Safety control circuit for presses and the like

Claim 2

In a multioperator controlled machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, at least two operator control stations each having self-returning manually operable control means thereat movable from a normal stable inoperative position to an unstable run position when it is desired to operate the drive means, each of said manually operable control means controlling normally open switch means and normally closed switch means which are respectively opened and closed when the manually operable control means is in its normal position and are respectively closed and opened when said control means is in its run position, electrically operated drive control means which when connected across a pair of powerlines operates said drive means, the improvement in a control circuit for controlling the connection of said drive control means across said powerlines, the control circuit comprising: manualcontrolled relay means connected across said powerlines separately through each of said normally closed switch means of said manually operable control means, the manual-controlled relay means remaining energized as long as any of said normally closed switch means of said manually operable control means remains closed, means connecting said normally open switch means of the manually operable control means of said operator control stations and said drive control means across said powerlines so the drive control means is energized only when all of the latter switch means are closed unless flow of current therethrough is otherwise prevented, and switch means controlled by said manual-controlled relay means for preventing the flow of said current through said drive control means while the manual-controlled relay means is energized.

Claim 3

The control circuit of claim 1 wherein: each of said manually operable control means at each operator station includes second normally closed switch means which is closed when the associated manually operable control means is in its normal position and is opened when the same is in its run position, and there are provided machine driven switch means which is closed except when said work producing portion of the machine is nearing a return to said starting position, antirepeat relay means connected across said powerlines through said machine driven switch means and the second normally closed switch means of said manually operable control means connected in series, switch means controlled by said manual-controlled relay means permitting the connection of said antirepeat relay means across said powerlines through said second normally closed switch means of said manually operable control means when the manual-controlled relay means is energized and preventing such connection when the manual-controlled relay means is deenergized by the simultaneous opening of all of the first mentioned normally closed switch means of said manually operable control means, switch means controlled by said antirepeat relay means for preventing the flow of current to said drive control means when the antirepeat relay means is deenergized and permitting such flow when said antirepeat relay means is energized, and switch means controlled by said antirepeat relay means which establishes a holding circuit in series with said machine driven means and bypassing said second normally closed switch means of said manually operable control means and said switch means controlled by sAid manual-controlled relay means.

Claim 4

The control circuit of claim 2 wherein said normally open switch means and said second normally closed switch means of said manually operable control means are connected between the same powerline and the associated respective drive control means and antirepeat relay means, and said current flow preventing switch means controlled by said antirepeat relay means includes a normally open switch located on the side of said normally opened switch means of the manually operable control means remote from said drive control means.

Claim 5

The control circuit of claim 2 wherein the said switch means controlled by said manual-controlled relay means includes a normally open switch located on one side of said second normally closed switch means of said manually operable control means, and there is further provided a normally closed switch controlled by said manual-controlled relay means which switch is connected in series between the normally open switch means of said manually operable control means and said drive control means so a short circuit occurring between said second normally closed switch means and said normally open switch means of said manually operable control means will not cause energization of said drive control means.

Claim 6

The control circuit of claim 2 wherein the first mentioned normally closed switch means of said manually operable control means at the operator stations are connected between one of said powerlines and said manual-controlled relay means and the second normally closed switch means of the manually operable control means at the operator stations are connected between the other powerline and said antirepeat relay means.

Claim 7

The control circuit of claim 1 wherein said drive control means include at least two separate drive control devices connected in separate branch circuits across said powerlines, both of which drive control devices must be energized to operate said drive means, and each of which devices is connected across said powerlines through different normally open switch means controlled by said manually operable control means.

Claim 8

In a machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, at least one operator control station having manually operable control means thereat operable from a normal inoperative condition to a run condition when it is desired to operate the drive means, the manually operable control means of each operator control station controlling normally open switch means and first and second normally closed switch means which are respectively opened and closed when the manually operable control means is in its normal condition and are respectively closed and opened when said control means is in its run condition, electrically operated drive control means which when connected across a pair of powerlines operates said drive means, the improvement in a control circuit for controlling the connection of said drive control means across said powerlines, the control circuit comprising: manual-controlled relay means connected across said powerlines through the first normally closed switch means of said manually operable control means of each operation control station, the manual-controlled relay means remaining energized as long as the normally closed switch means of said manually operable control means remains closed, means connecting said normally open switch means of the manually operable control means of each operator control station and said drive control means across said powerlines so the drive control means is initially energized only when the latter switch means are closed unless flow of current therethrough is otherwise prevented, switch means controlled by said manual-controlled relay means for preventing the flow of said current through said drive control means while the manual-controlled relay means is energized, machine driven switch means which is closed except when said work producing portion of the machine is nearing a return to said starting position, antirepeat relay means connected across said powerlines through said machine driven switch means and the second normally closed switch means of said manually operable control means, switch means controlled by said manual-controlled relay means permitting the connection of said antirepeat relay means across said powerlines through said second normally closed switch means of said manually operable control means when the manual-controlled relay means is energized and preventing such connection when the manual controlled relay means is deenergized by the opening of the first mentioned normally closed switch means of said manually operable control means, switch means controlled by said antirepeat relay means for preventing the flow of current to said drive control means when the antirepeat relay means is deenergized and permitting such flow when said antirepeat relay means is energized, switch means controlled by said antirepeat relay means which establishes a holding circuit in series with said machine driven means and bypasses said second normally closed switch means of said manually operable control means and said switch means controlled by said manual-controlled relay means, and said normally open switch means and said second normally closed switch means of said manually operable control means of each operator control station being respectively connected between the same powerline and the associated drive control means and antirepeat relay means, and said current flow preventing switch means controlled by said antirepeat relay means includes a normally open switch located on the side of said normally open switch means of the manually operable control means remote from said drive control means.

Claim 9

In a machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, at least one operator control station having manually operable control means thereat operable from a normal inoperative condition to a run condition when it is desired to operate the drive means, the manually operable control means of each operator control station controlling normally open switch means and first and second normally closed switch means which are respectively opened and closed when the manually operable control means is in its normal condition and are respectively closed and opened when said control means is in its run condition, electrically operated drive control means which when connected across a pair of powerlines operates said drive means, the improvement in a control circuit for controlling the connection of said drive control means across said powerlines, the control circuit comprising: manual-controlled relay means connected across said powerlines through the first normally closed switch means of said manually operable control means of each operation control station, the manual-controlled relay means remaining energized as long as the normally closed switch means of said manually operable control means remains closed, means connecting said normally open switch means of the manually operable control means of each operator control station and said drive control means across said powerlines so the drive control means is initially energized only when the latter switch means are closed unless flow of current therethrough is otherwise prevented, switch means controlled by said manual-controlled relay means for preventing the flow of said current through said drive control means while the manual-controlled relay means is energized, machine driven switch means which is closed except when said work producing portion of the machine is nearing a return to said starting position, antirepeat relay means connected across said powerlines through said machine driven switch means and the second normally closed switch means of said manually operable control means, switch means controlled by said manual-controlled relay means permitting the connection of said antirepeat relay means across said powerlines through said second normally closed switch means of said manually operable control means when the manual-controlled relay means is energized and preventing such connection when the manual controlled relay means is deenergized by the opening of the first mentioned normally closed switch means of said manually operable control means, switch means controlled by said antirepeat relay means for preventing the flow of current to said drive control means when the antirepeat relay means is deenergized and permitting such flow when said antirepeat relay means is energized, switch means controlled by said antirepeat relay means which establishes a holding circuit in series with said machine driven means and bypasses said second normally closed switch means of said manually operable control means and said switch means controlled by said manual-controlled relay means, and said normally open switch means and said second normally closed switch means of said manually operable control means of each operator control station being respectively connected between the same powerline and the associated drive control means and antirepeat relay means, and said current flow preventing switch means controlled by said antirepeat relay means includes a normally open switch located on the side of said normally open switch means of the manually operable control means remote from said drive control means.

Claim 10

In a machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, at least one operator control station having manually operable control means thereat operable from a normal inoperative condition to a run condition when it is desired to operate the drive means, the manually operable control means of each operation control station controlling normally open switch means and first and second normally closed switch means which are respectively opened and closed when the manually operable control means is in its normal condition and are respectively closed and opened when said control means is in its run condition, electrically operated drive control means which when connected across a pair of powerlines operates said drive means, the improvement in a control circuit for controlling the connection of said drive control means across said powerlines, the control circuit comprising: manual-controlled relay means connected across said powerlines through the first normally closed switch means of said manually operable control means of each operator control station, the manual-controlled relay means remaining energized as long as the normally closed switch means of said manually operable control means remains closed, means connecting said normally open switch means of the manually operable control means of each operator control station and said drive control means across said powerlines so the drive control means is initially energized only when the latter switch means are closed unless flow of current therethrough is otherwise prevented, switch means controlled by said manual-controlled relay means for preventing the flow of said current through said drive control means while the manual-controlled relay means is energized, machine driven switch means which is closed except when said work producing portion of the machine is nearing a return to said starting position, antirepeat relay means connected across said powerlines through said machine driven switch means and the second normally closed switch means of said manually operable control means, switch means controlled by said manual-controlled relay means permitting the connection of said antirepeat relay means across said powerlines through said second normally closed switch means of said manually operable control means when the manual-controlled relay means is energized and preventing such connection when the manual-controlled relay means is deenergized by the opening of the first mentioned normally closed switch means of said manually operable control means, switch means controlled by said antirepeat relay means for preventing the flow of current to said drive control means when the antirepeat relay means is deenergized and permitting such flow when said antirepeat relay means is energized, switch means controlled by said antirepeat relay means which establishes a holding circuit in series with said machine driven means and bypassing said second normally closed switch means of said manually operable control means and said switch means controlled by said manual-controlled relay means, said manual-controlled relay means including normally open switch means located on one side of said second normally closed switch means of said manually operable control means and normally closed switch means connected in series between the normally open switch means of said manually operable control means and said drive control means so a short circuit occurring between said second normally closed switch means and said normally open switch means of said manually operable control means will not cause energization of said drive control means.

Claim 11

In a machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, at least one operator control station having manually operable control means thereat operable from a normal inoperative condition to a run condition when it is desired to operate the drive means, the manually operable control means of each operation control station controlling normally open switch means and first and second normally closed switch means which are respectively opened and closed when the manually operable control means is in its normal condition and are respectively closed and opened when said control means is in its run condition, electrically operated drive control means which when connected across a pair of powerlines operates said drive means, the improvement in a control circuit for controlling the connection of said drive control means across said powerlines, the control circuit comprising: manual-controlled relay means connected across said powerlines through the first normally closed switch means of said manually operable control means of each operator control station, the manual-controlled relay means remaining energized as long as the normally closed switch means of said manually operable control means remains closed, means connecting said normally open switch means of the manually operable control means of each operator control station and said drive control means across said powerlines so the drive control means is initially energized only when the latter switch means are closed unless flow of current therethrough is otherwise prevented, switch means controlled by said manual-controlled relay means for preventing the flow of said current through said drive control means while the manual-controlled relay means is energized, machine driven switch means which is closed except when said work producing portion of the machine is nearing a return to said starting position, antirepeat relay means connected across said powerlines through said machine driven switch means and the second normally closed switch means of said manually operable control means, switch means controlled by said manual-controlled relay means permitting the connection of said antirepeat relay means across said powerlines through said second normally closed switch means of said manually operable control means when the manual-controlled relay means is energized and preventing such connection when the manual-controlled relay means is deenergized by the opening of the first mentioned normally closed switch means of said manually operable control means, switch means controlled by said antirepeat relay means for preventing the flow of current to said drive control means when the antirepeat relay means is deenergized and permitting such flow when said antirepeat relay means is energized, switch means controlled by said antirepeat relay means which establishes a holding circuit in series with said machine driven means and bypassing said second normally closed switch means of said manually operable control means and said switch means controlled by said manual-controlled relay means, said manual-controlled relay means including normally open switch means located on one side of said second normally closed switch means of said manually operable control means and normally closed switch means connected in series between the normally open switch means of said manually operable control means and said drive control means so a short circuit occurring between said second normally closed switch means and said normally open switch means of said manually operable control means will not cause energization of said drive control means.

Claim 12

In a machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, at least one operator control station having a pair of manually engageable control members to be respectively operated by the two hands of an operator and each separately operable from a normal inoperative condition to a run condition when it is desired to operate the drive means, each of said manually engageable control members directly controlling normally open switch means and first and second normally closed switch means which are respectively opened and closed when the control member is in its normal condition and are respectively closed and opened when said control member is in its run condition, electrically operated drive control means which when connected across a pair of powerlines operates said drive means, the improvement in a control circuit for controlling the connection of said drive control means across said powerlines, the control circuit comprising: manual-controlled relay means connected across said powerlines through the first normally closed switch means of said manually engageable control members, the manual-controlled relay means remaining energized as long as the normally closed switch means of said manually engageable control members remains closed, means connecting said normally open switch means of each of the manually engageable control members of each operator control station and said drive control means in series across said powerlines so the drive control means is energized only when the latter switch means are closed unless flow of current therethrough is otherwise prevented, switch means controlled by said manual-controlled relay means for preventing the flow of said current through said drive control means while the manual-controlled relay means is energized, machine driven switch means which is closed except when said work producing portion of the machine is nearing a return to said starting position, antirepeat relay means connected across said powerlines through said machine driven switch means and the second normally closed switch means of said manually engageable contrOl members connected in series, switch means controlled by said manual-controlled relay means permitting the connection of said antirepeat relay means across said powerlines through said second normally closed switch means of said manually engageable control members when the manual-controlled relay means is energized and preventing such connection when the manual-controlled relay means is deenergized by the opening of all of the first mentioned normally closed switch means of said manually engageable control members, switch means controlled by said antirepeat relay means for preventing the flow of current to said drive control means when the antirepeat relay means is deenergized and permitting such flow when said antirepeat relay means is energized, switch means controlled by said antirepeat relay means which establishes a holding circuit in series with said machine driven means and bypassing said second normally closed switch means of said manually engageable control members and said switch means controlled by said manual-controlled relay means, the first mentioned normally closed switch means of said manually engageable control members of each operator control station being connected between one of said powerlines and said manual-controlled relay means, and the second normally closed switch means of the manually engageable control members of each operator control station being connected between the other powerline and said antirepeat relay means, and short circuit current responsive means for deenergizing said control circuit when short circuit current flows due to a short circuit between said first and second normally closed switches of said manually engageable control members.

Claim 13

In a machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, at least one operator control station having a pair of manually engageable control members to be respectively operated by the two hands of an operator and each separately operable from a normal inoperative condition to a run condition when it is desired to operate the drive means, each of said manually engageable control members directly controlling normally open switch means and first and second normally closed switch means which are respectively opened and closed when the control member is in its normal condition and are respectively closed and opened when said control member is in its run condition, electrically operated drive control means which when connected across a pair of powerlines operates said drive means, the improvement in a control circuit for controlling the connection of said drive control means across said powerlines, the control circuit comprising: manual-controlled relay means connected across said powerlines through the first normally closed switch means of said manually engageable control members, the manual-controlled relay means remaining energized as long as the normally closed switch means of said manually engageable control members remains closed, means connecting said normally open switch means of each of the manually engageable control members of each operator control station and said drive control means in series across said powerlines so the drive control means is energized only when the latter switch means are closed unless flow of current therethrough is otherwise prevented, switch means controlled by said manual-controlled relay means for preventing the flow of said current through said drive control means while the manual-controlled relay means is energized, machine driven switch means which is closed except when said work producing portion of the machine is nearing a return to said starting position, antirepeat relay means connected across said powerlines through said machine driven switch means and the second normally closed switch means of said manually engageable contrOl members connected in series, switch means controlled by said manual-controlled relay means permitting the connection of said antirepeat relay means across said powerlines through said second normally closed switch means of said manually engageable control members when the manual-controlled relay means is energized and preventing such connection when the manual-controlled relay means is deenergized by the opening of all of the first mentioned normally closed switch means of said manually engageable control members, switch means controlled by said antirepeat relay means for preventing the flow of current to said drive control means when the antirepeat relay means is deenergized and permitting such flow when said antirepeat relay means is energized, switch means controlled by said antirepeat relay means which establishes a holding circuit in series with said machine driven means and bypassing said second normally closed switch means of said manually engageable control members and said switch means controlled by said manual-controlled relay means, the first mentioned normally closed switch means of said manually engageable control members of each operator control station being connected between one of said powerlines and said manual-controlled relay means, and the second normally closed switch means of the manually engageable control members of each operator control station being connected between the other powerline and said antirepeat relay means, and short circuit current responsive means for deenergizing said control circuit when short circuit current flows due to a short circuit between said first and second normally closed switches of said manually engageable control members.

Claim 14

In a machine which has a work producing portion movably by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, a pair of manually engageable control members to be respectively operated by different hands of one operator or the hands of separate operators and each operable from a normal inoperative condition to a run condition when it is desired to operate the drive means, each manually engageable control member directly controlling normally open switch means and normally closed switch means which are respectively opened and closed when the manually engageable control member is in its normal condition and are respectively closed and opened when said control member is in its run condition, and a pair of electrical power input terminals, the improvement comprising a control system for said machine including at least two separate drive control devices connected in separate branches across said power input terminals both of which drive control devices must be energized to operate said drive means, said normally open switch means controlled by said pair of manually engageable control members being respectively in said branches to effect energization thereof when closed, manual-controlled relay means connected across said power input terminals through said normally closed switch means of said manually engageable control members, the manual-controlled relay means remaining energized as long as said normally closed switch means of said manually engageable control member remains closed, and switch means in said respective branches controlled by said manual-controlled relay means for preventing the flow of current through said drive control devices while the manual-controlled relay means is energized.

Claim 15

In a machine which has a work producing portion movably by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, a pair of manually engageable control members to be respectively operated by different hands of one operator or the hands of separate operators and each operable from a normal inoperative condition to a run condition when it is desired to operate the drive means, each manually engageable control member directly controlling normally open switch means and normally closed switch means which are respectively opened and closed when the manually engageable control member is in its normal condition and are respectively closed and opened when said control member is in its run condition, and a pair of electrical power input terminals, the improvement comprising a control system for said machine including at least two separate drive control devices connected in separate branches across said power input terminals both of which drive control devices must be energized to operate said drive means, said normally open switch means controlled by said pair of manually engageable control members being respectively in said branches to effect energization thereof when closed, manual-controlled relay means connected across said power input terminals through said normally closed switch means of said manually engageable control members, the manual-controlled relay means remaining energized as long as said normally closed switch means of said manually engageable control member remains closed, and switch means in said respective branches controlled by said manual-controlled relay means for preventing the flow of current through said drive control devices while the manual-controlled relay means is energized.

Claim 16

The system of claim 10 wherein said normally closed switch means of said manually engageable control members are connected in parallel between said manual-controlled relay means at said power input terminals, wherein the manual-control relay means remains energized as long as any of said normally closed switch means remains closed.

Claim 17

The control system of claim 10 wherein said pair of manually engageable control members are loCated at one operator control station, and each of said manually engageable control members has additional normally open switch means operating similarly to the just mentioned normally open switch means thereof and located in the other of said branches in series with the normally open switch means of the other of said manually engageable control members so each branch has similarly operating normally open switch means of both manually engageable control members connected in series circuit relation.

Claim 18

The control circuit of claim 12 wherein there are two operator control stations each of which has a pair of said manually engageable control members wherein each control member has said normally open switch means located in both of said branches and connected in series with the normally open switch means of all of the other manually engageable control members.

Claim 19

An electrical control system to be energized from a pair of electrical power input terminals and including a pair of manually engageable control members to be respectively operated by different hands of one operator or the hands of separate operators operable from a normal inoperative condition to an operative condition when it is desired to effect a given operation, each of said manually engageable control members directly controlling normally open switch means which open and close when the control member is in its normal condition and are respectively closed and opened when the control member is in its operative condition, the improvement comprising: at least two separate operation producing devices connected in separate branches across said power input terminals, both of which operation producing devices must be energized to effect the desired operation, said normally open switch means of said pair of manually engageable control members being respectively in said branches to energize the same in their closed condition, said operation producing devices in one of said branches being connected between one of said power input terminals and the normally open switch means controlled by one of said manually engageable control members and the other of said operation producing devices is connected between the other power input terminal and the normally open switch means controlled by the other manually engageable control member, and short circuit current responsive means responsive to the flow of short circuit current resulting from a short circuit between said branches for deenergizing the branches.

Claim 20

An electrical control system to be energized from a pair of electrical power input terminals and including a pair of manually engageable control members to be respectively operated by different hands of one operator or the hands of separate operators operable from a normal inoperative condition to an operative condition when it is desired to effect a given operation, each of said manually engageable control members directly controlling normally open switch means which open and close when the control member is in its normal condition and are respectively closed and opened when the control member is in its operative condition, the improvement comprising: at least two separate operation producing devices connected in separate branches across said power input terminals, both of which operation producing devices must be energized to effect the desired operation, said normally open switch means of said pair of manually engageable control members being respectively in said branches to energize the same in their closed condition, said operation producing devices in one of said branches being connected between one of said power input terminals and the normally open switch means controlled by one of said manually engageable control members and the other of said operation producing devices is connected between the other power input terminal and the normally open switch means controlled by the other manually engageable control member, and short circuit current responsive means responsive to the flow of short circuit current resulting from a short circuit between said branches for deenergizing the branches.

Claim 21

In a machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, a pair of manually engageable self-returning control members to be respectively operated by different hands of one operator or the hands of different operators and each movable from a normal inoperative position to a run position when it is desired to operate the drive means, each of said manually engageable control members controlling at least one switch means operated in a given run position as long as the operator applies operating force to the associated control member, and a pair of electrical power input terminals the improvement in a control system for operating said drive means, said control system comprising: at least two electrically operated drive control devices which, when both are simultaneously connected across said power input terminals, operate said drive means, separate branch circuits coupled across said power input terminals in parallel and each including a different one of said electrically operated drive control devices and a different one of said switch means controlled by said manually engageable control members, said switch means energizing the associated drive control device when the associated manually engageable control member is held in the run position thereof, and said branch circuits including drive control relays and said drive control devices are solenoids which control said drive means and each solenoid is connected in parallel with one of said drive control relays through normally open switch means of the other drive control relay so the deenergization of one of said drive control relays will result in the deenergization of both solenoids.

Claim 22

In a machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, a pair of manually engageable self-returning control members to be respectively operated by different hands of one operator or the hands of different operators and each movable from a normal inoperative position to a run position when it is desired to operate the drive means, each of said manually engageable control members controlling at least one switch means operated in a given run position as long as the operator applies operating force to the associated control member, and a pair of electrical power input terminals the improvement in a control system for operating said drive means, said control system comprising: at least two electrically operated drive control devices which, when both are simultaneously connected across said power input terminals, operate said drive means, separate branch circuits coupled across said power input terminals in parallel and each including a different one of said electrically operated drive control devices and a different one of said switch means controlled by said manually engageable control members, said switch means energizing the associated drive control device when the associated manually engageable control member is held in the run position thereof, and said branch circuits including drive control relays and said drive control devices are solenoids which control said drive means and each solenoid is connected in parallel with one of said drive control relays through normally open switch means of the other drive control relay so the deenergization of one of said drive control relays will result in the deenergization of both solenoids.

Claim 23

The control system of claim 15 wherein each of said drive control devices are drive control relays and there is provided a relay holding branch circuit associated with each of said drive control relays each of which holding branch circuits includes machine operated switch means for maintaining the energization of the associated drive control relay when said manually engageable control members are released as said work producing portion of the machine returns to said starting position from said work producing position.

Claim 24

The control system of claim 16 wherein said drive control relays are connected between the respective holding branch circuits and the same power input terminals, and there is provided fuse means in each relay holding branch circuit on the same side of the associated drive control relays as said machine driven switch means which fuse means blows upon current flow therethrough only exceeding a given level occurring upon a short circuit between said relay holding branch circuits at a point between said drive control relays and said machine driven switch means and the opening in one of the relay holding branch circuits of said machine driven switch means which opens once each cycle of operation of the machine while the corresponding switch means in the other relay holding branch circuit remains closed when it is supposed to open, so the fuse means in the latter relay holding branch circuit carries all the current which normally flows in both relay holding branch circuits.

Claim 25

The control system of claim 15 wherein said drive means is a pressure responsive drive means which is rendered operable when the pressure applied thereto exceed a given level and which cannot normally be rendered operable below such level, and there is provided a pair of pressure control valves respectively controlled by said drive control devices and connected in parallel between a pressure supply line and an input line to said pressure responsive drive means, each of said valves being opened to connect said supply line to said input line when the associated drive control device is energized and being closed when the associated drive control device is deenergized, the pressure on said input line being a maximum when both of said valves are opened and a minimum when both of said valves are closed and valve responsive means responsive to the continued opening of one of said valves and the continued closing of another of said valves for effecting the continued deenergization of both drive control devices at least by the time the work producing portion of the machine returns to said starting position and independently of the operation of said switch means of said manually engageable control members.

Claim 26

The control system of claim 18 wherein there is provided additional switch means controlled by each of said manually engageable control members and relay means controlled by said additional switch means, said drive means is a gas pressure responsive drive means, said pressure on said input line being intermediate said minimum and maximum value when one of said valves is open and one of said valves is closed, said additional switch means of each manually engageable control member includes a normally closed switch which is opened when the control member is held in its run position, said valve responsive means is a pressure responsive switch including a normally closed switch which opens when the pressure of said input line reaches or exceeds said intermediate value, and the normally closed switch of each manually engageable control member is connected in series circuit with said normally closed switch of said pressure switch and said rElay means across said powerlines, said relay means when energized preparing both of said drive control devices for energization by the first mentioned switch means controlled by said manually engageable control members when the latter are all operated at the beginning of a machine cycle.

Claim 27

The control system of claim 16 wherein said machine operated switch means in said holding branch circuit open when said work producing portion of the machine returns to said starting position and close when said work producing portion of the machine reaches said work producing position.

Claim 28

The control system of claim 19 wherein said drive means is pressure operated by separate valves controlled respectively by said drive control devices, each valve being normally open when the associated drive control device is energized and being closed when the associated drive control device is deenergized, said drive means being normally operable only when both of said valves are opened, and means responsive to the closure of both of said valves for opening both of said holding branch circuits.

Claim 29

The control system of claim 15 wherein there is provided means for deenergizing said drive control devices once each cycle of operation of the machine, said drive means is a pressure responsive drive means which is rendered operable when the pressure applied thereto exceeds a given level and which cannot normally be rendered operable below such level, and there is provided a pair of pressure control valves respectively controlled by said drive control devices and connected in parallel between a pressure supply line and an input line to said pressure responsive drive means, each of said valves being opened to connect said supply line to said input line when the associated drive control device is energized and being closed when the associated drive control device is deenergized, the pressure on said input line being a maximum when both of said valves are opened, a minimum when both of said valves are closed and means responsive to the continued opening of one of said valves and the continued closing of another of said valves and the deenergization of at least one of said drive control devices for effecting the continued deenergization of both control devices at least by the time the work producing portion of the machine returns to said starting position and independently of the operation of said switch means of said manually engageable control members.

Claim 30

The control system of claim 15 wherein said pair of manually engageable control members are located at one operator control station and each of said manually engageable control members has additional switch means operating similarly to the first mentioned switch means thereof and located in the other of said branches so each branch has similarly operating switch means of both manually engageable control members.

Claim 31

An electrical control system comprising a power input source comprising a transformer having a primary winding to be connected to a source of alternating current and a center-tapped secondary winding, the center tap of which is grounded and the opposite ends of which form voltage input terminals for a control circuit, a control circuit comprising a pair of powerlines coupled to said voltage input terminals, a pair of manually engageable control members, at least two circuit branches coupled directly across said powerlines and each including an operation producing device which effects a desired operation when energized and a different control switch means in series therewith operated directly by a different one of said pair of manually engageable control members for normally controlling the energization and deenergization of said operation producing devices, said control switch means in one of said circuit branches being coupled only between one of said powerlines and the associated operation producing device and the control switch means in the other circuit branch being coupled only between the other powerline and the associated operation producing device whereby any short circuit between said control switch means of said circuit branches or the grounding of any portion of either circuit branch will cause a short circuit current to flow in one or both portions of the secondary winding of said transformer, and short circuit current responsive means for sensing the flow of any of said short circuit currents for disconnecting power to said powerlines.

Claim 32

An electrical control system comprising a power input source comprising a transformer having a primary winding to be connected to a source of alternating current and a center-tapped secondary winding, the center tap of which is grounded and the opposite ends of which form voltage input terminals for a control circuit, a control circuit comprising a pair of powerlines coupled to said voltage input terminals, a pair of manually engageable control members, at least two circuit branches coupled directly across said powerlines and each including an operation producing device which effects a desired operation when energized and a different control switch means in series therewith operated directly by a different one of said pair of manually engageable control members for normally controlling the energization and deenergization of said operation producing devices, said control switch means in one of said circuit branches being coupled only between one of said powerlines and the associated operation producing device and the control switch means in the other circuit branch being coupled only between the other powerline and the associated operation producing device whereby any short circuit between said control switch means of said circuit branches or the grounding of any portion of either circuit branch will cause a short circuit current to flow in one or both portions of the secondary winding of said transformer, and short circuit current responsive means for sensing the flow of any of said short circuit currents for disconnecting power to said powerlines.

Claim 33

The electrical control system of claim 24 wherein each of said pair of manually engageable control members has additional control switch means operating similarly to the first mentioned switch means thereof and located in the other of said branches so each branch has similarly operating switch means of both pair of manually engageable control members, and each of said pair of manually engageable control members and the associated control switch means forming a switch unit wherein the control switch means can be short circuited if the switch unit is damaged.

Claim 34

The electrical control system of claim 25 wherein said operation producing devices in said circuit branches cooperate to produce the same given operation if both are energized and fail to perform said operation if only one or neither of same are energized.

Claim 35

A machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, said drive means being a gas pressure responsive drive means which is rendered operable when the pressure applied thereto exceeds a given level and which cannot normally be rendered operable below such level, a pair of pressure control valves, drive control devices controlling said valves, said control valves being connected in parallel between a pressure supply line and an input line to said pressure responsive drive means, each of said valves being opened to connect said supply line to said input line when the associated drive control device is in a valve opening condition and being closed when the associated drive control device is in a valve closing condition, the pressure on said input line being a maximum when both of said valves are opened, a minimum when both of said valves are closed and an intermediate valve when one of said valves is opened and one of the valves is closed, a control system for operating said valve operating drive control devices, said control system including means responsive to the opening of one of said valves and the closing of the other of same for operating both of said drive control devices to a valve closing condition if not already in such a condition and pressure responsive means responsive to the presence of said intermediate pressure in said input line at a time in the machine cycle when the pressure thereat should be zero for operating both of said drive control devices to their valve closing conditions.

Claim 36

A machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, said drive means being a gas pressure responsive drive means which is rendered operable when the pressure applied thereto exceeds a given level and which cannot normally be rendered operable below such level, a pair of pressure control valves, drive control devices controlling said valves, said control valves being connected in parallel between a pressure supply line and an input line to said pressure responsive drive means, each of said valves being opened to connect said supply line to said input line when the associated drive control device is in a valve opening condition and being closed when the associated drive control device is in a valve closing condition, the pressure on said input line being a maximum when both of said valves are opened, a minimum when both of said valves are closed and an intermediate valve when one of said valves is opened and one of the valves is closed, a control system for operating said valve operating drive control devices, said control system including means responsive to the opening of one of said valves and the closing of the other of same for operating both of said drive control devices to a valve closing condition if not already in such a condition and pressure responsive means responsive to the presence of said intermediate pressure in said input line at a time in the machine cycle when the pressure thereat should be zero for operating both of said drive control devices to their valve closing conditions.

Claim 37

In combination, an operator controlled machine which has a work producing portion movable by the operation of pressure responsive drive means from a remote starting position, where an operator is relatively safe, to a work producing position, where it can injure an operator in the vicinity thereof, and then back to said starting position; operator control station means with manually operable control means, said drive means being rendered operable when the pressure applied thereto exceeds a given level and is normally inoperable at input pressures below such level; a pair of pressure control valves having movable valve opening and closing parts and being connected in parallel between a pressure supply line and an input line to said pressure responsive drive means, the pressure on said input line being a maximum when both of said valves are opened to operate said pressure responsive drive means and less than said maximum value where said pressure responsive drive means is inoperative when both or One of the valves is closed; drive control devices for controlling said valves; and a drive control system for operating said drive control devices, said control system including first means responsive to operation of said manually operable control means for operating said drive control devices from a normal valve closing condition to a valve opening condition, second means responsive to the movement of said work producing portion of said machine between said work producing position to said starting position for continuing the operation of said drive control devices in said valve opening condition independently of the operation of said manually operable control means until said work producing portion of the machine at least returns to said starting position; third means responsive to either one of said valves being in an open position for preventing the operation of said drive control devices by said manually operable control means, and fourth means responsive to either one of both of said valves being in a closed position for terminating the operation of said drive control devices upon release of said manually operable control means.

Claim 38

In combination, an operator controlled machine which has a work producing portion movable by the operation of pressure responsive drive means from a remote starting position, where an operator is relatively safe, to a work producing position, where it can injure an operator in the vicinity thereof, and then back to said starting position; operator control station means with manually operable control means, said drive means being rendered operable when the pressure applied thereto exceeds a given level and is normally inoperable at input pressures below such level; a pair of pressure control valves having movable valve opening and closing parts and being connected in parallel between a pressure supply line and an input line to said pressure responsive drive means, the pressure on said input line being a maximum when both of said valves are opened to operate said pressure responsive drive means and less than said maximum value where said pressure responsive drive means is inoperative when both or One of the valves is closed; drive control devices for controlling said valves; and a drive control system for operating said drive control devices, said control system including first means responsive to operation of said manually operable control means for operating said drive control devices from a normal valve closing condition to a valve opening condition, second means responsive to the movement of said work producing portion of said machine between said work producing position to said starting position for continuing the operation of said drive control devices in said valve opening condition independently of the operation of said manually operable control means until said work producing portion of the machine at least returns to said starting position; third means responsive to either one of said valves being in an open position for preventing the operation of said drive control devices by said manually operable control means, and fourth means responsive to either one of both of said valves being in a closed position for terminating the operation of said drive control devices upon release of said manually operable control means.

Claim 39

The combination of claim 28 wherein said third and fourth means includes means controlled directly by the movement of said movable valve parts.

Claim 40

The combination of claim 28 wherein said third and fourth means includes means controlled directly by the pressure in said input line.

Claim 41

The combination of claim 28 wherein said drive control devices are solenoids which open said valves when energized; said control system includes antirepeat relay means which when energized locks into such energized state and prepares said drive control devices for energization by said manually operable control means, first machine drive means which breaks the locked-in condition of said antirepeat relay means as said work producing portion of said machine is returned to said starting position, means including machine driven means which lockin said solenoids into their energized condition when said work producing portion of the machine moves between said work producing position and said starting position, and said third and fourth means includes normally closed switches in series with said antirepeat relay means to prevent initial energization of same when open and normally open switches in holding circuit branches of said solenoids to break the holding circuit branches when open.

Claim 42

A machine which has a work producing portion movable by an operating drive means from a remote starting position, when an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, operator control station means each having self-returning manually operable control means thereat movable from a normal inoperative position to a single cycle run position when it is desired to operate the drive means, said manually operable control means controlling normally open switch means and normally closed switch means which are respectively opened and closed when the manually operable control means is in its normal position and are respectively closed and opened when said control means is in its run position, first machine driven switch means which is closed except when said work producing portion of the machine is nearing a return to said starting position and antirepeat relay means connected across said powerlines through said machine driven switch means and the normally closed switch means of said manually operable control means connected in series, two separate electrically operable drive control relays connected in separate branch circuits across said powerlines, both of which drive control relays must be energized to operate said drive means and each of which relays is connected across said powerlines through a different normally open switch means controlled by said manually operable control means, holding branch circuits between said drive control relays and one of said powerlines and incLuding switch means controlled by said drive control relays to hold the same in an energized state independently of the opened or closed condition of said normally open switch means of said manually operable control means, second machine driven switch means which interrupts said holding circuits of said drive control relays when said work producing portion of the machine returns to said starting position, switch means controlled by said antirepeat relay means for preventing a renewed energization of the drive control relays if the antirepeat relay remains deenergized after said holding circuits are opened by said second machine driven switch means and permitting such energization when said antirepeat relay means is energized, and antirepeat relay circuit check means comprising first and second normally closed switch means controlled by said antirepeat relay means so as to be closed and opened respectively during the deenergization and energization thereof and connected in series respectively with said separate drive control devices, and third and fourth separately machine driven normally closed switch means connected across said first and second normally closed switch means of said antirepeat relay means, said third and fourth separately machine driven normally closed switch means being opened momentarily during the return of said work producing portion of the machine driven switch means is opened to break the holding circuits of the associated drive control relays and terminate operation of said drive means if the antirepeat relay means did not become deenergized by proper operation of said first machine driven switch means.

Claim 43

A machine which has a work producing portion movable by an operating drive means from a remote starting position, when an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, operator control station means each having self-returning manually operable control means thereat movable from a normal inoperative position to a single cycle run position when it is desired to operate the drive means, said manually operable control means controlling normally open switch means and normally closed switch means which are respectively opened and closed when the manually operable control means is in its normal position and are respectively closed and opened when said control means is in its run position, first machine driven switch means which is closed except when said work producing portion of the machine is nearing a return to said starting position and antirepeat relay means connected across said powerlines through said machine driven switch means and the normally closed switch means of said manually operable control means connected in series, two separate electrically operable drive control relays connected in separate branch circuits across said powerlines, both of which drive control relays must be energized to operate said drive means and each of which relays is connected across said powerlines through a different normally open switch means controlled by said manually operable control means, holding branch circuits between said drive control relays and one of said powerlines and incLuding switch means controlled by said drive control relays to hold the same in an energized state independently of the opened or closed condition of said normally open switch means of said manually operable control means, second machine driven switch means which interrupts said holding circuits of said drive control relays when said work producing portion of the machine returns to said starting position, switch means controlled by said antirepeat relay means for preventing a renewed energization of the drive control relays if the antirepeat relay remains deenergized after said holding circuits are opened by said second machine driven switch means and permitting such energization when said antirepeat relay means is energized, and antirepeat relay circuit check means comprising first and second normally closed switch means controlled by said antirepeat relay means so as to be closed and opened respectively during the deenergization and energization thereof and connected in series respectively with said separate drive control devices, and third and fourth separately machine driven normally closed switch means connected across said first and second normally closed switch means of said antirepeat relay means, said third and fourth separately machine driven normally closed switch means being opened momentarily during the return of said work producing portion of the machine driven switch means is opened to break the holding circuits of the associated drive control relays and terminate operation of said drive means if the antirepeat relay means did not become deenergized by proper operation of said first machine driven switch means.

Claim 44

In combination, a machine having a work producing portion movable by an operating drive means from a starting remote position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position; manually operable self-returning control means movable from an inoperative position to a run position when it is desired to operate said drive means; manually operable function control means having stable off, single cycle operation and continuous operation positions; key operable control means having stable continuous-off and continuous-on positions; means responsive to the simultaneous positioning of said manually operable function control means to its single cycle operation position and said manually operable self-returning control means to its run position for operating said drive means for a single cycle which moves said work producing portion of the machine from said starting position to said work producing position and back to said starting position; and means responsive to the simultaneous positioning of said key-operated control means to its continuous on position, said manually operable function control means to said continuous operation position and said manually operable self-returning control means to the run position for continuously operating said drive means, continuously to move said work producing portion of the machine repeatedly between said starting and work producing positions.

Claim 45

In combination, a machine having a work producing portion movable by an operating drive means from a starting remote position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position; manually operable self-returning control means movable from an inoperative position to a run position when it is desired to operate said drive means; manually operable function control means having stable off, single cycle operation and continuous operation positions; key operable control means having stable continuous-off and continuous-on positions; means responsive to the simultaneous positioning of said manually operable function control means to its single cycle operation position and said manually operable self-returning control means to its run position for operating said drive means for a single cycle which moves said work producing portion of the machine from said starting position to said work producing position and back to said starting position; and means responsive to the simultaneous positioning of said key-operated control means to its continuous on position, said manually operable function control means to said continuous operation position and said manually operable self-returning control means to the run position for continuously operating said drive means, continuously to move said work producing portion of the machine repeatedly between said starting and work producing positions.

Claim 46

The combination of claim 33 wherein said manually operable self-returning control means includes a first self-returning control which must be continuously operated in its run position to effect a continuous cycle of operation for a period wherein said work producing portion of the machine moves from its starting to its work producing position.

Claim 47

The combination of claim 34 wherein said manually operable self-returning control means further includes a second self-returning manually operable control which must be momentarily operated prior to said first self-returning control means to effect the initiation of the continuous cycle of operation by operation of said key operable control means to its continuous on position and the operation of said first self-returning manually operable control continuously during the interval when said work producing portion Of the machine is moving between said starting and work producing positions.

Claim 48

In combination, a machine having a work producing portion movable by an operating drive means from a starting remote position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position; manually operable self-returning control means movable from an inoperative position to a run position when it is desired to operate said drive means; manually operable function control means having a movable handle which is movable generally in a given plane to first and second positions in said plane respectively, to move said control means into positions for obtaining a stable off and single cycle operation positions, and said manually movable handle being movable into a third position in said plane where the handle is then movable in a direction transverse to said plane into a second plane where said control means is in a continuous operating position; key operable control means having stable continuous-off and continuous-on positions; means responsive to the simultaneous positioning of said manually operable function control means to its single cycle operation position and said manually operable self-returning control means to the run position for operating said drive means for a single cycle which moves said work producing portion of the machine from said starting position to said work producing position and back to said starting position; and means responsive to the simultaneous positioning of said key-operated control means to its continuous on position, said manually operable function control means to said continuous operation position and said manually operable self-returning control means to the run position for continuously operating said drive means continuously to move said work producing portion of the machine between said starting and work producing positions.

Claim 49

In combination, a machine having a work producing portion movable by an operating drive means from a starting remote position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position; manually operable self-returning control means movable from an inoperative position to a run position when it is desired to operate said drive means; manually operable function control means having a movable handle which is movable generally in a given plane to first and second positions in said plane respectively, to move said control means into positions for obtaining a stable off and single cycle operation positions, and said manually movable handle being movable into a third position in said plane where the handle is then movable in a direction transverse to said plane into a second plane where said control means is in a continuous operating position; key operable control means having stable continuous-off and continuous-on positions; means responsive to the simultaneous positioning of said manually operable function control means to its single cycle operation position and said manually operable self-returning control means to the run position for operating said drive means for a single cycle which moves said work producing portion of the machine from said starting position to said work producing position and back to said starting position; and means responsive to the simultaneous positioning of said key-operated control means to its continuous on position, said manually operable function control means to said continuous operation position and said manually operable self-returning control means to the run position for continuously operating said drive means continuously to move said work producing portion of the machine between said starting and work producing positions.

Claim 50

In combination, a machine having a work producing portion movable by an operating drive means from a starting remote position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position; at least one manually operable self-returning control means movable from a stable inoperative position to an unstable operative position when it is desired to operate said drive means; and manually operable function control means having a handle coupled thereto for moving the same between discrete stable off, single cycle, inch and continuous operating positions, said inch operating position being located between said single cycle and continuous operation positions so the function control means cannot readily be moved inadvertently from the single cycle operation position to said continuous operation position; means responsive to the simultaneous position of said manually operable function control means to its single cycle operation position and all manually operable self-returning control means to the operative position thereof for operating said drive means for a single cycle which moves said work producing portion of the machine from said starting position to said work producing position while said self-returning control means is held in said operative position and then back to said starting position even when said self-returning control means is released; means responsive to the simultaneous positioning of said manually operable function control means to said continuous operation position and all manually operable self-returning control means to the operative position thereof for obtaining the operation of said drive means continuously to move said work producing portion of the machine repeatedly between said starting and work producing positions; and means responsive to the simultaneous positioning of said manually operable function control means to said inch operation position and said manually operable self-returning control means to the operative position thereof for obtaining the operation of said drive means only as long as the latter self-returning control means is held in said operative position.

Claim 51

In combination, a machine having a work producing portion movable by an operating drive means from a starting remote position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position; at least one manually operable self-returning control means movable from a stable inoperative position to an unstable operative position when it is desired to operate said drive means; and manually operable function control means having a handle coupled thereto for moving the same between discrete stable off, single cycle, inch and continuous operating positions, said inch operating position being located between said single cycle and continuous operation positions so the function control means cannot readily be moved inadvertently from the single cycle operation position to said continuous operation position; means responsive to the simultaneous position of said manually operable function control means to its single cycle operation position and all manually operable self-returning control means to the operative position thereof for operating said drive means for a single cycle which moves said work producing portion of the machine from said starting position to said work producing position while said self-returning control means is held in said operative position and then back to said starting position even when said self-returning control means is released; means responsive to the simultaneous positioning of said manually operable function control means to said continuous operation position and all manually operable self-returning control means to the operative position thereof for obtaining the operation of said drive means continuously to move said work producing portion of the machine repeatedly between said starting and work producing positions; and means responsive to the simultaneous positioning of said manually operable function control means to said inch operation position and said manually operable self-returning control means to the operative position thereof for obtaining the operation of said drive means only as long as the latter self-returning control means is held in said operative position.

Claim 52

The combination of claim 37 wherein said continuous operation position of said manually operable function control means is the position furthest removed from the off position thereof.

Claim 53

The combination of claim 37 wherein said manually operable function control means has a neutral or inoperative stable position between the single cycle and inch positions, and between said inch and continuous operation positions, at which neutral or inoperative positions said drive means is inoperative.

Claim 54

The combination of claim 37 wherein there is provided key operable control means having stable off and on positions, said means which is responsive to the simultaneous positioning of said manually operable function control means and the continuous operation position of said manually operable self-returning control means also requiring the simultaneous positioning of said key operable control means in the stable on position thereof to effect the continuous operation of said drive means.

Claim 55

A machine having a work producing portion movable by an operating drive means from a starting remote position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof, at least one depressible self-returning control means movable by application of manual force from a stable inoperative extended position to an unstable depressed operative position when it is desired to operate said drive means, a second initially nondepressible self-returning control means movable by manual force from a stable inoperative position to an unstable operative position when it is desired to operate said drive means, and control means responsive to said depressible and nondepressible self-returning control means for inhibiting the operation of said drive means when either of said manually operable self-returning control means are in their stable inoperative positions and for operating said drive means when said depressible and nondepressible self-returning control means are simultaneously manually held in their unstable operative positions.

Claim 56

A machine having a work producing portion movable by an operating drive means from a starting remote position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof, at least one depressible self-returning control means movable by application of manual force from a stable inoperative extended position to an unstable depressed operative position when it is desired to operate said drive means, a second initially nondepressible self-returning control means movable by manual force from a stable inoperative position to an unstable operative position when it is desired to operate said drive means, and control means responsive to said depressible and nondepressible self-returning control means for inhibiting the operation of said drive means when either of said manually operable self-returning control means are in their stable inoperative positions and for operating said drive means when said depressible and nondepressible self-returning control means are simultaneously manually held in their unstable operative positions.

Claim 57

In combination, a multioperator controlled machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position; at least two operator control stations, each operator control station having self-returning manually operable control means thereat movable from a normal inoperative position to a run position when it is desired to operate the drive means, each of said manually operable control means controlling switch means, each manually operable control means and the associated switch means being part of an operator unit having contact terminals removably engageable with complementary contact terminals at the associated operator control station; electrically operated drive control means which when connected across a pair of powerlines operates said drive means; a control circuit for controlling the connection of said drive control means across said powerlines, the control circuit comprising circuit-forming means interconnecting said powerlines, drive control means, switch means and at least some of said complementary contact terminals for normally energizing said drive control means when said manually operable control means of all the operator control means of all the operator control stations are simultaneously operated to their run positions; each of said operator units having a jumper connected by some of said complementary contact terminals at a point of said control circuit in series with said powerlines so the absence of jumpers will render the control circuit inoperative; and dummy units each of which can be substituted for one of said operator units and has contact terminals removably engageable with at least some of the complementary contact terminals of the operator control stations of the operator unit it is to replace, each of said dummy units having jumpers which interconnect some of said complementary contact terminals but not said complementary contact terminals which connect said operator unit jumpers.

Claim 58

In combination, a multioperator controlled machine which has a work producing portion movable by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position; at least two operator control stations, each operator control station having self-returning manually operable control means thereat movable from a normal inoperative position to a run position when it is desired to operate the drive means, each of said manually operable control means controlling switch means, each manually operable control means and the associated switch means being part of an operator unit having contact terminals removably engageable with complementary contact terminals at the associated operator control station; electrically operated drive control means which when connected across a pair of powerlines operates said drive means; a control circuit for controlling the connection of said drive control means across said powerlines, the control circuit comprising circuit-forming means interconnecting said powerlines, drive control means, switch means and at least some of said complementary contact terminals for normally energizing said drive control means when said manually operable control means of all the operator control means of all the operator control stations are simultaneously operated to their run positions; each of said operator units having a jumper connected by some of said complementary contact terminals at a point of said control circuit in series with said powerlines so the absence of jumpers will render the control circuit inoperative; and dummy units each of which can be substituted for one of said operator units and has contact terminals removably engageable with at least some of the complementary contact terminals of the operator control stations of the operator unit it is to replace, each of said dummy units having jumpers which interconnect some of said complementary contact terminals but not said complementary contact terminals which connect said operator unit jumpers.

Claim 59

The combination of claim 42 where each of said dummy units leave additional portions of said control circuit unjumpered so an undesired short circuit across one of the unjumpered portions of the circuit when all of the operator units are replaced by dummy unit will still leave the control circuit inoperative.

Claim 60

In combination, a multioperator controlled machine which has a work producing portion movably by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, at least two operator control stations, each operator control station having self-returning manually operable control means thereat movable from a normal inoperative position to a runs position when it is desired to operate the drive means, said operable control means at each operator control station being part of an electrical operator unit having contact terminals removably engageable with complementary contact terminals at the associated operator control station; each of said operator units having a machine stopping control thereon for rendering said drive means inoperable to stop the machine at any point in an operating cycle, and each of said operator units further having an indicating light which becomes automatically energized to indicate that the unit is operable when the unit contact terminals engage with said complementary contact terminals at the operator control station involved.

Claim 61

In combination, a multioperator controlled machine which has a work producing portion movably by an operating drive means from a remote starting position, where an operator is relatively safe, to a work producing position where it can injure an operator in the vicinity thereof and then back to said starting position, at least two operator control stations, each operator control station having self-returning manually operable control means thereat movable from a normal inoperative position to a runs position when it is desired to operate the drive means, said operable control means at each operator control station being part of an electrical operator unit having contact terminals removably engageable with complementary contact terminals at the associated operator control station; each of said operator units having a machine stopping control thereon for rendering said drive means inoperable to stop the machine at any point in an operating cycle, and each of said operator units further having an indicating light which becomes automatically energized to indicate that the unit is operable when the unit contact terminals engage with said complementary contact terminals at the operator control station involved.