Control system for pneumatic punch press feeders

Claim 2

A pneumatic feeder for intermittently advancing stock into the work station of a punch press or the like; comprising a frame; a feed slide reciprocally mounted on said frame; stock gripping means mounted said feed slide; fluid motor means for actuating said feed slide and stock gripping means through stock feed and index strokes; main valve means for controlling the operation of said fluid motor means; trigger means operative to control said valve means so as to cause initiation of a feed stroke of said feed slide; said trigger means including; a plunger means that is adapted to be movable between a normal position and a depressed position in response to the operation of said press; a pair of valves effectively coupled in series and each having a valving element associated therewith that is adapted to be displaced by the said movement of said plunger means so that both of said valves are open during only a predetermined portion of the movement of said plunger means; and reverse means operative in response to the terminal portion of said feed stroke for controlling said valve means so as to cause initiation of an index stroke of said feed slide.

Claim 3

Apparatus as defined by claim 1 wherein said plunger means is adapted to be moved downwardly from its said normal position in response to the downward movement of the ram of said press, and is adapted to be moved upwardly and back to its normal position in response to the upward movement of said ram.

Claim 4

Apparatus as defined by claim 1 or 2 wherein one of said pair of valves is a normally closed valve while the other of said pair of valves is a normally open valve.

Claim 5

Apparatus as defined by claim 1 or 2 wherein said predetermined portion of the movement of said plunger means comprises the terminal portion of the movement thereof back to its said normal position.

Claim 6

Apparatus as defined by claim 1 or 2 wherein said pair of valves comprises a first valve and a second valve that are effectively disposed in series, wherein during the movement of said plunger means away from said normal position either one or both of said valves are effectively closed so that there is then no pressure fluid output from said trigger means, and wherein during the movement of said plunger means back to its said normal position both of said valves are effectively open during only a limited period of time before one of said valves is again closed by the time said plunger means reaches its said normal position.

Claim 7

Apparatus as defined by claim 1 or 2 wherein each of said valves is a two-way valve.

Claim 8

Apparatus as defined by claim 1 or 2 wherein the valve that is effectively upstream from the other is a normally closed two-way valve.

Claim 9

Apparatus as defined by claim 1 or 2 wherein one of said pair of valves is a spool type two-way valve while the other of said pair of valves is a poppet type two-way valve.

Claim 10

Apparatus as defined by claim 1 or 2 wherein said trigger means includes a spring biased valve disc that is movably mounted on the lower portion of said plunger means.

Claim 11

Apparatus as defined by claim 1 or 2 wherein said main valve means includes two piloted three-way valves.

Claim 12

Apparatus as defined by claim 1 or 2 wherein said main valve means includes two individual piloted three-way valves, one of said three-way valves being adapted to control the operation of the other of said three-way valves.

Claim 13

A pneumatic feeder for intermittently advancing stock into the work station of a punch press or the like; comprising a frame; a feed slide reciprocally mounted on said frame; stock gripping means mounted said feed slide; fluid motor means for actuating said feed slide and stock gripping means through stock feed and index strokes; main valve means for controlling the operation of said fluid motor means; trigger means operative to control said valve means so as to cause initiation of a feed stroke of said feed slide; said trigger means comprising a plunger; valve body means carrying said plunger for axial reciprocation between normal and depressed positions; said body means including a fluid output line; shoulder means carried by said plunger, said shoulder means defining a movable portion of a normally open spool type two-way valve that is pneumatically coupled to said output line; a poppet valve disc axially movable carried adjacent the end of said plunger, said valve disc defining a movable portion of a normally closed two-way poppet valve that is pneumatically coupled through said normally open spool type two-way valve to said output line; said spool type two-way valve and said poppet type two-way valve both being open during the terminal portion of the axial movement of said plunger back to its said normal position; and reverse means operative in response to the terminal portion of said feed stroke for controlling said valve means so as to cause initiation of an index stroke of said feed slide.

Claim 14

A pneumatic feeder for intermittently advancing stock into the work station of a punch press or the like; comprising a frame; a feed slide reciprocally mounted on said frame; stock gripping means mounted said feed slide; fluid motor means for actuating said feed slide and stock gripping means through stock feed and index strokes; main valve means for controlling the operation of said fluid motor means; trigger means operative to control said valve means so as to cause initiation of a feed stroke of said feed slide; said trigger means comprising a plunger; valve body means carrying said plunger for axial reciprocation between normal and depressed positions; said body means including a fluid output line; shoulder means carried by said plunger, said shoulder means defining a movable portion of a normally open spool type two-way valve that is pneumatically coupled to said output line; a poppet valve disc axially movable carried adjacent the end of said plunger, said valve disc defining a movable portion of a normally closed two-way poppet valve that is pneumatically coupled through said normally open spool type two-way valve to said output line; said spool type two-way valve and said poppet type two-way valve both being open during the terminal portion of the axial movement of said plunger back to its said normal position; and reverse means operative in response to the terminal portion of said feed stroke for controlling said valve means so as to cause initiation of an index stroke of said feed slide.

Claim 15

Apparatus as defined by claim 12 wherein said plunger is adapted to be moved downwardly from its said normal position in response to the downward movement of the ram of said press, and is adapted to be moved upwardly and back to its normal position in response to the upward movement of said ram.

Claim 16

A pneumatic feeder for intermittently advancing stock into the work station of a punch press or the like; comprising a frame; a feed slide reciprocally mounted on said frame; stock gripping means mounted said feed slide; fluid motor means for actuating said feed slide and stock gripping means through stock feed and index strokes; main valve means for controlling the operation of said fluid motor means; trigger means operative to control said valve means so as to cause initiation of a feed stroke of said feed slide; reverse means operative in response to the terminal portion of said feed stroke for controlling said valve means so as to cause initiation of an index stroke of said feed slide; and safety means associated with said reverse means for permitting relatively small amounts of pressure fluid from the associated pneumatic circuit lines to exhaust to the surrounding atmospheric medium so that said valve means will not be actuated by small fluid pressure leaks that may be present in the associated pneumatic circuit.

Claim 17

A pneumatic feeder for intermittently advancing stock into the work station of a punch press or the like; comprising a frame; a feed slide reciprocally mounted on said frame; stock gripping means mounted said feed slide; fluid motor means for actuating said feed slide and stock gripping means through stock feed and index strokes; main valve means for controlling the operation of said fluid motor means; trigger means operative to control said valve means so as to cause initiation of a feed stroke of said feed slide; reverse means operative in response to the terminal portion of said feed stroke for controlling said valve means so as to cause initiation of an index stroke of said feed slide; and safety means associated with said reverse means for permitting relatively small amounts of pressure fluid from the associated pneumatic circuit lines to exhaust to the surrounding atmospheric medium so that said valve means will not be actuated by small fluid pressure leaks that may be present in the associated pneumatic circuit.

Claim 18

Apparatus as defined by claim 14 wherein said safety means includes a valve that is normally lightly biased to an open condition and is shiftable to a closed condition in response to a normal operative output pressure fluid flow from said trigger means.

Claim 19

Apparatus as defined by claim 15 wherein said valve comprises a part of said reverse means.

Claim 20

Apparatus as defined by claim 15 or 16 wherein said valve is adapted to be actuated to an open condition in response to the terminal portion of a feed stroke of said feed slide.

Claim 21

Apparatus as defined by claim 1 or 2 wherein safety means are provided for said trigger means for permitting relatively small amounts of pressure fluid from the associated pneumatic circuit lines to exhaust to the surrounding atmospheric medium so that said valve means will not be actuated by small fluid pressure leaks that may be present in the associated pneumatic circuit.

Claim 22

Apparatus as defined by claim 18 wherein said safety means includes a valve member that is normally lightly biased to open position and is shiftable to a closed position in response to a normal operative output pressure fluid flow from said trigger means.