Safety interlock system

Claim 2

A safety interlock system to prevent theft or unauthorized removal of a vehicle having an engine system for powering said vehicle with an electrical component forming part of the engine system, said interlock system comprising: (a) a plurality of manually operable switch elements, each representing a separate indicium of a code for energizing said interlock system to enable operation of said vehicle when a plurality of said switch elements have been actuated in proper sequence to conform to the pre-established sequence of indicia of said code, (b) means operatively associated with said switch elements to generate an electrical signal in response to actuation of said switch elements, (c) a plurality of gating elements, each of said gating elements being connected in operative relation to certain of said switch elements and in such arrangement that said gating elements are switched to a proper state to generate an enabling signal in response to said electrical signals only when said switch elements are operated in proper sequence to conform to the pre-established sequence of indicia of said code and thereby permit operation of said electrical component, and (d) a plurality position selection switch operatively connected to said switch elements and having a first position where the interlock system is operatively connected to a source of electrical power to operate said electrical component, said selection switch having a second position where said interlock system is operatively connected to said gating elements to hold said gating elements in a proper state in accordance with the switch elements being operated in proper sequence for a predetermined time period.

Claim 3

The safety interlock system of claim 1 further characterized in that a solid state circuit component is associated with the electrical component and being connected to the output of said gating elements and being operable in response to said enabling signal to thereby permit operation of said electrical component.

Claim 4

The safety interlock system of claim 1 further characterized in that a pair of inverters is located at the output of said gating elements with one of said inverters being biased to one state and the other of said inverters being biased to an opposite state when said switch elements are operated in proper sequence to enable generation of said enabling signal.

Claim 5

The safety interlock system of claim 1 further characterized in that each of said plurality of switch elements produce an electrical signal of duration equal to the time that any particular one of said switch elements is actuated, and capacitor means is operatively connected to the output of said switch elements to compensate for the different durations of any of said electrical signals and transients therein.

Claim 6

The safety interlock system of claim 1 further characterized in that said gating elements are connected in a sequence so that a first of said gating elements is biased to a set state and a second of said gating elements is biased to a reset state; certain of the other gating elements in a first pre-established response being biased to a set state and the remaining gating elements in a second pre-established sequence being biased to a reset state.

Claim 7

The safety interlock system of claim 1 further characterized in that said source of electrical power is a direct current source.

Claim 8

A safety interlock system to prevent theft or unauthorized removal of a vehicle having an engine system for powering said vehible with electrical component forming part of the engine system, said interlock system comprising: (a) a plurality of manually operable switch elements, each representing a separate indicium of a code for energizing said interlock system to enable operation of said vehicle when a plurality of said switch elements have been actuated in proper sequence to conform to the pre-established sequence of indicia of said code, (b) means operatively associated with said switch elements to generate an electrical signal in response to actuation of said switch elements, (c) a plurality of electronic latches, each of said latches being connected in operative relation to certain of said switch elements and in such arrangement that said latches are switched to a proper state to generate an enabling signal in response to said electrical signals only when said switch elements are operated in proper sequence to conform to the pre-established sequence of indicia of said code, and (d) a plurality position selection switch operatively connected to said switch elements and having a first position where the interlock system is operatively connected to a direct current source of electrical power to operate said electrical component, said selection switch having a second position where said interlock system is operatively connected to said latches to hold said latches in proper state in accordance with the switch elements being operated in proper sequence for a predetermined time period.

Claim 9

A safety interlock system to prevent theft or unauthorized removal of a vehicle having an engine system for powering said vehible with electrical component forming part of the engine system, said interlock system comprising: (a) a plurality of manually operable switch elements, each representing a separate indicium of a code for energizing said interlock system to enable operation of said vehicle when a plurality of said switch elements have been actuated in proper sequence to conform to the pre-established sequence of indicia of said code, (b) means operatively associated with said switch elements to generate an electrical signal in response to actuation of said switch elements, (c) a plurality of electronic latches, each of said latches being connected in operative relation to certain of said switch elements and in such arrangement that said latches are switched to a proper state to generate an enabling signal in response to said electrical signals only when said switch elements are operated in proper sequence to conform to the pre-established sequence of indicia of said code, and (d) a plurality position selection switch operatively connected to said switch elements and having a first position where the interlock system is operatively connected to a direct current source of electrical power to operate said electrical component, said selection switch having a second position where said interlock system is operatively connected to said latches to hold said latches in proper state in accordance with the switch elements being operated in proper sequence for a predetermined time period.

Claim 10

The safety interlock system of claim 7 further characterized in that a solid state circuit component is associated with the elctrical components and is connected to the output of said latches, and being operable in response to said enabling signal to thereby permit operation of said electrical component.

Claim 11

The safety interlock system of claim 7 further characterized in that said solid state circuit component is a silicon-controlled rectifier.

Claim 12

The safety interlock system of claim 7 further characterized in that a pair of inverters is located at the output of said latches with one of said inverters being biased to one state and the other of said inverters being biased to an opposite state when said switch elements are operated in proper sequence to enable generation of said enabling signal.

Claim 13

The safety interlock system of claim 7 further characterized in that said electrical component is a starter solenoid of said vehicle.

Claim 14

The safety interlock system of claim 11 further characterized in that a second electrical component is operatively included in circuit controlling relation to said interlock system and is enabled simultaneously with enabling of said starter solenoid.

Claim 15

The safety interlock system of claim 7 further characterized in that each of said plurality of switch elements produce an electrical signal of duration equal to the time that any particular one of said switch elements if actuated, and capacitor means operating connected to the output of said switch elements to compensate for the different durations of any of said electrical signals and transients therein.

Claim 16

The safety interlock system of claim 7 further characterized in that said latches are comprised of a pair of cross-coupled gating elements.

Claim 17

The safety interlock system of claim 7 further characterized in that said gating elements are connected in a sequence so that a first of said gating elements is biased to a set state and a second of said gating elements is biased to a reset state, certain of the other gating elements in a first pre-established sequence being biased to a set state and the remaining gating elements in a second pre-established sequence being biased to a reset state.

Claim 18

The safety interlock system of claim 15 further characterized in that said gating elements are included in integrated circuit components.

Claim 19

The safety interlock system of claim 7 further characterized in that pairs of said latches comprise individual flip-flops.

Claim 20

The safety interlock system of claim 12 further characterized in that said second solid state circuit switching member is a silicon-controlled rectifier.

Claim 23

A safety interlock system to prevent theft or unauthorized removal of a vehicle having an engine system for powering said vehicle with first and second electrical components forming part of and necessary for starting or operation of the engine system, said interlock system comprising: (a) a plurality of manually operable switch elements, each representing a separate indicium of a code for energizing said interlock system to enable operation of said vehicle when a plurality of said switch elements have been actuated in proper sequence to conform to the pre-established sequence of indicia of said code, (b) means operatively associated with said switch elements to generate an electrical signal in response to actuation of said switch elements, said switch elements and said last named means to generate an electrical signal being located in proximity to the operator position of said vehicle, (c) a plurality of electronic latches, each of said latches being connected in operative relation to certain of said switch elements and in such arrangement that said latches are switched to a proper state to generate an enabling signal in response to said electrical signals only when said switch elements are operated in proper sequence to conform to the pre-established sequence of indicia of said code, (d) a first solid state circuit member directly connected to the first electrical component and being connected to the output of said latches, and being operable in response to said enabling signal to actuate said first solid state circuit member and thereby permit operation of said first electrical component, (e) a second solid state circuit switching member directly connected to the second switching member directly connected to the second electrical component and being connected to the output of said latches and being operable in response to said enabling signal to actuate said second solid state circuit member essentially simultaneously with the first circuit member and thereby permit operation of said second electrical component, said latches and solid state circuit member being located in said vehicle remote to the operator's position and in a relatively inaccessable location in said vehicle, and (f) actuating a plurality position selection switch operatively connected to said switch means and having a first position, said interlock system being operatively connected to a direct current source of electrical power to operate said electrical component upon shifting said selection switch to said first position, said selection switch having a second position where said interlock system is operatively connected to said latches to hold said latches in proper state in accordance with the switch elements being operated in proper sequence for a predetermined time period upon shifting said selection switch to said second position.

Claim 24

A safety interlock system to prevent theft or unauthorized removal of a vehicle having an engine system for powering said vehicle with first and second electrical components forming part of and necessary for starting or operation of the engine system, said interlock system comprising: (a) a plurality of manually operable switch elements, each representing a separate indicium of a code for energizing said interlock system to enable operation of said vehicle when a plurality of said switch elements have been actuated in proper sequence to conform to the pre-established sequence of indicia of said code, (b) means operatively associated with said switch elements to generate an electrical signal in response to actuation of said switch elements, said switch elements and said last named means to generate an electrical signal being located in proximity to the operator position of said vehicle, (c) a plurality of electronic latches, each of said latches being connected in operative relation to certain of said switch elements and in such arrangement that said latches are switched to a proper state to generate an enabling signal in response to said electrical signals only when said switch elements are operated in proper sequence to conform to the pre-established sequence of indicia of said code, (d) a first solid state circuit member directly connected to the first electrical component and being connected to the output of said latches, and being operable in response to said enabling signal to actuate said first solid state circuit member and thereby permit operation of said first electrical component, (e) a second solid state circuit switching member directly connected to the second switching member directly connected to the second electrical component and being connected to the output of said latches and being operable in response to said enabling signal to actuate said second solid state circuit member essentially simultaneously with the first circuit member and thereby permit operation of said second electrical component, said latches and solid state circuit member being located in said vehicle remote to the operator's position and in a relatively inaccessable location in said vehicle, and (f) actuating a plurality position selection switch operatively connected to said switch means and having a first position, said interlock system being operatively connected to a direct current source of electrical power to operate said electrical component upon shifting said selection switch to said first position, said selection switch having a second position where said interlock system is operatively connected to said latches to hold said latches in proper state in accordance with the switch elements being operated in proper sequence for a predetermined time period upon shifting said selection switch to said second position.

Claim 25

The safety interlock system of claim 20 further characterized in that said first and second solid state circuit members are silicon-controlled rectifiers.

Claim 26

The safety interlock system of claim 21 further characterized in that said first electrical component is a starter solenoid of said vehicle.

Claim 27

The method of claim 20 further characterized in that said method comprises locating said switch elements in proximity to the operator position of the vehicle and the latches and switching members in a position remote to the operator position.