Automatic override for engine safety shutdown systems

Claim 2

An electronic override device for engine safety shutdown systems, comprising: means for monitoring engine operation and providing an electrical input signal condition in response to the restarting of a shutdown vehicle engine; a timer means for receiving said input signal and providing an electrical control signal having a progressive time-dependent variation after receipt of said input signal; and an electrical driver and switching circuit means for initially providing a first electrical output switching function and for receiving said control signal and providing a second electrical output switching function following the occurrence of a predetermined level condition of said control signal; said driver and switching circuit means being connectable to an engine-control component to override control of the engine bY such shutdown system by coupling said first and second output switching functions to said component to thereby control the same.

Claim 3

The override device of claim 1, wherein said means for monitoring provides a first electrical input signal condition during attempted engine restart and a second such signal condition upon termination of such attempt, and wherein said timer means provides said control signal variation only after receiving said second signal condition.

Claim 4

The override device of claim 1, wherein said timer means comprises a reactive charging and discharging circuit.

Claim 5

The override device of claim 1, wherein said driver and switching means comprises at least a level-detecting stage and a switching stage coupled thereto and controlled thereby.

Claim 6

The override device of claim 4, wherein said driver and switching means comprises at least one amplification stage.

Claim 7

The override device of claim 4, wherein said timer means comprises a reactive charging and discharging circuit.

Claim 8

The override device of claim 2, wherein said first input signal condition comprises the presence of an electrical voltage and said second such condition comprises the absence of such voltage, and wherein said timer means comprises a reactive circuit which is charged by said voltage and which discharges upon the absence thereof.

Claim 9

The override device of claim 7, wherein said driver and switching means comprises a multistage solid-state circuit having at least a level-detecting stage and a switching stage coupled thereto and controlled thereby.

Claim 10

A safety shutdown system for motor vehicle engines and the like, comprising in combination: a control component connected to a part of the engine to shut down operation of the engine upon receiving a predetermined shutdown signal condition and to permit engine operation upon receiving a different signal condition; at least one sensor means connected to the engine and coupled to said control component, for detecting a predetermined abnormal condition of engine operation and initiating such shutdown signal condition; an override means coupled to said control component for providing said different signal condition thereto for a predetermined time interval to permit engine operation during such interval despite such abnormal condition of operation; said override means including means for monitoring engine operation and providing an electrical input signal condition in response to the restarting of a shutdown engine, a timer means for receiving said input signal and providing an electrical control signal having a progressive time-dependent variation after receipt of said input signal, and an electrical driver and switching circuit means for receiving said control signal and providing an electrical output switching function prior to the occurrence of a predetermined level condition of said control signal, said driver and switching circuit means being connected to said control component to effect override thereof by coupling said output switching function thereto, such switching condition comprising said different signal condition.

Claim 11

A safety shutdown system for motor vehicle engines and the like, comprising in combination: a control component connected to a part of the engine to shut down operation of the engine upon receiving a predetermined shutdown signal condition and to permit engine operation upon receiving a different signal condition; at least one sensor means connected to the engine and coupled to said control component, for detecting a predetermined abnormal condition of engine operation and initiating such shutdown signal condition; an override means coupled to said control component for providing said different signal condition thereto for a predetermined time interval to permit engine operation during such interval despite such abnormal condition of operation; said override means including means for monitoring engine operation and providing an electrical input signal condition in response to the restarting of a shutdown engine, a timer means for receiving said input signal and providing an electrical control signal having a progressive time-dependent variation after receipt of said input signal, and an electrical driver and switching circuit means for receiving said control signal and providing an electrical output switching function prior to the occurrence of a predetermined level condition of said control signal, said driver and switching circuit means being connected to said control component to effect override thereof by coupling said output switching function thereto, such switching condition comprising said different signal condition.