Sparton Corporation

Greg R Pattock

The shift lever interlock system combines a shift lever position signal, interlock actuator extend and retract signals and vehicle system input signals (e.g., representing the service brake, ignition key-in, ignition circuit and vehicle battery voltage level) in a logic control circuit to lock the shift lever in the 'Park' position, except if the ignition key is not in the 'Lock' position and the service brake is depressed (applied) or the voltage of the battery is too low. The interlock system is not actuated to lock the shift lever in position when the shift lever is in positions other than as retained in the 'Park' position by the detent mechanism.

Shift lever interlock system

The ignition interlock system prevents movement of the ignition switch of a motor vehicle from the 'Off' position to the 'Lock' position unless the transmission selector is in the 'Park' position. The ignition interlock system includes a locking lever spring biased to lock the reciprocable slide of the ignition switch mechanism when the transmission selector is not in the 'Park' position. The locking lever is unlocked from the reciprocable slide by energization of a solenoid in response to the transmission selector being placed in the 'Park' position with the ignition key inserted in the ignition switch. A control circuit energizes or deenergizes the solenoid in response to input signals representing the transmission selector position and the ignition key in/out position.

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Spring Lake, MI, United States of America

Greg R Pattock