Shift locking device for vehicle manual transmission

Claim 1

In a motor vehicle with a manual transmission having a striking rod operated by a manual shift lever to move upon shifting into gears, the combination with the striking rod of notch means formed in said striking rod; a locking plunger engageable in said notch means to lock said striking rod against movement thereof and a electrical switching arrangement so constructed and arranged that it causes said locking plunger to disengage from said notch means when predetermined safety measures have been taken by a driver of the motor vehicle, in which said switching arrangement comprises: a first switch which is normally open and is closed when a vehicle seat is occupied; a second switch which is normally open and is closed when a safety seat belt associated with the vehicle seat is worn; a relay switch cooperating with said second switch, which is closed when said second switch is open and open when said second switch is closed; a first relay coil in series with said first switch and said relay switch and having first and second pairs of relay contacts which are normally open, respectively; said first pair of relay contacts being in series with said second switch; said second pair of relay contacts being in parallel with said relay switch and in series with said first relay coil; a second relay coil in series with said first pair of relay contacts of said first relay coil and said second switch and having a pair or relay contacts which is normally closed; and means including a solenoid in series with said pair of relay contacts of said second relay coil for biasing said locking plunger to disengage from said notch means when said solenoid is deenergized and for biasing said locking plunger to engage said notch means when said solenoid is energized.