Locking device for the gearbox of the FSO Warszawa car.
The arms of the engagement levers have recessed cams to locate the lever in position. Spring-pressed balls enter the prisms. There is a locking pin between the balls, which prevents the simultaneous activation of two transmissions. The length of the locking pin and the shape of the cams are so selected, that any gear can only be engaged then, when the second lever is in the neutral position (relaxed).
Gearboxes (above 3) is also equipped with a device, which prevents reverse gear from being engaged when driving forward. One of the safeguards against accidental engagement of the rear gear. In this case, the gear can be engaged only after overcoming the resistance of the spring and after pressing the plug into its seat.
In modern cars, the movement of the gear lever is transferred to the crossheads by means of a system of levers and cables, or by means of a hydraulic system., or electric. The principle of operation of these systems is the same, except that the carrier of the switching force is a liquid (hydrol) or a magnetic field, not mechanical tie rods.