GB831101A - Improvements relating to arrangements for controlling clutch engagement in motor vehicles - Google Patents

Abstract

831,101. Gearing for stopping and starting machinery. DAIMLER-BENZ A.G. Feb. 14, 1958 [Feb. 28, 1957], No. 4947/58. Class 80 (2). A motor-car having the conventional arrangement of an engine 2 driving through a clutch 4 and a change-speed gear 3 to a differential 18 and the car road wheels, has the clutch disengaged during selection and establishment of a new ratio by operation of a steering-columnmounted ratio-shift lever 13, which closes a switch to condition an electromagneticallyoperated pilot valve 15 so that it connects a source of low pressure, which may be a suction pump or, as shown, the inlet manifold 7 of the engine 2, to a pipe 10 leading to a clutch disengaging servomotor 6, establishment of the selected ratio and release of the shifter lever 13 opening the switch and breaking the circuit through the pilot valve control solenoid to disconnect the servomotor from the source of low pressure and instead allow atmospheric pressure to bleed slowly into the servomotor for gentle clutch re-engagement. If, while the clutch 4 is being re-engaged, the engine is required to drive the car, a torque-sensing switch 19 arranged on the casing 18 of the rear axle differential gear is closed to energize the controlling solenoid of a valve 24 which opens to admit air rapidly to the servomotor 6 for quick clutch re-engagement, the solenoid of the valve 24 being in series with a switch 25 closed only when the clutch is not fully engaged. The torque-sensing switch 19 may alternatively be mounted on the engine or gear-box of the motor-car.