GB695332A - Improvements in and relating to clutch control mechanisms - Google Patents

Abstract

695,332. Operating clutches. BOCHORY, M. July 10, 1951 [Sept. 6, 1950; Nov. 29, 1950; Feb. 27, 1951], No. 16378/51. Class 80 (ii). Automatic clutch-operating mechanism for a motor vehicle comprises an engine-suction servomotor 2 with suction and air valves 12, 27 which are normally closed by springs and opened by solenoids 11, 17 controlled by the accelerator 44 and gear lever 55, the servo-piston rod having grooves of different lengths controlling switches 9, 9<SP>1</SP>, 9<SP>2</SP> so that the final phase of the clutchengaging movement is retarded, and means being provided whereby, if the accelerator is depressed abruptly, this final phase of engagement is accelerated. As shown, these means comprise a switch 34 controlled by a spring-loaded diaphragm 30 subject to engine suction so as to be closed only on abrupt depression of the accelerator. The switches 9, 9<SP>1</SP>, 9<SP>2</SP> correspond to switches 50, 62 and 52 in the gear box which are closed when first or reverse, second, and third or fourth speeds are engaged. A switch 39 is closed when the accelerator is released, a switch 10 is opened when the suction valve 12 is opened, and a speed-responsive switch 53 opens above a predetermined speed. On release of the accelerator 44, so long as the predetermined speed is not exceeded, the solenoid 11 is always energised via switches 39, 53 and opens the suction valve 12 to cause clutch disengagement. Similarly, if the gear lever 55 is moved to neutral, solenoid 11 is always energised via switch 51 in the gear box, to cause clutch disengagement. When a gear, for instance first gear, is engaged and the accelerator is depressed (or held released if the predetermined speed is exceeded), the circuit through solenoid 11 is broken, valve 12 and switch 10 close, and solenoid 17 is energised via switches 10, 9, 50. Air valve 27 is thus opened and air has free access to the servo from a filter 28 through chamber D<SP>1</SP>, port 16b and chamber C'. The clutch moves rapidly towards engagement until switch 9 is closed by its groove. Valve 27 now closes and the final engagement is completed under the control of an adjustable bleed opening 16c. If, however, the accelerator is depressed abruptly, so as to reduce the suction effect, with third or fourth gear engaged, switch 34 closes and solenoid 17 is energised via switches 34, 52, thus by-passing the switch 9<SP>2</SP> and maintaining the air valve 27 open during the whole engaging movement. The switch 34 may, however, co-operate also with the other gear switches 50, 62. Instead of operating the switch 34, the diaphragm 30 may operate to open an additional air bleed valve, for speeding up the final engaging movement; or the switch or valve may be operated directly by the accelerator. Alternatively, in addition to the permanent adjustable air bleed opening 16c to the servo, there may be a permanent adjustable engine-suction bleed entry to the servo. Specification 683,049 is referred to.