Patent GB-406683-A (GB)
Title: Controlling and driving mechanism for motor vehicles
IPC: B60K23/02
Filed: 1932-07-23
Abstract: 406,683. Operating clutches. BENDIX AVIATION CORPORATION, 105, West Adams Street, Chicago, U.S.A. July 23, 1932. No. 20805. Convention date, July 23, 1931. [Class 80 (ii).] Clutch control mechanism for vehicles having a power-operated clutch wherein a speed-controlled governor permits the clutch to be engaged when the speed of a driving element is substantially equal to the speed of a driven element is characterised in that the governor permits the clutch to be engaged also when the speed of the driving element is greater than that of the driven element. In the construction shown in Figs. 1, 2 and 5 the usual clutch pedal 16 is operated by a servo-motor 22 connected by a pipe 26 and a valve 24 either to the induction pipe 14 of the vehicle engine to disengage the clutch or to the atmosphere to allow the clutch to engage. The valve 24, Fig. 5, when free from outside control, opens the connection to the atmosphere and closes that to the induction pipe under the influence of springs 28, 30, but when the accelerator pedal 42 is depressed to open the throttle 12 the valve rod 40 is moved to the left, the connections are reversed and the clutch is engaged. In order to prevent the valve rod from moving to the left if the driven clutch member is rotating faster than the driving member a clamp 62 in the rod is adapted to be engaged by a lever 56 pivoted at 58 and extending into a casing 44 between two diaphragms 48, 50 these diaphragms forming closure members for fluid chambers 52, 54. The chamber 52 is connected by a pipe 66 to the oil pump 64 of the engine, so that the pressure in 52 is proportional to the engine speed. Similarly, the pressure in 54 is proportional to the speed of the propeller shaft 20, a gear pump 70 taking oil by a pipe 76 from the engine sump, and sending it through a pipe 68, the chamber 54, an adjustable relief valve 84 and a pipe 80 back to the sump. When the vehicle is first started and the lower gears of the gear-box 18 are in use the engine shaft is running considerably faster than the propeller shaft 20, so that the pressure in 52 is higher than in 54 and the lever 56 is swung towards position E. In this position the lever is not in the way of the clamp 62 on the valve rod 40 so that the clutch can be engaged as soon as the accelerator pedal is depressed to open the throttle. When top gear is to be engaged the accelerator pedal is released to disengage the clutch, the top gear is engaged, and, since the propeller shaft 20 is rotating at a fairly high speed the pressure in 54 moves the lever 56 towards D. The valve rod 40 is then prevented from moving to the left to cause the clutch to engage until the accelerator pedal is depressed and has caused the engine speed to increase to such an extent that the pressure in 52 rises and moves the lower 56 back to N. Bv adjusting the relief valve 84 clutch engagement can be arranged to take place when the engine and propeller shaft speeds are the same. In a modification the pump 70 is driven by the driven member of the clutch so that the governing lever 56 is effective on all gear ratios of the gear-box.