Abstract: A clutch control system for the automatic control of a motor vehicle clutch which connects an engine with a gearbox under the control of a driver-operated gear ratio selector lever. The control system controls both initial clutch take-up on starting of the vehicle, clutch re-engagment following each ratio change, clutch disengagment on movement of the gear selector lever to change the operative ratio of the gearbox, and clutch disengagment on coming to rest, etc. of the vehicle. Additionally the clutch control system includes an anti-baulking routine which is enabled if the gear selector lever is in its neutral position and which when enabled allows engagement of the clutch by increasing the engine speed above an idle level.

Abstract: A clutch control system having an engine speed sensor (26) for monitoring the speed of an engine (10), a clutch actuation sensor (34) for monitoring the operation of a clutch slave cylinder (22), a throttle position sensor (30) and a control unit (36) receives signals from the sensors (26, 34, 30) and determines when clutch control is required. When it is, the control unit switches to a reference mode in which, in a continuous closed loop operation, an engine speed signal Ve is compared to a reference speed signal Vr and the clutch is engaged or disengaged slightly to make the engine speed approach the reference speed.

Abstract: A clutch control system for a motor vehicle comprising a clutch position sensor (34), a throttle position sensor (30), gear selector (24), clutch actuator (22), and a control means (36, 38). When the gear selector (24) initiates a gear change the clutch actuator (22) holds the clutch in a partially disengaged position until the vehicle throttle signal (Vt) falls below a predetermined value (TL) which is based on the friction clutch driven plate speed in the clutch was disengaged and the driven plate was being rotated by the speed of the vehicle.

Abstract: A motor vehicle power line comprises a combustion engine (8), a gearbox (10) and an electronically controlled clutch (20). The engine throttle (84) is actuated by an electric motor (92) controlled by the electronic control (48) usually in response to throttle demand signals. A manual move of the gear shift level (16) causes the clutch (20) automatically to disengage. When a new gear is engaged the clutch (20) is automatically re-engaged. When the gear change is an up-change the clutch (20) is automatically disengaged to lower (102) its torque transmitting capacity (C) from a maximum (C1) to zero. As the gear change progresses the new gear starts to be engaged causing the speed (B) of the gearbox input shaft (14) and clutch driven plate (32) to drop (110) to (Sn). While this is happening control (48) takes full control of the throttle and closes it. The disengaged clutch and closed throttle causes the engine speed (A) to decelerate (114).

Abstract: A motor vehicle having a transmission comprising a clutch (14), a clutch control (18, 20) and a change-speed gearbox (12). The gearbox (12) has a plurality of mutually exclusively engageable gear ratios any desired one of which can be engaged by a manually operated gear lever (16) which comprises a shaft (33) pivoted at (34) and a hand knob (42) on a tube (40) rockably pivoted in force relatively to the shaft (33), a signal is sent to the clutch control (18, 20) causing automatic disengagement of the clutch (14). Further manual force on the tube (40) pivots the shaft (33) in direction (A) or (B) to the opposite side of a gear shift pattern. The clutch control (18, 20) receives a signal (54') that a new gear ratio has been engaged and automatically reengages the clutch (14).

Abstract: A control system for a rotary transmission for controlling pressure during speed ratio changes. The system includes a pump for delivering fluid under pressure which fluid selectively engages speed ratio selectors to enable the drive to be transmitted through the transmission. The system also embodies a regulator for regulating the fluid pressure in response to a throttle controlled torque demand signal. The system also includes sensors arranged to provide a signal to indicate the state of a speed ratio as well as a command signal to effect a change in the speed ratio.

Abstract: A friction clutch driven plate has an annular friction facing with a back surface in contact with an opposed surface of a friction facing carrier.Circumferentially spaced recesses are provided in the back face of the facing so as to relieve the back surface of the facing to allow portions of the friction surface of the facing to yield under axial load on engagement of the driven plate against a drive member.

Abstract: A ratarder for a power transmission shaft comprises a liquid immersed coupling between the shaft and a drag member, the drag member being normally entrained to rotate with the shaft by viscous drag in the coupling. A dry brake mechanism, having a frictional drag greater than that of the coupling, is provided to restrain the drag member for relative movement to take place in the coupling. In the embodiments shown, the coupling comprises a friction disc pack alternately connected to the shaft and the drag member, the brake mechanism firstly restraining the drag member and subsequently shifting it axially to engage the friction disc pack.The coupling is suitable for use in heavy motor vehicle transmission systems.