Method of and apparatus for actuating the torque transmitting system and the transmission in the power train of a motor vehicle

A motor vehicle comprising an engine;

• a transmission shiftable into selected ones of a plurality of gears;
• an engageable and disengageable torque transmitting system in a path for the flow of torque between said engine and said transmission;
• and an operating unit for initiating changes in the extent of engagement of said system and a shifting of said transmission into selected gears to thus effect an automated gear change, said operating unit being arranged to receive a pressurized flowable medium by a hydraulic unit having a pump and an accumulator, said operating unit comprising at least one operating member and said hydraulic unit further comprising valves and hydraulic connections arranged to carry out controlled gear selecting and shifting operations, said operating and hydraulic units comprising a first section in which a proportional valve controls a fluid pressure for shifting said transmission by way of a second operating member and a second valve downstream of said proportional valve is arranged to select the shifting direction, said operating and hydraulic units further comprising a second section wherein a proportional valve controls a fluid pressure for the actuation of said system by means of said at least one operating member and for the selection of a gear by a third operating member, at least one additional valve downstream of said proportional valve in said second section being arranged to initiate the selection of a gear.

A motor vehicle comprising an engine;

• a transmission shiftable into selected ones of a plurality of gears;
• an engageable and disengageable torque transmitting system in a path for the flow of torque between said engine and said transmission;
• and an operating unit for initiating changes in the extent of engagement of said system and a shifting of said transmission into selected gears to thus effect an automated gear change, said operating unit being arranged to receive a pressurized flowable medium by a hydraulic unit having a pump and an accumulator, said operating unit comprising at least one operating member and said hydraulic unit further comprising valves and hydraulic connections arranged to carry out controlled gear selecting and shifting operations, said operating and hydraulic units comprising a first section in which a proportional valve controls a fluid pressure for the torque transmitting system, said operating and hydraulic units further comprising a second section wherein a proportional valve controls a fluid pressure for the actuation of said system by means of one operating member, said operating and hydraulic units further comprising a third section for the selection of a gear by a third operating member, at least one additional valve downstream of one of a hydraulic resistance and a pressure reducing valve in said third section being arranged to initiate the selection of a gear.