| 摘要 |
1,180,544. Change-speed control. FRANCAISE DU FERODO S.A. 19 March, 1968 [24 March, 1967; 15 June, 1967], No. 13282/68. Heading F2D. In a vehicle change-speed gear with fluid pressure servos controlling ratio-establishing friction clutches or brakes provision is made through a by-passing valve to supply a reduced servo pressure when a gear change is made from neutral to start the vehicle. In the arrangement shown a pump 80 supplies pressure liquid to the servos 83 through a line 82 provided with a regulating valve 84 and also supplies a torque converter or coupling 87 through a second line 85 and regulating valve 86. A cushioning valve 93 is mounted between the pump outlet 94 and by-pass lines 94a, 97, communication between the lines being controlled by a second valve 98 which in the neutral setting shown allows free communication, but when moved to the right when a gear change is initiated cuts off communication. In neutral the valve 93 is held open by a spring 96, and when gear is engaged to start the vehicle, although valve 98 is closed the reduced output of pump 80 at idling speed is insufficient to cause a pressure drop to close valve 93 so that the reduced pressure is supplied to servo line 82 and starting is effected without shock. When a normal gear change is made the pressure drop closes valve 93 and high pressure is supplied through line 82. A modification, Fig. 9 (not shown), includes in association with valves 85, 93 a solenoid valve (34) operated by movement of the gear lever (13). |
