| 摘要 |
PURPOSE:To reduce the generation of a speed change shock by a method wherein a hydraulic servo means to friction-engage the friction engaging element of a forward reversing shifting mechanism is actuated by means of a throttle pressure from a throttle valve responding to a throttle opening. CONSTITUTION:A line pressure by a pressure regulating valve 30 is further regulated to a relatively low pressure by a throttle valve 40 actuated by a throttle cam 41 to drive a hydraulic servo means 690 of a forward reversing shifting mechanism. Since a friction engaging element is gently friction-engaged by means of the hydraulic servo means 690, when a shift range is shifted by a manual shift valve 65, a shock occasioned by control of speed change is reduced. Further, since the pressure of working oil is low, a load on sealing of the hydraulic servo means 690 of the forward reversing shifting mechanism and a load on sealing of a hydraulic circuit 2 are decreased. This constitution enables reduction of the generation of a shock occasioned by control of speed change. |
