| 摘要 |
PROBLEM TO BE SOLVED: To suppress the positional displacement of a fastening piston in a non-fastened state, and to improve the compactness and responsiveness of the fastening control of a brake by constantly utilizing output pressure belonging to a stable output region of a hydraulic control valve, in the brake of a transmission.SOLUTION: In a transmission having a fastening hydraulic chamber 65 which is supplied with hydraulic pressure outputted from a hydraulic control valve 120, and a fastening piston 69 having a pressure-receiving part 69a which faces the fastening hydraulic chamber 65, a brake 60 which connects and disconnects a rotating element 63 and a case 5 further comprises a back pressure chamber 66 which is arranged while adjoining a side opposite to the fastening hydraulic chamber 65 with the pressure-receiving part 69a sandwiched therebetween, and oil passages 122, 132 which introduce the hydraulic pressure outputted from the hydraulic control valve 120 to the back pressure chamber 66. A relief valve 130 for outputting output pressure to the back pressure chamber 66 side when the output pressure of the hydraulic control valve 120 is lower than prescribed pressure P1, and outputting the prescribed pressure P1 to the back pressure chamber side when the output pressure is not lower than the prescribed pressure P1 is arranged on the oil passages 122, 132.SELECTED DRAWING: Figure 3 |
