JPH0430351U

JPH0430351U -

Info

Publication number: JPH0430351U
Application number: JP7129590U
Authority: JP
Priority date: 1990-07-03
Filing date: 1990-07-03
Publication date: 1992-03-11

Description

[Brief explanation of the drawing]

第１図は本考案の一実施例における変速機の制
御用油圧回路の回路図、第２図は従来の変速機の
制御用油圧回路の回路図である。１……ポンプ（作動油供給源）、６……圧力感
知弁、１７……インチング弁、１７ｇ……ブレー
キペダル（インチング操作部）、１９……速度切
換弁、２１……蓄圧器、３９……第１のピストン
、４０……第２のピストン、４１……第１の油室
、４２……第２の油室、４３……ばね、Ｃ１，Ｃ
２，Ｃ３，ＣＦ，ＣＲ……クラツチ（摩擦機構）
。 FIG. 1 is a circuit diagram of a hydraulic circuit for controlling a transmission according to an embodiment of the present invention, and FIG. 2 is a circuit diagram of a conventional hydraulic circuit for controlling a transmission. DESCRIPTION OF SYMBOLS 1... Pump (hydraulic oil supply source), 6... Pressure sensing valve, 17... Inching valve, 17g... Brake pedal (inching operation part), 19... Speed switching valve, 21... Pressure accumulator, 39... ...First piston, 40...Second piston, 41...First oil chamber, 42...Second oil chamber, 43...Spring, C1, C
2, C3, CF, CR...Clutch (friction mechanism)
.

Claims

[Scope of utility model registration request]

A speed switching valve for selectively supplying hydraulic oil to a plurality of friction mechanisms for shifting, a forward/reverse switching valve for selectively supplying hydraulic oil to a plurality of friction mechanisms for forward/reverse switching; A pressure sensing valve that is interposed between the speed switching valve and the forward/reverse switching valve and the hydraulic oil supply source and reduces the rising speed of the oil pressure on the outflow side when the oil pressure on the outflow side is less than a set value, and this pressure sensing valve. By operating an inching operation section interposed between the valve and the forward/reverse switching valve or the speed switching valve, hydraulic oil is supplied to the oil chamber of the friction mechanism selected by the forward/reverse switching valve or the speed switching valve. A hydraulic circuit for controlling a transmission including an inching valve for cutting off supply, comprising first and second oil chambers, a first piston whose pressure-receiving surface faces the first oil chamber, and the first oil chamber. A pressure receiving surface having a larger area than the pressure receiving surface of the piston faces the second oil chamber, and a surface opposite to the pressure receiving surface is spaced from a surface opposite to the pressure receiving surface of the first piston. a second piston facing each other, and a surface of the first and second pistons opposite to the pressure-receiving surfaces, and biases the first piston and the second piston in opposite directions. A pressure accumulator is provided with a spring, and hydraulic oil is supplied to a first oil chamber of the pressure accumulator via the pressure sensing valve to accumulate pressure when the hydraulic pressure downstream of the pressure sensing valve is below a set value. By this, the rising speed of the hydraulic pressure on the downstream side of the pressure sensing valve is reduced, and when the inching operation section is operated, hydraulic oil is supplied to the second oil chamber of the pressure accumulator through the inching valve to accumulate pressure. When the operation of the inching operation section is released, the hydraulic oil stored in the second oil chamber of the pressure accumulator is selected by the forward/reverse switching valve or the speed switching valve via the inching valve. A hydraulic circuit for controlling a transmission, characterized in that the hydraulic circuit is configured to supply oil to an oil chamber of a friction mechanism.