| 摘要 |
<p>A hydraulic booster for vehicle, includes: a cylinder body (2) having a cylindrical bore; a piston (19) slidably fitted into the cylindrical bore; a pressure-servo chamber (29) formed at one side of the cylindrical bore by the piston; a valve hole (64) made in the side of the pressure-servo chamber in the piston; a pressure supply path extending into the valve hole and communicating with a fluid pressure source; a pressure discharge path extending into the valve hole and communicating with a pressure-relieving source; an input member (9) passing through the pressure-servo chamber and entering the valve hole; a pressure-supply valve (E) arranged in the valve hole for opening and closing the path between the pressure supply path and the pressure-servo chamber in response to the movement of the input member; a valve (G) arranged in the valve hole for opening and closing the path between the pressure discharge path and the pressure-servo chamber in response to the movement of the input member; a reaction chamber (88) in which the input member is able to receive the pressure-servo chamber side pressure of the pressure-supply valve in a direction against the input direction of the input member; and a valve apparatus (A) arranged in a path to the reaction chamber and preventing fluid pressure from transmitting into the reaction chamber at a lower pressure than a predetermined pressure. In the hydraulic booster, a by-pass path is arranged for connecting the pressure-servo chamber with the pressure-discharge valve without passing through the reaction chamber. <IMAGE></p> |
