| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To reduce manufacturing costs by giving a plurality of sealing functions to a seal member, and reducing the number of seal members for sealing gaps between a drain part of a master cylinder, a low-pressure chamber of a booster, and atmosphere for simplifying a structure. <P>SOLUTION: When a piston is actuated by a booster attached on a booster attachment face of a cylinder body, working fluid is supplied to a brake system from a hydraulic chamber of the cylinder blocked by a liquid-tight seal member. An annular compound seal member is accommodated in an inner peripheral seal step part formed by enlarging a diameter of an opening of the cylinder opened to a booster attachment face. The gap between the drain part and a constant pressure chamber of the booster after the liquid-tight seal member is sealed by sliding a slide seal part of the compound seal member in slidingly contact with the piston; the gap between the constant-pressure chamber and the atmosphere is sealed by bringing an airtight seal part into a front end face of the booster; and the gap between the drain part and the atmosphere is sealed by bringing a fixed seal part into contact with an inner periphery of the inner peripheral seal step part. <P>COPYRIGHT: (C)2004,JPO</p> |
