| 摘要 |
A brake assembly (10, 210, 310, 410) with a master cylinder totally integrated into a brake booster. A housing for the brake booster has an interior separated by a movable wall (30, 30') to define first (32, 32') and second (34, 34') chambers. The movable wall (30, 30') has a hub member (46) for retaining a control valve (50). The control valve (50) is responsive in a first mode of operation for connecting the second chamber (34, 34') with the first chamber (32, 32') to communicate a first source of fluid (vacuum) to the second chamber (34, 34') and in a second mode of operation, after terminating communication of said first source of fluid, for connecting the second chamber (34, 34') with a second source of fluid (atmospheric air). With the first source of fluid in the first chamber (32, 32') and the second source of fluid in the second chamber (34, 34') a pressure differential acts on the movable wall (30, 30') to develop an actuation force for pressurizing fluid to effect a brake application. End means (18) secured to the housing has a projection (17) located in the first chamber (32, 32') with a plurality of passages (98, 100) for communicating fluid to a brake system. A cylindrical member (60, 260, 360, 460) has a blind bore (74) that extends from a first end (70, 264, 362) toward a second end (72, 266, 366). The cylindrical member (60, 260, 360, 460) slidably and sealingly engages the end means (18) to connect the blind bore (74) with the plurality of passages (98, 100). A reaction member (120) is located between the hub member (46) and the cylindrical member (60, 260, 360, 460). A resilient arrangement (80, 388, 390, 488, 490) urges the cylindrical member (60, 260, 360, 460) toward the reaction member (120) to define pressurizing chambers (84, 86, 284, 286, 384, 386) in the blind bore (74). The actuation force acts through the reaction member (120) to initially move the cylindrical member (60, 260, 360, 460) into engagement with the end means (18) to terminated communication with a source of compensation fluid and establish specific flow paths between the blind bore (74) and the plurality of passages (98, 100) connected to the brake system. After overcoming the force of the resilient arrangement (80, 388, 390, 488, 490), the cylindrical member (60, 260, 360, 460) continues to move and pressurizing fluid in the pressurizing chambers (84, 86, 284, 286, 384, 386). This pressurized fluid is communicated through the passages (98, 100) to effect a brake application.
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