| 摘要 |
PURPOSE:To improve the reliability by making control valves to control the communication between a transformer chamber and the atmosphere into plural control valves. CONSTITUTION:A brake booster 31 for control is composed of a negative pressure chamber 31a to which a suction negative pressure of an internal combustion engine is led in, a transformer chamber 31b to which a suction negative pressure and the atmosphere are led in adequately, and a master cylinder 31c to convert the differential pressure between the negative pressure chamber 31a and the transformer chamber 31b into an oil pressure, and the oil pressure generated by the master cylinder 31c is fed to brake mechanisms 6 to 9 of the wheels as a brake oil pressure. The negative pressure fed to the transformer chamber 31b is controlled by a negative pressure leading-in valve EACV3. And the atmosphere led in to the transformer chamber 31b is controlled by two atmosphere leading-in valves EACV1 and EACV2. |
