| 摘要 |
PROBLEM TO BE SOLVED: To prevent clogging by providing a valve device as a throttle valve having the largest flow surface normally, and permanently connecting a booster chamber to a pressure duct. SOLUTION: On the inside of a brake booster 1, a booster pressure space 15 is partitioned by a booster piston 14, and the booster pressure space 1 is substantially composed as a circular space. A duct is introduced from the space 15 to be connected to a throttle valve 17. The throttle valve 17 is a needle throttle valve, for example. By means of a pump 19a, pressure medium sucked from a reservoir tank 18 flows through a pressure conduit 31, the pipeline, and the throttle valve 17 to go through a circulation conduit 16, 1 to be returned to the reservoir tank 18. The throttle valve 17 of this type constantly has a large throttle cross section, so clogging of the throttle valve 17 and undesired brake action caused by that can be avoided. |
