| 摘要 |
<p>A hydraulic power boost mechanism for a vehicle braking system includes a manually operated control valve means and a power piston sealingly positioned in a housing for reciprocal movement therein from a released position to an applied position under the influence of fluid boost pressure developed by manipulation of said valve means and acting in a chamber to which one end of the piston is exposed. Operatively connected to the boost mechanism is a pressure limiting device which is responsive to a predetermined pressure in the chamber for inhibiting further pressure rise in the chamber so that the power piston will not generate excessive pressures in the braking system via the master cylinder.</p> |
