| 摘要 |
<p>A fluid pressure operated vehicle braking system includes a control valve assembly comprising an inlet and outlet, a normally-open valve having a valve member movable in response to a predetermined inlet pressure to control the flow of pressure fluid between the inlet and the outlet, and a stepped piston subjected to a biasing force dependent upon the vehicle loading and operable in response to both the inlet pressure and the biasing force to reduce the outlet pressure after the predetermined inlet pressure is attained.</p> |
