| 摘要 |
<p>A closed-center hydraulic servo apparatus (10) includes a closed-center valve device (112) which is coupled to an input member (60) to control the communication of fluid among a fluid pressure source (12,14), a fluid reservoir (36), and a fluid pressure responsive device (a vehicle brake) (16) in response to movement of the input member (60). The coupling (158, 160) between the closed-center valve device (112) and the input member (60) provides a movement ratio therebetween which is greater than unity. As a result, the inherent deadband (D) of the closed-center valve device (112) is reduced by the inverse of the movement ratio to a level (d) which is sensible to an operator at the input member (60). Particularly for use in automotive vehicle hydraulic braking systems. (Figure 1)</p> |
