| 摘要 |
<p>An integral power steering assembly of the type which includes a housing defining a power cavity with a rack-toothed piston movably supported in the cavity and in meshing engagement with a sectored gear which in turn rotates an output shaft. A control valve is supported by the housing for controlling the flow of pressurized fluid from a source to the cavity on one side or another of the piston and the return flow from the opposite side of the piston whereby the piston is moved in alternative and opposite directions. An input shaft forms a part of and controls the control valve. Mechanical connections also interconnect the input shaft and an output shaft for rotating the output shaft in response to rotation of the input shaft in the event of the lack or loss of fluid pressure to move the piston hydraulically. These components are in the form of an integral or unitized package which may be attached to a vehicle as one unit. The improvement comprises a bleed valve establishing communication between the power cavity in which the piston is disposed and the return line from the control valve for automatically bleeding air from the hydraulic power cavity in which the piston is disposed. The bleed valve includes a valve member slidably disposed in a passage and normally held away from a valve seat by a spring. The valve member allows air to pass thereby but as the hydraulic fluid pressure increases, the valve member will be moved against the seat to prevent the flow of hyraulic fluid from the power cavity to the return.</p> |
