| 摘要 |
<p>A vehicle hydraulic power steering system is provided, having a diversion valve to facilitate high speed towing with the power steering system pump inactive. A tow bar has the tie rods of two dirigible wheels connected to it, and is swung in a horizontal plane in the power steering mode by a linear hydraulic motor: the hydraulic motor is controlled by a steering valve supplied with pressure fluid from a pump. In the towing mode, the tow bar drives the hydraulic motor as a pump, and a diversion valve permits circulation of hydraulic fluid between the opposite sides of the piston of the hydraulic motor and a reservoir, through restricted passages in the diversion valve to provide damping of dirigible wheel motion.</p> |
