| 摘要 |
<p>Two steerable wheels (30, 31) are coupled by a link (26) and operated by hydraulic actuators (12 and 13) with head chambers connected to a directional control valve (38) controlling the supply of hydraulic fluid from a pump (34). The valve (38) is positioned in accordance with the pressure difference between control lines (48, 49) connected to a manually operated metering pump (50). Feedback chambers on the rod sides of the pistons (14, 15) in the actuators (12, 13) are connected to the control lines (48, 49). In order to overcome problems arising from different rates of flow into and out of the feedback chambers, the control lines (48, 49) are connected by a compensating valve (54) which bleeds off pressure from either control line (48,49) when the pressure difference between the lines becomes too great.</p> |
