| 摘要 |
<p>1533902 Hydrostatic transmission control O & K ORENSTEIN & KOPPEL AG 17 Sept 1976 [17 Sept 1975] 38604/76 Heading F2W In a hydrostatic transmission for the drive wheels of a fork-lift truck, in which an hydraulic motor 5 is connected to a variable displacement axial piston pump 4 in drive connection with a motor 1 and in fluid connection with a make-up pump 3 through non-return and other valves, the displacement of the pump 4 for forward and reverse drive of the vehicle is controlled by a spring biased, hydraulically operated servo 24 which is connected to a manually operated reversing valve 18 by way of a double throttle valve arrangement 20, 26 in which some of the throttles are adjustable in accordance with the loading of the vehicle to restrict the rate of change of displacement of the pump 4 in accordance with the vehicle loading. In operation, the throttles permit adjustment of the pump 4 such that for forward and reverse drives of the truck, respectively, deceleration and acceleration of the truck are controlled in accordance with its actual loading. An hydraulic braking circuit for the vehicle comprises a manually controlled diaphragm device 39 between the high and low pressure lines 17, 28 of the pump control circuit so that when the vehicle brake is operated, the control pressure supply to the double throttle valve arrangement 20, 26 is reduced thereby reducing the displacement of pump 4.</p> |
