VEHICLE AND HYDRAULIC SYSTEM WITH SINGLE PUMP THEREFOR

摘要

A hydraulic system is disclosed for energizing the power steering and various work handling hydraulic load circuits of a lift truck. A single positive displacement pumpe (60) supplies the requirements of the plural load circuits and is driven by a changeable speed prime mover (62). Manually actuable selector means are operatively connected with the load circuits and speed control means are provided for the prime mover. A priority demand valve is connected between the pump (60) and the respective load circuits. When only the power steering circuit is selected, the prime mover (62) is operated in a low speed range, when the lift circuit is selected, the prime mover (62) is operated in a high speed range and when an auxiliary work handling circuit is selected, the prime mover (62) is operated in an intermediate speed range. The prime mover (62) may be either an electric motor or an internal combustion engine.