Device for controlling the speed of a hydraulic motor

摘要

The device for controlling the speed of a hydraulic motor for driving an auxiliary unit in a motor vehicle has, in the delivery line (16) of the pump (10), a pressure compensator (25) which is assigned a variable metering orifice (26). Via the pressure compensator, the pressure-medium flow metered in flows to the hydraulic motor (17) independently of the speed of rotation of the pump. When no power is required at the hydraulic motor, only a very small flow of pressure medium flows to the latter. This small flow of pressure medium is controlled by the metering orifice (29) and the pressure compensator (25) independently of the load-pressure condition in the load. If the pressure at the load increases due to an adjustment to a pressure regulator on the hydraulic motor, the pressure-dependent metering orifice (26) connected in parallel opens and increases the supply of pressure medium to the hydraulic motor, in particular as a function of the level of the system deviation. In this way, a simple and economical means of controlling the hydraulic motor is obtained. <IMAGE>