Control valve

Abstract

The invention relates to a control valve for the control, independently of a load, of a hydraulic consumer with a distributing slide valve to control the direction of movement and the speed of movement of the consumer and a throttle valve associated with the distributing slide valve. The throttle valve, when there is a connection of a pump with the consumer, can be pressurized toward an open position by the pressure downstream of the throttle point of the distributing slide valve, and toward a closed position by the load pressure of the consumer and by a spring. The invention teaches that the object of providing a control valve that easily makes possible a restriction of the quantity of hydraulic fluid flowing out of the consumer to a reservoir and thus a control of the speed of movement of the consumer in the discharge direction independently of the load, can be accomplished if, when the consumer is connected with a reservoir, the quantity of hydraulic fluid flowing out of the consumer is restricted by the throttle valve. In one embodiment, when the consumer is connected with the reservoir, the throttle valve can be pressurized toward the closed position by the pressure upstream of the throttle point of the distributing slide valve, whereby the pressure acting in the direction of the closed position of the throttle valve can be set and varied by a valve device that generates a differential pressure.

Dependencies are inferred from the claim text.