Abstract: A self-propelled combine harvester having a mechanically actuated directional control valve for a hydraulic piston-cylinder unit used for driving the cutter bar in an oscillatory manner. A switching bracket is used to axially move the mechanically actuated directional control valve from a first end position to a second end position and from the second end position to the first end position. A latch is used to periodically latch a piston valve stationary. A first plunger and second plunger are alternatively and axially moved by a first spring and second spring. The first plunger and the second plunger alternatively move the valve piston from the first end position and the second position and from the second position to the first position. The valve piston will be released from the first end position or the second end position one end position from which it was arrested or latched.

Abstract: A harvesting machine with a front-mounted harvesting attachment that is pivotable about a shaft running transversely to the direction of travel comprising and capable of lifting when an obstacle is detected that includes a sensing device with at least one double-acting hydraulic piston and cylinder unit, having a first cylinder chamber and a second cylinder chamber, arranged on the harvesting attachment, a control valve associated with the sensing device in such a way that when the sensing device is not operated, the first cylinder chamber is in fluid communication with the second cylinder chamber by a control valve and when the sensing device is operated, fluid communication between the first cylinder chamber and the second cylinder chamber is interrupted by the control valve.

Abstract: A self-propelled combine harvester having a mechanically actuated directional control valve for a hydraulic piston-cylinder unit used for driving the cutter bar in an oscillatory manner. A switching bracket is used to axially move the mechanically actuated directional control valve from a first end position to a second end position and from the second end position to the first end position. A latch is used to periodically latch a piston valve stationary. A first plunger and second plunger are alternatively and axially moved by a first spring and second spring. The first plunger and the second plunger alternatively move the valve piston from the first end position and the second position and from the second position to the first position. The valve piston will be released from the first end position or the second end position one end position from which it was arrested or latched.

Abstract: The present invention involves a harvesting machine with a front-mounted harvesting attachment that is pivotable about a shaft running transversely to the direction of travel comprising and capable of lifting when an obstacle is detected that includes a sensing device with at least one double-acting hydraulic piston and cylinder unit, having a first cylinder chamber and a second cylinder chamber, arranged on the harvesting attachment, a control valve associated with the sensing device in such a way that when the sensing device is not operated, the first cylinder chamber is in fluid communication with the second cylinder chamber by a control valve and when the sensing device is operated, fluid communication between the first cylinder chamber and the second cylinder chamber is interrupted by the control valve.

Abstract: A hydraulic control system for connecting elements, which is particularly applicable for an externally engaged clutch on an engine, comprises a pump for producing an oil stream, a distributing valve for determining the flow path of the oil stream, a throttle serving as a metering orifice and inserted in a flow path causing a pressure gradient in the oil stream, a regulating valve connected by supply and return pipes to the flow path of the first throttle upstream and downstream of the throttle, which has a regulating piston acted upon by the higher oil pressure and displaceable against a spring force, a control groove provided on the regulating piston which operates by a ring groove arranged between the piston chamber and the regulating valve with clutch pipe and tank pipes, a second throttle serving as a time orifice and inserted in an output pipe proceeding from the end region of a spring chamber towards the return pipe and adjustable to the closing time of the clutch and a pressure relief output which proc

Abstract: A control (27)is disclosed which may be used as an automotive drive control for a variable displacement hydrostatic pump (11). The pump displacement is controlled by servos (37, 39) by control pressure from a charge pump (21). As a pedal (P) of a vehicle engine (E) is depressed, an increasing pressure differential across a fixed orifice (79) moves a control spool (73) to port control fluid to a first servo port (A). If engine speed becomes excessive, or in response to an external pressure signal (121) representing another vehicle condition, the control spool (73) is moved to a position (FIG. 5 )in which control pressure is ported to a second servo port (B), thus positively reducing the displacement of the pump (11).