Abstract: The invention deals with a magnetically actuatable valve, in particular a hydraulic valve, with a piston guided inside of a body for establishing at least one flow-through connection, with the piston being effectively connected with two electromagnets with electric junctions and disposed on both sides of the basic body, and with the electric connection of the electromagnets being established by a sole central junction plug which is electrically connected and mechanically fixed with contact pins disposed on the electromagnets.

Abstract: Radial piston machine as a fluid pump or fluid motor comprising an inner valving trunnion, an outer cam ring and at least a cylinder block arranged therebetween and having reciprocating pistons, which tilt when the cylinder block rotates. The pistons have spherical heads and crowned piston rings along the biggest diameter or equator in order to create each an oblique sealing plane when the respective piston is tilted. Pressure in each chamber limited by said oblique sealing plane will give rise to a direct transformation of torque and fluid pressure. The valving trunnion has enlarged sealing fields to get a precompression of the fluid between high and low pressure fluid areas in order to avoid excitation of noise. The machine design can be for constant or variable displacement. In case of variable displacement, the sinusoidal curve of piston travel is adjusted for a variable preceeding angle (.epsilon.) by adding a constant eccentricity (c) so that the angle of the separation (.tau.

Abstract: A gear pump or motor comprises a pair of rotary gears which are in external meshing engagement with each other. A thrust plate is pressed against the side faces of the gears by means of a plurality of pressure areas which are produced by means of a sealing and compensating unit. The unit is urged piston-like by virtue of fluid pressure chambers against the back of the thrust plate to engage it against the gears. Depending on the direction of rotation of the gears of the machine the pressure areas define the general configuration of a 3 or a .epsilon..

Abstract: A steering power-assistance pump of vane type includes a combined flow control and pressure relief valve. When the steering valve of the steering arrangement shuts off the flow of oil, the output of the pump is converted into heat within the pump which accordingly suffers a substantial rise in temperature. The rotor of the pump and the cam ring with which the rotor vanes co-operate are combined with a pressure plate and a wear plate on respective sides of the rotor to form a unit which is displaceable in the axial direction of the pump against the force of a compressible sealing means for sealing off inlet ducts relative to a pressure chamber behind the pressure plate. The unit is thus displaced against the force of the compressible sealing means, as a result of thermally induced deformation of the housing portions of the pump. The wear and pressure plates have coatings of bearing metal on their surfaces which co-operate with the rotor, to provide better anti-friction properties.

Abstract: A hydraulic pump with a falling characteristic curve in respect of the output flow relative to the pump speed. A flow control valve (40) has a spool (41) with a hollow (50) extension portion (49), and an annular chamber (52) with two control edges (53, 56) which co-operate with the valve output duct (38) and a relief duct (19) to form restrictor means which are in opposition to each other. The valve output duct (38) and the relief duct (19) are disposed substantially radially with respect to the spool.

Abstract: A hydraulic rotary vane pump comprises a flow control valve with a venturi throat disposed upstream thereof whereby the entire delivery flow from the pump passes through the venturi throat. The flow control valve is operable to control the amount of fluid flowing to the delivery outlet of the unit, under the influence of the pressure drop at a restrictor throttle in the form of a bore extending from the throat transversely with respect to the axis thereof. The angle between the axis of the venturi throat and the axis of the bore is between 90.degree. and 150.degree. depending on the degree to which the characteristic of the outlet flow produced is intended to drop off.

Abstract: A main pump (rotary vane pump 1) and a secondary pump (radial piston pump 2) are driven by way of a common shaft (3), a cam ring (30) being used to drive the secondary pump. The cam ring is coupled to the shaft (3) by way of a shear pin (33). If the auxiliary pump locks, the shear pin fractures and the cam ring (30) can rotate relative to the shaft (3). In that case, the fracture portions of the shear pin (33) are driven into their respective bores (34, 35), thereby avoiding excessive friction and overheating. Therefore, the main pump can continue to operate in spite of the failure of the auxiliary pump.

Abstract: A steering assistance pump includes a temperature sensor valve which communicates with an inlet duct of the pump by way of an additional, normally closed outlet passage. When a pressure relief valve responds, upon blocking of the servo steering means, the temperature of the hydraulic fluid in the system increases to such a degree that it exceeds the limit value of the temperature sensor valve. The valve thus opens to cause the pilot control pressure in the control chamber of the pressure relief valve to be reduced, whereby the pump pressure itself is also reduced.

Abstract: In a rotary vane pump having a normally vertical suction feed flow passage (17a, 17b) which opens tangentially into a horizontal, elbow-bent feed passage (18a, 18b) and a discharge passage (19a, 19b), the direction-changing portion is formed by a plug-like insert (51) which is pressed into a stepped bore (61). The insert (51) comprises erosion-resistant material.