Abstract: This invention is directed to a closing member of an inlet valve of a pressure-medium-traversed piston of a reciprocating piston pump. The closing member is disposed as fully as possible in the piston to minimize the dead air space. The piston has a longitudinal bore in which a stem engages the closing member, which stem emanates from a valve disk. The stem is embraced by an at least approximately frustoconical helical compression spring acting as a closing spring. This is held, with an end segment of smaller diameter, non-twistably against the stem. A shoulder of the longitudinal bore is located on the valve seat side and exhibits at least one cross-sectional alteration for the screw-like action upon the end segment of larger diameter of the closing spring. The closing spring is thus able to be sunk into the longitudinal bore and biased in place. The reciprocating piston pump can be used, for example, for slip-regulated braking systems of motor vehicles.

Abstract: A brake pressure control system for braking systems of a vehicle with anti-locking and drive slip control in which there is at least one expansion chamber provided between the wheel brake cylinders and the recirculating pump. The expansion chamber includes an inlet and an outlet on the same end with a piston having a closing mechanism thereon that is spring forced to seat the closing mechanism on a seat at the outlet. The valve seat is reduced in size compared with the piston and the spring is in a chamber which is open to the atmosphere. Due to the valve seat being reduced in relation to the area of the piston located in the expansion chamber, a steep closing force gradient is achieved, since even small pressure differences result in large closing force differences, so that the opening and closing pressures lie close together. Based on this additional closing mechanism, provided on the expansion chamber, the requirement for a separate valve for brake pressure control is no longer required.

Abstract: The invention is directed to improving the performance of a reciprocating piston pump in terms of noise. The reciprocating piston pump has a drive shaft, which has a circular cylindrical swash member, which is set at an acute angle (.beta.) to the longitudinal axis (O) of a pump and has a circumferentially disposed roller bearing ring. A pump piston, with its end face embodied as part of a spherical surface, engages the circumferential face of the roller bearing ring of the swash member. The longitudinal axes (O, P) of the drive shaft and pump piston extend in the same plane and intersect at right angles. The longitudinal axis (O, T) of the drive shaft and swash member are also offset from one another. Because of this configuration, a pumping phase that is considerably longer than the intake phase during one pumping cycle is attained. Changes in pressure andd force therefore proceed more slowly in the lengthened pumping phase, which improves the noise performance of the reciprocating piston pump.

Abstract: In an apparatus having a radial piston device, in particular a radial piston pump or motor or the like, a pump body rotates around a control tap. Radially moving pistons are supported in the pump body and with the control tap define a pumping chamber for a fluid medium. This pumping chamber can be connected to both an intake bore and a pressure bore. Further, pressure zones are found on the jacket face of the control tap, between the control tap and the pump body, so that as a result the pump body is mainly supported by hydrostatic forces. These pressure zones are intended to comprise intersecting conduits, with segments of the jacket face remaining between them.

Abstract: The invention relates to a device for a hydraulic unit, in particular in anti-skid systems for vehicle brake systems, which has a radial piston pump. The eccentric driven by a drive shaft in the pump meets pump pistons also located in the pump, usually in the region of high stroke variation speed. An resultant mechanical and hydraulic vibration, which causes noise and annoying movement at the brake pedal, is counteracted according to the invention in that a resilient intermediate element is disposed between the pump pistons and the eccentric element, and the eccentric is driven via a torsionally elastic coupling.

Abstract: The pump having a housing with a bore for receiving a pump cylinder having a pump piston, which is drivable by a cam. An outlet valve housing is disposed, coaxially with the cylinder, in an enlarged portion of the bore. An annular chamber formed thereby encompasses the outlet valve and is closed off by a cap. The pump piston cylinder, the outlet valve and the cap are retained by a closure screw in the pump housing, which screw is screwed into the bore portion. In combination with a pump outlet bore embodied as a throttle, the annular chamber acts as a damper chamber for the brake fluid that in this type of pump is pumped discontinuously. Because of the damper chamber and pump outlet bore, pressure vibrations of the brake fluid reduced, and an impetus toward vibration of the vehicle body during a pump operation is avoided, so that noise generation in the interior of the vehicle is largely suppressed.

Abstract: A suction refill valve for a master brake cylinder which is suitable for use in brake systems having brake slip control. The refill valve has a sealing element, made from an elastic material, which is annular and is acted upon on virtually all sides by the pressure arising in the work chamber of the brake cylinder. In combination with a valve opening embodied as an annular gap, the suction refill valve can open at relatively low force, even when the brake pressure is high.

Abstract: A master brake cylinder including a re-aspiration valve which is disposed as a central valve in pistons of the master brake cylinder. The re-aspiration valve has a porous body, comprising porous metal, which forms a flat valve seat at one end. The sealing body of the re-aspiration valve is raised gently from the valve seat even at high ambient pressure, which makes a re-aspiration valve embodied in this way particularly suitable for use in master brake cylinders of brake systems having slip control. Because the porous body comprises porous metal which differs in length from its wall surface at one end to its axis to form a conical void space. The porous body has an axial flow resistance that decreases from the outside wall inward to its axis.

Abstract: A hydraulic vehicle brake system having a brake booster disposed in a housing. The brake booster communicates via an energy supply system with a supply container and via shutoff devices with brake chambers that can be acted upon by plungers via the brake booster. The brake chambers are connected in turn via brake lines and incorporated shutoff valves to wheel brake cylinders of wheel brakes. A stop bushing surrounds the master cylinder piston and has a sleeve, and a spring is disposed between the sleeve and an annular stop integral with the housing. The stop bushing, an inner plunger face and the housing enclose a plunger chamber. In regulated operation, the plunger chamber likewise communicates with the energy supply system via the brake booster and corresponding lines. During normal brake operation the plunger chamber is connected to the supply container via a line connected to a reversible valve.

Abstract: Brake equipment for a hydraulic vehicle brake system which has an actuating assembly and a feed pump secured elastically thereon. The two communicate with one another via at least one suction and pressure line each. To assure an inexpensive, dependable flexible line connection between component parts that move relative to one another, the suction and pressure lines are embodied as housing bores in the assembly and pump housings and for a liquid-tight connection of two successive housings bores at a time extending in the course of the lines in the assembly housing on the one hand and in the pump housing on the other, at least one connecting tube is disposed in two flush bearing bores in the assembly housing and in the pump housing. The connecting tube rests pivotably and longitudinally displaceably in the bearing bores sealing off the bearing bores.

Abstract: A hydraulic lifting apparatus for harvesting machines, the apparatus having a plurality of lifting cylinders connected to the undercarriage of the harvesting machine which support a mower table so that it rests on the ground with a minimal resting weight, and also having energy storing tanks to provide different suspension of the mower table. To accomplish this a hydraulically actuatable stop valve is located in a first circuit of working lines running between a distributing slide valve and the lifting cylinders. This stop valve is actuated by a control pressure which is branched from a second circuit of working lines. The second circuit of working lines runs from the distributing slide valve over a pressure relief valve to a reservoir, and is able to be disconnected by a solenoid valve. The stop valve has a valve element with a series of bores through which the pressure set by the pressure relief valve passes through the blocked first circuit of working lines into the lifting cylinders.

Abstract: A pressure valve for heating a pressure medium and maintaining its temperature constant, has a control slider provided with a throttle, a pilot valve influencing a position of the control slider and having a spring-loaded valve member and a valve seat, a thermosensor arranged to sense the pressure medium and to determine throttling of the latter, wherein the thermosensor controls an electromagnet acting upon the pilot valve, and the spring of the pilot valve in the opened position of the valve member is at least partially pretensioned, and upon actuation of the electromagnet and assuming by the valve member the closed position the spring is tensioned to a value corresponding an opening pressure.

Abstract: A control valve for maintaining the temperature respectively the viscosity of pressure fluid passing therethrough substantially constant comprises a control slide provided with a throttle bore and downstream of the control slide a precontrol valve in which an end portion of an element expandable by the temperature of the pressure fluid is arranged. When pressure fluid with a certain pressure is fed through the inlet end of the control valve, the control slide is lifted from its seat and the precontrol valve opens. All of the pressure fluid entering the control valve is passed through various bores and annular gaps along the precontrol valve to the temperature expandable element. When the fluid reaches the desired maximum temperature a bypass for the fluid is created by the expandable element and a control pin actuated by the latter. Thereby the throttle action of the control valve is reduced and overheating of the pressure fluid avoided.

Abstract: The valve for a pressure-medium-operated hydraulic arrangement has a housing provided with an inlet and an outlet, a slide piston located downstream of the inlet and seal-tightly movable in an opening of the housing under the action of the pressure medium entering the same so as to subdivide the pressure medium into a first stream flowing directly to the outlet and a second constant stream, a laminar throttle member located downstream of the slide piston and associated with a spring-biased control member wherein the laminar throttle member and the control member are arranged so that the constant stream flows through the laminar throttle member and generates pressure drop which acts upon the control member against its bias, and the control member subdivides the constant stream into two partial streams which flow to the outlet means and one of which is throttled, whereby the pressure drop between the inlet and the outlet is maintained at a constant level and thereby the viscosity of the pressure medium is maint

Abstract: An electric motor operated adjusting drive has a housing with an opening, a threaded rotary spindle arranged in the housing and having an axis, an adjusting nut arranged on the spindle axially displaceable and non-rotatable, and an adjusting member arranged in the housing and sealed relative to the latter. The adjustment member is actuated by the adjusting nut so as to displace linearly outwardly of the housing through the opening. The adjustment member is formed by a hollow body which is thin-walled and surrounds the threaded spindle. The adjustment member is sealed inwardly relative to the threaded spindle and outwardly relative to the opening of the housing.

Abstract: The control valve for keeping a constant temperature or viscosity of a pressure medium in a hydraulic consumer circuit includes a main control valve provided with a control slider and a preliminary control valve in which a temperature sensitive control element is arranged in such a manner that upon reaching a predetermined temperature of the medium a bypass channel is established between the inlet and the outlet of the valve.

Abstract: The hydraulic lifting device for harvesting machines includes a hydraulic cylinder-piston unit mounted on the wheel frame of the machine and supporting most of the weight of the harvesting apparatus so that the latter abuts against the ground with residual weight only. The cylinder-piston unit is controlled by a multi-way selector valve and a locking valve unit connected in a first working pipeline system. The hydraulic device further includes a pressure limiting valve for setting a reference pressure for the hydraulic cylinder-piston unit, the limiting valve being connected in an additional working pipeline that is branched upstream the limiting valve to a nonreturn valve and therefrom is connected by a direct conduit to a hydraulic accumulator and the hydraulic cylinder-piston unit.

Abstract: A hydraulic control system for distributing pressure fluid to at least two systems, that is a first system including a first pump supplying pressure fluid through a first conduit to a first consumer and a second system including a second pump for supplying pressure fluid to a second conduit, in which a plurality of multiple position valves are arranged, each movable between a neutral position providing free flow of fluid through the second conduit and at least one working position respectively directing pressure fluid to the additional consumer respectively connected to said plurality of multiple position valves. A regulating valve is located in the first conduit and the second conduit is connected by a cross-conduit to the first conduit at a point upstream of the regulating valve therein.

Abstract: A valve for controlling an opening for the passage of fluid into and out of a pressure accumulator has a valve member, which, by the elastically expanding membrane of the pressure accumulator, can be brought against the force of a spring to a closed position. An orifice plate located in the valve housing creates a pressure difference to opposite sides of the plate, and this pressure difference is directed to opposite sides of a piston operably connected to the valve member to thereby bias the latter to the open position during outflow of fluid from the pressure accumulator, to thus prevent a premature movement of the valve member to the closed position.

Abstract: In a control system of the type having a hydraulic cylinder, a piston slidable in the cylinder and dividing the interior thereof into a first and a second pressure chamber, a pressure fluid reservoir, a pump, conduits having a valve interposed therein which is electronically controlled and connects the second chamber with the reservoir or pump, respectively, or block the second chamber, and an auxiliary device for operating the system in the event the electronic control for the valve malfunctions, the invention provides a movable member extending into the second chamber; subdividing means located in the second chamber intermediate the movable member and the piston and subdividing the second chamber into a first and a second compartment, the movable member being operable to shift the subdividing means in the second chamber; and valve means controlling communication between the compartments and of the same with the first chamber, the valve means forming with the piston and with the movable member a follow-up co