Robert Boschgmbh

Wilhelm Zirps

Wolfgang Schuller

Wolfgang Maisch

Robert Mergenthaler

Dieter Weigle

Juergen Gruber

Uwe Schaub

Hugo Preun

Georg Reick

Martin Urban

Pressure-medium-traversed piston of a reciprocating piston pump

Brake pressure control system for braking systems

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. The reciprocating piston pump can for instance be used in vehicle brake systems to pump brake fluid.

Reciprocating piston pump

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.

Radial piston pump or motor having pressure zones on the control tap for

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.

Device for anti-skid brake system

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.

Hydraulic high-pressure pump for a vehicle brake system

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.

Master brake cylinder suction refill valve

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.

Re-aspiration valve for master brake cylinders

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.

Hydraulic brake booster with anti-skid master cylinder plunger stop

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.

Brake equipment for a hydraulic vehicle brake system

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. Thereby the mower table automatically lowers with a preselected ground bearing force or selectively without the ground bearing force.

Hydraulic lifting device for harvesting machines

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.

Control valve

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. A throttle gap between the control slide and the housing will assure removal of any air contained in the pressure fluid and a further throttle gap formed between an end face of the control slide and a disc attached thereto serves to catch any foreign particles in the pressure fluid which will be flushed away after moving of the control slide away from its seat.

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 maintained constant.

Pressure valve

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.

Growing community of inventors

Hemmingen, Germany

Wilhelm Zirps