Abstract: The invention relates to an hydraulic unit for a motor vehicle brake system which operates according to the feedback principle, for which purpose a low-pressure accumulator is provided between the outlet valves of the wheel brakes and a pump, and the piston of which low-pressure accumulator, in the basic position, disconnects the hydraulic connection between a pressure medium chamber and a connection leading to the pump such that, in the empty state of the low-pressure accumulator, the wheel brakes are reliably disconnected from the suction side of the pump.

Abstract: The invention relates to an hydraulic unit for a motor vehicle brake system which operates according to the feedback principle, for which purpose a low-pressure accumulator is provided between the outlet valves of the wheel brakes and a pump, and the piston of which low-pressure accumulator, in the basic position, disconnects the hydraulic connection between a pressure medium chamber and a connection leading to the pump such that, in the empty state of the low-pressure accumulator, the wheel brakes are reliably disconnected from the suction side of the pump.

Abstract: A piston pump for the hydraulic energy supply in a motor vehicle, comprising a piston that is movably arranged in a stepped bore of an accommodating member that is provided with a closure, the piston carries a seat for an elastic sealing element which accommodates the sealing element with axial play, and with radial elastic preload for the purpose of sealing between piston and cylinder. The seat for the sealing element has a structure which generates forces pointing radially towards a piston axis and expanding the sealing element in a radial direction, and that the structure produces an elastic deformation of the sealing element for an increased and dosed sealing contact pressure between piston and cylinder.

Abstract: A piston pump for the hydraulic energy supply in a motor vehicle, comprising a piston that is movably arranged in a stepped bore of an accommodating member that is provided with a closure, the piston carries a seat for an elastic sealing element which accommodates the sealing element with axial play, and with radial elastic preload for the purpose of sealing between piston and cylinder. The seat for the sealing element has a structure which generates forces pointing radially towards a piston axis and expanding the sealing element in a radial direction, and that the structure produces an elastic deformation of the sealing element for an increased and dosed sealing contact pressure between piston and cylinder.

Abstract: A piston pump (10) for a hydraulic consumer of an electronically controlled vehicle brake system, carries a stepped piston (50, 50?) and centers a sealing assembly (26, 26?) which is retained in an axial direction Ax by a step (52, 52?) on the stepped piston (50, 50?), on the one hand, and is retained by a spring cage (53, 53?), on the other hand. The stepped piston (50, 50?) includes a plane support (54, 54?) for plane support legs (55a,b,c; 55a,b,c?) of the spring cage (53, 53?) The stepped piston (50, 50?) includes radially inwards, with respect to the support (54, 54?), a stepped bore (56, 56?), with the bore (56, 56?) accommodating centering legs (57a,b,c; 57a,b,c?) of the spring cage (53, 53?). Coaxially as well as inside the stepped bore (56, 56?), a spring-loaded valve member (59, 59?) of a non-return valve is arranged.

Abstract: A piston pump (10) for a hydraulic consumer of an electronically controlled vehicle brake system, carries a stepped piston (50, 50?) and centers a sealing assembly (26, 26?) which is retained in an axial direction Ax by a step (52, 52?) on the stepped piston (50, 50?), on the one hand, and is retained by a spring cage (53, 53?), on the other hand. The stepped piston (50, 50?) includes a plane support (54, 54?) for plane support legs (55a,b,c; 55a,b,c?) of the spring cage (53, 53?) The stepped piston (50, 50?) includes radially inwards, with respect to the support (54, 54?), a stepped bore (56, 56?), with the bore (56, 56?) accommodating centering legs (57a,b,c; 57a,b,c?) of the spring cage (53, 53?). Coaxially as well as inside the stepped bore (56, 56?), a spring-loaded valve member (59, 59?) of a non-return valve is arranged.

Abstract: In a piston pump, in particular, for the pressure fluid conveyance in hydraulic, slip-controlled brake systems, comprising at least one piston, a suction valve and a pressure valve, it will be possible for the suction and pressure valves to be externally checked in that the suction valve and the pressure valve are formed on a structural unit adapted to be separately handled. Preferably, the structural unit comprises a sleeve-type section in which the piston is guided.

Abstract: In an electrohydraulic unit for pressure control in brake systems for automotive vehicles which includes mechanical, hydraulic and/or electric structural elements such as control valves, accumulator pistons, pump components and pump drive parts arranged in accommodating bores of a one-part housing, and with parallel accommodating bores for control valves disposed in pairs side by side in two rows in a housing surface, the control valves which are connected to the slave cylinders of one vehicle axle that have a volume requirement lower than the volume requirement of the slave cylinders of the other vehicle axle, and the accommodating bores of these control valves have a smaller diameter and are arranged offset from the middle of the row in the direction of a lateral housing surface.

Abstract: To minimize the power losses of the pump motor in a hydraulic brake system with brake slip control and traction slip control, a shut-off valve prevents flow in the suction line when the supply pressure of the pump is sufficient for traction slip control. This prevents the aspiration of further pressure fluid volume from the pressure fluid reservoir. The pump does not return any fluid volume into the pressure fluid reservoir by way of a pressure-relief valve so that the motor of the pump is relieved. Preferably, the shut-off valve is designed so that the master cylinder pressure acts in the opening direction and the supply pressure of the pump acts in the closing direction of the shut-off valve, the valve being biassed in the opening direction by a compression spring.

Abstract: A brake pressure regulator comprising a hydraulically actuable slide valve integrated in a receiving bore within the valve accommodating body. The slide valve, in response to the switching position of the electromagnetic valves, controls the pressure fluid volume between a pressure fluid source and a pressure fluid consumer. The pressure regulator includes pressure fluid channels terminating on both front faces of the slide valve which are hydraulically connected through an inlet valve to the pressure fluid consumer. Preferably the slide valve includes a circular groove provided with a control edge and interconnecting the pressure fluid source and the inlet valve through a feed-in channel. The invention employs the principle of preventing leakage flows from occurring by suitably arranging pressure fluid channels and sealing elements and by pointedly guiding the pressure fluid flow.

Abstract: The invention is related to a hydraulic unit for hydraulic control and regulation of apparatuses, in particular for brake pressure control apparatuses in anti-lock control systems or for traction slip control systems for automotive vehicles. In order to effectively reduce both the noise level depending on the switching positions of the solenoid valves and its diffusion, the invention is based on the concept that while the outlet solenoid valve is open to limit the volume of pressure agent being taken in from the pressure agent source and flowing to the pressure agent consumer through a slide valve which is integrated into the valve accommodation body, a control edge being active at the slide valve reduces the pressure agent flow due to the lifting stroke motion which is dependent on the pressure differential.