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US 4,914,917 AGranted
Brake actuating device for automotive vehicles
AssigneeAlfred Teves GmbH
InventorJuergen Schonlau
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AssigneeAlfred Teves GmbH
InventorJuergen Schonlau
Estimating the term…
A brake actuating device for automotive vehicles comprises a hydraulic brake force booster and a hydraulic tandem master cylinder to which pressure is applied by the brake force booster and which is in communication with the hydraulic wheel brake circuits. The hydraulic piston of the brake force booster applies pressure to the primary master piston of the said hydraulic tandem master cylinder. Pressure is applied to the hydraulic piston of the hydraulic brake force booster from a hydraulic pressure source through a normally closed opening valve which, through a function electronic unit receiving by way of a control input in the form of a guide quantity, an input signal representative of the pedal travel is alternately opened and closed. Accordingly the hydraulic brake pressure build-up is effected in accordance with a predetermined function stored in the function electronic unit between pedal travel and brake pressure with no lost motion of the brake pedal.
A brake actuating device for automotive vehicles comprising a hydraulic brake force booster and a hydraulic master cylinder to which pressure is applied by the brake force booster and which is in communication with the hydraulic wheel brake circuits, with a hydraulic piston of the brake force booster applying pressure to a primary master piston of said hydraulic master cylinder, wherein pressure is applied to the hydraulic piston of the hydraulic brake force booster by a hydraulic pressure source through a normally closed opening valve which, through a function electronic unit receiving, by way of a control input forming a guide quantity, an input control signal representative of brake pedal travel and derived from a travel sensor is alternately opened and closed so that the hydraulic brake pressure build-up is effected in accordance with a predetermined function stored in the function electronic unit between pedal travel and brake pressure with no lost motion of the brake pedal, and wherein the function electronic unit includes another regulation input through which the actual pressure factually prevailing in the pressure chamber of the hydraulic brake force booster is reported by a pressure sensor connected to the pressure chamber to the function electronic unit.
The brake actuating device according to c1aim 6, wherein the pressure source supplies an operating pressure of between 4 and 8 bar.
The brake actuating device according to c1aim 1, wherein an energy accumulator is provided between the pressure source and the brake force booster.
The brake actuating device for automotive vehicles comprising a hydraulic brake force booster and a hydraulic master cylinder to which pressure is applied by the brake force booster and which is in communication with the hydraulic wheel brake circuits, with a hydraulic piston of the brake force booster applying pressure to a primary master piston of said hydraulic master cylinder, wherein pressure is applied to the hydraulic piston of the hydraulic brake force booster by a hydraulic pressure source through a normally closed opening valve which, through a function electronic unit receiving, by way of a control input forming a guide quantity, an input control signal representative of brake pedal travel and derived from a travel sensor is alternately opened and closed so that the hydraulic brake pressure build-up is effected in accordance with a predetermined function stored in the function electronic unit between pedal travel and brake pressure with no lost motion of the brake pedal, and wherein the pressure of the pressure source is connected to the hydraulic pressure chamber through the opening valve to which pressure is applied by the function electronic unit and through a control valve provided between the actuating rod to which pressure is applied by the brake pedal, and wherein the hydraulic piston and the control valve are arranged to solely establish the connection between the pressure source and the pressure chamber if the opening valve remains closed due to a malfunction upon a brake pedal actuation.
The brake actuating device according to claim lB, wherein the central port extends to a cylindrical intermediate member connected to which is a radial bore leading to an annular chamber between the intermediate member and a cylindrical element surrounding the latter, and wherein a radial connection is provided in the cylindrical member which, through a hydraulic conduit, is in communication with the return tank.
Dependencies are inferred from the claim text.