Robert Boschgmbh

Alliedsignal Inc.

Robert Bosch Technology Corporation

Timothy Jay Albert

Gregory Paul Goodzey

Kenneth S Towers

Kevin Johnson

William John Penninger

Milan Klimes

Robert K Wilson

Richard Becker McClain

Bryan Frances Heinz

John Edmund Mackiewicz

Ryan A Kuhlman

George E Brown

Larry G Lohraff

Gary L Doty

Gamil M Rizk

Wendell D Tackett

Thomas A Grana

James Timpa

Jay A Hendershot

Robin Raumer

A vehicle braking system includes a first wheel cylinder, a second wheel cylinder, a master cylinder including a first master cylinder chamber in fluid communication with the first wheel cylinder via a first circuit and a second master cylinder chamber in fluid communication with the second wheel cylinder via a second circuit, and an electronically controlled pressure generating unit separate from the master cylinder. The vehicle braking system is operable to provide braking in a first configuration in which the electronically controlled pressure generating unit pressurizes fluid, through the master cylinder, in the first circuit, to the first wheel cylinder. In the first configuration, the electronically controlled pressure generating unit pressurizes fluid in the second circuit to the second wheel cylinder, bypassing the master cylinder.

Vehicle braking system and method of operating the same

A brake system () for a vehicle includes a brake unit (A;B) having: a fluid reservoir () for containing a volume of brake fluid therein, an ECU (), and an electronically-controlled plunger device () operable to stroke in response to a control signal from the ECU () to supply fluid pressure to at least one wheel cylinder (RL, RR) for vehicle braking. The plunger device () includes: a rod () coupled to an actuator (M), a primary seal () coupled to the rod () and arranged to seal against an inner wall of a plunger chamber, and a secondary seal () surrounding the rod () to seal an interface where the rod () exits the plunger chamber. A portion of the plunger chamber between the primary and secondary seals () is coupled through a switchable valve () to the fluid reservoir (). A method of operating a brake system () for self-contained brake circuit filling comprises the steps of providing a brake unit (A;B), performing a pressure bleed on a first portion of a brake circuit, supplying pressurized brake fluid to a wheel (RL) coupled to the first portion and supplying brake fluid from a reservoir () to a second portion of the brake circuit by switching a valve () while using a plunger device () under control of an ECU ().

Vehicle brake system for self-contained circuit filling and method of operating

A system for use in a vehicle with a brake pedal and a brake circuit. The system includes a master cylinder assembly configured to pressurize fluid therein in response to movement of the brake pedal, a sensor assembly configured to generate a pedal position signal indicative of position of the brake pedal, an electronic control unit configured to (i) generate a brake request signal in response to generation of the pedal position signal, and (ii) generate a selector control signal, and a selector valve assembly being moved from a first mode to a second mode in response to generation of the selector control signal, the master cylinder assembly is (i) isolated from fluid communication with the brake circuit when the selector valve assembly is positioned in the first mode, and (ii) in fluid communication with the brake circuit when the selector valve assembly is positioned in the second mode.

Brake system with selector valve for selecting between two modes of operation

An in-line brake system with a hydraulic booster includes a master cylinder defining a cylinder bore, a master cylinder piston located within the cylinder bore, a transfer piston located within the cylinder bore rearwardly of the master cylinder piston, a transfer piston actuator with a first seat, a sealing member aligned with the first seat, a sealing member spring operably connected to the sealing member and the transfer piston, an input rod aligned with the first seat, a return spring operably connected to the input rod and the transfer piston actuator, a sleeve actuator located within the cylinder bore rearwardly of the master cylinder, and a sleeve spring configured to bias the sleeve actuator away from the master cylinder piston, wherein the sleeve actuator is configured to bias the transfer piston toward the master cylinder piston in response to an applied boost pressure.

Decoupled inline hydraulic booster

A system for use in a vehicle with a brake pedal and a brake circuit which includes a master cylinder assembly, a sensor assembly configured to generate a pedal position signal indicative of position of the brake pedal, an electronic control unit configured to (i) generate a brake request signal in response to generation of the pedal position signal, and (ii) generate a selector control signal, and a selector valve assembly operable in a first mode and a second mode, the selector valve assembly being moved from the first mode to the second mode in response to generation of the selector control signal, the master cylinder assembly is (i) isolated from fluid communication with the brake circuit when the selector valve assembly is positioned in the first mode, and (ii) in fluid communication with the brake circuit when the selector valve assembly is positioned in the second mode.

Vehicular brake system operable in dual modes

A fast-fill braking system in one embodiment includes a master cylinder, a first chamber within the master cylinder, a second chamber within the master cylinder located forward of the first chamber, a fast-fill piston within the first chamber, a primary piston within the first chamber and movable with respect to the fast-fill piston, and a secondary piston within the second chamber.

Fast-fill tandem master cylinder

An electric brake has a master cylinder () including pistons () for rear and front brake circuits and an electric motor () for actuating the rear brake piston (). A feedback circuit provides a signal indicative of the fluid pressure supplied to the rear brake circuit and is operable in response to driver commanded braking force () to supply fluid pressure to the rear wheel brake circuit. A mechanical coupling () between the second piston and a brake pedal is responsive to driver applied brake pedal force to supply fluid pressure to the front wheel brake circuit. A fluid circuit () utilizes the fluid pressure supplied to the rear wheel brake circuit to augment driver applied brake pedal force thereby supplying power boosted fluid pressure to the front wheel brake circuit.

Electric booster with hydraulic transmission

An electric power booster () where driver command is monitored by a transducer () on an input rod (). This signal is converted to the appropriate voltage/current and operates an electric motor (). The motor output shaft () is connected to a planetary gear reducer () appropriately sized to provide no more than +/&#x2212;1/4 turn of an eccentric cam (). Two master cylinders () power piston rods () ride diametrically opposed on the cam surface (). As the cam rotates the piston rods are forced out pressurizing the respective hydraulic circuits and thereby providing fluid to each brake circuit (). In the event of power failure as well as to augment the output of the motor, the input rod is mechanically linked directly to the cam offset from the center allowing the driver to manually rotate the cam thereby pressurizing the brake circuits.

Eccentric cam brake booster

A control valve of a hydraulic brake booster for use in a brake system. The control valve is characterized by a shuttle member having a stem on a first end and an annular projection on a second end. The stem has an annular surface thereon that is matched with an orifice from an supply chamber such that metered pressurized fluid is uniformly presented to an actuation chamber to effect a brake application while the annular projection is matched with a flange on an actuator piston such that the pressurized fluid present in the actuation chamber is uniformly metered to a reservoir.

Control valve for a hydraulic brake booster

A hydraulic brake booster has an actuator arrangement for a control valve that includes a ball that is located in a first sleeve retained in a stepped bore of a cylindrical member and a pin that is retained in the cylindrical member. The pin has a first end that is located in an actuation chamber and is connected with a first input member and a second end that extends into the stepped bore to engage the ball. The first end on receipt of a first input force initially moves the pin and ball from a position of rest to interrupt fluid communication between the actuation chamber and a reservoir and thereafter moves the sleeve to selectively initiate metered communication of pressurized fluid to the actuation chamber that acts on a first piston to effect a first brake application of a wheel brake. A second sleeve that surrounds the pin has a lip on a first end that engages the cylindrical member to position a second end thereon in an auxiliary actuation chamber within the housing of the brake booster. The second sleeve responds to a second input force derived from pressurized fluid being presented to the auxiliary actuation chamber as a function of a second input by acting on the second end of the second sleeve to move the first end into engagement with the ball and move the ball from a position of rest to interrupt fluid communication between the actuation chamber and the reservoir and thereafter move the first sleeve to communication of pressurized fluid to the actuation chamber that acts on the first piston as a function of the second input to independently effect a second brake application of a wheel brake.

Hydraulic brake booster

A hydraulic brake booster for use in a brake system having a housing with a power piston located in a first bore and a control valve located in a second bore. An input member is connected to the power piston and linked to the control valve by a lever arrangement. The input member is characterized by a cylindrical body with a shaft attached thereto. A bracket with a radial opening is carried by the shaft and urged toward a head on the shaft by a spring. The lever arrangement is characterized by a first lever with a first end pivotally secured in the housing by a first pin and a second end located in the radial opening of the bracket and a second lever pivotally secured at a fulcrum on the first lever by a second pin extending through the first and second levers. A first input force applied to the cylindrical body is transmitted through the spring into the bracket and communicated through the fulcrum point to bring a first end of the second lever into engagement with the control valve and a second end of the second lever into engagement with the power piston. The first input force as applied to the bracket causes the end of the first lever to pivot about the first pin and transmit an actuation force through the fulcrum into the said second pin to move said first end and activate said control valve to meter pressurized fluid into the working chamber to develop a hydraulic force for effecting a brake application. The lever arrangement ratio defined by a first length between the first pin and the second end on the first lever and a second length between the first pin and the second end of the second lever such that axial movement of the cylindrical body and the power piston is defined by this ratio and as a result a hydraulic force produced by the metered pressurized fluid proportional to a manual input force.

A brake booster amplifies driver brake pedal input into an output force and travel for operating a master cylinder. A power unit builds and stores high pressure fluid to provide boost. Inlet and outlet solenoid valves regulate pressurized fluid to the amplifying mechanism. In one embodiment, a single boost chamber provides fluid pressure to operate the master cylinder and to provide a brake pressure indicative opposing force to driver input. One travel sensor monitors the position and movement of an input rod and piston, and a second travel sensor monitors the position and movement of an output piston. An ECU monitors system parameters and controls a motor pump, inlet and outlet valves and peripherals. In another embodiment, the opposing force to the brake pedal input is provided by a separate pressure fluid chamber located within and movable with the output piston. Boost chamber pressure and, optionally, output piston travel are monitored to provide a braking force indication. An ECU monitors system parameters including input travel and boost chamber pressure, and controls the inlet and outlet valves and peripherals.

Electro-hydraulic brake booster

A brake system ( ) having a brake booster ( ) that is responsive to an operator brake input for providing a first input force to a master cylinder ( ) to develop a first brake application and is responsive to a hydraulic input for providing a second input force to a master cylinder ( ) to develop a second brake application. An electronic control unit (ECU) ( ) receives first input signals from sensors ( ) indicative of a speed for each wheel ( &prime;) in a brake system of the vehicle. The ECU ( ) supplies a pump ( ) with an operational input signal when a sensed wheel speed indicates a wheel lock may occur between a wheel and a surface during a brake application and simultaneous activates a decay valve ( ) to release pressurized fluid from actuation of the wheel brake associated with the wheel. When the sensed condition is obviated, the ECU ( ) supplies a signal to close the decay valve ( ) and open a build valve ( ) to provide secondary pressurized fluid from a pump ( ) to the wheel brake to resume and complete the first brake application. The ECU ( ) also receives an input from a pressure sensor ( ) associated to with an accumulator ( ) and when the fluid pressure in the accumulator ( ) is below a preset pressure, the ECU ( ) supplies the pump ( ) with an actuation signal through which pressurized fluid is developed and communicated to maintain the fluid pressure in the accumulator ( ) above the preset pressure. The ECU ( ) supplies valves ( ) associated with the accumulator ( ) with an input signal to deliver pressurized fluid from the accumulator ( ) as the hydraulic input to effect the second brake application.

Hydraulic brake system

A hydraulic brake system wherein a portion of a volume of a first fluid supplied to a steering system by a pump is selectively diverted to an actuator assembly for a master cylinder to develop an force for actuating a master cylinder to pressurize fluid which is supplied to wheel brakes. An electronic control unit (ECU) for the brake system receives a first input signal indicative of the flow of fluid from the pump in the steering system, a second input signal indicative of the input force applied by the operator and a third input signal indicative of the speed of the wheels of the vehicle for developing a pulse modulated operational signal. The electronic control develops an operational signal which is supplied as the pulse modulated operational signal to a magnetic responsive valve. The pulse modulated operational signal creates a variable orifice in the magnetic responsive valve to restrict the flow of the first fluid to the steering gear and increases the fluid pressure of the first fluid. This increase in the fluid pressure of the first fluid is develops an operational force for actuating the master cylinder to effect a brake application. The electronic control unit supplies the pulse modulated operational signal to the magnetic responsive valve until a desired braking of the vehicle is achieved.

Hydraulic braking system

A secondary source of braking for large hydraulically braked vehicles utilizing the available power source (,) provided by typically available anti-skid and traction control braking systems. The anti-skid braking system is used to control the secondary braiding function in a manner optimal to the operating condition of the vehicle. Unique distinctive operating modes are used when the vehicle is either moving (,), or stationary (,). The advantages of the stationary mode are fast time response and high output pressure controlled with a minimum of pump operation and fluid movement. The advantages of the dynamic mode are the ability to modulate brake pressure in response to the driver's command.

Growing community of inventors

Niles, MI, United States of America

Timothy Jay Albert