Abstract: An anti-lock brake controller that is operable, upon detecting a potential wheel lock-up situation during a vehicle braking cycle, to cycle apply and dump valves associated with vehicle rear wheels continuously between apply and dump modes to determine an estimated maximum friction wheel slip. The controller then is further operable to utilize the estimated maximum friction wheel slip to determine reference velocities that are used to continuously control apply and dump valves associated with the vehicle front wheels to optimize vehicle braking.

Abstract: An apparatus and method for determining the presence of excessive yaw rate in a vehicle by calculating an instability index that is a function of the vehicle yaw rate and generating an excessive yaw rate signal when the instability index exceeds a yaw rate threshold.

Abstract: An Active Roll Control System for a motor vehicle that utilizes small valves to control large flows. Flow is supplied by a hydraulic pump which is powered in some fashion by the motor vehicle. Flow is directed to the actuators by a three-position-four-way valve that is controlled by two pairs of small ABS style solenoid valves. This allows for a minimum of power to be supplied by the vehicle to operate the system. Also, this valve arrangement allows a desirable failure mode whereby hydraulic fluid is locked into the hydraulic actuators, there by locking in the anti-roll bar in case of a system failure.

Abstract: A system is disclosed for controlling the roll of a motor vehicle. The system comprises a selective lock connected between an unsprung portion of the vehicle and a sprung portion of the vehicle.

Abstract: An electrohydraulic brake system where brake pressure is controlled by the combined action of an apply valve and a dump valve by the implementation of a method of controlling the voltage applied to the apply and dump valve. The EHB pressure control system receives a desired wheel pressure command and, with a caliper pressure feedback signal, implements an algorithm to compute one voltage command for the apply valve and another for the dump valve, corresponding to a requested flow from the hydraulics. The voltage command drives current control electronics. The electronics in turn power the solenoids of the proportional apply and dump poppet valves to control flow in or out of the brakes and modulate wheel pressure as required. Use of the algorithm to control the electromagnetic poppet valves achieves the commanded pressure at a vehicle's brakes reliably and with good control in all states of flow through the valve.

Abstract: A valve includes a valve body, a flux tube, and a winding. The body defines first and second passageways, and a circular opening is defined in the second passageway providing fluid communication between the passageways. The flux tube has a closed end, an open end, and a hollow armature receiving section. The open end is in fluid communication with the first passageway. A spherical armature is disposed in the armature receiving section for reciprocating movement between a closed position sealing against the circular opening to prevent communication between the passageways and an open position spaced apart from the opening permitting communication between the passageways. The winding is disposed about the flux tube for electromagnetically positioning the armature. The flux tube forms a fluid tight pressure boundary between the winding and the passageways. A spring urges the armature toward one of the open position and the closed position.

Abstract: A valve seat assembly for a control valve of a vehicle brake system includes a valve seat body. A valve passageway extends through a portion of the valve seat body. A groove is formed circumferentially in an outer surface of the valve seat body. The groove defines a groove surface substantially parallel to an axis of the valve body. A bore extends between the groove surface and the valve passageway to provide fluid communication between the groove surface and the valve passageway. A substantially resilient seal is disposed in the groove of the valve seat body.

Abstract: This invention relates to a brake caliper adapted for use in a vehicle disc brake assembly and method and apparatus for producing the same. The method for producing the brake caliper comprises the steps of: (a) providing a mold member having at least two mold sections; (b) providing a core member having at least a first male extension which is adapted to form an integrally cast locating recess in the brake caliper which is used as a locating surface for subsequent machining of the brake caliper; (c) disposing the core member in the mold member in a predetermined position; (d) supplying a suitable material to the mold member so as to form a brake caliper within the mold; (e) removing the brake caliper from the mold, wherein the brake caliper includes an integrally cast locating recess formed therein by the first male extension of the core member; and (f) machining the brake caliper using at least the integrally cast locating recess formed therein as a locating surface.

Abstract: A method is provided for detecting a rollover event of a vehicle. A lateral kinetic energy of the vehicle is determined in response to vehicle longitudinal velocity and vehicle side slip angle. A lateral acceleration of the vehicle is measured. A rollover potentiality index is determined in response to the lateral kinetic energy and the lateral acceleration. A rollover index is determined by weighting the rollover potentiality index by a factor of the lateral acceleration. A comparison is made to determine if the rollover index is above a predetermined threshold.

Abstract: An apparatus and control method for a motor vehicle having steerable front and rear wheels and an associated wheel brake for each wheel. The apparatus and control method includes a sensor for generating a vehicle dynamic state signal based upon a sensed vehicle dynamic state of the vehicle. A vehicle stability control system is provided to control the selective braking of the wheel brakes of the vehicle based, at least in part, upon the vehicle dynamic state signal. A rear wheel steering system for controlling steering of the rear wheels based, at least in part, upon the vehicle dynamic state signal is also provided.

Abstract: In a method of controlling an actuator of a microvalve, a controller is provided for supplying a voltage to the actuator. The controller provides an initial voltage to the actuator which is effective to actuate the microvalve. Then, the controller provides a pulsed voltage to the actuator which is effective to continue the actuation of the microvalve.

Abstract: A self-cleaning orifice includes a housing having a bore defined therein. The bore includes a first diameter inlet portion and a second diameter outlet portion, with a seating surface defined between the inlet and outlet portions. A movable body having a seating surface with a groove defined thereon is disposed within the outlet portion of the bore. The body is movable relative to the housing to a first position in which the seating surface of the body is seated against the seating surface of the housing and provides a restricted flow between the inlet portion and the outlet portion of the bore The body is also movable relative to the housing to a second position in which the seating surface of the body is spaced apart from the seating surface of the housing creating an unrestricted fluid flow path between the inlet portion and the outlet portion of the bore.

Abstract: A brake module provides a first circuit, a second circuit, and a third circuit of pressurized brake fluid. A first set and second set of brake actuators are operated by the application of pressurized brake fluid. A first and second fluid separator unit are integrated between the first and second circuit, and the first and third circuit, respectively, for substantially preventing any intermixing of pressurized brake fluid between the first, second, and third circuits. The first and second fluid separator units include a moveable pressure boundary which enables the second circuit and third circuit of pressurized brake fluid to selectively act upon the first set and second set of brake actuators in response to the first circuit of pressurized brake fluid acting upon the first and second fluid separator units. At least one proportional valve selectively controls the pressurized brake fluid of the first circuit for acting on the first and the second fluid separator units.

Abstract: A composite vehicle wheel hub includes an inner wheel hub portion formed from a first material and an outer wheel hub portion formed from a second material and joined to the inner wheel hub portion. A method for producing the composite vehicle wheel hub of this invention includes the steps of: (a) providing one of an inner wheel hub portion and an outer wheel hub portion formed from a first material; (b) placing the one of the inner wheel hub portion and the outer wheel hub portion in a mold; (c) casting the other one of the inner wheel hub portion and the outer wheel hub portion formed from a second material in situ within the mold to thereby produce the composite vehicle wheel hub; and (d) removing the composite vehicle wheel hub from the mold.

Abstract: A pump assembly with a combination reciprocating high-pressure seal and fluid inlet check valve for use within brake systems. The pump assembly comprises a housing having a bore formed therethrough and a piston disposed within the bore for reciprocal movement therein. An annular seal is disposed around the piston for reciprocal movement thereon. The annular seal cooperates with the piston and/or the housing to form at least one longitudinally extending passageway. The passageway, the piston, the annular seal, and the housing cooperating to form a check valve assembly. The annular seal is moveable to a first position relative to the piston in which the check valve assembly is in a flow-through position to fill a pump chamber with fluid from an inlet chamber during a fluid inlet stroke. The annular seal is moveable to a second position relative to the piston in which the check valve assembly is closed.

Abstract: This invention relates to an improved park brake cable end assembly for a drum-in-hat disc brake assembly having a disc service brake and a drum-in-hat parking and emergency brake. The drum-in-hat disc brake assembly includes a backing plate adapted to support a drum brake shoe assembly of the drum-in-hat parking and emergency brake; a caliper bracket adapted support a disc brake caliper assembly of the disc service brake; and a drum-in-hat adapter adapted support a disc brake caliper assembly of the disc service brake. According to a feature of the present invention, the drum-in-hat parking and emergency brake includes a park brake cable end assembly including a lever pivotally supported on a link having an end having a configuration which is adapted to accommodate either a parking brake cable having a S-shaped cable end or a clevis shaped cable end.

Abstract: A hydraulic braking system including first and second braking circuits. The first and second braking circuits each include a wheel brake, a pressurized fluid source, and a hydraulic conduit connecting the wheel brake to the fluid source. Each of the hydraulic conduits includes a control valve that operates to selectively prevent fluid flow from the pressurized fluid source to the wheel brake. A connecting conduit connects the first and second braking circuits. A floating piston is disposed within the connecting conduit and is adapted to be displaced by the pressurized fluid provided by the pressurized fluid source in the first braking circuit when the control valve of the first braking circuit is closed. The displacement of the piston generates an additional volume of pressurized fluid in the hydraulic conduit of the second braking circuit that effectively augments the pressurized fluid provided by the second pressurized fluid source.

Abstract: This invention relates to a pad spring for use in a disc brake assembly. According to one embodiment of the present invention, the disc brake assembly comprises an anchor bracket adapted to be secured to a vehicle component; a brake caliper adapted to be secured to the anchor bracket; an inboard friction pad and an outboard friction pad carried by the disc brake assembly and adapted to be disposed on opposite axial sides of an associated brake rotor; actuation means for selectively moving the inboard and outboard friction pads into frictional engagement with the rotor; and a pad spring carried by at least one end of one of the friction pads for moving the friction pads from engagement with the rotor when the actuation means is released; wherein the pad spring includes a first portion for applying a first retraction force and a second portion for applying a second retraction force which is different from the first retraction force.

Abstract: A vehicle brake system includes a master cylinder having a housing defining a bore therein. A boost piston and a primary piston are slidably disposed in the bore. The master cylinder has a boost chamber defined at least in part by the boost piston and the housing. The system further includes a source of pressurized fluid and a boost valve operable to supply fluid from the source of pressurized fluid to the boost chamber for advancing the boost piston and the primary piston in the master cylinder. According to one aspect of the invention, the boost valve is housed in the boost piston. According to another aspect of the invention, the brake system includes a switchable travel rate feature. According to yet another aspect of the invention, the master cylinder includes a jump in feature. Additional features of the invention are also described herein.

Abstract: A brake booster assembly is temporarily mounted on a vehicle dash panel by use of a clip. The brake booster assembly includes a housing and at least one mounting bolt extending outwardly from an outer wall of the housing. The mounting bolt extends through an aperture of the vehicle panel to mount the brake booster to the vehicle panel. The clip is fastened to the mounting bolt. The clip has a securing structure for engaging with a wall of the vehicle panel to at least temporarily mount the brake booster to the vehicle panel.