Abstract: The present invention discloses a braking apparatus for a vehicle having a brake pedal. The braking apparatus includes a master cylinder having a reservoir for retaining a brake fluid. At least one hydraulically actuated brake is in fluid communication with the master cylinder and a control unit is in electrical communication with the hydraulically actuated brake. A replenishment system is in fluid communication with the master cylinder and in electrical communication with the control unit for feeding the brake fluid into the replenishment system during a first condition and feeding the brake fluid from the replenishment system into the hydraulically actuated brake during a second condition after initial depression of the brake pedal to provide consistent pedal feel and braking pressure.

Abstract: A brake-by-wire braking system including a braking unit, an electro-hydraulic actuator in fluid communication with the braking unit by way of a first fluid path, a master cylinder in fluid communication with the braking unit by way of a second fluid path, a normally open solenoid valve operatively associated with the second fluid path, and a control unit adapted to actuate the normally open solenoid valve, wherein actuation of the normally open solenoid valve generally fluidly isolates the master cylinder from the braking unit.

Abstract: The present invention discloses a braking apparatus for a vehicle having a brake pedal. The braking apparatus includes a master cylinder having a reservoir for retaining a brake fluid. At least one hydraulically actuated brake is in fluid communication with the master cylinder and a control unit is in electrical communication with the hydraulically actuated brake. A replenishment system is in fluid communication with the master cylinder and in electrical communication with the control unit for feeding the brake fluid into the replenishment system during a first condition and feeding the brake fluid from the replenishment system into the hydraulically actuated brake during a second condition after initial depression of the brake pedal to provide consistent pedal feel and braking pressure.

Abstract: A brake-by-wire braking system including a braking unit, an electro-hydraulic actuator in fluid communication with the braking unit by way of a first fluid path, a master cylinder in fluid communication with the braking unit by way of a second fluid path, a normally open solenoid valve operatively associated with the second fluid path, and a control unit adapted to actuate the normally open solenoid valve, wherein actuation of the normally open solenoid valve generally fluidly isolates the master cylinder from the braking unit.

Abstract: A disc brake caliper assembly has a housing with a bore. A piston in the bore is movable between applied, retracted and knock-back positions. The piston is activatable by hydraulic pressure to move from the retracted position to the applied position; and a retracting seal is effective in the absence of the hydraulic pressure to move the piston from the applied position to the retracted position. A linkage adjacent the piston carries a stop; and an actuator is responsive to an end of brake activation signal to cause the linkage to engage the stop with the piston when the piston is retracted from its applied position to its retracted position so as to prevent the piston from moving from the retracted position to the knock-back position. The actuator is preferably a comparatively weak electric motor that stalls as the stop engages the piston; and the stall is sensed to end motor activation. The end of brake activation signal is preferably provided by a brake position or pressure sensor.

Abstract: A brake pedal assembly for a vehicle equipped with an electronic or “brake-by-wire” braking system includes a brake pedal feel emulator which mimics or emulates the pedal feel of a conventional hydraulic braking system. The brake pedal feel emulator includes a single cantilever spring which reacts against a shaped surface and is mounted such that the free end thereof applies a force to the brake pedal which varies as the point at which the spring diverges from the shaped surface changes in response to movement of the brake pedal. The free length of the spring is therefor varied as the pedal is depressed as a function of the shape of the shaped surface, so the force applied to the pedal may be designed to vary to emulate the feel of a conventional braking system.

Abstract: A disc brake caliper assembly is provided that includes a housing having a bore. A piston is arranged within the bore and is movable between normal retracted and knock-back positions. A linkage is adjacent to the piston and is movable between first and second positions with a clearance between the piston and the linkage in the first position. The clearance undesirably permits the piston to move to the knock-back position during severe operating conditions. An actuator, which also may be used as part an electric parking brake, moves the linkage from the first position to the second position to eliminate the clearance when the linkage is moved from the first position to the second position where the linkage abuts the piston. The linkage is connected to the caliper housing by a support. The linkage prevents the piston from moving from the normal retracted position to the knock-back position.

Abstract: A parking brake assembly for an automotive drum brake is provided. The parking brake assembly replaces a conventional mechanical strut with an electronic strut actuator subassembly that provides for parking brake engagement and disengagement, sensing of brake lining wear and adjustment of brake shoe-to-drum clearance.

Abstract: A parking brake assembly for an automotive drum brake is provided. The parking brake assembly replaces a conventional mechanical strut with an electronic strut actuator subassembly that provides for parking brake engagement and disengagement, sensing of brake lining wear and adjustment of brake shoe-to-drum clearance.

Abstract: An emulator affixed to a brake arm connected to a brake pedal of an electric brake system is capable of emulating a hydraulic brake. The emulator includes a housing defining a fluid chamber containing a magneto-rheological (MR) fluid. A piston is slideably disposed within the piston chamber and a spring biases the piston to resist depression of the brake pedal. A magnetic source generates a magnetic field upon the MR fluid thereby increasing the sheer resistance of the MR fluid further resisting depression of the brake pedal emulating a hydraulic brake system. The amount of resistance can be varied according to the strength of the magnetic field exerted on the MR fluid.

Abstract: A disc brake caliper with an integral parking brake includes a caliper housing defining a cavity therein and a piston axially translatable within the cavity and having an internal bearing surface. At least one brake pad is affixed to either the piston or the caliper housing. A parking brake mechanism is mounted within the cavity and is interposed between a portion of the housing and the piston. The parking brake mechanism includes a thrust pin substantially axially aligned with the piston and rotatable within the housing. A first radial clutch is engageable with the thrust pin, and a second axial clutch is operable upon the piston. Rotation of the thrust pin in a first direction causes engagement of the first radial clutch and of the second axial clutch causing axial displacement of the piston. Rotation of the thrust pin in an opposite direction causes disengagement of the first and said second clutches.

Abstract: A disc brake caliper with an integral parking brake includes a caliper housing defining a cavity therein and a piston axially translatable within the cavity and having an internal bearing surface. At least one brake pad is affixed to either the piston or the caliper housing. A parking brake mechanism is mounted within the cavity and is interposed between a portion of the housing and the piston. The parking brake mechanism includes a thrust pin substantially axially aligned with the piston and rotatable within the housing. A first radial clutch is engageable with the thrust pin, and a second axial clutch is operable upon the piston. Rotation of the thrust pin in a first direction causes engagement of the first radial clutch and of the second axial clutch causing axial displacement of the piston. Rotation of the thrust pin in an opposite direction causes disengagement of the first and said second clutches.

Abstract: A drum brake assembly for a vehicle is provided. A backing plate supports opposing brake shoes with a drum disposed there about. Each of the brake shoes has a portion in spaced relation from one another. A wheel cylinder is supported by the backing plate and is arranged between the portions of the brake shoes for forcing the portions away from one another to engage the brake shoes with the drum in a brake position. A strut interconnects the brake shoes proximate to the portions. A lever has a first end, which extends to a second end, supported from one of the portions by a pivotal connection. The lever is rotatable about the pivotal connection between a normal operating position in which the strut is spaced from the lever and a parking brake position in which the lever engages the strut to maintain the portions in the brake position. An electric parking brake actuator is supported by the backing plate and includes a linkage that coacts with the second end of the parking brake lever.

Abstract: A disc brake caliper assembly has a housing with a bore. A piston in the bore is movable between applied, retracted and knock-back positions. The piston is activatable by hydraulic pressure to move from the retracted position to the applied position; and a retracting seal is effective in the absence of the hydraulic pressure to move the piston from the applied position to the retracted position. A linkage adjacent the piston carries a stop; and an actuator is responsive to an end of brake activation signal to cause the linkage to engage the stop with the piston when the piston is retracted from its applied position to its retracted position so as to prevent the piston from moving from the retracted position to the knock-back position. The actuator is preferably a comparatively weak electric motor that stalls as the stop engages the piston; and the stall is sensed to end motor activation. The end of brake activation signal is preferably provided by a brake position or pressure sensor.

Abstract: A brake by wire system provides the capability of both travel and force sensors on a brake apply input member such as a brake pedal and also provides redundancy in sensors by providing the signal from a sensor responsive to travel or position of the brake pedal to a first controller and the signal from a sensor responsive to force applied to the brake pedal to a second controller. The first and second controllers are connected by a bi-directional communication link whereby each controller may communicate its received one of the sensor signals to the other controller. In at least one of the controllers, linearized versions of the signals are combined for the generation of first and second brake apply command signals for communication to brake apply units. If either controller does not receive one of the sensor signals from the other, it nevertheless generates its brake apply command signal on the basis of the sensor signal provided directly to it from the sensor.

Abstract: A brake by wire system provides the capability of both travel and force sensors on a brake apply input member such as a brake pedal and also provides redundancy in sensors by providing the signal from a sensor responsive to travel or position of the brake pedal to a first controller and the signal from a sensor responsive to force applied to the brake pedal to a second controller. The first and second controllers are connected by a bi-directional communication link whereby each controller may communicate its received one of the sensor signals to the other controller. In at least one of the controllers, linearized versions of the signals are combined for the generation of first and second brake apply command signals for communication to brake apply units. If either controller does not receive one of the sensor signals from the other, it nevertheless generates its brake apply command signal on the basis of the sensor signal provided directly to it from the sensor.

Abstract: An electro-hydraulic actuator for a motor vehicle brake-by-wire brake system including a housing, a piston bore in the housing, a T-shaped piston in the piston bore, and an electric motor connected to the piston through a speed reducer. The T-shaped piston includes a disc-shaped head in the piston bore and a tubular stem perpendicular slidable in and out of the piston bore through a sealed guide in the bottom of the piston bore. The top side of the piston head opposite the stem constitutes a large effective area of the piston for rapidly expelling a relatively large volume of fluid from the piston bore in a low pressure interval of operation the actuator. When the fluid pressure in the piston bore exceeds a transition pressure, a transition valve opens a bypass passage to the piston bore behind the piston head so that the same fluid pressure reacts against the bottom side of the piston head around the stem.

Abstract: A brake pedal for a motor vehicle brake-by-wire brake system including a pedal lever pivotally supported on a body of the motor vehicle, a foot pad on the pedal lever, and a compliant member having a plurality of parallel beams defining cantilever springs. A pedal force on the foot pad effects pedal travel of the pedal lever from a release position toward a brake full apply position. The parallel beams defining cantilever springs are arrayed in series between the pedal lever and the motor vehicle body and engage is series so that the effective stiffness of the compliant member increases during pedal travel. The stiffness of each of the parallel beams and the magnitudes of a plurality of clearance spans therebetween are “tuned” to yield a pedal force which initially increases slowly relative to pedal travel and then increases exponentially relative to pedal travel thereby emulating the relationship between pedal force and pedal travel of a brake pedal in a traditional motor vehicle brake system.

Abstract: A brake pedal for a motor vehicle brake-by-wire brake system including a pedal lever resiliently flexible in beam bending, a foot pad on the pedal lever, and a mounting for the pedal lever on a body of the motor vehicle which constitutes the pedal lever a variable stiffness cantilever spring. The mounting for the pedal lever includes a socket for an inboard end of the pedal lever, a stationary reaction surface on the body of the motor vehicle, and a pedal lever reaction surface on the pedal lever which faces and diverges from the stationary reaction surface in a release position of the pedal lever. The stationary reaction surface and the pedal lever reaction surface become progressively engaged concurrent with resilient flexure of the pedal lever in cantilever spring bending to vary the stiffness of the cantilever spring.

Abstract: A brake system includes a pedal feel emulator and a master cylinder with a damping mechanism having a damping piston. When the emulator piston is moved from the at-rest position, fluid is displaced from the emulator through a compensation port and through a flow restrictive orifice in the damping piston to the reservoir. Flow rate of the fluid is dependent on the apply rate of the brake pedal. When the brake pedal is applied relatively slowly, sufficient flow volume will occur through the flow restrictive orifice and the damping piston will remain unmoved. As apply rates increase, a sufficient pressure differential will eventually be established across the damping piston to cause it to move. Damping piston movement compensates for rapid fluid displacement out of the variable chamber and enables a desirable pedal feel characteristic where pedal force increases relatively slowly as pedal velocity increases relatively rapidly.