Abstract: A hydraulic braking system for an automotive vehicle is provided with a power source for generating a hydraulic power pressure, a master cylinder, a hydraulic booster for introducing the hydraulic power pressure and actuating the master cylinder in response to operation of a brake operating member, a wheel brake cylinder for braking a road wheel, a changeover valve, and anti-skid control device for actuating the changeover valve into a position where the wheel brake cylinder is communicated with the booster and regulating the hydraulic pressure in the wheel brake cylinder on the basis of the hydraulic power pressure in the booster when the road wheel is in a slip condition.

Abstract: A tandem master brake cylinder has first and second pistons, each piston associated with a fluid chamber and a pressure chamber. The pistons are displaced in response to actuation of a brake pedal. A hydraulic booster is coupled to a power source and is operable to enhance the piston movement and for conducting pressurized fluid to a second of the fluid chambers associated with a second piston to displace that piston in a manner reducing the volume of the pressure chamber associated with the first piston. In the event that a negative pressure is communicated with the second fluid chamber, e.g. by a loss of pressurized fluid from the power source, brake fluid is supplied through a one-way check valve to the second fluid chamber to prevent the negative pressure from reversing the motion of the second piston.

Abstract: A hydraulic braking system for an automotive vehicle having a power source for generating a hydraulic power pressure, a reservoir, a master cylinder having a master piston, a hydraulic booster for actuating the master cylinder in response to depression of a brake pedal and a plurality of wheel brake cylinders connected to the master cylinder for braking respective road wheels. The hydraulic booster is provided with a power piston which is larger in diameter than the master piston. The power piston transmits a force to the master piston through a closed chamber which is defined between the power piston and the master piston, when the hydraulic power pressure is supplied to the hydraulic booster in response to depression of the brake pedal. The closed chamber is filled with a brake fluid which is supplied from the reservoir. Thus, a small stroke of the power piston will suffice for operating the master piston at a predetermined stroke, so that the stroke of the brake pedal is reduced.

Abstract: A hydraulic braking system includes a tandem master cylinder having a bore with an opening and a closed wall at opposite ends thereof which formed in a housing, a first piston slidably fitted in the bore so as to define a first pressure chamber and a first fluid chamber therein and operatively connected to a brake pedal, a second piston slidably fitted in the bore so as to define a second fluid chamber adjacent to the first pressure chamber and a second pressure chamber and operatively connected to the first piston. A normally open valve communicates with each piston so as to close passages formed in the each pistons and communication between each fluid chambers and each pressure chambers, respectively, when each piston is moved in response to the depression of the brake pedal. A power source generates a hydraulic power pressure.

Abstract: A hydraulic braking system for an automotive vehicle having a power source for generating a hydraulic power pressure, a reservoir, a master cylinder, a hydraulic booster for actuating the master cylinder in response to depression of a brake pedal and a plurality of wheel brake cylinders for braking respective road wheels, which are divided into a first group of wheel brake cylinders communicating with the master cylinder and a second group of wheel brake cylinders communicating with the hydraulic booster. An auxiliary cylinder is disposed between the hydraulic booster and the second group of wheel brake cylinders. The auxiliary cylinder includes a cylinder body having a cylinder bore defined therein and a piston axially slidably disposed within the cylinder bore. The piston forms within the cylinder bore a first chamber and a second chamber, and blocks a fluid communication therebetween.

Abstract: A hydraulic braking system is provided in which the speed of increase of the hydraulic pressure to the wheel cylinders is controlled so that appropriate braking force is ensured while at the same type preventing the road wheels from being positioned in a lock-up condition. In order to provide for such an operation, the locking condition of the road wheels may be detected during braking operation and the anti-lock control system operated so that changeover valves are positioned by a control system so that output pressure of a hydraulic booster is applied to the anti-lock control valves and to the flow control valves so as to appropriately changeover between one of two operating positions in response to the locking condition of the road wheel. In order to provide for such fluid communication of the braking system, a multi-stage orifice arrangement is provided in connection with the anti-lock control valves and the flow control valves.

Abstract: A hydraulic braking system capable of reducing the brake pedal stroke is provided by adding to the basic hydraulic braking system. The adding system is able to selectively execute the reduction of brake pedal stroke and, at the same time, capable of selectively adding anti-lock function and anti-slip function by including the changeover valves or opening and closing valves to the system. An auxiliary hydraulic pressure generator having a power hydraulic pressure source and regulator is interposed in the hydraulic conduit of at least one circuit, and an outlet port of the regulator is communicated to the wheel cylinders for connecting to the hydraulic conduit of the circuit.

Abstract: A hydraulic braking system for an automotive vehicle having a power source for generating a hydraulic power pressure, a reservoir, a master cylinder, a hydraulic booster for actuating the master cylinder in response to depression of a brake pedal and a plurality of wheel brake cylinders for braking respective road wheels, which are divided into a first group of wheel brake cylinders communicating with the master cylinder and a second group of wheel brake cylinders communicating with the hydraulic booster. An auxiliary cylinder is disposed between the master cylinder and the first group of wheel brake cylinders to which a hydraulic braking pressure from the master cylinder is directly applied in its inoperative condition, and it increases the hydraulic braking pressure in response to depression of the brake pedal in its operative condition which is made when the hydraulic power pressure, for example, is less than the hydraulic braking pressure by a predetermined difference.

Abstract: A hydraulic braking system for controlling the hydraulic pressure of the brake actuator and wheel cylinders includes a dynamic hydraulic pressure control system which transmits boosted hydraulic pressure in response to movement of a brake pedal. A master cylinder receives brake fluid pressure from a reservoir and transmits the fluid pressure from a pressure chamber in the master cylinder to a changeover valve. The changeover valve changes over the connection between wheel cylinders of the vehicle and the dynamic hydraulic pressure control system when the powered pressure which is transmitted from the dynamic hydraulic pressure control system is less than a predetermined pressure. A valve member of the changeover valve is movable between a first and second position so as to transmit the powered hydraulic fluid from the boost pressure chamber to the wheel cylinders of the rear wheels in a first position and block the transmission of the fluid in the second position.

Abstract: The hydraulic brake system for a motor vehicle provides a brake fluid level detector which provides a signal to a control apparatus whereby the motor driven pump for providing braking pressure will be deactivated when the brake fluid level falls below a predetermined value. The system is also provided with pressure detector which detects the output fluid pressure and provides a signal to a control apparatus for stopping the anti-locking control apparatus of the brake system if the pressure falls below a predetermined value.

Abstract: A hydraulic brake booster is provided which actuates a master cylinder by a hydraulic power pressure supplied from a power source in response to an input rod connected to a brake pedal. The arrangement includes a housing connected to the master cylinder, a power piston slidably disposed in a boost chamber which defined in the housing and transmitting a boost force which is generated in response to the input rod. A hydraulic pressure control valve is provided which has a valve body moved between a power position communicated with the power source and an initial position communicated with a reservoir in the boost chamber on an axis extending substantially in parallel with a sliding axis of the power piston. A control lever engages with the valve body of the hydraulic pressure control valve at its one end and engages with the power piston at its other end.

Abstract: A pair of spaced apart large-diameter and small-diameter lands between which a fluid chamber is defined are formed on a second piston in a tandem cylinder to which an anti-skid device is added. Booster pressure is applied to the fluid chamber to act on the large-diameter land in a manner fluidly locking the second piston against movement despite a reduction in pressure in the first and second pressure chambers during operation of the anti-skid device. As a result, the movement of the brake pedal in the normal direction of depression is prevented when the anti-skid devices operates.

Abstract: A hydraulic braking system for an automotive vehicle having a power source for generating a hydraulic power pressure, a reservoir, a master cylinder, a regulator and a plurality of wheel brake cylinders for braking respective road wheels, which are divided into a first group of wheel brake cylinders communicated with the master cylinder and a second group of wheel brake cylinders communicated with the regulator. The regulator has a housing defining therein a regulator chamber for introducing the hydraulic power pressure thereinto from the power source and regulating the hydraulic power pressure into a regulated hydraulic pressure in response to the hydraulic braking pressure generated in the master cylinder, and which is positioned in substantially coaxial relationship with the master cylinder and responsive mechanically to depression of a brake pedal.

Abstract: A hydraulic braking system for a vehicle includes a hydraulic power pressure source which produces a hydraulic power pressure and a hydraulic braking pressure generator which generates a hydraulic pressure in response to the operation of a brake pedal. A regulator valve is provided for regulating, in dependence upon the operation of the pressure generator, the pressure which is supplied from the pressure source and for supplying a regulated hydraulic pressure to an output hydraulic pressure passage. A control valve controls the communication between the generator and a plurality of brake cylinders as well as between the regulator valve and the brake cylinders and between a reservoir and the brake cylinders. Also, a changeover valve is provided which, in a first position, blocks communication between the hydraulic pressure source and the output pressure passage of the regulator valve, and which, in a second position, introduces pressure supplied from the pressure source to the output pressure passage.

Abstract: A hydraulic braking system for an automotive vehicle having a hydraulic braking pressure generator arranged to control the communication of a pressure chamber defined therein with a power source and a reservoir in response to depression of a brake pedal. The power chamber is normally communicated with the reservoir through a drain passage when the brake pedal is not depressed. Between the pressure generator and wheel brake cylinders disposed is valve means for controlling the communication of the wheel brake cylinders with the pressure generator and the reservoir. A changeover valve is arranged to normally communicate the power chamber with the reservoir and communicate the power chamber with the power source through the drain passage blocking its communication with the reservoir in a slip condition of driven wheels. In accelerating operation the changeover valve and the valve means are operated depending on the slip condition of the driven wheels to brake the same effectively preventing the slip.

Abstract: A hydraulic brake system includes a master cylinder for generating a brake fluid pressure in response to a brake pedal, a power fluid source for generating a power fluid pressure by increasing a brake fluid to a predetermined pressure. A dynamic fluid pressure control apparatus supplies the brake fluid pressure to regulate the power fluid pressure from the power fluid pressure source in response to the brake pedal. A plurality of wheel cylinders of each wheel for the vehicle are fluidically communicated with a dynamic fluid pressure control apparatus and the master cylinder via a fluid passage separated into plural control systems.

Abstract: A servomotor device which includes a power piston and a diaphragm having an inner bead and which is disposed within a housing so as to divide the same into a constant pressure chamber and a variable pressure chamber, the power piston including a hub having a first shoulder faced toward the variable chamber and a second shoulder faced toward the constant pressure chamber, a pressure plate which includes the power piston engaged with the hub and having an inner sleeve portion engageable with the first shoulder so as to prevent movement of the pressure plate toward the constant pressure chamber with respect to hub, a detent portion unitarily formed on the pressure plate and engageable with the second shoulder so as to prevent movement of pressure plate toward the variable pressure chamber with respect to the hub, and a groove formed in the hub for hermetically retaining the inner bead of diaphragm therein.

Abstract: The present invention relates to a booster for automobile braking systems. The booster includes a booster housing with a movable wall disposed in the booster housing and dividing the interior of the housing into a constant pressure chamber connected to a vacuum source and a variable pressure chamber. A hub member is connected to the movable wall and has a projection extending air-tightly from the housing. The hub member is slidable relative to the housing. A control valve is disposed in the hub member and is manually actuated to interrupt fluid communication between the constant and vairable pressure chambers and to introduce ambient air into the variable pressure chamber thereby to generate an operational force of said movable wall. An output member transmits the operational force of the movable wall and the manual force applied to the control valve through a reaction force mechanism to an output arrangement.

Abstract: A fluid pressure servomotor including a housing, a partition wall arranged in the housing, a center hole formed in the partition wall, a hub member having a cylindrical portion, a ring bearing for axially slidably guiding the cylindrical portion and fitted in the hole. A sealing member is fitted in the hole and includes a sealing portion hermetically contacted with the partition wall and a lip portion hermetically contacted with the cylindrical portion. A retainer is provided for retaining the sealing member and the ring bearing between the partition wall and the cylindrical portion. The sealing member and the ring bearing are engaged with each other by engagement of a groove and a projection formed thereon, respectively, so that the sealing member and the cylindrical portion are maintained in a co-axial relationship.

Abstract: A vacuum booster including a push rod, a housing having a first and second compartments, a power piston located in the housing and operated by a pressure differential between the first and second compartments and including a small and large diameter opening portion, a control valve operatively associated with the push rod and located within the power piston for controlling the pressure differential between the first and second compartments in response to movement of the push rod, an output member having a rear end portion slidably disposed within the large diameter opening portion of the power piston, a valve plunger provided in the control valve and having one end slidably disposed in the small diameter opening of the power piston, a resilient reaction disc located adjacent the rear end portion of the output member and disposed within the large diameter portion of the power piston, and an elastic member disposed between the rear end portion of the output member and the power piston and defining a position of