Abstract: A braking device for a vehicle includes a cylinder, a master piston having a pressure applying piston portion and a servo pressure receiving portion, an input piston, a pressure accumulating device, a pilot pressure generating device, and a regulator having a first piston slidably fitted into a housing and dividing an inside of the housing into a first pilot chamber and a servo pressure generating chamber, a valve mechanism connecting the servo pressure generating chamber with the pressure accumulating device or a reservoir in response to movement of the first piston, and a second piston fitted into the housing and dividing the inside of the housing into the first pilot chamber and a second pilot chamber, wherein the second piston is formed so that an end surface thereof exposed to the first pilot chamber has a larger pressure-receiving surface area than an end surface exposed to the second pilot chamber.

Abstract: A fluid pressure booster and a fluid pressure brake apparatus having the fluid pressure booster are provided. The fluid pressure booster includes an auxiliary fluid pressure source including a power-operated pump and a pressure accumulator, a pressure adjusting device which adjusts fluid pressure supplied from the auxiliary fluid pressure source to a value corresponding to an operating amount of a brake operation member by displacement of a spool valve and introduces the adjusted fluid pressure into a boost chamber, a boost piston which receives the fluid pressure introduced into the boost chamber to generate assist force and operates a master piston of a master cylinder by assisted force, and a damper chamber which communicates with one or both of the boost chamber and a pressure chamber of the master cylinder.

Abstract: A vehicle brake device is provided with a regulator for generating a servo pressure acting on a master piston in a master cylinder, based on a pilot pressure. The regulator is provided with a brake fluid absorbing section communicating with a first pilot chamber for absorbing the brake fluid as the pilot pressure in the first pilot chamber in the quantity depending on the fluid pressure in the first pilot chamber. The brake fluid absorbing section comprises a piston receiving portion formed in a second piston and opening to the first pilot chamber, a pressure receiving piston slidably received in the piston receiving portion and making the first pilot chamber variable in capacity, and an urging member urging the pressure receiving piston toward the first pilot chamber side.

Abstract: A braking device for a vehicle includes a cylinder, a master piston having a pressure applying piston portion and a servo pressure receiving portion, an input piston, a pressure accumulating device, a pilot pressure generating device, and a regulator having a first piston slidably fitted into a housing and dividing an inside of the housing into a first pilot chamber and a servo pressure generating chamber, a valve mechanism connecting the servo pressure generating chamber with the pressure accumulating device or a reservoir in response to movement of the first piston, and a second piston fitted into the housing and dividing the inside of the housing into the first pilot chamber and a second pilot chamber, wherein the second piston is formed so that an end surface thereof exposed to the first pilot chamber has a larger pressure-receiving surface area than an end surface exposed to the second pilot chamber.

Abstract: A vehicle brake device is provided with a regulator for generating a servo pressure acting on a master piston in a master cylinder, based on a pilot pressure. The regulator is provided with a brake fluid absorbing section communicating with a first pilot chamber for absorbing the brake fluid as the pilot pressure in the first pilot chamber in the quantity depending on the fluid pressure in the first pilot chamber. The brake fluid absorbing section comprises a piston receiving portion formed in a second piston and opening to the first pilot chamber, a pressure receiving piston slidably received in the piston receiving portion and making the first pilot chamber variable in capacity, and an urging member urging the pressure receiving piston toward the first pilot chamber side.

Abstract: An electric connecting structure between a substrate and an electric component includes a substrate mounted in a case, an electric component assembled to a member which the case is mounted, a bus bar fixed to the case and connected to an electric circuit on the substrate at its one end and a spring disposed in compressed state between the bus bar and an electrode formed on the electric component. The substrate is electrical lyconnected to the electric component through the bus bar and the spring and a held portion formed on the spring is held by a spring holding portion integrally formed on the bus bar.

Abstract: A hydraulic brake system is proposed which includes a hydraulic booster for boosting brake operation, and a circulation type pressure control unit. The hydraulic brake system further includes a hydraulic booster including an auxiliary hydraulic pressure source, a pressure regulator for adjusting the hydraulic pressure supplied therefrom to a value corresponding to an operating amount of a brake operating member and introducing the thus adjusted hydraulic pressure into a boost chamber, and a boost piston for actuating a master piston with a force boosted by an assisting force generated by the hydraulic pressure introduced into the boost chamber. The hydraulic booster further includes a hydraulic line bypassing the pressure regulator and extending from the boost chamber to the auxiliary hydraulic pressure, and a check valve provided in the hydraulic line and configured to allow only a discharge of hydraulic pressure from the boost chamber into the auxiliary hydraulic pressure source.

Abstract: A hydraulic brake apparatus includes a master cylinder pressurizing brake fluid in a pressure chamber and outputting a hydraulic pressure to a wheel cylinder of a first brake circuit, and a pressure control valve controlling a hydraulic pressure of an auxiliary hydraulic pressure source outputting the controlled hydraulic pressure to a wheel cylinder of a second brake circuit, wherein a master cylinder piston includes a first passage which hydraulically connects the pressure chamber and a reservoir, and a switching valve which closes and opens the first passage, and wherein a throttle means and a check valve, which allows the brake fluid to travel only from the reservoir to the pressure chamber, are hydraulically provided in parallel with each other at the first passage at a position between the switching valve and the reservoir.

Abstract: A hydraulic brake system is proposed which includes a hydraulic booster for boosting brake operation, and a circulation type pressure control unit. The hydraulic brake system further includes a hydraulic booster including an auxiliary hydraulic pressure source, a pressure regulator for adjusting the hydraulic pressure supplied therefrom to a value corresponding to an operating amount of a brake operating member and introducing the thus adjusted hydraulic pressure into a boost chamber, and a boost piston for actuating a master piston with a force boosted by an assisting force generated by the hydraulic pressure introduced into the boost chamber. The hydraulic booster further includes a hydraulic line bypassing the pressure regulator and extending from the boost chamber to the auxiliary hydraulic pressure, and a check valve provided in the hydraulic line and configured to allow only a discharge of hydraulic pressure from the boost chamber into the auxiliary hydraulic pressure source.

Abstract: A fluid pressure booster and a fluid pressure brake apparatus having the same are provided. The fluid pressure booster includes an auxiliary fluid pressure source having a pump and a pressure accumulator, a pressure adjusting device which adjusts fluid pressure supplied from the auxiliary fluid pressure source to a value corresponding to an operating amount of a brake operation member by displacement of a spool valve and introduces the same into a boost chamber, a boost piston which receives the fluid pressure introduced into the boost chamber to generate assist force and operates a master piston of a master cylinder by assisted force, and a displacement absorption member which is provided at a position to which thrust force of the master piston is applied, and which is compressed in an axial direction when transfer power between the boost piston and the master piston exceeds a setting value.

Abstract: A fluid pressure booster and a fluid pressure brake apparatus having the fluid pressure booster are provided. The fluid pressure booster includes an auxiliary fluid pressure source including a power-operated pump and a pressure accumulator, a pressure adjusting device which adjusts fluid pressure supplied from the auxiliary fluid pressure source to a value corresponding to an operating amount of a brake operation member by displacement of a spool valve and introduces the adjusted fluid pressure into a boost chamber, a boost piston which receives the fluid pressure introduced into the boost chamber to generate assist force and operates a master piston of a master cylinder by assisted force, and a damper chamber which communicates with one or both of the boost chamber and a pressure chamber of the master cylinder.

Abstract: A hydraulic brake apparatus includes a master cylinder pressurizing brake fluid in a pressure chamber and outputting a hydraulic pressure to a wheel cylinder of a first brake circuit, and a pressure control valve controlling a hydraulic pressure of an auxiliary hydraulic pressure source outputting the controlled hydraulic pressure to a wheel cylinder of a second brake circuit, wherein a master cylinder piston includes a first passage which hydraulically connects the pressure chamber and a reservoir, and a switching valve which closes and opens the first passage, and wherein a throttle means and a check valve, which allows the brake fluid to travel only from the reservoir to the pressure chamber, are hydraulically provided in parallel with each other at the first passage at a position between the switching valve and the reservoir.

Abstract: An actuator for use in a vehicle hydraulic brake system having an anti-lock control and/or vehicle stability control function has a housing which also serves as the body of the master cylinder. The housing is formed with four wheel cylinder ports to be connected to the respective wheel cylinders through pipes. Since there is usually enough space in front of the housing, all of the wheel cylinder ports are formed in the front end face of the housing so that the pipes can be arranged in the large space in front of the actuator. The ports are arranged in the width direction of the vehicle with the ports at both ends located at a higher level than the other ports. With this arrangement, pipes can be easily mounted to and dismounted from the ports at both ends by turning a spanner without the possibility of the spanner interfering with components in the engine room, such as a relay box or the engine.

Abstract: A center valve for a master cylinder includes a valve body and a valve seat fitted in a valve casing. The valve seat has an elastic tube fitted on a core member. The elastic tube has a front end portion adapted to be pressed against the rear end face of the valve body, and a rear cylindrical portion. A gap is provided behind the cylindrical portion of the elastic tube. When the front end of the elastic tube is deformed, the cylindrical portion of the tube is also deformed in such a way as to fill or protrude into the gap. Because the rear cylindrical portion is also deformed, the degree of deformation of the front end is suppressed. This prevents the front end of the tube from getting trapped between the valve body and the core member of the valve seat and thus getting torn.

Abstract: A center valve for a master cylinder includes a valve body and a valve seat fitted in a valve casing. The valve seat has an elastic tube fitted on a core member. The elastic tube has a front end portion adapted to be pressed against the rear end face of the valve body, and a rear cylindrical portion. A gap is provided behind the cylindrical portion of the elastic tube. When the front end of the elastic tube is deformed, the cylindrical portion of the tube is also deformed in such a way as to fill or protrude into the gap. Because the rear cylindrical portion is also deformed, the degree of deformation of the front end is suppressed. This prevents the front end of the tube from getting trapped between the valve body and the core member of the valve seat and thus getting torn.

Abstract: An actuator for use in a vehicle hydraulic brake system having an anti-lock control and/or vehicle stability control function has a housing which also serves as the body of the master cylinder. The housing is formed with four wheel cylinder ports to be connected to the respective wheel cylinders through pipes. Since there is usually enough space in front of the housing, all of the wheel cylinder ports are formed in the front end face of the housing so that the pipes can be arranged in the large space in front of the actuator. The ports are arranged in the width direction of the vehicle with the ports at both ends located at a higher level than the other ports. With this arrangement, pipes can be easily mounted to and dismounted from the ports at both ends by turning a spanner without the possibility of the spanner interfering with components in the engine room, such as a relay box or the engine.

Abstract: The present invention is directed to a hydraulic brake apparatus capable of reducing a hysteresis caused by increase and decrease of braking input force, wherein a regulator chamber is defined ahead of a control piston, and a counter-force pressure chamber is defined to communicate with the regulator chamber. An auxiliary pressure source is provided for supplying hydraulic brake pressure to the counter-force pressure chamber, to move a pressure increase valve and a pressure decrease valve in a direction opposite to a direction thereof moved by the control piston. A first check valve is provided for normally preventing the flow of brake fluid from the counter-force pressure chamber to the regulator chamber, and allowing the reverse flow of brake fluid when the pressure in the regulator chamber has become equal to or more than the pressure in the counter-force pressure chamber by a first predetermined pressure.

Abstract: A vehicular braking force control apparatus includes a solenoid valve disposed between a master cylinder and the suction side of a hydraulic pump. A ripple absorption low-pressure reservoir is provided between the solenoid valve and the suction side of the hydraulic pump. The low-pressure reservoir is partitioned, by a partition member, into an operation liquid portion that communicates with an auxiliary suction passage and an air portion where air exists. A spring member for pressing the partition member toward the operation liquid portion side is provided in the air portion.

Abstract: The present invention is directed to a hydraulic pressure control unit, which includes a housing having hydraulic passages defined therein, and a plurality of electromagnetic valves having valve mechanisms disposed in the hydraulic passages and solenoid coil portions mounted on one wall of the housing for actuating the valve mechanisms. The electromagnetic valves include four large electromagnetic valves provided with cylindrical solenoid coil portions, each having a relatively large diameter, and eight small electromagnetic valves provided with cylindrical solenoid coil portions, each having a relatively small diameter. And, two rows of four small electromagnetic valves aligned in a row are located in parallel with each other on the wall of the housing, and two rows of two large electromagnetic valves aligned in a row are located in parallel with the two rows of the four small electromagnetic valves.