Hitachi Automotive Systems, Ltd.

Hitachi, Ltd.

Hitachi Astemo Ltd.

Ryohei Maruo

Chiharu Nakazawa

Masayuki Saito

Toshihiro Koizumi

Naganori Koshimizu

Toshiya Oosawa

Masaki Misunou

Hiroshi Owada

Takahiro Kawakami

Norihiro Saita

Asahi Watanabe

Hiroki Sonoda

Yoshiki Sakamoto

A stroke simulator is configured in such a manner that an elastic member disposed in a cylinder of the stroke simulator is restricted from being deformed in a radial direction of the cylinder.

Stroke simulator and brake control apparatus

Provided is a master cylinder unit including a simulator pressure chamber which communicates with a pressure chamber of a master cylinder and moves a simulator piston by means of an introduced fluid pressure; a biasing chamber in which a biasing mechanism biasing the simulator piston against a fluid pressure introduced into the simulator pressure chamber is disposed; a first seal member which partitions a simulator supply chamber, the simulator supply chamber, and the simulator pressure chamber communicating with a master supply chamber; and a second seal member which partitions the simulator supply chamber and the biasing chamber and allows a brake fluid to flow from the simulator supply chamber to the biasing chamber when a pressure difference occurs between the simulator supply chamber and the biasing chamber.

Master cylinder unit

Provided is a master cylinder unit including a communication path that causes a master cylinder and a stroke simulator to communicate with each other. The stroke simulator includes a bottomed tube-shaped simulator piston and a simulator cylinder in which a simulator piston slides. The simulator piston is such that a bottom portion of the simulator cylinder and an opening portion of the simulator piston face each other. The communication path is open over an outer circumferential portion and an inner circumferential portion of the opening portion of the simulator piston, is connected to the bottom portion of the simulator cylinder, and is provided such that the communication path extends upward in a vertical direction from the bottom portion of the simulator cylinder as approaching to a pressure chamber.

A brake apparatus is provided which has applicability to a wide range of vehicles. The brake apparatus includes a master cylinder provided in such a manner that a piston is axially operable in a master cylinder housing, and a stroke simulator including a reaction force piston axially operable by brake fluid introduced into a stroke simulator housing. The master cylinder housing is fixed to the stroke simulator housing. The stroke simulator housing is positioned between the master cylinder housing and a fixation piece structured to fix the stroke simulator housing to the vehicle. The fixation piece is spaced from the master cylinder housing.

Brake apparatus and brake system

An object of the present invention is to provide a brake apparatus that allows low-cost attachment of a stroke sensor that detects a stroke amount of a brake pedal. The brake apparatus is configured in such a manner that the stroke sensor that detects an amount of an axial stroke of a piston is disposed between one side surface of a master cylinder housing and one side surface of a valve housing, and an output of the stroke sensor is transmitted via a through-hole formed on the valve housing when being transmitted to a control unit attached to an opposite side surface-side of the valve housing.

Brake apparatus

A brake apparatus includes a brake operation member, a state detection unit, a cylinder, a first portion, an operation rod, a stepped piston, first, second, and third seal members, first and second pressure chambers, a hydraulic source, and first and second oil passages. The brake apparatus also includes a fluid amount control unit. The fluid amount control unit is configured to control an amount of the brake fluid to be supplied to the first pressure chamber and the second pressure chamber. The fluid amount control unit is also configured to increase the amount of the brake fluid to be supplied to the second pressure chamber when the detected state is equal to a preset pressure increase request.

A brake apparatus improved in mountability on a vehicle is provided. The apparatus includes a master cylinderthat generates hydraulic brake pressure by a driver's brake operation, and a stroke simulatorthat creates an artificial operation reaction force of a brake operation member when the brake fluid flown out of the master cylinderenters the stroke simulator. The master cylinderand the stroke simulatorare integrally arranged to overlap each other in a perpendicular direction (as viewed from the perpendicular direction) when installed in the vehicle.

A brake unit () includes: a master cylinder () unit which is fixed to a vehicle body, and which includes a master cylinder () that is received within a first housing (), and that is arranged to be interlocked with a brake pedal; and a pump unit () which is arranged to be driven by a motor (), and which includes a second housing () within which a pump arranged to increase a wheel cylinder pressure is received, the master cylinder unit () and the pump unit () being integrally fixed through a mount () which is an elastic member.

Brake unit

The present invention provides a brake device that can improve the pressure-increasing response of wheel cylinder hydraulic pressure. The invention is provided with: a master cylinder () actuated by the driver operating the brake, the master cylinder () being connected to a wheel cylinder () via a first oil channel (), and capable of increasing the wheel cylinder hydraulic pressure; and an auxiliary pressure-increasing part (auxiliary pressure-increasing part () and stroke simulator ()) for assisting in the increasing of the wheel cylinder hydraulic pressure by the master cylinder () of the pump ().

Brake device

Provided is a brake device that can increase energy efficiency. The present invention is provided with: a master cylinder () that generates fluid pressure alongside the operation of a brake by a driver; and a booster device that reduces the force of operation of the brake by the driver by means of an energy source (fluid pressure unit)). In a predetermined brake operation region, the operation of the booster device is suppressed.

A master cylinderincludes: a first liquid chambergenerating a liquid pressure in response to a brake operation of a driver; and a second liquid chambercommunicated with a reservoirand connected to a suction portof a pump. In a state in which the reservoirand a suction sectionof the pumpare communicated via the second liquid chamber, a liquid pressure of the first liquid chambercan create a wheel cylinder liquid pressure.

A gear pump includes: a drive shaft; a first gear; a second gear; a first plate disposed between the first gear and the second gear, and arranged to liquid-tightly seal the first surfaces of the first and second gear; a pair of second plates disposed, respectively, on the second surfaces of the first and second gears, and arranged to liquid-tightly seal the second surfaces of the first and second gears, each of the second plates including a tooth top sealing portion having a seal surface arranged to seal a tooth top of the first gear and a tooth top of the second gear, and to form a suction portion with the first plate and the second plate; and an urging member arranged to urge the drive shaft toward the seal surface of the tooth top sealing portion of one of the first and second plates.

Gear pump and gear pump for brake apparatus

A gear pump includes a gear to be driven by a drive shaft, a pair of side plate members adjoining side surfaces of the gear, respectively, to restrain leakage of an operating fluid, and a tip seal member or seal block for sealing the gear tip or circumference of the gear. At least one of the side plate members and the tip seal member are integral parts of a sealing member.

Gear pump

A seal apparatus includes at least one pair of gears; a side plate arranged adjacent to the pair of gears; and a housing sandwiching the side plate. At least one of the side plate and the housing includes a shoulder portion. The seal apparatus further includes a seal member arranged between the housing and the side plate and arranged at the shoulder portion. The seal member separates a low pressure area from a high pressure area in a radial direction of the gear. The shoulder portion is located in the low pressure area. At least a part of the seal member faces the high pressure area. The seal apparatus further includes a backup member reinforcing the seal member and facing a tip portion of the shoulder portion; and a containing portion formed between a root portion of the shoulder portion and the seal member to be capable of containing a part of the seal member at least when the seal member is elastically deformed.

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Kawasaki, Japan

Ryohei Maruo