Toyota Jidosha Kabushiki Kaisha

Advics Co., Ltd.

Other

Toyota Jidoshi Kabushiki Kaisha

Yasuji Mizutani

Hiroshi Isono

Takayuki Yamamoto

Yoshio Masuda

Yusuke Kamiya

Kiyoyuki Uchida

Masaaki Komazawa

Akira Sakai

Motoshi Suzuki

Hirofumi Nitta

Eiji Nakamura

Hiroaki Niino

Masahiro Hara

Masaki Maruyama

Akitaka Nishio

Kazutaka Noro

Yosuke Yamasoe

Kouji Yotsuya

Tomihiro Wada

Hiroyuki Kodama

Yoshihisa Yamada

Akihiko Miwa

Hiroyuki Mizuno

Masayasu Ohkubo

Yasunori Sakata

Shirou Monzaki

Hiroshi Nakaoka

Yoshito Tanaka

Takashi Kurokawa

Koichi Takeuchi

Yutaka Onuma

Koichi Kondo

Osayoshi Kato

Yosuke Kuki

Kazuyoshi Sakazaki

A brake control device adjusts a front wheel braking hydraulic pressure of front wheel cylinders provided on front wheels of a vehicle and a rear wheel braking hydraulic pressure of rear wheel cylinders provided on rear wheels of the vehicle. The brake control device includes a hydraulic pressure generating unit configured to adjust a hydraulic pressure generated by an electric motor to an adjusted hydraulic pressure and apply the adjusted hydraulic pressure as the rear wheel braking hydraulic pressure and a hydraulic pressure correcting unit configured to adjust to decrease the adjusted hydraulic pressure to be a corrected hydraulic pressure, and apply the corrected hydraulic pressure as the front wheel braking hydraulic pressure.

Brake control device

A hydraulic brake system for braking a vehicle, including a master cylinder device having a fluid-flow permission mechanism that permits a flow of a working fluid between an inter-piston chamber and a low-pressure source, wherein, when a pressure of the working fluid to be supplied to a brake device exceeds a set pressure upon advancing in association with an advancing movement of a brake operation member, a closing and opening mechanism for hermetically closing the inter-piston chamber and opening an opposing chamber to the low-pressure source is controlled so as to hermetically close the inter-piston chamber, while, when the pressure of the working fluid becomes lower than a set pressure upon retracting in association with a retracting movement of the brake operation member, the fluid-flow permission mechanism is controlled so as to permit the flow of the working fluid between the inter-piston chamber and the low-pressure source.

Hydraulic brake system

The brake device for a vehicle generates two master pressures by controlling one single servo pressure to accurately control braking force. The pressure increasing characteristic is set based on the first pressure increasing characteristic obtained from the relationship between the servo pressure and the first master pressure upon increasing the servo pressure and the second pressure increasing characteristic obtained from the servo pressure and the second master pressure. The pressure decreasing characteristic is set based on the first pressure increasing characteristic obtained from the relationship between the servo pressure and the first master pressure upon decreasing the servo pressure and the second pressure decreasing characteristic obtained from the servo pressure and the second master pressure. Thus, the total braking force of the brake device is the sum of a braking force generated by the first master pressure and a braking force generated by the second master piston.

Brake device for vehicle

The vehicle brake system includes a cylinder, an output piston disposed in the cylinder, an input piston disposed in the cylinder but separating from the output piston and defining a separation chamber therebetween, a brake pedal connected to the input piston, a reaction force generating device for generating an elastic reaction force, a separation lock valve for controlling the communication between the separation chamber and the reaction force generating device, a fade state judging portion to judge whether the friction brake device is in a fade state or not and a friction braking force control portion for changing the mode to the fade state when the fade state judging portion judged that the friction brake device is in the fade state, wherein a desired friction braking force can be assured even under the brake fade state.

Vehicle brake system

A vehicle brake device is provided with a master cylinder, a master piston slidably arranged in the master cylinder, an input piston slidably arranged in the master cylinder to be separated from the master piston and defining a separation chamber, an input piston moving amount detecting section for detecting the moving amount of the input piston, a master piston moving amount calculating section for calculating the moving amount of the master piston based on the moving amount of the input piston, and a contact inferring section for inferring the contact of the input piston with the master piston based on the moving amount of the input piston and the moving amount of the master piston.

Vehicle brake device

A braking device for a vehicle includes an operating characteristics setting portion for setting an operating characteristic which is a relationship between the input electric power to the electro-magnetic valve and a pressure difference between a master cylinder side and a wheel cylinder side with respect to the electro-magnetic valve, based on the input electric power at the time when the accumulator pressure detected by the accumulator pressure detecting portion first falls to a value equal to or less than a threshold value accumulator pressure by changing the input electric power towards an opening side of the electro-magnetic valve in response to a time lapsed after a predetermined value of the pilot pressure has been generated by the pilot pressure generating portion by first closing the electro-magnetic valve thereby to suppress the manufacturing cost.

Braking device for vehicle

A vehicle brake system for braking a vehicle including a braking-mode switching mechanism configured to selectively effectuate, depending upon situations of the vehicle brake system, one of (A) a regulated-pressure-dependent braking mode in which is generated a regulated-pressure-dependent braking force having a magnitude that depends on a regulated pressure of a working fluid and (B) a braking mode depending on an operation force and the regulated pressure in which are generated both of an operation-force-dependent braking force having a magnitude that depends on the operation force by a driver and the regulated-pressure-dependent braking force.

The vehicle braking control device adapted to a vehicle brake device having an electromagnetic valve which controls the brake fluid flow between the master cylinder and the wheel cylinders in response to the input electric energy. The vehicle braking control device includes a valve opening electric energy obtaining portion which obtains an input electric energy upon opening of the electromagnetic valve as a valve opening electric energy and an operation characteristic setting portion which sets an operation characteristic based on the valve opening electric energy obtained corresponding to the predetermined pressure differential. The opening valve electric energy obtaining portion changes the input electric energy at a valve closing side or a valve opening side with a change amount per unit of time larger than before valve opening in response to an obtaining of the valve opening electric energy.

Vehicle braking control device

A vehicle hydraulic brake system of the brake-by-wire type includes input piston and a master piston configured to be actuated under hydraulic pressure introduced into a second fluid chamber and mounted in the housing so as to be movable relative to each other through a partition wall and a first fluid chamber. The piston defines therein a communication passage which extends from a fourth fluid chamber to the first fluid chamber and in which a check valve is mounted. When the piston is advanced under hydraulic pressure introduced into the second fluid chamber, the volume of the fourth fluid chamber decreases, while the volume of the first fluid chamber increases. This allows brake fluid in the fourth fluid chamber to be quickly released into the first fluid chamber through the communication passage and through a pipe line in which an electromagnetic on-off valve are mounted.

Hydraulic brake device for vehicle

A vehicle brake system includes a cylinder, a master piston including a pressure applying piston and a projection portion, a servo chamber, a contact/separation determining means determining a separated state and a contact state between the input piston and the master piston, a pilot pressure generating device generating a pilot pressure, a servo pressure generating device, a servo pressure measuring device measuring a servo pressure, and a master pressure estimating means estimating a master pressure from the pilot pressure and a first servo ratio, which is a cross-sectional area ratio between a first pilot chamber and a servo pressure generating chamber, in a case of the separated state, and estimating the master pressure based on the servo pressure, the pilot pressure and a second servo ratio, which is a cross-sectional area ratio between a second pilot chamber and the servo pressure generating chamber, in a case of the contact state.

In a brake control device and a brake control method, when a shift to a brake mode for backup involving separation of a supply path of working fluid is performed at the time of detection of an abnormality during braking, a differential pressure acting between an outlet opening and an inlet opening of an open-close valve which is provided between a hydraulic pressure source that is used during the backup brake mode and wheel cylinders and which needs to be opened during the backup brake mode is lessened prior to the separation of the supply path of working fluid so that the open-close valve is opened in accordance with a valve-opening command. Therefore, at the time of switch of the control mode, the confinement of wheel cylinder pressure is avoided.

Brake control device, and brake control method

A vehicular braking apparatus including a shut-off valve for shutting off, as needed, a flow of oil from a wheel cylinder to a master cylinder; a pressure increase-decrease control valve increasing and decreasing a pressure in the wheel cylinder; a reservoir receiving and storing in a reservoir chamber the oil from the wheel cylinder when the pressure increase-decrease control valve is in a pressure decrease position; a pump sucking in and pressuring the oil from the reservoir chamber and supplying the oil to the wheel cylinder via the pressure increase-decrease control valve when the pressure increase-decrease control valve is in a pressure increase position; and a communication control valve controlling communication between the master cylinder and the reservoir chamber. The communication control valve is a normally-closed valve and is opened by a suction pressure of the pump.

Vehicle brake device and its reservoir

First hydraulic-pressure supply piping extended from an accumulator is connected to a first supply port (that is, to a second pressure chamber) of a cylinder, and to second hydraulic-pressure delivery piping of an ABS via third hydraulic-pressure supply piping having a third linear valve. When the braking hydraulic pressure Pf is reduced in the ABS, the degree and the period of time that the third linear valve is opened are set according to the amount of fluid discharged from the second hydraulic-pressure delivery piping to a reservoir tank through a pressure-reducing valve so that a certain amount of fluid is returned from the first hydraulic-pressure supply piping to the second hydraulic-pressure delivery piping via the third hydraulic-pressure supply piping.

Vehicular brake system

A vehicle braking system including an input piston and a pressure piston that are moveably supported within a cylinder. The input piston is allowed to depress the pressure piston and is connected to the a brake pedal. Pressure chambers to the front and to the rear of the input piston are communicated through a communication passage such that the control hydraulic pressure in accordance with the operation amount to the brake pedal is applied to the second pressure chamber via first and second linear valves. The control hydraulic pressure in accordance with the operation amount to the brake pedal that has been transmitted to the pressure piston through the input piston is regulated by a pressure regulating valve so as to be applied to the second pressure chamber. The braking hydraulic pressure may be output from the pressure chambers, respectively.

Vehicle braking system

According to the braking force control system of the present invention it is prevented that the braking root pressure is increased unnecessarily high when the braking force increase suppressing control was initiated during the execution of the brake assist control without losing the effects of increasing the braking force available when the brake assist control only is executed. When the brake assist control is initiated, the pressure increase Pcf, Pcr of the braking root pressure of the front and rear wheels is increased relative to the master cylinder pressure Pm, but when the anti-skid control is executed for the left and right of the front or rear wheels, when the anti-skid control is executed for one of the front left and right wheels, while a yaw behavior control is executed for the other of the front left and right wheels, or when a braking force front/rear distribution control is executed, during the execution of the anti-skid control, the increase of the braking root pressure for the front or rear wheels is suppressed.

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Susono, Japan

Yasuji Mizutani