Toyota Jidosha Kabushiki Kaisha

Advics Co., Ltd.

Toyoto Jidosha Kabushiki Kaisha

Naoki Yabusaki

Yoshiyuki Yasui

Hiroyuki Kodama

Masaki Nanahara

Shinichiro Yukoku

Shinsuke Yamamoto

Ryutaro Misumi

Satoshi Hirata

Tomohiko Takeda

Nao Ikuma

Hiroshi Isono

Takayuki Yamamoto

Takahisa Yokoyama

Akira Sakai

Tsukasa Fukasawa

Yuta Morikawa

Takahiro Shiraki

Masaharu Ohba

Tsuyoshi Ando

Yusuke Oshio

Tsuyoshi Andou

Shun Nohira

Minoru Nakajima

Mitsuyasu Mizuno

Kenichi Hasegawa

Takuya Hirano

Teppei Onodera

A brake device for a vehicle includes a fluid supply portion that supplies a fluid to a wheel cylinder utilizing the fluid in a reservoir and is configured such that a piston presses brake pads against a disc rotor to apply a braking force to a wheel. The brake device includes: a fluid level sensor configured to measure a value of a fluid level in the reservoir and a controller including one or more processors and configured to: estimate a wear amount of the brake pads based on a result of measurement by the fluid level sensor; estimate a heat generation amount of the brake pads based on the result of measurement; and determine whether a fluid leakage is occurring based on i) an amount of change in the fluid level that is based on the result of the measurement, ii) the wear amount, and iii) the heat generation amount.

Brake device for vehicle

A vehicle brake system including a regenerative cooperative control device configured to control a regenerative brake device that applies a regenerative braking force to one of front and rear wheels and/or a friction brake device that applies a friction braking force to the front and rear wheels. After the regenerative braking force reaches an allowable regenerative braking force, the friction braking force applied to the other of the front and rear wheels is increased by the friction brake device up to a first friction braking force less than a braking force on an actual braking-force distribution line determined by the regenerative braking force at a time when it reaches the allowable regenerative braking force, and the friction braking forces applied to the one and the other of the front and rear wheels are subsequently increased so as to bring the friction braking forces close to the actual braking-force distribution line.

Vehicle brake system

A vehicle brake system, including: a wheel brake device including an actuator including a piston, a working fluid chamber, an electric motor, and a piston moving mechanism; a working-fluid supply device; and a controller configured to execute: a normal brake control to control a hydraulic braking force to a magnitude corresponding to a braking request; and a parking brake control to cause the wheel brake device to be operated as a parking brake, wherein, in the parking brake control, the controller controls the wheel brake device to generate the hydraulic braking force at a start timing of an operation as the parking brake, controls the actuator to perform a lock operation in which the electric motor is operated to move the piston forward in a state in which the hydraulic braking force is generated, and controls the wheel brake device to release the hydraulic braking force after the lock operation.

Brake system

A control device executes caster angle change control for controlling a driving force applying device or each of the driving force applying device and a braking force applying device to reduce a caster angle of a steered tire-wheel assembly when a steering request is received in a stopped state or in a creeping state without exceeding a predetermined vehicle speed at a point starting from the stopped state. In the caster angle change control, the control device applies, to one tire-wheel assembly out of a front tire-wheel assembly and a rear tire-wheel assembly, a driving force in a direction toward the other tire-wheel assembly and applies, to the other tire-wheel assembly, a braking force or a driving force in a direction toward the one tire-wheel assembly to achieve the stopped state or the creeping state in response to a request for acceleration or deceleration.

Vehicle control system

A brake actuator includes: a housing; an electric motor with a hollow motor shaft rotating; a rotating shaft disposed inside the motor shaft to be coaxial therewith; a piston with a rear end disposed inside the motor shaft and a front end engaged with the friction member; a speed reduction mechanism decelerating rotation transmitted from the motor shaft and transmitting the rotation to the rotating shaft; and a motion conversion mechanism converting a rotating motion of the rotating shaft into an advancing/retracting motion of the piston. The motor shaft is rotatably supported by the housing at an outer peripheral surface thereof, and the rotating shaft is rotatably supported by an inner peripheral surface of the motor shaft via rollers at an outer peripheral surface thereof as well as by the housing via a thrust bearing at a rear end of the rotating shaft.

Brake actuator

An electric brake actuator configured to push a friction member onto a rotary body by advancing a piston by rotating an input shaft by an electric motor, including: a torque imparting device configured to impart, to an input shaft, a torque in a direction to retract a piston based on an elastic torque of a torsion spring and including a mechanism configured to allow a first retained portion provided at one end portion of the torsion spring to be retained by another one of a plurality of first retaining portions of a stator when the elastic torque exceeds a set upper-limit torque to decrease the elastic torque; and a mechanism configured to permit a second retained portion of a rotor to be retained by a second retaining portion provided at the other end portion of the spring to prohibit the elastic torque from becoming smaller than a set lower-limit torque.

Electric brake actuator

This electric braking device for a vehicle imparts to the wheels of the vehicle a braking torque in accordance with the output of an electric motor. A vehicle body-side electronic control unit calculates a command value for the output of the electric motor on the basis of the amount of operation performed on a braking operation member. A wheel-side electronic control unit adjusts the output of the electric motor on the basis of the command value. The vehicle body-side electronic control unit calculates the vehicle body speed on the basis of the wheel speed. The wheel-side electronic control unit adjusts the output of the electric motor so as to prevent an increase in slippage of the wheels on the basis of the vehicle body speed and the wheel speed.

Electric braking device for vehicle

An electric brake control apparatus includes: a clamping force acquisition unit configured to acquire a clamping force generated by moving a piston toward a pad through rotation of a motor; a lower-limit clamping force acquisition unit configured to acquire a minimum value of the clamping force required to maintain a stopped state of the rotor; an upper-limit clamping force acquisition unit configured to acquire a maximum value of the clamping force to move the piston away from the pad through a power of a power supply while maintaining the stopped state of the rotor, based on a state of a power supply; and a clamping force control unit configured to control the motor such that the clamping force is confined between the minimum value and the maximum value.

Electric brake control apparatus

An electric brake caliper, including: a caliper main body; brake pads; and an actuator including a piston, an electric motor of a rotary type, and a motion converting mechanism, wherein the motion converting mechanism includes a hollow output sleeve configured to be linearly moved to move the piston disposed at one end of the output sleeve nearer to the one of the brake pads and an input shaft disposed in the output sleeve and configured to be rotated by the electric motor, the motion converting mechanism being configured to convert rotation of the input shaft into a linear movement of the output sleeve, wherein the electric motor includes a hollow driving rotary shaft, and wherein the motion converting mechanism is disposed in the driving rotary shaft, and the input shaft includes a flange whose outer circumferential end is in mesh with an inner circumferential portion of the driving rotary shaft.

Electric brake caliper

A vehicle brake system, including: an electric brake device including a friction member, a rotor, a motor, and a driven member; and a wear detector including a data obtaining section to obtain a forward movement amount of the driven member and a pressing force by which the driven member presses the friction member, a detecting section to detect a contact start position of the driven member, and an estimating section to estimate a remaining thickness of the friction member, wherein the wear detector includes an uneven-wear detecting section to detect uneven wear of the friction member, by comparing: a relationship between the forward movement amount and the pressing force; and a relationship therebetween in a case where it is supposed that a thickness of the friction member is equal to the remaining thickness that would be estimated in a state in which the friction member is evenly worn.

Vehicle brake system and method of detecting wear of friction member

A vehicle brake control device generates rear wheel braking torque by an electric motor by pressing a friction member against a rotating member rotating together with the rear wheel, reduces rear wheel braking torque by controlling the electric motor based on a target energization amount calculated from a slip state quantity of the rear wheel, and rapidly stops electric motor rotation motion based on an adjusted target energization amount calculated from the target energization amount and a slip state quantity of a front wheel.

Braking control device for vehicle

A mount member is fixed to a support member by first and second fastening members, and a caliper is mounted to the mount member by first and second guide members. A motor axis of an electric motor and an axis of a shaft member configured to press a pressing member are different from each other. The electric motor is fixed to the caliper. When viewed from an axial direction of the first guide member, the motor axis is positioned inside a fastening quadrangle having four corners corresponding to positions of respective axes of, and is perpendicular to the axis, and the motor axis is orthogonal to a plane of the fastening quadrangle. As a result, there may be provided a vehicle electric braking device in which an axial direction dimension may be reduced to suppress an amplitude caused by vibration, and components sensitive to vibration influence are appropriately arranged.

Vehicle electric braking device

A vehicle brake apparatus capable of preventing abnormal vibration due to thickness variations in a disc rotor includes a motor drive unit configured to control the motor which presses the brake pad against the disc rotor, a brake pressure detection unit for detecting a braking pressure for pressing the brake pad, and a wheel speed sensor for detecting a rotation speed of the disc rotor. If an amount of variation in the detection values detected by the brake pressure detection unit during one rotation of the disc rotor exceeds a variation amount determination threshold value and a detection value variation frequency has a correlation with the rotation speed of the disc rotor and the detection value variation frequency exceeds a variation frequency determination threshold value, the motor drive unit controls the motor in inverted phase to the variation in the detection values.

Vehicle brake apparatus

Each of a plurality of electric brake devices corresponds to one of a plurality of wheels and includes a motor. A brake ECU, which controls the electric brake devices, determines whether there is an overheated motor of which the temperature T is greater than or equal to a first set threshold value Tth. Also, when there is only one overheated motor, the brake ECU reduces a current value Ix for the overheated motor at a more gradual gradient in the case where the temperature T of the overheated motor is low than in the case where the temperature is high.

Vehicle braking control device

An EPB-ECU is an electric parking brake control device which generates a braking force by driving an electric motor to press pads and to a disc rotor. The EPB-ECU includes a current supply unit for supplying a motor current to the electric motor and stopping the supply of the motor current when the motor current reaches a predetermined target current value, a supply time measurement unit for measuring a supply time of the motor current, a waiting time setting unit for setting a waiting time from when the supply of the motor current is stopped to when the supply of the motor current is restarted next time on the basis of the measured motor current supply time, and a control unit for instructing the current supply unit to supply the motor current according to the set waiting time.

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Toyota, Japan

Naoki Yabusaki