Ntn Corporation

Mitsubishi Jidosha Kogyo Kabushiki Kaisha

Hitachi Astemo Ueda Co., Ltd.

Hitachi Astemo Ltd.

Yui Masuda

Tatsuya Yamasaki

Makoto Muramatsu

Toru Takahashi

Masaaki Eguchi

Hiromitsu Toyota

Hiromasa Satoh

Haruo Kotera

Yusuke Koga

Toshihiro Obika

Makoto Yasui

Yuki Saoyama

Yuuki Saoyama

Yasushi Aoki

Akiyoshi Nishikawa

A controller of an electric brake device includes first, second and third PKB operators. Upon receipt of an instruction to produce a parking brake active state while a parking brake is released, the first PKB operator exerts a braking force without depending on a brake pedal and determines if a desired braking force is exerted. After the determination by the first PKB operator, the second PKB operator makes a movable part ready to come into engagement with an engaged part and causes an electric motor to rotate in a direction in which the braking force is decreased, so that the movable part comes into engagement with the engaged part to prevent the rotation of the electric motor. Then, the third PKB operator produces the parking brake active state where no driving power is generated to the electric motor.

Electric brake device

The electric-powered actuator includes a control device including: a motor angle estimation unit, and a reverse-input holding control section having a function of engaging an engaging part with an engaged part by controlling a solenoid to set the reverse-input holding mechanism into a reverse-input holding state while the electric-powered actuator is applying a load and a function of, from the reverse-input holding state, disengaging the engaging part from the engaged part to set the reverse-input holding mechanism into a reverse-input holding release state. The reverse-input holding control section includes an engagement intermediate control function section configured to control the estimated rotation angle such that the engaged part and the engaging part come into a predetermined positional relation within a certain period of time, when the engaging part is brought into engagement with the engaged part and when the engaging part is brought out of engagement with the engaged part.

Electric-powered actuator and electric braking device

A vehicle brake system () includes a first control device () and a second control device () that respectively include a master controller (), a first sub-controller (), and a second sub-controller () that are connected to one another. Each of the master controller (), the first sub-controller (), and the second sub-controller () includes a braking force calculation unit that calculates braking force of electric brakes (to), and a determination unit that compares braking force calculation results of the controllers to determine whether itself is normal. The determination unit includes an output block section that blocks, when the determination unit determines that any one of the controllers is not normal, an output of the controller that is determined to be not normal.

Vehicle brake system

A highly reliable vehicle brake system that includes an electric brake and achieves redundancy at low cost is provided. A vehicle brake system () is provided to a wheel (Wa) of a vehicle (VB), and includes an electric brake () provided with a motor (), a driver () that drives the motor (), and a first control device () provided with a master controller () and a first sub-controller () connected to each other. The electric brake () is controllable by both the master controller () and the first sub-controller ().

Provided is an electric linear motion actuator that enables size reduction and cost reduction while increasing the instantaneous output of an electric motor. A control device () of the electric linear motion actuator includes: a motor driver () configured to control power supplied to a coil () of an electric motor (); a power storage unit () connected to a power supply device () and the motor driver (); a current flow direction restriction unit () disposed between the power supply device () and the power storage unit (), which causes current to pass only in a direction in which power is supplied from the power supply device (); and a step-up unit () configured to step up voltage of the power supply device () and provide the stepped-up voltage to the power storage unit ().

Electric linear actuator and electric brake device

A brake controller is provided with a positive efficiency operation limiter configured to provide a time for maintaining or decreasing a torque to be generated by a motor, such that a braking force generated by pressing between a brake rotor and friction pads does not decrease, while a braking force command value outputted from a braking force command section increases. For example, the limiter limits a ratio of a time for increasing the braking force, relative to a sum of the time for increasing the braking force and the time for maintaining or decreasing the braking force, to a predetermined value or less.

A highly reliable vehicle brake system including an electric brake is provided. A vehicle brake system () includes electric brakes (to) provided with motors (to), drivers (to) that drive the motors (to), and a control device that controls the drivers (to). The electric brake () includes two motors (and), and the control device includes separate drivers (and) respectively corresponding to the two motors (and). The control device includes a first master controller () and a first sub-controller (). The first master controller () controls the driver () corresponding to the motor (), and the first sub-controller () controls the driver () corresponding to the motor

The vehicle control device includes a speed calculation unit, a speed estimation unit, a motion feedback calculation unit, and a slip estimator. The speed calculation unit calculates a speed in a predetermined direction of a vehicle on the basis of a feature quantity. The speed estimation unit estimates a speed in the predetermined direction on the basis of a speed or acceleration detected by a motion detector. The motion feedback calculation unit performs feedback calculation in which a value obtained, through a proportional gain, from a deviation between a calculation speed calculated by the speed calculation unit and an estimation speed estimated by the speed estimation unit, is added to the feature quantity. The slip estimator compares the calculation speed with the estimation speed, and estimates that the vehicle is in a slip state in the predetermined direction, when the estimation speed exceeds the calculation speed.

Vehicle control device

The electric linear motion actuator includes an electric motor, a linear motion mechanism configured to convert rotary motion of the electric motor to linear motion of a linear motion part via a rotation input-output shaft, and a housing holding the linear motion mechanism. The electric motor includes a stator and a rotor which are arranged such that the directions of magnetic poles that generate interlinkage flux contributing to a motor torque are parallel with a rotation axis of the electric motor. The stator is arranged so as to be coupled with an axial end surface of the housing. The rotor is arranged so as to have a space, in the axial direction, from the torque generating surface of the stator, and the rotor is fixed to the rotation input-output shaft of the linear motion mechanism.

Electric linear motion actuator

A load sensor to be used in an electromechanical brake system includes a flange member capable of deflecting when receiving, at a load receiving portion, a load from the axially front side; a support member capable of supporting the flange member from the axially rear side, at a support portion displaced from the load receiving portion in a radial direction orthogonal to the axial direction; and a displacement detecting mechanism configured to detect the amount of relative movement between the flange and support members. A variable detection sensitivity mechanism enables the relative movement amount with respect to the change of the load applied to the flange member to be larger in a low load range in which the load is equal to or lower than a predetermined load value than in a high load range in which the load is higher than the predetermined load value.

Load sensor and electromechanical brake system

The linear motion mechanism and the electric motor are arranged in the axial direction with a rotary input-output shaft of the linear motion mechanism interposed therebetween. In the electric motor, orientation of a magnetic pole generating interlinkage flux is parallel with a rotation shaft of the motor. The linear motion mechanism has a thrust bearing for retaining a reaction force against a load in the axial direction in association with linear motion of the linear motion part. The control unit has a thrust force applying section for applying a thrust force such that a force acting in the axial direction of the rotary input-output shaft due to interlinkage flux between the stator and the rotor causes generation of a force, in the axial direction, acting on the thrust bearing.

The anti-lock brake control device includes: a wheel motion estimator to estimate one or more of an angle, an angular velocity, and an angular acceleration of a wheel; a slip estimator to estimate a slip state of the wheel, using an estimation result of the wheel motion estimator; and an anti-lock controller to give a command for causing a brake device to reduce a braking force, in accordance with the estimated slip state of the wheel. The slip estimator includes delay compensators, such as one or a plurality of filters, which perform delay compensation for the estimation result of the wheel motion estimator. The anti-lock controller gives the command for reducing the braking force, on the basis of a result of predetermined determination including comparison of the plurality of estimation results outputted from the slip estimator.

Anti-lock brake control device

Provided is an electric brake device that achieves improved responsiveness, cost reduction and also reduces the copper loss in an electric motor, thus reducing power consumption. The electric brake device includes a brake rotor (), a friction member (), a friction member actuator (), an electric motor (), a controller (), a main power supply (), and an auxiliary power supply (). The auxiliary supply () is charged with regenerative power from the motor (). The controller () includes a backflow power interruption () preventing the main supply () from being charged with the regenerative power from the motor (), and an auxiliary power supply controller () causing the auxiliary supply () to supply running power to the motor () when powering the electric () is started in a state in which the regenerative power in the auxiliary supply () is greater than or equal to a set voltage.

Electric brake apparatus and electric brake system

This electric brake device includes: a brake rotor, a friction member, a friction member operator, an electric motor, and a controller which controls, by controlling the electric motor, a braking force generated as a result of contact between the friction member and the brake rotor. The electric brake device includes a vehicle speed estimator which estimates the speed of the vehicle having the electric brake device mounted thereon. The controller includes a power limiter which limits the power that drives the electric motor. When an estimated vehicle speed, which is the speed of the vehicle estimated by the vehicle speed estimator, is in a determined low-speed range, the power limiter limits the power in accordance with a condition that has been determined such that the maximum power consumption of the electric brake device decreases in accordance with decrease in the estimated vehicle speed.

When a rotor performs an ordinary rotation operation, an axial position of the rotor is retained such that the rotor is rotatable with respect to a stator. When a parking brake switch is operated while a vehicle is at stoppage, a rotor slider slides the rotor in an axial direction against a preload of an axially preloading part. This brings an engaging portion of the rotor into engagement with an engaged portion of a housing. The reverse input holder retains the rotation angle of the rotor during the engagement due to the fact that the engagement between the engaging portion and the engaged portion is maintained against a reverse input load acting on the rotor as an external force that accompanies a reaction force of a pressing force of a brake friction member.

Growing community of inventors

Iwata, Japan

Yui Masuda