Advics Co., Ltd.

Toyota Jidosha Kabushiki Kaisha

Koichi Kokubo

Masayuki Naito

Masahiro Matsuura

Shigeru Saito

Yuji Sengoku

Kazuya Maki

Takayuki Yamamoto

Hiroaki Niino

Yukio Mori

Tetsuya Miyazaki

Shun Tsukamoto

Koichi Hashida

Masahiro Hara

Masayoshi Takeda

Masaki Maruyama

Yoshio Masuda

Takahiro Yamaguchi

Shinichiro Yukoku

Yuji Yoshii

Hiroyuki Matsubayashi

Motokazu Ishikawa

Hidehiro Yamauchi

Takeshi Hato

Yusuke Morikawa

Jun Shinozaki

According to one embodiment, for example, when it is determined that a certain condition has been satisfied while first antilock control is being executed, a controller of a brake control apparatus executes second antilock control by opening and closing a solenoid valve with a motor stopped so that brake fluid of the wheel cylinder is caused to flow into a reservoir, the second antilock control including a second pressure reduction mode, the second pressure reduction mode reducing a pressure of a wheel cylinder while substantially equilibrating the pressure of the wheel cylinder and a pressure of the reservoir at a certain pressure or larger, the certain pressure being larger than zero.

Brake control apparatus

Provided is an electric braking device that transmits power generated by an electric motor MTR to a pressing member PSN and causes pressing force to be generated by the pressing member PSN with respect to a friction member MSB. Hysteresis characteristics in the relation between the power supply amount to the electric motor and the pressing force of the pressing member are detected each time a predetermined point in time arrives. Upon determination of a 'holding state in which the pressing force is held constant', a minimum value for a power supply amount that makes it possible to maintain the current pressing force is obtained on the basis of the most recently detected hysteresis characteristics and the power supply amount is set to a value determined on the basis of the obtained minimum value for the power supply amount.

Electric braking device for vehicle

An electric braking device includes: a first valve unit for adjusting a first differential pressure between a master cylinder side liquid pressure and a wheel cylinder side liquid pressure; a storage unit forming a fluid storage chamber; second valve units for adjusting a second differential pressure between the master cylinder side liquid pressure and a storage chamber side liquid pressure; an electric pump for discharging the fluid in the storage chamber; and a control unit which, while operating the electric pump during a time from initiation of braking force application until a request value acquired by a request braking force acquiring unit reaches a maximum value, controls the first valve unit such that the first differential pressure becomes zero, and controls the second valve units such that the second differential pressure becomes zero.

Braking device for vehicle

A braking control device includes a first wheel cylinder on either the left or right front wheel side of a vehicle; a second wheel cylinder on the other side; a first pressure-regulating mechanism that pressurizes the brake fluid inside the first wheel cylinder; a second pressure-regulating mechanism that pressurizes brake fluid inside the second wheel cylinder; and a normally-closed opening/closing valve interposed in a connecting fluid path connecting the first wheel cylinder and the second wheel cylinder and in which, if a sudden operation is determined, the opening/closing valve is put in a connected state and increases the pressure of the brake fluid inside the first and second wheel cylinders by the first and second pressure-regulating mechanisms.

Braking control device for vehicle

In an electric braking device for a vehicle, the following are carried out in order: a first lock process in which either torque for shifting the ratchet gear in a release direction is generated in an electric motor or the driving of the electric motor is stopped, while a pawl member is being pressed against a ratchet gear; a second lock process in which the rotational angle of the ratchet gear is brought to an angle different from a semi-engaging rotational angle by driving the electric motor; and a third lock process in which the ratchet gear is rotated in the release direction by driving the electric motor in reverse.

Braking-force-maintaining device for vehicle and electric braking device for vehicle

A braking apparatus according to an embodiment includes: a fluid pressure circuit that is provided between a master cylinder and a wheel cylinder, and that includes both a first system flow channel connecting a reservoir and at least one of the plurality of wheel cylinders, and a second system flow channel connecting at least one of the plurality of wheel cylinders and the master cylinder, and that forms a flow channel for supplying operating fluid to each of the wheel cylinders; and a pump provided in the first system flow channel and driven by the motor to increase the fluid pressure of the operating fluid to be supplied from the reservoir to the wheel cylinders. A control unit controls the driving state of the pump in order to drive, when a predetermined fail standard for braking control has been satisfied, the motor in accordance with the information detected by an operating state detection means, and executes fail-safe control for providing braking force by supplying the operating fluid discharged from the pump to the fluid pressure chamber in the master cylinder.

Braking apparatus

In a braking control apparatus, a plurality of pumps are driven by a common first motor. A brake supplies operating fluid to pipelines by operating the first motor, and controls opening/closing of a fluid pressure regulating valve so as to make the wheel cylinder pressure in the right front wheel approach the right front wheel target pressure, and controls opening closing of a fluid pressure regulating valve so as to make the wheel cylinder pressure in the left rear wheel approach the left rear wheel target pressure. In the case where the right front wheel target pressure is zero when the fluid pressure regulating valve is to be opened so as to make the wheel cylinder pressure in the left rear wheel approach the left rear wheel target pressure, the brake turns off the first motor.

Braking control apparatus

A braking apparatus for a vehicle includes a hydraulic brake apparatus generating a basic hydraulic pressure so that a basic hydraulic braking force is generated at wheels, the hydraulic brake apparatus generating a controlled hydraulic pressure so that a controlled hydraulic braking force is generated at the wheels, a regenerative brake apparatus causing a regenerative braking force to be generated at any of the wheels, and braking force replacement controlling means for gradually replacing the regenerative braking force with the controlled hydraulic braking force while braking during which at least the regenerative braking force is applied for a purpose of achieving a braking force replacement control to ensure a total braking force required for the wheels by decreasing the regenerative braking force at a gradient within a predetermined range and by increasing the controlled hydraulic braking force in response to the decrease of the regenerative braking force.

Braking apparatus for vehicle

A braking control device which adjusts fluid pressure according to the degree of opening of a proportional electromagnetic valve driven at a set drive frequency, and controls a braking force on the basis of the adjusted fluid pressure, comprises a required pressure adjustment precision index setting mechanism for setting a required pressure adjustment precision index on the basis of the precision of pressure adjustment required when the fluid pressure is adjusted according to a required braking force, required operating noise reduction index setting mechanism for setting a required operating noise reduction index on the basis of a requirement to reduce operating noise caused by the drive frequency for driving the proportional electromagnetic valve, and drive frequency setting mechanism for setting the drive frequency of the proportional electromagnetic valve on the basis of the set required pressure adjustment precision index and required operating noise reduction index.

Braking control device

A braking control apparatus includes a brake operating member, a hydraulic circuit supplying a wheel cylinder hydraulic pressure to a wheel cylinder, a pump generating a hydraulic pressure so that the wheel cylinder hydraulic pressure reaches a value in response to an operation of the brake operating member, a circulation conduit provided at a portion of the hydraulic circuit, the circulation conduit through which a partial amount of brake fluid discharged from the pump is circulated back to the pump, a pressure regulating valve adjusting a pressure difference between an upstream side of the pressure regulating valve connected to the wheel cylinder and a downstream side, and a controlling device calculating, on the basis of a circulation flow rate of the brake fluid passing through the pressure regulating valve, an applied current to the pressure regulating valve for obtaining a target of the pressure difference and controlling the applied current.

A vehicle brake system is provided with a brake ECU serving as controlled hydraulic brake force control for executing a controlled hydraulic brake force control to decrease the rotational speed of an electric motor when at least both of a regenerative brake force and a controlled hydraulic brake force are being applied. The brake ECU decreases the rotational speed of the electric motor when the gradient of a target controlled hydraulic brake force being a controlled hydraulic pressure command value given to a hydraulic brake device is downhill or is not present. Thus, the pressured fluid supplied from a pump driven by the electric motor to be supplied to wheel cylinders of a vehicle is decreased to enhance the efficiency in utilizing the regenerative energy which an electric motor for driving the vehicle has in dependence on the stepping state of a brake pedal.

Vehicle brake system

A vehicle brake system, capable of realizing a brake-by-wire construction which can be installed in vehicles in the same manner as conventional brake systems, is provided with a booster device, a master cylinder, wheel brakes, and a hydraulic pressure control device interposed between the master cylinder and the wheel brakes. The system is further provided with a stroke sensor for detecting the moving stroke of a brake pedal, a simulator for applying to the brake pedal a pseudo reaction force corresponding to the moving stroke of the brake pedal, a play or idling component arranged between the booster device and the hydraulic pressure control device for absorbing the moving stroke of the brake pedal by a predetermined amount, and an electronic control device for controlling the hydraulic pressure control device based on an input from the stroke sensor.

A control unit of a brake apparatus includes a compensation braking force controlling device for controlling a compensation braking force in response to an operation of a brake operating member so that a characteristic of a total braking force relative to the operation of the brake operating member agrees with a predetermined target characteristic. The total braking force is a sum of the compensation braking force containing a pressurizing hydraulic braking force based upon at least the pressurization and a basic hydraulic pressure braking force based upon the basic hydraulic pressure. The compensation braking force controlling device includes: a judging device for judging whether the vehicle has stopped, and a limiting device for limiting the amount of pressurization via a pressure control valve when the judging device determines that the vehicle has stopped.

Control unit of brake apparatus for vehicle

A brake apparatus for a vehicle generally sets an upper limit value of regenerative braking force to the maximum value of the regenerative braking force which can be generated at the present. In the case of a front-wheel-drive vehicle, the total braking force, the sum of front-wheel braking force (front-wheel hydraulic braking force+regenerative braking force) and rear-wheel braking force (rear-wheel hydraulic braking force), is rendered coincident with a target braking force corresponding to a brake pedal depressing force, and the regenerative braking force is set to a largest possible value equal to or less than the upper limit value. As a result, the regenerative braking force can be larger than front-wheel-side target distribution braking force. The upper limit value is decreased from the maximum value by an amount corresponding to the degree of easiness of occurrence of a locking tendency at the driven wheels (front wheels).

Brake control apparatus for vehicle

A vehicle deceleration control device is provided that can determine an appropriate supplemental braking force when a braking force is applied according to an accelerator operation state. An engine braking-equivalent braking force is varied according to an initial accelerator angle when an accelerator returns and according to an accelerator return speed. That is, the greater the initial accelerator angle is, or the greater the accelerator return speed is, the greater the value to which the engine braking-equivalent braking force is set. It therefore becomes possible to determine the appropriate supplemental braking force that reflects the driver's braking intention.

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Nagoya, Japan

Koichi Kokubo