Electric brake system and electric brake device

Patent metadata

Field	Value
Publication number	US-10710562-B2
Application number	US-201715817905-A
Country	US
Kind code	B2
Filing date	Nov 20, 2017
Priority date	May 21, 2015
Publication date	Jul 14, 2020
Grant date	Jul 14, 2020

Abstract

A brake integrated control section generates, as target values, a target braking force and a target wheel speed equivalent value of each electric brake device, and transmits the target braking force and the target wheel speed equivalent value to a target value transmitter. An electric brake control device of each electric brake device includes a braking force controller that controls an electric motor in accordance with the target braking force, a wheel speed controller that controls the electric motor in accordance with the target wheel speed equivalent value, and a control switcher. The control switcher switches between use of the braking force controller and use of the wheel speed controller in accordance with a predetermined condition.

First claim

What is claimed is:

1. An electric brake system comprising:
a plurality of electric brake devices each including an electric brake actuator that includes a brake rotor, a friction member, a friction member operator configured to bring the friction member into contact with the brake rotor, and an electric motor configured to drive the friction member operator, and an electric brake control device configured to control the electric motor;
a brake integrated control section configured to generate target values for controlling each of the electric brake control devices; and
a target value transmitter configured to transmit the generated target values to each of the electric brake control devices, wherein
the brake integrated control section generates, as the target values, a target braking force and a target wheel speed equivalent value of each of the electric brake devices, and transmits the target braking force and the target wheel speed equivalent value to the target value transmitter,
each of the electric brake control devices includes a braking force controller configured to control the electric motor in accordance with the target braking force, a wheel speed controller configured to control the electric motor in accordance with the target wheel speed equivalent value, and a control switcher configured to switch between use of the braking force controller and use of the wheel speed controller in accordance with a predetermined condition,
the brake integrated control section includes a wheel speed instruction section configured to estimate, from a wheel speed equivalent value estimated by a wheel speed estimator, a limit value of the wheel speed equivalent value for preventing an excessive slip state of a wheel, and use the limit value as the target wheel speed equivalent value, and
the control switcher of the electric brake control device selects control performed by the braking force controller using the target braking force included in the target values if the wheel speed equivalent value estimated by the wheel speed estimator does not exceed the target wheel speed equivalent value, and selects control performed by the wheel speed controller using the target wheel speed equivalent value included in the target values if the wheel speed equivalent value exceeds the target wheel speed equivalent value.

2. An electric brake system comprising:
a plurality of electric brake devices each including an electric brake actuator that includes a brake rotor, a friction member, a friction member operator configured to bring the friction member into contact with the brake rotor, and an electric motor configured to drive the friction member operator, and an electric brake control device configured to control the electric motor;
a brake integrated control section configured to generate target values for controlling each of the electric brake control devices; and
a target value transmitter configured to transmit the generated target values to each of the electric brake control devices, wherein
the brake integrated control section generates, as the target values, a target braking force and a target wheel speed equivalent value of each of the electric brake devices, and transmits the target braking force and the target wheel speed equivalent value to the target value transmitter,
each of the electric brake control devices includes a braking force controller configured to control the electric motor in accordance with the target braking force, a wheel speed controller configured to control the electric motor in accordance with the target wheel speed equivalent value, and a control switcher configured to switch between use of the braking force controller and use of the wheel speed controller in accordance with a predetermined condition,
the brake integrated control section includes a wheel speed instruction section configured to estimate, from a wheel speed equivalent value estimated by a wheel speed estimator, a non-slip wheel speed equivalent value that is a wheel speed equivalent value in synchronization with a vehicle body speed, and use the non-slip wheel speed equivalent value as the target wheel speed equivalent value,
the electric brake control device includes a limit value estimator configured to estimate, from the wheel speed equivalent value estimated by the wheel speed estimator and the non-slip wheel speed equivalent value, a limit value of a wheel speed equivalent value for preventing an excessive slip state, and
the control switcher selects control performed by the braking force controller using the target braking force included in the target values if the wheel speed equivalent value estimated by the wheel speed estimator does not exceed the limit value of the wheel speed equivalent value, and selects control performed by the wheel speed controller using the target wheel speed equivalent value included in the target values if the wheel speed equivalent value exceeds the limit value.

3. The electric brake system as claimed in claim 1 , wherein
the braking force controller of the electric brake control device has an interpolation function of interpolating the target wheel speed equivalent value at an intermediate time in an update interval of the target wheel speed equivalent value.

4. The electric brake system as claimed in claim 1 , wherein
the brake integrated control section is provided in a control device provided separately from the electric brake control device.

5. The electric brake system as claimed in claim 1 , wherein
the brake integrated control section is provided in one of the electric brake control devices of the plurality of electric brake devices.

6. The electric brake system as claimed in claim 1 , wherein
the target value transmitter is a serial communicator configured to transmit a predetermined number of bits as one transmission frame, and each of the target braking force and the target wheel speed equivalent value is transmitted in a predetermined bit interval.

7. The electric brake system as claimed in claim 1 , wherein
the target value transmitter is a serial communicator configured to transmit a predetermined number of bits as one transmission frame,
the transmission frame contains: a target value that is one of the target braking force and the target wheel speed equivalent value; and identification information indicating which of the target braking force and the target wheel speed equivalent value the target value is, and
the control switcher recognizes, on the basis of the identification information, which of the target braking force and the target wheel speed equivalent value the transmitted target value is.

8. An electric brake device comprising:
an electric brake actuator including a brake rotor, a friction member, a friction member operator configured to bring the friction member into contact with the brake rotor, and an electric motor configured to drive the friction member operator; and
an electric brake control device configured to control the electric motor, wherein
the electric brake device includes a braking force controller configured to control the electric motor in accordance with the target braking force, a wheel speed controller configured to control the electric motor in accordance with a target wheel speed equivalent value, and a control switcher configured to switch between use of the braking force controller and use of the wheel speed controller in accordance with a predetermined condition, and
the control switcher is configured to select control performed by the braking force controller using the target braking force included in the target values if a wheel speed equivalent value estimated by a wheel speed estimator does not exceed the target wheel speed equivalent value, and select control perf

Assignees

• Ntn Toyo Bearing Co Ltd

Inventors

• Masuda Yui

Classifications

• B60T13/741

  acting on an ultimate actuator · CPC title

• B60T13/662

  characterised by specified functions of the control system components · CPC title

• B60T8/3255

  Systems in which the braking action is dependent on brake pedal data · CPC title

• B60T7/042

  by electrical means, e.g. using travel or force sensors · CPC title

• B60T8/17 Primary

  Using electrical or electronic regulation means to control braking {(detecting or indicating faulty operation B60T8/885)} · CPC title