Electric brake device

Patent metadata

Field	Value
Publication number	US-11001246-B2
Application number	US-201916365204-A
Country	US
Kind code	B2
Filing date	Mar 26, 2019
Priority date	Sep 28, 2016
Publication date	May 11, 2021
Grant date	May 11, 2021

Abstract

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.

First claim

What is claimed is:

1. An electric brake device comprising:
an electric actuator and a controller,
the electric actuator including
a brake rotor,
a friction member to be brought into contact with the brake rotor,
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,

the controller being configured to control, by controlling the electric motor, a braking force generated as a result of the contact between the friction member and the brake rotor, wherein
the electric brake device comprises a vehicle speed estimator configured to estimate a speed of a vehicle having the electric brake device mounted thereon,
the controller includes a power limiter configured to limit a power that drives the electric motor, and
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 so a maximum power consumption of the electric brake device decreases in accordance with a decrease in the estimated vehicle speed, and thereby performs a control for keeping a total sum of maximum power consumptions of electric devices mounted on the vehicle, including the electric brake device, constant over an entire vehicle speed range.

2. The electric brake device as claimed in claim 1 , wherein
the controller includes an angular velocity estimator configured to estimate an angular velocity of a rotor of the electric motor, and has a function of determining, when controlling the braking force, a torque to be outputted by the electric motor or a value corresponding to the torque, and
in accordance with the estimated vehicle speed, the power limiter changes a limitation value for the torque or the value corresponding to the torque at a determined estimated angular velocity among angular velocities estimated by the angular velocity estimator.

3. The electric brake device as claimed in claim 2 , wherein
the electric brake device comprises a plurality of the electric actuators,
the controller controls the plurality of the electric actuators, and
the power limiter changes a limitation value for a total sum of the torques outputted by the electric motors or of the values corresponding to the torques.

4. The electric brake device as claimed in claim 1 , wherein
the controller has a function of controlling, when controlling the braking force, a voltage that is related to a current of the electric motor, and
the power limiter limits the voltage such that a power derived from the current and the voltage or a value corresponding to the power does not exceed a determined limit value.

5. The electric brake device as claimed in claim 4 , wherein
the electric brake device comprises a plurality of the electric actuators,
the controller controls the plurality of the electric actuators, and
the power limiter changes a limitation value for a total sum of the powers derived from the currents and the voltages or of the values corresponding to the powers.

6. The electric brake device as claimed in claim 1 , wherein
the power limiter limits the power only when the electric motor performs power-running operation.

Assignees

• Ntn Toyo Bearing Co Ltd

Inventors

• Masuda Yui

Classifications

• B60T8/52 Primary

  Torque sensing, i.e. wherein the braking action is controlled by forces producing or tending to produce a twisting or rotating motion on a braked rotating member · CPC title

• H02P29/00

  Arrangements for regulating or controlling electric motors, appropriate for both AC and DC motors (arrangements for starting electric motors H02P1/00; arrangements for stopping or slowing electric motors H02P3/00; control of motors that can be connected to two or more different electric power supplies H02P4/00; regulating or controlling the speed or torque of two or more electric motors H02P5/00; vector control H02P21/00) · CPC title

• B60T13/74

  with electrical assistance or drive · CPC title

• B60T8/00

  Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force (by changing number of effective brake cylinders in power brake systems B60T17/10) · CPC title

• B60T13/741 Primary

  acting on an ultimate actuator · CPC title