Electric brake device

Patent metadata

Field	Value
Publication number	US-2016200308-A1
Application number	US-201414915523-A
Country	US
Kind code	A1
Filing date	Aug 29, 2014
Priority date	Sep 4, 2013
Publication date	Jul 14, 2016
Grant date	—

Abstract

The electric brake device includes a brake rotor, a brake pad, an electric motor ( 2 ), a linear motion mechanism, and a controller ( 9 ). The controller ( 9 ) includes: a motor angular velocity control section ( 40 ) to control an angular velocity of the electric motor ( 2 ); and a motor angular velocity limiting section ( 41 ) to limit the angular velocity of the electric motor through the motor angular velocity control section ( 40 ) such that an angular velocity ωb of the electric motor ( 2 ) in a no-load state and an angular velocity ωr of the electric motor ( 2 ) in a no-load state satisfy |ωb|>|ωr| in which the angular velocity ωb is controlled by the motor angular velocity control section ( 40 ) when a state shifts from a non-braking state to a braking state, and the angular velocity ωr is controlled by the motor angular velocity control section ( 40 ) when the state shifts from the braking state to the non-braking state.

First claim

What is claimed is:

1 . An electric brake device comprising: a brake rotor; a brake pad; an electric motor; a linear motion mechanism configured to convert a rotary motion of the electric motor into a linear motion to transmit the linear motion to the brake pad; and a controller configured to control the electric motor, the controller comprising:
a motor angular velocity control section configured to control an angular velocity of the electric motor; and a motor angular velocity limiting section configured to limit the angular velocity of the electric motor through the motor angular velocity control section such that an angular velocity ωb of the electric motor in a no-load state and an angular velocity ωr of the electric motor in a no-load state satisfy |ωb|>|ωr| in which the angular velocity ωb is controlled by the motor angular velocity control section when a state shifts from a non-braking state where a clearance is formed between the brake pad and the brake rotor to a braking state where the clearance is zero, and in which the angular velocity ωr is controlled by the motor angular velocity control section when the state shifts from the braking state to the non-braking state.

2 . The electric brake device as claimed in claim 1 , wherein the motor angular velocity control section has a PWM control section configured to perform PWM control of the electric motor, and the motor angular velocity limiting section provides a command to the PWM control section so as to limit a PWM duty ratio, thereby to limit the angular velocity of the electric motor in the no-load state.

3 . The electric brake device as claimed in claim 1 , wherein the motor angular velocity control section has a PAM control section configured to perform PAM control of the electric motor, and the motor angular velocity limiting section provides a command to the PAM control section so as to limit an upper limit value of an amplitude of an output voltage, thereby to limit the angular velocity of the electric motor in the no-load state.

4 . The electric brake device as claimed in claim 1 , wherein the motor angular velocity control section has a PAM control section configured to perform PAM control of the electric motor, and the motor angular velocity limiting section provides a command to the PAM control section so as to limit a lower limit value of an amplitude of an output voltage, thereby to limit the angular velocity of the electric motor in the no-load state.

5 . The electric brake device as claimed in claim 1 , wherein the motor angular velocity control section has a frequency control section configured to control a frequency of a three-phase current to be applied to the electric motor, and the motor angular velocity limiting section provides a command to the frequency control section so as to limit a frequency of the three-phase current, thereby to limit the angular velocity of the electric motor in the no-load state.

Assignees

• Masuda Yui
• Ntn Toyo Bearing Co Ltd

Inventors

• Masuda Yui

Classifications

• F16D2125/40

  Screw-and-nut · CPC title

• B60T13/741 Primary

  acting on an ultimate actuator · CPC title

• F16D55/22

  by clamping an axially-located rotating disc between movable braking members, e.g. movable brake discs or brake pads · CPC title

• F16D2125/52

  with non-parallel stationary axes, e.g. worm or bevel gears · CPC title

• B60T1/065

  employing disc (B60T1/062 takes precedence) · CPC title