Electric brake device

Patent metadata

Field	Value
Publication number	US-10093290-B2
Application number	US-201615515395-A
Country	US
Kind code	B2
Filing date	May 10, 2016
Priority date	Jul 2, 2015
Publication date	Oct 9, 2018
Grant date	Oct 9, 2018

Abstract

An electric brake device has at least three control units: a first diagonal wheel control unit that controls a front-left wheel brake mechanism and a rear-right wheel brake mechanism which are positioned diagonally; a second diagonal wheel control unit that controls a front-right wheel brake mechanism and a rear-left wheel brake mechanism which are positioned diagonally; and a front wheel control unit that controls a front-left wheel brake mechanism and a front-right wheel brake mechanism. Each of the brake mechanisms has a friction-receiving member that rotates together with the wheel; and a friction-applying member that moves while being powered by an electric actuator, and obtains the braking force by pressing the friction-applying member against the friction-receiving member.

First claim

The invention claimed is:

1. An electric brake device for a vehicle that has a first wheel pair composed of a first wheel and a second wheel arranged leaving a space in between in a width direction of the vehicle, and a second wheel pair composed of a third wheel and a fourth wheel arranged leaving a space in between in the width direction, and arranged leaving a space from the first wheel pair in a length direction of the vehicle,
the device comprising:
a first control unit that controls only a first brake mechanism for braking the first wheel, and a third brake mechanism for braking the third wheel positioned diagonal to the first wheel;
a second control unit that controls only a second brake mechanism for braking the second wheel, and a fourth brake mechanism for braking the fourth wheel positioned diagonal to the second wheel; and
a third control unit that controls the first brake mechanism and the second brake mechanism,
wherein, when one of the first control unit and the second control unit is a failing control unit, the third control unit increases the braking force of one of the first brake mechanism and the second brake mechanism controlled by the failing control unit, while a non-failing control unit among the one of the first control unit and the second control unit increases the braking force of another one of the first brake mechanism and the second brake mechanism.

2. The electric brake device according to claim 1 ,
wherein each of the brake mechanisms comprises a friction-receiving member that rotates together with the wheel; and
the electric brake device further comprising:
a friction-applying member that moves while being powered by an electric actuator, and obtains the braking force by pressing the friction-applying member against the friction-receiving member.

3. The electric brake device according to claim 2 ,
wherein each of the brake mechanisms comprises a brake disk that rotates together with the wheel, and an electric caliper that has a brake pad movable between the pressing position and the non-pressing position relative to the brake disk by aid of the electric actuator.

4. The electric brake device according to claim 3 ,
wherein the third brake mechanism and the fourth brake mechanism also function as the parking brake mechanism, and
the parking control unit activates the parking brake by moving the brake pads of the third brake mechanism and the fourth brake mechanism to the pressing position relative to the brake disk.

5. The electric brake device according to claim 3 ,
wherein the parking brake mechanism comprises a brake drum that is provided in a hat positioned at the center of the brake disk of each of the third brake mechanism and the fourth brake mechanism, and is rotatable together with the wheel; and a brake shoe provided in each of the brake drums and movable between the pressing position and the non-pressing position relative to each brake drum by aid of an electric actuator for parking, and
the parking control unit activates the parking brake by moving the brake shoe of the parking brake mechanism to the pressing position relative to the brake drum.

6. The electric brake device according to claim 3 ,
wherein the parking brake mechanism comprises a brake drum that is provided in a hat positioned at the center of the brake disk of each of the third brake mechanism and the fourth brake mechanism, and is rotatable together with the wheel; and a brake shoe provided in each of the brake drums and movable between the pressing position and the non-pressing position relative to each brake drum by aid of a linear motion electric actuator, and
the parking control unit activates the parking brake by moving the brake shoe of the parking brake mechanism to the pressing position relative to the brake drum.

7. The electric brake device of claim 1 , wherein, in case of failure of the first control unit and the second control unit, the third control unit increases the braking force of each of the first brake mechanism and the second brake mechanism.

8. The electric brake device according to claim 7 , further comprising:
parking brake mechanisms that apply braking force to each of the third wheel and the fourth wheel; and
a parking control unit that controls the parking brake mechanisms,
wherein, in case of failure of the first control unit and the second control unit, the parking control unit activates the parking brake mechanisms to generate braking force for the third wheel and the fourth wheel.

9. The electric brake device according to claim 1 , wherein, in case of failure of the third control unit, the first control unit and the second control unit individually increase the braking force of their respective target front wheel brake mechanisms.

10. The electric brake device of claim 1 , wherein, in case that one of the first control unit and the second control unit, and the third control unit is the failing control unit, the non-failing control unit among one of the first control unit and the second control unit increases the braking force of another one of the first brake mechanism and the second brake mechanisms.

11. The electric brake device of claim 1 , wherein the first control unit additionally controls the second brake mechanism and the fourth brake mechanism, and
the second control unit additionally controls the first brake mechanism and the third brake mechanism.

12. The electric brake device of claim 1 , wherein the third control unit additionally controls the third brake mechanism and the fourth brake mechanism.

13. The electric brake device according to claim 1 ,
wherein each of the brake mechanisms is connected to a main battery and a backup battery that serve as power sources for controlling and activating the brake mechanisms, and, in case of main battery failure, the power source for each brake mechanism is switched to the backup battery.

14. The electric brake device according to claim 1 ,
wherein the first wheel is the front-left wheel, the second wheel is the front-right wheel, the third wheel is the rear-left wheel, and the fourth wheel is the rear-right wheel;
the first brake mechanism is the front-left wheel brake mechanism, the second brake mechanism is the front-right wheel brake mechanism, the third brake mechanism is the rear-left wheel brake mechanism, and the fourth brake mechanism is the rear-right wheel brake mechanism; and
the first control unit is a first diagonal wheel control unit, the second control unit is a second diagonal wheel control unit, and the third control unit is a front wheel control unit.

Assignees

• Mitsubishi Motors Corp

Inventors

• Kotera Haruo
• Toyota Hiromitsu

Classifications

• B60T1/067

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

• F16D2121/24

  using motors · CPC title

• B60T2270/402

  Back-up · CPC title

• B60T8/3255

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

• B60T1/065

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