Parking brake torque locking mechanism

Patent metadata

Field	Value
Publication number	US-10408289-B2
Application number	US-201715669037-A
Country	US
Kind code	B2
Filing date	Aug 4, 2017
Priority date	Aug 12, 2016
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

A brake system including a motor; a rotary to linear stage mechanism; and a torque locking mechanism. The rotary to linear stage mechanism in communication with the motor. The torque locking mechanism in communication with the motor. The torque locking mechanism comprises an electromagnet and a permanent magnet. During a brake apply the motor is adapted to move the rotary to linear stage mechanism so that at least one brake pad or at least one brake shoe is moved against a surface to create a clamp force. The electromagnet and the permanent magnet are adapted to cooperate to maintain the created clamp force.

First claim

The invention claimed is:

1. A brake system comprising:
a motor; and
a torque locking mechanism;
wherein during a brake apply, the torque locking mechanism is in an unlocked position allowing the motor to generate torque to move a brake pad or a brake shoe to generate a clamp force,
wherein after the motor ceases generating the torque, the torque locking mechanism moves into a locked position to restrict an output shaft of the motor from rotating and/or back driving, and
wherein the torque locking mechanism comprises an electromagnet, the electromagnet is supported on one or more pins, the electromagnet is configured to slide on the one or more pins between the locked position and the unlocked position.

2. The brake system of claim 1 , wherein the motor comprises a rotor,
wherein in the unlocked position, the electromagnet is spaced apart from the rotor; and
wherein in the locked position, the electromagnet is in contact with the rotor or in contact with one or more components that are in contact with the rotor.

3. The brake system of claim 2 , wherein the rotor is rotationally connected to the output shaft of the motor, the rotor comprises a magnet;
wherein during the brake apply, the electromagnet is adapted to generate a magnetic force that opposes a magnetic force generated by the magnet so that the electromagnet moves away from the magnet and into the unlocked position.

4. The brake system of claim 3 , wherein after the motor ceases generating the torque, the electromagnet ceases generating the magnetic force that opposes the magnetic force generated by the magnet and the electromagnet is magnetically attracted towards the magnet so that the electromagnet moves towards the magnet into the locked position.

5. The brake system of claim 4 , wherein the torque locking mechanism comprises a friction disc, and
wherein in the locked position, the electromagnet is in contact with the friction disc.

6. The brake system of claim 4 , wherein the electromagnet comprises a core and an electric coil, the core is rigidly connected to a housing of the motor so that the electromagnet is restricted from rotating.

7. The brake system of claim 3 , wherein the magnet is connected to the rotor and rotates with the rotor while the motor is generating the torque.

8. The brake system of claim 1 wherein the electromagnet comprises one or more pockets that are configured to receive a respective one of the one or more pins.

9. The brake system of claim 8 , wherein the one or more pockets are free from extending through an entire thickness of the electromagnet.

10. The brake system of claim 9 , wherein one or more vents are in contact with the one or more pockets.

11. The brake system of claim 1 , wherein the electromagnet is rigidly connected to a housing to restrict the electromagnet from rotating.

12. A brake system comprising:
a) a motor comprising a motor shaft;
b) a rotary to linear stage mechanism in communication with the motor; and
c) a torque locking mechanism comprising:
i) an electromagnet; and
ii) a permanent magnet,

wherein the electromagnet is moveably supported on one or more pins;
wherein during a brake apply, the electromagnet is adapted to generate a magnetic force that is adapted to repel a magnetic force of the permanent magnet so that the electromagnet axially moves in a direction away from the permanent magnet and into a spaced apart relationship with the permanent magnet so that the motor shaft is free to rotate and move the rotary to linear stage mechanism, and
wherein after the electromagnet ceases generating the magnetic force that is adapted to repel the magnetic force of the permanent magnet, the electromagnet is magnetically attracted toward the permanent magnet so that the electromagnet moves along the one or more pins and towards the permanent magnet so that the motor shaft locks and is unable to rotate.

13. A torque locking mechanism for preventing back driving of a motor in a brake system, the torque locking mechanism comprising a rotor and an electromagnet,
wherein while the motor is generating torque, the torque locking mechanism is in an unlocked position, and after the motor ceases generating the torque, the torque locking mechanism slides into a locked position and is configured to prevent the motor from back driving, and
wherein the rotor comprises a magnet that is configured to generate a magnetic force, the rotor is configured to rotate with an output shaft of the motor.

14. The torque locking mechanism of claim 13 , wherein while the motor is generating the torque, the electromagnet is magnetically repelled away from the rotor, and after the motor ceases generating the torque, the electromagnet is magnetically attracted towards the rotor.

15. The torque locking mechanism of claim 13 , wherein while the motor is generating the torque, the electromagnet is magnetically repelled away from the rotor, and after the motor ceases generating the torque, the electromagnet is magnetically attracted towards the rotor.

16. The torque locking mechanism of claim 13 , wherein the electromagnet is configured to slide along one or more pins.

17. The torque locking mechanism of claim 16 , wherein the electromagnet comprises a core, the core comprises one or more pockets that are each configured to receive one of the one or more pins.

18. The torque locking mechanism of claim 13 , wherein the rotor comprises a friction disc, and when the torque locking mechanism is in the locked position, the electromagnet is in contact with the friction disc, and when the torque locking mechanism is in the unlocked position the electromagnet is spaced apart from the friction disc.

19. A brake system comprising:
a motor comprising a rotor and an output shaft, the rotor is rotationally connected to the output shaft, the rotor comprises a magnet; and
a torque locking mechanism comprising an electromagnet;
wherein during a brake apply, the torque locking mechanism is in an unlocked position allowing the motor to generate torque to move a brake pad or a brake shoe to generate a clamp force; during the brake apply, the electromagnet is adapted to generate a magnetic force that opposes a magnetic force generated by the magnet so that the electromagnet moves away from the magnet and into the unlocked position;
wherein after the motor ceases generating the torque, the electromagnet ceases generating the magnetic force that opposes the magnetic force generated by the magnet and the electromagnet is magnetically attracted towards the magnet so that the electromagnet moves towards the magnet into a locked position to restrict the output shaft of the motor from rotating and/or back driving; in the locked position, the electromagnet is in contact with the rotor or in contact with one or more components that are in contact with the rotor.

20. The brake system of claim 19 , wherein the electromagnet comprises a core that is rigidly connected to a housing of the motor so that the electromagnet is restricted from rotating.

Assignees

• Akebono Brake Ind

Inventors

• Chelaidite Galus
• Al-Mahshi Waleed
• Thomas Carla

Classifications

• B60T13/748

  acting on electro-magnetic brakes (combined with fluid-pressure brake systems B60T13/667) · CPC title

• B60T13/741

  acting on an ultimate actuator · CPC title

• F16D2121/24

  using motors · CPC title

• F16D2125/34

  acting in the direction of the axis of rotation · CPC title

• F16D65/16

  arranged in or on the brake · CPC title