BRAKE DEVICE FOR HUMAN-POWERED VEHICLE

Abstract

A brake device is provided to a human-powered vehicle. The brake device includes an input body, a brake, and a power converter. A driving force is input to the input body. The brake is configured to contact a rotational body of the human-powered vehicle. The power converter is configured to convert a rotational force of the input body to a force that moves the brake toward the rotational body. The power converter includes a transmission configured to change a ratio of a movement amount of the brake to an output rotational speed of the input body.

Description

Claims

1. A brake device for a human-powered vehicle, the brake device comprising: an input body to which a driving force is input;a brake configured to contact a rotational body of the human-powered vehicle; anda power converter configured to convert a rotational force of the input body to a force that moves the brake toward the rotational body,the power converter including a transmission configured to change a ratio of a movement amount of the brake to an output rotational speed of the input body.

2. The brake device according to claim 1, wherein the transmission is configured to change the ratio between a first ratio and a second ratio that differs from the first ratio.

3. The brake device according to claim 2, wherein the transmission is configured to set the ratio to the first ratio in a case where the brake is moved toward the rotational body until the brake contacts the rotational body and set the ratio to the second ratio as the brake comes into contact with the rotational body.

4. A brake device for a human-powered vehicle, the brake device comprising: an input body to which a driving force is input;a brake configured to contact a rotational body of the human-powered vehicle; anda power converter configured to convert a force of the input body to a force that moves the brake toward the rotational body,the power converter including a transmission configured to change a ratio of a movement amount of the brake to an output amount of the input body, andthe transmission being configured to set the ratio to a first ratio in a case where the brake is moved toward the rotational body until the brake contacts the rotational body, and the transmission being configured to set the ratio to a second ratio that differs from the first ratio as the brake comes into contact with the rotational body.

5. The brake device according to claim 2, wherein the transmission is configured to change the ratio from the first ratio to the second ratio in accordance with a reaction force produced as the brake comes into contact with the rotational body in a case where the brake is moved toward the rotational body.

6. The brake device according to claim 2, wherein the transmission is configured to set the ratio to the second ratio in a state in which the brake is in contact with the rotational body, and the transmission is configured to set the ratio to the first ratio as the brake separates from the rotational body in a case where the brake is moved away from the rotational body.

7. The brake device according to claim 2, wherein the transmission is configured to maintain the ratio at the second ratio with a reaction force applied to the brake by the rotational body in a case where the brake is moved away from the rotational body and the brake is in contact with the rotational body.

8. The brake device according to claim 2, wherein the first ratio is greater than the second ratio.

9. The brake device according to claim 2, wherein the transmission is configured to transmit a rotational force of the input body to the brake through one of a first transmission path configured to set the ratio to the first ratio and a second transmission path configured to set the ratio to the second ratio.

10. The brake device according to claim 9, wherein: the input body includes an input rotational shaft, a first input rotational body provided on the input rotational shaft, and a second input rotational body provided on the input rotational shaft and having an outer diameter that differs from that of the first input rotational body;the first input rotational body is configured to transmit a rotational force to the first transmission path; andthe second input rotational body is configured to transmit a rotational force to the second transmission path.

11. The brake device according to claim 10, further comprising: a housing, wherein: the power converter includes a first shaft that has a first center axis and that is rotatable relative to the housing, a first rotational body that is provided on the first shaft and engaged with the first input rotational body, a second rotational body that is provided on the first shaft and engaged with the second input rotational body, a first converter that is provided on the first shaft and that converts rotational motion to linear motion, and a second converter that is provided on the first shaft and that converts rotational motion to linear motion;the first shaft is configured to be movable relative to the first rotational body and the second rotational body in a direction parallel to the first center axis; andthe brake is provided on an end of the first shaft in the direction parallel to the first center axis.

12. The brake device according to claim 11, wherein: the first converter includes a first engagement portion and a second engagement portion;the first engagement portion is provided on the first rotational body at a portion that differs from a portion engaged with the first input rotational body;the second engagement portion is provided on the first shaft in a manner movable relative to the first shaft in the direction parallel to the first center axis and engaged with the first engagement portion;one of the first engagement portion and the second engagement portion includes a female thread; andthe other one of the first engagement portion and the second engagement portion includes a male thread.

13. The brake device according to claim 12, wherein: the first engagement portion includes the male thread, andthe second engagement portion includes the female thread.

14. The brake device according to claim 12, wherein the transmission includesa first restriction mechanism configured to restrict rotation of the second engagement portion relative to the housing, anda second restriction mechanism configured to restrict movement of the second engagement portion relative to the first engagement portion in the direction parallel to the first center axis.

15. The brake device according to claim 14, wherein: the first restriction mechanism is configured to permit rotation of the second engagement portion relative to the housing in a case where a torque input to the second engagement portion is greater than or equal to a first torque;the first restriction mechanism is configured to restrict rotation of the second engagement portion relative to the housing in a case where the torque input to the second engagement portion is less than the first torque;the second restriction mechanism is configured to restrict movement of the second engagement portion relative to the first engagement portion in the direction parallel to the first center axis in a case where the torque input to the second engagement portion is greater than or equal to a second torque; andthe second restriction mechanism is configured to permit movement of the second engagement portion relative to the first engagement portion in the direction parallel to the first center axis in a case where the torque input to the second engagement portion is less than the second torque.

16. The brake device according to claim 12, wherein: the second converter includes a third engagement portion provided on the first shaft in a manner nonrotatable relative to the housing, and a fourth engagement portion provided on the first shaft;the third engagement portion is configured to be moved relative to the first shaft integrally with the second engagement portion in the direction parallel to the first center axis; andthe fourth engagement portion is configured to be moved relative to the first shaft and the second engagement portion in the direction parallel to the first center axis.

17. The brake device according to claim 16, wherein the second rotational body, the first rotational body, the second engagement portion, the third engagement portion, the fourth engagement portion, and the brake are provided on the first shaft in order of the second rotational body, the first rotational body, the second engagement portion, the third engagement portion, the fourth engagement portion, and the brake in the direction parallel to the first center axis.

18. The brake device according to claim 1, further comprising: an electric actuator configured to transmit the driving force to the input body.

19. The brake device according to claim 18, further comprising: a speed reducer provided between the electric actuator and the input body.

20. The brake device according to claim 18, further comprising: a rotation restriction mechanism provided between the electric actuator and the input body to restrict rotation of the input body in a case where output torque of the electric actuator is greater than or equal to a third torque.

21. The brake device according to claim 1, further comprising: a disc brake including a disc rotor,wherein the rotational body includes the disc rotor.