Drive mechanism for bicycle derailleur

Abstract

A drive mechanism for driving a bicycle derailleur via a gear cable. The drive mechanism includes a drive motor, a spindle, a fixed disc, a rotating disc, a cable reel, and a controller. The spindle is coupled to the output shaft of the drive motor and is rotatable by the drive motor. The fixed disc has a through hole and a plurality of first positioning portions disposed radially around the through hole; the spindle passes through the through hole and is rotatable relative to the fixed disc. The rotating disc is coupled to the spindle and has a plurality of second positioning portions. When the rotating disc rotates, the second positioning portions engage or disengage with corresponding first positioning portions. The cable reel is coupled to the spindle and rotates with the spindle; the cable reel is connected to the derailleur cable. The controller controls the rotation of the output shaft of the drive motor.

Claims

1. A drive device for driving a bicycle derailleur via a gear cable; the drive device comprising: a drive motor having an output shaft; a main shaft coupled to the output shaft of the drive motor and rotatable by the drive motor; a fixed disc having a first disc surface and a second disc surface facing away from each other, and a through hole penetrating the first disc surface and the second disc surface, the second disc surface facing away from the drive motor; the second disc surface having a plurality of first positioning portions disposed radially around the through hole; the main shaft passing through the through hole and rotatable relative to the fixed disc; a rotating disc coupled to the main shaft, the rotating disc rotating with the main shaft and having a plurality of second positioning portions; when the rotating disc rotates, the second positioning portions engaging or disengaging with corresponding first positioning portions to form a clutch structure; a cable reel coupled to the main shaft and rotatable with the main shaft, the cable reel being connected to the gear cable; and a controller electrically connected to the drive motor and controlling the rotation of the output shaft of the drive motor. in, The second positioning parts can move along the axis of the main shaft between a first position and a second position. When the second positioning parts are in the first position, they engage with the corresponding first positioning parts. When the second positioning parts are in the second position, they disengage from the corresponding first positioning parts.

2. The drive device as claimed in claim 1, wherein the rotating disk includes a disk body that is rotatable with the main shaft and axially movable along the main shaft; the second positioning portions are disposed on the side of the disk body facing the second disk surface; the disk body drives the second positioning portions to move between the first position and the second position.

3. The drive device as claimed in claim 2, wherein the disc body has a non-circular hole, the spindle has a coupling section, the shape of the outer peripheral surface of the coupling section being matched with the non-circular hole; the disc body is fitted onto the coupling section through the non-circular hole, and the disc body is movable along the axial direction of the spindle on the coupling section.

4. The drive device as described in claim 2, wherein each of the first positioning parts is a positioning groove and each of the second positioning parts is a positioning bead; when the positioning beads are in the first position, the positioning beads respectively enter the corresponding positioning groove to cooperate in positioning.

5. The drive device as claimed in claim 2, comprising an elastic element coupled to the disc body of the rotating disk and providing a biasing force on the disc body toward the second disc surface.

6. The drive device as claimed in claim 5, wherein the elastic element is a spring, the spring being sleeved on the main shaft and one end of the spring abutting against the disc body of the rotating disk, and the other end abutting against the winding reel.

7. The drive device as claimed in claim 6 includes a bearing comprising an outer ring and an inner ring, the inner ring being rotatable relative to the outer ring; a spindle is connected to the inner ring of the bearing, and a reel is located between the bearing and the spring; the reel abuts against the inner ring.

8. The drive device as claimed in claim 1, comprising a bearing located between the fixed disk and the drive motor and including an outer ring and an inner ring, the inner ring being rotatable relative to the outer ring; the spindle being connected to the inner ring of the bearing, and the fixed disk being connected to the outer ring of the bearing.

9. The drive device as claimed in claim 1, wherein the controller is configured to: receive a shift signal; in response to the shift signal, control the output shaft of the drive motor to rotate along one of a first rotation direction and a second rotation direction, wherein the first rotation direction is opposite to the second rotation direction; monitor a current change of the drive motor; determine a rotation angle based on the monitored current change; and in response to the rotation angle reaching a predetermined angle, control the drive motor to stop the output shaft from rotating.

10. The drive device as claimed in claim 9, wherein the shift signal is one of a first shift signal and a second shift signal; the controller, in response to the first shift signal, controls the output shaft of the drive motor to rotate in the first rotation direction; and the controller, in response to the second shift signal, controls the output shaft of the drive motor to rotate in the second rotation direction.

11. The drive unit as claimed in claim 9, the drive unit including a shift switch that is signal-connected to the controller and used to transmit the shift signal to the controller.

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