JP-7856425-B2 - Drive unit for human-powered vehicles

Inventors

• 中島 康博
• 永田 紀一郎
• 高山 仁志

Assignees

• 株式会社シマノ

Dates

Publication Date

20260511

Application Date

20211224

Claims (13)

1. A drive unit for a human-powered vehicle, A motor having a motor rotation shaft, A power connection part connected to the motor rotating shaft, An output rotating unit connected to the motor rotating shaft via the power connection unit, The system includes a control unit configured to control the motor, The aforementioned power connection part is A first rotating body having a rotational axis, A second rotating body is positioned coaxially with the first rotating body, with respect to the axis of rotation, at least a portion of which overlaps the first rotating body radially, and is connected to the motor via the first rotating body. The first rotating body includes an intermediate transmission body disposed between the first rotating body and the second rotating body in the radial direction of the first rotating body, The intermediate transmission body includes a plurality of rolling elements, When the motor rotation shaft rotates in the first motor rotation direction, a first connection state is permitted in which the driving force of the motor input to the first rotating body is transmitted to the output rotating part, The connection state of the power connection is configured to be switchable between a second connection state in which the transmission of the external driving force to the motor is permitted when the output rotating part rotates in the rotation direction of the first output rotating part by an external driving force, and The control unit switches the connection state between a first connection state and a second connection state by controlling the motor. The output rotating section is configured to be coaxial with the crankshaft, and is a drive unit.
2. The power connection section further includes a reduction gear, The drive unit according to claim 1, wherein the first rotating body, the second rotating body, and the intermediate transmission body are provided in the reduction gear.
3. The drive unit according to claim 1 or 2, wherein the power connection section is configured such that the second connection state is maintained by restricting the relative rotation between the first rotating body and the second rotating body in the second connection state.
4. A drive unit for a human-powered vehicle, A motor having a motor rotation shaft, A power connection part connected to the motor rotating shaft, An output rotating unit connected to the motor rotating shaft via the power connection unit, The system includes a control unit configured to control the motor, The aforementioned power connection part is Includes a clutch and a reduction gear having at least one rotating shaft, When the motor rotation shaft rotates in the first motor rotation direction, a first connection state is permitted in which the driving force of the motor input from the power connection part is allowed to be transmitted to the output rotation part, The connection state of the power connection is configured to be switchable between a second connection state in which the transmission of the external driving force to the motor is permitted when the output rotating part rotates in the rotation direction of the first output rotating part by an external driving force, and The aforementioned clutch is It includes a first rotating body, a second rotating body, and an intermediate transmission body. The first rotating body, the second rotating body, and the intermediate transmission body are immovable in the axial direction with respect to at least one rotation axis. The control unit is a drive unit that switches the connection state between a first connection state and a second connection state by controlling the motor.
5. The drive unit according to any one of claims 1 to 4, wherein, when the connection state is the first connection state, the control unit controls the motor to generate a torque that rotates the motor rotation shaft in a second motor rotation direction opposite to the first motor rotation direction, thereby switching the connection state from the first connection state to the second connection state.
6. The drive unit according to any one of claims 1 to 5, wherein, when the connection state is the second connection state, the control unit controls the motor to generate a first torque that rotates the motor rotation shaft in the first motor rotation direction, thereby switching the connection state from the second connection state to the first connection state.
7. The drive unit according to any one of claims 1 to 5, wherein, when the connection state is the second connection state, the control unit controls the motor to generate a second torque that rotates the motor rotation shaft in the first motor rotation direction, and then controls the motor to decrease the second torque, thereby switching the connection state from the second connection state to the first connection state.
8. The drive unit according to any one of claims 1 to 7, wherein, when the connection state is the first connection state, and a braking request is made to the human-powered vehicle, the control unit controls the motor to switch the connection state from the first connection state to the second connection state.
9. The aforementioned human-powered vehicle further includes a battery, The drive unit according to any one of claims 1 to 8, wherein the control unit is configured to charge the battery with the power generated by the motor.
10. The drive unit according to any one of claims 1 to 9, further comprising an input rotating section connected to the output rotating section and configured to receive human-powered driving force.
11. The drive unit according to claim 10, wherein the output rotating section is arranged coaxially with the input rotating section.
12. The drive unit according to claim 10 or 11, further comprising a one-way clutch configured to allow the transmission of the human-powered driving force to the output rotating part when the input rotating part rotates in the rotational direction of the first input rotating part, and to suppress the transmission of the motor's driving force to the input rotating part when the motor's rotating shaft rotates in the rotational direction of the first motor.
13. The drive unit according to any one of claims 10 to 12, wherein the input rotating part includes a crankshaft.

Description

This disclosure relates to a drive unit for a human-powered vehicle. For example, the drive unit for a human-powered vehicle disclosed in Patent Document 1 includes a motor that performs regenerative braking. Japanese Patent Publication No. 2018-158695 This is a block diagram showing the power transmission path of a human-powered vehicle, including a drive unit for a human-powered vehicle according to an embodiment.This is a block diagram showing the transmission path of the motor's driving force in Figure 1.Figure 1 is a block diagram showing the electrical configuration of a human-powered vehicle, including the drive unit for the human-powered vehicle.Figure 3 is a perspective view of a drive unit for a human-powered vehicle.Figure 4 is a side view of a drive unit for a human-powered vehicle.This is a cross-sectional view along the line D6-D6 in Figure 5.Figure 6 is a cross-sectional view showing a part of the clutch.Figure 6 shows a cross-sectional view of a part of the clutch when it is in the first connected state.Figure 6 shows a cross-sectional view of a part of the clutch in the second connected state.Figure 6 shows a cross-sectional view of the clutch when the clutch is in the third connected state.This is a flowchart of the process executed by the control unit shown in Figure 3, which switches the connection state in response to a braking request.This is a block diagram showing the power transmission path of a human-powered vehicle, including the drive unit for the modified human-powered vehicle. <Implementation> A drive unit 50 for a human-powered vehicle will be described with reference to Figures 1 to 11. A human-powered vehicle is a vehicle having at least one wheel and capable of being driven by at least human power. Human-powered vehicles include various types of bicycles, such as mountain bikes, road bikes, city bikes, cargo bikes, handbikes, and recumbent bikes. The number of wheels a human-powered vehicle may have is not limited. Human-powered vehicles also include, for example, unicycles and vehicles with two or more wheels. Human-powered vehicles are not limited to vehicles that can be driven solely by human power. Human-powered vehicles include e-bikes that utilize the driving force of an electric motor in addition to human power for propulsion. E-bikes include electric assist bicycles in which propulsion is assisted by an electric motor. Hereinafter, in each embodiment, the human-powered vehicle will be described as an electric assist bicycle. The human-powered vehicle 10 includes at least one wheel 12 and a body. The at least one wheel 12 includes a front wheel and a rear wheel 12R. The body includes a frame. The human-powered vehicle 10 further includes a crank into which human power is input. The crank includes a crankshaft 14 rotatable relative to the frame and a pair of crank arms. The first crank arm of the pair is provided at the first end of the axial end of the crankshaft 14, and the second crank arm of the pair is provided at the second end of the axial end of the crankshaft 14. A pedal is connected to each crank arm. The frame is connected to the front fork. The front wheel is mounted to the front fork. The handlebars are connected to the front fork via a stem. The rear wheel 12R is supported by the frame. In this embodiment, the crank is connected to the rear wheel 12R by a drive mechanism. The rear wheel 12R is driven by the rotation of the crankshaft 14. At least one of the front wheel and the rear wheel 12R may be connected to the crank by a drive mechanism. The drive mechanism includes a first drive mechanism rotating body connected to the crankshaft 14. In this embodiment, the first drive mechanism rotating body includes a front sprocket 16. The first drive mechanism rotating body may include a pulley or a bevel gear. The drive mechanism further includes a second drive mechanism rotating body and a connecting member. The connecting member is configured to transmit the rotational force of the first drive mechanism rotating body to the second drive mechanism rotating body. For example, the connecting member includes a chain 18. The connecting member may include a belt or a shaft. For example, the second drive mechanism rotating body includes a rear sprocket 20. The second drive mechanism rotating body may include a pulley or a bevel gear. For example, the chain 18 is wrapped around the front sprocket 16 and the rear sprocket 20. For example, the second drive mechanism rotating body is connected to the rear wheel 12R via the hub shell 22. The rear wheel 12R is configured to rotate in conjunction with the rotation of the second drive mechanism rotating body. Torque transmitted to the rear sprocket 20 is transmitted to the rear wheel 12R via the hub shell 22. A one-way clutch is not positioned between the rear sprocket 20 and the hub shell 22. For example, the rear sprocket 20 and the hub shell 22 are configured to rotate together in both directions of rotation of the whee