Drive unit

Abstract

To provide a drive unit that allows easy gear shifting.SOLUTION: The drive unit includes: an electric motor configured to apply propulsive force to a human-powered driving vehicle; an input rotary shaft to which human-powered driving power is inputted; an output rotary shaft to which the human-powered driving power is transmitted from the input rotary shaft, as well as to which motor-powered driving power is transmitted from the electric motor; a transmission mechanism provided on a transmission path of the human-powered driving power between the input rotary shaft and the output rotary shaft in a base portion, and configured to change a transmission ratio; and a control unit configured to control the electric motor. The transmission mechanism includes: an input portion connected to the input rotary shaft; and an output portion connected to the output rotation shaft. The electric motor is connected to the output portion of the transmission mechanism without passing through the input portion of the transmission mechanism. When the transmission ratio of the transmission mechanism is changed, the control unit controls the electric motor so as to increase the motor-powered driving power.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to the technology of drive units for human-powered vehicles. [Background technology]

[0002] Conventionally, drive units for human-powered vehicles have been known. For example, Patent Document 1 discloses a technology for a drive unit equipped with an electric motor and a transmission mechanism. The transmission mechanism includes multiple gears and a switching unit. The transmission mechanism changes the gear ratio by operating the switching unit in response to a user's operation to switch from among the multiple gears the gear that transmits the human-powered driving force. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2012 / 066124A1 publication Summary of the Invention [Problem to be solved by the invention]

[0004] In a conventional drive unit, when a transmission mechanism changes a gear ratio while human driving force is being input to a human-powered vehicle, it is difficult to change gears because a load is applied to the transmission mechanism.

[0005] An object of the present disclosure is to provide a drive unit that allows for easy gear shifting. [Means for solving the problem]

[0006] a control unit configured to control the electric motor, wherein the control unit controls the electric motor, when the transmission ratio of the transmission mechanism is changed, the control unit controls the electric motor, the control unit controls the electric motor, and the electric motor is connected to the input rotary shaft of the transmission mechanism, the control unit controls the electric motor, and the electric motor is connected to the input rotary shaft of the transmission mechanism, the control unit controls the electric motor, the control unit controls the electric motor, the control unit controls the electric motor, the control unit controls the electric motor, the control unit controls the electric motor, the control unit controls the electric motor, the control unit controls the electric motor, the control unit controls the electric motor, the control unit controls the electric motor, the control unit controls the electric motor, the drive unit is rotatably mounted on the base unit and a human-powered driving force is input, the input rotary shaft is rotatably mounted on the base unit and a human-powered driving force is input, the output rotary shaft is rotatably mounted on the base unit and a human-powered driving force is transmitted from the input rotary shaft and a motor driving force is transmitted from the electric motor, the drive unit is The human driving force when the gear ratio is changed Controlling the electric motor so that the motor driving force increases regardless of the situation the speed change mechanism includes an intermediate shaft that is provided on the base portion and can be rotated by the manual driving force from the input rotating shaft; a plurality of intermediate shaft input rotors that are selectively connectable to the intermediate shaft and connected to the input rotating shaft; a connection portion that is configured to selectively connect the plurality of intermediate shaft input rotors to the intermediate shaft so that the manual driving force is transmitted to the intermediate shaft; and at least one intermediate shaft output rotor that is provided on the intermediate shaft and connected to the output rotating shaft; the electric motor is connected to the intermediate shaft without passing through the plurality of intermediate shaft input rotors, and the control portion increases the motor driving force when changing the connection state between the plurality of intermediate shaft input rotors and the intermediate shaft by the connection portion. . According to the drive unit of the first aspect, when the gear ratio is changed, the motor driving force increases, which reduces the load on the gear change mechanism, making it easier to change gears. According to the drive unit of the first aspect, the rotation speed of the intermediate shaft can be increased by increasing the driving force of the motor, and the load on the connection portion can be reduced when changing the connection state between the intermediate shaft and the multiple intermediate shaft input rotors. According to the drive unit of the first aspect, the load on the connection portion can be reduced when changing the connection state between the intermediate shaft and the multiple intermediate shaft input rotors.

[0009] No. 1 Follow the side 2 In the side drive unit, the at least one intermediate shaft output rotor includes a plurality of intermediate shaft output rotors, which are selectively connectable to the intermediate shaft, and the connection portion is configured to selectively connect the plurality of intermediate shaft output rotors to the output rotor so that the manual driving force is transmitted to the output rotor. No. 2 The drive unit on the side increases the driving force of the motor, thereby increasing the rotational speed of the intermediate shaft and reducing the load on the connection portion when changing the connection state between the intermediate shaft and multiple intermediate shaft output rotors.

[0011] No.1 , or th 2 Follow the side 3 In the drive unit on the side, the control unit increases the motor driving force before changing the connection state between the intermediate shaft and the plurality of intermediate shaft input rotors by the connection unit. No. 3 The side drive unit can effectively reduce the load on the connection portion when changing the connection state between the intermediate shaft and the multiple intermediate shaft input rotors.

[0012] No. 1 , or th 2 Follow the side 4 In the drive unit on the side, the speed change mechanism is configured to rotate integrally with the output rotating shaft and includes one or more output shaft rotating bodies that are each connected to one or more intermediate shaft output rotating bodies, the electric motor is connected to any one of the one or more intermediate shaft output rotating bodies, and the one or more intermediate shaft output rotating bodies and the one or more output shaft rotating bodies form a reducer. No. 4 According to the drive unit on the side, the rotation speed of the motor can be reduced by the intermediate shaft output rotor and the output shaft rotor.

[0013] No. 1 Follow the side 5 In the side drive unit, the transmission mechanism includes a continuously variable transmission mechanism or a planetary gear mechanism. No. 5 The side drive unit can reduce the load on the continuously variable transmission or planetary gear mechanism.

[0014] First or second aspect Follow the 6 In the side drive unit, the input rotary shaft includes a crankshaft. No. 6 The side drive unit reduces the load on the transmission mechanism in a drive unit that includes a crankshaft. [Effects of the Invention]

[0015] The drive unit of the present disclosure makes it easy to change gears. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 2 is a side view showing the drive unit and the drive train according to the first embodiment. [Figure 2] FIG. 2 is a schematic diagram showing the configuration of a drive unit. [Figure 3] FIG. 10 is a side view showing a state in which the intermediate shaft and the intermediate shaft rotor are connected by a connecting portion. [Figure 4] FIG. 10 is a side view showing a state in which the intermediate shaft and the intermediate shaft rotor are not connected to each other. [Figure 5] FIG. 2 is a block diagram showing an example of a drive unit. [Figure 6] 4 is a flowchart showing a control flow in the first embodiment. [Figure 7] FIG. 3 is a schematic diagram showing how a manual driving force and a motor driving force are transmitted. [Figure 8] 10 is a flowchart showing a control flow in the second embodiment. [Figure 9] 10 is a flowchart showing a control flow in a third embodiment. [Figure 10] 10 is a flowchart showing a control flow in the fourth embodiment. [Figure 11] FIG. 11 is a schematic diagram showing the configuration of a drive unit according to a fifth embodiment. [Figure 12] FIG. 13 is a schematic diagram showing the configuration of a drive unit according to a sixth embodiment. [Figure 13] FIG. 13 is a schematic diagram showing the configuration of a drive unit according to a seventh embodiment. [Figure 14] FIG. 13 is a schematic diagram showing the configuration of a drive unit according to an eighth embodiment. [Figure 15] FIG. 13 is a schematic diagram showing the configuration of a drive unit according to a ninth embodiment. [Figure 16] FIG. 23 is a schematic diagram showing the configuration of a drive unit according to a tenth embodiment. [Figure 17]FIG. 22 is a cross-sectional view showing the configuration of a planetary gear mechanism according to an eleventh embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0017] (First embodiment) A drive unit 6 according to a first embodiment will be described. Fig. 1 to Fig. 7 are used to describe the drive unit 6 according to the first embodiment. Fig. 1 shows the drive unit 6 and a drive train 1. The drive unit 6 and the drive train 1 are provided in a human-powered vehicle.

[0018] A human-powered vehicle is a vehicle that has at least one wheel and can be propelled at least by human power. Human-powered vehicles include various types of bicycles, such as mountain bikes, road bikes, city bikes, cargo bikes, hand bikes, and recumbents. There is no limit to the number of wheels a human-powered vehicle has. Human-powered vehicles include, for example, unicycles and vehicles with two or more wheels. Human-powered vehicles are not limited to vehicles that can be propelled solely by human power. Human-powered vehicles include E-bikes that use not only human power but also the driving force of an electric motor 62 for propulsion. E-bikes include electrically assisted bicycles whose propulsion is assisted by an electric motor 62.

[0019] 1 is configured to transmit human-powered driving force to wheels. The drive train 1 includes a crank 2, a front sprocket 3, a drive chain 4, and a rear sprocket 5.

[0020] The crank 2 includes a crankshaft 2a that is rotatable relative to the frame of the human-powered vehicle, and a pair of crank arms 2b that are provided at both axial ends of the crankshaft 2a. Pedals 2c are connected to the pair of crank arms 2b, respectively.

[0021] The front sprocket 3 is connected to the rear sprocket 5 via a drive chain 4. The front sprocket 3 may be connected to the rear sprocket 5 via at least one of a belt and a shaft. The drive train 1 may include at least one of a pulley and a bevel gear instead of the sprocket.

[0022] The drive unit 6 is a drive unit 6 for a human-powered vehicle and comprises a base portion 10, an electric motor 62 mounted on the base portion 10 and configured to provide propulsion force to the human-powered vehicle, an input rotating shaft 20 rotatably mounted on the base portion 10 and to which human-powered driving force is input, an output rotating shaft 30 rotatably mounted on the base portion 10 and to which human-powered driving force is transmitted from the input rotating shaft 20 and to which motor driving force is transmitted from the electric motor 62, a speed change mechanism 40 mounted on the base portion 10 in the transmission path of the human-powered driving force between the input rotating shaft 20 and the output rotating shaft 30 and configured to change the gear ratio, and a control unit 72 configured to control the electric motor 62.

[0023] An example of a drive unit 6 is shown in Figures 1 to 5. The drive unit 6 includes a base portion 10, an input rotating shaft 20, an output rotating shaft 30, a speed change mechanism 40, a drive portion 60, and a control device 70. The base portion 10 shown in Figures 1 and 2 is formed hollow and forms a housing. The base portion 10 is provided on the frame of a human-powered vehicle. The base portion 10 rotatably supports a crankshaft 2a.

[0024] The input rotation shaft 20 is provided so as to penetrate the base portion 10. The input rotation shaft 20 has a central rotation axis. The central rotation axis of the input rotation shaft 20 is arranged coaxially with the central rotation axis of the crankshaft 2a. In this embodiment, the input rotation shaft 20 includes the crankshaft 2a. The input rotation shaft 20 may include a member different from the crankshaft 2a instead of the crankshaft 2a. The input rotation shaft 20 may be formed hollow or solid.

[0025] The output rotary shaft 30 is configured to rotate relative to the input rotary shaft 20. A front sprocket 3 is fixed to the output rotary shaft 30. The output rotary shaft 30 has a central rotation axis. The central rotation axis of the output rotary shaft 30 is arranged coaxially with the central rotation axis of the crankshaft 2a. The output rotary shaft 30 is formed hollow. The output rotary shaft 30 is arranged radially outside the input rotary shaft 20, and is arranged around the central rotation axis of the input rotary shaft 20 to surround the input rotary shaft 20. The input rotary shaft 20 is arranged to pass through the output rotary shaft 30.

[0026] The transmission mechanism 40 is provided on the base unit 10. The transmission mechanism 40 is disposed in the internal space of the base unit 10. The transmission mechanism 40 includes an input portion 41 connected to the input rotating shaft 20 and an output portion 44 connected to the output rotating shaft 30. In this embodiment, the transmission mechanism 40 is provided on the base unit 10 and includes an intermediate shaft 47 that is rotatable by manual driving force from the input rotating shaft 20, a plurality of intermediate shaft input rotors 50 that are selectively connectable to the intermediate shaft 47 and connected to the input rotating shaft 20, a connection portion 56 that is configured to selectively connect the plurality of intermediate shaft input rotors 50 to the intermediate shaft 47 so that the manual driving force is transmitted to the intermediate shaft 47, and a connection portion 56 that is provided on the intermediate shaft 47 and connected to the output rotating shaft 30. At least one and an intermediate shaft output rotor 53. At least one The intermediate shaft output rotor 53 includes a plurality of intermediate shaft output rotors 53. The plurality of intermediate shaft output rotors 53 are provided so as to be selectively connectable to the intermediate shaft 47.

[0027] Fig. 2 shows an example of the transmission mechanism 40. The transmission mechanism 40 shown in Fig. 2 includes an input portion 41, an output portion 44, an intermediate shaft 47, at least one intermediate shaft input rotor 50, at least one intermediate shaft output rotor 53, and a connection portion 56.

[0028] The input portion 41 includes at least one input shaft rotor 42. In this embodiment, the input portion 41 includes two input shaft rotors 42. The two input shaft rotors 42 are arranged side by side in the axial direction of the rotary input shaft 20. The two input shaft rotors 42 are configured to rotate integrally with the rotary input shaft 20. The two input shaft rotors 42 have central rotation axes that are coaxial with the central rotation axis of the rotary input shaft 20. Each input shaft rotor 42 is formed by an external gear. In this specification, of the two input shaft rotors 42, the input shaft rotor 42 that is arranged farther from the front sprocket 3 in the axial direction of the rotary input shaft 20 is referred to as a first input shaft rotor 42a. In this specification, of the two input shaft rotors 42, the input shaft rotor 42 that is arranged closer to the front sprocket 3 in the axial direction of the rotary input shaft 20 is referred to as a second input shaft rotor 42b. The diameter of the first input shaft rotor 42a is different from the diameter of the second input shaft rotor 42b, and the number of teeth of the first input shaft rotor 42a is different from the number of teeth of the second input shaft rotor 42b.

[0029] The output portion 44 includes at least one output shaft rotor 45. In this embodiment, the output portion 44 includes two output shaft rotors 45. The two output shaft rotors 45 are arranged side by side in the axial direction of the rotary output shaft 30. The two output shaft rotors 45 are configured to rotate integrally with the rotary output shaft 30. The two output shaft rotors 45 have central rotation axes that are coaxial with the central rotation axis of the rotary output shaft 30. Like the input shaft rotors 42, each output shaft rotor 45 is formed by an external gear. In this specification, of the two output shaft rotors 45, the output shaft rotor 45 that is arranged farther from the front sprocket 3 in the axial direction of the rotary input shaft 20 is referred to as a first output shaft rotor 45a. In this specification, of the two output shaft rotors 45, the output shaft rotor 45 that is arranged closer to the front sprocket 3 in the axial direction of the rotary input shaft 20 is referred to as a second output shaft rotor 45b. The diameter of the first output shaft rotor 45a is different from the diameter of the second output shaft rotor 45b, and the number of teeth of the first output shaft rotor 45a is different from the number of teeth of the second output shaft rotor 45b.

[0030] The intermediate shaft 47 is rotatably provided on the base portion 10. The intermediate shaft 47 is formed hollow. The intermediate shaft 47 has a central rotation axis. The central rotation axis of the intermediate shaft 47 is different from the central rotation axis of the crankshaft 2a. The intermediate shaft 47 is arranged so that the central rotation axis of the intermediate shaft 47 is parallel to the central rotation axis of the crankshaft 2a.

[0031] The number of the at least one intermediate shaft input rotor 50 is equal to the number of the at least one input shaft rotor 42. In this embodiment, the at least one intermediate shaft input rotor 50 includes two intermediate shaft input rotors 50. The two intermediate shaft input rotors 50 are arranged side by side in the axial direction of the intermediate shaft 47. Each intermediate shaft input rotor 50 has a rotational center axis that is coaxial with the rotational center axis of the intermediate shaft 47. In this specification, of the two intermediate shaft input rotors 50, the intermediate shaft input rotor 50 that is arranged farther from the front sprocket 3 in the axial direction of the input rotor shaft 20 is referred to as the first intermediate shaft input rotor 51. In this specification, of the two intermediate shaft input rotors 50, the intermediate shaft input rotor 50 that is arranged closer to the front sprocket 3 in the axial direction of the input rotor shaft 20 is referred to as the second intermediate shaft input rotor 52. The diameter of the first intermediate shaft input rotor 51 is different from the diameter of the second intermediate shaft input rotor 52. The number of teeth of the first intermediate shaft input rotor 51 and the number of teeth of the second intermediate shaft input rotor 52 are different.

[0032] As shown in Fig. 3, the first intermediate shaft input rotor 51 is formed by an external gear 51a. As shown in Fig. 3, the first intermediate shaft input rotor 51 includes a concave-convex portion 51b on the inner circumferential portion on the radially inner side with respect to the rotational axis of the first intermediate shaft input rotor 51. The concave-convex portion 51b is formed by alternately arranging concave and convex portions around the rotational axis of the first intermediate shaft input rotor 51. The external gear 51a forming the first intermediate shaft input rotor 51 is configured to mesh with the external gear forming the first input shaft rotor 42a.

[0033] 2 is formed by an external gear. The second intermediate shaft input rotor 52 includes an uneven portion similar to the uneven portion 51b of the first intermediate shaft input rotor 51 on an inner circumferential portion radially inward with respect to the rotational axis of the second intermediate shaft input rotor 52. The external gear forming the second intermediate shaft input rotor 52 is configured to mesh with the external gear forming the second input shaft rotor 42b.

[0034] The number of the at least one intermediate shaft output rotor 53 is equal to the number of the at least one output shaft rotor 45. In this embodiment, the at least one intermediate shaft output rotor 53 includes two intermediate shaft output rotors 53. The two intermediate shaft output rotors 53 are arranged side by side in the axial direction of the intermediate shaft 47. Each intermediate shaft output rotor 53 has a rotational center axis that is coaxial with the rotational center axis of the intermediate shaft 47. In this specification, of the two intermediate shaft output rotors 53, the intermediate shaft output rotor 53 that is arranged farther from the front sprocket 3 in the axial direction of the input rotating shaft 20 is referred to as a first intermediate shaft output rotor 54. In this specification, of the two intermediate shaft output rotors 53, the intermediate shaft output rotor 53 that is arranged closer to the front sprocket 3 in the axial direction of the input rotating shaft 20 is referred to as a second intermediate shaft output rotor 55. The diameter of the first intermediate shaft output rotor 54 is different from the diameter of the second intermediate shaft output rotor 55. The number of teeth of the first intermediate shaft output rotor 54 and the number of teeth of the second intermediate shaft output rotor 55 are different.

[0035] The first intermediate shaft output rotor 54 is formed by an external gear. The first intermediate shaft output rotor 54 includes an uneven portion similar to the uneven portion 51b of the first intermediate shaft input rotor 51 on an inner circumferential portion radially inward relative to the rotational axis of the first intermediate shaft output rotor 54. The external gear forming the first intermediate shaft output rotor 54 is configured to mesh with the external gear forming the first output shaft rotor 45a.

[0036] The second intermediate shaft output rotor 55 is formed by an external gear. The second intermediate shaft output rotor 55 includes an uneven portion similar to the uneven portion 51b of the first intermediate shaft input rotor 51 on an inner circumferential portion radially inward relative to the rotational axis of the second intermediate shaft output rotor 55. The external gear forming the second intermediate shaft output rotor 55 is configured to mesh with the external gear forming the second output shaft rotor 45b.

[0037] In this embodiment, when the rider depresses the pedals 2c to rotate the crankshaft 2a in a first direction, the manual driving force is transmitted from the crankshaft 2a to the front sprocket 3. The manual driving force is transmitted in the following order: the input rotating shaft 20, any one of the at least one input shaft rotating bodies 42, any one of the at least one intermediate shaft input rotating bodies 50, the intermediate shaft 47, any one of the at least one intermediate shaft output rotating bodies 53, any one of the at least one output shaft rotating bodies 45, the output rotating shaft 30, and the front sprocket 3.

[0038] The connecting portion 56 includes a first connecting portion 57 and a second connecting portion 58. The first connecting portion 57 is configured to selectively connect at least one intermediate shaft input rotor 50 to the intermediate shaft 47 so that the manual driving force is transmitted to the intermediate shaft 47. The first connecting portion 57 selectively connects at least one intermediate shaft input rotor 50 to the intermediate shaft 47. The connecting portion 56 is configured to selectively connect multiple intermediate shaft output rotors 53 to the output rotating shaft 30 so that the manual driving force is transmitted to the output rotating shaft 30. The second connecting portion 58 selectively connects the multiple intermediate shaft output rotors 53 to the output rotating shaft 30. FIG. 3 shows a state in which the first intermediate shaft input rotor 51 is connected to the intermediate shaft 47 by the first connecting portion 57. FIG. 4 shows a state in which the first intermediate shaft input rotor 51 is not connected to the intermediate shaft 47.

[0039] As shown in FIGS. 2 and 3 , the first connection portion 57 includes a first shift shaft 57a, at least one first claw portion 57b, and a first coupling portion 57c. The first shift shaft 57a is provided on the intermediate shaft 47. The first shift shaft 57a is disposed in the internal space of the intermediate shaft 47. The first shift shaft 57a has a rotational axis that is coaxial with the rotational axis of the intermediate shaft 47. At least one recess 57d is formed on the outer circumferential surface of the first shift shaft 57a. Each recess 57d is formed at a position on the first shift shaft 57a that overlaps with one of the intermediate shaft input rotors 50 in the radial direction of the intermediate shaft 47. In this embodiment, two recesses 57d are formed corresponding to one intermediate shaft input rotor 50. The two recesses 57d corresponding to one intermediate shaft input rotor 50 are disposed 180° apart in the circumferential direction about the rotational axis of the first shift shaft 57a.

[0040] In this embodiment, the two recesses 57d corresponding to one intermediate shaft input rotor 50 include two recesses 57d formed at a position overlapping with the first intermediate shaft input rotor 51 in the radial direction of the intermediate shaft 47, and two recesses 57d formed at a position overlapping with the second intermediate shaft input rotor 52. The phase of the two recesses 57d formed at the position overlapping with the first intermediate shaft input rotor 51 is different from the phase of the two recesses 57d formed at a position overlapping with the second intermediate shaft input rotor 52 in the circumferential direction of the intermediate shaft input rotor 50 relative to the rotational axis of the intermediate shaft input rotor 50.

[0041] The configuration of at least one first claw portion 57b will be described using Figure 3. The at least one first claw portion 57b is supported by the intermediate shaft 47. The at least one first claw portion 57b is provided in at least one recess 57d of the first shift shaft 57a. Each first claw portion 57b includes a base portion 57e and a tip portion 57f. The base portion 57e protrudes from the intermediate shaft 47 toward the first shift shaft 57a. The tip portion 57f protrudes from the intermediate shaft 47 toward the corresponding intermediate shaft input rotor 50. The tip portion 57f is biased toward the corresponding intermediate shaft input rotor 50 by a biasing portion such as a spring.

[0042] 3, portions of bases 57e of the pair of first claws 57b are positioned in recesses 57d of the first shift shaft 57a. In the state shown in FIG. 3, tip ends 57f of the pair of first claws 57b engage with concave-convex portions 51b of the first intermediate shaft input rotor 51. The engagement of tip ends 57f with concave-convex portions 51b connects the first intermediate shaft input rotor 51 to the intermediate shaft 47.

[0043] When the first intermediate shaft input rotor 51 shown in FIG. 3 rotates in a first rotational direction A1, the rotational force of the first intermediate shaft input rotor 51 is transmitted to the intermediate shaft 47 via the pair of first claws 57b, and the intermediate shaft 47 rotates integrally with the first intermediate shaft input rotor 51. The first rotational direction A1 includes the direction in which the first intermediate shaft input rotor 51 rotates when the crankshaft 2a rotates in the first direction. In this specification, for each of at least one intermediate shaft input rotor 50, a state in which the intermediate shaft input rotor 50 rotates integrally with the intermediate shaft 47 is described as a first state. In this specification, for each of at least one intermediate shaft output rotor 53, a state in which the intermediate shaft output rotor 53 rotates integrally with the intermediate shaft 47 is described as a first state.

[0044] For each of at least one intermediate shaft input rotor 50, it is sufficient that the intermediate shaft input rotor 50 and the intermediate shaft 47 are able to rotate integrally in the first rotational direction A1 in the first state. In this embodiment, for each of at least one intermediate shaft input rotor 50, even if the intermediate shaft input rotor 50 is rotated in a second rotational direction different from the first rotational direction A1 in the first state, the rotational force of the intermediate shaft input rotor 50 is not transmitted to the intermediate shaft 47 via the pair of first pawls 57b. The at least one intermediate shaft input rotor 50, the at least one first pawl 57b, and the intermediate shaft 47 form a one-way clutch that allows rotation of the intermediate shaft 47 relative to the at least one intermediate shaft input rotor 50 in the first rotational direction A1 and restricts rotation of the intermediate shaft 47 relative to the at least one intermediate shaft input rotor 50 in the second rotational direction.

[0045] 3 to the state shown in FIG. 4 , the first shift shaft 57a rotates relative to the intermediate shaft 47 in a second rotational direction opposite to the first rotational direction A1, and the base 57e of each first claw 57b is pressed by the first shift shaft 57a toward the first intermediate shaft input rotor 51. As the base 57e is pressed, the tip 57f of each first claw 57b is moved away from the first intermediate shaft input rotor 51 against the biasing force of the biasing portions, and the engagement between the tip 57f and the uneven portion 51b of the first intermediate shaft input rotor 51 is released. When the engagement between the tip 57f and the uneven portion 51b is released, the first intermediate shaft input rotor 51 and the intermediate shaft 47 are no longer connected to each other.

[0046] Because the phase of the two recesses 57d formed at a position overlapping with the first intermediate shaft input rotor 51 differs from the phase of the two recesses 57d formed at a position overlapping with the second intermediate shaft input rotor 52, the timing at which the pair of first claw portions 57b engage with the first intermediate shaft input rotor 51 differs from the timing at which the pair of first claw portions 57b engage with the second intermediate shaft input rotor 52. The timing at which the engagement between the pair of first claw portions 57b and the first intermediate shaft input rotor 51 is released and the timing at which the engagement between the pair of first claw portions 57b and the second intermediate shaft input rotor 52 is released are also different from each other.

[0047] 4, even if the first intermediate shaft input rotor 51 rotates in the first rotation direction A1, the rotational force of the first intermediate shaft input rotor 51 is not transmitted to the intermediate shaft 47, and the first intermediate shaft input rotor 51 rotates idly relative to the intermediate shaft 47. In this specification, the state in which the intermediate shaft input rotor 50 rotates idly relative to the intermediate shaft 47 for each of at least one intermediate shaft input rotor 50 is described as the second state. In this specification, the state in which the intermediate shaft output rotor 53 rotates idly relative to the intermediate shaft 47 for each of at least one intermediate shaft output rotor 53 is described as the second state.

[0048] 2 includes a second shift shaft 58a, at least one second claw 58b, and a second coupling portion 58c. The second shift shaft 58a is configured similarly to the first shift shaft 57a of the first connection portion 57. The at least one second claw 58b is configured similarly to the at least one first claw 57b. The at least one intermediate shaft output rotor 53, the at least one second claw 58b, and the intermediate shaft 47 form a one-way clutch that allows rotation of the intermediate shaft 47 relative to the at least one intermediate shaft output rotor 53 in the first rotational direction A1 and restricts rotation of the intermediate shaft 47 relative to the at least one intermediate shaft output rotor 53 in the second rotational direction.

[0049] The first connecting portion 57c is connected to the second connecting portion 58c of the second connecting portion 58. The first connecting portion 57c is configured to switch its transmission state between a first transmission state in which the rotational force of the first shift shaft 57a is transmitted to the second connecting portion 58c and a second transmission state in which the rotational force of the first shift shaft 57a is not transmitted to the second connecting portion 58c, depending on the relative angle between the first shift shaft 57a and the second shift shaft 58a about their respective rotational axes.

[0050] The first connecting portion 57c is provided on the end of the first shift shaft 57a that faces the second shift shaft 58a. The first shift shaft 57a is disposed coaxially with the second shift shaft 58a. The second connecting portion 58 is provided on the end of the second shift shaft 58a that faces the first shift shaft 57a. In the first transmission state, the first shift shaft 57a and the second shift shaft 58a are rotatable integrally with each other. In the second transmission state, the second shift shaft 58a does not rotate integrally with the first shift shaft 57a. The first connecting portion 57c and the second connecting portion 58c may be omitted, and the first shift shaft 57a and the second shift shaft 58a may be configured as an integral unit.

[0051] In this embodiment, when one of the two input shaft rotors 42 is in the second state and the other of the two input shaft rotors 42 is in the first state, the first connecting portion 57 switches one of the two input shaft rotors 42 from the second state to the first state and sets the other of the two input shaft rotors 42 to the second state, thereby changing the speed change ratio of the transmission mechanism 40. In this specification, the speed change ratio defined by one of the at least one input shaft rotors 42 and one of the at least one intermediate shaft input rotors 50 is referred to as the input-side speed change ratio. The input-side speed change ratio is determined by the number of teeth of the at least one intermediate shaft input rotor 50 that is in the first state and the number of teeth of the at least one input shaft rotor 42 that meshes with the intermediate shaft input rotor 50 that is in the first state. The speed change ratio on the input side differs between when the first intermediate shaft input rotator 51 is in the first state and when the second intermediate shaft input rotator 52 is in the first state.

[0052] 2 is configured to selectively connect two intermediate shaft output rotors 53 to the intermediate shaft 47. In this embodiment, when one of the two intermediate shaft output rotors 53 is in the second state and the other of the two intermediate shaft output rotors 53 is in the first state, the second connection part 58 switches one of the intermediate shaft output rotors 53 from the second state to the first state and switches the other intermediate shaft output rotor 53 from the first state to the second state, thereby changing the speed change ratio of the transmission mechanism 40. In this specification, the speed change ratio defined by one of the at least one output shaft rotors 45 and one of the at least one intermediate shaft output rotors 53 is referred to as the output-side speed change ratio. The output side transmission ratio is determined by the number of teeth of the at least one intermediate shaft output rotor 53 that is in the first state, and the number of teeth of the output shaft rotor 45 that meshes with the at least one intermediate shaft output rotor 53 that is in the first state, among the at least one intermediate shaft output rotor 53. The output side transmission ratio differs when the first intermediate shaft output rotor 54 is in the first state and when the second intermediate shaft output rotor 55 is in the first state.

[0053] The drive unit 60 shown in Fig. 5 includes an actuator 61 and an electric motor 62. The actuator 61 is configured to drive the first shift shaft 57a, thereby rotating the first shift shaft 57a shown in Fig. 2 relative to the intermediate shaft 47. The actuator 61 is configured to drive the first shift shaft 57a, thereby driving the second shift shaft 58a.

[0054] In this embodiment, the transmission mechanism 40 is configured so that the actuator 61 can switch between a plurality of shift stages with different gear ratios of the transmission mechanism 40. The actuator 61 includes, for example, an electric motor. In this embodiment, the gear ratio of the transmission mechanism 40 is determined by an input-side gear ratio and an output-side gear ratio. The plurality of shift stages includes a first shift stage, a second shift stage having a higher gear ratio than the first shift stage, a third shift stage having a higher gear ratio than the second shift stage, and a fourth shift stage having a higher gear ratio than the third shift stage.

[0055] In the first speed change stage, the first connecting portion 57 sets the first intermediate shaft input rotator 51 in the second state and the second intermediate shaft input rotator 52 in the first state so as to achieve the lowest speed change ratio among the multiple input side speed change ratios. In the first speed change stage, the second connecting portion 58 sets the second intermediate shaft output rotator 55 in the first state and the first intermediate shaft output rotator 54 in the second state so as to achieve the lowest speed change ratio among the multiple output side speed change ratios.

[0056] When the transmission stage switches from the first transmission stage to the second transmission stage, the first connection portion 57 switches the connection state between the intermediate shaft 47 and at least one intermediate shaft input rotor 50 so that the input side transmission ratio becomes higher than the input side transmission ratio in the first transmission stage. When the transmission stage switches from the first transmission stage to the second transmission stage, the second connection portion 58 does not change the connection state between the intermediate shaft 47 and at least one intermediate shaft output rotor 53.

[0057] When the shift stage switches from the second shift stage to the third shift stage, the first connection portion 57 switches the connection state between the intermediate shaft 47 and at least one intermediate shaft input rotor 50 so that the input side gear ratio is lower than the input side gear ratio in the second shift stage. When the shift stage switches from the second shift stage to the third shift stage, the second connection portion 58 switches the connection state between the intermediate shaft 47 and at least one intermediate shaft output rotor 53 so that the output side gear ratio is higher than the output side gear ratio in the second shift stage. When switching from the second shift stage to the third shift stage, the actuator 61 connects the first coupling portion 57c to the second coupling portion 58c. By connecting the first coupling portion 57c and the second coupling portion 58c, the rotational force of the first shift shaft 57a is transmitted to the second shift shaft 58a, and the connection state of the second coupling portion 58 is switched.

[0058] When the speed change stage switches from the third speed change stage to the fourth speed change stage, the first connection portion 57 switches the connection state between the intermediate shaft 47 and at least one intermediate shaft input rotor 50 so that the input side speed change ratio becomes higher than the input side speed change ratio in the third speed change stage. The second connection portion 58 does not change the connection state between the intermediate shaft 47 and at least one intermediate shaft output rotor 53.

[0059] The number of transmission stages is not limited to that of the present embodiment. The number of transmission stages may be increased by adding gear pairs to the transmission mechanism 40 shown in FIG. 2. In the present embodiment, for example, if at least one input shaft rotating body 42 and at least one intermediate shaft input rotating body 50 include three gear pairs, the number of transmission stages increases from four to six. The number of transmission stages may also be reduced by removing gear pairs from the transmission mechanism 40 shown in FIG. 2. The number of transmission stages is set, for example, in the range of three to twenty-four stages.

[0060] The electric motor 62 shown in FIGS. 2 and 5 is configured to provide propulsive force to the human-powered vehicle. The electric motor 62 is provided on the base 10. For example, the electric motor 62 is provided in the internal space of a housing formed by the base 10. The electric motor 62 is connected to the output portion 44 of the transmission mechanism 40 without passing through the input portion 41 of the transmission mechanism 40. In this embodiment, the electric motor 62 is connected to the intermediate shaft 47 without passing through the multiple intermediate shaft input rotors 50. The electric motor 62 includes a first connection gear 62a fixed to the rotary shaft of the electric motor 62 and a second connection gear 62b meshing with the first connection gear 62a. The second connection gear 62b meshes with the second intermediate shaft output rotor 55. The motor driving force of the electric motor 62 is transmitted to the first connecting gear 62a, the second connecting gear 62b, the second intermediate shaft output rotor 55, the second output shaft rotor 45b, the output rotor shaft 30, and the front sprocket 3 in this order.

[0061] In this embodiment, a one-way clutch formed by at least one second intermediate shaft output rotor 55, at least one second claw portion 58b, and intermediate shaft 47 is disposed in the motor driving force transmission path from electric motor 62 to front sprocket 3. Unlike this embodiment, if a one-way clutch formed by at least one intermediate shaft output rotor 53, at least one second claw portion 58b, and intermediate shaft 47 is not disposed in the motor driving force transmission path from electric motor 62 to front sprocket 3, a separate one-way clutch will be disposed in the motor driving force transmission path. The one-way clutch may be any of a roller clutch, a claw clutch, and a sprag clutch.

[0062] 5 includes a storage unit 71 and a control unit 72. The storage unit 71 stores a control program and information used in the control process. The storage unit 71 includes, for example, at least one of a non-volatile memory, a volatile memory, and a hard disk.

[0063] The control unit 72 is configured to execute control related to the drive unit 6. The control unit 72 includes an arithmetic processing unit that executes a predetermined control program. The arithmetic processing unit includes, for example, a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). The control unit 72 At least one It may also include a microcomputer.

[0064] The control unit 72 is configured to drive the actuator 61 in accordance with the operating state of the gearshift operating unit 80. The gearshift operating unit 80 is provided, for example, on the handlebar of a human-powered vehicle. The gearshift operating unit 80 is configured to be operated by a user with their hands or fingers. The gearshift operating unit 80 includes at least one of a lever and a button. The operating states of the gearshift operating unit 80 include an operating state related to upshifting and an operating state related to downshifting. The operating state related to upshifting includes, for example, a state in which the lever is swung in a predetermined first operating direction. The operating state related to downshifting includes, for example, a state in which the lever is swung in a second operating direction different from the first operating direction. The gearshift operating unit 80 includes an operating state detection unit 81 configured to detect the operating state. The operating state detection unit 81 detects the operating state based, for example, on the amount of movement of the lever.

[0065] The control unit 72 is configured to be able to communicate with the operation state detection unit 81 via an electric cable or a wireless communication device. A signal corresponding to the operation state is input to the control unit 72 from the operation state detection unit 81. When the control unit 72 detects an operation state related to an upshift based on the signal from the operation state detection unit 81, the control unit 72 drives the actuator 61 so as to increase the gear ratio of the transmission mechanism 40. For example, when the current gear stage is the second gear stage, the control unit 72 drives the actuator 61 so as to switch from the second gear stage to the third gear stage when it detects an operation state related to an upshift based on the signal from the gear shift operation unit 80.

[0066] The control unit 72 controls the electric motor 62 to provide a propulsive force to the human-powered vehicle in accordance with predetermined parameters. In this specification, the ratio of the motor driving force to the human-powered driving force is referred to as the assist ratio. In this embodiment, the predetermined parameters include multiple assist modes and the human-powered driving force input to the human-powered vehicle. The multiple assist modes differ in at least one of the maximum assist ratio of the motor driving force of the electric motor 62 to the human-powered driving force and the upper limit of the traveling speed of the human-powered vehicle at which the electric motor 62 continues to be driven in response to the input human-powered driving force. The human-powered vehicle is configured so that one of the multiple assist modes can be selected by the rider operating a predetermined operating device. The memory unit 71 stores the current assist mode selected by the rider.

[0067] The control unit 72 is configured to detect the manual driving force. In this embodiment, the control unit 72 is configured to detect the manual driving force based on a signal from the manual driving force detection unit 84. The manual driving force detection unit 84 is provided, for example, in the driving force transmission path from the pedal 2c to the front sprocket 3. The manual driving force detection unit 84 includes at least one of a strain sensor, a magnetostrictive sensor, an optical sensor, and a pressure sensor. The manual driving force detection unit 84 is configured to be able to communicate with the control unit 72 via an electric cable or a wireless communication device. The manual driving force detection unit 84 outputs a signal corresponding to the manual driving force applied to the pedal 2c to the control unit 72.

[0068] When the control unit 72 detects the manual driving force based on a signal from the manual driving force detection unit 84, it controls the electric motor 62 so that the ratio of the motor driving force to the manual driving force does not exceed the maximum assist ratio in the current assist mode. In this embodiment, when the control unit 72 controls the electric motor 62, the control unit 72 calculates the motor driving force in accordance with the manual driving force, etc., and therefore the motor driving force depends on the manual driving force.

[0069] In this embodiment, when the gear ratio of the transmission mechanism 40 is changed, the control unit 72 controls the electric motor 62 so as to increase the motor driving force. An example of the control performed by the control unit 72 will be described below. FIG. 6 is used to describe the example of the control performed by the control unit 72. The control unit 72 starts a first control flow according to the flowchart shown in FIG. 6 when a predetermined condition is satisfied. In this embodiment, the control unit 72 starts the first control flow when power starts to be supplied to the drive unit 6 from a predetermined power source. After the first control flow ends, the control unit 72 repeatedly executes the first control flow at predetermined time intervals until the predetermined condition is satisfied. In this embodiment, the control unit 72 repeatedly executes the first control flow until power is no longer supplied to the drive unit 6 from the predetermined power source.

[0070] In step S1, the control unit 72 detects that the gear ratio of the transmission mechanism 40 will be changed. The control unit 72 detects that the gear ratio will be changed, for example, by detecting at least one of an operation state related to an upshift and an operation state related to a downshift based on a signal from the operation state detection unit 81. The control unit 72 may also detect that the gear ratio of the transmission mechanism 40 will be changed based on information other than the operation state of the gear shift operation unit 80. If the gear ratio of the transmission mechanism 40 will be changed, the control unit 72 proceeds to step S2. If the gear ratio of the transmission mechanism 40 will not be changed, the control unit 72 ends the first control flow.

[0071] In step S2, the control unit 72 controls the electric motor 62 to increase the motor driving force. In step S2, the control unit 72 increases the motor driving force even if the manual driving force does not increase. In step S2, the control unit 72 may add a predetermined driving force to the motor driving force calculated according to the assist mode. In step S2, the control unit 72 may increase the assist ratio. By executing step S2, the control unit 72 may increase the motor driving force corresponding to the manual driving force even if the manual driving force decreases. Unlike this embodiment, the control unit 72 can handle cases where the motor driving force depends on the rotational speed of the input rotation shaft 20 in the same way as when the motor driving force depends on the manual driving force. After performing the processing of step S2, the control unit 72 proceeds to step S2-1.

[0072] In step S2-1, the control unit 72 determines whether a predetermined condition is satisfied. For example, the control unit 72 determines that the predetermined condition is satisfied when a predetermined time has elapsed since performing the process of step S2. The predetermined time is, for example, a time in the range of 0.5 seconds or more and 5 seconds or less. For example, the control unit 72 may determine that the predetermined condition is satisfied when a gear shift is completed. The control unit 72 repeatedly executes step S2-1 until it determines that the predetermined condition is satisfied. If the control unit 72 determines that the predetermined condition is satisfied in step S2-1, it proceeds to step 2-2.

[0073] In step S2-2, the control unit 72 controls the electric motor 62 to reduce the motor driving force increased in step S2, and then ends the first control flow. In step S2-2, the control unit 72 reduces the motor driving force by, for example, the amount of motor driving force increased in step S2. In step S2-2, the control unit 72 may reduce the motor driving force by, for example, an amount of motor driving force different from the amount of motor driving force increased in step S2.

[0074] By executing the first control flow by the control unit 72, the load on the transmission mechanism 40 can be reduced, making it easier for the transmission mechanism 40 to change the gear ratio of the transmission mechanism 40. The load on the transmission mechanism 40 will be described with reference to Figures 2 and 3.

[0075] When a human-powered driving force is input to a human-powered vehicle, the human-powered driving force is transmitted to the first intermediate shaft input rotor 51 shown in FIG. 3 via the input rotating shaft 20 shown in FIG. 2 and the first input shaft rotor 42a. The transmission of the human-powered driving force causes the first intermediate shaft input rotor 51 to rotate in a first rotation direction A1 about the rotational axis of the first intermediate shaft input rotor 51. As the first intermediate shaft input rotor 51 rotates, the uneven portion 51b of the first intermediate shaft input rotor 51 presses the tip ends 57f of the pair of first claws 57b, applying a load to the pair of first claws 57b. The intermediate shaft 47 rotates in the same direction as the first intermediate shaft input rotor 51 due to the pressing of the tip ends 57f of the pair of first claws 57b.

[0076] 3, when the gear ratio of the transmission mechanism 40 is changed, the tip ends 57f of the pair of first claws 57b are moved away from the first intermediate shaft input rotor 51 by the rotation of the first shift shaft 57a. When human-powered driving force is input to the human-powered vehicle while changing the gear ratio of the transmission mechanism 40, the tip ends 57f of the pair of first claws 57b are pressed by the uneven portion 51b, and as the tip ends 57f of the pair of first claws 57b move, a frictional force is generated between the first intermediate shaft input rotor 51 and the pair of first claws 57b. When the frictional force increases, it becomes more difficult for the tip ends 57f to come off the first intermediate shaft input rotor 51, thereby increasing the resistance to gear shifting.

[0077] The control unit 72 increases the motor driving force when the speed change ratio of the speed change mechanism 40 is changed by executing the first control flow. For example, when the second relay shaft output rotor 55 shown in FIG. 7 is in the first state and the first relay shaft output rotor 54 is in the second state, the increased motor driving force causes the motor driving force to be transmitted to the relay shaft 47 via the first connecting gear 62a, the second connecting gear 62b, and the second relay shaft output rotor 55. When the first relay shaft output rotor 54 is in the first state and the second relay shaft output rotor 55 is in the second state, the motor driving force is transmitted to the relay shaft 47 via the first connecting gear 62a, the second connecting gear 62b, the second relay shaft output rotor 55, the second output shaft rotor 45b, the output rotor shaft 30, the first output shaft rotor 45a, and the first relay shaft output rotor 54.

[0078] When the motor driving force is transmitted to the intermediate shaft 47, the relative rotational speed of the intermediate shaft 47 with respect to the first intermediate shaft input rotor 51 increases. As the rotational speed increases, the force with which the tip ends 57f of the pair of first claws 57b are pressed by the uneven portions 51b of the first intermediate shaft input rotor 51 decreases, thereby reducing the frictional force between the first intermediate shaft input rotor 51 and the pair of first claws 57b. When the frictional force decreases, the load on the transmission mechanism 40 is reduced, and the tip ends 57f of the pair of first claws 57b can more easily come out of the uneven portions 51b of the first intermediate shaft input rotor 51. Because the transmission mechanism 40 can rotate the first shift shaft 57a in a state in which the tip ends 57f can more easily come out of the uneven portions 51b, the transmission ratio of the transmission mechanism 40 can be more easily changed.

[0079] Even if the rotation speed of the intermediate shaft 47 due to the manual driving force and the rotation speed due to the electric motor 62 are the same, the torque applied to the intermediate shaft 47 by the manual driving force decreases, and the resistance to speed change decreases.

[0080] The control unit 72 may change the magnitude of the increase in the motor driving force in step S2 depending on the speed change stage. When the connection state of at least one intermediate shaft output rotor 53 is changed, the control unit 72 may increase the motor driving force by a larger amount than when the state of at least one intermediate shaft output rotor 53 is not changed.

[0081] (Second embodiment) A drive unit 6 of the second embodiment will be described. The drive unit 6 of the second embodiment will be described using Figures 3, 6, and 8. The same reference numerals as in the first embodiment are used for the components common to the first embodiment, and redundant description will be omitted.

[0082] In this embodiment, when the manual driving force is smaller than a predetermined manual driving force and when the gear ratio of the transmission mechanism 40 is changed, the control unit 72 controls the electric motor 62 so as not to increase the motor driving force. An example of the control performed by the control unit 72 will be described below. FIG. 8 is used to explain the example of the control performed by the control unit 72. The control unit 72 starts a second control flow according to the flowchart shown in FIG. 8 when a predetermined condition is satisfied. When the second control flow ends, the control unit 72 repeatedly executes the second control flow at predetermined time intervals until the predetermined condition is satisfied. The conditions for starting the second control flow and the conditions for repeating the execution of the second control flow are the same as those for the first control flow in the first embodiment.

[0083] In step S11, if the speed change ratio of the transmission mechanism 40 is to be changed, the control unit 72 proceeds to step S12. If the speed change ratio of the transmission mechanism 40 is not to be changed, the control unit 72 ends the second control flow.

[0084] In step S12, the control unit 72 detects the manual driving force based on a signal from the manual driving force detection unit 84. The control unit 72 obtains a predetermined manual driving force by reading information stored in the memory unit 71. The predetermined driving force is set to 5 Nm, for example. The predetermined driving force is not limited to 5 Nm. If the manual driving force is smaller than the predetermined manual driving force, the control unit 72 proceeds to step S13. If the manual driving force is equal to or greater than the predetermined manual driving force, the control unit 72 proceeds to step S14.

[0085] In step S13, the control unit 72 controls the electric motor 62 so as to increase the motor driving force by the same process as in step S2 shown in Fig. 6. After performing the process of step S13, the control unit 72 proceeds to step S13-1.

[0086] In step S13-1, the control unit 72 determines whether a predetermined condition is satisfied. The predetermined condition is, for example, the same as the predetermined condition in step S2-1 shown in FIG. 6. The predetermined condition may be different from the predetermined condition in step S2-1 shown in FIG. 6. The control unit 72 repeatedly executes step S13-1 until it determines that the predetermined condition is satisfied. If the control unit 72 determines that the predetermined condition is satisfied in step S13-1, it proceeds to step S13-2.

[0087] In step S13-2, the control unit 72 controls the electric motor 62 so as to reduce the motor driving force that was increased in step S13-1, similar to step S2-2 shown in FIG. 6, and then ends the second control flow.

[0088] In step S14, the control unit 72 controls the electric motor 62 so as not to increase the motor driving force. After performing the process of step S14, the control unit 72 ends the second control flow. In step S14, the control unit 72 may control the electric motor 62 so as not to increase the motor driving force even when the manual driving force increases, or may control the electric motor 62 so as not to increase the motor driving force by not performing the process of step S13.

[0089] When the manual driving force is smaller than a predetermined manual driving force, the load on the transmission mechanism 40 is small, and therefore the frictional force between the first intermediate shaft input rotor 51 and the pair of first claws 57b that occurs when the tip ends 57f of the pair of first claws 57b shown in FIG. 3 move is relatively small. By executing the second control flow, the control unit 72 does not increase the motor driving force when the load on the transmission mechanism 40 is small, and performs assist mode and normal control that controls the electric motor 62 in accordance with the manual driving force. The control by the control unit 72 makes it possible to avoid difficulty in shifting gears and reduce power consumption.

[0090] (Third embodiment) A drive unit 6 of the third embodiment will be described. Figures 6 and 9 will be used to describe the drive unit 6 of the third embodiment. Configurations common to the first and second embodiments are given the same reference numerals as the first and second embodiments, and duplicated descriptions will be omitted.

[0091] In this embodiment, the control unit 72 increases the motor driving force when the connection state between the multiple intermediate shaft input rotors 50 and the intermediate shaft 47 is changed by the connection unit 56. An example of control executed by the control unit 72 will be described. FIG. 9 is used to explain the example of control executed by the control unit 72. The control unit 72 starts a third control flow according to the flowchart shown in FIG. 9 when a predetermined condition is satisfied. When the third control flow ends, the control unit 72 repeatedly executes the third control flow at predetermined time intervals until the predetermined condition is satisfied. The conditions for starting the third control flow and the conditions for repeating the execution of the third control flow are the same as those for the first control flow in the first embodiment.

[0092] In step S21, the control unit 72 detects that the connection state between at least one intermediate shaft input rotator 50 and the intermediate shaft 47 will be changed. In this embodiment, regardless of the current speed change stage, when the speed change stage is changed, the connection state between at least one intermediate shaft input rotator 50 and the intermediate shaft 47 will be changed. The control unit 72 detects that the connection state between the intermediate shaft input rotator 50 and the intermediate shaft 47 will be changed, for example, by detecting that the speed change stage will be changed based on the operating state of the speed change operating unit 80.

[0093] Unlike the present embodiment, if the connection state between at least one intermediate shaft input rotator 50 and the intermediate shaft 47 changes only in a change of some of the gear shift stages, the control unit 72 acquires the current gear shift stage by reading information stored in the memory unit 71. The control unit 72 detects that the connection state between at least one intermediate shaft input rotator 50 and the intermediate shaft 47 will change in a change of the gear ratio of the transmission mechanism 40 based on the current gear shift stage, the operation state related to upshifting, and the operation state related to downshifting. If the connection state between at least one intermediate shaft input rotator 50 and the intermediate shaft 47 changes, the control unit 72 proceeds to step S22. If the connection state between at least one intermediate shaft input rotator 50 and the intermediate shaft 47 does not change, the control unit 72 ends the third control flow.

[0094] In step S22, the control unit 72 controls the electric motor 62 to increase the motor driving force by processing similar to that of step S2 shown in Fig. 6. For example, the control unit 72 increases the motor driving force at the same timing as when the control unit 72 drives the actuator 61 to change the connection state between at least one intermediate shaft input rotor 50 and the intermediate shaft 47. After performing the processing of step S22, the control unit 72 proceeds to step S22-1.

[0095] In step S22-1, the control unit 72 determines whether a predetermined condition is satisfied. The predetermined condition is, for example, the same as the predetermined condition in step S2-1 shown in FIG. 6. The predetermined condition may be different from the predetermined condition in step S2-1 shown in FIG. 6. The control unit 72 repeatedly executes step S22-1 until it determines that the predetermined condition is satisfied. If the control unit 72 determines in step S22-1 that the predetermined condition is satisfied, the control unit 72 proceeds to step S22-2.

[0096] In step S22-2, similar to step S2-2 shown in FIG. 6, the control unit 72 controls the electric motor 62 so that the motor driving force that was increased in step S22-1 is reduced, and then the third control flow ends.

[0097] The control unit 72 executes the third control flow, and thereby increases the motor driving force when the connection state between at least one intermediate shaft input rotator 50 and the intermediate shaft 47 is changed. Increasing the motor driving force makes it easier for the tip ends 57f of the pair of first claws 57b to come out of the at least one intermediate shaft input rotator 50, making it easier for the transmission mechanism 40 to change the gear ratio.

[0098] (Fourth embodiment) A drive unit 6 of the fourth embodiment will be described. The drive unit 6 of the fourth embodiment will be described using Figures 6 and 10. The same reference numerals as in the first to third embodiments are used for the configurations common to the first to third embodiments, and redundant description will be omitted.

[0099] In this embodiment, the control unit 72 increases the motor driving force before changing the connection state between the multiple intermediate shaft input rotors 50 and the intermediate shaft 47 by the connection unit 56. An example of control executed by the control unit 72 will be described. FIG. 10 is used to explain the example of control executed by the control unit 72. The control unit 72 starts a fourth control flow according to the flowchart shown in FIG. 10 when a predetermined condition is satisfied. After the fourth control flow ends, the control unit 72 repeatedly executes the fourth control flow at predetermined time intervals until the predetermined condition is satisfied. The conditions for starting the fourth control flow and the conditions for repeating the execution of the fourth control flow are the same as those for the first control flow in the first embodiment.

[0100] In step S31, if the speed change ratio of the transmission mechanism 40 is to be changed, the control unit 72 proceeds to step S32. If the speed change ratio of the transmission mechanism 40 is not to be changed, the control unit 72 ends the fourth control flow.

[0101] In step S32, the control unit 72 controls the electric motor 62 so that the motor driving force increases before changing the connection state between at least one intermediate shaft input rotor 50 and the intermediate shaft 47. After performing the process of step S32, the control unit 72 proceeds to step S32-1.

[0102] In step S32-1, the control unit 72 determines whether a predetermined condition is satisfied. The predetermined condition is, for example, the same as the predetermined condition in step S2-1 shown in FIG. 6. The predetermined condition may be different from the predetermined condition in step S2-1 shown in FIG. 6. The control unit 72 repeatedly executes step S32-1 until it determines that the predetermined condition is satisfied. If the control unit 72 determines in step S32-1 that the predetermined condition is satisfied, the control unit 72 proceeds to step S32-2.

[0103] 6, in step S32-2, the control unit 72 controls the electric motor 62 to reduce the motor driving force that was increased in step S23-1, and then ends the fourth control flow. After ending the fourth control flow, the control unit 72 drives the actuator 61 to change the connection state between at least one intermediate shaft input rotor 50 and the intermediate shaft 47.

[0104] By executing the fourth control flow, the control unit 72 can change the gear ratio of the transmission mechanism 40 after the motor driving force is transmitted to the intermediate shaft 47 and the pair of first claws 57b and the pair of second claws 58b become easily disengaged from the at least one intermediate shaft input rotor 50 and the at least one intermediate shaft output rotor 53. Control according to the fourth control flow can effectively reduce the load on the transmission mechanism 40.

[0105] (Fifth embodiment) A drive unit 6 of the fifth embodiment will be described. The drive unit 6 of the fifth embodiment will be described using Figures 6 and 8 to 11. The same reference numerals as in the first to fourth embodiments will be used for the components common to the first to fourth embodiments, and redundant description will be omitted.

[0106] In this embodiment, the electric motor 62 of the drive unit 6 shown in FIG. 11 is directly connected to the intermediate shaft 47. The electric motor 62 is coupled to a fixed gear 62c fixed to the intermediate shaft 47, thereby being directly connected to the intermediate shaft 47. The fixed gear 62c is configured as an external gear. The output gear of the electric motor 62 meshes with the fixed gear 62c. The fixed gear 62c is provided between at least one intermediate shaft input rotor 50 and at least one intermediate shaft output rotor 53. The position of the fixed gear 62c is not limited to this embodiment; at least one intermediate shaft input rotor 50 may be disposed between the fixed gear 62c and at least one intermediate shaft output rotor 53, and at least one intermediate shaft output rotor 53 may be disposed between the fixed gear 62c and at least one intermediate shaft input rotor 50.

[0107] In this embodiment, the control unit 72 executes at least one of the first control flow shown in Fig. 6, the second control flow shown in Fig. 8, the third control flow shown in Fig. 9, and the fourth control flow shown in Fig. 10. Execution of the control flow makes it easier for the transmission mechanism 40 to change the gear ratio.

[0108] (Sixth embodiment) A drive unit 6 of the sixth embodiment will be described. Fig. 12 is used to describe the drive unit 6 of the sixth embodiment. The same reference numerals as those in the first to fifth embodiments are used for the components common to the first to fifth embodiments, and redundant description will be omitted.

[0109] In this embodiment, the electric motor 62 of the drive unit 6 is connected to one of the at least one output shaft rotor 45 via a connecting gear 62d. In this embodiment, the connecting gear 62d is connected to the second output shaft rotor 45b. The connecting gear 62d meshes with an external gear that constitutes the second output shaft rotor 45b. The connecting gear 62d may also be connected to the first output shaft rotor 45a instead of the second output shaft rotor 45b.

[0110] In this embodiment, the control unit 72 executes at least one of the first to fourth control flows, similar to the control unit 72 in the fifth embodiment. By executing the control flows, the transmission mechanism 40 can easily change the gear ratio.

[0111] (Seventh embodiment) A drive unit 6 of the seventh embodiment will be described. Fig. 13 is used to describe the drive unit 6 of the seventh embodiment. The same reference numerals as those in the first to sixth embodiments are used for the components common to the first to sixth embodiments, and redundant description will be omitted.

[0112] The electric motor 62 of the drive unit 6 is connected to one of the at least one intermediate shaft input rotor 50 via a connecting gear 62e. In this embodiment, the electric motor 62 of the drive unit 6 is connected to the first intermediate shaft input rotor 51 via the connecting gear 62e. The connecting gear 62e meshes with an external gear that constitutes the first intermediate shaft input rotor 51. The connecting gear 62e may be connected to the second intermediate shaft input rotor 52 instead of the first intermediate shaft input rotor 51.

[0113] In this embodiment, the control unit 72 executes at least one of the first to fourth control flows, similar to the control unit 72 in the fifth embodiment. By executing the control flows, the transmission mechanism 40 can easily change the gear ratio.

[0114] (Eighth embodiment) A drive unit 6 of the eighth embodiment will be described. Fig. 14 is used to describe the drive unit 6 of the eighth embodiment. The same reference numerals as those in the first to seventh embodiments are used for the components common to the first to seventh embodiments, and redundant description will be omitted.

[0115] In this embodiment, one intermediate shaft input rotor 43 is provided on the intermediate shaft 47. The intermediate shaft input rotor 43 is configured to rotate integrally with the intermediate shaft 47 when the crankshaft 2a rotates in the first direction. In this embodiment, the connecting portion 56 does not include the first connecting portion 57 or the first shift shaft 57a.

[0116] In this embodiment, the control unit 72 executes at least one of the first to fourth control flows, similar to the control unit 72 in the fifth embodiment. By executing the control flows, the transmission mechanism 40 can easily change the gear ratio.

[0117] (Ninth embodiment) A drive unit 6 of the ninth embodiment will be described. Fig. 15 is used to describe the drive unit 6 of the ninth embodiment. The same reference numerals as those in the first to eighth embodiments are used for the configurations common to the first to eighth embodiments, and redundant description will be omitted.

[0118] In this embodiment, one intermediate shaft output rotor 83 is provided on the intermediate shaft 47. The electric motor 62 is connected to the second intermediate shaft input rotor 52 via a first connecting gear 62a and a second connecting gear 62f. The intermediate shaft output rotor 83 is configured to rotate integrally with the intermediate shaft 47 when the crankshaft 2a rotates in the first direction. In this embodiment, the connection portion 56 does not include the second connection portion 58 or the second shift shaft 58a.

[0119] In this embodiment, the control unit 72 executes at least one of the first to fourth control flows, similar to the control unit 72 in the fifth embodiment. By executing the control flows, the transmission mechanism 40 can easily change the gear ratio.

[0120] (Tenth embodiment) A drive unit 6 of the tenth embodiment will be described. Fig. 16 is used to describe the drive unit 6 of the tenth embodiment. The same reference numerals as those in the first to ninth embodiments are used for the components common to the first to ninth embodiments, and redundant description will be omitted.

[0121] In this embodiment, the transmission mechanism 40 is configured to rotate integrally with the output rotation shaft 30. At least one The intermediate shafts are connected to the output rotors 53. At least one The electric motor 62 includes an output shaft rotor 45. At least one It is connected to one of the intermediate shaft output rotors 53 . At least one an intermediate shaft output rotor 53; At least one The speed reducer is configured together with the output shaft rotor 45. An example of the speed change mechanism 40 is shown in FIG.

[0122] 16, the plurality of output shaft rotors 45 include two output shaft rotors 45. The two output shaft rotors 45 include a first output shaft rotor 45a and a second output shaft rotor 45c. At least one The intermediate shaft output rotors 53 include two intermediate shaft output rotors 53. The two intermediate shaft output rotors 53 include a first intermediate shaft output rotor 54 that meshes with the first output shaft rotor 45a, and a second intermediate shaft output rotor 85 that meshes with the second output shaft rotor 45c.

[0123] When the electric motor 62 is driven, the motor driving force is transmitted to the second intermediate shaft output rotor 85 via the first connecting gear 62a and the second connecting gear 62b. The motor driving force is transmitted to the output rotating shaft 30 via the second output shaft rotor 45c. In this embodiment, a reducer is disposed in the path along which the motor driving force is transmitted from the first connecting gear 62a to the output rotating shaft 30. Therefore, when the electric motor 62 is driven, the rotation speed of the output rotating shaft 30 is reduced relative to the rotation speed of the electric motor 62.

[0124] When the electric motor 62 is driven, the rotational speed of the output rotating shaft 30 decreases relative to the rotational speed of the electric motor 62, which eliminates the need to provide a separate reducer in the power transmission path from the electric motor 62 to the output rotating shaft 30, thereby reducing the number of parts.

[0125] The second connection gear 62b may be configured to mesh with the first relay shaft output rotor 54 instead of the second relay shaft output rotor 85. When the second connection gear 62b meshes with the first relay shaft output rotor 54, the rotational speed of the output rotating shaft 30 decreases relative to the rotational speed of the electric motor 62 when the electric motor 62 is driven in the transmission path of the motor driving force that is transmitted in this order through the first connection gear 62a, the second connection gear 62b, the first relay shaft output rotor 54, and the first output shaft rotor 45a.

[0126] (Eleventh embodiment) A drive unit 6 of the eleventh embodiment will be described. Fig. 17 is used to describe the drive unit 6 of the eleventh embodiment. The same reference numerals as those in the first to tenth embodiments are used for the components common to the first to tenth embodiments, and redundant description will be omitted.

[0127] In this embodiment, the transmission mechanism 89 of the drive unit 6 includes a continuously variable transmission mechanism or a planetary gear mechanism 90. Fig. 17 shows an example of the transmission mechanism 89. The transmission mechanism 89 shown in Fig. 17 is provided on the rear hub of a human-powered vehicle. The transmission mechanism 89 includes the planetary gear mechanism 90, at least one pawl 95, and a control member 96.

[0128] The planetary gear mechanism 90 includes at least one sun gear 91, at least one planet gear 92, a planet gear carrier 93, and at least one ring gear 94. The at least one sun gear 91 is mounted on a hub axle 98. The at least one sun gear 91 includes a first sun gear 91a, a second sun gear 91b, a third sun gear 91c, and a fourth sun gear 91d. The first sun gear 91a, the second sun gear 91b, the third sun gear 91c, and the fourth sun gear 91d are arranged to be aligned in the axial direction of the hub axle 98. The first sun gear 91a is fixed to the hub axle 98. The second sun gear 91b, the third sun gear 91c, and the fourth sun gear 91d are arranged to be selectively connectable to the hub axle 98 via at least one pawl 95. Each pawl 95 is configured similarly to, for example, at least one first pawl 57b shown in FIG. 3.

[0129] The at least one planetary gear 92 includes a first planetary gear 92a and a second planetary gear 92b. The first planetary gear 92a includes two externally toothed portions with different numbers of teeth. The two externally toothed portions are configured to mesh with the first sun gear 91a and the second sun gear 91b, respectively. The first planetary gear 92a is rotatably supported by a planetary gear carrier 93.

[0130] The second planetary gear 92b includes three externally toothed portions with different numbers of teeth. The three externally toothed portions are configured to mesh with the second sun gear 91b, the third sun gear 91c, and the fourth sun gear 91d, respectively. The second planetary gear 92b is rotatably supported by the planetary gear carrier 93.

[0131] The at least one ring gear 94 includes a first ring gear 94a and a second ring gear 94b. The first ring gear 94a is configured to mesh with the first planetary gear 92a. The second ring gear 94b is configured to mesh with the second planetary gear 92b.

[0132] The at least one pawl portion 95 includes a first pawl portion 95a, a second pawl portion 95b, and a third pawl portion 95c. The first pawl portion 95a is provided between the second sun gear 91b and the hub axle 98. The second pawl portion 95b is provided between the third sun gear 91c and the hub axle 98. The third pawl portion 95c is provided between the fourth sun gear 91d and the hub axle 98.

[0133] The control member 96 is configured to control the connection state between at least one sun gear 91 and the hub axle 98. The control member 96 is provided on the hub axle 98. The control member 96 rotates relative to the hub axle 98 to engage or disengage at least one pawl 95 from at least one sun gear 91. For example, the control member 96 engages the first pawl 95a with the second sun gear 91b to connect the second sun gear 91b to the hub axle 98.

[0134] The transmission path of the manual driving force in the drive unit 6 shown in Figure 17 will be described. The manual driving force is transmitted to the rear sprocket 5 shown in Figure 17 via the drive chain 4. When the rear sprocket 5 rotates due to the manual driving force, at least one ring gear 94 rotates integrally with the rear sprocket 5. The planetary gear carrier 93 rotates integrally with the at least one ring gear 94. As the planetary gear carrier 93 rotates, at least one planetary gear 92 rotates around at least one sun gear 91.

[0135] The at least one sun gear 91 around which the at least one planetary gear 92 rotates is switched depending on the connection state between the at least one sun gear 91 and the hub axle 98. For example, when the fourth sun gear 91d is connected to the hub axle 98, the second planetary gear 92b rotates around the fourth sun gear 91d in conjunction with the rotation of the at least one ring gear 94. The rotation of the at least one planetary gear 92 rotates the hub shell 99. In this embodiment, the gear ratio of the transmission mechanism 89 is changed depending on the connection state between the at least one sun gear 91 and the hub axle 98.

[0136] In the drive unit 6 shown in Fig. 17, the electric motor 62 is provided in the internal space of the hub shell 99 so that, for example, the motor driving force increases the rotational speed of the hub axle 98. By providing the electric motor 62 in the drive unit 6 shown in Fig. 17, the load on the transmission mechanism 89 in the rear hub can be reduced.

[0137] In this embodiment, the transmission mechanism 89 may include a planetary gear mechanism 90 different from that shown in Figure 17. The transmission mechanism 89 may include, for example, the planetary gear mechanism described in Japanese Patent No. 5649549. The present invention can also be applied to the drive unit described in Japanese Patent No. 5649549.

[0138] In this embodiment, the transmission mechanism 89 may include a continuously variable transmission mechanism instead of the planetary gear mechanism 90. The transmission mechanism 89 may include, for example, the continuously variable transmission mechanism described in German Patent Publication No. 10 20102 023 150 A1. The present invention can also be applied to the drive unit described in German Patent Publication No. 10 20102 023 150 A1.

[0139] (Variation) The description of each embodiment is merely an example of a form that the present invention can take, and is not intended to limit the present invention. For example, the present invention can take the form of a modified example of each embodiment shown below, or a combination of at least two modified examples that are not mutually contradictory.

[0140] For example, the configuration of the drive unit 6 in each embodiment is an example, and the drive unit 6 may include various devices not shown in each embodiment, or may be configured not to include some of the various devices shown in each embodiment.

[0141] The various thresholds used in the control illustrated in each embodiment are not limited and may be set arbitrarily. The various thresholds may be changed arbitrarily by operating a predetermined operating device, etc.

[0142] The configurations illustrated in each embodiment may be combined with each other to the extent that they are not mutually contradictory. The process contents and process order of the flowcharts illustrated in each embodiment are examples, and the process contents and process order can be changed as appropriate within the scope of the present invention.

[0143] The phrase "at least one" as used herein means "one or more" of the desired options. As an example, the phrase "at least one" as used herein means "only one option" or "both of two options" if the number of options is two. As another example, the phrase "at least one" as used herein means "only one option" or "any combination of two or more options" if the number of options is three or more. [Explanation of symbols]

[0144] 2a...crankshaft, 6...drive unit, 10...base portion, 20...input rotating shaft, 30...output rotating shaft, 40...transmission mechanism, 41...input section, 44...output section, 45...output rotor, 47...intermediate shaft, 50...intermediate shaft input rotor, 53...intermediate shaft output rotor, 56...connection portion, 62...electric motor, 72...control portion

Claims

1. A drive unit for a human-powered vehicle, A base portion; an electric motor provided on the base and configured to provide a propulsive force to the human-powered vehicle; an input rotation shaft rotatably provided on the base portion and adapted to receive a manual driving force; an output rotation shaft rotatably provided on the base portion, to which a manual driving force is transmitted from the input rotation shaft and to which a motor driving force is transmitted from the electric motor; a transmission mechanism provided in the base portion on a transmission path of the human-powered driving force between the input rotation shaft and the output rotation shaft, the transmission mechanism being configured to change a transmission ratio; a controller configured to control the electric motor; the transmission mechanism includes an input portion connected to the input rotary shaft and an output portion connected to the output rotary shaft, the electric motor is connected to the output portion of the transmission mechanism without passing through the input portion of the transmission mechanism; the control unit controls the electric motor so that the motor driving force increases when the speed change ratio of the transmission mechanism is changed, regardless of the state of the manual driving force at the time the speed change ratio is changed; The transmission mechanism is an intermediate shaft provided on the base portion and rotatable by the manual driving force from the input rotation shaft; a plurality of intermediate shaft input rotors that are selectively connectable to the intermediate shaft and connected to the input rotor; a connection portion configured to selectively connect the plurality of intermediate shaft input rotors to the intermediate shaft so that the manual driving force is transmitted to the intermediate shaft; at least one intermediate shaft output rotor provided on the intermediate shaft and connected to the output rotor; the electric motor is connected to the intermediate shaft without passing through the plurality of intermediate shaft input rotors, The control unit increases the motor driving force when the connection state between the intermediate shaft input rotors and the intermediate shaft is changed by the connection unit.

2. The at least one intermediate shaft output rotor includes a plurality of intermediate shaft output rotors, the plurality of intermediate shaft output rotors are provided so as to be selectively connectable to the intermediate shaft, The drive unit according to claim 1 , wherein the connection portion is configured to selectively connect the plurality of intermediate shaft output rotors to the output rotation shaft so that the manual driving force is transmitted to the output rotation shaft.

3. A drive unit as described in claim 1 or 2, wherein the control unit increases the motor driving force before changing the connection state between the multiple intermediate shaft input rotors and the intermediate shafts by the connection unit.

4. The transmission mechanism the at least one output shaft rotor configured to rotate integrally with the output rotor shaft and connected to the at least one intermediate shaft output rotor, the electric motor is connected to any one of the at least one intermediate shaft output rotors; 3. The drive unit according to claim 1, wherein the at least one intermediate shaft output rotor and the at least one output shaft rotor constitute a reducer.

5. A drive unit as described in claim 1, wherein the transmission mechanism includes a continuously variable transmission mechanism or a planetary gear mechanism.

6. A drive unit as described in claim 1 or 2, wherein the input rotating shaft includes a crankshaft.

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