TW202140322A - Mid-mounted motor device and electric bicycle transmission system enabling the power of the center axle rotating in the backward direction to be transmitted to the coaster brake module to perform braking - Google Patents

Abstract

This invention relates to a mid-mounted motor device with coaster brake function, which is suitable for being installed to an electric bicycle comprising a pedal chainwheel, a chain, and a coaster brake module. The mid-mounted motor device comprises a central axle, a motor drive unit, and a moving unit. The central axle can rotate in a forward direction or a backward direction with an axle axis as the axis and has a central axle guiding part. The motor drive system comprises a core gear and a mid-mounted motor for driving the core gear. The moving unit can move in a forward position and a coaster brake position along the extending direction of the axis and comprises a moving guide part corresponding to the central axle guide part. At the coaster brake position, the moving unit is butted with the core gear, so that the power of the center axle rotating in the backward direction can be transmitted to the coaster brake module via the core gear, the pedal chainwheel, and the chain to perform braking.

Description

Mid-mounted motor device and electric bicycle transmission system

The invention relates to an electric bicycle, in particular to a central motor device with a rear brake function and an electric bicycle transmission system.

A conventional mid-mounted motor is suitable for installation on the center shaft of an electric bicycle. The mid-mounted motor drives the internal gear mechanism to rotate, and outputs power through a core gear, a chainring to a chain, and then drives the rear wheel Rotate to achieve the purpose of driving the wheels to rotate with electricity. In addition, the aforementioned electric bicycle can also be driven forward by the user stepping on the pedals, and the power of the user stepping on the pedals passes through the corresponding crank, the central shaft, the core gear teeth to the chain, and then drives the rear wheel to rotate.

However, the aforementioned central motor has a one-way backstop mechanism (such as one-way ratchet, one-way clutch) between its core gear and the central shaft. Therefore, when the user steps on the pedals backward, the central shaft Because of the aforementioned one-way backstop mechanism, the power cannot be transmitted to the core gear teeth. Therefore, the conventional coaster brake module cannot be driven by the chain to brake, and the rear brake cannot be used for braking.

Therefore, the object of the present invention is to provide a central motor device with a rear brake function.

Therefore, the central motor device of the present invention is suitable for installation on an electric bicycle including a rear brake module. The electric bicycle also includes two pedals, two cranks connected to the pedals at one end, a pedal chain, and a chain connected to the pedal chain and the rear brake module. The pedal crank can rotate around an axis in a forward direction or a backward direction. The central motor device includes a central shaft, a motor drive unit, and a moving unit.

The two ends of the central shaft are respectively suitable for piercing one end of the cranks away from the pedals and can rotate in the forward direction or the backward direction with the axis as the axis. The central shaft has a central shaft guiding part.

The motor drive unit includes a core gear suitable to be arranged around the pedal chain and rotated by the pedal chain, and a central motor for outputting power to rotate the core gear in the forward direction , And a first backstop arranged between the central shaft and the core gear teeth. The first backstop is used for interruptingly transmitting the rotation power of the central shaft to the core gear.

The moving unit is arranged around the central shaft and can move in a forward position and a foot brake position along the extension direction of the axis, and includes a moving guide part corresponding to the central shaft guide part. By means of the cooperation of the moving guide portion and the central shaft guiding portion, when the central shaft rotates in the forward direction, the moving unit is driven to move away from the forward position of the core gear along the extending direction of the axis, And when the central shaft rotates in the retreat direction, the moving unit is driven to move along the extension direction of the axis to the foot brake position close to the core wheel tooth. At the foot brake position, the moving unit abuts the core wheel tooth so that The power of the center shaft rotating in the backward direction can be transmitted to the rear brake module via the core gear, the pedal chain, and the chain to perform braking.

Therefore, another object of the present invention is to provide an electric bicycle transmission system with a rear brake function.

Therefore, the electric bicycle transmission system of the present invention includes a rear brake module, two pedals, two cranks, a pedal chainring, a chain, and the aforementioned central motor device.

The cranks are connected to the pedals at one end, respectively.

The pedal crank can rotate around an axis in a forward direction or a backward direction.

The chain chain is combined with the pedal chainring and the rear brake module.

The effect of the present invention is that by providing a moving unit matched with the central axis, when the pedals are stepped back, the central axis can be dynamically connected to the pedal chain through the core gear, thereby enabling the movement in the backward direction The pedaling kinetic energy is transmitted to the rear brake module for braking.

1 and 2, an embodiment of the electric bicycle transmission system of the present invention is suitable for installation in an electric bicycle 100, and includes a pedal unit 10, and a central motor device 20 disposed on the pedal unit 10 .

The pedal unit 10 includes a rear brake module 101, two pedals 102 suitable for pedaling, two cranks 103 respectively connected to the pedals 102, and one connected to the cranks 103 and capable of encircling an axis X in a forward direction A or a pedal crank 104 that rotates in the backward direction B, a rear wheel crank 105 suitable for being arranged on a rear wheel 107 and power connected to the rear brake module 101, and a link between the pedal crank 104 and The chain 106 of the rear brake module 101.

The function of the rear brake module 101 is that when the user steps on the pedals 102 and the cranks 103 are linked to rotate the pedal chain 104 in the backward direction B, power can be output to the rear brake module 101, and the rear wheel 107 can be stopped from rotating, thereby achieving the braking function. You can refer to Taiwan Patent Publication No. TW201806791A and other related documents or videos related to coaster brakes. Since those with ordinary knowledge in the field can infer the expansion details based on the above description, no further description is given here.

Referring to FIGS. 2 and 3, the central motor device 20 includes a central shaft 2, a motor drive unit 3, and a moving unit 4.

The two ends of the central shaft 2 are respectively suitable for piercing one end of the cranks 103 away from the pedals 102, and can rotate in the forward direction A or the backward direction B with the axis X as the axis. The central shaft 2 has a central shaft引部21。 Leading part 21.

The motor drive unit 3 includes a core gear 32 adapted to be arranged around the pedal chain 104 and rotated by the pedal chain 104, and a core gear 32 for outputting power so that the core gear 32 moves in the forward direction A rotating central motor 20, a first backstop 33 arranged between the central shaft 2 and the core gear 32, and a circuit group 34 electrically connected to the central motor 20.

Referring to FIGS. 3, 4 and 5, the core gear 32 has a first end surface 321 facing the moving unit 4 described later, and three first abutting portions 322 formed on the first end surface 321. In this embodiment, each first mating portion 322 is a concave portion, and has a blocking surface 323, a horizontal surface 324 connected to the blocking surface 323, and an inclined surface 325 connected to the horizontal surface 324.

2 and 3, the first backstop 33 is used to interrupt the transmission of the rotation power of the central shaft 2 to the core gear 32, the first backstop 33 can be driven by the central shaft 2 to operate on a Switch between a closed state, an open state, and a functional stop state. In the closed state, the first backstop 33 is used to transmit the rotational power of the center shaft 2 to the core gear 32, in the open state and the function In the stopped state, the first backstop 33 interrupts the transmission of the rotational power of the central shaft 2 to the core gear 32.

It is worth noting that the first check member 33 is a one-way ratchet or a one-way clutch. In this embodiment, the first check member 33 is a one-way clutch.

It is further explained that, according to the running direction and rotation speed of the central shaft 2 and the core gear 32, the detailed conditions of the first backstop 33 in the aforementioned closed state, open state, and function stop state are shown in the following table: The center shaft 2 and the core gear 32 both rotate in the forward direction A (the ω below represents the angular velocity) Condition 1: ω central axis 2≧ω core gear 32 The first backstop 33: in the closed state Condition 2: ω central axis 2>ω core gear 32 The first backstop 33: in the open state The center shaft 2 rotates in the backward direction B, so that the moving unit 4 locks the core gear 32 Condition 3: The first non-stop member 33 is in the function stop state, and the pedals 102 are dynamically connected to the pedal crank 104 through the moving unit 4 as a whole.

In the above table, both conditions 1 and 2 are when the user is stepping on the pedals 102 and the pedals 102 drive the central shaft 2 to rotate in the forward direction A, and the condition 3 is when the user is stepping on the pedals backward. The pedals 102 enable the pedals 102 to drive the central shaft 2 to rotate in the backward direction B.

Referring to Figures 1 to 3, condition 1 is that the rotational angular velocity of the central shaft 2 (driven by the pedals 102) is greater than or equal to the rotational angular velocity of the core gear 32 (driven by the central motor 20), that is, the user's foot The angular velocity of the pedal drive is greater than or equal to the angular velocity of the electric drive. At this time, the first backstop 33 is in the closed state, that is, the power output by the pedals 102 can pass through the crank 103, the central shaft 2, The core gear 32, the pedal chainring 104, the chain 106 to the rear chainring 105, and the power output by the central motor 20 can also pass through the core gear 32, the pedal chainring 104, and the chain 106 to the rear wheel crank 105, in other words, at this time, the electric bicycle 100 is driven by the pedal and the central motor 20 at the same time.

Condition 2 is that the rotational angular velocity of the central shaft 2 is less than the rotational angular velocity of the core gear 32, that is, the angular velocity of the user's pedal drive is less than the angular velocity of the electric drive. At this time, the first backstop 33 is in the open state, and In other words, the power output by the central motor 20 can be output to the rear chainring 105, but due to the action of the first backstop 33, the power output by the pedals 102 cannot be transmitted to the core gear 32. Moreover, the power of the chain 106 rotation cannot drive the pedals 102 to rotate through the core gear 32, the central shaft 2, and the crank 103. In other words, at this time, the electric bicycle 100 is only driven by the central motor 20. In this way, it is possible to avoid the pedaling phenomenon caused by the passive rotation of the pedals 102, thereby allowing the user to obtain a smooth riding effect.

Situation 3 is the situation when the user steps on the pedals 102 backward when the user wants to brake. At this time, the moving unit 4 moves to the end of the core gear 32 until the core gear 32 is locked, so that the pedals 102 and the center shaft 2 By means of the moving unit 4, the core gear 32 and the pedal crank 104 are dynamically connected as a whole, and the first backstop 33 is in the functional stop state. Preferably, it is a structural connection in this embodiment And fixed as one. In this way, the user can achieve the purpose of braking by stepping on the pedals 102 backward. It is worth noting that this braking action is completely realized by the mechanical structure. For detailed description, please refer to the description in the following paragraphs.

The circuit set 34 includes a sensing element 342 for sensing whether the central shaft 2 is rotating in the forward direction A or the backward direction B, and a control element electrically connected to the sensing element 342 and the central motor 20 343. When the central shaft 2 rotates in the backward direction B, the control member 343 controls the central motor 20 to stop running.

It is worth noting that the control member 343 can also reduce or immediately stop the inertial movement of the central motor 20 by reducing electromagnetic damping.

In addition, it is worth noting that in this embodiment, the brake is braked through the mechanism and the control of the central motor. However,

Referring to Figures 2, 3 and 4, the moving unit 4 is arranged around the central shaft 2 and can move along the extension direction of the axis X in a forward position (Figure 2) and a foot brake position (Figure 3) , And includes a moving part 42 and a second backstop 41.

The moving member 42 has a butting surface 421 facing the first end surface 321, three second butting portions 422 formed on the abutting surface 421 and positioned on the first abutting portions 322, and a second abutting portion 422 that surrounds the axis X and is located outside的flexible part 423.

Referring to FIG. 5, in this embodiment, each second mating portion 422 is a bump. When the moving unit 4 is displaced from the forward position (as shown in FIG. 3) to the foot brake position (as shown in FIG. 2), each of the second docking portions 422 sequentially comes from the inclined surface of the corresponding first docking portion 322 325. The horizontal plane 324 moves and abuts against the blocking surface 323, so that the moving unit 4 is abutted with the core gear 32 to transmit power.

It is worth noting that in this embodiment, each first abutting portion 322 is a concave portion, and each second abutting portion 422 is a bump. In other variations of this embodiment, each first abutting portion 322 It may also be a bump, and each second mating portion 422 is a concave portion that is aligned with the corresponding first mating portion 322. In addition, in this embodiment, the first docking portions 322 and the second docking portions 422 are arranged equiangularly around the axis X, and the number is three. In other variations of this embodiment, the aforementioned first docking portion The number of the mating portion 322 and the aforementioned second mating portion 422 can also be one or more than three, and the axis X does not need to be arranged equiangularly, as long as the aforementioned first mating portion 322 and the aforementioned second mating portion 422 can be When the moving unit 4 is displaced from the forward position to the foot brake position, it can be connected to each other, so that the purpose of the embodiment can be achieved.

Referring to FIGS. 2 and 3, the second backstop 41 has a movement guide portion 411 formed on the inner side and corresponding to the central axis guide portion 21. In this embodiment, the second backstop 41 is a one-way clutch.

In this embodiment, the central shaft guiding portion 21 of the central shaft 2 is an external helical tooth provided on the outer surface of the central shaft 2 around the axis X, and the movement guiding portion 411 of the moving unit 4 is provided around the axis X It is on the inner surface of the moving unit 4 and corresponds to the inner helical teeth of the central axis guide 21. In other variations of this embodiment, the same function can also be achieved through mutually corresponding screw structures.

The movement guide portion 411 cooperates with the central shaft guide portion 21, so that when the central shaft 2 rotates in the forward direction A, the moving unit 4 is driven to move away from the core gear 32 along the extension direction of the axis X. The forward position (as shown in Figure 3) moves, and when the central shaft 2 rotates in the backward direction B, the moving unit 4 is driven to move along the extension direction of the axis X to the foot brake position close to the core gear 32 At the foot brake position (as shown in Fig. 2), the moving unit 4 abuts the core gear 32, so that the power of the central shaft 2 rotating in the backward direction B can pass through the core gear 32 and the pedal chain 104 , The chain 106 is transmitted to the rear brake module 101 for braking.

Referring to Figures 1, 2 and 3, when a user wants to use a foot brake, he only needs to step on the pedals 102 to make the cranks 103 rotate in the backward direction B, and the center shaft 2 can be driven to rotate in the backward direction B. When the mobile unit 4 is linked to move to the foot brake position, when the foot brake position (as shown in FIG. 2) is reached, the second abutting portions 422 of the mobile unit 4 abut the first abutting portions 322 of the core gear 32 , The power for rotating the center shaft 2 in the backward direction B can be transmitted to the rear brake module 101 via the core gear 32, the pedal chain 104, and the chain 106 to perform braking.

In this way, in the present invention, the user only needs to step on the pedals 102 backwards, move to the braking position through the moving unit 4 and engage with the core gear 32, so that the pedals 102, the cranks 103, and the moving unit 4 , The core gear 32 is dynamically connected to the pedal crank 104 and rotates in the backward direction, thereby driving the rear brake module 101 to brake. That is, in this case, when the center-mounted motor 20 is driven without power (for example, the battery is dead, and the battery is not used), the braking function can still be guaranteed.

In addition, when the sensing element 342 of the circuit group 34 detects that the central shaft 2 is in the backward direction B, the control element 343 also controls the central motor 20 to stop running, reducing the inertial rotation and rotation of the central motor 20 Damping, thereby, can achieve the effect of auxiliary braking.

When the braking is over and the forward state is to be restored, the user only needs to step on the pedals 102 to rotate the cranks 103 in the forward direction A, and then the center shaft 2 can be driven to link the moving unit when rotating in the backward direction B. 4 moves along the forward position, and when it reaches the forward position (as shown in FIG. 3), the second abutting portions 422 of the moving unit 4 disengage from the first abutting portion 322 that abuts the core gear 32, and maintain the original Riding status.

Based on the above description, the advantages of the foregoing embodiments can be summarized as follows:

1. By arranging the moving unit 4 that cooperates with the central shaft 2, when the pedals 102 are stepped back, the central shaft 2 can be dynamically connected to the pedal ring 104 through the core gear 32, so as to be able to move along the The pedaling kinetic energy in the backward direction B is transmitted to the rear braking module 101 to perform braking.

2. Since the central axis guide portion 21 and the movement guide portion 411 are both helical tooth structures, the smoothness and consistency of the movement of the moving assembly can be maintained.

3. Through the design of the inclined surface 325, the horizontal plane 324, and the stopping surface 323 of each first abutting portion 322, and the design of the elastic portion 423 of the movable member 42, the second abutting portions 422 can be made to be respectively When aligned to the first docking portions 322, a smoother alignment process can be achieved, so as to correct or ensure the smoothness and consistency of the mobile unit 4 during the movement.

4. To sum up, in this case, when the central motor 20 is not driven by electricity, it can still ensure that the user achieves the braking function by pedaling.

However, the above are only examples of the present invention, and should not be used to limit the scope of implementation of the present invention, all simple equivalent changes and modifications made in accordance with the scope of the patent application of the present invention and the content of the patent specification still belong to This invention patent covers the scope.

100: Bicycle 10: Foot unit 101: Rear brake module 102: Pedal 103: crank 104: Pedal Crankset 105: rear chainring 106: chain 107: rear wheel 20: Mid-mounted motor device 2: bottom bracket 21: Bottom guide 3: Motor drive unit 31: Mid-mounted motor 32: core gear teeth 321: first end face 322: The first docking part 323: Blocking Surface 324: horizontal plane 325: Inclined surface 33: The first backstop 34: Circuit Group 341: Circuit Board 342: Sensor 343: control 4: mobile unit 41: second backstop 411: Mobile Guide 42: moving parts 421: Butt Surface 422: The second docking part 423: Elastic part A: Forward direction B: Backward direction X: axis

Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, in which: Figure 1 is a schematic side view illustrating that an embodiment of the electric bicycle transmission system of the present invention is installed on an electric bicycle; 2 and 3 are incomplete cross-sectional schematic diagrams, and the mobile unit of this embodiment is located at a foot brake position and a forward position; Figure 4 is a cross-sectional view taken along the line IV-IV in Figure 2; and Fig. 5 is an incomplete schematic cross-sectional view of Fig. 4;

101: Rear brake module

102: Pedal

103: crank

104: Pedal Crankset

106: chain

20: Mid-mounted motor device

2: bottom bracket

21: Bottom guide

3: Motor drive unit

31: Mid-mounted motor

32: core gear teeth

322: The first docking part

33: The first backstop

34: Circuit Group

341: Circuit Board

342: Sensor

343: control

4: mobile unit

41: second backstop

411: Mobile Guide

42: moving parts

422: The second docking part

423: Elastic part

A: Forward direction

B: Backward direction

X: axis

Claims (8)

A mid-mounted motor device suitable for installation on an electric bicycle including a rear brake module. The electric bicycle further includes two pedals, two cranks connected to the pedals at one end, a pedal crank, and a chain A chain that fits the pedal crank and the rear brake module, the pedal crank can rotate around an axis in a forward direction or a backward direction, and the central motor device includes: A central shaft, both ends are respectively suitable for piercing one end of the cranks away from the pedals, and can rotate in the forward direction or the backward direction with the axis as the axis, and the central shaft has a central shaft guiding part; A motor drive unit includes a core gear suitable to be arranged around the pedal chain and rotated by the pedal chain, and a central gear for outputting power to rotate the core gear in the forward direction A motor, and a first backstop arranged between the center shaft and the core gear, the first backstop is used to interrupt the transmission of the rotation power of the center shaft to the core gear; and A moving unit is arranged around the central shaft and can move in a forward position and a foot brake position along the extension direction of the axis, and includes a pair of moving guide parts corresponding to the central shaft guide part, by means of the moving guide part Cooperating with the central shaft guide portion, when the central shaft rotates in the forward direction, the moving unit is driven to move away from the forward position of the core gear along the extending direction of the axis, and the central shaft is moved along the forward direction. When rotating in the backward direction, the moving unit is driven to move along the extension direction of the axis toward the foot brake position close to the core gear. At the foot brake position, the moving unit abuts the core gear so that the central shaft moves in the backward direction The rotating power can be transmitted to the rear brake module through the core gear, the pedal chainring, and the chain to perform braking. The central motor device according to claim 1, wherein the central shaft guide portion of the central shaft is an external helical tooth provided on the outer surface of the central shaft around the axis, and the movement guide portion of the moving unit surrounds the axis Internal oblique teeth arranged on the inner surface of the mobile unit. The mid-mounted motor device according to claim 1, wherein the core gear has a first end surface facing the moving unit, and at least one first abutting portion formed on the first end surface, and the moving unit has at least one The at least one second butting portion is mutually butted with the same number of second butting portions, the at least one first butting portion is one of a concave portion and a convex block, and the at least one second butting portion is the other of a concave portion and a convex block By. The mid-mounted motor device according to claim 3, wherein the at least one first abutting portion is a concave portion and has a blocking surface, a horizontal plane connecting the blocking surface, and an inclined surface connecting the horizontal plane, the The at least one second butting portion is a bump. When the moving unit is displaced from the forward position to the foot brake position, the at least one second butting portion is in sequence from the inclined surface and the horizontal plane of the corresponding first butting portion It moves and abuts against the stopping surface, so that the moving unit is butted with the core gear to transmit power. The central motor device according to claim 1, wherein the first backstop can be switched between a closed state and an open state by the operation, and in the closed state, the first backstop is used to transmit The rotation power of the central shaft is transmitted to the core gear. In the open state, the first backstop interrupts the transmission of the rotation power of the central shaft to the core gear, and the central shaft and the core gear rotate in the forward direction And when the central shaft rotates in the backward direction relative to the core gear, the first backstop is in the closed state. The central motor device according to claim 5, wherein the first backstop is a one-way ratchet or a one-way clutch. The center-mounted motor device according to claim 1, wherein the motor drive unit further includes a circuit group electrically connected to the center-mounted motor, and the circuit group includes a circuit group for sensing whether the center shaft is in the forward direction or the forward direction. A sensing element that rotates in the backward direction, and a control element electrically connected to the sensing element and the central motor. When the central shaft rotates in the backward direction, the control element controls the central motor to stop running. An electric bicycle transmission system, including: One rear brake module; Two pedals Two cranks, each connected to the pedals at one end; A pedal crank, which can rotate around an axis in a forward direction or a backward direction; A chain which is connected to the pedal chainring and the rear brake module; and The mid-mounted motor device described in any one of claims 1-7.

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