Bicycle driving system and sensing ratchet wheel set thereof

Abstract

The utility model provides a driving system of a bicycle. The driving system comprises a fluted disc, a chain, a flywheel and a sensing ratchet wheel set. And the flywheel is synchronously linked with the fluted disc through a chain. The sensing ratchet group is connected to the flywheel. The sensing ratchet wheel set comprises a ratchet wheel seat, a ratchet wheel shell, a bottom cover and a whole vehicle rotating speed sensor. The ratchet shell is rotatably arranged on the ratchet seat. The bottom cover is rotatably arranged at the end part of the ratchet wheel seat; and the whole vehicle rotating speed sensor is arranged between the ratchet wheel seat and the bottom cover. The whole vehicle rotating speed sensor is used for sensing the rotating speed of the ratchet wheel seat relative to the bottom cover. If the tooth ratio of the flywheel to the fluted disc is adjusted to be between 1 and 0.5, the number of pulse signals output by the whole vehicle rotating speed sensor is between 24 and 150 every time the fluted disc rotates by one circle.

Description

Technical Field

[0001] The utility model relates to a bicycle sensing architecture, in particular to a drive system and a sensing ratchet set suitable for a bicycle. Background Art

[0002] With the continuous improvement of people's requirements for intelligent travel, assisted bicycles are increasingly favored by people. At present, assisted bicycles with torque sensors need to cooperate with the pedaling frequency and pedaling direction to better control the startup, power-off, and assisting force of the motor. Currently, torque sensing is usually performed on the front drive module. However, the currently used torque sensors have low sensitivity, and the detection of the front drive module requires the rider to actively pedal to effectively detect. The sudden speed reduction problem caused by road conditions and the sudden increase in the assisting force requirement are easily not detected and thus effective assistance cannot be provided. Summary of the Utility Model

[0003] The utility model provides a sensing ratchet set that can effectively improve the transmission sensitivity of the rear wheel and a bicycle equipped with this sensing ratchet set to solve the above problems.

[0004] Based on the above purpose, the utility model provides a bicycle drive system, which includes: a chainring that rotates with human input; a chain that connects the chainring; a freewheel that includes a plurality of teeth stacked coaxially on the rear wheel axle, and the freewheel is connected to the chain through one of the plurality of teeth, so that the freewheel is driven by the chain and linked with the chainring; and

[0005] a sensing ratchet set axially connected to one side of the freewheel, the sensing ratchet set includes: a ratchet seat; a ratchet housing rotatably arranged on the ratchet seat; a bottom cover rotatably arranged at the end of the ratchet seat; and a vehicle speed sensor arranged between the ratchet seat and the bottom cover, the vehicle speed sensor is used to sense the rotation speed of the ratchet seat relative to the bottom cover; wherein, when the gear ratio between the freewheel and the chainring is adjusted to be between 1 and 0.5, when the chainring rotates one circle, the number of pulse signals output by the vehicle speed sensor is between 24 and 150.

[0006] Preferably, the vehicle speed sensor includes: a vehicle speed sensing element fixed to the ratchet seat; and a vehicle speed sensing module fixed to the bottom cover and opposite to the vehicle speed sensing element; wherein, when the ratchet seat rotates relative to the bottom cover, the vehicle speed sensing module senses the vehicle speed sensing element and outputs a plurality of first vehicle speed pulse signals and a plurality of second vehicle speed pulse signals, and the phase difference between the plurality of first vehicle speed pulse signals and the plurality of second vehicle speed pulse signals is 90 degrees.

[0007] Preferably, the vehicle speed sensing module includes a first vehicle speed sensor and a second vehicle speed sensor. The first vehicle speed sensor and the second vehicle speed sensor are arranged in a straight line along the radial direction of the vehicle speed sensing module. The vehicle speed sensing element includes a plurality of first vehicle speed target elements and a plurality of second vehicle speed target elements. The plurality of first vehicle speed target elements and the plurality of second vehicle speed target elements are arranged in two adjacent rings and are offset from each other. The first vehicle speed sensor senses the plurality of first vehicle speed target elements and outputs the plurality of first vehicle speed pulse signals. The second vehicle speed sensor senses the plurality of second vehicle speed target elements and outputs the plurality of second vehicle speed pulse signals.

[0008] Preferably, the vehicle speed sensing module further includes a position sensor. The first vehicle speed sensor, the second vehicle speed sensor and the position sensor are arranged in a straight line along the radial direction of the vehicle speed sensing module. The vehicle speed sensing element includes a position target element. When the toothed disc rotates one circle, the position sensor senses the position target element and outputs a position pulse signal.

[0009] Preferably, the vehicle speed sensing module includes a first vehicle speed sensor and a second vehicle speed sensor. The first vehicle speed sensor and the second vehicle speed sensor are arranged at an angular interval of 90 degrees. The vehicle speed sensing element includes a plurality of vehicle speed target elements. The plurality of vehicle speed target elements are arranged in a ring. The first vehicle speed sensor senses the plurality of vehicle speed target elements and outputs the plurality of first vehicle speed pulse signals. The second vehicle speed sensor senses the plurality of vehicle speed target elements and outputs the plurality of second vehicle speed pulse signals.

[0010] Preferably, the vehicle speed sensing module further includes a position sensor. The first vehicle speed sensor and the position sensor are arranged in a straight line along the radial direction of the vehicle speed sensing module. The vehicle speed sensing element includes a position target element. When the toothed disc rotates one circle, the position sensor senses the position target element and outputs a position pulse signal.

[0011] Preferably, the sensing ratchet set further includes a reverse speed sensor, which is arranged between the ratchet seat and the ratchet housing. The reverse speed sensor is used to sense the rotation speed of the ratchet housing relative to the ratchet seat. The reverse speed sensor includes:

[0012] A reverse speed sensing element, fixed to the ratchet housing; and

[0013] A reverse speed sensing module, fixed to the ratchet seat and opposite to the reverse speed sensing element;

[0014] Wherein, when the ratchet housing rotates relative to the ratchet seat, the reverse rotational speed sensing module senses the reverse rotational speed sensing element and outputs a plurality of first reverse rotational speed pulse signals and a plurality of second reverse rotational speed pulse signals, and the phase difference between the plurality of first reverse rotational speed pulse signals and the plurality of second reverse rotational speed pulse signals is 90 degrees.

[0015] Preferably, the reverse rotational speed sensing module includes a first reverse rotational speed sensor and a second reverse rotational speed sensor. The first reverse rotational speed sensor and the second reverse rotational speed sensor are linearly arranged along the axial direction of the reverse rotational speed sensing module. The reverse rotational speed sensing element includes a plurality of first reverse rotational speed target elements and a plurality of second reverse rotational speed target elements. The plurality of first reverse rotational speed target elements and the plurality of second reverse rotational speed target elements are arranged in two adjacent rings and are mutually offset. The first reverse rotational speed sensor senses the plurality of first reverse rotational speed target elements and outputs the plurality of first reverse rotational speed pulse signals, and the second reverse rotational speed sensor senses the plurality of second reverse rotational speed target elements and outputs the plurality of second reverse rotational speed pulse signals.

[0016] Preferably, the reverse rotational speed sensing module further includes a position sensor. The first reverse rotational speed sensor, the second reverse rotational speed sensor, and the position sensor are linearly arranged along the axial direction of the reverse rotational speed sensing module. The reverse rotational speed sensing element includes a position target element; when the toothed disk rotates one circle, the position sensor senses the position target element and outputs a position pulse signal.

[0017] Preferably, the reverse rotational speed sensing module includes a first reverse rotational speed sensor and a second reverse rotational speed sensor. The first reverse rotational speed sensor and the second reverse rotational speed sensor are arranged at an angular interval of 90 degrees. The reverse rotational speed sensing element includes a plurality of reverse rotational speed target elements. The plurality of reverse rotational speed target elements are arranged in a ring. The first reverse rotational speed sensor senses the plurality of reverse rotational speed target elements and outputs the plurality of first reverse rotational speed pulse signals, and the second reverse rotational speed sensor senses the plurality of reverse rotational speed target elements and outputs the plurality of second reverse rotational speed pulse signals.

[0018] Preferably, the reverse rotational speed sensing module further includes a position sensor. The first reverse rotational speed sensor and the position sensor are linearly arranged along the axial direction of the reverse rotational speed sensing module. The reverse rotational speed sensing element includes a position target element; when the toothed disk rotates one circle, the position sensor senses the position target element and outputs a position pulse signal.

[0019] Preferably, the sensing ratchet set further includes a processor and a torque measurement module. The torque measurement module is used to measure the torque applied to the sensing ratchet set, and the processor obtains the pedaling power according to the torque.

[0020] For the above purposes, the present utility model further provides a bicycle drive system, which includes: a chainring that rotates with the input of human power; a chain that connects the chainring; a freewheel that includes a plurality of teeth stacked coaxially on the rear wheel axle, and the freewheel is connected to the chain through one of the plurality of teeth, so that the freewheel is driven by the chain and interlocks with the chainring; and

[0021] a sensing ratchet assembly axially connected to one side of the freewheel. The sensing ratchet assembly includes: a ratchet seat; a ratchet housing rotatably arranged on the ratchet seat; a bottom cover rotatably arranged at the end of the ratchet seat; and a vehicle speed sensor arranged between the ratchet seat and the bottom cover. The vehicle speed sensor is used to sense the rotation speed of the ratchet seat relative to the bottom cover. Wherein, the percentage of the gear ratio between the freewheel and the chainring and the number of pulse signals output by the vehicle speed sensor is between 0.33% and 4.17%.

[0022] For the above purposes, the present utility model further provides a sensing ratchet assembly, which includes: a ratchet seat; a ratchet housing rotatably arranged on the ratchet seat; a bottom cover rotatably arranged at the end of the ratchet seat; and

[0023] a vehicle speed sensor arranged between the ratchet seat and the bottom cover. The vehicle speed sensor is used to sense the rotation speed of the ratchet seat relative to the bottom cover. The vehicle speed sensor includes: a vehicle speed sensing element fixed to the ratchet seat; and a vehicle speed sensing module fixed to the bottom cover and opposite to the vehicle speed sensing element. Wherein, when the ratchet seat rotates relative to the bottom cover, the vehicle speed sensing module senses the vehicle speed sensing element and outputs a plurality of first vehicle speed pulse signals and a plurality of second vehicle speed pulse signals, and the phase difference between the plurality of first vehicle speed pulse signals and the plurality of second vehicle speed pulse signals is 90 degrees.

[0024] Preferably, when the ratchet seat rotates one circle relative to the bottom cover, the number of pulse signals output by the vehicle speed sensor is between 24 and 150.

[0025] In summary, the sensing ratchet assembly of the present utility model is installed on the freewheel of the rear transmission assembly. When the gear ratio between the freewheel and the chainring is between 1 and 0.5, and the freewheel rotates one circle, the number of pulse signals output by the vehicle speed sensor is between 24 and 150. Thereby, when the gear ratio is less than 1, the number of pulse signals output by the vehicle speed sensor can be effectively increased, and further the rear wheel transmission sensitivity of the assisted bicycle can be improved. In an embodiment, the present utility model can make the phase difference between the first vehicle speed pulse signal and the second vehicle speed pulse signal output by the vehicle speed sensing module be 90 degrees to increase the number of pulse signals output by the vehicle speed sensor. Description of the Drawings

[0026] Figure 1Schematic diagram of an assisted bicycle according to an embodiment of the present utility model.

[0027] Figure 2 It is Figure 1 The side view of the rear drive module in

[0028] Figure 3 It is Figure 2 The exploded view of the rear drive module in

[0029] Figure 4 It is Figure 3 The perspective view of the sensing ratchet set in

[0030] Figure 5 It is Figure 3 The exploded view of the sensing ratchet set in

[0031] Figure 6 It is Figure 5 The perspective view of the ratchet housing in

[0032] Figure 7 It is Figure 5 The perspective view of the ratchet seat in

[0033] Figure 8 It is Figure 5 The top view of the vehicle speed sensor in

[0034] Figure 9 It is Figure 5 The perspective view of the reverse speed sensor in

[0035] Figure 10 Schematic diagram of a pulse signal in digital form.

[0036] Figure 11 Schematic diagram of a pulse signal in analog form.

[0037] Figure 12 Top view of the vehicle speed sensor according to another embodiment of the present utility model.

[0038] Figure 13 Perspective view of the reverse speed sensor according to another embodiment of the present utility model. Detailed implementation manners

[0039] To further understand the purpose, structure, features, and functions of the present utility model, the following is a detailed description in conjunction with embodiments.

[0040] Regarding the power sensing of the bicycle in the following embodiments of the present utility model, please refer to Figures 1 to 11 , Figure 1 Schematic diagram of a bicycle 1 according to an embodiment of the present utility model, Figure 2 It is Figure 1Side view of the rear drive module 1a in Figure 3 is Figure 2 exploded view of the rear drive module 1a in Figure 4 is Figure 3 Stereogram of the sensing ratchet assembly 24 in Figure 5 is Figure 3 exploded view of the sensing ratchet assembly 24 in Figure 6 is Figure 5 Stereogram of the ratchet housing 242 in Figure 7 is Figure 5 Stereogram of the ratchet base 240 in Figure 8 is Figure 5 Top view of the vehicle speed sensor 246 in Figure 9 is Figure 5 Stereogram of the reverse speed sensor 248 in Figure 10 Schematic diagram of the pulse signal in digital form Figure 11 Schematic diagram of the pulse signal in analog form.

[0041] Such as Figures 1 to 3As shown, the bicycle 1 includes a frame 10, a front wheel 12, a rear wheel 14, a rear drive module 1a and a front drive module 1b; the bicycle 1 also includes a battery (not shown) disposed in the frame 10 to supply power to the motor 14. To focus on the embodiments of the present invention, a few components are omitted from the description. The frame 10 can have a broader definition here. For example, in addition to the rigid frame body straddling between the front wheel 12 and the rear wheel 14, the frame 10 also includes a handle bar, a saddle, a front fork (not labeled) connecting the handle bar / front end of the frame body / front wheel, a seat stay (not labeled) connecting the rear end of the frame body and the rear wheel 14, and a chain stay (not labeled). The rear drive module 1a and the front drive module 1b constitute the drive system of the bicycle 1. The rear drive module 1a includes a motor 26 coaxially disposed with the rear wheel 14, a sensing ratchet set 24 and a flywheel 22; the front drive module 1b includes a chainring 16, a crank 18 and a chain 20 pivotally connected as a unit. The front wheel 14 and the rear wheel 12 are respectively rotatably disposed on the front side and the rear side of the frame 10. The chainring 16 is rotatably disposed in the middle of the frame 10 and rotates with the input of human power. The crank 18 is synchronously linked with the chainring 16. In practical applications, the two cranks 18 with pedals (not shown) are respectively disposed on opposite sides of the chainring 16, and the two cranks 18 can be linked through a bottom bracket bearing (not shown). The chain 20 is sleeved on the chainring 16 of the front drive module 1b and the flywheel 22 of the rear drive module 1a, so that the flywheel 22 is synchronously linked with the chainring 16 through the chain 20, whereby the front wheel 12 and the rear wheel 14 will also rotate simultaneously. However, depending on the number of teeth on the flywheel 22 and the chainring 16, the front wheel 12 and the rear wheel 14 may have the same or different rotational speeds. The motor 26 of the rear drive module 1a has a rear wheel shaft 260 passing through the sensing ratchet set 24 and the flywheel 22 in sequence, so that the sensing ratchet set 24 is connected between the flywheel 22 and the motor 26, and the motor 26, the sensing ratchet set 24 and the flywheel 22 are coaxial. The rear wheel shaft 260 of the motor 26 also passes through the rear wheel 14, so that the output force of the motor 26 can be directly applied to the rear wheel 14. In other words, the rear wheel 14, the motor 26, the sensing ratchet set 24 and the flywheel 22 are coaxially arranged. In addition, the flywheel 22 is formed by stacking a plurality of coaxial teeth; usually, a set of front / rear derailleur kits (not shown) is provided on the chain 20 to allow the chain 20 to move and switch between different teeth of the flywheel 22 and adjust the appropriate tightness of the chain 20 after shifting.

[0042] The bicycle 1 can have two power sources, namely human power and electric power. For the human power part, the user inputs pedaling force through the pedal / crankset 16 of the front drive module 1b. For the electric power part, the battery supplies power to drive the rear drive module 1a to apply the rotational force of the motor 26 to the rear wheel 14. In order to accurately grasp the changes in human power input and supply electric power input timely and appropriately, the bicycle 1 must be provided with multiple sensing components to monitor the rotational data of the rear drive module 1a on the rear wheel 14 and the front drive module 1b on the pedal / crankset 16 respectively.

[0043] Generally speaking, three situations can be known from the gear ratio (or speed ratio) configurations of different numbers of teeth of the crankset 16 and the freewheel 22: (1) The crankset / freewheel gear ratio is 1:1 (the number of teeth of the crankset 16 divided by the number of teeth of the freewheel 22), and the rotational speed of the rear drive module 1a and the front drive module 1b per unit time (rotational speed) is the same. (2) When the crankset / freewheel gear ratio is greater than 1, the rotational speed of the rear drive module 1a per unit time will be greater than that of the front drive module 1b. (3) When the crankset / freewheel gear ratio is less than 1, the rotational speed of the rear drive module 1a per unit time will be less than that of the front drive module 1b.

[0044] If the design logic of the power device of a non-assisted bicycle is adopted, medium-speed and high-speed riding are the main requirements, that is, the design focus is on the situations where the crankset / freewheel gear ratio in the aforementioned (1) and (2) items is greater than or equal to 1. At this time, the best installation position of the torque sensor is on the front drive module 1b, especially the bottom bracket bearing, pedal and crankset that rotate coaxially, because the function of the torque sensor is only to provide the human power output power data for the rider to refer to. At this time, the sensing components located on the front drive module 1b usually only need to have relatively low sensitivity to be usable. On the other hand, when encountering a slope or rough road surface, the speed of the bicycle 1 suddenly drops, that is, the rotational speed of the rear wheel 14 and the rear drive module 1a decreases rapidly. If relying on the sensing components installed on the front drive module 1b, or setting the torque sensor on the front drive module 1b, there is often not enough response time to detect the speed reduction problem and the sudden increase in the power assistance requirement. Therefore, in the embodiment of the present utility model, the sensing ratchet set 24 including the sensing components is set on the rear drive module 1a. The problem is that if the general sensing components used on the front drive module 1b are directly installed on the rear wheel 14, the sensing sensitivity is too low, and simply increasing the sensitivity still cannot solve the problem of torque detection of the rear wheel 14. Therefore, the sensing ratchet set 24 disclosed in the embodiment of the present utility model needs to be further adjusted in design.

[0045] As Figures 4 to 9As shown, the sensing ratchet assembly 24 includes a ratchet base 240, a ratchet housing 242, a bottom cover 244, a vehicle speed sensor 246, and a reverse speed sensor 248. The ratchet base 240 is rotatably and axially connected to the motor 26 and can rotate with the motor 26 and the rear wheel 14. The ratchet housing 242 is rotatably disposed on the ratchet base 240, and the bottom cover 244 is rotatably disposed at the end of the ratchet base 240. The vehicle speed sensor 246 is disposed between the ratchet base 240 and the bottom cover 244. The vehicle speed sensor 246 is used to sense the rotational speed of the ratchet base 240 relative to the bottom cover 244 to obtain the rotational speed (revolutions per minute, RPM) of the rear wheel 14 and thereby calculate the traveling speed of the entire bicycle 1. Preferably, the reverse speed sensor 248 is disposed between the ratchet base 240 and the ratchet housing 242. The reverse speed sensor 248 is used to sense the rotational speed of the ratchet housing 242 relative to the ratchet base 240. The vehicle speed sensor 246 can be used in conjunction with the reverse speed sensor 248 to determine the forward and reverse rotations of the chainring 16 and the freewheel 22, and estimate the pedaling frequency of the chainring 16.

[0046] As Figure 7 shown, the ratchet base 240 includes a pawl mating portion 2400, a seat bearing joint 2402, a deformation sensing portion 2404, a tension limiting portion 2406, and a load connection portion 2408. Preferably, the load connection portion 2408, the tension limiting portion 2406, the deformation sensing portion 2404, the pawl mating portion 2400, and the seat bearing joint 2402 are integrally formed. At least three pawl mounting grooves 2410 are equidistantly formed on the surface of the pawl mating portion 2400.

[0047] As Figure 6 shown, the ratchet housing 242 includes a housing body 2420 and a housing limiting portion 2422. The housing limiting portion 2422 is integrally formed at the end of the housing body 2420. When assembling the ratchet housing 242 and the ratchet base 240, the side of the load connection portion 2408 has a clearance fit with the end of the housing limiting portion 2422, so that the tension limiting portion 2406 and the housing limiting portion 2422 cooperate with each other to achieve limiting.

[0048] As Figure 5 With Figure 6As shown, a housing bearing joint 2424 is provided inside the housing body 2420. A first bearing 28 is provided in the gap between the housing body 2420 and the seat bearing joint 2402 to achieve a rotational connection. There is an interference fit between the first bearing 28 and the housing bearing joint 2424 inside the housing body 2420, and an interference fit between the first bearing 28 and the seat bearing joint 2402. Through the above settings, the rotational fit between the ratchet housing 242 and the ratchet seat 240 can be achieved. In addition, a second bearing 30 is also provided inside the housing body 2420. The second bearing 30 is located outside the seat bearing joint 2402. Specifically, there is an interference fit between the second bearing 30 and the inner wall of the housing body 2420, and the second bearing 30 is used to connect an external shaft rod.

[0049] As Figures 5 to 7 shown, a plurality of uniformly distributed pawl teeth 2426 are provided inside the ratchet housing 242, and a housing limiting portion 2422, a fixing groove 2428, pawl teeth 2426, and a housing bearing joint 2424 are sequentially arranged on the inner side of the ratchet housing 242. A pawl 250 that cooperates with the pawl teeth 2426 is provided on the ratchet seat 240. At least three pawls 250 are provided, and the number corresponds to the number of pawl mounting grooves 2410. The pawls 250 are installed in the corresponding pawl mounting grooves 2410. At least three pawls 250 can be fixedly connected through a pawl wire spring (not shown in the figure). After assembly, the positions of the pawls 250 and the pawl teeth 2426 correspond to each other to achieve mutual engagement. Since the pawls 250 and the pawl teeth 2426 are in a one-way engagement fit, a one-way torque can be applied to the ratchet seat 240 through the ratchet housing 242. Further, when a forward pedal force is applied to the ratchet housing 242, the pawl teeth 2426 and the pawls 250 on the ratchet housing 242 apply a one-way torque to the ratchet seat 240. At this time, the ratchet housing 242 and the ratchet seat 240 rotate synchronously, that is, the ratchet housing 242 and the ratchet seat 240 are relatively stationary. It should be noted that when the forward rotation speed of the ratchet seat 240 is too fast and the forward pedal speed is too slow, the ratchet housing 242 and the ratchet seat 240 will rotate relative to each other. When a reverse pedal force causes the ratchet housing 242 to rotate in the reverse direction, the ratchet housing 242 will also rotate relative to the ratchet seat 240. In this embodiment, the pawls 250 and the pawl teeth 2426 constitute a one-way clutch mechanism.

[0050] As Figure 5 with Figure 8As shown, the vehicle speed sensor 246 includes a vehicle speed sensing element 2460 and a vehicle speed sensing module 2462. The vehicle speed sensing element 2460 is fixed to the ratchet seat 240. The vehicle speed sensing module 2462 is fixed to the bottom cover 244 and is opposite to the vehicle speed sensing element 2460. In this embodiment, the vehicle speed sensing module 2462 and the vehicle speed sensing element 2460 are arranged opposite to each other along the axial direction of the sensing ratchet set 24. When the crank 18 is stepped on forward, the ratchet seat 240 will rotate relative to the bottom cover 244. When the ratchet seat 240 rotates relative to the bottom cover 244, the vehicle speed sensing module 2462 will sense the vehicle speed sensing element 2460 and output a plurality of first vehicle speed pulse signals and a plurality of second vehicle speed pulse signals. In this embodiment, the phase difference between the plurality of first vehicle speed pulse signals and the plurality of second vehicle speed pulse signals is 90 degrees.

[0051] In this embodiment, the vehicle speed sensing module 2462 may include a first vehicle speed sensor 24620 and a second vehicle speed sensor 24622, wherein the first vehicle speed sensor 24620 and the second vehicle speed sensor 24622 are arranged in a straight line along the radial direction of the vehicle speed sensing module 2462. In addition, the vehicle speed sensing element 2460 may include a plurality of first vehicle speed target elements 24600 and a plurality of second vehicle speed target elements 24602, wherein the plurality of first vehicle speed target elements 24600 and the plurality of second vehicle speed target elements 24602 are arranged in two adjacent rings and are offset from each other. When the ratchet seat 240 rotates relative to the bottom cover 244, the first vehicle speed sensor 24620 senses the plurality of first vehicle speed target elements 24600 and outputs a plurality of first vehicle speed pulse signals, and the second vehicle speed sensor 24622 senses the plurality of second vehicle speed target elements 24602 and outputs a plurality of second vehicle speed pulse signals. The first vehicle speed pulse signals and the second vehicle speed pulse signals can be used to obtain the rotational speed of the rear wheel 14 and the vehicle speed of the bicycle 1. In a preferred embodiment, the vehicle speed sensing module 2462 may further include a position sensor 24624, wherein the first vehicle speed sensor 24620, the second vehicle speed sensor 24622 and the position sensor 24624 are arranged in a straight line along the radial direction of the vehicle speed sensing module 2462. In addition, the vehicle speed sensing element 2460 may further include a position target element 24604. When the sprocket 22 rotates one circle, the vehicle speed sensing element 2460 rotates one circle accordingly, and the position sensor 24624 senses the position target element 24604 and outputs a position pulse signal. The position pulse signal can be used to determine the absolute position of the rotating shaft.

[0052] In one embodiment, the first vehicle speed sensor 24620, the second vehicle speed sensor 24622, and the position sensor 24624 may be magnetic sensors, and the first vehicle speed target element 24600, the second vehicle speed target element 24602, and the position target element 24604 may be formed by magnetizing at corresponding positions. In another embodiment, the first vehicle speed sensor 24620, the second vehicle speed sensor 24622, and the position sensor 24624 may be optical sensors, and the first vehicle speed target element 24600, the second vehicle speed target element 24602, and the position target element 24604 may be formed by etching gratings at corresponding positions. In another embodiment, the first vehicle speed sensor 24620, the second vehicle speed sensor 24622, and the position sensor 24624 may be capacitive sensors, and the first vehicle speed target element 24600, the second vehicle speed target element 24602, and the position target element 24604 may be formed by arranging metal wires at corresponding positions.

[0053] In one embodiment, the first vehicle speed pulse signal, the second vehicle speed pulse signal, and the position pulse signal may be digital signals, such as Figure 10 shown. In another embodiment, the first vehicle speed pulse signal, the second vehicle speed pulse signal, and the position pulse signal may be analog signals, such as Figure 11 shown.

[0054] In this embodiment, when the gear ratio between the flywheel 22 and the toothed disc 16 is between 1 and 0.5, and the toothed disc 22 rotates one circle, the vehicle speed sensing element 2460 rotates one circle accordingly, and the number of pulse signals output by the vehicle speed sensor 246 is between 24 and 150 (that is, when the ratchet seat 240 rotates one circle relative to the bottom cover 244, the number of pulse signals output by the vehicle speed sensor 246 is between 24 and 150). In other words, the percentage of the gear ratio to the number of pulse signals is between 0.33% and 4.17%. Thereby, when the gear ratio is less than 1, the number of pulse signals output by the vehicle speed sensor 246 can be effectively increased, and thus the rear-wheel transmission sensitivity of the bicycle 1 can be improved.

[0055] Such as Figure 5 and Figure 9As shown, the reverse rotation speed sensor 248 may include a reverse rotation speed sensing element 2480 and a reverse rotation speed sensing module 2482. The reverse rotation speed sensing element 2480 is fixed to the ratchet housing 242. The reverse rotation speed sensing module 2482 is fixed to the ratchet seat 240 and is opposite to the reverse rotation speed sensing element 2480. In this embodiment, the reverse rotation speed sensing module 2482 and the reverse rotation speed sensing element 2480 are arranged opposite to each other along the radial direction of the sensing ratchet set 24. When the crank 18 is reverse pedaled, the ratchet housing 242 will rotate relative to the ratchet seat 240. When the ratchet housing 242 rotates relative to the ratchet seat 240, the reverse rotation speed sensing module 2482 will sense the reverse rotation speed sensing element 2480 and output a plurality of first reverse rotation speed pulse signals and a plurality of second reverse rotation speed pulse signals. In this embodiment, the phase difference between the plurality of first reverse rotation speed pulse signals and the plurality of second reverse rotation speed pulse signals is 90 degrees.

[0056] In this embodiment, the reverse rotation speed sensing module 2482 may include a first reverse rotation speed sensor 24820 and a second reverse rotation speed sensor 24822, wherein the first reverse rotation speed sensor 24820 and the second reverse rotation speed sensor 24822 are linearly arranged along the axial direction of the reverse rotation speed sensing module 2482. In addition, the reverse rotation speed sensing element 2480 includes a plurality of first reverse rotation speed target elements 24800 and a plurality of second reverse rotation speed target elements 24802, wherein the plurality of first reverse rotation speed target elements 24800 and the plurality of second reverse rotation speed target elements 24802 are arranged in two adjacent rings and are offset from each other. When the ratchet housing 242 rotates relative to the ratchet seat 240, the first reverse rotation speed sensor 24820 senses the plurality of first reverse rotation speed target elements 24800 and outputs a plurality of first reverse rotation speed pulse signals, and the second reverse rotation speed sensor 24822 senses the plurality of second reverse rotation speed target elements 24802 and outputs a plurality of second reverse rotation speed pulse signals. The first reverse rotation speed pulse signals and the second reverse rotation speed pulse signals can be used in combination with the above-mentioned first vehicle speed pulse signals and second vehicle speed pulse signals to determine the forward and reverse rotations of the chainring 16 and the flywheel 22, and estimate the pedaling frequency of the chainring 16. In this embodiment, the reverse rotation speed sensing module 2482 may further include a position sensor 24824, wherein the first reverse rotation speed sensor 24820, the second reverse rotation speed sensor 24822 and the position sensor 24824 are linearly arranged along the axial direction of the reverse rotation speed sensing module 2482. In addition, the reverse rotation speed sensing element 2480 may further include a position target element 24804. When the chainring 22 rotates one circle, the vehicle speed sensing element 2460 rotates one circle accordingly, and the position sensor 24824 senses the position target element 24804 and outputs a position pulse signal. The position pulse signal can be used to determine the absolute position of the rotating shaft.

[0057] In one embodiment, the first reverse rotation speed sensor 24820, the second reverse rotation speed sensor 24822, and the position sensor 24824 can be magnetic sensors, and the first reverse rotation speed target element 24800, the second reverse rotation speed target element 24802, and the position target element 24804 can be formed by magnetizing at corresponding positions. In another embodiment, the first reverse rotation speed sensor 24820, the second reverse rotation speed sensor 24822, and the position sensor 24824 can be optical sensors, and the first reverse rotation speed target element 24800, the second reverse rotation speed target element 24802, and the position target element 24804 can be formed by etching gratings at corresponding positions. In another embodiment, the first reverse rotation speed sensor 24820, the second reverse rotation speed sensor 24822, and the position sensor 24824 can be capacitive sensors, and the first reverse rotation speed target element 24800, the second reverse rotation speed target element 24802, and the position target element 24804 can be formed by arranging metal wires at corresponding positions.

[0058] In one embodiment, the first reverse rotation speed pulse signal, the second reverse rotation speed pulse signal, and the position pulse signal can be digital signals. In another embodiment, the first reverse rotation speed pulse signal, the second reverse rotation speed pulse signal, and the position pulse signal can be analog signals.

[0059] As Figure 8 and Figure 9 shown, the sensing ratchet assembly 24 may further include a processor 252 and a torque measurement module 254. The processor 252 can be disposed in the vehicle speed sensing module 2462, and the torque measurement module 254 can be disposed in the reverse rotation speed sensing module 2482. The torque measurement module 254 is used to measure the torque applied to the sensing ratchet assembly 24, so that the processor 252 can obtain the pedaling power according to this torque. Further, the torque measurement module 254 can be disposed on the ratchet seat 240 along with the reverse rotation speed sensing module 2482. The torque measurement module 254 is used to sense the magnitude of the external force-induced distortion to obtain a signal of the distortion caused by the external force. The torque measurement module 254 can be fixed on the surface of the deformation sensing portion 2404. The external force applies torque to the ratchet housing 242 through the flywheel 22, and through the mutual cooperation of the ratchet teeth 2426 and the pawl 250, and then applies torque to the load connection portion 2408 through the deformation sensing portion 2404. In the above process, the torque measurement module 254 will generate a deformation corresponding to the torque magnitude to obtain a signal of the distortion caused by the external force. The processor 252 can control the motor 26 according to the magnitude of the signal of the distortion caused by the external force to achieve corresponding torque and speed regulation. The torque measurement module 254 can measure the torque through strain gauges. Then, the processor 252 can multiply the torque by the rear wheel speed to obtain the pedaling power.

[0060] Please refer to Figure 12 , Figure 12It is a top view of the vehicle speed sensor 246' according to another embodiment of the present utility model.

[0061] As Figure 12 shown, the vehicle speed sensing module 2462 of the vehicle speed sensor 246' includes a first vehicle speed sensor 24620, a second vehicle speed sensor 24622, and a position sensor 24624. Among them, the first vehicle speed sensor 24620 and the second vehicle speed sensor 24622 are arranged at an angular interval of 90 degrees, and the first vehicle speed sensor 24620 and the position sensor 24624 are arranged in a straight line along the radial direction of the vehicle speed sensing module 2462. In addition, the vehicle speed sensing element 2460 of the vehicle speed sensor 246' includes a plurality of vehicle speed target elements 24606 and a position target element 24604, and the plurality of vehicle speed target elements 24606 are arranged in a ring shape.

[0062] Figure 5 The vehicle speed sensor 246 shown can Figure 12 be replaced by the vehicle speed sensor 246' shown. When the ratchet seat 240 rotates relative to the bottom cover 244, the first vehicle speed sensor 24620 will sense a plurality of vehicle speed target elements 24606 and output a plurality of first vehicle speed pulse signals, and the second vehicle speed sensor 24622 will sense a plurality of vehicle speed target elements 24606 and output a plurality of second vehicle speed pulse signals. In addition, when the gear disk 22 rotates one circle, the vehicle speed sensing element 2460 rotates one circle accordingly, and the position sensor 24624 will sense the position target element 24604 and output a position pulse signal. It should be noted that the functions of the first vehicle speed pulse signal, the second vehicle speed pulse signal, and the position pulse signal are as described above, and will not be elaborated here.

[0063] Please refer to Figure 13 , Figure 13 It is a perspective view of the reverse speed sensor 248' according to another embodiment of the present utility model.

[0064] As Figure 13 shown, the reverse speed sensing module 2482 of the reverse speed sensor 248' includes a first reverse speed sensor 24820, a second reverse speed sensor 24822, and a position sensor 24824. Among them, the first reverse speed sensor 24820 and the second reverse speed sensor 24822 are arranged at an angular interval of 90 degrees, and the first reverse speed sensor 24820 and the position sensor 24824 are arranged in a straight line along the axial direction of the reverse speed sensing module 2482. In addition, the reverse speed sensing element 2480 of the reverse speed sensor 248' includes a plurality of reverse speed target elements 24806 and a position target element 24804, and the plurality of reverse speed target elements 24806 are arranged in a ring shape.

[0065] Figure 5 The reverse rotation speed sensor 248 shown can Figure 13 be replaced by the reverse rotation speed sensor 248'. When the ratchet housing 242 rotates relative to the ratchet seat 240, the first reverse rotation speed sensor 24820 will sense a plurality of reverse rotation speed target elements 24806 and output a plurality of first reverse rotation speed pulse signals, and the second reverse rotation speed sensor 24822 will sense a plurality of reverse rotation speed target elements 24806 and output a plurality of second reverse rotation speed pulse signals. In addition, when the toothed disc 22 rotates one circle, the vehicle speed sensing element 2460 rotates one circle accordingly, and the position sensor 24824 will sense the position target element 24804 and output a position pulse signal. It should be noted that the functions of the first reverse rotation speed pulse signal, the second reverse rotation speed pulse signal, and the position pulse signal are as described above, and will not be elaborated here.

[0066] In summary, the sensing ratchet of the present utility model is assembled on the flywheel of the rear transmission assembly. When the gear ratio between the flywheel and the toothed disc is between 1 and 0.5, and the toothed disc 22 rotates one circle, the number of pulse signals output by the vehicle speed sensor is between 24 and 150. Thereby, when the gear ratio is less than 1, the number of pulse signals output by the vehicle speed sensor can be effectively increased, and further the rear wheel transmission sensitivity of the assisted bicycle can be optimized. In an embodiment, the present utility model can make the phase difference between the first vehicle speed pulse signal and the second vehicle speed pulse signal output by the vehicle speed sensing module be 90 degrees to adjust the number of pulse signals output by the vehicle speed sensor to the most appropriate amount. In addition, although the bicycle in the foregoing embodiment is provided with a power source and a motor, the drive system and the sensing ratchet set of this case can also be applied to a general bicycle without auxiliary power.

[0067] The present utility model has been described by the above related embodiments. However, the above embodiments are only examples for implementing the present utility model. It must be pointed out that the disclosed embodiments do not limit the scope of the present utility model. On the contrary, modifications and refinements made without departing from the spirit and scope of the present utility model fall within the scope of patent protection of the present utility model.

Claims

1. A bicycle drive system, characterized in that: Include: The toothed disc rotates with human input; A chain connecting the toothed discs; A flywheel, comprising a plurality of gears coaxially stacked on the rear wheel shaft, the flywheel being connected to the chain via one of the plurality of gears, so that the flywheel is driven by the chain and linked to the sprocket; and A sensing ratchet assembly is axially connected to one side of the flywheel, and the sensing ratchet assembly comprises: ratchet seat; A ratchet housing is rotatably disposed on the ratchet seat; A bottom cover rotatably disposed on an end of the ratchet seat; and A vehicle speed sensor is disposed between the ratchet base and the bottom cover, and is used to sense the speed of the ratchet base relative to the bottom cover; When the gear ratio of the flywheel to the sprocket is adjusted to between 1 and 0.5, the number of pulse signals output by the vehicle speed sensor is between 24 and 150 when the sprocket rotates one circle.

2. The bicycle drive system according to claim 1, characterized in that: The vehicle speed sensor includes: A vehicle speed sensing element is fixed to the ratchet seat; and A vehicle speed sensing module is fixed to the bottom cover and is opposite to the vehicle speed sensing element; When the ratchet seat rotates relative to the bottom cover, the vehicle speed sensing module senses the vehicle speed sensing element and outputs multiple first vehicle speed pulse signals and multiple second vehicle speed pulse signals. The phase difference between the multiple first vehicle speed pulse signals and the multiple second vehicle speed pulse signals is 90 degrees.

3. The bicycle drive system according to claim 2, characterized in that: The vehicle speed sensing module includes a first vehicle speed sensor and a second vehicle speed sensor. The first vehicle speed sensor and the second vehicle speed sensor are arranged in a radial straight line along the vehicle speed sensing module. The vehicle speed sensing element includes a plurality of first vehicle speed target elements and a plurality of second vehicle speed target elements. The plurality of first vehicle speed target elements and the plurality of second vehicle speed target elements are arranged in two adjacent rings and are staggered with each other. The first vehicle speed sensor senses the plurality of first vehicle speed target elements and outputs the plurality of first vehicle speed pulse signals. The second vehicle speed sensor senses the plurality of second vehicle speed target elements and outputs the plurality of second vehicle speed pulse signals.

4. The bicycle drive system according to claim 3, characterized in that: The vehicle speed sensing module also includes a position sensor. The first vehicle speed sensor, the second vehicle speed sensor and the position sensor are arranged in a radial straight line along the vehicle speed sensing module. The vehicle speed sensing element includes a position target element. When the gear wheel rotates one circle, the position sensor senses the position target element and outputs a position pulse signal.

5. The bicycle drive system according to claim 2, wherein: The vehicle speed sensing module includes a first vehicle speed sensor and a second vehicle speed sensor. The first vehicle speed sensor and the second vehicle speed sensor are arranged at an arc angle of 90 degrees. The vehicle speed sensing element includes a plurality of vehicle speed target elements. The plurality of vehicle speed target elements are arranged in a ring. The first vehicle speed sensor senses the plurality of vehicle speed target elements and outputs the plurality of first vehicle speed pulse signals. The second vehicle speed sensor senses the plurality of vehicle speed target elements and outputs the plurality of second vehicle speed pulse signals.

6. The bicycle drive system according to claim 5, characterized in that: The vehicle speed sensing module also includes a position sensor. The first vehicle speed sensor and the position sensor are arranged in a radial straight line along the vehicle speed sensing module. The vehicle speed sensing element includes a position target element. When the gear wheel rotates one circle, the position sensor senses the position target element and outputs a position pulse signal.

7. The bicycle drive system according to claim 1, wherein: The sensing ratchet assembly further includes a reverse speed sensor, which is disposed between the ratchet seat and the ratchet shell. The reverse speed sensor is used to sense the speed of the ratchet shell relative to the ratchet seat. The reverse speed sensor includes: A reverse speed sensing element fixed to the ratchet housing; and A reverse speed sensing module is fixed to the ratchet seat and is opposite to the reverse speed sensing element; When the ratchet housing rotates relative to the ratchet seat, the reverse speed sensing module senses the reverse speed sensing element and outputs a plurality of first reverse speed pulse signals and a plurality of second reverse speed pulse signals, and the phase difference between the plurality of first reverse speed pulse signals and the plurality of second reverse speed pulse signals is 90 degrees.

8. The bicycle drive system according to claim 7, wherein: The reverse rotation speed sensing module includes a first reverse rotation speed sensor and a second reverse rotation speed sensor, the first reverse rotation speed sensor and the second reverse rotation speed sensor are arranged in a straight line along the axial direction of the reverse rotation speed sensing module, the reverse rotation speed sensing element includes a plurality of first reverse rotation speed target elements and a plurality of second reverse rotation speed target elements, the plurality of first reverse rotation speed target elements and the plurality of second reverse rotation speed target elements are arranged in two adjacent rings and are staggered with each other, the first reverse rotation speed sensor senses the plurality of first reverse rotation speed target elements and outputs the plurality of first reverse rotation speed pulse signals, and the second reverse rotation speed sensor senses the plurality of second reverse rotation speed target elements and outputs the plurality of second reverse rotation speed pulse signals.

9. The bicycle drive system according to claim 8, wherein: The reverse speed sensing module also includes a position sensor. The first reverse speed sensor, the second reverse speed sensor and the position sensor are arranged in a straight line along the axial direction of the reverse speed sensing module. The reverse speed sensing element includes a position target element. When the gear rotates one circle, the position sensor senses the position target element and outputs a position pulse signal.

10. The bicycle drive system according to claim 7, wherein: The reverse speed sensing module includes a first reverse speed sensor and a second reverse speed sensor, the first reverse speed sensor and the second reverse speed sensor are arranged at an arc angle of 90 degrees, the reverse speed sensing element includes a plurality of reverse speed target elements, the plurality of reverse speed target elements are arranged in a ring, the first reverse speed sensor senses the plurality of reverse speed target elements and outputs the plurality of first reverse speed pulse signals, the second reverse speed sensor senses the plurality of reverse speed target elements and outputs the plurality of second reverse speed pulse signals.

11. The bicycle drive system according to claim 10, wherein: The reverse speed sensing module also includes a position sensor. The first reverse speed sensor and the position sensor are arranged in a straight line along the axial direction of the reverse speed sensing module. The reverse speed sensing element includes a position target element. When the gear rotates one circle, the position sensor senses the position target element and outputs a position pulse signal.

12. The bicycle drive system according to claim 1, wherein: The sensing ratchet assembly further comprises a processor and a torque force measurement module, wherein the torque force measurement module is used to measure the torque applied to the sensing ratchet assembly, and the processor obtains the pedaling power according to the torque.

13. A bicycle drive system, characterized in that: Include: The toothed disc rotates with human input; A chain connecting the toothed discs; A flywheel, comprising a plurality of gears coaxially stacked on the rear wheel shaft, the flywheel being connected to the chain via one of the plurality of gears, so that the flywheel is driven by the chain and linked to the sprocket; and A sensing ratchet assembly is axially connected to one side of the flywheel, and the sensing ratchet assembly comprises: ratchet seat; A ratchet housing is rotatably disposed on the ratchet seat; A bottom cover rotatably disposed on an end of the ratchet seat; and A vehicle speed sensor is disposed between the ratchet base and the bottom cover, and is used to sense the speed of the ratchet base relative to the bottom cover; The percentage of the gear ratio between the flywheel and the gear plate and the number of pulse signals output by the vehicle speed sensor is between 0.33% and 4.17%.

14. A sensing ratchet assembly, characterized in that: Include: ratchet seat; A ratchet housing is rotatably disposed on the ratchet seat; A bottom cover rotatably disposed on an end of the ratchet seat; and The vehicle speed sensor is disposed between the ratchet base and the bottom cover. The vehicle speed sensor is used to sense the speed of the ratchet base relative to the bottom cover. The vehicle speed sensor includes: A vehicle speed sensing element is fixed to the ratchet seat; and A vehicle speed sensing module is fixed to the bottom cover and is opposite to the vehicle speed sensing element; When the ratchet seat rotates relative to the bottom cover, the vehicle speed sensing module senses the vehicle speed sensing element and outputs multiple first vehicle speed pulse signals and multiple second vehicle speed pulse signals. The phase difference between the multiple first vehicle speed pulse signals and the multiple second vehicle speed pulse signals is 90 degrees.

15. The sensing ratchet assembly according to claim 14, characterized in that: When the ratchet seat rotates one circle relative to the bottom cover, the number of pulse signals output by the vehicle speed sensor is between 24 and 150.

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