Displacement sensing torque sensor
By designing an external displacement-induced torque sensor, the problems of difficulty in repairing and inconvenient modification of the hub motor sensor are solved, convenient installation of the sensor and accurate collection of torque signals are achieved, and maintenance and modification costs are reduced.
Patent Information
- Application Number
- CN202422825747.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-20
- Publication Date
- 2025-08-22
- Estimated Expiration
- 2034-11-20
AI Technical Summary
The torque acquisition method of existing hub motors is usually installed in the motor, which is difficult to repair and inconvenient to modify, especially the modification of sensorless motors.
A displacement-induced torque sensor is designed, including a driven ring, an active ring, an adjustment ring, a magnetic ring, a second elastic member and a tower base. Through the Hall sensor, the magnetic ring and the adjustment ring are combined with the axial displacement, torque signals are collected, and the sensor is externally structured, which is convenient for modification and maintenance.
The external installation of the sensor is realized, which facilitates subsequent modification and maintenance, reduces costs, and improves the accuracy and protection of torque acquisition through the combination of the inclined surfaces of the drive teeth and the drive groove to prevent signal errors.
Smart Images
Figure CN223259107U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of motors, in particular to a displacement induction torque sensor. Background Art
[0002] Electric motors are one of the most common power devices. Over a century of development, they have evolved into a variety of different types and structures, becoming one of the most important devices in daily production and life. In-wheel hub motors, due to their simple structure, reliable performance, and low cost, are widely used in vehicle propulsion, especially in commuter vehicles such as electric vehicles and electric-assisted bicycles. However, many existing in-wheel hub motors use torque sensors to collect torque. These sensors are often installed inside the motor, making maintenance very cumbersome. Furthermore, this method is not convenient for retrofitting sensorless motors. Utility Model Content
[0003] In view of the defects of the above-mentioned prior art, the main purpose of the present invention is to overcome the shortcomings of the prior art, and discloses a displacement sensing torque sensor, comprising a coaxially arranged driven ring, an active ring, an adjusting ring, a magnetic ring, a second elastic member and a freehub base, wherein the driven ring is connected to the hub shell, the active ring is connected to the driven ring, the freehub base is rotatably connected to the shaft through a bearing, the adjusting ring is axially slidably connected to the freehub base, the second elastic member connects the adjusting ring and the freehub base, and the second elastic member is used to provide axial thrust for the adjusting ring; the magnetic ring is arranged in the adjusting ring, and a Hall sensor is installed on the shaft, and the magnetic ring and the Hall sensor cooperate to collect the axial displacement distance of the adjusting ring;
[0004] One end of the active ring is concavely provided with at least one driving groove around its axial direction, and one end of the adjusting ring is convexly provided with a driving tooth, a first driving part and a first limiting part are arranged in the driving groove, a second driving part and a second limiting part are arranged on the driving tooth, the first driving part and the second driving part are mutually matched inclined surfaces, the first limiting part and the second limiting part are mutually matched planes, and the planes are parallel to the axis.
[0005] Furthermore, the driven ring and the driving ring are connected in a one-way driving manner.
[0006] Furthermore, the contact ends of the driven ring and the active ring are provided with mutually cooperating one-way teeth, the active ring is connected to the tower base via a first elastic member, and the first elastic member is used to provide the active ring with a force to move axially toward the driven ring.
[0007] Furthermore, a clearance is axially provided between the driving teeth and the driving groove for avoiding separation of the active ring and the driven ring.
[0008] Furthermore, the first elastic member is a spring.
[0009] Furthermore, the second elastic member is a spring or a leaf spring.
[0010] Furthermore, at least one key is arranged around the outer circumference of the adjustment ring, and a key slot is arranged on the inner circumference of the tower base to cooperate with the key, and the key is slidably engaged with the key slot.
[0011] Furthermore, it also includes a concentric ring, which is coaxially arranged in the adjustment ring, and the active ring is axially slidably arranged on the concentric ring, and the concentric ring is used to guide the axial movement of the active ring.
[0012] Furthermore, the concentric ring is tightly fitted with the adjustment ring.
[0013] Beneficial effects achieved by this utility model:
[0014] This new design features a simple structure and externally located sensors, facilitating subsequent modification and sensor maintenance. The drive teeth and drive slots utilize beveled surfaces to drive the wheel hub rotation, while the adjustment ring simultaneously drives the axial displacement of the magnetic ring for torque acquisition. This simple structure significantly reduces costs. Limiting elements are incorporated within the drive teeth and drive slots. When excessive torque is input from the tower base, these elements act as a limiter and protect against excessive magnetic ring displacement, which could lead to signal acquisition errors and affect the controller's torque determination. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 This is a schematic diagram of the three-dimensional structure of a displacement sensing torque sensor of the present utility model;
[0016] Figure 2 for Figure 1 Right view;
[0017] Figure 3 for Figure 2 AA section view;
[0018] Figure 4 This is a three-dimensional exploded view of a displacement sensing torque sensor of the present utility model;
[0019] Figure 5 This is a front exploded view of a displacement sensing torque sensor of the present utility model;
[0020] The reference numerals are as follows:
[0021] 1. Driven ring, 2. Driving ring, 3. Adjusting ring, 4. Magnetic ring, 5. Second elastic member, 6. Tower base, 7. One-way tooth, 8. First elastic member, 9. Avoidance gap, 10. Concentric ring, 11. Support ring, 21. Driving groove, 31. Driving tooth, 32. Key, 61. Keyway, 211. First driving part, 212. First limiting part, 311. Second driving part, 312. Second limiting part. DETAILED DESCRIPTION
[0022] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.
[0023] A displacement sensing torque sensor, such as Figure 1-Figure 5 As shown, the system comprises a coaxially arranged driven ring 1, an active ring 2, an adjustment ring 3, a magnetic ring 4, a second elastic member 5, and a freehub base 6. The driven wheel 1 is connected to the motor hub. The active ring 2 is connected to the driven ring 1, the freehub base 6 is rotatably connected to the shaft via a bearing, the adjustment ring 3 is axially slidably connected to the freehub base 6, and the second elastic member 5 connects the adjustment ring 3 and the freehub base 6, providing axial thrust to the adjustment ring 3. The magnetic ring 4 is disposed within the adjustment ring, and a Hall effect sensor is mounted on the shaft. The magnetic ring 4 and the Hall effect sensor cooperate to detect the axial displacement of the adjustment ring 3. During operation, the sprocket on the freehub base 6 drives the adjustment ring 6, which in turn drives the active ring 2 to rotate. The active ring 2 then drives the driven ring 1 to rotate the hub. The magnetic ring 4 cooperates with the Hall effect sensor to detect the axial displacement of the magnetic ring 4.
[0024] Specifically, at least one driving groove 21 is recessed around the axial direction of one end of the active ring 2, and a driving tooth 31 is protruded from one end of the adjustment ring 3. A first driving portion 211 and a first limiting portion 212 are provided in the driving groove 21, and a second driving portion 311 and a second limiting portion 312 are provided on the driving tooth 31. The first driving portion 211 and the second driving portion 311 are mutually matching inclined surfaces, that is, the first driving portion 211 and the second driving portion 311 respectively have an angle with the axis. The first limiting portion 212 and the second limiting portion 312 are mutually matching planes, and the planes are parallel to the axis. Through the above structure, when the tower base 6 drives the adjustment ring 3 to rotate synchronously, the second driving portion 311 cooperates with the first driving portion 211 to generate a force that drives the adjustment ring 3 to move axially toward the second elastic member 5, and a force that drives the active ring 2 to rotate. During this process, the torque input through the tower base 6 will cause the adjustment ring 3 to overcome the second elastic member 5 to perform axial displacement, and the displacement distance of the magnetic ring 4 is collected by the Hall sensor to realize torque collection, which is then transmitted to the controller to control the motor torque output and realize bicycle power assistance.
[0025] In the above embodiment, if Figure 1-Figure 5 As shown, the number of drive slots 21 is set to six, and correspondingly, the number of drive teeth 31 is also set to six; the drive slots 21 can be arranged at equal intervals or unevenly, and the positions of the drive teeth 31 correspond to the positions of the drive slots 21. In addition, the number of drive slots 21 and drive teeth 31 is not limited to six, and can be increased or decreased according to actual needs.
[0026] In one embodiment, if Figure 1-Figure 5 As shown, the driven ring 1 and the driving ring 2 are connected in a one-way drive manner. That is, when the tower base 6 controls the rotation of the driving ring 2, the driving ring 2 connects with the driven ring 1, achieving power transmission. However, when the speed of the driven ring 1 is greater than that of the driving ring 2, the driven ring 1 cannot drive the driving ring 2 to rotate synchronously.
[0027] In the above embodiment, if Figure 1-Figure 5 As shown, the contact ends of the driven ring 1 and the driving ring 2 are provided with mutually cooperating one-way teeth 7. The driving ring 2 is connected to the freewheel base 6 via a first elastic member 8. The first elastic member 8 provides a force for the driving ring 2 to move axially toward the driven ring 1. This allows the driving ring 2 to adhere tightly to the driven ring 1. When the speed of the driving ring 2 is greater than that of the driven ring 1, power transmission can be achieved between the driving ring 2 and the driven ring 1.
[0028] In the above embodiment, if Figure 1-Figure 5 As shown, an axial clearance gap 9 is provided between the driving teeth 31 and the driving grooves 21 for use when the active ring 2 is separated from the driven ring 1. The clearance gap 9 is used to overcome the axial displacement of the active ring 2 when the driven ring 1 is separated from the active ring 2, thereby avoiding affecting the adjustment ring 3 and causing erroneous displacement of the magnetic ring 4.
[0029] In the above embodiment, if Figure 1-Figure 5 As shown, the first elastic member 8 is a spring.
[0030] In the above embodiment, if Figure 1-Figure 5 As shown, the second elastic member 5 is a spring or a reed.
[0031] In one embodiment, if Figure 1-Figure 5 As shown, at least one key 32 is disposed around the outer circumference of the adjustment ring 3, and a keyway 61 is disposed on the inner circumference of the freewheel base 6 to engage with the key 32. The key 32 slides within the keyway 61, thereby achieving an axial sliding connection between the adjustment ring 3 and the freewheel base 6. The number of keys 32 corresponds to the number of keyways 61, and the number of keys 32 and keyways 61 is not limited to one; two or more keys 32 and keyways 61 may be provided. In one embodiment, 24 keys 32 are provided at equal intervals.
[0032] In one embodiment, if Figure 1-Figure 5As shown, the system further includes a concentric ring 10, which is coaxially arranged inside the adjustment ring 3. The active ring 2 is axially slidably arranged on the concentric ring 10, and the concentric ring 10 guides the axial movement of the active ring 2. This ensures that the active ring 2 is concentric with the adjustment ring 3, thereby improving the accuracy of torque signal acquisition.
[0033] In the above embodiment, if Figure 1-Figure 5 As shown, the concentric ring 10 is tightly fitted with the adjusting ring 3. That is, the connecting portion of the concentric ring 10 and the adjusting ring 3 is installed in an interference fit manner.
[0034] In one embodiment, if Figure 1-Figure 5 As shown, in order to ensure that the tower base 6 is concentric with the shaft, two bearings are provided.
[0035] In one embodiment, if Figure 1-Figure 5 As shown, a support ring 11 is installed in the tower base 6, and the support ring 11 bears the reaction force of the second elastic member 5. The support ring 11 and the tower base 6 are tightly fitted.
[0036] When the utility model is used, Figure 1-Figure 5 As shown, the driven ring 1 is installed concentrically with the hub motor, a sprocket is installed on the tower base 6, the sprocket is driven by the chain to drive the tower base 6 to rotate, the tower base 6 drives the adjusting ring 3 to rotate, the adjusting ring 3 and the active ring 2 cooperate through the driving teeth 31 and the driving groove 21, the displacement distance of the magnetic ring 4 is collected by the Hall sensor, and at the same time the active ring 2 is engaged with the one-way teeth 7 of the driven ring 1, and the wheel hub is driven to rotate through the driven ring 1. The controller receives the torque signal of the Hall sensor and controls the torque output of the hub motor to help drive the wheel hub to rotate.
[0037] The above are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Without departing from the spirit and scope of the present invention, modifications or equivalent replacements of the present invention should be included in the scope of protection of the claims of the present invention.
Claims
1. A displacement sensing torque sensor, characterized in that: The invention comprises a coaxially arranged driven ring, an active ring, an adjusting ring, a magnetic ring, a second elastic member and a freehub base, wherein the driven ring is connected to the hub shell, the active ring is connected to the driven ring, the freehub base is rotatably connected to the shaft via a bearing, the adjusting ring is axially slidably connected to the freehub base, the second elastic member connects the adjusting ring and the freehub base, and the second elastic member is used to provide an axial thrust for the adjusting ring; the magnetic ring is arranged inside the adjusting ring, and a Hall sensor is mounted on the shaft, and the magnetic ring and the Hall sensor cooperate to collect the axial displacement distance of the adjusting ring; One end of the active ring is concavely provided with at least one driving groove around its axial direction, and one end of the adjusting ring is convexly provided with a driving tooth, a first driving part and a first limiting part are arranged in the driving groove, a second driving part and a second limiting part are arranged on the driving tooth, the first driving part and the second driving part are mutually matched inclined surfaces, the first limiting part and the second limiting part are mutually matched planes, and the planes are parallel to the axis.
2. A displacement sensing torque sensor according to claim 1, characterized in that: The driven ring and the active ring are connected in a one-way driving manner.
3. A displacement sensing torque sensor according to claim 2, characterized in that: The contact ends of the driven ring and the active ring are provided with mutually cooperating one-way teeth, the active ring is connected to the tower base through a first elastic member, and the first elastic member is used to provide the active ring with a force for axial movement toward the driven ring.
4. A displacement sensing torque sensor according to any one of claims 2 and 3, characterized in that: A clearance is axially provided between the driving teeth and the driving groove for avoiding the separation of the active ring and the driven ring.
5. The displacement sensing torque sensor according to claim 3, characterized in that: The first elastic member is a spring.
6. The displacement sensing torque sensor according to claim 1, characterized in that: The second elastic member is a spring or a reed.
7. The displacement sensing torque sensor according to claim 1, characterized in that: At least one key is arranged around the outer periphery of the adjusting ring, and a key slot matched with the key is arranged on the inner periphery of the tower base, and the key is slidably matched with the key slot.
8. The displacement sensing torque sensor according to claim 1, characterized in that: It also includes a concentric ring, which is coaxially arranged in the adjusting ring. The active ring is axially slidably arranged on the concentric ring, and the concentric ring is used to guide the axial movement of the active ring.
9. The displacement sensing torque sensor according to claim 8, characterized in that: The concentric ring is tightly fitted with the adjusting ring.