Injection molding gear device

Abstract

The utility model discloses an injection molding gear device, and aims to solve the problems that the position of a gear in a traditional injection molding gear device is unstable, and the stability of the whole structure is influenced along with the temperature change. The injection molding gear device comprises a gear assembly and a main shaft, wherein the gear assembly is sleeved on the main shaft and is connected with the main shaft; the gear assembly comprises a gear structure and an injection molding limiting part, the gear structure is fixedly connected with the injection molding limiting part, a deformation groove set and an overflow groove are formed in the main shaft, the gear structure is arranged on the outer side of the deformation groove set in a sleeving mode, the injection molding limiting part is arranged on the outer side of the overflow groove, and a boss is arranged on the inner side of the injection molding limiting part and matched with the overflow groove. And the boss is arranged in the overflow groove. The overflow groove and the boss of the injection molding limiting part form the embedded structure, and compared with traditional single interference fit or key connection, the embedded structure can bear larger loads; the main shaft is provided with the deformation groove set, the gear structure is arranged on the outer side of the deformation groove set in a sleeving mode, and stress concentration is avoided.

Description

Technical Field

[0001] This utility model relates to the field of gear technology, and in particular to an injection-molded gear device. Background Technology

[0002] Traditional metal gears suffer from high vibration, noise, and lubrication requirements. While plastic gears offer advantages such as vibration reduction, noise reduction, and self-lubrication, they also suffer from insufficient toughness and susceptibility to deformation. To balance performance, metal-polymer composite gears have been proposed. By manufacturing metal skeleton inserts and combining them with injection molding processes, shrinkage cavities and deformation can be suppressed.

[0003] Currently, injection molding technology is developing rapidly in three aspects: material innovation, process optimization, and equipment intelligence. However, it still has shortcomings in dimensional accuracy, mechanical properties, appearance, and assembly. Existing injection-molded gears suffer from unstable connections between the gear and the spindle, posing a risk of gear movement along the spindle. Furthermore, the use of different materials for the gear and spindle leads to differences in deformation when the ambient temperature changes, resulting in poor overall stability. Utility Model Content

[0004] (I) Purpose of the utility model

[0005] The purpose of this invention is to provide an injection-molded gear device that solves the problems of unstable gear position and the impact of temperature changes on the overall structural stability in traditional injection-molded gear devices.

[0006] (II) Technical Solution

[0007] To solve the above problems, this utility model provides an injection molding gear device, including a gear assembly and a main shaft, wherein the gear assembly is sleeved on the main shaft and connected to the main shaft;

[0008] The gear assembly includes a gear structure and an injection molding limiting part. The gear structure is fixedly connected to the injection molding limiting part. A deformation groove group and an overflow groove are formed on the main shaft. The gear structure is sleeved on the outside of the deformation groove group. The injection molding limiting part is located on the outside of the overflow groove. A boss is provided on the inner side of the injection molding limiting part. The boss is adapted to the overflow groove and is located inside the overflow groove.

[0009] Preferably, the gear assembly includes one of the injection-molded limiting parts, which is a tubular structure and sleeved on the outside of the overflow groove, and the boss is a circular structure and is injection-molded along the circumference of the overflow groove; or,

[0010] The injection molding limiting part has an arc-shaped structure and is located outside the overflow groove. The boss has an arc-shaped structure and is injection molded into the overflow groove.

[0011] Preferably, the gear assembly includes a plurality of injection molding limiting parts, all of which are arc-shaped structures. The plurality of injection molding limiting parts are evenly distributed on the outer side of the overflow groove, and the bosses on the plurality of injection molding limiting parts are arc-shaped structures and are injection molded into the overflow groove.

[0012] Preferably, the deformation groove group includes multiple longitudinal grooves, which are arranged parallel to the axis of the main shaft and uniformly distributed along the same circumference of the main shaft.

[0013] Preferably, the longitudinal groove is a V-shaped groove.

[0014] Preferably, the tops of two adjacent longitudinal grooves are flush with the periphery of the main shaft.

[0015] Preferably, the injection-molded gear device further includes a Hall effect detection component, which is connected to the gear assembly and is used to detect the operating status of the gear assembly.

[0016] Preferably, the Hall detection assembly includes a magnet and a Hall sensor. The magnet is connected to the gear structure, the Hall sensor is located above the magnet, the magnet and the gear structure rotate together, and the Hall sensor senses the change in the magnetic field during the rotation of the magnet.

[0017] Preferably, the gear structure has a mounting groove, and the magnet is disposed in the mounting groove.

[0018] Preferably, the gear structure has a groove formed thereon, the mounting groove and the groove are arranged circumferentially along the gear structure, and the groove is located outside the mounting groove.

[0019] (III) Beneficial Effects

[0020] The above-mentioned technical solution of this utility model has the following beneficial technical effects:

[0021] 1. The overflow groove on the spindle and the boss of the injection-molded limiting part on the gear assembly form an inlay structure, which can withstand greater composite loads compared to traditional single interference fits or key connections. For example, in transmission scenarios with frequent forward and reverse rotation, it can effectively avoid relative slippage between the gear and the spindle, especially the slippage of the gear structure on the spindle, reducing the risk of transmission failure due to loose connection.

[0022] 2. The overflow groove design provides a flow channel for the injection molding material, making it easier for the molten material to fill the gap between the gear and the spindle, reducing molding defects such as bubbles and short runs, and lowering the scrap rate. At the same time, one-piece injection molding eliminates later assembly processes such as press fitting and welding, significantly improving production efficiency, and is especially suitable for large-scale mass production.

[0023] 3. A deformation groove group is set on the main shaft, and the gear structure is fitted on the outside of the deformation groove group. The deformation groove group makes the gear structure evenly distributed on the outside, avoiding stress concentration. In addition, when the gear assembly and the main shaft are made of different materials, such as when the main shaft is made of metal, the thermal deformation of the injection molded gear assembly is much greater than that of the main shaft when the temperature changes. The deformation groove group provides thermal deformation space for the gear assembly, effectively preventing the deformation of the gear assembly and extending the service life of the overall structure. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of an injection molding tooth device provided by this utility model;

[0025] Figure 2 This is a schematic diagram of the main shaft structure according to the first embodiment of the present invention;

[0026] Figure 3 This is a cross-sectional view of the main shaft deformation groove assembly according to the first embodiment of this utility model;

[0027] Figure 4 This is a schematic diagram of the Hall detection component and gear structure according to the second embodiment of the present invention;

[0028] Figure 5 This is a schematic diagram showing the position of the Hall detection component and gear structure according to the second embodiment of this utility model;

[0029] Figure 6 This is a schematic diagram of the gear structure according to the second embodiment of the present utility model;

[0030] Figure 7 This is a cross-sectional view of the gear structure according to the second embodiment of this utility model.

[0031] Figure label:

[0032] 1. Gear assembly; 11. Gear structure; 11a. Mounting groove; 11b. Groove; 12. Injection molding limiting part;

[0033] 2. Main shaft; 2a. Deformation groove group; 201a. Longitudinal groove; 2b. Overflow groove;

[0034] 3. Hall effect detection component; 31. Magnet; 32. Hall effect sensor. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that these descriptions are merely exemplary and not intended to limit the scope of this utility model. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of this utility model.

[0036] The accompanying drawings show schematic diagrams of layer structures according to embodiments of the present invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0037] Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0038] Combination Figures 1 to 3 This utility model provides an injection molding gear device, including a gear assembly 1 and a main shaft 2. The gear assembly 1 is sleeved on the main shaft 2 and connected to the main shaft 2. The gear assembly 1 includes a gear structure 11 and an injection molding limiting part 12. The gear structure 11 is fixedly connected to the injection molding limiting part 12. A deformation groove group 2a and an overflow groove 2b are formed on the main shaft 2. The gear structure 11 is sleeved on the outside of the deformation groove group 2a. The injection molding limiting part 12 is located on the outside of the overflow groove 2b. A boss is provided on the inner side of the injection molding limiting part 12. The boss is adapted to the overflow groove 2b and is located inside the overflow groove 2b.

[0039] Specifically, the gear assembly 1 consists of a gear structure 11 and an injection-molded limiting part 12, which undertakes the transmission function and is connected to the main shaft 2 through the injection-molded limiting part 12. The main shaft 2 provides support, and its deformation groove group 2a and overflow groove 2b provide a mechanical interlocking structure for the injection connection. The deformation groove group 2a provides internal deformation space for the gear structure 11. The overflow groove 2b is filled with the boss of the injection-molded limiting part 12 to enhance axial fixation.

[0040] It should be noted that during injection molding, the boss of the injection limiting part 12 flows into the overflow groove 2b to form an axial fit. The specific connection relationship between the gear structure 11 and the injection limiting part 12 is not limited here. It can be a separate design with a fixed connection, or it can be an integrated design, that is, the gear structure 11 and the injection limiting part 12 are injection molded at the same time. The specific positional relationship between the gear structure 11 and the deformation groove group 2a outside the deformation groove group 2a is not restricted. When the injection molding limiting part 12 can meet the connection strength between the gear assembly 1 and the main shaft 2, the gear structure 11 does not need to extend into the deformation groove group 2a during injection molding. At this time, the specific location of the gap between the gear structure 11 and the deformation groove group 2a is not restricted. Adaptive design can be made according to the actual situation during injection molding. For example, before injection molding, the same filling structure can be fitted into the outside of the deformation groove group 2a. After injection molding, the filling structure can be removed. Alternatively, when the gear assembly 1 is integrally injection molded, the gear structure 11 can be embedded in the deformation groove group 2a. The material of the gear structure 11 flows into the deformation groove group 2a to form a radial fit. At this time, the boss of the injection molding limiting part 12 forms a double limit, so that the gear assembly 1 and the main shaft 2 are firmly connected and cooperate to transmit torque and axial force.

[0041] With this design, the overflow groove 2b on the spindle 2 and the boss of the injection molding limiting part 12 on the gear assembly 1 form an interlocking structure, which can withstand greater composite loads compared to traditional single interference fits or key connections. For example, in transmission scenarios with frequent forward and reverse rotation, it can effectively prevent relative slippage between the gear and the spindle 2, especially the slippage of the gear structure 11 on the spindle 2, reducing the risk of transmission failure due to loose connections. The design of the overflow groove 2b provides a flow channel for the injection molding material, making it easier for the molten material to fill the gap between the gear and the spindle 2, reducing molding defects such as bubbles and material shortages, and lowering the scrap rate. At the same time, the one-piece injection molding eliminates the need for later assembly processes such as press fitting and welding, significantly improving production efficiency, and is especially suitable for large-scale mass production. A deformation groove group 2a is provided on the main shaft 2, and the gear structure 11 is sleeved on the outside of the deformation groove group 2a. The deformation groove group 2a makes the gear structure 11 evenly distributed on the outside, avoiding stress concentration. In addition, when the gear assembly 1 and the main shaft 2 are made of different materials, such as when the main shaft 2 is made of metal, the amount of thermal deformation of the injection-molded gear assembly 1 is much greater than the amount of deformation of the main shaft 2 when the temperature changes. The deformation groove group 2a provides thermal deformation space for the gear assembly 1, effectively preventing the deformation of the gear assembly 1 and extending the service life of the overall structure.

[0042] It should be noted that the specific number of injection-molded limiting parts 12 and the specific form in which the bosses of the injection-molded limiting parts 12 are embedded in the overflow groove 2b are not limited here. In one optional case, the gear assembly 1 includes an injection-molded limiting part 12. In this case, the specific structure of the injection-molded limiting part 12 is not limited. It can be a tubular structure and sleeved on the outside of the overflow groove 2b. The boss is a circular structure and is injection-molded and filled along the periphery of the overflow groove 2b. In this case, the injection-molded limiting part 12 completely surrounds the overflow groove 2b, and the boss is embedded in the overflow groove 2b in a complete ring shape, achieving full circumferential limiting and uniform force distribution. Alternatively, the injection-molded limiting part 12 is an arc-shaped structure. The injection-molded limiting part 12 is located on the outside of the overflow groove 2b, and the boss is an arc-shaped structure and is injection-molded and filled in the overflow groove 2b. In this case, the injection-molded limiting part 12 partially surrounds the overflow groove 2b, and the boss is embedded in the overflow groove 2b at the surrounded position.

[0043] With this design, the injection molding limiting part 12 adopts a tubular full-circumference wrapping design, which is suitable for scenarios that require uniform axial limiting, such as in the cylindrical gear structure 11. It can balance the axial forces in all directions and prevent gear wobble. The injection molding limiting part 12 adopts an arc-shaped local reinforcement design, which can specifically strengthen the stress area in irregular structures such as sector gears, while reducing the amount of material used in non-stress areas, thus achieving lightweight design.

[0044] In another alternative embodiment, the gear assembly 1 includes multiple injection-molded limiting portions 12, each of which is an arc-shaped structure. These multiple injection-molded limiting portions 12 are evenly distributed on the outer side of the overflow groove 2b. The bosses on the multiple injection-molded limiting portions 12 are arc-shaped and are injection-molded into the overflow groove 2b. Specifically, the multiple arc-shaped injection-molded limiting portions 12 are evenly distributed on the outer side of the overflow groove 2b, and the bosses of each injection-molded limiting portion 12 partially fill the overflow groove 2b. The multiple sets of arc-shaped structures disperse axial forces, avoiding stress concentration in a single injection-molded limiting portion 12. The evenly distributed design makes force transmission more uniform, adapting to the force characteristics of asymmetrical gears, such as sector gears with eccentric loads.

[0045] With this configuration, multiple arc-shaped injection molding limiting parts 12 are evenly distributed circumferentially, distributing the axial force to multiple contact points. The load on a single injection molding limiting part 12 is reduced, and even if one injection molding limiting part 12 is damaged due to fatigue, the remaining structures can still temporarily bear the load, improving the system's fault tolerance. Furthermore, the number of injection molding limiting parts 12 can be adaptively adjusted according to the specific application scenario of the gear assembly 1. With similar structures, the main shaft 2 structure can be universally applicable, reducing modification costs.

[0046] It should be noted that the specific structural form of the deformation groove group 2a and its layout on the main shaft 2 are not limited here. Figure 2Taking the position of the main shaft 2 as an example, the main shaft 2 is vertically positioned in the figure. In a preferred embodiment, the deformation groove groups 2a are distributed circumferentially at the same horizontal cross-sectional position of the main shaft 2, that is, perpendicular to the axial direction of the main shaft 2. At this time, the deformation groove groups 2a can be parallel to the axial direction of the main shaft 2; or they can surround the circumference of the main shaft 2. In this case, each deformation groove in the deformation groove group 2a is parallel to each other and is formed in a spiral manner on the circumference of the main shaft 2. It should be noted that the lengths of the multiple deformation grooves are the same, that is, the highest and lowest points of all deformation grooves are at the same horizontal cross-sectional position of the main shaft 2.

[0047] In a preferred embodiment, the deformation groove group 2a includes a plurality of longitudinal grooves 201a, which are arranged parallel to the axis of the main shaft 2 and uniformly distributed along the same circumference of the main shaft 2. Specifically, as shown... Figure 2 As shown, multiple longitudinal grooves 201a are parallel to the axis of the main shaft 2 and are evenly distributed on the same horizontal interface of the main shaft 2. This arrangement ensures that the multiple longitudinal grooves 201a are evenly distributed circumferentially, making the meshing force between the gear structure 11 and the main shaft 2 symmetrical in the circumferential direction. This avoids localized wear due to uneven force distribution and ensures stable torque transmission efficiency. Under sudden loads, such as the impact torque at startup, the evenly distributed groove structure can quickly disperse stress, preventing localized groove overload fracture and improving the overall service life of the structure.

[0048] It should be noted that the specific structural form of the longitudinal groove 201a is not limited here, as long as it can provide space for thermal deformation of the gear structure 11 and meet the connection strength requirements between the gear structure 11 and the main shaft 2. In a preferred embodiment, the longitudinal groove 201a is a V-groove.

[0049] With this design, the two inclined surfaces of the V-groove form an abutment with the inner side of the gear structure 11. When the gear structure 11 is under force, the normal pressure between the injection molding material and the groove wall of the V-groove increases with the increase of the load, and the friction force increases accordingly, enhancing the anti-loosening ability. This is especially suitable for high-frequency vibration scenarios, such as engineering machinery gearboxes. The gradient cross-section design of the V-groove has lower requirements for the fluidity of the injection molding material. Compared with the right-angle corner of the rectangular groove, it can fully fill the groove or provide suitable deformation space when the gear structure 11 deforms, ensuring the connection strength between the gear structure 11 and the longitudinal groove 201a.

[0050] In a preferred embodiment, the tops of two adjacent longitudinal grooves 201a are flush with the periphery of the main shaft 2. Specifically, as shown... Figure 2 and Figure 3 As shown, the longitudinal grooves 201a are arranged parallel to the axis of the main shaft 2 and are evenly distributed in the same cross section of the main shaft 2. At this time, the highest point of the deformable groove group 2a is formed between two adjacent longitudinal grooves 201a. The highest point is flush with the periphery of the main shaft 2, that is, the outer wall, to ensure the support effect of the deformable groove group 2a on the gear structure 11.

[0051] With this configuration, the top of the longitudinal groove 201a is flush with the periphery of the main shaft 2, ensuring complete contact between the inner circumference of the gear structure 11 and the outer circumference of the main shaft 2. This prevents uneven stress from causing the gear structure 11 to wobble on the main shaft 2. When the longitudinal groove 201a is injection molded into the inner side of the gear structure 11, the highest point of the longitudinal groove 201a is flush with the periphery of the main shaft 2. This also ensures that the gear structure 11 has a consistent structure on the outer side of the deformation groove group 2a, avoiding stress concentration caused by structural differences and improving the connection stability and service life between the gear structure 11 and the deformation groove group 2a.

[0052] Combination Figures 4 to 7 In a preferred embodiment, the injection molding gear device further includes a Hall effect detection component 3, which is connected to the gear assembly 1 and is used to detect the operating status of the gear assembly 1.

[0053] Specifically, the Hall effect sensor 3 is directly connected to the gear assembly 1 to accurately acquire the operating status data of the gear assembly 1, such as the rotation speed, rotation angle, or vibration information during the rotation process, and to determine whether the rotation posture is flat.

[0054] With this setup, the Hall effect sensor 3 provides real-time feedback on the operating status of the gear assembly 1, facilitating precise speed control and overload protection, and enhancing the equipment's intelligence level. Compared to photoelectric sensors, Hall effect sensors are unaffected by light and can operate stably in harsh environments such as dust and humidity, ensuring the continuous and stable operation of the gear assembly 1.

[0055] It should be noted that the specific structure of the Hall effect detection component 3 is not limited here. In a preferred embodiment, the Hall effect detection component 3 includes a magnet 31 and a Hall sensor 32. The magnet 31 is connected to the gear structure 11, and the Hall sensor 32 is located above the magnet 31. The magnet 31 and the gear structure 11 rotate together, and the Hall sensor 32 senses the changes in the magnetic field during the rotation of the magnet 31. Specifically, the magnet 31 is disposed on the gear structure 11, and the Hall sensor 32 is located above the magnet 31. At this time, the magnet 31 rotates together with the gear structure 11, and the position of the Hall sensor 32 is relatively fixed, such as being disposed on other structures near the gear structure 11 that rotate relative to the gear structure 11. This can be adapted according to the specific application scenario of the injection molding gear device. The magnet 31 is arranged circumferentially on the gear structure 11, forming a magnetic field that rotates together with the gear structure 11. The Hall sensor 32 is located above the magnet 31. By detecting the changes in the magnetic field, the movement of the magnet 31 is determined, thereby obtaining the rotation status of the gear structure 11. For example, by detecting the frequency and waveform changes of the magnetic field, it can be determined whether the gear assembly 1 has problems such as jamming, shaking or slipping. Especially under the structure of the combined deformation groove group 2a, the connection strength between the gear structure 11 and the main shaft 2 may change with temperature changes. By detecting the movement of the gear structure 11, it can be ensured that the gear structure 11 always maintains a stable rotation state under different temperature conditions.

[0056] It should be noted that the specific connection method between the magnet 31 and the gear structure 11 is not limited here, as long as the magnet 31 and the gear structure 11 can rotate synchronously and stably. In a preferred embodiment, the gear structure 11 has a mounting groove 11a, and the magnet 31 is disposed in the mounting groove 11a. Specifically, the mounting groove 11a fixes the magnet 31, ensuring that the magnet 31 and the gear structure 11 rotate synchronously, avoiding displacement that could lead to detection deviations. It can be integrally molded during injection molding, and the gear structure 11 can enclose the magnet 31, or the mounting groove 11a can be pre-reserved during molding for later assembly of the magnet 31.

[0057] With this design, the mounting groove 11a encloses and limits the magnet 31, avoiding the risk of the magnet 31 falling off due to vibration, which is common in traditional adhesive fixing methods. Especially in environments with temperature changes, it can resist the magnet 31 falling off due to adhesive failure or thermal deformation of the gear structure 11. If the mounting groove 11a and the gear structure 11 are injection molded as a single unit, the magnet 31 and the gear structure 11 can be integrated, reducing interference with surrounding components and simplifying the assembly process. Furthermore, during the operation of the injection-molded gear, the gear structure 11 deforms more than traditional metal gears due to stress. The mounting groove 11a effectively prevents this deformation, thus preventing the magnet 31 on the gear structure 11 from cracking and being damaged.

[0058] The specific structural relationship between the mounting groove 11a and the magnet 31 is not limited here. The magnet can fit into the mounting groove 11a, or the size of the mounting groove 11a can be set to be larger than the size of the magnet 31. In a preferred embodiment, the volume of the mounting groove 11a is larger than the volume of the magnet 31. Specifically, the magnet 31 is completely disposed within the mounting groove 11a. After the magnet 31 is fixed in the mounting groove 11a, a gap is left between the magnet 31 and the side wall of the mounting groove 11a. At this time, a fixing structure for the magnet 31 can be provided in the mounting groove 11a, such as forming a protruding limiting structure on the side wall of the groove to engage the magnet 31 within the mounting groove 11a.

[0059] With this configuration, the thermal expansion coefficients of the injection-molded gear structure 11 and the magnet 31 differ significantly. The reserved gap can prevent structural deformation caused by the expansion difference when the temperature changes. The gap provides deformation space for the gear structure 11, which on the one hand prevents the magnet 31 from being excessively squeezed and damaging the structure, ensuring the installation stability of the magnet 31. At the same time, it prevents the deformation of the gear structure 11 from causing the position of the magnet 31 to change when the temperature changes, thereby ensuring that the data detected by the Hall sensor 32 is relatively stable. On the other hand, it prevents the gear structure 11 from being damaged due to lack of deformation space, ensuring that the gear structure 11 can maintain stable operation.

[0060] Combination Figure 6 and Figure 7 In a preferred embodiment, a groove 11b is formed on the gear structure 11. The mounting groove 11a and the groove 11b are arranged circumferentially around the gear structure 11, with the groove 11b located outside the mounting groove 11a. Specifically, the mounting groove 11a is formed circumferentially around the main shaft 2 on the gear structure 11, and the groove 11b is formed on the outer periphery of the mounting groove 11a. With this arrangement, the groove 11b is positioned between the outer periphery of the magnet 31 mounted on the gear structure 11 and the gear ring. When the gear structure 11 is subjected to force, the force is transmitted along the bottom of the groove 11b, preventing uneven force distribution that could cause the magnet 31 to easily break, further ensuring the stability of the magnet 31 and the accuracy of the monitoring data.

[0061] It should be understood that the specific embodiments described above are merely illustrative or explanatory of the principles of this utility model and do not constitute a limitation thereof. Therefore, any modifications, equivalent substitutions, improvements, etc., made without departing from the spirit and scope of this utility model should be included within its protection scope. Furthermore, the appended claims are intended to cover all variations and modifications falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

Claims

1. An injection-molded gear device, characterized in that, The injection molding gear device includes a gear assembly (1) and a main shaft (2), wherein the gear assembly (1) is sleeved on the main shaft (2) and connected to the main shaft (2); The gear assembly (1) includes a gear structure (11) and an injection molding limiting part (12). The gear structure (11) is fixedly connected to the injection molding limiting part (12). A deformation groove group (2a) and an overflow groove (2b) are formed on the main shaft (2). The gear structure (11) is sleeved on the outside of the deformation groove group (2a). The injection molding limiting part (12) is disposed on the outside of the overflow groove (2b). A boss is provided on the inner side of the injection molding limiting part (12). The boss is adapted to the overflow groove (2b) and is disposed in the overflow groove (2b).

2. The injection-molded gear device according to claim 1, characterized in that, The gear assembly (1) includes an injection molding limiting part (12), which is a tubular structure and sleeved on the outside of the overflow groove (2b). The boss is an annular structure and is injection molded along the circumference of the overflow groove (2b); or, The injection molding limiting part (12) has an arc-shaped structure and is located on the outside of the overflow groove (2b). The boss has an arc-shaped structure and is injection molded into the overflow groove (2b).

3. The injection-molded gear device according to claim 1, characterized in that, The gear assembly (1) includes a plurality of injection molding limiting parts (12), each of which is an arc-shaped structure. The plurality of injection molding limiting parts (12) are evenly distributed on the outside of the overflow groove (2b), and the bosses on the plurality of injection molding limiting parts (12) are arc-shaped structures and are injection molded into the overflow groove (2b).

4. The injection-molded gear device according to claim 1, characterized in that, The deformation groove group (2a) includes multiple longitudinal grooves (201a), which are arranged parallel to the axis of the main shaft (2) and uniformly distributed along the same circumference of the main shaft (2).

5. The injection-molded gear device according to claim 4, characterized in that, The longitudinal groove (201a) is a V-shaped groove.

6. The injection-molded gear device according to claim 5, characterized in that, The tops of two adjacent longitudinal grooves (201a) are flush with the periphery of the main shaft (2).

7. The injection-molded gear device according to claim 1, characterized in that, The injection molding gear device also includes a Hall effect detection component (3), which is connected to the gear assembly (1) and is used to detect the operating status of the gear assembly (1).

8. The injection-molded gear device according to claim 7, characterized in that, The Hall detection component (3) includes a magnet (31) and a Hall sensor (32). The magnet (31) is connected to the gear structure (11). The Hall sensor (32) is located above the magnet (31). The magnet (31) and the gear structure (11) rotate together. The Hall sensor (32) senses the change in the magnetic field during the rotation of the magnet (31).

9. The injection-molded gear device according to claim 8, characterized in that, The gear structure (11) has a mounting groove (11a) formed therein, and the magnet (31) is disposed in the mounting groove (11a).

10. The injection-molded gear device according to claim 9, characterized in that, A groove (11b) is formed on the gear structure (11), the mounting groove (11a) and the groove (11b) are arranged circumferentially along the gear structure (11), and the groove (11b) is located outside the mounting groove (11a).

Images