A motor grounding structure

Abstract

The utility model provides a kind of motor grounding structure, including motor casing, circuit board, end cover and elastic sheet;Elastic sheet is installed on circuit board, and circuit board is fixed in motor casing by end cover, and make elastic sheet abut on motor casing;Elastic sheet includes integrally formed U-shaped fixed section, elastic bending section and limit thrust section;The lower side of U-shaped fixed section is fixed on circuit board;Elastic bending section is bent upwards and connected in the upper end of U-shaped fixed section, the upper end of limit thrust section is connected with elastic bending section upper end, the lower end of limit thrust section extends to U-shaped fixed section, when elastic sheet is pressed tightly, elastic bending section abuts on motor casing, and the lower end of limit thrust section abuts on U-shaped fixed section.The utility model is limited to fixed circuit board by end cover, ensure that the relative position of circuit board and motor casing is stable, provide basic guarantee for elastic sheet grounding;Elastic sheet integrally formed U-shaped fixed section, elastic bending section and limit thrust section form complete grounding conducting structure.

Description

Technical Field

[0001] This utility model relates to the field of motor grounding technology, and more specifically, to a motor grounding structure. Background Technology

[0002] As core driving components in automobiles, consumer electronics, and smart homes, the reliable grounding of the metal casing and internal circuitry of micro motors is crucial for ensuring electrical safety. According to the standard "Rotating Electrical Machines Ratings and Performance" (GB-755-2008), non-energized conductive parts of the motor must be forcibly grounded to conduct leakage current in case of faults such as winding insulation damage, preventing electric shock and motor burnout, while also suppressing electromagnetic radiation to ensure EMC testing. Currently, the mainstream grounding methods for micro motors are limited by their compact structural space and have significant drawbacks, mainly falling into the following three categories: 1. Screw-lead combination grounding: One end of the wire is fixed to the motor housing using a grounding screw, and the other end is soldered to the circuit board ground terminal or equipment grounding frame. This requires machining threaded holes in a narrow housing, demanding high machining precision, and the assembly process is cumbersome and difficult to adapt to automated production. Furthermore, vibration can easily cause loose connections and increased grounding resistance. 2. Grounding via welded terminals: Customized metal terminals are welded to the motor housing using a spot welding machine, and then connected to the grounding circuit via plug-in or welding methods. Customized terminals and special molds are required for different motors, with a mold production cycle of 4-6 weeks. This method is only suitable for mass production, and high-temperature welding can easily damage the winding insulation. 3. Radial bump contact grounding: A protruding conductor is installed on the inner diameter of the motor housing or on the terminal block, and grounding is achieved through radial compression contact. This structure is prone to interference with components such as end caps during assembly, leading to motor concentricity deviation, which directly affects operational stability and output accuracy.

[0003] Therefore, there is an urgent need for a grounding solution that combines low contact resistance, vibration resistance, and adaptability to flexible manufacturing, in order to solve the problems of difficult processing, low assembly efficiency, insufficient reliability, and high cost of existing solutions. Utility Model Content

[0004] This utility model aims to solve the technical problems of existing mainstream solutions, such as difficult processing, poor compatibility, and low reliability. In order to overcome the above-mentioned defects of the prior art, this utility model provides a method that connects the grounding contact of the motor housing through a spring on the PCB board, which can effectively reduce the grounding impedance, ensure stable transmission of high-frequency signals, and solve the contact failure problem of traditional fixed grounding methods under vibration and temperature deformation scenarios. The spring can automatically compensate for assembly tolerances and dynamic displacement through its own elasticity, and always maintain reliable grounding contact.

[0005] To achieve the purpose of this utility model, the following technical solution is adopted: A motor grounding structure includes a motor housing, a circuit board, an end cap, and a spring clip. The spring clip is mounted on the circuit board, which is fixed inside the motor housing by the end cap, causing the spring clip to abut against the motor housing. The spring clip includes an integrally formed U-shaped fixing section, an elastic bending section, and a limiting thrust section. The lower side of the U-shaped fixing section is fixed to the upper surface of the circuit board. The elastic bending section is bent upward and connected to the upper end of the U-shaped fixing section. The upper end of the limiting thrust section is connected to the upper end of the elastic bending section, and the limiting thrust section is bent downward, extending its lower end to the U-shaped fixing section. When the spring clip is in a pressed contact state, the elastic bending section abuts against the motor housing, and the lower end of the limiting thrust section abuts against the U-shaped fixing section. This structure uses an end cap to limit and fix the circuit board, ensuring the relative position of the circuit board and the motor housing is stable, providing a basic guarantee for the spring contact grounding. The integrally formed U-shaped fixing section, elastic bending section, and limiting thrust section of the spring contact form a complete grounding conduction structure. The U-shaped fixing section ensures a firm connection between the spring contact and the circuit board, while the elastic bending section reliably abuts against the motor housing after the end cap is installed, achieving stable current conduction and avoiding grounding failure caused by loose connections in traditional grounding methods. The elastic bending section has elastic deformation capability, which can automatically compensate for assembly tolerances and dynamic displacements caused by vibration and temperature differences during motor operation, always maintaining effective contact with the motor housing, solving the contact failure problem of traditional fixed grounding under vibration and temperature difference deformation scenarios.

[0006] Preferably, the circuit board is provided with positioning holes; the lower end of the U-shaped fixing section is bent downward to form an L-shaped insertion section, and the right angle of the L-shaped insertion section is a rounded transition. The L-shaped insertion section is inserted into the positioning holes. The positioning holes on the circuit board cooperate with the L-shaped insertion section of the spring piece, providing a clear positioning reference for the installation of the spring piece, avoiding the spring piece from shifting during assembly, ensuring that the elastic bending section of the spring piece can be accurately aligned with the motor housing, ensuring the stability of the grounding conduction path, and solving the problem of motor concentricity deviation caused by assembly interference in traditional radial bump contact grounding.

[0007] Preferably, the outer wall of the lower side of the U-shaped fixing section is horizontally attached to the surface of the circuit board, and the attachment point between the lower side and the circuit board is fixed by welding. This structure maximizes the contact area between the spring and the circuit board, reduces the contact resistance between them, improves the grounding current conduction efficiency, ensures stable transmission of high-frequency signals, and meets the low impedance requirements of motor grounding.

[0008] Preferably, the angle between the upper side of the elastic bending section and the U-shaped fixed section is 135°-165°. This angle design ensures that the elastic bending section forms a reasonable elastic deformation angle after the end cap is installed. This guarantees that the elastic bending section has sufficient elastic force to maintain reliable contact with the motor housing, while avoiding excessive deformation resistance due to an excessively small angle or insufficient elastic force due to an excessively large angle. This perfectly matches the "high-pressure clamping elastic range" requirement of the spring sheet.

[0009] Preferably, the limiting thrust section is V-shaped, with its upper end connected to the highest end of the elastic bending section. The limiting thrust section and the elastic bending section bend together to form a downward-opening U-shaped contact area. The lower end of the limiting thrust section is located between the lower and upper sides. When the spring is pressed, the U-shaped contact area is in close contact with the motor housing. The V-shaped point of the limiting thrust section is in close contact with the inner wall of the lower side of the U-shaped fixing section, and the lower end of the limiting thrust section is in close contact with the inner wall of the upper side of the U-shaped fixing section. When the spring is pressed, the U-shaped contact area is in close contact with the motor housing, increasing the contact area between the spring and the motor housing, further reducing grounding impedance, improving current conduction efficiency, and ensuring stable transmission of high-frequency signals. Simultaneously, the U-shaped contact area can disperse contact pressure, preventing excessive local pressure from damaging the motor housing or the spring surface, and protecting the integrity of the grounding contact surface.

[0010] Preferably, the lower left and right sides of the U-shaped fixing section are integrally formed and bent upwards to form limiting plates; the limiting thrust section is limited between the two limiting plates. Confining the limiting thrust section between the two limiting plates prevents lateral displacement of the limiting thrust section during the deformation of the spring sheet, ensuring that the limiting thrust section can accurately abut against the U-shaped fixing section and guaranteeing stable operation of the limiting function; at the same time, the limiting plates make the layout of the spring sheet components more regular, reducing internal structural interference caused by component displacement.

[0011] Preferably, the lower end face of the motor housing has a downward-facing mounting opening; a positioning protrusion is provided on the circuit board at the mounting opening, and the positioning protrusion is inserted into the mounting opening; the spring is mounted on the positioning protrusion and located in the mounting opening, and when the spring is in a compressed state, the elastic bending section is in close contact with the inner wall of the mounting opening. The mounting opening of the motor housing and the positioning protrusion of the circuit board cooperate to precisely limit the spring within the mounting opening, making full use of the unused space at the end of the motor housing and adapting to the compact structure requirements of micro motors; the positioning protrusion provides a dedicated mounting area for the spring, avoiding the spring from competing for space with other components on the circuit board, reducing assembly interference, and improving the utilization rate of the internal space of the motor.

[0012] The advantages of this invention are: the elastic bending section of the spring sheet has an automatic compensation function, which can adapt to the assembly tolerances and dynamic displacements caused by vibration and temperature differences during motor operation, and always maintain effective contact with the motor housing, solving the contact failure problem of traditional fixed grounding; the large-area contact between the U-shaped contact area and the motor housing, and the horizontal bonding welding between the U-shaped fixed section and the circuit board, both significantly reduce the grounding impedance, ensure stable transmission of high-frequency signals, and meet EMC testing requirements; the double protection of the limit thrust section and the limit plate prevents excessive deformation or offset of the spring sheet, ensuring long-term stable operation of the grounding structure. There is no need to machine high-precision threaded holes in the motor housing, nor is it necessary to customize special terminals and molds; assembly can be completed simply by the cooperation of the spring sheet with the circuit board and end cap, simplifying the process and adapting to automated production. Attached Figure Description

[0013] Figure 1 is a schematic diagram of the motor grounding structure of this utility model. Figure 2 is a partially enlarged view of the motor grounding structure of this utility model. Figure 3 is an exploded view of the motor grounding structure of this utility model. Figure 4 is a schematic diagram of the spring contact of this utility model. Figure 5 is a cross-sectional view of the spring contact of this utility model.

[0014] Explanation of reference numerals in the attached figures: 1. Motor housing; 11. Mounting port; 2. Circuit board; 21. Positioning insertion hole; 22. Positioning protrusion; 3. End cover; 4. Spring piece; 41. U-shaped fixing section; 411. Lower side; 412. Upper side; 42. Elastic bending section; 43. Limiting thrust section; 431. V-shaped point; 432. End point; 44. L-shaped insertion section; 441. Right angle; 45. U-shaped contact area; 46. Limiting plate. Detailed Implementation

[0015] First, those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the embodiments of this application and are not intended to limit the scope of protection of the embodiments of this application. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.

[0016] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0017] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0018] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0019] The vertical positions mentioned in the embodiments are only for structural description based on the orientation in the accompanying drawings. In specific applications, the orientation should be determined according to the specific installation location.

[0020] like Figures 1 to 5As shown, a motor grounding structure includes a motor housing 1, a circuit board 2, an end cap 3, and a spring 4. The spring 4 is mounted on the circuit board 2, and the circuit board 2 is fixed inside the motor housing 1 by the end cap 3, so that the spring 4 abuts against the motor housing 1. The spring 4 includes an integrally formed U-shaped fixing section 41, an elastic bending section 42, and a limiting thrust section 43. The lower side 411 of the U-shaped fixing section 41 is fixed to the upper end face of the circuit board 2. The elastic bending section 42 is bent upward and connected to the upper end of the U-shaped fixing section 41 (the end of the upper side 412). The upper end of the limiting thrust section 43 is connected to the upper end of the elastic bending section 42, and the limiting thrust section 43 is bent downward and the lower end of the limiting thrust section 43 extends to the U-shaped fixing section 41. When the end cap 3 is installed (the spring 4 is in a pressed contact state), the elastic bending section 42 abuts against the motor housing 1, and the lower end of the limiting thrust section 43 abuts against the U-shaped fixing section 41. This structure uses the end cap 3 to limit and fix the circuit board 2, ensuring the relative position of the circuit board 2 and the motor housing 1 is stable, providing a basic guarantee for the grounding of the spring contact 4. The spring contact 4, with its integrally formed U-shaped fixing section 41, elastic bending section 42, and limiting thrust section 43, forms a complete grounding conduction structure. The U-shaped fixing section 41 ensures a stable connection between the spring contact and the circuit board 2, and the elastic bending section 42 reliably abuts against the motor housing 1 after the end cap 3 is installed, achieving stable current conduction and avoiding grounding failure caused by loose connections in traditional grounding methods. The elastic bending section 42 has elastic deformation capability, which can automatically compensate for assembly tolerances and dynamic displacements caused by vibration and temperature differences during motor operation, always maintaining effective contact with the motor housing 1, solving the contact failure problem of traditional fixed grounding such as screw-lead combination and welded terminals under vibration and temperature difference deformation scenarios. The limiting thrust section 43 abuts against the U-shaped fixing section 41, which can limit the excessive deformation of the elastic bending section 42. This ensures that the elastic bending section 42 is always in the effective elastic range to maintain sufficient contact force, and also prevents the spring sheet from being damaged due to excessive deformation, thus extending its service life.

[0021] like Figures 1 to 3As shown, a U-shaped mounting opening 11 with an opening facing downwards is provided on the lower end face of the motor housing 1; a positioning protrusion 22 is provided radially protruding from the mounting opening 11 on the circuit board 2, and the positioning protrusion 22 is inserted into the mounting opening 11; a spring piece 4 is mounted on the positioning protrusion 22 and located in the mounting opening 11. When the spring piece 4 is in a compressed state, the elastic bending section 42 is in close contact with the inner wall of the mounting opening 11. The mounting opening 11 of the motor housing 1 and the positioning protrusion 22 of the circuit board 2 cooperate to precisely limit the spring piece 4 within the mounting opening 11, making full use of the idle space at the end of the motor housing 1 and adapting to the compact structure requirements of the micro motor; the positioning protrusion 22 provides a dedicated mounting area for the spring piece 4, avoiding the spring piece 4 competing for space with other components on the circuit board 2 such as resistors and capacitors, reducing assembly interference, and improving the utilization rate of the internal space of the motor. The spring piece 4 is located inside the mounting opening 11 and the elastically bent section 42 is in close contact with the inner wall of the mounting opening 11. The inner wall of the mounting opening 11 is part of the motor housing 1 and has stable conductivity. The direct contact between the spring piece 4 and the inner wall of the mounting opening 11 shortens the grounding conduction path and reduces the grounding impedance. At the same time, the mounting opening 11 forms a surrounding protection for the spring piece 4, reducing the impact of external factors such as external vibration and foreign object collisions on the contact state between the spring piece 4 and the motor housing 1, and further ensuring the reliability of grounding.

[0022] like Figures 1 to 3 As shown, the circuit board 2 has vertically distributed positioning holes 21; the U-shaped fixing section 41 is U-shaped, and the lower end (the end of the lower side 411) of the U-shaped fixing section 41 is bent downward to form an L-shaped insertion section 44, and the right angle 441 of the L-shaped insertion section 44 is a rounded transition. The L-shaped insertion section 44 is vertically inserted into the positioning hole 21. The positioning hole 21 on the circuit board 2 cooperates with the L-shaped insertion section 44 of the spring piece 4 to provide a clear positioning reference for the installation of the spring piece 4, avoid the spring piece 4 from being offset during the assembly process, ensure that the elastic bending section 42 of the spring piece 4 can be accurately aligned with the motor housing 1, ensure the stability of the grounding conduction path, and solve the problem of motor concentricity deviation caused by assembly interference in traditional radial bump contact grounding. The right angle 441 of the L-shaped insertion section 44 adopts an arc-shaped transition. On the one hand, this reduces scratch damage to the edge of the positioning socket 21 during insertion, protecting the structural integrity of the circuit board 2 and the spring 4; on the other hand, it effectively contacts the housing when pressing different sizes, while avoiding tip discharge. The combined structure of the U-shaped fixing section 41 and the L-shaped insertion section 44 increases the contact area and connection points between the spring 4 and the circuit board 2. Compared with a single fixing method, this further improves the connection stability between the spring 4 and the circuit board 2, reduces the impact of vibration on the connection between the spring 4 and the circuit board 2, and indirectly ensures grounding reliability.

[0023] The production process of spring sheet 4 is as follows: stamping: continuous die stamping process is adopted, and the stamping accuracy is controlled within ±0.05mm. There are no burrs on the edge of spring sheet 4 (burr height ≤0.02mm) to avoid scratching the mating parts or generating metal chips. After forming, aging treatment (300℃×1h) is required to eliminate the internal stress of stamping and stabilize the elastic properties of spring sheet 4.

[0024] Surface treatment: Pretreatment requires three steps: degreasing, pickling, and activation to ensure the adhesion of the coating; the electroplating process adopts rack plating, and the current density is controlled at 1-2A / dm² to ensure the uniformity of the coating; after electroplating, a 24-hour neutral salt spray test (GB / T-10125) is performed, and the coating shows no corrosion or peeling.

[0025] Assembly process: The spring 4 and the circuit board 2 are connected by reflow soldering. The soldering temperature profile must match the characteristics of beryllium copper material, with a peak temperature ≤260℃ and a holding time of 30-60s. When assembling with the metal motor housing 1, the metal motor housing 1 is used for press-fitting to keep it in a high compression and high elasticity range.

[0026] like Figure 4 and Figure 5 As shown, the U-shaped fixing section 41 is horizontally positioned, and the outer wall of the lower side 411 of the U-shaped fixing section 41 is horizontally attached to the upper surface of the circuit board 2. The attachment point between the lower side 411 and the circuit board 2 is fixed by welding. By horizontally positioning the U-shaped fixing section 41 and horizontally attaching its outer wall to the surface of the circuit board 2, the contact area between the spring 4 and the circuit board 2 is maximized, the contact resistance between the spring 4 and the circuit board 2 is reduced, the grounding current conduction efficiency is improved, and the stable transmission of high-frequency signals is ensured, meeting the low impedance requirements of motor grounding. The attachment point is fixed by welding, forming a rigid connection, preventing relative loosening of the spring 4 and the circuit board 2 under vibration, further reducing the risk of increased grounding resistance. Compared with the loosening of the connection caused by vibration in screw-lead combination grounding, the grounding stability is significantly improved. The horizontal attachment and welding fixation method ensures that the connection state of each spring 4 and the circuit board 2 is uniform, reducing grounding performance fluctuations caused by assembly differences, improving the consistency of the grounding structure in mass production, and facilitating quality control.

[0027] like Figure 4 and Figure 5As shown, the elastic bending section 42 is bent upwards and connected to the upper end (end of the upper side 412) of the U-shaped fixed section 41, and the angle between the upper side 412 and the U-shaped fixed section 41 is 135°-165°. This angle design ensures that the elastic bending section 42 forms a reasonable elastic deformation angle after the end cover 3 is installed. This guarantees that the elastic bending section 42 has sufficient elastic force to maintain reliable contact with the motor housing 1, avoiding insufficient contact force leading to increased grounding resistance. Conversely, it avoids excessive deformation resistance due to an excessively small angle, preventing difficulties in installing the end cover 3, or insufficient elastic force due to an excessively large angle. This perfectly matches the "high-pressure clamping elastic range" requirement of the spring sheet 4. This angle range allows the elastic bending section 42 to unfold at a reasonable angle, meeting the grounding working stroke while avoiding interference with other internal motor components such as windings and capacitors. This ensures the compactness of the motor's internal structure, adapts to the limited structural space of micro-motors, and solves the assembly difficulties caused by space limitations in traditional grounding methods.

[0028] like Figure 4 and Figure 5 As shown, the limiting thrust section 43 is V-shaped. The upper end of the limiting thrust section 43 is connected to the highest end of the elastic bending section 42, and the limiting thrust section 43 and the elastic bending section 42 are bent to form a U-shaped contact area 45 with the opening facing downward. The lower end of the limiting thrust section 43 is located between the upper side 412 and the lower side 411 of the U-shaped fixing section 41. When the spring piece 4 is in the pressed state, the U-shaped contact area 45 is in close contact with the motor housing 1. The V-shaped point 431 of the limiting thrust section 43 (located between the upper side 412 and the lower side 411) is in close contact with the inner wall of the lower side 411 of the U-shaped fixing section 41. The lower end point 432 of the limiting thrust section 43 (on the side away from the U-shaped contact area 45) is in close contact with the inner wall of the upper side 412 of the U-shaped fixing section 41. When the spring 4 is pressed, the U-shaped contact area comes into close contact with the motor housing 1, increasing the contact area between the spring 4 and the motor housing 1, further reducing the grounding impedance, improving the current conduction efficiency, and ensuring stable transmission of high-frequency signals. At the same time, the U-shaped contact area 45 can disperse the contact pressure, preventing excessive local pressure from damaging the surface of the motor housing 1 or the spring 4, and protecting the integrity of the grounding contact surface.

[0029] like Figure 4 and Figure 5As shown, when the spring piece 4 is pressed, the V-shaped point 431 of the limiting thrust section 43 is in close contact with the inner wall of the lower side 411 of the U-shaped fixing section 41, and the endpoint 432 is in close contact with the inner wall of the upper side 412 of the U-shaped fixing section 41, forming a multi-point limiting, which precisely limits the deformation direction and deformation amplitude of the elastic bending section 42, ensuring that the elastic bending section 42 is always within the preset elastic range, maintaining sufficient contact force, and preventing the spring piece 4 from failing due to excessive deformation. At the same time, the multi-point contact further enhances the overall structural stability of the spring piece 4, reduces the impact of motor vibration on the deformation state of the spring piece 4, and ensures the continuity of grounding. By precisely limiting the elastic bending section 42 through the limiting thrust section 43, the elastic bending section 42 is prevented from contacting surrounding components such as capacitors and resistors due to excessive deformation, indirectly ensuring the safe distance between the spring piece 4 and other components, preventing short circuit risks, and improving the electrical safety of the motor.

[0030] like Figure 4 and Figure 5 As shown, the lower side 411 of the U-shaped fixing section 41 has integrally formed upper bending limit plates 46 on both sides, and the two limit plates 46 are symmetrically arranged. The limiting thrust section 43 is located between the two limit plates 46. The limiting thrust section 43 is confined between the two limit plates 46 to prevent the limiting thrust section 43 from shifting laterally during the deformation of the spring piece 4, ensuring that the limiting thrust section 43 can accurately abut against the U-shaped fixing section 41 and ensuring the stable operation of the limiting function; at the same time, the limit plates 46 make the layout of each component of the spring piece 4 more regular and reduce internal structural interference caused by component offset. The limiting plate 46 can guide the deformation direction of the elastic bending section 42 and the limiting thrust section 43, ensuring that their deformation is carried out along a preset path, and further improving the stability of the grounding of the spring piece 4. In addition, the limiting plate 46 can block external impurities such as dust and debris from entering the critical contact area inside the spring piece 4 to a certain extent, keeping the contact surfaces of the spring piece 4 with the U-shaped fixing section 41 and the motor housing 1 clean and avoiding increased contact resistance caused by impurities.

[0031] The final assembly and operation process is as follows: The circuit board 2 with the spring clip 4 is installed into the motor housing 1, ensuring the spring clip 4 is entirely within the mounting opening 11. Then, the end cover 3 is installed. During the locking process, the end cover 3 will compress the elastic bending section 42 of the spring clip 4, causing it to elastically deform. In the compressed state (e.g., Figure 4 As shown): The U-shaped contact area 45 of the spring 4 abuts tightly against the inner wall of the mounting opening 11 of the motor housing 1, forming a low-impedance grounding path. Simultaneously, the V-shaped point 431 of the limiting thrust section 43 abuts against the inner wall of one side of the U-shaped fixing section 41, while its endpoint 432 abuts against the inner wall of the other side of the U-shaped fixing section 41. This three-point contact self-locking structure greatly enhances the stability of the spring 4 under pressure, prevents elastic failure, and effectively transmits the elastic force to the contact point, ensuring sustained contact pressure.

[0032] The core of this application is to achieve a low-impedance, high-reliability physical connection and current conduction between two conductive components through a metal spring 4 with elastic deformation capability, focusing on solving the contact failure problem of traditional fixed grounding methods under vibration and temperature difference deformation scenarios. Compared with bolt fastening, the spring 4 compensates for assembly tolerances and dynamic displacement through its own elasticity, improving the grounding response speed by more than 30%, while simplifying the assembly process and reducing production time and costs.

[0033] In summary, the advantages of this utility model are: High reliability and vibration resistance: The spring 4 can automatically compensate for assembly tolerances and structural deformation caused by vibration, impact or temperature difference through its own elastic deformation, and always maintain stable and tight contact with the motor housing 1, effectively avoiding the problem of easy loosening of traditional rigid connection in dynamic environment, and greatly improving grounding reliability.

[0034] Low grounding impedance: The contact spring 4 and the motor housing 1 have a large area and high pressure direct metal contact, which establishes a low impedance grounding path, which is conducive to the discharge of leakage current and the stable transmission of high frequency signals, and has a positive effect on passing EMC test.

[0035] Compact structure and high space utilization: The bending angle of the spring 4 has been optimized, making it very suitable for use in micro motors with extremely limited space, and it can maintain a safe distance from surrounding components to prevent short circuits.

[0036] The assembly process is simple and suitable for automated production: the spring 4 can be fixed to the circuit board 2 by positioning through the insertion hole and surface mounting welding, which eliminates the complicated process of machining threaded holes or welding special terminals on the motor housing 1, greatly simplifying the assembly process, improving production efficiency, and reducing labor time and mold costs.

[0037] Self-locking and anti-overshoot design: The unique three-point contact structure formed by the V-shaped limit thrust section 43 and the U-shaped fixing section 41 not only enhances the rigidity and elasticity of the spring 4, but also plays the role of mechanical stop, preventing the spring 4 from being over-compressed and plastically deformed during the pressing of the end cap 3, thus ensuring its long-term performance stability.

[0038] In the description of the embodiments of this application, it should be noted that the terms "inner" and "outer" and other terms indicating direction or positional relationship are based on the direction or positional relationship shown in the drawings. This is only for the convenience of description and does not indicate or imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this application.

[0039] In the description of this application, the references to terms such as "an embodiment," "some embodiments," "in this embodiment," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0040] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A motor grounding structure, characterized in that, The device includes a motor housing (1), a circuit board (2), an end cap (3), and a spring clip (4). The spring clip (4) is mounted on the circuit board (2), and the circuit board (2) is fixed inside the motor housing (1) by the end cap (3), so that the spring clip (4) abuts against the motor housing (1). The spring clip (4) includes an integrally formed U-shaped fixing section (41), an elastic bending section (42), and a limiting thrust section (43). The lower side (411) of the U-shaped fixing section (41) is fixed to the upper end of the circuit board (2). The elastic bending section (42) bends upward and connects to the upper end of the U-shaped fixed section (41). The upper end of the limiting thrust section (43) is connected to the upper end of the elastic bending section (42), and the limiting thrust section (43) bends downward and extends the lower end of the limiting thrust section (43) to the lower side (411). When the spring sheet (4) is in a pressed contact state, the elastic bending section (42) abuts against the motor housing (1), and the lower end of the limiting thrust section (43) abuts against the lower side (411).

2. The motor grounding structure according to claim 1, characterized in that, The circuit board (2) is provided with a positioning socket (21); the lower end of the U-shaped fixing section (41) is bent downward to form an L-shaped insertion section (44), and the right angle (441) of the L-shaped insertion section (44) is a rounded transition, and the L-shaped insertion section (44) is inserted into the positioning socket (21).

3. The motor grounding structure according to claim 2, characterized in that, The outer wall of the lower side (411) of the U-shaped fixing section (41) is horizontally attached to the upper surface of the circuit board (2), and the attachment of the lower side (411) and the circuit board (2) is fixed by welding.

4. The motor grounding structure according to claim 2, characterized in that, The angle between the elastic bending section (42) and the upper side (412) of the U-shaped fixed section (41) is 135°-165°.

5. The motor grounding structure according to claim 4, characterized in that, The limiting thrust section (43) is V-shaped. The upper end of the limiting thrust section (43) is connected to the highest end of the elastic bending section (42), and the limiting thrust section (43) and the elastic bending section (42) are bent to form a U-shaped contact area (45) with the opening facing downward. The lower end of the limiting thrust section (43) is located between the lower side (411) and the upper side (412). When the spring sheet (4) is in the pressed state, the U-shaped contact area (45) is in close contact with the motor housing (1). The V-shaped point (431) of the limiting thrust section (43) is in close contact with the inner wall of the lower side (411) of the U-shaped fixing section (41). The lower end point (432) of the limiting thrust section (43) is in close contact with the inner wall of the upper side (412) of the U-shaped fixing section (41).

6. The motor grounding structure according to claim 5, characterized in that, The lower side (411) of the U-shaped fixed section (41) is integrally formed and bent upward to form a limiting plate (46); the limiting thrust section (43) is limited between the two limiting plates (46).

7. The motor grounding structure according to claim 1, characterized in that, The lower end face of the motor housing (1) is provided with a downward-facing mounting port (11); the circuit board (2) is provided with a positioning protrusion (22) located at the mounting port (11), and the positioning protrusion (22) is inserted into the mounting port (11); the spring piece (4) is installed on the positioning protrusion (22) and located in the mounting port (11). When the spring piece (4) is in a pressed state, the elastic bending section (42) is in close contact with the inner wall of the mounting port (11).

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