A doubly insulated stator structure and electric machine

Abstract

This utility model relates to the field of stator structure technology, specifically to a double-insulated stator structure and motor, including an insulation component for accommodating and covering the stator windings. The insulation component consists of a first insulating frame and a second insulating frame that cooperate with each other. When the first and second insulating frames are fastened together, they form a cavity for enclosing the stator windings within it. A positioning part is provided on the outer peripheral wall of the insulation component to ensure concentricity with the inner wall of the housing. An adhesive is filled between the positioning part and the housing. This technical solution, through the closed structure design of the double insulating frames and the spacing between the outer circular boss and the glue groove, achieves convenient production, ensures reliable insulation, and solves the problem of misalignment between the stator and the housing, thus meeting the requirements of power tools for a double-insulated structure.

Description

Technical Field

[0001] This utility model relates to the field of stator structure technology, specifically to a double-insulated stator structure and motor. Background Technology

[0002] Power tools (such as medical and electric screwdrivers) require a double insulation system, which must meet the basic insulation between the winding and the stator core, as well as the additional insulation between the stator and the housing and end cover. However, existing technologies cannot simultaneously ensure both insulation reliability and production efficiency.

[0003] Existing stator structure insulation design schemes include:

[0004] Option 1: Use an outer layer of insulating material such as polyimide tape or mica tape; however, the tape process for Option 1 is complex, which is not conducive to convenient production, and the thickness control is difficult, making it difficult to guarantee the consistency and reliability of insulation.

[0005] Option 2: Use epoxy resin to pot the space between the stator and the core to form an insulating layer; however, the epoxy potting in Option 2 has the problem of concentricity, and air bubbles and voids are prone to occur during the potting process, which cannot effectively solve the problem of additional insulation. Summary of the Invention

[0006] This invention aims to at least partially solve one of the technical problems in related technologies. Therefore, the purpose of this invention is to propose a double-insulated stator structure and motor to improve the insulation reliability of the stator structure.

[0007] The objective of this utility model can be achieved through the following technical solutions:

[0008] A double-insulated stator structure, applied between a stator winding and a housing, includes: an insulating assembly for accommodating and covering the stator winding; the insulating assembly is composed of a first insulating frame and a second insulating frame that cooperate with each other, the first insulating frame and the second insulating frame being fastened together to form an accommodating cavity for enclosing the stator winding therein; a positioning part is provided on the outer peripheral wall of the insulating assembly for concentrically engaging with the inner wall of the housing; an adhesive is filled between the positioning part and the housing to achieve insulation and concentricity control between the stator winding and the housing.

[0009] In some embodiments of this utility model, a meshing mechanism is provided between the first insulating frame and the second insulating frame, the meshing mechanism being used to detachably or non-detachably connect the first insulating frame and the second insulating frame into one unit.

[0010] In some embodiments of this utility model, the engagement mechanism includes at least one protruding tooth disposed on the first insulating frame, and a groove disposed on the second insulating frame and corresponding to the protruding tooth.

[0011] In some embodiments of this utility model, at least one contact surface of the protruding tooth and / or the groove is provided with a beveled structure to prevent the two from loosening after they are engaged.

[0012] In some embodiments of this utility model, the positioning part is at least one outer circular boss integrally formed along the outer peripheral wall of the insulating component and protruding radially outward.

[0013] In some embodiments of this utility model, the second insulating frame is provided with a winding slot for receiving the stator winding.

[0014] In some embodiments of this utility model, the outer peripheral wall of the insulating component is further provided with an adhesive groove for filling adhesive to fix the insulating component in the housing.

[0015] In some embodiments of this utility model, both the first insulating skeleton and the second insulating skeleton are integral injection molded parts of engineering plastic with high insulation strength.

[0016] An electric motor includes: a housing; a stator core; a stator winding wound around the stator core; and a stator structure with double insulation, wherein the insulating components of the stator structure cover the stator winding to form a stator winding assembly, and the stator winding assembly is fixed in the housing by a positioning part engaging with the inner wall of the housing.

[0017] In some embodiments of this utility model, an adhesive groove is provided between the outer peripheral wall of the stator winding assembly and the inner wall of the housing, and the adhesive groove is filled with adhesive to achieve a fixed connection between the stator winding assembly and the housing.

[0018] The beneficial effects of this utility model are as follows: Compared with traditional methods, this technical solution, through the double insulation skeleton combined with a closed structural design, and the structural design of the outer circular boss and glue groove, not only achieves convenient production and ensures the reliability of insulation, but also solves the problem of misalignment between the stator and the housing, thus meeting the requirements of power tools for a double insulation structure. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings.

[0020] Figure 1 This is an exploded view of the stator structure in this utility model;

[0021] Figure 2 This is a perspective view of the protruding teeth in this utility model;

[0022] Figure 3 This is a perspective view of the first insulating frame in this utility model;

[0023] Figure 4 yes Figure 3 A magnified view of a section at point A in the middle;

[0024] Figure 5 This is a perspective view of the second insulating frame in this utility model;

[0025] Figure 6 This is a three-dimensional view of the inclined plane structure in this utility model.

[0026] In the diagram: 1. First insulating frame; 2. Stator winding; 3. Second insulating frame; 4. Housing; 5. Outer circular boss; 6. Glue groove; 7. Convex tooth; 8. Inclined structure; 9. Groove. Detailed Implementation

[0027] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model. Example

[0028] like Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown in the figure, this embodiment discloses a double-insulated stator structure. Please refer to the relevant figures. This stator structure is applied between the stator winding 2 and the motor housing 4, and its core is a modular insulation component.

[0029] Detailed Structural Description: This insulation assembly consists of two pre-designed components: a first insulating frame 1 and a second insulating frame 3, which work together. During assembly, the pre-wound stator winding 2 is placed inside the second insulating frame 3. Subsequently, the first insulating frame 1 is placed on top, and the two are engaged by a specific meshing mechanism to form a completely sealed cavity, completely enclosing and sealing the stator winding 2 within it. This enclosed structure composed of the first insulating frame 1 and the second insulating frame 3 is called the stator winding assembly.

[0030] Traditional motor insulation typically relies on the insulating varnish (basic insulation) of the enameled wire itself and impregnation / potting processes. In this design, however, the solid outer shell, composed of a first insulating frame 1 and a second insulating frame 3, provides an independent, complete, and controllable layer of additional insulation beyond the stator winding 2 (which already includes basic insulation). Once this stator winding assembly is installed into the metal motor housing 4, this plastic frame forms a reliable barrier between the live parts of the stator and the housing 4 (ground), easily meeting the safety requirements for double insulation in fields such as power tools, and significantly improving product safety.

[0031] This solution replaces the traditional manual or semi-automatic tape / mica tape winding process with standardized injection-molded parts. The assembly process is simplified to two simple steps: "placing the windings and fastening the frame," significantly reducing reliance on manual skills and improving the automation level and overall production efficiency of the production line. Furthermore, because the frame is injection-molded, its insulation layer thickness is uniform, avoiding the uneven thickness problems caused by manual winding, thus ensuring product consistency and reliability.

[0032] As an example, different engineering plastics with varying properties can be selected based on the motor's operating environment and power rating. For instance, for motors operating at higher temperatures, PPS (polyphenylene sulfide) or PEEK (polyether ether ketone) materials with higher temperature resistance can be used instead of commonly used PBT (polybutylene terephthalate) or PET (polyethylene terephthalate). Glass fibers, mineral fillers, and other additives can also be added to the plastic to enhance the mechanical strength and dimensional stability of the skeleton.

[0033] As an example, wire clips and wire groove structures for leading out and fixing winding leads can be integrally injection molded on the first or second insulating frame 3, further reducing additional parts and assembly processes. Example

[0034] This embodiment focuses on describing the connection method between the first insulating frame 1 and the second insulating frame 3, such as... Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, in order to stably combine the two separate skeletons into a whole, a meshing mechanism is set between them.

[0035] As an example, the engagement mechanism is characterized by at least one protruding tooth 7 integrally formed on the edge or at a specific location of the first insulating frame 1; while at the corresponding location of the second insulating frame 3, a groove 9 is provided for receiving and locking the protruding tooth 7. To achieve more reliable locking and prevent loosening under motor vibration or impact, a bevel structure 8 is cleverly designed on the contact surface of the protruding tooth 7 and / or the groove 9.

[0036] In this embodiment, during assembly, simply align the first insulating frame 1 with the second insulating frame 3 and press down. The protruding teeth 7, utilizing their own material elasticity and the guidance of the inclined structure 8, will smoothly slide into and "lock" into the groove 9, producing a crisp sound, confirming that the installation is in place. This "snap-on" or "press-on" connection method requires no tools and is extremely simple and quick to operate.

[0037] It is important to note that the design of the inclined structure 8 is crucial. When the protruding tooth 7 enters the groove 9, a reverse wedging force is generated between the two inclined surfaces, making it difficult for the protruding tooth 7 to exit the groove 9 without the application of an external force in a specific direction. This design effectively resists the vibration generated during motor operation, ensuring the long-term structural integrity of the insulation components, thereby ensuring the continuous and stable protection of the internal stator winding 2.

[0038] As an example, in addition to the dotted protrusions 7 / grooves 9, the engagement mechanism can also be designed as a continuous or discontinuous "slot-flange" structure distributed along the edge of the skeleton to provide a more uniform locking force. Example

[0039] This embodiment aims to illustrate how the stator winding assembly is precisely installed into the housing 4 and securely fixed, such as... Figure 3 , Figure 4 , Figure 5 , Figure 6 As shown, in order to solve the problem of concentricity between the locator and the housing 4, a positioning part is provided on the outer peripheral wall of the insulating component.

[0040] As an example, the positioning part is at least one radially outwardly protruding outer circular boss 5 integrally formed on the outer circumferential wall of the second insulating frame 3 (or the first insulating frame 1). The outer diameter of the outer circular boss 5 is precisely calculated and controlled to achieve a tight fit (usually a clearance fit or a slight interference fit) with the inner wall of the motor housing 4. In addition, for final permanent fixation, a ring or multiple sections of glue grooves 6 are preferably provided on the outer circumferential wall of the insulating component.

[0041] In this embodiment, during the process of pressing the stator winding assembly into the housing 4, the outer surface of the outer circular boss 5 contacts the inner wall of the housing 4 before other parts of the assembly. Since the outer circular boss 5 is a complete ring or multiple symmetrically distributed protrusions, it plays a role in automatic centering and guidance, ensuring that the central axis of the stator winding assembly is highly aligned with the central axis of the housing 4. Precise concentricity is crucial for ensuring a uniform air gap between the motor rotor and stator, directly affecting the motor's output performance, efficiency, and operational smoothness, and effectively reducing vibration and electromagnetic noise.

[0042] It's also important to note that the glue tank 6 has a dual function. First, it provides a pre-set container for adhesives (such as epoxy glue, anaerobic glue, etc.), making the glue application process more standardized, allowing for precise control of the amount of adhesive used, and preventing glue overflow from contaminating other motor components. Second, the cured adhesive fills the space between the glue tank 6 and the inner wall of the housing 4, creating strong shear and tensile strength, firmly locking the stator winding assembly within the housing and preventing any axial or radial movement during operation. Simultaneously, this layer of adhesive further enhances insulation and thermal conductivity.

[0043] As an example, the outer circular boss 5 can be designed as a tapered surface with a slight chamfer to facilitate smoother insertion into the housing 4. For larger motors, the positioning part can also be multiple (e.g., 3 or 4) circumferentially distributed positioning blocks. Example

[0044] This embodiment describes a complete motor that includes the above-described double-insulated stator structure.

[0045] The complete motor includes a motor housing 4, and a stator and rotor installed inside the housing 4. The stator adopts the aforementioned structure, namely: the stator winding 2 is first supported by a stator core (usually made of stacked silicon steel sheets), and then this assembly is completely covered by the aforementioned insulating components (composed of a first insulating frame 1 and a second insulating frame 3) to form a stator winding assembly. Finally, the entire stator winding assembly is positioned by the outer circular boss 5 on its outer peripheral wall mating with the inner wall of the housing 4, and is finally fixed by the adhesive in the glue groove 6.

[0046] The assembly process of the motor is as follows: winding the stator winding 2 -> placing the stator winding 2 inside the second insulating frame 3 -> fastening the first insulating frame 1 to form the stator winding assembly -> injecting adhesive into the glue tank 6 -> pressing the stator winding assembly into the housing 4 -> curing the adhesive.

[0047] This complete motor solution, through its innovative stator insulation structure, achieves an excellent design that integrates high insulation reliability, high production efficiency, and high assembly precision. It fundamentally solves the three major pain points of traditional processes: low insulation reliability, poor production efficiency, and difficulty in controlling concentricity. This gives the motors, especially those used in power tools and household appliances with stringent safety and performance requirements, significant advantages in both quality and cost control.

[0048] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. 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 any suitable manner in one or more embodiments or examples.

[0049] The above description is merely an example and illustration of the present utility model. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the utility model or exceed the scope defined in the claims, they should all fall within the protection scope of the present utility model.

Claims

1. A double-insulated stator structure, applied between the stator windings and the housing, characterized in that, The device includes: an insulating assembly for accommodating and covering the stator winding; the insulating assembly is composed of a first insulating frame and a second insulating frame that cooperate with each other, and the first insulating frame and the second insulating frame are fastened together to form an accommodating cavity for enclosing the stator winding therein; a positioning part is provided on the outer peripheral wall of the insulating assembly for concentrically engaging with the inner wall of the housing; an adhesive is filled between the positioning part and the housing to achieve insulation and concentricity control between the stator winding and the housing.

2. The stator structure according to claim 1, characterized in that, The first insulating frame and the second insulating frame are provided with a meshing mechanism that cooperates with each other. The meshing mechanism is used to connect the first insulating frame and the second insulating frame into a whole in a detachable or non-detachable manner.

3. The stator structure according to claim 2, characterized in that, The engagement mechanism includes at least one protruding tooth disposed on the first insulating frame, and a groove disposed on the second insulating frame and corresponding to the protruding tooth.

4. The stator structure according to claim 3, characterized in that, At least one contact surface of the protrusion and / or the groove is provided with a beveled structure to prevent the two from loosening after they are engaged.

5. The stator structure according to claim 1, characterized in that, The positioning part is at least one outer circular boss integrally formed along the outer peripheral wall of the insulating component and protruding radially outward.

6. The stator structure according to claim 1 or 5, characterized in that, The second insulating frame has a winding slot for accommodating the stator winding.

7. The stator structure according to claim 1, characterized in that, The outer peripheral wall of the insulating component is also provided with an adhesive groove for filling adhesive to fix the insulating component to the housing.

8. The stator structure according to claim 1, characterized in that, Both the first insulating frame and the second insulating frame are integral injection molded parts made of high-insulation-strength engineering plastics.

9. An electric motor, characterized in that, include: chassis; Stator core; stator winding, the stator winding being wound around the stator core; And a double-insulated stator structure as described in any one of claims 1 to 8, wherein the insulating components of the stator structure cover the stator windings to form a stator winding assembly, and the stator winding assembly is fixed in the housing by a positioning part cooperating with the inner wall of the housing.

10. A motor according to claim 9, characterized in that, An adhesive groove is provided between the outer peripheral wall of the stator winding assembly and the inner wall of the housing. The adhesive groove is filled with adhesive to achieve a fixed connection between the stator winding assembly and the housing.

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