Spring element, stator assembly and motor assembly

Abstract

The utility model relates to a spring element, a stator assembly and a motor assembly. The spring element has a base body defining a plane and is provided with at least one projection projecting relative to the plane and at least one hook projecting obliquely from the plane, the hook and the at least one projection being arranged on opposite sides of the plane of the base body. The stator assembly comprises a stator and a plurality of the spring elements, the stator is provided with a plurality of axial grooves in the peripheral surface, and the spring elements are installed in the axial grooves. The motor assembly comprises a motor cover and the stator assembly, the stator is installed in the motor cover in an interference fit mode through the spring elements, the hook portions of the spring elements are clamped to the inner wall of the motor cover, and the protruding portions, located on the opposite sides of the plane relative to the hook portions, of the spring elements make contact with the peripheral surface of the stator. According to the utility model, the manufacturing cost is relatively low, the stator and the motor cover are relatively easy to assemble, the assembling time is relatively short, and the size of the motor cover does not need to be increased.

Description

Technical Field

[0001] The utility model relates to the field of motors, in particular to electronic power steering (EPS) motors. Specifically, in a first aspect, the utility model relates to a spring element for assembling a stator and a motor cover of the above-mentioned motor. In a second aspect, the utility model relates to a stator assembly including the spring element. In a third aspect, the utility model relates to a motor assembly including the stator assembly. Background Art

[0002] In existing motor assemblies, such as EPS motors, the stator and motor cover are usually made of ferrite magnets and aluminum, respectively. Due to the different thermal expansion coefficients of the two materials, there are problems in the assembly between the stator and the motor cover. In particular, in order to prevent the vibration generated during the operation of the motor from being transmitted to the motor cover, it is not desirable to assemble the stator into the motor cover in a direct press fit with the motor cover, which makes a gap between the stator and the motor cover appear at high motor operating temperatures, causing the stator to loosen.

[0003] Considering the above problems, the current means are to fix the stator to the motor cover by caulking or gluing. Both methods require additional equipment, resulting in increased manufacturing costs. Moreover, the caulking method may cause the stator to deform. On the other hand, the gluing method requires time for the glue to cure, resulting in longer manufacturing time. In addition, the gluing method is more suitable for mass production because the gluing machine needs to run continuously to prevent the glue from solidifying.

[0004] Figure 1 A schematic diagram of assembling a motor cover and a stator by caulking is shown, wherein caulking material S is used for caulking. Figure 2 A schematic diagram of assembling a motor cover and a stator by gluing is shown, wherein glue G is applied on the outer peripheral surface of the stator.

[0005] Figure 3 Another approach currently used is shown, in which a tolerance ring R is pressed between the stator and the motor housing. However, this approach requires the motor housing to have a larger size than intended, increasing the radial size of the motor housing and thus requiring more housing material.

[0006] CN115210992A proposes another method, which uses a spring element to fix the stator and the motor cover and play a vibration reduction role. The spring element radially protrudes from the outer peripheral surface of the stator and is installed in an axial groove provided on the outer peripheral surface of the stator in a radial shape-locking manner, and has a radial connection spring bent out of the base of the spring element and extending from the axial groove in the radial direction to abut against the inner wall of the motor cover, and an axial connection spring located on the narrow side of the base and extending from the axial groove in the axial direction to abut against the end side of the stator and the bearing cover. The spring element of this structure has high elasticity and is suitable for applications with high vibration reduction requirements. However, on the other hand, due to the structure of the spring element, the gap between the stator and the motor cover is matched, which makes it impossible to avoid the problem of a gap between the stator and the motor cover at high motor operating temperature. Summary of the invention

[0007] The purpose of the utility model is to overcome or at least alleviate the above problems existing in the prior art.

[0008] To this end, the utility model provides a spring element, which has a base body, which defines a plane and is provided with at least one protrusion protruding relative to the plane and at least one hook extending obliquely from the plane, wherein the hook and the at least one protrusion are arranged on opposite sides of the plane of the base body.

[0009] According to an exemplary embodiment, the spring element is designed as a one-piece stamped part.

[0010] According to an embodiment, the elevations are formed by punching on opposite sides of the plane of the basic body.

[0011] According to an embodiment, the hook portion is configured as a punched tongue.

[0012] According to an embodiment, the spring element has two hooks located on one side of the base, and five protuberances distributed on opposite sides of the plane of the base, wherein the two protuberances and the hooks are located on the same side. Preferably, the hooks are formed by punching holes in the protuberances located on the same side.

[0013] Preferably, the ridges on opposite sides of the plane of the substrate are arranged alternately, that is, a ridge on one side is located between two adjacent ridges on the other side, and vice versa. Preferably, the ridges are evenly spaced apart. With this arrangement, the ridges can play a spring effect.

[0014] According to an embodiment, the spring element is provided with clamping claws at both side edges, which are bent away from the hook portion from the plane of the base body. The clamping claws can be used for orientation when the spring element is mounted on the stator.

[0015] The utility model also provides a stator assembly, which comprises a stator and a plurality of the above-mentioned spring elements, wherein the stator is provided with a plurality of axial grooves on the outer peripheral surface, and the spring elements are installed in each axial groove. With this arrangement, the size of the motor cover does not need to be increased.

[0016] According to an embodiment, the axial groove is designed as a dovetail groove, into which the clamping jaws of the spring element project tangentially in order to fix the spring element in the axial groove.

[0017] According to an embodiment, 12 axial grooves are evenly arranged along the circumferential direction.

[0018] According to an embodiment, the number of spring elements can be adjusted according to the number of axial grooves on the outer peripheral surface of the stator. The length of the spring element, i.e. the axial extension, can be adjusted according to the length of the stator. The number of ridges of the spring element can also be adjusted according to the length of the stator.

[0019] The utility model also provides a motor assembly, which comprises a motor cover and the above-mentioned stator assembly, wherein the stator is installed in the motor cover in an interference fit manner through a spring element.

[0020] According to an embodiment, the hook portion of each spring element is clamped onto the inner wall of the motor cover to fix the stator in the motor cover, and the protrusion of each spring element located on the same side of the plane as the hook portion contacts the inner wall of the motor cover, and the protrusion of each spring element located on the opposite side of the plane relative to the hook portion contacts the outer peripheral surface of the stator.

[0021] The height of the spring element, that is, the distance between the ridges on opposite sides, can be adjusted according to the gap between the stator and the motor cover.

[0022] During assembly, the stator assembly with the spring element installed only needs to be pressed into the motor housing by a press-in device. Compared with the equipment required for the caulking method, the equipment cost is lower, and the stator will not be deformed during assembly. Compared with the gluing method, the assembly time is shorter. Compared with the method using tolerance rings, the size of the motor housing does not need to be increased.

[0023] Therefore, according to the utility model, the manufacturing cost is low, and the assembly of the stator and the motor cover is easy, the assembly time is short, and there is no need to increase the size of the motor cover. On the other hand, due to the structure of the spring element, the interference fit between the stator and the motor cover can avoid the occurrence of a gap between the stator and the motor cover at high motor operating temperatures, and even if a gap occurs, it is small. At the same time, due to the elastic properties of the spring element (protrusion), the vibration of the stator during the operation of the motor can be prevented from being transmitted to the motor cover to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The embodiments of the present invention will be explained in more detail in the accompanying drawings, in which:

[0025] Figure 1 is a schematic diagram of a connection arrangement between a stator and a motor cover of an example of the prior art;

[0026] Figure 2 is a schematic diagram of a connection arrangement between a stator and a motor cover of another example of the prior art;

[0027] Figure 3 is a schematic diagram of a connection arrangement between a stator and a motor cover according to another example of the prior art;

[0028] Figure 4 is a schematic diagram of the connection arrangement between the stator and the motor cover of an embodiment of the utility model;

[0029] Figure 5A-Figure 5B yes Figure 4 A detailed enlarged view of the connection arrangement in FIG.

[0030] Fig. 6A is a schematic diagram of a spring element according to an embodiment of the present utility model;

[0031] Figure 6B is another schematic diagram of a spring element according to an embodiment of the present utility model;

[0032] Figure 7 is a schematic cross-sectional view of a motor assembly according to an embodiment of the utility model;

[0033] Fig. 8A yes Figure 7 Schematic enlargement of the circled part in FIG.

[0034] Figure 8B yes Fig. 8A A schematic top view of

[0035] Fig. 9 It is a schematic top view of a motor assembly according to an embodiment of the present utility model.

[0036] In the accompanying drawings, for the sake of clarity, the embodiments of the present utility model are shown in a simplified manner. The accompanying drawings are not necessarily shown to scale. Like reference numerals in the accompanying drawings represent like components. DETAILED DESCRIPTION

[0037] Refer to the following Figure 4-Figure 9 Describe the embodiments of the present invention. In the following description, directional terms are used, which refer to the directions shown in the drawings, and the actual directions may be different.

[0038] Figure 4 1 is a stator assembly 100 according to an embodiment of the present invention, showing the connection arrangement between the stator 110 and the motor cover 200, the details of which are shown in FIG. Figure 5A and Figure 5BAs shown in the figure, the stator assembly 100 includes a stator 110 and a plurality of spring elements 120 . The stator 110 is a laminated structure, and has stator teeth (not shown) and a stator yoke 111 . Stator coils 112 are wound around the stator teeth. The stator 110 is provided with a plurality of axial grooves 113 on the outer peripheral surface, and each spring element 120 is installed in each axial groove 113 .

[0039] In this example, 12 axial grooves are evenly arranged along the circumference, and accordingly, 12 spring elements 120 are installed.

[0040] It is understood that the number of spring elements 120 can be adjusted according to the number of axial slots 113. The length, ie the axial extension, of the spring element can be adjusted according to the axial length of the stator.

[0041] Figure 6A-6B The details of the spring element 120 according to the embodiment of the utility model are shown. The spring element 120 has a base 121, which defines a plane and is provided with two hooks 122 extending obliquely from the plane and five protrusions protruding relative to the plane, wherein the protrusions are distributed on opposite sides of the plane of the base 121, wherein two protrusions 123 are located on the same side as the hooks 122, and the other three protrusions 124 are arranged on opposite sides of the plane of the base.

[0042] It is understood that the number of ridges of the spring element 120 can be adjusted according to the length of the stator.

[0043] In this example, the spring element is constructed as an integral stamped part, the protrusions 123 and 124 are formed by stamping on opposite sides of the plane of the base body 121, and the hook 122 is constructed as a stamped tongue formed by punching a hole through the protrusion 123 on the same side.

[0044] The ridges 123 and 124 are arranged alternately and are evenly spaced apart.

[0045] In addition, the spring element 120 is provided with clamping claws 125 at both side edges, which are bent away from the plane of the base body 121 and away from the hook portion 122. Figure 8B The axial groove 113 is configured as a dovetail groove, and the clamping claw 125 of the spring element 120 extends tangentially therein to fix the spring element 120 in the axial groove 113. Therefore, the clamping claw 125 can be used as an orientation when the spring element 120 is installed on the stator 110.

[0046] Figure 7-Figure 9 The motor assembly 10 according to the embodiment of the present invention is shown, which includes a stator assembly 100 and a motor cover 200 as well as a rotor assembly and a motor shaft (not shown).

[0047] like Figure 8A-8BAs shown, the hook portion 122 of the spring element 120 is clamped onto the inner wall of the motor cover 200, and the protrusion 123 of the spring element 120 located on the same side of the plane as the hook portion 122 contacts the inner wall of the motor cover 200, while the protrusion 124 of the spring element 120 located on the opposite side of the plane relative to the hook portion 122 contacts the outer peripheral surface of the stator 110, so that the stator 110 is installed in the motor cover 200 by the spring element 120 in an interference fit manner.

[0048] It is understandable that the height of the spring element 120 , that is, the distance between the protrusions 123 and 124 on opposite sides, can be adjusted according to the gap between the stator 110 and the motor cover 200 .

[0049] In some cases, the features disclosed in the present invention may be used independently of other features. On the other hand, when necessary, the features disclosed in the present invention may be combined to provide various combinations.

[0050] The words and expressions used in the present invention are illustrative rather than restrictive, and therefore the use of these words and expressions is not intended to exclude any equivalent examples of the features illustrated and described from the scope of the present invention. Various modifications, variations, and alternatives may exist within the scope of the claims. For example, the description in the specification is directed to an EPS motor, but it is understood that the present invention is also applicable to other types of motors. Therefore, the claims are intended to cover all such equivalent examples.

Claims

1. A spring element having a base body which defines a plane, characterized in that The spring element is provided with at least one protrusion protruding relative to the plane and at least one hook protruding obliquely from the plane, wherein the hook and the at least one protrusion are arranged on opposite sides of the plane of the base body.

2. The spring element according to claim 1, characterized in that The spring element is designed as a one-piece stamped part.

3. The spring element according to claim 2, characterized in that The ridges are formed by stamping on opposite sides of the plane of the base body.

4. The spring element according to claim 2, characterized in that The hook portion is configured as a stamped tongue.

5. The spring element according to any one of claims 1 to 4, characterized in that The spring element has two hooks located on one side of the plane of the base body and five ridges distributed on two opposite sides of the plane of the base body, wherein two ridges are located on the same side as the hooks.

6. The spring element according to claim 5, characterized in that The hook portion is formed by punching a hole through the raised portion on the same side.

7. The spring element according to claim 5, characterized in that The raised portions located on opposite sides of the plane of the base body are arranged alternately.

8. The spring element according to any one of claims 1 to 4, characterized in that The spring element is provided with clamping claws at both side edges, which are bent away from the hook portion from the plane of the base body.

9. A stator assembly, characterized in that: It comprises a stator and a plurality of spring elements according to any one of claims 1 to 8, wherein the stator is provided with a plurality of axial grooves on an outer peripheral surface, and the spring elements are installed in the respective axial grooves.

10. The stator assembly according to claim 9, characterized in that The axial groove is designed as a dovetail groove.

11. The stator assembly according to claim 9 or 10, characterized in that: 12 axial grooves are evenly arranged along the circumference.

12. A motor assembly, comprising a motor cover and a stator assembly according to any one of claims 9 to 11, wherein the stator is installed in the motor cover by means of spring elements in an interference fit manner, wherein the hook portion of each spring element is clamped onto the inner wall of the motor cover, and the protrusion of each spring element located on the opposite side of the plane relative to the hook portion contacts the outer peripheral surface of the stator.

13. The motor assembly according to claim 12, characterized in that The raised portion of the spring element, which is located on the same side as the hook portion, contacts the inner wall of the motor cover.

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