Motor stator and motor

Abstract

The utility model discloses a motor stator and a motor. The motor comprises a stator core and a shell, a first protrusion and a second protrusion are arranged on the outer circumferential surface of the stator core, and a groove is formed in the inner circumferential surface of the shell. A first protrusion and a second protrusion are arranged on the outer circumferential surface of a stator core, a groove is formed in the inner circumferential surface of a shell, and the first protrusion is inserted into the groove in the radial direction of the shell, so that stable circumferential connection between the stator core and the shell can be achieved through interference fit or preset clearance fit with small magnitude of interference between the first protrusion and the groove; the relative rotation of the shell and the stator core is avoided; the interference fit between the second bulge and the inner circumferential surface of the shell only needs to meet the requirement that the second bulge and the inner circumferential surface of the shell form a relatively independent cooling flow channel to supply oil liquid to directionally flow, so that the interference magnitude of the interference fit between the second bulge and the inner circumferential surface of the shell is greatly reduced; and meanwhile, the interference fit between the second bulge and the inner circumferential surface of the shell also improves the stability between the stator core and the shell.

Description

Technical Field

[0001] The utility model relates to the technical field of motors, in particular to a motor stator and a motor. Background Art

[0002] As the country's emission requirements for motor vehicles become increasingly stringent, new energy vehicles are gradually replacing traditional internal combustion engines. As the core driving component of new energy vehicles, the operating efficiency, comfort and cost-effectiveness of the drive motor have attracted much attention, among which the cooling and assembly methods of the motor are particularly important to the motor's efficiency, comfort and cost-effectiveness.

[0003] At present, oil-cooled motors are becoming the mainstream. Most of the current oil cooling technologies are centered around the stator core and end windings. The cooling oil circuit of the stator core is formed by an interference fit between the motor housing and the stator core. However, the disadvantages of this fit are also obvious, which can easily lead to the following situations:

[0004] 1. When the motor output torque is large, a larger interference fit is required to meet the output torque requirement. However, a larger interference fit will cause the stator core to be subjected to greater compressive stress, thereby reducing the efficiency of the motor.

[0005] Second, a larger interference will increase the deformation of the inner diameter of the stator core, thereby increasing the imbalance of the stator-rotor gap, further affecting the NVH performance of the motor and the comfort of the vehicle;

[0006] 3. The larger interference fit requires a higher temperature to heat the shell during the assembly process between the shell and the stator core, which increases the difficulty of the assembly process. Utility Model Content

[0007] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides a motor stator and a motor, so as to realize the stable assembly of the stator core and the housing with a small interference, and take into account the heat dissipation effect of the oil-cooled motor.

[0008] In a first aspect, the utility model provides a motor stator, comprising: a stator core, the stator core being formed by rotating and laminating a group of cores stacked axially and having equal thickness, the outer circumferential surface of the stator core being provided with a first protrusion and a second protrusion, the radial dimension of the first protrusion being greater than the radial dimension of the second protrusion;

[0009] A housing, sleeved on the outer circumference of the stator core, the inner circumference of the housing is provided with at least one groove, the groove runs through both ends of the housing in the axial direction, the first protrusion is interference fit with the groove or with a preset clearance, and all the second protrusions are interference fit with the inner circumference of the housing;

[0010] Wherein, when the stator core and the shell are assembled, any one of the first protrusions and the second protrusion adjacent thereto or the first protrusion and the inner circumferential surface of the shell together form a cooling channel; and / or, any one of the second protrusions and the second protrusion adjacent thereto and the inner circumferential surface of the shell together form a cooling channel. As is well known in the art, the radial dimensions of the first protrusion and the second protrusion are the dimensions of the protrusions in the radial direction of the rotor core, which is the comparison of the heights of the two protrusions here; through the cooperation between the first protrusion and the second protrusion and the inner circumferential surface of the shell, a channel for heat dissipation is formed to achieve a heat dissipation effect, while greatly reducing the interference between the stator core and the shell.

[0011] Furthermore, the cross-sectional shape of the groove along the direction perpendicular to the axial direction of the shell is rectangular or wedge-shaped.

[0012] Furthermore, the cross-sectional shape of the first protrusion is the same as the shape of the groove.

[0013] Furthermore, there are at least two second protrusions, which are evenly distributed on the outer peripheral surface of the stator core along the circumferential direction of the stator core.

[0014] Furthermore, there are at least two first protrusions, which are evenly distributed on the outer peripheral surface of the stator core along the circumferential direction of the stator core.

[0015] Furthermore, the number of the second protrusions between any two adjacent first protrusions is the same.

[0016] Furthermore, the number of grooves along the circumferential inner surface of the shell is the same as the number of the core groups.

[0017] Furthermore, the first protrusion and the groove are matched with a preset gap, and the value of the preset gap is 0 mm to 0.05 mm.

[0018] Furthermore, the first protrusion and the groove are interference fit, and the interference amount is a, and the interference amount between the second protrusion and the inner circumferential surface of the shell is b, where a≤b.

[0019] In a second aspect, the utility model provides a motor, comprising the motor stator as described above.

[0020] One or more of the above embodiments of the present invention have at least one or more of the following beneficial effects:

[0021] By arranging a first protrusion and a second protrusion on the outer circumferential surface of the stator core, and arranging a groove on the inner circumferential surface of the shell, the first protrusion is inserted into the groove along the radial direction of the shell, so that the first protrusion and the groove can be fitted with a small interference amount or a preset clearance fit, a stable connection between the stator core and the shell in the circumferential direction can be achieved, thereby avoiding relative rotation between the shell and the stator core; and the interference fit between the second protrusion and the inner circumferential surface of the shell only needs to satisfy the second protrusion and the inner circumferential surface of the shell to form a relatively independent cooling flow channel for directional flow of oil, thereby greatly reducing the interference amount of the interference fit between the second protrusion and the inner circumferential surface of the shell, and at the same time, the interference fit between the second protrusion and the inner circumferential surface of the shell can further improve the stability of the circumferential fixation between the stator core and the shell.

[0022] Additional aspects and advantages of the present invention will be given in part in the following description and in part will become apparent from the following description or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The disclosure of the present invention will become easier to understand with reference to the accompanying drawings. It is easy for those skilled in the art to understand that these drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present invention. In addition, similar numbers in the drawings are used to represent similar components, among which:

[0024] Figure 1 It is a schematic diagram of a connection structure between a stator and a housing of a motor provided by an embodiment of the utility model;

[0025] Figure 2 This is a front view of the connection between the stator core and the housing provided by an embodiment of the utility model;

[0026] Figure 3 It is a schematic diagram of a stator core provided by an embodiment of the utility model;

[0027] Figure 4 It is a front view of the stator core provided by an embodiment of the utility model;

[0028] Figure 5 yes Figure 4 The enlarged view of point A in the middle;

[0029] Figure 6 It is a front view of the housing provided by the embodiment of the utility model;

[0030] Figure 7 yes Figure 6 The enlarged view of point B in the middle;

[0031] Figure 8 It is a schematic diagram of a wedge-shaped groove provided in an embodiment of the utility model;

[0032] Fig. 9This is the force distribution cloud diagram of the stator core caused by the full interference fit structure used in the existing technology

[0033] Fig.10 It is a force distribution cloud diagram of the stator core of the utility model;

[0034] Fig.11 This is a cloud diagram of the deformation distribution of the stator core caused by the full interference fit structure adopted in the prior art;

[0035] Fig.12 It is a deformation cloud diagram of the stator core of the utility model.

[0036] Description of reference numerals:

[0037] 1. stator core; 2. housing; 3. groove; 4. first protrusion; 5. second protrusion; 51. cooling channel. DETAILED DESCRIPTION

[0038] Some embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0039] As described in the background technology, in current oil-cooled motors, the cooling oil circuit of the stator core is formed by an interference fit between the motor housing and the stator core, so that when the motor outputs a larger torque, a larger interference fit is required to meet the requirements. However, a larger interference fit will cause the stator core to be subjected to greater compressive stress, thereby reducing the motor efficiency.

[0040] In order to solve one or more of the above-mentioned technical problems in the prior art, the utility model creatively proposes a motor stator and a motor, wherein a first protrusion is inserted radially into a groove to achieve a circumferentially stable connection between the stator core and the shell with an interference fit with a small interference amount or a preset clearance fit; and the interference amount of the interference fit between the second protrusion and the inner circumferential surface of the shell only needs to be sufficient to form a relatively independent cooling flow channel for directional flow of oil supply liquid between the second protrusion and the inner circumferential surface of the shell, while reducing the interference amount between the second protrusion and the inner circumferential surface of the shell, the stability of the connection between the stator core and the shell can still be improved.

[0041] The present invention will be described in detail below through specific embodiments.

[0042] Example 1

[0043] Reference Figures 1 to 4As shown, this embodiment provides a motor stator, which includes a stator core 1 and a housing 2. The stator core 1 is formed by rotating and laminating a group of cores stacked in the axial direction and having equal thickness. The housing 2 is sleeved on the outer periphery of the stator core 1. The inner periphery of the housing 2 is provided with at least one groove 3, and the groove 3 runs through both ends of the housing 2 in the axial direction. The outer periphery of the stator core 1 is provided with a first protrusion 4 and a second protrusion 5, and the radial dimension of the first protrusion 4 is greater than the radial dimension of the second protrusion 5. The first protrusion 4 is interference fit with the groove 3 or with a preset clearance, and all the second protrusions 5 are interference fit with the inner periphery of the housing 2.

[0044] When the stator core 1 and the housing 2 are assembled, any first protrusion 4 and its adjacent second protrusion 5 or the first protrusion 4 together with the inner circumferential surface of the housing 2 form a cooling channel 51;

[0045] and / or,

[0046] Any second protrusion 5 and its adjacent second protrusion 5 together with the inner peripheral surface of the housing 2 form a cooling channel 51 .

[0047] It is understandable that there is no first protrusion 4 and / or second protrusion 5 in any cooling channel 51 .

[0048] By arranging the first protrusion 4 and the second protrusion 5 on the outer circumferential surface of the stator core 1, and arranging the groove 3 on the inner circumferential surface of the shell 2, the first protrusion 4 is inserted into the groove 3 along the radial direction of the shell 2, so that the first protrusion 4 and the groove 3 can be fitted with a small interference amount or a preset clearance fit to achieve a stable circumferential connection between the stator core 1 and the shell 2, thereby avoiding relative rotation between the shell 2 and the stator core 1; and the interference fit between the second protrusion 5 and the inner circumferential surface of the shell 2 only needs to satisfy the formation of a relatively independent cooling flow channel 51 between the two adjacent second protrusions 5 and the inner circumferential surface of the shell 2 for directional flow of oil, thereby the interference amount of the interference fit between the second protrusion 5 and the inner circumferential surface of the shell 2 is greatly reduced, and at the same time, the interference fit between multiple second protrusions 5 and the inner circumferential surface of the shell 2 can also further improve the stability of the circumferential fixation between the stator core 1 and the shell 2.

[0049] Preferably, the first protrusion 4 and the second protrusion 4 both extend along the circumference of the stator core 1 to the two end surfaces of the stator core to facilitate the directional flow of the oil.

[0050] Specifically, when assembling the stator core 1 and the shell 2, it is only necessary to insert a limited number of first protrusions 4 into the corresponding grooves 3 to achieve a preliminary stable connection between the stator core 1 and the shell 2. A plurality of second protrusions 5 are interference fit with the inner circumference of the shell 2 to form at least two cooling oil channels to provide a directional flow of oil, and ultimately achieve a stable connection between the stator core 1 and the shell 2.

[0051] In this embodiment, the stator core and the housing are both in the shape of hollow cylinders.

[0052] Reference Figure 4 and Figure 5 As shown, the distance between the first protrusion 4 and the axis of the stator core 1 is greater than the distance between the second protrusion 5 and the axis of the stator core 1 .

[0053] Exemplarily, the first protrusion 4 is matched with the groove 3 with a preset clearance, and the value of the preset clearance is 0 mm to 0.05 mm, which leaves more space for assembly between the stator core 1 and the housing 2, thereby reducing the difficulty of the assembly process of the stator core 1 and the housing 2.

[0054] Preferably, the first protrusion 4 is interference fit with the groove 3 to enhance the connection rigidity between the stator core 1 and the housing 2, thereby reducing the shrinkage deformation of the housing 2 and increasing the heat transfer path when the motor dissipates heat, while also increasing the transmission torque when the motor is running.

[0055] Among them, the interference fit between the first protrusion 4 and the groove 3 is a, and the interference fit between the second protrusion 5 and the inner circumferential surface of the shell 2 is b, where a≤b. The interference fit a makes it easier to assemble the stator core 1 and the shell 2, while the interference fit b improves the stability of the connection between the stator core 1 and the shell 2 and reduces the possibility of the stator core 1 moving axially along the shell 2.

[0056] In this embodiment, the stator core 1 includes a stacked core group, wherein the core group includes multiple silicon steel sheets. In order to solve the problem of uneven axial thickness of the stator core 1 caused by the thickness difference of the silicon steel sheets, multiple sections of the core group are usually placed and stacked in a certain direction. The number of the first protrusions 4 is set to be the same as the number of the core groups, thereby ensuring that each section of the core group can be tightly connected to the shell 2.

[0057] Preferably, all second protrusions 5 are evenly distributed on the outer peripheral surface of the stator core 1 along the circumference of the stator core 1, so that all cooling channels 51 can be evenly distributed along the circumference of the stator core 1, so that the oil can pass through the stator core 1 evenly, ensuring the uniformity of heat dissipation of the stator core 1.

[0058] Preferably, there are at least two first protrusions 4, which are evenly distributed on the outer peripheral surface of the stator core 1 along the circumference of the stator core 1, so that the connection force between the stator core 1 and the shell 2 is evenly distributed, thereby improving the stability of the connection between the stator core 1 and the shell 2.

[0059] Preferably, there are at least two second protrusions 5 , which are evenly distributed on the outer peripheral surface of the stator core 1 along the circumference of the stator core 1 , so that the oil is evenly distributed on the stator core 1 , thereby improving the uniformity of heat dissipation.

[0060] Furthermore, the number of second protrusions 5 between any two adjacent first protrusions 4 is the same, so that when the stator core 1 is matched with the shell 2, the force exerted on the shell 2 is evenly distributed along the circumferential direction of the outer peripheral surface of the stator core 1, thereby reducing the deformation of the shell 2.

[0061] Reference Figures 6 to 8 As shown, the cross-sectional shape of the groove 3 along the direction perpendicular to the axial direction of the housing 2 is rectangular or wedge-shaped. In this embodiment, the cross-sectional shape of the groove 3 along the direction perpendicular to the axial direction of the housing 2 is rectangular.

[0062] Furthermore, the cross-sectional shape of the first protrusion 4 along the direction perpendicular to the axial direction of the housing 2 is the same as the shape of the groove 3. In this embodiment, the cross-sectional shape of the first protrusion 4 along the direction perpendicular to the axial direction of the housing 2 is a rectangle. While facilitating the assembly of the stator core 1 and the housing 2, the pressure between the first protrusion 4 and the two inner sides of the groove 3 is equalized, further avoiding deformation of the housing 2.

[0063] In this embodiment, the first protrusion 4 and the second protrusion 5 both extend outward from the outer circumferential surface of the stator core 1 along the radial direction of the stator core 1, and are integrally formed with the stator core 1, thereby ensuring the connection strength between the first protrusion 4 and the second protrusion 5 and the stator core 1, thereby improving the connection stability between the stator core 1 and the shell 2.

[0064] Example 2

[0065] Corresponding to the above-mentioned embodiment 1, the utility model further provides a motor stator, wherein the same or similar contents as those of the above-mentioned embodiment 1 can refer to the above introduction and will not be described in detail later. In this embodiment, the material of the stator core 1 is silicon steel, and the stator core 1 is formed by 300 silicon steel sheets with a thickness of 0.25 mm stacked in the axial direction, and 48 stator slots are opened along the circumference of the inner circumference of the stator core 1, and stator teeth are formed between two adjacent stator slots. The winding is wound on the stator core 1 through the stator teeth, and part of the winding is located in the stator slot and part is located outside the stator slot.

[0066] In this embodiment, the number of the grooves 3 is 4, the number of the first protrusions 4 is 4, the number of the second protrusions 5 is 44, the interference between the first protrusions 4 and the shell 2 is 0.4 mm, and the interference between the second protrusions 5 and the shell 2 is 0.4 mm.

[0067] In this embodiment, the stator core 1 and the housing 2 are installed by the first protrusion 4 and the groove 3, and the second protrusion 5 and the inner circumferential surface of the housing 2, forming a plurality of cooling channels that penetrate the stator core 1 axially. The cooling channels are used for the flow of cooling medium, and the cooling medium is a material compatible with the copper wire and the insulating layer on the surface of the copper wire, such as oil or refrigerant; Fig. 9 This is a cloud diagram of the force distribution of the stator core caused by the full interference fit structure used in the prior art. Fig.10This is a cloud diagram of the force distribution of the stator core of the present invention. It can be seen from the diagram that the force distribution of the stator core 1 is greatly improved. Fig.11 This is the stator core deformation distribution cloud diagram caused by the full interference fit structure used in the existing technology. Fig.12 This is a deformation cloud diagram of the stator core of the present invention. It can be seen from the figure that the deformation of the stator core 1 is greatly reduced.

[0068] in, Fig. 9 and Fig.10 Equivalent (von-Mises) Stress in it means equivalent stress; Unit; MPa means the unit is megapascal; Time means time; Fig.11 and Fig.12 Total Deformation in represents the total deformation.

[0069] It should be noted that Figures 9 to 12 In order to distinguish and display the cloud maps, color illustration is used.

[0070] Example 3

[0071] Corresponding to the above-mentioned embodiments 1 and 2, the utility model also provides a motor, including a motor stator as described above; the motor also includes a rotor. This structure reduces the interference required for the stator core 1 and the housing 2 to fit together, thereby reducing the deformation of the inner diameter of the stator core 1, and further reducing the imbalance of the gap between the stator and the rotor, ultimately improving the NVH performance of the motor and the comfort of the vehicle. At the same time, the smaller interference makes it unnecessary to heat the housing 2 at too high a temperature during the assembly process of the housing 2 and the stator core 1, thereby reducing the difficulty of the assembly process. Moreover, this structure can meet the assembly requirements of the stator core 1 and the housing 2 with a smaller interference, thereby reducing the compressive stress on the stator core 1, thereby reducing the iron loss of the motor and improving the efficiency of the motor.

[0072] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0073] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0074] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A motor stator, characterized in that: The stator comprises: A stator core, wherein the stator core is formed by rotating and laminating a group of cores stacked in the axial direction and having equal thickness, and a first protrusion and a second protrusion are provided on the outer peripheral surface of the stator core, wherein the radial dimension of the first protrusion is greater than the radial dimension of the second protrusion; A housing, sleeved on the outer circumference of the stator core, the inner circumference of the housing is provided with at least one groove, the groove runs through both ends of the housing in the axial direction, the first protrusion is interference fit with the groove or with a preset clearance, and all the second protrusions are interference fit with the inner circumference of the housing; Wherein, when the stator core and the housing are assembled, any one of the first protrusions and its adjacent second protrusion or the first protrusion and the inner circumferential surface of the housing together form a cooling channel; and / or, Any one of the second protrusions, its adjacent second protrusion and the inner peripheral surface of the shell together form a cooling channel.

2. The motor stator according to claim 1, characterized in that: The cross-sectional shape of the groove along the direction perpendicular to the axial direction of the housing is rectangular or wedge-shaped.

3. The motor stator according to claim 2, characterized in that: The cross-sectional shape of the first protrusion is the same as that of the groove.

4. The motor stator according to claim 1, characterized in that: There are at least two second protrusions, which are evenly distributed on the outer peripheral surface of the stator core along the circumferential direction of the stator core.

5. The motor stator according to claim 1, characterized in that: There are at least two first protrusions, which are evenly distributed on the outer peripheral surface of the stator core along the circumferential direction of the stator core.

6. The motor stator according to claim 5, characterized in that: The number of the second protrusions between any two adjacent first protrusions is the same.

7. The motor stator according to claim 1, characterized in that: The number of the grooves along the circumferential inner surface of the shell is the same as the number of the core groups.

8. The motor stator according to any one of claims 1 to 7, characterized in that: The first protrusion and the groove are matched with each other with a preset gap, and the value of the preset gap is 0-0.5 mm.

9. The motor stator according to any one of claims 1 to 7, characterized in that: The first protrusion and the groove are interference fit, and the interference amount is a. The interference amount between the second protrusion and the inner circumferential surface of the shell is b, where a≤b.

10. An electric motor, comprising the electric motor stator according to any one of claims 1 to 9.

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