Stator assembly, motor and electric tool

Abstract

The utility model relates to the technical field of motors, aims to solve the technical problem that some known slot wedges and stator cores are inconvenient to assemble, and provides a stator assembly, a motor and an electric tool. The stator assembly comprises a stator core and a plurality of slot wedges. The stator core comprises an annular yoke part and a plurality of tooth parts which surround the yoke part and are arranged at intervals, and a stator groove is defined between every two adjacent tooth parts. And the plurality of slot wedges are respectively arranged at the notches of the plurality of stator slots. Wherein one of the slot wedge and the tooth part is provided with an inserting part, the other one of the slot wedge and the tooth part is provided with an inserting groove, and the inserting groove is matched in the inserting part. Along the axial direction of the stator core, the thickness of at least one end of the length direction of the plugging part is smaller than the width of the plugging groove. The beneficial effect of the utility model is that the assembling efficiency between the slot wedge and the stator core is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric machines, in particular to a stator assembly, an electric machine and a power tool. BACKGROUND

[0002] The slot opening of the stator slot of some known electric machine stators needs to be sealed, for example by injection sealing or setting a slot wedge to close. The injection sealing method can easily reduce the heat dissipation performance of the electric machine. The assembly efficiency between part of the slot wedge and the stator core is low. CONTENT OF THE UTILITY MODEL

[0003] In view of the deficiencies of the prior art, the purpose of the present application is to provide a stator assembly, an electric machine and a power tool which improve the assembly efficiency.

[0004] The present application provides a stator assembly, comprising a stator core and a plurality of slot wedges. The stator core comprises a yoke portion in the shape of a ring and a plurality of tooth portions which are arranged around the yoke portion and spaced apart from each other, and each adjacent two of the tooth portions define a stator slot. The plurality of slot wedges are respectively installed at the slot openings of the plurality of stator slots. Wherein, the slot wedge is provided with an insertion portion with one of the tooth portions, and the slot wedge is provided with an insertion slot with the other of the tooth portions, and the insertion slot is fitted in the insertion portion to close the slot opening of the stator slot. Along the axial direction of the stator core, the thickness of at least one end of the insertion portion is smaller than the width of the insertion slot.

[0005] According to the stator assembly of the present application, during the assembly of the slot wedge and the stator core, by inserting the end with smaller thickness of the insertion portion into the insertion slot, the insertion portion can be quickly and conveniently inserted into the insertion slot, improving the assembly convenience and efficiency of the slot wedge and the stator core.

[0006] In one possible implementation, along the axial direction of the stator core, the thickness of one end of the insertion portion gradually increases in the direction close to the other end.

[0007] In one possible implementation, along the axial direction of the stator core, the thickness of both ends of the insertion portion gradually increases in the direction close to the middle part of the insertion portion, and both sides of the middle part of the insertion portion abut to the two slot side surfaces of the insertion slot arranged opposite to each other.

[0008] In one possible implementation, the stator assembly further comprises a plurality of insulation pieces, and the plurality of insulation pieces are arranged one by one in the plurality of stator slots, and both ends of the insulation piece extend to both sides of the slot opening of the stator slot along the circumferential direction of the stator core.

[0009] In a possible implementation, the slot wedge comprises a wedge body and two limiting portions, the insertion portion or the insertion slot is arranged on two sides of the wedge body along the radial direction of the stator core, and the two limiting portions are respectively connected to the two sides of the wedge body along the radial direction of the stator core. The limiting portions and the tooth portions define limiting slots therebetween, and the two sides of the insulation member respectively extend into the two adjacent limiting slots.

[0010] In a possible implementation, the stator assembly further comprises a plurality of windings, and the plurality of windings are respectively wound on the plurality of tooth portions. The winding has an inner side surface close to the slot wedge along the radial direction of the stator core, and the inner side surface has a gap with the limiting portion.

[0011] In a possible implementation, the two insertion portions are arranged on two opposite sides of the slot wedge along the circumferential direction of the stator core; and each tooth portion is respectively provided with the insertion slot on two opposite sides of the tooth portion along the circumferential direction of the stator core.

[0012] In a possible implementation, the tooth portion comprises a main body portion and two extension portions, the two extension portions are respectively connected to two opposite sides of the tooth portion along the circumferential direction of the stator core, and the two extension portions extend along the circumferential direction of the stator core. Each extension portion is respectively provided with the insertion slot or the insertion portion on a side away from the main body portion.

[0013] The application further provides an electric machine comprising the foregoing stator assembly.

[0014] The application further provides an electric tool comprising the foregoing electric machine. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the application, the drawings in the embodiments will be briefly introduced as follows. It should be understood that the following drawings only show some of the embodiments of the application, and therefore should not be considered as limiting the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0016] Figure 1 FIG. 1 is a structural schematic diagram of an electric tool according to an embodiment of the application.

[0017] Figure 2 FIG. 2 is a structural schematic diagram of an electric machine according to an embodiment of the application.

[0018] Figure 3 FIG. 3 is a structural schematic diagram of a slot wedge according to an embodiment of the application.

[0019] Figure 4 FIG. 4 is a front view of the slot wedge according to an embodiment of the application.

[0020] Figure 5 Axial view of the stator core of an embodiment of the present application.

[0021] Figure 6 For Figure 5 Partial enlarged structural schematic view at I.

[0022] Figure 7 For Figure 2 Partial enlarged structural schematic view at V.

[0023] Figure 8 For Figure 7 Partial enlarged structural schematic view at VI.

[0024] Explanation of main element symbols:

[0025] Stator assembly 100 Stator core 10 Yoke portion 11 Tooth portion 12 Body portion 121 Extension portion 122 Slot wedge 20 Wedge body 21 Limiting portion 22 Plug-in portion 30 End portion 31 Middle portion 32 Insulating member 40 First insulating section 41 Second insulating section 42 Third insulating section 43 Winding 50 Stator slot C1 Plug-in slot C2 Limiting slot C3 Axial X Radial M Circumferential N First side surface P1 Second side surface P2 Slot side surface P3 Inner side surface P4 First surface P5 Second surface P6 Motor 200 Power tool 300 Machine housing 301

[0026] The following detailed description will further describe the present application with reference to the above-mentioned drawings. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application.

[0028] It should be noted that when an element is referred to as being “fixed” to another element, it can be directly on the other element or there can be an intervening element. When an element is referred to as being “connected” to another element, it can be directly connected to the other element or there can be an intervening element. When an element is referred to as being “disposed on” another element, it can be directly disposed on the other element or there can be an intervening element. The terms “vertical”, “horizontal”, “left”, “right”, and similar terms as used herein are for purposes of description only.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0030] Some embodiments of the present application are described in detail. The following embodiments and features of the embodiments can be combined with each other in the case of no conflict.

[0031] Reference is made to Figure 1The present embodiment provides an electric tool 300, which comprises a housing 301, a motor 200 and an actuator (not shown in the figure). The motor 200 is installed in the housing 301, and the motor 200 is in driving connection with the actuator to drive the actuator to move. The actuator can be configured as a blade, a grinding wheel, a clamping member for clamping a chuck, or various types of structures.

[0032] Further referring to Figure 2 The motor 200 comprises a housing (not shown in the figure), a rotor (not shown in the figure), a motor shaft (not shown in the figure) and a stator assembly 100. The motor shaft rotates with the rotor relative to the stator assembly 100 to output power to the actuator.

[0033] Further referring to Figure 2 The stator assembly 100 comprises a stator core 10 and a plurality of slot wedges 20. The stator core 10 comprises a yoke portion 11 in the shape of a ring and a plurality of tooth portions 12 arranged around the yoke portion 11 and spaced apart from each other, and each adjacent two tooth portions 12 define a stator slot C1. The axial direction X of the stator core 10 is the extension direction of the center line of the yoke portion 11. The circumferential direction N of the stator core 10 is the circumferential direction N of the yoke portion 11. The radial direction M of the stator core 10 is the radial direction M of the hole portion of the yoke portion 11. The plurality of tooth portions 12 can be connected to the inner side of the yoke portion 11 or the outer side of the yoke portion 11, or the plurality of tooth portions 12 are divided into two groups of tooth groups, one group of tooth groups is arranged on the inner side of the yoke portion 11, and the other group of tooth groups is arranged on the outer side of the yoke portion 11. In the present embodiment, the plurality of tooth portions 12 are connected to the inner side of the yoke portion 11 as an example for description.

[0034] Further referring to Figures 3 to 6 The plurality of slot wedges 20 are respectively installed at the slot openings of the plurality of stator slots C1. The slot wedge 20 is provided with an insertion portion 30 at one of the tooth portions 12, and the slot wedge 20 is provided with an insertion slot C2 at the other one of the tooth portions 12, and the insertion slot C2 is fitted into the insertion portion 30 to close the slot opening of the stator slot C1. In the axial direction X of the stator core 10, the thickness of at least one end of the insertion portion 30 is less than the width of the insertion slot C2. The thickness of the insertion portion 30 is the distance between the two surfaces of the insertion portion 30 arranged in opposite directions along the radial direction M of the stator core 10, and the width of the insertion slot C2 is the distance between the two sides of the insertion slot C2 arranged in opposite directions along the radial direction M of the stator core 10.

[0035] According to the stator assembly 100 of the present embodiment, in the assembling process of the slot wedge 20 and the stator core 10, by inserting the end with smaller thickness of the insertion portion 30 into the insertion slot C2, the insertion portion 30 can be quickly and conveniently inserted into the insertion slot C2, and the assembling convenience and efficiency of the slot wedge 20 and the stator core 10 are improved.

[0036] In some embodiments, referring to Figure 3The thickness of the one end of the insertion portion 30 gradually increases in the direction close to the other end along the axial direction X of the stator core 10. In this way, the insertion groove C2 can guide the movement of the insertion portion 30 during the cooperation of the insertion portion 30 and the insertion groove C2, so as to further improve the assembly accuracy.

[0037] In some embodiments, referring to Figure 3 The thickness of the end portion 31 of the two ends of the insertion portion 30 gradually increases in the direction close to the middle portion 32 of the insertion portion 30 along the axial direction X of the stator core 10, and the two sides of the middle portion 32 of the insertion portion 30 abut to the two groove side surfaces P3 of the insertion groove C2 arranged oppositely. In this way, during the installation of the slot wedge 20 on the stator core 10, the end portion 31 of the insertion portion 30 can be smoothly inserted into the insertion groove C2 until the middle portion 32 of the insertion portion 30 contacts the groove side surface P3 of the insertion groove C2, and then continue to move the slot wedge 20 and the stator core 10 along the axial direction X until the two end portions 31 of the insertion portion 30 correspond to the two ends of the insertion groove C2. After the middle portion 32 of the insertion portion 30 corresponds to the middle portion 32 of the insertion groove C2, the middle portion 32 of the insertion portion 30 can abut to the groove side surface P3 of the insertion groove C2, so as to ensure the stability of the insertion between the slot wedge 20 and the stator core 10, reduce the possibility of axial X relative displacement between the slot wedge 20 and the stator core 10, and improve the assembly quality between the slot wedge 20 and the stator core 10.

[0038] Specifically, the insertion portion 30 can be formed in the structure of thin at both ends and thick in the middle by a processing mode of stripping.

[0039] In other embodiments, the thickness of the insertion portion 30 can also be distributed in a stepped increasing manner from the two ends to the middle portion 32 along the axial direction X of the stator core 10.

[0040] In some embodiments, referring to Figure 4 The insertion portion 30 has a first side surface P1 and a second side surface P2 distributed along the radial direction M of the stator core 10. Referring to Figure 6 The insertion groove C2 includes two groove side surfaces P3 arranged oppositely along the radial direction M of the stator core 10. The first side surface P1 and the groove side surface P3 close to it have a first spacing. The second side surface P2 and the groove side surface P3 close to it have a second spacing. The first spacing and the second spacing are substantially equal, so as to further facilitate the insertion cooperation of the slot wedge 20 and the stator core 10.

[0041] In some embodiments, referring to Figure 4 The two insertion portions 30 are arranged on the two sides of the slot wedge 20 opposite along the circumferential direction N of the stator core 10. Referring to Figure 6Each tooth portion 12 is provided with a plug-in groove C2 on each side along the circumferential direction N of the stator core 10. During assembly, the stator core 10 can be controlled to remain fixed, and then the slot wedge 20 is installed. In this way, the plug-in portion 30 on the slot wedge 20 is matched with the plug-in groove C2 on the stator core 10, which is more convenient.

[0042] In some embodiments, referring to Figure 6 The width of the plug-in groove C2 along the radial direction M of the stator core 10 is the same along the axial direction X of the stator core 10.

[0043] In another embodiment, the slot wedge 20 is provided with a plug-in portion 30 and a plug-in groove C2 on each side along the circumferential direction N of the stator core 10. The tooth portion 12 is provided with a plug-in portion 30 and a plug-in groove C2 on each side along the circumferential direction N of the stator core 10. Specifically, along the circumferential direction N of the stator core 10, the plug-in portion 30 and the plug-in groove C2 are alternately distributed on the plurality of slot wedges 20; the plug-in portion 30 and the plug-in groove C2 are alternately distributed on the plurality of tooth portions 12.

[0044] In another embodiment, one side of the slot wedge 20 along the circumferential direction N of the stator core 10 is matched with one tooth portion 12 along the circumferential direction N of the stator core 10 through the plug-in portion 30 and the plug-in groove C2, and the other side of the slot wedge 20 along the circumferential direction N of the stator core 10 is matched with another tooth portion 12.

[0045] In some embodiments, along the radial direction M of the stator core 10, the number of plug-in portions 30 and plug-in grooves C2 is one. In this way, it can be ensured that the plug-in portion 30 and the plug-in groove C2 still have a certain size on the smaller size stator assembly 100, avoiding the problem of poor plug-in reliability caused by the too small size of the plug-in portion 30, thereby ensuring the plug-in reliability of the plug-in portion 30 and the plug-in groove C2. In other embodiments, the number of plug-in portions 30 and plug-in grooves C2 can be set to two or more, and are spaced apart along the radial direction M of the stator core 10.

[0046] In some embodiments, referring to Figure 5 and Figure 7The motor 200 further comprises a plurality of windings 50. The number of the windings 50 is the same as the number of the tooth portions 12. The tooth portion 12 comprises a main body portion 121 and two extension portions 122. The main body portion 121 is configured to wind the winding 50. The two extension portions 122 are respectively connected to two sides of the tooth portion 12 along the circumferential direction N of the stator core 10, and extend along the circumferential direction N of the stator core 10. Each of the extension portions 122 is provided with a plug-in groove C2 or a plug-in portion 30 on a side away from the main body portion 121. In the embodiment, the side of the extension portion 122 away from the main body portion 121 is provided with the plug-in groove C2. In this way, the slot opening of the wire slot is defined between the mutually approaching extension portions 122 of the two adjacent tooth portions 12. By providing the extension portion 122, the slot opening width of the wire slot can be reduced, thereby reducing the size of the slot wedge 20 along the circumferential direction N of the stator core 10, and further reducing the possibility of the slot wedge 20 shaking off and improving the assembly stability between the slot wedge 20 and the tooth portion 12.

[0047] In some embodiments, referring to Figure 7 and Figure 8 , the stator assembly 100 further comprises a plurality of insulation pieces 40. The plurality of insulation pieces 40 are provided in the plurality of stator slots C1 one by one. The two ends of the insulation piece 40 extend to two sides of the slot opening of the stator slot C1 along the circumferential direction N of the stator core 10, and abut to two sides of the slot wedge 20 along the circumferential direction N of the stator core 10. In this way, the slot wedge 20 cooperates with the insulation piece 40 to insulate the winding 50 and the stator core 10, and increase the creepage distance.

[0048] In some embodiments, the insulation piece 40 is insulation paper. The insulation paper can achieve reliable insulation effect and prevent the enameled wire of the winding 50 from being scratched by the nail core.

[0049] In some embodiments, referring to Figure 7 and Figure 8 , the slot wedge 20 comprises a wedge body 21 and two limiting portions 22. The plug-in portion 30 or the plug-in groove C2 is provided on two sides of the wedge body 21 along the radial direction M of the stator core 10, and the two limiting portions 22 are respectively connected to two sides of the wedge body 21 along the radial direction M of the stator core 10. The limiting portion 22 and the tooth portion 12 define a limiting slot C3, and the two sides of the insulation piece 40 respectively extend into the two adjacent limiting slots C3. In this way, the limiting slot C3 can limit the insulation piece 40, thereby improving the installation reliability of the insulation piece 40 in the stator slot C1.

[0050] In some embodiments, referring to Figure 7 , along the radial direction M of the stator core 10, the limiting portion 22 is located outside the plug-in portion 30 and in the stator slot C1.

[0051] In other embodiments, the wedge 20 can be provided with a matching structure on both sides of the radial direction M of the stator core 10, and the matching structure is matched with the insulating piece 40, so that the insulating piece 40 is matched with the wedge 20. Alternatively, the insulating piece 40 can be provided in a closed annular structure and arranged on the inner side of the wedge 20. Therefore, there are various structures for matching the insulating piece 40 with the wedge 20, and the embodiments will not be described hereinafter.

[0052] In some embodiments, referring to Figure 7 , the insulating piece 40 includes a first insulating section 41, two second insulating sections 42, and two third insulating sections 43. The first insulating section 41 is attached to the yoke 11. The two second insulating sections 42 are connected to the first insulating section 41 on both sides of the circumferential direction N of the stator core 10 and are attached to the main body 121 of the two adjacent tooth portions 12, respectively. The two third insulating sections 43 are connected to the two second insulating sections 42, respectively, and are attached to the extension 122 of the two adjacent tooth portions 12, respectively. The ends of the two third insulating sections 43 away from the second insulating sections 42 extend into the two limiting grooves C3, respectively.

[0053] In some embodiments, referring to Figure 8 , the winding 50 has an inner side P4 close to the inner side P4 of the wedge 20 along the radial direction M of the stator core 10, and the inner side P4 and the limiting portion 22 have a gap therebetween. In this way, during the installation of the wedge 20, the limiting portion 22 is not easy to scratch the winding 50, so as to ensure the integrity of the winding 50 and improve the assembly quality of the stator assembly 100. At the same time, the gap can further ensure the separation between the winding 50 and the stator core 10, improve the insulation protection effect, reduce the risk of short circuit, energy loss and safety hazard, and improve the working safety of the motor 200.

[0054] In the embodiments, the winding 50 is wound on the main body 121 of the tooth portion 12 by an enameled wire.

[0055] In some embodiments, referring to Figure 8 , the limiting portion 22 has a first surface P5 and a second surface P6 arranged opposite to each other along the radial direction M of the stator core 10, the first surface P5 and the tooth portion 12 define the limiting groove C3, the first surface P5 is attached to the insulating piece 40, the second surface P6 is located on the side of the first surface P5 outward along the radial direction M of the stator core 10, and the second surface P6 is located in the direction away from the wedge body 21. The distance between the second surface P6 and the first surface P5 gradually decreases, and the second surface P6 and the inner side P4 have a gap therebetween.

[0056] Since the winding 50 is wound on the main body portion 121, a part of the winding 50 extends into the stator slot C1, so that the overlap between the wedge body 21 of the slot wedge 20 and the winding 50 is less, and the overlap between the limiting portion 22 and the winding 50 along the radial direction M of the stator core 10 is more. By gradually reducing the spacing between the second surface P6 and the first surface P5, the size of the limiting portion 22 along the radial direction M of the stator core 10 is gradually reduced, so that the first surface P5 and the inner side surface P4 form a gap at each position in the circumferential direction N of the stator core 10. In this way, without adjusting the structure of the extension portion 122 of the tooth portion 12, the extension portion 122 is prevented from being offset inwardly along the radial direction M of the stator core 10, so that the inner side space of the stator core 10 is not occupied, and the space utilization of the stator assembly 100 is improved.

[0057] In other embodiments, the spacing between the first surface P5 and the second surface P6 along the circumferential direction N of the stator core 10 can also be kept constant, and by changing the structure of the extension portion 122, the first surface P5 and the second surface P6 are both offset inwardly along the radial direction M of the stator core 10, so that a gap can also be formed between the second surface and the inner side surface P4.

[0058] Specifically, the limiting slot C3 is defined between the first surface P5 and the extension portion 122 of the tooth portion 12, and the first surface P5 is attached to the third insulation section 44 of the insulation piece 40.

[0059] In some embodiments, referring to Figure 8 , the first surface P5 is a plane, and the second surface P6 is an arc surface.

[0060] The above embodiments are only used to illustrate the technical solutions of the present application and not to limit the present application. Although the present application has been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the present application.

Claims

1. A stator assembly, characterized in that, include: A stator core, the stator core including an annular yoke and a plurality of teeth arranged around the yoke and spaced apart from each other, wherein a stator slot is defined between two adjacent teeth; as well as Multiple slot wedges are respectively installed at the openings of multiple stator slots; Wherein, one of the slot wedge and the tooth is provided with an insertion part, and the other of the slot wedge and the tooth is provided with an insertion groove. The insertion part is engaged with the insertion groove so that the slot wedge is installed into the stator slot, and the slot wedge closes the opening of the stator slot. Along the axial direction of the stator core, the thickness of at least one end of the insertion portion is not greater than the width of the insertion slot.

2. The stator assembly according to claim 1, characterized in that: Along the axial direction of the stator core, the thickness of one end of the plug gradually changes in the direction approaching the other end.

3. The stator assembly according to claim 2, characterized in that: Along the axial direction of the stator core, the thickness of both ends of the plug portion gradually increases in the direction near the middle of the plug portion, and the two sides of the middle of the plug portion respectively abut against the two opposite sides of the plug slot.

4. The stator assembly according to claim 1, characterized in that: The stator assembly also includes a plurality of insulating components, which are disposed one-to-one in a plurality of stator slots, with both ends of the insulating components extending to the slot openings of the stator slots along both sides of the stator core circumferentially.

5. The stator assembly according to claim 4, characterized in that: The slot wedge includes a wedge body and two limiting portions. The insertion portion or the insertion groove is provided on both sides of the wedge body along the circumference of the stator core. The two limiting portions extend from the wedge body along the circumference of the stator core to both sides respectively. The limiting portion and the tooth portion define a limiting groove. The two sides of the insulating member extend into the two adjacent limiting grooves respectively.

6. The stator assembly according to claim 5, characterized in that: The stator assembly further includes multiple windings, which are wound one-to-one on multiple teeth. Each winding has an inner side surface that is radially close to the slot wedge of the stator core, and there is a gap between the inner side surface and the limiting part.

7. The stator assembly according to any one of claims 1 to 6, characterized in that: The two insertion portions are located on opposite sides of the slot wedge along the circumference of the stator core; Each of the teeth is provided with a insertion slot on opposite sides of the stator core along the circumferential direction.

8. The stator assembly according to any one of claims 1 to 6, characterized in that: The toothed portion includes a main body and two extensions. The two extensions are respectively connected to both sides of the toothed portion along the circumference of the stator core. The two extensions extend along the circumference of the stator core. Each extension is provided with a insertion slot or insertion part on the side away from the main body.

9. An electric motor, characterized in that, Includes the stator assembly as described in any one of claims 1 to 8.

10. A power tool, characterized in that, Includes the motor as described in claim 9.

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