JP2017163797A - Manufacturing method of stator for electric motor and stator for electric motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of stator for electric motor capable of improving the manufacturability thereof and stator for electric motor.SOLUTION: After forming a resin layer 60 over the inner face 23i of a slot 23 by integrally forming the insulative resin layer 60 over the inner face 23i of the slot 23 of a stator core 11, a wiring 12 is inserted into the slot 23.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a method for manufacturing a stator for an electric motor and a stator for an electric motor.

Conventionally, a winding inserted into a slot of a stator core is inserted into the slot with an insulating paper interposed between the winding and the inner surface of the slot.
Here, the following Patent Document 1 discloses a winding having an inner coating made of a thermosetting resin formed around a conductive wire and an outer coating made of a thermoplastic resin formed around the inner coating. Has been. In this winding, after the winding is accommodated in the slot, the foaming agent contained in the outer coating is foamed by heat treatment to form an insulating layer having a desired thickness.

JP 2012-228093 A

By the way, when insulating paper is interposed between the winding and the inner surface of the slot, the insulating paper may be broken or crushed during the manufacture of the stator. For this reason, when providing insulating paper in a stator, the manufacturability of a stator may fall. In addition, when the insulating paper is provided, a step of cutting the insulating paper, a step of inserting the cut insulating paper into the slot, and the like are necessary. From this point of view, when the insulating paper is provided on the stator, the productivity of the stator may be lowered.
In addition, in the structure in which a double-structured film composed of an inner film and an outer film is provided on the winding and a foaming agent is included in the outer film, a process of forming a double-structured film on the winding, A step of containing a foaming agent is required. For this reason, it may be difficult to improve the manufacturability of the stator.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a method for manufacturing a stator for an electric motor and a stator for an electric motor that can improve the manufacturability.

  To achieve the above object, according to the first aspect of the present invention, in a method for manufacturing a stator for an electric motor (for example, the stator 3 in the embodiment), a slot (for example, implementation) of the stator core (for example, the stator core 11 in the embodiment). An insulating resin layer (for example, the resin layer 60 in the embodiment) is integrally formed on the inner surface of the slot 23) in the embodiment, and the resin layer is formed on the inner surface of the slot, and then the winding (for example, implementation in the slot). It is characterized by inserting a winding 12) in the form.

  In the invention described in claim 2, when the resin layer is integrally formed on the inner surface of the slot, the resin material to be the resin layer is transferred from the inner surface of the slot to the axial end surface of the stator core (for example, in the embodiment). The end surfaces 11a and 11b) are overflowed, and at least a part of the end surface adjacent to the slot is covered with a part of the resin layer.

  In the invention described in claim 3, when the resin layer is integrally formed on the inner surface of the slot, the inclined portion is inclined with respect to the insertion direction of the winding into the slot (for example, the inclined portion 83 in the embodiment). ) Is formed on the inner surface of the resin layer.

  In the invention described in claim 4, when the resin layer is integrally formed on the inner surface of the slot, the resin layer is formed of a thermosetting resin and the minimum thickness of the resin layer is 0.15 mm or more. It is characterized by doing.

  In order to achieve the above object, in the invention described in claim 5, a stator for an electric motor includes a stator core provided with a slot, an insulating resin layer provided integrally with an inner surface of the slot, and a slot. And a winding facing the resin layer.

  In the invention described in claim 6, the resin layer is an overhanging portion (for example, the overhanging portions 81 and 82 in the embodiment) that covers at least a part of the axial end surface of the stator core adjacent to the slot. It is characterized by having.

  The invention described in claim 7 is characterized in that the inner surface of the resin layer has an inclined portion inclined in a direction away from the surface of the winding as it advances in the axial direction of the stator core.

  The invention described in claim 8 is characterized in that the resin layer is made of a thermosetting resin and has a minimum thickness of 0.15 mm or more.

According to the first and fifth aspects of the present invention, since the insulating resin layer is integrally provided on the inner surface of the stator core slot, the insulating property between the stator core and the windings can be secured by this resin layer. it can. For this reason, since the trouble regarding an insulating paper does not arise at the time of manufacture of a stator, the improvement of the manufacturability of a stator can be aimed at. Further, when the insulating resin layer is integrally provided on the inner surface of the slot, the number of parts can be reduced and the number of manufacturing steps can be reduced as compared with the case where the stator core and the insulating paper are separate parts. Further, when the insulating resin layer is integrally provided on the inner surface of the slot, the resin layer is fixed to the inner surface of the slot, and therefore, the resin layer is less likely to become an obstacle in the process of inserting the winding into the slot. For this reason, compared with the case where an insulating paper is simply arrange | positioned in a slot, the favorable insertion property of the coil | winding with respect to a slot can be acquired. From this point of view, it is possible to improve the manufacturability of the stator.
In addition, when the insulating resin layer is integrally provided on the inner surface of the slot, the resin layer can be thinned because tearing and crushing of insulating paper do not occur. Thereby, the space factor in a slot can be raised and the performance improvement of an electric motor can also be aimed at.

  According to the second and sixth aspects of the invention, at least a part of the region adjacent to the slot on the axial end surface of the stator core is covered with the resin layer. Thereby, the insulation between the part located in the exterior of a slot in a coil | winding and the end surface of a slot core can be ensured more reliably. Further, when the resin layer has a portion covering the end face of the stator core, the strength of the resin layer is increased at the end of the resin layer. For this reason, even when the winding is caught in the end of the resin layer when the winding is inserted into the slot, the resin layer is hardly broken. Furthermore, if the resin layer has a portion covering the end surface of the stator core, the resin layer may be peeled off from the inner surface of the slot when the stator is cold (during cooling after the motor stops driving or during cooling of the stator). Can be suppressed.

  According to the invention described in claim 2, when the resin layer is integrally formed on the inner surface of the slot, the portion of the resin layer covering the end surface of the stator core is formed at the same time. According to such a configuration, it is possible to easily cover the end face of the stator core with a part of the resin layer while suppressing an increase in the number of manufacturing steps.

  According to the third and seventh aspects of the present invention, since the inclined portion is provided on the inner surface of the resin layer, it becomes easy to insert the winding inside the slot (inside the resin layer) by using the inclined portion as an invitation. Thereby, the productivity of the stator can be further improved.

  According to the invention described in claim 3, when the resin layer is integrally formed on the inner surface of the slot, the inclined portion of the inner surface of the resin layer is formed at the same time. According to such a configuration, the inclined portion can be easily formed on the inner surface of the resin layer while suppressing an increase in the number of manufacturing steps.

  According to the invention described in claims 4 and 8, the resin layer is formed of a thermosetting resin and the minimum thickness of the resin layer is formed to be 0.15 mm or more. According to such a configuration, cracking of the resin layer can be suppressed and insulation between the winding and the stator core can be reliably realized.

It is sectional drawing which shows the whole structure of the electric motor of 1st Embodiment. It is sectional drawing which shows a part of stator of 1st Embodiment. It is a perspective view which shows the segment coil of 1st Embodiment. FIG. 3 is an enlarged sectional view showing a region surrounded by a line F4 of the stator shown in FIG. 2. FIG. 5 is a cross-sectional view taken along line F5-F5 of the stator shown in FIG. It is sectional drawing which shows the flow of the manufacturing method of the stator of 1st Embodiment. It is sectional drawing which shows a part of stator of 2nd Embodiment. It is sectional drawing which shows the modification of the stator of embodiment.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following description, components having substantially the same or similar functions are denoted by the same reference numerals. And those overlapping descriptions may be omitted.

(First embodiment)
First, the stator 3 according to the first embodiment will be described with reference to FIGS. 1 to 6.
FIG. 1 shows an overall configuration of an electric motor (rotating electric machine) 1 including a stator 3 of the present embodiment.
The electric motor 1 is a traveling motor mounted on a vehicle such as a hybrid vehicle or an electric vehicle. However, the configuration of the present embodiment is not limited to the above example, but can be applied to a motor for power generation and motors for other purposes, and can also be applied to an electric motor (including a generator) other than that mounted on a vehicle. is there. Although the electric motor 1 of this embodiment is a distributed winding motor, for example, it is not restricted to this, A concentrated winding motor may be sufficient.

As shown in FIG. 1, the electric motor 1 includes a case 2, a stator 3, a rotor 4, and an output shaft 5.
The case 2 is formed in a cylindrical shape that houses the stator 3 and the rotor 4, for example.
The stator 3 is formed in an annular shape and attached to, for example, the inner peripheral surface of the case 2. The stator 3 includes a stator core 11 and a winding 12 attached to the stator core 11, and causes a rotating magnetic field to act on the rotor 4.
The rotor 4 includes, for example, a rotor core and a magnet attached to the rotor core, and is driven to rotate inside the stator 3.
The output shaft 5 is connected to the rotor 4 and outputs the rotation of the rotor 4 as a driving force.

  Here, the axial direction Z, the radial direction R, and the circumferential direction θ (see FIG. 2) of the stator core 11 are defined. The axial direction Z of the stator core 11 is a direction extending substantially parallel to the rotation center axis C of the output shaft 5. The radial direction R of the stator core 11 is a direction radially away from the rotation center axis C and the opposite direction (direction approaching the rotation center axis C). The circumferential direction θ of the stator core 11 is a direction that rotates around the rotation center axis C while maintaining a certain distance from the rotation center axis C.

Next, the stator 3 will be described in detail.
FIG. 2 is a cross-sectional view showing a part of the stator 3.
As shown in FIG. 2, the stator 3 includes a stator core 11, a winding 12, a slot inner surface resin layer 60 (see FIG. 4), and a slot filling and fixing portion 70 (see FIG. 4). In FIG. 2, the illustration of the slot inner surface resin layer 60 and the slot filling fixing portion 70 is omitted for convenience of explanation.

The stator core 11 is formed in an annular shape surrounding the rotor 4. The stator core 11 may be a divided stator core formed by connecting a plurality of pieces divided in the circumferential direction θ, for example, and is formed by laminating a plurality of electromagnetic steel plates in the axial direction Z. A laminated stator core may be used.
The stator core 11 has an annular yoke portion 21, a plurality of teeth portions 22, and a plurality of slots 23. The plurality of tooth portions 22 protrude from the yoke portion 21 toward the inside in the radial direction R of the stator core 11. Each slot 23 is formed between two tooth portions 22 adjacent to each other in the circumferential direction θ of the stator core 11. For this reason, the plurality of slots 23 are arranged side by side in the circumferential direction θ of the stator core 11. Each slot 23 penetrates the stator core 11 in the axial direction Z of the stator core 11.

  Each slot 23 has an inner surface (inner peripheral surface) 23 i facing the winding 12. The term “facing” as used in the present application is not limited to the case of directly facing, but also includes the case of facing with another member (for example, the resin layer 60 or the filling and fixing part 70) interposed therebetween. Further, the “inner peripheral surface” referred to in the present application means an “inner peripheral surface”. That is, the “inner peripheral surface” referred to in the present application is not limited to a continuous annular surface, and a part thereof may be interrupted.

As shown in FIG. 2, the inner surface 23i of each slot 23 has a pair of side surfaces 23a, 23b, a bottom surface 23c, and a pair of tip end surface 23d, 23e. The pair of side surfaces 23 a and 23 b are formed by different tooth portions 22 and are separated from each other in the circumferential direction θ of the stator core 11. The pair of side surfaces 23a and 23b are, for example, substantially parallel to each other. The bottom surface 23c connects the outer ends in the radial direction R of the pair of side surfaces 23a and 23b. The pair of tip end surfaces 23d and 23e extend from the inner ends of the pair of side surfaces 23a and 23b in the radial direction R so as to approach each other.
Further, the slot 23 of the present embodiment is an open slot whose inner side in the radial direction R is not closed. That is, the stator core 11 of the present embodiment has a slit 24 formed between the tip portions of the pair of tooth portions 22. The slit 24 communicates with the slot 23 in the radial direction R of the stator core 11. The width of the slit 24 in the circumferential direction θ is smaller than the width of the slot 23 in the circumferential direction θ (the distance between the pair of side surfaces 23a and 23b). The configuration of the present embodiment is not limited to this, and can be applied to a closed slot in which the inner side in the radial direction R is closed.

  The winding 12 is accommodated in the slot 23 of the stator core 11 and attached to the stator core 11. The winding 12 is a three-phase coil including a U phase, a V phase, and a W phase. The winding 12 of the present embodiment is formed by a plurality of segment coils (divided conductors) 30 that are connected to each other and used.

  FIG. 3 is a perspective view showing one segment coil 30 included in the winding 12. 3A shows the segment coil 30 that is inserted into the slot 23 and connected to another segment coil 30. FIG. FIG. 3B shows the segment coil 30 that is simply inserted into the slot 23 of the stator core 11.

  As shown in FIG. 3A, one segment coil 30 has a plurality of (for example, four) segment conductors 31. Each segment conductor 31 is a flat wire, for example. That is, the sectional shape of each segment conductor 31 is formed in a rectangular shape. The “cross section” or “cross sectional shape” referred to in the present application with respect to the winding 12 means a cross section or a cross sectional shape along a plane substantially orthogonal to the axial direction Z of the stator core 11. The plurality of segment conductors 31 inserted into the same slot 23 are stacked in one row, for example, with the main surfaces of the segment conductors 31 facing each other. Each segment conductor 31 has a conductive wire 50 and an insulating film 51 covering the conductive wire. The coating 51 is, for example, an enamel layer.

  As shown to (a) in FIG. 3, each segment conductor 31 has two linear parts 40A and 40B, the 1st connection part 41, and the 2nd connection parts 42A and 42B. The two straight portions 40A and 40B are accommodated in different slots 23. In the circumferential direction θ of the stator core 11, the straight portions 40 </ b> A and 40 </ b> B of the plurality of segment coils 30 that are accommodated separately in the plurality of slots 23 are U phase, U phase, V phase, V phase, W phase, W phase, U They are arranged in the order of phase, U phase,. The first connection portion 41 is disposed outside the slot 23 and connects the end portions of the two straight portions 40A and 40B. The second connection portions 42A and 42B are located on the opposite side of the first connection portion 41 with respect to the straight portions 40A and 40B, and are disposed outside the slot 23. One second connection portion 42A is joined to the second connection portion 42B of another segment coil 30 by TIG welding, laser welding, or the like. The other second connection portion 42B is joined to the second connection portion 42A of another segment coil 30 by TIG welding, laser welding, or the like. Thereby, the several segment coil 30 is connected sequentially.

  As shown in FIG. 3B, the segment coil 30 is inserted into the slot 23 from the outside of the stator core 11 along the insertion direction D substantially parallel to the axial direction Z of the stator core 11. Specifically, the segment coil 30 is inserted into the slot 23 with the second connection portions 42A and 42B being straight with respect to the straight portions 40A and 40B. The segment coil 30 is connected to the other segment coils 30 by bending the second connecting portions 42A and 42B with respect to the straight portions 40A and 40B after the straight portions 40A and 40B are inserted into the slots 23. In the following description, the two straight portions 40A and 40B are simply referred to as “winding portions 40” without being distinguished from each other.

Next, the slot inner surface resin layer 60 provided on the stator 3 will be described.
FIG. 4 is an enlarged cross-sectional view showing a region surrounded by line F4 of the stator 3 shown in FIG. In FIG. 4 and subsequent figures, the number of winding portions 40 in the slot 23 is schematically shown as four.

  As shown in FIG. 4, the slot inner surface resin layer 60 (hereinafter simply referred to as “resin layer 60”) is an insulating resin layer provided on the inner surface 23 i of the slot 23 of the stator core 11. The resin layer 60 forms an insulating layer that covers the inner surface 23 i of the slot 23. For example, the resin layer 60 is continuously formed across the side surfaces 23a and 23b, the bottom surface 23c, and the end portion end surfaces 23d and 23e of the inner surface 23i of the slot 23. The resin layer 60 faces the plurality of winding portions 40 accommodated in the slots 23 and electrically insulates between the plurality of winding portions 40 and the stator core 11. In the present embodiment, the resin layer 60 is formed in an annular shape along the inner surface 23 i of the slot 23 and surrounds the entire circumference of the plurality of winding portions 40. In other words, the plurality of winding portions 40 are disposed inside the resin layer 60 in the slot 23. In the present embodiment, the resin layer 60 is also provided in the slit 24 and closes the slit 24.

  In the present embodiment, the resin layer 60 is formed by being integrally formed with the inner surface 23 i of the slot 23. That is, the resin layer 60 is formed by simultaneously forming and bonding the resin layer 60 to the inner surface 23i of the slot 23 (the surface of the stator core 11) without using secondary bonding or mechanical bonding, for example. ing. For example, the resin layer 60 is formed by insert molding or the like. That is, the resin layer 60 is supplied to the inner surface 23i of the slot 23 when the stator core 11 is set inside the mold and the resin material to be the resin layer 60 is supplied to the inner surface 23i of the slot 23 in a fluid state. On the other hand, it is integrally molded. The resin material that becomes the resin layer 60 may be a thermoplastic resin or a thermosetting resin.

  As another viewpoint, the resin layer 60 is provided integrally with the inner surface 23 i of the slot 23 when viewed from the finished product of the stator 3. In the present application, “provided integrally” means that the resin member molded as a separate body is not attached later. That is, the term “provided integrally” as used in the present application means a state in which the resin layer 60 does not fall off from the inner surface 23i of the slot 23 (the surface of the stator core 11) even if there is no secondary bonding or mechanical joining. In the present embodiment, the resin layer 60 is provided along the inner surface 23 i of the slot 23 and is in close contact with the inner surface 23 i of the slot 23. In a specific example, when the resin layer 60 is formed of a thermoplastic resin, the minimum thickness t1 of the resin layer 60 with respect to the inner surface 23i of the slot 23 is 0.15 mm or more.

FIG. 5 is a cross-sectional view taken along line F5-F5 of the stator 3 shown in FIG.
As shown in FIG. 5, the resin layer 60 is provided over the entire length of the slot 23 in the axial direction Z of the stator core 11.

  Here, the stator core 11 has a first end surface 11 a and a second end surface 11 b as end surfaces in the axial direction Z of the stator core 11. The first end face 11 a is located on one side in the axial direction Z of the stator core 11 and is exposed to the outside of the stator core 11. The second end surface 11 b is located on the side opposite to the first end surface 11 a and is exposed to the outside of the stator core 11. Each of the first end surface 11 a and the second end surface 11 b is a surface that extends along the radial direction R and the circumferential direction θ of the stator core 11.

In the present embodiment, the resin layer 60 includes a main body portion 65, a first projecting portion 66, and a second projecting portion 67. The main body portion 65 is provided on the inner surface 23 i of the slot 23.
The first protrusion 66 is connected to the main body 65 and protrudes from the first end surface 11 a of the stator core 11 toward the outside of the stator core 11. The protrusion amount s1 of the first protrusion 66 with respect to the first end surface 11a of the stator core 11 is, for example, not less than the minimum thickness t1 of the resin layer 60. The protrusion amount s1 of the first protrusion 66 is, for example, 0.15 mm or more. In addition, the first projecting portion 66 has substantially the entire circumference of the inner surface 23i of the slot 23 (that is, the side surfaces 23a and 23b, the bottom surface 23c, and the tip portion of the inner surface 23i in a plan view as viewed along the axial direction Z of the stator core 11. It is formed in an annular shape along the end faces 23d, 23e).

  Similarly, the second protruding portion 67 is connected to the main body portion 65 and protrudes from the second end surface 11 b of the stator core 11 toward the outside of the stator core 11. The protrusion amount s2 of the second protrusion 67 with respect to the second end surface 11b of the stator core 11 is, for example, not less than the minimum thickness t1 of the resin layer 60. The protrusion amount s2 of the second protrusion 67 is, for example, 0.15 mm or more. In addition, the second projecting portion 67 includes substantially the entire circumference of the inner surface 23i of the slot 23 (that is, the side surfaces 23a and 23b, the bottom surface 23c, and the tip portion of the inner surface 23i in a plan view as viewed along the axial direction Z of the stator core 11. It is formed in an annular shape along the end faces 23d, 23e).

Next, the slot filling adhering portion 70 provided in the stator 3 will be described.
As shown in FIG. 4, the slot filling and fixing portion 70 (hereinafter simply referred to as “filling and fixing portion 70”) is provided inside the slot 23 of the stator core 11. The filling and fixing part 70 is formed by filling the inside of the slot 23 with an insulating material such as varnish and solidifying. The filling and fixing portion 70 fills between the plurality of winding portions 40 and the resin layer 60, and stably holds the position of the winding portion 40 in the slot 23. Further, the filling and fixing portion 70 further ensures electrical insulation between the winding portion 40 and the stator core 11.

Next, the manufacturing method of the stator 3 of this embodiment is demonstrated.
FIG. 6 is a cross-sectional view showing the flow of the manufacturing method of the stator 3. First, the stator core 11 is formed by connecting a plurality of pieces or by laminating a plurality of laminated steel plates (in FIG. 6). (See (a)). Next, the resin layer 60 is integrally formed on the inner surface 23i of the slot 23 of the stator core 11 (see (b) in FIG. 6). That is, a resin material having fluidity is supplied to the inner surface 23 i of the slot 23, and then the resin material is cooled and solidified, whereby the resin layer 60 is integrally formed on the inner surface 23 i of the slot 23. For example, the resin layer 60 is formed such that the minimum thickness t1 of the resin layer 60 is 0.15 mm or more when the resin layer 60 is integrally formed on the inner surface 23i of the slot 23.

  The resin layer 60 is formed on the inner surface 23i of the slot 23 in a state where the stator core 11 is set inside the mold, for example. At this time, since the space corresponding to the first protrusion 66 and the second protrusion 67 of the resin layer 60 is provided in the mold, the first protrusion 66 of the resin layer 60 along the internal shape of the mold. And the 2nd protrusion part 67 is formed easily and accurately.

  Then, after the resin layer 60 is formed on the inner surface 23i of the slot 23, the winding 12 (segment coil 30) is inserted into the slot 23 (see (c) in FIG. 6). For example, the plurality of segment coils 30 inserted into the plurality of slots 23 are connected to each other here.

And the insulating material (for example, varnish) which forms the filling fixed part 70 is supplied to the clearance gap between the resin layer 60 and the coil | winding 12 in the state which has fluidity | liquidity. For example, the filling material 70 is formed by heating and solidifying the insulating material (see (c) in FIG. 6).
Finally, a power connection portion for the winding 12 is attached. Thereby, the stator 3 is completed.

According to the stator 3 having such a configuration, problems relating to insulating paper do not occur when the stator 3 is manufactured. For this reason, since the insulating paper is not torn, crushed, or detached, the inspection process can be eliminated. Further, when the insulating resin layer 60 is integrally provided on the inner surface 23i of the slot 23, the number of parts is reduced and the number of manufacturing steps can be reduced as compared with the case where the stator core 11 and the insulating paper are separate parts. it can. For example, according to the integral molding, the insulating resin layer 60 can be provided on the inner surfaces 23i of the plurality of slots 23 at a time, so that it is necessary to insert insulating paper into the plurality of slots 23 one by one. In comparison, the number of manufacturing steps can be greatly reduced.
Further, when the insulating resin layer 60 is integrally provided on the inner surface 23 i of the slot 23, the resin layer 60 is fixed to the inner surface 23 i of the slot 23. Layer 60 is less likely to get in the way. For this reason, it is possible to obtain better insertability of the winding 12 into the slot 23 than in the case where the insulating paper is simply disposed in the slot 23. As a result, the productivity of the stator 3 can be improved.
Further, when the insulating resin layer 60 is integrally provided on the inner surface 23 i of the slot 23, the resin layer 60 can be made thinner because the insulating paper is not torn or crushed like insulating paper. Thereby, the space factor in the slot 23 can be raised, and the performance improvement of the electric motor 1 can also be aimed at.

  Moreover, when the minimum thickness of the resin layer 60 is formed to be 0.15 mm or more, it is possible to suppress cracking of the resin layer 60 and to reliably realize insulation between the winding 12 and the stator core 11. . For example, if the minimum thickness of the resin layer 60 is 0.15 mm or more, the insulation between the winding 12 and the stator core 11 is ensured even if there is a potential difference of about 500 V between the winding 12 and the stator core 11. Can do. When the minimum thickness of the resin layer 60 is 0.15 mm or more, it is possible to ensure good fluidity of the resin material that becomes the resin layer 60 when the resin layer 60 is integrally formed with the stator core 11.

  In the present embodiment, the resin layer 60 includes a first protrusion 66 that protrudes from the first end surface 11 a of the stator core 11 and a second protrusion 67 that protrudes from the second end surface 11 b of the stator core 11. According to such a configuration, a long wall surface distance between the winding 12 and the stator core 11 is ensured. The “wall distance” means the distance of the shortest path between the winding 12 and the stator core 11 that is not insulated. Thereby, the insulation between the coil | winding 12 and the end surfaces 11a and 11b of the stator core 11 can be ensured more reliably. Further, according to the configuration in which the resin layer 60 includes the first projecting portion 66 and the second projecting portion 67, the end surface 11 a is compared with the case where the insulating paper is protruded by a predetermined amount from the end surfaces 11 a and 11 b of the stator core 11. , 11b, the accuracy of the protrusion amount can be increased. For this reason, the management (for example, inspection) etc. of the protrusion amount with respect to end surface 11a, 11b becomes easy. Thereby, the further improvement of manufacturability of stator 3 can be aimed at.

(Second Embodiment)
Next, the stator 3 according to the second embodiment will be described with reference to FIG.
The stator 3 of the present embodiment is such that the resin layer 60 has overhang portions 81 and 82 that cover part of the end surfaces 11 a and 11 b of the stator core 11, and the inner surface 60 i of the resin layer 60 has an inclined portion 83. Different from the first embodiment. In addition, the other structure of this embodiment is the same as the structure of 1st Embodiment. Therefore, description of the same part as 1st Embodiment is abbreviate | omitted. In FIG. 7, illustration of the filling and fixing portion 70 is omitted for convenience of explanation. In FIG. 7, the inclination of the inclined portion 83 is shown more emphasized than actual.

First, the overhang portions 81 and 82 of the resin layer 60 will be described.
As shown in FIG. 7, the resin layer 60 includes a first overhang portion 81 and a second overhang portion 82.
The first overhanging portion (first covering portion) 81 is connected to the main body portion 65 and protrudes from the first end surface 11 a of the stator core 11 toward the outside of the stator core 11. The protrusion amount s1 of the first overhanging portion 81 with respect to the first end surface 11a of the stator core 11 is, for example, not less than the minimum thickness t1 of the resin layer 60. The protrusion amount s1 of the first overhang portion 81 is, for example, 0.15 mm or more.

  Further, the first overhanging portion 81 is provided along the first end surface 11 a and covers a part or the whole region of the first end surface 11 a in the axial direction Z of the stator core 11. The first overhang 81 covers at least a part of the first end surface 11a adjacent to the slot 23 (for example, an edge adjacent to the slot 23). The first projecting portion 81 has substantially the entire circumference of the inner surface 23i of the slot 23 (that is, the side surfaces 23a and 23b, the bottom surface 23c, and the end surface of the tip portion of the inner surface 23i in a plan view as viewed along the axial direction Z of the stator core 11. 23d, 23e) is formed in an annular shape (flange shape). In a specific example, the overlapping width (overlapping amount) w1 between the first projecting portion 81 and the first end surface 11a in a plan view when viewed along the axial direction Z of the stator core 11 is, for example, the minimum thickness of the resin layer 60. It is t1 or more. The overlapping width w1 of the first overhanging portion 81 is not limited to the above example.

  Similarly, the second overhanging portion (second covering portion) 82 is connected to the main body portion 65 and protrudes from the second end surface 11 b of the stator core 11 toward the outside of the stator core 11. The protruding amount s2 of the second overhanging portion 82 with respect to the second end surface 11b of the stator core 11 is, for example, not less than the minimum thickness t1 of the resin layer 60. The protrusion amount s2 of the second overhang portion 82 is, for example, 0.15 mm or more.

  The second overhanging portion 82 is provided along the second end surface 11 b and covers a part or all of the second end surface 11 b in the axial direction Z of the stator core 11. The second overhang 82 covers at least a part of the second end surface 11b adjacent to the slot 23 (for example, an edge adjacent to the slot 23). The second projecting portion 82 is substantially the entire circumference of the inner surface 23i of the slot 23 (that is, the side surfaces 23a, 23b, the bottom surface 23c, and the end surface of the tip portion of the inner surface 23i, as viewed in the axial direction Z of the stator core 11). 23d, 23e) is formed in an annular shape (flange shape). In a specific example, the overlap width (overlap amount) w2 between the second projecting portion 82 and the second end surface 11b in a plan view of the stator core 11 along the axial direction Z is, for example, the minimum thickness of the resin layer 60. It is t1 or more. Note that the overlapping width w2 of the second overhanging portion 82 is not limited to the above example.

  When the resin layer 60 is integrally formed on the inner surface 23 i of the slot 23, the first projecting portion 81 and the second projecting portion 82 allow the resin material to be the resin layer 60 to be transferred from the inner surface of the slot 23 to the first end surface of the stator core 11. 11a and the second end face 11b are overflowed, and at least a part of the first end face 11a and the second end face 11b adjacent to the slot 23 is covered with the resin material. For example, when the stator core 11 is set inside the mold and the resin layer 60 is formed on the inner surface 23i of the slot 23, spaces corresponding to the first overhanging portion 81 and the second overhanging portion 82 are provided in the die. As a result, the first projecting portion 81 and the second projecting portion 82 are easily and accurately formed along the internal shape of the mold.

Next, the inclined portion 83 of the inner surface 60i of the resin layer 60 will be described.
As shown in FIG. 7, the inner surface (inner peripheral surface) 60 i of the resin layer 60 has an inclined portion (inclined surface) 83. The inner surface 60 i of the resin layer 60 is a surface facing the winding 12 in the resin layer 60.

  The inclined portion 83 is inclined in a direction away from the surface of the winding 12 as it proceeds in the axial direction Z of the stator core 11. From another viewpoint, the inclined portion 83 is inclined with respect to the insertion direction D of the winding 12 with respect to the slot 23. The inclined portion 83 is inclined in a direction approaching the surface of the winding 12 as it proceeds in the insertion direction D. For example, the inclined portion 83 is inclined with respect to the inner surface 23 i of the slot 23.

  The inclined portion 83 is provided, for example, over the entire length of the inner surface 60 i of the resin layer 60 in the axial direction Z of the stator core 11. However, the inclined portion 83 may be provided only in a partial region of the inner surface 60 i of the resin layer 60 in the axial direction Z of the stator core 11, for example. The inclined portion 83 is provided on substantially the entire circumference of the inner surface 60i of the resin layer 60 formed in an annular shape. However, the inclined portion 83 may be provided only in a partial region in the entire circumference of the inner surface 60 i of the resin layer 60. For example, the inclined portion 83 may also serve as a draft for a mold in which the resin layer 60 is integrally formed with the stator core 11.

  From another point of view, the resin layer 60 has a first opening 85 and a second opening 86. The first opening 85 is an opening that opens from the inside of the slot 23 in the insertion direction D (downward as viewed in FIG. 7). The second opening 86 is an opening provided on the side opposite to the first opening 85 and opened from the inside of the slot 23 in the direction opposite to the insertion direction D. In the present embodiment, the opening width w4 of the second opening 86 is larger than the opening width w3 of the first opening 85.

  The inclined portion 83 is formed on the inner surface 60 i of the resin layer 60 when the resin layer 60 is integrally formed on the inner surface 23 i of the slot 23. For example, when the stator core 11 is set inside the mold and the resin layer 60 is formed on the inner surface 23i of the slot 23, the inclined portion 83 can be easily formed by providing the mold with an internal shape corresponding to the inclined portion 83. And it is formed with high accuracy.

According to the stator 3 having such a configuration, the productivity of the stator 3 can be improved as in the first embodiment.
Furthermore, in the present embodiment, by providing the first overhanging portion 81 and the second overhanging portion 82, between the portion located outside the slot 23 in the winding 12 and the end faces 11a, 11b of the stator core 11 It is possible to further ensure the insulating property. Moreover, when the 1st overhang | projection part 81 and the 2nd overhang | projection part 82 are provided, the intensity | strength of the edge part of the resin layer 60 is raised. For this reason, the crack of the resin layer 60 etc. can be suppressed at the time of insertion of the coil | winding 12 with respect to the slot 23. FIG. Here, when the stator 3 is cold or the like, the resin layer 60 may be peeled off from the inner surface 23 i of the slot 23 due to a difference in thermal expansion coefficient between the stator core 11 and the resin layer 60. However, if the first overhanging portion 81 and the second overhanging portion 82 are provided, for example, the first overhanging portion 81 and the second overhanging portion 82 sandwich the stator core 11 from both sides. Can be reliably prevented from peeling off from the inner surface 23 i of the slot 23.

In the present embodiment, since the inclined portion 83 is provided on the inner surface 60i of the resin layer 60, the inclined portion 83 is invited to facilitate the insertion of the winding 12 inside the slot 23 (inside the resin layer 60). . Thereby, the productivity of the stator 3 can be further improved.
In the present embodiment, the opening corner of the first opening 85 and the opening corner of the second opening 86 are subjected to C surface machining (45 ° chamfering), R surface machining (round chamfering), or other chamfering processing. May be. In this case, the insertion property of the winding 12 can be further improved.

  As mentioned above, although demonstrated to the stator 3 for electric motors and the manufacturing method which concern on 1st and 2nd embodiment, the structure of embodiment is not limited to the said example. For example, FIG. 7 is a cross-sectional view showing a modification of the stator 3 of the embodiment. For example, as shown in (a) of FIG. 7, the resin layer 60 may not be provided in the slit 24 of the stator core 11. Further, as shown in FIG. 7B, the stator core 11 may be a closed slot type stator core that does not have the slit 24.

  As mentioned above, although the form for implementing this invention was demonstrated using embodiment, this invention is not limited to such embodiment etc., In the range which does not deviate from the summary of this invention, various deformation | transformation and substitution are carried out. Can be added. For example, the stator to which the present invention can be applied is not limited to a specific winding type or a specific winding shape, and basically applies to all types of winding types and all types of winding shapes. Is possible.

  DESCRIPTION OF SYMBOLS 1 ... Electric motor, 3 ... Stator, 11 ... Stator core, 12 ... Winding, 23 ... Slot, 23i ... Slot inner surface, 60 ... Slot inner surface resin layer (insulating resin layer), 81 ... 1st overhang | projection part, 82 ... 2nd overhang | projection part, 83 ... Inclination part, Z ... Axial direction, R ... Radial direction, (theta) ... Circumferential direction.

Claims (8)

An insulating resin layer is integrally formed on the inner surface of the stator core slot,
After forming the resin layer on the inner surface of the slot, a winding is inserted into the slot.
A method for manufacturing a stator for an electric motor.   When integrally molding the resin layer on the inner surface of the slot, the resin material to be the resin layer overflows from the inner surface of the slot to the axial end surface of the stator core, and at least a part of the end surface adjacent to the slot The method for manufacturing a stator for an electric motor according to claim 1, wherein the region is covered with a part of the resin layer.   The inclined portion inclined with respect to the insertion direction of the winding into the slot is formed on the inner surface of the resin layer when the resin layer is integrally formed on the inner surface of the slot. The manufacturing method of the stator for electric motors of Claim 2.   2. When the resin layer is integrally formed on the inner surface of the slot, the resin layer is formed of a thermosetting resin and the minimum thickness of the resin layer is 0.15 mm or more. A method for manufacturing a stator for an electric motor according to any one of claims 1 to 3. A stator core provided with a slot;
An insulating resin layer provided integrally with the inner surface of the slot;
A winding housed in the slot and facing the resin layer;
A stator for an electric motor, comprising:   The stator for an electric motor according to claim 5, wherein the resin layer has an overhanging portion that covers at least a partial region adjacent to the slot on an end surface in the axial direction of the stator core.   7. The stator for an electric motor according to claim 5, wherein an inner surface of the resin layer has an inclined portion that is inclined in a direction away from the surface of the winding as it advances in an axial direction of the stator core.   The stator for an electric motor according to any one of claims 5 to 7, wherein the resin layer is made of a thermosetting resin and has a minimum thickness of 0.15 mm or more.

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