WO2018168649A1

WO2018168649A1 - Motor stator

Info

Publication number: WO2018168649A1
Application number: PCT/JP2018/009025
Authority: WO
Inventors: 友彰貝森; 隆平西田; 真崇早乙女
Original assignee: 日産自動車株式会社; 株式会社ニフコ
Priority date: 2017-03-15
Filing date: 2018-03-08
Publication date: 2018-09-20
Also published as: JP2018153050A

Abstract

A motor stator comprising segment cores segmented from a stator core and coils wound around the outer peripheries of the segment cores across a resin insulator, wherein the insulator is formed on outer peripheral parts of the segment cores by means of insert molding, and a burr-relief recessed part is disposed at a section encompassing a parting line at the time of insert molding.

Description

Motor stator

The present invention relates to a stator for a motor.

8 (a) to 8 (c) are cross-sectional views of the motor disclosed in Patent Document 1 in the radial direction. In FIG. 8A, a stator (stator) 31 is provided on the inner peripheral side of the housing 20, and a rotor (rotor) 40 that is rotated via a rotation shaft 43 is disposed on the inner side. The rotor 40 is rotated by receiving a rotating magnetic field from the stator 31. Here, the stator 31 is a type in which the yoke portion and the tooth portion are divided. The yoke portion is composed of a cylindrical yoke core 33 in which a plurality of annular magnetic bodies are laminated in the axial direction. The teeth portion is divided from the yoke core 33, and a plurality of teeth portions are arranged at predetermined intervals in the circumferential direction, and are configured from a tee score 34 in which one end in the radial direction is fitted to the inner circumferential portion of the yoke core 33. . Each tee score 34 has a structure in which a plurality of magnetic bodies are laminated like the yoke core 33, and is wound around the outer periphery via a resin insulator (slot insulation) 36 as shown in FIG. 8 (b). And a coil (winding) 32a.

In the above structure, the insulator 36 is formed on the outer periphery of the tea score 34 by insert molding. In this structure, as the thickness of the insulator 36, the portion where the coil 32 a is wound, that is, the thickness of the winding winding portion 34 i, the front end side flange portion (front end side winding frame portion) 36 b, the rear end side flange portion (yoke core) The thermal resistance is reduced by forming it to be thinner than the fastening part side frame part) 36c, preferably about 0.2 to 0.3 mm. In addition, in the winding portion 34i of the tee core, a groove portion 34n that makes the radial position different between one surface and the other surface is provided on two surfaces facing each other on the surface where the coil is wound. Thus, it is possible to prevent short shot and swelling of the resin during resin insert molding.

FIG. 8 (c) shows a molding die used in the insert molding method. This structure has at least an upper mold 50, a lower mold 53, and two

slide molds

51, 52, and the tea score 34 is fixed to the lower mold 53, and the slide mold 51, so as to sandwich the tea score 34 from both sides. 52, the

slide molds

51, 52 are pressed by the upper mold 50 in the lower mold direction, and the

slide molds

51, 52 are moved in a direction orthogonal to the pressing direction so as to be close to each other. In addition, the

slide molds

51 and 52 are brought into close contact with each other, and an insulating resin is injected into a gap formed between them and the tea score 34 to cure the insulating resin.

Japanese Patent No. 3791492

In the above-described insert molding, in particular, the slide mold is closely contacted with the winding portion of the tee core while maintaining a predetermined gap, and the molten resin is set to the gap, that is, the cavity, from the gate to the set inflow speed and pressure. However, there is a possibility that the molten resin flows into the parting gap (clearance) and burrs are generated. When the burr is formed on the contact surface of the coil, the coil cannot be wound with high accuracy, and the position is easily displaced during winding.

As countermeasures, burr generation is mainly affected by molding pressure, mold temperature, and injection speed. For example, burr generation can be minimized by setting the resin temperature higher or setting the injection pressure (holding pressure) lower. It does not occur. However, it is difficult to completely prevent this burr due to the occurrence of wear and distortion caused by variations in molding conditions and long-term use of the mold. At the manufacturing site, burrs are corrected by inspecting whether or not burrs are generated after molding, but in some cases, high-precision stators cannot be deburred.

SUMMARY OF THE INVENTION An object of the present invention is to provide a stator structure in which an insulator is formed by insert molding on the outer peripheral portion of a core, and a coil can be wound stably and accurately without being affected by the occurrence of burrs during molding. Is to provide. Other objects will be clarified in the following description.

In order to achieve the above object, according to one aspect of the present invention, there is provided a divided core obtained by dividing a stator core, and a motor stator in which a coil is wound around an outer peripheral portion of the divided core via a resin insulator. In addition to being formed by insert molding on the outer periphery of the split core, it has a burr escape recess provided at a location including a parting line (PL) during insert molding.

The present invention includes the following aspects.
(A) The insulator has a configuration in which a winding surface around which the coil is wound is an outer periphery having a substantially rectangular cross section, and the recess is located at a corner of the rectangle. According to this aspect, in the structure in which the coil winding surface has an outer periphery with a substantially rectangular cross section, when the insulator has the hollow portion formed at the rectangular corner, the slide mold configuration in the molding die can be easily simplified, and the coil winding Make it possible to perform the turning operation well.
(B) The insulator has a winding surface on which the coil is wound, and front and rear flange portions rising from the front and rear ends of the winding surface, and the hollow portion is an inner peripheral surface of the flange portion together with the winding surface. It is the structure provided in a part of. According to this aspect, the coil is wound so as to fit in the partition portion between the winding surface and the front and rear flange portions, but the dent portion is provided on a part of the inner peripheral surface of the flange portion together with the winding surface, thereby temporarily inserting Even if burrs are generated on the inner peripheral surface of the flange portion by molding, the coil is absorbed so that the coil does not come into contact with the burr edge at the recessed portion which is one step lower on the inner peripheral surface of the flange portion, and the winding operation can be performed with high accuracy.

(C) The recess portion provided in the flange portion is configured to be positioned at a rectangular corner of the flange portion. According to this aspect, when the hollow portion is formed at the rectangular corner portion of the flange portion together with the winding surface on which the coil is wound, the slide mold configuration in the molding die can be simplified.
(D) The insulator has a guide groove on the outer periphery of the substantially rectangular cross section that is the winding surface, and is formed in an outer peripheral portion sandwiching the corners of the rectangle to guide the coil in the winding direction. It is the composition which is. The guide groove has a shape that allows the coil to be received and positioned in the radial direction, and may be provided at least on both sides of the corner portion of the winding surface. Moreover, you may provide a guide groove also between a corner | angular part. According to this aspect, since the insulator has the guide groove that is formed in the outer peripheral portion sandwiching the rectangular corner portion and guides the coil in the winding direction, the coil winding operation is reliably prevented in the coil winding operation. To prevent.

In the present invention, in a stator for a motor in which an insulator is formed on the outer periphery of the core by insert molding, even if burrs are generated by insert molding, a part including PL that is a burr generation part is lowered one step from the coil winding surface. By forming it in a hollow, that is, a step or recess, and keeping the burr edge away from the coil winding surface, it is possible to wind the coil stably and accurately without being affected by the occurrence of burr during molding, improving yield. Furthermore, it can contribute to the improvement of the motor output.

(A) And (b) is the schematic perspective view which looked at the external appearance of the division | segmentation core (a coil is abbreviate | omitted) of invention form from the different direction. (A) is the elements on larger scale which show in the state where hatching was given to the hollow part for burr escape in the split core of Drawing 1, and (b) is the elements on larger scale which show (a) in the state where it turned upside down. The details of the split core are shown, (a) is a rear end view, (b) is a top view, and (c) is a front end view. (A) is a left end view of the split core of FIG. 3, and (b) and (c) are schematic diagrams for explaining the action when winding a coil. 3A is a cross-sectional view taken along line AA in FIG. 3A, FIG. 3B is a cross-sectional view taken along line BB in FIG. 3B, and FIG. 3C is a cross-sectional view taken along line CC in FIG. It is. It is explanatory drawing which shows typically the shaping die used for insert molding corresponding to the cross section of Fig.5 (a). FIG. 7 is a schematic cross-sectional view taken along the line DD in FIG. 6. (A) shows a motor structure disclosed in Patent Document 1, (b) shows a split core, and (c) is a schematic diagram showing a molding die used for insert molding.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. 1 to 5 show a split core constituting the motor stator of the present invention, and FIGS. 6 and 7 show a molding die for forming an insulator in the split core. In the following description, after clarifying the stator structure for a motor, the molding method and advantages will be mentioned.

(Stator Structure) In FIGS. 1 (a) to 5 (c), the motor stator is constituted by a plurality of divided cores 1 in which the stator core is divided as in FIG. 8 (a). Each of the split cores 1 is a type integrally including a teeth portion 10 and a yoke portion 11 as shown in FIGS. 4 (a) to 4 (c) and FIGS. 5 (a) to 5 (c). The coil 3 is wound around the part via a resin insulator 2.

Further, the split core 1 uses a core material having teeth-corresponding portions and yoke-corresponding portions by punching a magnetic steel sheet into a substantially T-shape, and by joining means such as laser welding in a state where a predetermined number of the core materials are laminated. It is made by joining together. In each figure, the outline or laminated structure of the core material is omitted. In the split core 1, two surfaces in a direction facing a rotor (not shown) are referred to as a front end surface or a rear end surface, and two surfaces in a direction intersecting the front rear end surface (rotation direction of the rotor) are a left side surface or a right side surface. The remaining two surfaces facing each other are referred to as an upper surface or a lower surface.

First, the tooth portion 10 has a tip surface 12 protruding to the rotor (not shown) side formed in a substantially flat surface, and has an overhang portion 13 formed around the front side of the tip surface 12. . The overhang portion 13 protrudes in the left and right directions, which are the rotor rotation direction (not shown).

The yoke portion 11 is a circular arc surface having a loose rear end surface that is an outer periphery, a concave portion 14 provided in the middle of the circular arc surface, a concave portion 15 provided on one of the left and right side surfaces (right side in this example), and It has a projection 16 provided on the other side (left side in this example). The recess 14 is used when the split core 1 is disposed in an insulator molding die described later, or when the split core 1 is disposed inside a motor housing (not shown). The concave portion 15 and the convex portion 16 have shapes that can be engaged with each other as shown in FIG. 4C, and are used when the divided cores 1 are connected to each other.

The insulator 2 is made of PPS (polyphenylene sulfide) resin having high insulation and heat resistance by insert molding on the outer peripheral portion constituting the split core 1, that is, the outer periphery of the teeth portion 10 and the inner end face of the yoke portion 11. It is formed and has burr escape recesses 23 and 24 provided at locations including the parting line (PL) at the time of insert molding.

More specifically, the insulator 2 has a cylindrical outer periphery with a winding surface 20 where the coil 3 is wound as shown in FIGS. 5 (a) to 5 (c). The front and

rear flange portions

22 and 21 are further raised, and a coil winding space, that is, a winding space corresponding to a bobbin, is partitioned by the winding surface 20 and the front and

rear flange portions

22 and 21. The front and

rear flange portions

22 and 21 are usually formed so that each flange portion is thicker than the thickness of the winding surface 20 as illustrated in FIG. Further, as illustrated in FIG. 4C, the front flange portion 22 is formed to be smaller in diameter than the rear flange portion 21 from the number of windings and the winding distribution of the coil 3 on the winding surface 20.

Here, in the winding surface 20, substantially four V-shaped depressions 23 are formed at the four corners, as shown in FIG. 5C, at locations or sizes including PL during insert molding. The depth of each recess 23 is set such that even if burrs occur during insert molding, the dimensions do not affect the winding operation when the coil 3 is wound, that is, the coils 3 do not contact the burrs.

As shown in FIGS. 3 (a) to 3 (c), the rear flange portion 21 has two

corner portions

21a and 21a formed on a plate portion having a continuous right side, whereas the left side has two

corner portions

21a and 21a. The space between 21 a is cut out and the outer surface side is formed in the thick portion 26. On the other hand, as for the front flange part 22, right and left are the same shape, and all have notched between two corner |

angular parts

22a and 22a.

In each corner 21a and corner 22a, on the inner surfaces facing each other, as shown in FIGS. 2 (a) and 2 (b), there are recessed

portions

28 and 29 each having a size or a portion including PL at the time of insert molding. Is formed. The depths or steps of the

recesses

28 and 29 are set such that even if burrs occur during insert molding, the dimensions do not affect the winding operation when the coil 3 is wound, that is, the coils 3 do not contact the burrs. .

Further, the insulator 2 is on the outer periphery of the substantially rectangular cross section which is the winding surface 20 and has a large number of guide grooves 24 formed on both side portions sandwiching each corner portion. Each guide groove 24 is a part for guiding the coil 3 in the winding direction, and is formed in a semicircular arc shape that is easy to receive and position the coil 3 in the radial direction as can be seen from the enlarged view shown in FIG. Has been. In addition, in this insulator 2, a guide groove 25 that is longer than the guide groove 24 is formed on the upper and lower surfaces and in the middle of the left and right sides (see FIG. 1A).

The coil 3 has a configuration in which a highly conductive material such as copper is provided with an insulating film with enamel or the like, and has a substantially round longitudinal section. However, the coil may be, for example, a rectangular wire with a rectangular cross section. In this case, the shape of the

guide grooves

24 and 25 is also changed to a shape that facilitates positioning of the flat wire.

(Molding Method) FIGS. 6 and 7 show an example of a molding die used when the insulator 2 is formed on the outer peripheral portion of the above-described split core 1 by insert molding. In this example, the upper die 4, the lower die 5, the long slide dies 6 and 7 arranged opposite to each other, and the short slide dies 8 and 9 arranged in a direction crossing the slide dies 6 and 7 are totaled. It consists of a mold. 6 shows a mold configuration corresponding to the cross section of FIG. 5A, and FIG. 7 is a cross-sectional view taken along line DD of FIG.

The split core 1 is positioned and fixed in a state of being sandwiched between corresponding parts of the upper mold 4 and the lower mold 5. Between the upper mold 4 and the lower mold 5, the slide molds 6 and 7 are arranged to face each other and mainly form the left and right side surfaces of the insulator 2, and the front and rear end faces of the insulator 2 are mainly arranged to face each other. The

slide molds

8 and 9 are provided. The slide molds 6 to 9 are PL, which is a contact portion between the slide mold 6 and the slide mold 8, PL, which is a contact portion between the slide mold 6 and the slide mold 9, and a contact portion between the slide mold 7 and the slide 8. A certain PL, that is, a contact portion between the slide mold 7 and the slide mold 9, is set corresponding to the four corners of the insulator 2.

Between the slide molds 6 to 9 and the split core 1, there is provided a clearance that enables the winding surface 20 that is the outer periphery of the rectangle to be formed. Further, a clearance is provided between the slide molds 6 to 9 and the inner mold surfaces of the upper mold 4 and the yoke section 11 so that the rear flange section 21 can be formed. Similarly, a clearance that allows the front flange portion 22 to be formed is provided between the slide dies 6 to 9 and the lower die 4 and the tip surface of the tooth portion 10.

Further, each of the slide dies 6 to 9 is located at a place where the PL is formed as shown in FIG. 7, and is directed to a space that forms four corners of the clearance that enables the winding surface 20 to be formed. A protrusion-shaped portion that protrudes to form a recess 23, a protrusion-shaped portion (not shown) that is provided adjacent to each protrusion-shaped portion for forming the recess 23 and forms a guide groove 24, and a slide die 6, 7 is formed on the opposing inner surfaces of the projecting shape portion (not shown) that forms the guide groove 25, the four corner portions 21 a of the upper flange portion 21, and the four corner portions 22 a of the lower flange portion 22. It has a projection-shaped part (not shown) that enables the

hollow part

28 or 29 to be formed.

Therefore, in the insert molding, the insulating molten resin is filled from the gate (not shown) into the clearance, that is, the cavity with the molten resin filled at the set inflow speed and pressure, cured, and then released to integrate the insulator 2. In this way, the divided core 1 is obtained.

(Advantage) The split core 1 described above is formed as a motor stator by winding the coil 3 around the outer circumferential winding surface 20 a predetermined number of times. The coil winding operation is automatically performed by a coil winding apparatus as in the conventional case. In this operation, even if burrs are generated in the insert molding for forming the insulator 2, a portion including PL, which is a burr generation portion, is lowered by one step from the coil winding surface 20, that is, a step portion or a recess portion. Since the burr edge is formed away from the coil winding surface 20, the coil can be wound stably and accurately without being affected by the occurrence of burr during molding.

Moreover, in this structure, since the insulator 2 forms the hollow part 23 in the rectangular corner | angular part in the coil winding surface 20 outer periphery of a substantially rectangular cross section, as guessed from FIG.6 and FIG.7, it is a metal mold. The slide molds 6 to 9 in the mold can be simplified. In addition, in this structure, the coil 3 is wound so as to be accommodated in a partition portion between the winding surface 20 and the front and

rear flange portions

22 and 21. At that time, the

dents

28 and 29 on the inner peripheral surface of the flange portion together with the dent portion 23 on the inner surface of the flange portion, even if burrs are generated on the inner peripheral surface of the flange portion by insert molding, are lowered by one step. The

recesses

28 and 29 absorb the coil 3 so that it does not contact the burr edge and can be wound with high accuracy.

In addition, in this structure, the insulator 2 is formed in the outer peripheral portion sandwiching the rectangular corners, and guide grooves 24 that guide the coil 3 in the winding direction, and further guide grooves 25 provided between the corners. Therefore, the coil 3 is excellent in that it can reliably prevent the coil from slipping in the winding operation.

The motor stator of the present invention only needs to have the configuration specified in the claims, and details can be changed or developed with reference to the above description. As an example, the split core has a configuration in which the teeth portion and the yoke portion are integrally formed. However, as in Patent Document 1, it may be of a type that is retrofitted to an annular yoke core.

1 .... split core 2 ... insulator 3 ... coil 4 ... upper mold 5 ... lower mold 6 ... slide mold 7 ... slide mold 8 ... ·························································································································
22 ... Front flange (22a is a corner)
23 ... depression 24 ... guide groove 25 ... guide groove 28 ... depression 29 ... depression PL ... partitioning line Japan filed on March 15, 2017 The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2017-049265 are hereby incorporated herein by reference as the disclosure of the specification of the present invention.

Claims

A stator core for dividing a stator core, and a stator for a motor in which a coil is wound around an outer peripheral portion of the split core via a resin insulator, and the insulator is formed by insert molding on an outer peripheral portion of the split core. And a burr escape recess provided at a location including the parting line at the time of insert molding.
2. The motor according to claim 1, wherein the insulator has a winding surface on which the coil is wound is an outer periphery having a substantially rectangular cross section, and the depressions are located at corners of the polygon. Stator.
The insulator has a winding surface around which the coil is wound and a flange portion that rises from the front and rear ends of the winding surface, and the hollow portion is provided on a part of the inner peripheral surface of the flange portion together with the winding surface. The motor stator according to claim 2, wherein the motor stator is provided.
4. The motor stator according to claim 3, wherein the recess provided in the flange is located at a corner of the flange.
The insulator has a guide groove on the outer periphery of the substantially rectangular cross-section that is the winding surface, and is formed in an outer peripheral portion sandwiching the polygonal corner portion to guide the coil in the winding direction. The stator for motors according to any one of claims 2 to 4 characterized by these.