JP2023165352A - stator - Google Patents

Abstract

To provide a stator which has a further improved space factor of a coil.SOLUTION: A stator 1 comprises: a stator core 10 which has a yoke 11 and a plurality of teeth 12 radially protruding from the yoke 11; a coil 20 which is disposed in a slot 13 between the adjacent teeth 12, 12; and a fixing member 30 which fixes the coil 20 to the stator core 10. The stator core 10 has: an umbrella part 14 which circumferentially extends from a radial end of each of the teeth 12; and a cut-out part 141 which is formed by radially cutting out a portion on the slot 13 side of a circumferential end of the umbrella part 14. On its surface, the fixing member 30 has a foaming adhesive layer 32, and the fixing member is disposed between the adjacent cut-out parts 141, 141.SELECTED DRAWING: Figure 1

Description

The present invention relates to a stator.

Patent Document 1 describes fixing a coil and a core using insulating paper having a sheet-like base material and resin layers made of foamed resin provided on both sides of the base material.

JP2019-022276A

However, Patent Document 1 requires a space occupied by the foamed resin within the slot. Therefore, the space factor, which is the ratio of the cross-sectional area of the coil to the cross-sectional area of the slot, decreases accordingly. When the space factor of the coil decreases, there is a problem in that the torque characteristics and loss characteristics of the motor deteriorate.

The present invention was made to solve such problems, and an object of the present invention is to provide a stator in which the coil space factor is further improved.

A stator according to a first aspect of the present invention includes a stator core including a yoke and a plurality of teeth protruding from the yoke in a radial direction, a coil disposed in a slot between the adjacent teeth, and a coil disposed in a slot between the teeth. a fixing member for fixing to the stator core, the stator core includes an umbrella part extending in the circumferential direction from the radial end of the teeth, and a part of the circumferential end of the umbrella part on the slot side. and a notch portion cut out in the radial direction, and the fixing member has a foam adhesive layer on its surface and is disposed between the adjacent notch portions.

According to the welding device according to the first aspect of the present invention, the fixing member having the foam adhesive is arranged not in the slot but between adjacent notches, so that the space occupied by the foam resin in the slot is reduced. No longer needed. Thereby, it is possible to avoid a reduction in the space factor of the coil due to the foamed resin. Therefore, it is possible to provide a stator in which the space factor of the coils is further improved.

FIG. 1 is a perspective view showing an example of a stator according to Embodiment 1 of the present invention. 1 is a cross-sectional view showing an example of a stator core according to Embodiment 1 of the present invention. FIG. 2 is a partially enlarged view showing a cross section of a structure for fixing a coil and a stator core in Embodiment 1 of the present invention. FIG. 7 is a partially enlarged view showing a cross section of a structure for fixing a coil and a stator core in a comparative example.

Embodiment 1
Embodiment 1 of the present invention will be described below with reference to the drawings. However, the present invention is not limited to the first embodiment below. Further, in order to clarify the explanation, the following description and drawings are simplified as appropriate.

FIG. 1 is a perspective view showing an example of a stator 1 according to the first embodiment. Further, FIG. 2 is a cross-sectional view showing an example of the stator core 10. FIG. 2 shows a cross section of the stator core 10 cut along a plane perpendicular to the axial direction (Z-axis direction) of the stator 1. The stator 1 is a stator used in a rotating electric machine. A rotating electric machine in which the stator 1 is used includes the stator 1 shown in FIG. 1 and a rotor (not shown) disposed on the inner circumferential side of the stator 1 at a predetermined interval. Note that the rotating electric machine in which the stator 1 is used may include a rotor (not shown) disposed on the outer circumferential side of the stator 1 at a predetermined interval. As shown in FIGS. 1 and 2, the stator 1 includes a stator core 10, a plurality of segment coils 20, and a fixing member 30 (described later) that fixes the segment coils 20 to the stator core 10.

The stator core 10 is made up of annular magnetic thin plates laminated in the axial direction of the stator 1 (Z-axis direction in FIG. 1), and has a generally cylindrical shape as a whole. In FIG. 2, the radial direction and the circumferential direction are shown. The axial direction is a direction along the central axis of the center hole of the stator core 10. The radial direction is a radial direction passing through the central axis in a plane perpendicular to the axial direction, and the circumferential direction is a direction along the circumference around the central axis.

The stator core 10 includes a yoke 11, teeth 12, and slots 13. A plurality of teeth 12 are formed radially protruding from a plurality of positions on the inner peripheral surface of the annular yoke 11 at predetermined intervals. A slot 13 is formed in the space between adjacent teeth 12, 12.

The slot 13 has an opening shape extending in the radial direction of the stator core 10 as a longitudinal direction. Furthermore, the slots 13 are open toward the inner circumferential surface of the stator core 10. Here, an example is shown in which the circumferential width of the slot 13 is constant across the radial direction. Note that the width of the slot 13 may be formed to widen as it goes radially outward, or conversely, it may be formed as it narrows as it goes radially outward.

Each slot 13 of the stator core 10 is wound with three-phase (U-phase, V-phase, W-phase) coils. The number of slots 13 formed in the stator core 10 corresponds to the number of magnetic poles of the rotor. A plurality of segment coils 20 are arranged in the longitudinal direction of the slot 13. The segment coil 20 is formed using a plurality of substantially U-shaped conductor segments. The conductor segment is, for example, a rectangular conductor with a rectangular cross section formed into a substantially U-shape.

Although not shown here, the conductor segment has two lead parts that are parallel to each other and an anti-lead part that connects them. The surface of the conductor segment except the tip of the lead portion is coated with insulation. The tip of the lead portion protrudes from one end surface in the axial direction (the upper end surface in FIG. 1) of the stator core 10 shown in FIG. Further, the anti-lead portion is located on the other end surface (lower end surface in FIG. 1) of the stator core 10 in the axial direction.

A plurality of conductor segments are inserted into two circumferentially spaced slots 13 in a state in which they are lined up in the radial direction of the stator core 10. A portion of the conductor segment that protrudes from one end surface of the stator core 10 in the axial direction is bent so as to be inclined with respect to the axial direction of the stator core 10. After bending the lead portions of the conductor segments, the tips of the lead portions of radially adjacent conductor segments are welded and connected to each other, thereby winding the segment coil 20 around the teeth 12 of the stator core 10.

Next, a structure for fixing segment coil 20 and stator core 10 in Embodiment 1 of the present invention will be described with reference to FIG. 3. FIG. 3 shows a cross section of the radial ends of the adjacent teeth 12, 12, the segment coil 20 disposed in the slot 13 between the adjacent teeth 12, 12, the umbrella portion 14, and the fixing member 30. FIG. The umbrella portion 14 is also referred to as a flange portion. FIG. 3 shows a cross section of the stator 1 taken along a plane perpendicular to the axial direction (Z-axis direction) of the stator 1.

As shown in FIG. 3, the stator core 10 further includes an umbrella section 14. The umbrella portion 14 extends in the circumferential direction from the radial end portion of the teeth 12. Further, the umbrella portion 14 has a cutout portion 141 in which a portion of the circumferential end of the umbrella portion 14 on the slot 13 side is cut out in the radial direction. Thereby, a space is formed outside the radial end of the slot 13 between the adjacent teeth 12, 12 and between the adjacent notches 141, 141 to accommodate the fixing member 30.

The fixing member 30 includes a base material 31 and a foam adhesive layer 32 formed on the surface of the base material 31. Further, the fixing member 30 is arranged between the adjacent notches 141, 141. Then, the foam adhesive layer 32 of the fixing member 30 comes into contact with the surface of the segment coil 20 disposed at the radial end of the slot 13, and the surface of the cutout portions 141, 141 (a part of the surface of the umbrella portion 14). The segment coils 20 and the stator core 10 are fixed by contacting the segment coils 20 and the stator core 10.

As the base material 31, a resin material having heat resistance and insulation properties molded into a sheet shape can be used. As the resin material, polyphenylene sulfide (PPS), polyethylene naphthalate (PEN), epoxy resin, etc. are used. Further, the base material 31 may be an insulating sheet 40 described later.

The foam adhesive layer 32 is made of a thermosetting resin that expands and hardens when heated, and has adhesive properties itself. The foamed adhesive layer 32 expands due to heating, and thus becomes, for example, several times thicker than its initial state. As the resin material, an epoxy foam resin material can be used.

Further, an insulating sheet 40 is arranged between the inner peripheral surface of the slot 13 and the segment coil 20. The insulating sheet 40 is a sheet-shaped insulating member for electrically insulating the stator core 10 and the segment coils 20.

As the insulating sheet 40, similarly to the base material 31, a sheet formed from a resin material having heat resistance and insulating properties can be used.

Although not shown here, the insulating sheet 40 is arranged so as to surround the four sides of the plurality of segment coils 20 arranged in a row in the radial direction of the slot 13. Further, a part of the insulating sheet 40 covering the segment coil 20 disposed at the radial end of the slot 13 is sandwiched between the segment coil 20 and the surface of the umbrella portion 14 on the slot 13 side. be. Note that the insulating sheet 40 extends to the space between the adjacent notches 141, 141, and the foam adhesive layer 32 is formed in the portion extending between the notches 141, 141 of the insulating sheet 40. The fixing member 30 may be formed by. That is, the base material 31 of the fixing member 30 may be a portion extending between the notches 141, 141 of the insulating sheet 40. In other words, the fixing member 30 connects the base material 31, which is a portion extending between the notches 141, 141 of the insulating sheet 40, and the foam adhesive layer 32 formed on both surfaces of the base material 31. You may prepare.

Further, both ends of the insulating sheet 40 in the axial direction (Z-axis direction in FIG. 1) are provided to protrude outward from both end surfaces of the stator core 10 in the axial direction (Z-axis direction in FIG. 1), respectively.

Next, the problems of the comparative example will be explained with reference to FIG. Among the configurations of the stator according to the comparative example, the same components as those of the stator 1 according to the first embodiment are given the same reference numerals. In the comparative example, the umbrella portion 14 does not have the cutout portion 141. In addition, in the comparative example, the foam adhesive layer 41 is formed over substantially the entirety of both surfaces of the insulating sheet 40, and the foam adhesive layer 41 of the insulating sheet 40 is formed on the inner peripheral surface of the slot 13 and the segment coil. Segment coil 20 and stator core 10 are fixed by contacting the surface of segment coil 20 . The comparative example requires a space occupied by the foam adhesive layer 41 inside the slot 13. Therefore, the space factor, which is the ratio of the cross-sectional area of the coil to the cross-sectional area of the slot, decreases accordingly. When the space factor of the coil decreases, there is a problem in that the torque characteristics and loss characteristics of the motor deteriorate.

On the other hand, according to the stator 1 according to the first embodiment, the fixing member 30 having the foam adhesive layer 32 is disposed not within the slot 13 but between the adjacent notches 141, 141. The space occupied by the foamed resin within the slot 13 becomes unnecessary. Thereby, it is possible to avoid a decrease in the space factor of the segment coil 20 due to the foamed resin. Therefore, it is possible to provide the stator 1 in which the space factor of the coils is further improved.

Note that the present invention is not limited to the above embodiments, and can be modified as appropriate without departing from the spirit.

1 Stator 10 Stator core 11 Yoke 12 Teeth 13 Slot 14 Umbrella portion 141 Notch portion 20 Segment coil 30 Fixing member 31 Base material 32 Foam adhesive layer 40 Insulating sheet

Claims (1)

a stator core including a yoke and a plurality of teeth protruding from the yoke in a radial direction;
a coil disposed in a slot between the adjacent teeth;
a fixing member that fixes the coil to the stator core;
Equipped with
The stator core is
an umbrella portion extending in the circumferential direction from the radial end portion of the teeth;
a notch portion in which a part of the circumferential end of the umbrella portion on the slot side is cut out in the radial direction;
Equipped with
The fixing member has a foam adhesive layer on its surface and is disposed between the adjacent notches.
stator.

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