JP2022174650A - stator - Google Patents

Abstract

To suppress the stress concentration of an insulating resin that covers a joint of a conductor segment that forms a stator coil.SOLUTION: A stator 100 includes a coil 30 including a connecting portion row 36a in which a plurality of connecting portions 36 in which one conductor segment 31 and another conductor segment 31 are welded are arranged in the radial direction, and an insulating resin 20 including a plurality of ridges 21 and grooves 22 extending radially so as to cover the outside of the connection portion row 36a. An outer peripheral portion 20a of the groove 22 is composed of first cylindrical surfaces 25L and 25R connected to both side surfaces 24L and 24R and having a smaller diameter than the width of the groove portion 22, and a first flat surface 26 connecting between them. An inner peripheral portion 20b in which the width of the groove portion 22 is smaller than the diameter of the first cylindrical surfaces 25L and 25R is composed of the first cylindrical surfaces 25L and 25R connected to the side surfaces 24L and 24R, and a second cylindrical surface 27 that contacts and connects the first cylindrical surfaces 25L and 25R.SELECTED DRAWING: Figure 7

Description

The present invention relates to the structure of a stator for a rotating electric machine, and more particularly to the shape of insulating resin covering coil ends of the stator.

In recent years, in a rotating electrical machine, a stator has a coil in which one end of one U-shaped conductor segment and the other end of another U-shaped conductor segment are welded and connected outside the axial end surface of the stator core. is used. In such a stator, the outer surfaces of the connection portions of the conductor segments are covered with an insulating resin to ensure insulation (see, for example, Patent Document 1).

JP 2012-115144 A

When the U-shaped conductor segments are welded to connect the coils as in the stator disclosed in Patent Document 1, the circumferential intervals of the connection portions of the conductor segments are wider on the outer peripheral side and narrower on the inner peripheral side. The circumferential interval of the outer surface of the insulating resin covering the outer surface of the portion is also wider on the outer peripheral side and narrower on the inner peripheral side. For this reason, there is room for improvement because stress concentration due to thermal expansion occurs in the insulating resin on the inner peripheral side where the interval between the outer surfaces of the insulating resin is narrow.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to suppress the stress concentration of the insulating resin covering the connecting portions of the conductor segments.

The stator of the present invention includes a stator core and a plurality of connecting portions in which one end of one conductor segment and the other end of another conductor segment are welded outside the axial end face of the stator core. A stator including: a coil including a plurality of rows of connecting portions; a plurality of ridges covering the outside of the rows of connecting portions and extending radially; and an insulating resin including grooves between the ridges. The outer peripheral portion of the groove portion is composed of a first cylindrical surface having a diameter smaller than the width of the groove portion and connected to both side surfaces and a first flat surface connecting the first cylindrical surfaces at the bottom, The inner peripheral portion where the width of the groove portion is smaller than the diameter of the first cylindrical surface includes the first cylindrical surfaces connected to both side surfaces and the first cylindrical surfaces contacting the first cylindrical surfaces at the bottom. a second cylindrical surface connecting between, or a third cylindrical surface connecting to both side surfaces and having a diameter equal to or less than the width of the groove and smaller than the diameter of the first cylindrical surface; and a second plane connecting between the third cylindrical surfaces at the bottom.

In the inner peripheral portion where the width of the groove is smaller than the diameter of the first cylindrical surface, if the first cylindrical surfaces are in contact with both side surfaces of the groove, the two first cylindrical surfaces intersect at the center of the bottom of the groove. Corners are formed and stress concentration occurs. In the present invention, the inner peripheral portion of the groove portion is composed of two first cylindrical surfaces and the second cylindrical surface that contacts and connects the first cylindrical surfaces to each other. The stress concentration can be suppressed by preventing the formation of the part.

In addition, in the present invention, both side surfaces of the groove are in contact with third cylindrical surfaces having a diameter smaller than that of the first cylindrical surface, and the two third cylindrical surfaces are connected by a second plane to form the bottom surface of the groove. Stress concentration can be suppressed by not forming corners in the center of the .

The present invention can suppress stress concentration in the insulating resin that coats the connecting portions of the conductor segments.

It is a perspective view showing the stator of the embodiment. FIG. 3 is a perspective view showing a stator before being coated with an insulating resin, in which coil ends are configured by welding the ends of conductor segments; FIG. 4 is a perspective view showing a stator core and conductor segments inserted into slots; FIG. 2 is a sectional view taken along the line AA shown in FIG. 1, showing a connecting portion of a conductor segment and an insulating resin; FIG. 4 is a plan view of a connecting portion between an insulating resin and a conductor segment; 6 is an enlarged cross-sectional view of the groove portion of the outer peripheral portion of the insulating resin, which is a cross-section taken along the line BB shown in FIG. 5. FIG. 6 is an enlarged cross-sectional view of the groove portion of the inner peripheral portion of the insulating resin, which is the CC cross-section shown in FIG. 5. FIG. 6 is an enlarged cross-sectional view of the groove portion of the inner peripheral portion of the insulating resin having another shape, which is a cross-section taken along line CC shown in FIG. 5. FIG. FIG. 10 is a plan view of a connecting portion of a comparative insulating resin and a conductor segment; 10 is an enlarged cross-sectional view of the groove portion of the inner peripheral portion of the insulating resin, which is a cross-section taken along the line DD shown in FIG. 9. FIG.

A stator 100 according to an embodiment will be described below with reference to the drawings. As shown in FIG. 1, the stator 100 according to the embodiment has the connecting portions 36 (see FIGS. 2, 4 and 5) of the conductor segments 31 on the lead side covered with an insulating resin 20. As shown in FIG. In the stator 100 shown in FIG. 1, the input/output terminals (not shown) of the coil 30 are attached to the coil end 37 side. , the side opposite to the coil end 37 is called the anti-lead side.

As shown in FIG. 2, stator 100 has coils 30 wound in slots 13 of stator core 10 .

As shown in FIG. 3, stator core 10 is configured by laminating a large number of electromagnetic steel sheets. The stator core 10 includes an annular yoke 11 extending along the circumferential direction of the stator 100 and a plurality of teeth 12 protruding radially inward of the stator 100 from the inner peripheral surface of the yoke 11 . A plurality of teeth 12 are arranged at regular intervals in the circumferential direction of stator 100 . Slots 13 are formed between teeth 12 adjacent in the circumferential direction of stator 100 . The plurality of slots 13 are arranged at regular intervals in the circumferential direction of the stator. Each tooth 12 and each slot 13 extend along the axial direction of the stator 100 .

The coil 30 is composed of a plurality of U-shaped conductor segments 31 . The conductor segment 31 has two straight leg portions 31a and a curved portion 31b connecting them. The outer surface of the conductor segment 31 is covered with an insulation except for the distal end portion 34 of the leg portion 31a which will be described later.

When the leg portion 31a of the conductor segment 31 is inserted into the slot 13 on the side opposite to the lead, the leg portion 31a protrudes outward from the axial end surface 11a of the stator core 10 on the lead side. The ends of the legs 31a are bent in the circumferential direction from the axial end face 11a of the stator core 10, and as shown in FIG. A distal end portion 34 is formed by bending from 33 in the axial direction and extending in the axial direction. 2, 4 and 5, the other end of the leg 31a of another conductor segment 31 is similarly bent to form a bent portion 32, an inclined portion 33 and a tip portion . The opposing surfaces of the two radially adjacent tip portions 34 are welded and joined by resistance welding or the like.

As a result, as shown in FIG. 2 , one end portion 34 forming the leg portion 31 a of one conductor segment 31 and the other end portion 34 forming the leg portion 31 a of the other conductor segment 31 are aligned with each other in the stator core 10 . The coils 30 are connected at the outer welded portions 35 of the axial end faces 11 a on the lead side, pass through the slots 13 , and are wound around the teeth 12 . As shown in FIGS. 2 and 5, the two ends 34 connected by the weld 35 are one end of the leg 31a of one conductor segment 31 and the other end of the leg 31a of the other conductor segment 31. A connecting portion 36 is configured to connect the ends of the .

As shown in FIG. 2, the bent portion 32, the inclined portion 33, and the tip portion 34 welded together form a lead-side coil end 37. As shown in FIG. 2 and 5, the lead-side coil end 37 includes a connecting portion group 36b in which a connecting portion row 36a in which a plurality of connecting portions 36 are arranged in a radial direction is arranged in a radial direction. A curved portion 31b of the conductor segment 31 protrudes axially outward from the axial end surface 11b of the stator core 10 on the opposite lead side. This curved portion 31b forms a coil end 38 on the side opposite to the lead.

As shown in FIGS. 4 and 5, the insulating resin 20 covering the coil end 37 on the lead side includes a plurality of ridges 21 extending radially covering the outside of the connection section row 36a and grooves between the ridges 21. 22 and an annular portion 23 covering a portion of the inclined portion 33 of the conductor segment 31 . A circumferential interval between the ridges 21 or a circumferential width W of the groove 22 is large on the outer peripheral side and gradually decreases toward the inner peripheral side.

As shown in FIG. 6, the groove portion 22 of the outer peripheral portion 20a of the insulating resin 20 includes both side surfaces 24L and 24R, first cylindrical surfaces 25L and 25R respectively connected to the both side surfaces 24L and 24R, and the first cylindrical surfaces 25L and 25R at the bottom. It consists of a first plane 26 connecting between the surfaces 25L and 25R. The first cylindrical surfaces 25L and 25R are cylindrical surfaces having a radius R1 and a central angle of approximately 90°. The diameter twice the radius R1 of the first cylindrical surfaces 25L and 25R=2×R1 is smaller than the width W1 of the groove 22, and the distance between the parting lines 25eL and 25eR on the bottom side of the first cylindrical surfaces 25L and 25R is They are connected by a first plane 26 having a width L1.

A comparative insulating resin 220 is shown in FIG. On the outer peripheral side, as with the groove 22 of the insulating resin 20 of the embodiment, the groove 222 has both side surfaces 224L and 224R, first cylindrical surfaces 225L and 225R connected to the both side surfaces 224L and 224R, respectively, and the first cylindrical surfaces 225L and 225R at the bottom. It consists of a first plane 226 connecting between the surfaces 225L and 225R. The width W of the groove portion 222 and the radius R1 of the first cylindrical surfaces 225L and 225R are the same as the width W of the groove portion 22 of the insulating resin 20 and the radius R1 of the first cylindrical surfaces 25L and 25R of the embodiment.

As shown in FIG. 9, the circumferential width W of the groove portion 222 of the insulating resin 220 is large on the outer peripheral side and gradually decreases toward the inner peripheral side. Therefore, the parting lines 225eL and 225eR on the bottom sides of the first cylindrical surfaces 225L and 225R approach each other toward the inner peripheral side, and the width between the parting lines 225eL and 225eR gradually narrows. 9, where the width W of the groove portion 222 is the same as the diameters of the first cylindrical surfaces 225L and 225R. When one cylindrical surface 225L, 225R is configured to touch, the parting lines 225eL, 225eR on the bottom side of the two first cylindrical surfaces 225R, 225L intersect, and as shown in FIG. A corner portion 229 is formed at the edge, resulting in stress concentration. Therefore, in the stator 100 of the embodiment, the width W of the groove portion 22 is smaller than the diameters of the first cylindrical surfaces 25L and 25R. It has a different configuration.

As shown in FIG. 7, the groove portion 22 of the inner peripheral portion 20b includes first cylindrical surfaces 125L and 125R connected to both side surfaces 24L and 24R, and a bottom portion contacting the first cylindrical surfaces 125L and 125R. and a second cylindrical surface 27 connecting between the cylindrical surfaces 125L and 125R. The second cylindrical surface 27 is a curved surface that connects the first cylindrical surfaces 125L and 125R by fillet joints, and tangential lines 25fL and 25fR are connecting lines between the second cylindrical surface 27 and the first cylindrical surfaces 125L and 125R. Here, the first cylindrical surfaces 125L and 125R are cylindrical surfaces having a radius R1 and a center angle smaller than 90°, like the first cylindrical surfaces 25L and 25R. For example, it is a cylindrical surface of about 60°. The second cylindrical surface 27 is a cylindrical surface with a radius R2 in contact with the first cylindrical surfaces 125L and 125R.

As shown in FIG. 5, at a point 91 in FIG. 5 where the width W of the groove portion 22 is the same as the diameter of the first cylindrical surfaces 25L and 25R, the width of the second cylindrical surface 27 is zero and the width of the second cylindrical surface 27 is zero. does not appear. At a position slightly inner peripheral from the point 91, the radius R2 of the second cylindrical surface 27 is larger than the radius R1 of the first cylindrical surfaces 25L and 25R, and the width of the second cylindrical surface 27 appears. After that, the width of the second cylindrical surface 27 increases toward the inner peripheral side. Also, the radius R2 of the second cylindrical surface 27 may be smaller than the first cylindrical surfaces 25L and 25R toward the inner peripheral side. Further, the height h from the reference height 92 of the annular portion 23 to the bottom portion of the second cylindrical surface 27 shown in FIG. It may be gradually shallower towards the side.

As described above, in the inner peripheral portion 220b where the width W of the groove portion 222 is smaller than the diameters of the first cylindrical surfaces 225L and 225R like the insulating resin 220 of the comparison, the both side surfaces 224L and 224R of the groove portion 222 are provided with When the first cylindrical surfaces 225L and 225R are configured to contact each other, the parting lines 225eL and 225eR on the bottom side of the two first cylindrical surfaces 225L and 225R intersect, and a corner portion 229 is formed at the center of the bottom of the intersecting groove portion 22. stress concentration occurs. On the other hand, in the insulating resin 20 of the stator 100 of the embodiment, the two first cylindrical surfaces 25L and 25R are located at the inner peripheral portion 20b where the width W of the groove portion 22 is smaller than the diameter of the first cylindrical surfaces 25L and 25R. By connecting the second cylindrical surface 27 so as to contact the first cylindrical surfaces 25L and 25R between .

Also, since the height h from the reference height 92 of the annular portion 23 to the bottom portion of the second cylindrical surface 27 shown in FIG. can be done.

Next, the structure of the groove portion 22 of the other inner peripheral portion 20b of the insulating resin 20 will be described with reference to FIG. As shown in FIG. 8, the groove portion 22 of the inner peripheral portion 20b has third cylindrical surfaces 28L and 28R connected to the side surfaces 24L and 24R and a second flat surface connecting the third cylindrical surfaces 28L and 28R at the bottom. 29. The diameter twice the radius R3 of the third cylindrical surfaces 28L and 28R=2×R3 is equal to or less than the width W2 of the groove 22 and smaller than the diameter of the first cylindrical surfaces 25L and 25R of the outer peripheral portion 20a=2×R1. ing. Also, the radius R3 becomes smaller toward the inner peripheral side.

In this way, it is composed of the third cylindrical surfaces 28L, 28R connecting the groove 22 of the inner peripheral portion 20b to the side surfaces 24L, 24R, and the second flat surface 29 connecting the third cylindrical surfaces 28L, 28R at the bottom. However, since the radius R3 is made smaller toward the inner peripheral side, the parting lines 28eR and 28eL on the bottom side of the two third cylindrical surfaces 28L and 28R intersect, and a corner portion 229 is formed at the center of the bottom of the intersecting groove portion 22. It is possible to suppress the occurrence of stress concentration due to formation. Here, the radius R3 of the third cylindrical surfaces 28L, 28R can be freely set, but for example, it is about 1/5 to 1/2 of the radius R1 of the first cylindrical surfaces 25L, 25R. good too. The diameter of twice the radius R3 of the third cylindrical surfaces 28L and 28R=2×R3 is made equal to the width W2 of the groove 22 so that the width of the second plane 29 is zero. good too.

Reference Signs List 10 stator core 11 yoke 11a, 11b axial end face 12 tooth 13 slot 20, 220 insulating resin 20a outer peripheral portion 20b, 220b inner peripheral portion 21 ridge portion 22, 222 groove portion 23 annular portion , 24L, 24R, 224L, 224R Side surface 25L, 25R, 125L, 125R, 225L, 225R First cylindrical surface 25eL, 25eR, 28eR, 28eL, 225eL, 225eR Parting line 25fL, 25fR Tangential line 26, 226 First plane, 27 second cylindrical surface, 28L, 28R third cylindrical surface, 29 second plane, 30 coil, 31 conductor segment, 31a leg portion, 31b bending portion, 32 bending portion, 33 inclined portion, 34 tip portion, 35 welding Part 36 Connection Part 36a Connection Part Row 36b Connection Part Group 37, 38 Coil End 100 Stator 229 Corner.

Claims (1)

a stator core;
A coil including a plurality of rows of connecting portions in which a plurality of connecting portions are radially aligned, wherein one end of one conductor segment and the other end of another conductor segment are welded outside the axial end face of the stator core. When,
A stator including: a plurality of ridges extending radially covering the outer side of the row of connection portions; and an insulating resin including grooves between the ridges,
The outer peripheral portion of the groove is composed of a first cylindrical surface having a diameter smaller than the width of the groove connected to both side surfaces and a first flat surface connecting the first cylindrical surfaces at the bottom,
The inner peripheral portion, in which the width of the groove portion is smaller than the diameter of the first cylindrical surface, includes the first cylindrical surfaces connected to both side surfaces and the first cylindrical surface that is in contact with the first cylindrical surface at the bottom. a second cylindrical surface connecting between the surfaces;
Alternatively, a third cylindrical surface connected to both side surfaces and having a diameter equal to or less than the width of the groove and smaller than the diameter of the first cylindrical surface, and a third cylindrical surface at the bottom. a second plane connecting between
A stator characterized by:

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