JP2017034790A - Method for fixing segment coil of stator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce variations in penetration depth of an adhesive material at each slot of a stator.SOLUTION: A method for fixing segment coils of a stator comprises the steps of: arranging thermal foaming members 50 on an inner surface of each slot 13 at predetermined depth from an end surface of a stator core 10; forming each segment coil 20 by winding a segment 21 around the stator core 10 so that the segment 21 passes through between the thermal forming members 50 arranged on the inner surface of the slot 13; heating and expanding the thermal forming members 50; dropping an adhesive material 60 which has fluidity between the segment coil 20 and the inner surface of the slot 13; and curing the adhesive material 60.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a stator segment coil fixing method, and more particularly to a stator segment coil fixing method in which an adhesive material is dropped onto a segment coil wound around a stator core.

  In a stator of a motor used in a vehicle or the like, by dropping an adhesive material such as a varnish between a segment coil wound around a stator core tooth and the inner surface of the slot, and curing the adhesive material in the slot, the segment coil Is fixed to the stator core (see, for example, Patent Document 1).

JP2013-121296A

  In Patent Document 1, when an adhesive material is dropped onto a segment coil wound around a tooth, the adhesive material penetrates into the slot through the segment coil. The penetration depth of the adhesive material varies depending on each slot. Depending on the slot, there are a slot with a deep penetration depth of the adhesive material and a slot with a shallow penetration depth of the adhesive material. That is, the penetration depth of the adhesive material may vary in each slot.

  In the portion where the penetration depth of the adhesive material is deep, when the adhesive material is cured, the adhesion area by the adhesive material between the segment coil and the slot is increased, and the adhesive strength between the two is increased. On the other hand, in the portion where the penetration depth of the adhesive material is shallow, when the adhesive material is cured, the adhesion area by the adhesive material between the segment coil and the slot becomes small, and the adhesive strength between the two becomes lower than the portion where the penetration of the adhesive material is deep. As described above, since the adhesive strength between the segment coil and the slot is high in the portion where the penetration depth of the adhesive material is high, the stator resonance frequency is high, and in the portion where the penetration depth of the adhesive material is shallow, the segment coil and the slot are It is known that the stator resonance frequency is low because the adhesive strength is low.

  For this reason, the penetration depth of the adhesive material and the stator resonance frequency have a relationship that the stator resonance frequency becomes higher as the penetration depth of the adhesive material becomes deeper. In the slots where the stator resonance frequency is high and the penetration depth of the adhesive material is shallow, the stator resonance frequency is low.

  As a result, the stator resonance frequency varies in the stator, and the vibration of the stator may increase. Further, when the stator is used for a rotating electrical machine, the noise of the rotating electrical machine may be increased as the stator vibration increases.

  Accordingly, an object of the present invention is to reduce the variation in the penetration depth of the adhesive material in each slot of the stator.

  According to the stator coil coil fixing method of the present invention, a segment is formed on the stator core so as to pass between the step of providing a thermal foam member at a predetermined depth from the end face of the stator core on the inner surface of the slot and the thermal foam member provided on the inner surface of the slot. Forming a segment coil, heating and expanding the thermally foamed member, dropping a fluid adhesive material between the segment coil and the slot inner surface, and curing the adhesive material Including the step of.

  According to the present invention, the variation in the penetration depth of the adhesive material in each slot of the stator is reduced, and the vibration of the stator can be reduced.

It is a perspective view which shows the example of whole structure of a stator. It is sectional drawing along the radial direction of a slot. It is the front view of the slot which looked at the stator core from the inside. It is a front view of the slot which shows the state which mounts insulating paper in a slot. It is an enlarged view in the slot explaining the width | variety, thickness, and application | coating position of a thermal foaming member. It is a front view of the slot which shows the state which inserted the segment in the slot. It is a slot front view which shows the state which dripped adhesive material between a segment coil and a slot inner surface.

  First, the whole structure of the stator 1 of the rotary electric machine used for a vehicle etc. is demonstrated. As shown in FIGS. 1 to 3, the stator 1 includes a stator core 10, a segment coil 20 formed on the stator core 10, and insulating paper 40 that insulates between the stator core 10 and the segment coil 20.

  The stator core 10 includes an annular yoke 11 that extends along the circumferential direction of the stator, and a plurality of teeth 12 that protrude inward in the radial direction of the stator from the inner circumferential surface of the yoke 11. The plurality of teeth 12 are arranged at equal intervals in the stator circumferential direction. Slots 13 are formed between teeth 12 adjacent in the stator circumferential direction, and a plurality of slots 13 are arranged at equal intervals in the stator circumferential direction. Each tooth 12 and each slot 13 extends along the stator axial direction.

  As shown in FIG. 3, a resin cuff 30 covering the end surface of the tooth 12 is attached to one end surface of the stator core 10 in the stator axial direction. Although not shown, a similar cuffer 30 is also attached to the other end surface of the stator core 10 in the stator axial direction.

  The segment coil 20 is composed of a plurality of rectangular copper wire segments 21 inserted into all the slots 13 in the circumferential direction of the stator core 10. The segment 21 is U-shaped and includes two straight legs 21a. As shown in FIG. 2, a plurality of legs 21 a are stacked in the slot 13 in the stator radial direction.

  When the leg 21 a of the segment 21 is inserted into the slot 13, the leg 21 a has a length protruding from the slot 13. The portion of the leg 21a protruding from the slot 13 is bent and joined to the leg 21a of the other segment 21 to constitute the coil end 20a. Further, a U-shaped portion (not shown) also constitutes the coil end 20a.

  The segment coil 20 is wound around the tooth 12 through the slot 13 via the insulating paper 40. The segment coil 20 and the stator core 10 in each slot 13 are electrically insulated by the insulating paper 40.

  The insulating paper 40 is formed by bending a resin sheet or film having electrical insulation. Note that another thin material such as a nonwoven fabric may be used as long as electrical insulation can be ensured and flexibility is easy to bend.

  As shown in FIG. 3, a thermal foaming member 50 that expands by heating is provided in the slot 13 at a predetermined depth from one end surface of the stator core 10 in the stator axial direction. In the embodiment, the thermal foam member 50 is fixed in advance to both surfaces of the insulating paper 40. The thermal foaming member 50 is an epoxy resin containing a foaming agent, and fills between the inner surface of the slot 13 and the outer surface of the leg 21 a by expanding in the slot 13.

  A portion surrounded by the inner surface of the slot 13, the legs 21 a and the thermal foaming member 50 is filled with a thermosetting adhesive material 60 such as varnish. The segment coil 20 is fixed to the stator core 10 by the adhesive material 60 being cured.

  Next, a method for fixing the segment coil 20 to the stator core 10 will be described in detail. As shown in FIG. 4, the strip-shaped thermal foaming member 50 is provided along the front and back surfaces of the insulating paper 40 at a predetermined distance L from the edge 40 a corresponding to one end surface of the stator core 10 on the yoke 11 side of the insulating paper 40. Apply.

  Here, the width W, thickness Tp, and application position of the thermal foam member 50 will be described. The thermal foaming member 50 is intended to regulate the penetration depth of the adhesive material 60, and is expanded by being heated in the subsequent process. For this reason, it is required to fill the space between the inner surface of the slot 13 and the outer surface of the leg 21a without any gap after expansion. In order to satisfy this requirement, the width W, thickness Tp, and application position of the thermal foam member 50 are set.

  FIG. 5 shows a state in which the legs 21 a of the segments 21 are inserted into the slots 13 in order to explain the width W, thickness Tp, and application position of the thermal foam member 50. First, the application position of the thermal foam member 50 will be described. As described above, the penetration depth of the adhesive material 60 and the stator resonance frequency are closely related. For this reason, in FIG. 5, in order to define the penetration depth of the adhesive material 60, the thermal foam member 50 is applied to a position at a predetermined distance L from one end surface side of the stator core 10. By adjusting the predetermined distance L, a desired stator resonance frequency can be obtained. In addition, although the heat | fever foaming member 50 was apply | coated to the insulating paper 40, the heat | fever foaming member 50 may be previously formed in a strip | belt-shaped sheet | seat, and you may adhere | attach on the insulating paper 40 as this heat | fever foaming sheet.

  In FIG. 5, when the distance between the inner surface of the slot 13 and the outer surface of the leg 21a of the segment 21 is X, and the thickness of the insulating paper 40 is Tz, the thickness Tp of the thermal foam member 50 so that X ≧ Tz + 2Tp. Set. Since the thermal foaming member 50 expands by heating, the distance X is set to be equal to or less than the distance X in consideration of the expansion. That is, the thickness Tp of the thermal foam member 50 is set so that the space between the inner surface of the slot 13 and the outer surface of the leg 21a of the segment 21 is substantially filled by the thermal foam member 50. Note that X = Tz + 2Tp may be used to sufficiently fill the space between the outer surfaces of the legs 21a of the segment 21.

  The width W of the band of the thermal foam member 50 is set to a width W that can stop the penetration of the adhesive material 60. That is, it is preferable to set the minimum width W necessary for restricting the penetration of the adhesive material 60.

  Next, as shown in FIG. 4, the insulating paper 40 coated with the thermal foaming member 50 is bent into a U-shape according to the shape of the slot 13 and inserted into the slot 13.

  In FIG. 6, the leg 21 a of the segment 21 is inserted between the thermal foam members 50 from the other end surface side of the slot 13 in the stator axial direction as indicated by an arrow F <b> 1 in the drawing. Since the leg 21a has a length protruding from the slot 13, the portion protruding from the slot 13 of the leg 21a is bent (see FIG. 7) and joined to the protruding portion of the other segment 21. The part joined to the other segment 21 and the U-shaped part constitute the coil end 20a. In this way, the segment coil 20 is formed.

  As shown in FIG. 7, after the segment coil 20 is formed, the stator core 10 is heated. By this heating, the thermally foaming member 50 is expanded and expanded. Due to the expansion of the thermal foam member 50, the space between the inner surface of the slot 13 and the outer surface of the leg 21a is filled without any gap. In other words, the space between the inner surface of the slot 13 and the leg 21a is partitioned into two spaces in the stator axial direction at a predetermined distance L from the end surface of the stator core 10.

  Thereafter, the adhesive material 60 is dropped from the adhesive material supply port 61 of the adhesive material supply device (not shown) to the coil end 20a of the segment coil 20. As shown by an arrow F2 in FIG. 7, the adhesive material 60 is transmitted from the coil end 20a to the leg 21a and permeates between the inner surface of the slot 13 and the leg 21a. When the adhesive material 60 reaches the thermal foaming member 50, the thermal foaming member 50 prevents further penetration of the adhesive material 60 and is surrounded by the inner surface of the slot 13, the outer surface of the legs 21a, and the thermal foaming member 50. The space is filled with the adhesive material 60.

  Then, the stator 1 is heated again, and the adhesive material 60 is cured. As the adhesive material 60 is cured, the leg 21 a of the segment coil 20 is fixed to the inner surface of the slot 13. As a result, the segment coil 20 is fixed to the stator core 10.

  In the above-described embodiment, the case where the thermal foaming member 50 is provided at a predetermined distance L from one end surface of the stator core 10 in the stator axial direction has been described. However, in addition to the thermal foaming member 50, the stator of the stator core 10 is provided. The thermal foaming member 50 may be provided at a position a predetermined distance L from the other end surface in the axial direction, and the adhesive material 60 may be dropped from the other end surface side. That is, even if the heat foaming members 50 are respectively provided at positions of a predetermined distance L from both end faces of the stator core 10 and the adhesive material 60 is supplied from both end face sides of the stator core 10, the segment coil 20 is fixed to the stator core 10. Good.

  As described above, the thermal foaming member 50 is provided in the slot 13 at a predetermined distance L from one end surface in the stator axial direction of the stator core 10, and the leg 21 a of the segment coil 20 is inserted into the slot 13. Since the thermal foaming member 50 is expanded by heating, the space between the inner surface of the slot 13 and the outer surface of the leg 21a of the segment coil 20 is filled without a gap.

  For this reason, when the adhesive material 60 is dropped onto the coil end 20a of the segment coil 20, the adhesive material 60 that permeates into the slot 13 is prevented from further permeation by the thermal foaming member 50. The penetration depth of the adhesive material 60 is the same. That is, the penetration depth is uniform in the stator axial direction of each slot 13, and variations in the penetration depth of the adhesive material 60 in each slot 13 of the stator 1 can be reduced.

  As a result, variations in the stator resonance frequency of each slot 13 are also reduced, and an increase in vibration of the stator 1 can be suppressed. Further, an increase in noise of the rotating electrical machine due to the vibration of the stator 1 can be suppressed.

  Further, the penetration depth of the adhesive material 60 can be set to a desired depth, and the stator resonance frequency of each slot 13 can be easily set and adjusted.

  1 Stator, 10 Stator Core, 11 Yoke, 12 Teeth, 13 Slot, 14 Cuff, 20 Segment Coil, 20a Coil End, 21 Segment, 21a Leg, 30 Cuff, 40 Insulating Paper, 40a Edge, 50 Thermal Foam Member, 60 Adhesive Material 61 Adhesive material supply port.

Claims (1)

Providing a thermal foam member at a predetermined depth from the end face of the stator core on the inner surface of the slot;
Winding a segment around a stator core so as to pass between thermal foaming members provided on the inner surface of the slot to form a segment coil;
Heating and expanding the thermally foamed member;
Dropping a flowable adhesive material between the segment coil and the slot inner surface;
Curing the adhesive material;
A stator coil fixing method including a stator.