JP2008099376A - Stator, stator manufacturing method, and rotating electric machine - Google Patents

Abstract

【Task】
This makes it easy to form the segment coils, reduces molding errors, and facilitates the joining of the segment coils.
[Solution]
A folded portion that is curved in a substantially U shape in the segment coil, a first straight portion that extends substantially linearly from one end of the folded portion, and a first portion that extends away from the first straight portion from the other end of the folded portion. A first separating portion, a second bending portion that is curved so as to be substantially in the same direction as the first straight portion at the end of the first separating portion, and substantially in the same direction as the first straight portion from the second bending portion. A second linear portion extending linearly, a third curved portion curved in a direction away from the second linear portion with respect to the first linear portion, and a direction away from the third curved portion with respect to the first linear portion. The extended 2nd spaced-apart part is shape | molded and the edge parts of each segment coil are joined.
[Selection] Figure 6

Description

  The present invention relates to a rotating electrical machine, a stator used therefor, and a manufacturing method thereof, and more particularly, to a stator used in a motor, a generator, and the like.

  A stator in a conventional rotating electric machine is configured by winding a stator coil around a plurality of slots provided so as to open inward in the circumferential direction of the stator core. However, the stator coil is not damaged in the plurality of slots. There was a problem that it was difficult to wrap it around, and workability was poor.

  Therefore, as shown in Patent Document 1, the stator coil is configured by a plurality of U-shaped segment coils, and each segment coil is inserted into the slot from the axial direction of the stator core, and It has been considered that a stator coil is formed by twisting both ends in different directions and joining the ends of separate segment coils together by welding.

JP-A-11-155270

  However, the segment coil described in Patent Document 1 is formed into a U-shape before being inserted into the slot. In practice, however, the segment coil is formed in a direction in which each of the segments is separated from the U-shaped apex obtained by folding the wire rod. The wire rods on both sides are formed along the slot. Further, after inserting the segment coil into the slot, both ends of the segment coil are twisted in different directions. That is, each segment coil is curved at a plurality of positions from the U-shaped apex to both end sides. For this reason, the positions of both ends of the segment coil are shifted due to a molding error or the like, and it is necessary to adjust the position again in the welding process.

  An object of the present invention is to provide a stator, a stator manufacturing method, and a rotating electrical machine that can easily form segment coils, reduce molding errors, and facilitate joining of segment coils.

  The stator coil of the present invention includes a plurality of segment coils. The segment coil includes a folded portion that is curved in a substantially U shape, and a first straight portion that extends substantially linearly from one end of the folded portion. And a first separating portion extending in a direction away from the other end of the folded portion with respect to the first straight portion, and a curve so as to be in substantially the same direction as the first straight portion at the end of the first separating portion. A second curved portion, a second straight portion extending substantially linearly from the second curved portion in the same direction as the first straight portion, and a direction away from the second straight portion with respect to the first straight portion. Each of the segment coils includes a third bending portion that is curved in a direction and a second separation portion that extends in a direction away from the first bending portion from the third bending portion. The first straight portion in a state of being installed in the slot A tip, and the second separated portion of the other segment coil is characterized in that it is joined.

  The stator of the present invention includes a folded portion bent in a substantially U shape in the segment coil, a first straight portion extending substantially linearly from one end of the folded portion, and the first end from the other end of the folded portion. A first spacing portion extending in a direction away from the straight portion, a second bending portion curved at substantially the same direction as the first straight portion at the end of the first spacing portion, and the second bending portion A first forming step of forming a second linear portion extending substantially linearly in the same direction as the first linear portion by bending, and forming each of the formed segment coils into the respective slots of the stator core. A third step of bending the distal end side of the second linear portion of each of the segment coils mounted in the slot in a direction away from the first linear portion, and forming a third curved portion; The third bending portion A second forming step for forming the second spacing portion toward the tip, and a joining step for joining the tip of the first straight portion in each of the segment coils and the second spacing portion in the other segment coils It is characterized by being manufactured by.

  Moreover, the rotating electrical machine of the present invention has a rotor and a stator, and the stator coil wound around the stator is composed of a plurality of segment coils, and the segment coils are substantially U-shaped. A curved folded portion, a first linear portion extending substantially linearly from one end of the folded portion, a first spacing portion extending in a direction away from the first linear portion from the other end of the folded portion, A second curved portion that is curved so as to be substantially in the same direction as the first straight portion at the end of the first separation portion, and extends substantially linearly in the same direction as the first straight portion from the second curved portion. A second straight portion, a third curved portion that is curved away from the second straight portion with respect to the first straight portion, and a second extending from the third curved portion in a direction away from the first straight portion. Each of the segment coils is fixed. And the tip of the first straight portion in a state of being mounted on the core of each of the slots, and the second separated portion of the other segment coil is characterized in that it is joined.

  In the present invention, since the one end side from the folded portion of the segment coil is made substantially linear, the portion to be bent can be suppressed to the minimum, the segment coil can be easily molded, the molding error is reduced, and the segment coils Can be easily joined.

  As an embodiment of the rotating electrical machine of the present invention, an electric motor used for an electric four-wheel drive vehicle in which a wheel not driven by an engine is driven by an electric motor will be described as an example. FIG. 1 is a side sectional view of a driving electric motor used in an electric four-wheel drive vehicle.

  As an electric motor for driving an electric four-wheel drive vehicle, a winding field type synchronous motor is used. The electric motor includes a rotor 2 that is rotatably provided and a stator 3 that is fixedly disposed on the outer periphery of the rotor 2. The rotor 2 and the stator 3 are accommodated in a housing 4. ing.

  A shaft 1 for outputting a driving force is inserted into a housing 4 having an accommodating space inside in a state in which both end sides are rotatably supported by ball bearings 5a and 5b as bearings. Between these ball bearings 5a and 5b, two pairs of Rundel-type rotors 2a and 2b constituting the rotor 2 are fixed to the shaft 1 so as to be able to rotate integrally with the shaft 1 in a state of being adjacent to each other. Yes. Each of the Rundel-type rotors 2a and 2b includes a rotor core 2-1 having a plurality of claw magnetic poles extending in a taper shape in the axial direction, and a field coil that is wound around the shaft 1 inside the claw magnetic poles and around the shaft 1 2-2. This field coil 2-2 is wound around a resin bobbin in order to insulate it from the rotor core 2-1, and the slip ring 6 is always attached to the slip ring 6 via the slip ring 6 provided at the end of the shaft 1. The field current is supplied from the pressed brush 7. By supplying current to the field coil 2-2 in this way, different poles are formed alternately on each claw magnetic pole. That is, the rotor 2 is formed with a plurality of magnetic poles so that different poles are alternately arranged in the circumferential direction.

  Next, the stator 3 will be described based on FIGS. 2 to 8 in addition to FIG. FIG. 2 is a perspective view of one of the segment coils before being inserted into the stator core. FIG. 3 is a top view of the segment coil as viewed from above. FIG. 4 is a front view of the segment coil as viewed from the front. FIG. 5 is a side view of a state in which the segment coil is inserted into the stator core. FIG. 6 is a perspective view of a part of the stator. FIG. 7 is an explanatory view showing a joined state of the stator coil. FIG. 8 is a front view of the stator.

  The stator 3 has a stator core 3-1 configured by laminating electromagnetic steel plates and welding and fixing those electromagnetic steel plates on the outer peripheral side. The stator core 3-1 is arranged on the inner peripheral side. It has a plurality of slots 8 that are open. As shown in FIG. 5, the slot 8 has a substantially U-shape when viewed from one end surface in the axial direction, and extends to the other end side in the axial direction while maintaining this shape. In this embodiment, the slot 8 has a substantially U-shape, so-called an open slot. However, like the slot shape in a general stator, only the inner peripheral end on the slot 8 side is narrowed. It may be. The stator 3 configured in this way is fixed in the housing 4.

  A stator coil 3-2 for three phases is periodically wound around the slot 8 of the stator iron core 3-1, and the stator coil 3-2 welds a plurality of segment coils 3a. It is composed by joining. As shown in FIG. 2, the segment coil 3a before being inserted into the stator core 3-1 is formed by bending a rectangular wire having a rectangular cross section, specifically, a rectangular wire having a rectangular cross section at a plurality of locations. An insulating coating is applied to the surface by applying varnish or the like.

  The segment coil 3a before being inserted into the stator core 3-1 includes a folded portion 3a-1 folded into a substantially U shape on the short side of a rectangular cross section, and one end of the folded portion 3a-1. A first linear portion 3a-2 extending linearly from the first curved portion, a fifth curved portion 3a-3 in which the other side of the folded portion 3a-1 is folded in the long side direction, and a first through the fifth curved portion 3a-3. A first separating portion 3a-4 extending away from the straight portion 3a-2 in the direction of arrow A in FIG. 2 and substantially the same as the first straight portion 3a-2 from the end of the first separating portion 3a-4. Second curved portion 3a-5 bent in the long side direction so as to be in the same direction, and a second linear portion extending from the second curved portion 3a-5 in a substantially straight line in the same direction as the first straight portion 3a-2. 3a-6. Note that the tip of the second straight portion 3a-6 is longer in the axial direction than the tip of the first straight portion 3a-2. Further, since the slots 8 of the stator core 3-1 are provided radially, the fifth bending portion 3a-3 is arranged so that the segment coil 3a can be easily inserted into the slot 8 as shown in FIG. The second bending portion 3a-5 is twisted in the direction of arrow B by being bent at a slight angle.

  The segment coil 3a formed in this way peels off the insulation coating at the tips of the first straight part 3a-2 and the second straight part 3a-6, and at the first straight part 3a-2 as shown in FIG. A substantially V-shaped concave portion 3a-7 is provided at the short side portion on the second straight portion 3a-6 side, and the concave portion 3a- is provided on the short side portion on the first straight portion 3a-2 side in the second straight portion 3a-6. 7, a substantially V-shaped convex portion 3 a-8 is formed. The concave portion 3a-7 and the convex portion 3a-8 constitute a positioning portion.

Thereafter, the insulating paper is inserted into the slot 8, and the plurality of segment coils 3a formed with the concave portions 3a-7 and the convex portions 3a-8 are arranged in the slot 8 of the stator core 3-1, as shown in FIG. Each segment coil 3a is inserted from the axial direction, but as shown in FIG. 6, the segment coil 3a is formed with a folded portion 3a-1 bent in a substantially U shape on the short side, so that the first straight portion Both ends are distributed to the inner and outer circumferences so that 3a-2 is located on the outer circumference side and the second linear portion 3a-6 is located on the inner circumference side.

  In this way, the plurality of segment coils 3a are all inserted into the slots 8, and as shown in FIG. 8, the second straight portions 3a-6 of all the segment coils 3a are further separated from the first straight portions 3a-2. The third curved portion 3a-9 is formed by bending the long side in the circumferential direction and extends in a direction away from the third curved portion 3a-9 with respect to the first linear portion 3a-2 as shown in FIG. The distal end of the second separating portion 3a-10 is further bent at the long side so as to be in the substantially same direction as the first straight portion 3a-2, thereby forming the fourth bending portion 3a-11.

  By forming the third bending portion 3a-9, the second spacing portion 3a-10, and the fourth bending portion 3a-11, as shown in FIG. 6, the tip of the first straight portion 3a-2 in the other segment coil 3a And the front end side of the 4th curved part 3a-11 opposes, and the substantially V-shaped recessed part 3a-7 and the substantially V-shaped convex part 3a-8 provided in each opposing surface fit. In this state, joining is performed by sandwiching resistance welding in the directions of arrows C and D in FIG. Therefore, as shown in FIG. 7, the segment coil 3a has a straight line on one side and a curved part formed at four locations on the other side with the folded portion 3a-1 as a boundary.

  Next, the function and effect of this embodiment will be described below.

  The present embodiment is a stator having a stator core having a plurality of slots in the circumferential direction and a stator coil wound in the slots, and the stator coil is constituted by a plurality of segment coils. The segment coil includes a folded portion that is curved in a substantially U shape, a first linear portion that extends substantially linearly from one end of the folded portion, and a first linear portion that extends from the other end of the folded portion. A first separating portion extending in a direction away from the second bending portion, a second bending portion curved at substantially the same direction as the first straight portion at an end of the first separating portion, and the second bending portion from the second bending portion. A second linear portion extending substantially linearly in the same direction as the one linear portion, a third curved portion curved in a direction away from the second linear portion with respect to the first linear portion, and the third curved portion It extends in a direction away from the first straight portion. Each of the segment coils includes a distal end of the first straight portion and the second separation portions of the other segment coils in a state of being installed in the slots of the stator core. Since the segment coils are joined, one side of the segment coil remains a straight line with the folded portion as a boundary, and the other side has four curved portions. For this reason, the bending part of a segment coil can be reduced as much as possible, and also the side to be welded only needs to bend only one side in the circumferential direction, thus facilitating molding. Further, since the forming error can be reduced by the amount of the curved portion, the concave portion and the convex portion can be easily fitted.

  In addition, since the present embodiment has a fourth curved portion that is curved so as to be substantially in the same direction as the first straight portion on the distal end side of the second spacing portion, The one linear portion and the distal end side of the fourth bending portion can be opposed to each other in a substantially parallel state. For this reason, the effect that it is easy to join is acquired.

  Further, in the present embodiment, since the fifth curved portion is provided at the boundary between the other end of the folded portion and the first separation portion, the fixing is particularly made to improve the space factor in the slot. When the cross-section of the child coil is rectangular, the bent portion and the fifth bending portion can be easily formed by making the rectangular curved sides different.

  Further, in the present embodiment, since a positioning portion capable of positioning each is provided at the tip of the first linear portion of the segment coil and the tip of the second separation portion, the tip of the first linear portion The tips of the two spaced-apart portions can be easily joined.

  Further, in this embodiment, the positioning portion is constituted by the tip of the first linear portion of the segment coil, the convex portion provided at one of the tip ends of the second spacing portion, and the concave portion provided at the other. , Can be positioned reliably. In particular, in this embodiment, since the concave portion and the convex portion are substantially V-shaped, even when there is a slight deviation, the deviation can be automatically corrected using the V-shaped taper portion when sandwiched during resistance welding. it can.

  Although the present embodiment has been described above, the present invention is not limited to the present embodiment. For example, in this embodiment, a motor used in an electric four-wheel drive vehicle has been described as an example of a rotating electric machine. However, the present invention can also be applied to a drive motor used in a hybrid vehicle, a stator such as a vehicle AC generator. it can.

  In this embodiment, the stator coil has a rectangular cross section. However, the stator coil may have a circular cross section. In this case, the segment coil can be formed and connected without forming the fourth bending portion and the fifth bending portion.

  In the present embodiment, the substantially V-shaped concave and convex portions are described as the positioning portions, but the positioning portion is not limited to the substantially V-shape, and may be an arc shape or a square shape.

It is side surface sectional drawing of the electric motor for a drive used for an electric four-wheel drive vehicle. One of the segment coils before inserting in a stator core is made into the perspective view. It is the top view which looked at the segment coil from the upper part. It is the front view which looked at the segment coil from the front. It is a side view of the state which inserted the segment coil in the stator core. A part of stator is made into the perspective view. It is explanatory drawing which shows the joining state of a stator coil. It is a front view of a stator.

Explanation of symbols

2 Rotor 3 Stator 3-1 Stator core 3-2 Stator coil 3a Segment coil 3a-1 Folded portion 3a-2 First straight portion 3a-3 Fifth curved portion 3a-4 First separation portion 3a-5 2 curved part 3a-6 2nd linear part 3a-7 Recessed part (positioning part)
3a-8 Convex part (positioning part)
3a-9 3rd bending portion 3a-10 2nd separation portion 3a-11 4th bending portion 8 slot

Claims (13)

A stator having a stator core having a plurality of slots in the circumferential direction and a stator coil wound in the slots,
The stator coil is composed of a plurality of segment coils,
The segment coil is separated from the first linear portion from the folded portion bent into a substantially U shape, a first straight portion extending substantially linearly from one end of the folded portion, and the other end of the folded portion. A first spacing portion extending in a direction, a second bending portion curved so as to be substantially in the same direction as the first straight portion at an end of the first spacing portion, and the first straight portion from the second bending portion A second linear portion extending substantially linearly in the same direction, a third curved portion curved in a direction away from the second linear portion with respect to the first linear portion, and the first curved portion from the first curved portion. A second spacing portion extending in a direction away from the straight portion,
In each of the segment coils, the tip of the first straight portion and the second spacing portion of the other segment coil are joined in a state in which the segment coils are mounted in the slots of the stator core. And stator.   2. The stator according to claim 1, further comprising a fourth curved portion that is curved so as to be substantially in the same direction as the first linear portion on a distal end side of the second separation portion.   The stator according to claim 1, wherein a fifth curved portion is provided at a boundary portion between the other end of the folded portion and the first separation portion.   The stator according to any one of claims 1 to 3, wherein the segment coil has a rectangular cross section.   The stator according to claim 4, wherein the bent portion and the fifth bending portion of the segment coil have different rectangular curved sides.   The stator according to claim 2, wherein a positioning portion capable of positioning each of the first straight portion and the second separation portion of the segment coil is provided.   The positioning portion includes a tip of the first linear portion of the segment coil, a convex portion provided at one of the tip ends of the second spacing portion, and a concave portion provided at the other. The stator according to claim 6.   The stator according to claim 7, wherein the convex portion and the concave portion are configured to fit in a V shape. A stator manufacturing method comprising a stator core having a plurality of slots in the circumferential direction and a stator coil wound in the slots,
The stator coil is composed of a plurality of segment coils,
The segment coil is folded in a substantially U shape, a first linear portion extending substantially linearly from one end of the folded portion, and a direction away from the other end of the folded portion with respect to the first linear portion. A first bendable portion extending in the direction of the first bendable portion, a second bendable portion that is curved so as to be in substantially the same direction as the first straight line portion at an end of the first distant portion, and the first straight portion from the second bendable portion. A first forming step of forming a second linear portion extending substantially linearly in substantially the same direction by bending;
A mounting step of mounting each of the molded segment coils in each of the slots of the stator core;
The distal end side of the second linear portion of each of the segment coils mounted in the slot is bent in a direction away from the first linear portion to form a third curved portion, and from the third curved portion to the distal end A second forming step of forming a second spacing portion toward the
A joining step of joining the tip of the first straight portion in each of the segment coils and the second spacing portion in the other segment coils;
A stator manufacturing method comprising the steps of:   10. The stator according to claim 9, wherein, in the second forming step, the fourth bending portion is formed by bending the tip end side of the second separation portion so as to be in substantially the same direction as the first linear portion. Manufacturing method.   11. The stator according to claim 9, wherein, in the first forming step, a fifth curved portion is formed at a boundary portion between the other end of the folded portion and the first separation portion. Method.   The method for manufacturing a stator according to claim 9, wherein the segment coil is a rectangular wire. A rotor provided with a plurality of magnetic poles so that different poles alternate in the circumferential direction;
A stator having a stator core having a plurality of slots in the circumferential direction, and a stator coil wound in the slots;
A rotating electric machine comprising:
The stator coil is composed of a plurality of segment coils,
The segment coil is separated from the first linear portion from the folded portion bent into a substantially U shape, a first straight portion extending substantially linearly from one end of the folded portion, and the other end of the folded portion. A first spacing portion extending in a direction, a second bending portion curved so as to be substantially in the same direction as the first straight portion at an end of the first spacing portion, and the first straight portion from the second bending portion A second linear portion extending substantially linearly in the same direction, a third curved portion curved in a direction away from the second linear portion with respect to the first linear portion, and the first curved portion from the first curved portion. A second spacing portion extending in a direction away from the straight portion,
In each of the segment coils, the tip of the first straight portion and the second spacing portion of the other segment coil are joined in a state in which the segment coils are mounted in the slots of the stator core. Rotating electric machine.

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