JP6945611B2 - Rotating machine stator - Google Patents

Description

The present application relates to a stator of a rotary electric machine.

In recent years, rotary electric machines such as motors and generators are required to be compact, have high output, and have high efficiency. In order to meet these demands, especially in an in-vehicle motor, distributed winding using a coil having a substantially rectangular cross section is adopted as a stator. A stator that employs distributed winding can improve the coil space factor compared to a centralized winding stator, has the effect of increasing output, and has a smooth distribution of the rotating magnetic field, resulting in noise. Has a small advantage. However, on the other hand, the distributed winding has a problem that the coil end portion is enlarged, the motor size is increased, and the layout property is deteriorated.

To solve such a problem, for example, Patent Document 1 discloses a stator of a rotary electric machine in which a bus bar connected to a coil is integrally molded with a resin to reduce an insulating space and suppress expansion of a coil end portion. .. Further, for example, Patent Document 2 discloses a stator of a rotary electric machine in which arc-shaped bus bars are installed in a staircase pattern in the stator axial direction of the outer peripheral portion of the stator to prevent expansion in the radial direction. The bus bar is a conductor for supplying electric power to the coil.

Japanese Unexamined Patent Publication No. 2012-143019 Japanese Unexamined Patent Publication No. 2012-249344

However, in the stator of the rotary electric machine disclosed in Patent Document 1, it is necessary to integrate the bus bar with a resin, which increases the manufacturing price, and the resin filling defect at the time of molding is directly linked to the insulation defect. There are also quality issues.
In the stator of a rotary electric machine disclosed in Patent Document 2, when a bus bar is connected on a staircase in the stator axial direction on the outer peripheral portion of the stator, space saving can be maintained in the radial direction, but expansion in the axial direction cannot be suppressed. There are challenges. Further, since the bus bar is arranged in a narrow space, there is a problem that the process is complicated and the manufacturing price is increased.

The present application discloses a technique for solving the above-mentioned problems, and an object of the present application is to provide a stator of a rotary electric machine capable of suppressing expansion of a coil end portion of a stator winding.

The stator of the rotary electric machine disclosed in the present application includes an annular or cylindrical stator core in which slots are arranged in the circumferential direction, a stator winding mounted on the stator core, and the stator winding. composed of a plurality of unit coils, and a bus bar connecting at least two pairs between the unit coils,
At least one set of the bus bar is arranged on each of the inner diameter side and the outer diameter side of the coil end portion of the unit coil, and has an arc portion formed in an arc shape. It is characterized in that the coil end portions are alternately arranged on the inner diameter side and the outer diameter side of the coil end portion .

According to the stator of the rotary electric machine disclosed in the present application, by allocating a plurality of bus bars to the inner and outer diameters, there is less overlap between the bus bars than when the bus bars are arranged on only one side, and it is necessary to secure an insulation distance. It is possible to suppress the expansion of the coil end portion of the stator winding.

It is a perspective view which shows the stator of the rotary electric machine according to Embodiment 1. FIG. It is a perspective view which shows the bus bar of the stator of the rotary electric machine according to Embodiment 1. FIG. It is a top view which shows a part of the stator of the rotary electric machine according to Embodiment 1. FIG. It is sectional drawing which shows a part of the stator of the rotary electric machine according to Embodiment 1. FIG.

Hereinafter, embodiments of a stator of a rotary electric machine according to the present application will be described with reference to the drawings. In each figure, the same or similar components are designated by the same reference numerals, and the sizes or scales of the corresponding components are independent of each other.

Embodiment 1.
FIG. 1 is a perspective view showing a stator of a rotary electric machine according to the first embodiment.
As shown in FIG. 1, the stator 100 has a stator core 1 having an annular or cylindrical shape and a stator winding 2 mounted on the stator core 1, and is included in the stator core 1. A plurality of magnetic poles 3 are arranged on the circumference in the circumferential direction. Slots 4 are formed between the magnetic poles 3, and ground insulating paper (not shown) is mounted in the slots 4. Further, a cylindrical case 5 made of a thin steel plate is arranged so as to surround the outer circumference of the stator core 1.

The stator winding 2 is composed of a plurality of unit coils, and each of the plurality of unit coils has a coil portion mounted in the slot 4 of the stator core 1 and a slot 4 protruding from the slot 4 and having a different circumferential direction. A coil end portion 6 between the coil portions mounted on the stator portion 6 and a terminal portion 6a projecting from the slot 4 in the axial direction and connecting to another unit coil of the stator winding 2 are provided. Further, the stator winding 2 has a bus bar 7 that electrically connects the terminal portions 6a of the plurality of unit coils, and the stator winding 2 is composed of the unit coil and the bus bar 7.

As shown in FIG. 2, the bus bar 7 is composed of a conductor having a rectangular cross section, for example, a copper wire, and one of the surfaces whose cross section is on the short side is a reference plane 7a perpendicular to the central axis of the stator core 1. The surface on the long side of the cross section is bent into an arc shape to form the arc portion 7b. Further, bent portions 7c are formed at both ends of the bus bar 7, and the bent portions 7c are bent twice for the reason described later. That is, in each of the bent portions 7c at both ends of the bus bar 7, the first bent portion 7d is first formed with the short side of the cross section of the bus bar 7 as a folded curved surface, and then the first bent portion 7d is bent. The second bent portion 7e is formed in the outward direction of the arc portion 7b with the long side side of the cross section of the portion 7d as a folded curved surface. In this way, both ends of the bus bar 7 are bent twice, that is, the first bent portion 7d and the second bent portion 7e, and the end portion of the second bent portion 7e, that is, the terminal portion of the bus bar 7. The cross section of 7f is configured so that it can be connected to the terminal portion 6a of the coil end portion 6 on the long side surface. Further, by performing a double bending process for forming the first bent portion 7d and the second bent portion 7e at both ends of the bus bar 7, a gap is formed below the arc portion 7b in FIG. 2. The gap serves as a relief to avoid coil interference. That is, the first bent portion 7d and the second bent portion 7e form a relief portion in which the arc portion 7b avoids coil interference.

Further, as shown in FIG. 3, the bus bar 7 has a first bus bar (hereinafter, referred to as an outer diameter side bus bar) 71 arranged on the outer diameter side of the coil end portion 6 in the circumferential direction, and an inner diameter side of the coil end portion 6. The second bus bar (hereinafter referred to as the inner diameter side bus bar) 72 arranged in the above is divided into inner and outer diameters. The outer diameter side bus bar 71 and the inner diameter side bus bar 72 are arranged alternately on the outer diameter side and the inner diameter side of the coil end portion 6 in the circumferential direction. The outer diameter side bus bar 71 and the inner diameter side bus bar 72 of the adjacent bus bars 7 are arranged so that both ends of the arc and a part of the respective angles θ1 and θ2 formed by the center P of the stator core 1 overlap. Has been done. As a result, the coil end portion 6 is suppressed from expanding.

Further, as shown in FIG. 3, the inner diameter side bus bar 72 has a structure arranged outside the inner diameter of the stator 100, and when combined with a rotor (not shown), from either side of the stator 100 in the axial direction. But the rotor can be inserted.

Further, each of both ends of the bus bar 7 is subjected to a double bending process in which a relief portion for avoiding coil interference is formed as described above, and a reference plane 7a perpendicular to the central axis of the stator 100 is formed. As shown in FIG. 4, all the bus bars 7 are arranged so as to coincide with the virtual reference plane L which is the reference plane in the process. The virtual reference plane is the axial height (axial position) after the coil is bent. By making this virtual reference plane the same for each bus bar 7, in other words, the outer diameter side bus bar. This is a reference plane set for the purpose of obtaining the following effects by positioning the 71 and the inner diameter side bus bar 72 in one place.
(1) Welding of terminals can be performed at the same position and the same distance only by rotating the stator 100, the number of welding devices or jigs is reduced, and the equipment price is reduced.
(2) When confirming the welding state after welding, for example, it can be performed by one image processing determination, and the confirmation time can be shortened.

As a result, in the processing process of the coil end portion 6, it is easy to integrate processes such as positioning and welding (connection), equipment or jigs can be simplified, and equipment cost can be significantly reduced. In terms of management, the structure is also advantageous in terms of production efficiency, such as being able to collectively identify all welded parts with a single image photograph.

As described above, in the stator 100 of the rotary electric machine according to the first embodiment, by allocating the plurality of bus bars 7 to the inner and outer diameters, the portion where the bus bars 7 overlap each other is reduced as compared with the case where the bus bars 7 are arranged only on one side. It suppresses the places where it is necessary to secure the insulation distance. As a result, the expansion of the coil end portion 6 can be suppressed. Further, it is possible to design with a high degree of layout freedom, such as locally arranging the bus bar 7 on the inner diameter side according to the shape of the storage portion of the stator 100.

Further, by alternately allocating the bus bars 7 to the inner and outer diameters, it is not necessary to secure the insulation distance between the bus bars 7 even if the bus bars 7 are partially overlapped in the circumferential direction, so that the coil end portion 6 is expanded. Can be suppressed as a whole. Further, the bus bar 7 can be lengthened in the circumferential direction, and the degree of freedom in coil arrangement is improved.

In addition, the virtual reference surfaces L of all the bus bars 7 arranged on the inner and outer diameter sides are arranged on the same surface, which makes it easy to integrate processes such as positioning and welding (connection), and simplifies equipment or jigs. Therefore, the equipment cost can be significantly reduced.

Further, the inner diameter side bus bar 72 arranged on the inner diameter side is set to fit on the outer diameter side of the inner diameter side of the stator 100, whereby the rotor can be moved from either side of the stator 100 in the axial direction in the assembly process. It can be inserted, and has the advantage of being able to flexibly respond even if the storage process of the rotary electric machine changes.

Further, the surface of the bus bar 7 has an insulating film except for the terminal portion 7f. By having an insulating film on the surface of the bus bar 7, the distance required for insulation with the coil end portion 6 can be reduced. That is, since the bus bar 7 and the coil end portion 6 can be arranged close to each other, the expansion of the coil end portion 6 can be suppressed.

Further, in the connection portion between the bus bar 7 and the coil end portion 6, the cross section of the bus bar 7 is configured to be connected to the coil end portion 6 on the long side surface, so that a large connection area can be easily secured and weldability is improved. It is excellent and has the advantage of reducing welding defects.

Further, in the bus bar 7, an arc portion 7b is formed by bending, and bent portions 7c are formed at both ends. In the bent portion 7c, the cross section of the bus bar 7 has a bent curved surface on the short side. One bent portion 7d is formed, the cross section of the first bent portion 7d that is bent has a bent curved surface on the long side side, and the second bent portion 7e is formed in the outward direction of the arc portion 7b. It has been processed. Therefore, in the bus bar 7, a relief portion for avoiding coil interference is formed by bending both ends twice, and the short side of the cross section is in the radial direction, and the cross section of the bus bar 7 is a surface on the long side. Can be connected with, and the overhang of the bus bar 7 toward the inner diameter side can be suppressed. At this time, by simultaneously processing the arc portion 7b of the bus bar 7 and the bending processing of the bent portions 7c formed at both ends in the axial direction, the manufacturing cost can be suppressed and the processing can be easily performed.

Although exemplary embodiments are described in the present application, the various features, aspects, and functions described in the embodiments are not limited to the application of a particular embodiment, either alone or. It can be applied to embodiments in various combinations.
Therefore, innumerable variations not illustrated are envisioned within the scope of the techniques disclosed in the present application. For example, it is assumed that at least one component is modified, added or omitted.

1 Stator core, 2 Stator winding, 3 magnetic poles, 4 slots, 5 cases, 6 coil ends, 6a terminals, 7 busbars, 7a reference planes, 7b arcs, 7c bends, 7d first bends Part, 7e 2nd bent part, 7f terminal part, 71 outer diameter side bus bar (1st bus bar), 72 inner diameter side bus bar (2nd bus bar), 100 stator, L virtual reference plane, P center, θ1, θ2 angle

Claims (7)

An annular or cylindrical stator core with slots arranged in the circumferential direction,
With the stator winding attached to the above stator core ,
Constitute the stator winding in a plurality of unit coils, and a bus bar connecting at least two pairs between the unit coils,
At least one set of the bus bar is arranged on each of the inner diameter side and the outer diameter side of the coil end portion of the unit coil, and has an arc portion formed in an arc shape. A stator of a rotating electric machine, characterized in that it is alternately arranged on the inner diameter side of the coil end portion and the outer diameter side of the coil end portion. The angle formed by both ends of the arc portion of the bus bar and the center of the stator core is θ1, and the angle formed by both ends of the arc portion of the adjacent bus bar and the center of the stator core is θ2. The stator of the rotary electric machine according to claim 1 , wherein a part of θ1 and θ2 are arranged so as to overlap each other. The rotation according to claim 1 or 2 , wherein a reference plane perpendicular to the central axis of the stator core is formed on the bus bar, and at least a part of the reference planes of the bus bar are arranged on the same plane. Electric stator. The stator of a rotary electric machine according to any one of claims 1 to 3 , wherein the bus bar arranged on the inner diameter side of the coil end portion is arranged outside the inner diameter of the stator. The stator of a rotary electric machine according to any one of claims 1 to 4 , wherein the surface of the bus bar has an insulating coating except for the terminal portion. The rotary electric machine according to any one of claims 1 to 5 , wherein the bus bar is made of a conductor having a rectangular cross section, and the surface on the long side of the cross section is connected to the coil end portion. stator. The bus bar is folded to the outer diameter side of the coil end portion with the first bent portion bent with the short side of the cross section of the bus bar as a bent curved surface and the long side of the cross section of the first bent portion as a bent curved surface. The stator of a rotary electric machine according to claim 6 , wherein a bent portion composed of a bent second bent portion is provided at both ends.

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