JP2021175230A - Rotary electric machine - Google Patents

Abstract

To provide a rotary electric machine capable of easily cooling a stator and a rotor.SOLUTION: A rotary electric machine is of an axial type in which a rotor and a stator are arranged so as to face each other in a shaft direction of a rotation shaft of a rotor. The stator includes coil wires of a plurality of phases. The coil wire of each phase includes a circumferentially extending portion extending in a circumferential direction of the stator, and a radially extending portion extending in a radial direction of the stator. The circumferentially extending portion of the coil wire of an arbitrary phase of the coil wires of a plurality of phases extends partially overlapping with the coil wire of the other phase so as to extend beyond the coil wire of the other phase in the circumferential direction. A length in the axial direction of the circumferentially extending portion of the coil wire of any phase is shorter than that in the radial direction. An axial length of the circumferentially extending portion of the coil wire of any phase is shorter than that of the radially extending portion of the coil wire of at least one phase among the coil wires of the plurality of phases. Thus, a step formed on a surface of the coil wire is reduced.SELECTED DRAWING: Figure 6

Description

The technique disclosed herein relates to a rotary electric machine. In particular, the present specification relates to an axial type rotary electric machine in which the rotor and the stator are arranged so as to face each other in the axial direction of the rotation shaft of the rotor.

Patent Document 1 discloses an axial rotary electric machine in which a rotor (referred to as a magnet assembly in Patent Document 1) and a stator are arranged so as to face each other in the axial direction of the rotation axis of the rotor. In the rotary electric machine of Patent Document 1, the stator includes a three-phase coil wire (referred to as a conductor in Patent Document 1). The coil wire of Patent Document 1 includes a radial extending portion extending in the radial direction of the stator and a circumferential extending portion extending in the circumferential direction of the stator. In Patent Document 1, the radial extending portion of the three-phase coil is arranged adjacent to the circumferential direction of the stator, and the circumferential extending portion of the three-phase coil is arranged so as to overlap in the axial direction. ..

Special Table 2019-517771

The stator and rotor of the rotary electric machine generate heat during operation. When the rotor of the rotary electric machine rotates, the surrounding air flows through the gap between the coil wire of the stator and the axial direction of the rotor. This causes the fluid to cool the coil wire and rotor. In the coil wire of Patent Document 1, the radial extending portions of the three-phase coil wire are arranged adjacent to each other in the circumferential direction of the stator. Further, in the coil wire of Patent Document 1, the peripheral extending portion of the coil wire of each phase overlaps with the coil wire of the other phase in the axial direction. As a result, the coil wire of each phase goes around the coil wire of the other phase in the circumferential direction.

The boundary between the plurality of radial extension portions arranged adjacent to each other in the circumferential direction of the stator and the plurality of circumferential extension portions arranged in the axial direction of the stator extends in the axial direction of the rotor. A step is formed. When a step is formed at the boundary between the radial extension portion and the circumferential extension portion of the coil wire, the air passing through the axial gap between the coil wire and the rotor collides with the step. As a result, air stays in the axial gap between the coil wire and the rotor. Therefore, in the rotary electric machine of Patent Document 1, it is difficult to cool the stator and the rotor including the coil wire. The present specification provides a rotary electric machine that can easily cool the stator and the rotor by reducing the step formed at the boundary between the radial extension portion and the circumferential extension portion of the coil wire.

The rotary electric machine disclosed in the present specification is an axial type in which a rotor and a stator are arranged so as to face each other in the axial direction of the rotation shaft of the rotor. The stator includes a multi-phase coil wire. The coil wire of each phase includes a circumferential extending portion extending in the circumferential direction of the stator and a radial extending portion extending in the radial direction of the stator. The circumferentially extending portion of the coil wire of any phase of the plurality of phases of the coil wire partially overlaps the coil wire of the other phase in the axial direction, and the coil wire of the other phase. Is extended so as to exceed the circumferential direction. The axial length of the circumferential extension of the coil wire of any phase is shorter than the radial length. The axial length of the circumferential extension of the coil wire of any phase is the radial length of the coil wire of at least one of the plurality of phases of the coil wire. It is shorter than the axial length.

In the above-mentioned rotary electric machine, the axial length of the circumferential extension portion of any phase overlapping the coil wires of other phases in the axial direction is among the radial extension portions of the multi-phase coil wires. It is shorter than the axial length of the radial extension of at least one phase. In this configuration, the axial length of the circumferential extension can be shortened, the step formed at the boundary between the radial extension and the circumferential extension becomes smaller, and the gap between the coil wire and the rotor becomes smaller. The fluid is easy to pass through. As a result, the rotary electric machine described above tends to cool the coil wire and the rotor.

Further, in the rotary electric machine described above, the axial length of the circumferential extension portion of the coil wire of the arbitrary phase and the circumferential extension portion of the arbitrary phase overlap in the axial direction. The axial length of the circumferential extension portion of the coil wire of the other phase is the diameter of at least one phase of the radial extension portion of the coil wire of the plurality of phases, respectively. The length of the extending portion in the axial direction may be half or less.

As a result, the axial length of any phase overlapping in the axial direction and the circumferential extension of the other phase is the same as the axial length of the radial extension of at least one phase. can do.

In the rotary electric machine described above, the axial length of the circumferential extension portion of the coil wire of the arbitrary phase is the axial length of the circumferential extension portion of the coil wire of the plurality of phases. Of the radial extension portion of the plurality of phases of the coil wire, which is the maximum (longest) of the above, the radial extension portion having the maximum (longest) axial length. It may be shorter than the axial length.

As a result, the axial length of any phase overlapping in the axial direction and the circumferential extending portion of the other phase is set to the axial length of the radial extending portions of the multi-phase coil wires. It can be shrunk compared to the radial extension where the maximum (longest) is.

In the rotary electric machine described above, the axial length of the circumferential extension portion of the coil wire of the arbitrary phase is the axial direction of the radial extension portion of the coil wire of the plurality of phases. May be shorter than the axial length of the radial extension portion, which has the minimum (shortest) length.

As a result, the axial length of any phase overlapping in the axial direction and the circumferential extending portion of the other phase is set to the axial length of the radial extending portions of the multi-phase coil wires. It can be shrunk compared to the radial extension where the size is the smallest (shortest).

In the rotary electric machine described above, the axial length of the circumferential extension portion of the coil wire of the arbitrary phase is the axial direction of the radial extension portion of the coil wire of the plurality of phases. The length of the radial extension portion may be half or less of the axial length of the minimum (shortest) portion.

As a result, the axial length of any phase overlapping in the axial direction and the circumferential extending portion of the other phase is set to the minimum (shortest) axial length of the radial extending portions. It can be the same as the axial length of a certain radial extension.

The rotary electric machine described above may further include a housing arranged so as to face the stator in the axial direction.

By reducing the step at the boundary between the radial extending portion and the circumferential extending portion, the housing can be arranged at a position closer to the radial extending portion of the coil wire. As a result, the size of the rotary electric machine including the housing can be reduced.

In the rotary electric machine described above, the coil wire of any phase among the coil wires of the plurality of phases may be composed of litz wire. Thereby, the shapes of the radial extending portion and the circumferential extending portion of the coil wire can be freely formed. The axial length of the circumferential extension can be easily shortened.

The perspective view of the rotary electric machine of an Example is shown. The exploded perspective view of the rotary electric machine of an Example is shown. A cross-sectional view taken along the line III-III of FIG. 1 is shown. The enlarged view of the range surrounded by the broken line IV of FIG. 2 is shown. A cross-sectional view taken along the line VV of FIG. 4 is shown. A cross-sectional view taken along the line VI-VI of FIG. 4 is shown. A perspective view of a part of the coil wire is shown.

The axial gap type rotary electric machine 100 will be described with reference to FIGS. 1 and 2. The axial gap type rotary electric machine 100 can be used as a generator and a motor. The axial gap type rotary electric machine 100 includes a rotor 2 and a stator 10. The stator 10 has a coil 20 and a coil plate 12. The coil 20 is an aggregate of three-phase coil wires (U-phase coil wire 20U, V-phase coil wire 20V, W-phase coil wire 20W), and is housed in the coil plate 12. In the coil 20, the coil wires of each phase reciprocate in the radial direction 20D of the stator 10 and orbit the stator 10 in the circumferential direction 20R for 3 turns. In the following, for the sake of easy understanding of the explanation, the positive side of the coordinate axes in the drawing in the Z-axis direction may be simply expressed as "upper", and the opposite may be expressed as "lower". Further, although the axial gap type rotary electric machine 100 includes a housing 15 (see FIG. 3) that covers the stator 10, the housing 15 is not shown in FIGS. 1 and 2 for the sake of understanding. ..

The coil 20 (stator 10) has a coreless structure that does not have a stator core (yoke, teeth, etc.) that supports the coil wires 20U, 20V, and 20W of each phase. That is, the coil 20 is formed by the coil wires 20U, 20V, and 20W of each phase rotating in the circumferential direction 20R while reciprocating in the radial direction 20D. As shown in FIG. 2, one end of the U-phase coil wire 20U is connected to the U-phase terminal 26U, and one end of the V-phase coil wire 20V is connected to the V-phase terminal 26V. One end is connected to the W phase terminal 26W. Further, the other ends of the coil wires 20U, 20V and 20W of each phase are connected to each other by a connection portion 26. As shown in FIG. 1, the outer diameter of the coil 20 is larger than the outer diameter of the first rotor 2a. Further details of the coil 20 will be described later.

The rotor 2 includes a pair of a first rotor 2a and a second rotor 2b. The first rotor 2a arranged above the stator 10 includes a first rotor plate 4a and a first permanent magnet 6a. A shaft hole 8a is provided in the center of the first rotor 2a. The shaft hole 8a penetrates the first rotor plate 4a of the first rotor 2a in the axis 30 direction. The axis 30 passes through the center of the shaft hole 8a in the vertical direction (that is, the Z-axis direction). Four mounting holes 9a are provided around the shaft hole 8a. The second rotor 2b arranged below the stator 10 includes a second rotor plate 4b and a second permanent magnet 6b. A shaft boss 8b is provided at the center of the second rotor plate 4b of the second rotor 2b. The shaft portion boss 8b extends in the axis 30 direction (that is, in the vertical direction). The shaft boss 8b has four mounting seats 9b. Each of the four mounting seats 9b is separated by 90 degrees in the circumferential direction and extends from the side surface of the shaft portion boss 8b in a direction orthogonal to the axis 30. A mounting hole 9c is provided on the upper surface of each mounting seat 9b. The shaft portion boss 8b of the second rotor 2b inserts the shaft portion hole 8a of the first rotor 2a. As a result, the mounting holes 9c of the second rotor 2b and the mounting holes 9a of the first rotor 2a face each other. A screw (not shown) is inserted from the upper surface of the first rotor 2a through the mounting hole 9a of the first rotor 2a and screwed into the mounting hole 9c of the second rotor 2b. As a result, the first rotor 2a and the second rotor 2b are fixed. The first rotor 2a and the second rotor 2b have the same polarities (N pole, S pole) of the first permanent magnet 6a and the second permanent magnet 6b in the axis 30 direction (that is, the vertical direction) by a screw (not shown). In the state, they are fixed so that they cannot rotate relative to each other.

The relationship between the stator 10 and the rotor 2 will be described with reference to FIG. FIG. 3 shows a cross-sectional view of the axial gap type rotary electric machine 100 along the axis 30 direction. As described above, the shaft portion boss 8b of the second rotor 2b inserts the shaft portion hole 8a of the first rotor 2a. The upper surface of the mounting seat 9b of the shaft portion boss 8b comes into contact with the lower surface of the first rotor plate 4a of the first rotor 2a. As a result, the axial distance between the first rotor 2a and the second rotor 2b is maintained. As shown in FIG. 3, in the first rotor 2a and the second rotor 2b, permanent magnets 6a and 6b are arranged on both the upper and lower sides of the stator 10. The first rotor 2a and the second rotor 2b are arranged on the stator 10 so as to face each other in the direction of the axis 30. In other words, the stator 10 is arranged between the first rotor 2a and the second rotor 2b.

The coil 20 is arranged above the coil plate 12. As a result, the stator 10 is formed. As shown in FIG. 2, the stator 10 (that is, the coil 20 and the coil plate 12) has a through hole in the central portion, and the shaft portion boss 8b of the second rotor 2b inserts the through hole. As a result, the rotor 2 (first rotor 2a and second rotor 2b) rotates with respect to the stator 10. In FIG. 3, the shape of the coil 20 is schematically shown as a rectangle.

The axial gap type rotary electric machine 100 includes a housing 15. The housing 15 covers the stator 10 from above and below. As described above, the outer diameter of the first rotor 2a is smaller than the outer diameter of the coil 20. The end portion of the coil 20 in the X-axis direction (that is, the left-right direction in the drawing) does not face the end portion in the X-axis direction of the first rotor 2a in the Z direction. Although the details will be described later, at the end portion of the coil 20 on the outer side in the radial direction 20D, the coil wires of each phase extend in various directions. By not facing the outer end of the coil 20 in the radial direction 20D from which the coil wires of each phase extend in various ways with the first rotor 2a, the first permanent magnet 6a of the first rotor 2a and the outer side of the coil 20 in the radial direction 20D Prevents the generation of magnetic force between the ends of the. The housing 15 faces the end of the coil 20 in the X-axis direction protruding from the end of the first rotor 2a in the X-axis direction.

Although the details will be described later, the coil 20 has three-phase coil wires, and the coil wires of each phase are arranged so as to be offset in the circumferential direction of the stator 10. Currents with different cycles are passed through the coil wires of each phase. As a result, magnetic fields having different periods are generated in the coil wires of each phase. The first permanent magnets 6a and the second permanent magnets 6b of the rotor 2 rotate about the axis 30 by the magnetic force generated in the coil wires of each phase. In order to rotate the rotor 2 (first rotor 2a and second rotor 2b) and the stator 10, a gap C1 is provided between the first permanent magnet 6a of the first rotor 2a and the coil 20 in the axis 30 direction. There is. Similarly, a gap C2 is provided between the second permanent magnet 6b of the second rotor 2b and the coil plate 12 in the direction of the axis 30. The axis 30 is the rotation axis of the rotor 2, and can be regarded as the rotation axis of the stator 10 (coil 20).

When a current flows through the coil 20, the coil 20 generates heat. As shown by the broken line arrow in FIG. 3, the heat generated from the coil 20 is released to the outside of the axial gap type rotary electric machine 100 from the gap C1 between the coil 20 and the first permanent magnet 6a. Further, the heat of the coil 20 is cooled by the air flowing in from the outside of the axial gap type rotary electric machine 100. That is, the coil 20 is cooled by the air flowing through the gap C1 between the coil 20 and the first permanent magnet 6a. Similarly, the coil 20 is cooled by the air flowing through the gap C2 between the coil plate 12 and the second permanent magnet 6b.

If there is a step extending in the direction of the axis 30 on the surface of the coil 20, the air flowing through the gap C1 collides with the step and stays there. As a result, the heat of the coil 20 remains in the interval C1, and the coil 20 is hard to be cooled. Hereinafter, the structure adopted by the axial gap type rotary electric machine 100 of the embodiment in order to reduce the step on the surface of the coil 20 will be described.

The structure of the U-phase coil wire 20U will be described with reference to FIG. In FIG. 4, the range surrounded by the broken line IV in FIG. 2 is expanded, and only the U-phase coil wire 20U is shown. In FIG. 4, the rotation axis (that is, the axis 30) of the rotor 2 is located on the positive side in the Y-axis direction (that is, the lower side of the paper surface) so as to be orthogonal to the paper surface. The lower side of the drawing of FIG. 4 (that is, the positive side in the Y-axis direction) is the inside of the stator 10 in the radial direction 20D, and the opposite is the outside of the stator 10 in the radial direction 20D. As shown in FIG. 4, the U-phase coil wire 20U orbits in the circumferential direction 20R while reciprocating between the inside and the outside in the radial direction. Although the U-phase coil wire 20U is mainly described in the present specification, the coil wires of other phases (that is, the V-phase coil wire 20V and the W-phase coil wire 20W) also have the same structure. ..

The U-phase coil wire 20U includes a plurality of radial extending portions 21U, a plurality of inner circumferential extending portions 22U, and a plurality of outer circumferential extending portions 23U. Each radial extending portion 21U extends in the radial direction 20D of the coil 20 (stator 10). Each inner peripheral extending portion 22U extends in the circumferential direction 20R of the coil 20 (stator 10). The inner circumferential extending portion 22U connects two adjacent radial extending portions 21U and 21U inside the radial direction 20D. Each outer peripheral extending portion 23U extends in the circumferential direction 20R of the coil 20 (stator 10). The outer circumferential extending portion 23U connects two adjacent radial extending portions 21U and 21U on the outer side in the radial direction 20D.

As shown in FIG. 4, the U-phase coil wire 20U reciprocates in the radial direction 20D and orbits around the axis 30 (see FIG. 3) of the coil 20 in the circumferential direction 20R for three turns. That is, the inner ends of all the radial extending portions 21 of the U-phase coil wire 20U are connected to the inner peripheral extending portions 22U. The outer ends of all the radial extension 21 of the U-phase coil wire 20U are connected to the outer circumferential extension 23U. To aid understanding, in FIG. 4, the coil wire U1 of the first turn of the U-phase coil wire 20U is shown by the hatching of the upper right diagonal line, and the coil wire U2 of the second turn of the U-phase coil wire 20U is shown by the hatching of the upper left diagonal line. ing. The coil wire U3 on the third turn of the U-phase coil wire 20U is shown by dotting.

The coil wire U1 of the first turn of the U-phase coil wire 20U passes through the uppermost side (that is, the front side of the paper surface). The coil wire U2 of the second turn of the U-phase coil wire 20U passes below the coil wire U1 of the first turn (that is, the back side of the paper surface). As shown in FIG. 4, the radial extending portions 21U of the coil wire U1 of the first turn and the coil wire U2 of the second turn partially overlap each other in the axial direction. In other words, the coil wire U1 and the coil wire U2 orbit the positions deviated from each other in the direction of the axis 30 in FIG.

The coil wire U3 on the third turn of the U-phase coil wire 20U orbits the outside of the coil wire U2 in the radial direction 20D. As shown in FIG. 5, the radial extending portion 21U of the coil wire U3 is arranged adjacent to the radial extending portion 21U of the coil wire U2 and the circumferential direction 20R.

The inner circumferential extending portion 22U of the coil wire U1 on the first turn passes through the outermost side of the inner circumferential extending portion 22U of the U-phase coil wire 20U from the first turn to the third turn in the radial direction 20D. There is. The inner circumferential extending portion 22U of the coil wire U2 on the second turn passes through the innermost side of the inner circumferential extending portion 22U of the U-phase coil wire 20U from the first turn to the third turn in the radial direction 20D. There is. The inner circumferential extending portion 22U of the coil wire U3 on the third turn is the diameter of the inner circumferential extending portion 22U of the coil wire U1 on the first turn and the inner circumferential extending portion 22U of the coil wire U2 on the second turn. Passing between directions 20D.

The outer circumferential extending portion 23U of the coil wire U1 on the first turn passes through the innermost side of the outer circumferential extending portion 23U of the U-phase coil wire 20U from the first turn to the third turn in the radial direction 20D. There is. The outer circumferential extending portion 23U of the coil wire U3 on the third turn passes through the outermost side of the outer circumferential extending portion 23U of the U-phase coil wire 20U from the first turn to the third turn in the radial direction 20D. There is. The outer circumferential extending portion 23U of the coil wire U2 on the second turn is the diameter of the outer circumferential extending portion 23U of the coil wire U1 on the first turn and the outer circumferential extending portion 23U of the coil wire U3 on the third turn. It passes between the 20D directions. In this way, the U-phase coil wire 20U moves around the axis 30 (see FIG. 3) of the coil 20 by shifting the position through which the coil wire of each turn passes in the axis 30 direction, the circumferential direction 20R, and the radial direction 20D. It orbits 20R in the circumferential direction for 3 turns.

The U-phase coil wire 20U is composed of a litz wire. In the litz wire, an electric wire obtained by twisting a plurality of thin conducting wires is arranged in a mold, and each electric wire is joined by heat to form a coil wire shape. Therefore, the litz wire has a high degree of freedom in shape. The cross-sectional shape of the litz wire can be changed for each part. The inner circumferential extending portion 22U and the outer circumferential extending portion 23U of the U-phase coil wire 20U have a flat cross-sectional shape as if compressed in the axial direction 30 direction. In the following, with reference to FIGS. 4 to 6, the width (that is, the length of the radial direction 20D or the circumferential direction 20R) and the height (that is, the length of the radial direction 20D or the circumferential direction 20R) of the cross-sectional shape provided in each part of the U-phase coil wire 20U (that is, that is). The length in the direction of the axis 30) will be described.

As shown in FIG. 4, the length of the radial extending portion 21U of the U-phase coil wire 20U in the circumferential direction 20R is the width W. As shown in FIG. 5, the cross-sectional shape of the radial extending portion 21U is circular. That is, the radial extending portion 21U has a circular cross-sectional shape having a diameter W. On the other hand, as shown in FIG. 4, the radial length of the inner circumferential extending portion 22U of the coil wire of each turn is a width of 2W. That is, the width W of the radial extending portion 21U is half the width 2W of the inner peripheral extending portion 22U. The width W of the radial extending portion 21U is shorter than the width 2W of the inner peripheral extending portion 22U. The width of the inner end of the radial extending portion 21U increases as it approaches the inner peripheral extending portion 22U. The width of the inner end of the radial extending portion 21U of the coil wire U1 on the first turn is 2W at the boundary between the radial extending portion 21U of the coil wire U1 and the inner circumferential extending portion 22U. The width of the inner end of the radial extending portion 21U of the coil wire U2 on the second turn and the coil wire U3 on the third turn is the outer end of the radial extending portion 22U of the inner circumferential extending portion 22U on the first turn in the radial direction 20D. The width is 2 W in the vicinity of the portion. That is, the positions where the coil wires of each turn have a width of 2 W are aligned in the radial direction 20D.

Similarly, the radial length of the outer peripheral extending portion 23U is a width of 2W. The width W of the radial extending portion 21U is half the width of the outer peripheral extending portion 23U. The width W of the radial extending portion 21U is shorter than the width W of the outer peripheral extending portion 23U. The width of the outer end of the radial extension 21U increases as it approaches the outer circumferential extension 23U. The width of the outer end portion of the outer circumferential extending portion 23U on the first turn in the radial direction 20D is 2W at the boundary between the radial extending portion 21U of the coil wire U1 and the outer circumferential extending portion 23U. The width of the outer end of the radial extension 21U of the coil wire U2 on the second turn and the coil wire U3 on the third turn is the inner end of the inner peripheral extension 22U of the first turn in the radial direction 20D. The width is 2 W at a position where the portion is shifted in the circumferential direction by 20R. That is, the positions where the coil wires of each turn have a width of 2 W are aligned in the radial direction 20D.

The height of the U-phase coil wire 20U (that is, the length in the axis 30 direction) will be described with reference to FIG. As described above, since the cross-sectional shape of the radial extending portion 21U of the U-phase coil wire 20U is a circle having a diameter W, the length in the axis 30 direction is the height W. On the other hand, as shown in FIG. 6, the length of the coil wire U3 extending in the inner circumferential direction 22U in the axis 30 direction is a height W / 2. That is, the length of the coil wire U3 in the inner circumferential direction extending portion 22U in the axis 30 direction is half the length of the coil wire U3 in the radial extending direction portion 21U in the axis 30 direction. As shown in FIG. 6, the length of the inner end portion of the radial extending portion 21U of the coil wire U3 in the axial direction 30 direction becomes shorter as it approaches the inner peripheral extending portion 22U of the coil wire U3. The length of the inner end of the radial extending portion 21U in the axis 30 direction is a height W / 2 near the radial outer boundary of the inner circumferential extending portion 22U of the coil wire U1.

Similarly, the length of the coil wire U3 extending in the outer circumferential direction 23U in the axis 30 direction is the height W / 2. The length of the coil wire U3 in the outer circumferential direction extending portion 23U in the axis 30 direction is half the length of the coil wire U3 in the radial extending direction portion 21U in the axis 30 direction. The length of the outer end of the coil wire U3 in the radial direction 21U in the axis 30 direction becomes shorter as it approaches the outer circumferential extension 23U of the coil wire U3. The length of the inner end of the coil wire U3 in the radial direction 21U in the axial direction 30 is the height W / 2 at the boundary between the radial extension 21U of the coil wire U3 and the outer circumferential extension 23U. It becomes. In FIG. 6, the lengths of the inner circumferential extending portion 22U of the coil wire U1 and the outer circumferential extending portion 23U of the coil wire U3 on the first turn in the axial direction 30 direction have been described. The length of the other (second and third turns) of the U-phase coil wire 20U in the inner circumferential direction and the outer circumferential direction is the same as that of the coil wire U1. And the explanation is omitted.

As described above, the width W of the radial extending portion 21U of the U-phase coil wire 20U is half the width 2W of the inner circumferential extending portion 22U and the outer circumferential extending portion 23U. On the other hand, the height W of the radial extending portion 21U of the U-phase coil wire 20U is twice as long as the height W / 2 of the inner circumferential extending portion 22U and the outer circumferential extending portion 23U. .. That is, the cross-sectional area of the radial extending portion 21U in the cross section orthogonal to the radial direction 20D and the cross-sectional area of the inner circumferential extending portion 22U in the cross section orthogonal to the circumferential direction 20R are substantially the same. The cross-sectional area of the radial extending portion 21U in the cross section orthogonal to the radial direction 20D and the cross-sectional area of the outer peripheral extending portion 23U in the cross section orthogonal to the circumferential direction 20R are substantially the same. As described above, the coil wire of each phase is composed of a litz wire manufactured by twisting a thin conductor wire. Since the cross-sectional area of the radial extending portion 21U is substantially the same as the cross-sectional area of the inner circumferential extending portion 22U and the outer circumferential extending portion 23U, the inner circumferential extending portion 22U and the outer circumferential extending portion 23U Can accommodate the same number of electric wires as the radial extending portion 21U.

Next, the relationship between the U-phase coil wire 20U and the coil wires of other phases (that is, the V-phase coil wire 20V and the W-phase coil wire 20W) will be described with reference to FIGS. 5 and 6.

In the coil 20, similarly to the U-phase coil wire 20U, the V-phase coil wire 20V and the W-phase coil wire 20W also orbit around the axis 30 (see FIG. 3) of the coil 20 in the circumferential direction 20R for three turns. The V-phase coil wire 20V and the W-phase coil wire 20W pass through positions deviated from the U-phase coil wire 20U in the circumferential direction 20R. In FIGS. 5 and 6, the V-phase coil wire 20V is indicated by a broken line, and the W-phase coil wire 20W is indicated by a two-dot chain line. Further, in FIGS. 5 and 6, similarly to the U-phase coil wire 20U of FIG. 4, the coil wire of the first turn is indicated by the hatching of the upper right diagonal line, and the coil wire of the second turn is indicated by the hatching of the upper left diagonal line. The coil wire at the turn is shown by dotting.

As shown in FIG. 5, the coil wire V1 of the first turn of the V-phase coil wire 20V is arranged above the coil wire U3 of the third turn of the U-phase coil wire 20U described above (that is, in the direction of the axis 30). ing. The coil wire V2 of the second turn of the V-phase coil wire 20V is arranged on the negative side in the X-axis direction (that is, the circumferential direction 20R) of the coil wire V1 of the first turn of the V-phase coil wire 20V. The coil wire V3 on the third turn of the V-phase coil wire 20V is arranged below the coil wire V2 on the second turn of the V-phase coil wire 20V (that is, in the direction of the axis 30). In this way, the V-phase coil wire 20V shifts the position through which the coil wire of each turn passes in the axial direction 30 direction and the circumferential direction 20R so that the coil 20 is rotated around the axis 30 (see FIG. 3) in the circumferential direction 20R. It has been lapped for 3 turns.

The coil wire W1 of the first turn of the W-phase coil wire 20W is arranged on the negative side in the X-axis direction (that is, the circumferential direction 20R) of the coil wire V2 of the second turn of the V-phase coil wire 20V. The coil wire W2 of the second turn of the W-phase coil wire 20W is arranged below the coil wire W1 of the first turn of the W-phase coil wire 20W (that is, in the direction of the axis 30). The coil wire W3 on the third turn of the W-phase coil wire 20W is arranged on the negative side in the X-axis direction (that is, the circumferential direction 20R) of the coil wire W2 on the second turn of the W-phase coil wire 20W. In this way, the W-phase coil wire 20W shifts the position through which the coil wire of each turn passes in the axial direction 30 direction and the circumferential direction 20R so that the coil 20 is rotated around the axis 30 (see FIG. 3) in the circumferential direction 20R. It has been lapped for 3 turns.

In this way, in the coil 20, the coil wires of each turn of the coil wires of each phase are passed by shifting them in the axial direction 30 direction and the circumferential direction 20R. The position where the coil wire of each turn of each phase of the coil wire passes may be shifted in three layers in the axis 30 direction, or may be further shifted in the circumferential direction 20R so as not to overlap in the axis 30 direction. ..

When the radially extending portions of each phase are arranged so as to be offset in the vertical direction as in the coil 20, the axial central portion of the coil 20 is arranged in the vertical direction (that is, the axis of FIG. 3) as shown in FIG. The length H in the 30 direction) is the length (that is, the height 2W) in the 30 direction of the axis line for two radial extending portions.

As shown in FIG. 6, above the radial extension portion 21U of the coil wire U3 on the third turn of the U-phase coil wire 20U (that is, in the direction of the axis 30), the first turn of the V-phase coil wire 20V A radial extending portion 21V of the coil wire V1 is arranged. The radial extending portion 21V of the coil wire V1 extends inward in the radial direction 20D and is connected to the inner circumferential extending portion 22V of the coil wire V1. Above the radial 20D inner end of the coil wire V1 radial extension 21V (that is, in the axis 30 direction), the inner circumferential extension of the coil wire U1 of the first turn of the U-phase coil wire 20U. 22U partially overlap. The radial 20D inner end of the radial extending portion 21V of the coil wire V1 is an inner circumferential extending portion with the inner circumferential extending portion 22U of the coil wire U1 moving downward (that is, in the axis 30 direction). Connect to 22V. The inner circumferential extending portion 22U of the coil wire U1 is an adjacent radial extending portion of the coil wire U1 of the first turn of the U-phase coil wire 20U with the coil wire V1 facing upward (that is, in the direction of the axis 30). Connect 21U (see FIG. 4).

The radial extending portion 21U of the coil wire U3 extends inward in the radial direction 20D and is connected to the inner circumferential extending portion 22U of the coil wire U3. Above the radial 20D inner end of the coil wire U3 in the radial direction 21U (that is, in the axis 30 direction), the inner circumferential extension 22V of the coil wire V3 on the third turn of the V-phase coil wire 20V. Partially overlap. The radial 20D inner end of the radial extending portion 21U of the coil wire U3 is an inner circumferential extending portion with the inner circumferential extending portion 22V of the coil wire V3 moving downward (that is, in the axis 30 direction). Connect to 22U. The inner circumferential extending portion 22V of the coil wire V3 is an adjacent radial extending portion of the coil wire V3 on the third turn of the V-phase coil wire 20V with the coil wire U3 facing upward (that is, in the direction of the axis 30). Connect 21V (see FIG. 5). As a result, as shown in FIG. 6, four coil wires may partially overlap in the vertical direction (that is, in the axial direction 30 direction) inside the radial direction 20D. That is, inside the radial direction 20D in which the circumferential extension portion of the coil wire of each phase extends in the circumferential direction, the number of coil wires overlapping in the vertical direction (that is, the axis 30 direction) is the radial central portion of the coil 20. It will be more than the two.

Similarly, on the outer side of the radial direction 20D (that is, on the right side of the paper surface), the radial extending portion 21V of the coil wire V1 extends outward in the radial direction 20D and is connected to the outer peripheral extending portion 23V of the coil wire V1. There is. Above the radial 20D outer end of the coil wire V1 radial extension 21V (that is, in the axis 30 direction), the outer circumferential extension of the coil wire W1 on the first turn of the W-phase coil wire 20W. 23W partially overlaps. The radial 20D outer end of the radial extending portion 21V of the coil wire V1 is an outer circumferential extending portion with the outer circumferential extending portion 23W of the coil wire W1 moving downward (that is, in the axis 30 direction). Connect to 23V. The outer circumferential extending portion 23W of the coil wire W1 is an adjacent radial extending portion of the coil wire W1 of the first turn of the W-phase coil wire 20W with the coil wire V1 facing upward (that is, in the direction of the axis 30). Connect 21W (see FIG. 5).

Further, on the outer side of the radial direction 20D, the radial extension portion 21U of the coil wire U3 on the third turn of the U-phase coil wire 20U extends outward in the radial direction 20D and is connected to the outer peripheral direction extension portion 23U. .. Above the radial 20D outer end of the coil wire U3 radial extension 21U (that is, in the axis 30 direction), the outer circumferential extension 23W of the coil wire W2 on the second turn of the W-phase coil wire 20W. Partially overlap. Further, above the radial 20D outer end of the radial extending portion 21U of the coil wire U3, the outer circumferential extending portion 23W of the coil wire W3 on the third turn of the W-phase coil wire 20W is also partially. overlapping. The radial 20D outer end of the radial extension 21U of the coil wire U3 is the outer circumference of the coil wire W2 and the outer circumferential extension 23W of the coil wire W3 with the downward direction (that is, the axis 30 direction). Connect to the directional extension 23U. The outer circumferential extension portion 23W of the coil wire W2 is an adjacent radial extension portion of the coil wire W2 on the second turn of the W-phase coil wire 20W with the coil wire U3 facing upward (that is, in the direction of the axis 30). Connect 21W (see FIG. 5). The outer circumferential extending portion 23W of the coil wire W3 moves the coil wire U3 upward (that is, in the direction of the axis 30), and the adjacent radial extending portion 21W of the coil wire W3 on the third turn (see FIG. 5). To connect. As a result, on the outer side of the radial direction 20D, the four coil wires may partially overlap in the vertical direction (that is, the axis 30 direction). That is, on the outer side of the radial direction 20D in which the outer circumferential extension portion of the coil wire of each phase extends in the circumferential direction, the number of coil wires overlapping in the vertical direction (that is, the axis 30 direction) is the radial center of the coil 20. It is more than the two parts.

As described above, the length of the U-phase coil wire 20U in the inner circumferential direction extending portion 22U and the outer circumferential direction extending portion 23U in the axis 30 direction is a height W / 2. Further, the lengths of the inner circumferential extending portion and the outer circumferential extending portion of each phase in the axial direction 30 are also the height W / 2. Therefore, among the circumferentially extending portions of the three-phase coil wires, the length in the axial direction 3-direction of the circumferentially extending portion having the maximum length in the axis 30 direction is W / 2. As shown in FIG. 5, the cross-sectional shapes of the radial extending portions 21U, 21V, 21W of each phase are the same, and their lengths in the axial direction 30 are also the same. That is, the radial extension portions having the maximum length in the axis 30 direction are the radial extension portions 21U, 21V, 21W of each phase, and the radial extension portions having the minimum length in the axis 30 direction. Also, the radial extending portions 21U, 21V, 21W of each phase. That is, the lengths (that is, height W / 2) of the inner circumferential extending portion 22U and the outer circumferential extending portion 23U in the axial direction 30 are the radial extending portions 21U, 21V of the three-phase coil wires. Of the 21W, the length in the axial direction 30 direction is the maximum, which is less than half the length in the axial direction 30 direction (that is, the height W) of the radially extending portion. Similarly, the length (that is, height W / 2) of the inner circumferential extending portion 22U and the outer circumferential extending portion 23U in the axis 30 direction is the radial extending portions 21U, 21V of the three-phase coil wire. , 21W, which is less than half the length in the axial direction 30 direction (that is, the height W) of the radial extending portion having the minimum length in the axial direction 30 direction. As a result, as shown by the outer circumferential extending portion 23W of the coil wire W2 and the outer circumferential extending portion 23U of the coil wire U3 in FIG. 6, the axial lines 30 direction of the two circumferential extending portions overlapping each other. Is equivalent to the radial extending portion 21U of one coil wire U3. As a result, the step at the boundary between the radial extending portion 21U and the outer circumferential extending portion 23U can be reduced, and the axis 30 of the upper surface of the radial extending portion 21U and the upper surface of the outer circumferential extending portion 23U can be reduced. The heights in the directions can be made equal.

By changing the height of the coil wires in the axis 30 direction in this way, it is possible to reduce the steps generated inside and outside the radial 20D where the number of coil wires overlapping in the axis 30 direction is large. As a result, as shown in FIG. 6, the height of the portion where the four coil wires overlap in the axis 30 direction can be suppressed in the axis 30 direction. As a result, as shown in FIG. 6, the gap between the outer circumferential extending portion 23W of the coil wire W1 and the housing 15 in the axial direction 30 direction is not locally narrowed. As shown by the broken line arrow in FIG. 6, air easily passes through the gap C1. That is, the axial gap type rotary electric machine 100 (see FIG. 1) of the embodiment can easily cool the coil 20 and the rotor 2 (see FIG. 3).

Further, in the above-described embodiment, as shown in FIGS. 4 and 6, the height of the end portion of the radial extending portion in the radial direction 20D in the axial direction 30 is W / 2, and the width is 2 W. .. In this way, the width of the radial 20D end of the radial extension where the inner circumferential extension and the outer circumferential extension of each phase overlap in the axis 30 direction is widened and the height is lowered. , The step formed at the end of the radial extending portion can be reduced.

The shapes of the radial extending portion 21U and the outer peripheral extending portion 23U will be further described with reference to FIG. 7. In FIG. 7, the cross-sectional shape of each portion of the U-phase coil wire 20U is shown by hatching. As shown in FIG. 7, the cross section of the radial extending portion 21U is circular. In the cross section of the radial extending portion 21U, the length in the axis 30 direction is the height W, and the length in the circumferential direction is the width W. The height of the U-phase coil wire 20U gradually decreases and the width increases as it goes outward in the radial direction (that is, on the right side of the drawing). Then, in the cross section of the outer peripheral extending portion 23U connecting the two radial extending portions 21U, the length in the axis 30 direction is the height W / 2, and the length in the circumferential direction is the width 2W. In this way, the U-phase coil wire 20U gradually changes its cross-sectional shape, and the height of the outer circumferential extending portion 23U overlapping the coil wires of the other phases in the axial direction 30 direction is lowered in the axial direction 30 direction. As a result, it is possible to prevent the length of the portion where the coil wires overlap in the axis 30 direction from increasing in the axis 30 direction. The radial section for changing from the circular cross section of the radial extending portion 21U to the flat cross section of the outer circumferential extending portion 23U may differ depending on the site, or the cross section may be changed in a shorter section. ..

Although the examples have been described in detail above, these are merely examples and do not limit the scope of claims. The techniques described in the claims include various modifications and modifications of the specific examples illustrated above. Modifications of the above-described embodiment are listed below.

(Modification 1) In the axial gap type rotary electric machine 100 of the above-described embodiment, the U-phase coil wire 20U, the V-phase coil wire 20V, and the W-phase coil wire 20W of the three-phase coil wires have the same shape. ing. Therefore, the height of the radial extending portion of each phase in the axis 30 direction is the same. Similarly, the height of the inner peripheral extending portion of each phase in the axial direction 30 direction is the same, and the height of the outer peripheral extending portion of each phase in the axial direction 30 direction is the same. In the modified example, instead of this, the shape of each part of the coil wire may be different for each phase or each part.

(Modification 2) In the above-described embodiment, the height of all the circumferential extending portions in the axis 30 direction is lower than the height of all the radial extending portions in the axis 30 direction. It is not limited to the configuration. In the second modification, the circumferential extension portion (for example, the inner circumferential extension portion 22U of the U phase) of the coil wire 20U of any phase among the coils 20 of the plurality of phases (U phase, V phase and W phase) The radial extension portion of the coil wire 20U of at least one phase of the coils 20 having a plurality of phases (U phase, V phase and W phase) in the length of the axis 30 direction (for example, the radial extension portion of the U phase). The configuration may be shorter than the length in the direction of the axis 30 of 21U). In other portions, there may be a portion in which the height of the circumferential extending portion in the axis 30 direction is higher than the height of the radial extending portion in the axis 30 direction.

(Modification 3) Among the circumferential extending portions of the coils 20 of a plurality of phases (U phase, V phase and W phase), the circumferential extending portion having the highest height in the axial direction 30 direction (for example, the inside of the U phase). The height of the circumferential extending portion 22U) in the axis 30 direction is the highest diameter of the radial extending portions of the multiple-phase (U-phase, V-phase, and W-phase) coils 20 in the axis 30 direction. The height of the directional extending portion (for example, the radial extending portion 21U of the U phase) may be shorter than the height in the axis 30 direction. In other portions, there may be a portion in which the height of the circumferential extending portion in the axis 30 direction is higher than the height of the radial extending portion in the axis 30 direction.

(Modification Example 4) In the axial gap type rotary electric machine 100 of the above-described embodiment, the stator 10 is covered by the housing 15, but in the modification, the housing 15 may not be provided instead. ..

(Modification 5) In the axial gap type rotary electric machine 100 of the above-described embodiment, the rotor 2 includes a pair of a first rotor 2a and a second rotor 2b, but in the modification, instead of this, a first rotor 2b is provided. Only 1 rotor 2a may be provided.

Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of claims. The techniques described in the claims include various modifications and modifications of the specific examples illustrated above. The technical elements described in the present specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the techniques illustrated in the present specification or drawings can achieve a plurality of purposes at the same time, and achieving one of the purposes itself has technical usefulness.

2: Rotor 2a: 1st rotor 2b: 2nd rotor 4a: 1st rotor plate 4b: 2nd rotor plate 6a: 1st permanent magnet 6b: 2nd permanent magnet 8a: Shaft hole 8b: Shaft boss 9a, 9c : Mounting hole 9b: Mounting seat 10: Stator 12: Coil plate 15: Housing 20: Coil 20R: Circumferential direction 20U: U-phase coil wire 20V: V-phase coil wire 20W: W-phase coil wire 21U, 21V, 21W: Diameter Directional extension 22U, 22V, 22W: Inner circumferential extension 23U, 23V, 23W: Outer circumferential extension 24V: Radial flat 26: Connection 26U: U-phase terminal 26V: V-phase terminal 26W: W-phase terminal 30: Axis line 100: Axial gap type rotary electric machine

Claims (7)

An axial type rotary electric machine in which the rotor and the stator are arranged so as to face each other in the axial direction of the rotation axis of the rotor.
The stator includes a multi-phase coil wire.
The coil wire of each phase includes a circumferential extending portion extending in the circumferential direction of the stator and a radial extending portion extending in the radial direction of the stator.
The circumferentially extending portion of the coil wire of any phase of the plurality of phases of the coil wire partially overlaps the coil wire of the other phase in the axial direction, and the coil wire of the other phase. Is extended so as to exceed the circumferential direction.
The axial length of the circumferential extension of the coil wire of any phase is shorter than the radial length.
The axial length of the circumferential extension of the coil wire of any phase is the radial length of the coil wire of at least one of the plurality of phases of the coil wire. A rotating electric machine shorter than the axial length. The rotary electric machine according to claim 1.
The axial length of the circumferential extension of the coil wire of the arbitrary phase and the coil wire of the other phase in which the circumferential extension of the arbitrary phase overlaps in the axial direction. The axial length of the circumferential extension portion is the axial direction of the radial extension portion of at least one phase of the radial extension portions of the plurality of phases of the coil wire. A rotating electric machine that is less than half the length of. The rotary electric machine according to claim 1 or 2.
The axial length of the circumferential extension portion of the coil wire of the arbitrary phase is the maximum among the axial lengths of the circumferential extension portion of the coil wire of the plurality of phases. From the axial length of the radial extension portion, which is the longest) and has the maximum (longest) axial length of the radial extension portions of the plurality of phases of the coil wire. Also short, rotating electric machine. The rotary electric machine according to claim 3.
The axial length of the circumferential extension portion of the coil wire of the arbitrary phase is the minimum of the axial length of the radial extension portion of the coil wire of the plurality of phases ( A rotary electric machine that is shorter than the axial length of the radial extension portion (the shortest).
The rotary electric machine according to claim 4.
The axial length of the circumferential extension portion of the coil wire of the arbitrary phase is the minimum of the axial length of the radial extension portion of the coil wire of the plurality of phases ( A rotary electric machine having a minimum length of half or less of the axial length of the radial extending portion. The rotary electric machine according to any one of claims 1 to 5.
A rotary electric machine further comprising a housing arranged so as to face the axially extending portion of the stator in the circumferential direction. The rotary electric machine according to any one of claims 1 to 6.
A rotary electric machine in which the coil wire of any phase of the coil wires of the plurality of phases is composed of a litz wire.

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