JP6365516B2 - Stator and axial gap type rotating electric machine including the stator - Google Patents

Description

  The present invention relates to an axial gap type rotating electrical machine (motor, generator, or motor / generator).

  Conventionally, an axial gap type rotating electrical machine (hereinafter, referred to as an axial gap type rotating electrical machine) having a structure in which a stator and a rotor are opposed to each other via an air gap in the rotor axial direction and the stator and the rotor are housed in a hollow cylindrical case. (Abbreviated as rotating electric machine) is known.

  In this type of rotating electrical machine, for example, Patent Document 1 includes, as a stator, a plurality of stator cores arranged in the circumferential direction and coils wound around each stator core, and these stator cores and coils are integrated with resin. Some of them are provided with a stator molded in the above. According to this configuration, since the plurality of stator cores and the coils are integrally molded, there is an advantage that the structural stability is good and the productivity of the rotating electrical machine is improved.

JP 2014-17915 A

  However, the heat conductivity of the resin is not necessarily good, and in the structure such as Patent Document 1 in which the stator core and the coil are integrally molded with the resin, the cooling performance of the stator including the heat dissipation of the coil is poor. There is room for improvement.

  The present invention has been made in view of the above circumstances, and relates to a stator for an axial gap rotating electrical machine, and provides a technique capable of improving cooling performance while contributing to productivity improvement of the rotating electrical machine. With the goal.

In order to solve the above problems, the present invention is a stator of an axial gap type rotating electrical machine, which is formed of a plurality of stator cores arranged in the circumferential direction around a rotation axis, and a resin material having electrical insulation, A holding member that integrally holds a plurality of stator cores, and a coil that is attached to each of the plurality of stator cores, and the holding member is an inner cylinder portion that is positioned inside the plurality of stator cores arranged in the circumferential direction; An outer cylindrical portion positioned outside the plurality of stator cores, and a bobbin portion formed on the outer peripheral surface of the stator core in a state in which an end portion of the stator core in the axial direction of the rotating shaft is exposed to hold the stator core. , Connected to one end of the bobbin portion, the inner tube portion, and the outer tube portion in the axial direction, the bobbin portion, the inner tube portion, and And a end face which forms a groove between the cylindrical portion, wherein are integrally molded with a plurality of stator cores, the coil, the provided from the outside of the bobbin portion is attached to the stator core, the stator further wherein It includes a lid member that forms a closed space in which the coil is accommodated together with the holding member by being fixed to the holding member so as to close the groove portion, and the holding member can supply and discharge cooling liquid to the closed space A cooling fluid supply / discharge unit is provided .

  According to such a stator, since a plurality of stator cores are integrally held by the holding member, it is possible to contribute to improving the productivity of the rotating electrical machine, and the coils are attached to each stator core from the outside of the bobbin portion. Therefore, the heat dissipation performance of the coil is also ensured. Therefore, it is possible to improve the cooling performance of the stator while contributing to the productivity improvement of the axial gap type rotating electrical machine.

In addition, since the coolant can be circulated inside the stator (closed space) through the coolant supply / discharge portion, the cooling performance of the coil and the stator core can be improved. In addition, since the closed space to which the coolant is supplied is formed by fixing the lid member to the holding member so as to block the groove formed in the holding member, the contact between the holding member and the lid member There is no part where liquid leakage can occur other than the surface, and the liquid-tightness is high. Therefore, it becomes possible to prevent the leakage of the cooling liquid satisfactorily.

  In this case, it is preferable that the lid member is ultrasonically welded to the holding member.

  According to this configuration, since it is possible to fix the lid member and the holding member in close contact with each other without a gap, a high-level liquid can be obtained without interposing a seal member between the lid member and the holding member. It becomes possible to ensure the density.

  In addition, the stator is provided inside the inner cylinder portion in contact with the inner peripheral surface thereof, and an inner cylinder member that reinforces the holding member, and is in contact with the outer peripheral surface outside the outer cylinder portion. And an outer cylinder member that reinforces the holding member.

  According to this configuration, the structural stability of the stator can be increased, and as a result, the structural stability of the axial gap rotating electrical machine can be increased.

  In this case, it is preferable that the inner cylinder member and the outer cylinder member are formed of a metal material, and the inner cylinder member, the outer cylinder member, the plurality of stator cores, and the holding member are integrally formed.

  According to this configuration, the productivity of the stator is improved by eliminating the need for separately incorporating the inner cylinder member and the outer cylinder member in the stator manufacturing process.

  In the stator, it is preferable that the stator core and the holding member have the same linear expansion coefficient.

  According to this configuration, it is possible to suppress troubles such as breakage of the holding member due to the difference in the amount of thermal deformation between the stator core and the holding member.

  On the other hand, the axial gap type rotating electrical machine of the present invention is a rotor including a rotating shaft and a rotor main body that rotates together with the rotating shaft, and is arranged at a predetermined interval in the axial direction of the rotating shaft with respect to the rotor main body. One of the above stators is provided.

  According to this axial gap type rotating electric machine, since the stator as described above is provided, it is possible to achieve both improvement in productivity and improvement in cooling performance.

  As described above, according to the present invention, it is possible to improve the cooling performance while contributing to the productivity improvement of the axial gap type rotating electrical machine.

It is a disassembled perspective view of the axial gap type rotary electric machine which concerns on this invention. It is principal part sectional drawing of the said axial gap type rotary electric machine. FIG. 3 is a sectional view of the stator (a sectional view taken along line III-III in FIG. 2). It is principal part sectional drawing of the said axial gap type rotary electric machine which shows the fixation structure of a case and a stator. It is a perspective view which shows a stator core assembly. It is a top view which shows a stator core assembly. FIG. 7 is a cross-sectional view (a cross-sectional view taken along line VII-VII in FIG. 6) showing the stator core assembly.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is an exploded perspective view of an axial gap type rotating electrical machine (axial gap type rotating electrical machine to which the stator of the present invention is applied) according to the present invention, and FIG. 2 is a cross-sectional view of a main part of the axial gap type rotating electrical machine. is there.

  As shown in the figure, an axial gap type rotating electrical machine 1 (hereinafter abbreviated as a rotating electrical machine 1) is interposed between a rotor 2 having a rotating shaft 10 as a center and rotor bodies 12A and 12B described later of the rotor 2. The stator 4 is opposed to the rotor bodies 12A and 12B at a predetermined interval in the axial direction of the rotary shaft 10, and a pair of cases 6.

  In the following description, the direction parallel to the rotation shaft 10 is referred to as “axial direction”, the direction orthogonal to the rotation shaft 10 is referred to as “radial direction”, and the rotation direction of the rotation shaft 10 (rotor 2) is referred to as “circumferential direction”. .

  The rotor 2 includes a pair of disk-shaped rotor main bodies 12A and 12B arranged to face each other at a predetermined interval, and a rotating shaft 10 penetrating through the centers of the rotor main bodies 12A and 12B. Each rotor main body 12A, 12B is fixed to a rotating shaft 10, and the rotating shaft 10 is supported by the case 6 via a bearing 7 described later.

  Each of the rotor bodies 12A and 12B includes a rotor disk 14 also serving as a back yoke, and a plurality of permanent magnets 16 fixed to the rotor disk 14 in a state of being arranged in the circumferential direction. Each permanent magnet 16 is a plate-like magnet, and is fixed to a surface of the rotor disk 14 that faces the stator 4. The permanent magnet 16 of the rotor body 12A on the one side and the permanent magnet 16 of the rotor body 12B on the other side are mirror-symmetrical. In this example, for the purpose of reducing cogging torque, etc., it is slightly rhombus in plan view. It has a close shape. Note that the number and arrangement of the permanent magnets 16 in the rotor main bodies 12A and 12B are the same.

  The stator 4 is disposed between the rotor bodies 12 </ b> A and 12 </ b> B of the rotor 2. As shown in FIG. 1, the stator 4 includes a stator body 20, an inner cylindrical member 24 that is disposed on the inner side (described later stator core assembly 30) and reinforces the stator body 20 from the inner side, and the stator body 20 (described later stator core). An outer cylindrical member 26 which is disposed outside the assembly 30) and reinforces the stator body 20 (described later stator core assembly 30) from the outside, and a pair of support members 22 which support the stator body 20 from both sides in the axial direction. Including.

  The stator body 20 has a substantially annular (donut type) shape with a through hole 20a penetrating in the axial direction as a center. The stator main body 20 includes a stator core assembly 30 having a plurality of stator cores arranged in the circumferential direction, a coil 32 attached to each stator core, and a lid member 34 fixed to the stator core assembly 30.

  As shown in FIGS. 5 to 7, the stator core assembly 30 includes a plurality of stator cores 40 arranged at equal intervals in the circumferential direction, and a housing 42 (corresponding to a holding member of the present invention) that holds the stator cores 40. ing.

  The stator core 40 has a block-like structure in which a plurality of rectangular electromagnetic steel plates 40a having different sizes are stacked in the radial direction. Each of the electromagnetic steel sheets 40a has different dimensions in the width direction perpendicular to the radial direction, and the electromagnetic steel sheet 40a positioned on the radially outer side has a larger dimension in the width direction than the electromagnetic steel sheet 40a positioned on the radially inner side. Is set. Thereby, the stator core 40 is formed in a trapezoidal shape in plan view as shown in FIG. 2 and 7, the electromagnetic steel plate 40a is omitted and only the outline of the stator core 40 is shown.

  Each stator core 40 is integrally held by the housing 42. That is, the housing 42 is formed of a resin material having electrical insulation. In this example, the stator core assembly 30 is integrally formed by insert molding in which each stator core 40 is a metal part and the housing 42 is a resin part. . Thereby, the stator cores 40 are integrally held by the housing 42. The resin material forming the housing 42 includes fillers such as glass fiber, carbon fiber, whisker, talc, and the like, so that the linear expansion coefficient of the housing 42 is substantially equal to the linear expansion coefficient of the stator core 40. The housing 42 is formed so as to be equivalent.

  The housing 42 has a bobbin portion 43a formed on the outer peripheral surface thereof so as to surround the stator core 40 in a state where both ends (both ends in the axial direction) of the stator core 40 are exposed, and a space is formed inside each bobbin portion 43a. The inner cylinder part 43b formed at intervals, the outer cylinder part 43c formed at intervals outside the bobbin parts 43a, and one end of the bobbin part 43a, the inner cylinder part 43b and the outer cylinder part 43c (The lower end portion in FIG. 7), and has an end surface portion 43d that forms a groove portion 46 between the bobbin portion 43a, the inner tube portion 43b, and the outer tube portion 43c. The bobbin portion 43a and the inner tube portion 43b, the outer cylinder part 43c, and the end surface part 43d are integrally molded by the resin material.

  The coil 32 is a concentrated winding coil, and is attached (wound) to the stator core 40 from the outside of the bobbin portion 43a as shown in FIGS. Specifically, the coil 32 is an edgewise coil, and a rectangular copper wire having a rectangular cross section is wound along the stator core 40 (bobbin portion 43a) with its short side surface as an inner diameter surface. For the sake of convenience, in FIG. 3, the crossover portion connecting adjacent coils 32 is omitted.

  The lid member 34 is a disk-shaped member having an outer diameter equivalent to that of the housing 42 and having a through hole 34 a having the same diameter as the inner diameter of the inner cylindrical portion 43 b of the housing 42. And the same resin material. The lid member 34 is fixed to an end portion in the axial direction of the housing 42, specifically, an end portion opposite to the end face portion 43 d side so as to close the groove portion 46. Thereby, a closed space 21 in which the coil 32 is accommodated is formed in the stator body 20. More specifically, a plurality of window portions 34b having a shape corresponding to the stator core 40 are formed around a through hole 34a at the center of the lid member 34. On the other hand, as shown in FIG. 5, the end portion (axial end portion) of each stator core 40 protrudes outward in the axial direction from the end portion of the housing 42, and the end portion of each stator core 40 fits into the window portion 34b. The lid member 34 is fixed to the housing 42 by ultrasonic vibration welding in a state where the lid member 34 is overlapped with the end portion of the housing 42 so as to match.

  The pair of support members 22, the inner cylinder member 24, and the outer cylinder member 26 are assembled to the stator body 20 configured as described above. Specifically, the inner cylinder member 24 is fitted inside the inner circumferential surface of the stator body 20, that is, the inside of the through hole 20 a, while the outer cylinder member 26 is fitted on the outer circumferential face of the stator body 20, The support members 22 are fixed to the inner cylinder member 24 and the outer cylinder member 26 in a state where the support members 22 are superposed on the stator main body 20.

  Each support member 22 has the same configuration, and is a disk-shaped member that is formed of a nonmagnetic material (austenitic stainless steel, aluminum, etc.) and has an outer diameter equivalent to that of the outer cylindrical member 26. It is. As shown in FIG. 1, a through hole 22 a having the same diameter as the inner cylinder member 24 is formed at the center of the support member 22, and the periphery of the through hole 22 a corresponds to the stator core 40 of the stator body 20. A plurality of window portions 22b having a shape are formed. Then, as shown in FIG. 2, in a state where each support member 22 is superimposed on the end of the stator body 20 from both sides in the axial direction so that the end of each stator core 40 fits into the window 22 b. The support members 22 are fixed to the end surfaces of the inner cylinder member 24 and the outer cylinder member 26 with bolts (disk screws) B1, respectively. Thereby, the whole stator main body 20 is covered with the inner cylinder member 24, the outer cylinder member 26, and the support member 22 in a state where the end surfaces of the stator cores 40 face both axial sides.

  As shown in FIG. 3, a coolant introduction port IP and a lead-out port OP are provided at positions on the outer cylinder member 26 opposite to each other in the radial direction. On the other hand, coolant such as oil can be supplied and discharged. That is, in this rotating electrical machine 1, the coolant is led out from the lead-out port OP through the opening 45 b of the housing 42 while the coolant is introduced into the closed space 21 through the opening 45 a of the housing 42 from the introduction port IP. Thus, the coolant is circulated with respect to the closed space 21, thereby cooling the coil 32. In this example, the openings 45a and 45b and the ports IP and OP of the housing 42 correspond to the coolant supply / discharge portion of the present invention.

  As shown in FIG. 1, a pair of the cases 6 are provided on both sides in the axial direction of the rotating electrical machine 1. Each case 6 has the same structure, and has a bottomed cylindrical shape including a peripheral wall portion 50 having a thickness equivalent to that of the outer cylinder member 26 and an end surface portion 52 that closes one side thereof. . A shaft hole 50 a is formed at the center of each end surface portion 52.

  Each case 6 is assembled to the stator 4 from both sides in the axial direction in a state in which the rotor main bodies 12A and 12B are included inside the peripheral wall portion 50. Specifically, as shown in FIG. 2, the rotor body 12 </ b> A, 12 </ b> B is positioned on both sides in the axial direction of the stator body 20, and the rotor 2 is fixed to the stator 4 so that the rotating shaft 10 passes through the through hole 20 a of the stator body 20. In this state, each case 6 is in contact with the stator 4 from both sides in the axial direction so that both ends of the rotating shaft 10 are led out through the shaft hole 50a. As shown in FIGS. 2 and 4, in the state where the outer cylindrical member 26 and the support member 22 of the stator 4 are sandwiched from both sides in the axial direction by the peripheral wall portion 50 of each case 6, the peripheral wall portion 50 is connected to the outer cylindrical member 26. Are fixed with bolts B2. Thereby, each case 6 is each assembled | attached to the stator 4 in the state which includes the said rotor main bodies 12A and 12B. In addition, the bearing 7 (refer FIG. 1) is hold | maintained at the end surface part 52 of each case 6, The said rotating shaft 10 is inserted in the bearing 7 of each case 6, and is prevented from coming off. Thereby, the rotor 2 is rotatably supported by the case 6.

  The position of the bolt B2 that fixes each case 6 to the outer cylinder member 26 and the position of the bolt B1 that fixes each support member 22 to the outer cylinder member 26 in the stator 4 are offset from each other in the circumferential direction. Both the case 6 and the support member 22 can be fastened to the outer cylinder member 26 with bolts B1 and B2 along the axial direction.

  In the stator 4 of the rotating electrical machine 1 as described above, the stator core assembly 30 in which a plurality of stator cores 40 and the housing 42 are integrally formed by insert molding is provided, and the coils 32 are connected to the stator core from the outside of each bobbin portion 43a of the housing 42. 40 (wound). According to such a configuration, since the plurality of stator cores 40 are integrally held by the housing 42, the structural stability is good and the productivity of the rotating electrical machine 1 is improved. Moreover, since the coils 32 are attached to the respective stator cores 40 from the outside of the bobbin portion 43a, the heat dissipation performance of the coils 32 is also ensured. Therefore, according to the rotary electric machine 1, it is possible to improve the cooling performance of the stator 4 while contributing to the productivity improvement of the axial gap type rotary electric machine.

  In particular, in the stator 4, the closed space 21 in which the coil 32 is accommodated is formed inside the stator 4, and the cooling liquid is circulated through the closed space 21, so that the coil 32 can be effectively cooled. it can. In addition, the stator core 40 and the housing 42 are integrally formed by insert molding, and the bobbin portion 43a and the stator core 40 are in close contact with each other without gaps. The heat is efficiently radiated to the coolant through the bobbin portion 43a and the coil 32. Therefore, according to the stator 4, it is possible to effectively suppress a decrease in operating efficiency of the rotating electrical machine 1 due to the heat generation of the stator 4.

  Further, according to the stator 4, since the closed space 21 is formed by fixing the lid member 34 to the stator core assembly 30 so as to close the groove portion 46, the leakage of the coolant can be prevented well. There is also an advantage of being able to. That is, according to the above configuration, there is no portion where liquid leakage occurs other than the contact surface between the housing 42 and the lid member 34, but the housing 42 and the lid member 34 are ultrasonic vibration welded on the contact surface. A high degree of liquid tightness is secured by being fixed by. Therefore, according to the stator 4, it is possible to highly prevent the leakage of the coolant.

  Further, according to the stator 4, since the stator core 40 and the housing 42 are integrally formed, the electromagnetic steel plates 40a constituting the stator core 40 are strongly coupled by a so-called anchor effect. Therefore, there is also an advantage that the structural stability of the stator core 40 can be secured by satisfactorily coupling the electromagnetic steel sheets 40a without using fixing means such as an adhesive or caulking.

  Further, according to the stator 4, since the housing 42 is formed so that the linear expansion coefficient of the stator core 40 and the linear expansion coefficient of the housing 42 holding the stator core 40 are substantially equal, the stator core 40 and the housing 42 The balance of thermal deformation is maintained. Therefore, the housing 42 is cracked due to the difference in thermal deformation amount to induce liquid leakage, or a gap is generated between the stator core 40 and the housing 42 (bobbin portion 43a), causing the stator core 40 to be displaced. Can be prevented from occurring.

  Further, according to the stator 4 including the stator core assembly 30, since the stator core 40 and the housing 42 are integrated by insert molding when the stator core assembly 30 is manufactured, for example, manufacture of the stator core (integration of electromagnetic steel sheets). Compared with the case where the operations such as the manufacture of the bobbin and the assembly of the bobbin to the stator core are individually performed, the manufacturing man-hours of the stator 4 can be greatly reduced. Therefore, there is also an advantage that the productivity of the stator 4 and thus the productivity of the rotating electrical machine 1 can be improved.

  As mentioned above, although embodiment of the rotary electric machine 1 (rotary electric machine 1 to which the stator 4 of this invention was applied) of this invention was described, the said rotary electric machine 1 and the stator 4 are illustrations of preferable embodiment of this invention. The specific configuration can be appropriately changed without departing from the gist of the present invention.

  For example, in the above embodiment, the housing 42 and the lid member 34 of the stator core assembly 30 are fixed to each other by ultrasonic vibration welding, but may be fixed by other fixing methods. For example, a structure in which a seal member is interposed between the housing 42 and the lid member 34 and both are fixed with bolts may be used.

  In the above embodiment, the inner cylinder member 24 and the outer cylinder member 26 are provided separately from the stator core assembly 30, but may be provided integrally with the stator core assembly 30. That is, the stator core assembly 30 may be integrally molded by insert molding in which the inner cylinder member 24, the outer cylinder member 26 and the stator core 40 are metal parts and the housing 42 is a resin part. According to this configuration, it is possible to further increase the productivity of the stator 4 and, consequently, the productivity of the rotating electrical machine 1.

  In the above embodiment, an example in which the present invention is applied to a two-rotor, one-stator type rotating electrical machine 1 in which two rotor bodies 12A, 12B are provided on both sides of one stator 4 has been described. The invention can also be applied to a one-rotor, one-stator type rotating electric machine, and a one-rotor, two-stator type rotating electric machine.

DESCRIPTION OF SYMBOLS 1 Axial gap type rotary electric machine 2 Rotor 4 Stator 10 Rotating shaft 12A, 12B Rotor main body 20 Stator main body 30 Stator core assembly 32 Coil 34 Lid member 42 Housing (holding member)
43a Bobbin part 43b Inner cylinder part 43c Outer cylinder part 43d End surface part

Claims (6)

A stator of an axial gap type rotating electrical machine,
A plurality of stator cores arranged in the circumferential direction around the rotation axis, a holding member that is formed of an electrically insulating resin material and integrally holds the plurality of stator cores, and a coil that is attached to each of the plurality of stator cores. Including
The holding member includes an inner cylinder portion positioned inside the plurality of stator cores arranged in the circumferential direction, an outer cylinder portion positioned outside the plurality of stator cores, and an end portion of the stator core in the axial direction of the rotating shaft. Is connected to the bobbin portion that is formed on the outer peripheral surface of the stator core and holds the stator core, and one end of the bobbin portion, the inner cylindrical portion, and the outer cylindrical portion in the axial direction. Including an end surface portion that forms a groove portion between the bobbin portion, the inner cylindrical portion, and the outer cylindrical portion, and is integrally molded with the plurality of stator cores,
The coil is attached to the stator core from the outside of the bobbin portion ,
The stator further includes a lid member that forms a closed space in which the coil is accommodated together with the holding member by being fixed to the holding member so as to close the groove.
The stator, wherein the holding member is provided with a coolant supply / discharge portion capable of supplying and discharging coolant in the closed space . The stator according to claim 1 ,
The stator, wherein the lid member is ultrasonically welded to the holding member. The stator according to claim 1 ,
An inner cylinder member that reinforces the holding member provided in contact with the inner peripheral surface of the inner cylinder portion, and a holding member that is provided in contact with the outer peripheral surface of the outer cylinder portion. An outer cylinder member that reinforces the member. The stator according to claim 3 ,
The inner cylinder member and the outer cylinder member are formed of a metal material,
The stator, wherein the inner cylinder member, the outer cylinder member, the plurality of stator cores, and the holding member are integrally formed. The stator according to any one of claims 1 to 4 ,
The stator having a linear expansion coefficient equivalent to the stator core and the holding member. A rotor comprising a rotating shaft and a rotor body rotating with the rotating shaft;
An axial gap type comprising the stator according to any one of claims 1 to 5 disposed at a predetermined interval in the axial direction of the rotating shaft with respect to the rotor body. Rotating electric machine.

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