JP2010246171A - Axial gap type dynamo-electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly efficient and compact axial gap type dynamo-electric machine simultaneously meeting miniaturization of axial gap type dynamo-electric machines and high strength of core retention. <P>SOLUTION: In the axial gap type dynamo-electric machine 101, a stator 2 is sandwiched with a prescribed gap for oppositely disposing rotors 3 along an axial direction of a rotor shaft 1. The stator 2 includes: a plurality of rod-like stator cores 22 disposed along a circumferential direction with the axis of the rotor shaft 1 as the center axis while directing its axial direction toward the axial direction of the rotor shaft 1; a disk-like core retention member 21 including a plurality of holes or grooves in nearly the same shape as the sectional shape of the stator core 22 along a circumferential direction with the axis of the rotor shaft 1 as the center axis; and a coil 23 wound around the stator core 21. The stator core 22 is inserted into the holes or grooves of the core retention member 21, and is fixed and held near the center in the axial direction. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an axial gap type rotating electrical machine (axial gap type motor) having a gap in the axial direction.

In recent years, the necessity of energy saving has been regarded as important in industrial equipment, home appliances, automobile parts, and the like. More than half of the amount of power used in the country is consumed by driving a rotating electrical machine (motor). Therefore, the rotating electrical machine is required to achieve both high efficiency and low cost.
The basic structure of a permanent magnet synchronous rotary electric machine is composed of a soft magnetic material, a coil, and a permanent magnet. And the loss of this rotary electric machine is divided roughly into an iron loss and a copper loss. The iron loss is determined by the characteristics of the soft magnetic material. The copper loss is determined by the resistance value of the coil, that is, the space factor, and the loss can be reduced as the winding is made more compact. The method of increasing the efficiency is achieved by designing the shape and dimensions of the rotating electrical machine that can reduce these losses. However, changing the material characteristics can also contribute to higher efficiency.

  The axial gap type rotating electrical machine is considered to be one of the methods for reducing the loss in a flat rotating electrical machine structure. In a stator used in a flat radial type rotary electric machine that is thin in the axial direction of the rotor shaft, a structure is often employed in which a winding is applied to an iron core formed by punching electromagnetic steel sheets and stacking them in the axial direction of the rotor shaft. . However, since the ratio of the coil end portion of the coil to the iron core portion effective for torque output facing the rotor is increased, the coil resistance value is increased and the copper loss is increased. Therefore, in a flat rotating electrical machine structure, the axial type in which the facing surface of the iron core portion that contributes to torque output to the rotor is arranged in the axial direction of the rotor shaft is effective in reducing copper loss. In addition, it is desirable to use a material with high magnetic permeability and low iron loss in order to reduce iron loss.

  As a basic structure of an axial gap type rotating electrical machine, there is a structure as shown in Patent Document 1. Since this structure has a tooth portion and a yoke portion, only one side in the axial direction of the rotor shaft has a facing surface that contributes to torque output. Moreover, since it is the structure which flows a magnetic flux from a teeth part to a yoke part, it is necessary to use the soft magnetic material which considered that a magnetic flux flows three-dimensionally. In order to satisfy these requirements, it is necessary to use materials having magnetic properties that are three-dimensionally isotropic, such as powder magnetic cores. Compared with the low magnetic permeability and the large iron loss, there is a problem that it is difficult to reduce the size in obtaining a high-output rotating electrical machine.

  As a method for solving the above problem, a rotating electrical machine technique described in Patent Document 2 has been proposed. In the rotating electrical machine described in Patent Document 2, an example is shown in which the stator is provided with two opposing surfaces to the rotor in the axial direction of the rotor shaft, and the iron core is formed of a silicon steel plate. A method is disclosed in which a stator is formed by winding around an iron core and then molding and fixing with a resin member.

JP 2005-287212 A JP 2007-274850 A

  However, methods of mold-fixing with engineering plastics such as thermosetting resins have been conventionally used in rotating electric machines, but all are limited to rotating electric machines of small capacity machines. In mold fixing, it has been difficult to use a rotating electrical machine that requires a large torque or a high rotational speed in terms of strength.

  The present invention solves the above-described conventional problems, and provides a small-sized axial gap type rotating electrical machine that satisfies both the downsizing of the axial gap type rotating electrical machine and the high strength of the iron core holding at the same time, and is highly efficient. For the purpose.

  In order to solve the above-described problem, the axial gap type rotating electrical machine according to the first aspect of the present invention has a stator whose axial direction is along the circumferential direction about the axis of the rotor shaft as a central axis and in the axial direction of the rotor shaft. A plurality of rod-shaped stator cores that are arranged facing each other, and a plurality of holes or grooves having substantially the same shape as the cross-sectional shape of the stator core are provided along the circumferential direction about the axis of the rotor shaft. A disk-shaped stator core holding member and a coil wound around the stator core, and the stator core is inserted into the hole or groove of the stator core holding member, and the axial direction of the stator core It is characterized by being fixedly held near the center.

  According to the first invention, the stator core can be press-fitted into the disk slot portion of the stator core holding member or can be shrink-fitted and fixed, which is stronger than the conventional method of fixing the stator core using a mold. Can be fixed high.

  According to a second aspect of the present invention, the stator core holding member is made of a conductive high-strength metal material, has a radial notch that reaches the hole or groove from the outer peripheral edge, and the notch has a circular shape. The outer peripheral edge partitioned in the circumferential direction forms a gap between the first outer peripheral edge portion that contacts the inner peripheral surface of the cylindrical housing that houses the stator and the rotor, and the inner peripheral surface of the housing. It is characterized by being comprised from the outer periphery part.

  According to the second invention, the stator core holding member can be press-fitted and fixed to, for example, a cylindrical housing, and when the stator core holding member is made of a conductive material such as metal, the stator core holding It has a notch in the radial direction reaching the hole or groove from the outer peripheral edge of the member, and the second outer peripheral edge portion of the outer peripheral edge of the stator core holding member does not contact the housing, so that it occurs in the stator core holding member A part of the eddy current path is cut off, and iron loss can be reduced.

  Furthermore, the third invention is characterized in that, in addition to the configuration of the first invention, two or more of the stators are arranged in the axial direction of the rotor shaft.

  According to the third aspect of the invention, the stator core holding member can be fixed firmly and with high precision to the housing, and therefore, a plurality of the stators are arranged in the axial direction of the rotor shaft in one rotating electrical machine. It becomes possible to do.

  According to the present invention, it is possible to provide a small-sized axial gap type rotating electrical machine that satisfies both the downsizing of the axial gap type rotating electrical machine and the high strength of holding the iron core at the same time, and is highly efficient.

It is a fragmentary sectional perspective view of the rotary electric machine which concerns on 1st Embodiment. It is the disassembled perspective view which expand | deployed the component of the rotary electric machine which concerns on 1st Embodiment in the rotor axial direction. FIG. 3 is a structural diagram of an iron core holding member constituting the stator of the rotating electrical machine according to the first embodiment, wherein (a) is a perspective view and (b) is a plan view. It is a figure explaining the manufacturing method of the stator core used for the stator of the type | mold rotary electric machine of 1st Embodiment, a shape, etc., (a) is the shape of the wound iron core of the electromagnetic steel plate before cutting out a stator core. (B) is a perspective view of a stator core formed by cutting out a wound iron core, (c) is a perspective view of a stator core formed by compacting magnetic powder, and (d) is a magnetic powder. The perspective view of the stator iron core which carried out the powder compaction | molding by attaching the corner | angular radius to the corner | angular part, (e) is a perspective view of the stator core of a substantially rectangular cross-sectional shape. The perspective view after fixing a stator core to the iron core holding member which comprises a stator. It is explanatory drawing of the method of attaching a coil to a stator core. It is a whole perspective view of the stator of the rotary electric machine which concerns on 1st Embodiment. It is explanatory drawing which shows the contact relationship at the time of fixation with the outer periphery of the stator and housing inner peripheral surface in the rotary electric machine which concerns on 1st Embodiment. It is a perspective view of one rotor of the rotary electric machine which concerns on 1st Embodiment. It is a fragmentary sectional perspective view of the rotary electric machine which concerns on 3rd Embodiment. It is the disassembled perspective view which expand | deployed the component of the rotary electric machine which concerns on 3rd Embodiment in the rotor axial direction. It is explanatory drawing of the magnet holding method of the intermediate rotor of the rotary electric machine which concerns on 3rd Embodiment, (a) is a disassembled perspective view, (b) is an assembly perspective view. It is a figure explaining the 1st modification of the magnet holding method of the intermediate rotor of the rotary electric machine which concerns on 3rd Embodiment, (a) is an expansion | deployment perspective view, (b) is an assembly perspective view. It is a figure explaining the 2nd modification of the magnet holding | maintenance method of the intermediate rotor of the rotary electric machine which concerns on 3rd Embodiment, (a) is a partial cross-sectional perspective view of an intermediate rotor, and the perspective view of the permanent magnet, (b) is a figure explaining the contact relationship at the time of the fixing of the rotor disk of A part and B part and permanent magnet in (a).

Hereinafter, a first embodiment of the present invention will be described in detail with reference to FIGS.
<< First Embodiment >>
FIG. 1 is a partial cross-sectional perspective view of the rotating electrical machine according to the first embodiment, and FIG. 2 is an exploded perspective view in which components of the rotating electrical machine according to the first embodiment are developed in the rotor axial direction. FIG. 3 is a structural diagram of an iron core holding member constituting the stator of the rotating electrical machine according to the first embodiment, wherein (a) is a perspective view and (b) is a plan view.
As shown in FIG. 1, this axial gap type rotating electrical machine 101 (hereinafter simply referred to as “rotating electrical machine 101”) has a predetermined gap (gap) between both sides of the stator 2 and the axial direction of the rotor shaft 1 of the stator 2. ) And a pair of rotors 3A, 3B arranged opposite to each other, which are housed in the housing 4, with both axially outer side surfaces (upper and lower outer surfaces in FIG. 1) of the rotor shaft 1 at the center. It is covered with a disk-shaped cover 8 having a shaft hole 8a (see FIG. 2).
Incidentally, the rotating electrical machine 101 is a three-phase permanent magnet synchronous motor.

(Rotor)
Each rotor 3A, 3B also serves as a yoke (back yoke) having a rotor shaft hole 32a (see FIG. 2) in the center. For example, permanent magnets 31 are provided on one side of rotor disks 32A, 32B made of electromagnetic steel plates or the like. The rotor shaft 1 is periodically bonded and fixed in the circumferential direction with the axis of the rotor shaft 1 as the central axis, and is coaxially fixed to the rotor shaft 1 that outputs a rotational driving force by a key (not shown) or the like.
As shown in FIG. 2, the number of permanent magnets 31 bonded to the rotor 3 </ b> A and the rotor 3 </ b> B is six, for example, and is not necessarily limited to the stator core 22 and the core holding member (stator core holding member) 21 of the stator 2. The number of pole members composed of a pair of coils 23 sandwiching the core, for example, nine, need not be the same, and the planar shape of the permanent magnet 31 does not need to match the sectional shape of the stator core 22.
However, when the permanent magnet 31 of the rotor 3A and the permanent magnet 31 of the rotor 3B are viewed from either the upper side or the lower side of the rotor shaft 1 in FIG. It is necessary to be arranged in.
The rotor 3A in FIG. 2 is a perspective view seen from the lower surface side, and the rotor 3B in FIG. 2 is a perspective view seen from the upper surface side, and the straight lines constituting the outer shape of both ends in the circumferential direction of the permanent magnet 31 are rotor shafts. The angle that intersects the tangent of a circle centered on one axis is different.
For example, FIG. 2 shows a case where the planar shape of the permanent magnet 31 has a substantially rhombus shape. This is an example of a shape for reducing torque pulsation and cogging torque.
For the rotors 3A and 3B, it is considered that a cage structure without using a permanent magnet, a magnetic disk, a conductive disk, a rotor whose reluctance varies depending on the circumferential position, and the like can be used.

(Stator)
As shown in FIG. 1, the stator 2 has a rod-shaped stator iron core 22 that constitutes a pole member, the axial direction of which is directed to the axial direction of the rotor shaft 1, and the axial direction of the rotor shaft 1 is the circumferential axis. A coil 23 is wound around the stator core 22.

As shown in FIG. 2, the stator 2 has a bearing holding member (bearing holding member) 25 on the radially inner side. The bearing holding member 25 is provided with bearing holding holes 25a and 25a (see FIG. 3) that are bottomed cylindrical cavities on both sides in the axial direction of the rotor shaft 1, and the ball bearings 5 and 5 are housed therein and fixed. To do. A substantially disk-shaped iron core holding member 21 (see FIGS. 1 and 3) extends radially outward from the axial center of the rotor shaft 1 on the outer peripheral surface of the bearing holding member 25 to the radially outer side. Yes.
The rotor shaft 1 passes through the bottomed portion of the bearing holding hole 25a, and a rotor shaft hole 25b (see FIG. 3) that secures a gap between the rotor shaft 1 and the outer peripheral surface thereof is formed.
Here, both the core holding member 21 and the bearing holding member 25 are made of high-strength engineering plastic and are integrally molded.

As shown in FIG. 3, the iron core holding member 21 is connected to the annular disk base portion region 21 d extending radially outward from the outer peripheral surface of the bearing holding member 25, and to the radially outer side thereof in the radial outer periphery side. The substantially fan-shaped iron core holding regions 21a and 21b are periodically arranged in the circumferential direction, for example, 21a, 21b, 21b, 21a, 21b, 21b,.
The core holding region 21a has, on its radially outer side, an edge (first outer peripheral edge) 21a ₁ extending on both sides in the circumferential direction, and the core holding region 21b has its radially outer side. the edges extending the member to both sides in the circumferential direction (the second outer peripheral edge portion) has 21b _1.

The distance from the axis (rotation center axis) of the rotor shaft 1 at the radially outer end of the edge 21a ₁ is set slightly larger than that at the radially outer end of the edge 21b ₁ . Therefore, when the stator 2 is assembled in the housing 4, the outer peripheral surface of the edge portion 21 a ₁ and the inner peripheral surface 4 a (see FIG. 9) of the housing 4 abut, and the outer peripheral surface of the edge portion 21 b ₁ and the inner peripheral surface of the housing 4. A gap is formed between the surface 4a.

Further, between the core holding regions 21a and 21b adjacent in the circumferential direction, for example, a substantially fan-shaped hole or groove 21c ₁ having substantially the same shape as the cross-sectional shape of the stator core 22 is formed in the circumferential direction. Similarly, between the adjacent core holding regions 21b and 21b, for example, a substantially fan-shaped hole or groove 21c ₂ having substantially the same cross-sectional shape as that of the stator core 22 is formed.

Furthermore, the circumferential direction between the circumferential end of the edge 21a ₁ adjacent to the circumferential direction and the circumferential end of the edge 21b _{1 and} the circumferential end of the circumferential edge 21b ₁ adjacent to the circumferential direction and the edge 21b ₁ A notch 21e is formed between the ends. Between the adjacent iron core holding regions 21a and 21b and between the adjacent iron core holding regions 21b and 21b, the edges are radially outward. Is cut off.

The substantially fan-shaped holes or grooves 21c ₁ and 21c ₂ have the same planar shape, and correspond to the number of pole members of the stator along the circumferential direction with the axis of the rotor shaft 1 as the central axis. Periodically, for example, 21c ₁ , 21c ₁ , 21c ₂ , 21c ₁ , 21c ₁ , 21c ₂ are formed in this order.
It should be noted that the corners of the periphery of the holes or grooves 21c ₁ and 21c ₂ are preferably rounded to avoid stress concentration.
3B, the stator core 22 is inserted and fixed in the edges 21a ₁ and 21b ₁ and the holes or grooves 21c ₁ and 21c ₂ of the core holding member 21, and then the coil 23 is attached to the stator core 22. In order to show the positional relationship of the outer shape of the coil 23 in the inserted and fixed state, the position of the outer shape of the coil 23 is indicated by a virtual line.

(Stator core)
Next, the configuration of the stator core 22 will be described with reference to FIG. As a constituent material of the stator core 22, a soft magnetic material such as a silicon steel plate, an amorphous material, a dust core, permalloy, or permendur can be used. When it is made of a thin plate such as a silicon steel plate or permalloy, the wound core 22 'as shown in FIG. 4 (a) is annealed to remove the strain, and fixed with a resin, an adhesive, or the like. The stator core 22A (FIGS. 1 and 2 and FIGS. 5, 7, and 9 to be described later) are typically fixed by cutting them into a predetermined shape as shown in FIG. And a core iron core 22).
Moreover, when it comprises from foil strips, such as an amorphous, the iron core which has a substantially fan-shaped cross-sectional shape can be obtained with the same method.
In addition, when it comprises from foil strips, such as amorphous, it does not cut out from the shape of wound core 22 'shown to (a) of Drawing 4, but forms foil strips, such as amorphous, directly so that a section may become a fan shape. You can also

  The shape of the stator core 22B composed of a powder magnetic core obtained by compacting a magnetic powder coated with a resin can be directly molded as shown in FIG. 4 (c). Further, it is possible to provide an anisotropy at the time of molding so that the axial direction indicated by the arrow has a good magnetic property. When the stator core 22 is formed of a powder magnetic core, any shape of the axial cross section can be formed. Therefore, the corners of the stator core 22C shown in FIG. It can be formed into a certain shape.

When the stator core 22 is formed of a plate material, a press lamination method can be considered as another method different from the above. In this case, the stator core 22D can be manufactured by such a method as long as it has a substantially rectangular cross-sectional shape as shown in FIG.
The cross-sectional shape of the stator core 22 is not limited to the above-described substantially fan shape or rectangle, but may be a circle or an ellipse.

  Next, the assembly method of the stator 2 and the assembly method of the rotating electrical machine 101 will be described with reference to FIGS. 2 and 3 as appropriate with reference to FIGS.

(Attaching the stator core to the core holding member)
FIG. 5 is a perspective view after the stator core is fixed to the core holding member constituting the stator.
As shown in FIG. 5, first, the stator core 22 is press-fitted into fan-shaped holes or grooves 21c ₁ and 21c ₂ (see FIG. 3) formed in the core holding member 21 and fixed. For example, the iron core holding member 21 is placed on a jig base having a predetermined number of receiving holes of a depth that allows the stator iron core 22 to be inserted from one side into the holes or grooves 21c ₁ and 21c ₂ to protrude to the opposite side. By fixing and press-fitting the stator cores 22 one by one in order from one side, the axially central portion of the stator core 22 is easily fixed and held by the core holding member 21. Here, by forming the notch portion 21e, the core holding regions 21a and 21b can escape in the circumferential direction during press-fitting, and cracks can be prevented from entering the holes or grooves 21c ₁ and 21c ₂ . Further, since the corners of the periphery of the holes or grooves 21c ₁ and 21c ₂ are rounded as described above, it is possible to prevent the corners from cracking when the stator core 22 is press-fitted.

(Mounting the coil to the stator core)
FIG. 6 is an explanatory view of a method of attaching a coil to the stator core, and FIG. 7 is an overall perspective view of the stator of the rotating electrical machine according to the first embodiment.
The coils 23 and 23 are connected by a winding intermediate portion 23a and configured as a single pole component coil. The coil is manufactured by a method of assembling a coil wound around an insulating bobbin, a method of directly winding the stator iron core 22, or the like. At this time, since the connection of the coil winding intermediate part 23a is a complicated manufacturing process in the subsequent process, the two coils 23 and 23 arranged in the axial direction of the stator core 22 are continuously wound. It is desirable to have a winding intermediate portion 23a that can be assembled from both sides in the axial direction. Further, in order to rationalize the wiring, there is a method in which the coil 23 is connected to the winding ends 23b and 23b and the coils of the same phase as a three-phase rotating electric machine are continuously wound and assembled. Conceivable. By such a procedure, the stator 2 of the rotating electrical machine 101 can be obtained.

A specific example will be described. As shown in FIG. 6, two insulating bobbins (not shown) having the same cross-sectional shape of the stator core 22 as if two sets of coils 23 were connected by a winding intermediate portion 23a. Are used to form coils 23 and 23 for one pole member. Then, as shown in FIG. 7, the coils 23 and 23 are fitted into one stator core 22 from both sides of the core holding member 21. At this time, the winding direction is the same as that of the rotor shaft 1 in the axial direction. Thereafter, resin or the like is impregnated into the coil 23 and fixed to the stator core 22.
Incidentally, the winding ends 23b and 23b may be connected to the coil 23 for other pole components in the same phase.
The winding intermediate portion 23a and the winding end 23b are bonded to the iron core holding regions 21a and 21b of the stator 2 with resin or the like and fixed so as not to contact the rotors 3A and 3B.

(Attaching the stator to the housing)
Next, a method for fixing the stator 2 to the housing 4 will be described with reference to FIG.
FIG. 8 is an explanatory diagram illustrating a relationship between the outer peripheral edge of the stator and the inner peripheral surface of the housing in the mold rotating electric machine according to the first embodiment when being fixed.
As shown in FIG. 8, the stator 2 and the housing 4 can be fixed by press-fitting the stator 2 into the cylindrical housing 4. As described above, only the edge portion of the fan-shaped iron core holding region 21 a of the iron core holding member 21 abuts on the inner peripheral surface 4 a of the housing 4 and is fixed.
Although not shown in FIG. 8, the ball bearing 5 is already inserted and fixed in the bearing hole 25b on the upper surface side in FIG.

(Assembly of stator and rotor)
FIG. 9 is a perspective view of one rotor of the rotating electrical machine according to the first embodiment.
A procedure for incorporating the rotors 3A and 3B into the stator 2 will be described with reference to FIGS.
First, as shown in FIG. 9, the rotor shaft 1 is inserted into the rotor shaft hole 32a of the rotor 3B from one side in the axial direction, and is fixed integrally with the rotor shaft 1 with a key or the like. Next, in FIG. 9, the ball bearing 5 is fitted to the rotor shaft 1 on the upper surface side of the rotor 3 </ b> B. Then, the rotor shaft 1 is inserted into the rotor shaft hole 25b of the stator 2 already fixed to the housing 4 from the lower side in FIG. 2, and the ball bearing 5 fitted to the rotor shaft 1 is placed on the lower side of the stator 2. It fits in the bearing holding hole 25a. At this time, the rotor disk 32 </ b> B positioned and held on the lower end side of the bearing holding member 25 has a positional relationship such that a gap dimension designed in advance is formed on the opposing surfaces of the permanent magnet 31 and the stator core 22. ing.

  The rotor shaft 1 protrudes upward in FIG. On this upper side, the ball bearing 5 is fitted into the bearing holding hole 25a on the upper side of the stator 2, and the rotor shaft 1 is passed through the rotor shaft hole 32a of the rotor disk 32A. Assemble in such a positional relationship. At this time, the rotor disk 32A positioned and held on the upper end side of the bearing holding member 25 has a positional relationship such that a gap dimension designed in advance is formed on the opposing surfaces of the permanent magnet 31 and the stator core 22. ing.

Finally, the upper and lower covers 8 in FIG. 2 are attached to the housing by a method such as adhesion.
A circuit board for a three-phase power supply to be supplied to each pole component of the stator 2 may be provided inside one cover 8.

  In the rotating electrical machine 101 according to the present embodiment, the rotor shaft 1 is a straight shaft, and the inner rings of the ball bearings 5 and 5 and the rotor shaft holes 32a and 32a of the rotor disks 32A and 32B are fixed by press-fitting. However, in actuality, it is possible to maintain the dimensional relationship in the axial direction with high accuracy by using a stepped shaft. Since the bearing holding member 25 and the iron core holding member 21 are firmly fixed to the housing 4, a rotation output from the rotor shaft 1 (output shaft) can be obtained with the housing 4 fixed to the outside. It has a structure.

<< Modification of First Embodiment >>
In the present embodiment, the radially outer side of the disk base portion region 21d (see FIG. 3) of the core holding member 21 is configured as the core holding regions 21a and 21b separated in the circumferential direction. Instead, it may simply be in the shape of an annular disk area in which substantially fan-shaped holes or grooves 21c ₁ and 21c ₂ are formed. In that case, it is not necessary to provide the notch portion 21e, and if necessary, a part of the outer peripheral portion may be protruded outward by a certain amount.

  According to this embodiment and its modification, since the iron core holding member 21 is made of engineering plastic, eddy current does not occur in the iron core holding member 21 due to the rotation of the rotors 3A and 3B, and iron loss is reduced. A low-efficiency rotating electric machine can be realized.

<< Second Embodiment >>
Next, a second embodiment of the present invention will be described with reference to FIGS.
In the first embodiment, the iron core holding member 21 and the bearing holding member 25 are made of high-strength engineering plastic and are integrally molded. However, the present invention is not limited to this.
In this embodiment, the iron core holding member 21 and the bearing holding member 25 are manufactured separately, and the iron core holding member 21 is made of a high-strength metal material such as, for example, an aluminum alloy or a steel plate. 3 having substantially the same cross-sectional shape as the stator core 22 as shown in FIG. 3 in the first embodiment having a circular hole for fitting the substantially cylindrical bearing holding member 25 made of steel. A substantially disk shape in which holes or grooves 21c ₁ and 21c ₂ having a shape are formed. Then, the bearing holding member 25 is fitted into and fixed to the hole at the center of the iron core holding member 21 by a method such as press fitting, shrink fitting, gap fitting or the like.
Incidentally, the bearing holding member 25 has the same shape as that of the first embodiment.

Further, the stator core 22, before fitting secured in the hole or groove 21c _1, 21c _2, the side surfaces of the holes or grooves 21c _1, 21c ₂ of the edge portion and the stator core 22 in at least one is electrically insulating After that, the stator core 22 is pressed into the holes or grooves 21c ₁ and 21c ₂ by a method such as press fitting, shrink fitting, gap fitting, and the like. Secure to.
As a coating for electrical insulation, a coating made of a non-conductive material such as ceramic or resin is difficult to peel off during press-fitting or the like, which is more convenient than mere painting. In the case of painting, baking painting is preferable.

The distance from the axis (rotation center axis) of the rotor shaft 1 at the radially outer end of the edge 21a ₁ is set slightly larger than that at the radially outer end of the edge 21b ₁ . Therefore, when the stator 2 is assembled in the housing 4, the outer peripheral surface of the edge portion 21 a ₁ and the inner peripheral surface 4 a (see FIG. 9) of the housing 4 abut, and the outer peripheral surface of the edge portion 21 b ₁ and the inner peripheral surface of the housing 4. A gap is formed between the surface 4a.
Further, in the first embodiment, as described with reference to FIG. 3, between the circumferential end of the circumferential end and 21b ₁ edge 21a ₁ adjacent in the circumferential direction, and the circumferential adjacent direction edges 21b _A notch 21e is formed between the circumferential end of _{1 and} the circumferential end of 21b ₁ , and between adjacent iron core holding regions 21a and 21b and between adjacent iron core holding regions 21b and 21b. Is cut off on its radially outer side.

  When the stator 2 (see FIG. 1) in the present embodiment is incorporated in the housing 4, the housing 4 and the stator 2 are connected to each other using a method such as shrink fitting, press fitting, gap fitting, or the like in the axial direction of the rotor shaft 1. It can be fixed. At this time, since the core holding member 21 is made of a material having a sufficiently high strength, it can withstand the stress of press fitting or shrink fitting.

Further, when the stator 2 is incorporated in the housing 4, the outer peripheral surface of the edge portion 21 a ₁ and the inner peripheral surface 4 a (see FIG. 9) of the housing 4 abut, and the outer peripheral surface of the edge portion 21 b ₁ and the inner surface of the housing 4 Since a gap is formed between the peripheral surface 4a and the peripheral surface 4a, an eddy current is generated in the iron core holding member 21 in a direction that prevents the magnetic flux from flowing through the stator core 22 of the rotating electrical machine 101. However, even if the housing 4 is made of a conductive member such as a steel plate or an aluminum alloy, the current path flowing around the stator core 22 can be interrupted. Of course, when the housing 4 is made of a conductive member such as a steel plate or an aluminum alloy, as described above, at least _one of the outer peripheral surface of the edge portion 21a ₁ and the inner peripheral surface 4a of the housing 4 is electrically insulated. It is desirable to keep it.

Further, since at least one of the side surface of the stator core 22 and the substantially fan-shaped holes or the edges of the grooves 21c ₁ and 21c ₂ is electrically insulated, the core holding member that holds the stator core 22 is used. The generation of eddy current loss due to electrical conduction between the holes 21 or the edges of the grooves 21c ₁ and 21c ₂ and the stator core 22 can be suppressed.
According to this embodiment, since the bearing holding member 25 and the iron core holding member 21 are structured to be firmly fixed to the housing 4, the structure in which the housing 4 is fixed to the outside is more than that in the case of the first embodiment. The structure is such that a larger rotational output from the rotor shaft 1 (output shaft) can be obtained.

<< Third Embodiment >>
Next, a rotating electrical machine according to a third embodiment will be described with reference to FIGS. 10 to 14.
FIG. 10 is a partial cross-sectional perspective view of the rotating electrical machine according to the third embodiment, and FIG. 11 is an exploded perspective view in which components of the rotating electrical machine according to the third embodiment are developed in the rotor axial direction.

As shown in FIG. 10, this axial gap type rotating electrical machine 105 (hereinafter simply referred to as “rotating electrical machine 105”) is configured such that the stator 2 in the first embodiment or the second embodiment described above is a rotor in two stages. The rotor 3A according to the first embodiment is disposed above the upper stator 2 in FIG. 10 and is stored between the upper and lower stators 2 and 2 in the housing 4 in the axial direction of the shaft 1. The rotor 3C, which is an intermediate rotor, is disposed, and the rotor 3B according to the first embodiment is disposed below the lower stator 2 in FIG. 10, and both axially outer side surfaces of the rotor shaft 1 (FIG. 10). Is covered with a disk-shaped cover 8 having a rotor shaft hole 8a (see FIG. 11) at the center thereof.
Incidentally, the rotating electrical machine 105 is a three-phase permanent magnet synchronous motor.

In the first and second embodiments, each of the bearing holding holes 25a and 25a (see FIGS. 1 and 3) on both sides in the axial direction of the rotor shaft 1 of the bearing holding member 25 constituting the stator 2 is provided with a ball bearing. In this embodiment, the ball bearing 5 is fitted into the upper bearing holding hole 25a of the bearing holding member 25 constituting the upper stage stator 2 in FIG. 2 differs from the first and second embodiments in that the ball bearing 5 is fitted in the lower bearing holding hole 25a of the bearing holding member 25 constituting the bearing 2.
The same code | symbol is attached | subjected to the same structure as 1st Embodiment or 2nd Embodiment, and the overlapping description is abbreviate | omitted.

(Intermediate rotor)
Next, the configuration of the rotor 3C, which is an intermediate rotor, which is a feature of this embodiment, will be described with reference to FIG. 12A and 12B are explanatory views of a magnet holding method for the intermediate rotor of the rotating electrical machine according to the third embodiment, wherein FIG. 12A is an exploded perspective view and FIG. 12B is an assembled perspective view.
The rotors 3A and 3B have a structure in which the rotor disks 32A and 32B constitute a yoke portion (back yoke) for the permanent magnet 31. In the rotor 3C, the rotor disk (field pole holding member) 32C is the permanent magnet 31. Does not constitute a yoke part for That is, the rotor disk 32C is preferably made of a non-magnetic material or a non-conductive material. For example, the rotor disk 32C has a substantially disk-like structure made of high-strength engineering plastic. The rotor disk 32C has a rotor shaft hole 32a at the center and a holding hole (magnet holding hole) 32b for holding the permanent magnet 31 with the same periodicity as the arrangement of the permanent magnets 31 in the rotors 3A and 3B. It is provided with a shape. The permanent magnet 31 is structured to be bonded and fixed to the holding hole 32b. Thereby, as shown in FIG. 12B, the permanent magnet 31 of the rotor 3C constitutes a rotor that can be arranged in the rotor disk 32C and can effectively use the surfaces on both sides in the axial direction of the rotor shaft 1. be able to.

  Incidentally, in FIG. 11, the permanent magnet 31 of the rotor 3 </ b> A, the permanent magnet 31 of the rotor 3 </ b> C, and the permanent magnet 31 of the rotor 3 </ b> B arranged at the same position in the circumferential direction are magnetic polarities facing the stator 2 side. For example, N pole (rotor 3A), S pole (upper surface of rotor 3C in FIG. 11), N pole (lower surface of rotor 3C in FIG. 11), S pole (rotor 3B), Alternatively, in order from the top, the S pole (the rotor 3A), the N pole (the upper surface of the rotor 3C in FIG. 11), the S pole (the lower surface of the rotor 3C in FIG. 11), and the N pole (the rotor 3B). To place.

According to the rotating electrical machine 105 of the present embodiment, there are four gap surfaces that contribute to torque output, and a rotating electrical machine 105 with a large output can be obtained. The axial gap type rotating electrical machine has a feature that is flat in the axial direction of the rotor shaft 1, and in order to increase the output, it is necessary to increase the diameter. By rotating the stator and the intermediate rotor in the axial direction of the rotor shaft 1, it is possible to obtain a rotating electrical machine with a large output.
As for the method of fixing the stator 2 to the housing 4, the axial direction of the rotor shaft 1 of the stator 2 when the stator 2 is fixed in the housing 4 by changing the inner diameter of the housing 4 to be stepped. It is also possible to improve the positioning accuracy.

(First modification of magnet fixing method for intermediate rotor)
Next, the structure of a rotor 3D, which is a first modification of the rotor 3C that holds the permanent magnet 31B so as to have the same structure as described above, will be described with reference to FIG.
FIG. 13 is a diagram for explaining a first modification of the magnet holding method for the intermediate rotor of the rotating electrical machine according to the third embodiment, where (a) is an exploded perspective view and (b) is an assembled perspective view. It is.
The rotor 3D is composed of two rotor disk single-sided surfaces (field pole holding members) 33A and 33B having a rotor shaft hole 33a in the center, and a permanent magnet 31B held between the rotor discs. As shown in FIG. 13A, the permanent magnet 31B has substantially radial grooves 31a ₁ and 31a ₂ on both surfaces. And rotor disk single side 33A, 33B has the holding hole (magnet holding hole) 33b for holding the permanent magnet 31B similarly to the holding hole 32b (refer FIG. 12) of the rotor 3C, but the permanent magnet of the holding hole 32b. 31 is a bridge portion for restraining the movement of the permanent magnet 31B in the axial direction of the rotor shaft 1 at a position corresponding to the grooves 31a ₁ and 31a ₂ and facing the stator 2 (see FIG. 11). 33c ₁ and 33c ₂ are provided. The bridge portions 33c ₁ and 33c ₂ are configured to be thinner than the thickness of the rotor disk single surfaces 33A and 33B in the axial direction of the rotor shaft 1, and the portions of the permanent magnets 31B corresponding to the positions of the bridge portions 33c ₁ and 33c ₂ are formed. The thickness of the rotor shaft 1 in the axial direction is not significantly reduced. Incidentally, the two rotor disk single faces 33A and 33B are configured such that the thickness of the rotor 3D does not become larger than the maximum thickness of the permanent magnet 31B.

The permanent magnet 31B is disposed between the rotor disk single faces 33A and 33B, and the rotor disk single faces 33A and 33B and the permanent magnet 31B are assembled with an adhesive as shown in FIG.
The permanent magnet 31B exposes the magnetic pole face from the windows 33b ₁ and 33b ₂ (see FIG. 13A) of the holding hole 32b on the stator 2 side (see FIG. 11).
In FIG. 13, the grooves 31a ₁ and 31a ₂ and the bridge portions 33c ₁ and 33c ₂ are provided at substantially the same circumferential position in the radial direction, but the present invention is not limited to this. In order to increase the strength of the grooves 31a ₁ and 31a ₂ of the permanent magnet 31B, the bridge portions 33c ₁ and 33c ₂ may be arranged in an X shape, for example, and the grooves 31a ₁ and 31a ₂ may be provided correspondingly. good.

By fixing the permanent magnet 31B to the rotor 3D as in this modified example, the bonding area increases from the bonding surface between the permanent magnet 31 and the edge of the holding hole 32b in the rotor 3C, and the bridge portions 33c ₁ and 33c. _{With the} holding by _2, the holding function of the permanent magnet 31B of the rotor 3D against the attractive force or repulsive force of the rotor shaft 1 with respect to the permanent magnet 31B is strengthened, and the possibility of the permanent magnet 31B dropping off can be reduced. In addition, a thin intermediate rotor can be configured in the axial direction of the rotor shaft 1.

(Second modification of intermediate magnet fixing method)
Next, the structure of a rotor 3E, which is a second modification of the rotor 3C that holds the permanent magnet 31C to have the same structure as described above, will be described with reference to FIG.
FIG. 14 is a diagram for explaining a second modification of the magnet holding method for the intermediate rotor of the rotating electrical machine according to the third embodiment, and (a) is a partial sectional perspective view of the intermediate rotor and the permanent magnets thereof. A perspective view and (b) are the figures explaining the relationship at the time of fixation of the rotor disk of A part and B part and permanent magnet in (a). A rotor disk (field pole holding member) 32D constituting the rotor 3E of this modification has a substantially disk shape having a rotor shaft hole 32a at the center thereof, and is a holding for holding the permanent magnet 31C. The holes (magnet holding holes) 32b are provided with the same periodicity and shape as the arrangement of the permanent magnets 31 in the rotors 3A and 3B.

The permanent magnet 31C attached to the holding hole 32b is a resin-molded magnet that is insert-molded into the holding hole 32b provided in the previously formed rotor disk 32D by means such as injection molding. By such a molding method, the permanent magnet 31C is made to have the axis of the rotor shaft 1 at the peripheral edge of its planar shape as shown in FIG. 14 (b) showing the A part and the B part in FIG. 14 (a). Both sides in the direction are shaped so as to sandwich the edge of the holding hole 32b, and are fixed to the rotor disk 32D. And both axial direction surfaces of the rotor shaft 1 of the permanent magnet 31C are exposed, and the thickness of the rotor disk 32D is configured to be thinner than the permanent magnet 31C.
In addition, what is shape | molded using the resin composite material for ferrite bond magnets which consists of a ferrite and a thermoplastic resin is well known as a resin molding magnet, for example.

  By fixing the permanent magnet 31C to the rotor 3E as in this modification, the attraction in the axial direction of the rotor shaft 1 with respect to the permanent magnet 31C rather than the bonding surface between the permanent magnet 31 and the edge of the holding hole 32b in the rotor 3C. The function of holding the permanent magnet 31C of the rotor 3E against force and repulsive force is strengthened, and the possibility of the permanent magnet 31C dropping off can be reduced. In addition, a thin intermediate rotor can be configured in the axial direction of the rotor shaft 1.

DESCRIPTION OF SYMBOLS 1 Rotor shaft 2 Stator 3A, 3B, 3C, 3D, 3E Rotor 4 Housing 4a Inner peripheral surface 5 Ball bearing 8 Cover 8a Rotor shaft hole 21 Iron core holding member 21a ₁ edge part (1st outer periphery part)
21b ₁ edge (second outer peripheral edge)
21c ₁ , 21c ₂ hole or groove 21 Iron core holding member (stator core holding member)
21a, 21b Iron core holding area 21d Disc base area 21e Notch 22, 22A, 22B, 22D Stator core 23 Coil 23a Winding intermediate part 23b Winding end 25 Bearing holding member (bearing holding member)
25a bearing holding hole 25b rotor shaft hole 31,31B, 31C permanent magnets 31a _1, 31a ₂ grooves 32A, 32B rotor disc 32C, 32D rotor disc (field pole holding member)
32a, 33a Rotor shaft hole 32b, 33b Holding hole (magnet holding hole)
33A, 33B One side of rotor disk (field pole holding member)
33c ₁ , 33c ₂ bridge part 33b ₁ , 33b ₂ window 101, 105 axial gap type rotating electrical machine

Claims (16)

In the axial gap type rotating electrical machine in which the rotor is disposed oppositely across the stator with a predetermined gap along the axial direction of the rotor shaft,
The stator is
A plurality of rod-shaped stator iron cores arranged along the circumferential direction about the axis of the rotor shaft as a central axis and facing the axial direction of the axis of the rotor shaft;
A disk-shaped stator core holding member provided with a plurality of holes or grooves having substantially the same shape as the cross-sectional shape of the stator core along the circumferential direction about the axis of the rotor shaft;
A coil wound around the stator core,
An axial gap type rotating electrical machine, wherein the stator iron core is inserted into the hole or groove of the stator iron core holding member and fixed and held in the vicinity of the central portion in the axial direction thereof.   2. The axial gap according to claim 1, wherein the stator core is fixed to the hole or groove of the stator core holding member using any one of press fitting, shrink fitting, and gap fitting. Type rotating electric machine.   3. The structure according to claim 1, wherein the stator core holding member is fixed to a housing having a cylindrical shape or an inner peripheral surface shape identical to an outer peripheral edge of the stator core holding member. Axial gap type rotating electrical machine.   The axial gap type rotating electric machine according to claim 3, wherein the stator core holding member is fixed to the inner peripheral surface of the housing by using any one of press fitting, shrink fitting, and gap fitting. .   The axial gap type rotation according to any one of claims 1 to 4, wherein the stator core holding member and a bearing holding member disposed radially inward are integrally formed. Electric.   2. A structure in which a holding member of a bearing is fixed in a space provided on a radially inner side of the stator core holding member by any one of press fitting, shrink fitting, and gap fitting. The axial gap type rotary electric machine according to any one of claims 1 to 4.   The axial gap type rotating electric machine according to claim 1, wherein the stator core holding member is made of a non-conductive high-strength polymer material. The stator core holding member is made of a conductive high-strength metal material, and has a radial notch that reaches the hole or groove from the outer periphery thereof,
A first outer peripheral edge in which the outer peripheral edge partitioned in the circumferential direction by the notch contacts the inner peripheral face of a cylindrical housing that houses the stator and the rotor; and an inner peripheral face of the housing The axial gap type rotating electrical machine according to claim 1, comprising a second outer peripheral edge portion that forms a gap therebetween.   At least one of an edge of a hole or groove for fixing and holding the stator core of the stator core holding member and the stator core, a current flows between the stator core holding member and the stator core. The axial gap type rotating electrical machine according to claim 8, wherein an electrical insulating coating is provided so as not to be present.   The axial gap type rotating electric machine according to claim 1, wherein coils for one pole of the stator pole are arranged on both sides in the axial direction of the stator core with the stator core holding member interposed therebetween.   The axial gap type rotating electric machine according to claim 1, wherein two or more stators are arranged in an axial direction of the rotor shaft.   The rotor arranged at a position sandwiched between the stators has a field pole holding member that exposes and holds both sides in the axial direction of the rotor shaft of the permanent magnet constituting the field pole, and does not have a yoke part. The axial gap type rotating electrical machine according to claim 11, wherein the axial gap type rotating electrical machine is configured.   13. The axial gap type rotating electric machine according to claim 12, wherein the field pole holding member holds the permanent magnet sandwiched in the axial direction of the rotor shaft by two disk-like members.   The axial gap type rotating electric machine according to claim 12, wherein the field pole holding member has a magnet holding hole for holding the permanent magnet, and the permanent magnet is attached to the magnet holding hole by resin molding.   15. The stator core according to claim 1, wherein the stator core is made of any one of an amorphous metal, a dust core, and a soft magnetic material having anisotropy in the axial direction. An axial gap type rotating electrical machine described in 1.   The axial gap type rotating electric machine according to any one of claims 1 to 15, wherein the stator core has a substantially fan-shaped cross section.

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