JP7139138B2 - Axial gap type rotary electric machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to an axial gap type rotating electric machine, and more particularly to an axial gap type rotating electric machine characterized by a stator.

2. Description of the Related Art Axial gap type electric rotating machines are known in which a stator and a rotor face each other across a predetermined gap in the rotation axis direction. Axial gap type rotary electric machines are suitable for achieving high power density and high efficiency because they have a thin (flat) structure and can have a large facing area between the stator and the rotor per body size. In addition, there are multiple combinations of stators and rotors in the same rotary electric machine, but in a structure in which the stator is sandwiched between two disk-shaped rotors from the axial direction (hereinafter referred to as 2-rotor-1-stator type) , the stator core can have a simple columnar structure.

Patent document 1 is known as a conventional technology of an axial gap type electric rotating machine. Patent Document 1 discloses a structure in which a yoke and a winding magnetic core (teeth) are divided. Since the division requires holding against magnetic attraction force and torque reaction force, engagement grooves are provided in the division surface to mechanically fasten the yoke and teeth.

JP 2010-29017 A

In the technique disclosed in Patent Document 1, since it is necessary to provide an engaging groove in the yoke, it requires processing work and is costly. By the way, if it is possible to share the parts of the 2-rotor-1-stator axial gap type rotating electric machine and the 1-rotor-1-stator type axial gap type rotating electric machine in which one rotor and stator are arranged facing each other, , the cost can be reduced. For example, it is conceivable to apply a two-rotor structure for high-output specifications and a one-rotor structure for low-output specifications. Furthermore, since permanent magnets account for a large portion of the cost of a rotating electric machine, it is possible to reduce the cost by adopting a single rotor.

However, the 2-rotor-1-stator axial gap type rotating electric machine has a columnar iron core structure, and the 1-rotor-1-stator axial gap type rotating electric machine has a structure of an iron core consisting of teeth and yokes. were different, parts were not common among different types of axial gap type electric rotating machine.

SUMMARY OF THE INVENTION An object of the present invention is to provide a cost-reduced axial gap type rotary electric machine that eliminates the need for processing work to separate yokes and teeth and allows different types of axial gap type rotary electric machines to share an iron core.

A preferred example of the present invention includes a stator having teeth, which are iron cores around which windings are wound, and yokes, which are iron cores separated from the teeth; a first fixing portion fixing the rotor, the teeth, the windings, and a housing provided around the stator with resin; and a second fixing portion fixing the yoke and the housing. It is an axial gap type rotary electric machine having a part.

According to the present invention, it is possible to eliminate the need for processing work for separating the yokes and teeth, and to share the core between different types of axial gap type rotating electric machines, thereby reducing costs.

FIG. 2 is an internal configuration diagram showing the one-rotor-one-stator axial-gap rotating electric machine of the first embodiment; FIG. 10 is an internal configuration diagram showing a one-rotor-one-stator axial-gap rotating electrical machine of Example 2; FIG. 11 is an internal configuration diagram showing a one-rotor-one-stator axial gap rotating electrical machine of Example 3; FIG. 11 is an internal configuration diagram showing a one-rotor-one-stator axial gap rotating electrical machine of Example 4; FIG. 11 is an internal configuration diagram showing a one-rotor-one-stator axial gap rotating electrical machine of Example 5; FIG. 11 is an internal configuration diagram showing a controller-integrated one-rotor-one-stator axial-gap rotating electric machine according to a sixth embodiment; FIG. 11 is an internal configuration diagram showing a mechanical device-integrated 1-rotor-1-stator axial gap rotating electric machine of Embodiment 7; FIG. 5 is an internal configuration diagram showing a two-rotor one-stator type axial gap type rotary electric machine of a comparative example; FIG. 5 is an internal configuration diagram showing a one-rotor-one-stator axial gap rotating electric machine of a comparative example; FIG. 2 is an internal configuration diagram when applied to a one-rotor, two-stator type axial gap type electric rotating machine;

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

1(a) and 1(b) are internal configuration diagrams of a 1-rotor-1-stator axial gap type rotating electric machine 2000 according to the first embodiment. FIG. 1(b) is an axially displaced exploded view of the parts of FIG. 1(a).

In the one-rotor-one-stator axial gap type rotary electric machine 2000 of the first embodiment, as shown in FIGS. 1(a) and 1(b), an annular A stator 100 having a donut shape is fixed. Rotor 200 has a disk shape consisting of permanent magnets 210 and yoke 220 . The permanent magnets 210 are magnetized in the rotation axis direction 101, and are arranged in the circumferential direction such that the magnetic pole directions of adjacent permanent magnets are opposite to each other. Permanent magnet 210 is coupled to yoke 220 . A magnetized surface of the rotor 200 faces the stator with a predetermined gap in the rotation axis direction 101 . Also, the rotor 200 is connected so as to rotate together with the shaft 500 . The axially outer side of the shaft is connected to end bracket 400 via bearing 600 . End brackets 400 are fixed to both ends of housing 300 and rotatably support rotor 200 . The stator 100 has an iron core 110, a bobbin 130 covering the outer periphery of the iron core, and a winding 120 wound around the bobbin 130 arranged in a ring, and fixed integrally with a housing 300 by a mold resin 140. .

Furthermore, iron core 110 of stator 100 is divided into teeth 111 and yoke 112 , and teeth 111 are integrally fixed to housing 300 together with bobbin 130 and winding 120 with mold resin 140 . Teeth 111 and yoke 112 are separated by a plane perpendicular to the rotation axis. Teeth 111 have a columnar shape with a trapezoidal cross section, and yoke 112 has a ring shape. A convex stepped portion 113 is provided on the outer periphery of the yoke 112 on the side of the stator 100 and fixed to a stepped portion 301 provided on the inner periphery of the housing 300 . The stepped portion 301 serves to determine the position of the yoke 112 in the rotation axis direction 101 . By adjusting the dimension of the step portion 113, it is possible to provide a desired gap in the rotation axis direction 101 between the tooth 111 and the yoke 112. FIG.

The operation of the 1-rotor-1-stator axial gap type rotary electric machine thus constructed will be described below using a motor as an example. First, an alternating current flowing through a winding through an inverter or the like generates a rotating magnetic field. Torque is generated by attracting and repulsing the DC magnetic field of the rotor formed by the permanent magnets and the rotating magnetic field of the coil.

Next, a two-rotor one-stator axial gap type rotating electrical machine 1000 as a comparative example will be described with reference to FIGS. 8(a) and 8(b). Differences from FIG. 1 will be mainly described. The magnetized surfaces of the rotor 200 are opposed to both end surfaces of the stator in the rotation axis direction with a predetermined gap therebetween. The stator 100 has an iron core 110, a bobbin 130 covering the outer circumference of the iron core, and a winding 120 wound around the bobbin, which are arranged in a ring. It is designed to be Alternatively, the annularly arranged cores may be integrally resin-molded and then fixed to the housing 300 with bolts or the like.

In this rotating electrical machine, iron core 110 can be configured in a simple columnar shape, so low-loss materials such as amorphous metals and nanocrystals, which are difficult to press punch, can be applied. Also, ideally, since the iron core is attracted to both rotors 200 with equal force, no load is applied to the stator 100 in the axial direction.

A 1-rotor-1-stator type axial gap type rotary electric machine 2000 as a comparative example will be described with reference to FIGS. 9(a) and 9(b). A 1-rotor, 1-stator axial gap rotating electric machine 2000 is composed of a single rotor 200 by using an iron core 110 composed of teeth 111 and a yoke 112 for a stator 100 . The iron core is held by fastening the yoke 112 to the end bracket 400 . Although the use amount of the rotor 200 including the permanent magnets 210 can be reduced by half, the iron core shape becomes complicated, making it difficult to apply low-loss materials that are difficult to work. Moreover, since the iron core is unilaterally attracted to the rotor 200 side, it needs to be firmly held. In the configuration of Patent Document 1, the yoke and teeth are also engaged with each other, and like the configuration in FIG. Furthermore, since the inductance is significantly increased, the voltage is increased if the winding specifications are the same as those of the two-rotor-one-stator axial gap type rotating electrical machine 1000 of the comparative example.

As shown in FIGS. 8 and 9, the two-rotor-one-stator axial-gap rotating electric machine 1000 and the one-rotor-one-stator axial-gap rotating electric machine 2000 have different configurations of iron cores and the like. cannot be shared as is.

Next, the effect of Example 1 will be described. First, in the configuration of the first embodiment, since the iron core consists of simple column-shaped teeth 111 and ring-shaped yoke 112, it can be manufactured by simple processing. In addition, since the independent teeth 111 are integrally molded with the bobbin 130 and the winding 120, assembly is easy. Furthermore, the teeth 111 of the 1-rotor-1-stator axial gap type rotary electric machine 2000 of the first embodiment can be shared with the 2-rotor-1-stator type axial gap type motor.

As for the suction force, which is a demerit of division, in the first embodiment, the first fixing portion that fixes the yoke 112 and the housing 300 via the resin layer, and the teeth 111 and the housing 300 are brought into contact with each other at the steps. It is fixed using a means different from that of the second fixing part that is fixed by pressing. Therefore, on the teeth 111, an attractive force in the direction of the rotor 200 and an attractive force in the direction of the yoke 112 act. As a result, the force acting in the direction of the rotor 200 as a whole is reduced, so the shearing force acting on the resin portion supporting the teeth 111, especially the interface with the housing 300 is reduced. As a result, it is possible to extend the life of the resin portion.

Also, by changing the gap between the teeth 111 and the yoke 112, it is possible to adjust the effective magnetic flux and the inductance. When the windings are specially designed for a 1-rotor-1-stator axial gap type motor, the effective magnetic flux can be maximized by reducing the air gap as much as possible. On the other hand, when the windings are shared with the 2-rotor-1-stator axial gap type motor, it is possible to suppress the increase in voltage by enlarging the air gap and reducing the inductance.

The teeth 111 and the yoke 112 of the present embodiment may be a magnetic material having high insulating properties, and may be a magnetic steel sheet, an amorphous metal, a nanocrystalline material, or the like laminated in the radial direction, or a pressure-dividing magnetic core. you can In particular, soft-workable amorphous metals and nanocrystalline materials are difficult to fabricate into complex shapes while ensuring high mass productivity, so the effect of applying this embodiment is significant.

The tooth 111, the bobbin 130, and the winding wire 120 of the first embodiment are integrally fixed with the housing 300 by molding resin. may Although the yoke 112 is fixed to the stepped portion 301 of the housing 300, it may be fixed in the rotation axis direction 101 and may be fixed by bolts, screws, or the like.

In the first embodiment, an example in which teeth are shared in two-rotor-one-stator and one-rotor-one-stator axial gap motors is shown, but other configurations are also applicable. For example, the stator 100 of this embodiment may be applied to a 1-rotor, 2-stator stator in which a disk rotor is axially sandwiched between two stators.

The second embodiment will be described below. Descriptions overlapping those of the first embodiment are omitted.
2(a) and 2(b) are internal configuration diagrams of a 1-rotor-1-stator axial gap type rotating electric machine 2000 of the second embodiment. FIG. 2(b) is an axially displaced exploded view of the parts of FIG. 2(a). In this embodiment, the yoke 112 is divided into the peripheral portion facing the teeth 111 and the other portion, and the periphery of the teeth 111 is made of a highly insulating magnetic material as the yoke 112, such as an electromagnetic steel plate, an amorphous metal, or a nanocrystalline material. are laminated in the radial direction, or composed of a dust core or the like. On the other hand, the other portion is made of iron, SUS, aluminum, resin, or the like as a holding member 150 that holds the yoke 112 . The holding member 150 has a stepped portion 151 protruding in the rotation axis direction 101 on its outer periphery, and is fixed to the stepped portion 301 of the housing 300 here.

With this structure, the yoke 112 does not need to be provided with a stepped portion, and can be formed in a simple ring shape with a constant thickness. This facilitates fabrication of the yoke 112. FIG. Also, when the yoke 112 has a laminated structure such as a wound iron core, mechanical holding is facilitated. As a result, it becomes easier to use amorphous metals and nanocrystalline materials, which are difficult to process, as the yoke 112, and high efficiency can be achieved.

As in the first embodiment, the second embodiment shows an example in which teeth are shared in two-rotor-one-stator and one-rotor-one-stator axial gap motors, but other configurations are also applicable. For example, as shown in (a) and (b) of FIG. may be applied. Here, FIG. 10(b) is an exploded view in which the parts of FIG. 10(a) are displaced in the axial direction. In this motor configuration, it is necessary to form the magnetic poles of the rotor on the surfaces facing the respective stators. In this figure, magnetic poles are formed on both surfaces of the rotor by supporting the side surfaces of the magnets magnetized in the rotation axis direction with the holding members. In this embodiment, any motor may be used as long as it has a stator core with at least teeth and a yoke, and the combination of the rotor and the stator is arbitrary. The same applies to the subsequent examples.

Example 3 is described below. Descriptions overlapping those of the first embodiment are omitted. 3(a) and 3(b) are internal configuration diagrams of a one-rotor-one-stator type axial gap type rotary electric machine 2000 of the third embodiment. FIG. 3(b) is an axially displaced exploded view of the parts of FIG. 3(a). In Embodiment 3, the holding member 150 and the end bracket 400 are shared, and the holding member 150 is arranged as the end bracket 400 at the end of the housing.

Since this structure reduces the number of parts, it is possible to reduce costs. Since the work inside the housing 300 becomes unnecessary, the ease of assembly is also improved. It is also possible to make the motor thinner.

Example 4 is described below. Descriptions overlapping those of the first embodiment are omitted. FIG. 4 shows a schematic configuration of a one-rotor, one-stator type axial gap type rotary electric machine according to a fourth embodiment.

In an inverter-driven motor, common-mode voltage is electrostatically coupled from the windings to the rotor 200, thereby generating a voltage between the inner and outer rings of the bearing (hereinafter referred to as shaft voltage). If the shaft voltage increases, electrical discharge will cause dielectric breakdown of the oil film, resulting in damage to the bearing surface and shortening of the bearing life.

Up to now, the wires drawn out from the windings 120 have been wound around in the circumferential direction as the connecting wires 121 in the space between the rotor 200 and the housing 300 . In this case, it is known that the voltage of the crossover wire 121 is also electrostatically coupled with the side surface of the rotor 200, causing an increase in the shaft voltage.

Therefore, in the fourth embodiment, a groove for arranging the connecting wire 121 is provided between the holding member 150 and the housing 300, which are located in a direction opposite to the rotor 200 and away from the rotor 200. , and a crossover 121 is arranged. This structure reduces the shaft voltage and extends the life of the bearing.

Example 5 is described below. Descriptions overlapping those of the first embodiment are omitted. FIG. 5(a) is an internal configuration diagram of a one-rotor-one-stator type axial gap type rotary electric machine 2000 of the fifth embodiment. FIG. 5(b) is an enlarged view of the periphery of the heat conductor 160 in FIG. 5(a).
In this embodiment, a heat conductor 160 is arranged in the gap between the tooth 111 and the yoke 112. As shown in FIG.

This structure reduces thermal resistance from teeth 111 to yoke 112 . This improves heat dissipation from the windings, which are the main heat source. As a result, the 1-rotor-1-stator axial gap type rotary electric machine 2000 can be improved in output, efficiency, and size reduction.

Magnetic flux interlinks in the air gap, so the heat conductor is preferably made of a non-conductive member. For example, a thin plate of electromagnetic SUS, a thermally conductive sheet such as silicone or ceramic, or a silicone adhesive may be used. In addition, if a gap is intentionally provided to reduce the inductance, a non-magnetic heat conductor is desirable, so a heat conductive sheet such as silicone or ceramic, a silicone adhesive, or the like may be used.

Example 6 is described below. Descriptions overlapping those of the first embodiment are omitted. FIG. 6 is an internal configuration diagram of a one-rotor-one-stator type axial gap type rotary electric machine 2000 of the sixth embodiment. In this embodiment, a control device 700 used for driving the one-rotor, one-stator axial gap type rotary electric machine 2000 is arranged on the opposite side of the holding member 150 from the stator 100 .

With this structure, the hatched control device 700 and the one-rotor, one-stator axial gap rotating electric machine 2000 can be configured more compactly. In addition, since the control device is housed in the rotating electric machine covered by the housing 300 and the end bracket 400, dustproof and waterproof measures for individual control devices are unnecessary. Since the wiring between the control device and the rotating electric machine is reduced, it leads to a reduction in radiation noise and a reduction in costs.

Example 7 is described below. Descriptions overlapping those of the first embodiment are omitted. FIG. 7 is an internal configuration diagram of a one-rotor-one-stator type axial gap type rotary electric machine 2000 of the seventh embodiment. In this embodiment, mechanical devices are arranged ahead of the rotor 200, and a 1-rotor-1-stator axial gap type rotating electric machine 2000 functioning as a motor, and a hatched scroll which is an example of the mechanical device. The compression mechanism 800 of the air compressor is integrated.

With this structure, the mechanical device and the motor can be configured more compactly. Although the compression mechanism of the scroll air compressor is integrated in this embodiment, other mechanical devices such as a fan and a pump may be integrated.

2000 1 rotor-1 stator type axial gap type rotary electric machine, 100 stator, 110 iron core, 111 teeth, 112 yoke, 113 steps, 120 windings, 121 connecting wires, 140 mold resin, 150 holding members, 151 steps, 160 thermal conductors, 200 rotors, 220 yokes, 300 housings, 301 shoulders, 400 end brackets, 500 shafts

Claims (11)

A stator having teeth, which are iron cores wound with windings, and yokes, which are iron cores separated from the teeth;
a rotor arranged with a gap between the stator and the rotating shaft direction;
a first fixing portion in which the teeth, the windings, and a housing provided around the stator are fixed with resin;
An axial gap type electric rotating machine, comprising: a second fixing portion for fixing the yoke and the housing by fixing a step portion provided on the yoke to a step portion provided on the housing. In the axial gap type rotary electric machine according to claim 1,
An axial gap type rotary electric machine, comprising a holding member that holds the yoke, and the holding member is fixed to the housing. 3. The axial gap type rotary electric machine according to claim 2 , wherein said holding member is arranged as an end bracket at an end of said housing. In the axial gap type rotary electric machine according to claim 1,
An axial gap type electric rotating machine, wherein a crossover wire, which is formed by extending lead wires from the windings, is arranged in a direction opposite to the rotor in the circumferential direction of the housing. In the axial gap type rotary electric machine according to claim 1,
An axial gap type electric rotating machine, wherein a heat conductor is arranged between the teeth and the yoke. 3. The axial gap type rotary electric machine according to claim 2 , wherein a control device used for driving is arranged on the side opposite to the stator with respect to the holding member. In the axial gap type rotary electric machine according to claim 1,
An axial gap type electric rotating machine, characterized in that a mechanical device is connected to the tip of the rotor. In the axial gap type rotary electric machine according to claim 1,
An axial gap type electric rotating machine, wherein the teeth or the yokes are made of a material selected from low-loss materials such as amorphous metals and nanocrystals. In the axial gap type rotary electric machine according to claim 1,
An axial gap type electric rotating machine, wherein the teeth can be shared by different types such as a 2-rotor-1-stator type or a 1-rotor-1-stator type. In the axial gap type rotary electric machine according to claim 1,
An axial gap type electric rotating machine, wherein the windings can be shared by different types such as a 2-rotor-1-stator type or a 1-rotor-1-stator type. In the axial gap type rotary electric machine according to claim 1 ,
An axial gap type electric rotating machine, wherein a gap formed between the teeth and the yoke is changed by the second fixing portion so that different types of the axial gap type rotating electric machine can be used in common.

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