JP2016077067A - Axial gap type rotary electric machine and manufacturing method for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an axial gap motor having a low iron loss and high mass productivity.SOLUTION: An axial gap type rotary electric machine includes: a rotor; and stator arranged so as to face the rotor in the rotation axis direction. The rotor or stator includes a yoke and teeth. The teeth are formed on the yoke in the rotation axis direction; the yoke and teeth are formed in a spiral shape as seen from the rotation axis direction; the teeth have a trapezoidal shape as seen from the rotation axis direction.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an axial gap type rotating electrical machine and a method for manufacturing the same.

  While accelerating energy saving and de-rare earth, it is an urgent task to increase the efficiency and output of motors. When classified by the magnetic flux flow direction of the magnet motor, there are a radial motor in which the main magnetic flux is in the radial direction and an axial gap motor in which the main magnetic flux is in the axial direction. Currently, the mainstream motor is a radial gap motor. Axial gap motors are thin and large in the axial direction, and are expected to be put to practical use in the industrial, automotive and flywheel fields.

  Mass production technology has not yet been established for axial gap motors. There are various causes. For example, the structure of the rotor and the stator is high in mass production cost, and the air gap between the rotor and the stator is difficult to manage. Patent Document 1 and Patent Document 2 disclose various axial gap motor structures and techniques.

  In order to reduce the iron loss of the motor, it is desirable to use a laminated core as the rotor and the stator core. Conventionally, a plurality of electromagnetic steel plates punched into a predetermined shape are laminated in the radial direction to constitute a stator iron core. In this case, each laminated iron core needs to be arranged and fixed in the circumferential direction.

  In Patent Document 1, a hole is provided in each laminated body, and it is inserted into a yoke and fixed. On the other hand, Patent Document 2 discloses a method of manufacturing an axial gap SR motor using a wound iron core for the rotor and the stator. In an iron core of an axial gap SR motor, a plurality of salient pole portions are formed by overlapping a plurality of teeth portions continuously provided on one side in the longitudinal direction of the belt-shaped electromagnetic steel sheet.

JP 2012-019582 A JP 2004-222384 A

  In order to put an axial gap motor into practical use, a stator structure and a manufacturing method that can be manufactured at low cost are required. A laminated core is desirable to improve motor efficiency.

  In Patent Document 1, an interposing member is provided between electromagnetic steel sheet laminates to form iron core teeth, and the iron core teeth are inserted into bark yokes laminated in the axial direction. Since the back yoke is laminated in the axial direction, the main magnetic flux passes through the surface of the back yoke. Therefore, eddy current loss occurs in the back yoke. From the viewpoint of manufacturing, the number of parts of the stator is large and the manufacturing cost is high, so that the mass productivity is not good.

  Regarding the SR motor manufacturing method and technology disclosed in Patent Document 2, the width of the stator salient pole is constant so that the rotor salient pole and the stator salient pole can overlap when the motor rotates. . As a cylindrical stator core, the inner width is narrower than the outer width. When the salient pole portion has a constant width, the thickness to be wound is determined. For this reason, a thick stator iron core cannot be comprised in radial direction.

  Therefore, an object of the present invention is to provide an axial gap motor with low iron loss and good mass productivity.

  The features of the present invention for solving the above problems are as follows, for example.

  An axial gap rotating electrical machine having a rotor and a stator disposed opposite to the rotor in the rotation axis direction, wherein the rotor or the stator has a yoke and teeth, and in the rotation axis direction, the teeth are on the yoke. An axial gap type rotating electrical machine in which the yoke and teeth are formed in a spiral shape when viewed from the direction of the rotation axis, and the teeth are trapezoidal when viewed from the direction of the rotation axis.

  According to the present invention, an axial gap motor with low iron loss and good mass productivity can be provided. Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

1 is an overall view of a rotating electrical machine related to Example 1. FIG. The exploded view of the rotary electric machine which concerns on FIG. The magnetized arrangement of the rotor magnet in the first embodiment. The structure of the stator iron core regarding Example 1. FIG. The spiral iron core regarding Example 1. FIG. Part of the magnetic ribbon in which the slit relating to Example 1 was formed. The cross section of the stator teeth regarding Example 1. Sectional drawing of the rotary electric machine regarding Example 1. FIG. FIG. 3 is an example of a structure of a stator iron core related to Example 1. FIG. Sectional drawing of the rotary electric machine regarding Example 1 An example of the rotary electric machine regarding Example 2. FIG. Sectional drawing of the rotary electric machine regarding Example 2. FIG. The rotor magnetization arrangement | positioning of the rotary electric machine regarding Example 2. FIG. A part of the magnetic ribbon in which the slit concerning Example 2 was formed. 6 shows a stator iron core according to the second embodiment. 6 shows a stator iron core according to the second embodiment. The structure of the rotary electric machine regarding Example 3. FIG. 7 is a cross section of a rotating electrical machine according to a third embodiment. Sectional drawing of the rotary electric machine regarding Example 3. FIG. Sectional drawing of the rotary electric machine regarding Example 4. FIG. Sectional drawing of the rotary electric machine regarding Example 3. FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following description shows specific examples of the contents of the present invention, and the present invention is not limited to these descriptions. Various modifications by those skilled in the art are within the scope of the technical idea disclosed in this specification. Changes and modifications are possible. In all the drawings for explaining the present invention, components having the same function are denoted by the same reference numerals, and repeated description thereof may be omitted.

  FIG. 1 shows an overall view of a rotating electrical machine according to an embodiment of the present invention. For the sake of clarity, FIG. 2 shows an exploded view of the rotating electrical machine according to FIG. The rotating electrical machine according to FIG. 1 is an axial gap type rotating machine.

  The rotating electrical machine 1000 in this embodiment has two rotors 100, and the rotor 100 and the stator 200 are opposed to each other along the parallel rotation axis direction, and the two rotors 100 sandwich the stator 200. In other words, the stator 200 is disposed to face the rotor 100 in the rotation axis direction.

  In FIG. 2, the rotor 100 has a ring-shaped rotor magnet 110, a rotor core 120, and a yoke for holding them. The yoke is not shown in the figure. The rotor magnet 110 is composed of a magnet.

  Stator 200 has stator iron core 210 having stator yoke 211 and stator teeth 212, stator teeth 212, and winding coil 220 wound around each. The stator teeth 212 are formed on both sides of the stator yoke 211 in the rotation axis direction. The stator teeth 212 are formed on the stator yoke 211 in the rotation axis direction. Insulators (not shown) such as insulating paper and bobbins are formed between the stator teeth 212 and the winding coils 220.

  FIG. 3 shows the magnetization arrangement of this embodiment. The rotor magnet 110 is magnetized in parallel and is attached to the rotor core 120. The rotor core 120 is composed of a magnetic ring plate. In the circumferential direction, the magnetic poles of the rotor magnet 110 are different from each other. In the rotation axis direction, the two rotor magnets 110 face each other and have the same magnetic pole.

  FIG. 4 shows the structure of the stator core according to this embodiment. The stator core 210 has a stator tooth 212 and a stator yoke 211. A status lot 213 is formed between the stator teeth 212 in the circumferential direction of the stator core 210.

  The stator core 210 has a structure in which magnetic ribbons are laminated in the radial direction. The stator teeth 212 and the stator yoke 211 are composed of continuous magnetic ribbons. Since the stator teeth 212 and the stator yoke 211 are continuous, the stator teeth 212 can be easily held and the strength of the stator 200 can be improved. The cross section of the stator teeth 212 viewed from the rotational axis direction is substantially trapezoidal. By making the stator teeth 212 substantially trapezoidal, the space of the status lot 213 can be used effectively, and the space factor of one slot (stator teeth 212 + winding coil 220) can be increased. When the stator teeth 212 are substantially trapezoidal, the sides adjacent to the stator teeth 212 are parallel to each other, so that even if the diameter of the stator 200 is increased, the space for forming the winding coil 220 is not reduced. Can be enlarged.

  The width of the stator teeth 212 increases from the inner diameter to the outer diameter. The status lot 213 between the stator teeth 212 and the stator teeth 212 is substantially rectangular. In the radial direction, the circumferential width of the status lot 213 is constant and does not change depending on the diameter. Thereby, it becomes easy to arrange the winding coil 220, and the space of the status lot 213 can be used effectively.

  There are several methods for manufacturing the stator core 210. Conventionally, wire processing is performed on a spiral iron core, and the slot portion is formed by punching. FIG. 5 shows a spiral iron core. Before performing the slit processing, it is necessary to perform resin molding on the spiral iron core. Moreover, since the cost of wire processing is high, it is difficult to apply to mass production.

  In this embodiment, the iron core is formed by winding a punched magnetic ribbon. FIG. 6 (A) shows a part of the magnetic ribbon punched out by press working. Since the width a of the portion punched out of the magnetic ribbon 300 is constant, there is no need to change the press teeth. Since the magnetic ribbon 300 is made of one kind of material and the stator core 210 is also made of one kind of material, the cost can be suppressed. The stator yoke 211 has a disk shape and is easily mass-produced. As the diameter of the magnetic ribbon 300 is increased, the width b of the stator teeth 212 is gradually increased. When the magnetic ribbon 300 is punched, the width b of the stator teeth 212 can be controlled by changing the speed at which the magnetic ribbon 300 is transmitted.

  FIG. 6B shows a cross section of the stator core 210 around which the magnetic ribbon 300 is wound. The stator yoke 211 and the stator teeth 212 are configured by winding a magnetic ribbon 300 in which continuous slits are formed. Thereby, when viewed from the rotation axis direction, the stator yoke 211 and the stator teeth 212 are formed in a spiral shape. Due to the width b of the stator teeth 212, the stress and winding speed at which the magnetic ribbon 300 is wound, the unevenness 214 is formed on the shared side of the stator teeth 212 and the status lot 213. The unevenness 214 can be made flat by post-processing. A slight unevenness 214 has little effect on motor performance.

  FIG. 7 shows a cross-sectional view of the rotating electrical machine according to this embodiment. The main magnetic flux passes through the stator teeth 212 from the N pole of the rotor 100 on the upper side in FIG. 7 and enters the S pole of the rotor 100 via the stator yoke 211. The magnetic flux generated from the rotor 100 on the lower side of FIG. 7 flows in the same manner as the magnetic flux generated from the rotor 100 on the upper side of FIG.

  Since the main magnetic flux is perpendicular to the stacking direction of the stator core 210, the iron loss is very small. Further, since the main magnetic flux passes through the stator yoke 211, the spatial harmonics generated by the status lot 213 between the rotor 100 and the stator 200 can be reduced. Therefore, the cogging torque of the motor can be made very small.

  FIG. 8A shows an example of the structure of the stator core according to this embodiment. The stator teeth 212 and the stator teeth 212 at both ends of the stator core 210 are characterized by being displaced in the direction of the rotation axis.

  FIG. 8B shows a cross section of the rotating electrical machine. The rotor 100 on the upper side in FIG. 8B and the rotor 100 on the lower side in FIG. 8B have the same magnetic poles facing each other in the rotation axis direction. The stator teeth 212 corresponding to the rotor 100 on the upper side in FIG. 8B and the stator teeth 212 facing the rotor 100 on the lower side in FIG. 8B are displaced in the rotational axis direction. ing. As a result, the magnetic flux penetrating through the stator core 210 is not concentrated in one place, so that the core saturation can be reduced when a strong magnet or a large current is applied. Furthermore, since the magnetic flux density of the stator core 210 can be reduced, iron loss can be reduced.

  FIG. 9A shows an example of a rotating electrical machine according to this embodiment. The rotating electrical machine 1000 in this embodiment is composed of one rotor and one stator.

  FIG. 9B shows a cross-sectional view of the rotating electrical machine. The main magnetic flux enters the rotor core 120 from the rotor 100 via the stator teeth 212, the stator yoke 211, and the stator teeth 212. The rotor 100 has a structure in which a ring-shaped rotor magnet 110 is fixed to a flat rotor core 120.

  FIG. 10 shows the rotor magnetized arrangement of the rotating electrical machine according to this embodiment. As shown in FIG. 10 (example of 8 poles), the N pole and the S pole are alternated in the magnetizing direction of the rotor magnet 110. The rotor core 120 is composed of a magnetic plate or a wound iron core wound in a spiral shape. The rotor core 120 and the rotor magnet 110 are held by a yoke (not shown) and attached to a rotating shaft.

  FIG. 11 shows a part of a magnetic ribbon having slits. By punching on one side in the longitudinal direction of the magnetic ribbon 300, a slit having a constant width a of the portion where the magnetic ribbon 300 is punched is formed. The width b of the stator teeth 212 increases in the direction opposite to the direction in which the magnetic ribbon 300 is fed.

  FIG. 12A and FIG. 12B show a stator iron core wound with a magnetic ribbon having a slit. The beginning and end of winding of the magnetic ribbon 300 are fixed by welding or an adhesive. In order to form the stator core 210, unevenness 214 is formed in the circumferential direction on the side shared by the stator teeth 212 and the status lot 213 depending on the tension, speed and slitting accuracy for winding the magnetic ribbon 300. Depending on the requirements of the application product of the rotating electrical machine, the unevenness 214 can be removed by post-processing. The stator core 210 shown in FIG. 12A is formed with unevenness 214, and the stator core 210 shown in FIG. 12B is not formed with unevenness 214.

  Since the stator core 210 formed in this embodiment is composed of a continuous magnetic ribbon 300 with the stator teeth 212 and the stator yoke 211, the entire stator core 210 can be held without a resin mold. With the technique disclosed in Patent Document 1, the manufacturing process of the stator iron core is small and the strength is strong. Furthermore, since the stacking direction of the stator yoke 211 is perpendicular to the magnetic flux, the iron loss is very small.

  The width of the stator teeth disclosed in Patent Document 2 is constant. The larger the core diameter, the less space for winding. In this embodiment, since the status lot 213 has a constant width and a space for the winding coil 220 can be secured, the current density can be improved. Although the width of the tip of stator tooth 212 is narrow, saturation of the tip of stator tooth 212 can be prevented by narrowing the width on the inner diameter side of one pole of rotor magnet 110 facing it.

  In this embodiment, an example in which an iron core wound with a magnetic ribbon having slits is applied to a rotor of a rotating electrical machine will be described.

  FIG. 13A shows the structure of the rotating electrical machine according to this embodiment. The rotor core 120 has a rotor yoke 121, a rotor tooth 122, and a rotor slot 123. The rotor teeth 122 and the rotor yoke 121 are configured by winding a magnetic ribbon having a continuous slit. The rotor teeth 122 are formed on the rotor yoke 121 in the rotation axis direction. When viewed from the rotational axis direction, the rotor yoke 121 and the rotor teeth 122 are formed in a spiral shape. In the rotation axis direction, the rotor teeth 122 are trapezoidal. A rotor slot 123 is formed between the rotor teeth 122 in the circumferential direction. In the radial direction, the circumferential width of the rotor slot 123 is constant.

  A rotor magnet 110 is formed in a rotor slot 123 of a wound core provided with a slit. A laminated rotor tooth 122 is provided between the rotor magnet 110 and the rotor magnet 110. With this structure, the leakage magnetic flux between the rotor magnet 110 and the rotor magnet 110 penetrates the rotor teeth 122 and works as a reluctance torque, so that the torque density of the rotating electrical machine 1000 is improved. Since the rotor core 120 has a laminated structure with respect to the magnetic flux, the iron loss of the rotor 100 can be reduced.

  FIG. 13B shows a cross-sectional view of a rotating electrical machine using the rotor of FIG. The magnetic flux generated from the rotor magnet 110 passes through the stator core 210 via the rotor teeth 122 of the laminated rotor core 120. In addition to the main magnetic flux of the motor, the leakage magnetic flux between the rotor magnet 110 and the rotor magnet 110 can be used. Thereby, motor torque can be improved. Furthermore, since the rotor core 120 and the stator core 210 have the rotor yoke 121 and the stator yoke 211, respectively, spatial harmonics can be suppressed. And cogging torque can be reduced.

  FIG. 14 shows a cross-sectional structure of a rotating electrical machine in which two rotors sandwich one stator. The torque can be improved by a factor of 2 over the rotating electrical machine shown in FIG. Since each of the rotor core 120 and the stator iron core 210 uses a wound iron core in which a slit is formed, the iron loss of the rotating electrical machine can be greatly reduced.

  In this embodiment, a flywheel power storage device to which an axial gap motor / generator is applied will be described. FIG. 15 shows a combination of a flywheel and an axial gap type rotating electrical machine. FIG. 16 shows a cross section of FIG.

  In FIG. 15, the flywheel power storage device 3000 has a rotating electrical machine 1000 and a flywheel disk 2000, and the flywheel disk 2000 is attached coaxially with the rotating electrical machine 1000. The fuller wheel disc 2000 and the bearing are arranged in a sealed container. The pressure inside the sealed container is smaller than the atmosphere. The rotating electrical machine 1000 is responsible for the generator and the motor. The rotating electrical machine 1000 is rotated as a motor at a high speed, kinetic energy is stored and charged. When discharging, the rotational speed of the rotating electrical machine 1000 is lowered to the minimum value and electric power is supplied to the load.

  Flywheel energy storage capacity is determined by the speed and moment of inertia of the rotating body. Therefore, it is desirable that the rotating electric machine 1000 to be applied has a thin large diameter and can be rotated at a high speed. When the rotating electrical machine 1000 is operated at a high speed, iron loss and mechanical loss tend to increase. Here, by applying the axial gap type rotating electrical machine disclosed in the first, second, and third embodiments, the loss can be reduced and the diameter of the rotating body can be increased.

  In the axial gap type rotating electrical machine disclosed in the first and second embodiments, the stator teeth 212 are substantially trapezoidal when viewed from the rotation axis direction, and the status lot space 213 in which the winding coil 220 is disposed is rectangular. The diameter of the rotating electrical machine can be increased. Furthermore, since the stator iron core 210 is provided with a stator yoke 211 that passes magnetism, there is little magnetic leakage and the torque density can be improved.

  On the other hand, since the stator teeth 210 and the yoke 211 are laminated in the radial direction, the iron loss of the rotating electrical machine is low, and a reduction in standby loss of the flywheel can be expected.

  In order to reduce the rotor iron loss, it is desirable that the rotor yoke 121 attached to the back of the rotor magnet 110 be a low-loss iron core. By using the winding structure rotor yoke 121 disclosed in the third embodiment as the rotor yoke 121, the iron loss can be extremely reduced.

  By disposing the flywheel disk and its bearings in a low-pressure sealed container, rotational friction loss can be reduced.

100 rotor 110 rotor magnet 120 rotor core 121 rotor yoke 122 rotor teeth 123 rotor slot 200 stator 210 stator iron core 211 stator yoke 212 stator teeth 213 status lot 220 winding coil 300 magnetic ribbon 1000 rotating electrical machine 2000 flywheel disc

Claims (9)

A rotor,
An axial gap rotating electrical machine having a stator disposed opposite to the rotor in the rotation axis direction,
The rotor or the stator has a yoke and teeth,
In the rotational axis direction, the teeth are formed on the yoke,
When viewed from the rotation axis direction, the yoke and the teeth are formed in a spiral shape,
The teeth are trapezoidal when viewed from the direction of the rotation axis. In claim 1,
An axial gap type rotating electrical machine in which the yoke and the teeth are configured by winding a magnetic ribbon having a continuous slit. In any one of Claims 1-2.
In the circumferential direction, a slot is formed between the teeth,
An axial gap type rotating electrical machine in which a circumferential width of the slot is constant in a radial direction. In any one of Claims 1 thru | or 3.
In the rotational axis direction, two of the rotors are arranged across the stator,
The two rotors each have a rotor magnet and a rotor core,
In the circumferential direction, the magnetic poles of the respective rotor magnets are different from each other,
An axial gap type rotating electrical machine in which the two rotor magnets have the same magnetic poles on opposite surfaces in the rotation axis direction. In claim 4,
In the rotational axis direction, the teeth are formed on both sides of the yoke,
An axial gap type rotating electrical machine in which the teeth on both sides are displaced when viewed from the direction of the rotation axis. In any of claims 3 to 5,
An axial gap type rotating electrical machine in which a magnet is formed in the slot in the rotor in a circumferential direction. An axial gap type rotating electrical machine according to any one of claims 1 to 6,
A flywheel power storage device comprising: a flywheel disk attached coaxially to the axial gap type rotating electrical machine. In claim 7,
The flywheel disk is a flywheel power storage device arranged in a sealed container. A rotor,
A stator disposed opposite to the rotor in the direction of the rotation axis, and a manufacturing method of an axial gap rotating electrical machine,
The rotor or the stator has a yoke and teeth,
In the rotational axis direction, the teeth are formed on the yoke,
When viewed from the rotation axis direction, the yoke and the teeth are formed in a spiral shape,
A manufacturing method of an axial gap type rotating electrical machine in which the teeth are trapezoidal when viewed from the rotation axis direction.