JP5879121B2 - Axial gap rotating electric machine - Google Patents

Description

  The present invention relates to a structure of an axial gap 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. Currently, most of the electricity produced in domestic power plants such as thermal power, hydropower, nuclear power, and wind power is produced by rotating electrical machines (generators) that are electromagnetic application products. Further, more than half of the amount of power used in the country is consumed by driving the rotating electrical machine. In these electromagnetic application products such as rotating electrical machines, a soft magnetic material is used for the iron core portion, and reducing the loss of the iron core portion is a means for realizing high efficiency of these products. Another measure to improve efficiency is to use a permanent magnet with a high magnetic force to increase the magnet torque per predetermined current so that the required torque can be obtained at a low current. There is a means for reducing (copper loss).

  Patent Document 1 is cited as a method for improving the efficiency of a permanent magnet motor. In Patent Document 1, an axial gap type motor is used in order to use a low-loss amorphous material for a soft magnetic material used in a permanent magnet motor, and the volume of the permanent magnet is increased in order to reduce copper loss. A motor having a configuration in which the two surfaces are rotors has been proposed. However, this structure is a structure in which the rotor is present on both sides in the axial direction with respect to the stator, so that the stator is disposed in the center in the axial direction. For this reason, the stator and the stator coil wound around the stator are fixed by molding with a resin or the like. Although this fixing method has been put into practical use with a motor with a small capacity, it is difficult to ensure the positioning accuracy of the stator core and the stator coil in the mold of the resin molding, Since the price is high, there are problems such as high price of the motor. In addition, there is a problem in the long-term reliability of the stator holding due to stress applied to the resin due to expansion and contraction due to heat of the stator coil and the iron core.

  As a method for solving the above problem, Patent Document 2 has been proposed. Here, the rotor of the axial gap motor is only one on one side, a back yoke is additionally provided on the stator body, and the back yoke composed of the iron core is used by a method such as shrink fitting or press fitting with the housing. To conclude. However, as for the fixing method of the stator core and the back yoke, the stator core body and the stator coil wound around the stator core, it is desirable to employ a resin mold, as in Patent Document 1, as described above. Problems remain in resin reliability due to thermal expansion and contraction of coils and iron cores.

JP 2010-115069 A JP 2010-051075 A

  In a motor having a structure as disclosed in the above two patent documents, an increase in assembly man-hours by integrating the stator core and the stator coil with resin, a corresponding increase in price due to the addition of resin members, and heat There are problems such as a decrease in reliability due to expansion and contraction.

  An object of the present invention is to provide an axial gap type rotating electrical machine with improved assemblability, low cost, and high reliability.

  In order to solve the above problems, the present invention has a function of holding a stator core of an axial motor and a function of holding a stator coil wound around the stator core while maintaining insulation from the core. A non-conductive and non-magnetic iron core / coil holding member provided is positioned in both the circumferential direction and the axial direction, and a structure that facilitates fixing to the motor housing is proposed.

  Specifically, in an axial gap rotating electrical machine having rotors on both sides in the axial direction, an iron core having a stator core holding function and a coil winding function made of a non-conductive and non-magnetic material. The holding member that holds the coil and the coil has a structure in which a plurality of holding members are arranged in the circumferential direction with an angle equally divided by the number of slots of the stator. Thicken in the opposite direction to the entering side to improve strength, and position the thickened collar part on one side in the axial direction on the stepped part of the motor housing that is held in contact with the outer periphery. It is fixed in the axial direction by adopting a structure in which the axial direction is pressed down and held by a cylindrical ring-shaped holding member having a diameter in contact with the inner diameter of the housing for axially positioning the opposite side surface.

  With the above structure, the stator core around which the coil is wound, the holding member that holds the core and the coil, and the stator coil can be fixed to the housing without being resin-molded. Even if there is contraction, it is considered that there is almost no influence on the fastening portion with the housing. Also, since resin molding is not performed, the assembly (molding) process and resin cost can be reduced, the above problems can be solved, and a motor configuration that can be handled in the same way as a normal motor in appearance is possible. And can.

  According to the present invention, since the stator core around which the coil is wound, the holding member for holding the core and the coil, and the stator coil can be fixed to the housing without resin molding as in the above-mentioned known literature, the temperature of the coil increases. Even when thermal expansion or contraction occurs due to the above, there is almost no influence on the fastening portion with the housing, and since the resin molding is not performed, the assembly (molding) process and the cost of the resin can be reduced.

1 is a perspective view of an iron core / coil holding member 1 having a stator core holding function and a coil holding function of an axial gap motor of the present invention. FIG. It is the perspective view which showed the state which assembled the motor housing in the state which wound the coil around the iron core / coil holding member 1 and held the iron core, including the cross section of the central portion. It is a figure explaining the iron core and coil holding member 1 of this invention, and the holding structure of an iron core. It is a figure which shows the various patterns for the holding strength improvement of the iron core and coil holding member 1 of this invention. It is a figure which shows the structural example of the axial direction fixation in the various patterns for the holding strength improvement of the iron core and coil holding member 1 of this invention. It is a figure which shows the iron core and coil holding member 1 of 2nd Example of this invention with a perspective view. It is the figure which showed the structure of the axial gap motor using the stator using the iron core and coil holding member 1 of this invention with the perspective view. It is a figure which shows the structure of an iron core.

  Embodiments of the present invention will be described below with reference to the drawings.

Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows a perspective view of an iron core / coil holding member (holding member for holding an iron core and a coil) 1 having a stator core holding function and a coil holding function of the axial gap motor of the present invention. The iron core / coil holding member 1 is made of a non-conductive and non-magnetic material. The opening angle θ of the iron core / coil holding member 1 is configured to be an angle obtained by dividing 360 degrees by the number of slots of the stator 100 of the motor (in this case, 40 degrees). The central fan-shaped hole 4 is a through-hole, and a stator core is disposed here. In the circumferential direction of the stator core, the coil is wound around the body 3 of the iron core / coil holding member 1 so that the iron core and the coil are electrically insulated from each other so as not to protrude in the axial direction (up and down direction on the paper surface). 2 and 2 'for holding. In order to increase the strength, a part 6 (thick part) having a part thicker than the coil winding part is provided in a part of the outer peripheral side of the flange part 2 in the circumferential direction. The thick wall portion 6 provided in the flange portion 2 is provided in a portion where the diameter is further larger than the outermost diameter of the flange portion 2 ', and the dimension d is radially outward with respect to the outermost periphery of the flange portion 2'. It is provided so that only _one sticks out. This is because the cross-sectional area of the conductive material (coil) disposed in this region can be increased and the loss from the coil can be reduced as the thickness of the collar or body of the portion around which the coil is wound is usually reduced. is there. In addition, since the rotor is disposed on both sides in the axial direction of the stator 100 via a narrow gap, a structure is projected from both ends in the axial direction of the stator core and the coil wound around the stator core. It is because it is not possible. Moreover, it was set as the structure which provided the notch 8 in the circumferential direction edge part of the collar parts 2 and 2 '. The notch 8 is provided over the entire range in which the body portion 3 is provided in the radial direction. This is a positioning groove for holding a member for interphase insulation between adjacent coils after winding the coil. Further, in FIG. 1, a stepped portion 5 in the axial direction is formed on the flange portion 2 on the inner diameter side. The purpose of this stepped portion 5 is to perform axial positioning of components arranged on the inner peripheral side. It is also necessary to provide at least one notch 7 for drawing out the terminal wire of the coil in a part of at least one of the flange portions 2 and 2 '.

  FIG. 2 shows an axial gap structure motor stator having a 9-slot stator core. FIG. 2 is a perspective view showing a state in which a coil is wound around the iron core / coil holding member 1 shown in FIG. A stator core 11 is disposed in the central through hole of the core / coil holding member 1. A coil 12 is wound around the iron core / coil holding member 1 so as to be electrically insulated from the stator iron core 11. The terminal wire of the wound coil 12 is connected by three coils being continuously wound, and the final ends of the three coils are connected together and connected to the outside of the motor stator 100. Output three terminal lines 13u, 13v, 13w. The iron core / coil holding member 1 holding the coil 12 and the stator core 11 is arranged in contact with the circumferential direction, and nine pieces are positioned in the circumferential direction at 360 degrees. In this state, it is inserted into the motor stator housing 14 by press-fitting and shrink-fitting and fixed, and the axial direction is a stepped structure portion formed by making the end surface of the thick portion 6 of the flange portion 2 different in housing inner diameter. It is structured to be positioned by contact fixing to 14a. In addition, as a structure in which the other end face of the thick part 6 of the thickened collar part 2 is pressed by a collar 15 of a cylindrical ring having an outer diameter for press-fitting into the inner diameter part of the housing, the iron core / coil holding member 1 The structure is fixed in the axial direction.

  In this example, the inner diameter portion is a set of the iron core / coil holding member 1 by combining the stepped portion of the sliding bearing portion 16 with the stepped portion 5 provided on the inner peripheral side of the iron core / coil holding member 1. The configuration is such that the coaxiality between the stator 100 and the bearing portion 16 as a body is guaranteed. Similarly, on the opposite side in the axial direction, a ring-shaped collar 17 that can be combined with the stepped portion 5 provided on the inner peripheral side of the iron core / coil holding member 1 is press-fitted and fixed to the outer peripheral portion of the bearing portion 16. And the stator which is an aggregate | assembly of the iron core and the coil holding member 1 is set as the structure restrained in the circumferential direction and an axial direction.

  Next, the iron core / coil holding member 1 and the iron core holding structure will be described with reference to FIG. FIGS. 3A to 3D are perspective views showing different methods of holding the iron core. First, FIG. 3A shows a method of press-fitting and fixing an iron core to the iron core / coil holding member 1. As shown in the figure, the iron core is inserted into the iron core / coil holding member 1 for assembly. By inserting the iron core to be slightly larger than the through hole 4 of the iron core / coil holding member 1 The stator core can be held by the pressure (friction). In addition, in the case of insertion assembly with a clearance fit tolerance instead of press-fitting, fixing by applying an adhesive or the like is also possible.

  FIG. 3B shows a method in which the stator iron core 11 is inserted into the through hole 4 of the iron core / coil holding member 1 and then taped with an insulating member. In this case, fixing after winding a coil (coil) is considered effective. In this method, the stator core 11 is fixed with a thin insulating tape having a width corresponding to the notch 8 provided in the collar so as to wrap the coil inserted and wound. In this case, since this insulating tape insulates between adjacent coils when the stator 100 is disposed in the circumferential direction, a highly reliable stator can be obtained. It is considered that various materials can be used as the material of the insulating tape, and it is desirable to select a material suitable for the insulation grade, such as PP, PPS, polyimide, Nomex, and aramid paper.

  FIG. 3C is an example in which the same effect as that of the insulating tape shown in FIG. The tape winding described above requires the work of winding one by one, increasing the number of manufacturing steps. For this reason, it is possible to simplify the process by inserting a member such as a heat-shrinkable tube, which has been formed in a size that can be easily inserted in advance, and shrinking it by dryer drying or the like.

  FIG.3 (d) is the method of arrange | positioning the stator core 11 in a metal mold | die, and integrating the core and the coil holding member 1 on the surface by injection molding. Compared to the method shown in FIGS. (A) to (c), it is considered that there are advantages such as easy handling and high strength because it is made into parts. In this case, the coil must be wound after the stator core 11 and the iron core / coil holding member 1 are integrated, and the interphase insulation as described above must be provided separately. I must.

  FIG. 4 shows various patterns for improving the holding strength of the iron core / coil holding member 1. (A) The figure has shown the iron core and coil holding member 1 described so far, and is the example in which the thick part 6 is provided only in one place of the outer peripheral direction collar part. (B) The figure shows an example in which the thick portion 6 is formed in the flange portions 2 and 2 'on both sides in the axial direction. (C) The figure has shown the example in the case of fixing an axial direction firmly also in an inner peripheral direction, and is an example which provided one thick part 6 also in the inner peripheral part. (D) The figure shows the example which has provided the thick part 6 in the inner peripheral side of the collar parts 2 and 2 ', respectively.

  FIG. 5 shows an example of the axially fixed configuration. (A) As shown in FIG. 2, the figure shows a structure in which the thickly configured flange portion 6 is fixed in the axial direction by the stepped structure portion 14 a of the housing 14 and the collar 15. FIG. 4B shows an example in which the thick portions 6 are formed on the flange portions 2 and 2 ′ on both sides in the axial direction, as shown in FIG. The stepped structure 14a and the upper thick portion 6 shown in the drawing are sandwiched between the non-magnetic and non-conductive collars 18, and are further pressed by the cylindrical ring-shaped collar 15 from the lower side in the axial direction. At this time, the collar 18 positioned in the central portion in the axial direction may be made of a material such as ceramics, and has high thermal conductivity for the purpose of transferring Joule heat generated from the coil to the housing 14 in addition to maintaining strength. It is effective to use a material. Further, a method of inserting an adhesive member 16 such as a heat conductive gel and maintaining the axial direction with the rigidity of the iron core / coil holding member 1 is also conceivable.

Subsequently, a second embodiment of the present invention will be described with reference to FIG.
In the first embodiment, an example has been shown in which the flanges 2 and 2 'of the iron core / coil holding member 1 have a thickness, that is, by providing the thick portion 6, the strength of fixing in the axial direction is maintained. In the second embodiment, a method of improving the mechanical strength such as rigidity of the flange portions 2 and 2 'of the iron core / coil holding member 1 by another method and fixing in the axial direction will be described.

  FIG. 6 is a perspective view showing the iron core / coil holding member 1 of the second embodiment. FIG. 6A shows the shape of the metal frame 26 inserted into the iron core / coil holding member 1. The frame 26 has a shape having a portion 26a constituting a collar portion of the outer peripheral portion and a portion 26b constituting a collar portion of a coil winding portion in the radial direction. This material needs to be a non-magnetic metal so as not to block the magnetic flux from the magnet rotor of the axial gap motor. In the case of a conductive metal, if it is configured so as to surround the stator core, an eddy current is generated around it, so it is important that a part in the circumferential direction is not connected. In this example, the inner peripheral side is not connected. Such a consideration is not necessary when it is made of a member such as ceramics. This thickness is desirably about half of the thickness of the collar portion of the iron core / coil holding member 1. This is because if the thickness is too large, the space factor of the coil decreases and the loss increases. A shape in which the frame 26 is insert-molded and integrated with the iron core / coil holding member 1 is shown in FIG. As in the iron core / coil holding member 1 shown in FIG. 1, since the strength is improved by a metal frame (framework) without increasing the thickness of the collar portion, it is possible to fix it with the thickness as it is. . The surface on which the coil is wound is made of an insulating material (resin), and has a structure in which a metal skeleton for improving the strength is exposed on the surface in other portions. There is no problem even if the structure is completely embedded in the resin.

  The frame portions 26a and 26b may be provided on either one of the flange portions 2 and 2 ', or may be provided on both.

  FIG. 6B shows an example of a metal skeleton (frame 27) whose strength is improved also in the axial direction. The frame 27 has portions 27a and 27b that constitute a part of the flanges 2 and 2 ', similarly to the parts 26a and 26b that constitute a part of the flanges 2 and 2' in FIG. However, the frame portion 27c is also formed in the axial direction to increase the strength of the upper and lower flange portions 2, 2 '. The iron core / coil holding member 1 incorporating this is shown in FIG. As a result, the flanges 2 and 2 ′ on both sides in the axial direction and the strength for supporting them can be improved, so that the axial direction can be fixed by the method shown in FIG.

  FIG. 6 (e) shows an iron core / coil holding member 1 obtained by adding strength to a resin containing GF (glass fiber) such as carbon fiber, aramid fiber, nanofiller or core-shell type particles in the resin. . As a result, the holding strength can be improved by improving the strength by the thickness of the flange portions 2 and 2 'and by improving the original strength of the resin.

  In addition to the above, the iron core / coil holding member 1 may be configured by coating a metal holding member with a non-conductive member.

Subsequently, a third embodiment of the present invention will be described with reference to FIG.
FIG. 7 is a perspective view showing a configuration of an axial gap motor using the stator 100 using the iron core / coil holding member 1 described so far. Rotors 200a and 200b each including a rotor yoke 31, a permanent magnet 32 attached thereto, and a spacer 33 between permanent magnets are provided on both sides in the axial direction with respect to the stator 100 shown in FIG. . Two rotors 200 a and 200 b provided on both sides in the axial direction with respect to the stator 100 are connected via a shaft 34, and are configured to be rotatable with respect to the stator 100 by a sliding bearing 16. The rotors 200a and 200b generate torque by a coil current and operate as a motor. The stator 100 receives a rotational force due to the reaction force of the torque, and an axial force is applied by the attractive force of the magnet. As described above, it is necessary to fix these forces in the axial direction and in the rotational direction, and a structure that sufficiently fixes the flanges 2 and 2 ′ of the iron core / coil holding member 1. It has become.

  In FIG. 8, it shows about the Example from which the structure of an iron core differs. (A) The figure shows the iron core in which a magnetic steel sheet or iron core with a structure in which foil strips of iron-based amorphous, finemet, nanocrystal materials, etc. are laminated in the circumferential direction is formed in a fan shape. In this case, the iron core / coil holding member 1 of the present invention is effective. FIG. 4B shows an example in which an iron core obtained by compression molding powder such as a dust core and ferrite is used. (C) The figure has shown the example which comprises such an iron core which shows the iron core of the structure which laminated | stacked foil strips, such as an electromagnetic steel plate or iron-based amorphous | non-crystalline amorphous, fine met, and nanocrystal material, in the circumferential direction as a rectangular cross section. . (D) The figure shows the iron core which provided directionality to the iron core of the soft magnetic material shown in the (a) figure to the (c) figure. In the axial gap motor of the present invention, since the magnetic flux flows only in the axial direction, an anisotropy is provided in this direction.

  The motor of the axial type structure of the present invention can be applied to a wide range of motors aimed at small size, high efficiency and low noise. Further, the system using the motor structure of the present invention can be reduced in size and efficiency, and a general rotating machine system such as a fan, a pump system, a motor for home appliances, a driving of automobile auxiliary machinery, a small wind power generation, etc. It can be widely applied to.

DESCRIPTION OF SYMBOLS 1 Iron core / coil holding member 2 Gutter part 3 Body part 4 Stator iron core holding through-hole 5 Inner peripheral side stepped part 6 Outer peripheral side thick structure collar part 7 Coil terminal pull-out notch part 8 Interphase insulator positioning cut Notch portion 11 Stator iron core 12 Stator coils 13u, 13v, 13w Coil end wire 14 Motor stator housing 15 Stator axial holding collar 16 Bearing portion 17 Bearing portion fixing collar 18 Axial central portion collar 21 Insulating tape 22 Heat shrinkable member 23 Injection mold 24 Iron core / coil holding member molding cavity 25 Resin injection spool 26 Plate frame 27 Axial strength improvement frame 31 Rotor yoke 32 Permanent magnet 33 Intermagnet spacer 34 Shaft

Claims (5)

  Two rotors,
  A stator sandwiched between the two rotors;
  A housing for housing the two rotors and the stator,
  The stator includes a stator core, a holding member that holds the stator core and is made of a non-conductive and non-magnetic material, a coil wound around the holding member, and a flange portion of the holding member A metal frame fixed to the
  The housing forms a step in the inner periphery,
  The holding member is an axial gap rotating electrical machine that is fixed to the inner peripheral portion of the housing so that the flange portion of the holding member faces the step in a state where the frame sandwiches the frame. In the axial gap rotating electrical machine according to claim 1,
The flange has a first flange facing the step and a second flange not facing the step,
An axial gap rotating electrical machine in which the frame includes a first frame portion facing the first flange portion and a second frame portion facing the second flange portion. In the axial gap rotating electrical machine according to claim 1 or 2,
The holding member has a body portion that houses the stator core;
The axial gap rotating electric machine, wherein the frame has a third frame portion facing the body portion. In the axial gap rotating electrical machine according to claim 2,
An axial gap rotating electrical machine characterized in that the interphase insulation in the circumferential direction is achieved by fixing the holding member, the stator core and the coil with an insulating tape. In the axial gap rotating electrical machine according to claim 2,
An axial gap rotating electrical machine, wherein the holding member, the stator core, and the coil are fixed by a heat shrinkable member so as to achieve interphase insulation in the circumferential direction.