Stator core installation structure for axial gap motor

Abstract

The present invention provides a stator core installation structure for an axial gap motor, in which the stator core can be accurately positioned and installed without adding a configuration having an adverse effect on a magnetic circuit to the stator core. An annular stator core (10) is composed of six arc-shaped divided stator teeth (12), and the outer peripheral surface (12a) and the inner peripheral surface (12b) of each divided stator tooth (12) are provided with tapered portions (13, 15) which widen toward the rotor side in accordance with the spacing between the outer peripheral wall portion (16a) and the inner peripheral wall portion (16b) of a stator plate (16). The loading of each divided stator tooth (12) into the stator plate (16) is performed in a state in which the tapered portions (13, 15) are joined by joining members (18, 20, 22) fixed to the stator plate (16).

Description

Technical Field

[0001] The present invention relates to a stator core arrangement structure for an axial gap motor, and more particularly to a stator core arrangement structure for an axial gap motor composed of a plurality of blocks. Background Art

[0002] In recent years, as a substitute for the existing radial gap motor, the use of axial gap motors that can achieve lightness, thickness and high power has become more and more widespread. The axial gap motor has the following structure: a circular stator core and a rotor that rotates coaxially with the axis of the stator core face each other on one or both sides of the axial direction.

[0003] The stator core of the axial gap motor sometimes uses a powder core made by filling a mold with soft magnetic powder and pressing it, instead of the electronic steel sheet used in the radial gap motor. The use of a powder core can increase the degree of freedom of shape and form a good three-dimensional magnetic circuit.

[0004] Fig.11 FIG. 2 shows the stator core disclosed in Patent Document 1. Fig.11 As shown, the stator core 30 is formed by arranging stator teeth 32 divided into a plurality of pieces (six pieces in this example) in a circular ring shape. A hole 38 is formed in the center of the stator core 30, through which the rotor shaft is inserted. Two teeth 34 are protruding on the rotor side of one divided stator tooth 32. The divided stator teeth 32 are fixed to the housing, but the fixing is performed using through holes 36 formed in each divided stator tooth 32, and fixing members such as screws are used in the through holes 36.

[0005] In the axial gap motor, a coil is wound around each tooth portion 34 , and magnetic poles are formed on the surface of the tooth portion 34 . The rotor can rotate according to the polarity of the magnetic poles and the magnets arranged on the rotor.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: WO2020 / 059517 Summary of the invention

[0009] Problems to be solved by the invention

[0010] In the stator core 30 disclosed in Patent Document 1, as described above, the divided stator teeth 32 are fixed to the cover portion of the housing or the stator plate by passing screws through the through holes 36. However, there is a problem that the through holes 36 are not suitable for forming the stator core 30 in consideration of the influence on the magnetic circuit, and in order to reduce the influence of the through holes 36, the size of the stator core 30 needs to be increased or the stator core needs to be complicated.

[0011] In addition, as described above, the segmented stator teeth 32 are powder cores produced by a process of filling a mold with soft magnetic powder and performing pressure molding. Therefore, holes for screw fastening are formed on the segmented stator teeth 32. The screw connection has problems in terms of strength and durability of the segmented stator teeth due to the brittleness of the material. There is also a problem of an increase in the number of manufacturing and assembly steps.

[0012] In addition, in the axial gap motor, the positional relationship between the teeth of the stator core and the magnets of the rotor is more important. Therefore, it is critical to accurately position the stator core on the stator plate for fixing. However, it is difficult to accurately position the stator core by screwing. For example, when making screw holes on the stator plate for fixing the divided stator teeth with screws, if the position is offset, it is impossible to accurately position them immediately. Therefore, the inability to accurately position will also cause the problem of not being able to maximize the performance of the axial gap motor.

[0013] The present invention is completed in view of the above-mentioned problems, and its purpose is to provide a stator core setting structure for an axial gap motor, in which there is no need to add a structure that has an adverse effect on the magnetic circuit to the stator core, and the stator core can be accurately positioned to be set.

[0014] Means of solving problems

[0015] In order to achieve the above-mentioned object, a stator core setting structure for an axial gap motor according to an embodiment of the present invention is characterized in that it comprises: a ring-shaped stator core, which is formed by combining the teeth divided into a plurality of pieces into a ring shape so that the central portion has a hole portion; and a ring-shaped stator plate, which has an outer peripheral wall portion and an inner peripheral wall portion at the outer peripheral edge and the inner peripheral edge respectively, the ring-shaped stator core has a pair of stators filled between the outer peripheral wall portion and the inner peripheral wall portion of the stator plate, and a stator core with the holes is provided between the pair of stators. The center of the hole portion is a rotor rotating about an axis. In the stator core setting structure for the axial gap motor, the annular stator core is composed of a plurality of arc-shaped segmented stator teeth, and a tapered portion is provided on the outer circumferential surface and the inner circumferential surface of each segmented stator tooth, which is widened toward the rotor side corresponding to the separation interval between the outer circumferential wall portion and the inner circumferential wall portion of the stator plate. The loading of each segmented stator tooth into the stator plate is carried out in the following state: each tapered portion is joined by a joining component fixed to the stator plate.

[0016] With this structure, the outer circumferential surface and the inner circumferential surface of each segmented stator tooth are respectively provided with a conical portion, and a state in which the coupling component abuts against the conical portion can be obtained, thereby limiting the movement of the stator core. That is, the conical portion is inclined in a form in which the interval between the outer circumferential wall portion and the inner circumferential wall portion of the stator plate widens toward the rotor side, and each segmented stator tooth is coupled through the conical portion using the coupling component that is in a state of being fixed to the stator plate. This coupling can be simply performed, for example, by the abutment of the coupling component and the conical portion, and the movement of each segmented stator tooth toward the rotor side is limited by the abutment. In addition, regarding the coupling of the coupling component and the conical portion, as long as it is the area where the conical portion is located, there is no need to precisely set its coupling position, and it is also relatively easy to ensure the abutment state of the coupling component against the conical portion.

[0017] Thus, it is not necessary to provide a through hole for fixing in the stator core, so the characteristics of the magnetic circuit are not hindered. In addition, more joints can be fully obtained to fix the stator core more firmly.

[0018] Effects of the Invention

[0019] The stator core arrangement structure for the axial gap motor of the present invention can accurately position the stator core on the stator plate while fixing the stator core without adding a structure that hinders the function. In addition, the use of pressed powder for the stator core can solve the strength and durability problems at the same time, thereby achieving high performance of the axial gap motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a perspective view of one embodiment of the installation structure of the stator core for the axial gap motor of the present invention;

[0021] Figure 2 yes Figure 1 Floor plan of

[0022] Figure 3 yes Figure 2 AA section view;

[0023] Figure 4 yes Figure 3 A partial enlarged cross-sectional view of

[0024] Figure 5 express Figure 1 A perspective view of the divided stator teeth of the stator core shown;

[0025] Figure 6 express Figure 1 A perspective view of the stator plate shown;

[0026] Figure 7 express Figure 6 A CC cross-sectional view of the stator plate shown;

[0027] Figure 8 express Figure 5 BB section view of the split stator teeth shown;

[0028] Fig. 9 express Figure 1 A three-dimensional view of the arc-shaped connecting metal member shown;

[0029] Fig.10 express Fig. 9 DD sectional view of the arc-shaped connecting metal part shown;

[0030] Fig.11 This is an explanatory diagram of the stator core of Patent Document 1.

[0031] Explanation of symbols

[0032] 10 stator core

[0033] 12-part stator teeth

[0034] 12a Outer surface

[0035] 12b Inner Surface

[0036] 13, 15, 19 cones

[0037] 14 teeth

[0038] 16 stator plate

[0039] 16a Outer peripheral wall

[0040] 16b Inner wall

[0041] 16c concave part

[0042] 16e connection screw hole

[0043] 16f connection bolt hole

[0044] 18 Arc-shaped connecting metal parts

[0045] 18a Bolt through hole

[0046] 18b inner surface

[0047] 18c outer surface

[0048] 20 Connecting bolts

[0049] 22 Connecting screws

[0050] 28 Rotating shaft hole

[0051] 30 Stator core of Patent Document 1

[0052] 32-part stator teeth

[0053] 34 teeth

[0054] 36 through holes

[0055] 38 rotating shaft hole. DETAILED DESCRIPTION

[0056] Hereinafter, an embodiment of the arrangement structure of the stator core for an axial gap motor according to the present invention will be described with reference to the accompanying drawings.

[0057] Figure 1 1 is a perspective view of a state where the stator core 10 for the axial gap motor according to the present embodiment is mounted on the stator plate 16; Figure 2 is its floor plan; Figure 3 yes Figure 2 AA section view in the plan view. Figure 4 yes Figure 3 The stator core 10 is formed into an annular shape by six divided stator teeth 12 described later, and is mounted on a stator plate 16 also formed into an annular shape by a coupling member described later.

[0058] As shown in the figure, in this embodiment, the annular stator core 10 is formed by six divided stator teeth 12 . Figure 5 The stator tooth 12 is shown in FIG. 1 , each of which is formed into an arc shape in plan view, and has three teeth 14 on the upper surface. The divided stator teeth 12 are formed by filling a mold with soft magnetic powder and performing pressure molding, and a coil is wound around each tooth 14 and a voltage is applied to form a magnetic circuit.

[0059] A hole 28 is secured in the center of the stator core 10 in which the divided stator teeth 12 are combined in an annular shape. The rotation axis of the rotor is located at the center of the hole 28 . The rotor (not shown) is arranged to face the stator core 10 .

[0060] Figure 6 is a perspective view of the stator plate 16; Figure 7 1 is a CC cross-sectional view thereof. The stator core 10 is fixed to the stator plate 16. As shown in the figure, the stator plate 16 is formed in an annular shape and is made of a non-magnetic material such as aluminum. In addition, an outer peripheral wall portion 16a and an inner peripheral wall portion 16b are formed on the outer peripheral edge and the inner peripheral edge thereof, respectively, and a recess 16c for placing the divided stator teeth 12 is formed between these wall portions.

[0061] Figure 8 yes Figure 5In the BB cross-sectional view of the split stator tooth 12 shown in FIG. 1 , a tapered portion 13 is provided on the outermost circumference, i.e., the outer peripheral surface 12a, of one split stator tooth 12. The slope (angle α°) of the tapered portion 13 is such that the interval between the tapered portion 13 and the outer peripheral wall 16a of the opposite stator plate 16 becomes wider toward the oppositely arranged rotor side (in the figure, the slope becomes wider temporarily upward). In addition, the tapered portion 15 is provided on the innermost circumference, i.e., the inner peripheral surface 12b of the split stator tooth 12, and the slope (angle β°) of the tapered portion 15 is also such that the interval between the tapered portion 13 and the inner peripheral wall 16b of the opposite stator plate 16 becomes wider toward the oppositely arranged rotor side (in the figure, the slope becomes wider temporarily upward).

[0062] Next, the operation of installing each divided stator tooth 12 into the recess 16c of the stator plate 16 using a joining member will be described. Figure 1 , Figure 3 and Figure 4 The connection screw 22 shown. The outer peripheral side is connected using Figure 1 , Figure 3 and Figure 4 The connecting metal part 18, the connecting bolt 20 and the connecting screw 22 are shown.

[0063] First, the segmented stator teeth 12 are loaded into the recessed portion 16c of the stator plate 16, and the tapered portion 15 of the loaded segmented stator teeth 12 abuts against the front end of the coupling screw 22, thereby performing the inner peripheral side engagement. The coupling screw 22 is screwed into the coupling screw hole 16e formed on the inner peripheral wall portion 16b of the stator plate 16, and its front end abuts against the tapered portion 15. The coupling screw 22 abuts against the tapered portion 15, so that the segmented stator teeth 12 are in contact with each other. Figure 4 Movement upward in the graph is restricted.

[0064] That is, the connection structure can be formed by simply forming the connection screw hole 16e through which the connection screw 22 passes on the inner peripheral wall portion 16b of the stator plate 16. Then, the connection screw 22 is passed through the portion of the inner peripheral wall portion 16b opposite to the tapered portion 13 of the divided stator tooth 12 and the tip thereof directly contacts the tapered portion 15, thereby restricting the movement of each divided stator tooth 12 toward the rotor side, thereby obtaining a stable setting state.

[0065] Next, the joining of the outer peripheral side will be described. First, the coupling metal fitting 18 as an intermediate member is fitted into the gap between the outer peripheral surface 12 a of each divided stator tooth 12 and the outer peripheral wall portion 16 a of the stator plate 16 .

[0066] Fig. 9 2. It shows the composition of the connecting metal member 18; Fig.10 express Fig. 9DD sectional view of the arc-shaped connecting metal member shown. The connecting metal member 18 is made of non-magnetic material such as aluminum. As shown in the figure, the gap between the outer peripheral wall portion 16a of the stator plate 16 and the outer peripheral surface 12a of the divided stator tooth 12 is arc-shaped in a plan view, so it is formed into an arc shape suitable for this shape. Moreover, it is important that the inner peripheral surface 18c of the connecting metal member 18 is provided with a taper 19. The slope of the taper 19 is set so that when the connecting metal member 18 is embedded in the gap between the outer peripheral wall portion 16a of the stator plate 16 and the outer peripheral surface 12a of the divided stator tooth 12, it is closely attached to and abutted against the taper 13 of the outer peripheral surface 12a of the divided stator tooth 12. That is, the slope (angle γ°) of the taper 19 is configured to be approximately equal to the slope (angle α°) of the taper 15 of the outer peripheral surface 12a of the divided stator tooth 12.

[0067] The screw member, that is, the coupling bolt 20 is screwed into the stator plate 16 and fixed through the coupling metal member 18, thereby ensuring that the abutment state between the coupling metal member 18 and the tapered portion 13 of the segmented stator tooth 12 is in a stable state. Therefore, the screwing direction of the coupling bolt 20 into the stator plate 16 can be different from the direction of abutment with the tapered portion by the coupling metal member 18, and the application of the coupling structure using the coupling bolt 20 is more diverse. The coupling structure using the coupling metal member 18 can also firmly restrict the movement of each segmented stator tooth 12 toward the rotor side.

[0068] As described above, according to the arrangement structure of the stator core 10 for the axial gap motor of the present embodiment, the tapered portions 13 and 15 are provided on the outer circumferential surface 12a and the inner circumferential surface 12b of the divided stator tooth 12, and the spacing between the tapered portions 13 and 15 and the outer circumferential wall portion 16a and the inner circumferential wall portion 16b of the stator plate 16, respectively, becomes wider toward the rotor side. Therefore, the outer circumferential surface 12a of the divided stator tooth 12 abuts against the fastening metal fitting 18 as an intermediate member fixed to the stator plate 16 by the fastening bolt 20, and the inner circumferential surface 12b of the divided stator tooth 12 abuts against the tip of the fastening screw 22 also fixed to the stator plate 16, thereby obtaining a stable fixed state.

[0069] Therefore, although the stator plate 16 has a through hole or a recess for mounting the coupling component, no additional structure is generated in the stator core 10 itself. In this state, the coupling component is in direct or indirect contact with the tapered portions 13 and 15 of the segmented stator teeth 12, thereby restricting the movement of each segmented stator tooth 12 toward the rotor side, thereby avoiding the disadvantage of performance degradation caused by adverse effects on the magnetic circuit.

[0070] Furthermore, the stator core 10 can be accurately positioned and fixed to the stator plate 16 without adding a structure that hinders the function to the stator core 10. This also makes it possible to achieve higher performance of the axial gap motor.

[0071] It should be noted that the present invention is not limited to the above-mentioned embodiments, and various modifications can be made without departing from the scope of the present invention. For example, the number of divided stator teeth 12 is 6, but it can also be applied to situations where the number is other than 6.

Claims

1. A stator core arrangement structure for an axial gap motor, characterized in that: The invention comprises: a ring-shaped stator core, which combines teeth divided into a plurality of pieces into a ring shape so that a hole portion is provided in the center; and a ring-shaped stator plate, which has an outer peripheral wall portion and an inner peripheral wall portion at the outer peripheral edge and the inner peripheral edge respectively, the ring-shaped stator core has a pair of stators filled between the outer peripheral wall portion and the inner peripheral wall portion of the stator plate, and a rotor rotating about the center of the hole portion as an axis is provided between the pair of stators. In the arrangement structure of the stator core for the axial gap motor, The annular stator core is composed of a plurality of arc-shaped segmented stator teeth, and a tapered portion is provided on the outer circumferential surface and the inner circumferential surface of each segmented stator tooth, and the tapered portion widens toward the rotor side corresponding to the separation interval between the outer circumferential wall portion and the inner circumferential wall portion of the stator plate. The stator plate is loaded with each of the divided stator teeth in a state where each of the tapered portions is joined by a joining member fixed to the stator plate.

2. The stator core arrangement structure for an axial gap motor according to claim 1, characterized in that: The engagement structure of the divided stator teeth using the engagement member is constituted by a coupling member, and the coupling member is in a state of directly or indirectly contacting the tapered portion of the divided stator teeth in a state of being coupled to the stator plate.

3. The stator core arrangement structure for an axial gap motor according to claim 2, characterized in that: The engagement structure of the divided stator teeth using the coupling member is constituted by a screw member which penetrates the inner peripheral wall portion of the stator plate from the outside thereof and has its tip abutting against the tapered portion of the divided stator teeth.

4. The stator core arrangement structure for an axial gap motor according to claim 2, characterized in that: The engagement structure of the split stator teeth using the coupling component is composed of an intermediate component and a screw component, wherein the intermediate component is arranged between the outer peripheral wall portion of the stator plate and the tapered portion of the split stator teeth and abuts against the tapered portion, and the screw component penetrates the intermediate component and is screwed into the stator plate.

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