Motor

Abstract

To increase the assembly performance and increase the circularity of a stator.SOLUTION: The present invention includes a rotor and a stator. The stator has a plurality of segments connected together via an engagement unit. The segments have a plurality of pieces connected together via a connecting part. The pieces are arranged in an arc and the segments are arranged in a circle. The engagement unit has two protruding parts protruding in a circumferential direction and a recessed part between the two protruding parts. The protruding part of one of two segments arranged adjacent to each other is engaged with the recessed part of the other segment, and the recessed part of the one segment is engaged with the protruding part of the other segment. The two protruding parts of the segments each have a top part, and the protruding part of the one segment and the recessed part of the other segment have a first flat surface and a third flat surface facing each other. The first flat surface and the third flat surface extend in a radial direction and in a circumferential direction of the stator, and also extend in directions perpendicular to each other to the top part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a motor. [Background technology]

[0002] Conventionally, a motor has been known in which a plurality of segment-shaped steel plates are stacked in the thickness direction to form segments, and a stator is formed by assembling the plurality of segments into an annular shape, and then combining this stator with a rotor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2000-152529 A Summary of the Invention [Problem to be solved by the invention]

[0004] In conventional stators, a segment shape in which multiple pieces are connected is punched out of a steel plate, the punched steel plate is stacked, and then bent inward to form a fan-shaped segment. The fan-shaped segments are then assembled into a ring to form a stator. However, when multiple segments are assembled into a ring, the engaging parts are engaged so that they simply come into contact with each other. This results in insufficient engagement between the engaging parts of the segments. As a result, the segments move outward or inward around the engaging parts, which deteriorates the circularity of the multiple segments when assembled into a ring, and if the assembled position of the segments is shifted, it becomes difficult to assemble them into the housing.

[0005] The present invention addresses the above-mentioned problem as an example, and has as its object to improve the roundness of a stator. [Means for solving the problem]

[0006] A motor according to one aspect of the present invention includes a rotor and a stator. The stator is connected to the rotor via an engagement portion. odd number The segment includes a plurality of pieces connected via a connecting portion. The plurality of pieces are arranged in an arc shape, and the odd number The segments are arranged in a ring shape. Odd number of segments The engagement part is each , Shuhou Towards Two protruding protrusions, In the radial direction and a recess provided between the two protruding portions. Of two adjacently arranged segments, the protruding portion of one segment engages with the recessed portion of the other segment, and the recessed portion of the one segment engages with the protruding portion of the other segment. Segments The two protruding portions of the one segment and the other segment have apexes, and the protruding portion of the one segment and the recessed portion of the other segment have first and third planes that face each other. The first and third planes extend in the radial and circumferential directions of the stator and extend in directions that intersect each other toward the apexes. The tops of the protruding portions of the one segment and the other segment protrude toward the inner periphery of the stator. The recessed portion of the one segment and the protruding portion of the other segment have a second plane and the third plane that face each other. The second plane and the third plane extend in the radial and circumferential directions of the stator and extend in directions that intersect with each other toward the tops. The first plane and the second plane form an acute angle with a line along the circumferential direction perpendicular to a center line along the radial direction of the stator, and the third plane forms a positive angle with a line along the circumferential direction perpendicular to the center line along the radial direction of the stator. The contactable area of ​​the second plane is larger than the contactable area of ​​the first plane.

[0007] According to one aspect of the present invention, the roundness of the stator can be improved. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a configuration example of a stator according to the present embodiment. [Diagram 2] FIG. 2 is a perspective view showing an example of the shape of a segment. [Diagram 3] FIG. 3 is a plan view showing an example of the shape of a segment. [Figure 4] FIG. 4 is a plan view showing an example of a joint portion of segments before being folded. [Diagram 5] FIG. 5 is an explanatory diagram for setting the shape of the connecting portion of the segments. [Figure 6] FIG. 6 is an explanatory diagram for setting the shape of the connecting portion of the segments. [Figure 7]FIG. 7 is a plan view showing an example of a stator in which a plurality of segments are assembled. [Figure 8] FIG. 8 is a plan view showing an example of a joint portion of the segments after bending. [Figure 9] FIG. 9 is a plan view showing an example of an engaging portion of the segments after assembly. [Figure 10] FIG. 10 is an explanatory diagram for setting the shape of the engaging portion of the segments. [Figure 11] FIG. 11 is a plan view showing an example of a stator in which a plurality of segments are assembled. [Figure 12] FIG. 12 is a perspective view showing a plurality of segments before being assembled. [Figure 13] FIG. 13 is a perspective view showing the assembled plurality of segments. [Figure 14] FIG. 14 is a perspective view showing a configuration example of a motor. [Figure 15] FIG. 15 is a perspective view showing an example of the configuration of a motor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, motors according to embodiments will be described with reference to the drawings. Note that the present invention is not limited to these embodiments. Furthermore, the dimensional relationships and ratios of elements in the drawings may differ from the reality. The drawings may also include parts with different dimensional relationships and ratios. Furthermore, the contents described in one embodiment or modified example are, in principle, applicable to other embodiments or modified examples in the same manner.

[0010] FIG. 1 is a perspective view showing a configuration example of a stator 2 according to this embodiment. In FIG. 1, a stator 21 and an annular substrate (hereinafter referred to as a connection plate) 28 provided on the stator 21 are shown. The stator 21 is formed into an annular shape by a plurality of (for example, three) segments 23, in which a plurality of (for example, two) pieces are connected via a bendable connection part, an upper insulator 24 and a lower insulator 25 are attached to each piece of the segments 23, a coil 26 is wound around each piece, and the connection part is bent. Here, the insulator is composed of the upper insulator 24 and the lower insulator 25. Each of the segments 23 forms a core of the stator as a whole as a segment. When three segments 23 are used, the number of segments is three. The number of segments is preferably three in order to increase rigidity against the second and fourth circular vibration modes, but may be an odd number of three or more. Furthermore, the number of pieces included in the multiple segments 23 may be an even number, and the number of the multiple segments 23 may be an odd number or a prime number. Even if the number of pieces is an even number, by making the number of segments 23 an odd number or a prime number that is 3 or greater, it is possible to suppress motor vibrations and noise associated with the vibrations.

[0011] The connection plate 28 collectively wires the terminals 27 provided on the upper part of the upper insulator 24 for each piece (slot) of the segment 23, and is formed of a printed circuit board or a predetermined board provided with a printed circuit board and a mutual junction conductor (bus bar). The connection plate 28 may be connected to the terminals 27 after the segment 23, which is wound with the coils 26 and temporarily assembled into an annular shape, is inserted into the housing of the motor. The electrical connection of the coils 26 in each slot is performed collectively by the connection plate 28 via the terminals 27, so that the jumper wires do not cross. In addition, a guide portion for guiding the jumper wires in the insulator is not required, and the dimension of the stator in the rotation axis direction can be shortened and the dead space of the motor can be reduced. In the illustrated example, the end portions 27-a of the terminals 27 are inserted into the multiple holes 28a formed in the connection plate 28, and a part of the end portion 27-a of the terminals 27 protrudes outward from the surface of the connection plate 28. An end 27-a of the terminal 27 is electrically connected to a part of the wiring formed on the connection plate 28. Protrusions 27-b and 27-c that are fixed to the insulator are connected to the end 27-a.

[0012] Fig. 2 is a perspective view showing an example of the shape of a segment, and Fig. 3 is a plan view showing an example of the shape of a segment. In Fig. 2 and Fig. 3, a steel plate 22 is formed by punching out an electromagnetic steel plate using a die or the like. A plurality of steel plates 22 are stacked to form a segment 23.

[0013] The segment 23 is formed by stacking a plurality of steel plates 22 as magnetic bodies. In FIG. 2, the end faces that appear due to the stacking of the electromagnetic steel plates are omitted. In the illustrated example, two pieces 23a having a substantially T-shaped planar shape are connected via a connecting portion 23b. Teeth 23e are formed on each piece 23a. One end 23e1 of the teeth 23e (the end facing the rotor 3 in the radial direction) becomes a magnetic pole portion. The connecting portion 23b is formed with a first recess 23b-a recessed toward the outer periphery on the inner periphery side. Also, the connecting portion 23b is formed with a second recess 23b-b recessed toward the inner periphery on the outer periphery side. The first recess 23b-a is formed in an arc shape, and the second recess 23b-b is formed in a rectangular shape. The connecting portion 23b is formed so that the portion between the first recess 23b-a and the second recess 23b-b is narrow, and the first recess 23b-a can be easily bent in a direction in which it closes.

[0014] A pair of opposing surfaces 23b-c is provided from the first recess 23b-a toward the inner periphery. The pair of opposing surfaces 23b-c is connected to the pair of opposing parts 23b-d. The pair of opposing parts 23b-d is located on the inner periphery side of the connecting part 23b. That is, the segment 23 is provided with a pair of protruding parts 23f protruding toward the inner periphery side between each piece 23a and the connecting part 23b. The pair of opposing surfaces 23b-c and the pair of opposing parts 23b-d are located opposite to each other at the pair of protruding parts 23f. The pair of opposing surfaces 23b-c is a flat surface, and the pair of opposing parts 23b-d is an opposing line (design contact line) along the rotation axis direction of the motor 1. When the segment 23 is folded, the pair of opposing surfaces 23b-c approach each other and a gap is secured between them. At this time, the pair of opposing parts 23b-d contact each other or a minute gap is provided between them. That is, the pair of opposing parts 23b-d are in contact with each other or have a small gap therebetween depending on the tolerance or error. The pair of surfaces 23b-e are provided on the inner circumferential side of the pair of opposing parts 23b-d and are set in an area outside the pair of opposing surfaces 23b-c. That is, the pair of surfaces 23b-e are provided on the tip side of the pair of protruding parts 23f.

[0015] The segment 23 has engagement parts 23c, 23d at the left and right ends, and when folded into a ring shape, they come into contact with and engage with the engagement parts 23c, 23d of the adjacent segment 23. One of the engagement parts 23c has two protruding parts 23c-a, 23c-b protruding to one side in the circumferential direction, and a recessed part 23c-c provided between the two protruding parts 23c-a, 23c-b. The other engagement part 23d has two protruding parts 23d-a, 23d-b protruding to one side in the circumferential direction, and a recessed part 23d-c provided between the two protruding parts 23d-a, 23d-b.

[0016] Of the two adjacent segments 23, the convex portion 23c-a of one segment 23 engages with the concave portion 23d-c of the other segment 23, and the concave portion 23c-c of one segment engages with the convex portion 23d-b of the other segment 23. The convex portion 23c-a of one segment 23 has an apex 23c-d, and the convex portion 23d-b of the other segment 23 has an apex 23d-d.

[0017] The protruding portion 23c-a of one segment 23 and the recessed portion 23d-c of the other segment 23 have first planes 23c-e, 23d-e facing each other. The first planes 23c-e, 23d-e extend in the radial and circumferential directions of the stator 2 and extend in directions intersecting each other toward the apex 23c-d. The recessed portion 23c-c of one segment 23 and the protruding portion 23d-b of the other segment 23 have two second planes 23c-h, 23d-h facing each other. The second planes 23c-h, 23d-h extend in the radial and circumferential directions of the stator 2 and extend in directions intersecting each other toward the apex 23d-d. Here, the first plane 23c-f and the second plane 23c-g are the same plane. In addition, in the engagement portion 23d, the first plane 23d-f and the second plane 23d-g are the same plane. The third planes 23c-f and 23c-g shared by the convex portion 23c-a of one segment 23 and the concave portion 23d-c of the other segment 23, and shared by the concave portion 23c-c of one segment 23 and the convex portion 23d-b of the other segment 23, are the same plane.

[0018] In addition, in the linear state shown in Figures 2 and 3, the surface 23a-1 of the connecting portion 23b, the surface 23c-1 of the engaging portion 23c, and the surface 23d-1 of the engaging portion 23d are located at the same position in the vertical direction in Figure 3 and are arranged on a straight line. In this state, the surface 23c-2 of the engaging portion 23c and the surface 23d-2 of the engaging portion 23d are parallel, and the surface 23a-1 of the connecting portion 23b is perpendicular to the surfaces 23c-2 and 23d-2. The surfaces 23a-1, 23c-1, 23c-2, 23d-1, and 23d-2 serve as positioning surfaces when winding the coil 26 around the segment 23 and when mounting the segment 23 on a device.

[0019] The shapes of the pair of opposing surfaces 23b-c and the pair of opposing portions 23b-d in the connecting portion 23b will be described in detail below. FIG. 4 is a plan view showing an example of the connecting portion of the segments before bending, FIG. 5 is an explanatory diagram for setting the shape of the connecting portion of the segments, and FIG. 6 is an explanatory diagram for setting the shape of the connecting portion of the segments. In FIG. 4 to FIG. 6, the connecting portion 23b has a first recess 23b-a formed on the inner periphery side and a second recess 23b-b formed on the outer periphery side, so that the radial width is narrowed. The first recess 23b-a is an arc with a center O1 and has an arc shape, but may be, for example, an ellipse.

[0020] The connecting portion 23b has a design center O2, which is the center of bending rotation of the two adjacent pieces 23a. The design center O2 is preferably located at the middle position between the two adjacent pieces 23a and at the middle position between the first recess 23b-a and the second recess 23b-b. In addition, the connecting portion 23b has a virtual point O3 for determining the shape of the two adjacent pieces 23a. The virtual point O3 is set on the outer periphery side in the radial direction from the design center O2. The design center O2 and the virtual point O3 are located on a bending line L1 that passes through the center of the stator 2 and runs along the radial direction. The center O1 of the first recess 23b-a is also located on the bending line L1.

[0021] First, a first virtual circle C1 is set that is centered on the design center O2 and passes through the design junction point. Next, a pair of straight lines L2 are set that spread from the design center O2 to the left and right toward the design junction point at a predetermined angle α (for example, 15 degrees). In this embodiment, since the stator 2 is composed of six pieces 23a, the predetermined angle α is 15 degrees, but the predetermined angle α is set according to the number of pieces 23a that configure the stator 2. Then, a pair of perpendicular lines L3 are set to the pair of straight lines L2 that pass through an intersection O4 of the first virtual circle C1 and the pair of straight lines L2. A pair of second virtual circles C2 having a predetermined radius and with a center O5 on the pair of perpendicular lines L3 are set. Here, the predetermined radius of the second virtual circle C2 is set according to the radius of the stator 2. The predetermined radius of the second virtual circle C2 is preferably in the range of 30% to 100% of the radius of the stator 2, for example. The pair of opposing surfaces 23b-c are arranged on a tangent L4 that runs from the virtual point O3 to the pair of second virtual circles C2; in other words, the pair of opposing surfaces 23b-c are arranged on a tangent L4 that runs from the virtual point O3 to the pair of second virtual circles C2, with one end connected to the first recess 23b-a and the other end connected to the pair of second virtual circles C2, and the second virtual circle C2 forms a surface 23b-e that is closer to the inner periphery than the opposing portion 23b-d.

[0022] FIG. 7 is a plan view showing an example of a stator in which a plurality of segments are assembled, and FIG. 8 is a plan view showing an example of an engagement portion of the segments after bending. In FIG. 7, the stator 2 is configured by three segments 23 engaged in an arc shape in the circumferential direction. Since the segment 23 has two pieces 23a, the stator 2 is configured by six pieces 23a connected in an arc shape in the circumferential direction. The stator 2 configured by connecting six pieces 23a forms a hexagon (preferably a regular hexagon) P with vertices at the connection portion 23b of each piece 23a and the engagement portions 23c, 23d of each piece 23a constituting each segment 23. Specifically, the vertices of the connection portion 23b of each piece 23a are the opposing portions 23b-d.

[0023] In FIG. 8, when each segment 23 is bent inward at the connecting portion 23b, the pair of opposing surfaces 23b-c approach each other, and ideally, the pair of opposing portions 23b-d contact each other, but there are also cases where a gap is secured between them. At this time, the pair of opposing surfaces 23b-c gradually narrows in distance from the first recess 23b-a to the pair of opposing portions 23b-d. In other words, the pair of opposing surfaces 23b-c gradually narrows in distance from the first recess 23b-a to the pair of opposing portions 23b-d. That is, the gap between the pair of opposing surfaces 23b-c in the connecting portion 23b gradually narrows from the outer periphery side toward the inner periphery side. For example, the gap S1 on the outer periphery side between the pair of opposing surfaces 23b-c is 0.08 mm, and the gap S2 on the inner periphery side between the pair of opposing surfaces 23b-c is 0.02 mm. The size of the gaps S1 and S2 varies depending on tolerances and errors. The gaps S1 and S2 are smaller (approximately 1 / 10 to 1 / 5) than the radial gap between the stator 2 and rotor 3 in the assembled motor 1. That is, when each segment 23 is bent inward at the connecting portion 23b, ideally, the pair of opposing portions 23b-d come into line contact with each other, and therefore the gap between the pair of opposing surfaces 23b-c provided from the first recess 23b-a to the opposing portion 23b-d gradually narrows over the entire radial area.

[0024] Further, the shapes of the convex parts 23c-a, 23c-b and the concave parts 23c-c in the engagement part 23c, and the convex parts 23d-a, 23d-b and the concave parts 23d-c in the engagement part 23d will be described in detail. FIG. 9 is a plan view showing an example of the engagement part of the segments after assembly, and FIG. 10 is an explanatory diagram for setting the shape of the engagement part of the segments. In FIG. 9, one engagement part 23c is provided at an end of one piece 23a in the segment 23, and the other engagement part 23d is provided at an end of the other piece 23a in the segment 23. The engagement parts 23c and the engagement parts 23d of the two adjacent segments 23 come into contact with each other and engage with each other. The convex part 23c-a of one segment 23 engages with the concave part 23d-c of the other segment 23, and the concave part 23c-c of the one segment engages with the convex part 23d-b of the other segment.

[0025] In FIG. 10, an engagement line L11 is set along the radial direction through the center of the stator 2. Also, a tangent line L12 is set at the intersection of the engagement line L11 and a circumscribing circle (a circle passing through the design joint point) of the hexagon shown in FIG. 7 having its center at the center of the stator 2. Here, the position where the engagement line L11 and the tangent line L12 intersect perpendicularly is set as a virtual engagement point O11. A first inclined line L13 is set that passes through the virtual engagement point O11 and intersects with the tangent line L12 at a positive (counterclockwise) angle β. In this embodiment, the first inclined line L13 is set as a line running from the lower left side to the upper right side in FIG. 10 due to the shape of the engagement parts 23c and 23d described above, but if the shape of the engagement parts 23c and 23d is reversed, the first inclined line L13 is a line running from the lower right side to the upper left side.

[0026] The second inclined line L14 and the third inclined line L15 are set to intersect with the first inclined line L13 at acute angles θ1 and θ2. The second inclined line L14 intersects with the first inclined line L13 on one side in the length direction of the first inclined line L13, and the third inclined line L15 intersects with the first inclined line L13 on the other side in the length direction of the first inclined line L13. Here, since the second inclined line L14 and the third inclined line L15 are parallel, the acute angles θ1 and θ2 are the same angle. However, the acute angles θ1 and θ2 may be different angles, and the second inclined line L14 and the third inclined line L15 may not be parallel. In addition, it is preferable that the second inclined line L14 and the third inclined line L15 intersect with the engagement line L11 at the intermediate position between the engagement portion 23c and the engagement portion 23d.

[0027] In one of the engagement parts 23c, the protrusion 23c-a is composed of a first plane 23c-e along the second inclined line L14 and a third plane 23c-f along the first inclined line L13. The recess 23c-c is composed of a third plane 23c-g along the first inclined line L13 and a second plane 23c-h along the third inclined line L15. In the other of the engagement parts 23d, the recess 23d-c is composed of a first plane 23d-e along the second inclined line L14 and a third plane 23d-f along the first inclined line L13. The protrusion 23d-b is composed of a third plane 23d-g along the first inclined line L13 and a second plane 23d-h along the third inclined line L15.

[0028] The top 23c-d of the protrusion 23c-a in the engagement portion 23c protrudes in the circumferential direction of the stator 2 and toward the inner circumferential side. That is, the protrusion 23c-a and the recess 23c-c in the engagement portion 23c, and the protrusion 23d-b and the recess 23d-c in the engagement portion 23d are formed by a first inclined line L13, a second inclined line L14, and a third inclined line L15. The first inclined line L13, the second inclined line L14, and the third inclined line L15 are inclined in the same direction with respect to a tangent line L12 perpendicular to the engagement line L11.

[0029] The protrusion 23c-a engages with the recess 23d-c, and the protrusion 23d-b engages with the recess 23c-c. The engagement position between the protrusion 23c-a and the recess 23d-c and the engagement position between the protrusion 23d-b and the recess 23c-c are arranged side by side in the radial direction of the stator 2. That is, the first planes 23c-e, 23c-f, 23d-e, and 23d-f and the second planes 23c-g, 23c-h, 23d-g, and 23d-h are arranged side by side in the radial direction of the stator 2. The second planes 23c-g, 23c-h, 23d-g, and 23d-h are arranged on the inner circumferential side with respect to the first planes 23c-e, 23c-f, 23d-e, and 23d-f. The areas of the second planes 23c-h, 23d-h and the first planes 23c-e, 23d-e are larger than the areas of the first planes 23c-e, 23d-e, but this is not limited to the above, and the areas of the first planes 23c-e, 23d-e may be larger than the areas of the second planes 23c-h, 23d-h.

[0030] That is, the engagement portions 23c, 23d are provided with bulging portions 23g, 23h that protrude toward the inner circumferential side of the stator 2. The second planes 23c-h, 23d-h are disposed on the bulging portions 23g, 23h side. The contactable area between the second plane 23c-h of the recess 23c-c in the engagement portion 23c and the second plane 23d-h of the protrusion 23-b in the engagement portion 23d is larger than the contactable area between the first plane 23c-e of the protrusion 23c-a in the engagement portion 23c and the first plane 23d-e of the recess 23-c in the engagement portion 23d. Here, the engaging portion 23c and the engaging portion 23d are not necessarily in contact with the first plane 23c-e, 23c-f and the second plane 23c-g, 23c-h and the first plane 23d-e, 23d-f and the second plane 23d-g, 23d-h, but are in surface contact, line contact, or point contact state depending on the intersection and manufacturing error, and a gap is formed. The contactable area is the area when there is no design intersection or manufacturing error. In other words, it is the area of ​​the first plane 23c-e, 23d-e and the second plane 23c-h, 23d-h.

[0031] The size of the gap formed in the second plane 23c-h, 23d-h is smaller than the size of the gap formed in the first plane 23c-e, 23d-e. Specifically, the area of ​​the convex portion 23d-b and the concave portion 23c-c that can contact at the position of the third inclined line L15 is larger than the area of ​​the convex portion 23c-a and the concave portion 23d-c that can contact at the position of the second inclined line L14. The dimensional tolerance of the convex portion 23d-b and the concave portion 23c-c in the design at the position of the third inclined line L15 is smaller than the dimensional tolerance of the convex portion 23c-a and the concave portion 23d-c in the design at the position of the second inclined line L14. That is, in the adjacent segments 23, the positions of the convex portion 23c-b and the concave portion 23d-b that can contact the third inclined line L15 in the engagement portions 23c, 23d become the path (magnetic path) of the magnetic flux. However, the magnitude relationship between the first plane and the second plane may be reversed, and the first plane may be used as a path (magnetic path) for magnetic flux.

[0032] Fig. 11 is a plan view showing an example of a stator in which a plurality of segments are assembled. In Fig. 11, as described above, the stator 2 is configured by three segments 23 engaged in an arc shape in the circumferential direction. Since the segment 23 has two pieces 23a, the stator 2 is configured by six pieces 23a connected in an arc shape in the circumferential direction. The stator 2 configured by connecting six pieces 23a forms a hexagon P with vertices at the connecting portion 23b of each piece 23a and the engaging portions 23c, 23d of each piece 23a constituting each segment 23. Specifically, the vertices at the engaging portions 23c, 23d of each piece 23a are virtual engaging points O11.

[0033] Fig. 12 is a perspective view showing the multiple segments before assembly, and Fig. 13 is a perspective view showing the multiple segments after assembly. Note that this is a conceptual illustration of the formation of an annular core, and in reality, as described above, the upper insulator 24 and the lower insulator 25 are attached to each piece 23a of the segment 23, the coil is wound, and then bending is performed. In Fig. 12, the three segments 23 are each bent into an arc and then combined to form an annular core as shown in Fig. 13.

[0034] In a conventional stator in which a continuous strip-shaped core is bent into a ring shape, bending is performed in a single operation over a 360° range, which can cause excessive force to act on some connecting parts, deteriorating the circularity and causing vibration due to a radial excitation force corresponding to the number of magnetic poles of the magnet. In contrast, in this embodiment, multiple (e.g., three) segments 23 are each bent into an arc shape and then combined, improving the circularity. As a result, it is expected that vibration and noise due to a radial excitation force corresponding to the number of magnetic poles of the magnet will be reduced.

[0035] In addition, in a conventional stator in which a continuous band-shaped core is bent into a ring shape, the ends are connected at one point in one revolution, so the rigidity is low against the second and fourth circular vibration modes, which can also cause vibration and noise. In contrast, in this embodiment, the number of segments is an odd number, for example, three, so the connection parts of the segments do not face each other through the center of the circle, and the rigidity is high against the second and fourth circular vibration modes. As a result, a reduction in vibration and noise can be expected.

[0036] In the conventional stator, the segments are bent inward at the design position of the connecting portion to bring the pair of opposing surfaces into surface contact. In this case, if the bending start point of the segment is shifted from the design position, the pair of opposing surfaces will be in line contact, and a gap will be generated between the pair of opposing surfaces. Then, when a plurality of segments are combined in an annular shape, the roundness of the stator will decrease. In contrast, in the stator 2 of this embodiment, when the segments 23 are bent inward at the design position of the connecting portion 23b, a gap is intentionally generated between the pair of opposing surfaces 23b-c, and ideally, the pair of opposing portions 23b-d are in line contact with each other. Then, when the segments 23 are combined in an annular shape after being bent, a hexagon P having six vertices is formed. In this case, even if the bending start point of the segments 23 is shifted from the design position, the shape of the hexagon P is restricted and does not move significantly. Therefore, when a plurality of segments 23 are combined in an annular shape, the high roundness of the stator 2 is ensured. The six vertices of the hexagon P are the three opposing portions 23b-d and the three imaginary engagement points O11.

[0037] In addition, in a conventional stator, when a plurality of segments are combined into an annular shape, the engaging portions are engaged so as to simply come into contact with each other. In this case, although the segments are easily assembled, the engaging portions of the segments are not sufficiently engaged with each other, so that the segments move outward or inward around the engaging portions, causing deterioration of the roundness. In contrast, in the stator 2 of this embodiment, the convex portions 23c-a, 23d-b and the concave portions 23c-c, 23d-c of the engaging portions 23c, 23d are fitted to each other while forming acute angles. Therefore, the segments 23 are prevented from opening outward or inward at the engaging portions 23c, 23d, and deterioration of the roundness is suppressed.

[0038] That is, when combining three segments 23 in the stator 2, first, as shown in FIG. 12, the three segments 23 are arranged at intervals in the circumferential direction. Next, the three segments 23 are moved inward toward the center, and the engaging portions 23c, 23d are engaged with each other. Then, as shown in FIG. 13, the three segments 23 are combined in an annular shape to form the stator 2. In the stator 2 in which the three segments 23 are combined, one or two of the segments 23 are prevented from moving in the radial direction due to the shape of the engaging portions 23c, 23d. Therefore, the roundness is maintained and the stator 2 is easy to handle. However, when combining three segments 23, the three segments 23 may be moved in the axial direction to engage the engaging portions 23c, 23d to form the stator 2.

[0039] FIG. 14 is a perspective view showing a configuration example of a motor, and FIG. 15 is a divided perspective view showing a configuration example of the motor. In FIG. 14, the motor 1 includes a cylinder portion 11, lid portions 12 and 13, and a shaft 32. The cylinder portion 11 and the lid portions 12 and 13 form a housing. In FIG. 15, the stator 2 is inserted (press-fitted) into the cylindrical cylinder portion 11, the rotor 3 is disposed in the space inside the stator 2, and the shaft 32 of the rotor 3 is rotatably supported by the upper and lower lid portions 12 and 13 that hold bearings. In the longitudinal direction of the rotor 3, a surface 12a of the lid portion 12 facing the stator 2 is provided with a plurality of holes 12b, and an outer circumferential portion 12c of the lid portion 12 is provided with a plurality of holes 12d. Similarly, in the longitudinal direction of the rotor 3, a surface 13a of the lid portion 13 facing the stator 2 is provided with a plurality of holes 13b, and an outer circumferential portion 13c of the lid portion 13 is provided with a plurality of holes 13d. Fixation may be performed by inserting members such as screws into holes 12d, 13d provided in outer peripheries 12c, 13c of cover portions 12, 13 and holes 11a, 11b provided in the outer periphery of cylindrical portion 11. (In the illustrated example, rotor 3 has rotor yoke 3a as a magnetic body provided on shaft 32, and annular magnet 3b is provided on the outer periphery of rotor yoke 3a.

[0040] The rotor 3 may include a rotor yoke 3a formed in an annular shape by laminating electromagnetic steel sheets as magnetic members, and a shaft 32 may be provided in the center of the rotor yoke 3a, penetrating the rotor yoke 3a. For example, the rotor yoke 3a may be formed in an annular shape by bending four roughly sector-shaped pieces connected by connecting parts so as to sandwich the rod-shaped shaft 32, and the connecting parts at the ends of the segments are connected by laser welding or the like along the axial direction. The rotor yoke 3a may also be provided with holes that generate reluctance torque, and magnets may be disposed in the holes as necessary. The terminals 27 and the connecting plate 28 of the stator 2 are not shown in the figure.

[0041] Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the present invention.

[0042] As described above, the motor according to the present embodiment includes a stator, the stator includes a plurality of segments connected via an engagement portion, and the segments include a plurality of pieces connected via a connection portion. The pieces are arranged in an arc shape, and the segments are arranged in an annular shape. The engagement portion has two protruding portions protruding in the circumferential direction and a recessed portion provided between the two protruding portions. Of two adjacently arranged segments, the protruding portion of one segment engages with the recessed portion of the other segment, and the recessed portion of the one segment engages with the protruding portion of the other segment. The two protruding portions of the one and other segments have a top, and the protruding portion of the one segment and the recessed portion of the other segment have a first plane and a third plane that face each other. The first plane and the third plane extend in the radial and circumferential directions of the stator, and extend in directions that intersect each other toward the top. Therefore, by improving the roundness, it is possible to reduce vibration of the stator and improve productivity.

[0043] In addition, the tops of the protruding portions of the one and other segments protrude toward the inner circumference of the stator, so that the protruding portions and the recessed portions of the engaging portions engage properly, allowing for simple assembly and enabling the stator to be assembled properly with high circularity.

[0044] In addition, the recess of one segment and the protrusion of the other segment have second and third flat surfaces that face each other, and the second and third flat surfaces extend in the radial and circumferential directions of the stator and also extend in directions that intersect each other toward the apex, thereby further improving the roundness of the stator.

[0045] In addition, the first and second planes form acute angles with a line along the circumferential direction perpendicular to the center line along the radial direction of the stator, and the third plane forms a positive angle with a line along the circumferential direction perpendicular to the center line along the radial direction of the stator. Therefore, when adjacent segments are combined at the engagement portion, the segments can be prevented from opening outward and inward at the engagement portion.

[0046] In addition, the first and second planes are arranged side by side in the radial direction of the stator, the second plane is arranged on the inner circumferential side of the first plane, and the area of ​​the second plane is different from the area of ​​the first plane. Therefore, the position of the convex portion and the concave portion that engage with each other on the second plane becomes a magnetic path, and the cross-sectional area of ​​the flow path of the magnetic flux that interlinks with the stator winding is increased, and the magnetic resistance can be reduced, thereby suppressing the deterioration of motor performance.

[0047] In addition, the engaging portion has a bulge that protrudes toward the inner circumference, and the second plane is disposed on the bulge side. This makes it possible to ensure the cross-sectional area of ​​the flow path of the magnetic flux that interlinks with the stator winding without reducing the winding area in the inner circumference, and to suppress an increase in the outer diameter of the motor.

[0048] In addition, the gap formed in the larger of the first and second flat surfaces is smaller than the gap formed in the smaller of the first and second flat surfaces, so that the positions of the protruding and recessed portions that engage with each other on the first and second flat surfaces can be used as a magnetic path, thereby preventing an increase in the outer diameter of the motor.

[0049] In addition, the first plane on the outer periphery and the second plane on the inner periphery are arranged in parallel. Therefore, when adjacent segments are combined at the engagement parts, movement of the segments to the outer periphery and the inner periphery can be effectively suppressed. Furthermore, because a surface parallel to the center line of the teeth is formed at each engagement part of the segments before bending, the segments can be held in the winding machine with high precision using this surface, improving the space factor of the winding and reducing the time required to attach and detach the segments.

[0050] As described above, the motor according to this embodiment includes a stator, the stator includes a plurality of segments, and the segments include a plurality of pieces connected via a connecting portion. The pieces are arranged in an arc shape, and the segments are arranged in an annular shape. The connecting portion has a first recess, a pair of opposing surfaces whose one ends are continuous with both sides of the first recess, and a pair of opposing portions provided at the other ends of the pair of opposing surfaces. The distance between the pair of opposing surfaces decreases from the first recess to the pair of opposing portions. Therefore, by improving the roundness, it is possible to reduce vibration of the stator and improve productivity.

[0051] In addition, the pair of opposing surfaces are flat surfaces, so that a predetermined amount of gap can be secured between the pair of opposing surfaces.

[0052] The pair of opposing portions is a pair of opposing lines parallel to the direction of the rotation shaft of the motor, so that a predetermined amount of gap can be ensured between the pair of opposing surfaces, and the opposing lines can be in line contact with each other.

[0053] In addition, the pair of opposing portions are in contact with each other or face each other with a small gap therebetween, so that even if the bending positions of the segments are misaligned, deterioration in roundness can be suppressed.

[0054] In addition, a design center that is the center of bending rotation of the multiple pieces is set at the connecting portion, and a virtual point is set radially outward from the design center, and the pair of opposing surfaces are arranged on a pair of straight lines that connect the virtual point and the pair of opposing portions, so that a minute gap can be secured between the pair of opposing surfaces.

[0055] In addition, the design center and the imaginary point are located on a straight line that passes through the center of the motor and runs along the radial direction, so that even if the bending position of the segments is misaligned, deterioration of the circularity can be suppressed.

[0056] In addition, a first virtual circle is set that is centered on the design center and passes through the design joint point, a pair of second virtual circles having a predetermined radius and centered on a tangent to the first virtual circle are set, and the pair of opposing surfaces are disposed on the tangent that is tangent from the virtual point to the pair of second virtual circles, so that the pair of opposing surfaces can be set with high accuracy.

[0057] In addition, the area on the inner periphery side of the pair of opposing surfaces is positioned on a pair of second virtual circles. Therefore, the second virtual circles can be drawn with high accuracy, and the design accuracy of the pair of opposing surfaces can be improved. In this case, if the second virtual circles are positioned leaving a small gap in consideration of tolerances and errors, it becomes possible to perform correction processing for roundness in a later process, and the roundness can be further improved.

[0058] In addition, the connecting portion is provided with a first recess on the inner side in the radial direction of the motor, and a second recess on the outer side in the radial direction opposite to the first recess, so that the segments can be bent at predetermined positions.

[0059] In the above embodiment, the segment has two pieces, and the stator is formed by combining three segments, but the number of pieces in the segment and the number of segments to be combined are not limited to these. For example, the segment may have four pieces, and the stator may be formed by combining three segments.

[0060] Furthermore, the present invention is not limited to the above-mentioned embodiment. The present invention also includes a configuration in which the above-mentioned components are appropriately combined. Further effects and modifications can be easily derived by those skilled in the art. Therefore, the broader aspects of the present invention are not limited to the above-mentioned embodiment, and various modifications are possible. [Explanation of symbols]

[0061] 1 motor, 11 cylinder portion, 2, 21 stator, 23 segment, 23a piece, 23b connecting portion, 26 coil, 28 connection plate, 3 rotor, 32 shaft

Claims

1. A rotor and a stator are provided, The stator includes an odd number of segments connected via an engagement portion, The segment includes a plurality of pieces connected via connectors, The pieces are arranged in an arc shape, the odd number of segments are arranged in a ring, Each of the engagement portions of the odd number of segments has two protruding portions protruding in a circumferential direction and a recessed portion provided between the two protruding portions in a radial direction, Of the two adjacent segments, The protrusion of one segment engages with the recess of the other segment, The recess of the one segment engages with the protrusion of the other segment, The two protrusions of the one segment and the other segment each have an apex, the protruding portion of the one segment and the recessed portion of the other segment have a first plane and a third plane facing each other, The first plane and the third plane extend in a radial direction and a circumferential direction of the stator, and extend in directions intersecting each other toward the apex, a top portion of a protrusion of the one segment and the other segment protrudes toward an inner circumferential side of the stator, the recess of the one segment and the protrusion of the other segment have a second plane and a third plane facing each other, The second plane and the third plane extend in a radial direction and a circumferential direction of the stator, and extend in directions intersecting each other toward the apex, the first plane and the second plane form an acute angle with respect to a line along a circumferential direction perpendicular to a center line along a radial direction of the stator, and the third plane forms a positive angle with respect to a line along a circumferential direction perpendicular to the center line along the radial direction of the stator; The contactable area of ​​the second plane is larger than the contactable area of ​​the first plane. Motor.

2. 2. The motor according to claim 1, wherein the first plane and the second plane are arranged side by side in a radial direction of the stator, the second plane is arranged on an inner side of the first plane, and an area of ​​the second plane is different from an area of ​​the first plane.

3. The motor according to claim 2 , wherein the engaging portion has a bulging portion that protrudes to an inner peripheral side, and the second flat surface is disposed on a side of the bulging portion.

4. 4. The motor according to claim 2, wherein a gap formed in the plane having a larger area among the first plane and the second plane is smaller than a gap formed in the plane having a smaller area among the first plane and the second plane.

5. 5. The motor according to claim 1, wherein the first flat surface on the outer periphery side and the second flat surface on the inner periphery side are arranged in parallel.

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