Electric motor, core block and stator core

Abstract

The motor includes a stator core formed by connecting a plurality of core blocks in a circular ring shape, a first core block and a second core block which are connected together among the plurality of core blocks are respectively provided with a magnetic yoke part and a tooth part, the magnetic yoke part of the first core block is provided with a convex part, a first surface and a second surface, the magnetic yoke part of the second core block is provided with a concave part, a third surface and a fourth surface, the convex part is embedded in the concave part, and the third surface is embedded in the fourth surface. The first core block and the second core block are connected by surface contact between the first surface and the third surface, or by surface contact between the second surface and the fourth surface.

Description

Technical Field

[0001] The present disclosure relates to an electric motor, a core block for a stator core of the electric motor, and a stator core having the core block. Background Art

[0002] Electric motors are used in various electric devices such as household appliances and industrial appliances. As electric motors, there are known commutator motors using brushes and brushless motors not using brushes.

[0003] The brushless motor includes, for example, a rotor having a magnet and a stator having a stator core and a winding wound around the stator core. Conventionally, a technique of dividing a stator core into a plurality of core blocks (split cores) has been proposed (see, for example, Patent Document 1).

[0004] When the stator core is constituted by a plurality of core blocks, conventionally, the stator core is constituted by dividing the stator core by a number corresponding to the number of slots and combining the same number of core blocks as the number of divisions into a toroidal shape.

[0005] However, in this method, the shape of the core block is uniquely determined by the number of slots of the stator. In other words, the core block is a dedicated component corresponding to the number of slots of the stator. Therefore, if a stator core with a different number of slots is to be manufactured, a new core block has to be designed. In this case, a mold for manufacturing a new core block is required, or an insulator corresponding to the new core block is required, or a jig of a winding machine needs to be replaced in order to implement winding corresponding to the new core block. As a result, the cost will increase.

[0006] As described above, conventional core blocks have a problem in that they can only cope with stators having one type of slot number.

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Application Publication No. 2010-259174 Summary of the invention

[0010] The present disclosure is made to solve such a problem. An object of the present disclosure is to provide a motor, a core block, and a stator core that can handle stators having two different numbers of slots using one core block.

[0011] In order to achieve the above-mentioned object, in one embodiment of the electric motor disclosed in the present invention, the electric motor comprises: a stator having a stator core formed by connecting a plurality of core blocks in a circular ring shape; and a rotor having a rotating shaft, the rotor being arranged inside the stator, the plurality of core blocks having a first core block and a second core block connected together, the first core block and the second core block respectively having: a yoke portion extending in a circumferential direction centered on the axis of the rotating shaft; and a tooth portion extending from the yoke portion toward the rotating shaft, the yoke portion of the first core block and the tooth portion being connected to each other. The connecting portion connected to the yoke portion of the second core block is provided with a convex portion, a first surface located on the outer peripheral side of the convex portion, and a second surface located on the inner peripheral side of the convex portion. The connecting portion of the yoke portion of the second core block connected to the yoke portion of the first core block is provided with a concave portion, a third surface located on the outer peripheral side of the concave portion, and a fourth surface located on the inner peripheral side of the concave portion. The convex portion is embedded in the concave portion. The first core block and the second core block are connected by surface contact between the first surface and the third surface, or by surface contact between the second surface and the fourth surface.

[0012] Preferably, the first core blocks and the second core blocks are alternately connected throughout the entire circumference of the stator core, and the number of slots of the stator is different when the first surface is in contact with the third surface and when the second surface is in contact with the fourth surface.

[0013] The number of the grooves may be 9 when the first surface is in surface contact with the third surface, and the number of the grooves may be 6 when the second surface is in surface contact with the fourth surface.

[0014] The number of the grooves may be 12 when the first surface is in surface contact with the third surface, and the number of the grooves may be 9 when the second surface is in surface contact with the fourth surface.

[0015] In a plan view, the outer contour of the yoke portion of the first core block includes a first arc and a second arc having different radii of curvature. In a plan view, the outer contour of the yoke portion of the second core block includes a third arc and a fourth arc having different radii of curvature.

[0016] It may also be that, in the yoke portion of the first core block, the second arc is located at a position closer to the top end side of the yoke portion than the first arc, and in the yoke portion of the second core block, the fourth arc is located at a position closer to the top end side of the yoke portion than the third arc, and when the first surface is in surface contact with the third surface, the first arc and the third arc become arcs of the same circle.

[0017] It may also be that, in the yoke portion of the first core block, the second arc is located at a position closer to the top end side of the yoke portion than the first arc, and in the yoke portion of the second core block, the fourth arc is located at a position closer to the top end side of the yoke portion than the third arc, and when the second surface is in surface contact with the fourth surface, the second arc and the fourth arc become arcs of the same circle.

[0018] In the yoke portion of the first core block, the second arc is located closer to the top end of the yoke portion than the first arc, and in the yoke portion of the second core block, the fourth arc is located closer to the top end of the yoke portion than the third arc, and when the first surface is in surface contact with the third surface, the first arc and the third arc are arcs of the same circle. Alternatively, when the second surface is in surface contact with the fourth surface, the second arc and the fourth arc are arcs of the same circle.

[0019] Preferably, the diameter of the circle is 50 mm or less.

[0020] Preferably, in a plan view, an intersection point of a first straight line obtained by extending the first surface and a second straight line obtained by extending the second surface is located within the convex portion.

[0021] Alternatively, the electric motor may be a brushless motor.

[0022] In one embodiment of the core block disclosed herein, a stator core is formed by connecting a plurality of core blocks in a circular ring shape, wherein the core block comprises: a yoke portion extending along the circumferential direction of the stator core; and a tooth portion extending from the yoke portion toward the center portion of the stator core, wherein a convex portion, a first surface located on the outer circumferential side of the convex portion, and a second surface located on the inner circumferential side of the convex portion are provided at one circumferential end portion of the yoke portion, and a concave portion capable of being engaged with the convex portion, a third surface located on the outer circumferential side of the concave portion and capable of surface-to-surface contact with the first surface, and a fourth surface located on the inner circumferential side of the concave portion and capable of surface-to-surface contact with the second surface are provided at the other circumferential end portion of the yoke portion.

[0023] In one aspect of the stator core of the present disclosure, the stator core includes a plurality of the core blocks described above, and the plurality of core blocks are connected in a circular ring shape.

[0024] In one aspect of another electric motor of the present disclosure, the electric motor includes: a stator having the above-mentioned stator core and a winding wound around the stator core; and a rotor located at a position facing the stator.

[0025] According to the present disclosure, stators having two slot numbers can be realized by using one core block. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a cross-sectional view of the electric motor according to the embodiment cut along a plane passing through the rotation axis.

[0027] Figure 2 This is a cross-sectional view of the electric motor according to the embodiment when cut along a plane perpendicular to the rotation axis.

[0028] Figure 3 This is an exploded perspective view of the electric motor according to the embodiment as seen from obliquely above.

[0029] Figure 4 It is a plan view of the stator core according to the embodiment when a plurality of core blocks are connected by the first connection method.

[0030] Figure 5 It is a plan view of a core block constituting the stator core of the embodiment.

[0031] Figure 6 It is a plan view of the stator core according to the embodiment when a plurality of core blocks are connected by the second connection method. DETAILED DESCRIPTION

[0032] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. The embodiments described below all represent a specific example of the present disclosure. Therefore, the numerical values, constituent elements, configuration positions and connection forms of constituent elements, processes and the order of processes shown in the following embodiments are examples, and the main purpose is not to limit the present disclosure. Therefore, the constituent elements of the following embodiments that are not recorded in the independent claims representing the highest concept of the present disclosure are described as arbitrary constituent elements.

[0033] Each figure is a schematic diagram and is not necessarily a rigorous illustration. In each figure, the same reference numerals are used for structures that are substantially the same as those in other figures, and repeated descriptions are omitted or simplified. In this specification, the terms "upper" and "lower" do not necessarily refer to the upper direction (vertically above) and the lower direction (vertically below) in absolute spatial cognition.

[0034] (Implementation Method)

[0035] First, use Figure 1 to Figure 3 The structure of the electric motor 1 according to the embodiment will be described. Figure 1 It is a cross-sectional view of the motor 1 according to the embodiment when cut along a plane passing through the rotating shaft 31 . Figure 2 It is a cross-sectional view of the electric motor 1 according to the embodiment when cut along a plane perpendicular to the rotating shaft 31 . Figure 2 Indicates along Figure 1 The cross section of line II-II. Figure 3 This is an exploded perspective view of the electric motor 1 according to the embodiment as seen from obliquely above.

[0036] like Figure 1 to Figure 3 As shown, the motor 1 includes a stator 10, a circuit board 20, and a rotor 30 having a rotating shaft 31. The stator 10 and the circuit board 20 are combined into a stator assembly 2.

[0037] like Figure 1 As shown, the motor 1 further includes a first bearing 41 , a second bearing 42 , a first bracket 51 and a second bracket 52 .

[0038] The motor 1 is a brushless motor. The motor 1 can be used as a blower motor or a drive motor that is small and requires high output, for example. As an example, the size of the motor 1 is less than 50 mm in diameter. Specifically, the size of the motor 1 is, for example, 20 mm in diameter or 30 mm in diameter.

[0039] like Figure 1 and Figure 2 As shown, the electric motor 1 is an inner rotor type motor in which the rotor 30 is arranged inside the stator 10. That is, the stator 10 is arranged so as to surround the rotor 30. Therefore, the rotor 30 rotates inside the stator 10 with the axis C of the rotating shaft 31 as the rotation center.

[0040] A stator 10 is disposed opposite to the rotor 30 with a small air gap therebetween. Specifically, the stator 10 is disposed so as to surround a rotor core 32 of the rotor 30.

[0041] The stator 10 generates magnetic force acting on the rotor 30. Specifically, the stator 10 is configured such that a plurality of N poles and a plurality of S poles alternately and repeatedly exist in the air gap surface between the stator 10 and the rotor core 32 of the rotor 30 in the rotation direction to generate magnetic flux. The stator 10 and the rotor 30 together constitute a magnetic circuit.

[0042] The stator 10 constitutes an armature and includes a stator core 11 (stator iron core) and a winding 12 disposed on the stator core 11 . The winding 12 is a winding coil wound around the stator core 11 .

[0043] like Figure 2 As shown, the stator core 11 has a plurality of teeth 11a protruding toward the rotor 30. Specifically, the plurality of teeth 11a extend radially in a direction (radial direction) orthogonal to the axis C of the rotating shaft 31. The plurality of teeth 11a have slots 11b formed between two adjacent teeth 11a and are arranged at equal intervals in the circumferential direction. The stator core 11 has nine teeth 11a. That is, the number of slots in the stator 10 is nine.

[0044] The winding 12 is arranged in the slot 11b of the stator core 11. The winding 12 is a stator coil serving as an armature winding of the stator 10. As an example, the winding 12 is a concentrated winding coil wound around each tooth 11a.

[0045] The winding 12 is a three-phase winding so that the rotor 30 can be rotated as a three-phase synchronous motor. Specifically, the winding 12 is composed of unit coils of three phases, namely, the U phase, the V phase, and the W phase, which are 120 degrees different in electrical phase from each other. That is, the winding 12 wound on each tooth 11a is energized and driven by three-phase alternating current that is energized in phase units of the U phase, the V phase, and the W phase. As a result, the main magnetic flux of the stator 10 is generated in each tooth 11a. In other words, each tooth 11a is a magnetic pole tooth. Each tooth 11a is an electromagnet that generates magnetic force by the flow of current in the winding 12.

[0046] The stator core 11 is divided into a plurality of core blocks 110 (divided cores). In other words, the stator core 11 of the stator 10 is composed of a plurality of core blocks 110 .

[0047] The plurality of core blocks 110 are arranged in a circular ring shape as a whole. Specifically, the nine core blocks 110 are arranged in a circular ring shape. Two adjacent core blocks 110 are connected to each other. In other words, the stator core 11 is formed by connecting the plurality of core blocks in a circular ring shape. The windings 12 are respectively wound around the plurality of core blocks 110. Since the stator 10 has nine core blocks 110, nine windings 12 are used.

[0048] like Figure 2 As shown, the intermediate assembly 100 is composed of a core block 110 and a winding 12. The intermediate assembly 100 is an intermediate component used when manufacturing the stator assembly 2. The stator 10 is formed by combining a plurality of intermediate assemblies 100. Specifically, the stator 10 is formed by arranging a plurality of intermediate assemblies 100 in a cylindrical shape. The plurality of intermediate assemblies 100 are combined by connecting the core block 110 in a circular ring shape. The stator 10 is composed of 9 intermediate assemblies 100.

[0049] like Figure 2 and Figure 3 As shown, the core block 110 is provided for each intermediate assembly 100. The winding 12 of the stator 10 is also provided for each intermediate assembly 100. A connection terminal 120 and an insulator 130 are also provided for each intermediate assembly 100. Therefore, the plurality of intermediate assemblies 100 respectively include a core block 110, a winding 12, a connection terminal 120, and an insulator 130. The winding 12 is wound around the core block 110 via the insulator 130. The connection terminal 120 is fixed to the insulator 130. The detailed structure of the core block 110 will be described later.

[0050] like Figure 1 and Figure 3As shown, the circuit board 20 is, for example, a printed circuit board (PCB) in which wiring formed of a conductive material such as copper is formed in a predetermined pattern. As the base substrate of the circuit board 20, a resin substrate such as a glass epoxy substrate or a metal substrate such as an aluminum alloy substrate can be used. A plurality of electronic components (not shown) are mounted on the circuit board 20, and the plurality of electronic components are used to generate current supplied to the winding 12 of the stator 10. The plurality of electronic components constitute a circuit for generating three-phase alternating current of the U phase, the V phase, and the W phase.

[0051] The circuit board 20 is provided with a through hole 21. Figure 1 As shown, the connection terminal 120 of the intermediate assembly 100 corresponding to the core block 110 is connected to the through hole 21. The connection terminal 120 is a connection terminal connected to the winding 12 of the stator 10. The connection terminal 120 has a connection pin, and the connection pin of the connection terminal 120 connected to the winding 12 is inserted into the through hole 21. Thus, the connection terminal 120 and the circuit board 20 are connected. In this way, the circuit board 20 is a connection substrate connected to the winding 12 via the connection terminal 120. A plurality of through holes 21 are provided in the circuit board 20.

[0052] The connection pins of the connection terminals 120 are pressed into the through holes 21 of the circuit board 20. Thus, the connection terminals 120 can be fixed to the circuit board 20. The inner circumference of each through hole 21 is coated with a conductive film (for example, a copper plating layer), and the conductive film is electrically connected to the wiring formed on the main surface of the circuit board 20. Therefore, the connection pins of the connection terminals 120 are pressed into the through holes 21, so that the connection terminals 120 are mechanically connected to the circuit board 20. In addition, the connection terminals 120 are electrically connected to the wiring of the circuit board 20 via the conductive film coated on the inner circumference of the through holes 21.

[0053] The rotor 30 rotates under the action of the magnetic force generated by the stator 10. The rotor 30 is configured so that a plurality of N poles and a plurality of S poles alternately and repeatedly exist along the rotation direction. Thus, the rotor 30 generates a magnetic force acting on the stator 10. The direction of the magnetic flux generated by the rotor 30 is a direction orthogonal to the direction in which the axis C included in the rotating shaft 31 extends (axial direction). In other words, the direction of the magnetic flux generated by the rotor 30 is a radial direction (radial direction).

[0054] like Figure 1 and Figure 2 As shown, the rotor 30 includes a rotating shaft 31, a rotor core 32, and permanent magnets 33. The rotor 30 is an interior permanent magnet rotor (IPM (Interior Permanent Magnet) rotor) in which the permanent magnets 33 are embedded in the rotor core 32. Therefore, the motor 1 is an IPM motor.

[0055] The rotating shaft 31 is a longitudinally long shaft. The rotating shaft 31 is, for example, a metal rod. The rotating shaft 31 is fixed to the rotor core 32. Specifically, the rotating shaft 31 is inserted into a through hole provided in the center of the rotor core 32 so as to extend to both sides of the rotor core 32 in the direction in which the axis C extends, and is fixed to the rotor core 32.

[0056] The rotor core 32 is a laminated body formed by laminating a plurality of steel plates along the direction (axial direction) in which the axis C of the rotating shaft 31 extends. The plurality of steel plates are, for example, electromagnetic steel plates punched into a predetermined shape, and are fixed to each other by, for example, caulking.

[0057] The permanent magnet 33 is inserted into the magnet insertion hole 32a provided in the rotor core 32. Six magnet insertion holes 32a are provided in the rotor core 32 at equal intervals throughout the circumference. Therefore, the rotor 30 has six permanent magnets 33 arranged at equal intervals throughout the circumference. That is, the number of poles of the motor 1 is 6. The permanent magnet 33 is a sintered magnet. However, the permanent magnet 33 may also be a bonded magnet.

[0058] The first bearing 41 and the second bearing 42 for holding the rotating shaft 31 rotatably are provided on the rotating shaft 31 of the rotor 30. The first bearing 41 and the second bearing 42 are bearings for holding the rotating shaft 31 rotatably. The first bearing 41 supports the portion of the rotating shaft 31 protruding from one side of the rotor core 32. On the other hand, the second bearing 42 supports the portion of the rotating shaft 31 protruding from the other side of the rotor core 32. As an example, the first bearing 41 and the second bearing 42 are ball bearings. However, this is not limited thereto.

[0059] The first bracket 51 holds the first bearing 41. Specifically, the first bearing 41 is fixed to a recessed portion provided in the first bracket 51. The second bracket 52 holds the second bearing 42. Specifically, the second bearing 42 is fixed to a recessed portion provided in the second bracket 52. The first bracket 51 and the second bracket 52 are made of a metal material or a resin material.

[0060] The first bracket 51 and the second bracket 52 constitute the outer contour of the motor 1. Specifically, the first bracket 51 is a bottomed cylindrical frame (housing) having an opening. The second bracket 52 is a bottom plate that closes the opening of the first bracket 51. The first bracket 51 is a metal frame made of metal. The second bracket 52 is a resin plate made of resin.

[0061] The rotating shaft 31 of the rotor 30 passes through the first bracket 51. A portion of the rotating shaft 31 protrudes from the first bracket 51 to the outside. Although not shown, a load such as a rotary fan is mounted on the portion of the rotating shaft 31 protruding from the first bracket 51 to the outside. In other words, the portion of the rotating shaft 31 protruding from the first bracket 51 is the output shaft.

[0062] In the motor 1 thus constructed, when the winding 12 of the stator 10 is energized, a field current flows in the winding 12, thereby generating a magnetic flux in the stator 10 (stator core 11). As a result, a magnetic flux is generated from the stator 10 toward the rotor 30. Specifically, a magnetic flux is generated from the teeth 11a of the stator core 11 of the stator 10 toward the rotor core 32 of the rotor 30. On the other hand, in the rotor 30, a magnetic flux passing through the stator 10 is generated by the permanent magnets 33 embedded in the rotor core 32. The magnetic force generated by the interaction between the magnetic flux generated in the stator 10 and the magnetic flux generated from the permanent magnets 33 of the rotor 30 becomes a torque that rotates the rotor 30. As a result, the rotor 30 rotates.

[0063] Next, refer to Figure 1 to Figure 3 and use Figure 4 and Figure 5 The detailed shape of the core blocks 110 constituting the stator core 11 and the method of connecting the core blocks 110 will be described. Figure 4 It is a plan view of the stator core 11 according to the embodiment when a plurality of core blocks 110 are connected by the first connection method. Figure 5 It is a plan view of the core block 110 constituting the stator core 11 of the embodiment.

[0064] The core blocks 110 are each formed by stacking a plurality of steel plates. Specifically, each core block 110 is a stacked body formed by stacking a plurality of punched electromagnetic steel plates in a direction extending along the axis C of the rotating shaft 31. The electromagnetic steel plates constituting the core blocks 110 are of the same shape. The plurality of electromagnetic steel plates are fixed to each other by, for example, caulking.

[0065] like Figure 2 and Figure 4 As shown, each core block 110 has a tooth portion 111 and a yoke portion 112. The tooth portion 111 is Figure 2 The teeth 11 a of the stator core 11 are shown.

[0066] like Figure 4 As shown, the teeth 111 are formed inside the yoke 112. The teeth 111 extend from the yoke 112 toward the center of the stator core 11. Specifically, the teeth 111 extend from the yoke 112 toward the rotating shaft 31. That is, the teeth 111 extend in a manner protruding radially inward of the stator 10.

[0067] The tooth portion 111 has an extension portion 111a extending from the tip portion on the inner circumference side of the tooth portion 111 to both sides in the circumferential direction. The pair of extension portions 111a are formed so as to protrude from the tip portion on the inner circumference side of the tooth portion 111 in the circumferential direction. In two adjacent core blocks 110, a gap (notch) 111b exists between the extension portion 111a of the tooth portion 111 of one core block 110 and the extension portion 111a of the tooth portion 111 of the other core block 110.

[0068] A slot 11 b for arranging the winding 12 is formed between two adjacent teeth 111 . In other words, the slot 11 b is a space region on the side of the teeth 111 .

[0069] like Figure 2 As shown, the winding 12 is wound around the tooth portion 111. Specifically, the winding 12 is wound around the tooth portion 111 via an insulator 130.

[0070] like Figure 4 As shown, in the core block 110, the yoke portion 112 is a back yoke formed on the outside of the tooth portion 111. The yoke portion 112 extends along the circumferential direction of the stator core 11. The yoke portion 112 extends along the circumferential direction (the rotation direction of the rotating shaft 31) centered on the axis C of the rotating shaft 31. In two adjacent core blocks 110, the two adjacent yoke portions 112 are connected in a manner that the circumferential end surfaces abut against each other. Specifically, in Figure 4 In the embodiment, the nine yoke portions 112 are arranged along the circumferential direction of a circle centered on the axis C of the rotating shaft 31 , and are connected to form an annular shape as a whole.

[0071] like Figure 5 As shown, in each core block 110, a convex portion 113a and a first surface 114a and a second surface 115a located on both sides of the convex portion 113a are provided at a first end portion 112a which is one end portion in the circumferential direction of the yoke portion 112. The convex portion 113a, the first surface 114a, and the second surface 115a are formed on the end surface of the first end portion 112a facing the circumferential direction. When viewed from above, the convex portion 113a is sandwiched by the first surface 114a and the second surface 115a.

[0072] The convex portion 113a is formed to protrude from the first end portion 112a toward the circumferential direction of the stator core 11. The convex portion 113a is semicircular in plan view. Therefore, when the core block 110 is viewed in a three-dimensional manner, the convex portion 113a is semi-cylindrical in shape. The convex portion 113a is not limited to a semicircular in plan view.

[0073] The first surface 114a is located on the outer peripheral side of the convex portion 113a. Specifically, the first surface 114a is a plane parallel to a plane passing through the axis C of the rotating shaft 31. The first surface 114a extends from the root of the outer peripheral side of the convex portion 113a toward the outer peripheral side. The first surface 114a is a flat plane.

[0074] The second surface 115a is located on the inner circumference side of the convex portion 113a. Specifically, the second surface 115a is a plane parallel to a plane passing through the axis C of the rotating shaft 31. The second surface 115a extends from the root of the inner circumference side of the convex portion 113a toward the inner circumference side. The second surface 115a is a flat plane.

[0075] The first surface 114a and the second surface 115a are both surfaces facing the circumferential direction of the rotation axis 31. As for the first surface 114a and the second surface 115a, the inclination angle of the first surface 114a with respect to the radial direction of the rotation axis 31 and the inclination angle of the second surface 115a with respect to the radial direction of the rotation axis 31 are different. Figure 5 As shown, in a plan view of the core block 110 , the intersection of a first straight line L1 obtained by extending the first surface 114 a and a second straight line L2 obtained by extending the second surface 115 a is located within the convex portion 113 a .

[0076] On the other hand, the other end portion in the circumferential direction of the yoke portion 112, i.e., the second end portion 112b, is provided with a recessed portion 113b that can be fitted with the protruding portion 113a, and a third surface 114b and a fourth surface 115b located on both sides of the recessed portion 113b. The recessed portion 113b, the third surface 114b, and the fourth surface 115b are formed on the end surface of the second end portion 112b facing the circumferential direction. In a plan view, the recessed portion 113b is sandwiched by the third surface 114b and the fourth surface 115b.

[0077] The recess 113b is formed to be recessed from the second end 112b along the circumferential direction of the stator core 11. The shape of the recess 113b when viewed from above is semicircular. In other words, the surface of the recess 113b when viewed from above is an arc. Therefore, when the core block 110 is observed in three dimensions, the recess 113b is a shape in which the second end 112b is recessed in a semi-cylindrical shape. The shape of the recess 113b is not limited to this. The shape of the recess 113b may be any shape as long as it can be fitted with the protrusion 113a.

[0078] The third surface 114b is located on the outer peripheral side of the recess 113b. Specifically, the third surface 114b is a plane parallel to a plane passing through the axis C of the rotating shaft 31. The third surface 114b extends from the root of the outer peripheral side of the recess 113b toward the outer peripheral side. The third surface 114b is a flat plane.

[0079] The third surface 114b is a surface that can come into surface contact with the first surface 114a of the first end portion 112a of the yoke portion 112. Therefore, the first surface 114a of the first end portion 112a of the yoke portion 112 is a surface that can come into surface contact with the third surface 114b.

[0080] The fourth surface 115b is located on the inner peripheral side of the recess 113b. Specifically, the fourth surface 115b is a plane parallel to a plane passing through the axis C of the rotating shaft 31. The fourth surface 115b extends from the root of the inner peripheral side of the recess 113b toward the inner peripheral side. The fourth surface 115b is a flat plane.

[0081] The fourth surface 115b is a surface that can come into surface contact with the second surface 115a of the first end portion 112a of the yoke portion 112. Therefore, the second surface 115a of the first end portion 112a of the yoke portion 112 is a surface that can come into surface contact with the fourth surface 115b.

[0082] The third surface 114b and the fourth surface 115b are both surfaces facing the circumferential direction of the rotation axis 31. As for the third surface 114b and the fourth surface 115b, the inclination angle of the third surface 114b with respect to the radial direction of the rotation axis 31 and the inclination angle of the fourth surface 115b with respect to the radial direction of the rotation axis 31 are different. Figure 5 As shown, when the core block 110 is viewed from above, the intersection of the third straight line L3 obtained by extending the third surface 114b and the fourth straight line L4 obtained by extending the fourth surface 115b is located in the recessed portion 113b.

[0083] The outer section of the yoke portion 112 includes two curved surfaces (R surfaces) having different curvature radii. Figure 5 As shown, in a plan view, the outer contour of the yoke portion 112 of the core block 110 includes a plurality of arcs having different curvature radii.

[0084] The outer contour of one side of the yoke portion 112 in the circumferential direction with respect to the tooth portion 111 as a reference includes a first arc 116a and a second arc 117a having different curvature radii. The curvature radius R2 of the second arc 117a is larger than the curvature radius R1 of the first arc 116a (R2>R1). In this case, the second arc 117a is located closer to the top end side of the yoke portion 112 than the first arc 116a. The length of the arc of the second arc 117a is shorter than the length of the arc of the first arc 116a. The first arc 116a and the second arc 117a are continuous.

[0085] On the other hand, the outer contour of the other side of the yoke portion 112 in the circumferential direction based on the tooth portion 111 includes a third arc 116b and a fourth arc 117b having different radii of curvature. The curvature radius R4 of the fourth arc 117b is larger than the curvature radius R3 of the third arc 116b (R4>R3). In this case, the fourth arc 117b is located closer to the top end side of the yoke portion 112 than the third arc 116b. The length of the fourth arc 117b is shorter than the length of the third arc 116b. The third arc 116b and the fourth arc 117b are continuous.

[0086] The curvature radius R3 of the third circular arc 116b is the same as the curvature radius R1 of the first circular arc 116a (R1=R3). The curvature radius R4 of the fourth circular arc 117b is the same as the curvature radius R2 of the second circular arc 117a (R2=R4).

[0087] like Figure 4As shown in FIG. 1 , a plurality of core blocks 110 thus constructed are arranged in a circular ring and connected. The plurality of core blocks 110 arranged in a circular ring are connected to each other by connecting the yoke portions 112 of two adjacent core blocks 110. The plurality of core blocks 110 are all of the same shape. That is, the stator core 11 is composed only of Figure 5 The core block 110 of the shape shown is constructed.

[0088] At this time, if Figure 4 As shown in the enlarged view of FIG. 1 , focusing on two core blocks 110, namely, the first core block 110a and the second core block 110b, which are connected together among the plurality of core blocks 110, a convex portion 113a, a first surface 114a located on the outer peripheral side of the convex portion 113a, and a second surface 115a located on the inner peripheral side of the convex portion 113a are provided at the connection portion of the yoke portion 112 of the first core block 110a connected to the yoke portion 112 of the second core block 110b. In other words, the convex portion 113a, the first surface 114a, and the second surface 115a are provided at the first end portion 112a of the yoke portion 112 of the first core block 110a on the side close to the second core block 110b.

[0089] The yoke part 112 of the second core block 110b is provided with a recessed part 113b, a third surface 114b located on the outer peripheral side of the recessed part 113b, and a fourth surface 115b located on the inner peripheral side of the recessed part 113b at the connection part connected to the yoke part 112 of the first core block 110a. In other words, the recessed part 113b, the third surface 114b, and the fourth surface 115b are provided at the second end 112b of the yoke part 112 of the second core block 110b on the side close to the first core block 110a.

[0090] At the connection portion between the first core block 110a and the second core block 110b, the convex portion 113a of the yoke portion 112 of the first core block 110a and the concave portion 113b of the yoke portion 112 of the second core block 110b are fitted.

[0091] The first core blocks 110a and the second core blocks 110b are alternately connected throughout the entire circumference of the stator core 11. That is, the stator core 11 is composed of a plurality of core blocks 110 including the first core blocks 110a and the second core blocks 110b.

[0092] exist Figure 4 In the stator core 11 shown, nine core blocks 110 are connected together. Figure 4 The number of slots of the stator 10 of the stator core 11 shown is 9. In this case, Figure 4 As shown, in the first core block 110a and the second core block 110b connected to each other, the first surface 114a of the yoke portion 112 of the first core block 110a is in surface contact with the third surface 114b of the yoke portion 112 of the second core block 110b. Figure 4In the image, the first surface 114a becomes the contact surface with the third surface 114b. The third surface 114b becomes the contact surface with the first surface 114a. Figure 4 When the core blocks 110 are connected in this manner, the first surface 114 a and the third surface 114 b serve as mating surfaces of the core blocks 110 .

[0093] On the other hand, Figure 4 In the embodiment, the second surface 115a of the yoke portion 112 of the first core block 110a and the fourth surface 115b of the yoke portion 112 of the second core block 110b are not in contact. In other words, there is a gap between the second surface 115a and the fourth surface 115b. The second surface 115a and the fourth surface 115b are separated. Therefore, in the image Figure 4 When the core blocks 110 are connected in this manner, the second surface 115 a and the fourth surface 115 b are non-contact surfaces.

[0094] When the first surface 114 a of the first core block 110 a and the third surface 114 b of the second core block 110 b are in surface contact with each other as described above, the number of slots of the stator 10 including the stator core 11 becomes nine.

[0095] like Figure 4 As shown, when the first surface 114a of the first core block 110a and the third surface 114b of the second core block 110b are in surface contact, the first arc 116a in the outer contour of the yoke portion 112 of the first core block 110a and the third arc 116b in the outer contour of the yoke portion 112 of the second core block 110b become arcs of the same circle. In this case, the diameter of the circle including the first arc 116a and the third arc 116b is less than 50 mm.

[0096] like Figure 4 As shown, when the first surface 114a of the first core block 110a and the third surface 114b of the second core block 110b are in surface contact (that is, in the case of the first connection method), the first surface 114a and the third surface 114b that form the contact surface are consistent with the radial direction of the rotating shaft 31 when viewed from above.

[0097] In this way, in two adjacent core blocks 110, the convex portion 113a of the first core block 110a and the concave portion 113b of the second core block 110b are fitted together and the first surface 114a of the first core block 110a and the third surface 114b of the second core block 110b are in surface contact, thereby connecting nine core blocks 110. In other words, by connecting nine core blocks 110 to manufacture the stator core 11, a stator 10 having nine slots can be obtained.

[0098] Figure 6 FIG. 1 is a top view of a stator core 11 of the embodiment when a plurality of core blocks 110 are connected by the second connection method. Figure 6As shown, by fitting the convex portion 113a of the first core block 110a with the concave portion 113b of the second core block 110b and making the second surface 115a of the first core block 110a and the fourth surface 115b of the second core block 110b in surface contact, six core blocks 110 can be connected. That is, by connecting six core blocks 110 to produce the stator core 11, a stator 10 having six slots can be obtained.

[0099] like Figure 6 As shown, when the plurality of core blocks 110 are connected by the second connection method, in the two adjacent core blocks 110, the second surface 115a of the first core block 110a and the fourth surface 115b of the second core block 110b become contact surfaces. Figure 6 In the image, the second surface 115a becomes the contact surface with the fourth surface 115b. The fourth surface 115b becomes the contact surface with the second surface 115a. Figure 6 When the core blocks 110 are connected in this manner, the second surface 115 a and the fourth surface 115 b serve as mating surfaces of the core blocks 110 .

[0100] exist Figure 6 In the case of the second connection mode shown in FIG. 1 , the first surface 114a of the yoke portion 112 of the first core block 110a and the third surface 114b of the yoke portion 112 of the second core block 110b are not in contact. In other words, there is a gap between the first surface 114a and the third surface 114b. The first surface 114a and the third surface 114b are separated. In other words, Figure 6 In the embodiment, the first surface 114a and the third surface 114b are non-contact surfaces.

[0101] like Figure 6 As shown, when the second surface 115a of the first core block 110a and the fourth surface 115b of the second core block 110b are in surface contact, the second arc 117a in the outer contour of the yoke portion 112 of the first core block 110a and the fourth arc 117b in the outer contour of the yoke portion 112 of the second core block 110b become arcs of the same circle. In this case, the diameter of the circle including the second arc 117a and the fourth arc 117b is less than 50 mm. Figure 6 The diameter ratio of the stator core 11 in the case of the second connection method shown is Figure 4 In the case of the first connection form shown, the diameter of the stator core 11 is small.

[0102] like Figure 6 As shown, when the second surface 115a of the first core block 110a and the fourth surface 115b of the second core block 110b are in surface contact (that is, in the case of the second connection method), the second surface 115a and the fourth surface 115b forming the contact surface are consistent with the radial direction of the rotating shaft 31 when viewed from above.

[0103] As described above, the core block 110 of the present embodiment includes the tooth portion 111 and the yoke portion 112. The convex portion 113a, the first surface 114a located on the outer peripheral side of the convex portion 113a, and the second surface 115a located on the inner peripheral side of the convex portion 113a are provided at the first end portion 112a in the circumferential direction of the yoke portion 112. The concave portion 113b that can be fitted with the convex portion 113a, the third surface 114b located on the outer peripheral side of the concave portion 113b, and the fourth surface 115b located on the inner peripheral side of the concave portion 113b are provided at the second end portion 112b in the circumferential direction of the yoke portion 112.

[0104] When the stator core 11 is manufactured by connecting a plurality of core blocks 110 of such a shape, two adjacent core blocks 110 of the plurality of core blocks 110, namely, a first core block 110a and a second core block 110b, are connected as shown in FIG. Figure 4 As shown, the first surface 114a and the third surface 114b are connected by surface contact, or as shown Figure 6 As shown in FIG. 1 , the second surface 115a and the fourth surface 115b are connected by surface contact. Figure 4 As shown in FIG. 1 , a plurality of core blocks 110 are connected by a first connection method in which the first surface 114a and the third surface 114b are in surface contact with each other, or as shown in FIG. Figure 6 As shown, the plurality of core blocks 110 are connected by the second connection method in which the second surface 115a and the fourth surface 115b are in surface contact with each other.

[0105] Thus, in the case where the first surface 114a and the third surface 114b are in surface contact and in the case where the second surface 115a and the fourth surface 115b are in surface contact, the stator 10 having different numbers of slots can be realized. Figure 4 As shown in FIG. 1 , the number of grooves when the first surface 114a and the third surface 114b are in surface contact is 9. Figure 6 As shown in FIG. 1 , the number of grooves when the second surface 115a and the fourth surface 115b are in contact with each other is 6. That is, by selecting the number of grooves in accordance with the required number of grooves, Figure 4 The first connection method shown and Figure 6 The core blocks 110 are connected in the second connection mode shown, and two numbers of grooves can be realized.

[0106] By using the core block 110 in this way, the stator 10 having two different slot numbers can be realized by using one core block 110. In other words, one core block 110 can be used in two ways.

[0107] In the two adjacent core blocks 110, namely, the first core block 110a and the second core block 110b, the outer contour of the yoke portion 112 of the first core block 110a includes a first arc 116a and a second arc 117a having different radii of curvature. The outer contour of the yoke portion 112 of the second core block 110b includes a third arc 116b and a fourth arc 117b having different radii of curvature.

[0108] This can prevent the first surface 114a from contacting the third surface 114b. Figure 4 In the case of the first connection method (the case of the first connection method), the connection portion between the first core block 110a and the second core block 110b and the second surface 115a and the fourth surface 115b are in surface contact ( Figure 6 In the case of the second connection method (the case of the second connection method), any one of the connection parts between the first core block 110a and the second core block 110b has an edge.

[0109] For example, assuming that the outer contour of the yoke portion 112 of the core block 110 is composed of only one arc, Figure 6 When the first core block 110a and the second core block 110b are connected in a manner such that the second surface 115a on the inner circumference side and the fourth surface 115b are in surface contact, the connection portion between the first core block 110a and the second core block 110b is angular, and a corner portion is formed on the outer surface of the stator core 11. In this case, Figure 2 As shown, the outer surface of the stator core 11 abuts against the inner surface of the first bracket 51 (frame). Therefore, if a corner is formed on the outer surface of the stator core 11, the corner will point-contact with the inner surface of the first bracket 51. As a result, stress from the first bracket 51 is applied to the stator core 11. As a result, there is a possibility that the stator core 11 is damaged, or the stator core 11 is misaligned and the desired magnetic flux cannot be generated.

[0110] In contrast, by including arcs with different curvature radii in the outer contour of the yoke portion 112 of the core block 110 as in the present embodiment, it is possible to prevent the connection portion between the first core block 110a and the second core block 110b from having an angular shape as described above. Specifically, it is possible to prevent Figure 6 When the first core block 110a and the second core block 110b are connected so that the second surface 115a and the fourth surface 115b on the inner circumference side are in surface contact, the connection portion between the first core block 110a and the second core block 110b is angular.

[0111] As described above, the motor 1 of the present embodiment includes: a stator 10 having a stator core 11 formed by connecting a plurality of core blocks 110 in an annular shape; and a rotor 30 having a rotating shaft 31, and the rotor 30 is arranged inside the stator 10. The plurality of core blocks 110 include a first core block 110a and a second core block 110b connected together. The first core block 110a and the second core block 110b each include a yoke portion 112 extending in a circumferential direction centered on the axis of the rotating shaft 31 and a tooth portion 111 extending from the yoke portion 112 toward the rotating shaft 31. The yoke portion 112 of the first core block 110a is provided at a connection portion connected to the yoke portion 112 of the second core block 110b, a convex portion 113a, a first surface 114a located on the outer peripheral side of the convex portion 113a, and a second surface 115a located on the inner peripheral side of the convex portion 113a. The yoke part 112 of the second core block 110b is connected to the yoke part 112 of the first core block 110a, and is provided with a recessed part 113b, a third surface 114b located on the outer peripheral side of the recessed part 113b, and a fourth surface 115b located on the inner peripheral side of the recessed part 113b, and the protrusion 113a is embedded in the recessed part 113b. The first core block 110a and the second core block 110b are connected by the first surface 114a and the third surface 114b being in surface contact, or by the second surface 115a and the fourth surface 115b being in surface contact.

[0112] Thus, stators having two different numbers of slots can be realized using one core block.

[0113] The core block 110 of the present embodiment is formed by connecting a plurality of core blocks 110 in an annular shape to form a stator core 11, wherein the core block 110 has a yoke portion 112 extending along the circumferential direction of the stator core 11 and a tooth portion 111 extending from the yoke portion 112 toward the center of the stator core 11. A convex portion 113a, a first surface 114a located on the outer circumferential side of the convex portion 113a, and a second surface 115a located on the inner circumferential side of the convex portion 113a are provided at one end portion in the circumferential direction of the yoke portion 112. A concave portion 113b that can be fitted with the convex portion 113a, a third surface 114b located on the outer circumferential side of the concave portion 113b and capable of surface contact with the first surface 114a, and a fourth surface 115b located on the inner circumferential side of the concave portion 113b and capable of surface contact with the second surface 115a are provided at the other end portion in the circumferential direction of the yoke portion 112.

[0114] The electric motor 1 of the present embodiment includes a stator 10 including a stator core 11 and a winding wound around the stator core 11 , and a rotor 30 located at a position facing the stator 10 .

[0115] (Variation Example)

[0116] As mentioned above, although this disclosure was described based on embodiment, this disclosure is not limited to the said embodiment.

[0117] For example, in the above embodiment, the core block 110 is shaped such that the number of grooves when the first surface 114a and the third surface 114b are in surface contact is 9, and the number of grooves when the second surface 115a and the fourth surface 115b are in surface contact is 6. However, the present invention is not limited thereto. Specifically, the core block 110 may be shaped such that the number of grooves when the first surface 114a and the third surface 114b are in surface contact is 12, and the number of grooves when the second surface 115a and the fourth surface 115b are in surface contact is 9.

[0118] In the above embodiment, the rotor 30 is an IPM rotor. However, the present invention is not limited thereto. For example, the rotor 30 may be a surface magnet rotor (SPM (Surface Permanent Magnetic) rotor) in which a plurality of permanent magnets are provided on the outer surface of the rotor core.

[0119] In the above embodiment, the rotor 30 is a laminated body formed by laminating a plurality of steel plates. However, the present invention is not limited thereto. For example, the rotor 30 may be formed of a block material.

[0120] In addition, various modifications that can be conceived by those skilled in the art to the above-mentioned embodiments or arbitrarily combining the components and functions of the above-mentioned embodiments within the scope not departing from the gist of the present disclosure are also included in the present disclosure.

[0121] Industrial Applicability

[0122] The technology disclosed herein can be widely used in electric motors, electric equipment including electric motors, and the like.

[0123] Description of Reference Numerals

[0124] 1. Motor; 2. Stator assembly; 10. Stator; 11. Stator core; 11a. Teeth; 11b. Slots; 12. Winding; 20. Circuit board; 21. Through hole; 30. Rotor; 31. Rotating shaft; 32. Rotor core; 32a. Magnet insertion hole; 33. Permanent magnet; 41. First bearing; 42. Second bearing; 51. First bracket; 52. Second bracket; 100. Intermediate assembly; 110. Core block; 110a. First core block; 110b. Second core block ; 111, tooth portion; 111a, extension portion; 111b, gap (slot); 112, yoke portion; 112a, first end portion; 112b, second end portion; 113a, convex portion; 113b, concave portion; 114a, first surface; 115a, second surface; 114b, third surface; 115b, fourth surface; 116a, first arc; 117a, second arc; 116b, third arc; 117b, fourth arc; 120, connecting terminal; 130, insulator.

Claims

1. An electric motor, wherein: The motor includes: A stator having a stator core formed by connecting a plurality of core blocks in a circular ring shape; and a rotor having a rotating shaft, the rotor being arranged inside the stator, The plurality of core blocks include a first core block and a second core block connected together, The first core block and the second core block each have: a yoke portion extending in a circumferential direction centered on the axis of the rotating shaft; and a tooth portion extending from the yoke portion toward the rotating shaft, A connecting portion of the yoke portion of the first core block connected to the yoke portion of the second core block is provided with a convex portion, a first surface located on the outer peripheral side of the convex portion, and a second surface located on the inner peripheral side of the convex portion. A connecting portion of the yoke portion of the second core block connected to the yoke portion of the first core block is provided with a recessed portion, a third surface located on the outer peripheral side of the recessed portion, and a fourth surface located on the inner peripheral side of the recessed portion, and the convex portion is embedded in the recessed portion. The first core block and the second core block are connected by the first surface and the third surface being in surface contact, or are connected by the second surface and the fourth surface being in surface contact.

2. The electric motor according to claim 1, wherein: The first core blocks and the second core blocks are connected alternately over the entire circumference of the stator core. The number of slots of the stator is different between the case where the first surface is in contact with the third surface and the case where the second surface is in contact with the fourth surface.

3. The electric motor according to claim 2, wherein: The number of grooves when the first surface and the third surface are in surface contact is 9, The number of grooves when the second surface is in surface contact with the fourth surface is 6.

4. The electric motor according to claim 2, wherein: When the first surface and the third surface are in surface contact, the number of grooves is 12. The number of grooves when the second surface is in surface contact with the fourth surface is nine.

5. The electric motor according to any one of claims 1 to 4, wherein: In a plan view, the outer contour of the yoke portion of the first core block includes a first arc and a second arc having different curvature radii. In a plan view, the outer contour of the yoke portion of the second core block includes a third arc and a fourth arc having different curvature radii.

6. The electric motor according to claim 5, wherein: In the yoke portion of the first core block, the second arc is located closer to the front end side of the yoke portion than the first arc. In the yoke portion of the second core block, the fourth arc is located closer to the front end side of the yoke portion than the third arc. When the first surface and the third surface are in surface contact, the first arc and the third arc become arcs of the same circle.

7. The electric motor according to claim 5, wherein: In the yoke portion of the first core block, the second arc is located closer to the front end side of the yoke portion than the first arc. In the yoke portion of the second core block, the fourth arc is located closer to the front end side of the yoke portion than the third arc. When the second surface is in surface contact with the fourth surface, the second arc and the fourth arc become arcs of the same circle.

8. The electric motor according to claim 5, wherein: In the yoke portion of the first core block, the second arc is located closer to the front end side of the yoke portion than the first arc. In the yoke portion of the second core block, the fourth arc is located closer to the front end side of the yoke portion than the third arc. When the first surface and the third surface are in surface contact, the first arc and the third arc become arcs of the same circle, or When the second surface is in surface contact with the fourth surface, the second arc and the fourth arc become arcs of the same circle.

9. The electric motor according to any one of claims 6 to 8, wherein: The diameter of the circle is 50 mm or less.

10. The electric motor according to any one of claims 1 to 4, wherein: In a plan view, an intersection point of a first straight line obtained by extending the first surface and a second straight line obtained by extending the second surface is located within the convex portion.

11. The electric motor according to any one of claims 1 to 4, wherein: The electric motor is a brushless motor.

12. A core block, wherein a plurality of the core blocks are connected in a circular ring shape to form a stator core, wherein: The core block has: a yoke portion extending along the circumferential direction of the stator core; as well as a tooth portion extending from the yoke portion toward a center portion of the stator core, A convex portion, a first surface located on the outer circumference side of the convex portion, and a second surface located on the inner circumference side of the convex portion are provided at one end portion of the yoke portion in the circumferential direction. A recessed portion engageable with the convex portion, a third surface located on the outer circumferential side of the recessed portion and capable of surface contact with the first surface, and a fourth surface located on the inner circumferential side of the recessed portion and capable of surface contact with the second surface are provided at the other circumferential end of the yoke portion.

13. A stator core, wherein: The stator core comprises a plurality of core blocks according to claim 12, The plurality of core blocks are connected in a circular ring shape.

14. An electric motor, wherein: The motor includes: A stator comprising the stator core according to claim 13 and a winding wound around the stator core; and The rotor is located facing the stator.

Images