Stator and motor provided with same

Abstract

This stator comprises a stator core and coils. The stator core has: an annular core back surrounding the central axis; and teeth. A plurality of teeth extend radially inward from the core back and are circumferentially arranged. The coils are each composed of a conductor wound around the teeth. The core back has a plurality of through-holes penetrating in the radial direction and disposed in the circumferential direction. Each tooth has a projection that protrudes radially outward from a radially outer end and is disposed inside a through-hole.

Description

Stator and motor having the same

[0001] The present invention relates to a stator and a motor including the same.

[0002] A conventional stator includes, for example, a stator core and a coil. The stator core has an annular core back surrounding a central axis and teeth. The teeth extend radially inward from the core back and are arranged in a circumferential direction. The coil is formed by a conducting wire wound around the teeth (see, for example, Patent Document 1).

[0003] Chinese Patent Application Publication No. 106532992

[0004] However, in conventional stators, the workability of assembling the stator core and the teeth is low, and the adhesive strength between the stator core and the teeth is low, which can result in a decrease in strength.

[0005] An object of the present invention is to provide a stator that can improve assembly workability and strength.

[0006] An exemplary stator of the present invention includes a stator core and coils. The stator core has an annular core back surrounding a central axis and teeth. The teeth extend radially inward from the core back and are arranged in a circumferential direction. The coils are formed by conductive wires wound around the teeth. The core back has a plurality of through holes that penetrate radially and are arranged in the circumferential direction. Each tooth has a protrusion that protrudes radially outward from its radial outer end and is arranged inside the through hole.

[0007] According to an exemplary embodiment of the present invention, a stator can be provided that can improve assembly workability and strength.

[0008] FIG. 1 is a longitudinal sectional view schematically showing a motor according to a first exemplary embodiment of the present invention. FIG. 2 is a top view of a stator according to the first exemplary embodiment of the present invention. FIG. 3 is a perspective view showing an enlarged portion of the stator according to the first exemplary embodiment of the present invention. FIG. 4 is a perspective view of teeth of the stator according to the first exemplary embodiment of the present invention. FIG. 5 is a sectional view showing an enlarged portion of the stator according to the first exemplary embodiment of the present invention. FIG. 6 is a flowchart showing a manufacturing process of the stator according to the first exemplary embodiment of the present invention. FIG. 7 is a perspective view showing an enlarged portion of a stator according to a second exemplary embodiment of the present invention. FIG. 8 is a longitudinal sectional view schematically showing a motor according to a third exemplary embodiment of the present invention. FIG. 9 is a perspective view schematically showing a mounting member of the motor according to the third exemplary embodiment of the present invention. FIG. 10 is a perspective view showing an enlarged portion of a coil of a motor according to the first exemplary embodiment of the present invention.

[0009] An exemplary embodiment of the present invention will be described in detail below with reference to the drawings. In this specification, the direction parallel to the central axis J of the motor 1 is referred to as the "axial direction," the direction perpendicular to the central axis J of the motor 1 is referred to as the "radial direction," and the direction along the arc centered on the central axis J of the motor 1 is referred to as the "circumferential direction." In this application, the shape and positional relationship of each part will be described with the axial direction defined as the up-down direction and the bearing 81 positioned below the bearing 82. Note that the up-down direction is a term used merely for the purpose of explanation and does not limit the actual positional relationship or direction.

[0010] In the present application, the term "parallel direction" includes a direction that is substantially parallel to the other, and the term "perpendicular direction" includes a direction that is substantially perpendicular to the other.

[0011] First Embodiment (1. Motor Configuration) A stator according to an exemplary embodiment of the present invention will be described. Fig. 1 is a vertical cross-sectional view schematically showing a motor 1 according to a first embodiment of the present invention. The motor 1 includes a rotor 10, a stator 20, and a housing 100.

[0012] The rotor 10 includes a columnar shaft 11 that forms a rotation axis extending along a central axis J, a magnet holder 12, and a plurality of magnets 13. The magnet holder 12 is formed in a disk shape and has an insertion hole 12a that extends in the axial direction. The shaft 11 is inserted into the insertion hole 12a and fixed to the magnet holder 12.

[0013] The magnets 13 are fixed to the radially outer end of the magnet holder 12 by, for example, an adhesive (not shown). The magnets 13 are arranged in the circumferential direction, for example, so that the north poles and south poles are arranged alternately.

[0014] The housing 100 is formed in a cylindrical shape and accommodates the stator 20. The housing 100 has a bottom plate portion 101, a top plate portion 102, and a side plate portion 103. The side plate portion 103 is formed in a cylindrical shape and covers the stator 20 from the radial outside. The bottom plate portion 101 is disposed axially below the stator 20 and covers the open lower end of the side plate portion 103. The bottom plate portion 101 holds the bearing 81. The top plate portion 102 is disposed axially above the stator 20 and covers the open upper end of the side plate portion 103. The top plate portion 102 holds the bearing 82.

[0015] The bearings 81 and 82 support the shaft 11 rotatably relative to the housing 100. The bearings 81 and 82 may be ball bearings, for example.

[0016] The stator 20 is disposed radially outside the rotor 10 and is fixed to the housing 100. When the motor 1 is driven, torque is generated between the stator 20 and the magnet 13.

[0017] (2. Configuration of Stator) A stator according to an exemplary embodiment of the present invention will be described. FIG. 2 is a top view of the stator 20, and FIG. 3 is an enlarged perspective view of a portion of the stator 20. Note that the coils C are not shown in FIG. 3. Also, FIG. 4 is a perspective view of the teeth 212. The stator 20 includes a stator core 21 and the coils C.

[0018] The stator core 21 has an annular core back 211 surrounding the central axis J and teeth 212, and is formed by connecting a plurality of teeth 212 to the core back 211. For example, in this embodiment, the number of teeth 212 is 18. The core back 211 and each tooth 212 are formed by stacking a plurality of magnetic materials, such as electromagnetic steel sheets, in the axial direction. The core back 211 has a plurality of through holes 211a that penetrate radially and are arranged circumferentially. The through holes 211a are arranged at equal intervals circumferentially, and in this embodiment, 18 of them are formed. Each tooth 212 has a protrusion 212a that protrudes radially outward from its radial outer end and is arranged inside the through hole 211a. Each tooth 212 extends radially inward from the core back, and the tip of each tooth has an umbrella portion that extends circumferentially.

[0019] The coils C are formed by conductors 22 wound around each tooth 212. The conductors 22 are covered with an insulating coating, and adjacent conductors 22 are insulated from each other. The coils C are arranged circumferentially in the order of U-phase, V-phase, and W-phase, for example, and coils of the same phase are not adjacent to each other in the circumferential direction. By having circumferentially adjacent coils C of different phases, rotational irregularities of the rotor 10 can be suppressed and vibration of the rotor 10 can be reduced.

[0020] For example, the conductor wire 22 of the coil C shown in FIG. 5 is a rectangular wire.

[0021] The coil C is constructed by winding a rectangular wire. This allows for a higher space factor for the coil C than when a round wire is used. In this specification, "rectangular wire" refers to a wire having a rectangular or substantially rectangular cross section. In this specification, "substantially rectangular" includes a rectangular shape with rounded corners. Although not shown in the drawings, the rectangular wire that constitutes the coil C in this embodiment is an enameled wire having an enamel coating on its surface.

[0022] The coil C includes a pair of axially extending portions 43 that extend in the axial direction of the central axis (J) on both circumferential sides of the tooth 212 to which the coil C is attached. The pair of axially extending portions 43 circumferentially sandwich the tooth 212. The axially extending portions 43 are formed by bundling together multiple pieces of flat wire that make up the coil C. The contour shape of the axially extending portions 43 in a cross section perpendicular to the axial direction of the central axis (J) is, for example, a fan shape whose circumferential dimension decreases from the core back 211 toward the tip of the tooth 212.

[0023] Furthermore, in the contour shape of the axially extending portion 23 of the coil C, the radial dimension of each rectangular wire gradually increases from the core back 211 toward the tip of the tooth 212.

[0024] After the winding process and before insertion into the teeth (before step S1 in FIG. 6), the axially extending portion 23 of the coil C is pressed to compress and deform the coil into a fan shape.

[0025] Furthermore, when the contour shape of the axially extending portion of the coil C is made fan-shaped, the circumferential dimension decreases as one moves from the core back 211 to the tip of the teeth 212, and the radial dimension increases. This reduces the amount of deformation of the flat wire when the coil is compressed by press processing the flat wire, thereby preventing the enamel coating on the surface of the flat wire from breaking and preventing the flat wire from deforming unevenly.

[0026] In this specification, the term "fan-shaped" includes a shape surrounded by two arcs with the same center of curvature but different radii, and two line segments extending in the radial direction of a circle centered on the center of curvature and connecting the two ends of the two arcs. Furthermore, in this specification, the term "fan-shaped" includes both a strict fan-shaped shape and an approximate fan-shaped shape. In this specification, the term "approximate fan-shaped" includes a shape in which the arcs of the fan shape are approximated by multiple line segments. In this embodiment, the contour shape of the axially extending portion 43 in a cross section perpendicular to the axial direction is a shape surrounded by the two arcs and two line segments described above.

[0027] The coil C includes a first winding body 24 and a second winding body 25, each of which is formed by winding a rectangular wire. In Fig. 5, the first winding body 24 constitutes the radially inner portion of the coil C, and the second winding body 25 constitutes the radially outer portion of the coil C. In other words, the second winding body 25 is located radially outward from the first winding body 24.

[0028] 5 , the first winding body 24 and the second winding body 25 are each three-layer windings wound in two aligned rows aligned in the radial direction. This results in a total number of turns of the coil C of 12. In other words, when N is an integer equal to or greater than 1 and M is an integer greater than N, the first winding body 24 and the second winding body 25 are M-layer windings wound in N aligned rows aligned in the radial direction. This allows the total number of turns of the coil C to be suitably increased, thereby improving motor efficiency.

[0029] 10, one end 24a of the rectangular wire constituting the first winding body 24 has a substantially rectangular cross-sectional shape, while one end 25a of the rectangular wire constituting the second winding body 25 has a substantially square cross-sectional shape. One end 24a of the rectangular wire constituting the first winding body 24 and one end 25a of the rectangular wire constituting the second winding body 25 sandwich a transition section 26 having a substantially circular cross-sectional shape therebetween, forming a continuous winding bridge section 27. As a result, the first winding body 24 and the second winding body 25 are connected in series to form a single coil C.

[0030] In this way, the coil C is formed from a single continuous piece of flat wire having different cross-sectional shapes, so there is no need to connect one end of the first winding body 24 and one end of the second winding body 25 by joining. Compared to connecting by joining, in this embodiment it is possible to significantly reduce the number of joints required for coil connection, thereby improving the productivity of the coil C.

[0031] Furthermore, the winding transition portion 27 has an approximately rectangular cross-sectional shape at one end 24a, which gradually changes to an approximately circular cross-sectional shape toward the transition portion 26, which has an approximately circular cross-sectional shape, and then from the transition portion 26 toward the one end 25a, which has an approximately square cross-sectional shape, the cross-sectional shape gradually changes to an approximately square, and the coil C is formed from a single continuous flat wire having different cross-sectional shapes.

[0032] Furthermore, the cross-sectional area of ​​the winding cross-section 27 at one end 24a of the first winding body 24 and the cross-sectional area of ​​the cross-section at one end 25a of the second winding body 25 are approximately equal, but the size of the cross-sectional area may be changed as appropriate.

[0033] The cross-sectional shape of the rectangular wire constituting the first winding body 24 of the axially extending portion 23 of the coil C shown in Fig. 5 is, for example, a rectangular shape with rounded corners, and the cross-sectional shape of the rectangular wire constituting the second winding body 25 is, for example, a square shape with rounded corners.

[0034] The ends of the conducting wire 22 wound around each tooth 212 extend axially downward and are connected to a circuit board (not shown) held on the bottom plate portion 101. When a drive current is supplied to the coil C, a magnetic field is generated, and this magnetic field causes the rotor 10 to rotate.

[0035] Eighteen coils C are provided corresponding to the teeth 212, and are connected in a ring shape to form a unit. At this time, multiple coils C of the same phase are connected via crossover wires (not shown) extending in the circumferential direction. After the unitized coils C are placed inside the core back 211, the teeth 212 are inserted.

[0036] The protrusions 212a of the teeth 212 are disposed inside the through holes 211a, and the teeth 212 are fixed to the core back 211. This allows for easy assembly of the stator 20. The protrusions 212a are welded to the peripheral wall of the through holes 211a from the radially outer side of the core back 211. This allows for easy fixing of each tooth 212 to the core back 211. This makes it possible to provide a stator 20 that can improve assembly workability and strength. Examples of welding include laser welding.

[0037] The radially outer end of each tooth 212 is in surface contact with the inner peripheral surface of the core back 211. The surface contact between each tooth 212 and the core back 211 improves the radial dimensional accuracy when attaching the teeth 212 to the inner peripheral surface of the core back 211. In addition, the surface contact between the core back 211 and the teeth 212 allows magnetic flux to flow smoothly between the core back 211 and the teeth 212.

[0038] The core back 211 has a plurality of grooves 211b. The grooves 211b are recessed radially inward from the outer peripheral surface of the core back 211 and extend axially through the through holes 211a. In addition, in a cross section perpendicular to the axial direction, a pair of inner side surfaces 211c facing each other in the circumferential direction of the grooves 211b narrow in the circumferential direction as they extend radially outward (see FIG. 5). That is, in a cross section perpendicular to the axial direction, the circumferential width W of the grooves 211b is formed to decrease radially outward.

[0039] The core back 211 is easily formed by fitting a jig into the groove 211b and stacking annular electromagnetic steel sheets in the axial direction. At this time, a pair of circumferentially opposing inner surfaces 211c narrow in the circumferential direction as they extend radially outward, making it difficult for the jig to come out radially outward from the groove 211b. Therefore, the electromagnetic steel sheets can be stacked with high precision to form the core back 211. After the electromagnetic steel sheets have been stacked, the jig can be easily removed axially along the groove 211b.

[0040] (3. Structure of First Resin and Second Resin) FIG. 5 is an enlarged cross-sectional view showing a portion of the stator 20, the cross-section being perpendicular to the central axis J. The stator 20 further has a first resin 41 and a second resin 42. The first resin 41 is interposed between the conductive wires 22 that constitute each coil C. The second resin 42 is interposed at least either between the coil C and the core back 211 or between the coil C and the teeth 212. In this embodiment, the second resin 42 is interposed both between the coil C and the core back 211 and between the coil C and the teeth 212.

[0041] The first resin 41 and the second resin 42 are cured resins having insulating properties. The viscosity of the first resin 41 before curing is lower than the viscosity of the second resin 42 before curing. The second resin 42 has adhesive properties.

[0042] A one-component thermosetting resin can be suitably used as the first resin 41 and the second resin 42, and a low-halogen compatible resin that cures at a low temperature (90 to 150°C) and has high heat resistance (Tg 260 to 350°C) is preferred. However, this is not a limitation, and these resins do not have to be low-halogen compatible resins.

[0043] Heat generated in the coil C is efficiently transferred to the core back 211 and the teeth 212 via the second resin 42, thereby improving the heat dissipation of the stator 20. Heat generated in the coil C is also efficiently transferred between the conductive wires 22 via the first resin 41, thereby further improving the heat dissipation of the stator 20. In this embodiment, the second resin 42 is interposed both between the coil C and the core back 211 and between the coil C and the teeth 212, but it may be interposed only in one of these locations.

[0044] The gaps between the conductive wires 22 that make up the coil C are narrower than the gaps between the coil C and the core back 211, and are also narrower than the gaps between the coil C and the teeth 212. The first resin 41 has a low viscosity before hardening, so it easily flows into narrow gaps. Therefore, the first resin 41 can be caused to flow into the entire gaps between the conductive wires 22, further improving heat dissipation.

[0045] In this embodiment, the conductive wires 22 have a generally rectangular cross section perpendicular to the extension direction. This narrows the gap between adjacent conductive wires 22, increasing the capillary force in the gap. Therefore, the first resin 41 before hardening remains in the gap due to capillary action, and is less likely to drip from the lower end of the gap in the axial direction.

[0046] The second resin 42 has adhesive properties, and the coil C is adhered to the teeth 212 and the core back 211 via the second resin 42, and is stably fixed to the stator core 21. This prevents the coil C from vibrating when the rotor 10 rotates.

[0047] Note that a portion of the first resin 41 may be interposed between the coil C and the core back 211 or between the coil C and the teeth 212, and a portion of the second resin 42 may be interposed in the gaps between the conductive wires 22 that make up the coil C. In this case, the first resin 41 and the second resin 42 may be in contact with each other. This allows heat generated in the coil C to be efficiently transferred to the stator core 21 via the first resin 41 and the second resin 42. This further improves the heat dissipation performance of the stator 20.

[0048] 6 is a flowchart showing the manufacturing process of the stator 20. The manufacturing method of the stator 20 includes a coil mounting process, a teeth mounting process, a first flow-in process, and a second flow-in process. The second flow-in process may be performed before the first flow-in process.

[0049] In the coil mounting process, the coil C, which is connected in a circular shape and formed into a unit, is placed inside the core back 211 (step S1).

[0050] In the tooth attachment process, the teeth 212 are inserted into the coils C, and the protrusions 212a are positioned inside the through-holes 211a. Next, the protrusions 212a are welded to the peripheral walls of the through-holes 211a from the radially outer side of the core back 211 (step S2). This makes it possible to easily fix each tooth 212 to the core back 211.

[0051] In the first flowing step, the first resin 41 is dripped and flowed between the conductive wires 22 that make up the coil C. This allows the first resin 41 to easily flow into all the gaps between the conductive wires 22, improving the manufacturing efficiency of the stator 20.

[0052] In the second flowing step, the second resin 42 is dripped and flowed between the coil C and the core back 211 and between the coil C and the teeth 212. This allows the second resin 42 to easily flow entirely between the coil C and the core back 211 and entirely between the coil C and the teeth 212, further improving the manufacturing efficiency of the stator 20. In the present embodiment, the second resin 42 is dripped and flowed both between the coil C and the core back 211 and between the coil C and the teeth 212, but it may also be dripped and flowed only between the coil C and the core back 211 or between the coil C and the teeth 212.

[0053] Second Embodiment Next, a second embodiment of the present invention will be described. Fig. 7 is an enlarged perspective view of a portion of the stator 20, and the coil C is not shown in Fig. 7. For ease of explanation, the same reference numerals are used for parts that are the same as those in the first embodiment shown in Figs. 1 to 6 described above. The second embodiment differs from the first embodiment in that a plurality of through holes 211a are arranged in the axial direction and a plurality of protrusions 212a are arranged in the axial direction at the radially outer end of each tooth 212, and each protrusion 212a is arranged inside the through hole. The other parts are the same as those in the first embodiment.

[0054] In this embodiment, two through holes 211a are arranged side by side in the axial direction, and two protrusions 212a are arranged in the axial direction at the radially outer end of each tooth 212. This allows the teeth 212 and the core back 211 to be fixed more firmly.

[0055] Third Embodiment Next, a third embodiment of the present invention will be described. Fig. 8 is a vertical cross-sectional view schematically showing a motor 1 according to a third embodiment of the present invention, and Fig. 9 is a perspective view schematically showing a mounting member 120 of the motor 1. For ease of explanation, the same parts as those in the first embodiment shown in Figs. 1 to 6 are denoted by the same reference numerals. In the third embodiment, the fixing structure between the shaft 11 and the magnet holder 12 differs from that of the first embodiment. The other parts are the same as those of the first embodiment.

[0056] In this embodiment, the shaft 11 has a protrusion 111 and a shaft groove 112. The protrusion 111 is disposed axially below (on one axial side of) the magnet holder 12 and protrudes radially outward from the outer circumferential surface of the shaft 11. In this embodiment, the protrusion 111 extends circumferentially and is annular.

[0057] The shaft groove 112 is disposed on the axially upper side (the other axial side) of the magnet holder 12, and extends circumferentially while being recessed radially inward from the outer circumferential surface of the shaft 11. In the present embodiment, the shaft groove 112 is annular.

[0058] When fixing the shaft 11 and magnet holder 12, the shaft 11 is inserted into the insertion hole 12a of the magnet holder 12 from below (the other axial side) so that the magnet holder 12 comes into contact with the protrusion 111. Next, the mounting member 120 is inserted from above (one axial side) of the shaft 11 and placed in the shaft groove 112. This causes the mounting member 120 to fit into and be fixed in the shaft groove 112. Therefore, the magnet holder 12 is sandwiched in the axial direction between the mounting member 120 and the protrusion 111 and fixed to the shaft 11. This improves the ease of assembly of the motor 1.

[0059] The protrusion 111 is annular and extends circumferentially, and the magnet holder 12 is stably supported in the axial direction by the protrusion 111. This allows the magnet holder 12 to be firmly fixed to the shaft 11 in the axial direction. Note that the protrusion 111 does not have to be annular. For example, a plurality of protrusions 111 may be arranged side by side in the circumferential direction.

[0060] Furthermore, forming the shaft groove 112 in an annular shape improves the fit strength between the mounting member 120 and the shaft groove 112. This allows the magnet holder 12 to be stably supported in the axial direction by the mounting member 120. Therefore, the magnet holder 12 is more firmly fixed to the shaft 11 in the axial direction. Note that the shaft groove 112 does not have to be annular, and can be formed according to the shape of the mounting member 120.

[0061] The mounting member 120 is an annular metal member and may have a notch 120a cut out from a portion thereof. By forming the mounting member 120 in a C-ring shape, the two parts expand in directions away from each other across the notch. This allows the mounting member 120 to be easily inserted into the shaft 11 even when the mounting member 120 has an inner diameter smaller than the outer diameter of the shaft 11.

[0062] Alternatively, the mounting member 120 may be formed in an E-ring shape by increasing the circumferential width of the notch 120a. In this case, the mounting member 120 can be fitted onto the shaft 11 from the radially outer side. This allows the mounting member 120 to be easily attached to the shaft 11.

[0063] In the present embodiment, the shaft 11 further includes a recess 113. The recess 113 is disposed between the protrusion 111 and the shaft groove 112 in the axial direction, and is recessed radially inward from the outer circumferential surface around the entire circumference of the shaft 11.

[0064] Additionally, a tolerance ring 130 is disposed between the shaft 11 and the magnet holder 12. The tolerance ring 130 is a cylindrical metal member disposed in the recess 113. The tolerance ring 130 has multiple protrusions (not shown) that protrude from the outer circumferential surface and are aligned in the circumferential direction. The protrusions are crushed when the shaft 11 is inserted into the insertion hole 12a of the magnet holder 12. This more firmly secures the shaft 11 and the magnet holder 12 together. Therefore, the magnet holder 12 can be prevented from shifting in the circumferential direction relative to the shaft 11 when the motor 1 is driven.

[0065] <Others> The above-described embodiment is merely an example of the present invention. The configuration of the embodiment may be appropriately modified without departing from the technical spirit of the present invention. Furthermore, the embodiments may be combined as far as possible. For example, three or more through holes 211a may be arranged in the axial direction, and three or more protrusions 212a may be arranged in the axial direction at the radially outer end of each tooth 212.

[0066] In addition, in the above embodiment, the teeth 212 are arranged circumferentially, extending radially inward from the core back 211, but they may be arranged circumferentially, extending radially outward from the core back 211. In this case, the magnets 13 are arranged radially outward from the teeth 212, thereby forming an outer rotor type motor 1.

[0067] <Additional Notes> As described above, a stator (20) according to one aspect of the present disclosure includes a stator core (21) having an annular core back (211) surrounding a central axis (J) and a plurality of teeth (212) extending radially inward from the core back and arranged in the circumferential direction, and a coil (C) formed of a conductor (22) wound around the teeth, wherein the core back has a plurality of through holes (211 a) penetrating radially and arranged in the circumferential direction, and each of the teeth has a protrusion (212 a) protruding radially outward from a radial outer end portion and arranged inside the through hole.

[0068] In the first configuration, the radially outer end of each of the teeth may be in surface contact with the inner peripheral surface of the core back (second configuration).

[0069] In addition, in the above-mentioned first or second configuration, the core back may have a groove portion (211b) that is recessed radially inward from the outer peripheral surface and extends axially through the through hole, and the groove portion may be configured such that, in a cross section perpendicular to the axial direction, a pair of inner surfaces (211c) that face each other circumferentially narrow in the circumferential direction as they move radially outward (third configuration).

[0070] Furthermore, in any of the above first to third configurations, the through holes may be arranged in multiple rows in the axial direction and multiple rows in the circumferential direction, and the protrusions may be arranged in multiple rows in the axial direction at the radial outer end of each tooth, and each may be arranged inside the through hole (fourth configuration).

[0071] Furthermore, a motor (1) according to one aspect of the present disclosure includes a stator having any one of the first to fourth configurations described above, and a rotor (10) that rotates around the central axis and faces the stator in the radial direction, wherein the rotor has a columnar shaft (11) extending along the central axis, a cylindrical magnet holder (12) having an insertion hole (12a) into which the shaft is inserted, and a plurality of magnets (13) arranged at the radially outer end of the magnet holder and arranged circumferentially, wherein the shaft has a protrusion (111) arranged on one axial side of the magnet holder and protruding radially outward from the outer circumferential surface, and a shaft groove (112) arranged on the other axial side of the magnet holder and recessed radially inward from the outer circumferential surface and extending circumferentially, and the magnet holder may be configured to be sandwiched in the axial direction between an annular mounting member (120) arranged in the shaft groove and the protrusion (fifth configuration).

[0072] In the fifth configuration, the protruding portion may be configured to extend in a circumferential direction and have an annular shape (sixth configuration).

[0073] In the fifth or sixth configuration, the shaft groove may be annular (seventh configuration).

[0074] In any one of the fifth to seventh configurations, the mounting member may have a notch (120a) in which a part of the mounting member is cut out in the circumferential direction (eighth configuration).

[0075] In addition, a stator (20) according to one aspect of the present disclosure comprises a stator core (21) having an annular core back (211) surrounding a central axis (J) and a plurality of teeth (212) extending radially from the core back and arranged circumferentially, and a coil (C) formed of a conductor (22) wound around the teeth, and has a first resin (41) interposed between the conductors constituting the coil, and a second resin (42) interposed at least between the coil and the core back and between the coil and the teeth (ninth configuration).

[0076] In the ninth configuration, the viscosity of the first resin before curing may be lower than the viscosity of the second resin before curing (tenth configuration).

[0077] In the ninth or tenth configuration, the first resin and the second resin may be in contact with each other (eleventh configuration).

[0078] In any one of the ninth to eleventh configurations, the conducting wire may have a substantially rectangular cross section perpendicular to the extending direction (twelfth configuration).

[0079] In any one of the ninth to twelfth configurations, the second resin may have adhesive properties (thirteenth configuration).

[0080] Furthermore, a motor (1) according to one aspect of the present disclosure may be configured to include a stator having any one of the ninth to thirteenth configurations described above, and a rotor (10) that is radially opposed to the stator and rotates around the central axis (fourteenth configuration).

[0081] In addition, a manufacturing method of a stator (20) according to one aspect of the present disclosure includes a stator core (21) having an annular core back (211) surrounding a central axis (J) and a plurality of teeth (212) extending radially from the core back and arranged circumferentially, and a coil (C) formed of a conductor (22) wound around the teeth, and includes a first flow-in process of dripping and flowing a first resin (41) between the conductors constituting the coil, and a second flow-in process of dripping and flowing a second resin (42) between the coil and the core back or between the coil and the teeth (15th configuration).

[0082] Furthermore, a stator (20) according to one aspect of the present disclosure includes a stator core (21) having an annular core back (211) surrounding a central axis (J) and a plurality of teeth (212) extending radially inward from the core back and arranged in a circumferential direction, and a coil (C) configured with a conductor (22) wound around the teeth, wherein the coil includes a first winding body (24) and a second winding body (25) located radially outward of the first winding body and connected to the first winding body via a winding crossover portion (27), where N is an arbitrary integer equal to or greater than 1 and M is an arbitrary integer greater than N, and the first winding body (24) and the second winding body (25) are winding bodies of M layers aligned in N rows arranged radially (16th configuration).

[0083] In addition, in the motor (1) according to one aspect of the present disclosure, in the sixteenth configuration, the conductor (22) is a rectangular wire (seventeenth configuration).

[0084] In addition, a motor (1) according to one aspect of the present disclosure, in the configuration of the 16th or 17th described above, is provided with a pair of axial extension portions (23) extending in the axial direction of the central axis (J) on both circumferential sides of the teeth (212), and the contour shape of the axial extension portions in a cross section perpendicular to the axial direction of the central axis (J) is a fan shape whose circumferential dimension decreases from the core back (211) toward the tip of the teeth (212) (configuration 18th).

[0085] In addition, in the motor (1) according to one aspect of the present disclosure, in the above-mentioned 18th configuration, in the contour shape of the axially extending portion (23) of the coil (C), the radial dimension of each flat wire gradually increases from the core back 211 toward the tip of the tooth 212 (19th configuration).

[0086] In addition, in the motor (1) according to one aspect of the present disclosure, in the above-mentioned 16th to 19th configurations, the winding crossover portion (27) of the coil (C) is formed as a single piece with one end (24a) of the rectangular wire constituting the first winding body (24) and one end (25a) of the rectangular wire constituting the second winding body (25) sandwiched between the transition portion (26) (20th configuration).

[0087] In addition, in the motor (1) according to one aspect of the present disclosure, in the above-mentioned 20th configuration, the cross section of one end (24a) of the flat wire constituting the first winding body (24) is rectangular, the cross section of the transition portion is circular, and the cross section of one end (25a) of the flat wire constituting the second winding body (25) is a regular rectangle (21st configuration).

[0088] In addition, in the motor (1) according to one aspect of the present disclosure, in the above-mentioned 20th or 21st configuration, the cross-sectional area of ​​one end (24a) of the rectangular wire constituting the first winding body (24) is equal to the cross-sectional area of ​​one end (25a) of the rectangular wire constituting the second winding body (25) (22nd configuration).

[0089] The motor of the present invention can be used in a variety of rotating machines.

[0090] DESCRIPTION OF SYMBOLS 1 Motor 10 Rotor 11 Shaft 11a Shaft flange portion 11b Flange screw hole 12 Magnet holder 12a Insertion hole 12b Holder screw hole 13 Magnet 14 Screw 20 Stator 21 Stator core 22 Conductor 23 Axial extension portion 24 First winding body 24a One end of rectangular wire constituting first winding body 25 Second winding body 25a One end of rectangular wire constituting second winding body 26 Transition portion 27 Winding crossover portion 41 First resin 42 Second resin 81, 82 Bearing 100 Housing 101 Bottom plate portion 102 Top plate portion 103 Side plate portion 111 Protrusion 112 Shaft groove portion 113 Recess 120 Mounting member 120a Cutout portion 130 Tolerance ring 211 Core back 211a Through hole 211b Groove portion 211c Inner surface 212 Teeth 212a Convex portion C Coil J Central axis W Width

Claims

1. A stator comprising: a stator core having an annular core back surrounding a central axis and a plurality of teeth extending radially inward from the core back and arranged circumferentially; and a coil formed of a conducting wire wound around the teeth, wherein the core back has a plurality of through holes that penetrate radially and are arranged circumferentially, and each of the teeth has a protrusion that protrudes radially outward from its radial outer end and is arranged inside the through hole.

2. The stator according to claim 1, wherein the radially outer end of each of the teeth is in surface contact with the inner peripheral surface of the core back.

3. A stator as set forth in claim 1 or claim 2, wherein the core back has a groove recessed radially inward from its outer peripheral surface and extending axially through the through hole, and wherein, in a cross section perpendicular to the axial direction, a pair of inner surfaces opposing each other in the circumferential direction of the groove narrows circumferentially as they extend radially outward.

4. A stator according to claim 1 or claim 2, wherein the through holes are arranged in a plurality of rows in the axial direction and in a plurality of rows in the circumferential direction, and the protrusions are arranged in a plurality of rows in the axial direction at the radial outer end of each of the teeth, and are each arranged inside the through hole.

5. A motor comprising: a stator as defined in claim 1 or 2; and a rotor that rotates about the central axis and faces the stator in the radial direction, wherein the rotor has: a columnar shaft extending along the central axis; a cylindrical magnet holder having an insertion hole into which the shaft is inserted; and a plurality of magnets that are arranged at the radially outer end of the magnet holder and are aligned circumferentially, wherein the shaft has: a protrusion that is arranged on one axial side of the magnet holder and protrudes radially outward from the outer circumferential surface; and a shaft groove that is arranged on the other axial side of the magnet holder and is recessed radially inward from the outer circumferential surface and extends circumferentially, wherein the magnet holder is sandwiched in the axial direction between an annular mounting member that is arranged in the shaft groove and the protrusion.

6. The motor according to claim 5, wherein the protrusion extends in the circumferential direction and is annular.

7. The motor of claim 5, wherein said shaft groove is annular.

8. The motor according to claim 5, wherein the mounting member has a notch in which a portion of the mounting member is cut out in the circumferential direction.

Images