rotating electrical machines

Abstract

To provide a rotary electric machine capable of suppressing the disconnection of winding and the occurrence of abnormal noises without deteriorating cogging torque performance.SOLUTION: A rotary electric machine 10 includes: a stator core 22; a cylindrical bobbin 53 fitted in teeth 52 of the stator core 22; and winding 23 wound on the bobbin 53. The stator core 22 includes: an annular back yoke 51; and the teeth 52 with constant-width protruding radially inward from the back yoke 51. The rotary electric machine 10 further includes a non-magnetic ring 64. The non-magnetic ring 64 is an annular member arranged concentrically with the back yoke 51 to support an inner end portion 63 of the bobbin 53 in the radial inner to restrict the radially inner movement of the bobbin 53.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a rotating electric machine. [Background technology]

[0002] Stators are known that are made by winding electric wire around a cylindrical bobbin to form a winding, and then inserting the bobbin into the teeth of a stator core. The stator disclosed in Patent Document 1 is made by arranging split cores, into which bobbins are inserted, in the circumferential direction, and press-fitting an outer ring and an inner ring into the split cores. The inner ring is integrally molded so that magnetic and non-magnetic portions are alternately arranged in the circumferential direction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-60859 Summary of the Invention [Problem to be solved by the invention]

[0004] If the bobbin inserted into the teeth moves radially, the winding may break or generate abnormal noise. In Patent Document 1, the inner ring restricts the bobbin from moving radially inward. However, because the magnetic portion of the inner ring forms the magnetic poles of the stator, low component precision and assembly precision of the inner ring will result in a decrease in cogging torque performance.

[0005] The present invention has been made in consideration of the above points, and its object is to provide a rotating electric machine that can suppress winding breakage and the occurrence of abnormal noise without degrading cogging torque performance. [Means for solving the problem]

[0006] The rotating electric machine of the present invention includes a stator core (22), a cylindrical bobbin (53) fitted onto teeth (52) of the stator core, and a winding (23) wound around the bobbin. The stator core has an annular back yoke (51) and teeth of a constant width or tapered shape protruding radially inward from the back yoke. The bobbin has a cylindrical portion (61), an outer end portion (62), and an inner end portion (63). The rotating electric machine further includes a non-magnetic ring (64) made of a non-magnetic metal. The non-magnetic ring is an annular member arranged concentrically with the back yoke and supports the inner end portion of the bobbin so as to restrict radially inward movement of the bobbin. The non-magnetic ring is disposed radially outward of the radially inner tip end surfaces (65) of the teeth and adjacent to the radially inner side of the inner end portion of the bobbin, and its axial end surface abuts against the axially outer surfaces of the teeth, forming a contact between the stator core and the housing (31). Separately It is provided.

[0007] The non-magnetic ring restricts the bobbin's radially inward movement, preventing winding breakage and noise caused by bobbin movement. In addition, because the ring that supports the bobbin is non-magnetic, cogging torque performance is not affected even if the non-magnetic ring's component precision or assembly precision is low. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a vertical cross-sectional view of a rotating electric machine according to a first embodiment. [Figure 2] Cross-sectional view of line II-II in Figure 1. [Figure 3] 2 is a diagram of the stator and non-magnetic ring of FIG. 1 as viewed from the control unit side, showing a cross section of a part of the inner side in the radial direction of the bobbin. FIG. [Figure 4] Enlarged view of part IV in Figure 1. [Figure 5] Enlarged view of part V in Figure 3. [Figure 6] FIG. 10 is a diagram of a stator and a non-magnetic ring according to a second embodiment as viewed from the control unit side, and corresponds to FIG. 3 of the first embodiment. [Figure 7] Enlarged view of part VII in Figure 6. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, several embodiments will be described with reference to the drawings. The same reference numerals will be used to designate substantially the same components among the embodiments, and the description thereof will be omitted.

[0010] [First embodiment] 1 and 2, the rotating electric machine 10 is an electromechanical integrated type in which the motor 20 and the control unit 40 are integrally provided. The control unit 40 controls the motor 20 to generate a desired torque based on information input from the outside and information such as the motor current detected inside the control unit 40. The torque of the motor 20 is output to the outside from the output end of the rotating shaft 26.

[0011] Hereinafter, a direction parallel to the rotation axis O of the motor 20 will be referred to as the axial direction. A direction perpendicular to the rotation axis O will be referred to as the radial direction. A direction around the rotation axis O will be referred to as the circumferential direction.

[0012] The control unit 40 is disposed on one side of the axial direction relative to the motor 20, and includes a circuit board 41, a cover 42, and a connector 43. The circuit board 41 is equipped with a rotation angle sensor 44 that detects the rotation angle of the motor 20, a motor drive element 45 that switches the energized state of the motor 20 by performing a switching operation, and a control circuit 46 that performs calculations based on various information and sends control signals to the motor drive element 45, etc.

[0013] The cover 42 is provided to cover the substrate 41 and is fixed to the housing 31 by, for example, adhesive. The connector 43 is for connecting the control unit 40 to the outside, and extends to the outside through an opening 47 in the cover 42.

[0014] Motor 20 is a three-phase brushless motor and includes a stator 21, a rotor 25, and a housing 31 that houses them. Stator 21 has a stator core 22 fixed to housing 31 and windings 23 assembled to stator core 22. Windings 23 are connected to control unit 40 by lead wires 24. Rotor 25 has a rotating shaft 26 supported by rear bearing 35 and front bearing 36, and a rotor core 27 fixed to rotating shaft 26. A permanent magnet 28 is provided on one end of rotating shaft 26.

[0015] The housing 31 has a cylindrical motor case 32, a rear end frame 33 provided at one end of the motor case 32, and a front end frame 34 provided at the other end of the motor case 32. The rear end frame 33 and the front end frame 34 are fastened to each other with bolts (not shown).

[0016] As shown in Figures 1 to 3, the stator core 22 has an annular back yoke 51 and a plurality of teeth 52 that protrude radially inward from the back yoke 51. The teeth 52 have a constant circumferential width. The stator core 22 is a laminated body formed by stacking thin plates of a magnetic material in the axial direction, and is an integral core that is not divided in the circumferential direction. A cylindrical resin bobbin 53 that serves as an insulator is fitted onto the teeth 52.

[0017] The bobbin 53 has a cylindrical portion 61 into which the teeth 52 are inserted, a flange-shaped outer end portion 62 formed on the radially outer side of the bobbin 53, and a flange-shaped inner end portion 63 formed on the radially inner side of the bobbin 53. The winding 23 is wound around the cylindrical portion 61 between the outer end portion 62 and the inner end portion 63, and then assembled to the teeth 52 together with the bobbin 53.

[0018] The rotating electric machine 10 further includes a non-magnetic ring 64. The non-magnetic ring 64 is an annular member that is arranged concentrically with the back yoke 51, i.e., on the rotation axis O. The non-magnetic ring 64 is provided adjacent to the radially inner side of the multiple inner end portions 63 that are arranged in the circumferential direction, and supports the inner end portions 63 so as to restrict radially inward movement of the bobbin 53.

[0019] The non-magnetic rings 64 are made of a non-magnetic metal such as stainless steel and are formed to have a thin radial thickness. One non-magnetic ring 64 is disposed on each axial side of the bobbin 53. Both the bobbin 53 and the non-magnetic rings 64 are disposed radially outward of the radially inner tip surfaces 65 of the teeth 52.

[0020] The inner end 63 has recesses 66 that are recessed radially outward on the axial side of the teeth 52, and claws 67 formed on the opposite side of the teeth 52 in the axial direction. The non-magnetic ring 64 is pressed axially while being guided by inclined surfaces 68 of the claws 67, causing it to bend radially and climb over the claws 67 to fit into the recesses 66 and be assembled to the bobbin 53. The claws 67 serve as retaining portions for preventing the non-magnetic ring 64 from slipping out. A bottom surface 69 of the recess 66 is formed in an arc shape that follows the shape of the non-magnetic ring 64. The bottom surface 69 serves as a support surface when the non-magnetic ring 64 supports the bobbin 53.

[0021] (effect) As described above, in the first embodiment, the rotating electric machine 10 includes the non-magnetic ring 64. The non-magnetic ring 64 is an annular member disposed concentrically with the back yoke 51, and supports the radially inner end portion 63 of the bobbin 53 so as to restrict radially inward movement of the bobbin 53. Because the non-magnetic ring 64 restricts radially inward movement of the bobbin 53, it is possible to suppress breakage of the winding 23 and the generation of abnormal noise due to movement of the bobbin 53. Furthermore, because the ring supporting the bobbin 53 is non-magnetic, low component precision or assembly precision of the non-magnetic ring 64 does not affect cogging torque performance.

[0022] In the first embodiment, the non-magnetic rings 64 are disposed on both axial sides of the bobbin 53. This allows the bobbin 53 to be supported in a well-balanced manner without any deviation in the axial direction.

[0023] In the first embodiment, the stator core 22 is an integrated core in which the back yoke 51 is not divided in the circumferential direction. This makes it possible to improve the deterioration of motor performance that occurs when the split cores are assembled together, which is an issue when the back yoke 51 is a split core divided in the circumferential direction.

[0024] Furthermore, in the first embodiment, the non-magnetic ring 64 is disposed radially outward from the radially inner tip end surfaces 65 of the teeth 52. This improves the degree of freedom in designing the magnetic circuit of the stator 21. In other words, by disposing the non-magnetic ring 64 between the stator 21 and the rotor 25, it is possible to avoid a deterioration in magnetic characteristics that would otherwise accompany an increase in the air gap.

[0025] [Second embodiment] 6 and 7 , in the second embodiment, the inner end portion 63 contacts the other inner end portion 63 adjacent thereto in the circumferential direction so as to restrict radially inward movement of the bobbin 53. Specifically, circumferential end faces 71 located on both circumferential sides of the inner end portion 63 are flat surfaces extending along the radial direction and are in surface contact with the circumferential end faces 71 of the other inner end portion 63 adjacent thereto in the circumferential direction. As a result, the other bobbins 53 receive the load when the bobbin 53 attempts to move radially inward, thereby reducing the load applied to the non-magnetic ring 64. This allows the rigidity of the non-magnetic ring 64 to be reduced, increasing the degree of freedom in designing the non-magnetic ring 64.

[0026] [Other embodiments] In other embodiments, the non-magnetic ring may have a shape with a part cut out in the circumferential direction, such as a C-shape. In short, it is sufficient for the non-magnetic ring to support all of the bobbins.

[0027] In other embodiments, the non-magnetic ring may be provided on only one side in the axial direction, as long as it is possible to restrict the bobbin from moving radially inward.

[0028] In another embodiment, the stator core may be a split core.

[0029] The present invention is not limited to the above-described embodiment, and can be implemented in various forms without departing from the spirit of the invention. [Explanation of symbols]

[0030] 10 rotating electric machine, 22 stator core, 23 winding, 51 back yoke, 52 Teeth, 53 Bobbin, 64 Non-magnetic ring.

Claims

1. a stator core (22) having an annular back yoke (51) and teeth (52) of a constant width or tapered shape protruding radially inward from the back yoke; a cylindrical bobbin (53) having a cylindrical portion (61), an outer end portion (62), and an inner end portion (63) and fitted onto the teeth; A winding (23) wound on the bobbin; a non-magnetic ring (64) made of a non-magnetic metal that is an annular member arranged concentrically with the back yoke and supports the inner end portion of the bobbin so as to restrict radially inward movement of the bobbin; Equipped with The non-magnetic ring is arranged radially outward of the radially inner tip surfaces (65) of the teeth, adjacent to the radially inner side of the inner end portion of the bobbin, and is arranged separately from the stator core and housing (31) with its axial end face abutting the axially outer side surfaces of the teeth.

2. 2. The rotating electric machine according to claim 1, wherein the non-magnetic rings are disposed on both axial sides of the bobbin.

3. 3. The rotating electric machine according to claim 1, wherein the stator core is an integral core in which the back yoke is not divided.

4. The rotating electric machine according to any one of claims 1 to 3, wherein the inner end portion is in contact with another inner end portion adjacent thereto in the circumferential direction so as to restrict radially inward movement of the bobbin.

5. A claw portion (67) protruding in the opposite direction to the outer end portion is formed on the tip side of the inner end portion of the bobbin, A rotating electric motor according to any one of claims 1 to 4, wherein the non-magnetic ring has an axial height smaller than that of the inner end portion and is sandwiched between the tooth and the surface of the claw portion facing the tooth.

Images