Stator assembly

Abstract

A stator assembly (1) comprises a housing (2) formed in a cylindrical shape and a stator (10) accommodated inside the housing. The stator is provided with a stator core (18) that has a plurality of teeth (28) and is press-fitted inside the housing, a winding (22) that has a plurality of winding parts (34) wound around the respective teeth, and an insulating structure (20, 60) for insulating the plurality of winding parts. The insulating structure has a second facing surface (36A, 60A, 60B) facing a first facing surface (6A, 4A) of the housing. At least one of the first facing surface and the second facing surface has a closing part (40, 70, 80, 90) that closes the portion between the first facing surface and the second facing surface.

Description

Stator Assembly CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on and claims the benefit of priority from Japanese Patent Application No. 2024-015746, filed February 5, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a stator assembly for a rotating electric machine.

[0003] Examples of stators that can be used in stator assemblies for rotating electrical machines include the following: JP 2010-045951 A discloses a stator (stator 1) that includes a plurality of teeth (teeth 4), insulators (insulating members 7) attached to the plurality of teeth, windings (windings 6) wound around the plurality of teeth via the insulators, and an insulator cover (insulating cover 9) that covers the windings from one axial side of the stator.

[0004] As a result of detailed studies by the inventors, the following problem was discovered. Specifically, some rotating electrical machines include a stator housed inside a cylindrical housing, and the housing and the stator form a stator assembly. The stator is fixed to the housing by, for example, press-fitting a stator core into the housing. However, when the stator core is press-fitted into the housing, burrs are generated from the stator core and the housing, and the burrs come into contact with the windings and scrape off the coating of the windings, which may result in poor insulation of the windings. Therefore, it is necessary to prevent burrs generated from the stator core and the housing from leaking out.

[0005] The present disclosure provides a stator assembly that can prevent burrs generated from the stator core and the housing from flowing out when the stator core is press-fitted into the housing.

[0006] One aspect of the present disclosure is a stator assembly comprising: a cylindrically formed housing; and a stator accommodated inside the housing, the stator having a plurality of teeth; a stator core pressed into the inside of the housing; a winding having a plurality of windings wound around each of the plurality of teeth; and an insulating structure that insulates the plurality of windings, wherein the insulating structure has a second opposing surface that faces a first opposing surface of the housing, and at least one of the first opposing surface and the second opposing surface has a blocking portion that blocks the space between the first opposing surface and the second opposing surface.

[0007] According to the present disclosure, a stator assembly is provided that can prevent burrs generated from the stator core and the housing from flowing out when the stator core is press-fitted into the housing.

[0008] 4 is an exploded perspective view of a stator assembly according to the first embodiment. FIG. 4 is a perspective view of a stator. FIG. 5 is a longitudinal sectional view of a stator assembly. FIG. 6 is an enlarged view of a portion A of FIG. 3. FIG. 7 is a perspective view of an insulator member. FIG. 8 is a side view of the insulator member. FIG. 9 is a plan view of the insulator member. FIG. 10 is a perspective view of an insulator. FIG. 11 is an explanatory view showing the configuration of an insulator and a rib. FIG. 12 is a perspective view of an insulator according to a second embodiment. FIG. 13 is an explanatory view showing the configuration of an insulator and a rib according to the second embodiment. FIG. 14 is an explanatory view showing the configuration of an insulator and a rib according to a third embodiment. FIG. 15 is an enlarged longitudinal sectional view of a main part of a stator assembly according to a fourth embodiment. FIG. 16 is a longitudinal sectional view showing a first modified example of a stator assembly according to the fourth embodiment. FIG. 17 is a longitudinal sectional view showing a second modified example of a stator assembly according to the fourth embodiment. FIG. 18 is a longitudinal sectional view showing a third modified example of a stator assembly according to the fourth embodiment. FIG. 19 is a longitudinal sectional view showing a fourth modified example of a stator assembly according to the fourth embodiment. FIG. 19 is a longitudinal sectional view showing a fifth modified example of a stator assembly according to the fourth embodiment.

[0009] First Embodiment First, a first embodiment of the present disclosure will be described.

[0010] As shown in Fig. 1, the stator assembly 1 according to the first embodiment includes a housing 2 and a stator 10. The housing 2 is formed in a cylindrical shape with a top, and has a top wall portion 4 and a peripheral wall portion 6. The stator 10 is accommodated inside the housing 2.

[0011] The stator 10 is a so-called split-core type stator. The basic configuration of a split-core type stator is described in Japanese Patent No. 5502115. The stator 10 is applied to an inner-rotor type brushless motor, which is an example of a rotating electric machine. That is, a rotor (not shown) is rotatably housed inside the stator 10, and the stator 10 and the rotor form a motor section of the brushless motor.

[0012] The stator 10 includes a plurality of stator components 12. The stator 10 has a U-phase, a V-phase, and a W-phase, and the number of the plurality of stator components 12 corresponds to the number of U-phase, V-phase, and W-phase. That is, the stator 10 includes a U-phase stator component 12, a V-phase stator component 12, and a W-phase stator component 12. The plurality of stator components 12 are integrated by being assembled together in the axial direction of the stator 10.

[0013] In each drawing, arrow A1 indicates one axial side of the stator 10, and arrow A2 indicates the other axial side of the stator 10. In the following description, the circumferential direction of the stator 10 refers to the direction around the axial direction of the stator 10. The axial direction of the stator 10 and the axial direction of the members that make up the stator 10 (for example, the stator core 18 and the insulator 20 described below) are the same direction. The circumferential direction of the stator 10 and the circumferential direction of the members that make up the stator 10 are the same direction.

[0014] As shown in FIG. 2 , the stator 10 includes a stator core 18, an insulator 20, and a winding 22. The stator core 18 is composed of a plurality of core members 24 divided in the circumferential direction of the stator core 18. Each core member 24 has a core back portion 26 and teeth portions 28. That is, the stator core 18 is composed of a plurality of core members 24 divided into a plurality of teeth portions 28. The core back portion 26 constitutes a yoke portion 30, which is the outer peripheral portion of the stator core 18. The yoke portion 30 is formed in an annular shape along the circumferential direction of the stator core 18. The teeth portions 28 extend from the core back portion 26 toward the radially inner side of the stator core 18.

[0015] The insulator 20 has a plurality of insulating portions 32 provided on each of the plurality of core members 24. Each insulating portion 32 is attached to the tooth portion 28 and the core back portion 26, and covers the surfaces of the tooth portion 28 and the core back portion 26. The winding 22 has a plurality of winding portions 34 wound around each of the plurality of tooth portions 28 via the insulator 20 (more specifically, each insulating portion 32). As an example, each winding portion 34 is wound around each tooth portion 28 using a concentrated winding method. Each winding portion 34 is insulated from the stator core 18 by the insulating portion 32. The insulator 20 is an example of an "insulating structure" in this disclosure.

[0016] As shown in FIGS. 3 and 4 , the stator 10 is accommodated inside the housing 2, and the stator core 18 is press-fitted into the housing 2 to fix the stator 10 to the housing 2. The insulator 20 has an opposing wall portion 36 disposed opposite an inner circumferential surface 6A of the housing 2. The opposing wall portion 36 is disposed radially outward of the stator 10 relative to the plurality of winding portions 34 and is formed in an annular shape along the circumferential direction of the insulator 20. When the stator 10 is accommodated inside the housing 2, the inner circumferential surface 6A of the housing 2 and the outer circumferential surface of the insulator 20 (specifically, the outer circumferential surface 36A of the opposing wall portion 36) face each other in the radial direction of the stator 10. The inner circumferential surface 6A of the housing 2 is an example of a “first opposing surface” in the present disclosure, and the outer circumferential surface of the insulator 20 (specifically, the outer circumferential surface 36A of the opposing wall portion 36) is an example of a “second opposing surface” in the present disclosure.

[0017] As described above, when the stator core 18 is press-fitted into the housing 2, burrs are generated on the stator core 18 and the housing 2, and the burrs come into contact with the windings 22, scraping off the coating of the windings 22, which may result in poor insulation of the windings 22. Therefore, it is necessary to prevent the burrs generated on the stator core 18 and the housing 2 from leaking out. Therefore, in the first embodiment, ribs 40 are formed on the outer peripheral surface of the insulator 20, and the ribs 40 prevent the burrs from leaking out. This will be described in detail below.

[0018] The rib 40 is formed on the outer peripheral surface 36A of the opposing wall portion 36 and extends along the circumferential direction of the insulator 20. As an example, the rib 40 is formed in an annular shape along the circumferential direction of the insulator 20. The rib 40 is located on one axial side of the stator 10 relative to the stator core 18. The rib 40 protrudes in a convex shape from the outer peripheral surface 36A of the opposing wall portion 36 toward the inner peripheral surface 6A of the housing 2. The rib 40 is provided between the inner peripheral surface 6A of the housing 2 and the outer peripheral surface 36A of the opposing wall portion 36, thereby blocking the gap between the inner peripheral surface 6A of the housing 2 and the outer peripheral surface 36A of the opposing wall portion 36. The rib 40 blocks the gap between the inner peripheral surface 6A of the housing 2 and the outer peripheral surface 36A of the opposing wall portion 36, thereby forming a closed space 38 between the rib 40 and the stator core 18.

[0019] As an example of the rib 40 blocking the gap between the inner circumferential surface 6A of the housing 2 and the outer circumferential surface 36A of the opposing wall portion 36, the rib 40 may be press-fitted into the inside of the housing 2, may be in zero-touch contact with the inner circumferential surface 6A of the housing 2, or may have a gap between it and the inner circumferential surface 6A of the housing 2. When the rib 40 has a gap between it and the inner circumferential surface 6A of the housing 2, the size of the gap is preferably such that burrs do not escape. The rib 40 is an example of a "blocking portion" in the present disclosure.

[0020] 5 to 7 , the insulating portions 32 of the same phase among the plurality of insulating portions 32 are connected by a connecting portion 42. The connecting portion 42 is formed in an annular shape. The insulating portions 32 and the connecting portion 42 of the same phase constitute an insulator member 44 of each phase.

[0021] As shown in Fig. 8 , the insulator 20 is formed by combining insulator members 44 of a plurality of phases. The opposing wall portion 36 has a plurality of side wall portions 46 provided on each of the plurality of insulating portions 32. The plurality of side wall portions 46 are divided in the circumferential direction of the insulator 20. The rib 40 has a plurality of rib portions 48 provided on each of the plurality of side wall portions 46. The plurality of rib portions 48 are divided in the circumferential direction of the insulator 20.

[0022] 9 , the multiple side wall portions 46 include a side wall portion 46 provided on the U-phase insulator member 44, a side wall portion 46 provided on the V-phase insulator member 44, and a side wall portion 46 provided on the W-phase insulator member 44. Hereinafter, when it is necessary to distinguish between the multiple side wall portions 46, the side wall portion 46 provided on the U-phase insulator member 44 will be referred to as a first side wall portion 46U, the side wall portion 46 provided on the V-phase insulator member 44 will be referred to as a second side wall portion 46V, and the side wall portion 46 provided on the W-phase insulator member 44 will be referred to as a third side wall portion 46W.

[0023] The plurality of rib portions 48 include rib portions 48 provided on the first side wall portion 46U, rib portions 48 provided on the second side wall portion 46V, and rib portions 48 provided on the third side wall portion 46W. Hereinafter, when it is necessary to distinguish between the plurality of rib portions 48, the rib portions 48 provided on the first side wall portion 46U will be referred to as first rib portions 48U, the rib portions 48 provided on the second side wall portion 46V will be referred to as second rib portions 48V, and the rib portions 48 provided on the third side wall portion 46W will be referred to as third rib portions 48W.

[0024] The second side wall portion 46V is located adjacent to the first side wall portion 46U, and the third side wall portion 46W is located adjacent to the second side wall portion 46V on the opposite side of the first side wall portion 46U. The multiple side wall portions 46 are configured such that the first side wall portion 46U, the second side wall portion 46V, and the third side wall portion 46W are repeatedly arranged in the circumferential direction of the insulator 20. Similarly, the multiple rib portions 48 are configured such that the first rib portion 48U, the second rib portion 48V, and the third rib portion 48W are repeatedly arranged in the circumferential direction of the insulator 20.

[0025] The second rib portion 48V is disposed offset in the axial direction of the insulator 20 with respect to the first rib portion 48U, and the third rib portion 48W is disposed offset with respect to the second rib portion 48V on the opposite side of the first rib portion 48U in the axial direction of the insulator 20. As an example, the second rib portion 48V is disposed offset to the other axial side of the insulator 20 with respect to the first rib portion 48U, and the third rib portion 48W is disposed offset to the other axial side of the insulator 20 with respect to the second rib portion 48V.

[0026] One end of the first rib portion 48U in the circumferential direction of the insulator 20 is a first portion 48Ua, and the other end of the first rib portion 48U in the circumferential direction of the insulator 20 is a second portion 48Ub. Similarly, one end of the second rib portion 48V in the circumferential direction of the insulator 20 is a first portion 48Va, and the other end of the second rib portion 48V in the circumferential direction of the insulator 20 is a second portion 48Vb. Similarly, one end of the third rib portion 48W in the circumferential direction of the insulator 20 is a first portion 48Wa, and the other end of the third rib portion 48W in the circumferential direction of the insulator 20 is a second portion 48Wb.

[0027] A widthwise dimension W1 of each rib portion 48 is larger than a widthwise dimension W2 of each side wall portion 46 (see FIG. 7 ). A first portion 48Ua of the first rib portion 48U terminates at an end 46Ua on one side of the first side wall portion 46U in the circumferential direction of the insulator 20, and a second portion 48Ub of the first rib portion 48U protrudes toward the other circumferential side of the insulator 20 beyond an end 46Ub on the other side of the first side wall portion 46U in the circumferential direction of the insulator 20.

[0028] Similarly, the first portion 48Va of the second rib portion 48V terminates at the end 46Va on one side of the second side wall portion 46V in the circumferential direction of the insulator 20, and the second portion 48Vb of the second rib portion 48V protrudes toward the other circumferential side of the insulator 20 beyond the end 46Vb on the other side of the second side wall portion 46V in the circumferential direction of the insulator 20.

[0029] Similarly, the first portion 48Wa of the third rib portion 48W terminates at the end 46Wa on one side of the third side wall portion 46W in the circumferential direction of the insulator 20, and the second portion 48Wb of the third rib portion 48W protrudes toward the other circumferential side of the insulator 20 beyond the end 46Wb on the other side of the third side wall portion 46W in the circumferential direction of the insulator 20.

[0030] The first portion 48Ua of the first rib portion 48U and the second portion 48Vb of the second rib portion 48V overlap in the circumferential direction of the insulator 20. Similarly, the first portion 48Va of the second rib portion 48V and the second portion 48Wb of the third rib portion 48W overlap in the circumferential direction of the insulator 20. Similarly, the second portion 48Ub of the first rib portion 48U and the first portion 48Wa of the third rib portion 48W overlap in the circumferential direction of the insulator 20.

[0031] The second portion 48Ub of the first rib portion 48U terminates at a position where it overlaps with the first portion 48Wa of the third rib portion 48W in the circumferential direction of the insulator 20, the second portion 48Vb of the second rib portion 48V terminates at a position where it overlaps with the first portion 48Ua of the first rib portion 48U in the circumferential direction of the insulator 20, and the second portion 48Wb of the third rib portion 48W terminates at a position where it overlaps with the first portion 48Va of the second rib portion 48V in the circumferential direction of the insulator 20.

[0032] The rib 40 has an axial rib portion 50. The axial rib portion 50 is provided between the second portion 48Ub of the first rib portion 48U and the first portion 48Wa of the third rib portion 48W in the axial direction of the insulator 20, and extends in the axial direction of the insulator 20. As an example, the axial rib portion 50 is formed integrally with the third rib portion 48W. Note that the axial rib portion 50 may be formed integrally with the first rib portion 48U. Alternatively, the axial rib portion 50 may have a portion formed integrally with the third rib portion 48W and a portion formed integrally with the first rib portion 48U.

[0033] Next, the effects of the first embodiment will be described.

[0034] As described above in detail, in the stator assembly 1 according to the first embodiment, the ribs 40 are formed on the outer peripheral surface of the insulator 20. The ribs 40 protrude convexly from the outer peripheral surface of the insulator 20 toward the inner peripheral surface 6A of the housing 2. Therefore, the ribs 40 can prevent burrs generated from the stator core 18 and the housing 2 when the stator core 18 is press-fitted into the housing 2 from flowing out. This prevents burrs from coming into contact with the windings 22 (specifically, the winding portion 34) and scraping off the coating of the windings 22, thereby preventing poor insulation of the windings 22.

[0035] Furthermore, because the ribs 40 can prevent burrs from escaping, press fitting can be used as a method for fixing the stator core 18 to the housing 2. This eliminates the need to shrink fit the housing 2 to the stator core 18, and therefore improves the productivity of the stator assembly 1 compared to shrink fitting.

[0036] Moreover, the rib 40 extends along the circumferential direction of the insulator 20. Therefore, it is possible to suppress the outflow of burrs along the circumferential direction of the insulator 20. In particular, since the rib 40 is formed in an annular shape along the circumferential direction of the insulator 20, it is possible to suppress the outflow of burrs along the entire circumference of the insulator 20.

[0037] Furthermore, the rib 40 is divided into a plurality of rib portions 48 provided on each of the plurality of side wall portions 46. This makes it possible to realize a divided structure that divides the insulator 20 into a plurality of insulator members 44, and ultimately a divided structure that divides the stator 10 into a plurality of stator constituent portions 12.

[0038] Furthermore, the first portion 48Ua of the first rib portion 48U and the second portion 48Vb of the second rib portion 48V overlap in the circumferential direction of the insulator 20. This makes it possible to prevent burrs from leaking out from between the first portion 48Ua of the first rib portion 48U and the second portion 48Vb of the second rib portion 48V.

[0039] Similarly, the first portion 48Va of the second rib portion 48V and the second portion 48Wb of the third rib portion 48W overlap in the circumferential direction of the stator 10. This makes it possible to prevent burrs from leaking out from between the first portion 48Va of the second rib portion 48V and the second portion 48Wb of the third rib portion 48W.

[0040] Similarly, the second portion 48Ub of the first rib portion 48U and the first portion 48Wa of the third rib portion 48W overlap in the circumferential direction of the stator 10. This makes it possible to prevent burrs from leaking out from between the second portion 48Ub of the first rib portion 48U and the first portion 48Wa of the third rib portion 48W.

[0041] The rib 40 also has an axial rib portion 50. The axial rib portion 50 is provided between the second portion 48Ub of the first rib portion 48U and the first portion 48Wa of the third rib portion 48W in the axial direction of the insulator 20, and extends in the axial direction of the insulator 20. Therefore, even if the second portion 48Ub of the first rib portion 48U and the first portion 48Wa of the third rib portion 48W are spaced apart in the axial direction of the insulator 20, the axial rib portion 50 can seal the gap between the second portion 48Ub of the first rib portion 48U and the first portion 48Wa of the third rib portion 48W. This makes it possible to prevent burrs from leaking out from between the second portion 48Ub of the first rib portion 48U and the first portion 48Wa of the third rib portion 48W.

[0042] In the first embodiment, the rib 40 may be provided on the peripheral wall portion 6 of the housing 2 , or may be provided on both the peripheral wall portion 6 of the housing 2 and the insulator 20 .

[0043] Second Embodiment Next, a second embodiment of the present disclosure will be described.

[0044] In the second embodiment, the configuration of the rib 40 is changed as follows compared to the first embodiment. That is, as shown in Figures 10 and 11, multiple rib portions 48 are provided at the same axial position of the insulator 20. Furthermore, each rib portion 48 has the same width as each side wall portion 46.

[0045] Even with this configuration, the rib 40 extends along the circumferential direction of the insulator 20, and therefore, it is possible to suppress the outflow of burrs along the circumferential direction of the insulator 20. In particular, the rib 40 is formed in an annular shape along the circumferential direction of the insulator 20, and therefore, it is possible to suppress the outflow of burrs along the entire circumference of the insulator 20.

[0046] Furthermore, the rib 40 is divided into a plurality of rib portions 48 provided on each of the plurality of side wall portions 46. This makes it possible to realize a divided structure that divides the insulator 20 into a plurality of insulator members 44, and ultimately a divided structure that divides the stator 10 into a plurality of stator constituent portions 12.

[0047] [Third embodiment]

[0048] Next, a third embodiment of the present disclosure will be described. In the third embodiment, the configuration of the rib 40 is modified as follows compared to the first embodiment. That is, as shown in Fig. 12 , the multiple side wall portions 46 are configured such that a first side wall portion 46U provided with a first rib portion 48U, a second side wall portion 46V provided with a second rib portion 48V, and a third side wall portion 46W provided with no rib 40 are repeatedly arranged in the circumferential direction of the insulator 20.

[0049] The portion of the first rib portion 48U in the circumferential direction of the insulator 20 from the center to one end thereof is the first portion 48Ua, and the other end of the first rib portion 48U in the circumferential direction of the insulator 20 is the second portion 48Ub. Similarly, the one end of the second rib portion 48V in the circumferential direction of the insulator 20 is the first portion 48Va, and the portion of the second rib portion 48V in the circumferential direction of the insulator 20 from the center to the other end thereof is the second portion 48Vb.

[0050] The first portion 48Ua of the first rib portion 48U protrudes toward one side of the circumferential direction of the insulator 20 more than the end portion 46Ua on one side of the first side wall portion 46U in the circumferential direction of the insulator 20, and the second portion 48Ub of the first rib portion 48U protrudes toward the other side of the circumferential direction of the insulator 20 more than the end portion 46Ub on the other side of the first side wall portion 46U in the circumferential direction of the insulator 20.

[0051] Similarly, the first portion 48Va of the second rib portion 48V protrudes toward one side of the circumferential direction of the insulator 20 more than the end portion 46Va on one side of the second side wall portion 46V in the circumferential direction of the insulator 20, and the second portion 48Vb of the second rib portion 48V protrudes toward the other side of the circumferential direction of the insulator 20 more than the end portion 46Vb on the other side of the second side wall portion 46V in the circumferential direction of the insulator 20.

[0052] The first portion 48Ua of the first rib portion 48U and the second portion 48Vb of the second rib portion 48V overlap in the circumferential direction of the insulator 20. Similarly, the first portion 48Va of the second rib portion 48V and the second portion 48Wb of the third rib portion 48W overlap in the circumferential direction of the insulator 20.

[0053] An end of the first portion 48Ua of the first rib portion 48U terminates at a central portion of the second side wall portion 46V in the circumferential direction of the insulator 20, and an end of the second portion 48Ub of the first rib portion 48U terminates at a central portion of the third side wall portion 46W in the circumferential direction of the insulator 20. Similarly, an end of the first portion 48Va of the second rib portion 48V terminates at a central portion of the third side wall portion 46W in the circumferential direction of the insulator 20, and an end of the second portion 48Vb of the second rib portion 48V terminates at a central portion of the first side wall portion 46U in the circumferential direction of the insulator 20.

[0054] This configuration can prevent burrs from leaking out from between the first portion 48Ua of the first rib portion 48U and the second portion 48Vb of the second rib portion 48V. Similarly, it can prevent burrs from leaking out from between the second portion 48Ub of the first rib portion 48U and the first portion 48Va of the second rib portion 48V.

[0055] Fourth Embodiment Next, a fourth embodiment of the present disclosure will be described.

[0056] In the fourth embodiment, the configuration of the stator 10 is changed as follows compared to the first embodiment. That is, as shown in FIG. 13 , the stator 10 has a molded resin portion 60. The molded resin portion 60 seals and insulates the plurality of winding portions 34. The molded resin portion 60 is an example of an "insulating structure" in the present disclosure.

[0057] An outer peripheral surface 60A of the molded resin portion 60 faces an inner peripheral surface 6A of the housing 2 in the radial direction of the stator 10. A rib 70 is formed on the outer peripheral surface 60A of the molded resin portion 60. The rib 70 extends along the circumferential direction of the stator 10. As an example, the rib 70 is formed in an annular shape along the circumferential direction of the stator 10. The rib 70 is located on one axial side of the stator 10 relative to the stator core 18. The rib 70 protrudes in a convex shape from the outer peripheral surface 60A of the molded resin portion 60 toward the inner peripheral surface 6A of the housing 2.

[0058] One surface 70A of the rib 70 in the axial direction of the insulator 20 is formed in a tapered shape. The rib 70 is provided between the inner circumferential surface 6A of the housing 2 and the outer circumferential surface 60A of the molded resin portion 60, thereby closing the gap between the inner circumferential surface 6A of the housing 2 and the outer circumferential surface 60A of the molded resin portion 60. The rib 70 closes the gap between the inner circumferential surface 6A of the housing 2 and the outer circumferential surface 60A of the molded resin portion 60, thereby forming a closed space 38 between the rib 70 and the stator core 18.

[0059] As an example of the rib 70 blocking the gap between the inner circumferential surface 6A of the housing 2 and the outer circumferential surface 60A of the molded resin portion 60, the rib 70 may be press-fitted into the inside of the housing 2, may be in zero-touch contact with the inner circumferential surface 6A of the housing 2, or may have a gap between it and the inner circumferential surface 6A of the housing 2. When the rib 70 has a gap between it and the inner circumferential surface 6A of the housing 2, the size of the gap is preferably such that burrs do not escape. The rib 70 is an example of a "blocking portion" in the present disclosure.

[0060] Even with this configuration, the ribs 70 can prevent burrs generated from the stator core 18 and the housing 2 from flowing out when the stator core 18 is press-fitted into the housing 2. This prevents burrs from coming into contact with the windings 22 (specifically, the winding portion 34) and scraping off the coating of the windings 22, thereby preventing poor insulation of the windings 22.

[0061] Furthermore, because the ribs 70 can prevent burrs from escaping, press fitting can be used as a method for fixing the stator core 18 to the housing 2. This eliminates the need to shrink fit the housing 2 to the stator core 18, and therefore improves the productivity of the stator assembly 1 compared to shrink fitting.

[0062] Moreover, the rib 70 extends along the circumferential direction of the stator 10. Therefore, it is possible to suppress the outflow of burrs along the circumferential direction of the insulator 20. In particular, since the rib 70 is formed in an annular shape along the circumferential direction of the stator 10, it is possible to suppress the outflow of burrs along the entire circumference of the stator 10.

[0063] As shown in Fig. 14, the rib 70 may be formed to have a rectangular cross section. Also, as shown in Fig. 15, the other surface 70B of the rib 70 in the axial direction of the insulator 20 may be formed to have a tapered shape.

[0064] 16 , the outer peripheral surface 60A of the molded resin portion 60 may be tapered so as to slope toward the inner peripheral surface 6A of the housing 2 toward the other axial side of the insulator 20. Also, as shown in FIG. 17 , the outer peripheral surface 60A of the molded resin portion 60 may be tapered so as to slope toward the inner peripheral surface 6A of the housing 2 toward one axial side of the insulator 20. A portion 80 of the tapered outer peripheral surface 60A of the molded resin portion 60 that faces the inner peripheral surface 6A of the housing 2 may close the gap between the outer peripheral surface 60A of the molded resin portion 60 and the inner peripheral surface 6A of the housing 2. The tapered portion 80 of the tapered outer peripheral surface 60A of the molded resin portion 60 that faces the inner peripheral surface 6A of the housing 2 is an example of a “closing portion” in the present disclosure.

[0065] Even with this configuration, it is possible to prevent burrs generated from the stator core 18 and the housing 2 from flowing out when the stator core 18 is press-fitted into the housing 2 .

[0066] 18 , in a configuration in which the back surface 4A of the top wall portion 4 of the housing 2 and the front surface 60B of the molded resin portion 60 face each other in the axial direction of the stator assembly 1, a convex rib 90 protruding toward the back surface 4A of the top wall portion 4 of the housing 2 may be formed on the front surface 60B of the molded resin portion 60. The rib 90 closes the gap between the back surface 4A of the top wall portion 4 of the housing 2 and the front surface 60B of the molded resin portion 60, thereby forming a closed space 38 in the path between the rib 90 and the stator core 18. The back surface 4A of the top wall portion 4 of the housing 2 is an example of a “first opposing surface” in the present disclosure, and the front surface 60B of the molded resin portion 60 is an example of a “second opposing surface” in the present disclosure. The rib 90 is an example of a “blocking portion” in the present disclosure.

[0067] Even with this configuration, the ribs 90 can prevent burrs generated from the stator core 18 and the housing 2 from flowing out when the stator core 18 is press-fitted into the housing 2 .

[0068] The rib 90 may be provided on the top wall portion 4 of the housing 2 , or may be provided on both the top wall portion 4 of the housing 2 and the molded resin portion 60 .

[0069] Furthermore, among the configurations described in the first to fourth embodiments, configurations that can be combined may be combined as appropriate.

[0070] The first to fourth embodiments of the present disclosure have been described above, but the present disclosure is not limited to the above, and it goes without saying that various modifications can be made without departing from the spirit of the present disclosure.

[0071] The following supplementary notes are disclosed regarding the present disclosure: (Supplementary Note 1) A stator assembly (1) comprising: a cylindrical housing (2); and a stator (10) accommodated inside the housing, wherein the stator comprises: a stator core (18) having a plurality of teeth (28) and press-fitted inside the housing; a winding (22) having a plurality of winding portions (34) wound around each of the plurality of teeth; and an insulating structure (20, 60) that insulates the plurality of winding portions, wherein the insulating structure has a second opposing surface (36A, 60A, 60B) that faces a first opposing surface (6A, 4A) of the housing, and at least one of the first opposing surface and the second opposing surface has a blocking portion (40, 70, 80, 90) that blocks a gap between the first opposing surface and the second opposing surface. (Supplementary Note 2) The stator assembly according to Supplementary Note 1, wherein the first opposing surface is an inner peripheral surface (6A) of the housing, and the second opposing surface is an outer peripheral surface (36A, 60A) of the insulating structure. (Supplementary Note 3) The stator assembly according to Supplementary Note 2, wherein the insulating structure has an insulator (20) attached to the plurality of teeth portions and insulating the plurality of winding portions from the stator core, the insulator has an opposing wall portion (36) disposed opposite the inner peripheral surface of the housing, the outer peripheral surface of the insulating structure is the outer peripheral surface (36A) of the opposing wall portion, and the blocking portion is a rib (40) formed on the outer peripheral surface of the opposing wall portion and extending along the circumferential direction of the stator. (Appendix 4) A stator assembly as described in Appendix 3, wherein the stator core has a plurality of core members (24) divided into each of the plurality of tooth portions, the insulator has a plurality of insulating portions (32) provided on each of the plurality of core members, the opposing wall portion has a plurality of side wall portions (46) provided on each of the plurality of insulating portions, and the ribs are provided on the plurality of side wall portions and are divided in the circumferential direction of the stator.(Appendix 5) The stator assembly according to Appendix 4, wherein the rib has a plurality of rib portions (48) divided in the circumferential direction of the stator, the plurality of rib portions having: a first rib portion (48U) provided on a first side wall portion (46U) of the plurality of side wall portions; and a second rib portion (48V) provided on a second side wall portion (46V) of the plurality of side wall portions located adjacent to the first side wall portion and shifted in the axial direction of the stator relative to the first rib portion, and a first portion (48Ua) of the first rib portion and a second portion (48Vb) of the second rib portion overlap in the circumferential direction of the stator. (Appendix 6) The stator assembly described in Appendix 5, wherein the plurality of rib portions are provided on a third side wall portion (46W) located adjacent to the second side wall portion on the opposite side from the first side wall portion, and has a third rib portion (48W) arranged offset from the second rib portion on the opposite side from the first rib portion in the axial direction of the stator, the plurality of rib portions are configured such that the first rib portion, the second rib portion, and the third rib portion are repeatedly arranged in the circumferential direction of the stator, a first portion (48Va) of the second rib portion and a second portion (48Wb) of the third rib portion overlap in the circumferential direction of the stator, and a second portion (48Ub) of the first rib portion and a first portion (48Wa) of the third rib portion overlap in the circumferential direction of the stator. (Appendix 6) The stator assembly described in Appendix 5, wherein the plurality of rib portions are provided on a third side wall portion (46W) located adjacent to the second side wall portion on the opposite side from the first side wall portion with respect to the second side wall portion, and has a third rib portion (48W) arranged offset from the second rib portion on the opposite side from the first rib portion in the axial direction of the stator. (Supplementary Note 7) The stator assembly according to Supplementary Note 6, wherein the rib is provided between a second portion (48Ub) of the first rib portion and a first portion (48Wa) of the third rib portion in the axial direction of the stator, and has an axial rib portion (50) extending in the axial direction of the stator. (Supplementary Note 8) The stator assembly according to Supplementary Note 5, wherein the plurality of side wall portions are configured such that a first side wall portion (46U) on which the first rib portion is provided, a second side wall portion (46V) on which the second rib portion is provided, and a third side wall portion (46W) on which the rib is not provided are repeatedly arranged in the circumferential direction of the stator, and the second portion (48Ub) of the first rib portion and the first portion (48Va) of the second rib portion overlap in the circumferential direction of the stator.(Supplementary Note 9) The stator assembly according to Supplementary Note 4, wherein the rib has a plurality of rib portions (48) divided in the circumferential direction of the stator, and the plurality of rib portions are provided at the same position in the axial direction of the stator. (Supplementary Note 10) The stator assembly according to any one of Supplementary Notes 2 to 9, wherein the insulating structure has a molded resin portion (60) that seals the plurality of winding portions, an outer peripheral surface of the insulating structure is an outer peripheral surface (60A) of the molded resin portion, and the blocking portion is a rib (70) formed on the outer peripheral surface of the molded resin portion and extending along the circumferential direction of the stator.

Claims

1. A stator assembly (1) comprising: a cylindrical housing (2); and a stator (10) accommodated inside the housing, wherein the stator comprises: a stator core (18) having a plurality of teeth (28) and press-fitted inside the housing; a winding (22) having a plurality of windings (34) wound around each of the plurality of teeth; and an insulating structure (20, 60) that insulates the plurality of windings, wherein the insulating structure has a second opposing surface (36A, 60A, 60B) that faces a first opposing surface (6A, 4A) of the housing, and at least one of the first opposing surface and the second opposing surface has a blocking portion (40, 70, 80, 90) that blocks the gap between the first opposing surface and the second opposing surface.

2. A stator assembly according to claim 1, wherein the first opposing surface is an inner peripheral surface (6A) of the housing, and the second opposing surface is an outer peripheral surface (36A, 60A) of the insulating structure.

3. A stator assembly as set forth in claim 2, wherein the insulating structure has insulators (20) attached to the plurality of teeth and insulating the plurality of winding portions from the stator core, the insulators have opposing wall portions (36) arranged opposite the inner peripheral surface of the housing, the outer peripheral surface of the insulating structure is the outer peripheral surface (36A) of the opposing wall portion, and the blocking portion has a rib (40) formed on the outer peripheral surface of the opposing wall portion and extending circumferentially of the stator.

4. A stator assembly as set forth in claim 3, wherein the stator core has a plurality of core members (24) divided into each of the plurality of teeth, the insulator has a plurality of insulating sections (32) provided on each of the plurality of core members, the opposing wall section has a plurality of side wall sections (46) provided on each of the plurality of insulating sections, and the ribs are provided on the plurality of side wall sections and are divided in the circumferential direction of the stator.

5. A stator assembly as set forth in claim 4, wherein the rib has a plurality of rib portions (48) divided in the circumferential direction of the stator, the plurality of rib portions having: a first rib portion (48U) provided on a first side wall portion (46U) of the plurality of side wall portions; and a second rib portion (48V) provided on a second side wall portion (46V) of the plurality of side wall portions located adjacent to the first side wall portion and displaced in the axial direction of the stator relative to the first rib portion, and wherein a first portion (48Ua) of the first rib portion and a second portion (48Vb) of the second rib portion overlap in the circumferential direction of the stator.

6. A stator assembly as set forth in claim 5, wherein the plurality of rib portions are provided on a third side wall portion (46W) of the plurality of side wall portions that is located adjacent to the second side wall portion on the opposite side from the first side wall portion, and has a third rib portion (48W) that is shifted relative to the second rib portion on the opposite side from the first rib portion in the axial direction of the stator, the plurality of rib portions are configured so that the first rib portion, the second rib portion, and the third rib portion are repeatedly arranged in the circumferential direction of the stator, a first portion (48Va) of the second rib portion and a second portion (48Wb) of the third rib portion overlap in the circumferential direction of the stator, and a second portion (48Ub) of the first rib portion and a first portion (48Wa) of the third rib portion overlap in the circumferential direction of the stator.

7. A stator assembly as set forth in claim 6, wherein the rib has an axial rib portion (50) that is provided between the second portion (48Ub) of the first rib portion and the first portion (48Wa) of the third rib portion in the axial direction of the stator and extends in the axial direction of the stator.

8. A stator assembly as described in claim 5, wherein the plurality of side wall portions are configured such that a first side wall portion (46U) provided with the first rib portion, a second side wall portion (46V) provided with the second rib portion, and a third side wall portion (46W) not provided with the rib are repeatedly arranged in the circumferential direction of the stator, and the second portion (48Ub) of the first rib portion and the first portion (48Va) of the second rib portion overlap in the circumferential direction of the stator.

9. A stator assembly according to claim 4, wherein the rib has a plurality of rib portions (48) divided in the circumferential direction of the stator, and the plurality of rib portions are provided at the same position in the axial direction of the stator.

10. A stator assembly as claimed in any one of claims 2 to 9, wherein the insulating structure has a molded resin part (60) that seals the plurality of winding parts, the outer peripheral surface of the insulating structure is the outer peripheral surface (60A) of the molded resin part, and the blocking part has a rib (70) formed on the outer peripheral surface of the molded resin part and extending along the circumferential direction of the stator.

Images