Rotating Electric Machine

Abstract

To provide a rotary electric machine for a vehicle capable of suppressing iron loss while maintaining coupling force for coupling a plurality of electromagnetic steel sheets to each other.SOLUTION: Due to press-fitting of a circular tubular member 22 into bolt holes 14d respectively formed in a plurality of electromagnetic steel plates 20, the plurality of electromagnetic steel plates 20 are joined together. Further, a stator core 14 is fastened to a casing 18 by screwing a fastening bolt 16 inserted through a circular tubular member 22 into the casing 18, such that the plurality of electromagnetic steel plates 20 are coupled to each other and the stator core 14 is fixed to the casing 18.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a rotating electric machine having a cylindrical stator core centered on an axis in which a plurality of electromagnetic steel sheets are stacked in the axial direction, and relates to a technology that can suppress iron loss while maintaining the bonding force required to bond the plurality of electromagnetic steel sheets to each other. [Background technology]

[0002] There is known a rotating electric machine that includes a stator core having a cylindrical yoke portion centered on the axis and a comb tooth portion consisting of a plurality of comb teeth protruding inward at a predetermined interval from the inside of the yoke portion, the stator core being formed by stacking a plurality of electromagnetic steel sheets having insulating coatings on their surfaces in the axial direction. For example, there is a rotating electric machine described in Patent Document 1. In Patent Document 1, the plurality of electromagnetic steel sheets are fixed in a stacked state in the axial direction by forming crimping portions on each of the plurality of electromagnetic steel sheets and crimping the crimping portions to each other, or by fastening the plurality of electromagnetic steel sheets with fastening bolts. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 6-153425 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in a rotating electric machine such as that disclosed in Patent Document 1, there is a problem in that electrical conduction between the electromagnetic steel sheets occurs near the crimped portions formed to fix the multiple electromagnetic steel sheets, which generates eddy currents and increases iron loss. In response to this problem, it is conceivable to fasten the multiple electromagnetic steel sheets only with fastening bolts that penetrate the multiple electromagnetic steel sheets without using crimping, but with only fastening bolts, the bonding force that bonds the multiple electromagnetic steel sheets together becomes weak, and it becomes impossible to maintain the bonding force required to bond the multiple electromagnetic steel sheets together.

[0005] The present invention has been made against the background of the above circumstances, and its object is to provide a rotating electric machine that can suppress iron loss while maintaining the bonding force that bonds multiple electromagnetic steel sheets together. [Means for solving the problem]

[0006] The gist of a first invention is a rotating electric machine including: (a) a stator core having a cylindrical yoke portion centered on an axis and a plurality of comb teeth protruding inward at predetermined circumferential intervals from the inside of the yoke portion, the stator core being formed by stacking a plurality of electromagnetic steel sheets having insulating coatings formed on their surfaces in the axial direction; (b) fitting holes penetrating each of the plurality of electromagnetic steel sheets are formed in the plurality of electromagnetic steel sheets; and (c) a longitudinal press-in member having an insulating coating formed on its surface is press-fitted into the fitting holes to fix the plurality of electromagnetic steel sheets to each other. (d) the longitudinal press-in member is a flat plate formed integrally with at least one of the plurality of electromagnetic steel plates and bent parallel to the axis from the at least one electromagnetic steel plate, and the fitting hole is a rectangular fitting hole into which the flat longitudinal press-in member can be press-fitted. The point is that.

[0009] No. 2 The gist of the invention is as follows: 1 In the invention, the multiple electromagnetic steel plates have bolt holes for inserting fastening bolts and rectangular fitting holes for pressing in the flat, longitudinal press-in members, and are provided with an outer peripheral convex portion protruding toward the outer periphery, and the flat, longitudinal press-in member is formed by extending radially outward from the outer peripheral convex portion of at least one of the electromagnetic steel plates and bending it parallel to the axis from the outer peripheral convex portion.

[0010] No. 3 The gist of the invention is as follows: 1 In the invention, the multiple electromagnetic steel plates have bolt holes for inserting fastening bolts and rectangular fitting holes for pressing in the flat, longitudinal press-in members, and are provided with an outer peripheral convex portion protruding toward the outer periphery, and the flat, longitudinal press-in member is formed by extending in a tangential direction from the outer peripheral convex portion of the at least one electromagnetic steel plate and bending it parallel to the axis from the outer peripheral convex portion. Effect of the Invention

[0011] According to the rotating electric machine of the first invention, the plurality of electromagnetic steel sheets are formed with fitting holes penetrating the plurality of electromagnetic steel sheets, and the plurality of electromagnetic steel sheets are fixed to one another by pressing a longitudinal press-in member having an insulating coating formed on its surface into the fitting hole. In this way, the plurality of electromagnetic steel sheets are fixed to one another without using crimping, so that it is possible to suppress iron loss while maintaining the bonding force bonding the plurality of electromagnetic steel sheets to one another. The longitudinal press-in member is a flat plate formed integrally with at least one of the plurality of electromagnetic steel sheets and bent parallel to the axis from the at least one electromagnetic steel sheet, and the fitting hole is a rectangular fitting hole into which the flat longitudinal press-in member can be press-fitted. For this reason, the press-in member formed integrally with the electromagnetic steel sheet can be simultaneously manufactured by, for example, punching the steel sheet.

[0014] No. 2 According to the rotating electric machine of the invention, the plurality of electromagnetic steel sheets are formed with bolt holes for inserting fastening bolts and the rectangular fitting holes for press-fitting the flat-plate-shaped longitudinal press-in members, and have an outer peripheral convex portion protruding outward, and the flat-plate-shaped longitudinal press-in members are formed by extending radially outward from the outer peripheral convex portion of the at least one electromagnetic steel sheet and bending the outer peripheral convex portion in parallel to the axis. Thus, the press-in members formed integrally with the electromagnetic steel sheets can be simultaneously manufactured, for example, by punching the steel sheets.

[0015] No. 3According to the rotating electric machine of the invention, the plurality of electromagnetic steel sheets are formed with bolt holes for inserting fastening bolts and rectangular fitting holes for press-fitting the flat-plate-shaped longitudinal press-in members, and have outer peripheral convex portions protruding outward, and the flat-plate-shaped longitudinal press-in members are formed by extending in a tangential direction from the outer peripheral convex portion of the at least one electromagnetic steel sheet and bending the outer peripheral convex portion in a direction parallel to the axis. Thus, since the press-in members formed integrally with the electromagnetic steel sheets are extended in the tangential direction, it is possible to increase the material yield when simultaneously manufacturing the press-in members by, for example, punching the steel sheets. [Brief description of the drawings]

[0016] [Figure 1] 1 is a vertical cross-sectional view showing a main portion of a rotating electric machine for a vehicle according to the present invention; [Diagram 2] 2 is a cross-sectional view showing a main part of the vehicle rotating electric machine of FIG. 1. [Diagram 3] 3 is a cross-sectional view of the vehicle rotating electric machine taken along line III-III of FIG. 2. [Figure 4] 7 is a vertical cross-sectional view taken along line IV-IV in FIG. 6, illustrating the configuration of a stator core provided in a vehicle rotating electric machine according to another embodiment (embodiment 2) of the present invention. FIG. [Diagram 5] 5 is a cross-sectional view showing a state in which a plurality of first electromagnetic steel plates and a plurality of second electromagnetic steel plates that constitute the stator core of FIG. 4 are assembled together. [Figure 6] 6 is a view of one of the plurality of first electromagnetic steel sheets in FIG. 5, as viewed in the direction of arrow VI. [Figure 7] 7 is a view of the second electromagnetic steel sheet before the press-fit portion is bent in FIG. 5, as viewed from direction VII. [Figure 8] 13 is a cross-sectional view taken along line VIII-VIII of FIG. 10, illustrating the configuration of a stator core provided in a vehicle rotating electric machine according to another embodiment (third embodiment) of the present invention. FIG. [Figure 9] 9 is a cross-sectional view showing a state in which a plurality of first electromagnetic steel plates and a plurality of second electromagnetic steel plates that constitute the stator core of FIG. 8 are being assembled together. [Figure 10]10 is a view of one of the plurality of first electromagnetic steel sheets in FIG. 9 as viewed from the direction of arrow X. FIG. [Figure 11] 10 is a view of the second electromagnetic steel sheet in FIG. 9 before the press-fit portion is bent, as viewed from direction XI. [Figure 12] FIG. 4 is a diagram showing the relationship between the iron loss ratio of the stator cores of Examples 1, 2, and 3 and the stator core of a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that in the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios and shapes of the various parts are not necessarily drawn accurately. EXAMPLES

[0018] FIG. 1 is a vertical cross-sectional view illustrating a main part of a rotating electric machine MG for a vehicle to which the present invention is suitably applied, and FIG. 2 is a horizontal cross-sectional view illustrating a main part of the rotating electric machine MG for a vehicle. The rotating electric machine MG for a vehicle is, for example, a driving source for driving a hybrid vehicle or an electric vehicle, and is an AC synchronous motor having a function as an electric motor (motor) or a generator (generator). The rotating electric machine MG for a vehicle includes a cylindrical stator core 14 centered on an axis CL about which the rotor 10 rotates, and the rotor 10 disposed on the inner periphery side of the stator core 14 and rotatably supported by a bearing (not shown) in a casing 18. When a rotating magnetic field is generated from the stator core 14 by a stator coil (not shown) provided in the stator core 14, the rotor 10 incorporating a plurality of permanent magnets 12 is rotated at a rotation speed corresponding to the rotating magnetic field.

[0019] 1, the stator core 14 is fixed inside the casing 18, which is a non-rotating member, by screwing a plurality of fastening bolts 16 (three in this embodiment) into the casing 18. Also, FIG. 2 is a diagram for explaining the configuration of the stator core 14.

[0020] 1 and 2, the stator core 14 integrally comprises an annular or circular yoke portion 14a centered on the axis CL, a plurality of comb teeth 14b protruding inward from the inside of the yoke portion 14a at a predetermined interval t, an outer peripheral protrusion 14c protruding outward from the yoke portion 14a, and a circular bolt hole 14d formed in the outer peripheral protrusion 14c. As shown in FIG. 3, the stator core 14 is formed by stacking a plurality of electromagnetic steel sheets 20 in the direction of the axis CL, the surfaces of which are coated with a well-known insulating coating such as an organic-inorganic mixed film having a thickness of 1 to several μm.

[0021] The yoke portion 14a of the stator core 14 is formed by stacking yoke portions 20a formed on electromagnetic steel sheets 20 in the axial direction CL, the comb teeth 14b of the stator core 14 are formed by stacking comb teeth 20b formed on electromagnetic steel sheets 20 in the axial direction CL, the outer circumferential protrusion 14c of the stator core 14 is formed by stacking outer circumferential protrusions 20c formed on the electromagnetic steel sheets 20 in the axial direction CL, and the bolt holes 14d of the stator core 14 are formed by stacking bolt holes 20d formed on the electromagnetic steel sheets 20 in the axial direction CL. The multiple electromagnetic steel sheets 20 each have the same shape.

[0022] In the stator core 14 configured in this manner, a circular tubular member 22 having an insulating coating formed on its surface is press-fitted into a bolt hole 14d formed in each of the electromagnetic steel sheets 20. The circular tubular member 22 functions as a longitudinal press-fit member of the present invention, and the bolt hole 14d functions as a fitting hole into which the circular tubular member 22 is press-fitted. The circular tubular member 22 has a through hole 24 having an inner diameter that allows the screw shaft portion 16a of the fastening bolt 16 to be inserted. The circular tubular member 22 is press-fitted into the bolt hole 14d formed in each of the electromagnetic steel sheets 20, thereby joining the multiple electromagnetic steel sheets 20 to each other. In addition, the fastening bolt 16 inserted into the circular tubular member 22 is screwed into the casing 18, thereby fastening the stator core 14 to the casing 18, thereby joining the multiple electromagnetic steel sheets 20 to each other and fixing the stator core 14 to the casing 18.

[0023] Next, another embodiment of the present invention will be described. In the following description, parts common to the embodiments are given the same reference numerals and the description thereof will be omitted. EXAMPLES

[0024] 4 is a vertical cross-sectional view illustrating the configuration of a stator core 100 provided in a vehicle rotating electric machine MG according to another embodiment (embodiment 2) of this embodiment. The vehicle rotating electric machine MG of this embodiment is substantially the same as the vehicle rotating electric machine MG of embodiment 1 except that one electromagnetic steel sheet 104 out of a plurality of electromagnetic steel sheets has a different shape from the other electromagnetic steel sheets 102.

[0025] As shown in FIG. 4, the stator core 100 integrally comprises an annular, i.e., cylindrical, yoke portion 100a centered on the axis CL, a plurality of comb teeth 100b protruding inwardly at a predetermined interval t from the inside of the yoke portion 100a, an outer circumferential convex portion 100c protruding outwardly from the yoke portion 100a, a bolt hole 100d formed in the outer circumferential convex portion 100c, and a rectangular fitting hole 100e formed independently in the outer circumferential convex portion 100c outside the bolt hole 100d.

[0026] As shown in Figures 4 and 5, the stator core 100 is formed by stacking a plurality of electromagnetic steel plates in the direction of the axis CL, including a plurality of annular first electromagnetic steel plates (electromagnetic steel plates) 102 having an insulating coating formed on their surfaces and a plurality of annular second electromagnetic steel plates (electromagnetic steel plates) 104 having an insulating coating formed on their surfaces.

[0027] That is, the yoke portion 100a of the stator core 100 is formed by stacking, in the axial direction CL, yoke portions 102a (see FIG. 6 ) formed on the multiple first electromagnetic steel sheets 102 and yoke portions 104a (see FIG. 7 ) formed on the multiple second electromagnetic steel sheets 104, respectively. The comb teeth 100b of the stator core 100 are formed by stacking, in the axial direction CL, comb teeth 102b (see FIG. 6 ) formed on the multiple first electromagnetic steel sheets 102 and comb teeth 104b (see FIG. 7 ) formed on the multiple second electromagnetic steel sheets 104, respectively. The outer circumferential protrusion 100c of the stator core 100 is formed by stacking, in the axial direction CL, comb teeth 102b (see FIG. 6 ) formed on the multiple first electromagnetic steel sheets 102 and comb teeth 104b (see FIG. 7 ) formed on the multiple second electromagnetic steel sheets 104, respectively. 5 is a cross-sectional view showing a state in which a plurality of first electromagnetic steel sheets 102 and a second electromagnetic steel sheet 104 are assembled together in the axial direction CL, and a bolt hole 102d (see FIG. 6) formed in each of the first electromagnetic steel sheets 102 and a bolt hole 104d (see FIG. 7) formed in the second electromagnetic steel sheet 104 are assembled together in the axial direction CL, and a rectangular fitting hole 100e of the stator core 100 is formed by stacking a rectangular fitting hole 102e (see FIG. 6) formed in each of the first electromagnetic steel sheets 102 and a bolt hole 104d (see FIG. 7) formed in the second electromagnetic steel sheet 104 in the axial direction CL. FIG. 5 is a cross-sectional view showing a state in which a plurality of first electromagnetic steel sheets 102 and a second electromagnetic steel sheet 104 constituting the stator core 100 in FIG. 4 are assembled together.

[0028] Fig. 6 is a view of one of the multiple first electromagnetic steel sheets 102 in Fig. 5, as viewed in the direction of arrow VI. Fig. 7 is a view of the second electromagnetic steel sheet 104, as viewed in the direction of arrow VII, before a press-fit portion 104e, which will be described later, is bent in Fig. 5. The bolt hole 100d of the stator core 100 is a hole through which the screw shaft portion 16a of the fastening bolt 16 for fastening the stator core 100 to the casing 18 is inserted.

[0029] As shown in Fig. 6, each of the first electromagnetic steel sheets 102 integrally includes an annular or circular yoke portion 102a centered on the axis CL, a plurality of comb teeth 102b protruding inward from the inside of the yoke portion 102a at a predetermined interval t, three outer peripheral protrusions 102c protruding outward from the yoke portion 102a of the annular first electromagnetic steel sheet 102, a circular bolt hole 102d formed in each of the three outer peripheral protrusions 102c, and a rectangular fitting hole 102e independently formed outside the bolt hole 102d at the tip of each of the three outer peripheral protrusions 102c. The rectangular fitting hole 102e, i.e., the rectangular fitting hole 100e, is disposed outside the bolt hole 102d in the radial direction of the first electromagnetic steel sheet 102 at the tip of the outer peripheral protrusion 102c. The first electromagnetic steel sheet 102 is manufactured, for example, by punching a flat steel sheet by a press. Moreover, the multiple first electromagnetic steel sheets 102 are each formed into the same shape.

[0030] As shown in Fig. 7, one electromagnetic steel sheet 104 among the plurality of electromagnetic steel sheets constituting the stator core 100 integrally includes an annular or circular yoke portion 104a centered on the axis CL, a plurality of comb teeth 104b protruding inward from the inside of the yoke portion 104a at a predetermined interval t, three outer peripheral protrusions 104c protruding outward from the yoke portion 104a of the annular second electromagnetic steel sheet 104, circular bolt holes 104d formed in each of the three outer peripheral protrusions 104c, and longitudinal plate-shaped press-in portions (longitudinal press-in members) 104e formed at the tip portions of the three outer peripheral protrusions 104c. When viewed from the axis CL direction, the second electromagnetic steel sheet 104 has the same shape as the first electromagnetic steel sheet 102, except that the shapes of the tip portions of the three outer peripheral protrusions 104c are different, as shown in Figs. 6 and 7. That is, the shapes of the yoke portion 104a, the comb teeth 104b, and the bolt holes 104d of the second electromagnetic steel sheet 104 are the same as those of the yoke portion 102a, the comb teeth 102b, and the bolt holes 102d of the first electromagnetic steel sheet 102. The press-fit portion 104e of the second electromagnetic steel sheet 104 is a portion extending in the radial direction of the second electromagnetic steel sheet 104 from the tip portions of three outer peripheral protrusions 104c formed on the second electromagnetic steel sheet 104 as shown in FIG. 7, and the second electromagnetic steel sheet 104 is manufactured, for example, by punching out a flat steel sheet by a press and bending the portions extending in the radial direction of the second electromagnetic steel sheet 104 from the tip portions of the three outer peripheral protrusions 104c so as to be parallel to the axis CL direction as shown in FIG. 5. The dashed line shown in FIG. 5 indicates the press-fit portion 104e before being bent.

[0031] In the stator core 100, as shown in Fig. 5, the press-fit portion 104e integrally formed in the second electromagnetic steel sheet 104 is press-fitted into the rectangular fitting holes 102e formed in each of the first electromagnetic steel sheets 102, i.e., the rectangular fitting holes 100e formed in the stator core 100, so that the first electromagnetic steel sheets 102 and the second electromagnetic steel sheets 104 are integrally assembled in a state in which they are stacked in the axis CL direction as shown in Fig. 4. The press-fit portion 104e of the second electromagnetic steel sheet 104 functions as a longitudinal press-fit member press-fitted into the rectangular fitting holes 102e of the first electromagnetic steel sheets 102, i.e., the rectangular fitting holes 100e of the stator core 100. The rectangular fitting holes 100e of the stator core 100 are formed to be slightly smaller than the press-fit portion 104e of the second electromagnetic steel sheet 104.

[0032] In the stator core 100 configured in this manner, the multiple first electromagnetic steel sheets 102 and the second electromagnetic steel sheets 104 are joined to each other by pressing the press-fit portions 104e of the second electromagnetic steel sheets 104 into the rectangular mating holes 102e formed in each of the multiple first electromagnetic steel sheets 102, and the multiple first electromagnetic steel sheets 102 and the second electromagnetic steel sheets 104 are joined to each other by fastening the stator core 100 to the casing 18 with fastening bolts 16 inserted into the bolt holes 100d.

[0033] As described above, according to the vehicle rotating electric machine MG of this embodiment, one of the plurality of electromagnetic steel sheets 102, 104, the second electromagnetic steel sheet 104, is integrally formed with a press-fit portion 104e to be press-fitted into a rectangular fitting hole 100e formed in the stator core 100. Therefore, the plurality of electromagnetic steel sheets 102, 104 can be fixed by press-fitting the press-fit portion 104e into the rectangular fitting hole 100e formed in the stator core 100. As a result, the plurality of electromagnetic steel sheets 102, 104 can be bonded to each other by press-fitting the press-fit portion 104e without using crimping, so that iron loss can be suppressed while maintaining the bonding force bonding the plurality of electromagnetic steel sheets 102, 104 to each other.

[0034] Furthermore, according to the vehicle rotating electric machine MG of this embodiment, the multiple electromagnetic steel sheets 102, 104 are formed with outer peripheral convex portions 102c, 104c that protrude outward from the annular electromagnetic steel sheets 102, 104, respectively, and the press-fit portion 104e is formed by bending a portion that extends in the radial direction of the second electromagnetic steel sheet 104 from the tip of the outer peripheral convex portion 104c so as to be parallel to the direction of the axis CL. For this reason, the second electromagnetic steel sheet 104 with the press-fit portion 104e integrally formed therewith can be suitably manufactured by, for example, punching a steel sheet.

[0035] Furthermore, according to the vehicle rotating electric machine MG of this embodiment, the outer circumferential protrusions 102c, 104c are formed with bolt holes 102d, 104d through which fastening bolts 16 for fastening the stator core 100 to the casing 18 are inserted, and the rectangular fitting hole 100e is formed independently outside the bolt holes 102d, 104d in the outer circumferential protrusions 102c, 104c. Therefore, the press-fit portions 104e and the fastening bolts 16 can appropriately fix the multiple electromagnetic steel sheets 102, 104, respectively. EXAMPLES

[0036] 8 is a cross-sectional view for explaining the configuration of a stator core 200 provided in a vehicle rotating electric machine of another embodiment (embodiment 3) of this embodiment. The vehicle rotating electric machine of this embodiment differs in that the shape of the rectangular fitting hole 102f of the first electromagnetic steel sheet 102 is different, i.e., the shape of the rectangular fitting hole 100f of the stator core 200 is elongated in the radial direction, and the shape of the tip of the outer circumferential protrusion 104c of the second electromagnetic steel sheet 104 is different in the stator core 200. The rest is substantially the same as the vehicle rotating electric machine of embodiment 2.

[0037] As shown in Fig. 8, the stator core 200 integrally includes a yoke portion 100a, comb teeth 100b, an outer circumferential protrusion 100c, a bolt hole 100d, and a rectangular fitting hole 100f formed independently outside the bolt hole 100d in the outer circumferential protrusion 100c. As shown in Figs. 8 and 9, the stator core 200 is formed by stacking a plurality of electromagnetic steel sheets including a plurality of first electromagnetic steel sheets 102 and a plurality of second electromagnetic steel sheets 104 in the axial direction CL, and the rectangular fitting hole 100f of the stator core 200 is formed by stacking rectangular fitting holes 102f (see Fig. 10) described later formed in the plurality of first electromagnetic steel sheets 102 in the axial direction CL. Fig. 9 is a cross-sectional view showing a state in which the plurality of first electromagnetic steel sheets 102 and the second electromagnetic steel sheets 104 constituting the stator core 200 in Fig. 8 are assembled. Fig. 10 is a view of one of the multiple first electromagnetic steel sheets 102 in Fig. 9, as viewed from the direction of arrow X. Fig. 11 is a view of the second electromagnetic steel sheet 104, as viewed from the direction of arrow XI, before a press-fit portion 104f, which will be described later, in Fig. 9 is bent.

[0038] 10, each of the first electromagnetic steel sheets 102 integrally includes a yoke portion 102a, multiple comb teeth 102b, three outer circumferential protrusions 102c, a bolt hole 102d, and a rectangular fitting hole 102f formed independently outside the bolt hole 102d at the tip of each of the three outer circumferential protrusions 102c. Note that the rectangular fitting hole 102f, i.e., the rectangular fitting hole 100f, is disposed radially outward of the first electromagnetic steel sheet 102 with respect to the bolt hole 102d at the tip of the outer circumferential protrusion 102c.

[0039] The second electromagnetic steel sheet 104, i.e., one of the multiple electromagnetic steel sheets that make up the stator core 200, integrally has a yoke portion 104a, a multiple comb teeth 104b, three outer peripheral protrusions 104c, a bolt hole 104d, and a longitudinal plate-shaped press-in portion (longitudinal press-in member) 104f extending tangentially from the tip ends of the three outer peripheral protrusions 104c, as shown in FIG. 11. The press-fit portions 104f of the second electromagnetic steel sheet 104 are portions extending in the tangential direction of the second electromagnetic steel sheet 104 from the tip ends of the three outer peripheral convex portions 104c formed on the second electromagnetic steel sheet 104, as shown in FIG. 11. The second electromagnetic steel sheet 104 is manufactured, for example, by punching out a flat steel sheet using a press, and bending the portions extending in the tangential direction of the second electromagnetic steel sheet 104 from the tip ends of the three outer peripheral convex portions 104c so that they are parallel to the axis CL direction, as shown in FIGS. 8 and 9.

[0040] In the stator core 200, as shown in Fig. 9, the press-fit portion 104f integrally formed in the second electromagnetic steel sheet 104 is press-fitted into the rectangular fitting holes 102f formed in each of the first electromagnetic steel sheets 102, i.e., the rectangular fitting holes 100f formed in the stator core 200, so that the first electromagnetic steel sheets 102 and the second electromagnetic steel sheets 104 are integrally assembled in a state in which they are stacked in the axis CL direction as shown in Fig. 8. The press-fit portion 104f of the second electromagnetic steel sheet 104 functions as a longitudinal press-fit member press-fitted into each of the rectangular fitting holes 102f of the first electromagnetic steel sheets 102, i.e., the rectangular fitting holes 100f of the stator core 200. The rectangular fitting holes 100f of the stator core 200 are formed to be slightly smaller than the press-fit portion 104f of the second electromagnetic steel sheet 104.

[0041] As described above, according to the vehicle rotating electric machine MG of this embodiment, the multiple electromagnetic steel sheets 102, 104 are formed with the outer peripheral convex parts 102c, 104c that protrude outward from the annular electromagnetic steel sheets 102, 104, respectively, and the press-fit part 104f is formed by bending a part that extends from the tip part of the outer peripheral convex part 104c in the tangential direction of the second electromagnetic steel sheet 104 so as to be parallel to the axis CL direction. Therefore, the second electromagnetic steel sheet 104 integrally formed with the press-fit part 104f can be suitably manufactured by, for example, punching a steel sheet, and the amount of sheet material remaining when the steel sheet is punched can be suitably reduced.

[0042] FIG. 12 is a diagram showing the relative ratio of the iron loss when the stator core 14 of Example 1, the stator core 100 of Example 2, and the stator core 200 of Example 3 are used, which are measured at 400 Hz and with an amplitude value of the magnetic flux density of the yoke portion of 1.25 T, respectively, and the measured iron loss of the stator core of the comparative example is set to 1. The stator core of the comparative example is different from the stator core 14 of Example 1 in that a longitudinal press-in member is not provided, and the plurality of electromagnetic steel sheets 20 are joined by forming a crimping portion on each of the plurality of electromagnetic steel sheets 20 and crimping the crimping portion as in Patent Document 1, for example, and is otherwise substantially the same as the stator core 14 of Example 1. As shown in FIG. 12, the iron loss ratio of the stator core 14 of Example 1, the stator core 100 of Example 2, and the stator core 200 of Example 3 to the comparative example was 17% or more lower. That is, in the stator cores 14, 100, 200, the multiple electromagnetic steel sheets 20 are joined to each other by pressing the cylindrical member 22 and the press-in portions (longitudinal press-in members) 104e, 104f into the bolt holes 14d, which function as fitting holes, and the rectangular fitting holes 100e, 100f, without using crimping, so that iron loss can be suppressed by the amount of iron loss that occurs when crimping is used (crimping iron loss).

[0043] Although the embodiment of the present invention has been described in detail above with reference to the drawings, the present invention can be applied to other embodiments.

[0044] For example, in the above-mentioned second embodiment, the stator core 100 is composed of a plurality of electromagnetic steel sheets 102 and 104, i.e., a plurality of first electromagnetic steel sheets 102 and a plurality of second electromagnetic steel sheets 104, and one of the plurality of electromagnetic steel sheets 102 and 104, i.e., the second electromagnetic steel sheet 104, is integrally formed with a press-fit portion 104e to be press-fitted into a rectangular fitting hole 100e formed in the stator core 100. For example, a fitting hole other than the rectangular fitting hole 100e may be provided in the stator core 100, and a press-fit portion to be press-fitted into a fitting hole other than the rectangular fitting hole 100e may be integrally formed in one of the plurality of first electromagnetic steel sheets 102. In other words, in the stator core 100, a press-fit portion to be press-fitted into a hole portion formed in the stator core 100 may be integrally formed in at least one of the plurality of electromagnetic steel sheets 102 and 104.

[0045] In the stator core 100 in the second embodiment described above, the press-fit portions 104e integrally formed with the second electromagnetic steel sheet 104 are press-fitted into the rectangular fitting holes 102e formed in each of the first electromagnetic steel sheets 102. For example, the press-fit portions 104e of the second electromagnetic steel sheet 104 may be press-fitted into the rectangular fitting holes 102e of the first electromagnetic steel sheets 102 by shrink fitting, in which the press-fit portions 104e of the second electromagnetic steel sheet 104 are fitted into the rectangular fitting holes 102e of the first electromagnetic steel sheets 102 that have been heated and expanded. In addition, for example, the press-in portions 104e of the second electromagnetic steel sheet 104 may be pressed into the rectangular mating holes 102e of the multiple first electromagnetic steel sheets 102 by cold fitting, in which the press-in portions 104e of the second electromagnetic steel sheet 104, which has been cooled and reduced in size, are fitted into the rectangular mating holes 102e of the multiple first electromagnetic steel sheets 102.

[0046] Furthermore, in the above-described embodiment, the rotating electric machine MG is for use in a vehicle, but it may also be used in mobility other than a vehicle, such as an air vehicle or a ship.

[0047] It should be noted that the above is merely one embodiment, and the present invention can be embodied in various modified and improved forms based on the knowledge of those skilled in the art. [Explanation of symbols]

[0048] 14: Stator core 14a: York section 14b: Comb teeth 14c: Outer periphery protrusion 14d: Bolt hole (fitting hole) 16: Fastening bolt 18: Casing 20:Electromagnetic steel plate 20a: York section 20b: Comb teeth 20c: Outer periphery protrusion 20d: Bolt hole 22: Circular tubular member (longitudinal press-fit member) 24:Through hole 100: Stator core 100a: Yoke section 100b: Comb teeth 100c: outer periphery protrusion 100d: Bolt hole 100e: Rectangular mating hole 100f: Rectangular fitting hole 102: No. 1 electromagnetic steel plate (electromagnetic steel plate) 102a: York section 102b: Comb teeth 102c: Outer periphery protrusion 102d: Bolt hole 102e: Rectangular fitting hole 102f: Rectangular fitting hole 104:Second electromagnetic steel plate (electromagnetic steel plate) 104a: York section 104c: Outer periphery protrusion 104d: Bolt hole 104e: Press-fit portion (longitudinal press-fit member) 104f: Press-fit portion (longitudinal press-fit member) 200: Stator core CL: Axis line MG: Vehicle rotating motor t:Spacing

Claims

1. A rotating electric machine for a vehicle, comprising a stator core having a cylindrical yoke portion centered on an axis and a plurality of comb teeth protruding inwardly at predetermined circumferential intervals from an inside of the yoke portion, the stator core being formed by stacking a plurality of electromagnetic steel plates having insulating coatings formed on their surfaces in the axial direction, The plurality of electromagnetic steel sheets each have a fitting hole formed therethrough, a longitudinal press-in member having an insulating coating formed on its surface is press-fitted into the fitting hole, thereby fixing the plurality of electromagnetic steel sheets to each other; The longitudinal press-in member is a flat plate formed integrally with at least one of the plurality of electromagnetic steel plates and bent parallel to the axis from the at least one electromagnetic steel plate, and the fitting hole is a rectangular fitting hole into which the flat longitudinal press-in member can be press-fitted. A rotating electric machine for a vehicle.

2. The plurality of electromagnetic steel plates are formed with bolt holes for inserting fastening bolts and rectangular fitting holes for press-fitting the flat-plate-shaped longitudinal press-in members, and have outer peripheral protrusions protruding outward, and the flat-plate-shaped longitudinal press-in members are formed by extending radially outward from the outer peripheral protrusions of the at least one electromagnetic steel plate and bending the outer peripheral protrusions in a direction parallel to the axis.

2. The rotating electric machine for a vehicle according to claim 1.

3. The plurality of electromagnetic steel sheets are formed with bolt holes for inserting fastening bolts and rectangular fitting holes for press-fitting the flat-plate-shaped longitudinal press-in members, and have outer peripheral protrusions protruding toward the outer periphery, and the flat-plate-shaped longitudinal press-in members are formed by extending in a tangential direction from the outer peripheral protrusions of the at least one electromagnetic steel sheet and bending the outer peripheral protrusions in a direction parallel to the axis.

2. The rotating electric machine for a vehicle according to claim 1.

Images