Rotating electric machine

Abstract

This rotating electric machine includes: a rotor having a shaft; a stator surrounding the rotor; a bearing supporting the shaft so as to be rotatable about a central axis; and a housing. The housing has a bearing bracket for supporting the bearing, and houses the rotor and the stator. The bearing bracket includes a wall and a reinforcement part. The wall has: an inner peripheral part which forms a first hole into which the bearing is inserted and supports the bearing; and an outer peripheral part. The wall is provided with a second hole which is positioned radially outward of the first hole with respect to the central axis, extends through the wall in the axial direction of the central axis, and extends in a direction intersecting the axial direction. The reinforcement part is provided on the wall, has a first end portion on the outer side in the radial direction and a second end portion on the inner side in the radial direction, and extends in a direction intersecting the radial direction of the central axis and protrudes in the axial direction of the central axis. The second end portion is positioned on the second hole side with respect to a straight line connecting the first end portion and the central axis.

Description

Rotating electrical machine

[0001] An embodiment of the present invention relates to a rotating electrical machine.

[0002] Conventionally, there is a rotating electrical machine in which a reinforcing portion is attached to a bearing bracket that supports a bearing. For this type of rotating electrical machine, for example, there is a configuration in which a bearing bracket is provided with a hole into which a shaft of a rotor is inserted and a hole for measuring a gap between a stator and a rotor.

[0003] Japanese Patent No. 7060673

[0004] However, for a bearing bracket provided with holes other than the hole into which the shaft is inserted as described above, there is room for improvement in the structure in order to improve the load-bearing capacity of the bearing bracket.

[0005] An example of a problem to be solved by the present invention is to obtain a rotating electrical machine capable of improving the load-bearing capacity of a bearing bracket provided with holes other than the hole into which a shaft is inserted.

[0006] A rotating electrical machine according to an embodiment of the present invention includes a rotor having a shaft, a stator surrounding the rotor, a bearing that supports the shaft rotatably about a central axis, and a housing. The housing has a bearing bracket that supports the bearing and houses the rotor and the stator. The bearing bracket includes a wall and a reinforcing portion. The wall has an inner peripheral portion that forms a first hole into which the bearing is inserted and supports the bearing, and an outer peripheral portion, and a second hole is provided on the radially outer side of the central axis with respect to the first hole and penetrates in the axial direction of the central axis, and extends in a direction intersecting the axial direction. The reinforcing portion is provided on the wall, has a first end portion on the radially outer side and a second end portion on the radially inner side, extends in a direction intersecting the radial direction of the central axis and protrudes in the axial direction of the central axis, and the second end portion is located on the second hole side with respect to a straight line connecting the first end portion and the central axis.

[0007] According to the present invention, it is possible to obtain a rotating electrical machine capable of improving the load-bearing capacity of a bearing bracket provided with holes (second holes) other than the hole (first hole) into which the shaft is inserted.

[0008] Figure 1 is a schematic cross-sectional view showing a rotating electric machine according to an embodiment. Figure 2 is a rear view showing a bearing bracket according to an embodiment. Figure 3 is a side view showing a bearing bracket according to an embodiment. Figure 4 is a diagram showing the analysis results of a bearing bracket according to a comparative example.

[0009] Illustrative embodiments of the present invention are disclosed below. The configurations of the embodiments shown below, as well as the functions and effects brought about by such configurations, are examples only. The present invention can also be realized by configurations other than those disclosed in the following embodiments. Furthermore, according to the present invention, it is possible to obtain at least one of the various effects (including derived effects) that can be obtained by the configuration.

[0010] Furthermore, the drawings are schematic, and the dimensional relationships and proportions of each element may differ from reality. Also, there may be differences in dimensional relationships and proportions between drawings. In this specification, ordinal numbers are used solely to distinguish parts, components, locations, directions, etc., and do not indicate order or priority.

[0011] As shown in each drawing, the X-axis, Y-axis, and Z-axis are defined herein for convenience. The X-axis, Y-axis, and Z-axis are orthogonal to each other. The X-axis is along the axial direction of the central axis A of the shaft 30, which will be described later. The Y-axis is perpendicular to the central axis A. The Z-axis is perpendicular to the central axis A and the horizontal direction.

[0012] Furthermore, the X, Y, and Z directions are defined herein. The X direction is the direction along the X axis and includes the +X direction indicated by the X-axis arrow and the -X direction which is the opposite direction of the X-axis arrow. That is, one axial direction of the central axis A of the shaft 30 is the +X direction, and the other axial direction of the central axis A is the -X direction. The Y direction is the direction along the Y axis and includes the +Y direction indicated by the Y-axis arrow and the -Y direction which is the opposite direction of the Y-axis arrow. The Z direction is the direction along the Z axis and includes the +Z direction indicated by the Z-axis arrow and the -Z direction which is the opposite direction of the Z-axis arrow. In this embodiment, the +Z direction coincides with the vertical upward direction.

[0013] Figure 1 is a schematic cross-sectional view showing a rotating electric machine 1 according to an embodiment. As shown in Figure 1, the rotating electric machine 1 is, for example, a synchronous motor. Note that the rotating electric machine 1 is not limited to this example.

[0014] The rotating electric machine 1 comprises a stator 2, a rotor 3, a housing 4, and two bearings 6.

[0015] The rotor 3 comprises a shaft 30, a rotor core 31, and rotor windings 32. The rotor core 31 protrudes from the outer circumference of the shaft 30 and is located inside the stator core 21. The rotor windings 32 are rectangular in shape and are inserted into the rotor core 31. The shaft 30 is rotatable around a central axis A. In other words, the rotor 3 is rotatable around a central axis A.

[0016] The axial, radial, and circumferential directions of the central axis A are the same as the axial, radial, and circumferential directions of the shaft 30. In the following description, unless otherwise specified, the axial, radial, and circumferential directions refer to the axial, radial, and circumferential directions of the central axis A, i.e., the axial, radial, and circumferential directions of the shaft 30.

[0017] The stator 2 comprises a stator core 21 and stator windings 22. The stator core 21 is formed in a substantially cylindrical shape surrounding a central axis A and the rotor 3. The central axis A is the center of rotation of the rotor 3 and the shaft 30 in the rotating electric machine 1. The central axis A is, for example, a hypothetical straight line passing through the center of the shaft 30. The stator windings 22 are attached to the stator core 21 by passing through slots provided in the stator core 21.

[0018] The housing 4 has a frame 41 and two bearing brackets 42. The frame 41 is formed in a substantially cylindrical shape surrounding the central axis A. The stator 2 and rotor 3 are arranged inside the frame 41. The stator core 21 is fixed to the frame 41.

[0019] The two bearing brackets 42 are connected to both ends of the frame 41 in the axial direction. The bearing brackets 42 fill the space inside the frame 41. The bearing brackets 42 are formed in a substantially disc shape and have an opening 420 in the center through which the shaft 30 and bearing 6 pass. The opening 420 is an example of a first hole. Each of the bearing brackets 42 supports the corresponding bearing 6. The bearing brackets 42 are located on the +X side and the opposite side of the housing 4.

[0020] The bearing bracket 42 on the +X side has a semicircular upper bracket 43 located above the shaft 30 and a semicircular lower bracket 44 located below the shaft 30. The bearing bracket 42 on the -X side has a semicircular upper bracket 45 located above the shaft 30 and a semicircular lower bracket 46 located below the shaft 30. In other words, the bearing bracket 42 on the +X side is composed of a combination of two upper and lower members (upper bracket 43 and lower bracket 44). The bearing bracket 42 on the -X side is composed of a combination of two upper and lower members (upper bracket 45 and lower bracket 46). Note that the bearing bracket 42 may also be composed of a single member.

[0021] The shaft 30 is formed in a substantially cylindrical shape extending along the central axis A. The shaft 30 has an end face 30a in the axial direction +X, an end face 30b in the opposite direction, and an outer circumferential surface 30c. The outer circumferential surface 30c extends across the two end faces 30a and 30b. The shaft 30 passes between the bearing brackets 42 and extends both inside and outside the housing 4. The shaft 30 is supported by bearings 6 so as to be rotatable around the central axis A.

[0022] The shaft 30 extends axially through the inside of the stator 2 and the rotor core 31. The shaft 30 is coupled (fixed) to the rotor core 31 of the rotor 3. The rotor 3 and the shaft 30 can rotate together as a unit around the central axis A relative to the stator 2.

[0023] The two bearings 6 are positioned on the opposite side of the rotor 3 from the axial +X direction. That is, the rotor 3 is located between the two bearings 6. The two bearings 6 support the shaft 30 so that it can rotate around the central axis A.

[0024] Figure 2 is a rear view showing the bearing bracket 42 according to the embodiment. That is, Figure 2 is a diagram showing the bearing bracket 42 from an axial line of sight. In this embodiment, the case of the bearing bracket 42 on the +X side will be described as an example. Note that the bearing bracket 42 on the -X side may have a similar configuration. The front of the bearing bracket 42 is the surface showing the bearing bracket 42 from the +X direction. The rear of the bearing bracket 42 is the surface opposite to the front. The bearing bracket 42 comprises the wall 430 of the upper bracket 43 and the wall 440 of the lower bracket 44, which extend in a direction intersecting the axial direction.

[0025] Furthermore, the vertical lines extending from the upper bracket 43 and the lower bracket 44 are defined as vertical lines C1, and the lines intersecting vertical lines C1 horizontally are defined as horizontal lines C2.

[0026] As shown in Figure 2, the upper bracket 43 is provided with an outer circumferential fastening hole 431, an inner circumferential fastening hole 432, and a measurement hole 433. The upper bracket 43 also comprises a wall 430, a reinforcing portion 7, a connecting portion 74, and an inner reinforcing portion 75.

[0027] Multiple outer perimeter fastening holes 431 are provided along the outer perimeter 437 of the upper bracket 43. One example of an outer perimeter fastening hole 431 is a hole for fastening the frame 41 and the upper bracket 43. For example, there are 10 outer perimeter fastening holes 431. The frame 41 and the upper bracket 43 are fastened (fixed) together by fasteners such as bolts inserted into the outer perimeter fastening holes 431.

[0028] Multiple inner circumferential fastening holes 432 are provided along the inner circumferential portion 438 of the upper bracket 43. One example of an inner circumferential fastening hole 432 is a hole for fastening the bearing 6 to the upper bracket 43. For example, there are seven inner circumferential fastening holes 432. The bearing 6 and the upper bracket 43 are fastened (fixed) together by fasteners such as bolts inserted into the inner circumferential fastening holes 432.

[0029] Multiple measurement holes 433 are provided. These multiple measurement holes 433 include a first measurement hole 434, a second measurement hole 435, and a third measurement hole 436. The measurement holes 433 penetrate the upper bracket 43 in the axial direction. The measurement holes 433 are aligned in the axial direction with the gap between the stator 2 and the rotor 3, specifically the gap between the stator core 21 and the rotor core 31. An instrument (measuring device) for measuring the gap between the stator 2 and the rotor 3 is inserted into the measurement holes 433.

[0030] The first measuring hole 434 is located in the center of the upper bracket 43 in the Y direction. The first measuring hole 434 is located radially outside the opening 420. The first measuring hole 434 is an example of a second hole. The second measuring hole 435 is located in the +Y direction from the first measuring hole 434 and in the -Z direction from the first measuring hole 434. The third measuring hole 436 is located in the -Y direction from the first measuring hole 434 and in the -Z direction from the first measuring hole 434. The third measuring hole 436 is located at the same height as the second measuring hole 435 in the Z direction.

[0031] The wall 430 has an inner circumferential portion 438 that forms an opening 420 into which the bearing 6 is inserted and supports the bearing 6, and an outer circumferential portion 437. The wall 430 is located radially outward from the central axis A relative to the opening 420 and has a first measuring hole 434 that penetrates in the axial direction of the central axis A and extends in a direction intersecting the axial direction.

[0032] Multiple reinforcing parts 7 are provided. The multiple reinforcing parts 7 include a pair of first reinforcing parts 71, a pair of second reinforcing parts 72, and a pair of third reinforcing parts 73.

[0033] The reinforcing portion 7 protrudes axially from the back surface of the wall 430 of the upper bracket 43. The reinforcing portion 7 extends in a direction intersecting the radial direction of the central axis A. The reinforcing portion 7 is one example of a plate-shaped rib. The reinforcing portion 7 is fixed to the upper bracket 43. The reinforcing portion 7 may also be a protrusion (bead) that is a part of the wall 430 that protrudes axially. The reinforcing portion 7 may also be provided on the front surface of the upper bracket 43.

[0034] Each pair of first reinforcing portions 71 has a radially outer first end 711 and a radially inner second end 712. The pair of first reinforcing portions 71 extend from the outer circumference 437 to the inner circumference 438. The pair of first reinforcing portions 71 are located on both sides of the first measuring hole 434 in the circumferential direction (or Y direction). In other words, the first measuring hole 434 is located between the pair of first reinforcing portions 71 in the circumferential direction. The second end 712 is located on the first measuring hole 434 side with respect to the straight line a1 connecting the first end 711 and the central axis A.

[0035] Each pair of second reinforcing portions 72 has a radially outer first end 721 and a radially inner second end 722. The pair of second reinforcing portions 72 extend from the outer circumference 437 to the inner circumference 438. The pair of second reinforcing portions 72 are located on both sides of the pair of first reinforcing portions 71 in the circumferential direction (or Y direction). In other words, the pair of first reinforcing portions 71 are located between the pair of second reinforcing portions 72 in the circumferential direction. The second end 722 is located on the first measuring hole 434 side with respect to the straight line a2 connecting the first end 721 and the central axis A.

[0036] Each pair of third reinforcing portions 73 has a radially outer first end 731 and a radially inner second end 732. The pair of third reinforcing portions 73 extend from the outer circumference 437 to the inner circumference 438. The pair of third reinforcing portions 73 are located circumferentially (or in the Y direction) outward relative to the pair of second reinforcing portions 72. In other words, the pair of second reinforcing portions 72 are located between the pair of third reinforcing portions 73 in the circumferential direction. The second end 732 is located on the first measuring hole 434 side with respect to the straight line a3 connecting the first end 731 and the central axis A.

[0037] The pair of third reinforcing portions 73 have their second end 732 positioned in the +Z direction (upward) from the first end 731. The pair of third reinforcing portions 73 each extend along the top of the second measuring hole 435 and the third measuring hole 436.

[0038] The pair of third reinforcing portions 73 extend, for example, along the upper part of the second measuring hole 435 and the third measuring hole 436, thereby providing reinforcement in the upper part where the stress between the second measuring hole 435 and the third measuring hole 436 is high.

[0039] The connecting portion 74 protrudes axially from the back surface of the wall 430 of the upper bracket 43, extends in the Y direction between the pair of first reinforcing portions 71, and connects the pair of first reinforcing portions 71. The connecting portion 74 is located radially outward (+Z direction) of the upper bracket 43 from the first measuring hole 434. The connecting portion 74 is, for example, a plate-shaped rib and is fixed to the back surface of the wall 430.

[0040] The inner reinforcing portion 75 protrudes axially from the back surface of the wall 430 of the upper bracket 43. It extends along the periphery of the opening 420. For example, the inner reinforcing portion 75 extends along the inner circumference 438 of the upper bracket 43 from the first lower end 751 on the +Y side to the second lower end 752 on the -Y side. The inner reinforcing portion 75 is located radially inward from the reinforcing portion 7. Furthermore, the inner reinforcing portion 75 is located radially inward from the plurality of measuring holes 433. That is, the inner reinforcing portion 75 is located radially inward from the first measuring hole 434. The inner reinforcing portion 75 is, for example, a plate-shaped rib and is fixed to the back surface of the wall 430.

[0041] The lower bracket 44 is provided with a lower outer circumferential fastening hole 441 and a lower inner circumferential fastening hole 442. The lower bracket 44 also comprises a wall 440, a vertical reinforcing portion 81, and a pair of outer reinforcing portions 82.

[0042] The wall 440 has an inner circumferential portion 444 that forms an opening 420 into which the bearing 6 is inserted and supports the bearing 6, and an outer circumferential portion 443. The wall 440 extends in a direction intersecting the axial direction.

[0043] Multiple lower outer perimeter fastening holes 441 are provided along the outer perimeter 443 of the lower bracket 44. One example of a lower outer perimeter fastening hole 441 is a hole used to fasten the frame 41 to the lower bracket 44. For example, there are 10 lower outer perimeter fastening holes 441. The frame 41 and the lower bracket 44 are fastened (fixed) together by fasteners such as bolts inserted into the lower outer perimeter fastening holes 441.

[0044] The lower inner peripheral fastening holes 442 are provided in plurality along the inner peripheral portion 444 of the lower bracket 44. The lower inner peripheral fastening holes 442 are an example of holes for fastening the bearing 6 and the lower bracket 44. The lower inner peripheral fastening holes 442 are provided, for example, at seven locations. The bearing 6 and the lower bracket 44 are fastened (fixed) by a fastener such as a bolt inserted into the lower inner peripheral fastening holes 442.

[0045] The vertical reinforcing portion 81 has a lower end 811 and an upper end 812. The vertical reinforcing portion 81 projects axially from the back surface of the wall 440 of the lower bracket 44. The vertical reinforcing portion 81 extends radially in the central portion in the circumferential direction of the lower bracket 44, that is, in the central portion in the Y direction. That is, the vertical reinforcing portion 81 extends vertically in the central portion in the circumferential direction of the lower bracket 44, that is, in the central portion in the Y direction. The vertical reinforcing portion 81 extends in the vertical direction passing through the central axis A of the upper bracket 43 and the lower bracket 44.

[0046] The pair of outer reinforcing portions 82 have an inner end 822 and an outer end 821. The pair of outer reinforcing portions 82 project axially from the back surface of the wall 440 of the lower bracket 44. The pair of outer reinforcing portions 82 are located on both sides in the circumferential direction of the central axis A with respect to the vertical reinforcing portion 81. The pair of outer reinforcing portions 82 extend in a direction away from each other as they go upward.

[0047] The pair of outer reinforcing portions 82 each extend, for example, outward in the Y direction of the lower bracket 44 from a position above the intermediate position 813 between the lower end 811 and the upper end 812 of the vertical reinforcing portion 81. Specifically, the pair of outer reinforcing portions 82 are located on both sides in the circumferential direction with respect to the vertical reinforcing portion 81 and extend in a direction away from each other as they go upward. That is, the vertical reinforcing portion 81 is located between the pair of outer reinforcing portions 82 in the circumferential direction. The inner end 822 contacts the vertical reinforcing portion 81. The outer end 821 of the outer reinforcing portion 82 is located in the +Y direction from the upper end 812 of the vertical reinforcing portion 81. The pair of outer reinforcing portions 82 are, for example, plate-shaped ribs and are fixed to the back surface of the wall 430.

[0048] FIG. 3 is a side view showing the bearing bracket 42 according to the embodiment. In the embodiment, the case of the bearing bracket 42 on the +X side will be described as an example. Note that the description of the configuration described in FIG. 2 will be omitted.

[0049] As shown in FIG. 3, in the plurality of reinforcing portions 7, the amount of protrusion from the back surface of the wall 430 increases from the outer first end portions 711, 721, 731 to the inner second end portions 712, 722, 732.

[0050] FIG. 4 is a diagram showing the analysis result of the bearing bracket 42A according to the comparative example. Specifically, FIG. 4 shows the stress distribution of the analysis result when a load is applied to the bearing bracket 42A in the thrust direction along the central axis A of the shaft 30. As shown in FIG. 4, the stress distribution is divided into a region with a high dot density, a region with a low dot density, and an intermediate region between the region with a high dot density and the region with a low dot density. The region with a high dot density is regarded as the region where the stress is the highest, the intermediate region of the dot density is regarded as the region where the stress is lower than that of the region with a high dot density, and the region with a low dot density is regarded as the region where the stress is the lowest.

[0051] The bearing bracket 42A of the comparative example shown in FIG. 4 is different from the bearing bracket 42 of the present embodiment in that the reinforcing portion 7 of the upper bracket 43, the vertical reinforcing portion 81 and the outer reinforcing portion 82 of the lower bracket 44 are not provided.

[0052] As shown in FIG. 4, in the upper bracket 43 of the bearing bracket 42A of the comparative example, the stress of the inner peripheral portion 438 of the upper bracket 43 is high. Further, in the upper bracket 43 of the bearing bracket 42A of the comparative example, the stress on the radially outer side (upper side) of the first measurement hole 434, the second measurement hole 435, and the third measurement hole 436 is high.

[0053] In the lower bracket 44 of the bearing bracket 42A of the comparative example, the stress of the inner peripheral portion 444 of the lower bracket 44 is high. By knowing the stress distribution shown in FIG. 4, the bearing bracket 42 can increase the thickness of the portion where the stress is high and reduce the thickness of the portion where the stress is low. In the present embodiment, based on the above analysis result, as a reinforcing structure of the bearing bracket 42, a reinforcing portion 7, a connecting portion 74, an inner reinforcing portion 75, a vertical reinforcing portion 81, and an outer reinforcing portion 82 are provided.

[0054] As described above, in this embodiment, the rotating electric machine 1 comprises a rotor 3, a stator 2, a bearing 6, and a housing 4. The rotor 3 has a shaft 30. The stator 2 surrounds the rotor 3. The bearing 6 supports the shaft 30 so that it can rotate around the central axis A. The housing 4 has a bearing bracket 42 that supports the bearing 6 and houses the rotor 3 and the stator 2. The bearing bracket 42 comprises a wall 430 and a reinforcing portion 7. The wall 430 has inner circumferential portions 438, 444 that form an opening 420 (first hole) into which the bearing 6 is inserted and support the bearing 6, and outer circumferential portions 437, 443. The wall 430 is provided with a first measuring hole 434 (second hole) that is located radially outside the central axis A relative to the opening 420 and penetrates in the axial direction of the central axis A, and extends in a direction intersecting the axial direction. The reinforcing portion 7 is provided on the wall 430 and has first radially outer ends 711, 721, 731 and second radially inner ends 712, 722, 732. The reinforcing portion 7 extends in a direction intersecting the radial direction of the central axis A and protrudes in the axial direction of the central axis A, with the second ends 712, 722, 732 positioned on the first measurement hole 434 side with respect to the straight lines a1, a2, a3 connecting the first ends 711, 721, 731 and the central axis A.

[0055] With this configuration, the bearing bracket 42, which has a first measuring hole 434 in addition to the opening 420 into which the shaft 30 is inserted, is equipped with a reinforcing portion 7. The reinforcing portion 7 is equipped with a reinforcing portion 7 in which the second ends 712, 722, and 732 are positioned on the side of the first measuring hole 434 with respect to the straight lines a1, a2, and a3 connecting the first ends 711, 721, and 731 to the central axis A, thereby reinforcing the area around the first measuring hole 434. Therefore, the load-bearing capacity of the bearing bracket 42, which has a first measuring hole 434 (second hole) in addition to the opening 420 (first hole) into which the shaft 30 is inserted, can be improved. For example, the thrust load-bearing capacity of the bearing bracket 42 can be improved.

[0056] In this case, if a rotating electric machine 1 is provided as a drive source for the rollers of a rolling mill that rolls steel plates and the like, a thrust load may be applied from the rollers to the rotating electric machine 1. As can be seen from the above, the rotating electric machine 1 of this embodiment is provided with reinforcing parts 7, etc., as a countermeasure against thrust loads. Another type of rotating electric machine that has a different thrust load countermeasure than the rotating electric machine 1 of this embodiment is the bearing-separated type. In this bearing-separated type of rotating electric machine, the rotating electric machine body, including the housing, and the bearings are arranged separately, so that the thrust load from the rollers is less likely to be applied to the rotating electric machine body. However, in the bearing-separated type of rotating electric machine, because the bearings are separated from the rotating electric machine body, the installation work of the rotating electric machine becomes complicated, requiring a considerable amount of time for installation work, and the manufacturing cost of the rotating electric machine is also high. In contrast, the rotating electric machine 1 of this embodiment improves the load-bearing capacity in the thrust direction of the bearing bracket 42 as a countermeasure against thrust loads, and integrates the housing 4 and the bearing 6 with the bearing bracket 42, so that the time for installation work of the rotating electric machine 1 can be shortened. This will also lead to a reduction in the manufacturing cost of the rotating electric machine 1.

[0057] Furthermore, in this embodiment, in the rotating electric machine 1, for example, the bearing bracket 42 includes a pair of first reinforcing parts 71 and a connecting part 74. The pair of first reinforcing parts 71 are provided on walls 430 located on both sides in the circumferential direction of the central axis A with respect to the first measuring hole 434. The connecting part 74 protrudes in the axial direction and connects the pair of first reinforcing parts 71.

[0058] With this configuration, the connection portion 74 can further reinforce the area around the first measurement hole 434. In addition, the connection portion 74 can also increase the strength of the pair of first reinforcing portions 71.

[0059] Furthermore, in this embodiment, in the rotating electric machine 1, for example, the bearing bracket 42 is provided with an inner reinforcing portion 75. The inner reinforcing portion 75 is provided on the wall 430, protrudes radially inward from the reinforcing portion 7, and extends along the periphery of the opening 420.

[0060] With this configuration, the inner reinforcing portion 75 can reinforce the area around the opening 420. Therefore, the load-bearing capacity of the bearing bracket 42 can be improved.

[0061] Furthermore, in this embodiment, in the rotating electric machine 1, for example, the bearing bracket 42 includes a pair of second reinforcing parts 72 and a pair of third reinforcing parts 73. The pair of second reinforcing parts 72 are located on both sides in the circumferential direction relative to the pair of first reinforcing parts 71. The pair of third reinforcing parts 73 are located on both sides in the circumferential direction relative to the pair of second reinforcing parts 72.

[0062] With this configuration, a second reinforcing portion 72 and a third reinforcing portion 73 can be provided in accordance with the areas of high stress on the bearing bracket 42.

[0063] Furthermore, in this embodiment, in the rotating electric machine 1, for example, the connecting portion 74 is located radially outward with respect to the first measuring hole 434. The inner reinforcing portion 75 is located radially inward with respect to the first measuring hole 434.

[0064] With this configuration, the connection portion 74, the inner reinforcing portion 75, and the first reinforcing portion 71 can further reinforce the area around the first measurement hole 434.

[0065] Furthermore, in this embodiment, in the rotating electric machine 1, for example, the amount of protrusion of the reinforcing portion 7 increases from the first ends 711, 721, 731 to the second ends 712, 722, 732.

[0066] With this configuration, the inner circumference 438, 444 of the bearing bracket 42, where stress is high, can be reinforced. Furthermore, the thickness of the first outer ends 711, 721, 731 can be reduced, thus reducing the amount of material used.

[0067] Furthermore, in this embodiment, in the rotating electric machine 1, for example, the bearing bracket 42 has an upper bracket 43 and a lower bracket 44 located below the upper bracket 43. The opening 420, inner circumference 438, 444, outer circumference 437, 443, and walls 430, 440 are provided across the upper bracket 43 and the lower bracket 44. The first measuring hole 434 and the reinforcing portion 7 are provided in the upper bracket 43.

[0068] With this configuration, the upper bracket 43, which is provided with the first measurement hole 434, can be reinforced by the reinforcing part 7.

[0069] Furthermore, in this embodiment, in the rotating electric machine 1, for example, the bearing bracket 42 includes a pair of first reinforcing parts 71, a pair of second reinforcing parts 72, and a pair of third reinforcing parts 73. The pair of first reinforcing parts 71 are located on both sides in the circumferential direction of the central axis A with respect to the first measuring hole 434. The pair of second reinforcing parts 72 are located on both sides in the circumferential direction of the pair of first reinforcing parts 71. The pair of third reinforcing parts 73 are located on both sides in the circumferential direction of the pair of second reinforcing parts 72. The second end 732 of the third reinforcing part 73 is located above the first end 731 of the third reinforcing part 73.

[0070] With this configuration, the upper bracket 43 can be reinforced in the area where the stress is high.

[0071] Furthermore, in this embodiment, the rotating electric machine 1, for example, the bearing bracket 42 includes a vertical reinforcing portion 81 and a pair of outer reinforcing portions 82. The vertical reinforcing portion 81 is provided on the lower bracket 44, extends radially, and protrudes axially. The pair of outer reinforcing portions 82 are provided on the lower bracket 44, are located on both sides of the central axis A relative to the vertical reinforcing portion 81, and extend in a direction that moves away from each other as it goes upward.

[0072] With this configuration, the inner circumference 444 of the lower bracket 44, where stress is high, can be reinforced by the outer reinforcing portion 82 at a position higher than the intermediate position 813 between the upper end 812 and the lower end 811 of the vertical reinforcing portion 81.

[0073] The embodiments of the present invention described above are not intended to limit the scope of the invention, but are merely examples that fall within the scope of the invention. Some embodiments of the present invention may be modified, omitted, or added to the embodiments described above, for example, with respect to at least some of the specific uses, structures, shapes, functions, and effects, without departing from the spirit of the invention.

[0074] 1... Rotating electric machine, 2... Stator, 3... Rotor, 4... Housing, 6... Bearing, 7... Reinforcement part, 30... Shaft, 42... Bearing bracket, 43, 45... Upper bracket, 44, 46... Lower bracket, 71... First reinforcement part, 72... Second reinforcement part, 73... Third reinforcement part, 74... Connection part, 75... Inner reinforcement part, 81... Vertical reinforcement part, 82... Outer reinforcement part, 420... Opening (first hole), 430, 440... Wall, 434... First measuring hole (second hole), 437, 443... Outer circumference, 438, 444... Inner circumference, 711, 721, 731... First end, 712, 722, 732... Second end.

Claims

1. A rotating electric machine comprising: a rotor having a shaft; a stator surrounding the rotor; a bearing supporting the shaft so as to be rotatable about a central axis; and a housing having a bearing bracket supporting the bearing, wherein the bearing bracket has an inner circumferential portion that forms a first hole into which the bearing is inserted and supports the bearing, and an outer circumferential portion, and has a second hole that is located radially outward from the central axis relative to the first hole and penetrates in the axial direction of the central axis, and extends in a direction intersecting the axial direction; and a reinforcing portion provided on the wall, having a first end on the radially outward side and a second end on the radially inward side, extending in a direction intersecting the radial direction of the central axis and protruding in the axial direction of the central axis, with the second end positioned on the second hole side with respect to a straight line connecting the first end and the central axis.

2. The rotating electric machine according to claim 1, wherein the bearing bracket comprises a pair of first reinforcing parts located on both sides of the central axis in the circumferential direction relative to the second hole, and a connecting part provided on the wall, projecting in the axial direction and connecting the pair of first reinforcing parts.

3. The rotating electric machine according to claim 2, wherein the bearing bracket is provided on the wall and includes an inner reinforcing portion that protrudes radially inward from the reinforcing portion in the radial direction and extends along the circumference of the first hole.

4. The rotating electric machine according to claim 2, wherein the bearing bracket comprises a pair of second reinforcing parts located on both sides in the circumferential direction relative to the pair of first reinforcing parts, and a pair of third reinforcing parts located on both sides in the circumferential direction relative to the pair of second reinforcing parts.

5. The rotating electric machine according to claim 3, wherein the connecting portion is located radially outward with respect to the second hole, and the inner reinforcing portion is located radially inward with respect to the second hole.

6. The reinforcing portion has an increasing protrusion from the first end to the second end, the rotating electric machine according to claim 1.

7. The rotating electric machine according to claim 1, wherein the bearing bracket comprises an upper bracket and a lower bracket located below the upper bracket, the first hole, the inner circumference, the outer circumference, and the wall are provided across the upper bracket and the lower bracket, and the second hole and the reinforcing portion are provided on the upper bracket.

8. The rotating electric machine according to claim 7, wherein the bearing bracket comprises: a pair of first reinforcing parts located on both sides of the central axis in the circumferential direction with respect to the second hole; a pair of second reinforcing parts located on both sides of the pair of first reinforcing parts in the circumferential direction; and a pair of third reinforcing parts located on both sides of the pair of second reinforcing parts in the circumferential direction, wherein the second ends of the pair of third reinforcing parts are located above the first ends of the pair of third reinforcing parts.

9. The rotating electric machine according to claim 7, wherein the bearing bracket comprises: a vertical reinforcing portion provided on the lower bracket, extending radially and protruding axially; and a pair of outer reinforcing portions provided on the lower bracket, located on both sides of the central axis in the circumferential direction relative to the vertical reinforcing portion, and extending in a direction away from each other as it moves upward.

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