Rotary electric machine

Abstract

To obtain a rotary electric machine capable of reducing explosion pressure when explosion occurs in a housing.SOLUTION: The rotary electric machine includes a housing, a stator, a rotor, and a bearing. The housing includes a tubular frame and a bracket fitted to an end portion of the frame. The rotor includes a rotor core located inside the stator and a shaft that rotates integrally with the rotor core. The bearing is supported by the bracket and rotatably supports the shaft with respect to the housing. The bracket includes an outer peripheral portion coupled to an end portion of the frame, an inner peripheral portion supporting the bearing, and a wall portion extending between the outer peripheral portion and the inner peripheral portion. The wall portion has a curved protrusion protruding toward the inside of the housing.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] Conventionally, a rotating electric machine has been known that includes a rotor, a stator, and a housing that houses the rotor and the stator. A pressure-resistant explosion-proof rotating electric machine, which is one type of rotating electric machine, is designed to prevent sparks from reaching the outside of the housing when a gas explosion occurs inside the housing of the rotating electric machine, for example. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Utility Model Application Publication No. 61-104750 Summary of the Invention [Problem to be solved by the invention]

[0004] In this type of rotating electrical machine, it would be beneficial if the explosion pressure could be reduced in the event of an explosion inside the housing.

[0005] One example of a problem to be solved by the present invention is to provide a rotating electric machine capable of reducing explosion pressure in the event of an explosion inside a housing. [Means for solving the problem]

[0006] A rotating electric machine according to an embodiment of the present invention includes a housing, a stator, a rotor, and a bearing. The housing has a cylindrical frame and a bracket fitted to an end of the frame. The stator is housed in the housing. The rotor has a rotor core positioned inside the stator and a shaft that rotates integrally with the rotor core. The bearing is supported by the bracket and rotatably supports the shaft relative to the housing. The bracket has an outer periphery coupled to the end of the frame, an inner periphery that supports the bearing, and a wall portion extending between the outer periphery and the inner periphery. The wall portion has a curved protrusion that protrudes toward the inside of the housing. [Effects of the Invention]

[0007] According to the rotating electric machine of the present invention, it is possible to obtain a rotating electric machine that can reduce the explosion pressure when an explosion occurs inside the housing. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a cross-sectional view schematically showing a rotating electric machine according to an embodiment, showing half of the rotating electric machine. [Figure 2] FIG. 2 is a cross-sectional view showing a part of the rotating electric machine according to the embodiment. [Figure 3] FIG. 3 is a cross-sectional view showing a part of a bracket in a rotating electric machine according to a modified example of the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] The rotating electric machine 1 according to this embodiment will be described below with reference to the drawings. The configuration of the embodiment described below, as well as the actions and results (effects) brought about by this configuration, are merely examples and are not limited to the following description. Note that in this specification, ordinal numbers are used only to distinguish between parts and components, and do not indicate order or priority.

[0010] Furthermore, the drawings are schematic, and the dimensional relationships and ratios of elements may differ from reality. Furthermore, the drawings may contain parts with different dimensional relationships and ratios. Furthermore, in this specification, ordinal numbers are used only to distinguish between parts, members, locations, positions, directions, etc., and do not indicate order or priority.

[0011] 1 is a cross-sectional view schematically showing a rotating electric machine 1 according to this embodiment, illustrating half of the rotating electric machine 1. The rotating electric machine 1 according to this embodiment is, for example, a pressure-resistant explosion-proof rotating electric machine. The rotating electric machine 1 may be a motor or a generator.

[0012] 1, the rotating electric machine 1 includes a stator 11, a rotor 12, a housing 14, two bearings 15, a terminal box 16, a plurality of cables 17, an outer fan 18, an outer fan cover 19, and terminal members 24. In the rotating electric machine 1, the rotor 12 rotates around a rotation center axis Ax. The rotation center axis Ax is the center of rotation of the rotor 12 (shaft 121) in the rotating electric machine 1, and is, for example, an imaginary line passing through the center of the rotor 12 (shaft 121).

[0013] In the following description, for convenience, the axial direction, radial direction, and circumferential direction of the rotation center axis Ax are defined. The axial direction is the direction along the rotation center axis Ax. The radial direction is the direction perpendicular to the rotation center axis Ax. The circumferential direction is the direction around the rotation center axis Ax. In the following description, unless otherwise specified, the axial direction, radial direction, and circumferential direction are the axial direction, radial direction, and circumferential direction of the rotation center axis Ax.

[0014] The stator 11 has a stator core 111 and a stator winding 112. The stator core 111 is fixed to the housing 14. The stator core 111 is formed in a substantially cylindrical shape surrounding the central axis of rotation Ax. The stator winding 112 passes through a plurality of slots (not shown) formed in the stator core 111 so as to extend in the axial direction, and is fixed to the stator core 111.

[0015] The rotor 12 has a shaft 121, a rotor core 122, and a conductor 123. The shaft 121 is supported by the housing 14 via two bearings 15 so as to be rotatable around a central axis of rotation Ax surrounded by the stator 11. In other words, the two bearings 15 support the shaft 121 rotatably relative to the housing 14.

[0016] The shaft 121 extends in the axial direction along the central axis of rotation Ax so as to penetrate the housing 14. A portion of the shaft 121 between both axial end portions 121a is housed in the housing 14. On the other hand, both axial end portions 121a of the shaft 121 protrude from the housing 14 to the outside.

[0017] One end 121a of the shaft 121 is coupled to, for example, various external devices, so that the rotation of the shaft 121 drives the external devices.

[0018] The rotor core 122 is formed in a substantially cylindrical shape extending in the axial direction, and is disposed substantially concentrically with the stator 11. The rotor core 122 is disposed inside the stator 11 via a gap. The rotor core 122 is attached to the shaft 121 in a portion between both axial end portions 121a. Therefore, the rotor core 122 rotates integrally with the shaft 121.

[0019] The conductors 123 include, for example, conductor bars 123a that pass through the rotor core 122 in the axial direction, and short-circuit rings that are connected to the axial ends of all of the conductor bars 123a.

[0020] The stator 11 and the rotor core 122 are not limited to the above configuration as long as they can generate a rotational force by an electromagnetic force. For example, the rotor core 122 may have a magnet.

[0021] The housing 14 is formed, for example, in a box shape from metal. However, the housing 14 may be formed from other materials. An accommodation chamber 30 is provided inside the housing 14. The accommodation chamber 30 is a substantially cylindrical space extending in the axial direction. However, the accommodation chamber 30 is not limited to being cylindrical, and may have other shapes. The accommodation chamber 30 accommodates the stator 11, a portion of the shaft 121, and the rotor core 122. That is, the housing 14 accommodates the stator 11, a portion of the shaft 121, and the rotor core 122. Furthermore, the housing 14 supports two bearings 15.

[0022] The outer fan 18 is coupled to the shaft 121 outside the housing 14. This allows the outer fan 18 to rotate integrally with the shaft 121 (rotor 12) around the central axis of rotation Ax. The outer fan 18 is, for example, a centrifugal fan that can cause gas to flow at least radially outward by rotating. As an example, the outer fan 18 can cause gas to flow radially outward and in the axial direction toward the housing 14 by rotating. Note that the outer fan 18 is not limited to the above.

[0023] The outer fan cover 19 is located outside the housing 14 and covers the outer fan 18. The outer fan cover 19 is made of, for example, metal. The outer fan cover 19 is fixed to the axial end of the housing 14. A plurality of air intake holes are provided in the axial end wall of the outer fan cover 19.

[0024] As the external fan 18 rotates, it can draw outside air into the external fan cover 19 through the intake holes in the external fan cover 19. This generates an airflow toward the external fan 18. The airflow of outside air generated by the rotating external fan 18 passes, for example, through a passage provided between the external fan cover 19 and the outer surface of the housing 14 and is released to the outside of the housing 14, and flows axially along the outer peripheral surface 21a of the frame 21 that constitutes the outer surface of the housing 14. In other words, an airflow is generated along the outer surface of the housing 14. This airflow of outside air exchanges heat with the housing 14. As a result, the airflow of outside air cools the stator 11 and the gas in the housing chamber 30 of the housing 14 via the housing 14. This cools the components housed within the housing 14, such as the rotor 12.

[0025] The terminal member 24 is fixed to the housing 14. The terminal member 24 is formed, for example, in a plate shape. The terminal member 24 is, for example, a member that can be electrically connected to the stator winding 112. The terminal member 24 has a cover 241 and a plurality of terminals 242.

[0026] The cover 241 is formed in a plate shape and is joined to the frame 21 with bolts. The terminals 242 are, for example, conductors that pass through the cover 241. In this embodiment, the multiple terminals 242 are electrically connected to the terminal box 16.

[0027] The terminal box 16 is fixed to the housing 14. As an example, the terminal box 16 is fixed to the housing 14 via terminal members 24. The terminal box 16 is located outside the housing 14. The terminal box 16 has a terminal box housing and an accommodated component. The terminal box housing is fixed to the housing 14.

[0028] The accommodated component is accommodated inside the terminal box housing. The accommodated component is, for example, a terminal block and has a base and terminals. The terminal of the accommodated component is electrically connected to a connection target via terminal 242 and cable 17. The terminal of the accommodated component is also electrically connected to an external device via an external connection member. That is, terminal box 16 is electrically connected to a connection target inside housing 14 via terminal member 24. The connection target includes stator winding 112. Note that the connection target may be various sensors provided inside housing 14 in addition to stator winding 112. The sensor may include, for example, a temperature sensor, a current sensor, etc.

[0029] The cables 17 electrically connect, for example, the stator windings 112, sensors arranged in the accommodating chamber 30, and the plurality of terminals 242. In other words, the terminal box 16 is electrically connected to the stator windings 112, sensors arranged in the accommodating chamber 30, and the like via the plurality of terminals 242 and the cables 17.

[0030] The housing 14 has a frame 21, two brackets 22, and two oil throwers 23.

[0031] The frame 21 and the two brackets 22 surround the accommodation chamber 30. In other words, the frame 21 and the two brackets 22 form the accommodation chamber 30.

[0032] The frame 21 is formed in a substantially cylindrical shape around the central axis of rotation Ax. More specifically, the frame 21 is formed with a through-hole 50 that passes through the frame 21 in the axial direction. The through-hole 50 includes the accommodation chamber 30. The frame 21 surrounds the stator 11, the rotor core 122, and the accommodation chamber 30. In other words, the frame 21 is disposed substantially concentrically with the stator 11 and the rotor core 122, and is fixed to the stator 11. The frame 21 is not limited to being cylindrical, and may have another shape.

[0033] 2 is a cross-sectional view showing a portion of the rotating electric machine 1 of this embodiment. Note that some components are omitted in FIG. 2. As shown in FIGS. 1 and 2, the frame 21 has an outer peripheral surface 21a and an inner peripheral surface 21b. The outer peripheral surface 21a is a substantially cylindrical curved surface extending in the axial direction. The outer peripheral surface 21a faces the outside of the frame 21.

[0034] The inner circumferential surface 21b is a substantially cylindrical curved surface extending in the axial direction. The inner circumferential surface 21b forms (defines or defines) the through hole 50. The inner circumferential surface 21b faces inward in the radial direction. In other words, the inner circumferential surface 21b faces the inside of the through hole 50. The inner circumferential surface 21b surrounds the through hole 50.

[0035] The outer peripheral surface 21a and the inner peripheral surface 21b extend to both end portions 21c of the frame 21 in the axial direction.

[0036] The end portion 21c has a joint surface 21d. The joint surface 21d is connected to the end of the inner circumferential surface 21b in the axial outward direction Dxo. The axial outward direction Dxo is a direction toward the outside of the housing 14 in the axial direction and is included in the axial direction. The opposite direction of the axial outward direction Dxo is the axial inward direction Dxi. The axial inward direction Dxi is a direction toward the inside of the housing 14 in the axial direction and is included in the axial direction. The joint surface 21d is, for example, a substantially annular plane extending radially outward from the end of the inner circumferential surface 21b. The joint surface 21d faces the axial outward direction Dxo. The axial outward direction Dxo is perpendicular to the direction in which the inner circumferential surface 21b faces. Note that the joint surface 21d may face in another direction intersecting the direction in which the inner circumferential surface 21b faces.

[0037] As shown in FIG. 1, two terminal bases 211, a hanging portion 212, a rib 213, and a plurality of fins 214 are provided on an outer peripheral surface 21a of the frame 21.

[0038] The terminal seats 211 protrude radially outward from the outer peripheral surface 21a of the frame 21. The two terminal seats 211 are positioned axially spaced apart from each other. The terminal seats 211 are also referred to as protrusions. The terminal seats 211 have a tip surface 211c. The terminal box 16 is fixed to this tip surface 211c. The terminal seats 211 are also referred to as protrusions.

[0039] 2, the terminal base 211 is provided with a through hole 31. The through hole 31 is a hole that penetrates the terminal base 211 in the radial direction. The through hole 31 penetrates the frame 21 and the terminal base 211 in the radial direction, and connects the accommodating chamber 30 to the outside of the housing 14.

[0040] The through hole 31 includes a first hole portion 31a and a second hole portion 31b. The first hole portion 31a is provided in the terminal base 211. The second hole portion 31b is provided in the frame 21 and connected to the first hole portion 31a. That is, the second hole portion 31b is located radially inward of the first hole portion 31a. The diameter of the first hole portion 31a is larger than the diameter of the second hole portion 31b. In other words, the diameter of the second hole portion 31b is smaller than the diameter of the first hole portion 31a. This forms a step in the through hole 31. As shown in FIG. 1 , the through hole 31 accommodates a terminal member 24. Specifically, the terminal member 24 is accommodated in the first hole portion 31a of the through hole 31.

[0041] 1, the suspending portion 212 protrudes radially outward from the outer peripheral surface 21a of the frame 21. The suspending portion 212 is provided between the two terminal seats 211. A hook or the like of a lifting device is hooked onto the suspending portion 212. The lifting device can lift the suspending portion 212 and thus the rotating electric machine 1.

[0042] The rib 213 protrudes radially outward from the outer circumferential surface 21a of the frame 21. The rib 213 extends between the hanging portion 212 and the two terminal seats 211.

[0043] The multiple fins 214 protrude radially outward from the outer circumferential surface 21a of the frame 21. The airflow generated by the external fan 18 flows along the outer surfaces of the fins 214.

[0044] As shown in FIG. 2, the frame 21 further has a protruding portion 21e. The protruding portion 21e protrudes from a radially inner end portion 211b of the inner peripheral surface 211a of the terminal base 211. The protruding portion 21e is formed in a ring shape surrounding the second hole portion 31b. In other words, the protruding portion 21e forms the second hole portion 31b. The protruding portion 21e supports the terminal member 24 on the radially inner side relative to the terminal member 24 (FIG. 1). More specifically, the protruding portion 21e has a support surface 21f that supports the terminal member 24. The support surface 21f is the radially outer surface of the protruding portion 21e. The support surface 21f is an example of a first surface. The protruding portion 21e is also referred to as a support portion.

[0045] The thickness t1 of the protruding portion 21e in the protruding direction D1 of the terminal base 211 is equal to or less than the thickness t2 of the outer portion 21g, which is the portion of the frame 21 that is outside (around) the terminal base 211. In other words, the thickness t1 of the protruding portion 21e in the protruding direction D1 of the terminal base 211 is equal to or less than the thickness t2 of the frame 21 outside the terminal base 211.

[0046] Furthermore, radial position P1 of support surface 21f of protruding portion 21e coincides with either position P2 of outer peripheral surface 21a of outer frame 21 outside terminal base 211, i.e., position P2 of outer peripheral surface 21a of outer portion 21g, or position P3 of inner peripheral surface 21b of frame 21 outside terminal base 211, i.e., position P3 of outer portion 21g. Fig. 2 shows an example in which radial position P1 of support surface 21f coincides with either position P2 of outer peripheral surface 21a of outer peripheral surface 21a of outer frame 21 outside terminal base 211, i.e., position P2 of outer peripheral surface 21a of outer portion 21g, or position P3 of inner peripheral surface 21b of frame 21 outside terminal base 211, i.e., position P3 of outer portion 21g.

[0047] The protruding portion 21e is provided with a surface 21h. The surface 21h is a substantially annular flat surface that extends radially inward from the end of the inner circumferential surface 21b. The surface 21h faces outward in the axial direction Dxo.

[0048] 1, the two brackets 22 are coupled (fixed) to the frame 21 in a state where they are fitted onto both end portions 21c of the frame 21 in the axial direction. In this way, the brackets 22 close both end portions 21c of the frame 21. The brackets 22 are fixed to the frame 21 by, for example, bolts. Fins 215 are provided on the outer surfaces 22a of the brackets 22.

[0049] As shown in Fig. 2, the bracket 22 has an outer peripheral portion 221, an inner peripheral portion 222, and a wall portion 223. The outer peripheral portion 221 is the radially outer portion of the bracket 22, and is fitted (coupled) to the end portion 21c of the frame 21. The inner peripheral portion 222 is the radially inner portion of the bracket 22, and supports the bearing 15. The wall portion 223 is a portion that spans the outer peripheral portion 221 and the inner peripheral portion 222. Note that Fig. 2 does not illustrate the ribs 213, fins 214, 215, etc. The outer peripheral portion 221 is also referred to as a fitting portion or a coupling portion, and the inner peripheral portion 222 is also referred to as a support portion.

[0050] The outer peripheral portion 221 is coupled (fixed) to the end portion 21c of the frame 21. The outer peripheral portion 221 has a base portion 221a and a protrusion 221b.

[0051] The base portion 221a has a joint surface 221c. The joint surface 221c faces inward in the axial direction Dxi. The joint surface 221c faces the joint surface 21d of the frame 21 in the axial direction and covers the joint surface 21d.

[0052] The protrusion 221b protrudes inward in the axial direction Dxi from the radially inner end of the joint surface 21d of the base portion 221a. That is, the protrusion 221b protrudes into the accommodation chamber 30 from the radially inner end of the joint surface 21d of the base portion 221a. The protrusion 221b is formed in a cylindrical shape around the rotation center axis Ax. The protrusion 221b is fitted into the end portion 21c of the frame 21. A tip surface 221i of the protrusion 221b faces the surface 21h in the axial direction.

[0053] The protrusion 221b has an outer peripheral surface 221d. The outer peripheral surface 221d is a substantially cylindrical curved surface extending in the axial direction. The diameter of the outer peripheral surface 221d is equal to or slightly shorter than the diameter of the inner peripheral surface 21b at the end 21c of the frame 21. Furthermore, the length of the outer peripheral surface 221d in the axial direction is substantially equal to the length of the inner peripheral surface 21b.

[0054] The outer peripheral surface 221d faces radially outward. In other words, the outer peripheral surface 221d faces the inner peripheral surface 21b of the frame 21. The outer peripheral surface 221d may be in contact with the inner peripheral surface 21b or may be slightly spaced apart from the inner peripheral surface 21b. The outer peripheral surface 221d and the inner peripheral surface 21b are arranged substantially concentrically and substantially parallel to each other.

[0055] The inner circumferential portion 222 has a base portion 222a and a protrusion 222b. The base portion 222a surrounds the bearing 15 and supports the bearing 15.

[0056] The protrusion 221b protrudes inward in the axial direction Dxi from the base portion 222a. That is, the protrusion 222b protrudes from the base portion 222a into the accommodation chamber 30. The protrusion 222b is formed in a cylindrical shape around the rotation center axis Ax. The protrusion 222b surrounds and supports the oil thrower 23.

[0057] The wall portion 223 has a protrusion 223a. The protrusion 223a protrudes inward of the housing 14, i.e., toward the accommodation chamber 30, and is formed in a curved shape. The protrusion 223a is curved such that its radial width narrows toward the top 223d of the protrusion 223a. The protrusion 223a is, for example, a part of a wave shape. The protrusion 223a is annular about the rotation center axis Ax, i.e., about the shaft 121.

[0058] The convex portion 223a has a convex surface 223b and a concave surface 223c. The convex surface 223b is a surface that faces the interior of the housing 14, i.e., the storage chamber 30. The convex surface 223b protrudes inward of the housing 14, i.e., toward the storage chamber 30, and is formed in a curved shape. The convex surface 223b is a smoothly curved surface whose radial width narrows toward the apex 223d of the convex portion 223a. The concave surface 223c is provided on the opposite side of the convex surface 223b and is aligned with the convex surface 223b in the axial direction. The concave surface 223c is a surface that faces the exterior of the housing 14. The concave surface 223c is concave toward the interior of the housing 14 (the storage chamber 30) and is formed in a curved shape. The concave surface 223c is a smoothly curved surface whose radial width narrows toward the apex 223d of the convex portion 223a. The concave surface 223c is generally aligned with the convex surface 223b.

[0059] Furthermore, the protrusions 223a are spaced apart from the stator 11 and the rotor 12. The tops 223d of the protrusions 223a are aligned with the stator windings 112 of the stator 11 at an interval in the axial direction.

[0060] Furthermore, as shown in FIG. 1 , an opening 32 is provided in the bracket 22. More specifically, the opening 32 is provided in the inner peripheral portion 222 of the bracket 22. The opening 32 opens in the axial direction in the bracket 22. The opening 32 connects the outside of the housing 14 with the storage chamber 30. Note that the opening 32 does not have to connect the outside of the housing 14 with the storage chamber 30 by itself. For example, the opening 32 may be provided in the middle of a passage that connects the outside of the housing 14 with the storage chamber 30 by itself. The shaft 121 is arranged to pass through the opening 32. In other words, the shaft 121 passes through the bracket 22 in the axial direction.

[0061] The oil throwers 23 are formed in an annular shape that intersects with the axial direction. The oil throwers 23 are located inside the housing 14 relative to the brackets 22. Each oil thrower 23 is connected to the corresponding bracket 22 with a bolt. The shaft 121 passes through the oil throwers 23. The oil throwers 23 restrict the movement of oil inside the housing 14 to the outside of the housing 14.

[0062] A bearing chamber 34 is provided between the bracket 22 and an oil thrower 23 connected to the bracket 22 .

[0063] The bearing 15 is accommodated in the bearing chamber 34. The bearing 15 is attached to the bracket 22 in the bearing chamber 34, for example. The bearing 15 supports the shaft 121 rotatably around the rotation center axis Ax.

[0064] The frame 21, bracket 22, oil thrower 23, terminal member 24, and terminal seat 211 are joined together by a spigot joint. A spigot joint is also called a spigot joint. In a spigot joint, a protrusion or plug on one member is fitted into a recess or hole on the other member. However, the frame 21, bracket 22, oil thrower 23, terminal member 24, and terminal seat 211 may also be joined together by other methods.

[0065] The rotating electric machine 1, which is an explosion-proof motor configured as described above, can prevent sparks from reaching the outside of the housing 14 even if a gas explosion occurs in the accommodation chamber 30. The following description will be given of the case where an explosion occurs in the accommodation chamber 30. The rotating electric machine 1 has various configurations that can suppress the occurrence of an explosion in the accommodation chamber 30.

[0066] As shown in FIG. 2, gaps G1, G2, and G3 may be provided between the frame 21 and the bracket 22. Gap G1 is provided between the joint surface 21d and the joint surface 221c. Gap G2 is provided between the inner peripheral surface 21b and the outer peripheral surface 221d. Gap G3 is provided between the surface 21h provided on the protruding portion 21e and the tip surface 221i of the convex portion 221b. The surfaces that form gaps G1, G2, and G3 are also referred to as explosion-proof surfaces. Note that explosion-proof surfaces may be provided in places other than those described above.

[0067] Gap G1 extends in the radial direction and communicates with the outside of housing 14. Gap G3 extends in the radial direction and communicates with storage chamber 30. Gap G2 extends in the axial direction and communicates between gap G1 and gap G3. For this reason, there is a risk that storage chamber 30 will communicate with the outside of housing 14 through gaps G1, G2, and G3.

[0068] If an explosion occurs in the housing chamber 30, sparks may enter the gap G3. However, the sparks collide with the inner circumferential surface 21b at the portion where the gap G3 and the gap G2 are connected, causing a pressure loss. The sparks, whose pressure has been reduced, travel in the axial direction through the gap G2, which is longer than the gap G3. Therefore, the rotating electric machine 1 can extinguish the sparks in the gap G2.

[0069] As described above, the rotating electric machine 1 of the embodiment includes the housing 14, the stator 11, the rotor 12, and the bearing 15. The housing 14 has a cylindrical frame 21 and a bracket 22 fitted to the end 21c of the frame 21. The stator 11 is housed in the housing 14. The rotor 12 has a rotor core 122 located inside the stator 11 and a shaft 121 that rotates integrally with the rotor core 122. The bearing 15 is supported by the bracket 22 and supports the shaft 121 rotatably relative to the housing 14. The bracket 22 has an outer circumferential portion 221 connected to the end 21c of the frame 21, an inner circumferential portion 222 that supports the bearing 15, and a wall portion 223 that extends between the outer circumferential portion 221 and the inner circumferential portion 222. The wall portion 223 has a curved protrusion 223a that protrudes toward the inside of the housing 14.

[0070] According to this configuration, wall portion 223 has curved protrusion 223a that protrudes inward of housing 14, so the volume inside housing 14 can be reduced compared to a configuration in which protrusion 223a is not provided, and therefore the amount of gas inside housing 14 can be reduced. The volume inside housing 14 is proportional to the explosion pressure inside housing 14 in the event of a gas explosion inside housing 14. Therefore, even if a gas explosion occurs inside housing 14, the explosion pressure inside housing 14 can be reduced.

[0071] Furthermore, with the above configuration, the explosion pressure inside the housing 14 can be reduced, and the thickness (wall thickness) of the frame 21 and the bracket 22 of the housing 14 can be reduced, thereby reducing the material cost of the housing 14 and, ultimately, the cost of the rotating electric machine 1.

[0072] Furthermore, with the above configuration, since the protrusions 223a are provided, the surface area of ​​the housing 14 can be increased compared to a configuration in which the protrusions 223a are not provided. This improves the heat dissipation performance of the housing 14, thereby improving the cooling performance of the stator 11 and the rotor 12.

[0073] The protrusion 223a is annular and surrounds the shaft 121.

[0074] With this configuration, the volume inside the housing 14 can be further reduced, and therefore the amount of gas inside the housing 14 can be further reduced. Therefore, even if a gas explosion occurs inside the housing 14, the explosion pressure inside the housing 14 can be further reduced.

[0075] The rotating electric machine 1 also includes a terminal box 16 and a terminal member 24. The terminal member 24 electrically connects the terminal box 16 to a connection target (e.g., the stator winding 112) inside the housing 14. The housing 14 has a terminal base 211 and a protruding portion 21e. The terminal base 211 has a tip surface 211c to which the terminal box 16 is attached, houses the terminal member 24 inside, and is tubular protruding from the outer peripheral surface 21a of the frame 21 in the radial direction of the shaft 121. The protruding portion 21e protrudes from an end portion 211b on the radially inner side of the terminal base 211 and supports the terminal member 24 on the radially inner side relative to the terminal member 24. A thickness t1 of the protruding portion 21e in the protruding direction D1 of the terminal base 211 is equal to or smaller than a thickness t2 of the frame 21 outside the terminal base 211. The radial position P1 of the radially outer support surface 21f (first surface) of the protrusion 21e coincides with the position of the outer peripheral surface 21a or the position of the outer peripheral surface 21a between the position P2 of the outer peripheral surface 21a of the frame 21 outside the terminal base 211 and the position P3 of the inner peripheral surface 21b of the frame 21 outside the terminal base 211.

[0076] This configuration ensures the strength and rigidity of the protruding portion 21e, and also reduces the height h1 (FIG. 2), which is the amount of protrusion of the terminal base 211 from the outer peripheral surface 21a of the frame 21, compared to a configuration in which the support surface 21f of the protruding portion 21e is located radially outward of the position of the outer peripheral surface 21a of the frame 21, i.e., a configuration in which the protruding portion 21e is provided inside the terminal base 211. This reduces the volume inside the terminal base 211, and therefore the amount of gas inside the housing 14. This means that even if a gas explosion occurs inside the housing 14, the explosion pressure inside the housing 14 can be reduced.

[0077] Furthermore, the protrusions 223a are aligned with the stator 11 at an interval in the axial direction.

[0078] With this configuration, heat from stator 11 can be dissipated to the outside of housing 14 via protrusions 223a, thereby improving the cooling performance of stator 11.

[0079] Next, a modified example will be described. Fig. 3 is a cross-sectional view showing a part of the bracket 22 in the rotating electric machine 1 according to a modified example of this embodiment.

[0080] As shown in FIG. 3, the wall portion 223 of the bracket 22 in the rotating electric machine 1 of the modified example has a protrusion 223a and a protrusion 223e. The protrusion 223e is curved in a convex shape toward the outside of the housing 14 (FIG. 1). The protrusion 223e is, for example, located radially outward of the protrusion 223a and connected to the protrusion 223a. The protrusion 223e has an annular shape around the rotation center axis Ax, i.e., around the shaft 121. The amount of protrusion of the protrusion 223e in the axial direction is smaller than the amount of protrusion of the protrusion 223a. In other words, the amount of protrusion of the protrusion 223e in the axial direction is larger than the amount of protrusion of the protrusion 223e in the axial direction. The protrusions 223a and 223e form a wave shape. In other words, the protrusions 223a and 223e are each part of the wave shape. The wave shape may have one cycle or two or more cycles. The protruding portion 223e may be located radially inward of the protruding portion 223a and connected to the protruding portion 223a.

[0081] According to this configuration, even in the configuration in which convex portion 223e is provided, convex portion 223a is provided, so compared to a configuration in which convex portion 223a is not provided, the volume inside housing 14 can be reduced, and therefore the amount of gas inside housing 14 can be reduced. Therefore, even if a gas explosion occurs inside housing 14, the explosion pressure inside housing 14 can be reduced.

[0082] Furthermore, with the above configuration, the surface area of ​​the housing 14 can be increased compared to a configuration in which the protrusions 223a and 223e are not provided. Therefore, the heat dissipation performance of the housing 14 can be improved, and the cooling performance of the stator 11 and the rotor 12 can be improved.

[0083] Although the embodiments of the present invention have been described above, the above embodiments are merely examples and are not intended to limit the scope of the invention. The above embodiments can be implemented in various other forms, and various omissions, substitutions, combinations, and modifications can be made without departing from the spirit of the invention. Furthermore, the specifications of each configuration, shape, and the like (structure, type, direction, format, size, length, width, thickness, height, number, arrangement, position, material, etc.) can be modified as appropriate. [Explanation of symbols]

[0084] 1...rotating electric machine, 11...stator, 12...rotor, 14...casing, 15...bearing, 16...terminal box, 21...frame, 21c...end, 21e...projection portion, 21f...support surface (first surface), 22...bracket, 24...terminal member, 121...shaft, 122...rotor core, 211...terminal seat, 211c...tip surface, 221...outer periphery, 222...inner periphery, 223...wall portion, 223a...convex portion, D1...projection direction, t1, t2...thickness, P1, P2, P3...position.

Claims

1. a housing having a cylindrical frame and a bracket fitted to an end of the frame; a stator housed in the housing; a rotor having a rotor core located inside the stator and a shaft that rotates integrally with the rotor core; a bearing supported by the bracket and configured to rotatably support the shaft relative to the housing; Equipped with The bracket is a periphery coupled to the end of the frame; an inner circumferential portion that supports the bearing; a wall portion extending between the outer circumferential portion and the inner circumferential portion; and The wall portion has a curved convex portion that protrudes toward the inside of the housing. Rotating electric motor.

2. The convex portion is annular around the shaft. The rotating electric machine according to claim 1 .

3. Terminal box and a terminal member electrically connecting a connection target in the housing to the terminal box; Equipped with The housing includes: a cylindrical terminal seat having a tip end surface to which the terminal box is attached, accommodating the terminal member therein, and protruding from an outer peripheral surface of the frame in a radial direction of the shaft; a protruding portion that protrudes from an end portion of the terminal seat on the inner side in the radial direction and supports the terminal member on the inner side in the radial direction relative to the terminal member; and a thickness of the protruding portion in a protruding direction of the terminal base is equal to or less than a thickness of the frame on the outside of the terminal base; the radial position of the first surface on the radially outer side of the protruding portion coincides with either the position of the outer peripheral surface of the frame on the outer side of the terminal base or the position of the inner peripheral surface of the frame on the outer side of the terminal base, in the radial direction; The rotating electric machine according to claim 2 .

Images