Rotating electric machine

Abstract

In this embodiment, a rotating electrical machine includes a housing, a screw receiving portion, and an internally threaded portion. The housing includes a first member and a second member. The second member is removed from the first member by moving relative to the first member in a first direction. The first member has a first joining surface. The second member has a second engagement surface facing the first engagement surface and a mounting portion (b). The screw receiving portion is located outside the first engagement surface in a line-of-sight in the first direction. The female thread portion is located outside the second joining surface in a line-of-sight in the first direction.

Description

Technical Field

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

[0002] Conventionally, a known rotating electric machine includes a rotating electric machine main body and a terminal box. A pressure-resistant explosion-proof motor, as one type of rotating electric machine, is designed to prevent sparks from reaching the outside of the housing, for example, when an explosion occurs inside the rotating electric machine.

[0003] Japanese Utility Model Application Publication No. S61-104750 describes a related art.

[0004] In a conventional rotating electric machine called a pressure-resistant explosion-proof motor, in order to prevent sparks generated inside the rotating electric machine from reaching the outside of the housing, a measure has been taken to design the gap connecting the inside and outside of the housing to be long. If the pressure resistance and explosion-proof performance can be further improved, such a rotating electric machine will have advantages.

[0005] An example of the problem to be solved by the present invention is to obtain a rotating electric machine that can further improve pressure resistance and explosion-proof performance. Summary of the Invention

[0006] A rotating electric machine includes a housing, a screw receiving portion, and an internal thread portion. The housing includes a first member and a second member. The first member includes an opening. The second member is installed in the opening to close the opening and can be removed from the first member by moving relative to the first member in a first direction. The screw receiving portion receives the end of an external thread member and is included in the first member. The internal thread portion is included in the second member, is located in the first direction relative to the screw receiving portion, is coupled to the external thread member, and converts the rotational movement of the external thread member in one rotational direction into a linear movement of the second member relative to the first member in the first direction. The first member includes an inner peripheral surface and a first engaging surface. The inner peripheral surface forms the opening. The first engaging surface projects from the inner peripheral surface in a direction intersecting the first direction and is annular. The second member includes a second engaging surface and a mounting portion. The second engaging surface faces the first engaging surface and is annular. The mounting portion projects from the second engaging surface in a direction opposite to the first direction and is installed in the opening. The screw receiving portion is located outside the first engaging surface in the line of sight along the first direction. The internal thread portion is located outside the second engaging surface in the line of sight along the first direction.

[0007] According to the rotating electric machine of the present invention, a rotating electric machine that can further improve pressure resistance and explosion-proof performance can be obtained. Brief Description of the Drawings

[0008] Figure 1 is a front view showing a rotating electric machine according to an embodiment;

[0009] Figure 2 is a front view showing a terminal box of a rotating electric machine according to this embodiment;

[0010] Figure 3 is a sectional view showing the terminal box of this embodiment;

[0011] Figure 4 is a front view showing a housing body of a housing of a terminal box according to this embodiment;

[0012] Figure 5 is a rear view showing a cover of a housing of a terminal box according to this embodiment; and

[0013] Figure 6 is a sectional view showing a separation structure in a terminal box according to this embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0014] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. It should be noted that, in this specification, components according to the embodiments and descriptions of the components can be described in various ways. These components and their descriptions are exemplary and are not limited by the expressions herein. The components can also be designated by names different from those herein. In addition, the components can be described by expressions different from the expressions in this specification.

[0015] In addition, the accompanying drawings are schematic, and the dimensional relationships of the elements, the ratios of the elements, etc. may be different from the actual situation. In addition, the accompanying drawings may include different dimensional relationships or different ratios from each other.

[0016] Figure 1 is a diagram illustrating a rotating electric machine 1 of this embodiment. The rotating electric machine 1 of this embodiment is, for example, a pressure-resistant explosion-proof rotating electric machine. The pressure-resistant explosion-proof rotating electric machine can be a motor or a generator. As Figure 1 shown, the rotating electric machine 1 includes a rotating electric machine main body 2 and a terminal box 3.

[0017] The rotating electric machine main body 2 includes a housing 11, a stator 12, a shaft 13, a rotor 15, and a sensor 16.

[0018] The housing 11 is, for example, a box-shaped structure made of metal. It should be noted that the housing 11 can also be made of another material. The housing 11 houses the stator 12, a part of the shaft 13, the rotor 15, and the sensor 16. The housing 11 is constituted by, for example, a combination of a plurality of members.

[0019] The stator 12 includes a stator core and a stator winding. The stator core is fixed to the housing 11. The stator core is located radially outside the rotor 15 and forms a cylinder around the rotor 15. The stator winding passes through a plurality of slots formed in the stator core in an axially extending manner and is fixed to the stator core.

[0020] The shaft 13 is rotatably supported by the housing 11 via two bearings. In other words, these two bearings rotatably support the shaft 13 relative to the housing 11. The shaft 13 extends through the housing 11. One end of the shaft 13 is coupled to, for example, various external devices. As a result, the rotation of the shaft 13 drives the external devices.

[0021] The rotor 15 is housed inside the housing 11. The rotor 15 is formed in a substantially cylindrical shape extending along the axial direction of the shaft 13 and is arranged substantially coaxially with the stator 12. The rotor 15 is located inside the stator 12 and there is a gap between the rotor 15 and the stator 12. The rotor 15 includes, for example, a plurality of permanent magnets. The rotor 15 is coupled to the shaft 13 and rotates integrally with the shaft 13.

[0022] The stator 12 and the rotor 15 are not limited to the above structures as long as they can generate torque by electromagnetic force. For example, the rotor 15 may include a rotor core made of a magnetic material and conductors attached to the rotor core.

[0023] The sensor 16 can detect, for example, the internal state of the housing 21. The internal state of the housing 21 is, for example, the temperature or humidity inside the housing 21.

[0024] As Figure 1 shown, the terminal box 3 is located outside the rotating electric machine main body 2 and is attached to the housing 11.

[0025] The terminal box 3 includes a housing 21 and a housed member 22. The housing 21 is fixed to the housing 11 of the rotating electric machine main body 2. The housing 21 of the terminal box 3 and the housing 11 of the rotating electric machine main body 2 constitute a housing 4. The housing 4 is also called a casing.

[0026] The housed member 22 is housed inside the housing 21. The housed member 22 is, for example, a terminal base and includes a base and terminals. The terminals of the housed member 22 are electrically connected to the sensor 16 or the stator core of the stator 12 via a cable 23. In addition, the terminals of the housed member 22 are electrically connected to external devices via an external connection member.

[0027] Next, the housing 21 of the terminal box 3 will be described in detail. Figure 2 is a front view of the terminal box 3 of the rotating electric machine 1 according to this embodiment. Figure 3 is a sectional view of the terminal box 3 of this embodiment. Figure 4 is a front view of the housing main body 31 of the housing 21 of the terminal box 3 of this embodiment. Figure 5 is a rear view of the cover 32 in the housing 21 of the terminal box 3 of this embodiment.

[0028] In this specification, for convenience, the X-axis, Y-axis, and Z-axis are defined. The X-axis, Y-axis, and Z-axis are orthogonal to each other.

[0029] In addition, in this specification, the X-direction, Y-direction, and Z-direction are defined. The X-direction is the direction along the X-axis, including the +X direction indicated by the arrow of the X-axis and the -X direction opposite to the arrow of the X-axis. The Y-direction is the direction along the Y-axis, including the +Y direction indicated by the arrow of the Y-axis and the -Y direction opposite to the arrow of the Y-axis. The Z-direction is the direction along the Z-axis, including the +Z direction indicated by the arrow of the Z-axis and the -Z direction opposite to the arrow of the Z-axis.

[0030] As Figure 2 and Figure 3 shown, the housing 21 of the terminal box 3 includes a housing body 31, a cover 32, and a plurality of coupling members 33. The cover 32 is installed in the opening 34 of the housing body 31 to close the opening 34. The cover 32 is detachably fixed to the housing body 31 by coupling members 33 such as bolts. In a state where the coupling members 33 are removed, the cover 32 is removed from the housing body 31 by moving the cover 32 in the +X direction with respect to the housing body 31. The housing body 31 is an example of the first member, and the cover 32 is an example of the second member. The +X direction is an example of the first direction.

[0031] As Figure 3 and Figure 4 shown, the housing body 31 includes a cylindrical portion 31a, an end wall portion 31b, and a fixing portion 31c. The housing body 31 includes an opening 34. The opening 34 is a recess that opens in the +X direction and is recessed in the -X direction. The component 22 to be housed is housed in the opening 34. The opening 34 is closed by the cover 32.

[0032] The cylindrical portion 31a forms a cylinder around the center line L1. Incidentally, the X-axis extends along the center line L1. The cylindrical portion 31a includes a through hole 35. The through hole 35 communicates with the internal space of the housing 11 of the rotary electric machine main body 2. The cable 23 ( Figure 1 ) is inserted into the through hole 35.

[0033] The end wall portion 31b is connected to the end of the cylindrical portion 31a on the -X direction side. The end wall portion 31b extends in a direction (Y-Z plane) intersecting the X direction.

[0034] The fixing portion 31c is connected to the end of the cylindrical portion 31a on the +X direction side. The fixing portion 31c forms an infinite shape (ring shape) around the center line L1. The fixing portion 31c includes a plurality of internal thread portions 45. The internal thread portions 45 are coupled to the coupling members 33.

[0035] The housing body 31 also has an inner peripheral surface 31e and a joint surface 31d. The inner peripheral surface 31e forms a cylindrical surface shape around the center line L1. The inner peripheral surface 31e surrounds the opening 34. In other words, the inner peripheral surface 31e forms the opening 34. The joint surface 31d is also referred to as an explosion-proof surface or a mating surface.

[0036] The joint surface 31d includes a joint surface 31da and a joint surface 31db. The joint surface 31db is included in the fixed portion 31c and forms a cylindrical surface shape around the center line L1. The joint surface 31d constitutes the end portion of the inner peripheral surface 31e on the +X direction side. That is, the joint surface 31db is included in the inner peripheral surface 31e.

[0037] The joint surface 31da is included in the fixed portion 31c and faces the +X direction. The joint surface 31da protrudes from the joint surface 31db (i.e., the inner peripheral surface 31e) along a direction intersecting (e.g., orthogonal) with the +X direction. The joint surface 31da forms an infinite shape (ring shape) around the center line L1. The internal thread portion 45 opens on the joint surface 31da. The joint surface 31da is an example of the first joint surface.

[0038] In addition, the housing body 31 includes a plurality of body members 41 to 44. The body member 41 includes a part of the cylindrical portion 31a, a part of the end wall portion 31b, and the fixed portion 31c. The body member 42 includes a part of the end wall portion 31b. The body member 43 includes a part of the cylindrical portion 31a. The body member 44 includes a part of the cylindrical portion 31a.

[0039] As Figure 3 and Figure 5 shown, the cover 32 includes a base portion 32a and a mounting portion 32b.

[0040] The base portion 32a has a disk shape extending in a direction intersecting (e.g., orthogonal) with the X direction. The base portion 32a has a joint surface 32da. The joint surface 32da faces the -X direction. The joint surface 32da forms an infinite shape (ring shape) around the center line L1. The joint surface 32da faces the joint surface 31da of the housing body 31. The joint surface 32da is an example of the second joint surface.

[0041] The mounting portion 32b protrudes from the joint surface 32da along the direction opposite to the +X direction (i.e., the -X direction). The mounting portion 32b is mounted in the opening 34. The mounting portion 32b is also referred to as a protrusion.

[0042] The mounting portion 32b has a joint surface 32db. The joint surface 31db is included on the outer peripheral surface of the mounting portion 32b and forms a cylindrical surface shape around the center line L1. The joint surface 32db faces the joint surface 31db of the housing body 31. The joint surface 32da and the joint surface 32db constitute the joint surface 32d.

[0043] In addition, the base portion 32a includes a plurality of through holes 51. The through holes 51 penetrate the joint surface 32da.

[0044] Next, the separation structure of the terminal box 3 will be described.Figure 6 It is a cross-sectional view showing the separation structure 50 in the terminal box 3 of this embodiment.

[0045] As Figure 4 , Figure 5 and Figure 6 shown, the separation structure 50 includes a plurality (e.g., two) of protrusions 37 included in the housing body 31, a plurality (e.g., two) of protrusions 52 included in the cover 32, and an external thread member 61. The protrusion 37 is an example of a first protrusion, and the protrusion 52 is an example of a second protrusion. The external thread member 61 is also referred to as an adjustment bolt.

[0046] As Figure 6 shown, the external thread member 61 is, for example, a bolt. The external thread member 61 has a head 61a and a shaft portion 61b. The shaft portion 61b protrudes from the head 61a. An external thread portion 61c is included on the outer peripheral surface of the shaft portion 61b. The external thread member 61 can be removed during the operation of the rotating electric machine 1.

[0047] The protrusion 37 protrudes from the outer surface 31f of the housing body 31. The protrusion 37 has a surface 37a facing the +X direction. The surface 37a includes a screw receiving portion 37aa. The screw receiving portion 37aa receives the end 61d (the end 61d of the shaft portion 61b) of the external thread member 61. In other words, the end 61d of the external thread member 61 abuts against the screw receiving portion 37aa. The screw receiving portion 37aa is also referred to as an adjustment bolt seat.

[0048] The two protrusions 37 are located outside the joint surface of the joint surface 31da and are aligned with the joint surface 31da therebetween along the line of sight in the +X direction. As a result, the screw receiving portion 37aa is located outside the joint surface of the joint surface 31da and is aligned with the joint surface 31da therebetween.

[0049] The protrusion 52 protrudes from the outer surface 32f of the cover 32m. The protrusion 52 is located on the +X direction side of the protrusion 37.

[0050] The protrusion 52 includes an internal thread portion 53. The internal thread portion 53 is located on the +X direction side of the screw receiving portion 37aa. The internal thread portion 53 is coupled to the external thread portion 61c of the external thread member 61. The external thread portion 61c converts the rotational movement of the external thread member 61 in one rotational direction into a linear movement of the cover 32 relative to the housing body 31 in the +X direction.

[0051] The plurality of protrusions 52 are located outside the joint surface 32da along the line of sight in the +X direction and are aligned with the joint surface 32da therebetween. As a result, the plurality of internal thread portions 53 are located outside the joint surface 32da and are aligned with the joint surface 32da therebetween along the line of sight in the +X direction.

[0052] In the above structure, in order to remove the cover 32 from the housing main body 31, an operator connects the external thread member 61 to the internal thread portion 53 and rotates and tightens the external thread member 61 in one rotational direction. When the external thread member 61 moves in the -X direction while rotating and the end 61d abuts against the screw receiving portion 37aa, the movement of the external thread member 61 in the -X direction stops, and the rotational movement of the external thread portion 61c in one rotational direction is converted into a linear movement of the cover 32 relative to the housing main body 31 in the +X direction through the internal thread portion 53. Therefore, even when the cover 32 is firmly attached to the housing main body 31, the cover 32 can be relatively easily removed from the housing main body 31.

[0053] Even if an explosion occurs in the housing 4 (housing 11 and 21), the rotary electric machine 1 as an explosion-proof electric machine can suppress the sparks from reaching the outside of the housing 11. The following description will illustrate the case where an explosion occurs in the terminal box 3. It should be noted that the rotary electric machine 1 has various structures capable of suppressing an explosion occurring in the housing 4.

[0054] As Figure 3 shown, gaps G1 and G2 can be provided between the housing main body 31 and the cover 32. The gap G1 is provided between the joint surface 31da and the joint surface 32da. The gap G2 is provided between the joint surface 31db and the joint surface 32db.

[0055] When an explosion occurs inside the housing 21, the sparks may enter the gaps G1 and G2. However, the sparks lose pressure when passing through the gaps G1 and G2. In addition, the sparks collide with the housing 21 at the portion where the gap G1 and the gap G2 are connected, resulting in a pressure drop. Therefore, the rotary electric machine 1 can eliminate the sparks in the gap G2.

[0056] Meanwhile, in the present embodiment, since the external thread portion 61c is provided outside the joint surface 32db, the shortening of the joint surface 32db is suppressed. Therefore, the pressure resistance and explosion-proof performance are further improved.

[0057] As described above, in the present embodiment, the rotary electric machine 1 includes a housing 21, a screw receiving portion 37aa, and an internal thread portion 53. The housing 21 includes a housing main body 31 (first member) and a cover 32 (second member). The housing main body 31 includes an opening 34. The cover 32 is mounted in the opening 34 to close the opening 34, and is removed from the housing main body 31 (first member) by moving in the +X direction (first direction) relative to the housing main body 31. The screw receiving portion 37aa is included in the housing main body 31 and receives the end 61d of an external thread member 61. The internal thread portion 53 is included in the cover 32, is located on the +X direction side of the screw receiving portion 37aa, is coupled to the external thread member 61, and converts the rotational movement of the external thread member 60 in one rotational direction into a linear movement of the cover 32 relative to the housing main body 31 in the +X direction. The housing main body 31 has an inner peripheral surface 31e forming the opening 34 and a joint surface 31da (first joint surface), the joint surface 31da being annular and protruding from the inner peripheral surface 31e in a direction intersecting the +X direction. The cover 32 has a joint surface 32da (second joint surface) and a mounting portion 32b, the joint surface 32da being annular and facing the joint surface 31da, the mounting portion 32b protruding from the joint surface 32da in a direction opposite to the +X direction and being mounted in the opening 34. The screw receiving portion 37aa is located outside the joint surface 31da in the line of sight along the +X direction. The internal thread portion 53 is located outside the joint surface 32da in the line of sight along the +X direction.

[0058] According to such a structure, the rotary electric machine 1 of the present embodiment can further improve the withstand voltage and explosion-proof properties.

[0059] Furthermore, the screw receiving portion 37aa is aligned with the joint surface 31da interposed therebetween in the line of sight along the +X direction. The internal thread portion 53 is aligned with the joint surface 32da interposed therebetween in the line of sight along the +X direction.

[0060] According to this structure, it is possible to remove the cover 32 more easily.

[0061] Although some embodiments of the present invention have been described above, the above embodiments are merely examples and are not intended to limit the scope of protection of the present invention. These above embodiments can be implemented in various other forms, and various omissions, substitutions, or modifications can be made without departing from the gist of the present invention. In addition, specifications such as components or shapes (structure, type, direction, shape, size, length, width, thickness, height, number of items, arrangement, position, material, or others) can be appropriately modified according to the implementation situation.

Claims

1. A rotating electric machine, comprising: A housing, including a first member and a second member, the first member including an opening, the second member being installed in the opening to close the opening and being removable from the first member by moving in a first direction relative to the first member; A screw receiving portion, receiving an end of an externally threaded member and included in the first member; And An internal thread portion, included in the second member, located in the first direction relative to the screw receiving portion, coupled to the externally threaded member, and converting a rotational movement of the externally threaded member in one rotational direction into a linear movement of the second member relative to the first member in the first direction, Wherein, The first member includes: An inner peripheral surface, forming the opening; and A first engagement surface, protruding from the inner peripheral surface in a direction intersecting the first direction and being annular, The second member includes: A second engagement surface, facing the first engagement surface and being annular; and A mounting portion, protruding from the second engagement surface in a direction opposite to the first direction and being installed in the opening, The screw receiving portion is located outside the first engagement surface in a line of sight along the first direction, and The internal thread portion is located outside the second engagement surface in a line of sight along the first direction.

2. The rotating electric machine according to claim 1, wherein, The screw receiving portion includes a screw receiving portion aligned with the first engagement surface interposed therebetween in the line of sight in the first direction, and The internal thread portion includes an internal thread portion aligned with the second engagement surface interposed therebetween in the line of sight in the first direction.

3. The rotating electric machine according to claim 1, further comprising: A first protrusion, protruding from the first member; And A second protrusion, protruding from the second member, Wherein, The screw receiving portion is included in the first protrusion, The internal thread portion is included in the second protrusion.

4. The rotating electric machine according to any one of claims 1 to 3, further comprising: A terminal box having the housing.

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