JP2013258913A - Electric motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric motor capable of easily conducting the maintenance work and achieving the weight reduction.SOLUTION: The electric motor includes: a stator core 11; first and second frames 16, 18, 22 fixed to both sides of the stator core; a first bearing housing 40 which holds a bearing and is detachably attached to the first frame from the motor exterior side; a second bearing housing 52 which holds a bearing and is detachably attached to the second frame from the motor exterior side; a rotor including a rotation shaft 27 rotatably supported by the bearing and a rotor core 26 attached to the rotation shaft; and a support structure part which supports the rotor relative to the first and second frames when the first and second bearing housings are removed. The second frame includes a first protruding part 74a fitting with a stator core side engagement groove 76a and a second protruding part 74b fitting with an engagement groove 76b provided at the second bearing housing.

Description

  Embodiments described herein relate generally to a vehicular electric motor that drives a railway vehicle.

  Generally, in a railway vehicle (hereinafter referred to as a vehicle), a main motor (hereinafter referred to as an “electric motor”) is loaded on a carriage disposed under the vehicle body, and the rotational force of the electric motor is transmitted via a joint and a gear device. The vehicle is traveling by transmitting to the wheels.

  There is an increasing need for an electric motor having an extended maintenance cycle, that is, a high maintenance efficiency. In order to satisfy such needs, the development of fully-enclosed motors is underway.

  This electric motor includes a stator iron core having a stator coil provided on the inner peripheral side of a cylindrical frame, and a bracket and a housing that are attached to both ends of the frame and constitute a sealed case. Built-in bearing. A rotor shaft extends in the sealed case, and both end portions thereof are rotatably supported by bearings. A rotor core is attached to the center of the rotor shaft and is located inside the stator core. Moreover, a partition plate is attached to both ends of the rotor shaft within the sealed case, and a labyrinth seal portion is formed between the outer peripheral portion of each partition plate and the bracket.

  In recent years, in order to suppress the heat generation of the rotor and realize a more compact electric motor, a permanent magnet type electric motor configured by inserting a permanent magnet into a rotor core instead of a squirrel-cage rotor is increasing.

  In the electric motor configured as described above, since the outside air does not circulate through the inside of the apparatus, the inside of the apparatus is not contaminated with dust, and it is possible to save labor by eliminating the disassembly of the electric motor for internal cleaning. However, since the bearing is slid by the grease filled in the bearing portion, the slidable grease deteriorates during operation, and the slidable grease needs to be renewed. The oil lubrication grease needs to be renewed after disassembling the motor, which requires a lot of labor and time.

  Therefore, in order to improve the maintenance of the bearing portion, a fully-closed electric motor that can disassemble, clean, and maintain the bearing portion without removing the rotor from the stator has been proposed.

JP 2008-029150 A JP 2008-099491 A

  On the other hand, there is a great need for weight reduction of electric motors in order to improve the performance of railway vehicles, and various weight reduction measures have been adopted. As one of the effective weight reduction measures, it can be considered that a part of the iron frame is constituted by a lightweight aluminum bracket or the like. However, since aluminum has a larger amount of thermal expansion than iron, a gap due to a difference in thermal expansion occurs in the fitting portion between iron and aluminum. As a result, the axis of the rotor changes (shifts), which affects the smooth driving force of the rotor.

  An object of the present invention is to provide an electric motor that can easily perform maintenance work and can be reduced in weight.

  According to the embodiment, the electric motor holds the cylindrical stator iron core, the first frame frame and the second frame frame fixed on both sides of the stator iron core in the axial direction, the bearing, and the first frame frame. A first bearing housing that is detachably attached from the outside of the machine, a second bearing housing that holds the bearing and is detachably attached to the second frame frame from the outside of the machine, and is rotatably supported by the two bearings The rotor having a rotor core attached to the rotary shaft and facing the stator iron core, and the first and second frame frames when removing the first and second bearing housings. A support structure that supports the rotor, and the second frame is provided on the second bearing housing and a first protrusion that fits into an engagement groove on the stator core side. It has a second projection that fits into the engagement groove, the.

FIG. 1 is a cross-sectional view illustrating an electric motor according to a first embodiment. FIG. 2 is an enlarged cross-sectional view around the first bearing portion of the electric motor. FIG. 3 is a cross-sectional view of the electric motor showing the first bearing portion in a state where the rotor is locked by a lock member. FIG. 4 is a cross-sectional view of the electric motor showing a state in which the first bearing portion and the second bearing portion of the electric motor are disassembled. FIG. 5 is a cross-sectional view of the electric motor showing an assembly process of the electric motor. FIG. 6 is a cross-sectional view showing a part of the electric motor according to the second embodiment. FIG. 7 is a cross-sectional view showing a part of the electric motor according to the third embodiment. FIG. 8 is a cross-sectional view showing a part of an electric motor according to a fourth embodiment. FIG. 9 is a cross-sectional view showing a part of an electric motor according to a fifth embodiment.

  Various embodiments will be described below with reference to the drawings. In addition, the same code | symbol shall be attached | subjected to a common structure through embodiment, and the overlapping description is abbreviate | omitted. In addition, each drawing is a schematic diagram for promoting the embodiment and its understanding, and its shape, dimensions, ratio, etc. are different from the actual device, but these are considered in consideration of the following description and known techniques. The design can be changed as appropriate.

(First embodiment)
FIG. 1 shows a fully-closed electric motor according to the first embodiment. This electric motor includes a cylindrical stator iron core 11, and a pair of annular iron core holders 12 a and 12 b are fixed to both axial end surfaces of the stator iron core 11. A plurality of connecting plates 14 are disposed on the outer periphery of the stator core 11. Each of these connecting plates 14 extends in the axial direction of the stator iron core 11, and both ends thereof are fixed to the iron core retainers 12a and 12b. The plurality of connecting plates 14 are arranged at intervals in the circumferential direction of the stator core 11.

  A substantially cylindrical first bracket 16 made of an aluminum alloy or the like is attached to the iron core retainer 12a located on the drive end side of the stator iron core 11. An annular bearing bracket 18 is coaxially fastened to the front end side of the first bracket 16 with a bolt. A first bearing portion 20 containing a bearing to be described later is fastened to the center portion of the bearing bracket 18 with a bolt. The first bracket 16 and the bearing bracket 18 constitute a first frame frame of the electric motor.

  A substantially bowl-shaped second bracket 22 formed of an aluminum alloy or the like is attached to the iron core retainer 12b located on the counter driving end side of the stator iron core 11. A second bearing portion 24 containing a bearing to be described later is fastened to the center portion of the second bracket 22 with a bolt. The second bracket 22 constitutes a second frame frame of the electric motor.

  The stator core 11, the core retainers 12a and 12b, the first bracket 16, the bearing bracket 18, the second bracket 22, and the first and second bearing portions 20 and 24 form a case (airframe) whose interior is sealed. ing.

  In the electric motor, members other than the first bracket 18 and the second bracket 22 include various members to be described later, and the majority are made of iron. As described above, the first bracket 18 and the second bracket 22 are formed of a material different from other members, that is, a material different from iron. In the present embodiment, in order to reduce the weight of the electric motor, the first bracket 18 and the second bracket 22 are made of a material that is lighter than iron or has a lower specific gravity than iron, such as aluminum or an aluminum alloy. . As long as the material is lighter than iron or has a specific gravity smaller than iron, other materials may be used instead of aluminum.

  The stator iron core 11 is configured by laminating a large number of annular metal plates made of a magnetic material, for example, a silicon steel plate. A plurality of slots extending in the axial direction are formed in the inner peripheral portion of the stator core 11, and the stator coil 23 is embedded in these slots. The coil ends of the stator coil 23 protrude in the axial direction from both end surfaces of the stator core 11. The stator core 11 and the stator coil 23 constitute a stator (stator).

  A cylindrical rotor core 26 is coaxially disposed inside the stator core 11 with a gap therebetween. A rotary shaft 27 is coaxially attached to the central portion of the rotor core 26, and both end portions thereof are rotatably supported by the first bearing portion 20 and the second bearing portion 24. Thereby, the rotating shaft 27 extends coaxially in the case. The rotating shaft 27 and the rotor core 26 constitute a rotor (rotor). The drive side end 27a of the rotary shaft 27 extends outside the machine, and a joint for connecting the drive gear device is attached to this portion.

  The rotor core 26 is configured by laminating a large number of annular metal plates made of a magnetic material, for example, a silicon steel plate. The rotor iron core 26 is supported by a pair of iron core pressers 28a and 28b attached to the rotary shaft 27 so as to be sandwiched from both side surfaces in the axial direction. The iron core pressing plates 28 a and 28 b are formed in an annular shape, and the outer diameter thereof is slightly smaller than the outer diameter of the rotor iron core 26.

  A plurality of grooves extending in the axial direction are formed on the outer peripheral portion of the rotor core 26, and a rotor bar 31 is embedded in each groove. Both end portions of the rotor bar 31 are extended from the rotor iron core 26, and the extended portions are integrally connected by an end ring 25 to form a squirrel-cage rotor of an induction motor. By energizing the stator coil 23, the rotor iron core 26 is guided and rotated, and the rotating shaft 27 is rotated integrally with the rotor iron core 26.

  In addition, in order to suppress the heat generation of the rotor and realize a more compact electric motor, a permanent magnet type electric motor configured by inserting a permanent magnet into the rotor core may be used instead of the cage rotor.

  A first partition plate 30 is coaxially attached to the rotary shaft 27 between the first bearing portion 20 on the drive end side and the rotor core 26, and is rotatable integrally with the rotary shaft 27. The first partition plate 30 is formed in a substantially funnel shape, and extends obliquely from the rotor core 26 side toward the first bracket 16. The outer periphery of the first partition plate 30 and the inner periphery of the overhanging portion of the bearing bracket 18 are engaged with each other with an annular minute gap. The annular minute gaps are formed in a substantially two-stage structure having an uneven shape to form a labyrinth structure X. In the first partition plate 30, a plurality of fins are formed on the outer surface facing the first bearing portion 20.

  A second partition plate 32 is coaxially attached to the iron core retainer 28 b between the second bearing portion 24 on the counter-drive end side and the rotor iron core 26, and is rotatable integrally with the rotary shaft 27. The second partition plate 32 is formed in a substantially funnel shape and extends inclined from the rotor core 26 side toward the second bracket 22. The outer peripheral edge of the second partition plate 32 and the inner peripheral portion of the overhanging portion of the second bracket 22 are engaged with each other with an annular minute gap. The annular minute gaps are formed in a substantially two-stage structure having an uneven shape, and form a labyrinth structure Y. In the second partition plate 32, a plurality of fins are formed on the outer surface facing the second bearing portion 24.

  The first partition plate 30 and the second partition plate 32 have a function of secretly blocking the machine interior space where the stator iron core 11 and the rotor iron core 26 are located and the outside of the machine and radiating heat generated by the rotor. Yes.

  The first bearing portion 20 is provided with a space 34 outside the first partition plate 30. This space 34 constitutes a heat insulating structure in which heat generated by the stator coil 23 and the rotor does not affect the first bearing portion 20. In addition, outside air inlet holes (not shown) communicating with the space 34 are formed in the bearing bracket 18 and a first bearing housing 40 described later so that outside air can be introduced into the space 34, and the bearing bracket 18 has a space 34 in the space 34. A plurality of discharge holes 36 are formed. By rotating the first partition plate 30, outside air is introduced into the space 34 from the outside air inlet hole, and after cooling the inside of the space 34, the outside air is discharged to the outside through the discharge hole 36. Thereby, it contributes to cooling of the 1st bearing part 20 and a rotor.

  A second bearing portion 24 is provided with a space 37 outside the second partition plate 32. The space 37 constitutes a heat insulating structure in which heat generated by the stator coil 23 and the rotor does not affect the second bearing portion 24. An outside air inlet (not shown) communicating with the space 37 is formed in the second bracket 22 and a second bearing housing 52 described later so that outside air can be introduced into the space 37, and the second bracket 22 leads to the space 37. A plurality of discharge holes 38 are formed. By rotating the second partition plate 32, outside air is introduced into the space 34 from the outside air inlet hole, and after cooling the inside of the space 37, it is discharged to the outside through the discharge hole 38. This contributes to cooling of the second bearing portion 24 and the rotor.

Next, the first bearing portion 20 and the second bearing portion 24 will be described in detail.
In the first bearing portion 20, an opening is formed in the central portion of the bearing bracket 18, and the first bearing housing 40 is fitted into the opening from the outside. The flange portion 40 a of the first bearing housing 40 is bolted to the outer surface of the bearing bracket 18 from the outside with a plurality of bolts 41, whereby the first bearing housing 40 is fixed to the bracket 18. A roller bearing 42 is built in the first bearing housing 40. An inner ring of the roller bearing 42 is fitted to the rotary shaft 27. An end lid 44 is fixed to the first bearing housing 40 with bolts 43 from the outside so as to cover the opening of the first bearing housing 40. In the first bearing housing 40, oil lubrication grease is filled around the roller bearing 42.

  As shown in FIGS. 1 and 2, an annular first lock member 44 a is provided on the outer peripheral side of the first bearing housing 40 and is located on the inner surface side of the bearing bracket 18. The outer periphery of the first lock member 44a is slidably engaged with an annular convex portion 18a protruding from the inner surface side of the bearing bracket 18. The first lock member 44 a can slide on the bearing bracket 18 along the axial direction of the rotary shaft 27. The first lock member 44 a integrally has a funnel-shaped contact portion 45 extending toward the rotation shaft 27. During normal operation of the electric motor, the first lock member 44a is fixed to the illustrated fixed position, that is, the position in contact with the inner surface of the bearing bracket by a plurality of fixing bolts 46 screwed from the outside of the bearing bracket 18. The plurality of fixing bolts 46 are provided on a circle concentric with the rotating shaft 27 at a predetermined interval in the circumferential direction. The fixing bolts 46 are provided at positions symmetrical with respect to the rotating shaft 27. Each fixing bolt 46 is inserted from the outside through a through hole formed in the bearing bracket 18 and screwed into a screw hole formed in the first lock member 44a.

  An annular receiving seat 48 is coaxially fixed to the rotary shaft 27 in the vicinity of the first bearing housing 40. The receiving seat 48 as a receiving member has a tapered surface formed on the outer periphery thereof. The tapered surface is continuously formed over the entire circumference and is positioned concentrically with the rotating shaft 27. The tapered surface faces the contact portion 45 of the first lock member 44a with a slight gap.

  As shown in FIG. 1, in the second bearing portion 24, an opening is formed in the center portion of the second bracket 22, and the second bearing housing 52 is fitted into the opening from the outside. The flange portion 52 a of the second bearing housing 52 is bolted to the outer surface of the second bracket 22 from the outside with a plurality of bolts 53, whereby the second bearing housing 52 is fixed to the second bracket 22. A ball bearing 54 is built in the second bearing housing 52. The inner ring of the ball bearing 54 is fitted to the rotary shaft 27. An end lid 56 is fixed to the second bearing housing 52 with bolts 57 from the outside so as to cover the opening of the second bearing housing 52. In the second bearing housing 52, oil lubrication grease is filled around the ball bearing 54. Further, an end plate 58 is bolted to the non-output side end of the rotating shaft 27, and the end plate restricts the ball bearing 54 from coming off.

  An annular second lock member 44 b is fitted to the outer periphery of the second bearing housing 52 and is located on the inner surface side of the second bracket 22. The outer periphery of the second lock member 44 b is slidably fitted to the inner peripheral surface of the opening formed in the center of the second bracket 22, and the inner periphery of the second lock member 44 b is the outer peripheral surface of the second bearing housing 52. It is slidably fitted to. The second lock member 44 b can slide on the second bearing housing 52 along the axial direction of the rotary shaft 27. The second lock member 44 b integrally has a funnel-shaped contact portion 45 extending toward the rotation shaft 27. During normal operation of the electric motor, the second lock member 44b is fixed to the illustrated fixed position, that is, the position in contact with the inner surface of the second bracket by a plurality of fixing bolts 60 screwed from the outside of the second bracket 22. . The plurality of fixing bolts 60 are provided on a circle concentric with the rotating shaft 27 at predetermined intervals in the circumferential direction. Further, the fixing bolt 60 is provided at a position symmetrical with respect to the rotation shaft 27. Each fixing bolt 60 is inserted from the outside through a through hole formed in the second bracket 22 and screwed into a screw hole formed in the second lock member 44b.

  An annular receiving seat 62 is coaxially fixed to the rotary shaft 27 in the vicinity of the second bearing housing 52. The receiving seat 62 as a receiving member has a tapered surface formed on the outer periphery thereof. The tapered surface is continuously formed over the entire circumference and is positioned concentrically with the rotating shaft 27. The tapered surface faces the contact portion 45 of the second lock member 44b with a slight gap.

  The first and second lock members 44a and 44b and the receiving seats 48 and 62 described above are configured so that the rotor can be attached to the first and second frames when the first and second bearing housings 40 and 52 and the bearings 42 and 54 are removed. The support structure part fixedly supported with respect to a frame is comprised.

  According to the fully closed type electric motor configured as described above, the heat generated by the stator coil 23 is radiated to the outside air via the outer peripheral surface of the stator core 11 and the first and second brackets 16 and 22, and the heat generated by the rotor. Radiates heat at the first and second partition plates 30 and 32. The first and second bearing portions 20 and 24 are separated from the stator coil 23 and the like of the heating source by spaces 34 and 37 defined by the first and second partition plates 30 and 32, and are introduced into these spaces. Cooled by outside air. For this reason, the structure is such that the influence of heat is reduced and full closure can be realized. The fully closed motor thus improved does not require the introduction of outside air into the machine, so that it is not necessary to clean the filter and the machine, and the maintenance can be significantly reduced.

  Further, with the above-described configuration of the bearing portion, the bearing portion can be disassembled, cleaned, and maintained without removing the rotor from the stator. That is, by removing the fixing bolts 46, 60 that fix the first and second lock members 44a, 44b, and screwing a plurality of push bolts instead, the first and second lock members 44a, 44b The rotor moves to the center side along the central axis, hits the tapered surfaces of the receiving seats 48 and 62 attached to the rotary shaft 27, and the rotor can be fixedly held to the stator.

  Such a locking mechanism will be described in more detail. As shown in FIGS. 1 and 2, during normal operation of the electric motor, the first and second lock members 44 a and 44 b are attracted to the bearing bracket 18 and the second bracket 22 by the fixing bolts 46 and 60, and the receiving seat 48. , 62 away from each other. Thereby, the rotor can be rotated.

  On the other hand, at the time of maintenance and inspection, for example, as shown in FIG. 3, the first locking member 44 a moves to the center side along the central axis of the motor by removing the fixing bolt 46 and screwing the push bolt 50 instead. Then, the contact portion 45 contacts the tapered surface of the receiving seat 48. The second lock member 44b is also pushed into the center side of the electric motor by the push bolt, and the contact portion 45 contacts the tapered surface of the receiving seat 62. Thus, the rotor is pressed from opposite directions by the first lock member 44a and the second lock member 44b, and is fixedly held to the stator. That is, the rotor is fixed to the frame frame while being held coaxially with the stator core 11 and with a predetermined gap.

  By fixing the rotor in this manner, the first and second bearing portions 20 and 24 can be disassembled, inspected, refilled with grease, and the like without pulling out the rotor from the stator. That is, as shown in FIG. 4, the first bearing portion 20 and the second bearing portion 24 can be disassembled from the rotor and the frame frame at the bearing housing portion in a state where the rotor is fixed to the stator.

  For example, with respect to the first bearing portion 20, after removing the bolt 41, the first bearing housing 40 is pulled out from the bearing bracket 18, and after removing the bolt 43, the end cover 44 is removed from the first bearing housing 40. . The oil lubrication grease of the bearing outer ring attached to the inner periphery of the first bearing housing 40 is replaced with a new one.

  Further, after removing the bolt 57 from the second bearing portion 24, the end cover 56 is removed from the second bearing housing 52, and the bolt is removed to remove the end plate 58 from the end of the rotary shaft 27. Subsequently, after the bolt 53 is removed, the second bearing housing 52 is extracted from the second bracket 22 to the outside, and the oil lubrication grease of the bearing outer ring attached to the inner periphery of the second bearing housing 52 is replaced with a new one. At this time, the entire rotor including the rotary shaft 27 is fixed and held by the first and second lock members 44a and 44b. Therefore, even if the first bearing housing 40 and the second bearing housing 52 are pulled out, the entire rotor It is held at a predetermined position with respect to the stator.

  After the bearing grease is renewed, the first bearing housing 40 and the second bearing housing 52 are assembled into the bearing bracket 18 and the second bracket 22 and fixed to the bracket with bolts 41 and 53. Next, the end lid 44, the end plate 58, and the end lid 56 are each fixed with bolts. Thereafter, the fixing bolt 46 is screwed into the first lock member 44 a from the outside instead of the push bolt 50, and the first lock member 44 a is returned to the initial position separated from the seat 48. Similarly, the fixing bolt 60 is screwed into the second lock member 44 b from the outside instead of the push bolt 64, and the second lock member 44 b is returned to the initial position separated from the seat 62. As a result, the fixing of the rotor is released and the rotor becomes rotatable, and the renewal of the oil lubrication grease is completed.

  By adopting such a mechanism, it is possible to perform replacement maintenance of the grease and the bearing in the bearing portion without pulling out the rotor from the stator. In particular, in a rotor structure using permanent magnets, there is a permanent magnet with a strong magnetic force in the rotor core, so that the rotor core is attracted to the stator core of the stator when the rotor is pulled out, and the pulling operation becomes very difficult. However, the above configuration can also solve such a problem.

  As shown in FIG. 1, the frame of the electric motor is eliminated, the stator iron core 11 is partially fixed by the connecting plate 14, and the first bracket 16 and the second bracket 22 made of aluminum alloy are axially extended from both ends of the stator iron core 11. It is configured as a frame frame extending to the bearing portion. According to this configuration, a significant weight reduction can be realized by making a part of the iron frame aluminum. In addition, by adopting a double fitting structure for the fitting portion between the first and second brackets 16 and 22 and the iron material, the fitting portion is displaced due to the difference in thermal expansion between the iron and the aluminum alloy, and the gap is reduced. As a result, the shaft center of the rotor can be prevented from changing and the smooth driving of the rotor can be maintained.

  More specifically, as shown in FIG. 1, the first bracket 16 includes an annular first convex portion 70a formed at the end on the stator core 11 side and an annular second convex formed at the end on the bearing bracket side. The protrusion 70b is integrally provided. The first protrusion 70a protrudes toward the stator iron core 11, and the second protrusion 70b protrudes in the opposite direction to the first protrusion, that is, in the direction of the bearing bracket 18. The first convex part 70 a and the second convex part 70 b are formed coaxially with the rotating shaft 27. An annular groove (engagement groove) 72a is formed in the iron core retainer 12a. An annular groove (engagement groove) 72b is formed on the inner surface side of the bearing bracket 18. These annular grooves 72 a and 72 b are formed coaxially with the rotary shaft 27.

  The first convex portion 70a of the first bracket 16 is fitted into the annular groove 72a of the iron core retainer 12a, and the first convex portion 70a is doubly fitted so that the inner peripheral surface and the outer peripheral surface of the first convex portion 70a are sandwiched from both sides by the iron core retainer 12a. Match. Similarly, the second convex portion 70b of the first bracket 16 is fitted into the annular groove 72b of the bearing bracket 18 and is doubled so that the inner peripheral surface and the outer peripheral surface of the second convex portion 70b are sandwiched from both sides by the bearing bracket. Is fitted.

  The second bracket 22 is integrally provided with an annular first convex portion 74a formed at the end on the stator iron core 11 side and an annular second convex portion 74b formed at the opening end on the second bearing housing side. Yes. The 1st convex part 74a protrudes in the stator core 11 side, and the 2nd convex part 74b protrudes in the opposite direction to a 1st convex part, ie, the outer side of a case. The first convex portion 74 a and the second convex portion 74 b are formed coaxially with the rotating shaft 27. An annular groove (engagement groove) 76a is formed in the iron core retainer 12b. An annular groove (engagement groove) 76 b is formed on the inner surface of the flange 52 a of the second bearing housing 52. These annular grooves 76 a and 76 b are formed coaxially with the rotary shaft 27.

  The first convex portion 74a of the second bracket 22 is fitted into the annular groove 76a of the iron core retainer 12b, and the first convex portion 74a is doubly fitted so that the inner peripheral surface and the outer peripheral surface thereof are sandwiched from both sides by the iron core retainer 12b. Match. Similarly, the second convex portion 74 b of the second bracket 22 is fitted in the annular groove 76 b of the second bearing housing 52. The second locking member 44b has an annular convex portion 47 projecting outward, and the convex portion 47 is fitted in the annular groove 76b of the second bearing housing together with the second convex portion 74b of the second bracket 22. Match. Thereby, the outer peripheral surface of the 2nd convex part 74b is fitted to the flange of the 2nd bearing housing 52, and the inner peripheral surface is fitted to the convex part 47 of the 2nd lock member 44b. Thereby, the 2nd convex part 74b is fitted twice so that it may be pinched | interposed from the inner periphery and both sides of an outer periphery. The convex portion 47 of the second lock member 44b has an outer peripheral surface fitted into the inner peripheral surface of the central opening of the second bracket 22 and the inner peripheral surface of the second convex portion 74b, and the inner peripheral surface is a second bearing housing. The outer periphery of 52 is fitted. As a result, the second lock member 44b is positioned and supported so as to be slidable along the axial direction.

  As described above, the fitting portion between the first and second brackets 16 and 22 and the iron material has a double fitting structure, so that the fitting portion is displaced due to the difference in thermal expansion between iron and the aluminum alloy. Generation | occurrence | production of a clearance gap can be prevented and the position shift of a 1st and 2nd bracket can be suppressed. Therefore, the weight of the electric motor can be reduced by using a frame made of an aluminum alloy or the like. Even in such a double-fitting structure, only the bearing portion is maintained without degrading the full-fitting function without maintaining the full-closeness of the full-closed electric motor and without disassembling the whole electric motor. Can be easily removed, disassembled and maintained.

  The assembly of the entire electric motor having the above-described configuration, that is, the case where the rotor is inserted and installed in the case will be described. As shown in FIG. 5, first, the iron core holders 12a and 12b, the first bracket 16, and the second bracket 22 are fixed to the stator iron core 11 to form a case. On the other hand, the iron core retainer, the first partition plate 30, the receiving seat 48, the first lock member 44a, the first bearing housing 40, and the bearing bracket 18 are assembled to the drive side shaft end portion of the rotor. An iron core retainer, a second partition plate 32, a receiving seat 62, and a second lock member 44b are assembled to the shaft end of the rotor on the non-driving side, and a disk-shaped assembly jig 80 is concentric with the driving shaft end. The second locking member 44b is fixed and held on the rotor by the assembly jig 80. The assembly jig 80 is formed to have an outer diameter that can be brought into contact with the convex portion 47 of the second lock member 44 a and can be inserted into the central opening 22 a of the second bracket 22.

  Subsequently, such a rotor is inserted into the case and the stator core 11 through the central opening of the first bracket 16 and positioned at a predetermined position. And the bearing bracket 18 is bolted to the 1st bracket 16, and the drive side axial part of a rotor is supported. Further, the convex portion 47 of the second lock member 44b assembled to the opposite end of the rotor on the opposite side of the rotor is fitted into the central opening 22a of the second bracket 22 and fixed to the second bracket by the fixing bolt 60. Thereby, the counter drive side shaft portion of the rotor is supported by the second bracket 22. At this time, the assembly jig 80 is inserted into the central opening 22a of the second bracket 22 and can be removed from the outside of the second bracket.

  Next, after the assembly jig 80 is removed from the shaft end of the rotor, the ball bearing 54, the second bearing housing 52, the end plate 58, and the end lid 56 are sequentially attached from the outside and fixed with bolts. Thereby, the assembly is completed.

  In order to enable assembly of the electric motor as described above, the second protrusion 74b of the second bracket 22 is formed so as not to interfere with the assembly jig 80 during assembly. That is, the 2nd convex part 74b is formed in the outer side of the center opening 22a of the 2nd bracket 22, and is formed so that it may protrude in the axial direction outward of a case from a 2nd bracket. As a result, the second protrusion 74b does not protrude into the central opening 22a of the second bracket 22, and the assembly jig 80 can be inserted into the central opening 22a of the second bracket 22, and the assembly jig 80 from the outside of the case. Can be removed.

Next, an electric motor according to another embodiment will be described.
In the embodiments described below, the same parts as those in the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted.

(Second Embodiment)
FIG. 6 shows a part of a fully-closed electric motor according to the second embodiment. In the second embodiment, the fitting structure of the second convex portion 74b of the second bracket 22 and the fitting structure of the second lock member 44b are different from the first embodiment.

  The second bracket 22 formed of aluminum alloy or the like is integrally provided with an annular second convex portion 74b formed at the opening end on the second bearing housing side. The 2nd convex part 74b protrudes toward the outer side of a case. The second convex portion 74 b is formed coaxially with the rotation shaft 27. An annular groove 76 b is formed on the inner surface of the flange 52 a of the second bearing housing 52. The annular groove 76 b is formed coaxially with the rotary shaft 27.

  The second convex portion 74b of the second bracket 22 is fitted in the annular groove 76b of the second bearing housing 52, and the inner peripheral surface and the outer peripheral surface of the second convex portion 74b are sandwiched from both sides by the second bearing housing 2. It fits heavily.

  The second lock member 44 b has an annular convex portion 47 protruding outward, and the outer peripheral surface of the convex portion 47 is fitted to the inner peripheral surface of the central opening of the second bracket 22. Thus, the second lock member 44b is positioned and supported so as to be slidable along the axial direction of the rotary shaft 27 with the outer peripheral surface of the convex portion 47 as a guide.

(Third embodiment)
FIG. 7 shows a part of a fully-closed electric motor according to the third embodiment. In the third embodiment, the fitting structure of the second protrusion 74b of the second bracket 22 and the fitting structure of the second lock member 44b are different from those of the first example.

  The second bracket 22 formed of aluminum alloy or the like includes an annular second convex portion 74b formed at the opening end on the second bearing housing side, and an annular third convex portion formed on the outer peripheral side of the opening end. 74c. The 2nd convex part 74b protrudes toward the outer side of a case, and the 3rd convex part 74c protrudes from the inner surface of the 2nd bracket 22 to the rotor iron core 26 side. The second convex portion 74 b and the third convex portion 74 c are formed coaxially with the rotating shaft 27. An annular groove 76 b is formed on the inner surface of the flange 52 a of the second bearing housing 52. The annular groove 76 b is formed coaxially with the rotary shaft 27.

  The second convex portion 74b of the second bracket 22 is fitted in the annular groove 76b of the second bearing housing 52, and the inner peripheral surface and the outer peripheral surface of the second convex portion 74b are sandwiched from both sides by the second bearing housing 2. It fits heavily.

  The second lock member 44b is fixed in contact with the inner surface of the second bracket 22, and the outer peripheral surface is fitted to the inner peripheral surface of the third convex portion 74c. Thus, the second lock member 44b is positioned and supported so as to be slidable along the axial direction of the rotary shaft 27 with the inner peripheral surface of the third convex portion 74c as a guide.

(Fourth embodiment)
FIG. 8 shows a part of a fully-closed electric motor according to the third embodiment. In 4th Embodiment, the fitting structure of the 2nd convex part 74b of the 2nd bracket 22 and the fitting structure of the 2nd lock member 44b are different from 1st Embodiment.

  The second bracket 22 formed of aluminum alloy or the like is integrally provided with an annular second convex portion 74b formed at the opening end on the second bearing housing side. The 2nd convex part 74b protrudes toward the outer side of a case. The second convex portion 74 b is formed coaxially with the rotation shaft 27. An annular groove 76 b is formed on the inner surface of the flange 52 a of the second bearing housing 52. The annular groove 76 b is formed coaxially with the rotary shaft 27.

  The second convex portion 74b of the second bracket 22 is fitted in the annular groove 76b of the second bearing housing 52, and the inner peripheral surface and the outer peripheral surface of the second convex portion 74b are sandwiched from both sides by the second bearing housing 2. It fits heavily.

  The second lock member 44b has an annular protrusion 47 protruding outward. The second lock member 44b is in contact with the inner surface of the second bracket 22, the outer peripheral surface of the convex portion 47 is fitted to the inner peripheral surface of the central opening of the second bracket 22, and the inner peripheral surface of the convex portion 47 is The outer peripheral surface of the second bearing housing 52 is fitted. Accordingly, the second lock member 44b is positioned and supported so as to be slidable along the axial direction of the rotary shaft 27 with the second bracket 22 and the second bearing housing 52 as guides.

(Fifth embodiment)
FIG. 9 shows a part of a fully-closed electric motor according to the fifth embodiment. In the fifth embodiment, the fitting structure of the second convex portion 74b of the second bracket 22 and the fitting structure of the second lock member 44b are different from those of the first embodiment.

  The second bracket 22 formed of aluminum alloy or the like is integrally provided with an annular second convex portion 74b formed at the opening end on the second bearing housing side. The 2nd convex part 74b protrudes toward the outer side of a case. The second convex portion 74 b is formed coaxially with the rotation shaft 27. An annular groove 76 b is formed on the inner surface of the flange 52 a of the second bearing housing 52. The annular groove 76 b is formed coaxially with the rotary shaft 27. The second convex portion 74b of the second bracket 22 is fitted into the annular groove 76b of the second bearing housing 52, and the outer peripheral surface of the second convex portion 74b is in contact with the second bearing housing.

  The second lock member 44b has an annular protrusion 47 protruding outward. The second lock member 44b is in contact with the inner surface of the second bracket 22, the outer peripheral surface of the convex portion 47 is fitted to the inner peripheral surface of the central opening of the second bracket 22, and the inner peripheral surface of the convex portion 47 is The outer peripheral surface of the second bearing housing 52 is fitted. Accordingly, the second lock member 44b is positioned and supported so as to be slidable along the axial direction of the rotary shaft 27 with the second bracket 22 and the second bearing housing 52 as guides.

  The second bracket 22 has an outer peripheral surface of the second convex portion 74b fitted into the second bearing housing 52, and an inner peripheral surface of the central opening is fitted with an outer peripheral surface of the convex portion 47 of the second lock member 44b. , It is fitted twice so as to be sandwiched from both sides.

  Also in the second to fifth embodiments configured as described above, the same effect as that of the first embodiment can be obtained, the maintenance work can be easily performed, and the weight can be reduced. Can be provided.

Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.
For example, in the above-described embodiment, the first and second bearing portions are a combination of a roller bearing and a ball bearing. However, the present invention is not limited to this, and may be a combination of a flanged roller bearing and a bearing. The electric motor may be an induction motor or a permanent magnet synchronous motor. Each of the first and second partition plates has a fin and functions as a fan. However, the fin may be omitted. The receiving seat for receiving the lock member is not limited to the rotating shaft, and may be provided on the iron core presser or the partition plate.

  The space defined between the first partition plate and the first bearing housing and the space defined between the second partition plate and the second bearing housing are both configured to communicate with the outside air. However, the present invention is not limited to this, and a configuration may be employed in which outside air is blown from one of the spaces through the rotor to the other space, or both spaces may not be communicated with the outside air.

  In addition, instead of the fixing bolt for fixing the lock member, the lock bolt for pushing out the lock member is screwed in, but the structure may be such that both the fixing bolt and the push bolt can be mounted simultaneously. For example, a through hole through which a fixing bolt is inserted and a screw hole into which a push bolt is screwed may be provided side by side on a bracket constituting the frame frame. In this case, a plurality of through holes for fixing bolts and screw holes for push bolts are formed at predetermined intervals in the circumferential direction concentric with the rotating shaft. The fixing bolt is inserted through the through hole of the bracket and screwed into the screw hole formed in the lock member. The push bolt is screwed into the screw hole of the bracket, and the bolt tip is brought into contact with the end face of the lock member, thereby pushing the lock member toward the lock position.

  The tapered surface of the receiving seat with which the lock member abuts is not limited to the case where it extends continuously over the entire circumference, but may be formed intermittently in the circumferential direction. Further, the portion of the receiving seat that contacts the lock member is not limited to a surface, and may be a point, a straight line, or a curved line.

  The present invention is not limited to an electromagnetic induction motor, and may be applied to a magnet motor. The number of fixing screw holes and bolts is not limited to the embodiment, and can be increased or decreased as necessary.

Hereinafter, the invention described in the scope of claims of the present application will be appended.
(Appendix 1)
A cylindrical stator iron core, a first frame frame and a second frame frame fixed to both sides of the stator core in the axial direction, and a first bearing that holds the bearing and is fixed to the first frame frame from the outside of the machine A housing, a second bearing housing that holds the bearing and is fixed to the second frame frame from the outside of the machine, and a rotation that is rotatably supported by the two bearings and extends into the first and second frame frames. And a rotor having a rotor iron core attached to the rotating shaft and facing the stator iron core with a gap therebetween, and a first receiving seat and a second receiving seat respectively provided on the rotor on both sides of the rotor iron core The first frame frame is provided so as to be movable along the axial direction of the rotating shaft, and abuts against the first receiving seat when the rotor is moved to the rotor core side to fix the rotor. A lock member, and a portion including a double fitting portion provided between the second frame and the second bearing housing, provided to be movable along the axial direction of the rotary shaft, and on the rotor core side And a second lock member that contacts the second receiving seat and fixes the rotor when moved.
(Appendix 2)
A first partition plate fixed to the rotor between the rotor core and the first bearing portion and rotatable integrally with the rotating shaft, an outer peripheral edge of the first partition plate, and an inner surface of the first frame frame A labyrinth structure part formed by an annular minute gap therebetween, a second partition plate fixed to the rotor between the rotor core and the second bearing part, and rotatable integrally with the rotary shaft, The electric motor according to appendix 1, further comprising: a labyrinth structure portion formed by an annular minute gap between an outer peripheral edge of the two partition plates and the inner surface of the second frame frame.
(Appendix 3)
The second frame has a second bracket formed of a metal material different from other members, and the second bracket includes an annular first convex portion that is double-fitted to the stator core side, An annular second convex portion fitted in a groove formed in the second bearing housing, and the second convex portion has an outer peripheral surface fitted to the second bearing housing, and the second bearing housing or The electric motor according to claim 2, further comprising an inner peripheral surface that is fitted to at least one of the second lock members.

(Appendix 4)
The second lock member has an annular convex portion fitted between the inner peripheral surface of the second bracket and the second bearing housing, and the inner peripheral surface of the second bracket and the second bearing. The electric motor according to appendix 3, provided to be slidable along the housing.
(Appendix 5)
The second lock member has an annular convex portion fitted to the inner peripheral surface of the second bracket, and is provided to be slidable along the inner peripheral surface of the second bracket. The electric motor described.
(Appendix 6)
The electric motor according to supplementary note 2, wherein a space surrounded by the stator iron core, the first frame frame, the second frame frame, the first partition plate, the second partition plate, and the rotor iron core is substantially blocked from outside air.
(Appendix 7)
The first receiving seat has a tapered surface that can come into contact with the first locking member, and the second receiving seat has a tapered surface that can come into contact with the second locking member. 6. The electric motor according to any one of 6.

11 ... Stator iron core, 12a, 12b ... Iron core retainer, 16 ... First bracket,
18 ... Bearing bracket, 20 ... First bearing portion, 22 ... Second bracket,
24 ... 2nd bearing part, 26 ... Rotor core, 27 ... Rotating shaft, 30 ... 1st partition plate,
32 ... 2nd partition plate, 40 ... 1st bearing housing, 44a ... 1st locking member,
44b ... 2nd lock member, 48, 62 ... receiving seat, 52 ... 2nd bearing housing,
70a, 74a ... 1st convex part, 70b, 74b ... 2nd convex part, 72b, 76b ... annular groove 80 ... assembly jig

Claims (4)

A cylindrical stator core;
A first frame frame and a second frame frame fixed on both axial sides of the stator core;
A first bearing housing that holds the bearing and is detachably attached to the first frame from the outside of the machine;
A second bearing housing that holds the bearing and is detachably attached to the second frame frame from the outside of the machine;
A rotor having a rotating shaft rotatably supported by the two bearings, and a rotor core attached to the rotating shaft and facing the stator core;
A support structure for supporting the rotor with respect to the first and second frame frames when removing the first and second bearing housings;
The second frame frame has a first convex portion that fits into an engaging groove on the stator core side, and a second convex portion that fits into an engaging groove provided in the second bearing housing. .   The second frame frame includes a bracket formed of a metal material including aluminum, and the bracket includes an annular first convex portion that fits twice in an engagement groove on the stator core side, and the second The electric motor according to claim 1, further comprising: an annular second convex portion that fits into the engagement groove of the bearing housing. The first frame frame includes a first bracket formed of a metal material including aluminum, and a bearing bracket attached to the first bracket, and the first bearing housing is attached to the bearing bracket,
The first bracket includes: an annular first convex portion that fits twice in the engaging groove on the stator core side; and an annular second convex portion that fits twice in the engagement groove on the bearing bracket. The electric motor according to claim 1 or 2.   The support structure is provided on a first receiving member and a second receiving member provided on the rotor on both sides of the rotor core, and on the first frame frame so as to be movable along the axial direction of the rotating shaft. The first lock member that contacts the first receiving member when the rotor core is moved to fix the rotor and the second frame frame are movable along the axial direction of the rotating shaft. And a second locking member that contacts the second receiving member and fixes the rotor when moved to the rotor iron core side.