JP7415568B2 - Bearing replacement method, bearing structure, and vehicle traction motor - Google Patents

Description

The present invention relates to a bearing replacement method for a fully enclosed vehicle traction motor that drives a railway vehicle, a bearing structure for a vehicle traction motor, and a vehicular traction motor equipped with this bearing structure.

In a railway vehicle, a fully-enclosed main electric motor that drives the wheels is attached to a bogie placed under the floor of the vehicle body.
For example, the vehicle main electric motor of Patent Document 1 includes a stator core fixed to the inner circumferential side of a substantially cylindrical frame, a rotor core fixed to the rotor shaft inside the stator core, and a rotor core fixed to the rotor shaft at both ends of the frame. a pair of bearing housings disposed on the inner circumferential side via a bearing bracket; a pair of bearings disposed on the inner circumferential side of the pair of bearing housings and rotatably supporting the rotor shaft; and a pair of bearings fixed to the bearing bracket; The rotary support member is arranged to be movable in the axial direction of the rotor shaft with respect to the bearing bracket, and the support receiving member is fixed to the rotor shaft and comes into contact with the rotor shaft when the rotation support member moves in the axial direction.

Grease filled in the bearings of vehicle main electric motors tends to deteriorate gradually because heat inside the machine and dust in the outside air enter the bearings due to negative pressure caused by the cooling airflow. Furthermore, since the base oil contained in the grease is easily depleted, it is necessary to periodically disassemble and maintain the bearing and refill it with grease to obtain an optimal grease containing sufficient base oil.
When disassembling and maintaining the bearings of the vehicle main electric motor of Patent Document 1, first, the rotary support member is moved in the axial direction and brought into contact with the support receiving member, and the rotor shaft is held by the frame via the bearing bracket. put. This allows the bearing to be replaced without completely disassembling the stator core, rotor core, rotor shaft, etc. of the main motor.

Japanese Patent Application Publication No. 2008-994981

By the way, in the disassembly and maintenance of the bearing of a vehicle traction motor disclosed in Patent Document 1, it is necessary to hold the rotor shaft in a frame before pulling out the bearing from the rotor shaft, so the disassembly and maintenance of the bearing is greatly reduced. I can't say that there is.
Further, a rotation support member and a support receiving member are required for supporting the rotor shaft with the frame, and there is a problem in terms of manufacturing costs due to an increase in the number of parts.
Therefore, we have developed a method for replacing bearings in traction motors for vehicles that does not require a member to hold the rotor shaft when the bearing is pulled out from the rotor shaft, which greatly reduces the labor required for disassembly and maintenance of the bearing, and also reduces manufacturing costs. It is an object of the present invention to provide a bearing structure for a vehicular traction motor and a vehicular traction motor that can achieve the following.

In order to achieve the above object, a bearing replacement method for a traction motor for a vehicle according to one aspect of the present invention includes a cylindrical case, a stator core fixed to an inner circumferential wall of the case, and a bearing disposed inside the stator core. a rotor core fixed to the rotor shaft, a pair of side brackets connected to both ends of the case in the axial direction to accommodate the stator core and the rotor core, and a pair of side brackets formed on the inner diameter side of the pair of side brackets through which the rotor shaft passes. A main body for a vehicle, comprising: a bracket inner diameter portion, a pair of bearing housings fixed to the outer walls of the pair of side brackets, and a pair of bearings held by the pair of bearing housings to rotatably support a rotor shaft. A method for replacing the pair of bearings of an electric motor, the method comprising: releasing the fixation of the bearing housing from the side bracket, and removing the bearing and the bearing housing from the rotor shaft while the rotor shaft is temporarily supported by the inner diameter of the bracket of the side bracket. and a step of attaching a new bearing and bearing housing to the rotor shaft and fixing the bearing housing to the outer wall of the side bracket. A tapered circumferential surface on the bracket side is formed, and the bearing housing is formed with a tapered circumferential surface on the housing side that comes into surface contact with the tapered circumferential surface on the bracket side, so that a new bearing can be mounted on the rotor shaft. Sometimes, the centering of the bearing is adjusted by fixing the bearing housing to the side bracket with the tapered peripheral surface on the bracket side and the tapered peripheral surface on the housing side in contact with each other.

Further, a bearing structure for a vehicle traction motor according to one aspect of the present invention includes a cylindrical case, a stator core fixed to an inner circumferential wall of the case, and a rotor fixed to a rotor shaft disposed inside the stator core. an iron core, a pair of side brackets connected to both axial ends of the case and housing the stator iron core and the rotor iron core, a bracket inner diameter portion formed on the inner diameter side of the pair of side brackets and through which the rotor shaft passes; a pair of bearing housings fixed to the outer wall of the side bracket, and a pair of bearings held by the pair of bearing housings to rotatably support the rotor shaft; When the bearing and bearing housing are removed from the rotor shaft, the inner diameter part of the side bracket temporarily supports the rotor shaft, and the outer wall of the side bracket has a bracket side whose diameter gradually increases toward both ends of the rotor shaft. A tapered circumferential surface is formed, and the bearing housing is formed with a housing-side tapered circumferential surface that abuts the bracket-side taper circumferential surface in surface contact. By fixing the bearing housing to the side bracket while they are in contact with each other, the centering of the bearing can be adjusted.

Furthermore, a vehicular traction motor according to one aspect of the present invention includes a cylindrical case, a stator core fixed to an inner circumferential wall of the case, a rotor core fixed to a rotor shaft disposed inside the stator core. a pair of side brackets having a bracket-side tapered peripheral surface whose diameter gradually increases toward both ends of the rotor shaft on the outer wall, and connected to both axial ends of the case to house the stator core and the rotor core; The inner diameter part of the bracket is formed on the inner diameter side of the pair of side brackets and the rotor shaft passes through it, and the tapered circumferential surface on the housing side is formed in surface contact with the tapered circumferential surface on the bracket side. A rotor shaft includes a pair of bearing housings fixed to an outer wall, and a pair of bearings that are held by the pair of bearing housings and rotatably support the rotor shaft, and the tapered circumferential surface on the bracket side and the tapered circumferential surface on the housing side are brought into contact with each other. The bearing housing is fixed to the side bracket in this state.

According to the bearing replacement method for a vehicle traction motor according to the present invention, when the bearing is pulled out from the rotor shaft, the inner diameter portions of the brackets of the pair of side brackets temporarily support the rotor shaft, so that the time required for disassembling and maintaining the bearing is reduced. Labor can be significantly reduced.
Furthermore, according to the bearing structure for a vehicle traction motor and the vehicle traction motor according to the present invention, there is no need to provide a component that holds the rotor shaft, which is used only when the bearing is pulled out from the rotor shaft, so manufacturing costs can be reduced. can be achieved.

1 is an axial half-sectional view showing a vehicle main electric motor according to a first embodiment of the present invention. FIG. 2 is a diagram showing a main part of a bearing structure of a vehicle traction motor according to a first embodiment. It is a figure which shows the operation|movement which pulls out the 2nd housing which comprises a bearing housing in the bearing structure of the main electric motor for vehicles of 1st Embodiment. It is a figure which shows the operation|movement which pulls out the 1st housing and bearing which constitute a bearing housing in the bearing structure of the main electric motor for vehicles of 1st Embodiment. It is a figure showing the main part of the bearing structure of the main electric motor for vehicles of a 2nd embodiment concerning the present invention. FIG. 7 is a diagram illustrating an operation of pulling out the first and second housings and the bearing that constitute the bearing housing in the bearing structure of the vehicular main electric motor of the second embodiment.

Next, embodiments according to the present invention will be described with reference to the drawings. In the description of the drawings below, the same or similar parts are designated by the same or similar symbols. However, it should be noted that the drawings are schematic and the relationship between thickness and planar dimensions, the ratio of the thickness of each layer, etc. are different from reality. Therefore, the specific thickness and dimensions should be determined with reference to the following explanation. Furthermore, it goes without saying that the drawings include portions with different dimensional relationships and ratios.
In addition, the embodiments shown below exemplify devices and methods for embodying the technical idea of the present invention. etc. are not specified as those listed below. The technical idea of the present invention can be modified in various ways within the technical scope defined by the claims.

[First embodiment]
FIG. 1 shows a main electric motor 1 for a vehicle according to a first embodiment of the present invention, which is attached to a bogie of a railway vehicle and drives wheels.
This main electric motor 1 for a vehicle includes a cylindrical case 2 formed of a metal material, a pair of side brackets 3 and 4 connected at both ends of the case 2 in the axial direction, and fixed to the inner circumference of the case 2. A stator core 5 with stator coils 5a protruding from both end faces, a rotor core 7 fixed to a rotor shaft 6 with substantially the same axial length inside the stator core 5, and a pair of side brackets 3, 4. A pair of bearing housings 8, 9 fixed to an outer wall on the inner diameter side, and a pair of bearings 10, 11 arranged on the inner diameter side of the pair of bearing housings 8, 9 to rotatably support the rotor shaft 6. ing.

The pair of bearings 10 and 11 each include annular inner rings 10a and 11a, outer rings 10b and 11b, and a plurality of rolling elements 10c and 11c.
One of the side brackets 3 includes an outer diameter bracket 13 that connects to the axial end of the case 2, and a bracket inner diameter portion 15 that is continuous with the outer diameter bracket 13 via an intermediate bracket 14.
A sleeve 7a extending axially outward is formed on the inner diameter portion of the rotor core 7 that is in contact with the outer periphery of the rotor shaft 6, and an annular groove 7b is formed on the outer periphery of the end side of the sleeve 7a. ing. A plurality of annular recesses 7c are formed extending in the axial direction at positions radially outward from the sleeve 7a.

The bracket inner diameter portion 15 extends in the radial direction orthogonal to the axis P of the rotor shaft 6 while being close to the axial end surface of the rotor core 7 . The inner diameter portion 15a of this bracket inner diameter portion 15 is inserted into the outer periphery of the sleeve 7a of the rotor core 7. A plurality of annular convex portions 15b are formed on the inner diameter portion of the bracket 15, and the plurality of annular convex portions 15b fit into the plurality of annular concave portions 7c of the rotor core 7, and a labyrinth structure is adopted by the plurality of annular concave portions 7c and the annular convex portions 15b. ing.

Further, on the outer wall of the intermediate bracket 14, a first bracket side tapered peripheral surface 14a is formed on the bracket inner diameter part 15 side, a second bracket side tapered peripheral surface 14b is formed on the outer diameter side bracket 13 side, and the first bracket side taper peripheral surface 14b is formed on the outer diameter side bracket 13 side. An axially perpendicular circumferential surface 14c extending in a direction perpendicular to the axis P is formed between the side tapered circumferential surface 14a and the second bracket side tapered circumferential surface 14b. The first bracket-side tapered circumferential surface 14a and the second bracket-side tapered circumferential surface 14b are surfaces whose diameters gradually increase from the bracket inner diameter portion 15 toward the outer diameter side bracket 13.
Further, the other bracket 4 of the pair of brackets 3 and 4 also includes an outer diameter side bracket 13, an intermediate bracket 14, and a bracket inner diameter part 15, like the one bracket 3. A bracket-side tapered peripheral surface 14a, a second bracket-side tapered peripheral surface 14b, and an axially right peripheral surface 14c are formed.

As shown in FIG. 2, one bearing housing 8 includes an annular first housing 16 that abuts the outer wall of the bracket inner diameter portion 15, is inserted into the outer periphery of the sleeve 7a of the rotor core 7, and supports the bearing 10; 10 and an annular second housing 17 that supports the first housing 16.
On the inside of the first housing 16, an axial support surface 16a and an axial support surface 16b are formed as surfaces perpendicular to each other. ) are placed in contact with each other, and the outer circumference of the outer ring 10b is placed in contact with the axial support surface 16b. A grease pocket 16c for storing grease is formed on the surface of the axial support surface 16a facing the bearing 10. The inner diameter portion of the first housing 16 is inserted into the outer periphery of the sleeve 7a in which the annular groove 7b is formed. An engaging circumferential groove 20 is formed on the outer periphery of the first housing 16 along the axis P of the rotor shaft 6.

The inner diameter portion of the second housing 17 is inserted into the outer periphery of the rotor shaft 6 via the collar 23. An annular groove 23a is formed on the outer periphery of the collar 23. The second housing 17 has an axial support surface 17a and an axial support surface 17b that are orthogonal to each other. A grease pocket 17e for storing grease is formed on the surface of the axial support surface 17b facing the bearing 10.
On the outer diameter side of the second housing 17, a first housing side tapered circumferential surface 17c and a second housing side tapered circumferential surface are in surface contact with the first bracket side tapered circumferential surface 14a and the second bracket side tapered circumferential surface 14b of the intermediate bracket 14. A peripheral surface 17d is formed. Further, the second housing 17 is formed with a bolt through hole 18 penetrating in the axial direction and a screw hole 19 for housing movement, and a screw hole closing bolt B2 is screwed into the screw hole 19 for housing movement. .

Further, the intermediate bracket 14 has a bracket side screw hole 14d formed therein. This bracket-side screw hole 14d has a first housing-side tapered peripheral surface 17c and a second housing-side tapered peripheral surface 17d of the second housing 17 on the first bracket-side tapered peripheral surface 14a and the second bracket-side tapered peripheral surface 14b. When the axial support surface 17a of the second housing 17 contacts the other axial side surface of the bearing 10, and the axial support surface 17b of the second housing 17 contacts the outer ring 10b of the bearing 10, the bolt It faces the through hole 18 .
Then, when the housing bolt B1 inserted into the bolt through hole 18 is screwed into the bracket side screw hole 14d of the intermediate bracket 14, the first housing side tapered circumferential surface 17c and the second housing side tapered circumferential surface 17d of the second housing 17 are screwed into the bracket side screw hole 14d of the intermediate bracket 14. is in close contact with the first bracket-side tapered peripheral surface 14a and the second bracket-side tapered peripheral surface 14b, the axial support surface 17a of the second housing 17 supports the bearing 10 in the axial direction and the first housing 16, and the shaft The directional support surface 17b supports the bearing 10 in the radial direction.

Further, the other bearing housing 9 of the pair of bearing housings 8 and 9 is also formed in the same shape as one of the bearing housings 8, and has an annular groove that supports the bearing 11 by contacting the outer wall of the inner diameter portion 15 of the bracket. 1 housing 16, and an annular second housing 17 that supports the bearing 11 and the first housing 16.

[Bearing replacement method of first embodiment]
Next, a method for replacing the pair of bearings 10 and 11 from the vehicle main electric motor 1 having the above configuration will be described with reference to FIGS. 2 to 4.
When pulling out one of the bearings 10 from the rotor shaft 6, first, the screw hole closing bolt B2 screwed into the housing movement screw hole 19 is pulled out. Next, the housing bolt B1 screwed into the bracket side screw hole 14d of the intermediate bracket 14 is pulled out from the bracket side screw hole 14d and the bolt through hole 18, and screwed into the housing movement screw hole 19.

Next, as shown in FIG. 3, by increasing the screwing amount of the housing bolt B1 into the housing moving screw hole 19 and bringing the tip of the housing bolt B1 into contact with the axially right circumferential surface 14c of the intermediate bracket 14. , a state in which the first housing side tapered circumferential surface 17c and the second housing side tapered circumferential surface 17d of the second housing 17 are spaced apart from the first bracket side tapered circumferential surface 14a and the second bracket side tapered circumferential surface 14b of the intermediate bracket 14. Then, the second housing 17 is moved to one end in the axial direction (to the right in FIG. 3) and removed from the outer periphery of the rotor shaft 6. Next, the collar 23 disposed on the outer periphery of the rotor shaft 6 is also removed from the outer periphery of the rotor shaft 6.

Next, as shown in FIG. 4, the engagement claw 22f of the puller 22 is engaged with the engagement circumferential groove 20 of the first housing 16 at one end of the rotor shaft 6.
The puller 22 includes a threaded shaft 22a, a rotary handle 22b provided at one end of the threaded shaft 22a, a puller body 22d provided with a female thread 22c screwed into the male thread of the threaded shaft 22a, and a puller main body 22d provided with an outer circumference of the puller main body 22d. It includes a plurality of engaging members 22e connected at equal intervals in the circumferential direction and protruding outward, and an engaging claw 22f provided at the tip of each engaging member 22e.
The threaded shaft 22a of the puller 22 is arranged coaxially with the axis P of the rotor shaft 6, and with the other end of the threaded shaft 22a in contact with the end surface of one end of the rotor shaft 6, the plurality of engaging members 22e The engaging claw 22f is engaged with the engaging circumferential groove 20 of the first housing 16.

Next, by operating the rotation handle 22b, the screw shaft 22a is rotated in a predetermined direction to move the puller main body 22d toward one end of the screw shaft 22a (to the right in FIG. 3). The plurality of engagement members 22e move toward one end of the screw shaft 22a together with the puller main body 22d, so that the engagement circumferential groove 20 engages with the engagement claw 22f of the plurality of engagement members 22e. The first housing 16 and the bearing 10 whose one axial side surface is in contact with the axial support surface 16a of the first housing 16 move toward one end of the rotor shaft 6. Thereby, the first housing 16 and the bearing 10 can be pulled out from the outer periphery of the rotor shaft 6.

At this time, the rotor shaft 6 from which the bearing housing 8 (first housing 16, second housing 17) and bearing 10 have been pulled out is inserted into the inner diameter part 15a of the bracket inner diameter part 15 of the side bracket 3 through the sleeve 7a of the rotor core 7. tentatively supported.
Also, when pulling out the other bearing 11 from the rotor shaft 6, the same procedure as in the method for pulling out the one bearing 10 from the rotor shaft 6 described above is performed. Then, the rotor shaft 6 from which the bearing housing 9 (first housing 16, second housing 17) and bearing 11 have been pulled out is also inserted into the inner diameter part 15a of the bracket inner diameter part 15 of the side bracket 3 via the sleeve 7a of the rotor core 7. Tentatively supported.

On the other hand, when attaching a new bearing 10 that has been disassembled and maintained to the vehicle traction motor 1, the inner diameter part of the first housing 16 is first attached to the sleeve 7a of the rotor core 7, and the inner diameter part of the bracket is brought into contact with the outer wall of the bracket inner diameter part 15. Let them come into contact with you. Next, a new bearing 10 is attached to the outer periphery of the rotor shaft 6.
Next, after inserting the collar 23 onto the outer periphery of the rotor shaft 6, the second housing 17 is attached to the outer periphery of the collar 23. Then, the second housing 17 is moved toward the first housing 16 and the bearing 10 arranged on the outer periphery of the rotor shaft 6. Then, with the second housing 17 in contact with the outer wall of the intermediate bracket 14, the housing bolt B1 inserted through the bolt through hole 18 of the second housing 17 is screwed into the bracket side screw hole 14d of the intermediate bracket 14. As a result, a new bearing 10 is attached to the vehicle main electric motor 1.

At this time, in the bearing 10 supported by the first housing 16 and the second housing 17, the first housing side tapered circumferential surface 17c of the second housing 17 and the second housing side tapered circumferential surface 17d are connected to the first bracket of the intermediate bracket 14. By being placed in surface contact with the side tapered circumferential surface 14a and the second bracket side tapered circumferential surface 14b, centering adjustment is performed to match the axis P of the rotor shaft 6.
Furthermore, when disassembling and maintaining the other new bearing 11 and installing it on the vehicle traction motor 1, the procedure is similar to the method for installing the above-described new bearing 10 on the vehicle traction motor 1.

[Effects of the first embodiment]
According to the first embodiment described above, the rotor shaft 6 from which the pair of bearing housings 8, 9 and the pair of bearings 10, 11 have been pulled out is attached to the inner diameter part 15a of the bracket inner diameter part 15 of the pair of side brackets 3, 4. Since the bearings are temporarily supported via the sleeve 7a of the iron core 7, the labor required for disassembly and maintenance of the bearings 10 and 11 can be significantly reduced.
In addition, the vehicle traction motor 1 of the first embodiment does not require a component to support the rotor shaft 6, which is used only when pulling out the bearings 10 and 11 from the rotor shaft 6, and is superior to conventional vehicle traction motors. Since the number of parts can be reduced, manufacturing costs can be reduced.

Further, as shown in FIG. 3, by increasing the screwing amount of the housing bolt B1 into the housing moving screw hole 19 and bringing the tip of the housing bolt B1 into contact with the axially right circumferential surface 14c of the intermediate bracket 14. , the second housing 17 can be moved to the end in the axial direction and easily removed from the outer periphery of the rotor shaft 6. Further, as shown in FIG. 4, when the screw shaft 22a is rotated in a predetermined direction by operating the rotation handle 22b of the puller 22 and the puller main body 22d is moved toward the end of the screw shaft 22a, the puller main body 22d At the same time, the plurality of engaging members 22e move toward one end of the screw shaft 22a, and the first housing 16 and the bearing 10 (11) move toward the end of the rotor shaft 6. The bearing 10 (11) can also be easily pulled out from the outer periphery of the rotor shaft 6.

In addition, when installing new bearings 10 and 11 that have been disassembled and maintained on the vehicle main motor 1, the first housing side tapered circumferential surface 17c and the second housing side tapered circumferential surface 17d of the second housing 17 are connected to the intermediate bracket 14. The centers of the bearings 10 and 11 are aligned with the axis P of the rotor shaft 6 by being arranged in close contact (surface contact) with the first bracket-side tapered peripheral surface 14a and the second bracket-side tapered peripheral surface 14b. Since the extension adjustment can be performed automatically, the assembly accuracy of the bearings 10 and 11 can be improved.

[Second embodiment]
Next, FIGS. 5 and 6 show main parts of a bearing structure of a vehicle main electric motor 1 according to a second embodiment of the present invention. Components that are the same as those shown in FIGS. 1 to 4 are designated by the same reference numerals, and description thereof will be omitted.
The bearing housing 8 of this embodiment includes annular first and second housings 25 and 26 that support the bearing 10 by contacting the outer wall of the bracket inner diameter portion 15, as shown in FIG. These first and second housings 25 and 26 are divided into two in the direction of the axis P of the rotor shaft 6.

On the inside of the first housing 25, an axial support surface 25a and an axial support surface 25b are formed as surfaces perpendicular to each other, and one axial side surface of the bearing 10 (left side in FIG. 5) is formed on the axial support surface 25a. ) is in contact with the outer ring 10b, and a portion of the outer circumference of the outer ring 10b is in contact with the axial support surface 25b. A first housing-side tapered circumferential surface 25c is formed on the outer periphery of the first housing 25. The first housing-side tapered circumferential surface 25c abuts the first bracket-side tapered circumferential surface 14a of the intermediate bracket 14 in surface contact.
On the inner diameter side of the second housing 26, an axial support surface 26a and an axial support surface 26b are formed as surfaces that are orthogonal to each other. The other axial side surface of the bearing 10 is in contact with the axial support surface 26a, and the remaining outer periphery of the outer ring 10b is in contact with the axial support surface 26b. A second housing-side tapered peripheral surface 26c is formed on the outer periphery of the second housing 26. The second housing-side tapered peripheral surface 26c abuts against the second bracket-side tapered peripheral surface 14b of the intermediate bracket 14 in surface contact.

The first and second housings 25 and 26 are formed with bolt through holes 27 and 28 that penetrate in the axial direction, and the housing movement screw hole 14d of the intermediate bracket 14 faces the bolt through holes 27 and 28. ing. Then, when the housing bolt B1 inserted into the bolt through holes 27 and 28 is screwed into the bracket-side screw hole 14d of the intermediate bracket 14, the first housing-side tapered peripheral surface 25c of the first housing 25 and the first housing-side tapered peripheral surface 25c of the second housing 26 are The first and second housings 25 and 26 support the bearing 10 with the second housing side tapered circumferential surface 26c in close contact with the first bracket side tapered circumferential surface 14a and the second bracket side tapered circumferential surface 14b of the intermediate bracket 14. do.

Further, a connecting screw hole 29 is formed in the first housing 25, and a connecting screw hole 30 corresponding to the connecting screw hole 29 of the first housing 25 is formed penetrating through the second housing 26. The first and second housings 25 and 26 are connected by screwing in the bolt B3.
Furthermore, the second housing 26 is formed with a housing movement screw hole 31 that faces the axially right circumferential surface of the intermediate bracket 14 and penetrates in the axial direction. is screwed in.
Although not shown, the other bearing housing 9 of the pair of bearing housings 8 and 9 is also formed in the same shape as one of the bearing housings 8, and supports the bearing 11 by coming into contact with the outer wall of the inner diameter portion 15 of the bracket. The first and second annular housings 25 and 26 are provided.

[Bearing replacement method of second embodiment]
When pulling out one of the bearings 10 from the rotor shaft 6, first, the screw hole closing bolt B2 screwed into the housing movement screw hole 31 is pulled out. Next, the housing bolt B1 screwed into the bracket side screw hole 14d of the intermediate bracket 14 is pulled out from the bracket side screw hole 14d and the bolt through holes 27 and 28, and screwed into the housing movement screw hole 31.

Next, as shown in FIG. 6, by increasing the screwing amount of the housing bolt B1 into the housing moving screw hole 31 and bringing the tip of the housing bolt B1 into contact with the axially right circumferential surface 14c of the intermediate bracket 14. , the first and second housings 25 and 26, the collar 23, and the bearing 10 are moved to one end in the axial direction (to the right in FIG. 6) and removed from the outer periphery of the rotor shaft 6.
At this time, the rotor shaft 6 from which the bearing housing 8 (first housing 25, second housing 26) and bearing 10 have been pulled out is inserted into the inner diameter part 15a of the bracket inner diameter part 15 of the side bracket 3 via the sleeve 7a of the rotor core 7. tentatively supported.

Also, when pulling out the other bearing 11 from the rotor shaft 6, the same procedure as in the method for pulling out the one bearing 10 from the rotor shaft 6 described above is performed. Then, the rotor shaft 6 from which the bearing housing 9 (first housing 25, second housing 26) and bearing 11 have been pulled out is inserted into the inner diameter part 15a of the bracket inner diameter part 15 of the side bracket 4 via the sleeve 7a of the rotor core 7. Tentatively supported.
On the other hand, when installing a new bearing 10 that has been disassembled and maintained on the vehicle main electric motor 1, first, the new bearing 10 with the bearing housing 9 (first housing 25, second housing 26) installed on the outer periphery is attached to the rotor shaft. The collar 23 is attached to the outer periphery of the second housing 26 from one end side, and the collar 23 is attached to the inner diameter portion of the second housing 26. Then, the housing bolt B1 inserted into the bolt through holes 27 and 28 is screwed into the bracket side screw hole 14d of the intermediate bracket 14. As a result, a new bearing 10 is attached to the vehicle main electric motor 1.

At this time, the bearing 10 supported by the first housing 25 and the second housing 26 has a tapered circumferential surface 25c on the first housing side of the first housing 25 and a tapered circumferential surface 26c on the second housing side of the second housing 26 in the intermediate bracket. By being arranged in surface contact with the first bracket-side tapered circumferential surface 14a and the second bracket-side tapered circumferential surface 14b of No. 14, centering adjustment is performed so as to match the axis P of the rotor shaft 6.
Furthermore, when disassembling and maintaining the other new bearing 11 and installing it on the vehicle traction motor 1, the procedure is similar to the method for installing the above-described new bearing 10 on the vehicle traction motor 1.

[Effects of second embodiment]
According to the second embodiment, similarly to the first embodiment, the rotor shaft 6 from which the pair of bearing housings 8, 9 and the pair of bearings 10, 11 have been pulled out is located at the bracket inner diameter portion 15 of the pair of side brackets 3, 4. Since the rotor core 7 is temporarily supported by the inner diameter portion 15a of the rotor core 7 through the sleeve 7a of the rotor core 7, the labor required for disassembly and maintenance of the bearings 10 and 11 can be significantly reduced.
Further, in the second embodiment, there is no need to provide any parts to support the rotor shaft 6 when the bearings 10 and 11 are pulled out from the rotor shaft 6, and the number of parts can be reduced compared to the conventional traction motor for a vehicle. Therefore, manufacturing costs can be reduced.

In addition, when installing new bearings 10 and 11 that have been disassembled and maintained on the vehicle main motor 1, the first housing side tapered circumferential surface 25c of the first housing 25 and the second housing side tapered circumferential surface 26c of the second housing 26 are arranged in surface contact with the first bracket-side tapered circumferential surface 14a and the second bracket-side tapered circumferential surface 14b of the intermediate bracket 14, so that the bearings 10, 11 are aligned with the axis P of the rotor shaft 6. Since the centering adjustment can be performed automatically, the assembly accuracy of the bearings 10 and 11 can be improved.

1 Main motor for vehicle 2 Case 3, 4 Side bracket 5 Stator core 6 Rotor shaft 7 Rotor core 7a Sleeve 7b Annular groove 7c Annular recess 8, 9 Bearing housing 10, 11 Bearing 10a, 11a Inner ring 10b, 11b Outer ring 10c, 11c Moving body 13 Outer diameter side bracket 14 Intermediate bracket 14a First bracket side tapered circumferential surface (bracket side tapered circumferential surface)
14b Second bracket side tapered peripheral surface (bracket side tapered peripheral surface)
14c Shaft-right peripheral surface 14d Bracket side screw hole 15 Bracket inner diameter part 15a Inner diameter part 15b Annular convex part 16 First housing 16a Axial direct support surface 16b Axial support surface 16c Grease pocket 17 Second housing 17a Axial direct support surface 17b Axial direction Support surface 17c First housing side tapered circumferential surface (housing side tapered circumferential surface)
17d Second housing side tapered circumferential surface (housing side tapered circumferential surface)
17e Grease pocket 18 Bolt through hole 19 Housing screw hole (screw hole)
20 Engagement circumferential groove 22 Puller 22a Screw shaft 22b Rotating handle 22c Female screw 22d Puller body 22e Engagement member 22f Engagement claw 25 First housing 25a Direct support surface 25b Axial support surface 25c 1 housing side tapered circumference 26 2nd housing 26a Axial support surface 26b Axial support surface 26c Second housing side tapered peripheral surface 27, 28 Bolt through holes 29, 30 Connecting screw hole 31 Housing movement screw hole B1, B3 Housing bolt B2 Screw hole blocking bolt

Claims (9)

a cylindrical case, a stator core fixed to an inner circumferential wall of the case, a rotor core fixed to a rotor shaft disposed inside the stator core, and a stator core connected to both axial ends of the case. and a pair of side brackets that accommodate the rotor core, a bracket inner diameter portion formed on the inner diameter side of the pair of side brackets and through which the rotor shaft passes, and a pair fixed to the outer wall of the pair of side brackets. A method for replacing the pair of bearings of a vehicle main electric motor, comprising: a bearing housing; and a pair of bearings that are held by the pair of bearing housings and rotatably support the rotor shaft, the method comprising:
releasing the fixation of the bearing housing to the side bracket and removing the bearing and the bearing housing from the rotor shaft while the rotor shaft is temporarily supported by the inner diameter portion of the bracket of the side bracket;
mounting a new bearing and the bearing housing on the rotor shaft, and fixing the bearing housing to the outer wall of the side bracket ,
The outer wall of the side bracket is formed with a bracket-side tapered circumferential surface whose diameter gradually increases toward the end of the rotor shaft, and the bearing housing is provided with a bracket-side tapered circumferential surface in surface contact with the bracket-side tapered circumferential surface. A tapered peripheral surface on the housing side that comes into contact is formed,
When installing the new bearing on the rotor shaft, the bearing housing is fixed to the side bracket with the bracket-side tapered circumferential surface and the housing-side tapered circumferential surface in contact with each other. A bearing replacement method for a traction motor for a vehicle, characterized in that centering adjustment is performed . The bearing housing includes a first housing that is in contact with the inner diameter portion of the bracket and holds the bearing, and a second housing that is adjacent to the first housing and holds the bearing at a position spaced apart from the inner diameter portion of the bracket. an engagement circumferential groove is formed in the axial outer circumference of the first housing, and a screw hole passing through toward the outer wall of the side bracket is formed in the second housing;
In the step of extracting the bearing and the bearing housing from the rotor shaft,
releasing the fixation of the first housing and the second housing to the side bracket;
The tip of a bolt screwed into the screw hole of the second housing is brought into contact with the outer wall of the side bracket, and the amount of screwing of the bolt into the screw hole is increased, so that the second housing is connected to the end of the rotor shaft. While moving it to the side,
An engaging pawl of a puller disposed at the end of the rotor shaft is engaged with the engaging circumferential groove of the first housing, and by operation of the puller, the first housing and the bearing are moved together with the engaging pawl. 2. The method of replacing a bearing for a vehicle main electric motor according to claim 1, wherein the bearing is moved toward an end of the rotor shaft. The bearing housing includes a first housing that is in contact with the inner diameter portion of the bracket and holds the bearing, and a second housing that is adjacent to the first housing and holds the bearing at a position spaced apart from the inner diameter portion of the bracket. The second housing is formed with a screw hole penetrating toward the outer wall of the side bracket,
In the step of extracting the bearing and the bearing housing from the rotor shaft,
releasing the fixation of the first housing and the second housing to the side bracket, and fixing both the first housing and the second housing;
The tips of the bolts screwed into the screw holes of the second housing are brought into contact with the outer wall of the side bracket, and the amount of screwing of the bolts into the screw holes is increased. 2. The method of replacing a bearing for a main electric motor for a vehicle according to claim 1, wherein the bearing is moved toward an end of the rotor shaft. A cylindrical case,
a stator core fixed to the inner peripheral wall of the case;
a rotor core fixed to a rotor shaft disposed inside the stator core;
a pair of side brackets connected to both axial ends of the case and housing the stator core and the rotor core;
a bracket inner diameter portion formed on the inner diameter side of the pair of side brackets and through which the rotor shaft passes;
a pair of bearing housings fixed to the outer walls of the pair of side brackets;
a pair of bearings held by the pair of bearing housings and rotatably supporting the rotor shaft;
When the bearing housing is released from being fixed to the side bracket and the bearing and the bearing housing are removed from the rotor shaft, the bracket inner diameter portion of the side bracket temporarily supports the rotor shaft ,
The outer wall of the side bracket is formed with a bracket-side tapered peripheral surface that gradually increases in diameter toward both ends of the rotor shaft, and the bearing housing has a bracket-side tapered peripheral surface that is in surface contact with the bracket-side tapered peripheral surface. A tapered peripheral surface on the housing side that comes into contact is formed,
The vehicle main body is characterized in that centering adjustment of the bearing is performed by fixing the bearing housing to the side bracket with the bracket-side tapered circumferential surface and the housing-side tapered circumferential surface in contact with each other. Electric motor bearing structure. Each of the pair of bearing housings includes a first housing that abuts against the outer wall of the inner diameter portion of the bracket and abuts one axial end surface and outer periphery of the bearing, and a first housing that abuts the other axial end surface of the bearing and the first housing. a second housing formed with a housing-side tapered peripheral surface that contacts the outer periphery of the housing and contacts the bracket-side tapered peripheral surface in surface contact, and a housing bolt that passes through the second housing is attached to the side. 5. The bearing structure for a main electric motor for a vehicle according to claim 4, wherein the first and second housings fixed to the side bracket by screwing into the bracket support the bearing. Each of the pair of bearing housings is divided into two parts in the axial direction, and includes a first housing having a first housing-side tapered circumferential surface that is in surface contact with a part of the bracket-side tapered circumferential surface, and a first housing that has a first housing -side tapered circumferential surface that is in surface contact with a part of the bracket-side tapered circumferential surface; a second housing formed with a second housing- side tapered peripheral surface that makes surface contact with the other part of the second housing;
the first housing abuts an outer wall of the inner diameter portion of the bracket and abuts one axial end surface and a part of the outer periphery of the bearing;
the second housing contacts the other axial end surface and another part of the outer periphery of the bearing;
The vehicle according to claim 4, wherein a housing bolt passing through the second housing is screwed into the side bracket, so that the first and second housings fixed to the side bracket support the bearing. Main motor bearing structure. A cylindrical case,
a stator core fixed to the inner peripheral wall of the case;
a rotor core fixed to a rotor shaft disposed inside the stator core;
A bracket-side tapered peripheral surface whose diameter gradually increases toward both ends of the rotor shaft is formed on the outer wall, and a pair of sides are connected to both axial ends of the case and house the stator core and the rotor core. bracket and
a bracket inner diameter portion formed on the inner diameter side of the pair of side brackets and through which the rotor shaft passes;
a pair of bearing housings that are fixed to outer walls of the pair of side brackets and have housing-side tapered peripheral surfaces that abut surface contact with the bracket-side tapered peripheral surfaces;
a pair of bearings that are held by the pair of bearing housings and rotatably support the rotor shaft;
A main electric motor for a vehicle, wherein the bearing housing is fixed to the side bracket with the bracket-side tapered peripheral surface and the housing-side tapered peripheral surface in contact with each other. Each of the pair of bearing housings includes a first housing that abuts against the outer wall of the inner diameter portion of the bracket and abuts one axial end surface and outer periphery of the bearing, and a first housing that abuts the other axial end surface of the bearing and the first housing. a second housing formed with a housing-side tapered peripheral surface that contacts the outer periphery of the housing and contacts the bracket-side tapered peripheral surface in surface contact, and a housing bolt that passes through the second housing is attached to the side. 8. The main electric motor for a vehicle according to claim 7, wherein the first and second housings , which are screwed into the bracket and fixed to the side bracket, support the bearing. Each of the pair of bearing housings is divided into two parts in the axial direction, and includes a first housing having a first bracket-side tapered circumferential surface that is in surface contact with a part of the bracket-side tapered circumferential surface, and a first housing that has a first bracket-side tapered circumferential surface that is in surface contact with a part of the bracket-side tapered circumferential surface. a second housing formed with a second bracket-side tapered peripheral surface that makes surface contact with the other part of the housing;
the first housing abuts an outer wall of the inner diameter portion of the bracket and abuts one axial end surface and a part of the outer periphery of the bearing;
the second housing contacts the other axial end surface and another part of the outer periphery of the bearing;
The vehicle according to claim 7, wherein a housing bolt passing through the second housing is screwed into the side bracket, so that the first and second housings fixed to the side bracket support the bearing. traction motor.

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