WO2019214189A1

WO2019214189A1 - Double-bearing structure for positioning end of traction motor

Info

Publication number: WO2019214189A1
Application number: PCT/CN2018/114165
Authority: WO
Inventors: 李广; 郭晏麟; 马千柱; 刘晨晓; 黄晓云
Original assignee: 中车永济电机有限公司
Priority date: 2018-05-08
Filing date: 2018-11-06
Publication date: 2019-11-14
Also published as: CN108696037A

Abstract

Disclosed is a double-bearing structure for a positioning end of a traction motor, relating to the field of traction motors, and in particular, a double-bearing structure for a positioning end of a traction motor. The technical solution is as follows: a bearing housing is provided with a one-step stepped hole tapered from the inside to the outside, the stepped face of the stepped hole being located in the middle of the stepped hole; a cylindrical roller bearing and a four-point contact ball bearing are respectively mounted in the bearing housing from either end of the bearing housing; the outer ring of the cylindrical roller bearing is pressed by an inner bearing cap, so that the influence of the axial cumulative error caused by mounting from one direction can be reduced, avoiding the problem that the surface of an outer sealing ring cannot be pressed to be level. The present invention is mainly applied to a traction motor, and provided is a double-bearing structure for a positioning end of a traction motor sleeved on a rotary shaft.

Description

Double bearing structure of traction motor positioning end

Technical field

The invention relates to the field of traction motors, in particular to a double bearing structure of a traction motor positioning end.

Background technique

Traction motor refers to the motor used for traction on railway trunk electric locomotives, industrial and mining electric locomotives, electric drive diesel locomotives and various electric vehicles (such as battery vehicles, city trams, underground railway electric vehicles, etc.). The traction motor generally has two sets of bearings at both ends of the rotating shaft, one set is a positioning end bearing, and the other set is a floating end bearing. The existing traction motor generally adopts a combination of a cylindrical roller bearing with a rim on the outer ring and a four-point contact ball bearing as a classic configuration of the positioning end bearing, and the cylindrical roller bearing is used to carry the radial load, the four-point contact ball. The bearings are used to carry axial loads. In the field of traction motors, four-point contact ball bearings with inner rings assembled by two halves are often used, which makes the bearings have higher axial load carrying capacity. Referring to FIG. 1 , a bearing housing of a conventional double-bearing structure adopts a first-order stepped hole which is gradually expanded from the inside to the outside, and a stepped surface of the stepped hole is located at an inner end of the stepped hole, and when installed, the inner seal is firstly installed. Ring 5', cylindrical roller bearing outer ring, outer ring spacer 8' and four-point contact ball bearing outer ring are sequentially loaded into the bearing housing 2' from one direction, and then the assembly is placed on the already installed sleeve 3 ', cylindrical roller bearing inner ring 6', inner ring spacer 7' and four-point contact ball bearing inner ring 9' on the rotating shaft 4', and finally through the outer sealing ring 10' axial compression of the four-point contact ball bearing The ring is axially pressed against the inner ring of the four-point contact ball bearing through the tachometer 12'. Such a structure may cause unevenness of the outer seal ring end face due to the influence of the cumulative tolerance. Furthermore, the four-point contact ball bearing outer ring is compressed without axial floating space, so that the four-point contact ball bearing can withstand additional loads due to thermal expansion of the shaft or slight misalignment of the inner and outer rings. Eventually, the operating conditions of the four-point contact ball bearing deteriorated and even burned.

Summary of the invention

The invention aims to solve the technical problem that the cumulative tolerance of the double bearing structure of the positioning end of the existing traction motor is too large and the surface pressure of the outer sealing ring is uneven. To this end, the present invention proposes a double bearing structure for the positioning end of the traction motor.

The technical solution adopted by the present invention to solve the technical problem thereof is:

A double-bearing structure for a traction motor positioning end, comprising a fixedly disposed bearing seat (the so-called fixing is fixed to the motor shaft, preferably, the bearing seat is fixed on the end cover of the motor), and the bearing seat is provided with a stepped hole which is tapered inside and outside, a stepped surface of the stepped hole is located in a middle portion of the stepped hole, the stepped hole is formed by a first cylindrical hole located inside the stepped surface and a second cylindrical hole located outside the stepped surface The first cylindrical hole is sleeved with an outer ring spacer, the outer end surface of the outer ring spacer abuts on the step surface, and the inner end surface of the outer ring spacer is adjacently provided with an interference fit in the bearing The cylindrical roller bearing outer ring on the inner wall of the seat (the "inner" as used herein refers to the position near the middle of the rotating shaft and away from the end of the rotating shaft, and the "outer" refers to the position away from the middle of the rotating shaft and near the end of the rotating shaft. The inner bearing is fixed on the inner end surface of the bearing housing, and the inner bearing cover abuts the inner end surface of the outer ring of the cylindrical roller bearing, that is, through the inner portion. Bearing cap abuts cylindrical roller The inner end surface of the outer ring of the bearing and the outer end surface of the outer ring spacer abut the step surface to realize axial positioning of the component in the first cylindrical hole; the second cylindrical hole is sleeved with a four-point contact ball bearing outer ring, The bearing seat is further provided with an outer sealing ring fixed on the outer end surface of the bearing seat; the inner ring of the cylindrical roller bearing corresponding to the outer ring of the cylindrical roller bearing, the outer ring spacer and the outer ring of the four-point contact ball bearing, The inner ring of the spacer sleeve and the four-point contact ball bearing are sequentially arranged on the rotating shaft from the inner side to the outer side, and the inner end surface of the inner ring of the cylindrical roller bearing is adjacently provided with a sleeve fixed on the rotating shaft, the four points The inner ring of the contact ball bearing is assembled by an inner half ring and an outer half ring, and the outer end surface of the outer half ring is adjacently provided with a speed measuring sprocket fixed on the rotating shaft, that is, the inner ring is realized by the sleeve and the speed measuring sprocket Axial positioning of the components. During operation, the cylindrical roller bearing is subjected to radial load, and the four-point contact ball bearing is subjected to axial load. When installed, the cylindrical roller bearing and the four-point contact ball bearing are respectively fitted into the bearing seat from the inner and outer sides of the bearing housing. The outer ring of the cylindrical roller bearing is pressed by the inner bearing cap, which greatly reduces the influence of the axial cumulative error when loading from one direction.

Further, the width of the outer ring of the four-point contact ball bearing is smaller than the axial length of the second cylindrical hole (here, although the width of the outer ring of the four-point contact ball bearing is indicated to be smaller than the axial length of the second cylindrical hole, the person skilled in the art It is well known that the relative dimensions should be within a reasonable range and cannot be too different. This is only to ensure that the four-point contact ball bearing does not bear extra load. The four-point contact ball bearing outer ring is not compressed. During the operation of the motor, the shaft will be The thermal expansion occurs and axial deformation occurs, and the four-point contact ball bearing outer ring will move axially in the defined area along with the thermal expansion of the rotating shaft to avoid additional axial load. Further, the outer end surface of the outer ring of the four-point contact ball bearing is provided with a plurality of positioning slots, and the corresponding positioning slots on the inner end surface of the outer sealing ring are provided with a plurality of blind holes, and the corresponding blind holes and the positioning slots of each group are common A positioning pin is inserted through, and the positioning pin prevents the four-point contact ball bearing outer ring from rotating together with the rotating shaft.

Further, the outer ring spacer axially protrudes radially inward to form an annular partition, and the annular spacer of the outer ring spacer is provided with a fat-filling hole on both sides. The two bearing chambers can be supplemented with grease by the fat-filling holes, and the lubricating effect of the grease is improved as a whole.

Further, the outer end surface of the bearing housing is provided with an annular groove coaxial with the rotating shaft, and the annular groove is embedded with a sealing gasket, and the sealing gasket is pressed into the annular groove by the outer sealing ring. When installed, the outer sealing ring is pressed on the outer end surface of the bearing seat, which is a rigid contact, and the positioning effect is better, and the sealing gasket in the annular groove is pressed tightly to improve the sealing performance.

The invention provides a double bearing structure of a positioning end of a traction motor, the bearing seat is provided with a stepped hole of a first step which is tapered from the inside to the outside, and the step surface of the stepped hole is located in the middle of the stepped hole Cylindrical roller bearing and four-point contact ball bearing are respectively fitted into the bearing seat from the inner and outer sides of the bearing housing, and the outer ring of the cylindrical roller bearing is axially compressed by the inner bearing cover and the step surface, and the structure and the mounting manner are effective. The influence of the axial cumulative error when loading from one direction is reduced; in addition, the outer ring of the four-point contact ball bearing is not compressed, and the shaft is thermally expanded and axially deformed during the operation of the motor, and the four-point contact ball The outer ring of the bearing will move axially with the thermal expansion of the rotating shaft to avoid additional axial load; the annular baffle of the outer ring spacer is provided with a fat-filling hole on both sides, through which the two holes can be The bearing chambers act as a supplement to the grease, which improves the lubrication of the grease as a whole.

DRAWINGS

1 is a schematic view of a prior art mounting structure of the present invention;

Figure 2 is a schematic view of the mounting structure of the present invention.

detailed description

A double-bearing structure for a positioning end of a traction motor, comprising a fixed bearing housing 2 (the so-called fixing is fixed to the motor shaft 4, preferably, the bearing housing 2 is fixed on the end cover 1 of the motor), the bearing The seat 2 is provided with a stepped hole which is tapered from the inside to the outside, and a stepped surface 18 of the stepped hole is located at a middle portion of the stepped hole, the stepped hole is defined by a first cylindrical hole located inside the stepped surface 18 and at the step a second cylindrical hole on the outer side of the surface 18; the first cylindrical hole is sleeved with an outer ring spacer 17, and an outer end surface of the outer ring spacer 17 abuts on the step surface 18, the outer ring spacer The inner end surface of the sleeve 17 is adjacently provided with a cylindrical roller bearing outer ring 15 which is fitted over the inner wall of the bearing housing 2 (the term "inner" as used herein refers to a position near the middle of the rotating shaft 4 and away from the end of the rotating shaft 4, The term "outer" refers to a position away from the middle of the rotating shaft 4 near the end of the rotating shaft 4, and the inside and the outside are mentioned later. The bearing housing 2 is also provided with an inner bearing fixed to the inner end surface of the bearing housing 2 a cover 5, the inner bearing cap 5 abuts against an inner end surface of the outer ring 15 of the cylindrical roller bearing, That is, the inner end surface of the cylindrical roller bearing outer ring 15 is abutted by the inner bearing cover 5, and the outer end surface of the outer ring spacer 17 abuts the step surface 18 to realize axial positioning of the components in the first cylindrical hole; the second cylinder The hole is sleeved with a four-point contact ball bearing outer ring 16, and the bearing block 2 is further provided with an outer sealing ring 11 fixed on the outer end surface of the bearing housing 2; corresponding to the cylindrical roller bearing outer ring 15, the outer ring spacer The sleeve 17 and the four-point contact ball bearing outer ring 16 are provided with a cylindrical roller bearing inner ring 6, an inner ring spacer 7 and a four-point contact ball bearing inner ring 9 which are sequentially adjacent to each other on the rotating shaft 4 from the inside to the outside. The inner end surface of the inner ring 6 of the cylindrical roller bearing is adjacently provided with a sleeve 3 fixed on the rotating shaft 4, and the inner ring 9 of the four-point contact ball bearing is assembled by an inner half ring and an outer half ring, the outer half The outer end surface of the ring is adjacently provided with a speed measuring sprocket 13 fixed to the rotating shaft 4, that is, the axial positioning of the inner ring components is realized by the sleeve 3 and the speed measuring sprocket 13. During operation, the cylindrical roller bearing is subjected to radial load, and the four-point contact ball bearing is subjected to axial load. When installed, the cylindrical roller bearing and the four-point contact ball bearing are respectively fitted into the bearing seat from the inner and outer sides of the bearing housing 2, respectively. 2. The cylindrical roller bearing outer ring 15 is pressed by the inner bearing cap 5, greatly reducing the influence of the axial cumulative error when loaded from one direction.

Further, the width of the four-point contact ball bearing outer ring 16 is smaller than the axial length of the second cylindrical hole (here, although the width of the four-point contact ball bearing outer ring 16 is smaller than the axial length of the second cylindrical hole, It is well known in the field that the relative size should be within a reasonable range and cannot be too different. This is only to ensure that the four-point contact ball bearing does not bear extra load. The four-point contact ball bearing outer ring 16 is not pressed, and the motor is in operation. The shaft 4 undergoes thermal expansion to undergo axial deformation, and the four-point contact ball bearing outer ring 16 will move axially in the defined area along with the thermal expansion of the rotating shaft 4 to avoid additional axial load. Further, the outer end surface of the outer ring 16 of the four-point contact ball bearing is provided with a plurality of positioning slots, and the corresponding positioning slots on the inner end surface of the outer sealing ring 11 are provided with a plurality of blind holes, and each set of corresponding blind holes and positioning slots A positioning pin 10 is inserted through the positioning pin 10 to prevent the four-point contact ball bearing outer ring 16 from rotating together with the rotating shaft 4. Specifically, there are two positioning slots, and the two positioning slots are 180° with each other. The positioning pin 10 is mainly arranged to prevent the four-point contact ball bearing outer ring 16 from rotating along with the rotating shaft 4, thereby affecting the normal operation of the motor.

As a further improvement of the above technical solution, the outer ring spacer 8 protrudes radially inward from the axial direction to form an annular partition plate 17, and the annular partition plate 17 of the outer ring spacer 8 is provided with a fat-filling hole on both sides thereof. . The two bearing chambers can be supplemented with grease by the fat-filling holes, and the lubricating effect of the grease is improved as a whole.

As a further improvement of the above technical solution, the outer end surface of the bearing housing 2 is provided with an annular groove coaxial with the rotating shaft 4, and the annular groove is embedded with a gasket 12, and the gasket 12 is pressed by the outer sealing ring 11 In the annular groove. When installed, the outer sealing ring 11 is pressed against the outer end surface of the bearing housing 2, which is a rigid contact, and the positioning effect is better, and the sealing gasket 12 in the annular groove is pressed tightly to improve the sealing performance. Further, an outer bearing cover 14 is provided at the outer end of the rotating shaft 4, and the outer bearing cover 14 is fixed to the end cover 1 to protect the entire double bearing structure.

As a preferred connection structure of the bearing housing 2 and the outer sealing ring 11, the annular groove is uniformly distributed with a plurality of screw holes in the circumferential direction, and the outer sealing ring 11 is provided with a plurality of through holes corresponding to the screw holes, and the bolt passes through the through hole. The hole is screwed into the screw hole to fix the outer seal ring 11 and the bearing housing 2.

Preferably, the inner bearing cap 5 is bolted to the inner surface of the bearing housing 2.

The double bearing structure of the positioning end of the traction motor provided by the invention is installed by the following method:

a. The sleeve 3, the cylindrical roller bearing inner ring 6, the inner ring spacer 7 and the inner half ring of the four-point contact ball bearing inner ring 9 are fitted on the rotating shaft 4 to form a rotating shaft 4 assembly;

b. The outer ring spacer 8 is fitted into the first cylindrical hole to be placed on the inner end surface of the shoulder;

c. The cylindrical roller bearing outer ring 15 is pressed into the first cylindrical hole, so that the outer end surface abuts against the inner end surface of the outer ring spacer 8;

d. The inner bearing cap 5 is fixed to the inner end surface of the bearing housing 2 so as to abut against the inner end surface of the cylindrical roller bearing 6, preferably by bolt fixing;

e. Insert the assembled housing 2 assembly in step d (here, the bearing housing 2 assembly mainly includes the bearing housing 2 and the components installed in the bearing housing 2 or the end surface in step bd) into the assembled shaft 4 in step a. The assembly (where the shaft 4 assembly mainly includes the rotating shaft 4 and the components set on the rotating shaft 4);

f. The four-point contact ball bearing outer ring 16 is inserted into the second cylindrical hole, where the four-point contact ball bearing outer ring 16 is in clearance with the bearing seat 2, so the outer ring is finally inserted;

g. Pressing the outer half of the inner ring 9 of the four-point contact ball bearing into the rotating shaft 4;

h. Fixing the outer sealing ring 11 on the outer end surface of the bearing housing 2;

i. The speed detecting sprocket 13 is fixed to the rotating shaft 4 such that its inner end surface abuts against the outer end surface of the outer half ring of the four-point contact ball bearing inner ring 9.

Further to the above technical solution, the four-point contact ball bearing outer ring 16 is disposed on the inner wall of the bearing housing 2, and the four-point contact ball bearing is mainly used for axial positioning, so the gap installation is more convenient and easy.

Further, between the steps d and e, the rolling elements of the cylindrical roller bearing 6 are mounted on the outer ring 15 of the cylindrical roller bearing through the bracket; between the steps f and g, the rolling elements of the four-point contact ball bearing are passed through the bracket It is mounted on the outer ring 16 of the four-point contact ball bearing.

The above specific structure and size data are specifically described in the preferred embodiments of the present invention, but the present invention is not limited to the embodiments, and those skilled in the art can make it without departing from the spirit of the present invention. Various equivalent modifications or substitutions are intended to be included within the scope of the invention as defined by the appended claims.

Claims

A double-bearing structure for a positioning end of a traction motor, comprising a fixed bearing housing (2), characterized in that: the bearing seat (2) is provided with a stepped hole which is tapered from the inside to the outside, and the stepped hole a stepped surface (18) is located in a middle portion of the stepped hole, the stepped hole being composed of a first cylindrical hole located inside the step surface (18) and a second cylindrical hole located outside the step surface (18); the first cylinder An outer ring spacer (8) is sleeved in the hole, and an outer end surface of the outer ring spacer (8) abuts on the step surface (18), and the inner end surface of the outer ring spacer (8) is adjacent a cylindrical roller bearing outer ring (15) provided with an interference fit on the inner wall of the bearing housing (2), and the bearing seat (2) is further provided with an inner bearing cover fixed on the inner end surface of the bearing housing (2) ( 5), the inner bearing cap (5) abuts the inner end surface of the outer ring (15) of the cylindrical roller bearing; the second cylindrical hole is sleeved with a four-point contact ball bearing outer ring (16), the bearing seat (2) an outer sealing ring (11) fixed on the outer end surface of the bearing housing (2); corresponding to the cylindrical roller bearing outer ring (15), the outer ring spacer (8) and the four-point contact ball Cylindrical roller set by bearing outer ring (16) The bearing inner ring (6), the inner ring spacer (7) and the four-point contact ball bearing inner ring (9) are sequentially adjacent to each other from the inner side to the outer side of the rotating shaft (4), and the cylindrical roller bearing inner ring ( 6) The inner end surface is adjacently provided with a sleeve (3) fixed on the rotating shaft (4), and the inner ring (9) of the four-point contact ball bearing is assembled by the inner half ring (E) and the outer half ring (F) The outer end surface of the outer half ring (F) is adjacently provided with a speed measuring sprocket (13) fixed on the rotating shaft (4).
A double-bearing structure for a positioning end of a traction motor according to claim 1, wherein a width of said four-point contact ball bearing outer ring (16) is smaller than an axial length of said second cylindrical hole, said four-point contact The outer end surface of the outer ring (16) of the ball bearing is provided with a plurality of positioning slots, and the corresponding positioning slots on the inner end surface of the outer sealing ring (11) are provided with a plurality of blind holes, and each of the corresponding blind holes and the positioning slots are interspersed with a positioning. Pin (10).
The double-bearing structure of the positioning end of the traction motor according to claim 2 is characterized in that: two positioning slots are provided, and the two positioning slots are 180° apart from each other.
The double-bearing structure of the positioning end of the traction motor according to claim 1 or 2, wherein the outer ring spacer (8) protrudes radially inward from the axial center to form an annular partition (17), A grease-filling hole is provided on both sides of the annular partition (17) of the outer ring spacer (8).
The double-bearing structure of the positioning end of the traction motor according to claim 1, characterized in that: the outer end surface of the bearing seat (2) is provided with an annular groove coaxial with the rotating shaft (4), and the annular groove is A gasket (12) is fitted, and the gasket (12) is pressed into the annular groove by the outer sealing ring (11).
The double-bearing structure of the positioning end of the traction motor according to claim 5, wherein the annular groove is uniformly distributed with a plurality of screw holes in the circumferential direction, and the outer sealing ring (11) is provided with a plurality of through holes corresponding to the screw holes. The bolt is screwed into the screw hole through the through hole to fix the outer seal ring (11) and the bearing seat (2).
A positioning end double bearing structure for a traction motor according to claim 1, wherein said inner bearing cap (5) is bolted to an inner surface of the bearing housing (2).
A positioning end double bearing structure for a traction motor according to claim 1, wherein the installation is performed as follows:

a. The sleeve (3), the inner ring of the cylindrical roller bearing (6), the inner ring spacer (7) and the inner half ring of the four-point contact ball bearing inner ring (9) are placed on the rotating shaft (4). ;

b. The outer ring spacer (8) is fitted into the first cylindrical hole to be placed on the step surface (18);

c. press the cylindrical roller bearing outer ring (15) into the first cylindrical hole, so that the outer end surface abuts against the inner end surface of the outer ring spacer (8);

d. Fix the inner bearing cap (5) to the inner end surface of the bearing housing (2) so as to abut against the inner end surface of the outer ring (15) of the cylindrical roller bearing;

e. Insert the assembled bearing housing (2) assembly in step d into the assembled shaft (4) assembly in step a;

f. Insert the four-point contact ball bearing outer ring (16) into the second cylindrical hole;

g. Press the outer half of the inner ring (9) of the four-point contact ball bearing into the rotating shaft (4);

h. Fix the outer sealing ring (11) on the outer end surface of the bearing housing (2);

i. Fix the speed measuring sprocket (13) on the rotating shaft (4) so that its inner end surface abuts against the outer end surface of the outer half ring of the four-point contact ball bearing inner ring (9).
A double-bearing structure for a positioning end of a traction motor according to claim 8, wherein the four-point contact ball bearing outer ring (16) gap is fitted on the inner wall of the bearing housing (2).
A double-bearing structure for a positioning end of a traction motor according to claim 8, wherein the rolling elements of the cylindrical roller bearing are mounted on the outer ring (15) of the cylindrical roller bearing through the bracket between steps d and e. Between the steps f and g, the rolling elements of the four-point contact ball bearing are mounted on the four-point contact ball bearing outer ring (16) via the bracket.