CN109733435B

CN109733435B - Lubricating structure for variable-gauge wheel set and variable-gauge wheel set

Info

Publication number: CN109733435B
Application number: CN201910002745.4A
Authority: CN
Inventors: 郑静; 王旭; 乔青峰; 张峰; 赵长龙
Original assignee: CRRC Qingdao Sifang Co Ltd
Current assignee: CRRC Qingdao Sifang Co Ltd
Priority date: 2019-01-02
Filing date: 2019-01-02
Publication date: 2020-01-10
Anticipated expiration: 2039-01-02
Also published as: CN109733435A; EP3831688A4; JP7229376B2; JP2022508785A; WO2020140527A1; EP3831688B1; EP3831688A1; RU2758162C1

Abstract

The invention relates to the field of track gauge changing of rail vehicles, and provides a lubricating structure for a track gauge changing wheel set and the track gauge changing wheel set, which comprise wheels, axles and a sliding mechanism; the wheels are slidably arranged at two ends of the axle, the sliding mechanisms are respectively connected to the outer sides of the wheels and are positioned in the axle box bodies at two ends of the axle, and the wheels are unlocked and locked through the sliding mechanisms; a sealing structure is arranged between the inner side of the wheel and the axle, a first cavity is formed between the inner side of the wheel and the axle as well as between the inner side of the wheel and the sealing structure, a second cavity is formed between the outer side of the wheel and the slip mechanism, and a third cavity is formed between the slip mechanism and the axle box body; the wheel is provided with a first oil hole leading to the joint of the wheel and the axle, and the axle box body is provided with a second oil hole leading to the sliding mechanism. The invention can increase the lubrication of the friction surface, reduce the abrasion of key easy-abrasion parts and prolong the whole service life of the track-variable wheel pair.

Description

Lubricating structure for variable-gauge wheel set and variable-gauge wheel set

Technical Field

The invention relates to the technical field of rail vehicle variable track pitches, in particular to a lubricating structure for a variable track pitch wheel pair and the variable track pitch wheel pair.

Background

With the rapid development of global economy integration, the transnational passenger and cargo transportation is rapidly increased in recent years, but due to different rail gauges of railways of different countries, the transnational railway transportation is seriously hindered. In order to solve the problem that different track gauges of railways of various countries obstruct transnational railway transportation, a track gauge-variable wheel set is proposed, namely, when a train runs to a railway of other countries, the track gauge of the railway of other countries is adapted by changing the distance between wheels on the wheel set.

In the rail transfer process, a sliding mechanism on a wheel pair can slide relative to an axle along with the pushing and pressing of a ground guide rail, relative friction can occur between the wheel and the axle and between the sliding mechanism and the axle, and the lubricating design for key parts easy to wear is urgently needed.

Disclosure of Invention

Technical problem to be solved

The present invention is directed to solving at least one of the problems of the prior art or the related art.

The invention aims to provide a variable-gauge wheel pair and a lubricating structure for the same, so as to reduce the abrasion of key parts easy to abrade and prolong the whole service life of the variable-gauge wheel pair.

(II) technical scheme

In order to solve the technical problem, an embodiment of the present invention provides a lubricating structure for a track-variable wheel set, which includes a wheel, an axle and a sliding mechanism; the wheels are slidably arranged at two ends of the axle, the sliding mechanisms are respectively connected to the outer sides of the wheels and are positioned in the axle box bodies at two ends of the axle, and the wheels are unlocked and locked through the sliding mechanisms; a sealing structure is arranged between the inner side of the wheel and the axle, a first cavity is formed between the inner side of the wheel and the axle as well as between the inner side of the wheel and the sealing structure, a second cavity is formed between the outer side of the wheel and the slip mechanism, and a third cavity is formed between the slip mechanism and the axle box body; the wheel is provided with a first oil hole leading to the joint of the wheel and the axle, and the axle box body is provided with a second oil hole leading to the sliding mechanism.

In an embodiment of the present invention, the sliding mechanism includes an inner sleeve, the inner sleeve is in clearance fit with the axle, one end of the inner sleeve facing the wheel extends out of the axle box and is tightly connected with the wheel, a track gauge changing space is left between the extending end of the inner sleeve and the axle, and the track gauge changing space forms the second cavity.

In the embodiment of the invention, the sliding mechanism further comprises a rolling bearing and an outer sleeve, the inner sleeve, the rolling bearing and the outer sleeve are sequentially and tightly sleeved from inside to outside, and the outer sleeve is in clearance fit with the inner surface of the shaft box body; and a third cavity is formed between the outer end surface of the outer sleeve and the outer end cover of the shaft box body.

In the embodiment of the invention, bosses extending along the axial direction of the outer sleeve are respectively arranged on two opposite sides outside the outer sleeve, a plurality of grooves are arranged at intervals along the length direction of the bosses, the inner wall of the axle box body is provided with concave cambered surfaces corresponding to the grooves one by one, locking pins are arranged in locking spaces defined by the grooves and the concave cambered surfaces of the axle box body, and the axle box body is also provided with third oil injection holes communicated with the concave cambered surfaces.

In an embodiment of the invention, the third oil filling hole is formed in the side wall of the axle box body corresponding to the locking pin.

In an embodiment of the invention, an axial through hole in sliding fit with the outer sleeve is formed in the shaft box body, and the second oil filling hole is vertically arranged from the top and/or the bottom of the shaft box body and is communicated with the axial through hole.

In an embodiment of the invention, an oil storage tank is arranged on the axle in the radial direction between the inner side of the wheel and the sealing structure, and the first cavity is formed between the inner side of the wheel, the oil storage tank and the sealing structure.

In the embodiment of the invention, the sealing structure comprises an outer ring, an inner ring and an elastic sleeve, wherein the inner diameter of the outer ring is larger than the outer diameter of the inner ring, one end of the elastic sleeve is fixedly connected with the inner periphery of the outer ring, the other end of the elastic sleeve is fixedly connected with the outer periphery of the inner ring, and the outer ring can drive the elastic sleeve to move relative to the inner ring; the outer ring is used for fixing the sleeve and is arranged on the hub of the wheel, the inner ring is used for fixing the sleeve and is arranged on the axle, and the outer ring, the elastic sleeve, the inner ring, the hub of the wheel and the oil storage tank of the axle form the first cavity.

In the embodiment of the invention, the inner periphery of the wheel is provided with an internal spline, two ends of the axle are respectively provided with an external spline, and the wheel and two ends of the axle are connected in a matching way through the internal spline and the external spline; and an outlet of the first oil filling hole is positioned in a groove between two adjacent spline teeth of the internal spline.

In an embodiment of the invention, the first oil injection holes comprise a plurality of oil injection holes which are uniformly distributed on the circumference of the inner side surface of the wheel, and the first oil injection holes are obliquely arranged from the inner side surface of the wheel to the joint of the wheel and an axle.

In the embodiment of the invention, the inlets of the first oil filling hole, the second oil filling hole and the third oil filling hole are respectively provided with an internal thread section, and the inlets of the oil filling holes are sealed by screwing external thread fasteners on the corresponding internal thread sections.

Another embodiment of the present invention further provides a variable-gauge wheel set, which includes the lubricating structure for a variable-gauge wheel set according to the above technical solution.

(III) advantageous effects

Compared with the prior art, the invention has the following advantages:

the embodiment of the invention provides a lubricating structure for a track-variable wheel pair, which comprises wheels, an axle and a sliding mechanism, wherein the wheels are connected with the axle through a sliding mechanism; the wheels are slidably arranged at two ends of the axle, the sliding mechanisms are respectively connected to the outer sides of the wheels and are positioned in the axle box bodies at two ends of the axle, and the wheels are unlocked and locked through the sliding mechanisms; a sealing structure is arranged between the inner side of the wheel and the axle, a first cavity is formed between the inner side of the wheel and the axle as well as between the inner side of the wheel and the sealing structure, a second cavity is formed between the outer side of the wheel and the slip mechanism, and a third cavity is formed between the slip mechanism and the axle box body; the wheel is provided with a first oil hole leading to the joint of the wheel and an axle, the joint of the wheel and the axle is lubricated by injecting lubricating grease into the first oil hole, the lubricating grease is stored in the first cavity, the axle box body is provided with a second oil hole leading to the slipping mechanism, the part between the slipping mechanism and the axle box body is lubricated by injecting lubricating grease into the second oil hole, the part between the slipping mechanism and the axle box body is coated with lubricating grease, the part between the slipping mechanism and the axle is lubricated, and the lubricating grease is stored in the second cavity; under the condition that the wheels are not subjected to track change, lubricating grease is stored in the corresponding cavities, the sliding mechanism moves in the track change process of the wheels, the volumes of the cavities are changed, the lubricating grease can be extruded and flows, the friction surfaces are filled with the lubricating grease to form a lubricating layer, the lubricating layer plays a role in lubricating and protecting the friction surfaces, so that the abrasion of key parts which are easy to abrade is reduced, and the integral service life of the track-changing distance wheel pair is prolonged;

in addition, the first oil hole and the second oil hole are arranged so that maintenance and replenishment of lubricating grease can be carried out at any time.

Drawings

Fig. 1 is a partial axial cross-sectional view of a lubricating structure for a track-variable wheelset according to an embodiment of the invention;

FIG. 2 is a cross-sectional view of the axle housing in an embodiment of the present invention;

FIG. 3 is a schematic view of a wheel according to an embodiment of the present invention;

FIG. 4 is a cross-sectional view taken along line B-B of FIG. 3;

in the figure: 1: a wheel; 2: an axle; 3: an inner sleeve; 4: a rolling bearing; 5: an outer sleeve; 51: an axial through hole; 6: a sealing structure; 7: a first cavity; 8: a second cavity; 9: a third cavity; 10: a first oil filler hole; 11: a second oil filler hole; 12: a third oil filler hole; 13: the axle box body.

Detailed Description

The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood as appropriate by those of ordinary skill in the art.

In addition, in the description of the present invention, "a plurality", and "a plurality" mean two or more unless otherwise specified.

As shown in fig. 1, an embodiment of the present invention provides a lubricating structure for a track-variable wheel pair, which includes a wheel 1, an axle 2 and a slipping mechanism; the wheels 1 are slidably arranged at two ends of the axle 2, the sliding mechanisms are respectively connected to the outer sides of the wheels 1 and are positioned in axle box bodies 13 at two ends of the axle 2, and the wheels 1 are unlocked and locked through the sliding mechanisms; a sealing structure 6 is arranged between the inner side of the wheel 1 and the axle 2, a first cavity 7 is formed between the inner side of the wheel 1 and the axle 2 as well as between the sealing structure 6, a second cavity 8 is formed between the outer side of the wheel 1 and the sliding mechanism, and a third cavity 9 is formed between the sliding mechanism and the axle box body 13; as shown in fig. 3, a first oil filling hole 10 leading to the joint of the wheel 1 and the axle 2 is arranged on the wheel 1, when the track gauge of the wheel 1 is changed, the wheel 1 moves relative to the axle 2, a friction surface is arranged between the wheel 1 and the axle 2, the joint of the wheel 1 and the axle 2 is lubricated by injecting grease into the first oil filling hole 10, a lubricating layer is formed on the friction surface, and the grease is stored in the first cavity 7, as shown in fig. 2, a second oil filling hole 11 leading to the sliding mechanism is arranged on the axle box body 13; when the track gauge of the wheel 1 is changed, the sliding mechanism moves along with the wheel 1, moves relative to the axle box body 13 and forms a friction surface with the axle box body 13; lubricating between the skid gear and the axle box 13 by injecting grease into the second oil injection hole 11 to form a lubricating layer and storing the grease in the third cavity 9, moving the skid gear along the axle 2 when the wheel 1 moves, and similarly, having a friction surface between the skid gear and the axle 2, coating the grease at the position where the skid gear is matched with the axle 2, lubricating between the skid gear and the axle 2 to form a lubricating layer and storing the grease in the second cavity 8; under the condition that the wheel 1 is not in a track-changing state, lubricating grease is stored in the corresponding cavities, the sliding mechanism moves in the track-changing process of the wheel 1, the volume of each cavity is changed, the lubricating grease can be extruded to flow, the corresponding friction surfaces are filled with the lubricating grease to form a lubricating layer, the lubricating grease plays a role in lubricating and protecting the friction surfaces, the lubricating efficiency is favorably improved, the abrasion of key parts easy to abrade is reduced, and the overall service life of the track-changing distance wheel pair is prolonged.

In an embodiment of the present invention, specifically, the sliding mechanism includes an inner sleeve 3, the inner sleeve 3 is in clearance fit with the axle 2, one end of the inner sleeve 3 facing the wheel 1 extends out of the axle box 13 and is fastened to the wheel 1 through a fastener, and a track distance changing space is left between the extending end of the inner sleeve 3 and the axle 2 to ensure that the inner sleeve 3 has a sufficient distance to move along the axle 2 without interfering with the axle 2 when the track distance is changed, and the track distance changing space forms the second cavity 8; specifically, the axle 2 is provided with a stepped shaft with a middle diameter larger than diameters of two ends, the wheels 1 are arranged on a middle shaft of the stepped shaft and are respectively arranged at two ends of the middle shaft, and the sliding mechanisms are arranged on two end shafts of the stepped shaft; one end of the inner sleeve 3, which is connected with the wheel 1, is provided with an outward-expanding stepped hole, the inner diameter of a large hole of the stepped hole is matched with the outer diameter of an intermediate shaft of the stepped shaft, and the inner diameter of a small hole of the stepped hole is matched with the inner diameters of shafts at two ends of the stepped shaft; the track gauge changing space is reserved between the large hole of the stepped hole and the shaft shoulder of the stepped shaft to form the second cavity 8; before the sliding mechanism is installed, firstly, lubricating grease is coated on a corresponding section in the inner sleeve 3 or outside the axle 2, then the inner sleeve 3 is sleeved on the axle 2 and is connected with the wheel 1, the lubricating grease has certain fluidity, redundant lubricating grease is stored in the second cavity 8, the lubricating grease can be extruded and flowed in the process of changing the track pitch, the friction surface between the inner sleeve 3 and the axle 2 is filled, a lubricating layer is formed, and the effects of reducing friction and protecting the inner sleeve 3 and the axle 2 are achieved.

In the embodiment of the invention, the sliding mechanism further comprises a rolling bearing 4 and an outer sleeve 5, the inner sleeve 3, the rolling bearing 4 and the outer sleeve 5 are sequentially and tightly sleeved from inside to outside, when the wheel 1 rotates, the inner sleeve 3 and the inner ring of the rolling bearing 4 rotate together with the wheel 1, the outer sleeve 5 and the outer ring of the rolling bearing 4 are relatively fixed, and the outer sleeve 5 is in clearance fit with the inner surface of the axle box body 13, so that the outer sleeve 5, the inner sleeve 3 and the rolling bearing 4 integrally move along the axle box body 13; a space for the sliding mechanism to move is reserved between the outer end face of the outer sleeve 5 and the outer end cover of the shaft box body 13 to form the third cavity 9 for filling lubricating grease to lubricate between the outer sleeve 5 and the shaft box body 13.

In the embodiment of the invention, bosses extending along the axial direction of the outer sleeve 5 are respectively arranged on two opposite sides outside the outer sleeve 5, a plurality of grooves are arranged at intervals along the length direction of the bosses, the inner wall of the axle box body 13 is provided with concave arc surfaces corresponding to the grooves one by one, a locking pin is arranged in a locking space defined by the grooves and the concave arc surfaces of the axle box body 13, the locking pin is inserted into the locking space defined by the grooves and the concave arc surfaces, and the locking pin is switched among the locking spaces under the action of external force, so that the track gauge of the wheel 1 is changed. Specifically, when the locking pin is inserted into the locking space, one part of the locking pin is positioned in the groove, the other part of the locking pin is attached to the concave arc surface, the outer sleeve 5 is fixed relative to the axle box body 13 to realize locking, and at the moment, the wheel 1 is fixed relative to the axle 2; when the gauge is changed to needs, the fitting pin breaks away from the locking space at place under the exogenic action, realize the unblock, in this embodiment, preferably adopt ascending thrust to make the fitting pin break away from the locking space, at this moment, promote wheel 1 along axletree 2 outwards or inwards move, drive the sliding mechanism whole and remove for axletree box 13 and fitting pin along with it, when moving under the fitting pin with the corresponding locking space of the gauge change, the fitting pin inserts this locking space under the effect of self gravity and downward power, wheel 1 gauge change is accomplished. The axle box body 13 is further provided with a third oil filling hole 12 communicated with the concave cambered surface, so that lubricating grease can be conveniently filled into the concave cambered surface of the axle box body 13 from the third oil filling hole 12, the locking space where the locking pin is located is lubricated, and friction between the locking pin and the axle box body 13 and the outer sleeve 5 when the locking pin moves up and down is reduced.

In the embodiment of the present invention, as shown in fig. 2, in order to facilitate the arrangement of the third oil hole 12, the third oil hole 12 is arranged on the side wall of the axle box body 13 corresponding to the locking pin, and the grease injected from the third oil hole 12 can flow and cover the locking space between the whole concave cambered surface and the groove of the outer sleeve 5.

In the embodiment of the present invention, as shown in fig. 2, an axial through hole 51 slidably fitted with the outer sleeve 5 is provided in the shaft housing 13, and the second oil injection hole 11 is vertically provided from the top and/or bottom of the shaft housing 13 and is communicated with the axial through hole 51, so as to facilitate injecting grease from the top of the shaft housing 13 to lubricate between the shaft housing 13 and the outer sleeve 5, of course, grease may be injected from the bottom of the shaft housing 13 from bottom to top to lubricate between the shaft housing 13 and the outer sleeve 5, in order to fully cover the space between the shaft housing 13 and the outer sleeve 5, the second oil injection hole 11 may be provided at the top and bottom of the shaft housing 13, and in order to improve the injection efficiency, a plurality of second oil injection holes 11 may be provided at the top and bottom of the shaft housing 13 at the same time.

In the embodiment of the present invention, in order to facilitate storage of grease, an oil reservoir is provided in the radial direction of the axle 2 between the inner side of the wheel 1 and the seal structure 6, and the first cavity 7 is formed between the inner side of the wheel 1, the oil reservoir and the seal structure 6.

In an embodiment of the present invention, specifically, the sealing structure 6 includes an outer ring, an inner ring and an elastic sleeve, an inner diameter of the outer ring is greater than an outer diameter of the inner ring, one end of the elastic sleeve is fixedly connected to an inner circumference of the outer ring, the other end of the elastic sleeve is fixedly connected to an outer circumference of the inner ring, and the outer ring can drive the elastic sleeve to move relative to the inner ring; the outer ring is used for fixed cover to establish on wheel 1's wheel hub, the inner ring is used for fixed cover to establish on axletree 2, when becoming the gauge, the outer loop removes together with wheel 1, and the elastic sleeve utilizes the variability and the recoverability of its shape, follows the outer loop and removes together, and the inner ring is fixed, has solved the sealed problem of the relative slip in-process of wheel 1 and axletree 2 when becoming the gauge, the wheel hub of outer ring, elastic sleeve, inner ring, wheel 1 with form between axletree 2's the oil storage tank first cavity 7 through save lubricating grease in first cavity 7 to keep the continuous lubrication between wheel 1 and axletree 2, avoided because of the sealing member wearing and tearing that the relative movement produced between inner ring, the outer loop, and sealing performance is good, no leakage.

In the embodiment of the invention, the inner periphery of the wheel 1 is provided with an internal spline, two ends of the axle 2 are respectively provided with an external spline, and the wheel 1 and two ends of the axle 2 are in fit connection through the internal spline and the external spline, so that the torque transmission is facilitated, and the movement of the wheel 1 is also facilitated; the export of first oil filler point 10 is located in the recess between two adjacent spline teeth of internal spline to the storage after the grease is poured into, the formation of the lubricated layer of being convenient for when the spline meshes should avoid setting up first oil filler point 10 on the spline tooth of internal spline, weaken with the intensity that reduces first oil filler point 10 internal spline.

In the embodiment of the present invention, as shown in fig. 3, the first oil holes 10 comprise a plurality of oil holes 10, and the plurality of first oil holes 10 are uniformly distributed on the circumference of the inner side surface of the wheel 1, so that the first oil holes 10 having a proper angle are filled with grease no matter how the wheel 1 is parked, as shown in fig. 4, the first oil holes 10 are obliquely arranged from the inner side surface of the wheel 1 toward the connection between the wheel 1 and the axle 2, so that grease can flow into the connection between the wheel 1 and the axle 2 for lubrication.

In the embodiment of the invention, the inlets of the first oil filling hole 10, the second oil filling hole 11 and the third oil filling hole 12 are respectively provided with an internal thread section, and the inlets of the oil filling holes are sealed by screwing the external thread fasteners on the corresponding internal thread sections, so that lubricating grease is prevented from being thrown out of the oil filling holes when a vehicle runs at a high speed, and a reliable sealing effect is achieved. Through the arrangement of each oil hole, the maintenance and the supplement of lubricating grease can be conveniently carried out at any time.

Another embodiment of the present invention further provides a variable-gauge wheel set, which includes the lubricating structure for a variable-gauge wheel set according to the above technical solution. The abrasion of key wearing parts such as the part between the wheel 1 and the axle 2, the part between the inner sleeve 3 and the axle 2, the part between the outer sleeve 5 and the axle box body 13 and the like is reduced, so that the whole service life of the track-variable wheel pair is prolonged.

According to the embodiment, the lubricating grease is stored in the corresponding cavities, the sliding mechanism moves in the wheel track changing process, the volumes of the cavities are changed, the lubricating grease is extruded and flows to fill the friction surfaces, and the lubricating layer is formed to play a role in lubricating and protecting the friction surfaces, so that the abrasion of key parts easy to abrade is reduced, and the overall service life of the track-changing wheel pair is prolonged.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A lubricating structure for a track-variable wheel pair is characterized by comprising wheels, axles and a sliding mechanism; the wheels are slidably arranged at two ends of the axle, the sliding mechanisms are respectively connected to the outer sides of the wheels and are positioned in the axle box bodies at two ends of the axle, and the wheels are unlocked and locked through the sliding mechanisms; a sealing structure is arranged between the inner side of the wheel and the axle, a first cavity is formed between the inner side of the wheel and the axle as well as between the inner side of the wheel and the sealing structure, a second cavity is formed between the outer side of the wheel and the slip mechanism, and a third cavity is formed between the slip mechanism and the axle box body; the wheel is provided with a first oil filling hole leading to the joint of the wheel and the axle, lubricating the joint of the wheel and the axle by injecting lubricating grease into the first oil filling hole, and storing the lubricating grease in a first cavity; a second oil filling hole leading to the sliding mechanism is formed in the shaft box body, lubricating grease between the sliding mechanism and the shaft box body is lubricated by injecting lubricating grease into the second oil filling hole, and the lubricating grease is stored in a third cavity; the matching part of the sliding mechanism and the axle is coated with lubricating grease, the sliding mechanism and the axle are lubricated, and the lubricating grease is stored in the second cavity; the glide machanism includes the inner skleeve, the inner skleeve with axletree clearance fit, the inner skleeve orientation the one end of wheel extends the axle box body and with wheel fastening connection, the extension end of inner skleeve with leave the gauge transform space between the axletree, the gauge transform space forms the second cavity.

2. The lubricating structure for the track-variable wheel pair according to claim 1, wherein the sliding mechanism further comprises a rolling bearing and an outer sleeve, the inner sleeve, the rolling bearing and the outer sleeve are sequentially and tightly sleeved from inside to outside, and the outer sleeve is in clearance fit with the inner surface of the axle box body; and a third cavity is formed between the outer end surface of the outer sleeve and the outer end cover of the shaft box body.

3. The lubrication structure for the track-variable wheel pair according to claim 2, wherein bosses extending axially along the outer sleeve are respectively arranged on two opposite sides of the outer sleeve, a plurality of grooves are arranged at intervals along the length direction of the bosses, concave cambered surfaces corresponding to the grooves one to one are arranged on the inner wall of the axle box body, locking pins are arranged in locking spaces defined by the grooves and the concave cambered surfaces, and the axle box body is further provided with third oil filling holes communicated with the concave cambered surfaces.

4. The lubrication structure for track-variable wheel pair according to claim 3, wherein the third oil hole is provided in a side wall of the axle box body corresponding to the locking pin.

5. The lubrication structure for a track-variable wheel pair according to claim 2, wherein an axial through hole in sliding fit with the outer sleeve is formed in the axle box body, and the second oil injection hole is vertically formed from the top and/or the bottom of the axle box body and is communicated with the axial through hole.

6. The lubrication structure for a track-changing wheel pair according to claim 1, wherein an oil storage tank is radially provided on the axle between the inner side of the wheel and the sealing structure, and the first cavity is formed between the inner side of the wheel, the oil storage tank and the sealing structure.

7. The lubrication structure for the track-variable wheel pair according to claim 6, wherein the sealing structure comprises an outer ring, an inner ring and an elastic sleeve, the inner diameter of the outer ring is larger than the outer diameter of the inner ring, one end of the elastic sleeve is fixedly connected with the inner periphery of the outer ring, the other end of the elastic sleeve is fixedly connected with the outer periphery of the inner ring, and the outer ring can drive the elastic sleeve to move relative to the inner ring; the outer ring is used for fixing the sleeve and is arranged on the hub of the wheel, the inner ring is used for fixing the sleeve and is arranged on the axle, and the outer ring, the elastic sleeve, the inner ring, the hub of the wheel and the oil storage tank of the axle form the first cavity.

8. The lubrication structure for the track-variable wheel pair according to claim 1, wherein an inner circumference of the wheel is provided with an inner spline, both ends of the axle are respectively provided with an outer spline, and the wheel and both ends of the axle are connected with the outer splines through the inner splines in a matching manner; and an outlet of the first oil filling hole is positioned in a groove between two adjacent spline teeth of the internal spline.

9. The lubrication structure for a track-variable wheel pair according to claim 1, wherein the first oil injection holes comprise a plurality of first oil injection holes, the plurality of first oil injection holes are uniformly distributed in the circumferential direction of the inner side surface of the wheel, and the first oil injection holes are obliquely arranged from the inner side surface of the wheel toward the connection between the wheel and the axle.

10. The lubrication structure for track-variable wheel pair according to claim 3, wherein the inlets of the first oil filler hole, the second oil filler hole and the third oil filler hole are provided with an internal thread section, and the inlets of the oil filler holes are sealed by screwing an external thread fastener on the corresponding internal thread sections.

11. A variable-gauge wheelset characterized by comprising the lubricating structure for a variable-gauge wheelset according to any one of claims 1 to 10.