CN107600100B9

CN107600100B9 - Sliding assembly applied to variable-track-gauge bogie

Info

Publication number: CN107600100B9
Application number: CN201710780974.XA
Authority: CN
Inventors: 邵亚堂; 黄运华; 张隶新; 张云龙; 付茂海; 许红江; 刘东坡; 杜成义; 熊丽波
Original assignee: Southwest Jiaotong University; CRRC Tangshan Co Ltd
Current assignee: Southwest Jiaotong University; CRRC Tangshan Co Ltd
Priority date: 2017-09-01
Filing date: 2017-09-01
Publication date: 2023-07-28
Anticipated expiration: 2037-09-01
Also published as: CN107600100B; CN107600100A

Abstract

The invention belongs to the technical field of bogie systems, and particularly relates to a sliding component applied to a variable-track-gauge bogie, which comprises a sliding piece and an axle box; the sliding piece is a cylindrical body, and the outer side wall of the cylindrical body is axially and slidably connected with the axle box. The invention aims at: aiming at the problem of low transportation efficiency when a train passes through railways with different gauges, the sliding assembly is applied to the bogie, so that wheels can be axially adjusted relative to axles, and the wheel set wheel distance of the bogie is changed to adapt to railways with different gauges. Railway transportation of 'silk road economic zone' is developed, and the problem of non-uniform railway track gauge is faced. The most economical and effective method for solving the problem of non-uniform railway track gauge specification is to equip the train with a bogie with variable track gauge. Therefore, developing a design for a variable gauge bogie system is of great importance and significance.

Description

Sliding assembly applied to variable-track-gauge bogie

Technical Field

The invention belongs to the technical field of bogie systems, and particularly relates to a sliding component applied to a variable-track-gauge bogie.

Background

As business traffic for rail transportation continues to occur more frequently, international intermodal or regional intermodal channels are becoming more common, but for historical reasons, different gauge specifications are being adopted for railways in different countries and regions.

Currently, two alternatives exist for trains passing over railways of different gauge specifications. Firstly, a container transporting way, namely hoisting a container from a train with one gauge specification to a train with another gauge specification; and secondly, the bogie is replaced in a manner that the supporting device for the train is jacked up and suspended, and then the bogie with one gauge is dismounted and the bogie with the other gauge is mounted. These two modes of transportation are inefficient, which brings many limitations to the development of international intermodal transport.

Disclosure of Invention

The invention aims at: aiming at the problem of low transportation efficiency when a train passes through railways with different gauges, the sliding component applied to the variable-gauge bogie is provided, and the sliding component is applied to the bogie, so that wheels can be axially adjusted relative to axles, and the wheel set and the wheel distance of the bogie can be changed to adapt to railways with different gauges.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

A sliding assembly for a variable gauge bogie includes a slider and an axle housing; the sliding piece is a cylindrical body, the outer side wall of the cylindrical body is axially connected with the axle box in a sliding mode, and the outer side wall is provided with a limiting part used for limiting relative rotation between the outer side wall and the axle box. The outer side wall of the sliding piece and the axle box can axially and relatively slide; further, the outer side wall and the axle box cannot rotate relative to each other due to the restriction portion. So that the sliding piece and the axle box can move relatively axially and relatively fixedly circumferentially. Finally, the purposes that the bearing wheel integrated mounting seat, the wheel and the bearing can axially move relative to the axle box and the bearing and the axle box do not relatively rotate in the circumferential direction are achieved.

Preferably, the upper part of the sliding piece is elliptical, and the major axis of the ellipse is horizontal; the side wall of the axle box, which is contacted with the ellipse, is an ellipse matched with the axle box. The lock part unlocking stroke is too large to occupy the space of the axle box, so that the volume of the axle box is too large, and the installation and the matching of various devices of the bogie are affected. The sliding part has an oval outline, the long axis of the sliding part is horizontal, the sliding part can be unlocked by moving a smaller distance than a round shape, the unlocking stroke can be reduced, the vertical height is further reduced, the primary suspension and framework increasing height of the bogie is kept in a smaller range, and the train is adapted to the existing platform height. Meanwhile, as the protruding parts on two sides of the ellipse are unnecessary, a part of materials are cut off, thereby achieving the design requirement of light weight.

Preferably, two sides of the sliding piece are provided with protruding blocks serving as limiting parts, and the side walls of the axle boxes, which are contacted with the protruding blocks, are grooves matched with the protruding blocks. The two sides of the sliding piece are respectively provided with a lug for preventing the sliding piece from rotating relative to the axle box in the circumferential direction, and meanwhile, the inner wall of the axle box is provided with a groove matched with the lug.

Preferably, the projections are provided with mutually perpendicular planes. The mutually perpendicular planes of the projections ensure that the slider does not tend to rotate in the axle housing. If the axle box and the sliding piece are elliptical, the axle box and the sliding piece are easy to rotate and are clamped.

Preferably, the upper part of the outer side wall is provided with at least two rows of positioning grooves, and the axle box is provided with grooves matched with the positioning grooves. The locating grooves which are arranged on the upper portion of the outer side wall of the sliding piece and are on the same plane with the locking grooves on the two sides can be provided with a plurality of rows of locating grooves under the condition of various track gauge changes. The positioning groove plays a role in auxiliary locking and centering; the locking piece is prevented from sliding out of the lower end of the locking groove by the aid of the locking piece. Meanwhile, the axle box is provided with a space for the stroke of the positioning rod to ascend.

Preferably, the axle box and the sliding piece are in clearance fit. The clearance fit relationship can ensure that the two can axially and relatively slide.

Preferably, a skirt plate is further arranged below the axle box. The unlocking piece is arranged below the axle box, and the unlocking piece is easy to strike at any time on two sides of the track due to no shielding protection, so that the unlocking piece is damaged, and the apron board can effectively protect the unlocking piece.

In summary, due to the adoption of the technical scheme, compared with the prior art, the invention has the beneficial effects that: railway transportation of 'silk road economic zone' is developed, and the problem of non-uniform railway track gauge is faced. The most economical and effective method for solving the problem of non-uniform railway track gauge specification is to equip the train with a bogie with variable track gauge. The design scheme of the variable track bogie system is very important and has far-reaching significance. Compared with the traditional bogie with fixed track gauge, the bogie wheels can be axially adjusted relative to the axles when the train bogie passes through railways with different track gauges by the scheme, so that the wheel set track gauge of the bogie is changed to adapt to railways with different track gauges. The transportation mode has extremely high efficiency, saves operation and brings great convenience for developing international intermodal transportation.

Drawings

Fig. 1 is a perspective view of an axle, fig. 2 is a cross-sectional view of the axle, fig. 3 is a perspective view of a bearing wheel integrated mount, fig. 4 is a cross-sectional view of the bearing wheel integrated mount, fig. 5 is a perspective view of an axle assembly, and fig. 6 is a front view of the axle assembly.

Fig. 7 is a perspective view of the slider, fig. 8 is a front view of the slider, fig. 9 is a side view of the slider, fig. 10 is a top view of the slider, fig. 11 is a perspective view of the lock member, fig. 12 is a front view of the lock member, fig. 13 is a perspective view of the unlock member first, fig. 14 is a front view of the unlock member, and fig. 15 is a perspective view of the unlock member second.

Fig. 16 is a perspective view of an axle box assembly, fig. 17 is a perspective view of an upper axle box, fig. 18 is a perspective view of a lower axle box, fig. 19 is a perspective view of a lower axle box, fig. 20 is a cross-sectional perspective view of an axle box, fig. 21 is a cross-sectional front view of an axle box, fig. 22 is a perspective view of a skirt board, and fig. 23 is a perspective view of a skirt board.

Fig. 24 is a cross-sectional perspective view of the first slide assembly, fig. 25 is a cross-sectional perspective view of the second slide assembly, fig. 26 is a side view of the first lock assembly, fig. 27 is a side view of the second lock assembly, fig. 28 is a side view of the third lock assembly, fig. 29 is a perspective view of the first lock assembly, fig. 30 is a perspective view of the second lock assembly, fig. 31 is a perspective view of the third lock assembly, fig. 32 is a perspective view of the fourth lock assembly, fig. 33 is a perspective view of the fifth lock assembly, fig. 34 is a front view of the key assembly, fig. 35 is a perspective view of the key assembly, fig. 36 is a cross-sectional perspective view of the first slide key assembly, fig. 37 is a cross-sectional perspective view of the second slide key assembly, fig. 38 is a cross-sectional perspective view of the third slide key assembly, fig. 39 is a cross-sectional perspective view of the fourth slide key assembly, and fig. 40 is a cross-sectional perspective view of the fifth slide key assembly.

Fig. 41 is a perspective view of the support unlocking rail, fig. 42 is a side view of the support unlocking rail, fig. 43 is a sectional view A-A of the support unlocking rail, fig. 44 is a perspective view of the gauge conversion device, fig. 45 is a plan view of the gauge conversion device, fig. 46 is a schematic diagram of a plan positional relationship of the gauge conversion device, and fig. 47 is a schematic diagram of a front view positional relationship of the gauge conversion device.

Fig. 48 is a cross-sectional perspective view of the wheel set, fig. 49 is a side view of the wheel set, fig. 50 is a C-C cross-sectional view of the wheel set first, fig. 51 is a C-C cross-sectional view of the wheel set second, fig. 52 is a front cross-sectional view of the wheel set, and fig. 53 is a D-D cross-sectional view of the wheel set.

The names of the corresponding parts in the drawings are:

an A-axle assembly; a1-an axle, A11-a movable pair connecting part, A12-a shoulder, A13-an end cap and A14-a gear box mounting seat; the device comprises an A2-bearing wheel integrated mounting seat, an A21-bearing mounting seat, an A22-wheel mounting seat, an A23-moving pair joint part, an A24-shaft shoulder and an A25-stop nut.

B-a sliding key assembly; the device comprises a B1-sliding piece, a B11-outer side wall, a B12-inner side wall, a B13-locking groove, a B14-unlocking groove, a B15-positioning groove, a B16-lug and a B17-end cover; b2-locking piece, B21-locking rod, B22-locking piece, B23-positioning rod; the device comprises a B3-unlocking piece, a B31-underframe, a B32-return spring, a B33-tray, a B34-buffer plate and a B35-roller.

C-axlebox assembly, C1-axlebox, C2-bearing, C3-apron.

D-track gauge conversion device, D1-sleeper; d2-track; the device comprises a D3-supporting rail, a 31-supporting table, a 32-supporting front section, a 33-supporting middle section, a 34-supporting rear section, a 35-baffle, 36-rollers, a D31-supporting preparation rail and a D32-supporting continuous rail; d4-unlocking rail, 41-unlocking front section, 42-unlocking middle section, 43-unlocking rear section, D41-unlocking preparation rail and D42-unlocking continuous rail; d5—guide rail; d6-clamping rail, D61-clamping section, D62-bell mouth section; a-supporting section, a '-supporting buffer section, b-unlocking section, b' -unlocking buffer section and c-guiding section.

F-wheels.

Detailed Description

The present invention will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.

Taking a CRH 2-type motor train unit truck as an example, the following examples are based on improvements made by existing CRH 2-type motor train unit trucks. The supporting facilities such as the H-shaped framework, the axle box suspension device, the secondary suspension device and the like are the same as the corresponding equipment in the existing CRH2 motor train unit bogie, so that the description is omitted. The following detailed description is now made only with respect to improvements of the present invention over existing CRH2 motor train unit bogies.

Example 1

A slider assembly for use with a variable gauge bogie, as shown in fig. 25, comprising a slider B1 and an axle housing C1; the sliding piece B1 is a cylindrical body, an outer side wall B11 of the cylindrical body is axially connected with the axle box C1 in a sliding manner, and a limiting part for limiting relative rotation between the outer side wall B11 and the axle box C1 is arranged on the outer side wall B11.

The upper part of the sliding piece B1 is elliptical, and the major axis of the ellipse is horizontal; the side wall of the axle box C1, which is in contact with the oval shape, is an oval shape matched with the axle box C1. Two sides of the sliding piece B1 are provided with a lug B16 serving as a limiting part, and the side wall of the axle box C1, which is contacted with the lug B16, is provided with a groove matched with the axle box C. The bumps B16 are provided with mutually perpendicular planes. At least two rows of positioning grooves B15 are formed in the upper portion of the outer side wall B11, and grooves matched with the shaft boxes C1 are formed in the shaft boxes. The axle box C1 and the sliding piece B1 are in clearance fit. An apron board C3 is also arranged below the axle box C1.

The following describes in detail the improvement of the present embodiment with respect to the prior art: axle assembly a, sliding key assembly B, axle housing assembly C, and associated gauge change-over device D.

As shown in fig. 1-2, the wheel seat to end position of the axle A1 is a movable pair connecting part a11, and the freedom direction of the movable pair is the same as the axial direction of the main body of the axle A1. Turning off a layer of material from the two ends of the axle A1 to the wheel seat positionsNamely, the sub-moving connecting portion a11 is formed. The inner end of the sliding pair connecting part A11 is provided with a shoulder A12. The axle A1 is provided with a gear box mounting seat a14. The axle A1 is a hollow shaft. End caps A13 are arranged at the two ends of the opening of the hollow shaft. Prototype hollow axle inner diameterIn order to ensure that the axle A1 has sufficient strength, the axle A1 after modification has a hollow inner diameter of +.>

As shown in fig. 3-4, the bearing wheel integrated mounting seat A2 is a cylindrical body, the bearing mounting seat a21 and the wheel mounting seat a22 are arranged outside the cylindrical body, the hollow part of the cylindrical body is a moving pair joint part a23, and the freedom degree direction of the moving pair joint part a23 is the same as the axial direction of the axle A1. The outer surface profile of the bearing wheel integrated mounting seat A2 is consistent with the profile of the power axle of the prototype vehicle,outer diameter of the mounting bearingBased on the power wheel set of the CRH2 motor train unit bogie, the wheels of the prototype vehicle are kept +.>Hub hole->The isoparametric is unchanged and the wheel F does not need any modification. The wheel F is matched with the wheel mounting seat A22 in an interference mode, a shaft shoulder A24 for stopping the hub of the wheel F is machined at the outer side end part of the wheel mounting seat A22, and looseness can be prevented when the wheel F axially slides. The outer end of the bearing mounting seat a21 is provided with an external thread for mounting the stop nut a 25. The wheel F, the bearing sealing ring, the sealed double-row tapered roller bearing C2, the oil seal ring, the end stop nut A25 and the like are arranged outside the bearing wheel integrated mounting seat A2.

Axle assembly A, as shown in FIGS. 5-6, includes an axle A1 and a bearing wheel integral mount A2; the moving pair joint part A23 is sleeved on the moving pair connecting part A11, and the moving pair joint part A23 and the moving pair connecting part A11 form an axial moving pair. The moving pair joint portion a23 is a cylindrical hollow portion; the movable pair connecting portion a11 is a cylinder, and a generatrix of the cylinder is the same as an axial direction of the axle A1 main body. The side wall of the moving pair joint part A23 is provided with an axial convex spline; the side wall of the movable pair connecting part A11 is provided with matched axial concave splines. The sliding pair joint portion a23 and the sliding pair connecting portion a11 are in clearance fit relation. The sliding pair connecting portion a11, the bearing mount a21, the wheel mount a22, and the sliding pair engaging portion a23 overlap with the axis of the axle A1 main body. With sleeve outside the axle, i.e. with sleeve inner diameterThe outer surface of turning position at two sides of the axle>The spline is processed on the position, and the spline is also designed on the inner wall of the sleeve to be matched with the sleeve, so that the torque can be transmitted while the axial sliding is ensured.

7-10, the sliding piece B1 is a cylindrical body, two rows of locking grooves B13 are processed on the side surface of the outer side wall B11 of the sliding piece B1, the direction of the locking grooves B13 is perpendicular to the axial direction, and the sliding piece B1 is in a vertical state when being installed on a bogie. An unlocking groove B14 is formed between the locking grooves B13, the unlocking grooves B14 are used for mutually communicating two adjacent rows of locking grooves B13, the direction of the unlocking grooves B14 coincides with the axial direction, and two unlocking grooves B14 are formed. Two rows of positioning grooves B15 are formed in the upper portion of the outer side wall B11, and the direction of the positioning grooves B15 is perpendicular to the axial direction. The upper portion of the outer side wall B11 is elliptical, and the major axis of the ellipse is horizontal. The cross section of the positioning groove B15 is semicircular or semi-elliptic. The two sides of the outer side wall B11 are provided with the convex blocks B16, and the convex blocks B16 comprise planes which are perpendicular to each other. The outer ring of the bearing C2 is sleeved with the sliding part B1, and then end covers B17 are arranged at two ends of the sliding part B1 through 4M 16 bolts distributed circumferentially, so that the whole bearing C2 is packaged in the sliding part B1, and the end covers B17 are positioned at the inner circle part and are recessed inwards.

The sliding part B1 adopts an inner circle and outer circle elliptical shape, the inner circle is used for assembling the bearing C2, two sides of the elliptical long axis are cut off to form two vertical planes, a convex block B16 used for limiting the sliding part B1 to rotate in the axle box C1 is designed on the vertical planes, two U-shaped notches used for locking are formed in the convex block B16, namely locking grooves B13 (the axial distance is determined according to the requirement of the changed track gauge), the U-shaped notches are used for track gauge change between the standard track gauge (1435 mm) and the wide track (1520 mm), and meanwhile, two rows of grooves, namely positioning grooves B15, are formed in corresponding positions on the outer surface of the ellipse of the sliding part B1 and are respectively located on the same plane with the locking grooves B13. The bottom of the positioning groove B15 is semicircular or semi-elliptic. Inner side wall of sliding part B1The bearing outer ring is used for being matched and installed. The outer side wall B11 is designed into an ellipse, the shape of the end cover B17 is the same as the outline of the sliding part B1, and the end cover B17 is hollow +.>Can be used for the installation of the axle assembly A.

The locking piece B2, as shown in figures 11-12, comprises a lock rod B21 and a lock block B22; the locking block B22 is positioned in the axle box C1 and connected to the upper part of the locking rod B21 and used for locking the locking groove B13 on the sliding piece B1; the lower part of the axle box C1 is provided with a round hole, and the lock rod B21 is inserted into the round hole and is connected with the axle box C1 in a sliding way, and the lower part of the lock rod B21 extends out of the axle box C1 from the axle box C1. The locking piece B2 further comprises two positioning rods B23, the two locking rods B21 are oppositely arranged, and two ends of each positioning rod B23 are respectively connected with the upper end of each locking rod B21 to form an inverted U-shape. The locking block B22 mainly plays a role in locking; the positioning rod B23 mainly plays a role in auxiliary centering and guiding, and simultaneously, the two side locking rods B21 are connected into a whole. The edge line of the lower part of the locking block B22 is provided with a corner cutting structure. The section of the lock rod B21 is circular and is matched with the round hole of the axle box C1. The lower end of the lock lever B21 is provided with a screw hole for mounting the unlocking member B3. The positioning rod B23 is elliptical, and the major axis of the ellipse is horizontal and matches with the outer side wall B11 of the slider B1. The section of the lower part of the positioning rod B23 is semicircular or semi-elliptic and is matched with the positioning groove B15.

The upper part of each lock rod B21 is provided with at least two lock blocks B22, when the lock blocks are unlocked with the unlocking grooves B14 of the sliding piece B1, the lock blocks B22 are mutually matched in a sectional dislocation unlocking mode, the unlocking stroke is controlled to be in the range of 30-40mm, and when the ascending stroke exceeds 30mm, the two lock blocks B22 on the lock rod B11 are aligned with the two unlocking grooves B14 on the side face of the sliding piece B1, and the lock blocks can be unlocked to axially move. The locking piece B11 is cylindrical, so that the processing is convenient, and the locking piece B can be matched with a cylindrical hole of the axle box C1 reliably.

The unlocking piece B3, as shown in fig. 13-15, comprises a bottom frame B31, and the bottom frame B31 is V-shaped. The tray B33 is provided with screw holes. The two ends of the underframe B31 are provided with buffer plates B34, the buffer plates B34 are elastic flat plates, and the plane where the flat plates are positioned is horizontal. The bottom of the chassis B31 is provided with a roller B35. The outer side of the rim of the roller B35 is made of elastic materials.

The underframe B31 is fixedly connected with the locking piece B21 through a long screw M8x25GB/T65-2000, a roller shaft and a roller B35 are arranged at the bottom of the underframe B31, and the locking piece B2 is pushed to move vertically upwards through the action of an unlocking rail so as to be separated from the locking groove B13 of the sliding piece B1 and aligned with the unlocking groove B14, so that the axial movement unlocking is realized. When in locking, the locking piece B2 returns along with the descending of the unlocking rail height through the automatic resetting of the resetting spring B23 arranged at the underframe.

Key assembly b2+b3, as shown in fig. 34-35, includes lock B2 and unlock B3; the locking piece B2 comprises a locking rod B21; the lock rod B21 is in sliding connection with the axle box C1, the upper part of the lock rod B21 is positioned in the axle box C1, and the lower part of the lock rod B21 extends out of the axle box C1 from the axle box C1; the unlocking piece B3 comprises a bottom frame B31, and two ends of the bottom frame B31 are respectively connected with the lower end of the lock rod B21.

Two ends of the underframe B31 are provided with a tray B33 for stopping a return spring B32, a lock rod B21 passes through the return spring B32 to be connected with the tray B33, and the return spring B32 is positioned between the axle box C1 and the tray B33. The locking piece B2 further comprises a positioning rod B23, and two ends of the positioning rod B23 are respectively connected with the upper end of the locking rod B21 to form an inverted U shape. The positioning rod B23 enters the positioning groove B15 to form a block, and is matched with the return spring B32, so that the lifting and the descending of the locking piece B2 are limited. Screw holes matched with each other are arranged on the tray B33 and the lower end of the lock rod B21, and the tray B33 and the lock rod B21 are connected through bolts.

A locking assembly B1+ B2, as shown in fig. 26-33, comprising a slider B1 and a locking member B2; the locking block B22 of the locking member B2 is connected to the upper portion of the locking bar B21, and cooperates with the two rows of locking grooves B13 of the outer sidewall B11 of the slider B1. The lock lever B21 and the unlock groove B14 are provided in a right-left direction and in a left direction in a matching manner. The two sides of the sliding piece B1 are symmetrically locked, the key points of the two sides are strengthened, the stress is even, the contact area is larger during locking, and the locking effect is better. An unlocking groove B14 for the locking block B22 to pass through is arranged between the locking grooves B13, and the unlocking grooves B14 mutually communicate two adjacent rows of locking grooves B13. The U-shaped locking piece B2 is separated from the positioning groove B15, so that unlocking can be realized. The width of the lock block B22 is smaller than the width of the unlocking groove B15. Two rows of positioning grooves B15 are formed in the upper portion of the outer side wall B11; the two ends of the positioning rod B23 of the locking piece B2 are respectively connected with the upper ends of the two locking rods B21. Not only the two sides are completely locked, but also the upper part is used for assisting in locking and centering, so that the axial shearing force can be more uniformly born, and the reliability is higher.

The positioning rod B23 and the positioning groove B15 are mutually matched ellipses, if the external shape is designed into a round shape, the top end position of the semicircular positioning rod B23 is far away from the positioning groove B15, but the two sides are not separated, and separation unlocking can be realized only through a larger ascending stroke. On the other hand, the lock block B22 and the unlock groove B14 are provided two by two in match with each other. Because of the limitation of the lifting space, if the locking piece B22 is designed as a whole, the locking piece B22 needs to lift by a large stroke to be separated and unlocked, and then the dome-shaped groove of the top of the axle box C1 for accommodating the positioning rod B23 needs to be designed deeper, which finally results in a heavy axle box C1. The axle box C1 is larger and more severe than the prototype vehicle, and the frame body mounted thereon will rise from the rail surface, causing a series of inadaptation, and more parts will be needed to be changed. Therefore, the lock bars B21 are provided with a plurality of lock blocks B22 at intervals, and the lock blocks B22 are lifted up one by one to cooperate with a plurality of unlocking grooves B14, so that the lifting stroke of the lock blocks B22 is greatly shortened, and the axle box C1 is not affected, even the structural layout of the whole bogie is not affected.

When the track gauge is changed, the wheel F, the bearing sealing ring and the sliding piece B1 can axially slide along with the bearing wheel integrated mounting seat A2, and when the proper track gauge position is reached, the sliding piece B1 is locked by the locking piece B2, so that the axial movement of the bearing wheel integrated mounting seat A2 and the wheel F can be fixed. Specifically, fig. 26 and 29 show a state where the lock member B2 and the slider B2 are locked to each other, and at this time, the lock piece B22 is positioned in the lock groove B13, and the positioning lever B23 is positioned in the positioning groove B15. Fig. 27 and 30 show the unlocked state, in which the lock block B22 is disengaged from the lock groove B13 and aligned with the unlock groove B14, and the positioning lever B23 is disengaged from the positioning groove B15. Fig. 28 and 31 show an unlocking process in which the slider B1 and the lock B1 are axially slidable relative to each other. Fig. 32 is a state of relatively sliding to the other locking groove B13. Fig. 33 is a state in which the lock member B2 and the slider B2 are locked again to each other.

The axle box assembly C, as shown in fig. 16-23, is mainly improved with respect to the inner wall structure and the overall size of the axle box C1, and is improved with respect to the adaptability of other parts. Further, a skirt plate C3 for protecting the unlocking piece B3 is also installed at the bottom of the axle box C1.

Specifically, the embodiment adopts a positioning mode of a pivoted axle box, the axle box C1 adopts an up-down split type design, and a bolt mounting seat is designed on the outer surface of the box through bolt fixed connection. Fig. 17 is an inside of the upper case, fig. 18 is an upper portion of the lower case, and fig. 19 is a lower portion of the lower case. This prevents the problem of the internal locking groove and the circular hole not being machined due to the integral casting. Meanwhile, the split design can ensure the correct installation of the locking piece B2, namely, the locking piece B2 is firstly arranged in an arch notch of the upper box body, the lower box body is installed in a closed mode, the locking piece B11 penetrates into a circular hole of the lower box body, and the bottom frame B31 of the unlocking piece B3 extends out from the bottom and is assembled through a screw. The design of the axle box front cover only ensures that the axle box can be accurately installed on the modified axle box, so the design of the axle box front cover needs to be matched with the axle box. The radial size of the axle box is increased when the rotating arm type axle box is designed, the inner diameter of the axle box C1 is designed to be consistent with the outer side wall B11 of the sliding piece B1, the axle box is a vertical plane with an elliptical upper surface, an elliptical lower surface and two sides, and grooves are processed on the vertical plane and are used for being matched with the bumps of the sliding piece B1. Because of the enlarged overall size, the original primary vertical shock absorber seat needs to be designed in a lengthening way so as to prevent the interference between the vertical shock absorber cylinder body and the axle box. The rotating arm type positioning node is not affected, so that the positioning node does not need to be modified.

As shown in fig. 20 and 21, an elliptical groove and a circular hole are formed on the symmetrical center plane of the axle box C1 for mounting the locking member B2 and locking with the locking groove B13 and the positioning groove B15 of the slider B1. The arch groove is 35mm deep, and comprises 15mm that retaining member B2 half stretches into slider B1 constant head tank when locking, half stretches into axle box arch groove, and 20mm of upstroke when unblock.

In order to prevent the impact of severe environmental factors and stone sundries during operation, as shown in fig. 22 and 23, a skirtboard C3 is designed at the position of installing an unlocking member B3 at the lower part of the axle box, and is in a square frame shape, a middle groove is used for extending out of a roller of a locking member, and two side planes are used for bearing surfaces borne by the axle box. In order to ensure enough strength and support the weight of the whole bogie, rib plates are machined on the inner frame of the apron board.

A slider assembly B1+ C1, as shown in fig. 24-25, comprising a slider B1 and an axle housing C1; the outer side wall B11 of the sliding piece B1 is axially and slidably connected with the axle box C1; the outer side wall B11 is provided with a regulating portion for regulating relative rotation between the outer side wall B11 and the axlebox C1.

The slider B1 and the axle box C1 have matching elliptical shapes. The two sides of the slider B1 are provided with a projection B16 as a restricting portion, and the side wall of the axle box C1 in contact with the projection B16 is a groove matching therewith. The bumps B16 are provided with mutually perpendicular planes. The axle box C1 is provided with a groove matching the positioning groove B15 for accommodating the ascending stroke of the positioning rod B23. The axle box C1 and the slider B1 are in clearance fit. An apron board C3 is also provided below the axle box C1.

The outer side wall B11 of the cylindrical body is axially and slidably connected with the axle box C1, and the inner side wall B12 is axially and fixedly connected with the bearing mounting seat A21 through the bearing C2. The bearing C2 adopts a sealed double-row tapered roller bearing, and is a standard bearing of the high-speed motor train unitAn intermediate ring is arranged in the middle of the inner ring, and oil sealing rings are arranged at two ends of the inner ring and used for sealing grease. After the sliding part B1 is press-fitted into the bearing mounting seat a21 with the bearing C2 by interference, the stopper nut a25 assists the stopper on the outside, and the other end of the sliding part B1 is additionally restrained from axial movement by the bearing seal ring.

36-40, the gage transformation assembly B1+B2+C1 includes a slider B1, a lock B2, and an axle housing C1; the outer side wall B11 of the sliding piece B1 is axially and slidably connected with the axle box C1; the locking block B22 of the locking piece B2 is positioned in the axle box C1 and is matched with the locking groove B13; the lock rod B21 is in sliding connection with the axle box C1, and the lower part of the lock rod B extends out of the axle box C1; both ends of the underframe B31 of the unlocking piece B3 are respectively connected with the lower end of the lock rod B21.

The U-shaped that locating lever B23 and locking lever B21 on retaining member B2 upper portion formed is unanimous with axle box C1 oval notch, and when cooperation slider B1 locking, locating lever B23 stretches into in the constant head tank B15, and the upper half cooperates with axle box C1 arch notch, and both sides locking piece B22 card is advanced locking groove B13 to bear axial shear through retaining member B2, retrain the axial displacement of rocking arm formula axle box C1 and slider B1, and then guarantee that corresponding gauge position is unchangeable.

The axlebox C1 remains relatively stationary in the bogie system during the track gauge change. The matched sliding piece B1 and the locking piece B2 move relatively to achieve the aim of changing the track gauge. Specifically, fig. 36 shows a locked state in which the lock piece B22 is positioned in the lock groove B13 and the positioning lever B23 is positioned in the positioning groove B15. Fig. 37 shows the unlocking process, in which the lock lever B21 is pushed by the unlocking piece B3 to move upward, the lock piece B22 is disengaged from the lock groove B13, and the positioning lever B23 is disengaged from the positioning groove B15. Fig. 38 shows the track gauge change process, at which the slider B1 is slid relatively with respect to the axlebox C1 until the other lock groove B13, i.e., the state shown in fig. 39. Fig. 40 is a view of the condition of reaching another gage position and being again locked.

The support unlocking rail D3D4 comprises a support rail D3, as shown in fig. 41-43, wherein the upper part of the support rail D3 is a support table 31, and the support table 31 is also provided with the unlocking rail D4. The front end of the support midsection 33 is located forward of the unlocking front section 41. The rear end of the support midsection 33 is located rearward of the unlocking rear section 43. When the track gauge of the track-changing bogie is changed, an axle box bearing mode is adopted, and the track-changing process operates more stably, so that the axle box bearing mode is adopted. The axle box bearing mode is adopted, and the corresponding support rail and unlocking rail can be integrally designed, namely, a groove is formed in the middle of the support rail and used as the unlocking rail D4. The whole is composed of a supporting and supporting table 31, a cylindrical roller bearing, an axle box outer baffle 35, an intermediate unlocking groove (unlocking rail D4) and the like. The whole device is a rectangular boss and is arranged below the track outer axle box C1, so that the complicated ground track gauge conversion device is simplified.

The support rail D3 is provided below the axlebox C1. Rollers 36 are provided on the top surface of the support table 31 or on the inner side surface of the baffle 35. The roller conveyor is in contact with the axle box by rolling friction. The roller 36 is provided with cylindrical roller bearings, code 32206E, of size d×d×b=Φ30×Φ62×16, extending from both ends of the cylindrical roller. The outer ring of the cylindrical roller bearing is fixed and does not rotate, and the inner ring rotates to drive the roller to rotate. The upper surface of the cylindrical roller is 5mm higher than the boss seat, so that only the cylindrical roller is contacted with the lower bottom surface of the axle box C1 during bearing, and the whole bogie is made to advance through the rolling of the cylindrical roller.

The support table 31 includes a support front section 32, a support middle section 33, and a support rear section 34 connected in order, the support front section 32 being an ascending surface, the support middle section 33 being a flat surface, the support rear section 34 being a descending surface. The supporting rail D3 serves to make the train bogie first switch the loading mode when entering the ground gauge switching device, and to suspend the wheels F for unloading by switching the weight carried by the wheels to the axlebox C1, i.e., the axlebox loading mode. Therefore, in the design of the support rail D3, in order to ensure that the axle box C1 can smoothly slide on the support table 31, the initial positions at both ends of the support rail are processed into an inclined shape, so that the support rail D3 can reliably lift the axle box assembly C when the bogie enters the rail F-distance conversion device.

The unlocking rail D4 includes an unlocking front section 41, an unlocking middle section 42 and an unlocking rear section 43 which are sequentially connected, the unlocking front section 41 is an ascending surface, the unlocking middle section 42 is a flat surface, and the unlocking rear section 43 is a descending surface. The unlocking rail D4 has a top surface lower than the top surface of the supporting table 31 to form a groove structure. A rectangular groove is designed in the middle of the support rail D3 and is used as an unlocking rail D4, and the groove is divided into three sections: the lifting slope section, the horizontal section and the descending slope section are respectively used for realizing the functions of unlocking, keeping the unlocking state and locking. Both ends of the groove structure are open. The two ends of the unlocking groove D4 are designed into circular arc inclined planes, so that the cleaning of sewage and dirt is facilitated after the unlocking groove is cleaned or sundries fall into the groove. The unlocking inclined plane of the unlocking rail D4 can enable the locking mechanism to vertically ascend for 40mm of travel, and the sliding piece B1 and the locking piece B2 are guaranteed to be separated.

The outside of the support table 31 is provided with a baffle 35, and the top surface of the baffle 35 is higher than the top surface of the support table 31. The baffles 35 are in contact with the outer side surface of the axle box C1, and the axle box C1 is clamped by the baffles 35 on both sides, so that the left-right swing and serpentine motion of the wheels when lifted and moved forward can be prevented, and the guide centering effect is achieved.

44-47, the track gauge conversion device D comprises a support rail D3, an unlocking rail D4 and a guide rail D5, wherein the support rail D3 comprises a support preparation rail D31 and a support continuous rail D32, and the unlocking rail D4 comprises an unlocking preparation rail D41 and an unlocking continuous rail D42; the support preparation rail D31 forms a support section a; the support continuous rail D32 and the unlocking preparation rail D41 form an unlocking section b; the support continuation rail D32, the unlocking continuation rail D42 and the guide rail D5 form a guide section c. A supporting buffer section a 'is arranged between the supporting section a and the unlocking section b, and the supporting buffer section a' is composed of a supporting continuous rail D32. An unlocking buffer section b 'is arranged between the unlocking section b and the guiding section c, and the unlocking buffer section b' is composed of a supporting continuous rail D32 and an unlocking continuous rail D42.

The track D2 is composed of a track straight section D21 and a track descending section D22, and the track descending section D22 is located inside the supporting section a. Because the new wheel and the old wheel have the problem that the axle box C1 moves downwards due to the fact that the height is lowered after abrasion, the initial end of the supporting rail D3 is designed to be inclined, and meanwhile, the rail D2 is also designed to be slightly inclined downwards when entering the gauge conversion device, so that the axle box is assisted to bear the load, and the wheels are suspended.

Take the example of a 1435mm gage region to 1520mm gage region transition. The wheel guide rail D5 is in a clamping shape, and the middle axial distance between the two guide rails D5 at the rail D2 is 135mm according to the requirement of the width of the wheel rim of the motor train unit. The guide rail D5 is arranged in the gauge change section, and since the bogie is carried by the axlebox C1, the track D2 is not provided in the middle thereof, and the 1435mm gauge track and 1520mm gauge track are connected only at the guide rail start and end transition sections. In order to ensure that the wheels can be aligned when the wheels are about to enter the guide rail, the two ends of the guide rail are further provided with clamping rails D6, the clamping rails D6 comprise clamping sections D61, one ends of the clamping sections D61 are connected with the guide rail D5, and the other ends of the clamping sections extend to rail straight sections D21. The clamping rail D6 further comprises a flare section D62, the flare section D62 being connected to an end of the clamping section D61.

The variable gauge bogie a+b+c, as shown in fig. 48-53, includes an axle assembly a, a sliding key assembly B, and an axle box assembly C; the moving pair joint part A23 and the moving pair connecting part A11 of the axle assembly A form an axial moving pair, and the wheel F is mounted on the wheel mounting seat A22; the outer side wall B11 of the sliding piece B1 of the sliding key assembly B is axially and slidably connected with the axle box C1, and the inner side wall B12 is axially and fixedly connected with the bearing mounting seat A21 through the bearing C2. The locking block B22 of the locking piece B2 of the sliding key assembly B is positioned in the axle box C1, is connected to the upper part of the locking rod B21 and is matched with the locking groove B13 of the sliding piece B1; the lock rod B21 is in sliding connection with the axle box C1, and the lower part of the lock rod B extends out of the axle box C1; are respectively connected with two ends of the underframe B31 of the unlocking piece B3; the bottom of the chassis B31 is provided with a roller B35. The apron board C3 of the axle box assembly C is arranged below the axle box C1; the lower part of the apron board C3 is provided with a through hole, and the roller B35 extends out of the apron board C3 through the through hole.

The variable-track-gauge bogie adopts the mode that the wheel F and the bearing C2 move together with the bearing wheel integrated mounting seat A2, and the sliding piece B1 is locked, so that the axial fixation of the wheel F is achieved, and the requirements of track gauge conversion of different track gauges are met. Based on the CRH2 bogie, the bogie is applicable after being modified in a small range; but also to other types of bogies.

According to the scheme, the bearing mounting seat and the wheel mounting seat are integrally arranged, and the wheel and the bearing are respectively installed on the wheel mounting seat and the bearing mounting seat in an interference mode. Meanwhile, the bearing mounting seat and the wheel mounting seat are arranged on the movable pair joint part, and the bearing and wheel integrated mounting seat is arranged on the movable pair connecting part of the axle, so that the movement of the wheel can be controlled by controlling the position of the bearing on the bearing and wheel integrated mounting seat in the axle box assembly, and the axial movement problem of the wheel during track gauge change is further realized. The axle assembly is provided with a movable pair connecting part and a movable pair joint part which can axially slide, so that only the wheel, the bearing wheel integrated mounting seat and the bearing can be moved when the track gauge is changed. A sliding piece is additionally arranged between the bearing and the axle box, the outer side wall of the sliding piece is in clearance fit with the axle box, and the sliding piece and the axle box can axially and relatively slide; further, the outer side wall and the axle box cannot rotate relative to each other due to the restriction portion. The inner side wall of the sliding piece is in interference fit with the bearing outer ring, and the bearing inner ring is in interference fit with a bearing mounting seat of the bearing wheel integrated mounting seat. Thereby the bearing wheel is axially fixed relative to the sliding part and can rotate relative to the sliding part; the sliding piece and the axle box can move relatively axially, and are fixed relatively circumferentially. The positions of the axle main body and the axle box, the primary suspension and other devices are kept unchanged, so that the relative stability and safety of the track gauge conversion process are improved. In addition, the axial moving pair can slide back and forth to reach the positions of different gauges, and can be designed into the conversion between two gauges and the conversion between three or more gauges according to the requirements of specific gauge conversion specifications, so that the axle assembly has a very wide application range. Finally, the purposes that the bearing wheel integrated mounting seat, the wheel and the bearing can axially move relative to the axle box and the bearing and the axle box do not relatively rotate in the circumferential direction are achieved.

The locking groove can realize that the wheels are locked by matching the locking groove with the locking block when moving to different track gauge positions. The locking piece is fixed on the locking rod, and when the locking rod ascends, the locking piece is driven to ascend together, so that the locking piece is separated from the locking grooves on two sides of the sliding piece and enters the unlocking groove. Otherwise, when the lock rod descends, the lock block is driven to descend together, so that the lock block is separated from unlocking grooves on two sides of the sliding piece and enters the locking groove. The above process realizes the conversion from the locking state to the unlocking state. And locking grooves with various track gauge positions can be arranged at the two side positions of the outer side wall according to the track gauge specification. The direction of the locking groove is preferably perpendicular to the axial direction, so that a good locking effect can be achieved. The corresponding locking piece and unlocking piece are matched, and the vertical direction is preferable. And the groove-shaped locking mode has simple structure and reliable performance.

The locking groove positions on two sides are provided with axial unlocking grooves, when the locking rod of the locking piece is lifted upwards by a certain height, the locking piece enters the unlocking groove area, the sliding piece can axially move, and when the sliding piece moves to the other locking groove, the locking piece descends and enters the other locking groove from the unlocking groove area to complete locking. The mode that the locking piece was crisscrossed gets into axial unlocking groove when rising can set up a plurality ofly in the condition that vertical space is sufficient, is the rectangle cusp, and corresponding unlocking groove can also set up a plurality ofly, combines or separates each other with the rectangle cusp. The lock blocks are staggered to enter the unlocking groove area, and unlocking lifting travel can be reduced in a cross locking and unlocking mode. At the same time, too many locking blocks are not desirable to ensure a sufficient locking contact surface.

The locating grooves which are arranged on the upper portion of the outer side wall of the sliding piece and are on the same plane with the locking grooves on the two sides can be provided with a plurality of rows of locating grooves under the condition of various track gauge changes. The positioning groove plays a role in auxiliary locking and centering; the locking piece is prevented from sliding out of the lower end of the locking groove by the aid of the locking piece. Meanwhile, the axle box is provided with a space for the stroke of the positioning rod to ascend.

The lock part unlocking stroke is too large to occupy the space of the axle box, so that the volume of the axle box is too large, and the installation and the matching of various devices of the bogie are affected. The sliding part has an oval outline, the long axis of the sliding part is horizontal, the sliding part can be unlocked by moving a smaller distance than a round shape, the unlocking stroke can be reduced, the vertical height is further reduced, the primary suspension and framework increasing height of the bogie is kept in a smaller range, and the train is adapted to the existing platform height. Meanwhile, as the protruding parts on two sides of the ellipse are unnecessary, a part of materials are cut off, thereby achieving the design requirement of light weight.

The upper portion of the underframe is connected with the lock rod, the V-shaped underframe can be lifted by the stress of the lowest point in the middle, so that the left locking rod and the right locking rod ascend with cloth and are synchronously unlocked, and the problems are completely avoided. The roller at the lower end of the V-shaped underframe realizes the effect that sliding friction on the inclined plane of the unlocking rail is changed into rolling friction. The roller rolls on the inclined plane of the unlocking rail and lifts the V-shaped underframe upwards, so that the effect is more ideal.

The unlocking piece is arranged below the axle box, and the unlocking piece is easy to strike at any time on two sides of the track due to no shielding protection, so that the unlocking piece is damaged, and the apron board can effectively protect the unlocking piece.

The track gauge conversion method A+B+C+D comprises the following steps: supporting the bogie to unload the wheels; step ii, unlocking the sliding piece to enable the wheels to be free; and iii, sliding the wheel to enable the wheel to become a track.

The supporting bogie in step i adopts an axle box supporting mode. The support of the axlebox is achieved by means of a support rail mounted on the track bed, which is arranged below the axlebox.

In the step ii), the wheels are free, namely, the bearing mounting seat and the wheel mounting seat are integrally arranged to form a bearing wheel integral mounting seat, and the bearing wheel integral mounting seat and the axle are separately arranged and can axially and relatively slide. In the step ii), the wheels are in a locking state before unlocking, and the locking mode is that a sliding part is arranged between the axle box and the bearing, a locking part is arranged between the sliding part and the axle box, and locking is realized through the locking part. In the step ii), the wheels are unlocked in a mode that an unlocking piece is arranged below the axle box and connected with the locking piece, and the locking piece is driven by the unlocking piece to unlock. Unlocking is achieved through an unlocking rail arranged on the track bed, and the unlocking rail is arranged below the unlocking piece.

In step iii, the sliding wheel adopts a guide rail sliding mode. The sliding of the wheels is realized through the guide rail arranged on the track bed, and the two ends of the guide rail are respectively connected with the track.

Taking the transformation process of changing the wheel track gauge from 1435mm standard track position to 1520mm wide track position as an example, the track gauge transformation process of the track gauge variable bogie is described, and the working principle thereof is as follows:

(1) When the wheels reach the ground track gauge conversion device, the supporting rail is contacted with the apron board below the pivoted axle box, and the bogie is lifted to unload the wheels.

(2) The unlocking rail inclined surface at the middle groove of the supporting rail rises to push the roller to overcome the resistance of the reset spring and vertically move upwards, so that the U-shaped locking piece is pushed to move upwards to be separated from the sliding piece positioning groove, and the sliding piece and the bearing wheel are separated from the integrated mounting seat, so that the wheel is unlocked.

(3) Then, the wheels move outwards under the action of the ground wheel guide rail, and the bearing wheel integrated mounting seat and the sliding piece integrated with the wheels are driven to slide together. So far, the disc brake is also unlocked. The wheel drives the bearing wheel to axially slide together with the wheel integrated mounting seat, the sliding piece and the wheel disc braking device. The wheel gauge is changed from the quasi-rail position (1435 mm) to the wide rail position (1520 mm).

(4) When the required track gauge is reached, the inclined plane of the unlocking track at the middle groove of the supporting track descends, and the locking mechanism moves vertically downwards under the action of the reset spring. At the moment, the U-shaped locking piece slowly enters the sliding piece positioning groove through the oval groove of the axle box, and locking blocks at two sides also extend into the locking groove, so that the sliding piece is locked, the axial movement of the bearing wheel integrated mounting seat and the wheel is limited, and finally the wide rail position is achieved.

When the wheel tread is narrowed from wide, the whole transformation process is basically the same as that described above, and only the wheels need to move in the opposite direction. Simultaneously, the wheel disc braking device capable of automatically locking also moves in the opposite direction.

The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.

Claims

1. A slip assembly for a variable gauge bogie, characterized by: comprises a sliding piece (B1) and an axle box (C1); the sliding piece (B1) is a cylindrical body, an outer side wall (B11) of the cylindrical body is axially connected with the axle box (C1) in a sliding mode, and a limiting part used for limiting relative rotation between the outer side wall (B11) and the axle box (C1) is arranged on the outer side wall (B11);

At least two rows of positioning grooves (B15) are formed in the upper part of the outer side wall (B11), and grooves matched with the shaft boxes (C1) are formed in the shaft boxes;

two rows of locking grooves (B13) are formed in the side face of the outer side wall (B11) of the sliding piece (B1); a locking member (B2) comprising a lock rod (B21) and a lock block (B22); the locking piece (B22) is positioned in the axle box (C1) and connected to the upper part of the locking rod (B21) and used for locking the locking groove (B13) on the sliding piece (B1); the lower part of the axle box (C1) is provided with a round hole, the lock rod (B21) is inserted into the round hole and is in sliding connection with the axle box (C1), and the lower part of the lock rod (B21) extends out of the axle box (C1) from the axle box (C1); the locking piece (B2) further comprises two positioning rods (B23), the two locking rods (B21) are oppositely arranged, and two ends of each positioning rod (B23) are respectively connected with the upper end of each locking rod (B21) to form an inverted U shape;

two ends of a bottom frame (B31) of the unlocking piece (B3) are respectively connected with the lower end of the locking rod (B21);

the U-shaped formed by the positioning rod (B23) and the locking rod (B21) at the upper part of the locking piece (B2) is consistent with the oval notch of the axle box (C1), when the locking piece (B1) is matched for locking, the positioning rod (B23) stretches into the positioning groove (B15), the upper half part of the positioning rod is matched with the arched notch of the axle box (C1), and the locking blocks (B22) at two sides are clamped into the locking groove (B13);

The axleboxes (C1) remain relatively fixed in the bogie system during the track gauge change; the sliding piece (B1) and the locking piece (B2) matched with the sliding piece are moved relatively to achieve the aim of changing the track gauge, when in a locking state, the locking piece (B22) is positioned in the locking groove (B13), and the positioning rod (B23) is positioned in the positioning groove (B15); when the lock is unlocked, the lock rod (B21) is pushed by the unlocking piece (B3) to move upwards, the lock block (B22) is separated from the locking groove (B13), and the positioning rod (B23) is separated from the positioning groove (B15); when the track gauge is changed, the sliding piece (B1) slides relatively to the axle box (C1) until the other locking groove (B13) reaches the other track gauge position and is locked again.

2. The skid assembly for a variable gauge bogie of claim 1, wherein: the upper part of the sliding piece (B1) is elliptical, and the long axis of the ellipse is horizontal; the side wall of the axle box (C1) contacted with the ellipse is an ellipse matched with the axle box.

3. The skid assembly for a variable gauge bogie of claim 1, wherein: two sides of the sliding piece (B1) are provided with protruding blocks (B16), and the side wall of the axle box (C1) contacted with the protruding blocks (B16) is a groove matched with the side wall.

4. A skid assembly for a variable gauge bogie as set forth in claim 3 wherein: the projections (B16) are provided with mutually perpendicular planes.

5. The skid assembly for a variable gauge bogie of claim 1, wherein: the axle box (C1) and the sliding piece (B1) are in clearance fit.

6. The skid assembly for a variable gauge bogie of claim 1, wherein: and a skirt board (C3) is arranged below the axle box (C1).