Anti-rollover wheel pair of portable rail car and rail car

Abstract

The utility model relates to the technical field of rail cars, in particular to a light rail car rollover prevention wheel pair and a rail car, which comprises a wheel main body, a wheel flange part, a connecting shaft and an elastic limiting component, the circumferential wall face of the wheel body is a tread used for making contact with the top face of a rail. The circumferential diameter of the rim part is larger than the maximum diameter of the tread, and the end face of the rim part is used for abutting against the side wall of the track. Wherein the wheel main body is fixedly connected with the connecting shaft, and the rim part is slidably connected with the connecting shaft; wherein an abutting hole is formed in the center of the rim part, the connecting shaft is provided with a spherical surface structure, and the abutting hole is connected with the connecting shaft in a sleeved mode; the elastic limiting assembly enables the abutting hole to abut against the spherical surface structure and limits the rotating angle of the wheel flange part around the sphere center of the spherical surface structure. According to the wheel, the rim and the tread are arranged in a split mode, the rim does not need to be excessively far away from a rail, and therefore the rim can conduct intervention in the initial stage of deflection of a vehicle, and the vehicle is prevented from rolling over to a greater extent.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of rail car, especially a portable rail car anti-rollover wheel pair and rail car. BACKGROUND

[0002] Rail car refers to all conveying tools running on the track, from high-speed rail to handcart, the rail car referred to in the application is a small car capable of carrying people to drive at low speed on the railway track.

[0003] The wheel of the rail car is mainly responsible for contacting the track with the rim and the tread, the tread is responsible for rolling, and the rim is located between the two tracks and maintains a certain distance with the side wall surface of the track, which generally does not contact the track, and plays a limiting role when the rail car is deflected to prevent the wheel from leaving the track.

[0004] The rim is the main structure to prevent the rail car from rolling over, but the distance between the rim and the track is large, and the rim can only intervene when the vehicle is deflected by a large amplitude, but the larger the deflection amplitude of the center of gravity of the vehicle, the more difficult it is to correct the vehicle, and the larger the force required for correction. Thus, the anti-rollover effect of the rim on the wide-spaced track is not ideal. SUMMARY

[0005] To solve the above-mentioned prior art problems, the utility model provides a portable rail car anti-rollover wheel pair, which comprises a wheel body, a rim part, a connecting shaft and an elastic limiting assembly.

[0006] The circumferential wall surface of the wheel body is a tread for contacting the top surface of the track.

[0007] The circumferential diameter of the rim part is greater than the maximum diameter of the tread, and the end surface of the rim part is used to abut against the side wall of the track.

[0008] The wheel body is fixedly connected with the connecting shaft, and the rim part is slidingly connected with the connecting shaft.

[0009] The rim part has an abutting hole at the center, the connecting shaft has a spherical surface structure, and the abutting hole is sleeved with the connecting shaft.

[0010] The elastic limiting assembly makes the abutting hole abut against the spherical surface structure and limits the angle of rotation of the rim part around the center of the spherical surface structure.

[0011] Further, the elastic limiting assembly has a compression spring.

[0012] One end of the compression spring abuts against the end surface of the rim part.

[0013] The other end of the compression spring is fixedly connected to the connecting shaft.

[0014] Furthermore, the elastic limiting component has a limiting sleeve, which is fixedly disposed in the connecting shaft;

[0015] The limiting sleeve surrounds the circumferential region of the compression spring;

[0016] The end of the limiting sleeve near the rim is the first end, which is used to limit the swing amplitude of the rim.

[0017] Furthermore, a bearing assembly is provided between the compression spring and the wheel rim, and the compression spring abuts against the bearing assembly to allow relative rotation between the compression spring and the wheel rim.

[0018] Furthermore, the bearing assembly includes an end cap and a bearing;

[0019] The inner or outer ring of the bearing is fixedly connected to the rim portion;

[0020] The end cap is fixedly connected to the inner or outer ring of the bearing, and the end face of the end cap abuts against the compression spring.

[0021] Furthermore, the abutment hole has a conical abutment surface.

[0022] Furthermore, the travel distance from the first end to the part abutting the rim is L1; the travel distance from the wheel body to the part abutting the rim is L2;

[0023] L1 < L2.

[0024] Furthermore, the outer surface of the wheel body is covered with a protective layer made of polyurethane.

[0025] Furthermore, the protective layer of the wheel body has multiple anti-slip textures, each of which forms a circle around the axis of the wheel body.

[0026] Furthermore, a railcar, including the lightweight railcar anti-rollover wheelset described in the above-mentioned item, is characterized in that it includes a body and a drive unit;

[0027] The drive unit is fixedly installed in the vehicle body;

[0028] The driving device is connected to the connecting shaft and drives the connecting shaft to rotate.

[0029] The beneficial effects of the utility model lie in that the wheel rim and the tread of the wheel are set in a split body mode, the wheel rim does not need to be excessively far away from the track, so that the wheel rim can intervene in the initial stage of the vehicle deflection, and the vehicle is prevented from entering a larger degree of rollover. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 A cross-sectional structure schematic view of the light rail car anti-rollover wheel set provided by the utility model;

[0031] Figure 2 A cross-sectional structure schematic view of the light rail car anti-rollover wheel set provided by the utility model under the gravity deflection state of the center of gravity;

[0032] Figure 3 A Figure 1 A local enlarged schematic view of a in the middle;

[0033] Figure 4 A Figure 2 A local enlarged schematic view of b in the middle;

[0034] Figure 5 A three-dimensional structure schematic view of the light rail car anti-rollover wheel set provided by the utility model;

[0035] Figure 6 A three-dimensional structure schematic view of the light rail car anti-rollover wheel set provided by the utility model arranged in the track;

[0036] Figure 7 A schematic view of the rail car provided by the utility model.

[0037] Reference signs: 1, wheel body; 11, tread; 12, protective layer; 121, anti-skid texture; 2, wheel rim part; 21, abutting hole; 3, connecting shaft; 31, spherical surface structure; 4, elastic limiting assembly; 41, compression spring; 42, limiting sleeve; 5, bearing assembly; 51, end cover; 52, bearing; 6, track; 7, vehicle body; 71, driving device. DETAILED DESCRIPTION

[0038] Clearly, the described embodiments are merely a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0039] Embodiment 1

[0040] With reference to Figures 1-6 .

[0041] A portable rail car anti-rollover wheel set, comprising a wheel body 1, a rim portion 2, a connecting shaft 3 and an elastic limiting assembly 4.

[0042] The circumferential wall surface of the wheel body 1 is a tread surface 11 for contacting the top surface of a rail 6.

[0043] The circumferential diameter of the rim portion 2 is greater than the maximum diameter of the tread surface 11, and the end surface of the rim portion 2 is used to abut the side wall of the rail 6.

[0044] The wheel body 1 is fixedly connected with the connecting shaft 3, and the rim portion 2 is slidingly connected with the connecting shaft 3.

[0045] The rim portion 2 has an abutting hole 21 at the center, the connecting shaft 3 has a spherical surface structure 31, and the abutting hole 21 is sleeved with the connecting shaft 3.

[0046] The elastic limiting assembly 4 is used to abut the abutting hole 21 with the spherical surface structure 31, and limit the angle of rotation of the rim portion 2 around the spherical center of the spherical surface structure 31.

[0047] For those small track cars used for railway inspection and observation, the bottom of the track car and the supporting area of the track 6 are small, and the center of gravity is high after the staff sits on it, which is unstable when the track car turns and prone to rollover. In the prior art, the wheel position of such track cars has a certain rollover prevention design. Specifically, the wheel is different from the conventional automobile tire structure, but presents a circular truncated cone structure, the circumferential wall surface of the circular truncated cone is called the tread 11, which directly contacts the top surface of the track 6, and the left and right wheels are arranged in the two tracks 6 respectively. Since the circumferential wall surface of the circular truncated cone is a slope, when the tread 11 is above the top surface of the track 6, a part of the vertical force will be decomposed into a force towards the two tracks 6, so that the track car always remains in the track 6. At the same time, the wheel also has a rim, which is a circle of blocking protrusions protruding along the circumferential wall surface of the circular truncated cone, and the rim is located at the bottom surface of the circular truncated cone. The outer diameter of the rim is larger than the diameter of the bottom surface of the circular truncated cone. When the wheel deviates, the end surface of the rim will abut against the side wall of the track 6, further preventing the vehicle from rolling over through the abutment of the two.

[0048] However, for the wheel with an integral structure of the rim and the wheel body 1, the distance between the end surfaces of the left and right rims must be less than the minimum distance between the two tracks 6 to avoid the tracks 6 blocking the two wheels. This leads to the fact that when the wheel faces a wider track 6, the rim can only intervene in the rollover of the vehicle after the vehicle has a large degree of deviation, but the greater the deviation of the center of gravity of the vehicle, the more difficult it is to correct the vehicle, and the greater the force required to correct the vehicle. This leads to the fact that the rim has poor rollover prevention effect when facing a wide-interval track 6.

[0049] To solve the above problems, the application provides a wheel that can effectively prevent the track car from rolling over in a wider track 6.

[0050] Specifically including wheel body 1 and rim 2, the wheel of the application splits the part of the tread 11 and the part of the rim in the prior art wheel into two parts. The wheel body 1 and the rim 2 are connected through the connecting shaft 3, which can be an independent shaft or one end of the transmission shaft connecting the left and right wheels of the rail vehicle. The connecting shaft 3 is connected to the driving device 71, and the wheel body 1 is directly fixed in the connecting shaft 3, which rotates to drive the wheel body 1 to rotate, so that the rail vehicle can run normally. The connecting shaft 3 has a spherical surface structure 31, which can be a semicircular part with a through hole, and the axis of the through hole is perpendicular to the end face of the semicircle. The connecting shaft 3 passes through the through hole, and a protrusion can be arranged in the connecting shaft 3 to abut against the end face of the hemisphere to limit the sliding of the spherical surface structure 31. The spherical surface structure 31 can also be formed by turning directly when producing the connecting shaft 3. The rim 2 is provided with an abutting hole 21 in the center, and the connecting shaft 3 passes through the abutting hole 21. It should be noted that the connecting shaft 3 and the abutting hole 21 are not shaft hole matched, and in the application, there is a large gap between the two, allowing the rim 2 to have a certain degree of swing freedom. At the same time, the connecting shaft 3 is also provided with an elastic limiting component 4, which applies a spring force to the rim 2 towards the spherical surface structure 31, so that the abutting hole 21 abuts against the spherical surface of the spherical surface structure 31. At this time, when the lower part of the rim 2 is subjected to a force parallel to the axis direction of the connecting shaft 3, the rim 2 will rotate around a straight line passing through the center of the spherical surface structure 31 and perpendicular to the connecting shaft 3 in a plane located in the longitudinal section of the track 6 (this action is called rim 2 swing).

[0051] Further, the abutting hole 21 can be further provided with a conical abutting surface at the chamfer position of the regular circular hole edge. The conical abutting surface can better fit the spherical surface, and the abutting surface can smoothly slide in the spherical surface.

[0052] The elastic limiting component 4 is provided with an elastic member, which can be a spring piece, a compression spring 41, a tension spring, etc. The elastic member is preferably a compression spring 41. One end of the compression spring 41 is fixed in the connecting shaft 3, and the other end abuts against the rim 2. The compression spring 41 not only has an axial extension and contraction amount, but also can swing towards the circumferential direction, which can adapt to the swing of the rim 2.

[0053] Further, the elastic limiting component 4 has a limiting sleeve 42, which is fixedly arranged in the connecting shaft 3.

[0054] The limiting sleeve 42 surrounds the circumferential area of the compression spring 41 to prevent the compression spring 41 from being bent too much.

[0055] The wheel rim 2 has a certain activity space in the application to avoid the track 6 from clamping the wheel, which causes the vehicle to be unable to normally travel, but the wheel rim 2 cannot move at will, and the function of the wheel rim 2 in preventing rollover mainly depends on the abutment of the wheel rim 2 against the side wall of the track 6. If the wheel rim 2 continuously avoids, the maximum force that the wheel rim 2 can provide will be equal to the elastic force of the compression spring 41. However, the elastic force of the compression spring 41 cannot be set too large in the vehicle, and if the elastic force of the compression spring 41 is too large, the wheel is still prone to clamping when passing through a relatively narrow track 6, and there is no difference from the wheel with an integral wheel rim. In the initial stage of the vehicle rollover, the inclination of the gravity center is small, and it is relatively easy to correct, the wheel rim 2 abuts against the side wall of the track 6 and squeezes the compression spring 41, at this time the elastic force provided by the spring deformation is the force for correcting the vehicle, which is sufficient to correct the vehicle in the case of slight rollover. When this part of the elastic force is not enough to correct the vehicle, the gravity center of the vehicle will continue to tilt, further compressing the compression spring 41, until the wheel rim 2 abuts against the limiting sleeve 42. Referring to Figure 2 At this time, the wheel rim 2 will not be able to continue to avoid, and the limiting sleeve 42 and the wheel rim 2 can withstand the maximum force, which is the force that can provide the vehicle with the function of preventing rollover, at this time the effect of the wheel of the application in preventing rollover is basically the same as that of the wheel with an integral wheel rim.

[0056] Further, referring to Figure 3 The end of the limiting sleeve 42 close to the wheel rim 2 is the first end, and the stroke of the first end to abut against the wheel rim 2 is L1; the stroke of the wheel body 1 to abut against the wheel rim 2 is L2;

[0057] L1 < L2.

[0058] The limiting sleeve 42 and the wheel body 1 are respectively located on both sides of the wheel rim 2, when one end of the wheel rim 2 inclines towards the limiting sleeve 42, the other end will incline towards the wheel body 1. If L1 > L2, the wheel rim 2 will abut against the wheel body 1, and the wheel rim 2 abutting against the wheel body 1 can indeed play a role in limiting the swing of the wheel rim 2, but the axis of the wheel rim 2 after swinging is not coaxial with the axis of the wheel body 1, which leads to the fact that the two cannot rotate synchronously, and therefore the two will rub against each other, causing wear and affecting the rotation of the wheel body 1.

[0059] Therefore, in the embodiment, L1 < L2 is set, so that the wheel rim 2 only abuts against the limiting sleeve 42 and will not contact the wheel body 1, avoiding the intervention of the wheel rim 2 in the rotation of the wheel body 1.

[0060] Wherein, L1 and L2 are the lengths of the strokes, rather than the distances between the wheel rim 2 and the first end or the wheel body 1. The wheel rim 2 performs swinging rather than translation, so L1 and L2 are actually an arc length.

[0061] When the track vehicle runs to the narrower track 6, the side wall of the track 6 abuts against the end face of the flange part 2, at this time the flange part 2 swings to avoid the track 6, compared with the wheel in which the wheel body 1 and the flange part 2 are integrally arranged, the abutting force between the flange part 2 and the track 6 can be greatly reduced, so that the track vehicle can normally pass through the road section with small track 6 spacing, which makes the wheel of the application be able to intervene in the initial stage of vehicle deflection, and prevent the vehicle from entering a larger degree of rollover. At the same time, even if the elastic force provided by the elastic limiting assembly 4 is not enough to cope with the initial rollover of the vehicle, the elastic limiting assembly 4 can also fix the flange part 2 through the rigid abutting structure, so that the flange part 2 can provide abutting force which is not weaker than that provided by the integral flange, thereby greatly reducing the risk of vehicle rollover.

[0062] Embodiment 2

[0063] Reference Figures 1-4 .

[0064] The compression spring 41 and the flange part 2 are provided with a bearing assembly 5, and the compression spring 41 abuts against the bearing assembly 5 to enable relative rotation between the compression spring 41 and the flange part 2.

[0065] The spring has a spiral direction, and if the spring is twisted in the reverse direction of the spiral direction, it is easy to cause plastic deformation of the spring and damage the spring. The track vehicle can run in two directions, that is, the wheel can be forward or reversed, which causes the compression spring 41 and the flange part 2 to rotate in the reverse direction of the spiral direction. Especially when the flange part 2 abuts against the track 6, the friction between the flange part 2 and the compression spring 41 is large, and it is very easy to cause the compression spring 41 to be over-tightened, resulting in damage to the compression spring 41.

[0066] To this end, the bearing assembly 5 is arranged between the flange part 2 and the compression spring 41 in the embodiment, and the friction between the two is reduced by the bearing assembly 5, greatly reducing the torque acting on the compression spring 41 around the axis.

[0067] The bearing assembly 5 comprises an end cover 51 and a bearing 52.

[0068] The inner ring or outer ring of the bearing 52 is fixedly connected with the flange part 2.

[0069] The end cover 51 is fixedly connected with the inner ring or outer ring of the bearing 52, and the end face of the end cover 51 abuts against the compression spring 41.

[0070] For example, the outer ring of the bearing 52 is embedded with the wheel rim 2, and then the end cover 51 is embedded in the inner ring of the bearing 52, so that the pressure between the compression spring 41 and the wheel rim 2 is transmitted through the bearing assembly 5, but the bearing assembly 5 can convert the sliding friction between the compression spring 41 and the wheel rim 2 into rolling friction, thereby reducing the stress on the compression spring 41.

[0071] Embodiment 3

[0072] With reference to Figure 1 And 2 .

[0073] The outer part of the wheel body 1 is wrapped with a protective layer 12 made of polyurethane material.

[0074] Vehicle jolt is also an important reason for vehicle rollover. As a high-elasticity material, polyurethane can effectively absorb the impact and vibration when the wheel and rail contact, thereby reducing the jolt of the vehicle. It can prevent the vehicle from rolling over during the vibration bounce. The elastic deformation capability of the polyurethane layer can increase the wheel and rail contact area, and the increased contact area between the wheel and the rail 6 can also effectively prevent the vehicle from rolling over and derailing. In addition, polyurethane has a high friction coefficient, which can provide better wheel and rail contact adhesion, especially in wet, rainy or muddy environments to prevent skidding.

[0075] Further, the protective layer 12 of the wheel body 1 has a plurality of anti-skid textures 121, each of which forms a circle around the axis of the wheel body 1.

[0076] The anti-skid texture 121 in the present embodiment is not the same as the anti-skid texture 121 of a common wheel. The anti-skid texture 121 in a general tire mainly increases the friction between the tire and the ground in the rolling direction to prevent the tire from slipping and causing the tire to spin.

[0077] The anti-skid texture 121 in the present embodiment is a circle around the axis of the wheel body 1, and when viewed in the cross-sectional direction of the rail 6, the anti-skid texture 121 is perpendicular to the width direction of the rail 6. That is, the anti-skid texture 121 in the present embodiment mainly plays a role in preventing the wheel body 1 from slipping in the width direction of the rail 6. The derailment of the rail car during rollover is necessarily the wheel body 1 shifting towards one of the rail 6, and the vehicle further tilting with the rail 6 as the fulcrum.

[0078] The anti-skid texture 121 in the present application is to increase the difficulty of the initial shift of the rail car, thereby preventing the vehicle from rolling over.

[0079] Further, the wheel rim 2 can be provided with a wear-resistant layer made of wear-resistant material.

[0080] Embodiment 4

[0081] With reference toFigures 1-7 .

[0082] A rail car, comprising a light rail car anti-rollover wheel set according to any one of the preceding embodiments, characterized in that it comprises a car body 7, a driving device 71;

[0083] The driving device 71 is fixedly arranged in the car body 7;

[0084] The driving device 71 is connected with the connecting shaft 3 to drive the connecting shaft 3 to rotate.

[0085] In the description of the embodiments of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "center", "top", "bottom", "top", "bottom", "inner", "outer", "inner side", "outer side" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. Among them, "inside" refers to the inside or enclosed area or space. "Periphery" refers to the area around a particular component or a particular area.

[0086] In the description of the embodiments of the present application, the terms "first", "second", "third", "fourth" are only used for description purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features limited by "first", "second", "third", "fourth" can be explicitly or implicitly included one or more features. In the description of the present application, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0087] In the description of the embodiments of the present application, it should be noted that unless otherwise specified and limited, the terms "mounting", "connecting", "connecting", "assembling" should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be directly connected, or indirectly connected through an intermediate medium; it can be the communication between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0088] In the description of the embodiments of the present application, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0089] In the description of the embodiments of the utility model, need understanding, "-" and "~" indicate two numerical range of same, and the range includes end point. For example: "A-B" indicates greater than or equal to A, and less than or equal to the range of B. "A ~ B" indicates greater than or equal to A, and less than or equal to the range of B.

[0090] In the description of the embodiments of the utility model, the term "and / or" in this paper is only a kind of description associated relationship of associated object, it indicates that there can be three kinds of relations, for example, A and / or B, can indicate: exist A alone, exist A and B simultaneously, exist B alone these three cases.In addition, the character " / " in this paper generally indicates that the associated object before and after is a kind of "or" relation.

[0091] Although the embodiments of the utility model have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the utility model, and the scope of the utility model is defined by the appended claims and their equivalents.

Claims

1. A portable railcar roll-prevention wheelset, comprising: The wheel body, the rim part, the connecting shaft and the elastic limiting assembly are included. The circumferential wall surface of the wheel body is a tread surface for contacting a top surface of a track. The circumferential diameter of the rim part is greater than the maximum diameter of the tread surface, and the end surface of the rim part is used for abutting against a side wall of the track. The wheel body is fixedly connected with the connecting shaft, and the rim part is slidingly connected with the connecting shaft. The rim part has an abutting hole in the center, the connecting shaft has a spherical surface structure, and the abutting hole is sleeved with the connecting shaft. The elastic limiting assembly makes the abutting hole abut against the spherical surface structure and limits the angle of rotation of the rim part around the spherical center of the spherical surface structure.

2. The anti-rollover wheel set for a light rail vehicle according to claim 1, wherein The elastic limiting assembly has a compression spring. One end of the compression spring abuts against the end surface of the rim part. The other end of the compression spring is fixedly connected with the connecting shaft.

3. The anti-rollover wheel set for a light rail vehicle according to claim 2, wherein The elastic limiting assembly has a limiting sleeve, and the limiting sleeve is fixedly arranged in the connecting shaft. The limiting sleeve surrounds the circumferential area of the compression spring. The end of the limiting sleeve close to the rim part is a first end, and the first end is used for limiting the swing amplitude of the rim part.

4. The anti-rollover wheel set for a light rail vehicle according to claim 3, wherein A bearing assembly is arranged between the compression spring and the rim part, and the compression spring abuts against the bearing assembly to enable relative rotation between the compression spring and the rim part.

5. The anti-rollover wheel set for a light rail vehicle according to claim 4, wherein The bearing assembly includes an end cover and a bearing. The inner ring or outer ring of the bearing is fixedly connected with the rim part. The end cover is fixedly connected with the inner ring or outer ring of the bearing, and the end surface of the end cover abuts against the compression spring.

6. The anti-rollover wheel set for a light rail vehicle according to claim 5, wherein The abutting hole has a conical abutting surface.

7. The anti-rollover wheel set for a light rail vehicle according to claim 6, wherein The stroke of the first end to abut against the rim part is L1, and the stroke of the wheel body to abut against the rim part is L2. L1 < L2.

8. The anti-rollover wheel set for a light rail vehicle according to claim 7, wherein The wheel body is wrapped with a protective layer made of polyurethane material.

9. The anti-rollover wheel set for a light rail vehicle according to claim 8, wherein The protective layer of the wheel body has a plurality of anti-skid textures, and each anti-skid texture forms a circle around the axis of the wheel body.

10. A railcar comprising a light railcar anti-rollover wheelset according to any one of claims 1-9, characterized in that, The vehicle body and the driving device are included. The driving device is fixedly arranged in the vehicle body. The driving device is connected with the connecting shaft to drive the connecting shaft to rotate.

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