Axle box support device and elastic bushing axle body for railway vehicle

Abstract

The elastic bushing has a recessed portion in which a portion of an outer peripheral surface thereof on the vehicle length direction inner side is recessed toward the vehicle length direction outer side. The tubular portion of the axle beam has a convex stopper portion protruding from a portion of an inner peripheral surface thereof on the vehicle length direction inner side toward the vehicle length direction outer side and inserted into the recessed portion in a state in which a gap is provided between the bottom surface of the recessed portion and the convex stopper portion. The radial direction thickness in the recessed portion of the elastic bushing is half or less of the radial direction thickness in a portion of the elastic bushing that is adjacent to the recessed portion.

Description

Technical Field

[0001] The present invention relates to an axle box support device and an elastic bushing axle body for connecting the axle box to the bogie frame in a bogie of a railway vehicle having a tread brake that presses against the tread of the wheel from the inside in the longitudinal direction of the vehicle. Background Technology

[0002] Axle box support devices for railway vehicle bogies are known to include axle beam type axle box support devices. In axle beam type axle box support devices, a rubber bushing with a mandrel inserted is inserted into the cylindrical portion of the axle beam protruding from the axle box, and the two ends of the mandrel extending from the rubber bushing are connected to the bogie frame. From the viewpoint of running performance, it is ideal when the spring constant of the rubber bushing is relatively small. However, when the tread brake is engaged, the axle beam is strongly pushed outward in the vehicle's length direction, causing a large displacement outward relative to the mandrel in the vehicle's length direction. Therefore, if the spring constant of the rubber bushing is small, the rubber will deform significantly. Therefore, from the viewpoint of ensuring the durability of the rubber, it has been proposed to incorporate a displacement suppression mechanism into the rubber bushing (see Patent Document 1).

[0003] Existing technical documents:

[0004] Patent documents:

[0005] Patent document 1: Japanese Patent Application Publication No. 2017-43142. Summary of the Invention

[0006] The problem that the invention aims to solve:

[0007] However, in the structure of Patent Document 1, the displacement suppression mechanism is located inside the rubber bushing, which complicates the construction of the rubber bushing and increases the cost of the component.

[0008] Therefore, the object of the present invention is to provide a beam-type axle box support device that prevents excessive deformation of the elastic bushing installed between the axle beam and the spindle in the vehicle length direction, and suppresses the increase in cost.

[0009] Problem-solving methods

[0010] One aspect of the present invention is an axle box support device for railway vehicles, which connects the axle box to the bogie frame in a bogie equipped with a tread brake that presses against the wheel tread from the inside in the vehicle's length direction. The device comprises: an axle beam connecting the axle box to the bogie frame, the axle beam having a beam portion extending from the axle box along the vehicle's length direction and a cylindrical portion provided at the tip of the beam portion and open on both sides in the vehicle width direction; and a mandrel inserted through the internal space of the cylindrical portion and having a portion protruding on both sides in the vehicle width direction and supported on the bogie frame. The protrusion; and a cylindrical elastic bushing disposed between the cylindrical portion and the spindle; the elastic bushing having a recessed portion on its outer circumferential surface in the vehicle length direction inward toward the outer side in the vehicle length direction; the cylindrical portion having a convex stop portion protruding from its inner circumferential surface in the vehicle length direction inward toward the outer side in the vehicle length direction and inserted into the recessed portion with a gap between it and the bottom surface of the recessed portion; the radial thickness of the recessed portion of the elastic bushing is less than half of the radial thickness of the portion of the elastic bushing adjacent to the recessed portion.

[0011] According to the above structure, when the wheel is pushed outward in the vehicle's length direction due to the operation of the tread brake, causing the axle beam to displace significantly outward relative to the spindle, the tip face of the stop portion of the cylindrical part of the axle beam presses against the bottom surface of the recessed portion of the elastic bushing, receiving a resistance force from the spindle bearing towards the inward direction in the vehicle's length direction. This limits excessive outward displacement of the axle beam relative to the spindle in the vehicle's length direction when the tread brake is engaged, preventing excessive deformation of the elastic bushing. Furthermore, since the stop portion is located in the cylindrical part of the axle beam and has higher strength than the elastic bushing, even if they come into contact, the low-cost elastic bushing can be damaged. Also, since the structure of the elastic bushing does not need to be complex, cost increases are suppressed. Therefore, excessive deformation of the elastic bushing, which is installed between the axle beam and the spindle, in the vehicle's length direction can be prevented, and cost increases can be suppressed.

[0012] Another embodiment of the present invention is an axle box support device for railway vehicles, which connects the axle box to the bogie frame in a bogie equipped with a tread brake that presses against the wheel tread from the inside in the vehicle length direction. The axle box support device comprises: an axle beam connecting the axle box to the bogie frame, the axle beam having a beam portion extending from the axle box along the vehicle length direction and a cylindrical portion provided at the tip of the beam portion and open on both sides in the vehicle width direction; a mandrel inserted through the internal space of the cylindrical portion and provided with a pair of protrusions protruding on both sides in the vehicle width direction and supporting the bogie frame; and a cylindrical elastic bushing interposed between the cylindrical portion and the mandrel; the axle beam having a stop portion facing each other in the vehicle length direction from the inside in the vehicle length direction relative to the mandrel or a part of the bogie frame with a gap; the vehicle length direction dimension of the gap is smaller than the thickness of the elastic bushing.

[0013] According to the above structure, when the wheel is pushed outward in the vehicle's length direction due to the operation of the tread brake, causing the axle beam to displace significantly outward relative to the spindle, the stop portion of the axle beam interferes with the spindle or bogie frame. This limits excessive outward displacement of the axle beam relative to the spindle in the vehicle's length direction when the tread brake is engaged, preventing excessive deformation of the elastic bushing. Furthermore, since the stop portion is located on the axle beam, it can be visually inspected from the outside without disassembling the bogie, making inspection easy. Also, since there is no need for a special structure for the elastic bushing, cost increases are suppressed. Therefore, excessive deformation of the elastic bushing between the axle beam and spindle in the vehicle's length direction can be prevented, cost increases can be suppressed, and inspection can be easily performed.

[0014] Invention effects:

[0015] According to the present invention, excessive deformation of the elastic bushing between the axle beam and the spindle in the vehicle length direction can be prevented, and the increase in cost can be suppressed and inspection can be easily carried out. Attached Figure Description

[0016] Figure 1 This is a side view of the bogie of a railway vehicle in its first embodiment, viewed from the width direction.

[0017] Figure 2 yes Figure 1 Side view of the axle box support device of the bogie shown;

[0018] Figure 3 yes Figure 2 Sectional view along line III-III;

[0019] Figure 4 yes Figure 3 Sectional view along line IV-IV;

[0020] Figure 5 yes Figure 4 A perspective view of the second half-cylinder as seen from the inner circumferential side;

[0021] Figure 6 It is equivalent to the variant example Figure 4 The image;

[0022] Figure 7 This is a horizontal sectional view of the cylindrical portion of the shaft beam and its vicinity in the second embodiment.

[0023] Figure 8 yes Figure 7 A three-dimensional view of the cylindrical section and its vicinity. Detailed Implementation

[0024] The following description refers to the embodiments. In addition, in the following description, the vehicle's driving direction is defined as the vehicle's length direction (front-to-back direction), and the lateral direction orthogonal to it is defined as the vehicle's width direction (left-to-right direction).

[0025] (First Implementation Form)

[0026] Figure 1 This is a side view of the bogie 1 of a railway vehicle in its first embodiment, viewed from the width direction. (Example) Figure 1 As shown, the bogie 1 includes a bogie frame 4 that supports the vehicle body 2 via a secondary suspension 3 (e.g., air springs). A pair of axles 5 are arranged on both sides of the bogie frame 4 in the vehicle length direction. Each axle 5 has an axle 5a extending in the vehicle width direction and wheels 5b located on both sides of the axle 5a.

[0027] Both ends of axle 5a in the vehicle width direction are housed in axle boxes 7 via bearings 6. Axle boxes 7 are connected to bogie frames 4 via axle beam-type axle box support device 8. A primary suspension 9 (e.g., a coil spring) is provided between the bogie frame 4 and the axle boxes 7. A tread brake 10 is positioned opposite the tread of wheel 5b, pressing the tread of wheel 5b from the inside to the outside in the vehicle length direction.

[0028] Figure 2 yes Figure 1 The side view of the axle box support device 8 of the bogie 1 shown. Figure 2 As shown, the axle box support device 8 includes an axle beam 11 that connects the axle box 7 to the bogie frame 4. The axle beam 11 has a beam portion 12 that extends integrally from the axle box 7 toward the center of the bogie in the vehicle length direction, and a cylindrical portion 13 provided at the tip of the beam portion 12. The cylindrical portion 13 has an inner circumferential surface in the shape of a cylinder with its axis pointing toward the vehicle width direction, and opens to both sides in the vehicle width direction.

[0029] The cylindrical portion 13 is divided into two parts along the length of the vehicle. Specifically, the cylindrical portion 13 is divided into a first half-cylinder portion 14 integrally provided at the tip of the beam portion 12, and a second half-cylinder portion 15 independent of the first half-cylinder portion 14 and overlapping the first half-cylinder portion 14 from the inside along the length of the vehicle. The second half-cylinder portion 15 is fixed to the first half-cylinder portion 14 by means of fastening members B1 (e.g., bolts and nuts).

[0030] Figure 3 yes Figure 2 Sectional view along line III-III. (See also...) Figure 2 and 3 As shown, a mandrel 16 is inserted into the internal space of the cylindrical portion 13. The mandrel 16 has a cylindrical portion 16a, a pair of conical flange portions 16b provided on both sides of the cylindrical portion 16a in the vehicle width direction, and protrusions 16c protruding outward from both sides of the pair of flange portions 16b in the vehicle width direction. The protrusions 16c protrude from the cylindrical portion 13 to both sides in the vehicle width direction.

[0031] An elastic bushing 17 is installed between the cylindrical portion 13 and the mandrel 16. The elastic bushing 17 is, for example, a rubber bushing. The elastic bushing 17 has a cylindrical portion 17a and a pair of conical flange portions 17b provided on both sides of the cylindrical portion 17a in the machine width direction, and is externally fitted and vulcanized to the mandrel 16. That is, the mandrel 16 and the elastic bushing 17, which are integral with each other, constitute the elastic bushing shaft body 22. The cylindrical portion 17a of the elastic bushing 17 is bonded to the cylindrical portion 16a of the mandrel 16. The flange portions 17b of the elastic bushing 17 are bonded to the flange portions 16b of the mandrel 16. The first half-cylinder portion 14 and the second half-cylinder portion 15 are fixed to each other by means of the fastening member B1, and the mandrel 16 is clamped by the elastic bushing 17. The cylindrical portion 13 is allowed relative displacement with respect to the spindle 16 in the forward and backward, left and right, up and down and in the direction of rotation about the width of the machine, thanks to the elasticity of the elastic bushing 17.

[0032] A pair of support seats 18 are provided on the bogie frame 4, protruding downwards. Each of the support seats 18 has a groove 18a that is open downwards and on both sides in the vehicle width direction. A protrusion 16c of a spindle 16 is inserted into the groove 18a from below. In this state, with the cover member 19 supporting the lower surface of the protrusion 16c of the spindle 16, the cover member 19 is fixed to the support seat 18 from below by means of a fastening member B2 (e.g., a bolt).

[0033] Figure 4 yes Figure 3 Sectional view along line IV-IV. Figure 5 yes Figure 4 A perspective view of the second semi-cylindrical portion 15 as seen from its inner circumferential surface. (See diagram below.) Figure 4 and Figure 5As shown, the elastic bushing 17 has, for example, a cylindrical rubber tube body 20 and a cylindrical outer shell 21 covering the outer peripheral surface of the rubber tube body 20. The elastic bushing 17 has a recess 17c on the portion of its outer peripheral surface that is recessed toward the outer peripheral surface in the vehicle length direction. The radial thickness T1 in the recess 17c of the elastic bushing 17 is less than half of the radial thickness T2 in the other portions of the elastic bushing 17 adjacent to the recess 17c, preferably less than 40%, more preferably less than 30%.

[0034] The second semi-cylindrical portion 15 has a convex stop portion 15a that protrudes from the inner side of its inner circumferential surface in the vehicle length direction toward the outer side in the vehicle length direction. The stop portion 15a has a tip surface 15b that faces outward in the vehicle length direction. The shape of the tip surface 15b is not particularly limited, but in this embodiment, the tip surface 15b of the stop portion 15a has a shape that is longer in the direction along the length direction (vehicle width direction) of the spindle 16. The tip surface 15b can be, for example, an oblong shape, an ellipse, a quadrilateral shape, etc. For example, the tip surface 15b of the stop portion 15a can also be made into a curved shape corresponding to the outer circumferential surface of the spindle 16 to increase the pressure area of ​​the tip surface 15b facing the spindle 16. Furthermore, the stop portion 15a can also be a separate structure that is fixed to the semi-cylindrical portion 15 by fitting or fastening. The stop portion 15a is positioned at the same height as the axis of the spindle 16, and is horizontally facing the spindle 16 from the inside of the vehicle length direction (the center side of the bogie) relative to the vertical center of the spindle 16.

[0035] With the second half-cylinder 15 fixed to the first half-cylinder 14, the stop portion 15a is inserted into the recess 17c with a gap C between the bottom surface 17d of the recess 17c of the elastic bushing 17 and the tip end face 15b. The maximum length of the tip end face 15b in the surface direction of the thickness of the elastic bushing 17 is 25% or more, preferably 30% or more, and more preferably 40% or more of the outer diameter of the cylindrical portion 16a of the mandrel 16. In this embodiment, the tip end face 15b is oblong, so the width W in the surface direction of the tip end face 15b (i.e., the width in the machining width direction) is 25% or more, preferably 30% or more, and more preferably 40% or more of the outer diameter of the cylindrical portion 16a. In this embodiment, if the shape of the tip end face 15b of the stop portion 15a is such that it extends in the length direction (machine width direction) of the mandrel 16, the pressure-bearing area of ​​the stop portion 15a bearing pressure from the mandrel 16 can be appropriately increased.

[0036] According to the structure described above, when the wheel 5b is pushed outward in the vehicle's length direction due to the operation of the tread brake 10, causing the axle beam 11 to displace significantly outward relative to the spindle 16, the tip face 15b of the stop portion 15a of the cylindrical portion 13 of the axle beam 11 presses against the bottom surface 17d of the recess 17c of the elastic bushing 17, thus bearing resistance from the spindle 16 towards the inward direction in the vehicle's length direction. This limits excessive outward displacement of the axle beam 11 relative to the spindle 16 in the vehicle's length direction when the tread brake 10 is operating, preventing excessive deformation of the rubber sleeve body 20 of the elastic bushing 17. Therefore, the spring constant of the elastic bushing 17 can be reduced, and driving performance can be improved. Furthermore, since there is a gap C between the stop portion 15a and the bottom surface 17d of the recess 17c, the stop portion 15a will not obstruct the elastic deformation of the elastic bushing 17 in the vehicle's length direction when the tread brake 10 is not operating.

[0037] Furthermore, the stop portion 15a, having a tip face 15b, is provided in the cylindrical portion 13 of the axle beam 11. Its strength is higher than that of the elastic bushing 17, so even if they come into contact, the lower-cost elastic bushing 17 can be damaged. Also, since the construction of the elastic bushing 17 does not need to be complicated, cost increases are suppressed. Therefore, excessive deformation of the elastic bushing 17, which is installed between the axle beam 11 and the spindle 16, in the vehicle length direction can be prevented, and cost increases can be suppressed.

[0038] Furthermore, the maximum length of the end face 15b in the planar direction is more than 25% of the outer diameter of the cylindrical portion 16a of the spindle 16. Therefore, when the tread brake 10 is working and the end face 15b of the stop portion 15a bears resistance from the spindle 16, the force per unit area borne by the end face 15b is prevented from being too large, thereby improving the durability of the stop portion 15a and the elastic bushing 17. In addition, the stop portion 15a and the recess 17c can also function as a locating pin to prevent the elastic bushing 17 from rotating relative to the cylindrical portion 13, eliminating the need for a separate locating pin.

[0039] Figure 6 It is equivalent to the variant example Figure 4 The diagram. For example... Figure 6 As shown, as a variation, the cylindrical portion 113 of the shaft beam 111 can also be divided into upper and lower sections. The cylindrical portion 113 is divided into a first semi-cylindrical portion 114 integrally formed at the tip of the beam portion 112, and a second semi-cylindrical portion 115 independent of the first semi-cylindrical portion 114 and overlapping the first semi-cylindrical portion 114 from below. The second semi-cylindrical portion 115 is fixed to the first semi-cylindrical portion 114 by means of a fastening member (not shown). Alternatively, the first semi-cylindrical portion 114 and the second semi-cylindrical portion 115 can also be arranged in a configuration where they are reversed vertically.

[0040] The first half-cylinder portion 114 includes a stop portion 114a, which protrudes from the inner side of its inner circumferential surface in the vehicle length direction outward in the vehicle length direction, and has a tip surface 114b facing outward in the vehicle length direction. Since the stop portion 114a is positioned at the same height as the axis O of the spindle 16, the portion of the first half-cylinder portion 114 in which the stop portion 114a is located protrudes downward beyond the axis O of the spindle 16. Furthermore, the other structures are the same as in the first embodiment described above, and therefore, descriptions are omitted. Alternatively, the first half-cylinder portion and the second half-cylinder portion can be vertically divided along a horizontal line passing through the axis of the spindle, and the stop portion can be divided into a first half-stop portion provided in the first half-cylinder portion and a second half-stop portion provided in the second half-cylinder portion. In this case, the stop portion can be shaped to allow the first half-cylinder portion and the second half-cylinder portion to be mounted and dismounted in the vertical direction without interfering with the elastic bushing.

[0041] (Second Implementation Form)

[0042] Figure 7 This is a horizontal sectional view of the cylindrical portion 213 and its vicinity of the second embodiment of the shaft beam 211. Figure 8 yes Figure 7 The diagram shows a perspective view of the cylindrical portion 213 and its vicinity. Furthermore, structures common to the first embodiment are labeled with the same symbols and their descriptions are omitted. (See diagram for reference.) Figure 7 and Figure 8 As shown, in the second embodiment, the axle beam 211 has a beam portion 212 and a cylindrical portion 213, the cylindrical portion 213 having a tread brake 10 (see reference). Figure 1 During operation, a stop portion 213a is provided to prevent excessive displacement of the axle beam 211 relative to the spindle 16. The stop portion 213a faces the flange portion 16b, which is a portion of the spindle 16 that extends outward in the vehicle width direction beyond the elastic bushing 17, with a gap C separating them along the vehicle length direction. Specifically, the stop portion 213a protrudes from the tip of the cylindrical portion 213 on the inner side (center side of the bogie) in the vehicle length direction to both sides in the vehicle width direction. In this embodiment, the stop portion 213a is formed to be thicker than the other portions of the cylindrical portion 213 adjacent to it. The gap C between the stop portion 213a and the flange portion 16b of the spindle 16 has a dimension in the vehicle length direction smaller than the thickness of the elastic bushing 17.

[0043] Based on the above structure, due to the tread brake 10 (refer to...) Figure 1 The work of ) will cause the wheel 5b (refer to) Figure 1When the axle beam 211 is pushed outward in the vehicle's length direction, causing a significant outward displacement relative to the spindle 16, the stop portion 213a of the cylindrical portion 213 of the axle beam 211 interferes with the flange portion 16b of the spindle 16. This limits excessive outward displacement of the axle beam 211 relative to the spindle 16 in the vehicle's length direction when the tread brake 10 is engaged, preventing excessive deformation of the elastic bushing 17. Therefore, the spring constant of the elastic bushing 17 can be reduced, and driving performance can be improved.

[0044] Furthermore, the stop portion 213a is provided on the axle beam 211, allowing for visual inspection from the outside even without disassembling the bogie, thus facilitating inspection. Also, since there is no need to design a special structure for the elastic bushing 17, cost increases can be suppressed. Therefore, excessive deformation of the elastic bushing 17, which is installed between the axle beam 211 and the spindle 16, in the vehicle length direction can be prevented, cost increases can be suppressed, and inspection can be easily performed.

[0045] Furthermore, the cylindrical portion 213 can be a structure divided into left and right sections or top and bottom sections, or it can be an undivided structure. Also, the stop portion 213a does not necessarily have to be provided in the cylindrical portion 213. For example, it can be configured such that a stop portion is provided on the beam portion 212 of the axle beam 211, and when the axle beam 211 is to move excessively outward in the vehicle length direction relative to the spindle 16 (and the bogie frame 4), this stop portion interferes with the bogie frame 4 (e.g., support seat 18). Furthermore, the bogie 1 can also be configured such that, instead of using a coil spring in the primary suspension 9, a leaf spring is used, omitting the side beam from the bogie frame; a pair of front and rear axle boxes 7 respectively support the ends of the leaf spring on both sides in the length direction from below, and the central portion of the leaf spring in the length direction supports the crossbeam of the bogie frame from below.

[0046] Symbol explanation:

[0047] 1. Bogie;

[0048] 4. Bogie frame;

[0049] 5b Wheel;

[0050] 7. Axle box;

[0051] 8. Axle box support device;

[0052] 10. Tread brake;

[0053] Beams on shafts 11, 111, and 211;

[0054] Beam sections 12, 112, and 212;

[0055] 13, 113, 213 cylindrical part;

[0056] Stops in models 15a, 114a, and 213a;

[0057] 15b, 114b tip face;

[0058] 16 spindles;

[0059] 16a Cylindrical portion;

[0060] 16b Flange portion;

[0061] 16c Protrusion;

[0062] 17. Elastic bushing;

[0063] 17c concavity;

[0064] 17d base;

[0065] 22. Elastic bushing shaft;

[0066] C gap.

Claims

1. A railway vehicle axle box support device, characterized in that, It is an axle box support device for railway vehicles that connects the axle box to the bogie frame in a bogie equipped with a tread brake that presses against the wheel tread from the inside in the length direction of the vehicle, and includes: The axle beam connecting the axle box to the bogie frame has a beam portion extending from the axle box along the vehicle length direction and a cylindrical portion provided at the end of the beam portion and open on both sides in the vehicle width direction. A mandrel, which is inserted through the internal space of the cylindrical portion and has a pair of protrusions extending to both sides in the vehicle width direction and supporting the bogie frame; and A cylindrical elastic bushing is installed between the cylindrical portion and the mandrel; The axle beam has a stop portion facing each other in the vehicle length direction from the inside of the vehicle length direction, in a state of being separated from the spindle or a part of the bogie frame by a gap; The length dimension of the gap in the vehicle direction is smaller than the thickness of the elastic bushing; The stop portion protrudes partially in the vehicle width direction from the inner side of the cylindrical portion in the vehicle length direction, and faces each other in the vehicle length direction, separated by the gap from the portion of the spindle that protrudes outward in the vehicle width direction than the elastic bushing.

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