Railway vehicle bogies and railway vehicles

Abstract

To provide a railway vehicle bogie that requires no maintenance and exhibits minimal degradation in vibration damping effect even with long-term use. [Solution] The bogie for the railway vehicle has side beams equipped with vibration damping space structures at both ends, and the vibration damping space structure comprises a sealed space and a liquid sealed within the space, and the vibration of the railway vehicle bogie is suppressed by the liquid flowing within the space in response to the vibration of the railway vehicle bogie.

Description

Technical Field

[0001] The present invention relates to a bogie for a railway vehicle and a railway vehicle.

Background Art

[0002] As part of efforts to improve passenger comfort in railway vehicles, improving the riding comfort by reducing vehicle vibrations is an important technical issue in vehicle development.

[0003] An explanation will be given of the elastic vibration of the car body, which is one of the vibrations generated in railway vehicles. FIG. 11 is a diagram showing an example of the vibration mode of the car body when the bogie performs pitching vibration. The elastic vibration of the car body exaggeratedly shown in FIG. 11 is caused by the vibration of the bogie 16 that supports the car body 1. When the bogie 16 vibrates back and forth or pitches, a vibration force is generated in the longitudinal direction of the car body through the yaw damper 4 or the traction device (not shown) provided between the car body and the bogie. Therefore, the car body receives a bending moment 300, and the elastic vibration of the car body may be excited.

[0004] In order to suppress such elastic vibration of the car body, it is important to reduce the bogie vibration that excites the elastic vibration of the car body.

[0005] As a method for reducing bogie vibration, conventionally, for example, the technique described in Patent Document 1 is known.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] Patent Document 1 discloses a structure that reduces vibrations transmitted from a bogie frame to the vehicle body by sealing granular material inside the bogie frame. Specifically, a container filled with granular material is installed inside the side beam of the bogie. Vibrations from excitation sources such as track irregularities are transmitted from the wheels to the bogie frame via axle springs, etc., thereby generating vibration energy in the side beam of the bogie frame. This vibration energy is converted into kinetic energy of the granular material by collision with the granular material inside the container, which vibrates together with the side beam, thereby reducing vibration in the side beam of the bogie frame. As a result, vibrations from the wheels caused by track irregularities or wheel imbalances can be reduced in the side beam, and the propagation of vibrations to other parts can be suppressed.

[0008] According to the technology described in Patent Document 1, granular material impact is used to reduce vibrations transmitted from the bogie frame to the car body. As a result, the surface of the granular material wears down due to contact between the granular material itself or friction between the granular material and the inner wall of the side beam during long-term use. As wear progresses, the vibration damping effect deteriorates, requiring periodic maintenance such as replacement of the granular material. Furthermore, if the granular material becomes clogged and its movement is hindered, the vibration damping effect will decrease.

[0009] Therefore, the present invention aims to provide a railway vehicle bogie and railway vehicle that require no maintenance and whose vibration damping effect does not deteriorate even during long-term use. [Means for solving the problem]

[0010] To solve the above objective, one representative bogie for railway vehicles of the present invention is: It has side beams equipped with vibration-damping space structures at both ends, The aforementioned vibration-damping space structure is A sealed space, The space contains a liquid, This is achieved by suppressing the vibration of the railway vehicle bogie by allowing the liquid to flow within the space in response to the vibration of the railway vehicle bogie. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a railway vehicle bogie and railway vehicle that do not require maintenance and whose vibration damping effect does not deteriorate even after long-term use. Other issues, configurations, and effects not mentioned above will be clarified by the following description of the embodiments. [Brief explanation of the drawing]

[0012] [Figure 1] This is a side view of a railway vehicle according to Embodiment 1 of the present invention. [Figure 2] This is a plan view of a railway vehicle bogie according to Embodiment 1. [Figure 3] This is a side view of the side beam of a railway vehicle bogie according to Embodiment 1. [Figure 4] This figure shows an example of a water inlet for a space containing liquid inside the side beam of a railway vehicle bogie according to Embodiment 1. [Figure 5] This figure shows an example of a railway vehicle bogie according to a modified embodiment of Embodiment 1, in which a vibration damping container, manufactured separately from the side beam, is used to create a space containing liquid inside the side beam. [Figure 6] This diagram schematically illustrates the behavior of the bogie frame during longitudinal vibration. [Figure 7] This figure shows the effect of suppressing the vibration acceleration of the vehicle body by the railway vehicle bogie according to Embodiment 1, compared to a comparative example. [Figure 8] This is a side view of the side beam of a railway vehicle bogie according to Embodiment 2. [Figure 9] This figure shows an example of a railway vehicle bogie according to Embodiment 2, in which a vibration damping container, manufactured separately from the side beam in advance, constitutes a liquid-containing space inside the side beam. [Figure 10] This figure schematically shows the behavior of the bogie frame of the railway vehicle bogie according to Embodiment 2 during pitching vibration. [Figure 11] This diagram schematically illustrates the elastic vibration of a railway vehicle's body. [Modes for carrying out the invention]

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The directions used in the following description are defined as follows. In the vehicle body 1 shown in FIG. 1, the longitudinal direction (front-rear direction, traveling direction, rail direction) is the X direction, the width direction (sleeper direction, left-right direction) is the Y direction, and the height direction is the Z direction. The horizontal plane direction refers to the direction of the plane formed by the X direction and the Y direction. Note that the X direction, Y direction, and Z direction may simply be referred to as such.

[0014] [Embodiment 1] FIG. 1 is a side view of a railway vehicle according to Embodiment 1 of the present invention. In FIG. 1, the railway vehicle traveling on the track 2 is composed of a vehicle body 1 and a bogie 16 that supports the vehicle body 1. The vehicle body 1 is mounted on the bogie 16 via an air spring 8. The bogie 16 is composed of a bogie frame 11, an air spring 8, a yaw damper 4, a shaft damper 5, a wheel axle 13, a shaft spring device 14, a journal box 12 that serves as a bearing housing for the wheel axle 13, and a journal box support rubber 15, etc.

[0015] The wheel axles 13 are rotatably held with respect to the journal boxes 12 respectively installed in the sleeper direction (Y direction in FIG. 1). Between the journal boxes 12 and the bogie frame 11, they are elastically supported in the vertical direction (Z direction in FIG. 1) by the shaft spring device 14 and elastically supported in the horizontal plane direction by the journal box support rubber 15. An air spring 8 is disposed between the vehicle body 1 and the bogie frame 11, and the vehicle body 1 is elastically supported by the bogie frame 11 by this air spring 8.

[0016] FIG. 2 is a plan view of the bogie, and FIG. 3 is a side view of the side beam of the bogie. The bogie frame 11 forming the bogie 16 has a pair of side beams 71 spaced along the X direction, and a pair of cross beams 72 provided along the Y direction and penetrating the central portion of the side beams 71 in the X direction. Further, a pair of connecting beams 73 are provided on the cross beams 72 along the X direction.

[0017] The hollow cylindrical side beam 71, with both ends in the X direction closed, is provided with partition plates 21 that extend along the YZ planes, spaced apart from the closed ends, with the ends of the side beam 71 extending from the closed ends to the partition plates 21. The interior of both ends of the side beam 71 is a sealed space separated from the central part 71a in the X direction by the partition plates 21.

[0018] Liquid 22 is sealed within this sealed space, and the sealed space separated by the partition plate 21 and the liquid 22 constitute the vibration damping space structure 20. When the sealed space within the vibration damping space structure 20 is a rectangular parallelepiped, its dimension in the Y direction is W, its dimension in the X direction is L, and the height of the liquid 22 is H. In this case, the height H of the liquid 22 is determined so that the frequency of the trolley vibration to be reduced matches the natural frequency of the liquid's sloshing (liquid oscillation). The height H of the liquid is lower than the height of the sealed space, and everything except the liquid is air.

[0019] When the vibration-damping space structure 20 has a rectangular parallelepiped space as shown in Figures 2 and 3, the period T of liquid sloshing (=1 / F, where F is the frequency) can generally be calculated using the following equation (1). In equation (1), g is the acceleration due to gravity.

[0020]

number

[0021] Therefore, for example, if we denote the frequency of the trolley vibration to be reduced as F', the liquid height H can be calculated using the following equation (2), which is obtained by rearranging equation (1).

[0022]

number

[0023] As shown in Figure 4, after the bogie frame is completed, a vibration-damping space structure 20 containing liquid can be constructed inside the bogie frame by injecting liquid 22 into the sealed space at both ends of the side beam, which is separated by a partition plate 21, through a liquid supply port 25 provided on the upper surface (or side) of the side beam. Alternatively, after injecting liquid 22 into the side beam through the liquid supply port 25, which is an opening that penetrates into the side beam, the liquid supply port 25 may be sealed with a lid or sealant. Furthermore, a drain port may be provided on the lower surface or side of the side beam to discharge the liquid 22 from the sealed space.

[0024] (modified version) Figure 4 shows an example in which the vibration damping space structure 20 is configured as part of the side beam 71. However, as shown in Figure 5, the vibration damping space structure 20 may also be manufactured as a separate part from the side beam 71. Specifically, a rectangular parallelepiped-shaped vibration damping container (also called a vibration damping space structure) 30, which is pre-filled with liquid 22, may be manufactured before assembling the side beam. The vibration damping container 30 may then be attached to the side beam end wall by adhesive or bolting during the assembly of the side beam. In this case, compared to configuring the vibration damping space structure as part of the side beam as shown in Figure 4, manufacturing the vibration damping container 30 separately offers the advantage of increased design flexibility in terms of shape and capacity. Furthermore, there is no need to provide a liquid inlet 25 on the top or side of the side beam, and the effort of injecting liquid 22 after the side beam is assembled is eliminated.

[0025] In addition to water and antifreeze, other highly viscous fluids such as heavy mud water, which have properties such as high specific gravity and high viscosity, can be used as the liquid 22.

[0026] Next, using Figure 6, we will explain the mechanism by which the bogie for a railway vehicle with the above configuration reduces vibrations transmitted to the vehicle body. Figure 6 is a schematic diagram showing the behavior (vibration mode) of the bogie of Embodiment 1 during longitudinal vibration.

[0027] At frequencies where longitudinal vibration of the bogie is dominant, as shown in Figure 6, if longitudinal vibration 101 occurs in the bogie, the liquid 22 in the vibration-damping space structure 20 will undulate and repetitively flow within the sealed space in response to the longitudinal vibration 101 of the bogie. Here, if the height H of the liquid 22 in the vibration-damping space structure 20 is a predetermined amount according to equation (2), the reaction force 102 on the bogie caused by the sloshing of the liquid occurring within the sealed space (the force generated when the flowing liquid hits the partition plate 21 and the closed end) acts in the opposite direction to the longitudinal vibration 101 of the bogie.

[0028] The reaction force 102 due to the sloshing of this liquid acts in a direction that counteracts the peak longitudinal vibration 101 of the bogie, thus effectively reducing the peak of the longitudinal vibration of the bogie. Therefore, vibrations transmitted from the bogie to the car body can be reduced, for example, the elastic vibration of the car body caused by bogie vibrations can be reduced.

[0029] Figure 7 shows the power spectral density (PSD) of the vertical acceleration of the vehicle body. The solid line 60 is an example (comparative example) of the vertical acceleration PSD of a railway vehicle that does not have a vibration damping space structure at the end of the side beam. On the other hand, the dotted line 61 is an example of the vertical acceleration PSD of the vehicle body according to this embodiment. Comparing the solid line 60 and the dotted line 61, it is clear that in the structure of this embodiment, the sloshing reaction force of the liquid can greatly reduce the longitudinal vibration of the bogie at frequency F'. Therefore, if it is clear that the peak of the longitudinal vibration of the bogie occurs at frequency F', the height of the peak of the vertical acceleration PSD in the elastic vibration of the vehicle body can be reduced by adjusting the height H of the liquid 22 accordingly, thereby reducing the vibration transmitted to the vehicle body.

[0030] As described above, the above configuration suppresses longitudinal bogie vibrations by utilizing the reaction force of liquid sloshing generated in response to longitudinal bogie vibrations, thereby reducing vibrations transmitted from the bogie to the car body and improving the ride comfort of the vehicle. Furthermore, since it is a vibration-damping space structure that uses only liquid, it has the advantage of requiring no maintenance.

[0031] [Embodiment 2] A railway vehicle bogie according to Embodiment 2 of the present invention will be described with reference to Figures 8 to 10. Note that components or processes similar to those described in Embodiment 1 are denoted by the same reference numerals, and their detailed descriptions are omitted. Only the differences from Embodiment 1 will be described below.

[0032] Figure 8 is a side view of the side beam of a railway vehicle bogie according to Embodiment 2. In this embodiment, the bottom surface of the vibration damping space structure 20 is made of an inclined bottom plate 23. Alternatively, if the vibration damping space structure 20 is manufactured as a separate part from the side beam 71, as shown in Figure 9, the vibration damping container 30' may be manufactured so that its bottom surface is inclined, and then the vibration damping container 30' may be attached to the inner wall of the side beam by adhesive or bolt fastening during the assembly of the side beam to form the vibration damping space structure. The bottom surface of the vibration damping space structure 20 is a flat surface in contact with the liquid 22.

[0033] In contrast to the embodiments described above, the bogie of this embodiment differs in that the bottom surfaces of the vibration damping space structures 20 at both ends of the side beam 71 (or the bottom surfaces of the vibration damping containers 30') are inclined with respect to the horizontal plane (XY plane) of the bogie frame so that they gradually rise toward the center of the bogie frame when viewed from the side of the bogie.

[0034] Next, using Figure 10, we will explain the mechanism by which the bogie for a railway vehicle with the above configuration reduces vibrations transmitted to the vehicle body. Figure 10 is a schematic diagram showing the behavior (vibration mode) of the bogie of the second embodiment during pitching (rotational direction around the Y-axis) vibration.

[0035] Assuming that a counterclockwise pitching vibration 106 occurs in the bogie at the frequency where pitching vibration of the bogie is dominant, as shown in Figure 10, the reaction force 107 on the bogie caused by the sloshing of the liquid occurs parallel to the bottom surface of the inclined bottom plate 23 of the vibration damping space structure 20, which is inclined with respect to the horizontal plane. Therefore, the length J of the moment arm in the pitching direction between the sloshing reaction force 107 and the bogie's center of gravity 200 is greater than the length of the moment arm when the bottom surface is horizontal. Consequently, the clockwise countermoon 110 generated by the sloshing reaction force 107 is greater than the countermoon when the bottom surface is horizontal, thus improving the vibration damping effect of the bogie's pitching vibration. This suppresses pitching vibration, reduces vibrations transmitted from the bogie to the car body, and improves the ride comfort of the vehicle.

[0036] In the first or second embodiment, it is preferable that the liquid 22 is injected into the vibration-damping space structure in an amount such that the frequency at which the longitudinal vibration or pitching vibration of the bogie peaks matches the natural frequency of the sloshing of the liquid 22.

[0037] According to the embodiment described above, the sloshing characteristics of the liquid 22 hardly deteriorate even after long-term use, maintenance such as replacement of the liquid 22 is unnecessary, and a railway vehicle bogie is provided that does not easily experience a decrease in vibration damping effect even after long-term use.

[0038] This specification includes disclosures of the following inventions. (First aspect) In railway vehicle bogies, It has side beams equipped with vibration-damping space structures at both ends, The aforementioned vibration-damping space structure is A sealed space, The space contains a liquid, The fluid flows within the space in response to the vibration of the railway vehicle bogie, thereby suppressing the vibration of the railway vehicle bogie. A bogie for railway vehicles characterized by the following features.

[0039] (Second aspect) A railway vehicle bogie as described in the first embodiment, The aforementioned space is formed between the closed end and the partition plate, which is spaced apart from the closed end in the longitudinal direction of the hollow cylindrical side beam. The side beam has a liquid inlet for injecting liquid into the space. A bogie for railway vehicles characterized by the following features.

[0040] (Third aspect) A railway vehicle bogie according to the second embodiment, Having a lid or sealing material to seal the liquid inlet, A bogie for railway vehicles characterized by the following features.

[0041] (Fourth aspect) A railway vehicle bogie as described in the first embodiment, The aforementioned vibration-damping space structure is It is assembled to the side beam and consists of a vibration-damping container that encloses the space and the liquid, A bogie for railway vehicles characterized by the following features.

[0042] (Fifth aspect) A railway vehicle bogie according to any of the first to fourth embodiments, The liquid is injected into the space in an amount such that the frequency at which the longitudinal vibration of the railway vehicle bogie peaks matches the natural frequency of the liquid's sloshing. A bogie for railway vehicles characterized by the following features.

[0043] (Sixth aspect) A railway vehicle bogie according to the first to fifth embodiments, The bottom surface of the space in contact with the liquid is inclined with respect to the horizontal plane. A bogie for railway vehicles characterized by the following features.

[0044] (Seventh aspect) A railway vehicle bogie according to the sixth embodiment, The bottom surface is inclined to gradually rise towards the center of the railway vehicle bogie when viewed from the side of the railway vehicle bogie. A bogie for railway vehicles characterized by the following features.

[0045] (Eighth aspect) A bogie for a railway vehicle according to the sixth or seventh embodiment, The liquid is injected into the space in an amount such that the frequency at which the pitching vibration of the railway vehicle bogie peaks matches the natural frequency of the liquid's sloshing. A bogie for railway vehicles characterized by the following features.

[0046] (Ninth aspect) Having a railway vehicle bogie of any of the first to eighth embodiments, A railway vehicle characterized by the following features. [Explanation of Symbols]

[0047] 1 car body, 2 tracks, 11 bogie frames, 13 wheelsets, 16 bogies, 20 Vibration-damping space structure, 21 Partition plate, 22 Liquid, 23 Slanted bottom plate, 25 Liquid inlet, 30 Vibration damping container, 71 Side beam, 72 Crossbeam, 73 Connecting beam

Claims

1. In railway vehicle bogies, It has side beams equipped with vibration-damping space structures at both ends, The aforementioned vibration-damping space structure is A sealed space, The space contains a liquid, The fluid flows within the space in response to the vibration of the railway vehicle bogie, thereby suppressing the vibration of the railway vehicle bogie. A bogie for railway vehicles characterized by the following features.

2. A railway vehicle bogie according to claim 1, The aforementioned space is formed between the closed end and the partition plate, which is spaced apart from the closed end in the longitudinal direction of the hollow cylindrical side beam. The side beam has a liquid inlet for injecting liquid into the space. A bogie for railway vehicles characterized by the following features.

3. A railway vehicle bogie according to claim 2, Having a lid or sealing material to seal the liquid inlet, A bogie for railway vehicles characterized by the following features.

4. A railway vehicle bogie according to claim 1, The aforementioned vibration-damping space structure is It is assembled to the side beam and consists of a vibration-damping container that encloses the space and the liquid, A bogie for railway vehicles characterized by the following features.

5. A railway vehicle bogie according to claim 1, The liquid is injected into the space in an amount such that the frequency at which the longitudinal vibration of the railway vehicle bogie peaks matches the natural frequency of the liquid's sloshing. A bogie for railway vehicles characterized by the following features.

6. A railway vehicle bogie according to claim 1, The bottom surface of the space in contact with the liquid is inclined with respect to the horizontal plane. A bogie for railway vehicles characterized by the following features.

7. A railway vehicle bogie according to claim 6, The bottom surface is inclined to gradually rise towards the center of the railway vehicle bogie when viewed from the side of the railway vehicle bogie. A bogie for railway vehicles characterized by the following features.

8. A railway vehicle bogie according to claim 6, The liquid is injected into the space in an amount such that the frequency at which the pitching vibration of the railway vehicle bogie peaks matches the natural frequency of the liquid's sloshing. A bogie for railway vehicles characterized by the following features.

9. A railway vehicle bogie having the one described in any one of claims 1 to 8, A railway vehicle characterized by the following features.

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