JPH031442B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to the reduction of running noise of a rectangular monorail vehicle, and particularly to soundproofing of a monorail track suitable for reducing tire impact noise when running on a track girder. It's about walls.

[Background of the invention]

Traditionally, running noise countermeasures for monorail vehicles include reducing the noise level of individual equipment such as the main electric motor of the bogie, reducer, current collector, and tires, which are the sources of sound, as well as implementing noise-blocking or sound-absorbing treatments by enclosing the vehicle body. ing.

In addition, for rectangular monorail vehicles, sound damping plates are installed all over the lower surface of the track girder to block the sound radiated to the lower surface of the girder, or a special cross section in which the rectangular cross section of the track girder is widened only on the lower surface to form a convex shape. An example of this is to prevent noise from being radiated from the bottom surface.

Among the noise source measures mentioned above, noise from tires (especially drive tires) needs adhesive strength, is made of rubber tires, has a large number of tires (four on one bogie), and eliminates the level difference at track girder joints. Due to the difficulty of generating noise, the sound is particularly high-pitched compared to other sound sources, which is a factor that hinders noise reduction. The specific values of these noise levels are that the impact sound of tires passing over steps is 5 to 7 dB higher than the general driving level on concrete surfaces, which is a problem.

[Purpose of the invention]

The purpose of the present invention is to reduce the noise transmitted to the ground among the noise generated from the track girder joints on elevated tracks on which straddle-type monorail vehicles run, and also to simplify the structure and prevent sunlight obstruction. The objective is to provide soundproof walls for monorail tracks that can be used.

[Summary of the invention]

The present invention provides a soundproof wall for a monorail track in which a joint portion of a track girder on which a straddle-type monorail vehicle runs is supported by a girder receiver, from the upper part of the girder receiver to the longitudinal center of each track girder and in the width direction of the track girder. A soundproof wall extending to the girder is installed on the girder support, and the dimension from the driving girder joint side to the longitudinal end of the track girder of each soundproof wall is at least longer than the distance between the axes of both bogies, and each soundproof wall is It is characterized in that the walls are made of a sound-insulating material with a sound-absorbing material provided on the upper surface.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. Fig. 1 shows the relationship between the track girder near the support and vehicle tires, and Figures 2 and 3 show the attachment relationship between the support girder and the soundproof wall. 1 and 2 are front and rear track girders, 3 is a car body, and 4 is a bogie. In the bogie 4 , 7 is a driving tire, 18 is a guide tire, and 14 is a stabilizing tire. 17 is the joint between orbital girders 1 and 2;
8 is a finger plate on the top surface, 9 and 9' are finger plates on the side surfaces, and 5 is a column with a girder receiver 13 on the upper part, which is connected to the track beams 1 and 2 by a large gel 12. 11 is a cable rack for wiring installed under the girder (larger 12 is installed in the part of the column 5)
The position is shown in Figure 3 for . ). 10 is a girder receiver 13 at the bottom of the joint part of the track girders 1 and 2.
This is a soundproof wall that extends outward from the upper surface portion, that is, extends toward the center in the longitudinal direction of the track girders 1 and 2, and extends in the width direction of the track girders 1 and 2, and is attached to the girder receiver 13. The soundproof wall 10 is constituted by a soundproof plate 19 having a sound absorbing material 16 on the side of the track girders 1 and 2, that is, on the upper surface. The soundproof wall 10 is fixed to the girder support 13 and the cable rack 11 directly below the girder. Reference numeral 15 denotes a rising portion of the soundproof wall 10 , which is arranged close to the skirt 6 on the vehicle side.

To explain the soundproofing effect in such a configuration, the track girders 1 and 2 are installed on the girder receiver 13 via the large gel 12, and the tolerance of the level difference between the tracks 1 and 2 is adjusted by using shims in the vertical direction of the large gel 12. Even if it is 3mm
The degree of accuracy is relatively high. Furthermore, the mounting of each finger plate 8, 9, 9' on the girder surface also creates a mounting step with the tire tread, and the running noise of the drive tire 7 is 5 to 7 dB higher at the seam 17. In vehicles that have countermeasures against bogie sound sources, this impact sound dominates the noise. This impact sound is generated every time the drive tire 7 passes the joint 17, and is radiated outside the vehicle through an opening in the skirt 6 or the like on the vehicle side.

The present invention prevents this radiated sound from propagating to the ground side by absorbing and diffracting the radiated sound with a soundproof wall 10 that extends from just below the joint 17 in the longitudinal direction of the track girders 1 and 2, that is, toward the center of the longitudinal direction. It is something to do. The dimension L' of each soundproof wall 10 from the track girder joint to the longitudinal end of the track girder is at least equal to or larger than the distance L between the axes of the drive tires 7 of the bogie 4 . That is, the bogie 4 is surrounded by a plate material having sound absorbing and sound blocking functions, and the sound pressure inside the vehicle interior is high. In particular, the drive tire 7 is connected to the track girder joint 1.
7, the noise becomes louder. Therefore, since the noise propagates to the outside through the gap between the wheel chamber and the track girder, the soundproof wall 10 needs to correspond to the size of the wheel chamber. Therefore, the dimension L' of each soundproof wall 10 in the longitudinal direction of the track girder is set to be at least the distance L between the axes of the drive tires 7,
It is possible to reduce the noise leaking from the wheel chamber to the lower part of the track girder within the range of one bogie. In addition to the fact that the width of the lower surface of the track girders 1 and 2 is expanded and the shade from the track becomes larger, the soundproof wall 10 is used because the front and rear bogies of the vehicle are not at the joint position at the same time, which reduces tire noise. It is. Since the upper surface of the soundproof wall 10 is made of sound absorbing material 16, there is a possibility that rainwater may enter the wall.Therefore, a fibrous material is avoided and an aluminum sintered alloy or a porous material is used instead. Further, since the end face is provided with the rising portion 15, the diffraction effect of the radiated sound is high, and propagation to the ground side can be reduced.

Furthermore, the longitudinal dimension of the track girder of each soundproof wall 10
By setting L' to be at least the distance L between the axes of the drive tires 7, it is possible to efficiently prevent the noise caused by the track girder joints 17 from propagating downward to the track girder without making the soundproof wall 10 large. It can be prevented. As a result, the structure of the soundproof wall 10 itself can be simplified, the range where solar radiation is obstructed can be narrowed, and the track girder itself can be prevented from being degraded. Further, since the soundproof wall 10 is mainly supported by the girder supports 13, the support structure and the like can also be simplified.

〔Effect of the invention〕

As explained above, according to the present invention, on the elevated track on which the straddle type monorail vehicle runs,
Of the noise generated from the track girder joint, the noise transmitted to the ground can be reduced, the structure can be simplified, and solar radiation obstruction can be prevented.

[Brief explanation of the drawing]

Fig. 1 is a side view showing the track girder near the support column equipped with the present invention, Fig. 2 is a partial detailed view showing the relationship between the girder holder of the support column and the soundproof wall, and Fig. 3 is a cross section taken along the line A-A in Fig. 2. It is a diagram. 1, 2... Track girder, 4 ... Bogie, 5... Support column,
6... Skirt, 7... Drive tire, 10 ... Soundproof wall, 13... Girder holder, 15... Rising part, 16
...Sound absorbing material, 17...Seam.

Claims (1)

[Scope of Claims] 1. In a soundproof wall of a monorail track in which a joint portion of a track girder on which a straddle type monorail vehicle runs is supported by a girder receiver, from the upper part of the girder receiver to the longitudinal center of each track girder and the track girder. A soundproof wall extending in the width direction is installed on the girder receiver, and the dimension of each soundproof wall from the track girder joint side to the longitudinal end of the track girder is at least longer than the distance between the axes of the vehicle bogie, and A soundproof wall for a monorail track, characterized in that each of the soundproof walls is made of a soundproofing material having a sound absorbing material provided on the upper surface. 2. A soundproof wall for a monorail track according to claim 1, characterized in that a rising portion is provided at an outer peripheral end of the soundproof wall.