JPS5817067B2 - Tetsudoshi Yariyou no Bou On Souchi - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a soundproofing device for a railway vehicle that can efficiently reduce noise generated by a running railway vehicle.

It is well known that as interest in various types of noise pollution increases, development of soundproof walls and the like to reduce these noises is progressing.

Since noise varies depending on the source, environment, etc., it is extremely difficult to eliminate all noise.
Common noise countermeasures include installing a barrier such as a soundproof wall between the sound source and the sound receiving side to block the propagation of sound, or completely surrounding and shielding the sound source.

However, it goes without saying that the former type of barrier has a limited soundproofing effect, and the latter type of barrier is difficult to implement considering other requirements such as heat and exhaust.

To take a concrete example, soundproof walls are currently mainly used to counter train noise generated by the running of vehicles such as Shinkansen trains, but the sound reduction effect is limited to about 20 dB, especially in areas where the sound source can be seen. In this case, the effect of the soundproof wall is hardly obtained, and even if the height of the east soundproof wall is raised above a certain level to make it impossible to see through, the soundproofing effect will not be significantly improved.

In order to solve this problem, it may be possible to adopt a single shelter system that completely encloses the entire length of the route, but this has the disadvantage that it is not possible when considering sunlight, cost, ventilation, and psychological effects on passengers.

Therefore, in order to solve the above-mentioned problems, the present invention provides a soundproofing device for a railway vehicle that employs a soundproofing wall and can more efficiently reduce railway noise.

Railway noise consists of upper noise such as noise between wheels and rails, sliding noise of pantographs, noise from drive equipment and auxiliary equipment, and noise generated by vibration of vehicle side panels, and lower noise related to structural noise of soundproof walls and viaducts. There is.

Among these noises, the noise between the wheels and the rails is the loudest.

Therefore, if this noise is prevented from propagating beyond the soundproof wall, it can be expected that the sound reduction effect will be efficiently improved.

This invention provides a sound wave control device for generating noise, which has at least its tip extending downward from a line connecting the contact portion between the rail and the wheel and the upper end of the soundproof wall, and which is capable of controlling the direction of noise propagation downward. To provide a vehicle that can significantly reduce the propagation of the main noise generated between the wheels and the rails beyond the soundproof wall by installing the noise source near the wheels, which are the source of the noise.

The sonic wave control device referred to in this specification refers to, for example, Japanese Patent Application No. 50-6413 (Japanese Unexamined Patent Publication No. 51-8) previously filed by the present applicant.
2923) and Japanese Patent Application No. 50-36304 (Japanese Patent Application No. 50-36304)
1-111301), and the outline of its configuration is as shown in FIGS. 5 and 6.

The structure of the present invention will be described in detail with reference to the embodiment shown in the drawings. In FIGS. 1 and 2, 4 is a soundproof wall installed along both sides of the viaduct 8, and the noise generated between the rail 2 and the wheels 3 is This is a device that has been used in the past to shield noise from driving equipment and attached equipment.

In this case, the region X above the soundproof wall 4 is a free propagation space for sound, so almost no sound reduction effect can be obtained, and even in the region Y behind the soundproof wall 4, the noise that has passed over the top of the soundproof wall 4 is diffracted. Free propagation results in a much lower sound reduction effect than expected.

Therefore, the present invention is devised so that the noise generated from the contact area between the rail 2 and the wheels 3 of the vehicle 5, which is the main noise source, propagates intensively to the soundproof wall 4. The lower end is equipped with a sonic wave control device 1.

In this case, the tip of the sonic control device 1 is connected to the rail 2 and the wheel 3.
and the upper end of the soundproof wall 4.

The sound wave control device 1 controls the propagation direction of sound as shown in FIGS. 5 and 6, and the device shown in FIG. The propagation direction of the noise generated from the sound source is controlled by passing it through the hollow passage 10, and the one shown in FIG. The sound propagation direction, that is, the traveling direction of the sound wavefront is controlled by the difference between the acoustic medium density generated within the control device 1 and the medium density around the device.

7 in the figure is a sound absorbing material provided on the soundproof wall 4.

In another embodiment shown in FIG. 3, the sonic wave control device 1 is integral with the side plate 6 of the vehicle 5 and is formed in advance at the lower end of the side plate 6.

In this case, the sonic wave control device 1 has the advantage that it can be made thinner by using a sanitary type device in which the control elements 11 are sequentially increased from the upper row to the lower row as shown in FIG. .

In the illustrated example, the sonic wave control device 1 is installed on the lower end of the side plate 6 of the vehicle 5, but it is of course possible to install it on the truck or the floorboard of the vehicle 5.

According to this invention, the sonic wave control device 1 capable of controlling the propagation direction of noise downward is installed near the wheel 3 that is the source of noise, and its tip is connected to the contact area between the rail 2 and the wheel 3 for soundproofing. Since it is set to extend downward from the line l connecting the upper end of the wall 4, the propagation direction of the noise generated from the noise source is changed by the sound wave control device 1, and the soundproof wall 1
Therefore, the noise passing over the upper part of the soundproof wall 4 is significantly reduced, and a large sound reduction effect can be obtained in the region Y behind the soundproof wall 4.

In this case, if the sound-absorbing material 7 is provided on the soundproof wall 4, the noise directed downward will be absorbed by the sound-absorbing material 7, and reflected noise can be prevented, thereby further promoting the sound reduction effect.

The effects of this invention have been confirmed through experiments and will be explained below.

As shown in Fig. 4a, the sound wave control device 1 and the speaker (
The positional relationship between sound source) S and sound receiving point P is A.

Three types B and C were selected.

That is, A indicates the case where the line connecting the speaker S and the sound receiving point P is below the sonic control device 1, B indicates the case where it touches the upper end of the sonic control device 1, and C indicates the case where the line connecting the sonic control device 1 is above the sonic control device 1. Indicates a certain case.

Sound waves with octave center frequencies of 500 Hz and 1000 Hz were generated from the speaker S, and the sound pressure level at the sound receiving point P was measured when the sound wave control device 1 was installed and when it was removed, and the volume reduction was calculated.

The results are shown in Figure 4. According to this, A and B
If the line connecting the sound source and the sound receiving point is below the sound wave control device or in contact with it, a volume reduction of 10 dB or more can be obtained, whereas the line connecting the sound source and the sound receiving point is under the sound wave control device. It is understood that in the case of C located above the device, the sound reduction effect decreases rapidly.

As described above, the soundproofing device for a railway vehicle of the present invention can dramatically improve the effect of installing a soundproofing wall.

[Brief explanation of the drawing]

1 and 2 show one example of the soundproofing device for a railway vehicle of the present invention, FIG. 1 is a sectional view, FIG. 2 is a partially cutaway side view of the main part, and FIG. 3 is another embodiment. Partial view showing FIG. 4a,
b is an explanatory diagram of an experimental example of the device of the present invention, and FIGS. 5 and 6 are schematic diagrams of the sonic wave control device. 1... Sonic control device, 2... Rail,
3... Wheels, 4... Soundproof walls, 5...
...Vehicle, 6...Side plate.

Claims (1)

[Claims] 1. A sonic wave control device consisting of a plurality of hollow passages that have a sound passage area penetrating from one side to the other and that regulates and changes the direction of sound propagation is installed at the contact area between the rail and the wheels and at the top of the soundproof wall. The sonic wave control device extends from the lower side of the vehicle body so that at least its tip is located below the line connecting The sound emission direction of the hollow passage is changed with respect to the noise propagation direction so that the noise generated from the contact area between the rail and the wheel, which is the main noise source, propagates intensively to the soundproof wall, and A soundproofing device for a railway vehicle, which is characterized by being directed toward.