JP6889636B2 - Railroad vehicle - Google Patents

Description

The present invention relates to a railway vehicle that reduces in-vehicle noise.

In high-speed railway vehicles, it is indispensable to reduce the noise in the passenger compartment, which has increased with the increase in speed. Sounds generated by the running of railroad vehicles include aerodynamic sounds from current collectors, rolling sounds generated between wheels and rails, and driving sounds of electrical equipment. The frequencies of the sounds generated from each sound source are different, and these sounds overlap to form noise inside the vehicle. In order to reduce such in-vehicle noise, various in-vehicle noise reduction technologies have been developed.

As a noise countermeasure for high-speed railway vehicles, there is a technique disclosed in, for example, Patent Document 1 in order to reduce the air propagating sound transmitted from the outside of the vehicle to the inside of the vehicle. In this known example, "a plurality of fine holes (sound absorbing holes) are formed on the inner surface plate of the extruded hollow profile constituting the vehicle structure, for example, having a diameter of about 0.1 to 1 mm and a hole spacing of about 3 mm. Regarding the extruded hollow profile that constitutes the vehicle structure, the inner surface plate that is a part of it becomes a fine perforated plate with a plurality of micropores, and the interior plate that is arranged through the space between the inner surface plate is the sound insulation plate. "Structures that are configured to function as" are disclosed.

Japanese Patent No. 5160664

According to the disclosure of Patent Document 1, it is said that a sound absorbing effect can be expected without using a sound absorbing material due to the structure provided with micropores. However, even if a large number of holes are provided in the inner surface plate of the extruded hollow profile used for the vehicle structure, the transmission loss of the air propagating sound can be reduced, or the rib connecting the outer surface plate and the inner surface plate can be propagated. It is difficult to reduce the incoming solid-borne sound. In addition, when noise in the low frequency band is generated due to the vibration mode of the entire vehicle structure, the outer surface plate, ribs, and inner surface plate vibrate together to emit radiated sound, so it is provided on the inner surface plate. The sound absorbing effect cannot be expected from the fine pores. On the other hand, when the interior plate is provided with micropores, a Helmholtz resonator is formed by the inner surface plate of the extruded hollow profile, the interior plate, and the air layer between them. In this case, the inner surface plate and the interior plate vibrate in the same phase. Therefore, the intended noise reduction effect cannot be expected.

An object of the present invention is to reduce the noise level of a railway vehicle by using a sound absorbing structure having a perforated space and a closed space.

In order to solve the above problems, one of the representative railway vehicles of the present invention is a railway vehicle having an interior space composed of a ceiling panel, a window, a side panel, an upper floor, and a seat.
Wherein the seat is provided a perforated plate formed with perforations, the sound absorbing structure having a closed space which communicates with the external space via the perforations Rutotomoni,
This is achieved by providing the sound absorbing structure so that a closed space is formed by the window and the side panel.

According to the present invention, by arranging the perforated plate of the sound absorbing structure so as to face the space where the sound pressure in the vehicle is high, the effect of reducing the noise in the vehicle can be obtained.
Issues, configurations and effects other than those described above will be clarified by the description of the following embodiments.

It is the schematic of the railroad vehicle cabin which concerns on embodiment of this invention. It is the schematic of the sound absorbing structure which concerns on embodiment of this invention. It is the schematic which arranged the sound absorbing structure which concerns on Embodiment 1 of this invention inside a seat. It is the schematic which arranged the sound absorbing structure which concerns on Embodiment 2 of this invention parallel to a window. It is the schematic which arranged the perforation plate which concerns on Embodiment 3 of this invention parallel to a window. It is the schematic which applied the structure of the sound absorbing structure which concerns on Embodiment 4 of this invention to a luggage rack. It is the schematic which arranged the sound absorbing structure which concerns on Embodiment 5 of this invention around a seat. It is the schematic of the slide type sound absorption structure which concerns on Embodiment 6 of this invention. It is a schematic diagram of the partition type sound absorption structure which concerns on Embodiment 7 of this invention. It is the schematic of the concavo-convex perforated type sound absorption structure which concerns on Embodiment 8 of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the present specification, a structure in which the perforated plate and the air layer behind the perforated plate are closed spaces is hereinafter referred to as a "sound absorbing structure". Further, the closed space means an internal space shielded by a perforated plate and other members with respect to the external space of the sound absorbing structure.
Further, the portion that connects the external space of the sound absorbing structure and the closed space inside is called a neck portion.

FIG. 1 is a schematic view of the inside of a railroad vehicle cabin according to the embodiment of the present invention. The interior 1 shown in FIG. 1 is composed of a ceiling panel 2, a luggage rack 3, a window 4, a side panel 5, an upper floor 6, and a seat 7. Further, the noise inside the vehicle is a sound in which the radiated sounds from the ceiling panel 2, the window 4, the side panel 5, and the upper floor 6 are overlapped, and is a noise including a frequency component in a wide band from low frequency to high frequency.

(Embodiment 1)
FIG. 2 is a schematic view of a sound absorbing structure according to an embodiment of the present invention. FIG. 2A shows the appearance of the sound absorbing structure 8, and FIG. 2B shows a cross section taken along the line AA of FIG. 2A. The sound absorbing structure 8 applies the principle of the Helmholtz resonator. The sound absorbing structure 8 is surrounded by four wall plates 8c between a perforated plate 8b provided with a plurality of perforated perforations 8a and a wall plate 8c which is a bottom plate having no perforations facing the perforated plate 8a, and the inside thereof. It has a housing shape with a closed space of 8d.

When a sound wave enters the perforation 8a from the outside of the sound absorbing structure 8, the air in the closed space 8d acts as a spring, and the air in the perforation 8a serving as the neck vibrates as one mass. In particular, when a sound wave having a frequency corresponding to the resonance frequency of the sound absorbing structure is incident, the air in the neck portion vibrates violently, and a large sound absorbing function due to friction loss is exhibited. Further, since the resonance frequency is a function of the cross-sectional area of the perforation 8a, the volume (volume) of the closed space 8d, and the length of the neck portion of the perforation 8a, it is expected that the noise reduction effect in a specific frequency band can be expected by adjusting these. it can.

FIG. 3 is a diagram showing a state in which the sound absorbing structure according to the first embodiment of the present invention is arranged inside the seat. FIG. 3 shows a front view (3a), a right side view (3b), a plan view (3c), and a bottom view (3d). With reference to FIG. 1, in the passenger compartment 1 of a railcar, the sound pressure is large in the space between the seat 7 and the luggage rack 3, the seat 7 and the window 4, the seat 7 and the side panel 5, and the seat 7 and the upper floor 6. Since these spaces are relatively close to the ears of seated passengers, they are easily recognized as noise. Considering the noise environment peculiar to the passenger compartment of this railway vehicle, it is effective to use a railway vehicle having a sound absorbing effect on the seats.

As shown in FIGS. 3A and 3C, the sound absorbing structure 8 is installed inside the upper part of the seat back of the seat 7 (near the head of the seated passenger), and the perforation 8a is provided on the ceiling panel 2 (see FIG. 1). By turning to the side, the sound pressure between the seat 7 and the ceiling panel 2 and between the seat 7 and the luggage rack 3 (see FIG. 1) is reduced. Further, as shown in FIG. 3B, the sound absorbing structure 8 is installed inside the seat back of the seat 7, and the perforation 8a is directed toward the window 4 (see FIG. 1), whereby between the seat 7 and the window 4. Sound pressure is reduced.

Further, as shown in FIGS. 3A and 3B, the sound absorbing structure 8 is installed in the seat cushion of the seat 7, or the sound absorbing structure 8 is installed in the space between the seat 7 and the upper floor 6 to make a perforation 8a. Is directed toward the side panel 5 (see FIG. 1), so that the sound pressure between the seat 7 and the side panel 5 is reduced. Further, as shown in FIGS. 3A and 3D, the sound absorbing structure 8 is installed in the seat cushion of the seat 7, and the perforation 8a is directed toward the upper floor 6 (see FIG. 1) to form the seat 7 and the seat 7. The sound pressure between the upper floors 6 is reduced.

(Embodiment 2)
FIG. 4 is a diagram showing a state in which the sound absorbing structure according to the second embodiment of the present invention is arranged parallel to the window. In the sound absorbing structure of the present embodiment, the shielding position that shields the window 4 (not shown) and the sound absorbing structure that moves the sound absorbing structure in parallel with the window surface (not shown) are placed between the window 4 and the position that does not overlap (not shown) (vertical direction or). It can slide (in the front-rear direction of the vehicle). The sound absorbing structure of the present embodiment has a structure that functions as a thin housing-like blind, and the perforated plate 8b is arranged with the perforated 8a facing the window side. The axis of the perforation 8a is preferably parallel to the normal of the window 4. As a result, the wave of radiated sound propagating from the window 4 near the passenger's ear is incident on each of the perforations 8a in parallel, so that the sound absorbing effect is large and the sound pressure level near the passenger's ear is reduced.

(Embodiment 3)
FIG. 5 is a view showing a state in which the perforated plate of the sound absorbing structure according to the third embodiment of the present invention is arranged parallel to the window. The sound absorbing structure of the present embodiment is composed of a plate-shaped perforated plate 8b that also serves as a blind, a side panel 5 provided around the plate-shaped perforated plate 8b, and a window 4. The perforated plate 8b is movable, and has a separation position (not shown) separated from the opening of the side panel 5 facing the window 4 and a shielding position (not shown) that is fitted into the opening to shield the window 4. It is possible to slide between them (in the vertical direction or in the front-back direction of the vehicle). By using the perforated plate 8b as such a blind, the closed space 8d is formed by the window 4 and the side panel 5. According to this embodiment, it is not necessary to provide a side plate, and the sound pressure level between the seat 7 (see FIG. 1) and the window 4 is reduced by a simple sound absorbing structure using the conventional structure.

(Embodiment 4)
FIG. 6 is a diagram showing a state in which the structure of the sound absorbing structure according to the fourth embodiment of the present invention is applied to a luggage rack. The luggage rack 9 shown in FIG. 6 can be used as a modification of the luggage rack 3 shown in FIG. 1, and here, since it is necessary to support a heavy object such as luggage, it has a housing shape including a truss structure. .. The luggage rack 9 as a truss-type sound absorbing structure includes a perforation 9a provided on the ceiling panel 2 side and a seat 7 side, a pair of perforation plates 9c provided with a plurality of the perforations 9a, a pair of perforation plates 9c, and a truss. It is composed of a plurality of closed spaces 9b partitioned by. With such a configuration, the sound pressure between the ceiling panel 2 and the luggage rack 9 and between the luggage rack 9 and the seat 7 is reduced by the same effect as that of the above-described embodiment. The perforations 9a need only be provided on the ceiling panel 2 side and at least one of the seats 7.

(Embodiment 5)
FIG. 7 is a diagram showing a state in which the sound absorbing structure according to the fifth embodiment of the present invention is arranged around the seat, and shows an example in which the above-described first to fourth embodiments are combined. More specifically, by installing the sound absorbing structure 8 inside the upper part of the seat back of the seat 7 and directing the perforation 8a toward the ceiling panel 2 (see FIG. 1), the seat 7, the ceiling panel 2, and the seat 7 The sound pressure between the luggage racks 9 can be reduced. Further, by installing the sound absorbing structure 8 inside the seat back of the seat 7 and directing the perforation 8a toward the window side, the sound pressure between the seat 7 and the window 4 can be reduced. Further, by installing the sound absorbing structure 8 inside the seat cushion of the seat 7 and directing the perforation 8a toward the side panel 5, the sound pressure between the seat 7 and the side panel 5 can be reduced. Further, by installing the sound absorbing structure 8 inside the seat cushion of the seat 7 and directing the perforation 8a toward the upper floor 6, the sound pressure between the seat 7 and the upper floor 6 can be reduced. Further, the blind of the window 4 is a sound absorbing structure 8 (or the sound absorbing structure shown in FIG. 5), and the perforation 8a is directed toward the window 4, so that the sound pressure level near the passenger's ear in the normal direction of the window 4 is reached. Can be reduced. Further, by making the luggage rack 9 a truss type sound absorbing structure, the sound pressure between the ceiling panel 2 and the luggage rack 9, and the luggage rack 9 and the seat 7 can be reduced. However, in the sound absorbing structure 8 provided in the seat 7, it is sufficient that the perforation 8a faces at least one of the ceiling panel 2, the window 4, the side panel 5, and the upper floor 6.

By adjusting the volume of the back air layer, the number of holes, the number of holes, the pitch between holes, the thickness of the hole plate, etc. in the sound absorbing structure, the resonance frequency of the sound waves passing through the holes can be controlled. The effect of reducing noise in the frequency band that contributes greatly can be obtained. Representative examples of these will be specifically described in the embodiments described below.

(Embodiment 6)
FIG. 8 is a diagram used to explain the slide type sound absorbing structure according to the sixth embodiment of the present invention. FIG. 8A shows the appearance of the slide type sound absorbing structure 10, and FIG. 8B shows a cross section taken along the line BB of FIG. 8A. Inside a railroad vehicle, the frequency of the noise level peak value may differ depending on the location. In addition, the frequency of the noise level peak value may differ depending on the traveling section. According to the slide type sound absorbing structure 10 according to the present embodiment, the resonance frequency can be adjusted according to the frequency of the noise level peak value.

More specifically, the slide-type sound absorbing structure 10 has four wall plates 10c surrounding a rectangular perforated plate 10b having a plurality of perforations 10a, and a rectangular shape facing the perforated plate 10b and having no perforations. Four wall plates 10c surrounding the wall plate (also referred to as a bottom plate) 10c are nested and fitted together. By sliding the wall plates 10c that overlap each other relatively in the vertical direction in the figure, the volume of the closed space 10d is changed, thereby adjusting the resonance frequency according to the frequency of the noise level peak value, and the most effective sound absorption. It can be effective. By replacing the sound absorbing structure 8 used in the above-described embodiment with the slide type sound absorbing structure 10, it is possible to use a perforated plate having a uniform perforated diameter regardless of the installation location, and cost reduction can be achieved.

(Embodiment 7)
FIG. 9 is a diagram used to explain the partition type sound absorbing structure according to the seventh embodiment of the present invention. 9 (a) shows the appearance of the partition type sound absorbing structure 11, and FIG. 9 (b) shows the CC cross section of FIG. 9 (a). The partition type sound absorbing structure 11 is a housing structure having a perforated plate 11c having perforations 11a and 11b having different diameters (or sizes) and a wall plate 11d for partitioning a closed space. By combining the closed spaces 11e and 11f having different volumes partitioned by the wall plate 11d and the perforations 11a and 11b having different diameters that communicate these with the external space, a plurality of resonance frequencies can be set. It is possible to effectively reduce the noise in the frequency band of. By replacing the sound absorbing structure 8 used in the above-described embodiment with the partition type sound absorbing structure 11, the noise level in a wide frequency band is reduced. Further, for example, a single partition type sound absorbing structure 11 may be installed inside the seat back of the seat 7 so that the perforations 11a and 11b are directed in different directions, whereby the assembly man-hours and the like can be reduced.

(Embodiment 8)
FIG. 10 is a diagram used to explain the concavo-convex perforated sound absorbing structure according to the eighth embodiment of the present invention. FIG. 10A shows the appearance of the concavo-convex perforated sound absorbing structure 12, and FIG. 10B shows the DD cross section of FIG. 10A. In the concavo-convex perforated sound absorbing structure 12, the perforated space 12d surrounded by the perforated plate 12b and the wall plate 12c and the external space are made into a pipe type perforated 12a. This corresponds to the case where the volume of the closed space 12d cannot be sufficiently secured, and since the resonance frequency is a function of the length of the neck portion, the neck portion is made longer than the plate thickness of the perforated plate 12b. For example, it can be formed by joining a circular tube cut to a predetermined length to the perforated plate 12b. By installing the uneven perforated sound absorbing structure 12 inside the seat cushion of the seat 7 and directing the pipe type perforated 12a toward the upper floor side, the convex portion of the pipe type perforated 12a does not get in the way and the seat 7 and the upper floor 6 (FIG. The sound pressure during (see 1) is reduced. Further, if the pipe type perforation 12a is pulled in and the outer end thereof is flush with the outer surface of the perforation plate 12b, the convex portion disappears, so that it can be used in the same manner as in each of the above-described embodiments. .. Each of the above-described embodiments can also be used in combination with each other.

In contrast to the above embodiments, the perforations do not have to be directed to all high sound pressure spaces (ceiling panels, windows, side panels, spaces facing the upper floor) in the vehicle interior, at least of which. It is enough if it is suitable for one. Further, the cross-sectional shape of the perforation is not limited to a circle, and various shapes such as an ellipse and a rectangle can be adopted, and the cross-sectional area thereof may not be uniform and may change along the axial direction. The present invention is not limited to railway vehicles, but can be applied to aircraft, ships, and the like.

The present invention is not limited to the above-described embodiment, and includes various modifications. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to the one including all the described configurations. Further, it is possible to replace a part of the configuration in one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. .. Further, it is also possible to add / delete / replace a part of the configuration in each embodiment with another configuration.

1 ... Inside the guest room, 2 ... Ceiling panel, 3 ... Luggage rack, 4 ... Window, 5 ... Side panel, 6 ... Upper floor, 7 ... Seat, 8 ... Sound absorbing structure, 9 ... Luggage rack with truss type sound absorbing structure 10, ... Slide type sound absorbing structure, 11 ... Partition type sound absorbing structure, 12 ... Concavo-convex perforated sound absorbing structure

Claims (6)

A railroad vehicle with an interior space consisting of ceiling panels, windows, side panels, upper floors, and seats.
Wherein the seat is provided a perforated plate formed with perforations, the sound absorbing structure composed of a closed space which communicates with the external space via the perforations Rutotomoni,
A railway vehicle characterized in that the sound absorbing structure is provided so that a closed space is formed by the window and the side panel. In the railcar according to claim 1, the seat has the sound absorbing structure whose perforations are directed to at least one side of the ceiling panel, the window, the side panel, and the upper floor. A railroad vehicle featuring. In the railroad vehicle according to any one of claims 1 or 2, the sound absorbing structure is provided on a luggage rack having a truss structure, and the sound absorbing structure is provided on at least one of the ceiling panel side and the seat side. A railroad vehicle characterized in that the perforations are formed so as to face. The railroad vehicle according to any one of claims 1 to 3, wherein the volume of the closed space of the sound absorbing structure is variable, and the resonance frequency is adjusted accordingly. In the railroad vehicle according to any one of claims 1 to 4, the sound absorbing structure has the perforations having different cross-sectional areas and the closed spaces having different volumes, and a plurality of combinations thereof may be used. A railroad vehicle characterized by having a resonance frequency. The railway vehicle according to any one of claims 1 to 5, wherein the neck portion of the perforation is made longer than the thickness of the perforation plate provided with the perforation.

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