JPH07177606A - Low aerodynamic noise current collector - Google Patents

Abstract

PURPOSE:To provide a current collector in which aerodynamic noise can be suppressed at the time of running. CONSTITUTION:A pantograph comprises two collector shoes 7, and a substantially T-shaped support 9 therefor the collector shoe 7 touches a stringing (not shown) at th.e time of running to collect power and a long hollow body having square cross-section is covered, on the surface thereof, with a metal mesh M. The metal mesh M is composed of strands of SUS 304 and welded to the surface of the hollow body. Multiple miroprotrusions are provided on the surface of the support 9. The microprotrusions 12 are formed by coating the surface of the support 9 with a paint admixed with sand having particle size of 1-2mm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current collector provided on a moving body such as a railroad vehicle that moves at high speed, and more specifically to a low aerodynamic noise current collector capable of suppressing generation of aerodynamic noise during traveling. Regarding the device.

[0002]

2. Description of the Related Art In recent years,
In the problem of outside-vehicle noise of a railway vehicle that is increasing in speed, the problem of noise generated around the vehicle (around the vehicle) is greater than the noise generated between the wheel and the rail. In particular, on a line where a soundproof wall is installed as a noise countermeasure, noise generated by an upper part of the vehicle body and devices around the vehicle body that cannot be covered with the soundproof wall and are exposed becomes a problem.

Of these, the current-collecting system noise generated from the current-collecting device is the most important and needs the most countermeasures from the viewpoint of the function and the performance. Some of the noise in this collector system is
There are spark noises caused by wire breaks and sliding noises generated between the overhead wire and the sliding plate, but as the vehicle speed increases, the noise is generated when the airflow passes around each part of the current collector. Aerodynamic noise becomes a big problem.

As a measure for reducing the aerodynamic noise, streamlining the current collector itself has been considered, and for example, the development of a so-called wing type pantograph has been attempted. However, in this case, although there is an effect of reducing noise by streamlining, it is difficult to secure performance such as aerodynamic stability as a current collector. That is, in the airfoil pantograph, there is a problem in that when the relative angle between the streamlined portion and the surrounding airflow changes, a drastic change in aerodynamic characteristics such as lift change occurs. Therefore, the wing type pantograph has not yet been put to practical use.

As another measure, a panto cover is provided to reduce the flow velocity of the air flow hitting the pantograph. However, when the speed of the vehicle exceeds a certain level, noises are generated from the cover itself and running resistance of the vehicle increases due to the installation of the cover.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a current collector capable of suppressing the generation of aerodynamic noise during traveling.

[0007]

According to the invention of claim 1 for achieving the above object, an electric power supply provided outside the outer surface of a moving body moving at high speed is provided outside the moving body. In a current collector including a current collector that collects electric power from the body and a support that supports the current collector, air flow separation occurs on each surface of the current collector and / or the support. A gist of a low aerodynamic sound collector is characterized in that a surface of a portion to be formed has a net-like structure.

According to the second aspect of the present invention, there is provided a current collecting portion which is provided so as to project from the outer surface of the moving body moving at a high speed to the outside and collects electric power from a power supply body provided outside the moving body. In a current collector including a supporting portion that supports the current collecting portion, minute unevenness is provided on a surface of a portion where airflow separation occurs on each surface of the current collecting portion and the supporting portion. The gist is a low aerodynamic sound collector.

According to a third aspect of the present invention, there is provided a current collecting portion, which is provided so as to project outward from an outer surface of the moving body which moves at a high speed, and which collects electric power from a power supply body provided outside the moving body. A low aerodynamic sound current collecting device, characterized in that the current collecting part and / or the supporting part is formed of a mesh in a current collecting device comprising a supporting part supporting the current collecting part.

According to a fourth aspect of the present invention, there is provided a current collecting portion which is provided so as to protrude from an outer surface of the moving body which moves at a high speed, and which collects electric power from a power supply body which is provided outside the moving body. In a current collector including a supporting portion that supports the current collecting portion, among the members that form the current collecting portion and / or the supporting portion, a member in which airflow separation occurs is covered with a streamline cover. The gist is a low aerodynamic sound current collecting device characterized in that.

Here, the moving body moving at high speed is
It moves at a speed at which aerodynamic noise is generated during the movement, and more specifically, for example, railway vehicles such as magnetic levitation railways and rail type railways, but are not particularly limited to these. is not. The part where the separation of the airflow occurs is a part where the airflow flowing along the surface of each part is separated from the surface in the middle (so-called separation occurs), for example, a corner part provided in the current collector or the support part. And steep curved surface parts.

When the surface of the area where the peeling occurs has a net-like structure, the surface may be covered with a mesh such as a metal mesh, or the surface itself of the area may be formed by the mesh. Good. When the surface is covered with a mesh body, for example, a mesh body such as a metal mesh may be fixed to the surface of each part by welding or adhesion. In addition, if the mesh is partially fixed by spot welding, or is tied to a member with a wire and fixed so that the surface and the mesh are floated as much as possible, the effect of suppressing aerodynamic noise is further enhanced. It is preferable because it improves.

The shape of the minute irregularities is not particularly limited, but for example, minute protrusions (projections) having a height of about 1 to 2 mm may be provided on the surface, or dimples on the surface of a golf ball. A minute recess having a depth of about 2 to 5 mm may be provided. In the case of providing the minute protrusions, for example, a pin may be provided on the surface or a coating material containing particles having an appropriate particle diameter (for example, sand particles) may be applied. When providing these minute irregularities, the irregularities may be arranged regularly (in a row) or may be provided randomly (that is, the distance between the irregularities may be random). Good.

As each member covered by the streamline cover, there may be mentioned, for example, a member constituting a movable part (for example, a supporting device for a current collecting boat, a horizontal link mechanism, etc.) which is necessary for the function of the current collecting device.

[0015]

[Operation] As a mechanism for generating aerodynamic noise in a moving body,
The following two can be theoretically considered. As shown in FIG. 7 (a), the concave portion 1 perpendicular to the air flow
At 01, a cavity resonance sound is generated by the resonance of the pressure wave having a wavelength of ¼ of the depth of the recess.

As shown in FIG. 7B, the corner 103
At the (or a steep curved surface portion), the airflow flowing along the surface causes separation, which causes vortices to generate separation noise. The present invention suppresses particularly peeling noise among the above aerodynamic noises. In the invention of claim 1, the surface has a net-like structure. By providing unevenness, the separation of the air flow is suppressed, the vortex generated by the separation of the air flow is absorbed, and the re-adhesion of the generated separation is promoted, thereby suppressing the generation of separation noise. is there.

Further, particularly when a net-like structure is formed by covering the surface with a net-like body, if the space is provided between the surface and the net-like body as described above, air flows through the gap between the surface and the net-like body, Separation of air flow is suppressed more effectively,
Furthermore, since the generation of minute vortices and the turbulence of the air flow vibrate the net, the energy of aerodynamic sound is converted into the vibration energy of the net, and further converted into heat to be radiated. Therefore, the generation of the vortex that is the sound source is effectively suppressed, and the generation of the peeling sound is further suppressed.

Further, when minute irregularities are provided on the surface, in particular, minute separation of the air flow is promoted, so that the generated vortices become small and the generation of aerodynamic noise can be suppressed. Furthermore, when minute unevenness is randomly provided on the surface by applying paint mixed with particles, etc., periodic vortices generated from the surface of each part are periodically suppressed, and the generation of peeling noise is suppressed. You can

Further, in the invention of claim 3, since the current collecting portion and the supporting portion are formed of a mesh body, the generation of aerodynamic noise is suppressed as in the invention of claim 1, and
Even when the current collecting portion and the support portion are formed in a streamlined shape to reduce aerodynamic noise, the aerodynamic characteristics do not drastically change during traveling, and aerodynamic stability is not impaired. That is, claim 3
In the invention of claim 1, even when the relative angle (angle of attack) between the streamlined current collecting portion or the supporting portion and the surrounding airflow changes during traveling, the airflow passing through the permeation through the mesh body. By doing so, it is possible to suppress a sudden change in aerodynamic characteristics such as lift variation and to eliminate instability due to movement of the separation point (point where separation starts).

Further, according to the fourth aspect of the present invention, by providing a streamline cover for covering the member of the current collector and the support that causes separation of the airflow, the airflow is prevented. The air flow can be rectified to reduce the air resistance, and the airflow can be prevented from hitting the respective members to suppress the generation of aerodynamic noise. Therefore, it is possible to suppress generation of aerodynamic noise even in a portion where it is difficult to form a net-like structure on the surface or to provide minute irregularities.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. First, the first embodiment will be described. Here, FIG. 1 is a perspective view showing a pantograph of the first embodiment, and FIG. 2 is a perspective view showing the pantograph in a partially disassembled state.

As shown in FIG. 1, a pantograph (current collector) 1 of the first embodiment is provided so as to project on a roof 3a of a car body 3 of a railway vehicle, and is fixed on the roof 3a. On the frame 5 (shown by a chain double-dashed line), two current collecting boats 7 and a substantially T-shaped current collecting boat support 9 that supports the current collecting boats 7 are provided.

The current collecting boat 7 is for contacting with an overhead wire (not shown) to collect electric power during traveling.
As shown in the sectional view A, a long hollow body 1 having a square cross section 1
On the upper part of 0, there is provided a sliding plate 10a that comes into contact with an overhead wire to collect current. The surface of the hollow body 10 is (sliding plate 1
The entire surface (except the part where 0a is attached) is covered with the metal mesh M. The metal mesh M is a woven wire mesh made of SUS304 (woven wire mesh), and is fixed to the surface of the hollow body 10 by welding. As the metal mesh M, the wire diameter is about 0.19 to 0.56 mm, the opening (the size of one inner side of the mesh) is about 0.44 to 1.56 mm, and the roughness is # 24.
~ # 36 are used.

Next, as shown in FIG. 2, the current collecting boat support 9 (hereinafter referred to as the support 9) is formed in a substantially T shape by a pipe member having a substantially circular cross section, and the frame 5 It is connected to the tip portion 11a of the lower support 11 that is rotatably attached to the. A large number of minute projections 12 are provided on the surface of the support 9. The fine projections 12 are formed by applying a paint containing sand particles having a particle size of about 1 to 2 mm on the surface of the support 9.

A streamlined cover 15 is provided at an intermediate portion of the side portions 13 extending to the left and right sides of the support 9, and the inside of the cover 15 is as shown in the sectional view of FIG. Further, a shock absorber (supporting device) 17 to which the current collecting boat 7 is attached is provided. This shock absorber 17 includes two moving members 2 to which the current collecting boat 7 is attached to a guide member 19 having an inverted T shape in a side view, which is fixed to the side portion 13 of the support body 9.
1 is provided. The moving member 21 is supported by a coil spring 23 and is elastically movable in the vertical direction. The current collecting boat 7 is attached to an upper end portion 21 a of the moving member 21 projecting outside the cover 15. To be
Therefore, the current collecting boat 7 is interlocked with the moving member 21 to move up and down 3
A stroke of about 0 mm is possible.

As shown in FIG. 1, a pantograph cover 40 is provided around the pantograph 1 to reduce the flow velocity of the air flow hitting the pantograph 1. Further, on the frame 5 fixed on the roof 3a, a spring device and a cylinder (not shown) for driving the support body 9, the lower support body 11 and the like to raise and lower the current collecting boat 7. Etc. are provided.

Next, an example of an experiment carried out to confirm the effect of suppressing the aerodynamic sound by the pantograph 1 will be described. <Experimental example> In a semi-anechoic chamber, the wind speed is 75 from the outlet.
An air flow of about m / s was blown against the target member, and the aerodynamic sound generated from this target member was measured with a microphone. The following three types were used as target members.
In addition, the following first and second embodiments have the configuration described in the first embodiment.

Example 1 A metal mesh (aperture 2 mm, wire diameter 1 mm) made of aluminum was wound around the entire surface of a cylindrical pipe having a diameter of 22 mm. Example 2: The same cylindrical pipe as in Example 1 described above was coated with a paint (mixed with sand particles having a particle size of about 1 to 2 mm) to form minute projections on the surface.

Comparative Example: The same cylindrical pipe as that used in Example 1 above (no metal mesh or fine protrusions are provided on the surface). FIG. 5 is a graph showing the measurement results of the above experiment. As is clear from this result, particularly in the region where the 1/3 octave band frequency is about 400 Hz or more, the example 1 in which the surface is covered with the metal mesh and the example 2 in which the minute projections are provided on the surface are comparative examples. It was found that the power level (dBA) of the aerodynamic sound was smaller than that of the above, and the generation of the aerodynamic sound was suppressed.

As described in detail above, in the pantograph 1 according to the first embodiment, the surface of the current collecting boat 7 having a square cross-section which easily causes separation of the air flow is covered with the metal mesh M, and the air is also removed. By providing the minute projections 12 on the surface of the support 9 where flow separation easily occurs, a remarkable effect of suppressing aerodynamic noise (separation sound) generated at these portions is achieved.

Particularly, in order to optimize the aerodynamic stability (for example, lift variation) required of the pantograph, the current collecting boat 7 is preferably a rectangular cross section (like the square shape in the above embodiment). However, it was difficult to suppress the aerodynamic noise by forming the streamline shape, but by covering the surface with the metal mesh M as in the present embodiment, the current cross-sectional shape of the current collecting boat 7 is changed. There is an advantage that it is possible to take countermeasures against aerodynamic noise without (that is, without streamlining).

Further, in the above embodiment, since the shock absorber 17 to which the current collecting boat 7 is attached is covered by the streamlined cover 15, the air resistance during traveling is reduced and the aerodynamic noise generated by the shock absorber 17 is reduced. This is effective in preventing (peeling sound) from being generated. That is, this shock absorber 1
For a movable mechanism such as 7, it is difficult to provide a metal mesh or minute irregularities on individual members (moving member 21, coil spring 23, etc.), but as in the embodiment, the streamline cover 1 is used.
By covering with 5, it is possible to prevent the generation of aerodynamic noise without providing a metal mesh or minute irregularities.

Further, in this embodiment, since the current collecting boat 7 and the support 9 which are exposed to a relatively high flow velocity during traveling have a simple structure, there is an advantage that aerodynamic noise is hard to be generated. . In the pantograph 1 of the first embodiment, the current collecting boat 7 or the support 9 itself may be formed of a metal mesh so that the whole structure has a mesh structure.

Further, a net-like body or fine irregularities may be provided on the surface of the portion other than the collector boat 7 and the support 9 (for example, the frame 5 and the lower support 11). The conditions such as the roughness and thickness of the metal mesh provided or the size of the minute protrusions may be appropriately adjusted according to the level of aerodynamic noise generated at that portion.

Next, the second embodiment will be described. Figure 6
As shown in, the airfoil pantograph 41 of the second embodiment is
The whole is formed in a streamlined shape in order to prevent separation of the airflow, and a substantially elliptical wing-shaped current collector 45 provided with the sliding plate 43 similar to the first embodiment, and a vehicle body (not shown) Wing-shaped support part 4 which is hung vertically on the roof of and supports the current collecting part 45.
7 and 7. Here, the current collector 45 is shown in FIG.
As shown in the sectional view of 1., the whole is formed of the same metal mesh M as that of the first embodiment, and the inside thereof is hollow. That is, the current collector 45 has the metal mesh M around the outside of the cage-shaped strength member 49 as shown in FIG. 6C.
Is fixed to form a streamlined shape (wing shape). Therefore, the air flow around the current collector 45 (see FIG.
Part of (indicated by an arrow in (b)) will pass through the metal mesh M.

Therefore, according to the airfoil pantograph 41 of the second embodiment, since the current collecting portion 45 and the support portion 47 are formed in a streamlined shape, separation of the air flow does not occur, and separation occurs. The effect is that no sound is generated. Also,
Even if air flow separation occurs, the current collector 45 itself is formed of the metal mesh M (the surface has a mesh structure), and therefore the separation noise is suppressed. Further, according to the airfoil pantograph 41, the aerodynamic characteristics of the current collector 45 do not greatly change during traveling,
This has the effect of maintaining aerodynamic stability. That is, FIG.
As shown in (b), even if the relative angle (angle of attack α) between the current collector 45 and the surrounding air flow becomes large during traveling, the air flow passes through the metal mesh M, This has the effects of suppressing abrupt changes in aerodynamic characteristics such as increased lift, and eliminating aerodynamic instability due to movement of the separation point (the point where airflow separation begins). Although the embodiments have been described above, the present invention is not limited to the above embodiments and can be implemented in various modes.

For example, the streamlined cover 15 of the first embodiment.
May be formed by a mesh body such as a metal mesh. By doing so, there is an effect that the aerodynamic stability during traveling is not deteriorated, as in the case of the wing type pantograph 41 of the second embodiment. Further, the shape of the current collector to which the present invention is applied is not limited to the above-mentioned embodiment, and various shapes can be applied.

Further, the material of the reticulate body used in the present invention is not limited to SUS304 as in the above embodiment, but other metal such as aluminum or synthetic resin may be used.

[0039]

As described above, according to the low aerodynamic sound collector of claim 1 of the present invention, the surface of the portion where the airflow separation occurs has a net-like structure, so that the airflow separation occurs. It is possible to suppress the generation of aerodynamic noise (peeling sound) due to, and it is possible to greatly contribute to solving the noise problem.

Further, according to the invention of claim 2, by providing minute irregularities on the surface of the portion where the separation of the air flow occurs, the generation of aerodynamic noise due to the separation of the air flow is achieved as in the invention of claim 1. There is an effect that it can be suppressed. Further, according to the invention of claim 3, by forming the current collecting portion and the supporting portion with a mesh body, even if the current collecting portion and the supporting portion are formed in a streamlined shape in order to reduce aerodynamic noise, running There is an effect that the aerodynamic stability does not change while the aerodynamic characteristics do not change rapidly.

Further, according to the invention of claim 4, by providing the streamline cover for covering the member where the separation of the airflow occurs, the airflow is rectified to reduce the air resistance, and at the same time, the airflow is applied to each member. There is an effect that the flow can be prevented and the generation of aerodynamic noise can be suppressed.

[Brief description of drawings]

FIG. 1 is a perspective view showing a pantograph of a first embodiment.

FIG. 2 is a perspective view showing a partially exploded pantograph of the first embodiment.

FIG. 3 is a cross-sectional view showing a current collecting boat of the first embodiment.

FIG. 4 is a cross-sectional view showing a streamlined cover and a shock absorber of the first embodiment.

FIG. 5 is a graph showing the effect of suppressing aerodynamic noise in the pantograph of the first embodiment.

FIG. 6 shows an airfoil pantograph of a second embodiment, (a)
Is a perspective view thereof, (b) is a cross-sectional view of the current collector, and (c) is a perspective view showing a strength member inside the current collector.

FIG. 7 is an explanatory diagram for explaining the operation of the present invention.

[Explanation of symbols]

1 ... Pantograph 7 ... Current collecting boat 9 ... Current collecting boat support 12 ... Micro projection 15 ... Cover 17 ...
Shock absorber M ... Metal mesh

Claims (4)

[Claims] 1. A current collector that projects outward from an outer surface of a moving body that moves at high speed and collects power from a power supply body that is provided outside the moving body, and supports the current collecting unit. A low aerodynamic sound, characterized in that, in the current collector including the supporting portion, the surface of each portion of the current collecting portion and / or the supporting portion where airflow separation occurs has a net-like structure. Current collector. 2. A current collector that projects outward from an outer surface of a moving body that moves at high speed and collects power from a power supply body that is provided outside the moving body, and supports the current collecting portion. A low aerodynamic current collector, characterized in that, on the surface of each part of the current collecting part and the supporting part, minute unevenness is provided on the surface of the part where airflow separation occurs. apparatus. 3. A current collecting part, which is provided so as to project from the outer surface of a moving body moving at a high speed to the outside and collects electric power from a power supply body provided outside the moving body, and supports the collecting part. In the current collecting device, the current collecting part and / or the supporting part is formed of a mesh body. 4. A current collector that projects outward from an outer surface of a moving body that moves at high speed and collects power from a power supply body that is provided outside the moving body, and supports the current collecting unit. A low aerodynamic force, characterized in that among the members constituting the current collector and / or the support, a member in which airflow separation occurs is covered with a streamline cover. Sound collector.