JPH04133602A - Sound arrestor for pantograph - Google Patents

Abstract

PURPOSE:To reduce air resistance and noises by installing air dams, which are projected and housed, to walls before and behind a sound arrestor surrounding a pantograph, projecting the air dam on the windward side and housing the air dam on the leeward side. CONSTITUTION:A sound-insulating wall 2 is mounted around a pantograph 3 set up onto the roof of a car body 1. A windward-side air dam 7 and a leeward-side air dam 8 are installed to front and rear walls 4 and 5 on the windward side and leeward side of the sound-insulating wall 2 in a projecting and receivable manner. The figure shows the case when the car body 1 is moved forward in the direction of the arrow A, and the windward side and the leeward side are reversed when the car body proceeds in the direction opposite to A. Driving means 14a, 14b are driven by an output from a control means 13, the air dam 7 is erected at an angle phi larger than the inclination theta of a front and rear wall 4 on the windward side, and the air dam 8 is received in the front and rear wall 5 on the leeward side. Accordingly, air resistance is lowered effectively, and noises are reduced effectively.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a sound insulation device for a pantograph, and particularly to a sound insulation device for a pantograph suitable for a railway vehicle running at high speed.

[Prior Art] As a conventional sound insulation device for a pantograph of a railway vehicle, for example, as described in Japanese Utility Model Application Publication No. 52-159507, a barrier (pantograph cover) is installed around the pantograph at a height within the vehicle body limit. It is known that sound insulation is achieved by arranging them. This technology is intended to shield the sound generated from the pantograph, but if the barrier is high enough for the height of the pantograph, it is necessary to Due to the separation of airflow that occurs in the flow, there are regions where the average flow velocity is less than the mainstream velocity. When the maximum height position of the pantograph is located within the dome area, a side effect is brought about that the intensity of the sound source of the pantograph aerodynamic platform, which increases or decreases depending on the flow velocity, can be lowered.

[Problems to be Solved by the Invention] The above-mentioned prior art shields the sound generated from the pantograph, and when the barrier has a sufficient height relative to the height of the pantograph, it also shields the noise generated by the pantograph. This has the effect of lowering the intensity of the aerodynamicist's sound source. Here, in order to reduce the intensity of the sound source of the pantograph aerodynamic platform, it is effective to increase the height and inclination angle of the front and rear walls, but if the inclination angle is increased, the aerodynamic platform generated from the barrier becomes excessive, and the overall There were problems of increased sound and increased air resistance.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sound insulation device for a pantograph of a railway vehicle and a sound insulation device for a pantograph of a railway vehicle that can reduce the overall sound of an aerodynamic stand generated from the pantograph and exhibit the effect of lowering air resistance.

[Means for Solving the Problems] In order to achieve the above object, the front and rear walls are supported so that they can be protruded from the surface and retracted, and have an inclination angle larger than the inclination of the front and rear walls in the protruding state. an air tam; a driving means for driving the air dam to cause the air dam to protrude and retract; and a driving means for causing the air dam on the windward side relative to the traveling wind to protrude and the near dam on the leeward side to be retracted depending on the direction of travel of the vehicle. It is equipped with a control means for controlling.

Also, in order to achieve the above object, an air dam supported at the upper ends of the front and rear walls so that the front inclination angle can be adjusted; The vehicle is equipped with a control means for controlling the drive means to adjust the front inclination angle of the air dam at the upper ends of the front and rear walls on the windward side and the front and rear walls on the leeward side of the traveling wind, depending on the traveling direction.

Furthermore, among the above purposes, air dams are provided at the top of the front and rear walls in order to lower the aerodynamic platform generated from the pantograph.

[Function] In the above configuration, the air dam protrudes from the surface of the front and rear walls on the windward side with respect to the traveling wind, or the angle of the air dams at the upper ends of the front and rear walls is adjusted via the drive means by the switching control means according to the traveling direction of the vehicle. In this part, an inclination angle larger than the inclination angle of the existing front and rear walls is formed. Due to the large angle of inclination formed by the air dam, the airflow along the windward front and rear walls and the air dam is diverted upward to the rear, promoting the separation that occurs near the top point and pushing up the backflow area that occurs downstream of it. It weakens the average flow velocity hitting the pantograph and reduces the intensity of the aerodynamic sound source generated from the pantograph. Furthermore, since the direction of the airflow is gradually changed on the roof, front and rear walls, and air dam of the vehicle, the front and rear walls, which have the front slope angle of the air dam after protruding or adjusting the angle, are originally constructed by themselves. It reduces the air resistance of the front and rear walls and reduces the strength of the aerodynamics generated from the front and rear walls.Then, it reduces the overall sound intensity of the aerodynamic platform from the pantograph and the sound insulation cover including the front and rear walls.On the other hand, when running When the air dam is supported so that it can protrude and retract on the front and rear walls on the leeward side with respect to the wind, the air dam will be in the retracted state, and the separation area of the wake of the front and rear walls on the leeward side that occurs when the air dam on the front and rear walls on the leeward side is in the protruding state will be expanded. This reduces the increase in air resistance that occurs depending on the size of the separation area, and reduces the total air resistance with the upper side.

Here, if the air dam is supported at the upper end of the front and rear walls so that its angle can be adjusted, the front slope angle of the air dam at the upper end of the front and rear walls on the leeward side can be adjusted to be smaller than the front slope angle of the existing front and rear walls. The separation area behind the front and rear walls is kept small, and the air resistance that occurs depending on the size of the separation area is reduced.

In addition, by installing air toms with a front inclination angle greater than the 11-plane inclination angle of the existing front and rear walls at the top of the front and rear walls, the air flow along the air toms is transformed upward to the rear, promoting separation and pantograph. This weakens the average flow velocity and reduces the intensity of the pre-aerodynamic sound source generated from the pantograph.

[Example] Hereinafter, an example of the present invention will be described based on FIGS. 1 and 2.

In FIG. 1, a sound insulating cover 2 is provided on the roof of a car body 1 of a railway vehicle to surround a pantograph 3. It is formed from the side wall 6. These front and rear walls 4 and 5 have a windward side air dam 7 and a leeward side air dam 8.
is attached so that it can appear and retract along the guide 9. Here, the air dam has an installation width corresponding to the width of the maximum height portion of the pantograph 3, and has an inclination angle f larger than the inclination angle θ of the front surfaces of the front and rear walls 4 and 5 in the protruding state.

Jacks 10a and lobs are interposed in the air dams 7 and 8 via struts 11a and 1.1b. This jack 10a, 1. Ob is a type that expands and contracts by rotating the shaft, and the lower end of the shaft is connected to the motor 12.
It is connected to the rotating shafts of a and 12b, and is driven and rotated by the motor 12. The motor 12 is wired to a control means 13, and is energized by the control means 13 to rotate. The jacks loa, lob and motors 12a, 12b constitute driving means 14a, 14b, respectively.

As shown in FIG. 2, the control means 13 includes a changeover switch I5, a changeover circuit 16, and a drive circuit I7. Here, the changeover switch 15 causes the changeover circuit 16 to
operates and transfers the control signal from the switching circuit 16 to the drive circuit 1.
7, and the motor 12 is energized based on the signal.

Next, the effect will be explained.

In front of the aerodynamic force generated from the pantograph and pantograph sound insulating cover of a high-speed railway vehicle, as shown in FIG. There is a characteristic that the inverse dependence of the pantograph aerodynamic front (a) and the sound insulation cover aerodynamic front (b) changes accordingly. Here, the size of the pantograph aerodynamic front (a) depends on the size of the separation that occurs at the top point B of the windward side front and back walls 4 shown in the first section, and this mainly depends on the size of the separation that occurs at the front of the front and rear walls at point B. varies depending on the inclination angle. Furthermore, there is a characteristic that the air resistance coefficient co changes as shown in FIG. 4 depending on the inclination angle θ.

In the pantograph sound insulation device according to the embodiment shown in FIGS. 1 and 2, the above aerodynamic characteristics are utilized to control the protrusion and retraction of the air dam 7.8 depending on the direction of travel of the vehicle. That is, the changeover switch 15. switching circuit 16,
Via the drive circuit 17, the windward side air dam 7 protrudes with respect to the traveling wind A, and the leeward side air dam 8 is retracted.
motor], 2a and 12b, and jack loa
performs a projecting operation, and the jack 10b performs a retracting operation.

As mentioned above, in this pantograph sound insulation device, the windward side air dam 7 is controlled to protrude.
As the front inclination angle f of the windward air dam 7 increases, the separation area in the wake of the uppermost position C of the windward air dam 7 increases,
As a result, the average flow velocity between the overhead wire 18 and the maximum height position point of the pantograph 3 is reduced, which has the effect of reducing the strength of the sound source in front of the pantograph aerodynamics, which depends on the flow velocity. In addition, in front of the aerodynamic sound insulation cover, since the air flow along the front inclination angle θ of the existing windward side front and rear walls 4 flows smoothly through the front inclination angle ψ of the windward side air dam 7, the front inclination of the windward side air dam 7 is Compared to the case where the front inclination angle θ of the windward side front and rear walls 4 is configured by the angle ψ, the separation vortex caused by the shape change that occurs at the intersection of the vehicle body l and the windward side front and rear walls 4 can be suppressed to a small value, and the strength of the sound source can be reduced. It has a decreasing effect. Therefore, it is possible to obtain the effect of reducing the pre-aerodynamic total value of the part, which is determined by the decibel sum of both. Moreover, the effect of reducing air resistance can be obtained compared to the case where the front inclination angle θ of the windward side front and rear walls 4 is configured by the front inclination angle T of the windward side air dam 7. Furthermore, the leeward air dam 8
By retracting the air dam 8, as shown in FIG. It is possible to prevent the expansion of the separation area behind the leeward front and rear walls 5 that occurs when the leeward air dam 8 is in the protruding state, and to reduce the increase in air resistance that occurs depending on the size of the separation area.

According to the inventor's experiments, it was possible to obtain the effect of reducing the overall aerodynamic table value as shown in Section 6, and to obtain the drag coefficient C8 as shown in Table 1 below.

Next, a second embodiment of the present invention will be described with reference to FIG. In the figure, the same reference numerals as in the above embodiment indicate the same members. The difference between this embodiment and the first embodiment is that in the non-operating state, the front surfaces 21a and 21. b to front and rear walls 4
and 5, and supports hinges 20a and 20b as axes so that the angles of the front surfaces 21a and 21b of the air dam can be adjusted in the operating state, and are composed of fluid pressure actuated devices 19a and 19b. This means that it can be driven by the device 14. According to such a configuration, in addition to the effects of the first embodiment, the occurrence of a separation region generated in the wake of the leeward side front and rear walls 5 can be suppressed to a small size, and the air resistance can be further reduced.

Next, a third embodiment of the present invention will be described with reference to FIG. In the figure, the same reference numerals as in the above embodiment indicate the same members. The difference in this embodiment is that the air dams 7 and 8 are fixed, which is effective when the purpose is to reduce the pantograph aerodynamic platform, and the existing sound insulation cup (-2) can be easily modified. It is excellent.

[Effects of the Invention] As explained above, according to the present invention, since the air dam can locally increase the separation of airflow, the total aerodynamic force of the pantograph and pantograph sound insulating covers can be reduced, Moreover, it has the effect of reducing the resistance coefficient.

[Brief explanation of the drawing]

FIG. 1 is a side view of a pantograph portion according to an embodiment of the present invention, FIG. 2 is a configuration diagram of the control means of the embodiment of FIG. 1, and FIG. Figure 4 is a diagram of the relationship between the front inclination angle of the front and rear walls and the drag coefficient, Figure 5 is a streamline diagram, and Figure 6 is a diagram of the relationship between aerodynamic noise and the aerodynamics of the sound insulation cover. Experimental results diagram showing the reduction effect, No. 7
The figure is a side view of the pantograph portion of the second embodiment of the present invention, and FIG. 8 is a perspective view of the B pantograph portion of the third embodiment of the present invention. 1------1 vehicle body, 4------1 windward side front and rear walls, 5
------One windward side front and rear wall, 7---One windward side air dam, 8 One leeward side air dam, 14-- O (No. 1 Prisoner i #r Brushing wall tj 1st side of the bondage inward θ (skin) Fig. j Ichimon hawk θ (friend) facing n of the wall O

Claims (1)

[Scope of Claims] 1. A sound insulation device for a pantograph that is provided around a pantograph and shields the sound generated from the pantograph, which is supported so as to be able to protrude and retract from the front inclined surface of the front and rear walls, and which protrudes from the pantograph. an air dam having an inclination angle larger than the inclination angle of the front and rear walls in the state; a driving means for driving the air dam to cause the air dam to protrude and retract; 1. A sound insulation device for a pantograph, comprising: a control means for controlling the driving means so that the windward side air dam is projected and the leeward side air dam is in a retracted state. 2. In a pantograph sound insulation device that is installed around a pantograph and shields the sound generated from the pantograph, an air dam that also serves as the front and rear walls at the upper ends of the front and rear walls and is supported so that the front inclination angle can be adjusted; The front inclination angle of the air dam at the upper end of the front and rear walls on the windward side increases with respect to the traveling wind according to the direction of travel of the vehicle, and the front inclination of the air dam at the upper end of the front and rear walls on the leeward side increases. 1. A sound insulation device for a pantograph, comprising: control means for controlling the drive means so that the angle is reduced. 3. A sound insulation device for a pantograph, which is provided around the pantograph and shields the sound generated from the pantograph, characterized in that an air dam is attached to the upper part of the front and rear walls.