JP3630419B1 - Windshield cover device for current collector in vehicle - Google Patents

Abstract

To further prevent noise and to reduce the weight in some cases.
SOLUTION: A slope 12 portion that gently rises toward the current collector 1 before and after the current collector 1 supported on the roof 4 of the vehicle 3 in the vehicle traveling direction, and whose final portion is a substantially horizontal top portion 12a; In the windshield cover device of the current collector for a vehicle that has at least a cavity portion 13 that leaves an installation area of the current collector 1 between the slope portions 12 and reduces noise during vehicle travel, The above-mentioned object is achieved by setting the distance between the front and rear walls 13a, 13a viewed in the direction to a minimum or a length close to that which satisfies at least the necessary insulation distance between the front and rear slope portions 12 of the current collector 1. To do.
[Selection] Figure 1

Description

  The present invention relates to a windshield cover device for a current collector in a vehicle, and in particular, a windshield cover for a current collector in a vehicle suitable for reducing noise generated from a current collector for a high-speed railway vehicle such as a Shinkansen vehicle, a so-called pantograph. It relates to the device.

  2. Description of the Related Art Conventionally, a windshield cover that surrounds a current collector has been provided in order to reduce the noise by regulating the airflow that hits the current collector on the roof of the vehicle (see, for example, Patent Documents 1 and 2).

  In Patent Literature 1, a slope portion where the final portion rises gently toward the current collector before and after the current traveling direction of the current collector in the vehicle traveling direction, and an installation area of the current collector between these slope portions is provided. There is described a windshield cover device for a current collector that has a remaining cavity portion and reduces noise during vehicle travel. In particular, as an improved invention for a windshield cover described as a conventional one having a rectangular cross section, almost the entire outer surface of the windshield cover is a continuous curved surface and is cut in a direction perpendicular to the vehicle traveling direction. It discloses that the area continuously increases from the rising start edge of the slope toward the hull position, and the change graph of the cross-sectional area along the vehicle traveling direction includes about one third of the straight line region. According to this improved invention, the pressure fluctuation caused by the windshield cover during vehicle travel can be mitigated as compared with the conventional one, and the aerodynamic noise reduction effect is not impaired. Therefore, it contributes greatly to the realization of high-speed travel of railway vehicles exceeding 300 km. Is going to fulfill. At the same time, the projected area is not reduced as compared with the conventional case even though the rate of change in the cross-sectional area can be reduced, so that it is possible to secure a concave region necessary for installing the current collector.

Patent Document 2 discloses a conventional windshield cover of the type described in Patent Document 1 that reduces cavity noise caused by negative pressure and airflow turbulence generated in a concave portion that forms a current collector installation area, a so-called cavity portion. An improved invention is disclosed. This occurs by providing soundproof walls on both sides of the cavity part while suppressing the generation of the cavity sound by the ventilation function while restricting the action of the opposing air flow to the current collector with the slope part as a mesh structure It is possible to reduce the leakage of the cavity sound into the surrounding area.
JP-A-10-126903 JP 2003-219505 A

By the way, some applicants of the present application, like the improved invention disclosed in Patent Document 1, are difficult to manufacture and expensive if the entire outer surface of the windshield cover is a curved surface. It affects other vehicles that pass through the different winds, and the airflow that pushes up toward the hull is uneven and unstable in the width direction of the vehicle, that is, in the direction of the sleepers and in the direction of the sleepers. In order to solve this problem, including the improvement of the windshield cover device b adapted to the single-arm type current collector a as shown in FIGS. Further development is underway to respond to the fact that the running speed is going to exceed 300 km.

As a result of repeated studies with various experiments in such development, the present inventors have greatly affected noise prevention and weight reduction for further speedup, and the windshield cover volume, in the vehicle traveling direction We found that reducing the projected area is an important factor. However, the improved inventions disclosed in Patent Documents 1 and 2 have not been improved from such a viewpoint. Further, the improvement by the previous applicant of the present application has not been sufficiently achieved.

  An object of the present invention is to provide a windshield cover device for a current collector in a vehicle that can further prevent noise and can be reduced in weight in some cases.

In order to achieve the above-described problems, a windshield cover device for a current collector in a vehicle according to the present invention is gradually moved toward the current collector before and after the current collector is supported on the roof of the vehicle. Current collecting device in a vehicle which has at least a slope portion whose rising end portion is a substantially horizontal top portion and a cavity portion which leaves an installation area of the current collecting device between these slope portions, and reduces noise during vehicle travel In the windshield cover device, the front and rear walls of the cavity portion as viewed in the vehicle traveling direction, at least satisfying the required insulation distance between the front and rear slope portions of the current collector, and at a minimum or a length close to it, approximately The main feature is that it is 2850 mm to 3050 mm .

In such a configuration, the cavity between the front and rear slopes of the windbreak cover is connected to the current collector while following the form that does not show the effect of other winds on the other vehicles due to the scraping wind and the drop in lift characteristics due to the push-up wind toward the hull. Although it becomes an installation area, there is no dead space for the necessary insulation distance between the front and rear walls seen in the vehicle traveling direction with respect to the current collector, which has not been considered conventionally, or it is reduced to approximately 2850 mm to 3050 mm since, shrinking Boryuumu occupy correspondingly cavity portion windshield cover and the generation of cavity noise reduction when the air flow directed from the slope of the front side of the vehicle traveling direction to the slope of the rear side exceeds cavity The

  In addition, if there is a wall or the like that corresponds to the length between the front and rear walls of the cavity portion, the length of the wall is shortened to reduce the weight accordingly.

The current collector includes a base supported by a lever on the roof of the vehicle, and a current collecting arm that extends obliquely upward from one side of the vehicle traveling direction of the base to the other side and supports the boat body, The base is supported by an insulator before and after the traveling direction of the vehicle, and the cavity portion has side walls following the front and rear slope portions, and at least a necessary insulation distance between the side walls and the current collector is satisfied. In a further configuration, with a minimum or near length , approximately 1340 mm ,
Even between the side walls of the cavity portion, the dead space for the necessary insulation distance from the current collector, which has not been considered in the past, is eliminated or reduced to approximately 1340 mm, so that the volume occupied by the cavity portion in the windshield cover accordingly. Reduces the generation of cavity noise when the air flow from the front slope part to the rear slope part in the vehicle traveling direction crosses the cavity part, further preventing noise and further speeding up the vehicle Can contribute. At the same time, the width of the front and rear slope parts can be narrowed to the side wall position of the cavity part, so the volume of the windshield cover is reduced and the weight is reduced, the projected area in the vehicle traveling direction is reduced, and the pressure fluctuation range due to air displacement There Ru is suppressed generation of noise due to pressure fluctuations to shrink.

The top portion has a height that is at least approximately equal to the height of the insulator portion that supports the base of the current collector, and the slope portion has cut off the rising start end portion at a set angle from the roof of the vehicle toward the top portion. In a further configuration, having a step, the height of the step is approximately 40 mm to 90 mm ,
The top of the front and rear slopes has almost reached the height of the insulator that supports the base of the current collector, preventing the counter airflow from acting on the insulator where the aerodynamic resistance is particularly large and preventing aerodynamic noise. After satisfying the minimum necessary windshield cover height, the angle of the vehicle is set to the necessary angle to suppress the generation of aerodynamic sound and lift change due to the opposing airflow to the part of the current collector that goes over the windshield cover. By cutting off the rising start edge of the slope portion that rises from the roof, the required length of the slope portion rises, and the volume of the entire windshield cover can be reduced and lightened accordingly. In addition, by suppressing the stepped portion formed by excising the rising start edge of the slope portion to a height of approximately 40 mm to 90 mm , the developmental airflow by pushing up the opposing airflow at the stepped portion is directed to the portion where the current collector is exposed on the windshield cover since it is possible to avoid the influence, things like become a new cause of the occurrence and lift variation of noise is not the name.

In the further configuration in which the length of the vehicle in the traveling direction of the top part is longer than that of the downstream slope part, the thing of the upstream slope part seen in the direction of the anti-flutter side airflow against the current collector is,
The part of the current collector that comes out on the windshield cover has a fluttering side with low aerodynamic resistance and an anti-fluttering side with high aerodynamic resistance against the opposing airflow that is opposite to the traveling direction of the vehicle on the hull support structure. By making the top of the upstream slope portion longer than that of the downstream slope as seen in the direction of the airflow on the anti-swing side, the top of the slope portion on the downstream side is not prone to become longer. Sufficient rectification is obtained by the long top of the slope that works prior to the current collector with respect to the side airflow, and noise prevention and lift fluctuations are suppressed to the same extent as when the fluttering side airflow works. Specifically, the length in the traveling direction of the vehicle at the top of the upstream slope portion of the anti-flutter side airflow is preferably about 250 mm to 1500 mm .

  However, the length of the top slope portion of the upstream slope portion viewed in the direction of the airflow on the side of the fluttering side in the traveling direction of the vehicle is greater than that deviating from the predetermined vicinity region for those in the predetermined vicinity region from the vehicle head portion. Lengthen.

  This is because the degree of development of the boundary layer is still low in the predetermined area from the top of the vehicle, and the flow velocity of the opposing airflow is not sufficiently lowered, so that the top dimension following the slope part is made longer than that outside the predetermined area. This is effective by reducing the flow velocity.

The current collector comprises a base supported by a lever on the roof of the vehicle, and a current collecting arm that extends obliquely upward from one side of the base in the vehicle traveling direction to the other side and supports the hull, The base is flat and has a strip shape that is long in the vehicle traveling direction in plan view.
Since the projected area in the vehicle traveling direction of the base is small and the shape of the aerodynamic resistance against the opposed airflow is small, including a current collecting arm that only extends obliquely upward from the base to one side of the vehicle traveling direction, The height of the windshield cover can be lowered to the extent that it comes out on the windshield cover, and the projected area and volume in the vehicle traveling direction can be further reduced. In addition, the current collecting arm can be accommodated in the range from one side of the base to the other side so as to support the hull, and the cavity should only satisfy the required insulation distance from the base in plan view. Well, it is suitable for keeping the necessary volume of the cavity part small.

The side wall of the cavity part is biased toward one side of the vehicle in the traveling direction, and has a notch for insulation against the stored boat body in the current collector , and the soundproof walls provided on both sides of the cavity part are provided in the cavity part. In the further configuration, which is shorter than the cavity part on the opposite side of the notch before and after the vehicle running direction,
In contrast to the fact that the sound source in the cavity is biased toward the notch and not on the opposite side of the notch, the soundproof walls provided on both sides of the cavity are shorter than the cavity on the opposite side of the notch. By doing so, the soundproof wall can be shortened and the volume can be made smaller and lighter without increasing the generation of noise around.

In a further configuration, the angle of rise of the sound barrier before and after the running direction of the vehicle is approximately 30 ° .
Without increasing the length of the base of the soundproof wall, the aerodynamic resistance against the opposing airflow of the soundproof wall is reduced, and the generation of aerodynamic sound is suppressed by that amount, and the airflow pushed up by the slope and cavity is less likely to be disturbed. There is an advantage that the lift characteristics are not deteriorated.

In a further configuration, the length of the soundproof wall in the traveling direction of the base vehicle is approximately 4850 mm, whereas the length between the front and rear walls of the cavity portion is approximately 2850 mm .
While preventing the influence around the cavity sound, the length is reduced, the volume is reduced, and the weight is further reduced.

  Further objects and features of the present invention will become apparent from the following detailed description and drawings. Each feature of the present invention can be used alone or in combination in various combinations as much as possible.

According to the windshield cover device of the current collector in the vehicle of the present invention, the volume of the cavity portion is maximized while following the form in which the effect of other winds on the other vehicles and the decrease in the lift characteristics due to the push-up wind toward the hull are observed. Since the insulation distance from the current collector is reduced to approximately 2850 mm to 3050 mm, the generation of cavity noise is reduced, which is effective in further increasing the speed of the vehicle. In addition, since the length of the wall and the like required corresponding to the cavity portion is shortened to reduce the weight, this aspect can also contribute to further speedup of the vehicle. In addition, shortening the length of the side wall of the cavity portion reduces the left-right aerodynamic force and does not promote left-right vibration, leading to improved riding comfort.

The current collector includes a base supported by a lever on the roof of the vehicle, and a current collecting arm that extends obliquely upward from one side of the vehicle traveling direction of the base to the other side and supports the boat body, The base is supported by insulators in the front and rear directions of the vehicle, and the cavity portion has side walls that follow the front and rear slope portions, and a necessary insulation distance is provided between the side walls and the front and rear slope portions of the current collector. According to a further configuration, which is at least satisfactory, with a minimum or near length of approximately 1340 mm ,
Since the volume of the cavity portion is reduced to approximately 1340 mm even between the side walls thereof, the generation of cavity sound is reduced, which can contribute to further speeding up of the vehicle. At the same time, the volume of the windshield cover, including the front and rear slopes, is reduced and the weight is reduced, and the projected area in the direction of travel of the vehicle is reduced and the generation of noise due to pressure fluctuations can be suppressed, further increasing the speed of the vehicle. It is valid.

The top portion has a height that is at least approximately equal to the height of the insulator portion that supports the base of the current collector, and the slope portion has cut off the rising start end portion at a set angle from the roof of the vehicle toward the top portion. According to a further configuration having a step, the height of the step is approximately 40 mm to 90 mm ,
At the height of the windshield cover that prevents the generation of aerodynamic noise at the insulator where the aerodynamic resistance is particularly large, at an angle set to suppress the generation of aerodynamic noise and the change in lift at the portion of the current collector that protrudes above the windshield cover The volume of the windshield cover is reduced and lightened by shortening from the required rising length by cutting off the rising start edge of the slope part, and the stepped part by cutting the rising start edge is approximately 40 mm to 90 mm in height. Since it is possible to avoid disturbing the opposing airflow and affecting the portion of the current collector that is on the windshield cover, it is effective for further speeding up of the vehicle.

According to a further configuration, the length in the running direction of the vehicle at the top is longer on the anti-flutter side than on the flutter side against the opposing airflow of the current collector.
Since the top of the fluttering side is not lengthened, noise prevention and lift fluctuation due to the opposite airflow on the fluttering side can be suppressed to the same extent as the fluttering side, which is effective for further speeding up of the vehicle.

However, the length of the top slope portion of the upstream slope portion viewed in the direction of the airflow on the side of the fluttering side in the traveling direction of the vehicle is greater than that deviating from the predetermined vicinity region for those in the predetermined vicinity region from the vehicle head portion. By increasing the length, it is possible to cope with the fact that the degree of development of the boundary layer is still low within the predetermined area from the front of the vehicle, and the flow velocity of the opposing airflow is not sufficiently reduced.

The current collector comprises a base supported by a lever on the roof of the vehicle, and a current collecting arm that extends obliquely upward from one side of the base in the vehicle traveling direction to the other side and supports the hull, According to a further configuration, the base is flat and has a long strip shape in the vehicle traveling direction in plan view.
The windshield cover can be lowered to the extent that the base comes out, and the projected area and volume in the vehicle traveling direction can be further reduced. Further, since the cavity portion satisfies the necessary insulation distance from the base in a plan view without being affected by the current collecting arm and the necessary volume of the cavity portion can be kept small, it is effective for further speeding up of the vehicle.

The side wall of the cavity portion is biased toward one side of the vehicle in the traveling direction and has a notch for insulation against the stored boat body, and the soundproof walls provided on both sides of the cavity portion are provided with the notched vehicle of the cavity portion. According to the further configuration, which is shorter than the cavity part, on the opposite side in the running direction,
The sound barriers on both sides corresponding to the bias of the sound source from the cavity part are shorter than the cavity part on the opposite side of the notch, making the volume smaller and lighter without increasing the noise generation around, so the vehicle It is effective for further speedup.

According to a further configuration, the rising angle of the sound barrier before and after the running direction of the vehicle is approximately 30 ° .
Since the base length is not lengthened, the aerodynamic resistance of the sound barrier is reduced and the generation of aerodynamic noise is suppressed, and the lift characteristics are not deteriorated without affecting the lifted airflow at the slope and cavity. It is effective for further speeding up.

According to a further configuration, the length of the soundproof wall in the traveling direction of the vehicle at the base is approximately 4850 mm, whereas the length between the front and rear walls of the cavity is approximately 2850 mm .
While preventing the influence of the sound around the cavity, further weight reduction is effective for further speeding up of the vehicle.

Per the preferred embodiment of according to the windshield cover device of the current collector in a vehicle of the present invention, it will be described in detail with reference to FIGS. 1-17. This embodiment is an example in the case of the windshield cover apparatus 10 improved corresponding to the current collector 1 for a railway vehicle as shown in FIGS. The current collector 1 is a further improvement of the current collector a targeted by the windshield cover device b shown in FIGS. 18 to 20 described above, and is supported on the roof 4 of the vehicle 3 by insulators 5, 5, 6. And a current collecting arm 9 that extends obliquely upward from one side to the other side in the vehicle traveling direction of the base 7 and supports the boat body 8, and the base 7 is flat vertically. In the plan view, it has a long strip shape in the vehicle running direction. However, it has a substantially streamlined outer shape that is rounded as a whole, is well-familiar with the opposing airflow, and does not easily peel off. The insulators 5, 5 and the insulator 6 share and support the front and rear in the vehicle traveling direction of the base 7, and the insulator 6 is positioned on the rising side of the current collecting arm 9 from the base 7 and the distribution cable 11. Also used as a cable head. However, the present invention is not limited to this, and is effective when applied to the current collector shown in FIGS. 18 to 20 and others, and belongs to the category of the present invention.

In the case of a single arm type current collector or the like that is not targeted before and after the vehicle traveling direction, the portion of the current collector 1 that protrudes on the windshield cover 10 is opposite to the vehicle traveling direction on the support structure of the boat body 8. 1 has a fluttering side with a low aerodynamic resistance and an anti-fluttering side with a high aerodynamic resistance. In the case shown in FIGS. On the side. This is referred to as a fluttering side airflow for convenience. The counter airflow 21a facing in the opposite direction is referred to as the anti-flutter side airflow for convenience. This does not refer to the traveling direction of the vehicle 3 but to the opposing airflow received by each of the current collector 1 and the windshield cover device 10 installed in the vehicle 3 in the traveling direction of the vehicle 3.

  The windshield cover device 10 rises gently toward the current collector 1 before and after the current collector 1 supported on the roof 4 of the vehicle 3 in the vehicle traveling direction, and the slope portion 12 whose final portion is a substantially horizontal top portion 12a. The windshield cover 10 having at least the cavity portion 13 that leaves the installation area of the current collector 1 between the slope portions 12 reduces noise during vehicle travel. In particular, the length between the front and rear walls of the cavity portion 13 as viewed in the vehicle traveling direction, that is, the cavity portion length B satisfies at least the necessary insulation distance between the front and rear slope portions 12 and 12 of the current collector 1. The length should be at or near the minimum.

  As a result, while following the form that does not show the influence on the other vehicles due to the scraping wind and the lift characteristic degradation due to the push-up wind toward the hull 8, the wind collecting cover 10 gathers in the cavity portion 13 between the front and rear slope portions 12, 12. When the electric device 1 is installed, there is no dead space between the front and rear walls 13a and 13a viewed in the vehicle traveling direction with respect to the necessary insulation distance with the current collector 1 that has not been considered in the past, or the electric device 1 is reduced. . Therefore, the volume occupied by the cavity 13 in the windshield cover 10 is reduced by the amount of the dead space disappearing or being reduced. The reduction of the volume of the cavity 13 is caused by the sound of the cavity generated when the opposing air flow 21 as shown in FIG. 5 from the slope 12 on the front side in the vehicle traveling direction toward the slope 12 on the rear side exceeds the cavity 13. Occurrence is reduced.

FIG. 5 is based on a numerical fluid simulation. (A) is a case where the cavity part length B of this embodiment is 2850 mm, (b) is a case where the cavity part length B further extended by 600 mm is 3450 mm, and (c) is a comparative example. As shown in FIG. 18 to FIG. 20 , the cavity part length B is 3960 mm. From these experimental results, it can be seen that as the cavity length B increases, the counter airflow 21 becomes more turbulent, and in particular, the angle of entry into the cavity 13 is larger. I understand that

  This is the case of FIGS. 5A and 5B and the case where the cavity portion length B is 3300 mm by extending 450 mm between them, and the flow angle at the angular flow position of the counter airflow 21 is the width of the roof 4. When viewed from the center position in the direction, the height level of the top 12a of the windshield cover 10 and the height level of the hull 8 are as shown in FIGS. 6 (a) and 6 (b). At the top 12a level, as shown in FIG. 6 (a), as the cavity length B increases, the flow angle at the rear wall 13a increases toward the + side. I understand. At the ship body 8 level, the influence of the size of the cavity length B is hardly seen.

FIG. 7 shows the noise measured by the microphones 1 to 4 at the respective positions shown in FIG. 7 in the wind tunnel experiment in the case where the cavity length is 2850 mm and the case where the cavity length is 200 mm longer than that in the present embodiment. FIG. 8 shows the microphone 2 directly above the boat body 8, and it can be seen that the noise can be suppressed to the same level even when the cavity length is extended by 200 mm from the dimension 2850 mm of the present embodiment. Cavity length B from the noise limit is effective, including the case of the comparative example is suppressed almost 2850Mm～3450mm, the most preferable to reduce to approximately 3050 mm.

  Here, since the current collector 1 of the present embodiment has a small projected area in the vehicle traveling direction of the base 7 and has a shape with a small aerodynamic resistance against the counter airflow 21, the vehicle travels from the base 7. Including the current collecting arm 9 that only extends obliquely upward on one side of the direction, the height of the windshield cover 10 is lowered to the extent that it protrudes above the windshield cover 10 to further reduce the projected area and volume in the vehicle traveling direction. Can be achieved. Further, the current collecting arm 9 can be substantially accommodated in the range from one side to the other side of the base 7 as shown in FIG. 2 to support the boat body 8, and the cavity portion 13 prevents the arrangement of current collecting devices. However, it is sufficient to satisfy only the necessary insulation distance from the base 7 in plan view, which is suitable for keeping the necessary volume of the cavity portion 13 small and effective for further speeding up of the vehicle.

  The base 7 has a small projected area in the vehicle traveling direction and a small aerodynamic resistance with respect to the opposing airflow 21 including the current collecting arm 9. A sufficient supporting strength can be obtained only by being supported by. Further, since the insulator 6 on one side of the front and rear is also used as a cable head, the current collecting device in the cavity portion 13 is almost within the range of the base 7 in plan view. Therefore, the necessary insulation distance between the cavity portion 13 and the current collector 1 and the dead space seen from the necessary insulation distance can be reduced, and the necessary volume of the cavity portion 13 can be kept small, which is effective for further speedup of the vehicle. is there.

  This is shown in FIG. 9 in the noise measurement by wind tunnel experiments in each case of the current collector 1 fully equipped, no hull, no hull, no current collecting arm, and no current collecting device. As is apparent from the figure, it was verified that the presence or absence of the boat body 8 has a great influence on the generation of noise, whereas the presence of the current collecting arm 9 and the base 7 has almost no influence.

  If there are side walls 13b and sound insulation walls 22 on both sides of the cavity portion 13 that correspond to the cavity portion length B between the front and rear walls 13a, 13a of the cavity portion 13, the lengths thereof are shortened accordingly. Reduce weight. Therefore, this aspect can also contribute to further speeding up of the vehicle.

Further, in the present embodiment, the cavity portion 13 has a minimum length or a length close to it that satisfies at least a necessary insulation distance between the side walls 13b and 13b following the front and rear slope portions 12 and the current collector 1. It is as. Thereby, even between the side walls 13b and 13b of the cavity part 13, the dead space with respect to the required insulation distance with the collector 1 which was not considered conventionally is lost or reduced. Accordingly, the volume occupied by the cavity portion 13 in the windshield cover 10 correspondingly decreases, and the cavity when the counter airflow 21 from the front slope portion 12 toward the rear slope portion 12 in the vehicle traveling direction exceeds the cavity portion 13. The generation of sound is reduced and further noise can be prevented. Therefore, it can contribute to further speeding up of the vehicle. At the same time, since the width W of the front and rear slope portions 12 and 12 can be reduced to the position of the side walls 13b and 13b of the cavity portion 13, the volume of the windshield cover 10 as a whole is reduced and the weight is reduced. In addition, the projected area in the vehicle traveling direction is reduced, the pressure fluctuation region due to the displacement of air is reduced, and the generation of noise due to the pressure fluctuation can be suppressed. In the present embodiment, the length w between the side walls 13b is suppressed to approximately 1340 mm, and the width W of the windshield cover 10 is suppressed to approximately 1380 mm .

Incidentally, the current collector 1 and the required insulation distance between the cavity portion 13 is substantially 300mm or more, preferably electrical safety can be achieved as approximately 320 m m or more above. In this embodiment, the insulation distance of about 320 mm is sufficiently satisfied.

In the present embodiment, the top portion 12a of the slope portion 12 has a height H substantially equal to at least the height of the insulators 5, 5, and 6 that support the base 7 of the current collector 1, and the slope portion 12
It is assumed that a step 12c is formed by cutting off a rising start end at a set angle θ from the roof 4 to the top 12a. As a result, the top portions 12a of the front and rear slope portions 12 almost reach the height of the insulators 5, 5 and 6 supporting the base 7 of the current collector 1, so that the aerodynamic resistance is particularly large. The portion where the slope portion 12 protrudes above the windshield cover 10 of the current collector 1 after satisfying the minimum cover height W that prevents the counter airflow 21 from acting on the portion 6 and generating aerodynamic sound. By cutting off the rising start from the roof 4 at an angle θ set to suppress the generation of aerodynamic sound and lift change due to the opposed airflow 21, the required rising length of the slope portion 12 is shortened, and the windshield cover accordingly The total volume of 10 can be reduced and reduced in weight. In addition, the stepped portion 12c formed by cutting off the rising start end of the slope portion 12 is suppressed to a predetermined height h or less, so that the developed airflow caused by the pushing up of the opposed airflow 21 of the stepped portion 12c is generated on the windshield cover 10 of the current collector 1. Therefore, it is possible to avoid the influence on the part of the ship 8, particularly the hull 8, so that there is no new cause of noise or lift fluctuation.

FIGS. 10A and 10B show the flow of the counter airflow 21 by the numerical fluid simulation when the height h of the stepped portion 12c is 90 mm and 40 mm. The length of the windshield cover 10 can be shortened by cutting up to approximately 90 mm, and if it is less than 40 mm, the shortening effect is reduced. Therefore, the height h of the stepped portion 12c is preferably set to approximately 40Mm～90mm. 11 and 12 show the difference in flow velocity vector between the case where the height h of the stepped portion 12c is 90 mm and that in the case where the height h is 40 mm, the flow velocity vectors are not significantly different from each other.

In addition, about the flow angle of the opposing airflow 21 with respect to the rising angle θ of the slope portion 12, a numerical fluid simulation was performed at the top 12a level and the boat body 8 level, and the results were as shown in FIGS. 13 (a) and 13 (b). In either case, the smaller the angle θ, the smaller the flow angle, the smaller the change in angle proportional to the pressure gradient, and it has been found that it approaches 0 ° at the level of the hull 8 and is approximately 9.5 ° to 17 °. It was found that aerodynamic noise and cavity noise can be sufficiently prevented if there is. However, since the required rising length of the slope portion 12 becomes longer as the rising angle θ is smaller, it is preferable to set θ = 14 ° in view of the shortening effect by the step portion 12c.

  FIG. 14 shows the difference in noise by the wind tunnel experiment between the case where the height h of the stepped portion 12c is 90 mm and the case where it is 30 mm, but it can be seen that there is not much difference between the two.

  With respect to the length L of the horizontal portion of the vehicle traveling direction by the top portion 12a, the opposite airflow 21 is viewed at the level of the hull 8 with the flow velocity and the flow angle of the opposite airflow 21 as shown in FIGS. Correlation was obtained from numerical fluid simulation. According to this, it can be seen that the longer the length L of the top portion 12a, the smaller the flow velocity and the flow angle of the opposing airflow 21 acting on the hull 8 and the better the performance of preventing aerodynamic noise and lift fluctuation. However, the length L of the top portion 12a directly affects the length of the windshield cover 10 and causes an increase in volume and weight.

Therefore, regarding the length of the top portion 12a in the traveling direction of the vehicle 3, the length l of the upstream slope portion 12 portion viewed in the direction of the anti-fluttering side airflow 21a shown in FIGS. Is longer than the length L of the slope portion 12 on the downstream side. In this way, by making the length l of the top portion 12 of the upstream slope portion 12 viewed in the direction of the anti-fluttering-side airflow 21a longer than the length L of the downstream portion, the downstream slope portion 12 Without causing the top 12a to become longer, the anti-fluttering-side airflow 21a can be prevented from noise by obtaining a longer rectifying action by the long top 12a of the slope portion 12 that works prior to the current collector 1. The lift fluctuation can be suppressed to the same extent as when the fluttering side airflow 21 works. Therefore, generation of aerodynamic sound and lift fluctuation can be further suppressed without increasing the weight, which is effective for further speeding up of the vehicle. Specifically, FIG.
6 (a) and 6 (b), the vehicle running direction of the top portion 12a of the upstream slope portion 12 as seen on the anti-flutter side from the wind tunnel test results of the flow velocity and the flow angle at the boat body 8 level of the opposed airflow 21. The length l is preferably approximately 250 mm to 2000 mm .

  However, the length L before and after the vehicle traveling direction of the top portion 12a of the upstream slope portion 12 as viewed in the direction of the fluttering-side airflow 21 is within a predetermined vicinity region from the vehicle head portion. Make it longer than what comes off. This is because the degree of development of the boundary layer is still low within a predetermined area from the front of the vehicle, and the flow velocity of the counter airflow 21 is not yet sufficiently reduced. This is effective by reducing the flow velocity by making the dimension longer than that outside the predetermined range.

1 to 3, the side wall 13b of the cavity portion 13 has a notch 31 that is biased toward one side of the vehicle 3 in the front and rear direction of the vehicle 3 so as to insulate the stored boat body 8, and The soundproof walls 22 provided on both sides of the part 13 are shorter than the cavity part 13 on the opposite side of the notch 31 of the cavity part 13 in the vehicle traveling direction. Accordingly, in response to the deviation of the sound source from the cavity 13 determined by the wind tunnel experiment, the soundproof walls 22 on both sides are made shorter than the cavity 13 on the opposite side of the notch 31 as shown in FIGS. Thus, the volume is reduced by reducing the volume without increasing the noise generation around the vehicle, which is effective for further speeding up of the vehicle. Specifically, in the example shown in FIG. 2, the reduction is 2850 mm− (1475 mm + 145 mm) = 1230 mm.

Overall, in the noise measurement by the overall wind tunnel experiment in the comparative example shown in FIGS. 18 to 20 and the case of the present embodiment, the fluttering side in FIG. 17A and the noise measurement in FIG. As shown in the results on the anti-flutter side, it is verified that the noise of the present embodiment is reduced on both sides as compared with the comparative example, and the weight is reduced.

The rise of the soundproof wall before and after the running direction of the vehicle should be inclined to the downstream side with respect to the opposing airflow 21, and by making the inclination approximately 30 ° , the base length is not lengthened easily. The aerodynamic resistance with respect to the counter airflow 21 is reduced, but the generation of aerodynamic sound is reduced accordingly, and the lifted airflow by the slope portion and the cavity portion is hardly disturbed, and there is an advantage that the lift characteristics are not deteriorated.

The sound barrier, the length of the running direction of the base portion of the vehicle, against almost 2850M m length of the front and rear walls of the cavity, by substantially 4850M m, while preventing the influence on the surrounding cavity sounds, The length is small, the volume is small, and the weight is further reduced.

  Further, when both shoulders of the slope portion 12 are rounded, the conditions of aerodynamic resistance and lift characteristics with respect to the opposing airflow 21 are good. The radius of curvature R of the round shape may exceed 40 mm, and at 150 mm, it is about 0.3 dB lower than that of 40 mm.

  Of course, it can be industrially used as a windproof cover for a current collector in a Shinkansen vehicle, and it can contribute to further speedup.

It is a perspective view which shows the windshield cover apparatus of the current collector for rail vehicles which concerns on embodiment of this invention. It is a side view of the windshield cover apparatus of FIG. It is a top view of the windshield cover apparatus of FIG. It is a front view of the windshield cover apparatus of FIG. It is a side view which shows the relationship between the size of the size between the front and rear walls of the cavity part in the windshield cover apparatus of FIG. It is a graph which shows the relationship of the flow angle of the opposing airflow in the top part of a slope part and the ship body part by the difference in the size of the cavity in the windshield cover apparatus of FIG. It is explanatory drawing which shows the installation position of the microphone when the noise measurement in the wind tunnel experiment in the windshield cover apparatus of FIG. 1 is performed. It is a graph which shows the noise measurement result of the windproof cover apparatus of FIG. 1 by the installation microphone of FIG. 7, and what extended the cavity 200 mm. It is a graph which shows the noise measurement result in each case with the whole current collector of the windshield cover apparatus of FIG. 1, a boat body, no current collector arm, no boat body, and no current collector. It is explanatory drawing which shows the relationship with the flow of the opposing airflow by the difference in the height of the level | step-difference part which can be obtained by the stand-up base part cutting of the slope part of the windshield cover apparatus of FIG. It is an experiment figure which shows distribution of the flow velocity vector of an opposing air flow in Fig.10 (a). It is an experiment figure which shows distribution of the flow velocity vector of an opposing air flow in FIG.10 (b). It is a graph which shows the relationship of the flow angle of the opposing airflow in the top part of a slope part and the boat body part by the difference in the magnitude | size of the rising angle of the slope part in the windshield cover apparatus of FIG. It is a graph which shows the noise measurement result by the difference in the height of the level | step-difference part formed by the standup base part cutting of the slope part of the windshield cover apparatus of FIG. It is a graph which shows the relationship with the flow velocity of an opposing air flow by the difference in the length of the top part of a slope part, and the relationship with a flow angle and inclination by (a) (b). In the windshield cover device of FIG. 1, the flow velocity of the opposing airflow in the boat body due to the difference in length when the top portion of the upstream slope portion is made longer than that on the downstream side with respect to the anti-fluttering side airflow and Ru graph der showing the relationship between the flow angle at (a) (b). It is a graph which shows the measurement result of a noise with respect to the airflow of the windshield cover apparatus of FIG. It is a side view of the windshield cover apparatus of a comparative example. It is a top view of the windshield cover apparatus of FIG. It is a front view of a windshield cover device of Figure 18.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Current collector 3 Vehicle 4 Roof 5, 6 Insulator 7 Base 8 Ship body 9 Current collecting arm 10 Windshield cover device 12 Slope part 12a Top part 12c Step part 13 Cavity 13a Front and rear wall 13b Side wall 21 Opposite air flow, flutter side counter air flow 21a Anti-flutter side airflow

Claims (10)

The slope of the current collector, which is supported on the roof of the vehicle, slowly rises up and down toward the current collector before and after the vehicle traveling direction, and the current collector is installed between these slopes. A windshield cover device for a current collector in a vehicle that has at least a cavity portion that leaves an area and reduces noise during vehicle travel,
The distance between the front and rear walls of the cavity portion viewed in the vehicle running direction is at least 2850 mm to 3050 mm with a minimum or near length that satisfies at least the necessary insulation distance between the front and rear slope portions of the current collector. A windshield cover device for a current collector. The current collector includes a base supported by a lever on the roof of the vehicle, and a current collecting arm that extends obliquely upward from one side of the vehicle traveling direction of the base to the other side and supports the boat body, The base is supported by insulators before and after the running direction of the vehicle, and the cavity portion has side walls following the front and rear slope portions, and at least a necessary insulation distance between the side walls and the current collector is satisfied. The windshield cover device for a current collector in a vehicle according to claim 1 , wherein the windscreen cover device has a minimum or a length close to 1340 mm . The top portion has a height that is at least approximately equal to the height of the insulator portion that supports the base of the current collector, and the slope portion is cut off at the start end at a set angle from the roof of the vehicle toward the top. The windshield cover device for a current collector in a vehicle according to any one of claims 1 and 2 , comprising a step portion, and the height of the step portion is approximately 40 mm to 90 mm . The length of the top slope portion of the upstream slope portion as viewed in the direction of the airflow on the fluttering side in the traveling direction of the vehicle is longer than that deviating from the predetermined vicinity region for those in the predetermined vicinity region from the vehicle head. Item 4. A windshield cover device for a current collector in a vehicle according to any one of Items 1 to 3 . The length in the running direction before and after the vehicle apex, those upstream slope portion as viewed in the direction of the anti-flutter side facing the air flow with respect to the current collector, according to claim 1 to 4 were longer than that of the slope portion of the downstream A windshield cover device for a current collector in a vehicle according to claim 1. The windshield cover of the current collector in the vehicle according to any one of claims 1 to 5 , wherein a length of the top portion of the upstream slope portion of the anti-swing-side airflow in the traveling direction of the vehicle is approximately 250 mm to 1500 mm. apparatus. The current collector includes a base supported by a lever on the roof of the vehicle, and a current collecting arm that extends obliquely upward from one side of the vehicle traveling direction of the base to the other side and supports the boat body, The windshield cover device for a current collector in a vehicle according to any one of claims 3 to 6, wherein the base is flat and has a strip shape that is long in the vehicle traveling direction in plan view. The side wall of the cavity part is biased toward one side of the vehicle in the traveling direction, and has a notch for insulating the hull stored in the current collector , and the soundproof walls provided on both sides of the cavity part The windshield cover device for a current collector in a vehicle according to claim 7 , wherein the notch is shorter than the cavity portion on the opposite side of the notch in the vehicle traveling direction. 9. The windshield cover device for a current collector in a vehicle according to claim 8 , wherein the inclination angle of the sound barrier before and after the running direction of the vehicle is approximately 30 degrees . The sound barrier, the length of the running direction of the base portion of the vehicle, whereas the length approximately 2850M m around walls of the cavity, to any one of claims 8, 9 is substantially 4850M m A windshield cover device for a current collector in the vehicle described above.

Images