JP7399076B2 - Aerodynamic noise reduction structure of current collector and its manufacturing method - Google Patents

Description

The present invention relates to an aerodynamic noise reduction structure for a current collector that reduces aerodynamic noise generated from the current collector, and a method for manufacturing the same.

(Regarding aerodynamic noise reduction using porous materials)
In order to increase the speed of Shinkansen (registered trademark) trains, reducing aerodynamic noise emitted from each part of the vehicle is an important issue. A pantograph is a major aerodynamic sound source, and of all the parts of a pantograph, the hull and support section make the largest contribution to the aerodynamic sound source. Smoothening the cross-sectional shape and applying through holes are effective ways to reduce aerodynamic noise in the hull, but this alone is not sufficient; it is also necessary to alleviate flow interference between the hull and the boat support. As one method to alleviate the flow interference between the hull and the boat support, we have proposed a method of applying (pasting) a porous material with continuous pores to the surface of the apex cover of the boat support.

A conventional aerodynamic noise reduction structure includes an open-cell porous body on the surface of an object to reduce aerodynamic noise (see, for example, Patent Document 1). Regarding the aerodynamic noise reduction effect by attaching a porous material to the surface and its application to a current collector, a porous material is attached to the surface of a cylindrical specimen to reduce aerodynamic noise (see, for example, Non-Patent Document 1). In order to reduce aerodynamic noise by applying porous material to the boat support part of a pantograph, a method of reducing aerodynamic noise by embedding porous material in the minimum necessary area has been proposed (for example, see Non-Patent Document 2). .

(About the application and installation method of porous materials to existing vehicles)
In the wind tunnel tests, porous urethane resin material, which is easy to process, was used, but when applied to actual vehicles, it is necessary to use porous metal material and firmly attach it to the object. Techniques for attaching porous metal materials include gluing, riveting, or sequential lamination with an FRP matrix. In a conventional installation structure for a porous metal material having a cellular structure, a porous material is fixed to a non-fixed member using a rivet body that passes through a through hole in the porous material and a fixed member (see, for example, Patent Document 2). The conventional mounting structure for cellular porous metal materials is to apply an FRP film-forming material to the surface of the porous material to form a fixing layer, and then fix the fixing layer and the member to be fixed with screws. For example, see Patent Document 3). The conventional method of applying porous metal onto a non-fixed member is to infiltrate a bonding layer resin into the surface of a molded porous metal panel and harden it, and then form an FRP layer on the surface of this bonding layer resin (for example, , see Patent Document 4).

Japanese Patent Application Publication No. 2008-136332

Takeyuki Sueki, and 2 others, "Aerodynamic noise reduction effect by surface attachment of porous material and its application to current collectors", Railway Research Institute report, Kenyusha General Incorporated Foundation, 2008, Vol. 22, No. 5, p.11-16

Tsuyoshi Hikari and 3 others, "Aerodynamic noise reduction by applying porous material to the boat support part of a pantograph", 28th Environmental Engineering Comprehensive Symposium, Japan Society of Mechanical Engineers, July 11-12, 2018 , No.18-10

Japanese Patent Application Publication No. 2009-085406

Japanese Patent Application Publication No. 2009-085407

Japanese Patent Application Publication No. 2010-208287

Conventional cellular structure porous metal material installation structures involve attaching the metal porous material to the surface of the pantograph member with adhesive, etc., and it is difficult to apply to complex three-dimensional curved surfaces due to processing constraints. There are also issues such as the inability to manufacture using high-strength methods such as integral molding.

An object of the present invention is to provide an aerodynamic noise reduction structure for a current collector that can be applied to a member with simple processing, can be attached with high strength, and can be integrally molded using a molding technique, and a method for manufacturing the same.

The present invention solves the above problems by means of solving the problem as described below.
Note that although the description will be given with reference numerals corresponding to the embodiments of the present invention, the present invention is not limited to these embodiments.
The invention of claim 1 is an aerodynamic noise reduction structure for a current collector (3) that reduces aerodynamic noise generated from the current collector (3), as shown in FIGS . 7, 10 to 13, and 15. A plurality of openings (23) for allowing the flow (F) to flow into the inside of the apex cover (8) of the current collector and allowing the flow to flow out from the inside of the apex cover , and connecting the plurality of openings to each other. The plurality of flow passages are arranged at intervals in a plurality of directions (X, Y, Z) inside the vertex cover , and the plurality of flow passages are arranged at intervals in a plurality of directions (X, Y, Z) inside the vertex cover . The flow flowing in from the opening of the high pressure section on the surface flows out from the opening of the low pressure section on the surface of the apex cover , and the top surface and side portions of the aerodynamic sound reduction structure are connected to the top surface (8a) of the apex cover. and the side surface portion (8c), forming a part of this apex cover, and the plurality of openings are formed along the upper edge portion (8e) of the apex cover. This is an aerodynamic noise reduction structure (20A, 20B) for a current collector, characterized in that it is formed on the top and side surfaces of the cover .

According to a second aspect of the present invention, in the aerodynamic noise reduction structure for a current collector according to the first aspect, as shown in FIGS. This aerodynamic noise reduction structure for a current collector is characterized in that the interior extends in three axial directions (X, Y, Z), and flow paths extending in each axial direction intersect at an intersection (25).

The invention according to claim 3 is the aerodynamic noise reduction structure for the current collector according to claim 1 or 2, in which, as shown in FIGS. 10 and 13, the aerodynamic noise reduction structure The apex cover is inserted between the boat support part (7) covered by the apex cover and the aerodynamic sound reduction structure, This aerodynamic noise reduction structure for a current collector is characterized by comprising a fixing part (26) that removably fixes this aerodynamic noise reduction structure to the boat support part together with the apex cover .

The invention of claim 4 is a method for manufacturing an aerodynamic noise reduction structure for a current collector that reduces aerodynamic noise generated from the current collector (3), which This is a method for manufacturing an aerodynamic noise reduction structure for a current collector, characterized in that the aerodynamic noise reduction structure (20A, 20B) for the current collector described above is manufactured using a shaping device.

According to this invention, it can be applied to a member with simple processing, it can be attached with high strength, and it can be integrally molded using a molding technique.

1 is a perspective view schematically showing a part of a current collector including an aerodynamic noise reduction structure of a current collector according to a first embodiment of the present invention; FIG. 1 is a side view schematically showing a current collector including an aerodynamic noise reduction structure of a current collector according to a first embodiment of the present invention. 1 is a plan view schematically showing a current collector including an aerodynamic noise reduction structure for a current collector according to a first embodiment of the present invention; FIG. FIG. 1 is a front view schematically showing a current collector including an aerodynamic noise reduction structure for a current collector according to a first embodiment of the present invention. 1 is a rear view schematically showing a current collector including an aerodynamic noise reduction structure of a current collector according to a first embodiment of the present invention; FIG. FIG. 1 is a schematic diagram schematically showing the structure of a current collector including an aerodynamic noise reduction structure of a current collector according to a first embodiment of the present invention. FIG. 1 is a perspective view schematically showing a vertex cover including an aerodynamic noise reduction structure of a current collector according to a first embodiment of the present invention. FIG. 2 is a plan view schematically showing a vertex cover including an aerodynamic noise reduction structure of a current collector according to a first embodiment of the present invention. FIG. 2 is a side view schematically showing a vertex cover including an aerodynamic noise reduction structure of a current collector according to a first embodiment of the present invention. 9 is a cross-sectional view taken along the line XX in FIG. 8. FIG. 1 is an external view schematically showing an aerodynamic noise reduction structure of a current collector according to a first embodiment of the present invention, in which (A) is a plan view, (B) is a side view, and (C) is a rear view. It is a diagram. FIG. 12 is a cross-sectional view taken along line XII-XII in FIG. 11(B). FIG. 12 is a cross-sectional view taken along line XIII-XIII in FIG. 11(B). It is a photograph for explaining the effect of the aerodynamic noise reduction structure of the current collector according to the first embodiment of the present invention, and (A) is a photograph showing an enlarged view of a porous material simulating the aerodynamic noise reduction structure. , (B) and (C) are contour diagrams of the flow field when the aerodynamic noise reduction structure is provided, and (E) and (F) are contour diagrams of the flow field when the aerodynamic noise reduction structure is not provided. FIG. 6 is an external view schematically showing an aerodynamic noise reduction structure of a current collector according to a second embodiment of the present invention, in which (A) is a plan view, (B) is a side view, and (C) is a rear view. It is a diagram. FIG. 2 is a schematic diagram schematically showing a wind tunnel test apparatus used in an aerodynamic noise reduction effect test using an aerodynamic noise reduction structure of a current collector according to an embodiment of the present invention. It is a figure which shows the test result and test situation of the aerodynamic noise reduction effect test by the aerodynamic noise reduction structure of the current collector based on the Example of this invention, (A)-(C) is a graph which shows the test result of each specimen. and photos showing the test situation.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
An overhead contact line 1 shown in FIGS. 1, 2, and 4 to 6 is an overhead contact line installed above the railroad tracks. The overhead wire 1 is supported at support points at predetermined intervals. The contact wire 1a is an electric wire that the current collector 3 moves in contact with. The contact wire 1a supplies a load current to the vehicle 2 when the current collector 3 slides thereon. The vehicle 2 shown in FIGS. 2 and 4 to 6 is an electric vehicle such as a train or an electric locomotive. The vehicle 2 is, for example, a railway vehicle such as a Shinkansen that runs at high speed. The vehicle body 2a is a structure for loading and transporting passengers or cargo.

The current collector 3 shown in FIGS. 1 to 7 is a device for guiding electric power from the contact wire 1a to the vehicle 2. The current collector 3 includes a slide plate 4 shown in FIGS. 1 to 6, a boat body (current collection boat) 5 shown in FIGS. 1 to 7, 9 and 10, and a framework 6 shown in FIGS. 1 to 6. , the underframe 17 shown in FIG. 6, the windshield cover 18 shown in FIGS. 2 to 6, the insulator 19 shown in FIGS. 2 and 4 to 6, the aerodynamic noise reduction structure 20A shown in FIGS. 1 to 13, Equipped with 20B etc. The current collector 3 shown in FIGS. 1 to 7 is a single arm that is asymmetrical with respect to the traveling direction D of the vehicle 2 and can be used in one direction or both directions, as shown in FIGS. 1, 2, and 6. It is a type pantograph. As shown in FIGS. 1, 2, and 6, when the current collector 3 is used in the fluttering direction in which the intermediate hinge 13 is located on the front side in the direction of travel of the vehicle 2, the aerodynamic noise becomes relatively small, and the When used in the anti-swing direction where the intermediate hinge 13 is located on the rear side, aerodynamic noise becomes relatively loud. The current collector 3 shown in FIGS. 1 to 7 is moving in a fluctuating direction in which the intermediate hinge 13 is located on the front side in the direction in which the vehicle 2 travels.

The slider plate 4 shown in FIGS. 1 to 6 is a member that slides on the contact wire 1a. As shown in FIGS. 1 and 3 to 5, the slide plate 4 is a plate-like member made of metal or carbon that extends in a direction (sleeper direction) orthogonal to the traveling direction D of the vehicle 2. The slide plates 4 are separate parts manufactured separately from the boat body 5, and are attached to the upper part of the boat body 5 with a plurality of them arranged in the length direction (sleeper direction) of the boat body 5. . The slide plate 4 is supported by an elastic body such as a spring so as to be movable relative to the boat body 5.

The boat body 5 shown in FIGS. 1 to 7, 9, and 10 is a member that supports the slide plate 4. As shown in FIGS. The boat body 5 is generally an elongated metal columnar member extending in a direction perpendicular to the contact wire 1a (sleeper direction). For example, as shown in FIG. 2, the boat body 5 is symmetrical in the front and rear with respect to the central axis of the boat body 5, and both the front and rear sides are formed in the same shape. The boat body 5 has a streamlined cross-sectional shape or a curved surface approximating a streamlined shape in order to prevent separation of the flow (airflow) F as much as possible, and is configured with a smooth curve. For example, the cross-sectional shape of the hull 5 has been smoothed using a method that combines Computational Fluid Dynamics (CFD) analysis and optimization to achieve both reduction of aerodynamic noise and stabilization of lift characteristics. This is a smooth hull (smooth shaped hull). The hull 5 shown in FIGS. 1 to 7, 9, and 10 is, for example, a pantograph hull for a Shinkansen (high speed) with improved tracking performance for the contact wire 1a. The boat body 5 includes a horn 5a and the like, as shown in FIGS. 1 to 5.

The horn 5a prevents an interruption to the contact wire 1a in a direction different from the traveling direction of the vehicle 2 among the two contact wires 1a that intersect above the switch when the vehicle 2 passes the switch. It is a member for The horn 5a is a metal member that protrudes from both longitudinal ends of the boat body 5 and has a tip curved downward as shown in FIGS. 1, 4, and 5. .

The framework 6 shown in FIGS. 1 to 6 is a member that supports the boat body 5. The frame 6 includes a link mechanism that can move vertically while supporting the boat body 5. The framework 6 includes a boat support part 7 shown in FIGS. 1 and 4 to 10, an apex cover 8 shown in FIGS. 1 to 10, an upper frame 9 shown in FIGS. 1 to 10, and a boat support part 7 shown in FIG. A link (balance rod) 10, a lower frame 11 shown in FIGS. 1, 2, and 4 to 6, a counterbalance rod 12 shown in FIG. 6, an intermediate hinge (bending portion) 13 shown in FIGS. 1 to 6, etc. It is equipped with When in use, the framework 6 is raised by the biasing force of the main spring 16 shown in FIG. 6, and when not in use (when folded), it is lowered by the driving force generated by the cylinder device against the biasing force of the main spring 16. .

The boat support section 7 shown in FIGS. 1, 4 to 10 is a part that supports the boat body 5. The boat support section 7 pushes up the boat body 5 horizontally with respect to the overhead wire 1 and provides a buffering effect to the boat body 5 by a spring. The boat support section 7 maintains the balance of the boat body 5 and improves the ability to follow the contact wire 1a. The boat support part 7 is supported on the top of the upper frame 9, as shown in FIGS. 1, 2, and 4 to 9.

The vertex cover 8 shown in FIGS. 1 to 10 is a member that covers the boat support portion 7. As shown in FIG. 6, the apex cover 8 is arranged at the upper end of the upper frame 9 so as to cover the hinge part (apex hinge part) that rotatably connects the upper frame 9 and the boat support link 10 to the boat support part 7. It is removably attached to the top (top), and is formed in a shape that does not obstruct the flow F, as shown in FIGS. 1, 2, and 7 to 9. The apex cover 8 prevents the flow F from entering the boat support portion 7 and generating large aerodynamic noise, and also prevents air resistance from increasing. The vertex cover 8 is, for example, a covering member made of non-flammable or flame-retardant metal or fiber-reinforced plastics (FRP). The vertex cover 8 is a member having a substantially U-shaped planar shape as shown in FIG. 8, and a substantially U-shaped vertical cross-sectional shape as shown in FIG. The vertex cover 8 includes an upper surface part 8a shown in FIGS. 7 to 11 and 13, a lower surface part 8b shown in FIGS. 7, 9 and 10, and a side surface part 8c shown in FIGS. 7 and 9 to 13. The back surface portion 8d shown in FIGS. 7 to 9, the upper edge portion (upper edge) 8e shown in FIGS. 7 to 11 and 13, and the lower edge portion (lower edge) shown in FIGS. 8f, a mounting portion 8g shown in FIGS. 7 to 10, and a through hole 8h shown in FIG. 10. As shown in FIG. 7, the vertex cover 8 is a polyhedron composed of an upper surface portion 8a, a lower surface portion 8b, a side surface portion 8c, and a back surface portion 8d, and as shown in FIG. 10, two adjacent faces of the polyhedron form an upper edge angle. It intersects at the portion 8e and the lower ridge corner portion 8f.

The upper surface portion 8a shown in FIGS. 7 to 11 and 13 is a portion that constitutes the upper surface of the vertex cover 8. As shown in FIGS. As shown in FIGS. 7 and 9, the upper surface portion 8a is formed into a flat inclined surface so as to have approximately the same height (flushness) as the upper surface of the upper frame 9. As shown in FIGS. The lower surface portion 8b shown in FIGS. 7, 9, and 10 is a portion that constitutes the lower surface of the vertex cover 8. As shown in FIG. 10, the lower surface portion 8b has a front side that is approximately the same height (flush) as the lower surface of the upper frame 9, and a rear side that is higher than the lower surface of the upper frame 9 (projects downward). As shown, it is formed into a flat inclined surface that slopes at a plurality of inclination angles from the front side to the rear side.

The side portions 8c shown in FIGS. 7 and 9 to 13 constitute both side surfaces of the apex cover 8. As shown in FIG. As shown in FIGS. 7 and 10, the side parts 8c are detachably attached to both sides of the upper end of the upper frame 9 so as to sandwich both sides of the upper end of the upper frame 9. As shown in FIGS. 7 and 9, the side surface portion 8c is a flat plate-shaped portion with rounded front and rear sides. The back surface portion 8d shown in FIGS. 7 to 9 is a portion that constitutes the back surface of the apex cover 8. As shown in FIGS. As shown in FIGS. 8 and 9, the back surface portion 8d has a substantially spherical appearance, and has an upper surface portion 8a, It is formed at the same height (flush) as the lower surface part 8b and the side surface part 8c.

The upper edge portion 8e shown in FIGS. 7 to 11 and 13 is a portion where the upper surface portion 8a and the side surface portion 8c intersect. The upper ridge corner portion 8e is formed linearly along the length direction of the upper surface portion 8a and the side surface portion 8c, as shown in FIGS. 7 to 9, and has an angular cross-sectional shape as shown in FIG. has been done. The lower edge portion 8f shown in FIGS. 7, 9, and 10 is a portion where the lower surface portion 8b and the side surface portion 8c intersect. As shown in FIGS. 7 and 9, the lower ridge portion 8f is formed in a curved and linear shape along the length direction of the lower surface portion 8b and the side surface portion 8c, and has a cross-sectional shape as shown in FIG. is formed at the corner.

The mounting portion 8g shown in FIGS. 7 to 10 is a portion to which the aerodynamic noise reduction structures 20A and 20B are mounted. As shown in FIG. 10, the mounting portion 8g is a recess formed at a predetermined depth in the upper surface portion 8a and the side surface portion 8c, and is formed by cutting out the upper edge portion 8e as shown in FIGS. 8 to 10. It is formed with a predetermined length and width. As shown in FIGS. 8 and 9, the mounting portion 8g has a rectangular planar shape and side surface shape so that the aerodynamic noise reduction structures 20A and 20B are removably fitted therein. The through hole 8h shown in FIG. 10 is a portion that penetrates the vertex cover 8. The through hole 8h is formed to penetrate the side surface 8c of the vertex cover 8.

The upper frame 9 shown in FIGS. 1 to 10 is a member rotatably connected to the boat support section 7. The upper frame 9 is a cylindrical member that constitutes the upper half of the framework 6, and accommodates a boat support link 10 shown in FIG. 6 therein. One end of the upper frame 9 is rotatably connected to the boat support section 7, and the other end of the upper frame 9 is rotatably connected to the lower frame 11. The boat support link 10 is a member that maintains the boat body 5 and the boat support section 7 in a predetermined posture. One end of the boat support link 10 is rotatably connected to the boat support part 7, and the other end of the boat support link 10 is rotatably connected to the lower frame 11.

The lower frame 11 shown in FIGS. 1 to 10 is a member rotatably connected to the underframe 17. The lower frame 11 is a cylindrical member that constitutes the lower half of the framework 6, and accommodates a counterbalance rod 12 shown in FIG. 6 therein. One end of the lower frame 11 is rotatably connected to the upper frame 9, and the other end of the lower frame 11 is connected to the main shaft 14. The counterbalance rod 12 is a member for adjusting the locus of vertical displacement of the boat body 5. One end of the balance rod 12 is rotatably connected to the upper frame 9, and the other end of the balance rod 12 is rotatably connected to the main shaft 14. The intermediate hinge 13 shown in FIGS. 1 to 6 is a portion that rotatably connects the upper frame 9 and the lower frame 11. The intermediate hinge 13 functions as a joint that connects the upper frame 9 and the lower frame 11, as shown in FIG.

The main shaft 14 shown in FIG. 6 is a member that moves the framework 6 up and down. The main shaft 14 operates in conjunction with the framework 6, and moves the framework 6 up and down by rotating in forward and reverse directions. The main shaft 14 is rotatably supported by the underframe 17 and rotates together with the lower end of the lower frame 11. The lever portion 15 is a portion that converts linear motion into rotational motion. The lever portion 15 rotates together with the main shaft 14 using the main shaft 14 as a fulcrum. The main spring 16 is a member that applies a lifting force to the framework 6. The main spring 16 is a push-up spring that urges the main shaft 14 so that the main shaft 14 rotates and the framework 6 rises. The other end of the main spring 16 is rotatably connected to the lever portion 15.

The underframe 17 shown in FIG. 6 is a member that supports the framework 6. The underframe 17 supports the base of the framework 6 and is installed on the roof of the vehicle body 2a via an insulator 18. The underframe 17 supports an elevating mechanism section that includes a main shaft 14, a lever section 15, a main spring 16, and the like for moving the frame 6 up and down.

The windshield cover 18 shown in FIGS. 2 to 6 is a member that covers the underframe 17. As shown in FIG. 6, the windshield cover 18 covers the main shaft 14, lever portion 15, main spring 16, underframe 17, etc., and has a shape that does not impede the flow F as shown in FIGS. 2 and 3. is formed. The windshield cover 18 prevents the flow F from entering into the underframe 17 and generating large aerodynamic noise, and also prevents air resistance from increasing. The windshield cover 18 is, for example, a covering member made of FRP.

The insulator 19 shown in FIGS. 2 and 4 to 6 is a member that electrically insulates between the vehicle body 2a and the underframe 17. The insulator 19 is, for example, a low-noise insulator formed in a shape that has the effect of suppressing the generation of aerodynamic noise. The insulator 19 has a substantially elliptical cross section when cut along a horizontal plane in order to suppress the release of vortices generated at the rear edge of the insulator 19. The insulators 19 support the bottom surfaces of the underframe 17 near both edges.

The aerodynamic noise reduction structures 20A and 20B shown in FIGS. 1 to 13 are structures that reduce aerodynamic noise generated from the current collector 3. The aerodynamic noise reduction structures 20A and 20B reduce aerodynamic noise generated from the aerodynamic noise generation source of the current collector 3. Here, the aerodynamic sound source is the upper edge portion 8e where the adjacent top surface portion 8a and side surface portion 8c of the apex cover 8 intersect. The aerodynamic noise reduction structures 20A and 20B are plates with channels made of synthetic resin or metal that are removably attached to the attachment portion 8g of the vertex cover 8, and as shown in FIGS. It is formed to have substantially the same length, width, and depth as the length, width, and depth. The aerodynamic sound reduction structures 20A and 20B have a plate thickness of, for example, 10 mm. As shown in FIG. 7, the aerodynamic noise reduction structures 20A and 20B have a symmetrical structure with respect to the center line of the apex cover 8 when attached to the apex cover 8.

The aerodynamic noise reduction structures 20A and 20B constitute a part of the apex cover 8 when attached to the mounting portion 8g of the apex cover 8, and the aerodynamic noise reduction structures 20A and 20B form a part of the top surface, side surface and The upper edge portion constitutes a portion of the upper surface portion 8a, side portion 8c, and upper edge portion 8e of the vertex cover 8, respectively. As shown in FIGS. 7 and 9 to 11, the top surfaces of the aerodynamic noise reduction structures 20A and 20B are at the same height (flush) as the top surface portion 8a of the apex cover 8. As shown in FIGS. 9 and 11, the upper ends of the aerodynamic noise reduction structures 20A and 20B near the back surface 8d of the apex cover 8 are formed as flat inclined surfaces. As shown in FIGS. 7, 8, and 10, the aerodynamic noise reduction structures 20A and 20B have side surfaces that are at the same height (flush) as the side surface 8c of the apex cover 8. It is formed on a flat surface. The aerodynamic noise reduction structures 20A and 20B are both the same structure, and below, one aerodynamic noise reduction structure 20A will be explained, and detailed explanation of the other aerodynamic noise reduction structure 20B will be omitted. The aerodynamic noise reduction structures 20A and 20B include joint portions 21a to 21d shown in FIGS. 9 to 11, through holes 22 shown in FIGS. 9 and 10, and a plurality of openings 23 shown in FIGS. 10 to 13. The cross section 25 shown in FIGS. 10, 12 and 13, and the fixing section 26 shown in FIGS. 7 to 10 are provided.

The joint parts 21a to 21d shown in FIGS. 9 to 11 are parts that are joined to the mounting part 8g of the vertex cover 8. As shown in FIGS. 9 and 11, the joint part 21a is joined to the front wall of the mounting part 8g, the joint part 21b is joined to the rear wall of the mounting part 8g, and the joint part 21c is joined to the rear wall of the mounting part 8g. As shown in FIG. 10, the joint portion 21d is joined to the bottom of the mounting portion 8g. The through hole 22 shown in FIGS. 9 and 10 is a portion that penetrates the aerodynamic noise reduction structures 20A and 20B. The through hole 22 is formed at a position corresponding to the through hole 8h of the vertex cover 8, as shown in FIG.

The opening 23 shown in FIGS. 10 to 13 is a portion that allows the flow F to flow into the interior of the vertex cover 8 and causes the flow F that has flowed in to flow out from the interior of the vertex cover 8. As shown in FIGS. 7 to 11, a plurality of openings 23 are formed on the top surface portion 8a and side surface portion 8c of the aerodynamic noise reduction structures 20A and 20B. The opening 23 is configured such that the flow around the apex cover 8 flows into the inside of the apex cover 8 and the flow that has flowed into the inside of this apex cover 8 flows out from this apex cover 8 to the periphery of this apex cover 8. It functions as an inlet and an outlet for the flow F. The opening 23 is formed in the top surface 8a and side surface 8c of the vertex cover 8 along the upper edge 8e of the vertex cover 8, as shown in FIGS. 7 to 9 and 11. The openings 23 have a circular shape and are arranged in two rows in parallel at intervals in the length direction and width direction of the top surface portion 8a and side surface portion 8c.

As shown in FIGS. 10 to 13, the opening 23 extends in the width direction of the top surface portion 8a (the width direction of the aerodynamic noise reduction structures 20A and 20B (hereinafter referred to as the X-axis direction)), and in the top surface portion 8a and the side surface portion 8c. (the length direction of the aerodynamic noise reduction structures 20A, 20B (hereinafter referred to as the Y-axis direction)) and the height direction of the side surface portion 8c (the height direction of the aerodynamic noise reduction structures 20A, 20B (hereinafter referred to as the Z-axis direction)). They are formed at intervals in the axial direction). For example, as shown in FIG. 11, the opening 23 has a diameter φ=2 mm, and the distance between adjacent openings 23 in the length direction (distance between centers) d ₁ =5.2 mm, The distance between adjacent openings 23 in the width direction and height direction (distance between centers) d ₂ =4.0 mm. For example, 54 openings 23 are formed in the upper surface part 8a as shown in FIG. 11(A), and 48 openings 23 are formed in the side surface part 8c as shown in FIG. 11(B).

Flow paths 24a to 24c shown in FIGS. 10 to 13 are portions that connect a plurality of openings 23 to each other. The channels 24a to 24c are regularly arranged inside the vertex cover 8 in three axial directions (X-axis direction, Y-axis direction, and Z-axis direction). The flow paths 24a to 24c connect the plurality of openings 23 inside the vertex cover 8, and allow the flow F to pass from one opening 23 to another opening 23. The flow paths 24a to 24c are arranged at intervals in a plurality of directions inside the vertex cover 8, and direct the flow F flowing in from the opening 23 of the high pressure section on the surface of the vertex cover 8 to the flow paths 24a to 24c. It is made to flow out from the opening 23 of the low pressure section. The flow paths 24a to 24c, for example, direct airflow flowing into the interior of the vertex cover 8 from the opening 23 of a high pressure region such as a stagnation point on the surface of the vertex cover 8 to a low pressure region such as near a peeling point on the surface of the vertex cover 8. Let it flow naturally from the opening 23 of the.

The channels 24a to 24c extend in three axial directions inside the vertex cover 8, as shown in FIGS. 10, 12, and 13, and the channels 24a to 24c extending in each axial direction intersect at an intersection 25. . As shown in FIGS. 10 to 13, the flow path 24a is a pipe (horizontal pipe) that extends linearly in the X-axis direction inside the vertex cover 8, and is arranged perpendicularly to the side surface 8c. ing. As shown in FIGS. 11 and 12, the flow path 24b is a pipe (horizontal pipe) that extends linearly in the Y-axis direction inside the apex cover 8, and is perpendicular to the flow path 24a and extends from the side surface. They are arranged parallel to the portion 8c. As shown in FIGS. 10, 11, and 13, the flow path 24c is a pipe (vertical pipe) that extends linearly in the Z-axis direction inside the vertex cover 8, and is perpendicular to the flow paths 24a and 24b. Moreover, they are arranged parallel to the side surface portion 8c.

The intersection portion 25 shown in FIGS. 10, 12, and 13 is a portion where the channels 24a to 24c intersect. The intersection 25 connects the flow paths 24a to 24c such that the flow F can mutually pass between the flow paths 24a to 24c. The intersection portions 25 are formed at intervals inside the vertex cover 8, and are regularly arranged at intervals in the X-axis direction, Y-axis direction, and Z-axis direction similarly to the flow paths 24a to 24c. There is. The intersection 25 connects the channels 24a to 24c so that the channels 24a to 24c are perpendicular to each other so that the flow F can freely pass through the channels 24a to 24c. As shown in FIG. 11, the intersection 25 is arranged in the X-axis direction, Y-axis direction, and Z-axis direction with this intersection 25 as the origin, assuming a three-dimensional orthogonal coordinate system with the intersection 25 as the origin. Flow paths 24a to 24c extend therein.

The fixing portion 26 shown in FIGS. 7 to 10 is a means for fixing the aerodynamic noise reduction structures 20A and 20B. As shown in FIG. 10, the fixing part 26 is a fastening member such as a bolt having a male threaded part that engages with a female threaded part formed on the side surface of the boat support part 7. The fixing portion 26 is inserted into the through hole 22 of the aerodynamic noise reduction structure 20A, 20B and the through hole 8h of the apex cover 8, and detachably fixes the aerodynamic noise reduction structure 20A, 20B to the boat support portion 7. The fixing part 26 fastens the aerodynamic noise reduction structures 20A and 20B to the boat support part 7 together with the apex cover 8 so that the apex cover 8 is sandwiched between the aerodynamic noise reduction structures 20A and 20B and the boat support part 7 (co-tightened together). )are doing.

Next, the operation of the aerodynamic noise reduction structure of the current collector according to the first embodiment of the present invention will be explained.
FIG. 14 is a photograph showing changes in the flow field in a wind tunnel test when a porous material is applied to the surface of a cylinder. The aerodynamic noise reduction structure shown in FIG. 14(A) is a porous material that simulates the aerodynamic noise reduction structures 20A and 20B shown in FIG. 11. A porous material has a three-dimensional skeletal network structure in which minute pores are formed in the walls of the pores, and the pores communicate with each other, such as continuous pores. The porous material is a rigid porous material such as a flame retardant or non-combustible metal porous material.

If the surface of the cylinder in the flow field shown in Fig. 14(A) is not equipped with an aerodynamic sound reduction structure, the surface of the cylinder in the flow field shown in Fig. 14(A) is slightly upstream of the maximum width part of the cylinder as shown in Fig. 14(B) and (C). At the separation point on the surface, the flow F in the direction of the arrow separates, and air alternately flows around the downstream side of this cylinder. Therefore, a Karman vortex is generated by the interaction of vortices generated from the separation shear layer on the surface of the cylinder, and noise and vibration are generated due to this Karman vortex. On the other hand, when the surface of the cylinder in the flow field shown in FIG. 14(A) is equipped with an aerodynamic noise reduction structure, the flow F is inside the aerodynamic noise reduction structure as shown in FIGS. 14(D) and (E). The flow F in the aerodynamic noise reduction structure naturally flows out from a low pressure area such as near the separation point. As a result, the flow field is stabilized, vortex shedding is weakened, and aerodynamic noise is reduced.

When the vehicle 2 travels in the traveling direction D shown in FIGS. 1 to 5, separation of the flow F occurs at the linear upper corner portion 8e of the current collector 3 shown in FIGS. 7 to 10. Flow F enters from an opening 23 in a high pressure area, such as a stagnation point on the surface of the apex cover 8 shown in FIGS. 7-11. When the flow F flows in from the opening 23 of the high pressure section, the flow F passes through the flow paths 24a to 24c and the intersection 25 shown in FIGS. 10 to 13, and the surface of the apex cover 8 shown in FIGS. Flow F naturally flows out from the opening 23 in the low pressure area near the separation point. As a result, the flow field is stabilized, vortex shedding is weakened, and aerodynamic noise is reduced.

Next, a method for manufacturing the aerodynamic noise reduction structure for a current collector according to the first embodiment of the present invention will be described.
The aerodynamic noise reduction structures 20A and 20B shown in FIGS. 1 to 13 are manufactured using a shaping device, machining, molding, or casting. Here, the modeling device is a device that manufactures objects of arbitrary shapes. The modeling device is, for example, 3DCAD (3 Dimensional Computer Aided Design), which uses a computer to design a three-dimensional shape in a virtual three-dimensional space, or 3DCG (which uses a computer to create a three-dimensional shape in a virtual three-dimensional space). 3D printers that manufacture objects based on 3D digital models made up of 3D data generated by 3D computer graphics.

When manufacturing the aerodynamic sound reduction structures 20A and 20B using a resin 3D printer, for example, a stereolithography method in which the object is manufactured by irradiating a liquid resin with ultraviolet rays and curing it little by little, or a method in which the resin melted with heat is gradually manufactured. Fused Deposition Modeling (FDM) method is used to manufacture objects by stacking them on top of each other.The sheet material is cut into the cross-sectional shape of the object, and each layer is laminated by gluing and welding, and the object is cured by irradiation with ultraviolet rays or heating. Sheet lamination method for manufacturing, powder fixing method for manufacturing objects by spraying adhesive on powdered resin, material injection method for manufacturing objects by spraying liquid photocurable resin or wax from a nozzle and curing it by irradiating ultraviolet rays or heating. The aerodynamic noise reduction structures 20A and 20B are manufactured by the following methods.

When manufacturing the aerodynamic sound reduction structures 20A and 20B using a metal 3D printer, for example, selective laser sintering (SLS) is used, in which metal powder is irradiated with laser light and the metal powder is sintered to manufacture the object. ) method), Direct metal laser sintering (DMLS) method, in which a metal powder is irradiated with ytterbium laser light instead of the carbon dioxide laser in the laser sintering method, and the metal powder is sintered to produce an object. ), selective laser melting (SLM) method, in which a metal powder is irradiated with a laser beam to melt the metal powder to produce an object; a metal powder is irradiated with an electron beam to melt the metal powder, and an object is manufactured. Electron Beam Melting (EBM) method for manufacturing objects; molten metal lamination method for manufacturing objects by irradiating a metal wire with an electron beam to melt the metal wire instead of metal powder in the electron beam melting method; The aerodynamic sound reduction structures 20A and 20B are manufactured by a laser engineered net shaping (LENS) method, etc., in which metal powder is dropped into a molten pool from a nozzle and sintered with laser light to manufacture an object.

When manufacturing the aerodynamic noise reduction structures 20A and 20B by machining, a plate-like member shown in FIG. 11 is manufactured by cutting a metal or synthetic resin plate material, and a hole is drilled in this plate-like member. The opening 23 and the channels 24a to 24c are manufactured by doing this. For example, it is manufactured by drilling holes using a long drill in the Y-axis direction and then blocking unnecessary flow channels. When manufacturing the aerodynamic noise reduction structures 20A and 20B by machining or molding, a dividing plate that divides the flow path 24b in the Y-axis direction into upper and lower halves is manufactured in three layers, and these dividing plates are stacked. After integration, the opening 23 and flow channels 24a, 24c are manufactured by drilling. When manufacturing the aerodynamic noise reduction structures 20A and 20B by casting, they are manufactured by pouring molten metal into a mold in which openings 23 and channels 24a to 24c are formed in advance.

The aerodynamic noise reduction structure of the current collector and the manufacturing method thereof according to the first embodiment of the present invention have the following effects.
(1) In the first embodiment, the plurality of openings 23 allow the flow F to flow into the inside of the vertex cover 8, and the plurality of openings 23 allow the flow F to flow out from the inside of the vertex cover 8. A plurality of channels 24a to 24c connect the plurality of openings 23 to each other. Further, in the first embodiment, a plurality of channels 24a to 24c are arranged inside the apex cover 8 at intervals in a plurality of directions, and inflow flows from the opening 23 of the high pressure section on the surface of the apex cover 8. A plurality of channels 24a to 24c allow the flow F to flow out from the opening 23 of the low pressure portion on the surface of the vertex cover 8. Therefore, aerodynamic noise can be reduced by providing flow paths 24a to 24c that allow the flow F to naturally flow in and out on the member surface. In addition, the aerodynamic sound reduction effect can be achieved with a structure that is easier to apply than conventional porous materials, and the conventional porous materials can be easily replaced by members with flow channels.

(2) In the first embodiment, a plurality of channels 24a to 24c extend in triaxial directions inside the vertex cover 8, and the channels 24a to 24c extending in each axial direction intersect at an intersection 25. Therefore, it can be applied to the apex cover 8 by simply drilling holes in the member, which is easier to implement than porous materials, and the simple structure with a simple shape can reduce aerodynamic noise. . Further, since the hole is formed in the base material, it will not peel off from the vertex cover 8, and reliability can be improved compared to adhesion of a porous material, and it can be easily applied to the vertex cover 8.

(3) In the first embodiment, a plurality of openings 23 are formed in the top surface portion 8a and side surface portion 8c of the vertex cover 8 along the upper edge portion 8e of the vertex cover 8. Therefore, generation of aerodynamic noise from the vertex cover 8, which is a main source of aerodynamic noise in the current collector 3, can be suppressed.

(4) In this first embodiment, the aerodynamic noise reduction structures 20A and 20B are shaped using a shaping device. Therefore, high-strength resin or metal can be output using a modeling device such as a 3D printer and integrally molded with the members constituting the current collector 3. In addition, it can be easily attached to three-dimensional curved surfaces, etc., which are difficult to attach using adhesive with conventional porous materials. As a result, the aerodynamic noise reduction structures 20A, 20B can be easily manufactured, and the aerodynamic noise reduction structures 20A, 20B can be easily applied to the current collector 3.

(Second embodiment)
In the following, parts that are the same as those shown in FIGS. 1 to 13 are given the same reference numerals and detailed explanations will be omitted.
Unlike the aerodynamic noise reduction structures 20A and 20B shown in FIG. 11, the aerodynamic noise reduction structures 20A and 20B shown in FIG. is provided with an opening 23. For example, 222 openings 23 are formed in the side surface 8c as shown in FIG. 15(B). This second embodiment has the same effects as the first embodiment.

Next, embodiments of the invention will be described.
(Wind tunnel test)
As shown in FIG. 17, specimens A to C were attached to the apex cover of an actual Shinkansen pantograph equipped with a smoothed hull, and aerodynamic noise was evaluated through wind tunnel tests. The wind tunnel test used an open-body wind tunnel test device provided by the Railway Technical Research Institute. As shown in Figure 16 , with an actual Shinkansen pantograph supported on the first model support cart of the wind tunnel measurement section of the wind tunnel test equipment, air at a wind speed of 360 km/h is supplied from the blowing nozzle to the Shinkansen pantograph in the wind tunnel measurement section. The aerodynamic sound generated from the Shinkansen pantograph due to the air flow was measured using an aerodynamic sound measurement microphone.

(Specimen)
Specimen A shown in FIG. 17(A) is a vertex cover of a current Shinkansen pantograph. In the specimen A, a plate without an opening 23 is attached to the attachment portion 8g of the vertex cover 8 shown in FIG. In the specimen B shown in FIG. 17(B), an opening is formed on substantially the entire side surface of the apex cover of a current Shinkansen pantograph. Specimen B is a second embodiment shown in FIG. 15, in which a plate with a flow path having an opening 23 on substantially the entire surface of the side surface 8c is mounted on the mounting portion 8g of the vertex cover 8. In the specimen C shown in FIG. 17(C), openings are formed only in two rows located at the corners of the vertex cover of the current Shinkansen pantograph. Specimen C is the first embodiment shown in FIG. 11, in which the apex cover 8 is attached to a plate with flow channels having only two rows of openings 23 in the top surface portion 8a and the side surface portion 8c along the upper edge portion 8e. It is attached to part 8g. In specimens B and C shown in FIGS. 17(B) and 17(C), channels with a diameter of 2 mm are formed in three axes perpendicular to a plate material having a thickness of 10 mm.

(Aerodynamic sound measurement results)
FIG. 17 shows the measurement results of aerodynamic noise of specimens A to C in a wind tunnel test. The vertical axis shown in FIG. 17 is the noise level OA value (dB(A)). As a result, it was confirmed that the OA value of specimen B could be reduced by approximately 0.2 dB compared to specimen A. Furthermore, it was confirmed that the OA value of specimen C could be reduced by approximately 0.4 dB compared to specimen A. Furthermore, it was confirmed that specimen C had a higher aerodynamic sound reduction effect than specimen B.

(Other embodiments)
This invention is not limited to the embodiments described above, and various modifications and changes can be made as described below, and these are also within the scope of this invention.
(1) Although this embodiment has been described using a single-arm pantograph as an example of the current collector 3, the present invention can also be applied to other types of pantographs such as a diamond-shaped pantograph. In addition, in this embodiment, the case where the current collector 3 moves in the fluttering direction in which the intermediate hinge 13 is located on the front side in the traveling direction of the vehicle 2 has been described as an example; The present invention can also be applied to the case where the current collector 3 moves in the anti-swinging direction where the current collector 13 is located. Furthermore, in this embodiment, a case has been described in which the aerodynamic sound generation source is a ridge corner where a plurality of adjacent surfaces intersect. The present invention can also be applied to sources. Similarly, in this embodiment, the upper edge corner portion 8e of the vertex cover 8 has been described as an example of the aerodynamic noise generation source of the current collector 3, but the present invention is not limited to the upper edge corner portion 8e. For example, the lower edge 8f of the apex cover 8, the upper edge or lower edge of the intermediate hinge 13, the upper edge or lower edge of the windshield cover 18, or the joint between the windshield cover 18 and the insulator 19. The present invention can also be applied to the case of reducing aerodynamic noise generated from aerodynamic noise sources such as.

(2) In this embodiment, the case in which the cross-sectional shape of the upper edge corner portion 8e of the vertex cover 8 is a square has been described as an example, but the present invention also applies when the cross-sectional shape of the upper edge corner portion 8e is round. can be applied. Further, in this embodiment, the case where the openings 23 are arranged in two rows in the length direction of the top surface part 8a and the side surface part 8c of the vertex cover 8 has been described as an example. The present invention is not limited to this arrangement. For example, the present invention can also be applied to a case where one row or three or more rows of openings 23 are arranged in the length direction of the top surface portion 8a and side surface portion 8c of the vertex cover 8. Further, in this embodiment, the case where the shape of the opening 23 is circular has been described as an example, but the present invention can be applied. Further, in this embodiment, the case where the aerodynamic noise reduction structures 20A and 20B are fastened together with the apex cover 8 to the boat support part 7 using the fixing part 26 has been described as an example, but the present invention is not limited to such a fastening method. It's not something you do. For example, the present invention is also applicable to a case where a female threaded portion that engages with a male threaded portion of the fixing portion 26 is formed on the side surface 8c of the apex cover 8, and the aerodynamic noise reduction structures 20A and 20B are fastened to the apex cover 8 by the fixing portion 26. can do.

(3) In this embodiment, the case where the openings 23 are arranged in parallel at equal intervals in the X-axis direction, Y-axis direction, and Z-axis direction has been described as an example. The present invention can also be applied to a case where the openings 23 are arranged in a staggered manner in the axial direction. Further, in this embodiment, the case where the flow paths 24a to 24c are arranged in the X-axis direction, Y-axis direction, and Z-axis direction has been described as an example, but the openings 23 where the flow F flows in and out are connected. The present invention can also be applied to the case where the channels 24a to 24c are arranged in one direction or two directions. Furthermore, in this embodiment, the case where the channels 24a to 24c intersect at right angles at the intersection 25 has been described as an example, but this also applies to the case where the channels 24a to 24c intersect at an arbitrary angle at the intersection 25. The invention can be applied.

1 Overhead wire 1a Contact wire 2 Vehicle 2a Car body 3 Current collector 4 Slide plate 5 Boat body 6 Frame 7 Boat support section 8 Vertex cover 8a Top section 8b Bottom section 8c Side section 8d Back section 8e Upper ridge corner (aerodynamic sound source)
8f Lower edge part 8g Mounting part 8h Female thread part 9 Upper frame 11 Lower frame 13 Intermediate hinge 17 Underframe 20A, 20B Aerodynamic noise reduction structure 21a to 21d Joint part 22 Through hole 23 Opening part 24a to 24c Channel 25 Intersection part 26 Fixed part F Flow D Direction of movement

Claims (4)

An aerodynamic noise reduction structure for a current collector that reduces aerodynamic noise generated from the current collector,
a plurality of openings for allowing flow to flow into the interior of the apex cover of the current collector and for allowing the flow to flow out from the interior of the apex cover ;
a plurality of flow paths connecting the plurality of openings,
The plurality of flow paths are arranged at intervals in a plurality of directions inside the apex cover , and the flow flowing in from the opening of the high pressure section on the surface of the apex cover is directed to the low pressure section on the surface of the apex cover. flow out from the opening of
The top surface part and side surface part of the aerodynamic noise reduction structure constitute a part of the vertex cover so as to be at the same height as the top surface part and side surface part of the vertex cover,
The plurality of openings are formed in the top and side surfaces of the vertex cover along the upper edge corner of the vertex cover;
Aerodynamic noise reduction structure for current collector featuring: The aerodynamic noise reduction structure of the current collector according to claim 1,
The plurality of channels extend in triaxial directions inside the apex cover, and the channels extending in each axial direction intersect at an intersection,
Aerodynamic noise reduction structure for current collector featuring: In the aerodynamic noise reduction structure of the current collector according to claim 1 or 2,
The aerodynamic noise reduction structure is attached to a mounting portion formed by cutting out an upper edge corner portion of the apex cover,
A fixing part that removably fixes the aerodynamic noise reduction structure to the boat support part together with the apex cover so as to sandwich the apex cover between the boat support part covered by the apex cover and the aerodynamic noise reduction structure. be prepared,
Aerodynamic noise reduction structure for current collector featuring: A method for manufacturing an aerodynamic noise reduction structure for a current collector that reduces aerodynamic noise generated from the current collector, the method comprising:
modeling the aerodynamic sound reduction structure of the current collector according to any one of claims 1 to 3 using a modeling device;
A method for manufacturing an aerodynamic noise reduction structure for a current collector, characterized by:

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