JP2023122933A - Lift force variation suppressing structure of collector head - Google Patents

Abstract

To provide a lift force variation suppressing structure of collector heads that can suppress variation in lift force acting on collector heads of a current collecting device, by using a simple structure.SOLUTION: A lift force variation suppressing structure 23 suppresses variation in lift force acting on collector heads 8A, 8B, when the collector heads 8A, 8B receive a flow that changes lift force acting on the collector heads 8A, 8B of a line concentrator. The lift force variation suppressing structure 23 comprises apertures 24A, 24B that penetrate the collector heads 8A, 8B in a vertical direction and are open at an upper surface 8g and a lower surface 8h of the collector heads 8A, 8B. The apertures 24A, 24B are formed by being almost continuous between one end and the other end of the collector heads 8A, 8B. Thus, a flow field around the collector heads 8A, 8B varies according to discharge of a flow from a lower part to an upper part of the collector heads 8A, 8B and pressure variation of the collector heads 8A, 8B is relaxed, so that an increase in a positive lift force for lifting the collector heads 8A, 8B is suppressed.SELECTED DRAWING: Figure 6

Description

The present invention relates to a structure for suppressing changes in lift acting on a hull of a concentrator, which suppresses changes in the lift acting on the hull when the hull receives a flow that changes the lift acting on the hull.

Since the running speed of conventional lines is lower than that of the Shinkansen (registered trademark), the lift force of the pantograph, which is proportional to the square of the wind speed, has not been studied as much as the Shinkansen. As shown in FIG. 23, "aerodynamic characteristics of conventional line pantographs" describes lift force measurement examples of conventional line pantographs for each type of pantograph (see, for example, Non-Patent Document 1). Here, the vertical axis shown in FIG. 23 is lift (N), and the horizontal axis is wind speed (m/s). In the "aerodynamic characteristics of conventional line pantographs", conventional line pantographs (rhombic, lower frame cross type) lift at 100 km/h during normal running is about several N to 20 N, which is a big problem. It is confirmed that the value is not

On the other hand, there is concern about increased lift in strong winds. When the wind is strong, as shown in FIG. 24, the pantograph is exposed to a flow that is blown up diagonally from below in addition to the traveling wind due to the side wind that is blown up by the shoulder of the vehicle (see, for example, Non-Patent Document 2). "Lift characteristics of pantographs on conventional lines in crosswinds" and "Evaluation of the effect of external dimensions of the hull on the lift characteristics of pantographs on conventional lines in crosswind environments" show that the conventional line pantographs It has been confirmed that the lift is significantly increased by setting the roll angle and the yaw angle and measuring the lift (for example, see Non-Patent Documents 3 and 4).

In the "Evaluation of the influence of the external dimensions of the hull on the lift characteristics of conventional line pantographs in a crosswind environment", the lift force of conventional line pantographs subjected to crosswinds was measured. As shown in FIGS. 25A to 25C, a conventional line pantograph is tilted and supported at a roll angle φ on the turntable of the wind tunnel measurement section of the wind tunnel test apparatus. In this state, the turntable is rotated at a yaw angle θ, and the lift force of the pantograph for conventional lines is measured when air with a wind speed of 30 m/s (108 km/h) is blown. Here, the vertical axis shown in FIG. 25(D) is the lift force F _PL [N] acting on the pantograph, and the horizontal axis is the crosswind angle θ [°] (in this figure, the is defined to be 180°). As shown in Fig. 25(D), the lift is about 20 N when the roll angle is 0° and the vehicle is not subject to crosswinds, but the lift is about 80 N at the yaw angle of 56°. ° has reached about 130N. Therefore, it is important to suppress an increase in lift when the pantograph receives a crosswind.

Mitsuo Aboshi, 2 others, "Aerodynamic Characteristics of Conventional Line Pantographs", Report of Railway Technical Research Institute, Kenyusha, 1992, Vol.6, No.9, p.5-10

Yuhei Noguchi, et al., ``Numerical simulation of crosswind aerodynamic characteristics in a wind tunnel test'', RTRI Report, Kenyusha, 2017, Vol.31, No.9, p.11-16

Mikiyuki Kobayashi, 6 others, ``Lift characteristics of conventional line pantographs with crosswinds'', Proceedings of the Japan Railway Engineering Symposium, J-RAIL, December 2018, Vol.

Tatsushi Isono, 3 others, ``Evaluation of the influence of the outer dimensions of the hull on the lifting force characteristics of the pantograph for conventional lines under crosswind conditions'', The 28th Transportation and Logistics Division Conference, TRANSLOG2019, November 2019, Volume 2019.28

The increase in lift caused by crosswinds is thought to be caused by two factors: (1) increase in frame lift and (2) increase in hull lift. Of these, "(2) increase in lift of the hull" is caused by the updraft acting on the hull from diagonally below, and "(A) positive pressure is generated due to the stagnant flow on the bottom side of the hull." This is thought to be caused by two factors: "(B) the flow separates on the upper side of the hull and a vortex is generated, which causes a negative pressure". Therefore, it is important to take measures against (A) and (B) above in order to suppress "(2) increase in lift of the hull" in the event of a crosswind.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a structure for suppressing changes in lift applied to a boat of a current collector, capable of suppressing changes in lift acting on the boat of a current collector with a simple structure.

The present invention solves the above-described problems by means of solutions as described below.
In addition, although the code|symbol corresponding to embodiment of this invention is attached|subjected and demonstrated, it does not limit to this embodiment.
In the invention of claim 1, as shown in FIGS. A lift change suppression structure for a hull that suppresses changes in the lift acting on the hull when the hull receives the lift force change suppression structure. ) is provided with openings (24A, 24B) that open at the hull lift change suppression structure (23).

According to a second aspect of the invention, in the lift change suppression structure of the boat body according to the first aspect, as shown in FIGS. The structure for suppressing lift change of the hull is characterized by being formed substantially continuously to the hull.

According to a third aspect of the invention, in the structure for suppressing lift change in a boat body according to the first aspect, the opening is formed in the central portion of the boat body, as shown in FIG. It is a lift force change suppression structure for the hull.

According to a fourth aspect of the invention, in the lift change suppression structure of the first aspect of the invention, as shown in FIG. 10, the openings are formed at one end and the other end of the boat. The structure for suppressing lift change of the hull is characterized by:

According to the invention of claim 5, in the structure for suppressing lift change of the boat body according to any one of claims 1 to 4, as shown in FIGS. The lift force change suppression structure for the hull is characterized by including positive pressure relief portions (25A, 25B) that relieve positive pressure (P _P ).

According to a sixth aspect of the invention, in the structure for suppressing lift change in the hull according to the fifth aspect, the positive pressure reducing portion alleviates blockage of a flow directed upward from below on the lower surface side of the hull. It is a lift force change suppression structure of the hull.

According to a seventh aspect of the invention, in the lift force change suppression structure of the boat body according to the fifth or sixth aspect, as shown in FIGS. , and a lower portion (25a) lower in height than the front side of the hull.

According to an eighth aspect of the invention, in the lift change suppression structure of the boat body according to the fifth aspect, as shown in FIGS. The lift change suppression structure of the hull is characterized by alleviating blockage of the headed flow and generating a negative pressure (P _N ) on the underside of the hull.

According to a ninth aspect of the invention, in the lift force change suppression structure of the boat body according to the fifth or eighth aspect, as shown in FIGS. , and a hull lift change suppression structure characterized by comprising an inclined portion (25b) that inclines obliquely upward from the front to the rear.

The invention of claim 10 is the structure for suppressing lift change in the hull according to any one of claims 5 to 9, wherein, as shown in FIGS. The lift force change suppression structure for the hull is characterized by including rectifying portions (26A, 26B) that guide the flow.

According to an eleventh aspect of the invention, there is provided the lift change suppression structure of the boat body according to the tenth aspect, wherein the straightening section generates a negative pressure (P _N ) on the lower surface side of the boat body. This is the lift force change suppression structure.

According to a twelfth aspect of the invention, in the lift change suppression structure of the boat body according to the tenth or eleventh aspect, as shown in FIGS. The structure for suppressing lift change of the hull is characterized by having an inclined portion (26b) that inclines obliquely upward from the front to the rear.

According to a thirteenth aspect of the invention, in the lift change suppression structure for the boat body according to any one of the tenth to twelfth aspects, as shown in FIGS. The structure for suppressing lift change of the hull is characterized in that an inclined portion (26a) inclined obliquely upward from the rear to the front is provided on the lower front side of the hull.

According to a fourteenth aspect of the invention, there is provided the lift change suppression structure for a boat body according to any one of claims 1 to 13, wherein the boat body travels on a conventional line as shown in FIG. The structure for suppressing lift force change of a hull is characterized by being the hull of a current collector of a vehicle (3).

According to the present invention, it is possible to suppress a change in lift force acting on the boat body of the current collector with a simple structure.

FIG. 2 is a front view schematically showing a state in which a flow blows up toward a current collector provided with a lift change suppression structure for a boat body according to the first embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view schematically showing a current collector provided with a lift force change suppression structure for a boat body according to a first embodiment of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram of the current collector provided with the lift change suppression structure of the boat body which concerns on 1st Embodiment of this invention, (A) is a side view, (B) is a front view. 1 is a plan view schematically showing a hull provided with a hull lift change suppression structure according to a first embodiment of the present invention; FIG. 1 is a plan view schematically showing a hull provided with a hull lift change suppression structure according to a first embodiment of the present invention; FIG. 1 is a vertical cross-sectional view of a hull provided with a lift change suppression structure for a hull according to a first embodiment of the present invention; (A) is a cross-sectional view taken along line VI-VIA in FIG. B) is a cross-sectional view taken along the line VI-VIB of FIG. 5. FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram for explaining the action of the lift change suppression structure for a boat according to the first embodiment of the present invention, wherein (A) is a schematic view of a boat provided with the lift change suppression structure; FIG. 4 is a schematic diagram of a hull without a lift change suppression structure; FIG. 7 is a vertical cross-sectional view of a boat provided with a lift change suppression structure according to a second embodiment of the present invention; FIG. 11 is a plan view schematically showing a hull provided with a hull lift change suppression structure according to a third embodiment of the present invention; FIG. 11 is a plan view schematically showing a boat body provided with a lift force change suppression structure for boat body according to a fourth embodiment of the present invention; FIG. 11 is a vertical cross-sectional view of a hull provided with a hull lift change suppression structure according to a fifth embodiment of the present invention; FIG. 10A is a schematic diagram for explaining the action of the positive pressure reducing portion in the lift change suppression structure for the boat according to the fifth embodiment of the present invention, and FIG. , and (B) are schematic diagrams of a hull without a positive pressure relief portion. FIG. 12 is a vertical cross-sectional view of a boat provided with a lift change suppression structure according to a sixth embodiment of the present invention; FIG. 10A is a schematic diagram for explaining the action of the inclined portion in the lift change suppression structure for the boat according to the sixth embodiment of the present invention; 1 is a schematic diagram of a hull without an inclined portion; FIG. FIG. 12 is a vertical cross-sectional view of a hull provided with a hull lift change suppression structure according to a seventh embodiment of the present invention; FIG. 12A is a schematic diagram for explaining the action of a flow straightening section in the structure for suppressing lift change in a boat according to a seventh embodiment of the present invention; FIG. FIG. 4 is a schematic diagram of a boat without a rectifying section; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram schematically showing a wind tunnel test apparatus used in a test to confirm the effect of suppressing a change in lift by the structure for suppressing lift change in a hull according to an embodiment of the present invention; is a side view. FIG. 4 is a schematic diagram showing the definition of the wind direction in the effect confirmation test of the lift change suppression effect of the lift change suppression structure for the hull according to the embodiment of the present invention; It is the figure seen from the XVIIIB direction. FIG. 2 is an external view of a boat used in a lift change suppression effect confirmation test by a boat lift change suppression structure according to an embodiment of the present invention, and FIG. (B) is a vertical cross-sectional view of the boat body according to the first embodiment, (C) is a vertical cross-sectional view of the boat body according to the second embodiment, and (D) is a boat body according to the conventional example 1 FIG. 10 is a vertical cross-sectional view, and (E) is a vertical cross-sectional view of a hull according to Conventional Example 2; 5 is a graph showing lift force measurement results in a wind tunnel test of a boat body equipped with a lift change suppression structure according to an embodiment of the present invention; and (B) is a graph showing the lift force measurement results of boat bodies according to Example 2 and Conventional Example 2. FIG. Fig. 3 shows lift force measurement results in a wind tunnel test when the upper and lower surfaces of a boat body equipped with a lift change suppression structure according to an embodiment of the present invention are partially opened; ) to (E) are plan views of boat bodies according to Examples 2 to 4 and Conventional Example 2. FIG. Fig. 3 shows lift force measurement results in a wind tunnel test when the cross-sectional shape of a boat body equipped with a lift change suppression structure according to an embodiment of the present invention is changed, and (A) is a graph of lift force measurement results, B) is a cross-sectional view of the boat body according to the first embodiment, (C) is a cross-sectional view of the boat body according to the fifth embodiment, and (D) is a cross-sectional view of the boat body according to the first conventional example. It is a graph which shows as an example the lift force measurement result of the pantograph for conventional lines. FIG. 4 is a contour diagram showing an example of a simulation result of a flow field around a vehicle when subjected to a crosswind. 1 is a graph showing an example of lift measurement results when a conventional line pantograph receives a crosswind, (A) and (B) are schematic diagrams showing the definition of wind direction, and (C) shows the state of a wind tunnel test. It is a photograph and (D) is a graph of lift force measurement results.

(First embodiment)
A first embodiment of the present invention will be described in detail below with reference to the drawings.
An overhead contact line 1 shown in FIGS. 1 to 4 is an overhead contact line that is installed above a railroad track. The overhead wires 1 are supported at supporting points at predetermined intervals. The trolley wire 1a is an electric wire with which the current collector 6 contacts and moves. The trolley wire 1a supplies load current to the vehicle 3 as the current collector 6 slides. The track 2 is a passage (track) along which the vehicle 3 travels. The track 2 includes rails 2a for supporting and guiding the wheels 4 of the vehicle 3 to allow the vehicle 3 to travel.

A vehicle 3 shown in FIG. 1 is a railroad vehicle that runs along the track 2 . The vehicle 3 is, for example, an electric vehicle such as a train or a locomotive. The vehicle 3 is a railroad vehicle that runs on a conventional line. The vehicle 3 includes wheels 4, a vehicle body 5, a current collector 6, and the like. The wheels 4 are members that are in rolling contact with the rails 2a. Wheels 4 are rotatably held at predetermined positions of a bogie that supports vehicle body 5 and runs on track 2 . The vehicle body 5 is a structure for loading and transporting passengers or cargo. The vehicle body 5 includes a side surface 5a forming a side frame of the vehicle body 5, a roof 5b forming a roof frame of the vehicle body 5, and a shoulder portion 5c where the side surface 5a and the roof 5b intersect.

The current collector 6 shown in FIGS. 1 to 4 is a device for conducting electric power from the trolley wire 1a to the vehicle 3. As shown in FIG. The current collector 6 includes contact strips 7A and 7B shown in FIGS. 2 to 6, boat bodies (collector boats) 8A and 8B, horns 9 shown in FIGS. The boat support 10, the framework 11 shown in FIGS. 1 to 3, the main shaft 17 shown in FIGS. It is provided with an underframe 21, insulators 22, and a lift change suppression structure 23 shown in FIGS. The current collector 6 is raised when in use as shown in FIGS. 1-3 and folded when not in use. The current collector 6 shown in FIGS. 1 to 4 is a conventional line pantograph used on conventional lines. As shown in FIGS. 1 to 3, the current collector 6 is a single-arm pantograph that is asymmetrical with respect to the traveling directions D ₁ and D ₂ of the vehicle 3 and can be used in both directions. The current collector 6 is used in the bending direction in which the intermediate hinge 16 is positioned on the front side in the direction of travel, and in the anti-bending direction in which the intermediate hinge 16 is positioned on the rear side in the direction of travel. The current collector 6 shown in FIGS. 1 to 3 is moving with the vehicle 3 in the anti-yaw direction.

Contact strips 7A and 7B shown in FIGS. 2 to 6 are members that slide on the trolley wire 1a. As shown in FIGS. 2, 3B and 4, the contact strips 7A and 7B are made of metal or extend in a direction perpendicular to the traveling directions _D1 and _D2 of the vehicle 3 (in the sleeper direction). It is a plate-like member made of carbon, and as shown in FIGS. 4 and 5, it is a thin-plate-like member whose planar shape is a parallelogram. The sliders 7A, 7B are separate parts that are manufactured separately from the boat bodies 8A, 8B. mounted on top of the As shown in FIG. 4, the sliders 7A and 7B are arranged in two rows along the length direction of the boat bodies 8A and 8B with a predetermined interval in the width direction of the boat bodies 8A and 8B. The contact strip 7A is attached to the central portion of the boat bodies 8A and 8B, and is a main contact strip that slides mainly on the trolley wire 1a when the vehicle 3 is running on the main line. The sliders 7B are attached to both ends of the boat bodies 8A and 8B, and are auxiliary sliders that slide less frequently than the main sliders. The contact strips 7A and 7B, for example, in the case of metal contact strips, are formed with female threaded portions passing through the contact strips 7A and 7B. It is inserted from the boat bodies 8A, 8B side and fixed to the boat bodies 8A, 8B by this fixing member. The contact strips 7A and 7B are, for example, in the case of carbon-based contact strips, the bottoms of the contact strips 7A and 7B are held by sheaths having fixing members such as bolts on the bottom surfaces, and the securing members of the sheaths are held. are inserted into the through-holes of the boat bodies 8A and 8B, and fixed to the boat bodies 8A and 8B via the sheath portion by a fastening member such as a nut that meshes with the male threaded portion of the fixing member.

Boat bodies 8A and 8B shown in FIGS. 2 to 4 are members for supporting contact strips 7A and 7B. As shown in FIGS. 2 to 4, the boat bodies 8A and 8B are elongated metal members extending in a direction perpendicular to the trolley wire 1a (in the sleeper direction). The boat bodies 8A and 8B are arranged in parallel with each other at a predetermined interval in the forward and rearward directions of the traveling directions D ₁ and D ₂ of the vehicle 3 (the width direction of the boat bodies 8A and 8B). As shown in FIGS. 2 and 6, the boat bodies 8A and 8B are formed in a symmetrical shape (mirror image folded shape) with respect to the center line of the boat bodies 8A and 8B. As shown in FIGS. 2 to 4, when the boats 8A and 8B move in the direction of travel _D1 , the boat 8A is on the front side (upstream side) in the direction of travel, and the boat body 8B is on the rear side (downstream side) in the direction of travel. )become. On the other hand, when the boats 8A and 8B move in the direction of travel _D2 , the boat 8B is on the front side (upstream side) in the direction of travel, and the boat body 8A is on the rear side (downstream side) in the direction of travel. As shown in FIG. 6, the boat bodies 8A and 8B have a structure similar to a lip channel steel having a substantially C-shaped cross section so as to form a space inside the boat bodies 8A and 8B. be. The boat bodies 8A and 8B are formed into a predetermined shape by, for example, bending a flat metal plate. Boats 8A and 8B shown in FIGS. 2 to 4 are boats (pantograph boats for conventional lines) of current collectors 6 of vehicles 3 running on conventional lines. Both boat bodies 8A and 8B have the same structure, and include an upper portion 8a, side portions 8b and 8c, lower portions (bottom portions) 8d and 8e, a reinforcement portion 8f and the like shown in FIG. In the following description, the boat body 8A will be mainly described, and the same parts as the boat body 8A will be denoted by the same reference numerals as to the boat body 8B, and detailed description thereof will be omitted.

The upper part 8a shown in FIG. 6 is a part that constitutes the upper part of the boat body. The upper portion 8a is formed to have a flat surface so as to be in close contact with the contact strips 7A and 7B. The upper portion 8a includes an upper surface 8g on which the contact strips 7A and 7B are mounted, and a lower surface 8h opposite to the upper surface 8g. As shown in FIG. 6, the upper surface 8g includes a pair of attachment portions (strip attachment portions) 8i for attaching the contact strips 7A and 7B along the length direction of the boat bodies 8A and 8B, and a pair of contact strip attachment portions 8i shown in FIGS. A connecting portion 8j for connecting a pair of mounting portions 8i is provided at intervals in the longitudinal direction of the boat bodies 8A and 8B.

Side portions 8b and 8c shown in FIG. 6 are portions that constitute both side portions of the boat body. The side portions 8b and 8c are arranged so as to face both edges of the upper portion 8a so as to be orthogonal to the upper portion 8a. The side portion 8b is the front side portion located farther from the midpoint between the boat bodies 8A and 8B, and the side portion 8c is the rear side portion located closer to the midpoint between the boat bodies 8A and 8B. be.

The lower parts 8d and 8e are parts that constitute the lower part of the hull. The lower parts 8d, 8e are arranged at the lower edges of the sides 8b, 8c, respectively, parallel to the upper part 8a and perpendicular to the sides 8b, 8c. The lower portion 8d is the front lower portion positioned farther from the midpoint between the boats 8A and 8B, and the lower portion 8e is the rear lower portion positioned closer to the midpoint between the boats 8A and 8B.

The reinforcing portion 8f is a portion that imparts rigidity to the boat bodies 8A and 8B. The reinforcing portion 8f is formed by bending the inner edge portions of the lower portions 8d and 8e upward at a right angle, and together with the lower portions 8d and 8e, imparts bending rigidity and torsional rigidity to the boat bodies 8A and 8B.

The horn 9 shown in FIGS. 1 to 4 is a member that prevents the trolley wire 1a from entering under the boat bodies 8A and 8B. For example, when the vehicle 3 passes through a turnout, the horn 9 is connected to the trolley in a direction different from the traveling directions D ₁ and D ₂ of the vehicle 3 among the two trolley wires 1a intersecting above the turnout. This prevents the hulls 8A and 8B from interrupting the line 1a. The tip of the horn 9 protrudes from both longitudinal ends of the boat bodies 8A and 8B, and the tip is curved downward as shown in FIGS. 1 and 3B. It is a formed metal cylindrical member.

The boat support portion 10 shown in FIGS. 2 and 3 is a portion that supports the boat bodies 8A and 8B. The boat support portion 10 pushes up the boat bodies 8A and 8B horizontally with respect to the overhead wire 1, and gives the boat bodies 8A and 8B a cushioning action by a spring. The boat support portion 10 maintains the balance and smooth vertical movement of the boat bodies 8A and 8B, and improves followability to the trolley wire 1a. Boat support 10 is supported on top of framework 11 . 2 to 5, a spring 10b shown in FIG. 3, a connecting pipe 10c shown in FIGS. 3B and 4, a support portion 10d shown in FIG. It includes a spring 10e, a ceiling tube 10f shown in FIGS. 2 to 4, a connecting portion 10g shown in FIG. 3, and the like.

A support portion 10a shown in FIGS. 2 to 5 is a member that supports the boat bodies 8A and 8B via a spring 10b. As shown in FIGS. 2 and 3B, the support portions 10a are arranged below both ends of the boat bodies 8A and 8B with a gap between them. is a metal plate-shaped member (bracket) extending in a direction perpendicular to the center line of the boat bodies 8A and 8B, as shown in FIG. The support portion 10a functions as a spring receiving portion that receives the spring 10b.

A spring 10b shown in FIG. 3 is a member that elastically supports the boat bodies 8A and 8B. The spring 10b is an elastic member such as a coil spring disposed between the boat bodies 8A, 8B and the support portion 10a, and improves the ability of the contact strips 7A, 7B to follow the trolley wire 1a. The upper end of the spring 10b is attached to the lower surface 8h of the upper portion 8a of the boat bodies 8A and 8B, and the lower end of the spring 10b is attached to the upper surface of the support portion 10a.

A connecting tube 10c shown in FIGS. 3B and 4 is a member that connects the left and right horns 9. As shown in FIG. The connecting pipe 10c is arranged below the lower portions 8d and 8e between the pair of reinforcing portions 8f of the boat bodies 8A and 8B, as shown in FIG. 7, and between the support portions 10a as shown in FIG. They are arranged parallel to each other along the length direction of 8A and 8B. As shown in FIGS. 3B and 4, the connecting pipe 10c passes through the support portion 10a and both ends of the connecting pipe 10c are connected to the rear end portion of the horn 9. The connecting pipe 10c on the body 8A side, the connecting pipe 10c on the boat body 8B side, and the horn 9 constitute a connecting frame.

A support portion 10d shown in FIG. 3 is a member that supports the support portion 10a via a spring 10e. The support part 10d is arranged below the support part 10a with a gap between it and the support part 10a, and as shown in FIG. It is a plate-like member (balance) made of metal that extends in the direction. The support portion 10d functions as a spring receiving portion that receives the spring 10e. The support portion 10d is arranged parallel to the support portion 10d so that the center line of the support portion 10d is perpendicular to the center line of the ceiling pipe 10f. The support portion 10d supports the support portion 10a at both ends of the support portion 10d via springs 10e, and the central portion of the support portion 10d is rotatably supported by the ceiling pipe 10f via a hinge portion. ing.

A spring 10e shown in FIG. 3 is a member that elastically supports the support portion 10a. The spring 10e is an elastic member such as a coil spring arranged between the support portion 10a and the support portion 10d. The upper end of the spring 10e is attached to the lower surface of the support portion 10a, and the lower end of the spring 10e is attached to the upper surface of the support portion 10a.

A ceiling pipe 10f shown in FIGS. 2 to 4 is a member that rotatably supports the support portion 10d. The ceiling pipe 10f is arranged in parallel with the boat bodies 8A and 9B below the boat bodies 8A and 8B so that the center line of the ceiling pipe 10f is equidistant from the center lines of the boat bodies 8A and 8B. It is arranged perpendicular to the support portions 10a and 10d and parallel to the boat bodies 8A and 8B and the connecting pipe 10c. As shown in FIG. 3A, the ceiling pipe 10f passes through the central portion of the support portion 10d, and as shown in FIG. 11 is rotatably supported by the upper end portion of the upper frame 12 .

A connecting portion 10g shown in FIG. 3 is a portion that is rotatably connected to the balance rod 13 of the framework 11. As shown in FIG. As shown in FIG. 3A, the connecting portion 10g is formed so as to protrude downward from the central portion of the ceiling pipe 10f. As shown in FIG. 3A, the connecting portion 10g is rotatably connected to the upper end portion of the balance bar 13 through a hinge portion.

A framework 11 shown in FIGS. 1 to 3 is a member that supports the boat bodies 8A and 8B. The framework 11 has a link mechanism capable of moving vertically while supporting the boat bodies 8A and 8B, and is composed of a plurality of hinges, link members, and the like. The framework 11 includes an upper frame 12 shown in FIGS. 2 and 3, a balance bar (boat support link) 13, a lower frame 14, a balance bar 15 shown in FIG. ing. The framework 11 shown in FIGS. 2 and 3 is lifted by the biasing force of the main spring 19 when in use, and when not in use (when folded), the driving force generator 20 is generated against the biasing force of the main spring 19. It is a spring rising/air descending structure that descends by the driving force applied.

The upper frame 12 shown in FIGS. 2 and 3 is a member that supports the boat support portion 10 . The lower end of the upper frame 12 is rotatably connected to the upper end of the balance bar 15 via a hinge. The balance bar 13 is a member that maintains the boat bodies 8A and 8B and the boat support 10 in a predetermined posture. The balance bars 13 are arranged below the upper frame 12 at intervals, and always keep the postures of the boat bodies 8A and 8B and the boat support 10 horizontal when the height of the frame 11 changes. The lower end of the balance bar 13 is rotatably connected via a hinge portion to a position slightly separated from the upper end of the lower frame 14 .

The lower frame 14 is a member that is rotatably connected to the underframe 21 . The lower frame 14 is connected to the main shaft 17 at the lower end of the lower frame 14 . The balance bar 15 is a member that holds the shape of the framework 11 and moves the framework 11 up and down. The balance rods 15 are arranged at intervals under the lower frame 14, and adjust the trajectory when the hulls 8A and 8B are vertically displaced. The balance bar 15 is rotatably connected to the underframe 21 at the lower end of the balance bar 15 via a hinge. The intermediate hinge 16 is a portion that rotatably connects the upper frame 12 and the lower frame 14 . The intermediate hinge 16 functions as a joint that connects the upper frame 12 and the lower frame 14 .

The main shaft 17 is a member that moves the framework 11 up and down. The main shaft 17 operates in conjunction with the framework 11 and rotates in forward and reverse directions to move the framework 11 up and down. The main shaft 17 is rotatably supported by the underframe 21 and rotates integrally with the lower end of the lower frame 14 . The lever portions 18A and 18B are portions that convert linear motion into rotary motion. The lever portions 18A and 18B rotate integrally with the main shaft 17 with the main shaft 17 as a fulcrum.

The main spring 19 is a member that applies a lifting force to the framework 11 . The main spring 19 is a push-up spring that biases the main shaft 17 so that the main shaft 17 rotates and the framework 11 rises. One end of the main spring 19 is rotatably connected to the underframe 21 via a hinge portion, and the other end of the main spring 19 is rotatably connected to the lever portion 18A via a hinge portion. It is

The driving force generator 20 is a member that generates a driving force for rotationally driving the main shaft 17 . The driving force generator 20 is a lowering cylinder device such as a pneumatic cylinder that rotates the main shaft 17 against the biasing force of the main spring 19 when lowering the framework 11 . In the driving force generating portion 20, an action portion such as a piston rod of a lowering cylinder device that applies a driving force to the lever portion 18B is rotatably connected to the lever portion 18B via a hinge portion.

The underframe 21 shown in FIGS. 1 and 3 is a member that supports the framework 11 . The underframe 21 is installed on the roof 5 b of the vehicle body 5 via insulators 22 while supporting the base of the frame 11 . The underframe 21 supports an elevating mechanism including the main shaft 17, the levers 18A and 18B, the main spring 19, the driving force generator 20, and the like. The insulator 22 is a member that electrically insulates between the vehicle body 5 and the underframe 21 . The insulator 22 supports the bottom surface of the underframe 21 .

The lift change suppression structure 23 shown in FIGS. 4 to 6 reduces the lift acting on the boats 8A and 8B when the boats 8A and 8B receive the flow F that changes the lift acting on the boats 8A and 8B. It is a structure that suppresses change. The lift change suppression structure 23 suppresses the flow F that pushes up the hulls 8A and 8B, such as the flow F blowing up the hulls 8A and 8B and the flow F in the lateral direction with respect to the hulls 8A and 8B. When 8B receives it, the pressure change around the hulls 8A and 8B is relieved, and the lift force of the hulls 8A and 8B is stabilized. The lift change suppression structure 23 has openings 24A and 24B. Below, the openings 24A and 24B shown in FIGS. 4, 5, 9 and 10 are colored to facilitate understanding of the invention.

The openings 24A and 24B shown in FIGS. 4 to 6 are portions that pass through the boat bodies 8A and 8B in the vertical direction and are opened on the upper and lower surfaces of the boat bodies 8A and 8B. The openings 24A and 24B change the flow field around the boat bodies 8A and 8B by allowing the flow F from below to upward to pass through the lower surface side (bottom side) of the boat bodies 8A and 8B, thereby changing the flow field around the boat bodies 8A and 8B. , 8B. The openings 24A and 24B relieve the positive pressure _PP generated on the lower surface side of the boat bodies 8A and 8B by relieving blockage of the flow F directed upward from below on the lower surface sides of the boat bodies 8A and 8B. Acts as a buffer. The openings 24A and 24B have the same structure, and as shown in FIG. 4, the opening 24A is formed in the boat 8A and the opening 24B is formed in the boat 8B.

As shown in FIGS. 4 and 5, the openings 24A and 24B are formed between adjacent connecting portions 8j, and are formed substantially continuously between one end and the other end of the boat bodies 8A and 8B. It is The openings 24A, 24B are through-holes having a square planar shape, and are provided with left and right contact strips 7A, 7B along the length direction of the boat bodies 8A, 8B so as to penetrate the upper parts 8a of the boat bodies 8A, 8B. formed between. As shown in FIG. 5, the openings 24A and 24B are formed narrower at the central portions of the boat bodies 8A and 8B supporting the contact strip 7A and support the contact strip 7B. The openings 24A, 24B at both ends of the boat bodies 8A, 8B are formed wide. As shown in FIG. 6A, the openings 24A and 24B are formed on the side of the lower surface 8h of the upper portion 8a and into which the flow F flows, and the opening 24a is formed on the side of the upper surface 8g of the upper portion 8a to allow the flow F to flow. An outflow port 24b, and a channel 24c through which the flow F flows from the inflow port 24a to the outflow port 24b are provided. The openings 24A and 24B are formed so that the inflow port 24a and the outflow port 24b have the same shape, and the center line of the channel 24c is perpendicular to the upper surface 8g and the lower surface 8h of the upper portion 8a. there is

Next, the operation of the structure for suppressing change in lift force of the hull according to the first embodiment of the present invention will be described.
In the following, as shown in FIGS. 1 to 3 and 7, the case where the vehicle 3 travels in the traveling direction D ₁ will be mainly described. Here, boat bodies 8A and 8B shown in FIG. 7(A) are boat bodies according to the first embodiment provided with a lift change suppression structure 23. As shown in FIG. Boats 108A and 108B shown in FIG. 7(B) are conventional boats that do not include lift change suppression structure 23. Boats 108A and 108B shown in FIG. Below, with respect to the boat bodies 108A and 108B shown in FIG. 7B, the parts corresponding to the boat bodies 8A and 8B shown in FIG.

As shown in FIG. 1, when the vehicle 3 is running on the track 2 in the traveling direction _D1 , the boat body 8A of the current collector 6 receives the wind from the front side in the traveling direction, and the vehicle 3 receives the side wind. A side wind is blown up by the shoulder portion 5c of the vehicle body 5, and the boat body 8A is blown up obliquely from below. For example, when the vehicle 3 is traveling in the traveling direction _D1 on the railroad 2 on an embankment or a viaduct, if the vehicle 3 receives a crosswind due to the terrain conditions and weather conditions along the railway, the shoulder of the vehicle body 5 A crosswind is blown up at 5c. As a result, the boat body 8A receives the flow F from the lateral direction and obliquely downward.

As shown in FIG. 7(B), when the boat body 108A does not have the opening 24A, when the lower parts 108d and 108e of the boat body 108A receive the flow F, the flow F is generated on the lower surface side of the boat body 108A. As the water stagnates, the positive pressure _PP on the lower surface side of the boat body 108A increases. In addition, since the flow F separates at the upper corner portion on the front side of the traveling direction of the contact strip 107A, a vortex is generated behind the contact strip 107A, and the negative pressure _PN at the upper portion of the contact strip 107A increases. As a result, positive pressure P _P is applied to the lower surface of boat 108A, and negative pressure P _N is applied to the upper surface of contact strip 107A, thereby increasing the positive lift that raises boat 108A.

On the other hand, as shown in FIG. 7A, when the boat body 8A has an opening 24A, the flow F directed toward the lower parts 8d and 8e of the boat body 8A passes through the gap between the pair of reinforcing parts 8f. Then, the flow F flows in from the inlet 24a of the opening 24A and flows out from the outlet 24b. Therefore, as shown in FIG. 7(A), the flow F smoothly flows from below to above the boat body 8A without stagnation, and as shown in _FIG. is suppressed from increasing. Further, as shown in FIG. 7(A), the direction of the flow F separated at the upper corners of the contact strips 7A and 7B on the front side in the traveling direction is changed by the flow F flowing out from the outflow port 24b, and the direction of the flow F is changed. , 7B is suppressed. Therefore, the flow field around the hull 8A changes as the flow F exits from the lower side to the upper side of the hull 8A. As a result, the positive pressure _PP on the bottom side of the boat body 8A is suppressed from increasing, and the negative pressure _PN on the top side of the contact strips 7A and 7B is also suppressed from increasing. A change in pressure in the surrounding area is alleviated, and an increase in positive lift that raises the hull 8A is suppressed. Further, by providing the opening 24A penetrating the upper and lower surfaces of the boat body 8A, the pressure-receiving area of the boat body 8A that receives the positive pressure P _P and the negative pressure P _N is reduced, and the change in lift caused by crosswinds is reduced. Even when the vehicle 3 travels in the traveling direction D ₂ opposite to the traveling direction D ₁ , the opening 24B on the side of the boat 8B functions in the same manner as the opening 24A on the side of the boat 8A.

As shown in FIG. 1, when the hull 8A moving in the direction of travel D ₁ receives only an opposing wind from the front side in the direction of travel, the inclination angle (angle of attack) of the hull 8A with respect to the flow F, or the angle from the hull 8A In some cases, the wind direction angle in the pitch direction of the viewed flow F becomes larger than a predetermined angle, and the pressure difference between the upper surface side of the boat body 8A and the lower surface side of the boat body 8A becomes larger than a predetermined value. In this case, since the flow F passes through the opening 24A between the upper surface side and the lower surface side of the boat 8A, the pressure difference therebetween is reduced. As a result, an increase in positive lift that raises the hull 8A and an increase in negative lift that lowers the hull 8A are suppressed, and changes in lift are mitigated.

The lift change suppression structure for a boat body according to the first embodiment of the present invention has the following effects.
(1) In the first embodiment, the openings 24A and 24B penetrate the boat bodies 8A and 8B in the vertical direction, and open at the upper surface 8g and the lower surface 8h of the boat bodies 8A and 8B. Therefore, by opening the upper and lower surfaces of the boat bodies 8A and 8B, it is possible to suppress the change in lift when the current collector 6 receives a crosswind or a counterwind. Further, the lift characteristics when the vehicle 3 is traveling normally are not greatly affected, and the lift can be prevented from greatly changing when subjected to a crosswind. As a result, the pressure rise on the lower surface side of the boat body 8A is suppressed, and the negative pressure P _N on the upper surface side of the boat body 8A is also alleviated, so that the lift acting on the boat bodies 8A and 8B can be stabilized. . Furthermore, when the pressure difference between the upper surface side and the lower surface side of the hull 8A increases due to the current collector 6 receiving an opposing wind, the pressure difference between them can be alleviated, and the lift fluctuation can be reduced. can be suppressed.

(2) In the first embodiment, the openings 24A, 24B are formed substantially continuously between one end and the other end of the boat bodies 8A, 8B. Therefore, by opening the upper and lower surfaces of the boats 8A and 8B substantially fully open, the openings 24A and 24B provide pressure receiving areas for receiving the positive pressure P _P and the negative pressure P _N that increase the lift of the boats 8A and 8B. can be reduced, and lift changes due to crosswinds and oncoming winds can be mitigated.

(3) In the first embodiment, the hulls 8A and 8B of the current collector 6 of the vehicle 3 running on the conventional line. Therefore, it is possible to effectively reduce the change in lift when the conventional line pantograph receives crosswinds or counterwinds. In addition, the lift force of the pantograph hull for conventional lines, which has a lower running speed than the Shinkansen and a large angle of inclination (angle of attack) of the hulls 8A and 8B with respect to the uniform flow F, can be stabilized.

(Second embodiment)
In the following description, the same parts as those shown in FIGS. 1 to 7 are denoted by the same reference numerals, and detailed description thereof will be omitted.
Unlike the boat bodies 8A and 8B shown in FIG. 6, the boat bodies 8A and 8B shown in FIG. A pair of lower portions 8d and 8e and a pair of reinforcing portions 8f shown in 6 are omitted. As shown in FIG. 8, the boat bodies 8A and 8B have a structure similar to channel steel having a substantially U-shaped (U-shaped) cross section. The boats 8A, 8B are formed in a shape symmetrical in the front-rear direction (mirror-image folded shape) with respect to the center line of the boats 8A, 8B. This second embodiment has the same effect as the first embodiment.

(Third embodiment)
Unlike the openings 24A and 24B shown in FIG. 5, the openings 24A and 24B shown in FIG. 9 are formed in the central portions of the boat bodies 8A and 8B. As shown in FIG. 9, the openings 24A and 24B are formed by partially opening the upper parts 8a of the boat bodies 8A and 8B so that they are opened only at the center of the upper parts 8a of the boat bodies 8A and 8B. This third embodiment has the same effects as those of the first and second embodiments.

(Fourth embodiment)
Unlike the openings 24A and 24B shown in FIGS. 5 and 9, the openings 24A and 24B shown in FIG. 10 are formed at one end and the other end of the boat bodies 8A and 8B. As shown in FIG. 10, the openings 24A and 24B are formed by partially opening the upper parts 8a of the boat bodies 8A and 8B so that they are opened only at the ends of the upper parts 8a of the boat bodies 8A and 8B. . This fourth embodiment has the same effects as those of the first to third embodiments.

(Fifth embodiment)
The lift change suppression structure 23 includes openings 24A and 24B, positive pressure relief portions 25A and 25B, and the like. The positive pressure relief portions 25A, 25B are portions that relieve the positive pressure _PP generated on the lower surface sides of the boat bodies 8A, 8B. As shown in FIG. 12(A), the positive pressure relief sections 25A and 25B relieve the blockage of the flow F directed upward from below on the lower surface side of the boat bodies 8A and 8B, thereby allowing the flow F to flow without stagnation. The positive pressure _PP generated on the lower surface side of the bodies 8A and 8B is relieved. As shown in FIG. 12, the positive pressure relief portions 25A and 25B are designed to increase the positive pressure on the lower surface side of the boat bodies 8A and 8B when the boat bodies 8A and 8B receive the flow F that pushes up the boat bodies 8A and 8B. By alleviating P _P , an increase in the positive lift acting on the hulls 8A and 8B is suppressed. The positive pressure relieving portions 25A and 25B have lower portions 25a shown in FIGS.

A lower portion 25a shown in FIGS. 11 and 12 is a portion lower in height than the front sides of the boat bodies 8A and 8B. The lower portion 25a functions as a blockage relieving portion that relieves blockage of the flow F directed upward from below on the lower surface sides of the boat bodies 8A and 8B. As shown in FIG. 12(A), the lower portion 25a is positioned at an intermediate position between the boat bodies 8A and 8B, considering that the boat bodies 8A and 8B move in both directions of travel _D1 and _D2 . They are arranged on the boat bodies 8A and 8B so as to form a symmetrical shape (mirror-image folded shape) about a point. As shown in FIG. 12, the lower portion 25a is constructed so that the gap between the lower portion 25a and the ceiling pipe 10e is widened so that the flow F flows without stagnation. The height H ₂ of the rear sides of boats 8A and 8B is formed lower than the height H ₁ of the front sides of 8B. For example, the lower portion 25a is manufactured from the beginning by separating the rear side portion 8c of the hulls 8A and 8B shown in FIG. formed by

Next, the action of the positive pressure reducing portion in the structure for suppressing change in lift force for the hull according to the fifth embodiment of the present invention will be described.
As shown in FIG. 12(B), when the boat body 108A does not have the positive pressure relief portion 25A, the gap between the boat body 108A and the ceiling pipe 110f is narrow, so the lower surface side of the boat body 108A It becomes difficult for the flow F from the bottom to the top to pass between the boat body 108A and the ceiling pipe 110f. Therefore, when the lower surface of the boat body 108A receives the flow F, the flow F becomes stagnant on the lower surface side of the boat body 108A, and the positive pressure _PP generated on the lower surface side of the boat body 108A increases. of lift increases.

On the other hand, as shown in FIG. 12A, when the boat body 8A is provided with the positive pressure relief portion 25A, the gap between the boat body 8A and the ceiling pipe 10e is widened. Therefore, the flow F directed toward the lower surface of the boat body 8A passes between the lower portion 25a and the ceiling pipe 10e, and the flow F passes through the gap between the boat body 8A and the boat body 8B. , 8B from below to above without stagnation. Also, the flow F directed toward the lower surface of the boat body 8A enters from the inlet 24a of the opening 24A and flows out from the outlet 24b. As a result, the flow field around the boat 8A changes, suppressing the rise of the positive pressure _PP generated on the lower surface side of the boat 8A, thereby mitigating the pressure change in the boat 8A and raising the boat 8A. An increase in positive lift is suppressed. Even when the vehicle 3 travels in the direction of travel D ₂ opposite to the direction of travel D ₁ , the positive pressure relief portion 25B on the boat body 8B side shown in FIG. It functions similarly to 25A.

In addition to the effects of the first to fourth embodiments, the lift force change suppression structure for a boat according to the fifth embodiment of the present invention has the following effects.
(1) In the fifth embodiment, the positive pressure relief portions 25A and 25B relieve the positive pressure _PP generated on the lower surface side of the boat bodies 8A and 8B. Therefore, when the boat bodies 8A and 8B receive the blowing-up flow F, it is possible to suppress an increase in the positive pressure _PP generated on the lower surface side of the boat bodies 8A and 8B. As a result, the pressure increase on the lower surface side of the boat body 8A is suppressed, and it is possible to suppress the change in the lift acting on the boat bodies 8A and 8B.

(2) In the fifth embodiment, the positive pressure relief portions 25A and 25B relieve blockage of the flow F directed upward from the bottom side of the boat bodies 8A and 8B. Therefore, when the hulls 8A and 8B receive the blowing-up flow F, the flow F can pass smoothly between the hulls 8A and 8B and the ceiling pipe 10e. As a result, it is possible to suppress an increase in the positive pressure _PP generated on the lower surface side of the boat bodies 8A, 8B, thereby suppressing an increase in the positive lift acting on the boat bodies 8A, 8B.

(3) In the fifth embodiment, the rear side of the boat bodies 8A, 8B is provided with a lower portion 25a whose height is lower than that of the front sides of the boat bodies 8A, 8B. Therefore, by making the rear height H2 of the boat bodies _8A and 8B lower than the height _H1 of the front sides of the boat bodies 8A and 8B, the positive lift that raises the boat bodies 8A and 8B can be increased. can be easily suppressed. For example, an increase in positive lift force can be easily suppressed simply by removing the rear side portion 8c of the boat body 8A, 8B from the upper portion 8a. In addition, by changing the shape of the boats 8A and 8B in the inner region between the boats 8A and 8B, the positive pressure generated on the lower surface side of the boats 8A and 8B due to the blockage of the flow F when subjected to a crosswind. _PP can be relaxed.

(Sixth embodiment)
The positive pressure relief portions 25A and 25B are portions that relieve blockage of the upward flow F on the lower surface side of the boat bodies 8A and 8B and generate a negative pressure P _N on the lower surface side of the boat bodies 8A and 8B. be. As shown in FIG. 14A, the positive pressure relief portions 25A and 25B create a negative pressure P _N on the lower surface side of the boat bodies 8A and 8B, thereby reducing the positive pressure P _P on the lower surface sides of the boat bodies 8A and 8B. is relaxed, and a negative lift is applied to the hulls 8A and 8B. As shown in FIGS. 13 and 14A, the positive pressure relief portions 25A and 25B are prismatic members having a substantially triangular cross section, and are arranged along the longitudinal direction of the boat bodies 8A and 8B. . As shown in FIG. 14A, the positive pressure relief portions 25A and 25B are attached to the lower surfaces 8h on the rear sides of the upper portions 8a of the boat bodies 8A and 8B. The positive pressure relief portions 25A and 25B are attached to the upper portions 8a of the boat bodies 8A and 8B, for example, after the rear side portions 8c of the boat bodies 8A and 8B shown in FIG. 6 are removed from the upper portions 8a. The positive pressure relief portions 25A and 25B include an inclined portion 25b, a joint portion 25c, side portions 25d and 25e, a lower portion 25f, and the like shown in FIG.

The slant portion 25b shown in FIG. 13 is a portion that slants obliquely upward from the front to the rear on the rear side of the hulls 8A and 8B. The inclined portion 25b functions as a block relief portion that relieves blockage of the flow F directed upward from below on the lower surface side of the boat bodies 8A and 8B, and generates a negative pressure P _N on the lower surface side of the boat bodies 8A and 8B. It also functions as a negative pressure generator. As shown in FIG. 14(A), the slant portion 25b is formed at an intermediate position between the boat bodies 8A and 8B, considering that the boat bodies 8A and 8B move in both directions of travel _D1 and _D2 . They are formed in a symmetrical shape (mirror-image folded shape) with respect to a point, and are arranged on the boat bodies 8A and 8B, respectively. As shown in FIG. 14(A), the inclined portion 25b is arranged so as to widen the gap between the inclined portion 25b and the ceiling pipe 10e so that the flow F flows smoothly between them, as shown in FIG. 6(A). 1 is chamfered at the lower corners on the downstream side where the side portions 8c and the lower portions 8e of the boat bodies 8A and 8B intersect. The inclined portion 25b is formed as a flat inclined surface inclined at a predetermined angle as shown in FIG.

A joint portion 25c shown in FIG. 13 is a portion that is joined to the lower surface 8h of the upper portion 8a and is formed on a flat surface. The side portion 25d is a portion that constitutes the side surfaces of the positive pressure relief portions 25A and 25B, and is formed on a flat surface. The side portion 25e is a portion that constitutes the side surfaces of the positive pressure relief portions 25A and 25B, faces the reinforcing portion 8f, and is formed on a flat surface parallel to the side portion 25d. The lower portion 25f is a portion formed at the same height as the lower portion 8d, and is formed on a flat surface parallel to the joint portion 25c.

Next, the operation of the inclined portion in the lift force change suppression structure for a boat body according to the sixth embodiment of the present invention will be described.
As shown in FIG. 14(B), when the boat body 108A does not have the inclined portion 25b, the gap between the boat body 108A and the ceiling pipe 110f is narrow, so that the flow F directed toward the bottom surface of the boat body 108A It becomes difficult to pass between the hull 108A and the ceiling tube 110f. Therefore, when the lower surface of the boat body 108A receives the flow F, the flow F becomes stagnant on the lower surface of the boat body 108A, the positive pressure PP generated on the lower surface side of the boat body 108A increases, and the positive pressure _PP that raises the boat body 108A rises. Increases lift. In addition, the flow F that flows upward on the lower surface side of the boat body 108A collides directly with the lower surface of the boat body 108A, and the pressure receiving area that receives the flow F that bounces up the boat body 108A increases. The positive pressure _PP generated on the side increases.

On the other hand, as shown in FIG. 14A, when the boat body 8A is provided with the sloped portion 25b, the gap between the sloped portion 25b and the ceiling pipe 10e is widened, and the pressure is directed toward the lower surface of the boat body 8A. The flow F passes between the inclined portion 25b and the ceiling pipe 10e, and passes through the gap between the boat body 8A and the boat body 8B. Therefore, the flow F flows smoothly from the bottom to the top between the boat bodies 8A and 8B, and the flow F flows along the inclined portion 25b, thereby accelerating the flow F and changing the flow field around the boat body 8A. do. As a result, the inclined portion 25b becomes a negative pressure P _N to generate a negative lift force in the boat bodies 8A and 8B, suppressing the pressure increase on the lower surface side of the boat body 8A and mitigating the pressure change in the boat body 8A. , the increase in the positive lift that raises the hull 8A is suppressed. Further, since the lower part 8e of the boat body 8A is chamfered by the inclined part 25b, the area where the flow F directed toward the lower surface of the boat body 8A directly collides with the lower surface of the boat body 8A is reduced. Therefore, the pressure-receiving area that receives the flow F that bounces the boat 8A becomes smaller, and the positive pressure _PP generated on the lower surface side of the boat 8A becomes smaller. Furthermore, the flow toward the lower surface of the boat body 8A flows in from the inlet 24a of the opening 24A, and the flow F flows out from the outlet 24b. As a result, an increase in pressure on the lower surface side of the boat 8A is suppressed, pressure changes in the boat 8A are moderated, and an increase in the positive lift that raises the boat 8A is suppressed. Even when the vehicle 3 travels in the direction of travel D ₂ opposite to the direction of travel D ₁ , the inclined portion 25b on the boat body 8B side shown in FIG. Function.

In addition to the effects of the first to fifth embodiments, the structure for suppressing lift force change of the hull according to the sixth embodiment of the present invention has the following effects.
(1) In the sixth embodiment, the positive pressure relief portions 25A and 25B relieve the blockage of the flow F directed upward from the bottom side of the boat bodies 8A and 8B, and The negative pressure P _N is generated by the positive pressure relieving portions 25A and 25B. Therefore, when the hulls 8A and 8B receive the blowing-up flow F, it is possible to suppress the increase in the positive pressure _PP generated on the lower surface side of the hulls 8A and 8B. The acting positive lift can be suppressed. In addition, it is possible to prevent a large change in lift during normal running without crosswinds.

(2) In the sixth embodiment, on the rear side of the hulls 8A and 8B, the inclined portion 25b is inclined obliquely upward from the front to the rear. Therefore, by changing the shape of the portion located between the two boat bodies 8A and 8B, the flow F flows smoothly between the boat bodies 8A and 8B, and the lift acting on the boat bodies 8A and 8B. increase can be suppressed. For example, by changing the shape of the hulls 8A and 8B in the inner region between the hulls 8A and 8B, the positive pressure generated on the lower surface side of the hulls 8A and 8B due to the blockage of the flow F when subjected to a crosswind. _PP can be relaxed. Further, the flow F is accelerated by the inclined portion 25b, a negative pressure P _N can be created in the inclined portion 25b, and a negative lift force can be produced in the hulls 8A and 8B.

(Seventh embodiment)
The lift change suppression structure 23 shown in FIGS. 15 and 16 includes positive pressure reducing sections 25A and 25B, rectifying sections 26A and 26B, and the like. The rectifying portions 26A, 26B are portions that guide the flow F toward the positive pressure relieving portions 25A, 25B. As shown in FIG. 16, the rectifying sections 26A, 26B suppress an increase in the lift of the boats 8A, 8B by generating negative lift in the boats 8A, 8B. As shown in FIG. 16(A), the rectifying sections 26A and 26B are arranged between the boat bodies 8A and 8B considering that the boat bodies 8A and 8B move in both directions of travel _D1 and _D2 . are arranged on the boat bodies 8A and 8B so as to form a symmetrical shape (a mirror image folded shape) centering on the midpoint of the . As shown in FIGS. 13 and 14A, the rectifying portions 26A and 26B are prismatic members having a substantially triangular cross-sectional shape. It is arranged along the length direction of 8A and 8B. As shown in FIG. 14(A), the straightening sections 26A and 26B are attached to the front lower portions 8d of the boat bodies 8A and 8B. The rectifying portions 26A and 26B include inclined portions 26a and 26b and mounting portions 26c shown in FIG.

The inclined portion 26a shown in FIG. 15 is a portion of the front lower portion 8d of the boat body 8A, 8B, which is inclined obliquely upward from the rear to the front. As shown in FIG. 16A, the inclined portion 26a functions as a negative pressure generating portion that imparts a curvature to the flow F directed toward the lower portion 8d of the hulls 8A and 8B to generate a negative pressure P _N in the inclined portion 26b. do. The inclined portion 26a is formed into a flat inclined surface as shown in FIG.

The inclined portion 26b is a portion of the front lower portion 8d of the boat body 8A, 8B, which is inclined obliquely upward from the front to the rear. The inclined portion 26b functions as a negative pressure generating portion that generates a negative pressure P _N in the inclined portions 25b of the positive pressure relaxation portions 25A and 25B. The inclined portion 26b is formed on a flat inclined surface like the inclined portion 26a, and generates a negative pressure P _N in the inclined portion 26b on the downstream side. The lower end of the inclined portion 26b is connected to the lower end of the inclined portion 26a. The attachment portion 26c is a portion attached to the lower portion 8d and is formed on a flat surface.

Next, the action of the rectifying section in the structure for suppressing lift change in the boat body according to the seventh embodiment of the present invention will be described.
As shown in FIG. 16A, when the boat body 8A is provided with a rectifying portion 26A, the flow F directed toward the lower portion 8d of the boat body 8A is given a curvature by the inclined portion 26a and flows along the inclined portion 26b. As a result, the flow F accelerates and the flow field around the hull 8A changes. As a result, the inclined portion 26b becomes a negative pressure P _N to generate a negative lift force on the boat bodies 8A and 8B, suppressing the pressure increase on the lower surface side of the boat body 8A and mitigating the pressure change in the boat body 8A. , and an increase in the positive lift of the hull 8A is suppressed. Further, the flow F flowing along the inclined portion 26b is guided toward the inclined portion 25b, passes between the inclined portion 25b and the ceiling pipe 10e, and flows between the boat body 8A and the boat body 8B. A flow F passes through the gap. Therefore, the flow F flows smoothly from the bottom to the top between the boat bodies 8A and 8B, and the flow F flows along the inclined portion 25b, thereby accelerating the flow F and changing the flow field around the boat body 8A. do. As a result, the inclined portion 25b becomes a negative pressure P _N to generate a negative lift force on the boat bodies 8A and 8B, suppressing the pressure rise in the lower part 8d of the boat body 8A and mitigating the pressure change in the boat body 8A. , the increase in the positive lift that raises the hull 8A is suppressed.

Further, since the lower portion 8e of the boat body 8A is chamfered by the inclined portion 25b, the area where the flow F directly collides with the lower portion 8e of the boat body 8A is reduced, and the pressure receiving area that receives the flow F that bounces up the boat body 8A is small. As a result, the positive pressure _PP generated on the lower surface side of the boat body 8A becomes smaller. Further, the flow F directed toward the lower surface of the boat body 8A flows along the inclined portion 26b, so that the flow F flows in from the inlet 24a of the opening 24A and flows out from the outlet 24b. As a result, an increase in the positive lift force of the boat body 8A is suppressed, pressure changes in the boat body 8A are moderated, and an increase in the positive lift force that raises the boat body 8A is suppressed. Even when the vehicle 3 moves in the direction of travel D ₂ opposite to the direction of travel D ₁ , the straightening portion 26B on the side of the boat 8B shown in FIG. Function.

In addition to the effects of the first to sixth embodiments, the lift force change suppression structure for a boat according to the seventh embodiment of the present invention has the following effects.
(1) In the seventh embodiment, the rectifying sections 26A and 26B guide the flow F toward the positive pressure reducing sections 25A and 25B. Therefore, the positive pressure _PP generated on the lower surface side of the boat bodies 8A, 8B can be alleviated, and the change in the lift acting on the boat bodies 8A, 8B can be suppressed.

(2) In the seventh embodiment, the rectifying sections 26A and 26B generate the negative pressure _PN on the lower surface sides of the boat bodies 8A and 8B. Therefore, when the hulls 8A and 8B receive the blowing flow F, a negative lift force can be applied to the hulls 8A and 8B. As a result, it is possible to suppress an increase in the positive lift acting on the hulls 8A and 8B. In addition, it is possible to prevent a large change in lift during normal running without crosswinds.

(3) In the seventh embodiment, the inclined portion 26b is inclined obliquely upward from the front to the rear at the front lower portions 8d of the boat bodies 8A and 8B. Therefore, by changing the shape of the portion located between the two boat bodies 8A and 8B, the flow F can be accelerated by the inclined portion 26b, and a negative pressure P _N can be created in the inclined portion 26b. A negative lift force can be created on the bodies 8A, 8B.

(4) In the seventh embodiment, the inclined portion 26a inclines obliquely upward from the rear toward the front at the lower portion 8d on the front side of the boat bodies 8A and 8B. Therefore, by changing the shape of the portion located between the two boat bodies 8A and 8B, it is possible to give a curvature to the flow F by the inclined portion 26a and create a negative pressure P _N in the inclined portion 26b on the downstream side. can create a negative lift force on the hulls 8A and 8B.

Next, an embodiment of the invention will be described.
(Effect confirmation test for suppressing lift change)
A wind tunnel test apparatus shown in FIG. 17 was used to evaluate the effect of suppressing changes in lift when the top and bottom surfaces of the hulls shown in FIGS. 4 to 16 were opened. A large-scale, open-body, low-noise wind tunnel test facility of the Railway Technical Research Institute was used to confirm the effect of suppressing changes in lift force. As shown in FIG. 17, an actual pantograph for a conventional line was placed on the turntable of the second model support carriage in the wind tunnel measurement section of the large-scale low-noise wind tunnel test apparatus, facing the anti-winding direction. After setting the roll angle by lifting one side of the pantograph base, the turntable was rotated to set the yaw angle, air was blown out from the blowing nozzle to the pantograph in the wind tunnel measurement section, and the lift acting on the hull was measured. . In the lift change suppression effect confirmation test, the wind speed in each direction when viewed from the pantograph was defined as shown in FIG. The yaw angle θ was 0° in the anti-swinging direction and 180° in the swinging direction, and within the range of this yaw angle θ, the roll angle φ was set in the direction in which the flow rose with respect to the pantograph.

In a test to confirm the effect of suppressing changes in lift force, the springs that support the hull and connecting frame were replaced with spacers to fix vertical displacement, and a load cell (LUR- N-500NSA1 (capacity 500N)) was installed, and the top of the upper frame (the part that receives the key of the key device) and the load cell were connected with a wire. For lift measurement, the increment of load cell output when there is no wind is detected as lift, 500N=4V output, 200Hz low-pass filtered waveform is sampled at 500Hz, and recorded for about 30 seconds at each wind speed stage. A time average value was calculated.

(specimen)
The specimen is a general single-arm type pantograph for conventional lines as shown in FIGS. It is Examples 1 and 2 shown in FIGS. 19(A) to (C) and FIG. 21(B) are boat bodies 8A and 8B of the first embodiment shown in FIG. 6 and the second embodiment shown in FIG. An opening is formed substantially continuously between one end and the other end of the hull. As shown in FIGS. 19B and 19C, Examples 1 and 2 have two different cross-sectional shapes. Example 1 shown in FIG. 19B has a substantially C-shaped bending type cross-sectional shape, like the first embodiment shown in FIG. Example 2 shown in FIGS. 19C and 21B has a substantially U-shaped U-shaped cross-sectional shape, like the second embodiment shown in FIG.

Examples 3 and 4 shown in FIGS. 21(C) and 21(D) each have a substantially U-shaped U-shaped cross-sectional shape, similar to Example 2 shown in FIG. 19(C). Example 3 shown in FIG. 21(C) is boat bodies 8A and 8B of the third embodiment shown in FIG. 9, and an opening is formed only in the center of the boat body. Example 4 shown in FIG. 21(D) is boat bodies 8A and 8B of the fourth embodiment shown in FIG. 10, and openings are formed only at the ends of the boat bodies.

Embodiment 5 shown in FIG. 22(C) has an improved cross-sectional shape of the substantially C-shaped bending type boat body of Embodiment 1 shown in FIG. 19(B). Example 5 shown in FIG. 22(C) is boat bodies 8A and 8B of the fifth embodiment shown in FIG. 8a has been removed.

Conventional examples 1 and 2 shown in FIGS. 19(D) and 19(E) close the openings of the hulls of Examples 1 and 2 shown in FIGS. 19(B) and 19(C). Similar to Examples 1 and 2, Conventional Examples 1 and 2 have two different cross-sectional shapes, as shown in FIGS. Conventional example 1 shown in FIG. 19(D) has a substantially C-shaped folded cross-sectional shape similar to the first embodiment shown in FIG. Conventional example 2 shown in FIG. 19(E) has a substantially U-shaped U-shaped cross-sectional shape similar to the second embodiment shown in FIG.

(Lift force change suppression effect due to the upper and lower surface openings of the hull)
We compared lift forces with and without openings on the upper and lower surfaces of the hull. The graph shown in FIG. 20 is the lift force measurement result with and without an opening when a wind tunnel test was conducted under the measurement conditions of a test wind speed of 30 m/s (108 km/h) and a roll angle of 15°. The vertical axis is the lift force (N), and the horizontal axis is the yaw angle θ (deg). As shown in FIG. 20, it was confirmed that opening the top and bottom surfaces of the hull in both the cross-sectional shapes of Examples 1 and 2 can suppress the increase in lift over a wider yaw angle range than in Conventional Examples 1 and 2. was done. In particular, it was confirmed that a large lift force change suppression effect can be obtained in the yaw angle ranges of 42° to 56° and 124° to 138°, where the lift is at its maximum value. Further, when comparing Examples 1 and 2 with Conventional Examples 1 and 2, the lift force in the bowing direction (yaw angle of 180°) and in the anti-bowing direction (yaw angle of 0°) is greater depending on the presence or absence of openings on the upper and lower surfaces of the hull. has not changed. For this reason, it was confirmed that Examples 1 and 2, like Conventional Examples 1 and 2, did not affect lift during normal running.

(Effect of suppressing lift change by partial opening on the upper and lower surfaces of the hull)
A comparison was made of the lift force due to partial openings on the upper and lower surfaces of the hull. The graph shown in FIG. 21(A) is the lift force measurement result when a wind tunnel test was conducted under the measurement conditions of a test wind speed of 30 m/s (108 km/h) and a roll angle of 15°. The vertical axis is the lift force (N), and the horizontal axis is the yaw angle θ (deg). As shown in FIG. 21A, when the upper and lower surfaces of the boat body are partially opened like the boat bodies according to the third and fourth embodiments, the upper and lower surfaces of the boat body are opened like the boat body according to the second embodiment. Although the effect of suppressing the increase in lift is small compared to the case where all the openings are open, it was confirmed that a certain effect of suppressing changes in lift was obtained.

(Effect of suppressing change in lift by changing the cross-sectional shape of the hull)
We compared the lift force by changing the cross-sectional shape of the hull. The graph shown in FIG. 22(A) is the lift force measurement result when the wind tunnel test was conducted under the measurement conditions where the test wind speed (km/h) was varied at a roll angle of 15° and a yaw angle of 56°. The vertical axis is lift (N) and the horizontal axis is wind speed (km/h). As shown in FIG. 22(A), when there is a top opening like in Example 5, and when the cross-sectional shape is obtained by removing downstream parts, the top opening like in Example 1 is formed. Although the effect of suppressing the increase in lift is small compared to the other case, it was confirmed that a certain effect of suppressing the change in lift was obtained due to the effect of the flow blockage being reduced and the effect of blowing through.

(Other embodiments)
The present invention is not limited to the embodiments described above, and various modifications and changes are possible as described below, which are also within the scope of the present invention.
(1) In this embodiment, the case where the current collector 6 is a conventional line pantograph has been described as an example, but the present invention can also be applied to the case where the current collector 6 is a Shinkansen pantograph. can be done. Further, in this embodiment, the case where the current collector 6 is a single-arm pantograph has been described as an example, but the case where the current collector 6 is a pantograph of another type such as a diamond-shaped pantograph is also applicable. The invention can be applied. Furthermore, in this embodiment, the current collector 6 that can be used in both the bowing direction and the anti-winding direction has been described as an example, but the collector that can be used only in either the bowing direction or the anti-winding direction is described. The present invention can also be applied to electronic devices.

(2) In this embodiment, the current collector 6 having a spring-up/air-down structure was described as an example, but the present invention is not limited to the current collector 6 having such a structure. For example, the present invention can be applied to a current collector having an air rise/spring fall type structure in which the frame 11 is lifted by the driving force generator 20 when in use, and the frame 11 is lowered by the main spring 19 when folded. . Further, in this embodiment, the current collector 6 having a structure in which the upper end of the balance rod 13 is rotatably connected to the connecting portion 10g via the hinge portion has been described as an example. The present invention can also be applied to a current collector having a structure in which the upper ends of the balance rods 13 are rotatably connected to the ceiling tube 10e via hinges at intervals. Furthermore, in this embodiment, the current collector 6 having two boats 8A and 8B was described as an example, but the present invention can also be applied to a current collector having one boat. can. For example, in the case of a current collector having one boat body 8A shown in FIGS. , the area where the flow F directly collides with the lower surface of the boat body 8A can be reduced. As a result, the pressure-receiving area that receives the flow F that bounces the boat body 8A becomes smaller, and the positive pressure _PP generated on the lower surface side of the boat body 8A becomes smaller, so that the lift can be reduced.

(3) In this embodiment, the case where the hull 8A receives the flow F that pushes up the hull 8A has been mainly described, but the present invention can also be applied to the case where the hull 8A receives the flow F that pushes down the hull 8A. can do. For example, when the boat 8A receives a flow that blows down toward the boat 8A, the flow F can pass through the opening 24A from above to below the boat 8A. As a result, it is possible to suppress an increase in the positive pressure _PP on the upper surface side of the boat body 8A, thereby suppressing a change in lift force. Further, for example, the direction of the flow F separated at the lower corner of the boat body 8A can be changed by the flow F flowing downward from the opening 24A of the boat body 8A. As a result, it is possible to suppress the generation of a vortex behind the boat body 8A, thereby suppressing an increase in the negative pressure P _N on the underside of the boat body 8A and suppressing a change in lift force.

(4) In this embodiment, the case where the openings 24A and 24B are formed substantially continuously between the adjacent connection portions 8j in the longitudinal direction of the boat bodies 8A and 8B has been described as an example. is omitted and the openings 24A and 24B are formed continuously in the longitudinal direction of the boat bodies 8A and 8B. Further, in this embodiment, the boat bodies 8A and 8B assembled by pressing a single long plate have been described as an example. The present invention can also be applied to bodies 8A and 8B. Furthermore, in this embodiment, the cross-sectional shape of the boat bodies 8A and 8B is substantially C-shaped or substantially U-shaped. The present invention can also be applied to cases of arbitrary shapes.

(5) In this embodiment, the boats 8A and 8B are plate-shaped. . In this case, openings can be formed in the lower and upper parts of the cylindrical hull, penetrating from the lower part to the upper part of the hull. In the second embodiment, the openings 24A and 24B are formed substantially continuously between one end and the other end of the boat bodies 8A and 8B having a substantially U-shaped cross section as an example. As described above, the openings 24A and 24B are formed in the central portion of the boat bodies 8A and 8B having a substantially U-shaped cross section, and the openings 24A and 24B are formed in one end and the other end. The present invention can also be applied to cases. Furthermore, in the fifth embodiment, the description has been given by taking as an example the case where the boat bodies 8A and 8B having a substantially C-shaped cross section are applied. , the present invention can be applied.

(6) In the sixth and seventh embodiments, the inclined portions 25b of the positive pressure reducing portions 25A and 25B and the inclined portions 26a and 26b of the rectifying portions 26A and 26B are flat inclined surfaces. However, the present invention can also be applied to a curved surface or a streamlined inclined surface. In the sixth and seventh embodiments, the case where the positive pressure relief portions 25A and 25B include the lower portion 25f has been described as an example. The present invention can also be applied to the case of directly connecting the . Similarly, in the sixth and seventh embodiments, the positive pressure relief portions 25A and 25B have side portions 25d. The present invention can also be applied to a case where the portion 25c is directly connected.

1 overhead wire 1a trolley wire 2 track 3 vehicle 5 vehicle body 5a side surface 5b roof 5c shoulder 6 current collector 7A, 7B slider 8A, 8B boat body 8a upper portion 8b side portion (front side portion)
8c side (rear side)
8d lower part (front lower part)
8e lower part (rear side lower part)
8g Upper surface 8h Lower surface 8i Attachment portion 8j Connection portion 10 Boat support portion 11 Framework 23 Lift change suppression structure 24A, 24B Opening portion 24a Inlet 24b Outlet 24c Flow path 25A, 25B Positive pressure relaxation portion 25b Inclined portion 26A, 26B Straightening portion 26a, 26b Inclined portion F Flow H ₁ , H ₂ Height Positive pressure _PP
Negative pressure _PN
Direction of D ₁ , D ₂

Claims (14)

A lift change suppression structure for a hull that suppresses a change in the lift acting on the hull when the hull receives a flow that changes the lift acting on the hull of the concentrator,
providing an opening vertically penetrating the hull and opening at the upper and lower surfaces of the hull;
A hull lift change suppression structure characterized by: In the lift change suppression structure of the hull according to claim 1,
the opening is formed substantially continuously between one end and the other end of the boat;
A hull lift change suppression structure characterized by: In the lift change suppression structure of the hull according to claim 1,
The opening is formed in the central portion of the hull;
A hull lift change suppression structure characterized by: In the lift change suppression structure of the hull according to claim 1,
The openings are formed at one end and the other end of the hull;
A hull lift change suppression structure characterized by: In the hull lift change suppression structure according to any one of claims 1 to 4,
comprising a positive pressure relief portion that relieves the positive pressure generated on the lower surface side of the hull;
A hull lift change suppression structure characterized by: In the lift change suppression structure of the hull according to claim 5,
the positive pressure relief part relieves blockage of a flow directed upward from below on the lower surface side of the hull;
A hull lift change suppression structure characterized by: In the hull lift change suppression structure according to claim 5 or claim 6,
The positive pressure relief section has a lower portion on the rear side of the hull and lower in height than the front side of the hull;
A hull lift change suppression structure characterized by: In the lift change suppression structure of the hull according to claim 5,
the positive pressure relief part relieves blockage of a flow directed upward from below on the lower surface side of the boat body, and generates a negative pressure on the lower surface side of the boat body;
A hull lift change suppression structure characterized by: In the lift change suppression structure for the hull according to claim 5 or claim 8,
The positive pressure relief section has an inclined section on the rear side of the hull that inclines obliquely upward from the front to the rear;
A hull lift change suppression structure characterized by: In the lift force change suppression structure for the hull according to any one of claims 5 to 9,
comprising a rectifying section that guides the flow toward the positive pressure relieving section;
A hull lift change suppression structure characterized by: In the lift change suppression structure for the hull according to claim 10,
the straightening unit generates a negative pressure on the lower surface side of the boat body;
A hull lift change suppression structure characterized by: In the lift change suppression structure for the hull according to claim 10 or 11,
The rectifying section has an inclined section that inclines obliquely upward from the front to the rear at the lower front side of the boat body;
A hull lift change suppression structure characterized by: In the hull lift change suppression structure according to any one of claims 10 to 12,
The rectifying section has a sloped section that slopes obliquely upward from the rear to the front at the lower front side of the boat body;
A hull lift change suppression structure characterized by: In the lift force change suppression structure for the hull according to any one of claims 1 to 13,
The hull is a hull of a current collector of a vehicle running on a conventional line;
A hull lift change suppression structure characterized by:

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