JP5458002B2 - Mobile model for launcher - Google Patents

Description

  The present invention relates to a moving body model used for an experiment performed to reproduce an aerodynamic phenomenon such as a compression wave generated by a moving body moving at high speed.

When a moving body such as a railway train enters the tunnel at high speed, a compression wave is generated at the entrance of the tunnel and propagates in the direction of the exit. The compression wave propagating in the tunnel emits a pulsed pressure wave at the tunnel exit or vibrates another moving body traveling in the tunnel. A pulsed pressure wave radiated from the tunnel exit is called a tunnel micro-pressure wave, and it may generate blasting sound from the wellhead or shake the house fixture near the wellhead.
In order to elucidate this phenomenon, a compression wave reproduction experiment using an apparatus for launching a moving body model is performed. FIG. 5 shows the configuration of a compression wave reproduction experiment apparatus. When the moving body is a railway train or the like and cannot be manufactured in full size, the moving body model 1 is manufactured at an appropriate scale. The moving body model 1 is sandwiched between a pair of upper and lower launch wheels 21. The launch wheel 21 rotates at a high speed in different directions, thereby applying a driving force to the moving body model 1 by friction and accelerating the moving body model 1. There may be one pair of firing wheels 21 or a plurality of pairs.
The accelerated moving body model 1 is launched from the launching device 2. The launched mobile model 1 enters the tunnel model 4 while being guided by the piano wire 3. The pressure fluctuation generated at this time is measured with a pressure gauge installed at an appropriate location.

The moving speed of the moving body model 1 is measured using a magnet 18 embedded in the rear end of the moving body model 1. That is, if the coils 5 are provided at a plurality of locations on the movement path and the voltage generated in the coils 5 when the moving body model 1 passes through these coils 5 is measured, the distance between the coils and the time difference between the voltages are measured. The moving speed of the body model 1 can be calculated.
The moving body model 1 that has passed through the tunnel model 4 is finally stopped by the stop device 6. The stopping device 6 is a so-called cushion, and the moving body model 1 stops when the moving body model 1 hits the stopping device 6.

  Since it is necessary to pass the piano wire 3 for guidance to the moving body model 1, it manufactures so that a division | segmentation is possible. FIG. 9 shows a state where the conventional moving body model 1 is divided. Each divided part will be called a main body part 11. In FIG. 9, the main body portion 11 including the front end portion 15 and the intermediate main body portion 11 are shown. FIG. 10 is a view showing a joint portion of the conventional mobile model 1, and FIG. 11 is a cross-sectional view showing coupling of the conventional mobile model 1. In order to connect each of the divided main body portions 11 at each cross section of the movable body model 1, a male screw 13 is provided in one main body portion 11 and an opening 7 is provided in the other main body portion 11 across the cross section. A female screw 14 is formed on the inner side, and a male screw 13 is screwed into and coupled to the female screw 14.

There are several prior art techniques for joining long objects.
Patent document 1 is a prior art regarding the coupling structure of a casing pipe. The end of the other casing pipe can be inserted inside one casing pipe, and they are screwed together with the provided screws.
Patent document 2 is a prior art regarding a pipe joint structure. Tubes can be inserted to the left and right of the joint, and a female thread is provided on the inner circumference of the cylinder of the joint, and a male thread is provided on the outer circumference of the retainer installed at the end of the pipe. As a result, the tubular bodies are joined.
However, in any structure, the diameter of the pipe (tubular body) changes at the joint, but the moving body model imitating a railroad train is divided without changing its cross-sectional area, A structure that can be combined is required.

Japanese Patent Laid-Open No. 2001-200685 JP 2002-243075 A

As shown in FIG. 10, in order to reduce the weight, the conventional moving body model 1 has been hollowly formed by cutting the main body portion from the cross section in the longitudinal direction. On the other hand, conventionally, when the launched moving body model 1 collides with the stop device 6 (see FIG. 8), stress due to impact is concentrated on the male screw corresponding to the connecting portion of the moving body model 1, and the male screw at the joint portion. Could be damaged. Therefore, measures have been taken to increase the thickness of the male screw (thickness d2 in FIG. 10) in order to increase the strength of the male screw. However, since the male screw is integrally formed with the main body portion, the moving body model 1 is Even if it is intended to be hollow, there is a problem that when the thickness (d2) of the male screw is increased, the amount of the body model 1 is reduced and the total weight of the movable body model 1 is increased.
The increase in the weight of the moving body model 1 increases the load on the launching device and the stopping device, and makes the handling of the moving body model 1 difficult.

Further, as shown in FIG. 12, in the conventional moving body model 1, since the magnet 18 is embedded in the rear end portion 16, the rear end portion 16 of the moving body model 1 has a hole 19 for embedding the magnet 18. The surface was bumpy. In the compression wave reproduction experiment, since it is necessary to make the change rate of the cross-sectional area of the moving body model 1 equivalent to the reality, it is not preferable that the surface of the front end portion 15 is uneven. Accordingly, when the moving body model 1 repeatedly collides with the stopping device 6 and the front end portion 15 of the moving body model 1 is damaged or deformed, the rear end portion 16 cannot be replaced with the front end portion 15, and the front end portion 15 There is a problem that it is necessary to manufacture the portion 15 again, and the burden is large in terms of time and economy.
Further, an impact force is applied to the magnet 18 embedded in the rear end portion 16, and the hole 19 and the lid 20 in which the magnet 18 is embedded are damaged, so that the magnet 18 may rattle or jump out.

In order to solve these problems, the present invention provides a moving body model 1 that does not break the joint portion 12 even if the moving body model 1 repeatedly collides with the stop device 6 and is light in weight and easy to handle. For the purpose.
Further, even if the moving body model 1 repeatedly collides with the stopping device 6 and the front end portion 15 is damaged, the moving body model 1 can be replaced at low cost by replacing the front end portion 15 with the rear end portion 16. For the purpose.

  Hereinafter, the present invention will be described with reference numerals. However, the reference numerals are for reference, and the present invention is not limited to the embodiments.

  In order to achieve the above object, a first invention according to the present application is a movable body model 1 for a launcher that can be divided into a plurality of sections in a cross-section substantially perpendicular to the traveling direction, and a plurality of the main body portions 11 and The number of the joint portions 12 is one less than the number of the main body portions 11, and at least one of the joint portions 12 includes a magnet 18, and the main body portions 11 are provided in a cross section. The movable body model 1 is constituted by connecting the joint parts 12 by inserting the joint parts 12 into the open openings 7.

  Moreover, 2nd invention which concerns on this application is so that the shape of the main body part 11 of the advancing direction edge part and the main body part 11 of the advancing direction opposite side edge part may become congruent among the said several main body parts 11. FIG. I made it.

  Further, according to a third aspect of the present invention, a female screw 14 is formed in the opening 7 provided in the cross section of the main body portion, and a male screw 13 is formed on the surface of each joint portion. The movable body model 1 is configured by being connected to each other by screwing the joint portion.

  By configuring in this way, the thickness of the joint portion 12 (thickness d1 in FIG. 2) can be increased and the strength thereof can be increased, so that the male screw 13 provided in the joint portion is not damaged. . On the other hand, since the main body portion 11 independent of the joint portion 12 can be cut out from the cross section, it can be formed to have an arbitrary thickness to reduce the weight.

  Furthermore, with this configuration, even if the moving body model 1 repeatedly collides with the stopping device 6, the magnet 18 is built in the joint portion 12 included in the main body, so that the magnet 18 is not stable. There is no.

  Further, with such a configuration, the problem that the surface of the moving body model 1 is bumpy at the rear end portion 16 of the moving body model 1 cannot occur, and as a result of repeated collisions of the moving body model 1 with the stop device 6, the moving body model Even if the front end 15 of 1 is broken, the shape of the front end 15 and the rear end 16 is congruent. Therefore, if the main body part at the opposite end in the traveling direction and the main body part at the traveling direction end are exchanged, The moving body model 1 can be used again for the compression wave reproduction experiment. Therefore, such a configuration is economical and does not require time for manufacturing the front end portion 15 for replacement.

It is a figure showing the external appearance of a mobile body model. It is a figure showing the coupling | bonding of the mobile body model which concerns on this invention. It is a figure showing the joint part in which the magnet was built among the joint parts which concern on this invention. It is sectional drawing showing the coupling | bonding of the mobile body model which concerns on this invention. It is a figure showing the structure of the reproduction wave reproduction experimental device. It is a figure showing the structure of the emission device of the reproduction wave reproduction experimental device. It is a figure showing the tunnel model and coil of a reproduction wave reproduction experimental device. It is a figure showing the stop apparatus of the reproduction wave reproduction experimental device. It is a figure showing the coupling | bonding of the conventional mobile body model. It is a figure showing the main-body part containing the front-end part of the conventional mobile body model. It is sectional drawing showing the coupling | bonding of the conventional mobile body model. It is a figure showing the magnet incorporated in the rear-end part of the conventional mobile body model. It is a figure showing the correspondence example of the head shape of various trains, and the shape of the front-end part of a moving body model. It is a conceptual diagram of the compression wave generated when a railroad train enters a tunnel.

[Moving object model according to the invention]
The moving body model 1 according to the present invention will be described.

  FIG. 1 is a diagram showing the appearance of the moving body model 1. The scale of the moving body model 1 is usually 1/60 to 1/100. Since the moving body model 1 needs to pass the guiding piano wire 3, it has a structure that can be divided into a plurality of sections in a cross section substantially perpendicular to the traveling direction. In FIG. 1, a movable body model 1 that can be divided into four main body parts is shown. However, in order to change the length of the movable body model 1 in the longitudinal direction according to the purpose of the reproduction experiment, two or more What is necessary is just to comprise from a main-body part. The piano wire 3 is passed through the center of the cross section.

  FIG. 2 is a view showing the coupling of the moving body model 1 according to the present invention, and shows a main body portion 11 including a front end portion 15, an intermediate main body portion 11, and these joint portions 12. FIG. 4 is a sectional view showing the coupling of the moving body model 1 according to the present invention. Each section of the divided main body portion 11 is provided with an opening 7 in the section in order to connect each section. Further, the number of joint portions 12 that can be inserted into the openings 7 is one less than the number of the main body portions 11, and the main body portions 11 are connected to each other by inserting the joint portions 12 into the openings 7 provided in the cross section. And if all the main-body parts 11 are connected in all the cross sections, the mobile body model 1 will be comprised.

  In the present embodiment shown in FIG. 2, a female screw 14 is formed inside the opening 7 of the main body portion 11, a joint portion 12 is formed in a cylindrical shape, and a male screw 13 is formed on the outer curved surface thereof. 13 and the female thread 14 of the main body 11 are screwed together. By comprising in this way, the mobile body model 1 becomes easy to divide and combine. FIG. 4 is a diagram illustrating the coupling of the moving body model 1 according to the present embodiment. The coupling between the main body portion 11 and the joint portion 12 may be a mechanical coupling such as spline coupling or fitting.

  At least one of the joint portions 12 is provided with four holes 19 in the longitudinal direction of the movable body model 1 for embedding the magnet 18. FIG. 3 shows the joint portion 12 in which the magnet 18 is built in the joint portion 12 according to the present invention. A magnet 18 is embedded in each hole 19, and the magnet 18 is built in the joint portion 12.

  When conducting an experiment simulating a railway train as a moving body, the front end portion 15 and the rear end portion 16 of the moving body model 1 are often congruent. In general, in the case of a railway train, the shape of the front end 15 and the shape of the rear end 16 are substantially congruent.

  As shown in FIG. 1, the movable body model 1 is molded so as to be axially symmetric, that is, to have a circular cross section in the direction perpendicular to the traveling direction, for ease of model manufacture and ease of handling.

The moving body model 1 is manufactured by cutting a rod-shaped raw material with a lathe. By using a lathe, the cross section perpendicular to the traveling direction becomes circular, but the cross sectional shape of the moving body model 1 does not affect the compression wave reproduction experiment as described later.

  As shown in FIG. 1, the front end portion 15 and the rear end portion 16 of the moving body model 1 may be molded so that the cross-sectional area decreases as the tip ends. The shape of the rear end portion 16 is determined by the shape of a moving body (a railway train in this embodiment) to be reproduced. In order to reproduce the compression wave generated in the tunnel, the ratio of the cross-sectional area of the tunnel model 4 to the cross-sectional area of the mobile body model 1, the cross-sectional area change rate of the front end portion 15 of the mobile body model 1, and the movement This is because it is necessary to make the speed at which the body model 1 enters the tunnel model 4 equivalent to the reality. That is, in an experiment simulating a railroad train, the shape of the front end portion 15 and the rear end portion 16 is generally cylindrical if an attempt is made to reproduce a gable-type commuter train that is normally found in Japan. On the other hand, if an attempt is made to reproduce a streamlined train such as a high-speed train, the cross-sectional areas of the front end portion 15 and the rear end portion 16 become smaller toward the front end. FIG. 13 shows the top shape of a gable-type vehicle (commuter train), streamlined vehicle (high-speed train), and an intermediate type (express train) thereof, and the shape of the front end portion 15 (or the rear end portion 16) of the moving body model 1. An example of correspondence is shown.

[Compression wave reproduction experiment]
The moving body model according to the present invention is mainly used for a compression wave reproduction experiment. Hereinafter, a compression wave reproduction experiment will be described.

When the moving mobile body enters the tunnel, the compression wave generated at the entrance of the tunnel propagates in the tunnel toward the exit at the speed of sound. This compression wave gives vibration to another moving body that travels in the tunnel, or when it reaches the tunnel exit, a part of it is radiated to the outside as a pulsed pressure wave to generate low-frequency sound. In addition, the compression wave reflected at the tunnel exit may give vibration to the moving body itself traveling through the tunnel. The pulsed pressure wave radiated at the tunnel exit is called tunnel micro-pressure wave. FIG. 14 shows a mechanism for generating a compression wave.
In order to elucidate this phenomenon, an experiment using a device that launches a moving body model and enters a tunnel model is conducted. Here, a railroad train is described as an example of the moving body, but the moving body may be another moving body such as an automobile.

[Configuration of experimental apparatus]
FIG. 5 shows the configuration of a compression wave reproduction experiment apparatus. Usually, a model cannot be produced in full scale because an experiment simulating a railway train as a moving body is performed. For this reason, a model is manufactured at an appropriate scale and an experiment is performed.
FIG. 5 shows the configuration of a compression wave reproduction experiment apparatus. This experimental apparatus is composed of a model launching device 2, a piano wire 3, a tunnel model 4, a coil 5, a stopping device 6, and a moving body model 1.

[Model launcher]
The model launching device 2 is a device for launching the moving body model 1 toward a tunnel model 4 described later. FIG. 6 shows the configuration of the launching device 2. Although there are three pairs of launch wheels 21 in FIG. 6, one or more pairs of launch wheels 21 may be used according to the purpose of the experiment and the scale of the experiment. Further, although the launch wheels 21 are installed up and down in FIG. 6, they can be installed horizontally or diagonally so as to sandwich the moving body model 1.

  The launch wheel 21 is for accelerating the movable body model 1 by friction drive. The launch wheels 21 are paired one above the other. The launching wheel 21 sandwiches the moving body model 1 from above and below and rotates at high speed in different directions, thereby applying a driving force to the moving body model 1 by friction and accelerating the moving body model 1.

  The moving body model 1 before being launched from the launching device 2 is installed in front of the launching wheel 21. At the time of launching, the moving body model 1 is sent out between the launching wheels by a spring (not shown), is accelerated by friction by the launching wheel 21, and is launched toward the tunnel model 4. For example, in the launching device 2 of the present embodiment, when the mobile body model 1 is to be accelerated to 300 km / h, the three launch wheels 21 gradually increase in rotational speed from the side far from the tunnel model 4 to finally Is rotated at a speed of 300 km / h to accelerate the moving body model 1.

[Piano wire]
The piano wire 3 is installed on the moving path of the moving body model 1 in order to guide the moving body model 1. As shown in FIG. 5, both ends of the piano wire 3 are fixed to the tensioning device 31. The tension is applied to the piano wire 3 to such an extent that it does not hang down. In this example, a piano wire having a diameter of 5 mm was used. Instead of the piano wire 3, other suitable materials such as other steel wires and nylon wires can be used according to the purpose and scale of the experiment. Further, the thickness of the piano wire 3 can be changed according to the purpose of the experiment.

[Tunnel model]
FIG. 7 is a diagram illustrating the tunnel model 4 and the coil 5. The tunnel model 4 is a model simulating a tunnel. In this example, a transparent acrylic tube was used.

  Here, in order to reproduce the phenomenon of the tunnel micro-pressure wave, the ratio between the cross-sectional area of the tunnel model 4 and the cross-sectional area of the moving body model 1, the cross-sectional area change rate of the front end portion 15 of the moving body model 1, and What is necessary is just to reproduce the speed of the mobile body model 1 equivalent to reality. Therefore, in this embodiment, the cross section of the tunnel model 4 is circular, but the cross section of the tunnel may be an actual real cross section of the tunnel.

  In this embodiment, a transparent acrylic tube is used from the viewpoint of ease of manufacturing, availability, and cost, but other materials such as plastic such as polyvinyl chloride are used. A resin water pipe may be used. However, as will be described later, since the moving speed of the moving body model 1 is measured using the coil 5 and the magnet 18, the material of the tunnel model 4 is preferably one that transmits magnetic force.

[coil]
The speed of the moving body model 1 can be measured by the voltage generated when the magnet 18 embedded in the moving body model 1 passes through the coil 5 installed in the moving path of the moving body model 1. FIG. 7 shows an example in which the coil 5 is installed near the entrance and exit of the tunnel model 4.

Specifically, coils are installed at two or more locations on the moving path of the moving body model 1 so as to surround the piano wire 3. When the moving body model 1 passes through these coils 5, a voltage is generated in the coil by a magnet embedded in the moving body model 1. If the coils 5 are installed at two or more places, the speed of the moving body model 1 can be calculated by dividing the distance between the coils 5 by the difference in time when the voltage is generated in each coil 5.
In this embodiment, the coils 5 are installed at two locations near the entrance and the exit of the tunnel model 4, but the coils 5 may be installed at three or more locations. For example, if two coils are installed near the entrance of the tunnel model 4 and two places near the exit, the speed when the moving body model 1 enters the tunnel model 4 and the speed when it escapes from the tunnel model 4 Can be measured.

[Stopping device]
The launched mobile model 1 collides with the stop device 6 and stops. FIG. 8 is a diagram showing the stop device 6. The stopping device 6 is a so-called cushion, and the moving body model 1 stops when the moving body model 1 hits the stopping device 6. The stop device 6 is installed behind the tunnel model 4 (moving direction of the moving body model). In this embodiment, a sponge is used as the cushion material 61 of the stopping device 6. Since the moving body model 1 may reach a speed of 500 km / h, which is similar to the speed of a high-speed railway, the cushioning material 61 has a sufficient thickness and softness so as not to be destroyed when the moving body model 1 collides with the stopping device 6. Is used to manufacture the stop device 6.

[Compression wave reproduction test using the moving body model of the invention]
Next, a compression wave reproduction experiment using the moving body model 1 will be described step by step.

  When the moving body model 1 is fired, first, the moving body model 1 is installed in front of the launching wheel 21 on the most front side (opposite direction of travel) of the launching wheels 21 of the launching device 2. Next, the launching wheel 21 is rotated, and when the set number of revolutions is reached, the moving body model 1 is sent out to the launching wheel 21 by a spring, and the moving body model 1 is accelerated by friction drive. The plurality of pairs of launch wheels 21 are adjusted so that the rotational speed gradually increases from the front, and the moving body model 1 gradually accelerates each time it moves to a pair of adjacent launch wheels 21. Then, the rotation speed of the launch wheel 21 is adjusted so that the speed when passing through the last launch wheel 21 becomes the moving speed obtained by the experiment.

  When there are a plurality of pairs of launch wheels 21, the length of the movable body model 1 in the longitudinal direction needs to be shorter than the interval between the launch wheels 21. That is, when the moving body model 1 is gradually accelerated by a plurality of pairs of launching wheels 21, the rotational speed differs between the adjacent launching wheels 21, so that the longitudinal length of the moving body model 1 is the launching wheel. If the interval is longer than 21, the force in the longitudinal direction is applied to the movable body model 1, causing the movable body model 1 to be damaged. Therefore, the length of the moving body model 1 in the longitudinal direction needs to be the same or shorter than the interval between the launch wheels 21.

  The fired moving body model 1 enters the tunnel model 4. At this time, a compression wave is generated at the entrance of the tunnel model 4 and propagates in the tunnel model in the exit direction (traveling direction side). This is measured using a pressure gauge (not shown).

  The moving speed of the launched moving model 1 is calculated from the difference in time when the voltage generated when passing through the coils 5 installed at two or more places.

  The moving body model 1 that has passed through the tunnel model 4 collides with the stop device 6 installed at the tip (traveling direction side) of the tunnel model 4 and stops.

  By using the moving body model 1 according to the present embodiment for the compression wave reproduction experiment, the following effects can be obtained.

  When the launched mobile model 1 collides with the stop device 6 and stops, stress due to the impact concentrates on the joint portion 12 of the mobile model 1. Further, the front end portion 15 of the moving body model 1 is gradually worn out as the collision is repeated. However, if the moving body model 1 is configured as in the present invention, the thickness of the joint portion 12 (thickness d1 in FIG. 2) can be increased and the strength thereof can be increased. Will not be damaged.

  Even if the front end portion 15 of the moving body model 1 collides with the stop device 6 and wears, the surface of the rear end portion 16 of the moving body model 1 is smooth and has no unevenness, and the shape is the same as that of the front end portion 15. Therefore, the main body portion 11 including the rear end portion 16 and the main body portion 11 including the front end portion 15 can be exchanged.

  Moreover, although the divided | segmented main-body part 11 can be made hollow, since each main-body part 11 is independent from the joint part 12, it can be made hollow irrespective of the thickness d1 of a joint part. If comprised in this way, weight reduction will be attained as the whole mobile body model 1, and the handling at the time of work will become easy. Further, even when trying to give the same firing speed, if the moving body model 1 is lightweight, the driving force applied to the moving body model 1 by the launching device 2 can be reduced. Furthermore, the load on the stopping device 6 due to the collision of the moving body model 1 can be reduced.

  Further, if the coupling unit 12 includes the magnet 18, the built-in magnet 18 is inside the main body portion 11 even if the fired moving body model 1 repeatedly collides with the stopping device 6. Compared to the moving body model 1, the magnet 18 is not easily damaged, and the magnet 18 does not jump out by impact.

  The front end portion 15 and the rear end portion 16 of the movable body model 1 may be molded so that the cross-sectional area decreases as the tip ends. In order to reproduce the compression wave, the ratio of the cross-sectional area of the tunnel model to the cross-sectional area of the mobile body model 1, the cross-sectional area change rate of the front end of the mobile body model 1, and the mobile body model 1 This is because it is necessary to make the speed of entering the field equivalent to the reality. That is, in an experiment simulating a railroad train, the actual shape of a railroad train, in particular, a high-speed railcar, is often streamlined at the top, so that the cross-sectional area change rate of the moving body model 1 is equivalently reproduced. Moreover, it is because the moving body model 1 needs to be formed so that the cross-sectional area becomes smaller toward the tip.

DESCRIPTION OF SYMBOLS 1 Mobile body model 11 Main body part 12 Joint part 13 Male screw 14 Female screw 15 Front end part 16 Rear end part 17 Hollow 18 Magnet 19 Hole 20 Lid 2 Launcher 21 Launching wheel 3 Piano wire 31 Tensioner 4 Tunnel model 5 Coil 51 Voltmeter 6 Stop device 61 Cushion material 7 Opening

Claims (3)

A moving body model for a moving body model launcher,
The movable body model has a main body portion that can be divided into a plurality of sections in a cross section substantially perpendicular to the traveling direction;
The number of joints is one less than the number of the main body parts, and
At least one of the joint parts contains a magnet,
The main body parts are connected to each other by inserting the joint part into an opening provided in a cross section, and constitute the moving body model,
A moving body model characterized by Of the plurality of main body portions, the shape of the main body portion at the end portion in the traveling direction and the main body portion at the end portion on the opposite side in the traveling direction are congruent,
The moving body model according to claim 1. A female screw is formed in the opening provided in the cross section of each main body part, and a male screw is formed on the surface of each joint part.
The main body parts are connected to each other by screwing together with the joint part to constitute the movable body model,
The moving body model according to claim 1, wherein:

Images