JPS63266232A - Experimental specimen fall braking device of gravity free experimental installation - Google Patents

Abstract

PURPOSE:To brake a falling specimen in the lower end space of a falling tower so as to securely stop it with out any strong shock by arranging elastic plate members, the through hole diameters of which in the center of the falling tower are gradually reduced at intervals of plural stages. CONSTITUTION:Many rubber made elastic disc plate members 3, 3', 3'' having circular through holes 4, 4', 4'' in their centers are arranged at intervals in the lower end space of a falling tower 1 formed underground and the diameter of any plate member is reduced as its position is lower. Elastic plate members 5, 5', 5'' having no holes are arranged in the same way below them and a fixed damper 6 such as a spring, etc., is provided on a bottom for emergency. Accordingly, the falling specimen (payload) 2 gradually receives a gradually growing frictional resistance successively from the elastic plate members 3, 3', and its falling energy is effectively absorbed to be stopped. In an emergency, it stops by the aid of the elastic plate members 5, 5'... and the fixed damper 6 and safety may be secured. Therefore, the falling energy of the experimental specimen is not drastically absorbed to be surely stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a braking device for dropping an experimental specimen in a zero-gravity experimental facility.

[Conventional technology and its problems]

It is known that it is possible to create a zero-gravity state within an object by free-falling it over a relatively long distance.As part of the underground development and utilization structure, a long drop tower was built underground, and experimental objects were placed inside it. A zero-gravity experimental facility is being considered in which specimens (hereinafter referred to as payloads) are allowed to fall freely and materials and biological experiments are conducted on the ground in preparation for manufacturing experiments in the zero-gravity of space.

For example, if the payload is allowed to fall approximately 500 meters, approximately 1
A zero-gravity state can be created for 0 seconds, but as mentioned above, a drop tower installed underground would also be as long as 100 m or several 100 m.

One of the important technical points in such a zero-gravity experimental facility is how to brake the falling payload at the lower end of the drop tower to ensure that it stops. However, the payload is recovered after falling and the experimental materials inside are removed, and if the payload is damaged or subjected to a strong impact from the outside, proper experimental results will not be obtained.

Conventionally considered braking methods are not suitable for zero-gravity experimental facilities that utilize free fall, and methods such as installing a sand bit filled with sand at the bottom of the drop tower, applying braking with magnetic force, and using hydraulic cylinders, etc. However, in this case, the braking device itself is very special and expensive, and it is also difficult to perform maintenance and inspection.

SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus for braking the fall of an experimental specimen in a zero-gravity experimental facility, which eliminates the disadvantages of the conventional example, provides reliable control, has a simple structure, and is inexpensive.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention provides a zero-gravity experimental facility in which a test specimen is allowed to fall freely in a drop tower to obtain a zero-gravity state, and is provided with a plurality of stages of elastic plates whose center through-hole diameter gradually decreases. The main point is that the

[Function] According to the present invention, the falling payload enters the through hole of the uppermost elastic plate, the falling energy is slightly reduced by the frictional resistance of the plate, and then the falling payload enters the through hole of the uppermost elastic plate, and then falls into the second elastic plate. It enters the through hole and reduces the falling energy with slightly stronger frictional resistance than the previous plate. In this way, each time the payload passes through the through-hole of the elastic plate, the diameter of the through-hole gradually decreases, so the frictional resistance increases, the falling energy is gradually and reliably absorbed, and the payload comes to a stop.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

Fig. 1 is a longitudinal sectional front view showing one embodiment of the test specimen fall braking device for a zero-gravity experimental facility of the present invention, in which 1 is a falling platform formed underground, and 2 is a falling platform 1 that is allowed to fall freely. Shows the payload (experiment specimen).

The falling base 1 is made of a long cylinder made of concrete or metal and has an inner diameter of about 1 m to 50 m, and has a tapered lower end, for example. Although not shown in the drawings, the payload 2 is a circular capsule that stores experimental materials, etc., and has a bullet-like shape with a rounded tip.

At the lower end of such a drop base 1, there is a circular through hole 4 in the center.
Disc-shaped elastic plates 3, 3 made of rubber material provided with 4', 4''
A large number of through-holes 4, 4', 4', 4', 4', etc. are arranged at vertical intervals, and the diameter of these through-holes gradually decreases toward the lower plate as shown in Figure 2. shall be reduced.

The diameter of the through hole 4 of the uppermost elastic plate 3 is the same as or slightly larger than the diameter of the payload 2, and the diameter of the lowermost elastic plate is very small. Further below, there is an elastic plate 5, 5°, 5 pa... with no through holes at all.
Several pieces of ・ were placed at similar intervals.

Furthermore, a fixed damper 6 made of a spring or the like is attached to the bottom of the drop base 1 in case of an emergency.

These elastic plates are 3.3", 3'1... and 5.5'5
In addition to natural or synthetic rubber materials, a plastic material having elasticity such as a thermoplastic elastomer may be used as the material.

Furthermore, elastic plate members 3.3', 3"...l' 51 5
' 1511... is fixed and attached to the lower end of the drop base 1, and a casing 8 that can be pulled up to the ground with a lifting member 7 such as a wire rope is set inside the drop base 1 as shown in Figure 3. And inside this is an elastic plate 3.3°.

311..., 5.5', 5"..., and the payload 2 that has been stopped as in the embodiment shown in FIG. 3 can be recovered by pulling up the casing 8. Easy to do.

In addition, the elastic plate 3゜31.3 disposed inside the casing 8
11. , can be attached freely inside the casing 8 by bolting or other means as shown in Fig. 4, and if the size of the payload 2 is different, an elastic plate with a thickness corresponding to the size of the payload 2 can be used. 3.3°.

31''... can be attached, and furthermore, the worn out elastic plates 3, 3°, 3''... can be easily replaced.

Next, the usage and operation will be explained. The payload 2 is caused to fall freely from the top fall starting point of the drop base 1.

The tip of the fallen payload 2 hits the central through hole 4 of the uppermost elastic plate 3 at the lower end of the falling base 1, touches the plate 3, and some of the falling energy is absorbed by the frictional resistance.

Next, the tip of the payload 2 is attached to the second and third plate bodies 3.
The payload 2 is plate 3”, 3
The frictional resistance created by the payload 2 gradually increases, and the number of slopes that come into contact with the payload 2 also increases, so the falling energy is effectively absorbed and the payload 2 comes to a stop.

In addition, suppose that the payload 2 has all the through holes 4°4', 4
Even if it falls through the elastic board 5.5",
5"... or the fixed damper 6, safety can be ensured.

〔Effect of the invention〕

As described above, the test specimen fall braking device for a zero-gravity experimental facility of the present invention can be used in a zero-gravity experimental facility where a test specimen is allowed to fall freely to obtain a zero-gravity state, and can be used without suddenly absorbing falling energy. It can brake a specimen, has a simple structure, can be manufactured at low cost, and can be easily repaired.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional front view showing one embodiment of the test specimen drop braking device for a zero-gravity experimental facility of the present invention, Fig. 2 is a perspective view of the same main part, and Fig. 3 is a main part showing another embodiment. vertical front view of
FIG. 4 is a longitudinal sectional front view of a main part showing still another embodiment. 1... Drop base 2... Payload 3.3"
, 3゛1......Elastic plate 4.4°, 4 parts...
...Through hole 5.5', 5''...Elastic plate body 6...Fixed damper 7...Lifting member 8...Casing applicant Kajima Corporation Figure 2 Figure 4 Figure 3

Claims (3)

[Claims] (1) A zero-gravity experiment in which an experimental specimen is allowed to fall freely in a drop tower in a zero-gravity experimental facility, and an elastic plate whose central through-hole diameter gradually decreases is arranged at multiple stage intervals. Facility's test specimen fall braking system. (2) An experimental specimen fall braking device for a zero-gravity experimental facility according to claim 1, wherein the elastic plate is disposed within a casing that can be pulled up. (3) An experimental specimen fall braking device for a zero-gravity experimental facility according to claims 1 and 2, wherein the elastic plate is detachably arranged.