JPS6152008A - Folded type parabolic antenna - Google Patents

Abstract

PURPOSE:To attain a light and folded antenna by forming a flexible and conductive clotch in a folded way so as to fit the cloth to a frame. CONSTITUTION:The frame 10 is supported to a center shaft 11 and a joint 15 fitted thereto turnably, and the antenna consists of plural wing bones 12 of a parabolic form, a bracket 13 slidable to the center shaft 10 and plural push-up bones 14 connecting the bracket 13 and the wing bones 12. The conductive cloth 20 is fitted to the wing bones 12 and the entire conductive cloth 20 form a paraboloid of revolution when the antenna is opened. The antenna is folded by sliding the bracket 13 along the center shaft 11 in this way and the volume of the antenna is drecreased at storage and transportation.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a parabolic antenna. In detail, this article relates to a foldable parabolic antenna.

<Prior art> In conventionally known circular parabolic antennas, a metal plate of about 5 mm thick, typically made of aluminum, is squeezed and pressed to form a curved surface as a reflector, and the curved metal plate is used for reinforcement. It is commonly attached to a supporting member using rivets or the like. At this time, the curved surface of the metal plate must be brought closer to the paraboloid of revolution in order to concentrate the reflection of radio waves on one point, and the processing machines that process the curved surface of the metal plate are extremely expensive and require many steps. is necessary. As a result, conventionally known parabolic antennas have the problem of being extremely expensive.

Further, parabolic antennas made of metal plates have problems in that they are heavy and therefore inconvenient to carry, and are large and require a large space to store.

On the other hand, with advances in the field of communication technology, it has become possible for individuals to easily obtain large amounts of information by simply installing a parabolic antenna. However, parabolic antennas of conventionally known structures have the problems of being expensive and difficult to handle as described above, making it difficult for a wide range of consumers to respond to the developments in the field of communication technology.

<Problems to be Solved by the Invention> As is clear from the above, conventionally known parabolic antennas have their own problems. SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a parabolic antenna that is lightweight, foldable, easy to use, and inexpensive.

Means for Solving the Problems> As a result of intensive research to solve the above problems, the present inventors used a flexible conductive fabric instead of the metal plate, and It has been discovered that the above-mentioned problems can be solved by attaching it to a frame that is foldably formed into an umbrella shape, and the present invention has been achieved.

That is, an object of the present invention is to provide a central axis, a plurality of wing spines rotatably supported at one point of the central axis, a bracket slidably attached to the central axis, the placket, and the plurality of wing spines. A foldable parabola comprising a foldable frame consisting of a plurality of raised bones connecting each of the wing spines, and a sheet-like material supported by the wing spines and covering the space between the wing bones. 1. A folding parabolic antenna, wherein the shape of the wing bones is determined so as to form a paraboloid of revolution when the parabolic antenna is opened, and the sheet-like material is made of conductive fabric. achieved by.

The reflector in a parabolic antenna is literally for reflecting radio waves, and in order to reflect radio waves, a material imparted with conductivity may be used as the reflector. In the foldable parabolic antenna according to the present invention, a conductive fabric is used as the material imparted with conductivity. Since it is made of cloth, it can be folded), and its weight t can be significantly reduced compared to a metal plate.

The conductive fabric used in the foldable parabolic antenna of the present invention may be formed by knitting and weaving yarns that have been given a conductive function in advance, or may be made by knitting and weaving yarns that are then given a conductive function. The yarn used may be a yarn made from any of synthetic fibers such as polyester and polyamide, and recycled fibers such as cupro and rayon. However, it is preferable to use fibers with high weather resistance. Alternatively, metal fibers such as aluminum, nickel, stainless steel, etc. may be knitted and woven and used as they are as a reflector. Even in this case, the reflector can be made much lighter than a metal plate.

When using an ffl fiber material, various methods can be used to impart conductive functionality to the fiber material in the form of a single thread or a fabric. For example, chemical plating, electroplating, or a combination of these methods on yarn or fabric, vacuum deposition method, ion blating method, sputtering method, metallic paint coating by combining metal powder with paint, and various types of fibers on R weft threads. A method may be used in which the entire yarn is metallized by compositing the threads, or their collapse may be used.

The radio wave reflection property imparted to the conductive fabric is evaluated in terms of electromagnetic shielding effect. The electromagnetic shielding effect required for general electrical equipment is 10 KHz to 1000
It is set to be 30 dB or less in the μH2 regulated frequency range. On the other hand, the frequency range used in space communications involving the parabolic antenna of the present invention is from 3 GHz to 26 GHz.
It is a very short wave of GHz. Therefore, the conductive fabric used in the parabolic antenna of the present invention is preferably configured to have radio wave reflection performance, that is, an electromagnetic wave shielding effect in this frequency range. Such a configuration is achieved by increasing the amount of metal in the conductive fabric.

However, as a practical matter, providing radio wave reflection performance over the entire range tends to impede the low cost, which is one of the characteristics of the parabolic antenna of the present invention. Therefore, 12G is a highly practical parabolic antenna.
If it has an electromagnetic wave shielding effect of 20 dB or more at the H2 frequency, it can provide sufficient radio wave reflectivity for the normally usable frequency range.

If the electromagnetic shielding effect is less than 20 dB, the performance as a parabolic antenna is too low to be practical, and if an electromagnetic shielding effect of 80 dB or more is required, it would be better to use a metal plate in terms of performance and price. It is effective as a whole. Therefore, when a conductive fabric is used as in the present invention, the configuration of the conductive fabric and the configuration of the framework of the parabolic antenna, such as the diameter of the parabolic antenna, should be determined with the aim of achieving an electromagnetic shielding effect of 20 dB or more and 80 dB or more. I really like it.

The structure of the foldable parabolic antenna of the present invention is similar to that of an ordinary umbrella, and various types of frame structures and conductive fabrics are attached to the frame according to the structure of an umbrella. be able to. However, it is necessary to determine the shape of the wing bone so that it forms a paraboloid of revolution when the parabolic antenna is opened.

Further, in order to better maintain the paraboloid of revolution, it is preferable that the number of wing bones be as large as possible without making the parabolic antenna heavier, and usually about 16 wings are provided.

Also, different from a normal umbrella, the tip of the central axis, that is, the tip of the convex side of the paraboloid of revolution, can be made long so that the tip can be installed directly on the ground or via an installation member. good. Any rigid material may be used for the frame, but stainless steel is preferably used in consideration of durability.

Since the foldable parabolic antenna of the present invention uses a conductive fabric as a reflector, it is light and foldable, making it easy to store and change the installation position. In addition, by using conductive fabric with high air permeability, it is possible to make a parabolic antenna durable against wind when in use. This means that radio wave collection performance can be improved.

<Example> The configuration of the foldable parabolic antenna of the present invention will be explained below with reference to the attached drawings showing an embodiment of the foldable parabolic antenna of the present invention, and then several examples of hanging with conductive cloth will be described. Let me explain in detail.

FIG. 1 is a perspective view showing an embodiment of the foldable parabolic antenna of the present invention in an open state, and FIG. 2 is a longitudinal sectional view showing an embodiment of the folding parabolic antenna in a folded state.

The foldable parabolic antenna 1 of the present invention consists of a frame 10 and a conductive fabric 20. The frame 10 is rotatably supported on a central axis 11 and a joint 15 fixed at one point on the central axis 10, and is slidable on a plurality of wing bones 12, each having a parabolic shape, on the central axis 10. It consists of an attached bracket 13 and a plurality of push-up bones 14 that connect the bracket 13 and approximately the central portion of each wing bone 12. The structure of the frame 10 is similar to that of a normal umbrella. In the embodiment shown in FIG. 1, the lower right end 118 of the central axis 10 in FIG. Helps install the antenna directly on the ground or via mounting equipment.

However, the parabolic antenna may be installed using other installation tools without providing the end portion 11a.

The number of wing bones 12 is actually greater than that shown. The four-conductor fabric 20 is attached to the wing bone 12 using thread, strong adhesive, or other means such that when the parabolic antenna is opened, y! , a paraboloid of revolution is formed by the entire electrically conductive fabric 2o.

As shown in FIG. 2, the parabolic antenna can be folded by sliding the placket 13, and the entire parabolic antenna can be reduced in capacity when stored or transported.

In the illustrated example, the 411 cloth suspension 20 is attached to the outside of the frame 10, but it may be attached to the inside of the wing bone 12 from the functional aspect of the parabolic antenna. However, in that case, it is practically necessary to attach the push-up ribs 14 after attaching the quadrielectric fabric 20 to the wing bones 12.

Next, several examples of the electrocardiographic fabric used in the foldable parabolic antenna of the present invention will be described while comparing them with comparative examples.

The electromagnetic shielding effect used for the performance value was measured as follows. In other words, 30X with 3 aluminum plates
An oscillator was adjusted to a predetermined frequency of 12 GHz and placed in a 30×30 Crn box.

The lid was covered with a cloth or an aluminum plate, and the radio waves emitted from the oscillator were passed through a detector and measured with a microwave power meter.

The radio waves from the oscillator with the fabric etc. removed were also measured in the same way, and the ratio of power depending on the presence or absence of the fabric etc. in the sample box was expressed in dB as the electromagnetic shielding effect.

Further, the porosity v(1) of the fabric was calculated using the following formula.

Or the specific gravity of the yarn Q: The production conditions of Example 1 were woven using a 0.05φ Ninkle metal ## on a 32 gauge/1 inch Russell machine. The knitting conditions at this time were to use two reeds, a front reed and a back reed, and a 1 in, 2 out yarn arrangement, and the knitting structure at that time was 7 o 7 to 1 reed.
0/12/34/21, back reed 45/43/21/3
This is the arrangement of 4.

O Manufacturing conditions of Example 2 Polyester 15 was produced using the same knitting structure and same knitting machine as Example 1.
It was knitted using 0 denier 48 filament yarn.

The obtained fabric was vacuum-deposited using aluminum, and the deposition time was 60 minutes, and a film thickness of 1 was applied to each yarn.
．． A 5 μm aluminum layer was formed.

0 Manufacturing conditions of Example 3 Same knitting structure as Example 1, same - silky and polyester 15
The fabric was knitted using a 0 denier 48 filament yarn, and the resulting fabric/iK was chemically plated under the following conditions. That is, the fabric is immersed in a 10% sodium hydroxide solution at 80°C for 60 minutes, then neutralized with acetic acid and dried at 50°C for 10 minutes. Next, it is immersed in a solution containing 102 cc of stannous chloride and 30 cc of hydrochloric acid in 14 water at 35°C for 5 minutes, and then washed with water. Next, it was immersed in a solution containing 12 cc of chlorinated baladium sails and 1 cc of hydrochloric acid in 14 water at 40°C for 5 minutes, and then washed with water. Next, 251 parts of nickel chloride, 302 parts of sodium hypophosphite, and 15 parts of sodium acetate per 1 ton of water? 3 minutes at 80°C, then washed with water at 60°Csl.
A fabric chemically plated with nickel was obtained by drying C51O.

0 Production conditions of Example 4 A polymer prepared by adding aluminum powder with a particle size of 5 μm to polyurethane in a weight of 15φ based on the solid content of polyurethane on a knitted cloth (before vacuum deposition) obtained in the same manner as in Example 2. It was dried and coagulated at 1300C.

Manufacturing conditions for Example 5 A knitted fabric (before X-vacuum deposition) obtained in the same manner as in Example 2 was coated with a commercially available Niracle type '4 electrical paint. The coating amount at this time was 6°2/m2.

0 Manufacturing conditions of Example 6 A polyester 250 denier 50 filament yarn is wrapped with foil @ 0.3 gates and copper wire with a foil thickness of 0.025 ars at 2200 T/M using a covering machine, and the same knitting as in Example 1 is carried out. I made a knitted cloth according to the conditions.

0 Manufacturing Conditions of Comparative Example 1 Comparative Example 1 was prepared by mirror-finishing the surface of an aluminum plate with a thickness of 2-.

The electromagnetic shielding effect and other properties of each sample of Examples 1 to 6 and Comparative Example 1 were measured, and the results are shown in Table 1.

It can be seen that Examples 1, 2, 3 and 6 (see Table 1 below) have a practical electromagnetic shielding effect on a dB basis, although they are inferior. Examples 4 and 5 show that the electromagnetic shielding effect is somewhat poor, and that a parabolic antenna using such a fabric needs to have a larger diameter.

In addition, when comparing the basis weight, the fabric of Example is comparative example I (thickness 2
The weight of the parabolic antenna of the present invention is 1/10 to 1/4.5 compared to the size of the aluminum plate used in real parabolic antennas. It turns out that it is possible to reduce the Furthermore, the fabric of the example has better air permeability than an aluminum plate, as can be estimated from the numerical value of the porosity, so it is useful for making a parabolic antenna that is durable against wind.

<Effects of the Invention> Since the parabolic antenna of the present invention is constructed as described above, it is light and foldable, and as a result, it is easy to move and store, and has radio wave reflection properties that are sufficiently practical. . Moreover, no special means are required for its manufacture, and therefore it can be provided at a lower cost than conventional parabolic antennas made of metal plates.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of the foldable parabolic antenna of the present invention in an open state, and FIG. 2 is a longitudinal sectional view showing the foldable parabolic antenna shown in FIG. 1 in a folded state. be. 1... Foldable parabolic antenna, 10... Frame,
20... Conductive fabric.

Claims (1)

[Claims] 1. A central axis, a plurality of wing bones rotatably supported at one point of the central axis, a bracket slidably attached to the central axis, the bracket and the A foldable parabolic antenna configured to include a foldable frame consisting of a plurality of push-up bones connecting each of the plurality of wing bones, and a sheet-like material supported by the wing bones and covering between the wing bones. A folding parabolic antenna, characterized in that the shape of the wing bones is determined so as to form a paraboloid of revolution when the parabolic antenna is opened, and the sheet-like material is made of conductive fabric. 2. The folding parabolic antenna according to claim 1, wherein the conductive fabric has an electromagnetic wave shielding property of 20 dB or more in an electromagnetic wave frequency range of 12 GHz.