JP2600023B2 - Antenna device with reflector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna device equipped with a reflector in which a reflector used for a radio telescope or the like is supported on a mount.

[0002]

2. Description of the Related Art FIG. 4 shows a conventional antenna device with a reflecting mirror, wherein FIG. 4A is a plan view and FIG. Reference numeral 1 denotes a reflecting mirror having a honeycomb sandwich structure made of a composite material, which is symmetrical with respect to a central axis. Reference numeral 2 denotes a sub-reflection mirror, and reference numeral 3 denotes a plurality of support rods for fixing a metal fitting 4 screwed to an embedding metal 5 fixed to the reflection mirror 1, and is made of a composite material. Reference numeral 6 denotes a mount made of a metal material such as an iron material or an aluminum material. Reference numeral 7 denotes a support center ring supported on the mount 6 and made of a composite material. The reflecting mirror 1 and the support center ring 7 are joined together with an adhesive by rivets (not shown) by L-shaped fittings 9. 8 is composed of a composite material, and together with the adhesive, L
A support plate joined by rivets (not shown) by a metal fitting 10, and is mounted on the gantry 6 by bolt means or the like. Reference numeral 11 denotes a plurality of reinforcing rods connected to the vicinity of the embedded metal 5 of the reflecting mirror 1 and the support center ring 7 by an adhesive and a rivet (not shown). The composite material of the reflector 1, the support rod 3, the support center ring 7, the support plate 8, and the reinforcing rod 11 is, for example, CFR.
It is made of P (Carbon Fiber Reinforced Plastic). w indicates a radio wave path from the outside.

Next, the operation will be described. Radio waves from the outside are primarily reflected by the reflecting mirror 1 and secondarily reflected by the sub-reflecting mirror 2 along the radio wave path w, and pass through the inside of the gantry 6 to reach a receiver (not shown). Thereby, radio wave observation is performed.

Since the reflector 1, the support rod 3, the support center ring 7, the support plate 8 and the reinforcing rod 11 are made of a composite material having a small linear expansion coefficient, thermal deformation due to solar radiation or a change in ambient temperature is small. Therefore, the amount of shape change due to thermal deformation of the surface of the reflecting mirror 1 coupled to these members is small. This reduces the amount of gain reduction due to a change in the shape of the reflecting mirror 1 due to changes in solar radiation and ambient temperature.

However, although the amount of thermal deformation of the reflecting mirror 1 itself is small, the amount of thermal deformation of the gantry 6 made of a metal material is large, so that the reflecting mirror 1 is deformed. For this reason, as shown by the chain line in FIG. 5, the amount of change in the shape of the surface of the reflecting mirror 1 increases.

[0006]

In the conventional antenna device with a reflector as described above, the reflector 1 is deformed due to the large thermal deformation of the gantry 6, the amount of change in the shape of the surface is increased, and the gain is reduced. There was a problem that it decreased.

The present invention has been made in order to solve such a problem. Even in the case where the temperature of the gantry is different from that of the reflecting mirror, the amount of thermal deformation due to the difference in the coefficient of linear expansion between the gantry and the reflecting mirror can be improved even when the temperature of the sun or the atmosphere changes. It is an object of the present invention to obtain a reflector-equipped antenna device in which the amount of change in the shape of the reflector is reduced.

[0008]

An antenna device with a reflector according to the present invention supports the reflector on a metal gantry.
In the thing, the large-diameter part of the truncated cone-shaped shell made of the composite material having a thinner structure than the reflection boundary is joined to the back surface of the composite material sandwich structure reflection mirror, and on the radial tangent of the back surface of the reflection boundary, This is one in which the conical inclined surfaces of the shell are almost matched, and the small diameter portion of the shell is connected to the upper side of the gantry.

In the first invention, the shell is made thinner and has a lower bending rigidity than the reflecting mirror.

According to the second invention, the trapezoidal trapezoidal shell has a honeycomb sandwich structure made of a composite material, and the large diameter portion of the shell is connected to the back surface of the reflecting mirror by a plurality of pin connecting means.

[0011]

In the present invention, since the shell has a thin-walled or honeycomb sandwich structure, the bending rigidity is lower than that of the reflecting mirror. And the influence on the reflecting mirror is prevented.

Further, the conical inclined surface of the shell almost coincides with the tangent in the radial direction of the back surface of the reflecting mirror, and the force transmitted from the shell to the reflecting mirror due to thermal deformation or the like is generated by the in-plane directional force of the reflecting mirror. Therefore, the reflecting mirror is not greatly deformed.

[0013]

FIG. 1 shows an embodiment of an antenna device with a reflector according to the present invention. FIG. 1A is a plan view, FIG. 1B is a front view of a half section, and FIGS. The same is true. twenty one
Is a shell formed of a composite material (for example, CFRP) having a small linear expansion coefficient and formed in a conical trapezoid thinner than the reflecting mirror 1, and a large diameter portion is provided with an adhesive and a number of rivets (not shown) on the back surface of the reflecting mirror 1. And are joined by In this joint, a shell 21 is provided on the tangent in the radial direction of the back surface of the reflecting mirror 1.
Are made to almost coincide with each other. Reference numeral 22 denotes a support plate made of a composite material, which is connected to a small diameter portion of the shell 21 by an adhesive and a rivet (not shown), and is mounted on the gantry 6 by bolt means (not shown).

Next, the operation will be described. The reflecting mirror 1, the support rod 3, the shell 21 and the support plate 22 are made of a composite material having a small coefficient of linear expansion, and have a small thermal deformation due to solar radiation or a change in ambient temperature. On the other hand, the gantry 6 made of a metal material undergoes greater thermal deformation than the reflecting mirror 1 and the shell 21.

For this reason, as shown in FIG.
, A tensile and compressive force T is applied, and a bending moment M is generated. Since the reflector 1 has a sandwich structure made of a composite material and the shell 21 has a thin-walled structure made of a composite material, in many cases, the bending rigidity of the former is more than 100 times larger than that of the latter. Thereby, when the bending moment M is generated, the shell 21
2B, the deformation angle of the reflecting mirror 1 is 1/100 or less of that of the shell 21.

Further, the tensile and compressive forces T are transmitted from the shell 21 to the reflecting mirror 1, but since the tangential directions are substantially coincident with each other at the joints thereof, they are transmitted to the reflecting mirror 1 as an in-plane force and as an out-of-plane force. Is not transmitted. The degree of deformation of the reflecting mirror 1 is very small in the in-plane force as compared with the out-of-plane force.

FIG. 3 is a front view of a second embodiment of a reflector-equipped antenna device according to the present invention, in which one half is sectioned. Reference numeral 23 denotes a honeycomb sandwich structure of a composite material, which is a conical trapezoidal shell. The small diameter part of the shell 23 is a support plate
22 and a rivet (not shown) by an L-shaped bracket 10 together with an adhesive. The support plate 22 is mounted on the gantry 6 by bolt means (not shown). The shell 23 is joined to and supported on the back surface of the reflecting mirror 1 by a large number of pin joining means 24 at a large diameter portion. In this joint portion, the conical inclined surface of the shell 23 almost coincides with the radial tangent of the back surface of the reflecting mirror 1. Pin coupling means 24
Comprises a metal fitting 26 joined to the shell 23, a metal fitting 25 joined to the reflecting mirror 1, and a coupling pin 27 passed through these metal fittings. The bending rigidity of the shell 23 is smaller than that of the reflecting mirror 1.

In the second embodiment, when the gantry 6, the reflecting mirror 1, and the shell 23 have different amounts of deformation, a bending moment and tensile / compression forces are generated in the shell 23. When a bending moment is generated, the shell 23 is rotatably connected to the reflecting mirror 1 by the pin connecting means 24, so that the reflecting mirror 1 does not transmit the bending moment and does not deform. When a tensile / compressive force is generated, the force is applied to the reflecting mirror 1. However, since the two tangential directions almost coincide with each other at the joint portion, the tangential direction is transmitted to the reflecting mirror 1 as an in-plane force. Will be very small.

[0019]

As described above, according to the present invention, the bending rigidity ratio is set to 1 by making the structure of the composite material thinner than the reflection boundary.
A conical trapezoidal shell larger than 00: 1 couples the large-diameter portion to the back surface of the reflecting mirror, makes the conical inclined surface of the shell substantially coincide with the radial tangent of the back surface of the reflecting mirror, and reduces the small-diameter portion to metal. since bound to the frame above the manufacturing, even if the thermal deformation of the metal frame is increased, the tensile and compression forces from the shell act deformation is small as plane force to the reflecting mirror.

Further, in the first invention, since the shell is made thin, when the thermal deformation of the gantry becomes large, the shell absorbs the bending moment by elastic deformation, and the reflecting mirror is not affected.

Further, in the second invention, the shell has a honeycomb sandwich structure, and the large-diameter portion is connected to the back surface of the reflecting mirror through a large number of pin connecting means. Occurs, the pin mirror is released by the interposition of the pin coupling means, and the deformation of the reflecting mirror becomes extremely small.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a reflector antenna device according to the present invention, wherein FIG. 1A is a plan view and FIG. 1B is a front view of a half section.

FIG. 2A is an explanatory view showing a force applied to a shell due to a difference in thermal expansion between a gantry and a reflecting mirror in FIG. 1B, and FIG. 2B is an explanatory view showing deformation of a shell due to thermal deformation of the gantry in FIG. 1B.

FIG. 3 shows a second embodiment of the antenna device with a reflector according to the present invention.
It is the front view which carried out the cross section of one half which shows the Example of this.

4A and 4B show a conventional antenna device with a reflector, wherein FIG. 4A is a plan view and FIG. 4B is a front view of a half section.

FIG. 5 is an explanatory view showing deformation of a support center ring and a reflecting mirror due to thermal deformation of the gantry of FIG. 4;

[Explanation of symbols]

1 Reflector, 6 stand, 21 shell, 22 support plate, 23
Shell, 24 pin coupling means.

Claims (2)

(57) [Claims] 1. A reflecting mirror is supported on a base made of a metal material.
In shall, be in composite sandwich structure, a reflecting mirror symmetrical shape to the central axis, without the frustoconical is thinner structure than the reflection mirror of a composite material, radially on the rear surface of the reflecting mirror in the large diameter portion So that the tangent directions of
Connect the shell to be joined and supported and the small diameter
It has a support plate made of composite material, which is fixed on a metal base.
An antenna device with a reflecting mirror. 2. A reflecting mirror is supported on a base made of a metal material.
In the above, a composite material sandwich structure and a reflecting mirror having a shape symmetrical with respect to the central axis, and a honeycomb sandwich structure of a composite material forming a truncated cone and a tangent in a radial direction to the back surface of the reflecting mirror at a large diameter portion Directions almost match
And the small diameter part of this shell
A support made of a composite material, which fixes the above on the metal base
An antenna device with a reflector, comprising a plate .