JPH11234034A - Extensible antenna reflector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease the number of mobile parts for improvement of the extension reliability by attaching a mirror surface holding structure to an extension mechanism and also to prevent damages, sticking and entanglement of metallic meshes and cables by holding these meshes and cables with proper pressing force. SOLUTION: A mirror surface holding structure 5 are attached to the extension mechanisms 3 to press the meshes 1 and cables 2 for preventing them from being tangled or freely moving around against the vibrations which are caused when its reflector is launched. On a track, the explosion tubes of the holding release mechanisms 7 which are restraining the mechanisms 3 operate to release the restraint of mechanisms 3. Then the mechanism 3 and the structures 5 attached to the mechanisms 3 extend in the directions (a) to stretch and hold the meshes 1 and cables 2 by the extending force of mechanism 3. According to this constitution, both mechanisms 3 and structures 5 extend by the extending force of mechanisms 3 to omit the holding release/extension mechanism of every structure 5 itself.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deployable antenna reflector mounted on an artificial satellite or the like.

[0002]

2. Description of the Related Art Antenna reflectors mounted on artificial satellites and the like have been required to be larger with the expansion of space use. However, due to the limited storage space for launch vehicles, they have been folded small. An antenna system that is deployed on a launch orbit in a state is being studied. FIG. 6 (a),
FIG. 6B shows an example of a deployable antenna reflector that has been studied in the related art. FIG. 6A is a view showing an antenna storage state, and FIG. 6B is a view showing an antenna deployment state. is there. In the figure, reference numeral 1 denotes a metal mesh constituting a radio wave reflecting surface of an antenna, 2 denotes a plurality of cables that retain the shape of the metal mesh 1, and 3 denotes a metal mesh 1 and a cable 2 which are unfolded and stored from a stored state. Is a deployment mechanism that stretches and holds them, 4 is a metal mesh 1, a cable 2, a center hub that positions and fixes the deployment mechanism 3 in a predetermined position, 5 is attached to the center hub 4, and the metal mesh 1 and the A mirror holding structure for holding down the cable 2, a holding structure deploying hinge 6 for deploying the mirror holding structure 5, a restraining mechanism 7 for holding the deployment mechanism 3 and the mirror holding structure 5 in an antenna housed state, and releasing the restraint on the track. Holding and releasing mechanism.

At the time of launching, as shown in FIG. 6 (a), the metal mesh 1 and the cable 2 are held down by the mirror surface holding structure 5 so that they do not become entangled or move around freely due to vibrations at the time of launching. Regarding the behavior of the mirror surface, since the amount of data accumulated so far may be small, only the mirror surface holding structure 5 is held at a predetermined position so that the entire metal mesh 1 and the cable 2 can be pressed down evenly. Such a method was taken. On the orbit, first, the holding and releasing mechanism 7 that restrains the mirror surface holding structure 5
, And releases the restraint of the mirror surface holding structure 5. Subsequently, the mirror surface holding structure 5 is expanded in the direction of A by the expanding force of the holding structure expanding hinge 6, and the holding of the metal mesh 1 and the cable 2 is released. After that, the explosion tube of the holding and releasing mechanism 7 that restrains the deployment mechanism 3 operates to release the restraint of the deployment mechanism 3. Finally, the deploying mechanism 3 deploys in the direction of A, and stretches and holds the metal mesh 1 and the cable 2 as shown in FIG. A spiral spring, a motor, or the like is used as a drive source of the holding structure deployment hinge 6 and the deployment mechanism 3.

Conventionally, the holding / release of the metal mesh 1 and the cable 2 is performed by the holding / releasing mechanism 7 and the holding structure deploying hinge 6 as described above for the purpose of simplifying each function / configuration of the movable portion and improving deployment reliability. Then, a method has been adopted in which the stretching and holding of the metal mesh 1 and the cable 2 are separately performed by the deployment mechanism 3. Therefore, the mirror holding structure 5 and the holding structure deployment hinges 6 are required in the same number as the deployment mechanism 3, and the holding / releasing mechanisms 7 are required in the same number as the mirror holding structure 5 and the deployment mechanism 3.

[0005]

However, in order to increase the deployment reliability, it is desirable that the number of movable parts is small. On the other hand, when the mirror holding structure 5 is provided for the purpose of preventing the mirror from being entangled, the holding and releasing mechanism is required. 7 and the holding structure deployment hinge 6 are also required, and there is a contradictory problem that the number of movable parts increases. The required number of the unfolding mechanisms 3 is determined mainly by the mirror accuracy / mirror rigidity, etc.
In order to achieve a highly rigid mirror surface, the number of deployment mechanisms 3 may be increased. However, the arrangement space of the holding / releasing mechanism 7 and the holding structure deployment hinge 6 must be considered. There is a problem that the shapes of the holding release mechanism 7 and the holding structure deploying hinge 6 are complicated, and the deploying reliability is reduced.

When the metal mesh 1 and the cable 2 are pressed by the mirror surface holding structure 5, if the metal mesh 1 and the cable 2 are pressed too much, the metal mesh 1 and the cable 2 may be damaged or fixed. It becomes easily entangled during deployment by tangling or freely moving around due to vibration, and in any case, it is very likely to be fatal to the antenna, and it is very important whether or not it can be held down with an appropriate pressing force However, conventionally, the metal mesh 1 and the cable 2 could only be pressed down at predetermined positions. However, since the metal mesh 1 and the cable 2 are soft, the metal mesh 1 and the cable 2 are not always reproduced in a fixed shape every time they are completely unfolded / stored. If the metal mesh 1 and the cable 2 can be pressed only at a predetermined position, the pressing force is not uniform. There is a problem that there is a possibility of causing a problem. Further, since there is no means for monitoring how much pressing force the mirror surface holding structure 5 presses the metal mesh 1 and the cable 2, there is a problem that the pressing position of the mirror surface holding structure 5 can only be set empirically. there were.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. The present invention has been made to reduce the number of movable parts to increase the deployment reliability and to hold the metal mesh 1 and the cable 2 with an appropriate pressing force. It is an object of the present invention to obtain a deployable antenna reflector that can prevent damage, sticking and entanglement.

[0008]

The deployable antenna reflector according to the first aspect of the present invention eliminates the holding release mechanism and the holding structure deploying hinge required for the mirror holding structure, and attaches the mirror holding structure to the deploying mechanism. The holding mechanism releases the holding of the metal mesh and the cable when the spreading mechanism is expanded.

Further, in the deployable antenna reflector according to the second aspect of the present invention, a surface pressure sensing sheet is provided on the metal mesh and the cable contact surface side of the mirror surface holding structure so that the pressing force distribution of the mirror surface holding structure can be monitored. Things.

Further, in the deployable antenna reflector according to the third aspect of the present invention, the cushioning material is provided on the metal mesh and the cable contact surface side of the mirror surface holding structure, and the pressing force of the mirror surface holding structure is locally increased or reduced. Is prevented.

Further, in the deployable antenna reflector according to the fourth aspect of the present invention, the mirror holding structure is provided with a mirror holding force adjusting mechanism so that the pressing force of the metal mesh and the cable can be adjusted.

Further, in the deployable antenna reflector according to the fifth aspect of the invention, a coil spring is provided in the mirror surface holding force adjusting mechanism so that the pressing force applied to the metal mesh and the cable can be adjusted while monitoring the amount of extension of the coil spring. It was done.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a view showing a first embodiment of the present invention. FIG. 1A shows an antenna housed state, and FIG. 1B shows an antenna deployed state. In the figure, reference numerals 1 to 4 are the same as those of the above-mentioned conventional deployable antenna reflector, and the description thereof is omitted. 5 is attached to the unfolding mechanism 3, and the metal mesh 1
And a mirror holding structure 7 for holding down the cable 2, and a holding / releasing mechanism 7 for holding the deployment mechanism 3 in the antenna housed state and releasing the restraint on the track. At the time of launching, as shown in FIG. 1A, the metal mesh 1 and the cable 2 are held down by the mirror surface holding structure 5 so as not to be entangled or move around freely due to the vibration at the time of launching. On the orbit, the squib of the holding and releasing mechanism 7 that restrains the deployment mechanism 3 operates to release the restraint of the deployment mechanism 3. Thereafter, the deployment force of the deployment mechanism 3 causes the deployment mechanism 3 and the mirror surface holding structure 5 attached to the deployment mechanism 3 to deploy in the direction of A, and stretches the metal mesh 1 and the cable 2 as shown in FIG. ·Hold. Since the mirror holding structure 5 is also unfolded by the unfolding of the unfolding mechanism 3, the functions / configurations of the movable portion remain the same as in the related art, and the mirror holding structure 5 itself required by the conventional deployable antenna reflector is held. A mechanism movable part for release / deployment becomes unnecessary, and deployment reliability can be increased.

Embodiment 2 FIG. FIG. 2 is a view showing a second embodiment of the present invention, in which a portion around a mirror surface holding structure 5 is partially enlarged. Reference numeral 8 denotes a surface pressure sensing sheet provided on the contact surface side of the metal mesh 1 and the cable 2 of the mirror surface holding structure 5, for example, a pressure-sensitive paper that changes color according to the magnitude of the surface pressure, or a sheet on which a number of thin pressure sensors are arranged It is composed of When the surface pressure sensing sheet 8 is made of pressure-sensitive paper, the antenna is completely housed with the surface pressure sensing sheet 8 attached, and then the antenna is deployed to a position where the surface pressure sensing sheet 8 can be seen. See the discolored state of. Since the discoloration of the surface pressure sensing sheet 8 increases in proportion to the magnitude of the pressing force, the distribution of the pressing force can be confirmed by checking the discoloration state of the surface pressure sensing sheet 8. . If the pressing force non-uniformity is within the allowable range, the surface pressure sensing sheet 8 is removed, the antenna is stored as it is, and the antenna storing operation on the ground is completed. If the pressing force non-uniformity is out of the allowable range, correct the storage shape of the metal mesh 1 and the cable 2 and replace the surface pressure sensing sheet 8 until the pressing force non-uniformity falls within the allowable range. repeat. When the surface pressure sensing sheet 8 is constituted by a sheet in which a number of thin pressure sensors are arranged, the output lines from the individual thin pressure sensors are connected to measuring devices, respectively, and are proportional to the pressing force applied to the thin pressure sensors. By monitoring the fluctuating voltage, the distribution of the pressing force can be confirmed. Except that the pressing force can be monitored with the antenna housed and that the surface pressure sensing sheet 8 does not need to be replaced, the non-uniformity of the pressing force is kept within an allowable range in the same procedure as when the pressure-sensitive paper is used. The antenna storage operation on the ground can be terminated in the state where the antenna is stored. By using the surface pressure sensing sheet 8,
Non-uniformity of the pressing force applied to the metal mesh 1 and the cable 2 can be reduced, and damage, fixation and entanglement of the mirror surface can be prevented.

Embodiment 3 3A and 3B show a third embodiment of the present invention. FIG. 3A shows a partially enlarged view around a mirror surface holding structure 5, and FIG. 3B shows a metal mesh in an antenna housed state. 1 shows a partial cross section of a state of the cable 1 and the cable 2. Numeral 9 is a cushioning material attached to the metal mesh 1 and the cable 2 contact side of the mirror surface holding structure 5 and is made of a viscoelastic material such as polyurethane foam or closed cell foam. Reference numeral 10 denotes a cable connecting member for connecting the plurality of cables 2 and is made of, for example, a metal or a polymer material. If the volume of the cable connecting member 10 is large, only the cable connecting member 10 locally protrudes as compared with the metal mesh 1 and the cable 2 when the antenna is housed. If the pressing is performed by the mirror holding structure 5 in this state, a large pressing force is applied only to the cable connecting member 10 and no pressing force is applied to the metal mesh 1 and the cable 2. By sticking, it is possible to prevent a large pressing force from being applied due to the deformation of the cushion material 9 in the portion of the cable connecting member 10, and to press the entire mirror surface with a uniform pressing force, thereby preventing damage and fixation of the mirror surface. The cushion material 9 is attached to the entire surface of the mirror surface holding structure 5 on the contact surface of the metal mesh 1 and the cable 2 or, if the position of the projecting portion of the cable connecting member 10 or the like is limited in advance, to the portion only. Thus, the mirror surface can be prevented from being damaged and fixed as described above.

Embodiment 4 FIG. 4 is a view showing a fourth embodiment of the present invention. FIG. 4 (a) shows a state in which the antenna is housed, and FIG. 4 (b) is a partially enlarged view of the mirror holding structure 5. Numeral 11 connects the unfolding mechanism 3 and the mirror-surface holding structure 5 and strokes in the direction of B.
This is a mirror holding force adjusting mechanism capable of adjusting a relative positional relationship between the mirror holding structure 5 and the mirror holding structure 5. The mirror holding force adjusting mechanism 11 has three sets of the unfolding mechanism 3 and the mirror holding structure 5.
It is configured such that it can be separately mounted at four places or four places and can be manually stroked independently in the direction of B. After the antenna is housed and the deployment mechanism 3 is restrained by the holding and releasing mechanism 7, the metal mesh 1 and the cable 2 are adjusted by adjusting the mirror holding force adjusting mechanisms 11 according to the storage shapes of the mirror mesh 1 and the cable 2. The pressing force applied to the mirror surface can be appropriately set to prevent the mirror surface from being damaged, fixed and entangled. The adjustment of the mirror holding force adjusting mechanism 11 is performed by using a stroke portion of the mirror holding force adjusting mechanism 11 attached to the mirror holding structure 5 side with respect to a fixed portion of the mirror holding force adjusting mechanism 11 attached to the deployment mechanism 3 side. It is performed by shifting in the direction of b. The fixed part and the stroke part of the mirror surface holding force adjusting mechanism 11 are connected by, for example, a combination of bolts and nuts. When performing the adjustment, loosen the bolts and nuts so that the stroke is possible. / Tighten the nut to fix.

Embodiment 5 FIG. 5 is a view showing a fifth embodiment of the present invention, in which the mirror holding structure 5 is partially enlarged. Reference numeral 12 denotes a coil spring mounted between the fixed portion and the stroke portion of the mirror surface holding force adjusting mechanism 11 and having a predetermined spring constant. When the antenna is housed in a state where the connection between the fixed portion and the stroke portion of the mirror holding force adjusting mechanism 11 is loosened and the deployment mechanism 3 is fixed by the holding and releasing mechanism 7, the pressing reaction force from the mirror mesh 1 and the cable 2 and the coil Until the spring force of the spring 12 is balanced, the mirror holding force adjustment mechanism 11 strokes in the direction B, and the relative positions of the deployment mechanism 3 and the mirror holding structure 5 are shifted.
At this time, one set of the unfolding mechanism 3/3
By measuring the amount of extension of the coil spring 12 using calipers or the like with respect to each of the mirror surface holding force adjusting mechanisms 11 dispersedly mounted at four or four locations, the magnitude / variation of the pressing force is quantitatively determined. Monitor. If the magnitude / variation of the pressing force is within the allowable range, the fixed portion and the stroke portion of the mirror holding force adjustment mechanism 11 are fixed as they are. If the magnitude / variation of the pressing force is out of the permissible range, the mirror holding structure 5 is pushed in the direction of pressing the mirror holding structure 5 toward the mirror surface for a portion where the holding force is desired to be increased, and the mirror holding structure 5 is pushed in the mirror surface for the portion where the holding force is desired to be reduced. When the pressing force falls within the allowable range, the fixed portion and the stroke portion of the mirror surface holding force adjusting mechanism 11 are fixed. By quantitatively controlling the magnitude / variation of the pressing force applied to the metal mesh 1 and the cable 2 as described above, it is possible to prevent the mirror surface from being damaged, fixed and entangled.

[0018]

According to the first aspect of the present invention, the mirror holding structure is attached to the expanding mechanism, and the mirror holding structure is also expanded by expanding the expanding mechanism. Since a mechanism is not required, the number of movable parts can be reduced, and deployment reliability can be improved.

According to the second aspect of the present invention, since the surface pressure sensing sheet is provided on the metal mesh and cable contact side of the mirror holding structure, the distribution of the pressing force applied to the metal mesh and the cable when the antenna is housed is monitored. be able to. Therefore, the folding of the metal mesh and the cable is changed again according to the distribution, the metal mesh and the cable can be held with a uniform pressing force, and the mirror surface can be prevented from being damaged, fixed and entangled.

According to the third aspect of the present invention, even when the cable connecting member for connecting the cables occupies a large volume, the cushion material is deformed to apply a large pressing force locally to the portion. To prevent the mirror surface from being damaged or fixed.

According to the fourth aspect of the present invention, the pressing position of the mirror holding structure is adjusted by using the mirror holding force adjusting mechanism according to the storage shape, so that even when the storage shape reproducibility is poor, the metal mesh and the metal mesh can be used. The cable can be held with an appropriate pressing force, and damage, fixation and entanglement of the mirror surface can be prevented.

According to the fifth aspect of the present invention, the mirror holding force adjusting mechanism is used while monitoring the pressing force applied to the metal mesh and the cable based on the extension of the coil spring to which the mirror holding force adjusting mechanism is attached. By adjusting the pressing position of the mirror surface holding structure, even if the mirror surface is easily damaged and fine adjustment of the pressing force is required, the metal mesh and cable can be held with an appropriate pressing force, preventing damage, fixation and entanglement of the mirror surface be able to.

[Brief description of the drawings]

FIG. 1 is a diagram showing a deployed antenna reflector according to a first embodiment of the present invention;

FIG. 2 is a diagram showing a deployed antenna reflector according to a second embodiment of the present invention;

FIG. 3 is a diagram showing a deployed antenna reflector according to a third embodiment of the present invention;

FIG. 4 is a diagram showing a deployed antenna reflector according to a fourth embodiment of the present invention;

FIG. 5 is a diagram showing a fifth embodiment of the deployable antenna reflector according to the present invention;

FIG. 6 is a diagram showing a conventional deployable antenna reflector.

[Explanation of symbols]

1 metal mesh, 2 cables, 3 deployment mechanism, 4
Center hub, 5 mirror surface holding structure, 6 holding structure deployment hinge, 7 holding release mechanism, 8 surface pressure sensing sheet, 9 cushion material, 10 cable connecting member, 11 mirror surface holding force adjusting mechanism, 12 coil spring.

Claims (5)

[Claims] 1. A metal mesh forming a radio wave reflecting surface of an antenna, a plurality of cables retaining the shape of the metal mesh, and a metal mesh and the cable are unfolded from a stored state. A deployment mechanism for stretching and holding, a center hub for arranging and fixing the metal mesh, the cable, and the deployment mechanism at a predetermined position, a mirror holding structure for holding down the metal mesh and the cable when launching the antenna, and a A deployable antenna reflector, comprising: the deployment mechanism, the mirror holding structure, and the deployment mechanism, and a holding release mechanism for releasing the mirror holding structure when the antenna is deployed on a track, wherein the mirror holding structure is provided by the deployment mechanism. A deployable antenna reflector, mounted on top. 2. The metal mesh of the mirror holding structure,
The deployable antenna reflector according to claim 1, wherein a surface pressure sensing sheet is provided on a contact surface with the cable. 3. The metal mesh of the mirror holding structure,
The deployable antenna reflector according to claim 1, wherein a cushion material is provided on a contact surface with the cable. 4. The deployable antenna reflector according to claim 1, wherein a mirror holding force adjusting mechanism is provided in said mirror holding structure. 5. The deployable antenna reflector according to claim 4, wherein a coil spring for adjusting a holding force is attached to said holding force adjusting mechanism.