JP4183074B2 - Unfolding structure holding and releasing mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mechanism for holding and releasing a deployment structure such as a solar battery paddle, a deployment radiator, and a deployment antenna of a spacecraft such as a spacecraft, an artificial satellite, and the like, and particularly mechanically restrains when the deployment structure is folded. The present invention relates to a holding and releasing mechanism for a deployment structure.
[0002]
[Prior art]
A conventional state in which a solar battery paddle of an artificial satellite, for example, is stored and held is as follows. The solar cell plates are stacked such that the front and back surfaces of adjacent solar cell plates are opposite to each other. These solar cell plates are connected to adjacent paddles by deployment hinges. The holding bush fixed to each solar cell plate is housed in a state of being fitted to the holding bush of the adjacent solar cell plate. Further, a rod-shaped holding member penetrating through the holding bush couples the solar cell plate and the satellite structure that are overlapped on top to hold the housing state. In such a storage state, the solar cell element mounted on the lower surface of the solar cell plate is stored in contact with the solar cell element mounted on the upper surface of the solar cell plate (see, for example, Patent Document 1).
[0003]
[Patent Document 1]
JP-A-10-147298 (lines 4-10 of paragraph 0015, and FIGS. 1-9)
[0004]
[Problems to be solved by the invention]
This conventional solar cell paddle is stored in the fairing of the rocket in a state of being folded by a number of holding and releasing mechanisms so as to withstand the environment when the rocket is launched. For this reason, a large number of holding and releasing mechanisms are arranged around a driving mechanism which is a connection point between the satellite structure and the solar battery paddle. The holding bushes to be fitted, that is, the bush pairs, of the holding and releasing mechanism mechanically restrain the entire satellite structure and the solar cell paddle. Among these bush pairs, in the interface part between the satellite structure and the solar cell paddle, which are easily affected by the difference in linear expansion coefficient, the bush pair engaged by the key and the key groove is in the middle of the front and rear and the middle of the top and bottom. Has been placed. In order to ease the processing accuracy of the developed structure, a pair of bushes that are engaged with each other on a flat surface are arranged on the diagonal line of the interface portion and inside the solar cell paddle.
[0005]
One of the bush pairs is provided with a pair of keys in the diameter direction, and the other is provided with a pair of key grooves in the diameter direction. In the interface unit, a line connecting the center of the key or key groove of the bush pair located in the middle of the front and rear is directed in the vertical direction, and a line connecting the center of the key or key groove of the bush pair positioned in the upper and lower center Is directed left and right. A relatively large clearance is provided between the key and the key groove to prevent the generation of thermal stress due to the difference in the linear expansion coefficient at the interface part, and the error in manufacturing the solar cell paddle is absorbed. Reliability is ensured that the battery paddle is deployed reliably.
[0006]
However, in recent years, the solar cell paddle has become larger and the weight of the solar cell paddle has increased with the increase in the size of the artificial satellite. For this reason, the holding force for holding the solar cell paddle in the folded state, that is, the holding load applied to the holding and releasing mechanism increases. On the other hand, there is a direct causal relationship between the holding load that holds the solar cell paddle in a folded state and the impact force that is generated when the solar cell paddle is deployed. That is, the impact force increases as the holding load increases, and this impact force adversely affects the equipment mounted on the satellite structure. Therefore, there is a limit in increasing the holding load applied to the holding and releasing mechanism. In addition, there is a limit to increasing the clearance between the key and the key groove from the viewpoint of securely holding the unfolded structure and unfolding it reliably.
[0007]
And since the key and keyway of the bush pair of the interface part are directed only in the vertical direction and the horizontal direction, the following problem occurs when the weight of the solar cell paddle increases. In other words, it becomes difficult to suppress the holding load, prevent the generation of thermal stress based on the difference in the linear expansion coefficient of the interface part, absorb the error in manufacturing the solar cell paddle, etc. It becomes difficult to configure a holding and releasing mechanism corresponding to the battery paddle.
[0008]
The present invention has been made to solve the above-described problems, and its purpose is to increase the mechanical restraint force on the deployed structure without increasing the holding load, and thus more than the conventional one. Further, a deployment structure holding and releasing mechanism capable of holding a heavy deployment structure is obtained.
[0009]
[Means for Solving the Problems]
In the spacecraft deployment structure holding and releasing mechanism according to the present invention, when the deployment structure is folded, the first bush pair is engaged by the key and the key groove, and the second bush pair is A line that is engaged by the annular convex portion and the annular concave portion and that connects the key or key groove of the first bush pair and the center of the bush is directed in a radial direction with respect to the drive mechanism. .
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
FIG. 1 shows a state in which a pair of solar cell paddles (deployment structures) 3 supported by a support structure 2 of a spacecraft 1 according to Embodiment 1 of the present invention is deployed. The pair of solar cell paddles 3 are connected to the left and right side surfaces 4 of the support structure 2, respectively. In the center of the side surface 4 of the support structure 2, a connecting portion 6 of a drive mechanism 5 that drives the solar cell paddle 3 to follow the sun is provided. Further, in the radial direction around the drive mechanism 5 on the side surface 4 of the support structure 2, for example, eight consoles 8 of the holding and releasing mechanism 7 for holding and releasing the solar cell paddle 3 in the folded position are provided. Yes. As for the direction used in the first embodiment, the direction of arrow F in FIG. 1 is “front”, and this “front” is used as a reference for other directions.
[0011]
In the solar cell paddle 3, a yoke 11 is connected to a connecting portion 6 of the drive mechanism 5 via a hinge 12. Further, for example, three panels 13 to 15 are connected to the yoke 11 via hinges 16 to 18, respectively. Thereby, the solar cell paddle 3 can be folded. Solar electronic elements (not shown) made up of a large number of cells are respectively mounted on one side of the panels 13 to 15 on the same side. The panels 13 to 15 are formed with through holes 19 for constituting the holding and releasing mechanism 7 corresponding to the holding and releasing mechanism 7, and bushes to be described later are attached to these through holes 19. It has become. The outermost panel 15 is connected to an outer end of a rod (not shown) that is tensioned by the holding and releasing mechanism 7 through the through hole 19. Further, the hinge 12 and the hinges 16 to 18 are provided with a biasing means such as a spring (not shown) for biasing the panels 13 to 15 to the deployed position.
[0012]
As shown in FIG. 2, when the solar cell paddle 3 is accommodated in the fairing of the rocket, the rod passed through the through hole 19 is pulled by the holding and releasing mechanism 7, and the yoke 11 and the panels 13 to 15 are biased. It is designed to fold against the urging force. Therefore, the solar cell paddle 3 according to the present invention can withstand all environments such as impact, acceleration, and temperature when launching a rocket, and can be reliably deployed after the spacecraft 1 reaches a predetermined orbit. ing.
[0013]
As shown in FIG. 3, the console 8 of the holding / releasing mechanism 7 has a truncated cone shape, for example. Inside the console 8, a rod tension means (not shown) that holds the solar cell paddle 3 in a folded state by pulling the rod, or the solar cell paddle 3 is released by cutting the rod when the solar cell paddle 3 is deployed. A rod cutting means is installed.
[0014]
The console 8 and the yoke 11 are provided with a plurality of first bushing pairs 21 and 22 that are engaged with each other when folded. The yoke 11 and the panels 13 to 15 are provided with a plurality of second bushing pairs 23 and 24 that engage with each other when they are folded. The first bushing pair 21 and 22 mechanically restrains the space between the support structure 2 and the yoke 11 and releases thermal stress. The second bushing pair 23, 24 is between the yoke 11 and the first panel 13, between the first panel 13 and the second panel 14, and between the second panel 14 and the third panel 15. Are to be mechanically restrained.
[0015]
That is, one bush 21 is fixed to the end surface of the console 8, and the other bush 22 fixed to the yoke 11 is engaged with the bush 21. One bush 23 is fixed to the upper surface of the yoke 11, the first panel 13, and the second panel 14, and the first panel 13, the second panel 14, and the third panel 15 are fixed to the bush 23. The other bush 24 fixed to the lower surface is engaged.
[0016]
As shown in FIG. 4, a pair of key grooves 31 are formed in the diameter direction on the upper surface of the bush 21. In addition, a pair of keys 32 that are respectively fitted in the key grooves 31 of the bush 21 are formed on the lower surface of the bush 22. A contact surface between the bush 21 and the bush 22 is provided with a fired film of a solid lubricant made of molybdenum disulfide or the like, or a sprayed film made of tungsten carbide. Thus, when the solar cell paddle 3 is deployed, the bush 21 and the bush 22 are not separated from each other and are easily separated from each other. In addition, a clearance is provided between the keyway 31 and the key 32 to securely hold and release the solar cell paddle 3. Thereby, it is possible to prevent the generation of thermal stress due to the difference in linear expansion coefficient of the interface part, that is, the thermal expansion, and to absorb the manufacturing error of the solar cell paddle 3.
[0017]
As indicated by arrows in FIG. 5, the direction of the line connecting the key groove 31 of the bush 21 and the center (line connecting the key 32 of the bush 22 and the center) arranged in the interface portion is the radial direction with respect to the drive mechanism 5. Is directed to. Accordingly, the two holding / releasing mechanisms 7 located in the front and rear centers are directed in the vertical direction, the two holding / releasing mechanisms 7 located in the middle in the vertical direction are directed in the front and back directions, and are diagonally oriented. The four holding / releasing mechanisms 7 are oriented diagonally. Accordingly, the mechanical restraining force in the interface portion can be increased and the thermal stress can be released by the bush pairs 21 and 22 having substantially the same weight as the conventional one.
[0018]
On the other hand, as shown in FIGS. 6 and 7, an annular convex portion 33 is formed on the upper surface of the lower bush 23 of the bush pair 23, 24 in the solar cell paddle 3. An annular recess 34 into which the annular projection 33 of the bush 23 is fitted is formed on the lower surface of the upper bush 24. The side surfaces of the annular convex portion 33 and the annular concave portion 34 are tapered surfaces, and the annular convex portion 33 and the annular concave portion 34 are easily fitted. The bushes 23 and 24 are made of carbon fiber reinforced plastic or a material equivalent thereto, and are not affected by the difference in linear expansion coefficient.
[0019]
In the holding and releasing mechanism of the solar cell paddle 3 having such a configuration, when the solar cell paddle 3 is held in the folded holding position, the rod guided to the console 8 through the bushes 21 to 24 is connected to the rod tension in the console 8. Hold tension by means. Thereby, the yoke 11 and the panels 13 to 15 are folded, and all the first bush pairs 21 and 22 are fitted, and all the second bush pairs 23 and 24 are fitted. At this time, the first bush pair 21, 22 keeps the distance between the support structure 2 and the yoke 11 and mechanically restrains the support structure 2 and the yoke 11. In addition, the second bushing pair 23, 24 has a space between the yoke 11 and the first panel 13, a space between the first panel 13 and the second panel 14, and a space between the second panel 14 and the third panel 15. While maintaining an interval, the yoke 11 and the panels 13 to 15 are mechanically restrained. And when environmental temperature changes, the keyway 31 and the key 32 of the 1st bush pair 21 and 22 relieve | moderate the thermal stress based on the difference of a linear expansion coefficient. In addition, since the difference of the linear expansion coefficient of the 2nd bush pair 23 and 24 can be disregarded, thermal stress does not generate | occur | produce in them.
[0020]
As described above, since the bushes 21 and 22 positioned on the diagonal line of the side surface 4 of the pointing structure 2 have conventionally used bushes that contact with a flat surface, the movement of the support structure 2 and the yoke 11 in the surface direction is mechanically performed. However, in the present invention, the bushing pair 21 and 22 each having the key groove 31 and the key 32 that engage with each other is used, so that the force that mechanically restrains the movement in the surface direction is applied. It can be increased. Further, since the bushes 23 and 24 in the solar cell paddle 3 are conventionally bushes that come into contact with each other on a flat surface, the yoke 11 and the panels 13 to 15 could not be mechanically restrained. Then, since the bush pairs 23 and 24 each having the annular convex portion 33 and the annular concave portion 34 that are fitted to each other are used, it is possible to mechanically restrain their movement in the surface direction.
[0021]
In the first embodiment described above, the direction of the line connecting the key groove 31 and the center of the bush 21 (the line connecting the key 32 and the center of the bush 22) is directed radially to the drive mechanism 5; It is not necessary to match the mechanism 5 strictly, and it can be directed in an appropriate direction as long as thermal stress is reduced. Further, the keyway 31 and the key 32 are provided in the bush 21 and the bush 22, respectively, and the annular convex portion 33 and the annular concave portion 34 are provided in the bush 23 and the bush 24, respectively. Further, the shapes of the keyway 31 and the key 32 are not limited, and other shapes can be used. Then, instead of relieving the thermal stress by the keyway 31 and the key 32, the thermal stress can be relieved by using a directional elastic body or a link mechanism.
[0022]
【The invention's effect】
As described above, according to the present invention, when the unfolded structure is folded, the first bush pair is engaged by the key and the key groove, and the second bush pair is formed by the annular convex portion and the annular concave portion. And the line connecting the key or keyway of the first bushing pair and the center of the bushing is directed in the radial direction with respect to the drive mechanism, so that the holding load is not increased and the deployment structure is not increased. The mechanical restraining force can be increased, and there is an effect that a deployment structure heavier than the conventional one can be held.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a spacecraft including a solar cell paddle according to a first embodiment of the present invention.
FIG. 2 is a perspective view showing a state in which the solar cell paddle of FIG. 1 is folded.
3 is a partially enlarged front view showing the satellite structure and solar cell paddle in the state shown in FIG. 2;
FIG. 4 is a perspective view showing a pair of bushes arranged in an interface unit separately.
5 is a perspective view showing the solar cell paddle on the right side of FIG. 2 separately from the satellite structure. FIG.
FIG. 6 is a perspective view showing a pair of bushes disposed in a solar cell paddle separately.
FIG. 7 is a cross-sectional view showing a pair of bushes arranged in a solar cell paddle separately.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Spacecraft, 2 Support structure, 3 Solar cell paddle (deployment structure), 5 Drive mechanism, 7 Holding | release release mechanism, 11 Yoke, 13-15 Panel, 21,22 1st bush pair, 23,24 2nd Bush pair, 31 keyway, 32 key, 33 annular convex part, 34 annular concave part.

Claims (4)

  A plurality of panels connected in a foldable manner and supported by a drive mechanism of a support structure, and a plurality of panels fixed to the support structure and an adjacent panel, and engaged with each other when the deployment structure is folded. A deployment structure holding and releasing mechanism comprising: a first bush pair; and a plurality of second bush pairs fixed to a panel and engaged with each other when the deployment structure is folded. When folded, the plurality of first bush pairs are engaged by a key and a key groove, the plurality of second bush pairs are engaged by an annular protrusion and an annular recess, and the first A mechanism for holding and releasing a deployment structure of a spacecraft, wherein a line connecting a key or keyway of one bush pair and a center of the bush is directed in a radial direction with respect to the drive mechanism.   2. The space navigation deployment structure holding and releasing mechanism according to claim 1, wherein the first bushing pair is an elastic body having directionality.   The mechanism for holding and releasing the spacecraft deployment structure according to claim 1, wherein the first bush pair is engaged by a link mechanism. Holding release mechanism of claim 1 deployable structure of the space vehicle according to the second bushing pair is characterized by comprising a fiber-reinforced plastic.

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