JPH028959B2 - - Google Patents

Description

Claim 1: A deployable truss having at least one foldable module 10, comprising: a. two fixed frames formed in a rectangular shape, each comprising an upper member 24, a lower member 26, and side members 28, 30; 12, 14, b. Two gate assemblies extending between the fixed frames and each pivotally connected to both of the fixed frames, the gate assemblies being hinged so as to be foldable near the center of each; 16, 18, and c. The gate assembly 16, 18, and c includes two base members 20, 22 extending between and pivotally connected to the fixed frames and collapsible near the center; The side members 28, 30 and the base members 20, 22 are rectangular in shape;
When the module 10 is folded, the fixed frame 12,
14 face each other and approach each other, the gate assemblies 16, 18 are bent between the fixed frames 12, 14 toward the center of the upper member 24, and the base members 20, 22 are bent toward the center of the upper member 24. The fixed frame 12, 1 bends upward near the
4. A truss in which the gate assemblies 16, 18 and the base members 20, 22 are compactly folded into a flat rectangle.

2. In the truss according to claim 1, the fixed frame and the fixed frame are arranged closely adjacent to each other with the gate assembly folded in between when the module is in the folded configuration. A truss in which a gate assembly is disposed and in which, when the module is in a deployed configuration, the fixed frames are spaced apart by a distance approximately equal to the width of the gate assembly before folding.

3. The truss of claim 2, wherein each gate assembly is pivotally attached to both side members of the fixed frame.

4. The truss according to claim 3, wherein each of the base members is pivoted to the outside of both fixed frames at an intersection where the lower member and the side member of the fixed frame intersect.

5. The truss according to claim 4, wherein the base member is foldable in a plane parallel to the plane of the side member to which the base member is connected.

6. In the truss according to claim 5, the height of the gate assembly is made smaller than the distance between the upper member and the lower member of the fixed frame. a truss pivotally disposed between the upper member and the lower member when in the modular folded configuration;

7. The truss of claim 6, wherein: (a) each fixed frame has two side diagonal braces, and (b) the upper members of both fixed frames have two side diagonal braces extending between the upper members. (c) two lower diagonal braces, the lower members of both of the fixed frames extending between the lower members.

8. The truss of claim 7, wherein the module includes an actuation device for folding and unfolding the module.

9. The truss of claim 8, wherein the actuation device includes at least one motor drivingly connected to a deployment linkage, the deployment linkage being connected to one of the base members. Possibly a truss capable of folding or unfolding the base portion upon actuation of the motor.

10. The truss of claim 9, wherein the truss has at least one panel attached to the module such that it can be folded together with the module.

11. The truss according to claim 10, including two panels, each of which can be folded together with the base member between the fixed frames when the module is in a folded configuration. and a truss attached to a portion of each foundation member.

12. The truss according to claim 11, wherein the panels are hinged to each other along a hinge line in the center of the base member.
A truss wherein the faces of the panels substantially abut each other when the module is in the folded configuration.

13. The truss according to claim 12, wherein the gate assembly is configured such that the gate assembly and the panel can be folded together without interfering with each other.

14. The truss of claim 13, wherein the gate assembly includes two gates of substantially the same size, each gate including a horizontal arm and an angular arm disposed between the gates. hingedly connected to a transfer link, said transfer link having a width at least equal to the thickness of said two panels such that said panel folds below said transfer link when said module is in the folded configuration; truss.

15. The truss according to claim 7, wherein the upper diagonal brace is extendable and retractable so that the length of the module is variable when the module is in the folded or unfolded configuration.

16. The truss of claim 9, wherein the lower diagonal brace extends crosswise over the top surface of the panel and is foldable with the panel.

17. The truss of claim 9, wherein a motor attached to the base member folds and unfolds the base member substantially simultaneously.

18. The truss of claim 9, wherein the deployment linkage has a latch crank and a latch arm pivotally connected at their ends, and the motor is fixed to a first half of one of the foundation members. the other end of the latch arm is pivotally connected to the second half of the one of the base members, and the other end of the latch crank is drivingly connected to the motor; The torque for folding or unfolding the first half and the second half of the base member is transmitted from the motor through the latch crank and the latch arm to the first half and the second half. Truss added to the section.

19. The truss according to claim 10, wherein a plurality of outrigger rods are used to support the panel, the outrigger rod being fixedly attached to one of the side members and supporting the panel. A truss that is pivotally attached to one side edge of a truss.

20. A truss having a plurality of modules according to claim 1, and formed so that adjacent modules use a common fixed frame.

21. A truss having a plurality of modules according to claim 1, and formed so that adjacent modules use a common gate assembly.

22. A truss having a plurality of modules according to claim 1, and formed so that adjacent modules use a common fixed frame and a common gate assembly.

FIELD OF THE INVENTION This invention relates to trusses, and more particularly to new and improved deployable and compact collapsible trusses for supporting components such as solar panels.

Description of the Prior Art It is necessary for trusses used in certain applications to be scalable. Large space structures, such as those supporting arrays of solar panels during space orbit, must be able to be accommodated during launch within the limited space available within the launch vehicle. Moreover, once in space, such structures must be able to scale to relatively large dimensions to support large arrays of solar cells.

Various types of deployable trusses have been developed that can be expanded from a collapsed configuration to an expanded or deployed configuration and that can be repositioned to collapse the truss members. In some cases, emphasis has been placed on the structural integrity of the truss over compactness, resulting in larger and heavier truss members. The overall size of such a truss when deployed is therefore relatively small due to launch vessel capacity and weight limitations. As a result, the size of the array of solar cells supported by the truss is also relatively small, making it difficult to justify the high cost of launching the truss into space.

On the other hand, efforts have been made to minimize the folded dimensions of deployable trusses in order to meet launch vessel size limitations while maintaining large deployed dimensions of the truss; defect occurred. Three types of structural defects are problematic. namely bending stiffness, torsional stiffness, and thermal stability. Ideally, each of these properties should be maximized upon truss deployment to provide a stable, long-life platform for solar panels and other components supported by the truss. One way to maximize bending and torsional stiffness is to increase the size of the truss relative to the solar panel it is supporting. For example, by increasing the height of the truss in a direction perpendicular to the surface of the solar panel it supports, the bending and torsional stiffness of the truss-panel structure can be increased considerably. A tall truss also improves the thermal stability of the truss, ie, its resistance to bending caused by temperature differences between the various members of the truss. The greater the distance between two truss members that are compatible with different temperatures,
The bending caused by temperature differences is small. However, attempts to improve current deployable truss structures by increasing the height of the truss have the disadvantage of resulting in a folding truss that is larger than originally designed and is therefore likely to be too large to be accommodated within the launch vehicle.

In view of the above-mentioned problems, it is one of the objects of the present invention to provide a deployable truss that is relatively large when deployed but can be folded into a compact size.

Another object of the invention is to provide a deployable truss with increased bending and torsional stiffness to better support panel rows.

Yet another object of the invention is to provide a deployable truss with increased thermal stability.

That is, according to the present invention, there is provided a deployable truss having at least one foldable module, comprising: a) two fixing frames formed in a rectangular shape, each comprising an upper member, a lower member and a side member; b) a fixing frame. two gate assemblies extending between the two frames and each pivotally connected to both the fixed frames, and hinged so as to be foldable near the center of each; and c. between the two fixed frames; The gate assembly, the side members, and the base member are rectangular in shape and include two base members extending and pivotally connected to both fixed frames and collapsible near the center; the gate assembly, side members, and base member are rectangular in shape; The frames approach each other in opposition, the gate assembly bends between the fixing frames toward the center of the upper member, and the base member bends upwards near their center until the gate assembly is fixed. A truss is provided in which the frame, gate assembly, and base member are compactly folded into a flat rectangle.

DISCLOSURE OF THE INVENTION The invention, according to one embodiment thereof, includes a deployable truss that includes at least one foldable module. Each module includes two fixed frames, two gate assemblies, and two base members arranged to be foldable into a compact size. The gate assembly extends between the fixed frames, is pivotally connected to the frames, and is hinged for bending about the center. The base member extends between both fixed frames, is pivotally connected to these frames, and is hinged so as to be bendable near the center.

In a specific embodiment of the invention, two panels are attached to the base member and are foldable together with the module. A motor and a deployment linkage may be coupled to the base member to allow the module to be folded and deployed. The truss can have multiple modules, in which case adjacent modules are arranged to share a fixed frame or gate assembly.

[Brief explanation of drawings]

The invention will be better understood from the following description in conjunction with the accompanying drawings.

FIG. 1 is a perspective view of the module of the present invention in an expanded configuration.

FIG. 2 is a side cross-sectional view of the module taken along line 2--2 of FIG.

FIG. 3 is an enlarged view with some parts removed of the motor and the deployable linkage.

FIG. 4 is a side view of the motor and deployment linkage in an intermediate position.

FIG. 5 is a side view of the motor and deployment linkage in the folded position.

FIG. 6 is a perspective view of the module in a partially folded configuration.

FIG. 7 is a perspective view of the module in its folded configuration.

FIG. 8 is a perspective view of the multi-module truss in its unfolded configuration.

FIG. 9 is a perspective view of another multi-module in an expanded configuration.

FIG. 10 is a perspective view of the multi-module truss of FIG. 8 in a folded configuration.

FIG. 11 is a perspective view of the multi-module truss of FIG. 9 in a folded configuration.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, and with particular reference to FIG. 1, there is shown a collapsible module 10 of a deployable truss of the present invention. The truss can include one or more modules, but for clarity only one module 10 will be described initially.

FIG. 1 shows the module 10 when deployed or expanded. The module 10 includes two fixed frames 12, 14 and two gate assemblies 16, 18.
and two foundation members 20 and 22.

Each of the two fixed frames 12, 14 is preferably approximately rectangular and has an upper member 24, a lower member 2
6 and two side members 28,30. Fixed frames 12, 14 may each also include two lateral diagonal braces 32, 34 extending between opposite corners of the fixed frame to increase structural strength.

Gate assemblies 16 and 18 extend between and are pivotally connected to fixed frames 12 and 14, respectively. In the deployed configuration of FIG. 1, the fixed frames 12, 14 are spaced apart by a distance approximately equal to the width of the expanded gate assembly. To enable folding of module 10, gate assemblies 16, 18 are each hinged so that they can bend near the center. The gate assemblies are configured so that they and other components of module 10 can be folded together without interference. As best seen in FIG. 2, one suitable configuration for the gate assembly includes two gates 36, 38 of approximately the same size.
Gates 36, 38 each include a horizontal arm 40 and an angled arm 42. Disposed between and hingedly connected to the gates 36, 38 is a transition link 44 which includes a hinge pin for receiving the inner ends of the horizontal arm 40 and the angular arm 42. The transition link 44 preferably also includes an over-center latch for securing the gate assemblies 16, 18 during deployment. Gates 36, 38
The outer ends of the horizontal arm 40 and the angular arm 42 of both side members 28, 30 of the fixed frames 12, 14
It is pivoted to. This arrangement allows the gate assemblies 16, 18 to move as the fixed frames 12, 14 move towards each other during folding of the module 10.
It can be folded towards the inside of the module 10 at the transition links 44. Of course, gate assemblies having other suitable shapes may be used if desired.

Returning to FIG. 1, the height of the gate assemblies 16, 18 is preferably less than the distance between the upper and lower members 24, 26 of the fixed frames 12, 14. Such a height difference allows the gate assembly to be pivotally disposed between the upper and lower members when module 10 is in the collapsed configuration.
This will be explained more fully below.

As seen in FIG. 1, the base members 20, 22 each extend between the fixed frames 12, 14 and outside of these frames, preferably near the intersection of the lower member 26 and the side members 28, 30. It is pivoted. The base members 20, 22 are hinged so as to fold near the center, so that each base member is folded in a plane parallel to the plane of the side member 30 to which it is connected. Half portion 4 of each of the foundation members 20, 22
6, 48 can be hinged together, or the half members can be attached to other components that are hinged together, as shown in FIG.

Fixed frames 12, 14, gate assemblies 16, 18,
Base members 20, 22 may be molded from any suitable material, such as, for example, graphite epoxy compound. These members can have any desired cross-sectional shape.

For structural rigidity, module 10 preferably includes upper members 24 of both fixed frames 12, 14.
two upper diagonal braces 5 extending diagonally between them;
0,52 and two lower diagonal braces 54,56 extending diagonally between the lower members 26 of both the fixed frames 12,14.

The module 10 described above is a unitary structure that can be used alone. Module 10 can also have additional components attached thereto. For example, module 10 may include an antenna membrane consisting of a stretched mesh (not shown) spanning it or spanning several modules. Alternatively, as shown in FIG. 1, module 10 can include one or more panels, such as a solar panel.

When using panels, each module 10 preferably consists of two panels 5 attached to the module so that they can be folded together with the module.
Including 8,60. The panel 58 is the foundation member 20,2
2 and the other panel 60 is attached to each other half 48 of the base members 20,22. The panels 58, 60 are attached to the base members 20, 20 by bolts 62 or the like in any suitable manner.
Can be installed on.

Panels 58, 60 are integrally hinged to hinge 64 along the hinge line by dotted line 66. To enable panels 58, 60 to be folded upwardly, hinges 64 are preferably located on the underside of the panels, thus as shown in dotted lines. The hinge line 66 extends adjacent the center of the base members 20, 22 where the base member halves 46, 48 abut. As previously shown, the hinge 64 also connects the base member 20,
Provides hinged support for halves 46, 48 of 22. The outer edges 68 of the panels 58, 60, parallel to the hinge line 66, extend adjacent to the lower member 26 of the fixed frames 12, 14, while the end edges 70 of the panels extend as far as desired from the base member 20, It may extend beyond 22.

To fold and unfold the module 10,
Any suitable internal or external actuation device may be used. One suitable actuation device includes two motors 72, 74 that are electrically, hydrodynamically, or otherwise driven. .
As shown in FIG. 1, one of the motors is located adjacent to each base member 20, 22, and a deployment linkage 7 connects the two halves 46, 48 of each base member.
6 and 78 in a driving manner. Motor 72, 7
4 actuates the deployment linkages 76, 78, which in turn impart a folding or unfolding motion to the base members 20, 22. Motors 72, 74 are preferably synchronized so that the base members fold or unfold simultaneously.

An example of a suitable motor and deployment linkage is the third
As shown in the figure. Motor 72 is preferably mounted on one half 48 of base member 20 and is drivingly connected to latch crank 80. A crank 80 is pivotally connected to one end of a latch crank 84 via a hinge pin 82. The other end of the latch arm 84 is connected to the other half 4 of the base member 20 via a hinge pin 86.
It is pivoted to 6. Rotation of latch crank 80 counterclockwise by motor 72 causes latch arm 84 to rotate counterclockwise. As can be seen in FIG. 4, the torque applied by the motor 72 through the latch crank 80 and latch arm 84 causes the halves 46, 48 of the base member 20 as well as the panels 58, 60 to move around the hinge 64 and the panel Fold until the bottom surfaces of 58 and 60 substantially abut. The combined length of latch crank 80 and latch arm 84 is at least equal to the thickness of the two panels 58, 60 so that the two panels 58, 60 can be folded downwardly as shown in FIG. Reversal of the direction of the motor causes the two halves 46, 48 of the base member 20 to unfold or unfold about the hinge 64.

The module 10 has a developed shape shown in FIG.
Folding is performed as follows into the folded shape shown in FIG.

Actuating devices, such as motors 72, 74 shown in FIG. 1, initiate folding of base members 20, 22 in the manner described above. As can be seen in FIG. 6, when base members 20, 22 are folded, they also cause panels 58, 60 to fold. at the same time,
The base member during folding draws the fixed frames 12, 14 closer together. Correspondingly, the gate assemblies 16, 18 are folded toward the interior of the module 10 near the center. Preferably,
The upper diagonal braces 50, 52 are attached to the fixed frames 12, 14.
The braces are extendable so that they become shorter as they approach each other, and likewise become longer as the fixed frames are pulled apart during deployment. An example of a stretchable configuration is a stretchable taped tube structure that includes an inner tape and an outer tube. The inner tape slides inside the outer tube until it reaches its intended maximum length.
The length of the entire diagonal member is made variable. Lower diagonal braces 54, 56 extend across the top surfaces of panels 58, 60, and these braces preferably
It can be folded together with the panels and substantially stranding their original length. The gate assemblies 16 and 18 are shaped like the gate assembly and panel 5.
8 and 60 can be folded simultaneously without interfering with each other. Specifically, the inverted V-shape formed by the two angled arms 42 of each gate assembly allows the folding panels 58,6
When 0 becomes a folded shape or a unfolded shape, a gap is given.

Turning now to FIG. 7, the folded configuration of module 10 is shown. The base members 20, 22 are provided on the outside of the side members 28, 30 of the fixed frames 12, 14,
and adjacent to these are folded. Fixed frame 1
2, 14 are placed closely adjacent to each other, with the gate assemblies 16, 18 folded between the fixed frames.
As previously mentioned, the height of the gate assemblies 16, 18 is less than the distance between the upper and lower members 24, 26 of the fixed frame so that the gate assemblies in the collapsed position have at least a portion of them and the lower member. Thus, the space that would have been a gap between the fixed frames if the above did not occur is replaced by the lower diagonal brace 54,
56 and the folded gate assemblies 16, 18, thereby reducing the size of the folded module 10 accordingly.

Panels 58, 60 are folded between fixed frames 12, 14 such that the panel surfaces substantially abut each other. The width of each transfer link 44 of the gate assembly is
The thickness is equal to that of at least two panels 58, 60 so that when the module 10 is in the folded configuration, the panels are folded under the transition links. Similarly, the deployment linkage 76 is spaced at least equal to the thickness of the two panels 58, 60 so that the panels are stored below the deployment linkage in the folded configuration. The module 10 unfolds from the folded configuration shown in FIG. 7 to the unfolded configuration shown in FIG. 1 in a manner opposite to that described above.

The gate assemblies 16, 18 are partially attached to the fixed frame 1.
2, 14, but the base member 20,
22 is folded along the fixed frame, the height of the module measured along the side member 28 from the panel edge 68 to the hinge line 66.
The ratio of panel 58 measured to width is greater than that in many prior art trusses.
The greater this ratio of modules to panels, the more
The bending and torsional stiffness of the module 10 is increased, thus providing greater stability and longer life support to the panel. Long side members 28, 30
also increases the thermal stability of module 10. When the temperature of the upper member 24 is different than the temperature of the lower member 26, the greater the distance between the upper and lower members, the less the module will bend due to the thermal difference.

Similarly, by utilizing the present folding method of the module 10, the fixed frames 12, 14, the gate assemblies 16, 1
8 and the base members 20, 22 can be made of members with larger cross-sectional areas than in many prior art trusses, without significantly increasing the size of the folded module. Such a large cross-sectional area also increases the bending and torsional stiffness of module 10.

The truss structure of the present invention can include one or more modules 10. As shown in Figure 8,
A plurality of foldable modules 10 are placed adjacent to each other so that they use a common fixed frame. Also shown in FIG. 9, truss structures including multiple modules 10 not only use common fixation frames 12, 14, but also common gate assemblies.

The multi-module truss described above folds or unfolds in the same manner as described for the single module 10. 10 shows the truss of FIG. 8 in the folded configuration, and FIG. 11 shows the truss of FIG. 9 in the folded configuration. When folded, common fixed frames 12, 14 and adjacent module 1
0 folded panels 58, 60 are placed closely adjacent to each other. This causes the gate assemblies 16, 18 of each module to be folded adjacent to the fixed frame. As a result, the present truss structure is relatively small when in the folded configuration, but quite large when in the unfolded configuration.

Figures 8 and 10 show panels 5 extending a relatively long distance beyond the base members 20, 22.
Also shown is an outrigger bar 88 that can be used to support 8,60. The outrigger bars are each fixedly attached to the side members 28,30 and hingedly attached to the side edges of one of the panels 58,60. As a result, the panel can be folded while the outrigger bar 88 remains in place.

It is to be understood that the invention is not limited to the specific embodiments disclosed, but is intended to include all modifications that may come within the scope of the claims and spirit of the invention.