JP3540161B2

JP3540161B2 - Variable shape truss frame

Info

Publication number: JP3540161B2
Application number: JP17287298A
Authority: JP
Inventors: 佑太郎表; 文宏井上; 康平栗田; 則之古屋
Original assignee: Obayashi Corp
Current assignee: Obayashi Corp
Priority date: 1998-06-19
Filing date: 1998-06-19
Publication date: 2004-07-07
Anticipated expiration: 2018-06-19
Also published as: JP2000008479A

Description

【０００１】
【発明の属する技術分野】
本発明は、基本要素となる最小単位のトラスの一部に伸縮調節可能なトラス部材を組み込んで、形状可変に構成されるトラス架構の改良に関する。
【０００２】
【従来の技術】
従来における形状可変トラス架構の構造例として、特開平４−１４６３５２号公報と実開昭６３−２００９１０号公報のものが知られている。前者の特開平４−１４６３５２号公報のものは、建物の床や屋根を支持するトラス架構に関するもので、上下の弦材と斜材とからなり、１本の上弦材と２本の斜材、及び１本の下弦材と２本の斜材とでそれぞれ構成される三角形のトラスを基本要素の最小単位にして、これらをそれぞれ１本の斜材を共有させながら交互に連結して骨組みしたトラス架構構造において、下弦材に伸縮調整可能な可変長トラス部材を用い、この下弦材を伸縮させることで架構の全体形状を変更可能となしている。即ち、このトラス架構構造によれば、下弦材の長さを上弦材と等しくすると全体として直線的に延びたトラス架構が形成され、上弦材より下弦材の長さを長くするとトラス架構は上弦材側を内側にして湾曲するように上方に向けて屈曲し、上弦材より下弦材の長さを短くすると下弦材側を内側にして湾曲するように下方に向けて屈曲する。
【０００３】
また、後者の実開昭６３−２００９１０号公報のものは、弦材、束材、斜材とで構成された主に宇宙で使用する可変形状のトラスアンテナに関するもので、図６（ｂ）に示すように、共に固定長である一対の弦材１と束材４とを回動自在にピン結合して四辺形の格子状に形成するとともに、各格子の一方の対角線方向に沿って２つの節点２，２を連結する斜材５として可変長トラス部材５ａを配し、これを基本要素の最小単位トラス１０ａにして当該最小単位トラス１０ａを同図（ａ）に示すように、各束材４を共有させつつ多数連設させて骨組みした構造の形状可変トラス架構１０が示されている。即ち、この形状可変トラス架構１０では、各最小単位トラス１０ａの弦材１と束材４とのなす角が直角になるように斜材５の長さを設定すれば、全体として直線状に伸びた形態となる。また、弦材１と束材４とのなす角を直角とせずに、各最小単位トラス１０ａが図６（ｃ）のような平行四辺形となるように斜材の長さを調節して各弦材１と束材４とのなす角度を同一に設定すれば全体として直線状に傾斜した形態となる。また、各最小単位トラス１０ａの弦材１と束材４とのなす角度をそれぞれ任意に変えれば、多角的に屈曲したトラス架構を形成することができる。
【０００４】
【発明が解決しようとする課題】
しかしながら、前者の特開平４−１４６３５２号公報に開示された形状可変トラス架構構造では、上弦材と２本の斜材とにより三角形に構成される上限側の最小単位トラスはその形状が固定されており、トラス架構全体としての形状を変えるにあたっては、可変長の下弦材の長さを伸縮させてこの下弦材を含んで三角形に構成される下弦側の最小単位トラスの形状を変えることにより行っているため、多様な形状への対応度が低かった。また、開閉式の屋根への適用やトラスの運搬などを考慮した場合、小さく折り畳む必要があるが、上弦側の最小単位トラスは、形を変えることができないため、トラス架構全体を小さく折り畳むことができず、限られたスペースに収納するのが困難であった。
【０００５】
一方、後者の実開昭６３−２００９１０号公報に開示された図６のトラス構造のように平行四辺形のトラス格子を連ねたトラス架構構造では、弦材同士並びに束材同士は全て常に平行に保たれるから、トラス架構の全体としての形態を特に図７に示すような円弧形状に設定しようとすると、その円弧に沿わせて、トラス架構基端部の固定側の最小単位トラス７ａから先端側の最小単位トラス７ａにかけて徐々にその各最小単位トラス７ａの変形度合いを強めてゆかねばならず、基端側に対して先端側を９０度まで屈曲させるとその先端部の最小単位トラス７ａを形成する平行四辺形は弦材１、束材４、斜材５がほぼ１直線状に重なって伸びてしまい、トラス本来の荷重を分散して支える機能を失って、強度が極端に低下するという不具合が生じる。また、先端部の最小単位トラス７ａは基端部に対して９０゜以上曲げる様なことはできず、よってトラス架構は四半円弧までしか形成できないという制約がある。
【０００６】
本発明は、上記課題に鑑みてなされたものであり、その目的は、トラスのもつ構造強度を損なうことなく多様な形状に対応し得るとともに、小さく折り畳むことが可能な形状可変トラス架構を提供することにある。
【０００７】
【課題を解決するための手段】
上記の目的を達成するために本発明の請求項１では、一対の弦材と一対の束材とを回動自在に結合して四辺形の格子状に形成するとともに、一方の対角線に沿って両節点間に伸縮調節可能な可変長の斜材を回動自在に結合させて、基本要素となる最小単位トラスを構成し、該最小単位トラスを、束材を共有させつつ多数梯子状に連設して骨組みし、該斜材の長さをそれぞれ任意に調節することで形状変更可能となした形状可変トラス架構において、前記最小単位トラスを構成する一対の弦材相互並びに一対の束材相互の離間距離を十分に保たせながら形状変更すべく、前記一対の弦材のうち少なくとも一方を任意の長さに伸縮調節可能に構成した。
【０００８】
上記構成によれば、基本要素となる四辺形の最小単位トラスを構成する一対の弦材のうちの一方が伸縮調整可能であるから、対をなす２本の弦材の長さを相互に違えて設定し、これに合わせて斜材の長さを調節することで個々の最小単位トラスを２本の弦材同士並びに束材同士が十分に離間した任意の四辺形状若しくは台形状となし得る。このため、トラス架構全体に荷重を分散して十分な強度を確保でき、また弦材と束材とのなす角度を連続的に変えることができ、よって強度を保持したまま多様な形状変更に対応可能となって、その形状変更の自由度が可及的に高まる。
【０００９】
また、２本の弦材の長さを等しくして個々の最小単位トラスの格子形状を平行四辺形にし、斜材を最大限に伸ばせば、弦材、斜材、束材をほぼ一直線に揃えて、可及的に小さく折り畳むことができる。
【００１０】
また、本発明の請求項２では、前記最小単位トラスを構成する一対の弦材に、伸縮調整可能な可変長トラス部材と固定長トラス部材とを用い、該最小単位トラスを多数梯子状に骨組みした状態で該可変長トラス部材と固定長トラス部材とを交互に配置する構成とした。
【００１１】
当該構成とすれば、トラス架構を湾曲形成するにあたって、湾曲内側の可変長トラス部材を伸ばす一方、湾曲外側の可変長トラス部材を縮めることで、片側に可変長トラス部材を連ねて配する場合に比して、曲率を大きく形成することができ、または曲率を同じに形成するならば、各可変長トラスの伸縮量を少なくすることができる。
【００１２】
【発明の実施の形態】
以下、本発明にかかる形状可変トラス架構について、添付図面に示す実施形態を例にして詳細に説明する。
【００１３】
図２は本発明の形状可変トラス架構を片持ち梁に適用した場合の概略構成図であり、同図（ａ）はその架構全体形態の基準となる基本形を示す側面図であり、同図（ｂ）は、このトラス架構の１つの格子部分をなす基本要素としての最小単位トラスを示す側面図である。図２（ａ），（ｂ）に示すように、本発明の形状可変トラス架構１０は、基本要素となる最小単位トラス１０ａが多数連設されることによって形成されるが、この最小単位トラス１０ａは、一対の弦材１ａ，１ｂと一対の束材４，４とがピン継手３を介して相互に回動自在に結合されて四辺形状の格子に形成されるとともに、さらにその格子の一方の対角線に沿って弦材１ａ，１ｂと束材４，４との接合点の両節点間に、上記ピン継手３を介して可変長トラス部材５ａでなる伸縮調整可能な１本の斜材５が回動自在に結合配置され、かつ上記弦材１ａ，１ｂのうち少なくとも一方には上記斜材５と同様の可変長トラス部材１ｂが用いられた構造となっている。ここで本実施形態においては、２本一対の弦材１ａ，１ｂのうち一方に可変長トラス部材１ｂが用いられ、他方に固定長トラス部材１ａが用いられた構成となっている。
【００１４】
そして、形状可変トラス架構１０は、上記最小単位トラス１０ａが多数その束材４を共有されながら一方向に向けて梯子状に連設結合されて骨組みされることにより形成され、図２（ａ）に示すように一直線状に延びる形態をその基本形状としている。ここで、本実施形態にあっては、弦材１ａ，１ｂにおける伸縮可能な可変長トラス部材１ｂと伸縮不可な固定長トラス部材１ａとを交互に配置して多数の最小単位トラス１０ａを連結している。また、斜材５も２つの対角線方向に沿わせて隣り合う最小単位トラス１０ａごとに交互に違えて配している。
【００１５】
以上の構成でなる形状可変トラス架構１０にあっては、各最小単位トラス１０ａにおける一対の弦材１ａ，１ｂのうち可変長トラス部材１ｂの長さを固定長トラス部材１ａの長さと同一に設定すると、従来のトラス架構とほぼ同様となる。つまり、斜材５の可変長トラス部材５ａの長さを調節して弦材１ａ，１ｂと束材４とを直角に設定すると、各最小単位トラス１０ａの格子は長方形あるいは正方形の矩形を呈して、トラス架構１０の全体としての形態は直線状にほぼ水平に延びた基本形状となる。また、斜材５の長さを調節して各最小単位トラス１０ａの格子を同一角度の平行四辺形に設定すると、全体としての形状は直線状に傾斜した形状となる。さらに、各最小単位トラス１０ａの格子をそれぞれ任意角度の平行四辺形に設定すれば全体としての形態は多角的に屈曲した形状になる。
【００１６】
ところで、本発明のトラス架構１０では、最小単位トラス１０ａを構成している２本の弦材１１ａ，１ｂのうち少なくとも１方と斜材５とに伸縮可能な可変長トラス部材１ｂ，５ａを用いたため、２本の弦材１ａ，１ｂの相互の長さを違えることにより、最小単位トラス１０ａは図２（ｃ）のような四辺形に形成することが可能で、かつ斜材５の長さも合わせて調節することにより台形若しくはこれに極近い形状に形成することができる。
【００１７】
即ち、可変長トラス部材１ｂでなる弦材１の長さを伸縮調節してその長さを固定長トラス１ａでなる弦材１よりも長くあるいは短くすることでこれら２本の弦材１ａ，１ｂを十分に離間させたままで、弦材１ａ，１ｂと束材４とのなす角度を連続的に任意に変えることができる。このように、各最小単位トラス１０ａが形成する格子の形状を、その一対の弦材１ａ，１ｂ相互並びに一対の束材４，４相互の離間距離を十分に保たせながら、４つの角度がそれぞれ異なる任意の四辺形状、若しくは台形状とすることにより、トラス架構１０全体に荷重を分散して十分な強度を確保することが可能になり、よって強度を保持したまま、例えば図１（ａ）〜（ｆ）に示すようにトラス架構１０を自由度高く形状変更することができるようになる。
【００１８】
特に、本実施形態の形状可変トラス架構１０では、最小単位トラス１０ａの格子形状を台形若しくはこれに極近似した形状に設定できるから、全体として円弧状に湾曲する形態に形成する場合にあっても、図３と図４とに示すように、弦材１ａ，１ｂ同士と束材４，４同士とを十分に離間させたまま湾曲させてゆくことができ、先端側の最小単位トラス１０ａの格子形状は従来のように一直線状に潰れることがなく、湾曲中心角が９０度を超えても十分な強度を確保でき、半円弧あるいは環状にも形成可能である。
【００１９】
また、湾曲方向内側に配した可変長トラス部材１ｂでなる弦材１を縮める一方、湾曲方向外側に配された可変長トラス部材１ｂでなる弦材１を伸ばすことにより、曲率を大きくして湾曲形成することもでき、曲率の大小に対しても高い対応度が得られる。特に、形成しようとする所望の仮想円弧の法線方向に束材４を配置すれば、２本の弦材１ａ，１ｂの間隔は最大となりトラス架構１０の強度確保には極めて効果が高い。
【００２０】
また、開閉式の屋根への適用やトラス架構の運搬等を考慮した場合、小さく折り畳む必要があるが、本実施形態の形状可変トラス架構構造によれば図１（ｆ）に示すように小さく折り畳むことが可能で、収まりも良いため、限られたスペース内に効率良く収納することができ、運搬性にも優れたものになる。も容易で効率が良い。さらに、折り畳んだ状態から最小単位トラス１０ａを広げてトラス架構を展開するにあたって、伸縮可能な各トラス部材５ｂ，１ｂの伸縮率の設定を個々に適宜に変えることによって図１（ｂ）〜（ｅ）に示すように複雑な形状も容易に形成することができる。さらには、図３に示すように基端側を地盤等に固設するなどして、半円弧形や蒲鉾形等の開閉式屋根にも適用できる。
【００２１】
なお、以上の説明では、最小単位トラス１０ａを一方向に連設させたトラス架構１０を基本例として説明したが、当該トラス架構１０を多数横方向（紙面方向）に並設して連結することにより、立体的な構面を持つトラス架構が形成可能である。
【００２２】
また、上記実施形態では、弦材１ａ，１ｂに伸縮可能な可変長トラス部材１ｂと固定長トラス部材１ａとを用いて、これらを交互に連結した例を示したが、これは上弦方向への屈曲性能と下弦方向への屈曲性能とを等価に得るために配慮したものであり、その屈曲性能を等価にする必要がない場合には、弦材１ａ，１ｂの配列はこれに限らず、最小単位トラス１０ａを構成する２本の弦材１ａ，１ｂのうち１本が伸縮可能であれば良く、例えば図５に示すように伸縮可能な弦材１ｂを上弦側に、固定長の弦材１を下弦側にそれぞれ別々に連続させて配設したり、あるいは不規則に配設しても同様の効果を得ることが可能である。
【００２３】
【発明の効果】
以上説明したように、本発明にかかる形状可変トラス架構によれば、基本要素となる四辺形の最小単位トラスを構成する一対の弦材のうちの一方が伸縮調整可能であるから、対をなす２本の弦材の長さを相互に違えて設定し、これに合わせて斜材の長さを調節することで個々の最小単位トラスを２本の弦材同士並びに束材同士が十分に離間した任意の四辺形状若しくは台形状となし得、しかも弦材と束材とのなす角度を連続的に変えることができるため、隣接する最小単位トラスを多様な角度で屈曲させることができ、もって多様な形状に対応してトラス架構の全体形態を形成できるとともに、トラス架構にかかる荷重を分散することができ、トラス架構の構造強度を十分に確保し得る。
【００２４】
また、必要に応じ、小さく収まり良く折り畳むことが可能であり、よって限られたスペース内に効率よく収納することができるとともに、運搬性にも優れたものとなる。さらに、折り畳んだ状態から延伸させてトラス架構を所望の形態に展開するにあたり、伸縮可能な弦材と斜材との各トラス部材の伸縮率を個々に適宜に変えることによって多様な形状に容易に形成でき、開閉式屋根などへの適用にも極めて有効である。
【００２５】
また、前記最小単位トラスを構成する一対の弦材に、伸縮調整可能な可変長トラス部材と固定長トラス部材とを用い、この最小単位トラスを多数梯子状に骨組みした状態で可変長トラス部材と固定長トラス部材とを交互に配置する構成とすれば、トラス架構の形態を湾曲させるにあたって、湾曲内側の可変長トラス部材を伸ばす一方、湾曲外側の可変長トラス部材を縮めることで、片側に可変長トラス部材を連ねて配する場合に比して、曲率を大きく形成することができ、または曲率を同じに形成するならば、各可変長トラスの伸縮量を少なくすることができる。
【図面の簡単な説明】
【図１】本発明の第１実施形態にかかる形状可変トラス架構の各種形状変形例を示す図である。
【図２】本発明の第１実施例にかかる形状可変トラス架構の概略構成図で、同図（ａ）はその架構全体形態の基準となる基本形を示す側面図であり、同図（ｂ）は、このトラス架構の１つの格子部分をなす基本要素としての最小単位トラスを示す側面図、同図（ｃ）は最小単位トラスを変形させた状態の一例を示す側面図である。
【図３】本発明の形状可変トラス架構の第２実施形態を示す図である。
【図４】図３の一部拡大図である。
【図５】本発明の形状可変トラス構造の第３実施形態を示す図である。
【図６】従来の形状可変トラス架構の一例を示す概略構成図である。
【図７】図６の形状可変トラス架構を円弧状に湾曲形成する場合を示す図である。
【図８】図７の一部拡大図である。
【符号の説明】
１弦材
１ａ固定長トラス弦材
１ｂ可変長トラス弦材
２接合材
３自在継ぎ手
４束材
５斜材
５ｂ可変長トラス斜材
７ａ最小単位トラス
１０トラス架構
１０ａ最小単位トラス[0001]
TECHNICAL FIELD OF THE INVENTION
TECHNICAL FIELD The present invention relates to an improvement of a truss frame that is configured to be variable in shape by incorporating a truss member that can be expanded and contracted into a part of a minimum unit truss that is a basic element.
[0002]
[Prior art]
Japanese Patent Application Laid-Open No. 4-146352 and Japanese Utility Model Application Laid-Open No. 63-200910 are known as examples of the structure of a conventional variable shape truss frame. The former Japanese Patent Application Laid-Open No. 4-146352 relates to a truss frame supporting a floor or a roof of a building, and comprises upper and lower chords and diagonal members, one upper chord member and two diagonal members, and Truss truss frame composed of triangular truss composed of one lower chord and two diagonal members, each of which is a minimum unit of a basic element, and which are connected alternately while sharing one diagonal member. In the structure, a variable-length truss member capable of expansion and contraction is used for the lower chord material, and the entire shape of the frame can be changed by expanding and contracting the lower chord material. That is, according to this truss frame structure, when the length of the lower chord material is equal to the upper chord material, a truss frame extending linearly as a whole is formed, and when the length of the lower chord material is made longer than the upper chord material, the truss frame becomes the upper chord material. When the length of the lower chord is shorter than that of the upper chord, the lower chord is bent downward with the inner side of the lower chord inward.
[0003]
The latter one disclosed in Japanese Utility Model Application Laid-Open No. 63-200910 relates to a variable-shaped truss antenna mainly composed of a string, a bundle, and an oblique material and used in space. As shown, a pair of chord members 1 and a bundle member 4 both having a fixed length are rotatably pin-connected to each other to form a quadrangular lattice, and two diagonal lines along one diagonal direction of each lattice. A variable-length truss member 5a is arranged as a diagonal member 5 connecting the nodes 2 and 2, and the minimum unit truss 10a is used as a basic element, and the minimum unit truss 10a is used as shown in FIG. A variable-shaped truss frame 10 having a framed structure in which a plurality of trusses 4 are shared while sharing the same 4 is shown. That is, in the variable-shaped truss frame 10, if the length of the diagonal member 5 is set so that the angle between the chord member 1 and the bundle member 4 of each minimum unit truss 10a is a right angle, the truss member will extend linearly as a whole. It becomes a form. Also, the angle between the string member 1 and the bundle member 4 is not set to be a right angle, and the length of the diagonal member is adjusted by adjusting the length of the diagonal member so that each minimum unit truss 10a becomes a parallelogram as shown in FIG. If the angle between the chord material 1 and the bundle material 4 is set to be the same, a form in which the whole is linearly inclined is obtained. If the angle between the chord 1 and the bundle 4 of each minimum unit truss 10a is arbitrarily changed, a truss frame bent in a polygonal manner can be formed.
[0004]
[Problems to be solved by the invention]
However, in the former variable-truss frame structure disclosed in Japanese Patent Application Laid-Open No. 4-146352, the upper-limit minimum unit truss formed of a triangular shape with the upper chord material and two diagonal members has a fixed shape. In order to change the shape of the truss frame as a whole, the length of the lower chord of the variable length is expanded and contracted to change the shape of the minimum unit truss on the lower chord side that is formed into a triangle including this lower chord. Therefore, the degree of correspondence to various shapes was low. In addition, considering the application to openable roofs and transporting trusses, it is necessary to fold the truss small, but since the minimum unit truss on the upper chord side can not change shape, it is possible to fold the entire truss frame small. It was difficult to store in a limited space.
[0005]
On the other hand, in the latter truss frame structure in which parallelogram truss lattices are connected like the truss structure of FIG. 6 disclosed in Japanese Utility Model Application Laid-Open No. 63-200910, all the chord members and the bundle members are always parallel. Therefore, if the overall configuration of the truss frame is to be set to an arc shape as shown in FIG. 7 in particular, the minimum unit truss 7a on the fixed side of the base end of the truss frame extends from the tip end along the arc. The degree of deformation of each minimum unit truss 7a must be gradually increased over the minimum unit truss 7a on the side, and when the distal end side is bent to 90 degrees with respect to the base end side, the minimum unit truss 7a at the distal end is bent. The parallelogram formed is such that the chord 1, the bundle 4, and the diagonal 5 overlap almost linearly and extend, losing the function of dispersing and supporting the original load of the truss, and the strength is extremely reduced. Defect is raw That. Further, the minimum unit truss 7a at the distal end cannot be bent by 90 ° or more with respect to the base end, so that there is a restriction that the truss frame can be formed only up to a quarter arc.
[0006]
The present invention has been made in view of the above problems, and an object of the present invention is to provide a shape-variable truss frame that can cope with various shapes without impairing the structural strength of the truss and that can be folded small. It is in.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, a pair of chord members and a pair of bundle members are rotatably connected to each other to form a quadrangular lattice, and along one diagonal line. A variable-length diagonal member whose expansion and contraction is adjustable is rotatably connected between both nodes to form a minimum unit truss as a basic element, and the minimum unit trusses are connected in a ladder shape while sharing a bundle. In a variable-truss truss frame that can be changed in shape by arbitrarily adjusting the length of the diagonal members, a pair of chord members and a pair of bundle members that constitute the minimum unit truss are provided. The length of at least one of the pair of chords is configured to be adjustable to an arbitrary length in order to change the shape while maintaining a sufficient separation distance .
[0008]
According to the above configuration, since one of the pair of chords constituting the minimum unit truss of the quadrilateral serving as the basic element can be adjusted to extend and contract, the lengths of the two chords forming the pair differ from each other. The minimum unit truss can be formed into an arbitrary quadrilateral shape or trapezoidal shape in which the two chord members and the bundle members are sufficiently separated from each other by adjusting the length of the diagonal members accordingly. For this reason, sufficient strength can be secured by dispersing the load throughout the truss frame, and the angle between the chord material and the bundle material can be continuously changed, so that it can cope with various shape changes while maintaining strength As a result, the degree of freedom in changing the shape is increased as much as possible.
[0009]
Also, if the length of the two chords is equal, the lattice shape of each minimum unit truss is a parallelogram, and if the diagonal is stretched to the maximum, the chord, diagonal, and bundle are aligned almost straight. And can be folded as small as possible.
[0010]
According to a second aspect of the present invention, a variable length truss member and a fixed length truss member that can be extended and contracted are used for a pair of chords constituting the minimum unit truss, and the minimum unit truss is framed in a ladder shape. In this state, the variable length truss members and the fixed length truss members are alternately arranged.
[0011]
With this configuration, when forming a curved truss frame, the variable length truss member inside the curve is extended, while the variable length truss member outside the curve is contracted, so that the variable length truss member is continuously arranged on one side. In comparison, if the curvature can be made large, or if the curvature is made the same, the amount of expansion and contraction of each variable length truss can be reduced.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a deformable truss frame according to the present invention will be described in detail by taking an embodiment shown in the accompanying drawings as an example.
[0013]
FIG. 2 is a schematic configuration diagram in the case where the deformable truss frame of the present invention is applied to a cantilever beam, and FIG. 2A is a side view showing a basic form which is a reference of the entire form of the frame. (b) is a side view showing a minimum unit truss as a basic element forming one lattice portion of the truss frame. As shown in FIGS. 2A and 2B, the deformable truss frame 10 of the present invention is formed by connecting a large number of minimum unit trusses 10a as basic elements. The pair of chords 1a, 1b and the pair of bundles 4, 4 are rotatably connected to each other via a pin joint 3 to form a quadrilateral lattice, and one of the lattices One diagonally adjustable diagonal member 5 composed of a variable length truss member 5a via the pin joint 3 is provided between the joints between the chord members 1a and 1b and the bundle members 4 and 4 along the diagonal line. It has a structure in which a variable length truss member 1b similar to the diagonal member 5 is used for at least one of the chord members 1a and 1b. Here, in the present embodiment, the variable length truss member 1b is used for one of the pair of chord members 1a and 1b, and the fixed length truss member 1a is used for the other.
[0014]
The variable-shaped truss frame 10 is formed by connecting and linking a large number of the minimum unit trusses 10a in a ladder shape in one direction while sharing the bundle 4 in a ladder shape, as shown in FIG. As shown in (1), the form extending in a straight line is the basic shape. Here, in the present embodiment, a plurality of minimum unit trusses 10a are connected by alternately arranging the stretchable variable-length truss members 1b and the non-stretchable fixed-length truss members 1a in the string members 1a and 1b. ing. Also, the diagonal members 5 are alternately arranged for each of the adjacent minimum unit trusses 10a along two diagonal directions.
[0015]
In the variable shape truss frame 10 having the above configuration, the length of the variable length truss member 1b of the pair of chord members 1a and 1b in each minimum unit truss 10a is set to be the same as the length of the fixed length truss member 1a. Then, it becomes almost the same as the conventional truss frame. That is, when the length of the variable length truss member 5a of the diagonal member 5 is adjusted and the chord members 1a, 1b and the bundle member 4 are set at right angles, the lattice of each minimum unit truss 10a has a rectangular shape or a rectangular shape. The overall configuration of the truss frame 10 has a basic shape that extends linearly and almost horizontally. When the length of the diagonal member 5 is adjusted and the lattice of each minimum unit truss 10a is set to a parallelogram having the same angle, the overall shape becomes a linearly inclined shape. Furthermore, if the lattice of each minimum unit truss 10a is set to a parallelogram of an arbitrary angle, the overall form will be a polygonally bent shape.
[0016]
By the way, in the truss frame 10 of the present invention, the variable length truss members 1b and 5a which can be extended and contracted to at least one of the two chord members 11a and 1b constituting the minimum unit truss 10a and the oblique member 5 are used. Therefore, the minimum unit truss 10a can be formed in a quadrilateral as shown in FIG. 2C by changing the mutual length of the two chord members 1a and 1b, and the length of the diagonal member 5 is also reduced. By adjusting together, a trapezoid or a shape very close to this can be formed.
[0017]
That is, by adjusting the length of the chord 1 made of the variable-length truss member 1b so as to be longer or shorter than the chord 1 made of the fixed-length truss 1a, the two chords 1a and 1b are adjusted. Can be continuously and arbitrarily changed while the chords 1a and 1b and the bundle 4 are kept sufficiently apart from each other. As described above, the shape of the lattice formed by each minimum unit truss 10a is adjusted so that the four angles are respectively set while keeping a sufficient distance between the pair of chord members 1a and 1b and the pair of bundle members 4 and 4. By adopting a different arbitrary quadrilateral shape or trapezoidal shape, it becomes possible to disperse the load over the entire truss frame 10 and secure sufficient strength. Therefore, while maintaining the strength, for example, FIGS. As shown in (f), the shape of the truss frame 10 can be changed with a high degree of freedom.
[0018]
In particular, in the variable-shape truss frame 10 of the present embodiment, the lattice shape of the minimum unit truss 10a can be set to a trapezoidal shape or a shape that is very close to the trapezoidal shape. As shown in FIGS. 3 and 4, the strings 1a and 1b and the bundles 4 and 4 can be curved while being sufficiently separated from each other, and the lattice of the minimum unit truss 10a on the distal end side can be formed. The shape is not crushed in a straight line as in the prior art, a sufficient strength can be secured even if the central angle of curvature exceeds 90 degrees, and it can be formed in a semicircular arc or annular shape.
[0019]
In addition, while the chord 1 made of the variable length truss member 1b arranged on the inside in the bending direction is contracted, the chord 1 made of the variable length truss member 1b arranged on the outside in the bending direction is elongated, thereby increasing the curvature and curving. It can also be formed, and a high degree of correspondence can be obtained with respect to the magnitude of the curvature. In particular, if the bundle 4 is arranged in the normal direction of the desired virtual arc to be formed, the interval between the two chords 1a and 1b is maximized, which is extremely effective in securing the strength of the truss frame 10.
[0020]
In addition, in consideration of application to an openable roof, transportation of a truss frame, and the like, it is necessary to fold the small truss structure. Since it is possible to store it in a small space, it is possible to efficiently store it in a limited space and to have excellent transportability. Easy and efficient. Further, when the minimum unit truss 10a is expanded from the folded state to expand the truss frame, the setting of the expansion and contraction ratio of each of the expandable and contractible truss members 5b and 1b is appropriately changed individually as shown in FIGS. A complicated shape can also be easily formed as shown in FIG. Further, as shown in FIG. 3, the base end side is fixed to the ground or the like, and the present invention can be applied to a semi-circular or semi-cylindrical openable roof.
[0021]
In the above description, the truss frame 10 in which the minimum unit trusses 10a are continuously arranged in one direction has been described as a basic example. However, a large number of the truss frames 10 are arranged side by side (in the paper direction) and connected. Thereby, a truss frame having a three-dimensional structure can be formed.
[0022]
Further, in the above-described embodiment, an example is shown in which the variable length truss members 1b and the fixed length truss members 1a which can be extended and contracted are used for the chord members 1a and 1b, and these are alternately connected. The bending performance and the bending performance in the lower chord direction are considered so as to be equivalent. When it is not necessary to make the bending performance equivalent, the arrangement of the chord members 1a and 1b is not limited to this, and the minimum One of the two chords 1a and 1b constituting the unit truss 10a is only required to be extendable and contractible. For example, as shown in FIG. It is possible to obtain the same effect by arranging them separately on the lower string side, or by arranging them irregularly.
[0023]
【The invention's effect】
As described above, according to the shape-variable truss frame according to the present invention, one of the pair of chord members constituting the minimum unit truss of a quadrilateral serving as a basic element can be adjusted in expansion and contraction, so that a pair is formed. By setting the lengths of the two chords different from each other, and adjusting the length of the diagonal members accordingly, the individual minimum unit trusses are separated sufficiently from the two chords and the bundle. Can be formed in any desired quadrilateral or trapezoidal shape, and the angle between the chord and the bundle can be continuously changed, so that the adjacent minimum unit truss can be bent at various angles, and In addition to being able to form the entire form of the truss frame corresponding to various shapes, the load applied to the truss frame can be dispersed, and the structural strength of the truss frame can be sufficiently ensured.
[0024]
Further, if necessary, it can be folded into a small space and can be folded well, so that it can be efficiently stored in a limited space, and also has excellent transportability. Further, in expanding the truss frame into a desired form by extending the folded state, the truss members can be easily formed into various shapes by appropriately changing the expansion ratio of each truss member of the stretchable string member and the diagonal member. It can be formed and is very effective for application to openable roofs and the like.
[0025]
Also, a pair of chords constituting the minimum unit truss, using a variable length truss member and a fixed length truss member that can be extended and contracted, and a variable length truss member in a state where many of the minimum unit trusses are framed in a ladder shape. If the fixed truss members are arranged alternately, the variable truss members inside the curve can be stretched while the variable length truss members outside the curve can be contracted when the truss frame is curved. The curvature can be made larger than when the long truss members are arranged in series, or if the curvature is made the same, the amount of expansion and contraction of each variable length truss can be reduced.
[Brief description of the drawings]
FIG. 1 is a view showing various shape modifications of a variable shape truss frame according to a first embodiment of the present invention.
FIG. 2 is a schematic configuration diagram of a variable-shape truss frame according to a first embodiment of the present invention. FIG. 2 (a) is a side view showing a basic form serving as a reference of the overall form of the frame, and FIG. FIG. 2 is a side view showing a minimum unit truss as a basic element forming one lattice part of the truss frame. FIG. 2C is a side view showing an example of a state where the minimum unit truss is deformed.
FIG. 3 is a view showing a second embodiment of the variable shape truss frame of the present invention.
FIG. 4 is a partially enlarged view of FIG. 3;
FIG. 5 is a view showing a third embodiment of the variable shape truss structure of the present invention.
FIG. 6 is a schematic configuration diagram showing an example of a conventional variable shape truss frame.
FIG. 7 is a view showing a case where the shape-variable truss frame of FIG. 6 is curved in an arc shape.
FIG. 8 is a partially enlarged view of FIG. 7;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 String material 1a Fixed length truss chord material 1b Variable length truss chord material 2 Joining material 3 Universal joint 4 Bundle material 5 Diagonal material 5b Variable length truss diagonal material 7a Minimum unit truss 10 Truss frame 10a Minimum unit truss

Claims

一対の弦材と一対の束材とを回動自在に結合して四辺形の格子状に形成するとともに、一方の対角線に沿って両節点間に伸縮調節可能な可変長の斜材を回動自在に結合させて、基本要素となる最小単位トラスを構成し、該最小単位トラスを、束材を共有させつつ多数梯子状に連設して骨組みし、該斜材の長さをそれぞれ任意に調節することで形状変更可能となした形状可変トラス架構において、
前記最小単位トラスを構成する一対の弦材相互並びに一対の束材相互の離間距離を十分に保たせながら形状変更すべく、前記一対の弦材のうち少なくとも一方を任意の長さに伸縮調節可能にしたことを特徴とする形状可変トラス架構。A pair of chords and a pair of bundles are rotatably connected to form a quadrilateral lattice, and a variable-length diagonal member that can be stretched between two nodes along one diagonal is rotated. The minimum unit truss can be freely combined to form a basic unit, and the minimum unit truss can be connected in a ladder-like fashion while sharing a bundle, and can be arbitrarily lengthened. In a shape-changeable truss frame that can be changed in shape by adjusting,
At least one of the pair of chords can be adjusted to an arbitrary length so as to change the shape while maintaining a sufficient distance between the pair of chords and the pair of bundles constituting the minimum unit truss. A shape-changeable truss frame characterized by:

前記最小単位トラスを構成する一対の弦材に、伸縮調整可能な可変長トラス部材と固定長トラス部材とを用い、該最小単位トラスを多数梯子状に骨組みした状態で該可変長トラス部材と固定長トラス部材とを交互に配置したことを特徴とする請求項１記載の形状可変トラス架構。A pair of chords constituting the minimum unit truss, using a variable length truss member and a fixed length truss member that can be stretched and adjusted, and fixed to the variable length truss member in a state where the minimum unit truss is framed in a ladder shape. 2. The variable shape truss frame according to claim 1, wherein the long truss members are alternately arranged.