Technical Field

The invention relates to the field of wide span, self-supporting frame structures which can be rapidly erected and collapsed.

Background Art

Various self-erecting frame structures are known in the art. Canvas or nylon tents, for example, provide portable self-supporting structures which can be readily erected or collapsed for transport. Some applications however require structures of much larger dimension than standard tents, or able to support much larger loads. More substantial structures have been developed to meet such needs. For example, Great Britain Complete Specification no. 941466 discloses a flexible load-supporting structure formed of a number of arched ribs supporting a covering. The ribs are formed from flexibly connected blocks which can be rolled up in one direction but form a rigid arch when tensioned in the opposite direction. GB 2167783A dis¬ closes a frame structure having trusses of tubular steel forming upper and lower chords, with a tensioning cable running through the lower chord to allow post-tensioning of the truss to the desired shape. Columns are hingedly connected on either end of the central span with additional cables provided to raise the central span above such columns when the cables are tensioned. GB 2254630A dis¬ closes an arched structure having hingedly connected segments with a tensioning cable running below each segment to raise the structure when the cable is tensioned by a winch. U.S. patent no. 3,057,119 Kessler discloses a method of constructing a structural arch by starting with a flat flexible sheet and applying tension to either edge to draw it into an arch. U.S. patent no. 5,159,790 Harding dis¬ closes a frame structure which can be moved from a col¬ lapsed to an erected condition. It comprises a number of

frame arches, each comprising a number of rigid frame sections hingedly connected end-to-end. Cables running below the frame sections are tensioned to raise the struc¬ ture into an erected position on support legs.

In the past, large collapsible covered structures have been too cumbersome when disassembled to be readily transportable. There is therefore a need for a covered frame structure which is readily erected and collapsed and is large enough to span a wide area.

Disclosure of Invention

The present invention provides a covered self- supporting structure which comprises a plurality of spaced arches with a fabric cover tensioned over the arches. Each arch consists of a number of rigid frame sections which are joined end to end. In each frame section the top chord is longer than the bottom chord. The top chords of adjacent frame sections are pinned together to allow the frame sections to rotate about the common joint. The bottom chords are connected by a joint assembly, comprising a spacer, guide plates, a locking mechanism and joint fit¬ tings. This joint assembly allows the ends of the bottom chord to travel a limited distance towards or away from each other. Endframes are joined to the end of each arch. A wheel or ski is mounted on one endframe of each arch. A device such as a winch is mounted on the other endframe of each arch. A cable is attached to the winch, extending across the width of the structure along the ground and is attached to the opposite endframe. To provide more mechan¬ ical advantage in the early stages of the erection process, the winched cable may go through a multiple-pulley arrange¬ ment, like a block-and-tackle, attached by cable to the opposite end of the arch. The arches are connected to one another with bracing members.

The structure is assembled flat on the ground. Each arch is formed by connecting the support frames, rigid

frame sections and bottom joint assemblies. The arches are joined together with the bracing components. The frame¬ work, cover and endwalls are attached to this structure and tensioned. To erect the structure, each cable is tensioned by each winch, causing the ends of each arch to be brought together and forcing the building into its erected arched form. As the arches raise, the ends of adjacent bottom chords move towards each other. Once the bottom joints have reached the extent of their travel, they are locked in place with a locking mechanism, which prevents the joints from spreading apart. After the building is fully erected and the bottom joints are locked off, it is anchored securely to the ground and the cable is removed and stored. Finally the weather seals on the cover and endwall are secured.

Brief Description of Drawings

In drawings which illustrate a preferred embodi¬ ment of the invention:

Fig. 1 is a perspective view, partially cut away of the invention in the erected state;

Fig. 2 is an elevation of a frame section for a 50-foot span structure according to the invention in the erected state;

Fig. 3 is a detail of a truss section according to the invention;

Fig. 4 is a detail of the clevis pin and bridging point structure for a truss section;

Fig. 5 is a detail of two truss sections during erection;

Fig. 6 is a detail of a male endframe according to the invention; Fig. 7 is a detail of a female endframe according to the invention;

Fig. 8A and 8B are top and side views of the base plate assembly;

Fig. 9A and 9B are details of a joint assembly according to the invention, in side and top view; Fig. 10 is a side view of the winch support of the invention, partially exploded;

Fig. 11 is a plan view of a standard cover panel according to the invention;

Fig. 12 is a plan view of an end cover panel according to the invention;

Fig. 13 is a detail of the end cover panel of Fig. 12;

Fig. 14 is a detail of the standard cover panel of Fig. 11; Fig. 15 is a detail of the cover connection flap;

Fig. 16 is a detail of the weatherseal flap; Fig. 17 is a detail of the single edge side of the standard panel shown in Fig. 11;

Fig. 18 is a plan view of an end connecting rod Fig. 19 is a plan view of a standard insulating panel according to the invention; and

Fig. 20 is a plan view of an end insulating panel according to the invention.

Best Mode(s) For Carrying Out the Invention

Fig. 1 illustrates the structure 10 according to the invention in erected condition, with the fabric cover 12 partially cut away to reveal parallel supporting frame- work arches 14 joined by bracing purlins 16 of rigid tubular steel. The building is designed for widths of 50 feet (15.3 m.), 70 feet (21.3 m.) , 100 feet (30.5 .), 125 feet (38.1 m.) or 150 feet (45.7 m.) with a minimum pre¬ ferred length of 60 feet (18.3 m.) expandable indefinitely in 12 foot (3.7 m.) increments. It is collapsible and breaks down into components of 12 feet (3.7 m.) or less. End panel 18 is provided with a configuration of doors 20,

22 according to the desired application, whether as emerg¬ ency shelter for humans, as a warehouse or a rapidly deployed aircraft or vehicle cover.

As illustrated in Fig. 2 and 3, each supporting framework arch consists of a number of rigid frame sections or trusses 24, each preferably 12 feet (3.7 m.) long, which are joined end to end. The top chord 26 of each truss 24 is longer than the bottom chord 28. Top and bottom chords 26, 28 are preferably 3" x 2" (7.6 cm. x 5.1 cm.) galvanized steel and are joined by web members 30 of 1" x 1" (2.5 cm. x 2.5 cm.) galvanized steel. One end of each top and bottom chord 26, 28 is provided with a female clevis casting 32 while the opposite end of each top and bottom chord 26, 28 is provided with a male clevis casting 34. The top chords of adjacent frame sections are pinned together at 36 to allow the frame sections to rotate about the common joint 36.

The bottom chords 28 are connected by a joint assembly 38 shown in Fig. 8 and 9. Joint assembly 38 com- prises a spacer 40, two guide plates 42 each having a slot

43, female clevis 44 and male clevis 46. Female clevis 44 and male clevis 46 are pinned to male clevis 34 and female clevis 32 of adjoining bottom chords 28 to form joint assembly 38. The joint assembly 38 allows the ends of the bottom chords 28 to travel a limited distance towards or away from each other. As illustrated in Fig. 5, as trusses 24 are rotated downwardly about joint 36, pinned clevises

44, 34 slide along slots 43 until the pin abuts the right end of slot 43. A locking mechanism is provided for the joint assemblies on the first row of truss joints from the ground to lock the first row of joints when erected. The locking mechanism for example can be a spring-operated latch which is pivotally mounted on clevis 44 and snaps over end 32 when the trusses are in the position shown in Fig. 5.

Each end of each arch section 14 is provided with a male or female endframe, 47, 48 shown in Fig. 6 and 7.

Male endframe 47 has two male clevis castings 49, a hollow top member 51 and a diagonal member 53. Extension 55 slides in top member 51 and is secured at a selected extension by a pin through holes 57, 59. The baseplate assembly 60 shown in Fig. 8 pins into hole 62. Female endframe 48 has male clevis casting 49, female clevis castings 58, a hollow top member 61 and a diagonal member 63. Extension 65 slides in top member 61 and is secured at a selected extension by a pin through holes 67, 69. The baseplate assembly 60 shown in Fig. 8 pins into hole 62. Male endframes 47 are joined to the end of each arch 14 at female clevises 32, and female endframes 48 are joined to the end of each arch 14 at female clevises 32 and male clevises 34. Each endframe has four chain links or loops 68 (two on each side) to which the cover 12 can be tighte¬ ned and to which erection cables can be attached.

The baseplate assembly 60 shown in Fig. 8 con¬ sists of a bracket 71 with hole 73 for pinning to hole 62 on the endframes. Bracket 71 is welded to base plate 75, as is a winch 77. Base plate 75 has a slot 79 such that the drum 78 of winch 77 is centred over slot 79. Ground anchors are installed under slots 79 with a cable running to winch 77 to allow the endframes to be tightened to ground anchors after erection. A wheel 50 or ski (not shown) is mounted on one endframe 47 at holes 52. A device such as a winch 81 is mounted on the other endframe 48 at holes 54 by a winch support 74, shown in Fig. 10. Preferably winch 81 is a 2500 lb. capacity hand winch which is bolted to winch support 74 through holes therein by screws 80, washers 90 and locknuts 92. Support 74 is a hollow rectangular steel bar with an end flange 96 and a further chain link or loop 94 to which a cable can be connected or through which a cable can be threaded. A hinged pulley can be connected in connection with loop 94 to facilitate the direction of the erection cable. Support 74 is secured to an endframe 47,

48 through holes 98 and 54 by inserting support 74 through the hollow formed between parallel plates 63 ^■ , 53 ' .

A cable (not shown) is attached to the winch 81, extending across the width of the structure along the ground between the endframes of each arch 14 and is at¬ tached to the opposite endframe at chain links 68. Prefer¬ ably, the cable goes through a series of pulleys connected to the opposite endframe to provide increased mechanical advantage. Adjacent parallel arches are connected to one another by bracing cables 16 which are steel tubing drilled through their ends to secure to clevis pins 84 (Fig. 3, 4 and 6) . Bridging cables (not shown) also run between upper clevis pin 86 on one arch section and the corresponding lower clevis pin 88 on the joint assembly 38 of the adjac¬ ent arch section. Since the distance between points 86 and 88 increases as the structure is erected, the bridging cables serve to tension the assembly.

The cover assembly 12 is constructed generally from vinyl, preferably 21 oz. weight. The cover is formed of panels 12 feet (3.7 m.) wide and 95 feet (29.0 m.) or 71 feet (21.6 m.) for the 70 foot (21.3 m.) and 50 foot (15.3 m.) widths respectively. The cover utilizes two types of panels, a standard panel 100 shown in Fig. 11 and an end panel 102 shown in Fig. 12. The standard panel 100 has a triple edge side 104 and a single edge side 106 and panel ends 108. Both edges of the end panel 102 are triple edge sides 104.

The construction of the panel ends 108 is shown in greater detail in Fig. 13. A 6-inch (15.2 cm.) pocket 110 is formed by folding the ends and double-stitching at 114. Two 4-inch (10.2 cm.) cut-outs 112 are formed in the pockets 110. The frame connection edge 116 of each panel has a 4-inch (10.2 cm.) pocket 117 formed by folding the edge and double-stitching at 118. A plurality of 3-inch (7.6 cm.) cut-outs 120 are regularly spaced along edges 116. The triple edge sides 104, shown in detail in Fig.

14, are formed by welding a cover connection flap 122 (shown in phantom outline in Fig. 14) and a weatherseal flap 124 to the main cover panel 100. Cover connection flap 122, shown in Fig. 15 is welded to cover panel 100 along line 123 and weatherseal flap 124, shown in Fig. 16, is welded to cover panel 100 along line 125. The cover connection flap 122 has a 4-inch (10.2 cm.) pocket 126 formed by folding the edge and double-stitching along line 127. 3-inch (7.6 cm.) square cut-outs 130 are formed at each end and a plurality of 3-inch (7.6 cm.) by 20 inch

(50.8 cm.) cut-outs 132 are formed every 36 inches 91.4 cm.) on center along the length of the flap starting 30 inches (76.2 cm.) from each end. The weatherseal flap 124 has a 2-inch (5.1 cm.) pocket formed by folding the edge and double-stitching along line 135, and a wire rope (not shown) is inserted in pocket 134 to hold, when tightened, the weatherseal flap 124 tight against the cover 12. The female half 140 of a FASTEX™ buckle is fastened on one side of the panel, with the corresponding male halves 141 attached to the main panels 100. Buckles 140 are not provided on the second triple edge 104 ' of the end panels 102. The single edge side 106 of panel 100 is shown in Fig. 17. A 4-inch (10.2 cm.) pocket 144 is formed by line 145 of double stitching. A plurality of 3-inch (7.6 cm.) by 20 inch (50.8 cm.) cut-outs 146 are formed every 36 inches (91.4 cm.) on center along the length of the flap starting 12 inches (76.2 cm.) from each end. Reinforcement patches 150 are attached 8.5 inches (21.6 cm.) on center in from the edge 106 every 12 feet (3.66 m.) on center beginning 11.5 feet (3.5 m.) from an end.

To construct the cover 12, starting at one end with an end panel 102, edge 106 of a panel 100 is inter¬ locked with edge 104 of three adjoining panel in a tongue- and-groove type of arrangement, and a series of 11.5 foot (3.5 m.) long, l/2-inch (1.3 cm.) diameter aluminum rods (not shown) are sleeved through the pockets 122, 144 to join the adjoining cover sections. Through each frame

connection edge 116 another series of 11.5 foot (3.5 m.) long, 1/2-inch (1.3 cm.) diameter aluminum rods (not shown) are sleeved through the pockets 117. Along each end 108 of each panel 100, 102, a 10.5 foot (3.2 m.) long, 1/2-inch (1.3 cm.) diameter steel rod 152 shown in Fig. 18 is sleeved through the pockets 110. Each rod 152 has two welded loops or chain links 154.

To attach the cover 12 to the arch sections 14, the rods in pockets 117 of frame connection edges 116 are strapped to the top chords 26 of trusses 24 using polyester web belts every 3 feet (.91 m.) with buckles for tightening

(not shown) . Rods 152 are tightened to endframes 47, 48 by means of web straps with ratchet assemblies run through loops 154 and connected at either end to endframes to tighten the cover panels longitudinally.

An insulated cover, made of POLYTHERM™ or REF- LECTIX™ material stitched to a layer of material such s vinyl, may be attached to the interior side of the cover 12 as follows. The insulated cover is formed of standard panels 160 shown in Fig. 19, which are 12.25 feet (3.7 m. ) wide and 71 feet (21.6 m.) long for the 50 foot (15.3 m.) span and 95 feet (30 m.) long for the 70 foot (21.3 m.) span, and end panels 162 shown in Fig. 20 which are 11.5 feet (3.5 m.) wide and the same length as the standard panels. Each side of the insulation panels is provided with webbing/ring assemblies 164 which are spaced 3 feet

(.9 m.) apart on sides 165, starting 1 foot (.3 m.) from each end, and 4.5 feet (1.4 m.) apart, starting 3 inches

(7.6 cm.) from each end on side 167. The ring/ebbing assemblies are formed by stitching a 1.5 inch (3.8 cm.) diameter steel ring to the backing by a 1 inch (2.5 cm.) strip of webbing through the ring. The standard panel 160 also has a 6-inch (15.2 cm.) wide reinforcement strip 168 attached. The insulated cover is aligned with the cover sections 100, 102 when the cover is assembled and the aluminum rods are threaded through the ring assemblies 164 as the cover sections are being joined.

The structure 10 is assembled flat on the ground. Each arch section 14 is formed by connecting the trusses end to end at 36 and at joint assemblies 38, and connecting the endframes 47, 48 to the ends of sections 14. The arch sections are joined together with the bracing components. To this structure the assembled cover 12 and endwalls 18 are attached and tensioned. To erect the structure, each erection cable is tensioned by the winches 81, causing the ends of the arches to be brought together and forcing the building into its erected arched form. As the arches raise, the ends of adjacent bottom chords move towards each other. Once the bottom joints have reached the extent of their travel, they are locked in place with the locking mechanism, which prevents the joints from spreading apart. After the building is fully erected and the bottom joints are locked off, ground anchors such as duckbill anchors are installed and the base plates at the end of each arch are tightened to the anchor using cable and winches 77. After the structure is anchored securely to the ground and the erection cable is removed and stored. Finally the weather seals on the cover and endwalls are secured. The endwalls maybe hinged to allow for freedom of movement.

As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the spirit or scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the substance defined by the following claims.