Arrangement for a collapsible frame and similar structures

Technical field:

The present invention relates to an arrangement in the form of a collapsible frame and similar structures, incorporating an articulated arrangement for rearranging two constituent elements of the frame between a storage position and an erected operating position, said articulated arrangement incorporating an articulated joint by means of which the two constituent elements of the frame are flexibly connected to each other-

Background:

Conventional collapsible frames exhibit articulated arrangements which usually consist of a simple hinged joint between constituent elements of the frame, said joints being designed to be collapsed_bybending- In order to achieve a distinct end position when the constituent elements of the frame are extended, it has been necessary to provide these with special clamps or similar arrangements- This means that two separate operations must be performed when erecting or collapsing the frame, i.e. operating the clamp and rearranging the two constituent elements of the frame to a point between their end positions- The use of the clamp also involves increased costs for the articulated arrangement- Furthermore, the clamp is so positioned that it is capable in the frames for tents and similar structures of causing wear and damage to the tent canvas- In certain applications, the clamp may also be subject to the ingress of dirt and to the effect of the weather, which requires maintenance to be provided if its function is to be assured.

The object of the present invention is to propose an arrangement in which the aforementioned disadvantages are eliminated.

The solution:

The aforementioned object may be achieved by means of an arrangement in accordance with the invention, which is characterized in that the articulated arrangement exhibits a male component connected to one of the constituent elements of th~ frame and a female component connected to the other constituent element of the frame, with both the male component and the female component exhibiting a cross—section which reduces from their outer end, whereby the form of the female component corresponds essentially to the form of the male component, with the male component and the female component being designed to interact so as to maintain the two constituent elements of the frame in a stable relationship with each other when in the erected position-

Brief description of drawings :

The invention will now be described below in greater detail in relation to a number of preferred embodiments with reference to the accompanying drawings, in which Fig- 1 shows an example of a frame fitted with an_ articulated arrangement in accordance with the invention; Fig- 2 and Fig- 3 show a diagrammatic view of the frame in accordance with Fig- 1 in its collapsed position; Fig- 4 and Fig- 5 show two different views of the articulated arrangement in accordance with the invention in a first embodiment in an open position, whilst Fig- 6 shows the articulated arrangement in a CQllapsed osition.Fig- 7 shows the articulated arrangement in a second embodiment. Figs- 8, 9 and 10 show the articulated arrangement in a third embodiment. Fig- 11 shows an example of a protective tent in a second embodiment, in which the articulated arrangement in accordance with the invention may be included, and Fig. 12 shows the frame for the protective tent in accordance with Fig- 11; Fig- 13 and Fig- 14 show the protective tent in accordance with Fig. 11 partly folded down and fully folded down. Figs. 15, 16 and 17 show in diagrammatic form certain component parts of the protective tent in accordance with Fig. 11 in its collapsed position- Figs- 18 and 19 show on a larger scale

a connecting arrangement for the protective tent in accordance with Fig. 11, whilst Figs. 20 and 21 show a further connecting link which forms part of the frame. Fig. 22 shows the frame collapsed with the connecting link in accordance with Figs. 20 and 21- Fig. 23 shows an example of a modified frame for the protective tent of the type illustrated in Fig. 11.

Best mode of carrying our the invention:

The frame 1 shown in Figs. 1, 2 and 3 consists of a number, being five in the example shown, of frame rails 2 which are flexibly connected to each other by means of two central hinged joints 3 - The frame rails are intended to support a tent canvas 4 , which is shown in diagrammatic form as dotted and dashed lines. The tent canvas may exhibit openings (not shown) providing an entrance for example. The frame rails 2 are connected to each other by means of a number of stays 5 . Each individual stay is connected at its ends to the appropriate frame rail by means of a connecting link 6 . At the centre of the stay is arranged an articulated arrangement 7 in accordance with the invention, which is protected by means of an elastic protective sleeve 8 . Each individual frame rail 2 is also capable of being collapsed by means of an articulted arrangement 9 in accordance with the invention, which is situated at the top of the side piece 10 of every, frame rail 2 . In the example shown, three of the frame rails 2 are equipped with a framework construction on their top pieces 11 . The two frame rails 2 which are lying on the ground exhibit reinforcement plates 12, 13 at their corners, of which at least one plate on each frame rail exhibits holes 14 for anchoring pins intended to -anchor the frame to a base, for example the ground. For the purpose of providing anchorage, the two central hinged joints 3 are equipped with anchorage plates 14 . The hinged points exhibit a total of five pivot points 15, 16 , representing one pivot point for each frame rail 2 , with one of said pivot points 16 also forming the connecting link for the two halves 17, 18 of the hingedi joint.

Figs. 2 and 3 show the frame 1 in diagrammatic form in its collapsed state- The tent canvas is also shown here in the interests of clarity, said canvas being securely attached to each frame rail and thus being folded down together with the frame. The manner in which folding takes place is for the stays 5 to be folded by sideways pressure exerted on the articulated arrangement 7 , when the frame rails 2 can be folded up against each other by causing them to pjvot about their pivot points 15, 16 in the hinged joint 3 . Each individual frame rail 2 is then folded up by moving the two hinged joints 3 inwards. Fig. 2 illustrates in diagrammatic form the status of every individual frame rail 2 in its collapsed position, with the remaining frame rails being situated behind the rail illustrated and not being shown here in the interests of clarity. Fig. 3 shows that the two halves of the hinged joint 3 may be arranged thanks to their ability to pivot about the pivot point 16 in such a way that all the pivot points 15, 16 may be positioned essentially in Line with each other, which means that the articulated arrangements 9 will lie at the same height as the others, thus permitting every frame rail 2 to be folded. As may also be appreciated from Fig. 3, each of the articulated arrangements 9 is fitted with its own protective sleeve 19 made of rubber or a similar material. By means of the stays 5 all the rails 2 are imparted with the desired displacement such that their pivot points 9, 15, 16 lie at the same height as each other. In the example shown, this is achieved by causing the points at which the stays 5 fold, i.e. the connecting links 7 , to be situated at the centre of the stays, and by causing the ends of the stays to be attached at identical distances from the lower connecting links 15, 16 .

Fig- 4 shows the articulated arrangement 9 on a larger scale, with the protective sleeve 19 removed to show the execution of the articulated arrangement- The articulated arrangement 9 is thus intended to connect two constituent elements of the frame flexibly to each other, said elements in the example shown forming part of the side piece 10 of the frame rail 2 . The two constituent elements of the frame are designated

by the numbers 20, 21 . The two constituent elements of the frame may be in the form of square—section or 0—section light metal tubing. The two constituent parts of the frame 20, 21 are each fitted at the two ends 22, 23 illustrated with one half 24, 25 of the connecting link, which together form the articulated arrangement 9 . The two halves 24, 25 of the connecting link may each be manufactured from a length of light metal, for example aluminium or one of its alloys. These are connected to each other by means of a hinged arrangement in the form of a pivot pin 26 which extends through holes 27 in a number of attachment lugs 28, 29 which in the two halves 24, 25 of the connecting link engage with each other like forks. Each of the halves 24, 25 of the connecting link exhibits two cylindrical parts, an outer cylindrical part 30 with an external diameter which essentially corresponds to the external diameter of the constituent elements 20, 21 of the frame, and an inner cylindrical part 31 whose diameter essentially corresponds to, or is in practice slightly less than the internal diameter of the constituent elements of the frame. Thus, by means of the inner part 31 the halves 24, 25 of the connecting link are secured to the constituent elements 20, 21 of the frame, which are clamped securely around these parts 31 , for example by means of a pressing arrangement.

In accordance with the invention the two outer parts exhibit connecting arrangements in the form of a male component 32 which projects from the cylindrical part 30 , and a female component 33 which accordingly forms a recess in the second cylindrical part. The male component 32 and the female component 33 are executed with a double—curvature generated surface 34 of essentially cylindrical cross—section, of which the diameter reduces in a direction away from the front faces 35, 36 of the two cylindrical parts 30 , said front faces being intended when the articulated arrangement is in its connected state to be in contact with each other. Both the male component 32 and the female component 33 terminate in a plane end face 37, 38 . Also, both the male component 32 and the female component 33 exhibit plane guide surfaces 39, 40 , which are

essentially of the same size and are essentially parallel to each other. By executing the male component 32 and the female component 33 so as to have a very tight fit relative to each other, the presence of stabilizing friction can be achieved between the male component and the female component when the articulated arrangement 9 is in its connected state with the constituent elements of the frame 20, 21 in their operating position. This means that the constituent elements of the frame 20, 21 will have turned relative to each other about the pivot pin 26 from the folded, collapsed position illustrated in Figs. 4 and 5, when the male component 32 will have been introduced into the female component 33 until the point is reached at which the front faces 35, 36 of the halves 24, 25 of the connecting link are in contact with each other and at which the surfaces of the male component and the female component essentially come into contact with each other- By means of the male component and the . female component and the plane lateral surfaces 39, 40 a connection which exhibits great resistance to torsion is achieved, in which the lateral surfaces 39, 40 are capable of absorbing large torsional forces. The stresses present in the articulated arrangement 9 are thus absorbed not only by the pivot pin 26 , but also by the surfaces of the male component 32 and the female component 33 which. face each other, thereby producing a very stable connecting link. No arrangement to hold the constituent elements of the frame together in their operating position is required when the connecting links 9 are present in the rails 2 of a frame of the type illustrated in Figs. 1, 2 and 3.

With the frame in accordance with Fig. 1 in its open position, it is in principle not possible to push the hinged joint 3 inwards in the direction of the pivot pins 15, 16 , with the result that the side pieces 10 of the rails are unable to turn about the connecting links 9 relative to the top pieces 11 . This is attributable principally to the fact that the pivot pins 15, 16 will only permit the rails to turn in a single plane at the same time as the side pieces of the rails are facing in

different directions and the pivot pins 15, 16 of the hinged joint are facing essentially at right—angles to the pivot pin of the articulated joints, of which the orientation may be appreciated from Figs. 2 and 3.

In the example shown in Figs. 4, 5 and 6, the constituent elements of the frame 20, 21 are in line with each other, whilst Fig. 7 illustrates a variant in which the two constituent elements of the frame are set at a slight angle to each other, as in the case of the stay 5 in Fig. 1. Fig. 7 illustrates the articulated arrangement 7 used for folding up the stay 5 . The internal structure of the articulated arrangement 7 with its male component 32 and its' female component 33 is similar to the embodiment shown in Figs. 4—6, as a consequence of which no further details are required here, except to state that the axes of symmetry of the male component 32 and the female component 33 form a certain, identical angle to that of the appropriate constituent element of the frame or part of the stay 41, 42 . This angle is 8 in the example shown, which means that the angle between the parts of the stay will be 164°. The front faces 35, 36 of the link thus lie on a plane which divides the angle between the constituent elements of the stays 41, 42 equally. This means, in conjunction with the positioning of the pivot pin 26 and with the fact . that the tent canvas 4 is attempting to move the rails 3 together, that the stays 5 will be locked in that position, since the constituent elements of the stays 41, 42 will be retained in position under the effect of the tent canvas with their front faces 35, 36 forced against each other. Once the constituent elements of the stays 41, 42 have gone 'over—centre* during folding, i.e. once they have moved beyond the position in which they are in line with each other, the connecting links will attempt to adopt the position illustrated in Fig. 7. The connecting links are caused to bend by the apllication of lateral pressure, for example pressure exerted against th ^* e pivot pin 26 . In the case of Larger tents, this pressure may best be applied by means of a pole which is fitted at one end with a sideways—facing or hook—shaped element.

Figs. 8, 9 and 10 illustrate the articulated arrangement in accordance with the invention in a further typical embodiment in which the corresponding reference designations to those used for the first typical embodiment have been increased in numerical value by one hundred. Unlike the first embodiment, the male component 132 and the female component 133 exhibit guide surfaces 139, 140 executed in the form of grooves laid cross— ise to each other in the male component and strips Laid cross— ise to each other in the female component- The grooves thus form depressions in the generated surface 134 , whilst the strips form projections from the generated surface. The grooves and the strips exhibit the same cross—sectional form ^* and dimension. An equivalent function will be achieved if the strips are arranged in the male component and the grooves are arranged in the female component. In the case of this example in accordance with Figs. 8—10, however., the male component 132 and/or the female component 133 must be executed in a slightLy defor able material such as plastic, so as to permit the introduction of the strips 133 into the grooves 139 . The strips and the grooves are thus located in such a relationship to each other that, with the constituent elements of the frame 120, 121 in their operating position, i.e. with the articulated arrangement 109 in the position shown in Fig. 10, engagement will take place between the strips and the grooves. Also, the generated surface 134 of the male component is designed and dimensioned in such a way in relation to the female component 133 that the generated surface of the male component is forced against the female component in the course of the pivoting movement of the articulated arrangement until the point is reached at which the male component is fulLy introduced into the female component, thereby achieving excellent engagement and alignment. In this way the articulated arrangement is able to withstand high Stresses without unintentional articulation or deformation of some other kind. The pivot pin 126 is thus protected against harmful stresses and torsional forces. Dotted and dashed lines are used in Fig. 8 to indicate the path of the edge part 140 of the female component 133 at the point

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situated furthest from the pivot pin 126 , which may be taken as an indication that the generated surface of the male component will exert tower stress if the female component is in an intermediate position, thereby ensuring excellent engagement when the constituent elements of the frame are in their operating position. This embodiment may be regarded as an alternative to the connecting link 7 illustrated in Fig. 7 used for folding the stays 5, which will thus be in line with each other.

Fig- 11 shows a further example of a protective tent, which may be fitted with a number of articulated arrangements in accordance with the invention- The protective tent shown is a hangar for a helicopter 240 , which is shown in outline as dotted and dashed lines. In order to suit the shape of the helicopter, one end of the hangar is considerably higher and wider than the other end- The design of the hangar is such that the helicopter is able to have its rotor blades 241 situated outside the hangar, together with those raised parts of the helicopter which surround the rotor shafts. The hangar thus exhibits two openings 260 for these parts and a closable entrance opening 242 . The covering material 204 is divided up into a number of sections so as to make the hangar easily manageable and transportable in several units, as described below in greater detail. At the top the material exhibits a bridging, self-supporting part 244 with a number of stays which support the bridging part and which extend between two frame rails. This bridging part may be removed to permit the hangar to be opened.

Fig- 12 illustrates an example of the construction of the frame 202 for the hangar in accordance with Fig. 10. The frame is in principle constructed in the same way as the frame in accordance with Fig. 1 from a number of frame rails 202 , of which two lie on the ground where they may be anchored to the ground by means of anchor plates 213, 214 . The frame rails are also flexibly connected to each other by means of the central hinged joint 203 , which similarly exhibits anchor plates 214 . In this case, too, the hinged joint is divided into two halves which are able to articulate relative to each other. In this case.

however, the frame rails are six in number, in consequence of which two slightly oblique frame rails .are used in place of a single, fully upright frame rail. The frame rails are connected to each other by means of stays 205 which exhibit articulated arrangements 207 which may be of the type in accordance with the invention described above. Stays are disposed not only along the short sides, but also along the Long sides, and are so arranged as to bend when the frame is folded up. The top pieces 211 are of lattice construction and are in the form of a space—frame, consisting of three long tubular units which exhibit a large number of zig-zag stays 245 running from one to the other, as described in greater. detail below.

Fig- 13 shows the hangar in a partially folded position with the stays between the two outermost frame rails folded up so that the two frame rails lie against each other with the canvas material folded- This position may be adopted when the helicopter is to be made ready for take—off, and may even be maintained during take-off by the helicopter- Fig- 14 shows the hangar folded fully down with all the frame rails Lying against each other. This position is adopted when the tent is to be dismantled or inverted during the assembly phase.

Figs- 15, 16 and 17 show how the hangar is divided up into different sections- Fig- 15 shows the side pieces 210 of the frame rails 202 and the central hinged joint 203 . As may be appreciated from this view and from Fig. 16, the top pieces 211 of the frame rails in this example are connected to the side pieces by means of tubes 245 , which are passed- during assembly over the outer end 246 of the side pieces 210 of the frame rails. The canvas material 204 which is intended to cover the • gable pieces of the hangar is folded into a part 246 which is situated on the tubes 245 . The top pieces 211 of the hangar are also divided into sections which, in the example shown, are three in number. In this way a centre section 247 is produced which, by means of the associated canvas sections, is secured together with the remaining two centre sections to form a

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manageable unit 248 . The end sections 249 of the top piece are secured together to form a further unit. 250 , which is formed from three pieces of end sections.

A hangar in accordance with Fig. 11 is thus built up of two units 251 in accordance with Fig. 15, two units 248 of centre sections 247 and four units 250 of end sections 249 . All these units make the hangar easily manageable and transportable and take up comparatively little space during storage.

Figs- 18 and 19 show on a larger scale a connecting arrangement 252 for joining together the sections 247, 249 of the top piece. This connecting arrangement 252 exhibits two end plates 253 located at the end of the lattice structure in each section, with one of the end plates 253 exhibiting three holes directly in line with each of the three tubes 255, 256 . The end plate in the second section exhibits three stubs 257 which are intended to be inserted into the holes in the second end plate when the two sections are assembled together. Each centre section 247 exhibits one half of the connecting arrangement 252 , i.e. the end plate 254 with stubs 257 or with holes, whereas the end sections exhibit the other half of the connecting arrangement at one end.

Figs- 20, 21 and 22 show an alternative embodiment of the hinged joint, which in this case is designated by the reference 303 . In this example the hinged joint 303 consists of two long pairs of tracks 317, 318 , to which the rails 302 are flexibly attached by the pivot pins 315, 316 . The central pivot pin 316 also connects the rails together in a flexible fashion, in addition to which it forms the connecting link for the central, upright rail. One of the tracks 318 is connected in a flexible fashion at its outer end to a supporting element 361 , which is in the form of a U-shaped section and which is designed to rest by its bottom part 362 against a base. The other track 317 is so arranged thatit may be suspended by means of sideways—facing stubs 363 , which in this example constitute the ends of the pivot pin 315 , from an angular groove 364 on each of the two sides 365 of the support element 361 . The tensioning of the

tent canvas will cause the stubs 315 to be held in position in the groove when the frame is open.

It has been found that the support element 361 is not in any way necessary to the function of the hinged joint 303 , but that the pivoting of the tracks 317, 318 occurs under the effect of the stays 305 . The position of the attachment point of the stays to the rails 303 and the position of the pivot pins 307 of the stays (in the middle) in accordance with the invention has been selected so that the tracks 317, 318 with the frame in its collapsed state will be in line with each other, as will the pivot pins 315, 316 for the hinged joint 303 and the connecting links 9 .

The outer rails 303 , which are intended to rest on a base, exhibit in the example shown in Fig- 22 at least two anchorage eyes 366 , one on either side of the rail- These exhibit an anchorage hole 367 for a spike or similar hammered into the ground. The anchorage eyes 366 may, for example, be made from a flexible but strong -material, such as plastic or reinforced textile material, etc- The eyes 366 are shown as solid Lines in a position facing to the side of the rails, and as dotted Lines in another position intended to show the shape of the eyes- The eyes exhibit a part which encloses the rail 303 and which is capable of being moved along it so as to permit the 'spike, etc., to be driven into the ground at a suitable point, depending on the nature of the base.

When erecting the frame from its collapsed position shown in Fig. 22 (the tent canvas is not shown in the interests of clarity), the side pieces 310 of the rails 303 .are first swung outwards about the connecting Links 309 , whereupon the rails are swung outwards from each other about the pivot, pins 315, 316 in the hinged joint 303 . This involves straightening out the stays 305 , which means that the tracks 317, 318 must be swung about the pivot pin 316 until they reach a certain angular position which is maintained when the frame is in its erected state and standing on a base- For the purpose of imparting additional stability to the hinged joint 303 , the pivot pins 315 are

engaged in the grooves 364 in the supporting element 361 . The frame is collapsed in the reverse order, when partial collapse of the frame leaving only one or two rails erected will produce an opening in the tent.

Bending may take place either through 90 or through 180 , depending on the particular circumstances. Bending may, of course, take place to angles in excess of those stated above.

In the modified embodiment of the frame for a hangar tent illustrated in Fig. 23, the component parts which correspond to those shown in Fig. 12 have been given the same reference designations, but have been placed in a numerical series commencing at 400. In the embodiment in accordance with Fig. 23, a stronger construction has been preferred with lattice structures in both the stays 405 and the top pieces 411, 416 . The stays 406 on the gable pieces are, ^* for example, executed instead from a number of tubes welded together, which run parallel to each other and which appear to offer particularly high strength characteristics- This frame, too, is collapsible in two directions, with one half collapsing to one side and the other half collapsing to the other side, when the superjacent cross—stays 412, 413 are intended to be removed when the hangar is opened. In spite of the fact that this may not be apparent from the Figures, the hangar can be opened to a half-open position by detaching the stays 405 which extend from the tubes lying on the ground at their upper ends and by swinging them down about a pivot pin 415 situated on the appropriate base plate 414 , when the top pieces .416 may be lowered onto the tubes lying on the ground. This will produce a large opening which is intended to be used, under certain circumstances when a certain degree of protection is needed against winds or other climatic effects, at the same time as the maximum amount of light is required, for example- In the position illustrated in fig- 23, but with the tent canvas in place, the tent will be given essentially the same appearance as the embodiment in accordance with Fig- 11. In other respects the frame exhibits a raising arrangement 417 located on the central connecting Link 403 , said raising arrangement consisting of an

upright 418 through which run two lines 419, 420 . These pulling lines run inside the upright 418 which is executed in the form of a hollow pole, from the upper end of which the two lines extend, each in its own direction, and are attached by their outer ends to the most upright of the frame rails 402 . At the upper end of the upright 418. are most appropriately arranged two link pulleys on a common shaft. Towards the bottom of the upright 417 the lines 419, 420 are wound onto a winch 421 which consists of the drum illustrated here and an electric motor. The raising arrangement 417 also serves as a Lowering arrangement and is designed to be detachable so that it may be removed when the tent has been collapsed. For this purpose the upright 418 with the winch 421 mounted on it is capable of being removed from the articulated arrangement 403 , into which it is inserted. The Lines 419, 420 are also capable of being unhooked at their outer ends from the frame rails. Raising from a fully or partially collapsed state proceeds in such a way that the Lines are attached to the frame rails or, as may be appreciated from the example illustrated, to a stepped structure, when the hollow pole is lowered between the plates in the articulated arrangement 403 , where suitable guides are arranged to hold the upright in position. Before the Lines are attached, a check is, of course, made to ensure that a sufficient length of Line has been unrolled. A raising arrangement is provided at each gable of the hangar tent. The raising arrangement is then actuated by starting up the winch after having connected it to a source of electrical voltage in the helicopter or on some other vehicle, when the two closest frame rails will be Lifted- upwards towards each other- As will be appreciated, the constituent elements of the frame will balance out each other so that the load imposed on the upright from the two directions will be evenly distributed to all intents and purposes- The covering material in the form of a tent canvas may remain securely attached to the appropriate constituent elements of the frame or may be so arranged that the canvas is installed subsequently, once the frame has been raised. In this case, the canvas is divided up into a number of sections.

The two openings which permit the rotors of the helicopter 60 to be situated outside the tent are tailored in such a way that a close fit is provided around the component parts of the helicopter, which can be achieved by the use of sleeve or similar arrangement extending around the edge of each opening.

The invention is not restricted to the typical embodiment specified above and illustrated in the accompanying drawings, but may be modified within the context of the following Patent Claims. It is evident from the drawings that the expression frame rail does not necessarily denote a bow—shaped unit, but denotes any bridging element which is.capable of supporting a tent canvas. The articulated arrangement in accordance with the invention may be used for different applications in which it is of advantage to be able to achieve the rapid and reliable collapse of the structure by folding the constituent elements of the frame between an operating position and a collapsed position.

The hinged joint 303 can, as indicated above, retain its function when used without the supporting element 361 , for example in small tents. The frame may be of a different type in which the central hinged joint is not included, and in which the frame rails are capable of being moved in parallel to each other between an erected position and a position in which they are moved apart in order to form a collapsible protective enclosed space. This frame may thus exhibit stays between the frame rails, whereby both the stays and the frame rails are capable of being folded about articulated arrangements in accordance with the invention. Each individual frame rail may also be provided with a securely attached length of U—shaped profile to which, the stays are flexibly attached and are so arranged as to be introduced into the U-shaped profile during folding in order to protect the canvas material- The frame can also be raised by lifting from the ground those frame rails which are Lying on the ground together with the central hinged joint by the use of supplementary supporting legs, which may be detachable.

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