Abstract:
The invention relates to a method of folding an item comprising a structure of arcs that can be folded between an open position for use and a folded position for storage, in which the item has a circular configuration. It is particularly applicable to folding tents, shelters and ball game devices. The invention thus relates, in a first aspect, to a method of folding an item comprising a structure of arcs that can be folded with at least one closed loop, in a folded position in which this loop takes the form of three preferably circular superposed turns. The method consists particularly in forming with the loop an essentially planar figure comprising three loops: a central loop and two side loops, all essentially in the same plane. Each side loop is then folded down onto the central loop to form the three superposed turns.

Description:
[0001]    This is a 371 national phase application of PCT/FR2009/050479 filed 20 Mar. 2009, claiming priority to French Patent Application No. 08/51851 filed 21 Mar. 2008, the contents of which are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention concerns the field of items that include a structure of one or several arcs, and that can be folded between an open position for use and a folded position for storage, in which they have a substantially circular configuration. This invention is particularly applicable to folding item such as tents, shelters, or ball game devices. 
       BACKGROUND OF THE INVENTION 
       [0003]    These items generally comprise an upper skin, often called roof skin in the case of a tent or shelter. Arc structures occur when this skin is connected with flexible structural elements that assume, in the open position of the item, a circular arc configuration. These structuring elements can be made up of flexible rods with elastic recoil, in particular formed by rods made of a composite or metal or plastic material, the rods possibly being connected to each other. 
         [0004]    In some items, the flexible rods are straight in the folded position for storing the item and only assume the circular arc configuration when the item is assembled. This is particularly the case for certain tents generally referred to as dome tents. 
         [0005]    In other items, the structuring elements form a closed loop, this loop making it possible in particular to make the item three-dimensional. Such an item is described in document U.S. Pat. No. 3,960,161, for example. In that document, the structuring element, in closed loop form, assumes, in the folded position of the item, the form of three superimposed turns or coils. The same is true for the tent described in document U.S. Pat. No. 3,675,667. 
         [0006]    Other examples of such items are known from the following documents: U.S. Pat. No. 5,816,278, U.S. Pat. No. 6,357,510, U.S. Pat. No. 5,411,046, U.S. Pat. No. 5,249,592, FR 2,805,300, U.S. Pat. No. 5,137,044, U.S. Pat. No. 5,592,961, U.S. Pat. No. 7,246,630, or U.S. Pat. No. 5,427,381. 
         [0007]    To fold up such items, the stresses exerted by the flexible rods making up the arc structure tend to prevent the formation of the three superimposed coils. This is even more true when the diameter of the coils is smaller. 
         [0008]    Yet to reduce the bulk of the item in the folded position, it is necessary to manage to reduce the diameter of those coils, and therefore increase the number of coils with a constant initial diameter of the structure. 
         [0009]    Having three coils therefore corresponds to a satisfactory solution particularly in terms of the final bulk and folding difficulty. 
         [0010]    Items such as those described in the aforementioned documents must therefore be able to be easily and quickly folded by the user, in order to obtain an item in the folded position that has a small bulk and is easy to transport. 
         [0011]    In each of those documents, folding the item consists primarily, from the assembled, therefore three-dimensional, shape, of interlinking the loops making up the item to be folded with each other. If the assembled item does not assume a configuration in which the loops designed to form the final coil are already formed, the loops may be interlinked at the same time they are assembled. 
         [0012]    In particular, in U.S. Pat. No. 5,592,961, with the loop of the arc structure, a substantially flat structure with three smaller loops, substantially aligned (i.e., whereof the three respective centers are substantially aligned) is formed, then antagonistic forces are superimposed on the three smaller loops at both ends of the three-loop flat figure previously formed, thereby causing the two ends of that flat figure to pivot toward each other. 
         [0013]    In each of the known documents, the described method therefore consists of a succession of laborious steps during and at the end of which the object to be folded is kept in a three dimensional configuration, with the exception, of course, of the final configuration with three superimposed coils that one can liken to a substantially flat configuration, and possibly an intermediate configuration forming a substantially flat three-loop figure. 
         [0014]    The problem posed by these folding methods is therefore the difficulty of implementing them. These methods are particularly difficult for a single person to implement. Indeed, simultaneously manipulating three loops in three dimensions is difficult. 
         [0015]    The problem that then arises is that of having a method for folding an item that includes an arc structure, from an open position to a folded position in which the arc structure forms a series of three superimposed coils, that is fast and easy to implement, in particular by a single person. 
       SUMMARY OF THE INVENTION 
       [0016]    The aim of the invention is therefore to provide a solution to the aforementioned problem, among others. 
         [0017]    The invention thus concerns, according to a first aspect, a method for folding an item that includes an arc structure capable of being folded on itself comprising at least one closed loop, in a folded position in which said loop assumes the form of three superimposed coils. These coils are preferably substantially circular, but can also be oblong or oval. 
         [0018]    The method consists in particular of forming, with the loop, a first substantially flat figure with three loops: a central loop and two side loops, all substantially in the same plane. 
         [0019]    Characteristically, each of these side loops is then successively folded down onto the central loop to form the three superimposed coils. 
         [0020]    Specifically, a first of the two side loops is first folded down on the central loop, then the second of these two side loops is folded down on the central loop and the first side loop, to form these three superimposed coils. 
         [0021]    In other words, one first forms a second substantially flat figure from the first substantially flat figure, by folding a first of the two side loops down on the central loop, then one forms the three superimposed coils by folding the second of the two side loops down on the second substantially flat figure. 
         [0022]    Thus, the folding method is easy to carry out, in particular by a single person, due to the step at the end of which the initial loop forms a flat figure with three smaller loops. 
         [0023]    It is thus not necessary to manipulate the three loops intended to form the three final coils all at the same time. 
         [0024]    Keeping the loop in a substantially flat shape at the end of each step (creation of the first substantially flat figure with three loops in the same plane, creation of the second substantially flat figure by superimposing a first side loop on the central loop, and superimposing the second side loop on the assembly formed by the superposition of the first side loop on the central loop, i.e., on the second substantially flat figure), facilitates the implementation of the folding, for example, by keeping the assembly on the ground. 
         [0025]    In a first alternative, to form the first flat three-loop figure, one grasps a first portion of the loop having an apex and brings it into the plane of the complementary potion of said loop also having an apex, such that on one hand the first portion crosses the complementary portion at two intersection points, and on the other hand, the apex of the first portion is past the apex of the complementary portion. 
         [0026]    Thus, in a single and simple suitable manipulation, the initial loop is subdivided into three smaller loops in a same plane and ready to be superimposed to form the three final coils. 
         [0027]    Alternatively, to form the first flat figure, one grasps a first portion of the loop and twists it so as to create a first point of intersection. One then grasps a second portion of the loop, opposite the first portion, and also twists it so as to create a second point of intersection. 
         [0028]    In both of these alternatives, to fold the first side loop down on the central loop (i.e., to form the second substantially flat figure), or the second side loop on the central loop and the first side loop forming the second substantially flat figure (i.e., to form the three superimposed coils), one pivots said first or second side loop around its point of intersection with said central loop. 
         [0029]    In another alternative, possibly in combination with the two preceding alternatives, the arc structure comprises several loops with substantially the same dimensions. In this case, before forming the first flat figure, these loops are superimposed so as to form virtually a single closed loop, to which the method as described above can then be applied. 
         [0030]    Preferably, in this case, the superimposed loops are kept together using at least one fastening element, for example a diametral strap or an attachment, to facilitate later handling of this loop superposition as a single loop. 
         [0031]    In still another alternative, possibly in combination with any one or several of the preceding alternatives, the three superimposed coils are kept together using a fastening element preferably of the diametral strap type, or of the attachment type. 
         [0032]    In still another alternative, possibly in combination with any one or several of the preceding alternatives, the three superimposed coils are inserted into a cover, preferably circular, but which can also be oblong or oval. 
         [0033]    The invention also concerns, according to a second aspect, an item including an arc structure itself comprising at least one closed loop, folded into a folding position in which the loop assumes the form of three superimposed coils, preferably substantially circular, obtained using the folding method as presented above. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0034]    Other features and advantages of the invention will appear more clearly and completely upon reading the following description of preferred embodiments of the method, which are provided as non-limiting examples and in reference to the following appended drawings: 
           [0035]      FIG. 1  is a diagrammatic perspective illustration of the arc structure of a tent-type item, in the open position, 
           [0036]      FIG. 2  is a diagrammatic and side illustration of a tent-type item, in the open position; 
           [0037]      FIGS. 3 to 6  are diagrammatic illustrations of the different steps of the method according to the invention, in a first embodiment, 
           [0038]      FIGS. 7   a  to  7   c  are diagrammatic illustrations of the transition from the  FIG. 3  stage to the  FIG. 4  stage (formation of the first flat figure in the first embodiment), 
           [0039]      FIGS. 8 to 12  are diagrammatic illustrations of the different steps of the method according to the invention in a second alternative embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0040]      FIG. 1  shows an arc structure of a tent-type item  1  in the open position. 
         [0041]    In this example, the structure comprises two closed loops  2 ,  2 ′. Precisely, the structure has an upper loop  2  and a lower loop  2 ′. 
         [0042]    To explain the folding method, which is discussed a bit later in this description, different points of the upper  2  and lower  2 ′ loops are also referenced in  FIG. 1 . 
         [0043]    Thus, referenced in  FIG. 1  are two opposite ends or apices  3   a  and  4   a  of the upper loop  2 , corresponding to the two lower ends of said upper loop  2 , or the two ends in which said upper loop  2  meets the lower loop  2 ′ in the open position. These ends or apices  3   a  and  4   a  are therefore combined with two opposite ends or apices of the lower loop  2 ′. 
         [0044]    Also referenced in  FIG. 1  are the two ends or apices  10  and  11  of the upper loop  2 , at the uppermost points of said upper loop  2  in the open position, or at the points of said upper loop  2  that are furthest from the lower loop  2 ′ in the open position. 
         [0045]    Lastly, illustrated in  FIG. 1  are two other opposite ends or apices  12  and  13  of the lower loop  2 ′, at the points of said lower loop  2 ′ farthest from the upper loop  2  in the open position. 
         [0046]      FIG. 2  is a diagrammatic illustration of the tent  1  provided with the arc structure illustrated in  FIG. 1 , with a skin  7 , generally called roof skin, stretched between the arcs of the structure. 
         [0047]    Traditionally, the loops  2  and  2 ′ are slid into sheaths connected, for example by sewing, to the roof skin  7 . 
         [0048]      FIGS. 3 to 6  show the main steps of the folding method according to the invention, in a first embodiment, applied to a general folding item that comprises at least one closed loop  2 . 
         [0049]    The application of this method to the specific case of an item  1  with two closed loops  2 ,  2 ′, as illustrated in  FIGS. 1 and 2 , will be discussed later. 
         [0050]      FIG. 3  therefore illustrates the closed loop  2 , as illustrated in  FIG. 1 , seen from below. Depending on the item in question, like for instance with the tent  1  illustrated in  FIG. 2 , this loop  2  is not necessarily flat, as we will see in particular in reference to  FIGS. 7   a  and  7   b . But the selected bottom view shows the projection of said loop  2  in a plane, therefore in the form of a flat curve that can be oblong or circular, for example. 
         [0051]    According to the method of the invention, to fold the item provided with the arc structure comprising such a loop  2 , one forms, from said loop  2 , a first substantially flat figure, comprising a central loop  2   b,  and two side loops  2   a  and  2   c , as shown in  FIG. 4 , in one example. 
         [0052]    In this example, to form this first flat figure, one grasps the first portion  3  of the loop  2  comprising the apex  3   a,  and gradually folds it down in the plane of the complementary portion  4  of the loop  2  comprised by the apex  4   a.  To do this, one exerts pressure along an axis perpendicular to the axis connecting the apices  3   a  and  4   a  to tighten the first portion  3  for the subsequent formation of the central loop  2   b.    
         [0053]    At the end of that operation, the first portion  3  crosses the complementary portion  4  at two intersection points  5  and  6 , and the apex  3   a  of the first portion  3  is past the apex  4   a  of the complementary portion  4 . 
         [0054]    The operation to go from the stage of  FIG. 3  to that of  FIG. 4  as described in the preceding paragraph is broken down in  FIGS. 7   a  to  7   c , in a succession of perspective views of the loop  2 . 
         [0055]      FIG. 7   a  therefore corresponds to a perspective view of the loop  2  as illustrated in  FIG. 3 , and  FIG. 7   c  therefore corresponds to a perspective view of the loop  2  as illustrated in  FIG. 4 . Moreover,  FIG. 7   b  corresponds to a perspective view of the loop  2  in an intermediate position, when the first portion  3  of the loop  2  has not yet been completely folded down in the plane of the complementary portion  4 . 
         [0056]    When the first flat figure is thus formed, one folds one of the side loops  2   a  down on the central loop  2   b,  to form the substantially flat intermediate figure, or second substantially flat figure, as illustrated in  FIG. 5 . 
         [0057]    To fold this side loop  2   a  down on the central loop  2   b,  the side loop  2   a  is pivoted around its point of intersection  5  with the central loop  2   b.    
         [0058]    Lastly, the other side loop  2   c  is folded down on the central loop  2   b  and the first side loop  2   a,  therefore on the second substantially flat figure, in the same way. 
         [0059]    Specifically, to fold this side loop  2   c  down on the central loop  2   b  and the side loop  2   a,  one pivots said side loop  2   b  around its point of intersection  6  with the central loop  2   b.    
         [0060]    At the end of these operations, the loop  2  assumes the form of three superimposed coils  2   a,    2   b  and  2   c,  as illustrated in  FIG. 6 . 
         [0061]    These coils are preferably substantially circular, but can also be oblong or oval. 
         [0062]    It may then be possible to insert these three superimposed coils  2   a  to  2   c  into a cover, preferably substantially circular, provided to that end. 
         [0063]    To facilitate this insertion into the cover, and avoid untimely reopening of the loop  2 , it is possible to provide a fastening element making it possible to keep these three coils  2   a  to  2   c  together. This may, for example, be a diametral strap, preferably elastic, or one or several attachments. 
         [0064]    The application of the method as presented above to the tent  1  illustrated in  FIGS. 1 and 2  requires that the two lower  2 ′ and upper 2 loops be joined together, or superimposed, so as to form virtually one single loop  2 , before forming the first flat figure then three superimposed coils. 
         [0065]    In this example, the superposition of the two loops  2  and  2 ′ is obtained by making the apices or ends  12  and  13  of the lower loop  2 ′ farthest from the upper loop  2  in the open position, coincide with the ends or apices  10  and  11  of the upper loop  2  farthest from the lower loop  2 ′ in the open position, respectively. 
         [0066]    The user then holds the lower loop  2 ′ and the upper loop  2  in one hand at the respective apices  13  and  11 , and the lower loop  2 ′ and the upper loop  2  at the respective apices  12  and  10  in the other. 
         [0067]    The lower  2 ′ and upper 2 loops, thus joined together or superimposed, then virtually form a single loop  2  as illustrated in  FIG. 3  or  7   a.    
         [0068]    To facilitate handling of this virtual loop  2  actually comprising the two joined together or superimposed lower  2 ′ and upper 2 loops, one may provide for keeping these two loops  2 ,  2 ′ together using at least one fastening element (one or several attachments, for example). 
         [0069]    The user must also coil this virtual loop  2  over, such that its convexity is oriented upward as in  FIG. 7   a , and not downward as in  FIG. 1 , to implement the folding method detailed above in reference to  FIGS. 3 to 6  and  7   a  to  7   c.    
         [0070]    In another alternative, the formation of the first flat figure with three loops  2   a ,  2   b,    2   c  can be obtained in another way, as illustrated in  FIGS. 8 to 12 . 
         [0071]    In this alternative, one grasps a first portion  8  of the loop  2  as illustrated in  FIG. 8 , and twists it so as to create a first point of intersection  5 , as illustrated in  FIG. 9 . 
         [0072]    One then grasps a second portion  9  of the loop  2 , opposite the first portion  8 , and twists it in coil so as to create a second point of intersection  6 , as illustrated in  FIG. 10 . 
         [0073]    In this  FIG. 10 , the first flat figure with three loops, one central  2   b  and the other two side  2   a  and  2   c,  therefore comprises three loops  2   a  to  2   c  that are substantially aligned (in that their respective centers are substantially aligned), whereas in the first alternative ( FIG. 4 ), the two side loops  2   a  and  2   c  are offset in relation to the central loop  2   b  so as to form a sort of clover (in that their respective centers form the apices of a substantially isosceles, possibly equilateral triangle). 
         [0074]    Then, in the same way as in the previous alternative, the side loops  2   a  and  2   c  are successively folded down on the central loop  2   b,  to form the three superimposed coils  2   a,    2   b,    2   c  of  FIG. 12 . 
         [0075]    As a result, to fold the side loop  2   a  down on the central loop  2   b  and thereby form a second substantially flat figure, one follows the same procedure as in the first alternative: the side loop  2   a  is pivoted around its point of intersection 5 with the central loop  2   b.    
         [0076]    Likewise, to fold this side loop  2   c  down on the central loop  2   b  and the side loop  2   a  forming the second substantially flat figure, this side loop  2   b  is pivoted around its point of intersection  6  with the central loop  2   b.    
         [0077]    Of course, in this alternative as well, at the end of these operations, the loop  2  assumes the form of three superimposed coils  2   a,    2   b  and  2   c  that are preferably substantially circular, or possibly oblong or oval. 
         [0078]    In this case as well, these three superimposed coils  2   a  to  2   c  can be inserted into a sheath, preferably substantially circular, provided to that end. 
         [0079]    In the same way to facilitate this insertion into the sheath, and prevent untimely reopening of the loop  2 , a fastening element can be provided making it possible to keep these three coils  2   a  to  2   c  together, such as a diametral strap, preferably elastic, or one or several attachments. 
         [0080]    This description is provided as an example and therefore does not limit the invention. 
         [0081]    In particular, the invention is not limited to folding a tent as illustrated in  FIGS. 1 and 2 , but applies to a tent whereof the arc structure has a single loop  2  or more than two loops  2 ,  2 ′. 
         [0082]    Moreover, as indicated in the introduction, the method according to the invention is not limited to folding a tent, but concerns the folding of any item with an arc structure comprising at least one closed loop, such that this loop assumes, in folded position, the form of a superposition of three coils. As a result, the method also applies to other examples of such items, such as foldable shelters or ball game devices. 
         [0083]    Lastly, the invention is not limited to the two embodiments presented above to form the first flat figure with three loops. Other ways of forming such a figure can be considered, provided that they go through the step of forming a first flat figure with three loops, i.e. three loops substantially in the same plane, that one can then easily fold down on each other as described above.