Abstract:
A hub leg joint system is provided in which twisting of poles for a shelter is prevented. The hub leg joint system includes a hub having a socket or opening for receiving an end of a pole for a shelter. The opening and the end are configured so that the end may be inserted into the opening, but may not be rotated therein. As an example, the opening and the ends may have a cross section that is oblong in shape.

Description:
TECHNICAL FIELD OF THE INVENTION  
       [0001]     The present invention is directed to shelters, and more specifically to a shelter having a pole frame.  
       BACKGROUND OF THE INVENTION  
       [0002]     Camping is a popular recreational activity enjoyed by many. Some people camp so that they may enjoy the outdoors, and others use camping as an inexpensive alternative to staying in a hotel.  
         [0003]     One structure that is often used while camping is a shelter. In general, a shelter is a structure, typically framed with poles, that includes a covering or canopy that provides protection from the rain and/or sun. For camping, a shelter is typically made of fabric and foldable poles so that the shelter may be folded into a compact configuration for transport and storage. The shelter may or may not have walls, such as screen walls. The shelter may be, for example, set up over a picnic area, used adjacent to a tent as a storage area, serve as protection from the rain, or may be used as a screened area to avoid insects.  
         [0004]     Although shelters work well for their intended purpose, in practice, the shelters may not be stable enough to handle higher winds. Some prior art shelters have addressed this problem by providing additional poles in the frame, such as poles that extend horizontally between the support poles for the shelter. Such additional poles add to the weight and size of the stored shelter, and add installation complexity and time. However, a shelter that has a minimal number of poles is subject to stability problems, mainly because the connection of the poles has been known to twist, resulting in a collapse of the shelter.  
       SUMMARY OF THE INVENTION  
       [0005]     The following presents a simplified summary of some embodiments of the invention in order to provide a basic understanding of the invention. This summary is not an extensive overview of the invention. It is not intended to identify key/critical elements of the invention or to delineate the scope of the invention. Its sole purpose is to present some embodiments of the invention in a simplified form as a prelude to the more detailed description that is presented later.  
         [0006]     In accordance with an embodiment of the invention, a hub leg joint system is provided in which twisting of poles for a shelter is prevented. The hub leg joint system includes a hub having a socket or opening for receiving an end of a support pole for a shelter. The opening and the end are configured so that the end may be inserted into the opening, but may not be rotated therein. As an example, the opening and the ends may have a cross section that is oblong in shape.  
         [0007]     The connection of the pole to the hub prevents rotation of the pole relative to the hub. Such a connection may be provided for each of the pole attachments to the hub. Thus, stability is provided for the shelter.  
         [0008]     Other features of the invention will become apparent from the following detailed description when taken in conjunction with the drawings, in which:  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]      FIG. 1  is a side perspective view of a shelter incorporating an embodiment of the invention, with a fabric canopy for the shelter shown in phantom;  
         [0010]      FIG. 2  is an exploded side perspective view of a hub leg joint system in accordance with an embodiment of the invention;  
         [0011]      FIG. 3  is a sectional view taken along the section lines  3 - 3  of  FIG. 2 ; and  
         [0012]      FIG. 4  is a side perspective view of a second shelter incorporating a second embodiment of the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0013]     In the following description, various embodiments of the present invention will be described. For purposes of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the embodiments. However, it will also be apparent to one skilled in the art that the present invention may be practiced without the specific details. Furthermore, well-known features may be omitted or simplified in order not to obscure the embodiment being described.  
         [0014]     Referring now to the drawings, in which like reference numerals represent like parts throughout the several views,  FIG. 1  shows a shelter  20  incorporating an embodiment of the invention. The shelter  20  includes a pole assembly  22  over which is extended a fabric canopy  24 . The fabric canopy  24  is shown in phantom in the drawings so as not to obscure the pole assembly  22 . The fabric canopy  24  may be made of a variety of different materials, including rip stop nylon, canvas, polyethylene, or other suitable materials. In addition, while the embodiment shown in the drawings does not include walls, walls may be provided on one or some of the sides of the shelter  20 . The walls may be made of the same fabric material as the fabric canopy  24 , or may be made of a different material, such as screen. Walls for shelters are well known in the art, and a person of ordinary skill may select a suitable fabric and design for a desired configuration and use of the shelter  20 .  
         [0015]     The pole assembly  22  shown in  FIG. 1  includes four upright poles  26 ,  28 ,  30 , and  32 . The upright poles  26 - 32  may be formed of segments of metallic poles, such as steel, aluminum, or another suitable material. Such poles  26 - 32  may be attached end-to-end to form a complete upright pole in a manner known in the art. The four poles  26 - 32  for the pole assembly  22  are identical in shape, and therefore are interchangeable. However, embodiments of the invention could utilize different sizes and shapes of upright poles. However, the structure shown provides an embodiment with the upright poles  26 - 32  being interchangeable, thus requiring less thought in preparation for assembly.  
         [0016]     Each of the upright poles  26 - 32  includes a bend  33  approximately half way along its length. In this manner, each of the upright poles  26 - 32 , when installed, has a lower portion  34  that extends substantially vertically, and an upper portion  35  that extends at an angle to vertical, in the embodiment shown at approximately 60 degrees to vertical. The lower portion  34  is separated from the upper portion  35  at the bend  33 .  
         [0017]     Curved upright poles such as are shown in  FIG. 1  are known in the art, and provide the benefit of expanding shelter space without making a shelter taller. That is, if the poles did not include a bend such as the bend  33 , to have the same amount of area covered by the shelter, the shelter must be taller.  
         [0018]     Although each of the upright poles  26 ,  28 ,  30 , and  32  is shown as a continuous pole that extends from the top portion of the shelter  20  to the ground, as described above, the poles could be made from a plurality of pole sections. These pole sections may be connected by an internal shock cord in a manner known in the art. In addition, one or more intermediate structures may be provided between different sections of an upright pole, for example between the upper and lower portions  34 ,  35 .  
         [0019]     The rear two upright poles  26 ,  28  extend to a rear hub  36 , and the front two upright poles  30 ,  32  extend to a front hub  37 . The hubs  36 ,  37  preferably are made of plastic or another suitable material. In the embodiment shown, the hubs  36 ,  37  are identical in construction, and are therefore interchangeable, providing ease shelter construction and manufacture. However, the hubs  36 ,  37  may be configured in a different way by a person of skill in the art so as to provide a shelter of a desired configuration and size.  
         [0020]     A ridge pole  38  extends between the two hubs  36 ,  37 . The ridge pole  38  provides two functions. First, the ridge pole  38  supports an upper portion of the fabric canopy  24 . Second, the ridge pole separates the two hubs  36 ,  37  so that the shelter  20  may cover more ground without having to raise the height of the shelter  20  or decrease the angle of the fabric canopy  24 , which could result in undesirable pooling of water at the edges of the fabric canopy  24 .  
         [0021]     Detail of the hub  36  is shown in  FIG. 2 . As stated above, this hub  36  is identical to the hub  37 . Thus, for ease of description, the structure of only one of the hubs, hub  36 , is described here.  
         [0022]     The hub  36  is triangularly shaped, with openings  40 ,  42 ,  44  at each of the corners. The openings  40 - 44  are elongate holes that extend toward the center of the hub  36 . The opening  44  includes a round cross section, while the openings  40 ,  42  are oblong, and have a cross section having flat sides  43  ( FIG. 3 ) and rounded tops and bottoms  45 .  
         [0023]     Each of the openings  40 - 44  includes a slot  46  extending through the top of the hub  36  and into the opening. The openings  40 ,  42  are configured to receive ends  48 ,  50  of the upright poles  26 ,  28 . These ends  48 ,  50  are slightly narrower in cross section than the remainder of the poles  26 ,  28 , are oblong in shape, and include flat sides  49  and rounded tops and bottoms  51 , as can be seen in  FIGS. 2 and 3 . The ends  48 ,  50  are preferably sized so that the flat sides  49  and rounded tops and bottoms  51  fit tightly against the inside of the flat sides  43  ( FIG. 3 ) and rounded tops and bottoms  45  of the openings  40 ,  42 .  
         [0024]     A clip  52 ,  54  is arranged inside each of the ends  48 ,  50  of the uprights poles  26 ,  28 . A portion of each clip  52 ,  54  extends out of a slot  55  from the top portion of the respective upright pole  26  or  28 . As is known in the art, the clip  52 ,  54  is designed to press inward as the respective end  48 ,  50  of the poles  26 ,  28  is extended into the opening  40  or  42 . The clip  52 ,  54  then pops upward and out of the respective slot  46  for the opening  40  or  42 . A similar clip (not shown) may be provided at the ends of the ridge pole  38 .  
         [0025]     The flat sides  49  and rounded tops and bottoms  51  of the ends  48 ,  50  fit tightly against the inside of the flat sides  43  and rounded tops and bottoms  45  of the openings  40 ,  42 , preventing rotation of the upper portion  35  of the upright poles  26 ,  28  within the hub  36 . This feature provides advanced stability for the shelter  20 , because prevention of rotation of the upper portion  35  of the upright poles  26 ,  28  prevents the lower portion  34  from moving in the directions of the arrows K and M shown in  FIG. 1 . Reducing this twisting effect increases the stability of the shelter  20 , making the shelter more stable in strong wind conditions.  
         [0026]     Although the configuration of the ends  48 ,  50  and the openings  40 ,  42  works well to prevent twisting, other configurations may be used. In general, any configuration that permits the upright poles  26 ,  28  to be attached to the hubs without the poles rotating relative to the hubs work perform this function. One example is the oblong shape fo the openings  40 ,  42  and ends  48 ,  50 . Another example includes at least one protrusion and a corresponding abutment surface in the respective opening. However, the particular configuration shown in the drawings is convenient in that the structure enjoys the benefit of the strength of tubular poles, yet has a configuration which prevents twisting.  
         [0027]     In the embodiment shown in  FIGS. 1-3 , the opening  44  for receiving the ridge pole  38  does not have an irregular cross section like the openings  40 ,  42 . This is because twisting at the ridge pole  38  does not affect the stability of the shelter  20 . However, if desired, the ridge pole opening  44  may also include an end and opening that are configured to prevent rotation of the ridge pole  38 .  
         [0028]     To aid in alignment and assembly of the upright poles  26 ,  28  to the hub  36 , indicia, such as the letters “A” and “B” shown in  FIG. 2  may be provided near the edge of the respective opening  40  or  42 , and the end  48  or  50  of the respective upright poles  26 ,  28 . In this manner, a user may quickly assemble the upright poles  26 ,  28  with the lower portion  34  of the upright poles  26 ,  28  being directed in the proper, downward position, without a user attempting to attach either of the upright poles  26 ,  28  to the opening  44 .  
         [0029]     Although each of the upright poles  26 ,  28 ,  30 , and  32  is shown as a continuous pole that extends from the top portion of the shelter  20  to the ground, as described above, the poles could be made from a plurality of pole sections. These pole sections may be connected by an internal shock cord in a manner known in the art. In addition, one or more intermediate structures may be provided between different sections of an upright pole, for example between the upper and lower portions  35 ,  34 . However, to avoid rotation of the lower portion  34  of an upright poles  26 - 32 , there should be no rotation between the attachment of the respective upright pole to the hub  36  and a position on the pole just below the bend  33  for the upright pole. Thus, if segments are provided between this location and the hub  36 , these segments should be configured so that, when installed, they do not rotate relative to one another.  
         [0030]     Another embodiment of a shelter  56  is shown in  FIG. 4 . The shelter  56  includes a pole assembly  58  having four upright poles  60 ,  62 ,  64 ,  66  covered at a top portion by a fabric canopy  68 . This shelter  56  is similar to the shelter  20 , but does not include a ridge pole  38  and has only one hub  70 . In addition, the hub  70  has four spokes for attachment of the four upright poles  60 - 66 .  
         [0031]     Because each of the openings in the hub  70  attach to an upright pole  60 - 66 , preferably each of the each of the upright poles will attach to respective openings for the hub  70  without permitting rotation. For example, each opening may including an oblong cross section similar to the one shown for the openings  40  and  42  in  FIGS. 2 and 3 . As such, each connection of the upright poles  60 - 66  to the hub  70  is formed so that the respective upright pole  60 - 66  does not rotate relative to the hub  70 .  
         [0032]     Other embodiments of shelters are also contemplated. For example, a five-sided shelter may include a five-spoke hub attached to five upright poles.  
         [0033]     The removable, non-rotating attachment of the upright poles to the hub is convenient in that it avoids rotation of the upright poles relative to the hub and adds stability to a shelter. The configuration disclosed in the drawings does so with little added cost and little to no reduction in strength of the upright poles.  
         [0034]     The upright poles disclosed in the drawings are advantageous in that they provide the sole support for the fabric canopy  24 . Thus, the shelter may be made lighter, and is easy to assembly and store. The fact that the upper portion  35  and the bend  33  cannot rotate provides a downwardly extending structural support for the lower portions of the upright poles that cannot rotate. As such, additional support for the downwardly extending structural support, such as poles or other structures, is not needed.  
         [0035]     If desired, different attachments may be made between the hubs and the upright poles. For example, the hubs may include a protrusion over which an end of an upright pole is seated. To this end, the hub may be any structure that is used to attach the upper portion  35  of two upright poles.  
         [0036]     In accordance with another embodiment of the invention, if desired, in order to avoid rotation of one of the upright poles (e.g., the upright poles  60 - 66 ) relative to a hub (e.g., the hub  70 ), that particular upright pole may be formed integrally with, or permanently connected to, the hub  70 . The other upright poles and ridge pole  38  (if applicable), however, are preferably removable, so that the pole assembly  22  or  58  may be disassembled into a compact configuration for storage.  
         [0037]     Other variations are within the spirit of the present invention. Thus, while the invention is susceptible to various modifications and alternative constructions, a certain illustrated embodiment thereof is shown in the drawings and has been described above in detail. It should be understood, however, that there is no intention to limit the invention to the specific form or forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention, as defined in the appended claims.  
         [0038]     The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The term “connected” is to be construed as partly or wholly contained within, attached to, or joined together, even if there is something intervening. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate embodiments of the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.  
         [0039]     Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.