Abstract:
A frame connector assembly is configured to releasably, rigidly, and safely join large frame members to one another to form temporary structures. A connector assembly typically comprises a housing, a hoop element, a first cam block, a second cam clock and a rotatable actuator adapted to be engaged by a torquing tool. The housing is secured within the first frame member. Rotation of the actuator causes the threadedly-engaged second cam element to force movement of the first cam element in a direction opposing a spring bias. The hoop element is resultingly pulled toward the housing, along with a cleat or other detent element which is affixed to the second frame member. The housing can be manufactured inexpensively by way of extrusion. The frame connector assembly is adaptable to facilitate rapid construction and disassembly of various frame joint configurations, including end-to-face joints, and mitered 90-degree joints.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates generally to portable display framing systems designed to form large temporary structures, particularly where such framing systems are substantially comprised of extruded metal frame members which are reversibly interconnected. 
       BACKGROUND 
       [0002]    The current art of fabricating large, portable display system frames typically involves two methods: nut-and-bolt assembly, and portable fabricating systems. Nut-and-bolt systems can be labor-intensive and inconvenient for use in constructing temporary, portable displays, as there are many separate parts which must be assembled and disassembled, and which may be easily lost. Portable fabricating systems on the other hand were developed specifically to construct portable and temporary frameworks. They commonly employ quick connection mechanisms that are quicker and easier to use and involve fewer parts than nut-and-bolt systems. However, conventional quick-connection mechanisms are typically designed to engage frame members having a channel, commonly called a “system groove,” that runs the length of one or more of its exterior faces. This system groove allows a “lock” connector located in the end of a perpendicular opposing member to grab the inside edge of the system groove with small hardened steel flanges. 
         [0003]    As the popularity of portable display structures has increased, so has the use of such products in larger framing applications. Applications requiring structure sizes from 20 feet wide by 20 feet long by 10 feet high to up to 100 feet in length and 30 feet in height are now more common. Snap frame systems typically have an inherent “looseness” at every joint, and are therefore not appropriate for use in applications requiring high strength. 
         [0004]    With conventional lock connector systems, the user typically inserts small flanges into small grooves and blindly engages the flanges. Because the user generally does not see the flanges of the lock connector engaging the respective groove, they cannot visually ensure that the flanges are seated properly. This is exacerbated when assembling large frames, as the girth, weight, and length of the members being attached to one another are so large that the user is even more likely to have difficulty aligning the small connector flanges into small grooves in the adjacent frame member. Such system groove products were designed to construct relatively small temporary frameworks, such as those used at indoor tradeshows and the like. 
         [0005]    Further, conventional system groove-engaging connection systems frequently place gravitational loads onto the lock flanges in a direction parallel to the system groove. Thus, any failure of the lock/groove interface, due to user error in engaging the lock or due to improper alignment, may result in the lock flanges (and the respective frame member) sliding down the associated groove or falling out of the groove entirely. 
         [0006]    What is needed is a quick-release frame connection system which is suited for the rapid assembly and disassembly of large, heavy display and event frameworks, is simpler to use than conventional quick connector systems, is more cost effective, and achieves these benefits while increasing overall safety. 
       SUMMARY 
       [0007]    Certain deficiencies of the prior art may be overcome by the provision of one or more embodiments of a frame connector assembly and related frame kits as discussed herein. 
         [0008]    A frame connector assembly may be received by a first frame member which is generally hollow and elongated along a first longitudinal axis. The frame connector assembly releasably secures the first frame member to a second frame member having, for example, a cleat element featuring a tongue portion. Embodiments of a frame connector assembly may comprise a connector housing, a hoop element, a first cam block, a second cam block and an actuator. 
         [0009]    The connector housing may have a connector axis and be adapted to be rigidly received substantially within the first frame member such that the connector axis is generally parallel with the first longitudinal axis. The hoop element may include a pair of legs and a cross member therebetween. The legs may extend through the connector housing for guided movement of the hoop element along the connector axis between a release position and a retention position. The connector housing, legs and cross member may collectively define a hoop eyelet adapted to receive the tongue portion therethrough. The hoop eyelet may be configured to generally loosely receive the tongue portion therethrough when the hoop element is in its release position. The hoop eyelet may be configured to loopingly draw the tongue portion toward the connector housing when the hoop element is moved toward its retention position. 
         [0010]    The first cam block may be affixed to the legs for axial movement therewith. The actuator may have an actuator axis and a threaded section along its shaft. The actuator may be at least partially received within the connector housing for rotation about the actuator axis. The second cam block is in threaded association with the actuator element for transport of the second cam block along the actuator axis between a first position and a second position upon rotation of the actuator element. A second camming face of the second cam block slidably engages a first camming face of the first cam block for forcing the first cam block toward its retention position upon transport of the second cam block toward its second position. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    Further advantages of the present invention may become apparent to those skilled in the art with the benefit of the following detailed description of the preferred embodiments and upon reference to the accompanying drawings in which: 
           [0012]      FIG. 1  is a diagrammatic perspective view of one example embodiment of a frame connector assembly in accordance with the present invention; 
           [0013]      FIG. 2  is a diagrammatic exploded view of the embodiment shown in  FIG. 1 ; 
           [0014]      FIG. 3  is a diagrammatic partial perspective view of one embodiment of a frame kit in accordance with the present invention, wherein a first frame member and a second frame member are about to be rigidly releasably secured to one another by way of the connector assembly of  FIG. 1 ; 
           [0015]      FIG. 4  is a diagrammatic partial perspective view of the embodiment similar to that of  FIG. 3 , but wherein the first and second frame members are rigidly releasably secured to one another by way of securing engagement between the connector assembly and a cleat element; 
           [0016]      FIG. 5  is a diagrammatic view of the frame kit shown in  FIG. 3 , wherein the frame members are shown in cross-section, the hoop element and first cam block are shown in their release position, and the second cam block is shown in its first position; 
           [0017]      FIG. 6  is a diagrammatic view of the frame kit shown in  FIG. 4 , wherein the frame members are shown in cross-section, the hoop element and first cam block are in their retention position, and the second cam block is shown in its second position; 
           [0018]      FIG. 7  is a diagrammatic partial cross-sectional view of a further embodiment of a frame kit in accordance with the present invention, wherein the first and second frame members have respective frame ends which are beveled and a portion of the connector housing extends outward of the first frame end for receipt by the second frame member by way of the second frame end; 
           [0019]      FIG. 8  is a diagrammatic partial cross-sectional view of the embodiment of  FIG. 7 , but wherein the frame members are rigidly connected to one another to form a frame joint at their respective beveled ends with a portion of the connector housing extending outward of the first frame end and received by the second frame member, thereby providing further torsional rigidity at the joint; 
           [0020]      FIG. 9  is a diagrammatic partial cross-sectional view of an embodiment similar to those of  FIGS. 6 and 8 , but wherein the frame joint is formed between a beveled first end of the first frame member and a lateral wall of the second frame member; 
           [0021]      FIG. 10  is a diagrammatic bottom view of the frame connector assembly of  FIG. 1 ; 
           [0022]      FIG. 11  is a diagrammatic rear view of the frame connector assembly of  FIG. 1 , showing the actuator element being confined within the outermost cross-sectional profile of the connector assembly as viewed along the connector axis; 
           [0023]      FIG. 12  is a diagrammatic front view of one embodiment of a cleat element in accordance with the present invention; 
           [0024]      FIG. 13  is a diagrammatic side view of the cleat element of  FIG. 12 ; 
           [0025]      FIG. 14  is a diagrammatic perspective front view of one embodiment of a cleat backer plate, which may preferably be configured to threadedly and reinforcingly receive bolts by which the cleat element is attached to the second frame member; and 
           [0026]      FIG. 15  is a diagrammatic top front view of one possible embodiment of a spring element in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0027]    Referring now to the drawings, like reference numerals designate identical or corresponding features throughout the several views. 
         [0028]    Referring to  FIGS. 1 ,  3  and  6 , for example, embodiments of a frame connector assembly  100  may be configured to be received by a first frame member  102 , which may be generally hollow and elongated along a first longitudinal axis  104 , for releasably securing the first frame member  102  to a second frame member  106  having a cleat element  110  with a tongue portion  114 . Typical preferred embodiments are designed to connect large frame members, each such frame member having an extruded cross section of approximately, for example, 120 mm by 120 mm. 
         [0029]    Referring to  FIGS. 1 and 2  for illustration, embodiments of a frame connector assembly  100  may typically comprise a connector housing  118 , a hoop element  122 , a first cam block  134 , an actuator element  142  and a second cam block  150 . The connector housing may have a connector axis  120  and be adapted to be rigidly received substantially within the first frame member  102  such that the connector axis  120  is generally parallel with the first longitudinal axis  104 . In embodiments, the connector housing  118  may preferably be a unitary metal component formed by extrusion in a direction substantially perpendicular to the connector axis  120 . The connector housing  118  of certain embodiments may be formed, for example, substantially of 6063 T5 Aluminum extrusion or the equivalent. 
         [0030]    A hoop element  122  may include, for example, a pair of legs  124  and a cross member  128  therebetween. The legs  124  may be at least partially received by the connector housing  118  for movement of the hoop element  122  generally along the connector axis  120  between a release position (as shown, for example, in  FIG. 5 ) and a retention position (as shown, for example, in  FIG. 6 ). In embodiments, the connector housing  118 , legs  124  and cross member  128  may collectively define a hoop eyelet  132  adapted for receipt of the tongue portion  114  of a cleat element  110  therethrough. Referring to  FIGS. 5 and 7 , for example, the hoop eyelet  132  may be configured to generally loosely receive the tongue portion  114  therethrough when the hoop element  122  is in its release position. Referring to  FIG. 6  for illustration, in particular preferred embodiments, the hoop eyelet  132  may be configured, for example, to loopingly draw the tongue portion  132  toward the connector housing  118  when the hoop element  122  is moved toward its retention position. The hoop element  122  of certain embodiments may be formed of ¼-inch steel rod, for example. 
         [0031]    In embodiments, a first cam block  134  may be affixed to the legs  124  for axial movement with the legs  124  generally along the connector axis  120 . 
         [0032]    Referring to  FIG. 1  for illustration, an actuator element  142  may have an actuator axis  144  and a threaded section  146  along a shaft. As shown in  FIGS. 5-9 , for example, the actuator element  142  may be at least partially received within the connector housing  118  for rotation of the actuator element  142  about the actuator axis  144 . The actuator element  142  may include a head portion  148  adapted to be torqueingly engaged by a hand-operated torqueing tool, by way of, for example, an access aperture  186  in the first frame member  102 . Such hand-operated torquing tool may preferably be a powered hand tool in order to expedite assembly and disassembly of the respective frame kit. As shown in  FIG. 1 , the actuator axis  144  may be substantially perpendicular to said connector axis. The actuator element  142  of certain embodiments may be, for example, a steel socket-head cap screw. 
         [0033]    In embodiments, a second cam block  150  may be, for example, in threaded association with the actuator element  142  for transport of the second cam block  150  along the actuator axis  144  between a first position (shown, for example, in  FIG. 5 ) and a second position (as shown, for example, in  FIG. 6 ) upon rotation of the actuator element  142 . A second camming face  152  of the second cam block  150  may be adapted to slidably engage a first camming face  136  of the first cam block  134  for forcing the first cam block  134  toward its retention position upon transport of the second cam block  150  toward its second position (see, for example,  FIG. 6 ). The second cam block  150  of certain embodiments may include a threaded brass insert which provides the means for direct threaded association with the actuator element  142 . 
         [0034]    Referring to  FIGS. 5 and 7  for example, in certain preferred embodiments of a frame connector assembly  100 , the first cam block  134  may be resiliently biased toward its release position. Referring to  FIGS. 6 and 8 , such resilient bias may be configured to be overcome by transport of the second cam block  150  from its first position toward its second position. In particular embodiments, the resilient bias may be provided by, for example, a spring element  174 . Referring to  FIGS. 2 and 15  for example, a flat spring  174  may have two laterally opposed cantilever spring arms  182 , and each arm may include a generally rounded end  184 . In embodiments, a flat spring  174  may be made substantially of formed spring steel. 
         [0035]    Referring to  FIGS. 1 and 2  for illustration, in particular embodiments, each leg  124  may have a threaded portion  126  at least partially received by the first cam block  134  and affixed thereto by way of a respective pair of threaded retainers  158  threadedly disposed on the threaded portion  126  on opposing sides of the first cam block  134 . Equivalent alternative means for affixing the hoop element  122  to the first cam block would be understood by persons skilled in the art, with the benefit of the teachings herein. 
         [0036]    Referring once again to  FIG. 1  for illustration, in certain preferred embodiments the connector housing  118  may include a first wall  162 , a second wall  164 , and an intermediate wall  166  therebetween. A cam compartment  168  may be generally defined between the first wall  162  and the intermediate wall  166 . A hoop alignment compartment  170  may be defined between the second wall  164  and the intermediate wall  166 . The first and second cam blocks may be housed substantially within the cam compartment  168 . The legs  124  may extend through the second wall  164  and intermediate wall  166 . The hoop eyelet  132  may extend generally outwardly of the second wall  164 . Embodiments of the connector housing  118  may further include one or more oblique walls  172  extending diagonally between the intermediate wall  166  and the second wall  164  to provide added strength to the assembly. 
         [0037]    In particular embodiments, the first cam block  134  may include a bias face  138  generally opposed to the first camming face  136 . In such embodiments, the resilient bias may be provided by a spring element  174  disposed between the first wall  162  and the bias face  138 . A spring lip  180  may be provided to prevent undesirable travel of the spring element  174  in a direction perpendicular to the connector axis. 
         [0038]    In certain embodiments, the second cam block  150  may include a second support face  154  generally opposed to the second camming face  152 . In such embodiments, the intermediate wall  166  may be configured to be supportingly associated with the second support face  154  for substantially preventing travel of the second cam block  150  toward the second wall  164  throughout transport of the second cam block  150  toward its second position. 
         [0039]    Referring to  FIG. 11  for illustration, in particular preferred embodiments, the connector housing  118  may have an outermost cross-sectional profile when viewed along the connector axis. Further, the actuator element  142  may preferably be substantially confined within the outermost cross-sectional profile. Such a configuration may make it more convenient for the fully-assembled connector assembly  100  to be axially inserted into the first frame member  102 . The connector assembly  100  may be rigidly received and retained within a first frame member by way of, for example, rivets, screws, bolts, high-strength glues, a combination thereof or the like. 
         [0040]    Given the operational loads and interactive movement applied between the first and second cam blocks, in preferred embodiments the first cam block and second cam block may be comprised substantially of a high-strength, low-friction polymer, such as, for example, a thermoplastic polyethylene. In particular preferred embodiments, the thermoplastic polyethylene may be ultra-high-density polyethylene. 
         [0041]    Referring now to  FIGS. 3-9  for illustration, embodiments of a frame kit  190  may comprise a first frame member  102 , a second frame member  106 , and a frame connector assembly  100 . The first frame member  102  may be generally hollow and elongated along a first longitudinal axis  104 . Similarly, a second frame member  106  may be elongated along a second longitudinal axis  108 . The second frame member  106  may have a cleat element  110  rigidly affixed thereto, by way of, for example, a set of bolts extending through the wall of the second frame member  106  and threadedly engaging a cleat backer plate  188 . A cleat element  110  of certain embodiments may be made substantially of ⅛-inch steel plate. The connector housing  118  may have a connector axis  120  and be adapted to being rigidly received substantially within the first frame member  102  such that the connector axis  120  is generally parallel with the first longitudinal axis  104   
         [0042]    Referring to  FIGS. 6 ,  8  and  9 , in certain embodiments of a frame kit  190 , the first frame member  102  and the second frame member  106  may be rigidly connected to one another to form a frame joint therebetween. The rigid and secure frame joint is typically formed by way of the frame connector assembly  100  being rigidly received substantially within the first frame member  102  such that the connector axis  120  is generally parallel with the first longitudinal axis  104  and the cross member  128  is proximate a first end  194  of the first frame member  102 . Further, the tongue portion  114  is received through the hoop eyelet  132  with the hoop element  122  being in its retention position. 
         [0043]    Referring to  FIGS. 5 ,  12  and  13  for illustration, in embodiments of a frame kit  190 , the cleat element  110  may include a base portion  112  and may be rigidly affixed to the second frame member by way of the base portion  112 . Moreover, in preferred embodiments the tongue portion  114  may extend from the base portion  112  in a direction generally parallel with the second longitudinal axis  108 . Notably, when the second frame member is used as a vertical component of a larger framework, such a configuration allows the first frame member  102  to remain vertically supported by the cleat element  110  (and second frame member) in a stable configuration even when the connector assembly  100  is in its open, unsecured configuration (i.e., the hoop element  122  being in its release position). This provides an important safety feature which is particularly invaluable for protecting personnel during hurried assembly and disassembly of relatively, large, heavy, metal frameworks. 
         [0044]    Referring to  FIG. 12  for illustration, in certain embodiments, the cleat element  110  may include lateral notches  116 , which may be adapted to receive rounded corners between the legs  124  and the cross member  128  of the hoop element  122  once the connector assembly is actuated to move the hoop element to its secure position. Further, referring to  FIG. 13 , the tongue portion  114  may extend at a slight inward angle  200  with respect to the base portion  112  (or to second frame axis  108 ). Such inward angle  200  may preferably be between 5-15 degrees. In certain embodiments, the inward angle  200  may be 5 degrees. These optional cleat features improve both the usability and securement of the connector system. Additionally, referring to  FIG. 10 , the inside face  130  of the cross member  128  may be slightly flattened in order to, for example, increase the contact area between the cross member  128  and the inside face of the tongue portion  114 . 
         [0045]    Referring to  FIGS. 7-9  for illustration, in particular embodiments of a frame kit  190  the first frame end  194  may be beveled at an angle of, for example, approximately 45 degrees with respect to the first frame axis  104 . In other similar embodiments, this angle may preferably be, for example, anywhere between 30 and 60 degrees. Referring to  FIG. 9  for example, in such embodiments, the frame joint may be formed between the first frame end  194  and a lateral wall of the second frame member  106 . 
         [0046]    Referring in particular to  FIGS. 7 and 8 , in certain embodiments of a frame kit  190  the first frame end  194  may beveled at an angle of approximately 45 degrees with respect to the first frame axis  104 , and the second frame end  196  may also be beveled at an angle of approximately 45 degrees with respect to the second frame axis  108 . In such embodiments, a mitered frame joint may be formed between the first and second frame ends. Notably and as illustrated, in such configuration a portion of the connector housing  118  may extend outward of the first frame end  194  and be received by the second frame member  106 , thereby providing further torsional rigidity at the joint. Moreover, in such frame kit configurations, the base portion  112  of the cleat element  110  may be rigidly affixed to an inner surface  198  of the second frame member  106 . A second frame member  106  may include an end cover  192 . 
         [0047]    In particular embodiments of a frame connector assembly, the second frame member may include a detent element  110 . The detent element may take the form of a cleat element  110 , or, for example, it may take the form of a tongue-receiving loop element (not shown) affixed to the second frame member in place of a cleat element. In embodiments, the hoop element  122  may be adapted to be placed in penetrative relationship with the detent element (as shown, for example, in  FIG. 6 ). The penetrative relationship is unsecured when the hoop element  122  is in its release position. The hoop element may be configured to draw the detent element (e.g., tongue portion  114  or a loop element) toward the connector housing  118  and secure the penetrative relationship when the hoop element  122  is moved toward its retention position. In certain such embodiments, such as the ones shown in  FIGS. 1-9 , the connector housing  118 , legs  124  and cross member  128  may collectively define a hoop eyelet  132 , and the penetrative relationship would be defined by receipt of at least a portion of the detent element  110  through the eyelet  132 . In particular alternative embodiments, the cross member  128  may itself include a tongue portion (downwardly facing, for example), the detent element may include a loop portion, and the penetrative relationship would therefore be defined by receipt of the tongue portion through the loop portion. 
         [0048]    Embodiments may be adapted to allow a user to add fabric graphics to the smooth framework by cladding the frame members with an additional small extrusion that accepts a gasket edged fabric graphic panel. By cladding the smooth frame, users can have a bare frame with no graphic that is smooth and clean, or may put graphics on the frame. More importantly, cladded embodiments allow the user to design unique display solutions, including locating a fabric graphic panel on any face of the frame extrusion. This allows the frame to be a design feature if desired. Certain embodiments allow options ranging from showing the entire frame with a graphic, showing part of the frame with graphic, or hiding the frame completely by covering it with graphics. 
         [0049]    Providing cladding for attaching gasket edged fabric graphics to frameworks is typically conventionally done on custom metal and/or wood structures and not on a portable framing systems. Contrastingly, embodiments of the present invention combine the attributes of a portable, smooth frame system with the flexibility of attaching graphics via cladding in any configuration possible. A seller of embodiments herein may clad the frame members, and ship them to the purchaser with the cladding permanently attached. 
         [0050]    While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.