Abstract:
A connector is disclosed for interconnection of disconnected truss members. The connector comprises an elongate sheet metal plate including a first plate portion and a second plate portion. The first plate portion has nailing teeth adapted to be driven into a truss member for permanently attaching the first plate portion to one member. The second plate portion has nail holes formed in it for receiving nails to permanently attach the second plate portion to another of the truss members. The second truss plate portion is substantially free of nailing teeth at the peripheries of the nail holes, but has at least one nailing tooth for temporary connection of the second plate portion to the truss during transport. The truss can be collapsed and transported to the building site with the truss members disconnected. The truss can then be erected and the truss members connected by positioning the second plate over a face of the other truss member and securing the second plate to the other truss member by driving nails through the holes.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a hinge and a hinge joint for hingedly connecting structural frame members, more particularly to a hinge and hinge joint of a collapsible structural frame member. 
     The use of roof trusses manufactured in a truss plant and shipped to a building site for installation in a structure is commonplace. Because some trusses are too large for transport over public streets and highways, truss manufacturers add hinged connections within the truss so that the truss can be collapsed to a smaller (typically shorter) size for shipping. To assemble such a truss, the truss manufacturer positions truss members and nailing plates for proper engagement with one another. Integral teeth on the nailing plates, including some nailing plates having a hinge, are pressed into the truss members by a press, such as conventionally used for the driving of nailing plates to form the truss. An example of a hinged connector used in collapsible truss manufacture is shown in co-assigned U.S. Pat. No. 5,553,961, the disclosure of which is incorporated herein by reference. The manufacturers then collapse the truss structure at the hinged joints for transport to the building site. 
     Certain members of the truss, typically the members forming the peak of the truss, are intentionally left unconnected in the collapsed configuration of the truss. Each of the peak members is attached by a hinged nailing plate to another truss member, as is necessary to permit folding down the peak members to a collapsed position. However, the hinge of the nailing plate combined with the lack of connection of the peak members to each other allows the peak members to move during transport. Movement of the peak members during transport is undesirable and can cause damage to the truss. At the building site, the truss is erected and the peak members are connected. However, conventionally no nailing plate is used to make the connection. In any event a nailing plate would be very difficult to manually drive into the peak members so as to make an adequate connection and provision of a press at the site is impractical. Thus, the hinged connectors of U.S. Pat. No. 5,553,961 are not practical for connecting previously unconnected members at the building site. Often one or two pieces of plywood are used to connect the peak members. The plywood overlies the peak members and is separately nailed to both of them. There is no way to know whether the connection made is adequately strong. The quality of the connection will inherently be different for all peak connections. 
     SUMMARY OF THE INVENTION 
     Among the several objects and features of the present invention may be noted the provision of a connector which facilitates the use of a collapsible prefabricated frame structure; the provision of Such a connector which promotes secure interconnection of frame structure members at a construction site; the provision of a connector which permits temporary attachment of one collapsed frame structure member to another frame structure member for shipping; the provision of a connector which permits ready disengagement of a frame structure member from another frame structure member such that the frame structure member can pivot to its erect position and be permanently secured; the provision of a connector which permits permanent attachment of a first plate portion to the member during manufacture and permits permanent attachment of the second plate portion to an adjacent member at the building site; and the provision of such a connector that is economical to manufacture and easy to use. 
     Further among other objects and features of the present invention may be noted the provision of a joint and a truss incorporating the aforementioned connector. 
     Generally, a connector for interconnection of disconnected truss members comprises an elongate sheet metal plate including a first plate portion and a second plate portion. Each plate portion has one face as its outside face and another face as its inside face. The first plate portion has nailing teeth struck from the first plate portion and extending from the inside face of the first plate portion. The nailing teeth are adapted to be driven into one of the truss members for permanently attaching the first plate portion to one member. The second plate portion has nail holes formed therein for receiving nails to permanently attach the second plate portion to another of the truss members. The second truss plate portion is substantially free of nailing teeth at the peripheries of the nail holes. The truss can be collapsed and transported to the building site with the truss members disconnected. The truss can be erected and the truss members connected by positioning the second plate portion over a face of the other truss member and securing it to the other truss member by driving nails through the holes in the second plate portion. 
     In another aspect of the present invention, a joint connects two coplanar structural members. Each member has first and second generally flat faces. The joint includes the structural members and two connectors as described above. 
     In another aspect of the present invention, a truss generally comprises interconnected truss members including first and second truss members hingedly connected to others of the truss members for pivoting movement between a collapsed position in which the truss can be transported to the building site and an exact position in which this truss is configured for installation into a structure. The truss further includes a connector adapted to interconnect the first and second truss members. The connector is as described hereinabove. 
     Other objects and features will be in part apparent and in part pointed out hereinafter. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front elevational view of a simple wooden roof truss having connectors of the present invention; 
     FIG. 2 is the elevational view of FIG. 1 but showing the truss in its collapsed position; 
     FIG. 3 is a fragmentary front elevational view of a peak of the truss; 
     FIG. 4 is an enlarged bottom view of the peak of FIG. 3 with portions of wooden truss members broken away to show attachment of the connectors to the members; 
     FIG. 5 is a fragmentary front elevational view of the truss of FIG. 2, showing the temporary attachment of one truss member to another; 
     FIG. 6 is an enlarged bottom view of the truss in FIG. 5, with portions of a wooden truss member broken away to show temporary attachment of the connector to the wooden truss member; 
     FIG. 7 is an elevational view of an outside face of a connector of this invention; 
     FIG. 8 is an elevational view of an inside face of a connector of FIG. 7; and 
     FIG. 9 is an enlargement of the right-hand part of FIG  7 . 
     Corresponding reference characters indicate corresponding parts throughout several views of the drawings. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings and specifically to FIG. 1, an erected truss constructed according to the principles of the present invention is indicated generally at  21 . In a conventional roof structure (not shown), multiple, parallel wooden roof trusses provide structural support for a roof. The truss  21  shown is a simple roof truss formed of truss members (broadly “structural frame members”) including a left upper chord  23  and a right upper chord  33  angled upwardly and inwardly meeting at a peak joint  43  of the roof structure. A lower chord  45  joins the lower ends of the upper chords  23 ,  33 , completing the truss structure  21 . The lower chord  45  attaches to the upper chords  23 ,  33  with conventional connector plates  47 . The number and orientation of the truss members may vary from the preferred embodiment without departing from the scope of the invention, as the hinged connector of the present invention, generally indicated at  71 , is readily applicable to alternate truss designs. For example, the truss members typically further include interior web members (not shown) extending between two of the (upper and lower) chords to strengthen the truss. In addition, the truss members may include some metal chords or webs (not shown). 
     For the purposes of this description, each piece of lumber incorporated as a truss member is of rectangular cross-section having two narrow sides and two wide sides. The lumber surfaces incorporating the two wide sides of the truss members will be called faces. Collectively, the members of the truss of FIG. 1 each have a first face  53  and an opposite second face  55 , corresponding to the wide sides of the member. 
     The left upper chord  23  comprises two separate elements, an upper left element  25  and a lower left element  27 . A pair of conventional hinged connector plates  61  (only one is shown) pivotally connects these elements  25 , 27 . The hinged connector plates  61  have two plate portions pivotally connected as disclosed in co-assigned U.S. Pat. No. 5,553,961. Each plate portion has integral nailing teeth struck from it. A first connector  61  attaches to the first faces  53  of the upper left element  25  and the lower left element  27 , while a second connector (not shown) attaches to the second faces  55  of the upper left element and the lower left element. Once attached, the upper left element  25  pivots freely from its erect position to a collapsed position adjacent the lower chord  45 , as shown in FIG.  2 . Similarly, the right upper chord  33  comprises an upper right element  35  and a lower right element  37  connected about a pair of conventional hinged connector plates  61 . The upper right element  35  similarly pivots about the connector plate  61  from its erect position to a collapsed position adjacent the upper left element  25  as shown in FIG.  2 . 
     The ends  29  of the upper left element  25  and the upper right element  35  are cut at an angle such that when the upper chords  23 ,  33  are in their erect position, the ends meet in generally flush engagement, transferring the load between the chords over the entire area of the peak joint  43  (FIGS.  3  and  4 ). A pair of connector plates  71  of the present invention join the left upper chord  23  and right upper chord  33 . The connector plates  71  of the present invention are hinged like the conventional hinged connector plates  61 . 
     The first connector plates  71  each comprises a first plate portion  77  and a second plate portion  79 . The first plate portion  77  has a plurality of nailing teeth  81  for permanently mounting the connector to one of the upper chords  23 ,  33 . The second plate portion  79  has five nail holes  83  for receiving nails  87  and permanently nailing the second plate portion to the other of the upper chords  23 ,  33 . A first of the connector plates  71  is designated by  75  and a second of the connector plates is designated by  85 . The first connector plate  75  has the teeth  81  of its first plate portion  77  pressed into a front face of the upper left chord, and the second plate portion  79  is nailed to a front face of the right upper chord  33 . The second connector plate  85  attaches oppositely as compared with the first connector plate  75 , with its first plate portion  77  pressed into the rear face of the right upper chord  33  and its second plate portion  79  nailed into the left upper chord  23 . The nailing teeth  81  and nails  87  create a permanent angled joint  43  that fixedly holds the right and left upper chords  23 ,  33  in proper position, forming an erect truss  21 . It is envisioned that a connector plate (not shown) could be formed with the plate portions in a fixed angular orientation (i.e.: not hinged) corresponding to the angle of the peak. 
     When collapsed, the first connector plate  75  temporarily secures the collapsed upper left element  25  to the lower chord  45  by four nailing teeth  81 ′. In addition, the second connector plate  85  temporarily secures the collapsed upper right element  35  to the collapsed upper left element  25  by four nailing teeth  81 ′. These nailing teeth  81 ′ provide adequate securement of the members for temporary connection during transport of the collapsed truss  21 , while allowing ready disengagement of the members upon delivery of the collapsed truss to the building site. The nail holes  83  are not used at the truss manufacturing facility for temporary attachment of the connector plates  71  (FIGS.  5  and  6 ). Instead, the four nailing teeth  81 ′ are pressed or driven into the lower chord  45 , providing adequate retention for transit. 
     Referring to FIGS. 7 and 8, each plate portion  77 ,  79  has an outside face  101  and an inside face  103 . The inside faces  103  of the first and second plate portions  77 ,  79  engage the truss members, while the outside faces  101  of the portions face outwardly from the truss members. The first and second plate portions  77 ,  79  each comprise a generally flat body portion  105  and a generally flat extension  107  from the body portion. The extensions  107  overlap such that the outside face  101  of the extension of the first plate portion  77  is in engagement with the inside face  103  of the extension of the second plate portion  79 . 
     The overlapped extensions  107  are interconnected for pivotal movement of the first and second plates  77 ,  79  relative to the other about an axis A perpendicular to the plates. The first plate portion  77  has a circular opening  111  in its extension  107 . The second plate portion  79  also has a circular opening  113  in its extension  107  and an annular flange  115  projecting outwardly from the second plate  79  around the opening. The flange  115  fits through the opening  111  in the first plate portion  77 , and a rim  117  of the flange is deformed to extend radially outwardly on the inside of the extension  107  around the opening. The rim  117  locks the plate portions  77 , 79  together but permits the overlapped extensions  107  to pivot relative to each other about the axis A perpendicular to the plates. 
     The first plate portion  77  has a generally flat rectangular body portion  105  having the nailing teeth  81  struck from the portion extending from its inside face  103 . The teeth  81  are struck from the body portion  105  of the plate in pairs leaving a slot  119  in the plate for each pair of teeth  81 . The slots  119  extend transversely with respect to the plate  77  and the teeth  81  extend perpendicularly to the plate at the ends of the slots. Once the teeth  81  are pressed into a wooden truss member, they are permanently affixed to the member and are not easily removed without damaging the plate  77  or the truss member. The first and second plate portions  77 ,  79  including the bodies  105  and the extensions  107  thereof, each are of generally rectangular form having parallel side edges  121 , an outer end edge  123 , and an inner edge  125 . The corners of the plate at its outer end are notched as indicated at  131 . Also, the plates  77 ,  79  have notches  131  in their side edges  121 , these notches being aligned transversely of the plates and defining narrow bridges  135  of the plates between and interconnecting the main body  105  of the plate and its extension  107 . The notches  131  are produced in the manufacture of plates  77 ,  79  from coiled sheet strip to provide for indexing forward of the strip at plate length intervals. 
     In the preferred embodiment, four nailing teeth  81 ′ formed in the outer end edge  123  of the second plate portion  79  temporarily connect the connector  71  to a truss member. It is contemplated that a different location or number of teeth  81 ′ could be used without departing from the scope of the invention, provided the second plate portion  79  is substantially free of nailing teeth at the peripheries of the nail holes  83 . Generally, there should be enough nailing teeth  81 ′ for secure, temporary attachment, but not so many as to make non-destructive detachment impractical. The nail holes  83  arranged on the second plate portion  79  allow for permanent connection of truss members. In the preferred embodiment, five nail holes  83  allow attachment of the second plate portion  79  to a truss member with nails  87 . Careful selection of the location and number of the holes  83  ensures the connection is sufficiently strong for permanent attachment of the second plate portion  79  to a truss member. However, the number of holes  83  could be other than five without departing from the scope of the present invention. Additionally, the nail hole pattern is asymmetric about a longitudinal axis B of the second plate portion  79 , such that two connectors  71  may attach to opposite faces of a single truss member wherein the second plate portion of the first and second connector plates engage the same part of a truss member. Because the nail holes  83  are asymmetric, the nails  87  entering one face of the truss member will not interfere with nails entering the opposite face. 
     In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained. 
     When introducing elements of the present invention or the preferred embodiment(s) thereof, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. 
     As various changes could be made in the above without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.