Abstract:
A hanger for connecting a held member to a holding member the hanger having a connection member for holding the held member, a back member which connects to the holding member and a unique connection flange which is used to strengthen the connection to the holding member. The connection flange can either wrap around or under the holding member, and in the preferred embodiment it wraps around the holding member to the side opposite the back member of the hanger. This allows each of the fasteners that connect the hanger to the holding member to be received by the hanger at two points, which better distributes the load throughout the holding member.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a connector used in building construction, and in particular to a structural hanger for suspending a held framing member from a holding framing member in a building. 
     Hangers typically have a stirrup-shaped portion for receiving an end portion of a held framing member, such as a joist, a top flange for connecting the hanger to the support or holding member, such as a truss or a purling, and a back member that connects the stirrup portion to the top flange. 
     The stirrup portion generally comprises a seat member which the held framing member rests upon, and first and second opposite side members that stabilize the held framing member. The first and second opposite side members receive the end portion of the held framing member between them. The first and second opposite side members are generally formed with a plurality of openings for allowing the hanger to be nailed or otherwise attached to the held framing member. This further stabilizes the held framing member and provides uplift resistance. For an example of a hanger with a rather unique stirrup portion see U.S. Pat. No. 4,890,436, granted to Karen W. Colonias for a Multiple Wood Truss Connection. 
     The stirrup portion of the typical hanger is not the only means for supporting the held member taught by the prior art. For example, some hangers eliminate the seat member. They support the held framing member by means of fasteners or bolts received by one or more side member. In these situations the bolts or fasteners provide both bearing support and uplift resistance to the held framing member. For an example of such a hanger see U.S. Pat. No. 4,893,961 granted to Kevin B. O&#39;Sullivan and Arthur L. Troutner for a Joist Hanger. 
     Still other hangers vary from the typical hanger form by eliminating the top flange which connects the hanger to the holding member. See U.S. Pat. No. 4,717,279 granted to Alfred D. Commins on Jan. 5, 1988 for a Bucket Hanger. This is especially true of hangers designed for connecting two plated trusses together. See, for example, U.S. Pat. No. 5,341,619 granted to Brian D. Dunagan and Alfred D. Commins on Aug. 30, 1994 for a Truss Girder Hanger Connection, and U.S. Pat. No. 4,890,436 granted to Karen W. Colonias on Jan. 2, 1990 for a Multiple Wood Truss Connection. These hangers are generally attached to the vertical web member of the carrying truss near the bottom of the truss. Because of their location near the bottom of the vertical web member, an elongated back member would be required to provide a top flange that could hook over the top of the carrying truss. 
     The hanger of the present invention differs from the prior art by providing an improvement to the connection between the hanger and the carrying or holding member. The hanger of the present invention differs from the prior art, first, by providing a connection flange that does not wrap over the top of the carrying or holding member, and, second, by allowing the fasteners that make the connection to the holding member to be in double shear with the hanger. 
     When the carrying member is composed of multiple plies, such as in various nail-plate trusses, and the double-shear configuration is used, the present invention provides improved distribution of the load to the plies in the carrying member. This is because the hanger introduces the load to the fasteners inserted through the carrying member from two sides of the carrying member. This uniform distribution of the load makes it easier to design multiple-ply trusses so that the plies act as one member. 
     SUMMARY OF THE INVENTION 
     It is the object of the present invention to provide an improved hanger for connecting a held member to a holding member. 
     The present invention provides an improved connection between a held member and a holding member by having a unique connection flange that allows the hanger to be used in situations where a top flange cannot be used to connect the hanger to the holding member. 
     The present invention also provides an improved connection between the hanger and the holding member by creating a pair of opposed portions, both of which receive the fasteners that connect the hanger to the holding member. 
     The hanger of the present invention has a connection member for holding the held member, a back member, and a unique connection flange which is used to strengthen the connection of the hanger to the holding member. The connection flange can either wrap around or under the holding member. In the preferred embodiment, the connection flange wraps around the holding member to the side opposite the back member of the hanger. 
     This allows each of the fasteners that connect the hanger to the holding member to be received by the hanger at two points, which better distributes the load throughout the holding member. 
     The hanger of the present invention can be made as a single member. It can also be made with the connection flange formed as a separate “c”-shaped member that attaches to the combined back and connection members. A “c”-shaped connection flange can also be added to the single member embodiment or as an additional connection flange to the embodiment where the first connection flange is already a “c”-shaped member. 
     It is also to be noted that the hanger of the present invention can be used with a variety of structural members. For example, it can be used with standard dimension lumber, engineered lumber, plated wood trusses, truss girders, metal framing members, and engineered metal trusses to name a few examples. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1A is a perspective view of the hanger of the present invention. The longitudinal axis of the holding member connection portion is labeled “y” and the lateral axis of the holding member connection portion is labeled “x”. 
     FIG. 1B is a perspective view of the hanger of the present invention. The hanger is shown with additional openings in the holding member connection portion and the connection flange to receive alternate fasteners. The longitudinal axis of the holding member connection portion is labeled “y” and the lateral axis of the holding member connection portion is labeled “x”. 
     FIG. 2A is a perspective view of the hanger of the present invention in use, connecting a carried truss to the vertical web member of a carrying truss. Blocking is shown disposed between the first and second side members of the connection member. 
     FIG. 2B is a perspective view of the hanger of the present invention in use, connecting a carried truss to the vertical web member of a carrying truss. Blocking is shown disposed between the first and second side members of the connection member. 
     FIG. 3 is a top plan view of the hanger of the present invention. 
     FIG. 4 is a front view of the hanger of the present invention. 
     FIG. 5 is a left side view of the hanger of the present invention. 
     FIG. 6 is a back view of the hanger of the present invention. 
     FIG. 7 is a right side view of the hanger of the present invention. 
     FIG. 8 is a perspective view of a first alternate embodiment of the hanger of the present invention. Some of the fasteners used with the hanger are shown in exploded view. 
     FIG. 9 is top plan view of a first alternate embodiment of the hanger of the present invention. 
     FIG. 10 is a front view of a first alternate embodiment of the hanger of the present invention. 
     FIG. 11 is a left side view of a first alternate embodiment of the hanger of the present invention. 
     FIG. 12 is a back view of a first alternate embodiment of the hanger of the present invention. 
     FIG. 13 is a right side view of a first alternate embodiment of the hanger of the present invention. 
     FIG. 14 is a perspective view of a second alternate embodiment of the hanger of the present invention. 
     FIG. 15 is a top plan view of a second alternate embodiment of the hanger of the present invention. 
     FIG. 16 is a front view of a second alternate embodiment of the hanger of the present invention. 
     FIG. 17 is a left side view of a second alternate embodiment of the hanger of the present invention. 
     FIG. 18 is a back view of a second alternate embodiment of the hanger of the present invention. 
     FIG. 19 is a right side view of a second alternate embodiment of the hanger of the present invention. 
     FIG. 20 is a perspective view of a hanger of the present invention in use. The hanger is shown connected to the vertical web member of a carrying truss. A carried truss is shown being inserted into the connection member of the hanger. Blocking is also shown being set on top of the carried truss. 
     FIG. 21 is a perspective view of a hanger of the present invention in use. The hanger is shown connected to the vertical web member of a carrying truss. A carried truss is shown being inserted into the connection member of the hanger. 
     FIG. 22 is a perspective view of a hanger of the present invention in use. The hanger is shown connected to the vertical web member of a carrying truss. The hanger is shown carrying a typical joist. 
     FIG. 23 is a perspective view of a hanger of the present invention. A carrying truss and a carried joist are shown in phantom. Arrows represent fasteners inserted through the hanger of the present invention and into the carrying truss. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1A, the hanger  1  of the present invention for connecting a held member  2  to a holding member  3  has a back member  4 , a connection member  5 , and a connection flange  6 . The back member  4  has front and back surfaces  7  and  8 , and a holding member connection portion  9  that is substantially planar. The holding member connection portion  9  has a longitudinal axis “y” and a lateral axis “x” disposed orthogonal to the longitudinal axis “y”. The connection member  5 , which is connected to the back member  4 , is disposed at an angle to the holding member connection portion  9 , and extends away from the front surface  7  of the back member  4 . The connection flange  6  is also connected to the back member  4 . The connection flange  6  has a side portion  12  that is substantially planar and is oriented substantially in the direction of the longitudinal axis “y”. The side portion  12  of the connection flange  6  is disposed at an angle to the holding member connection portion  9  and extends away from the back surface  8  of the back member  4 . The side portion  12  of the connection flange  6  is also disposed substantially adjacent to the back surface  8  of the back member  4 . 
     The connection member  5  can be formed as a seat member  13 , having a top surface  14  to provide a bearing surface for the held member  2 . The seat member  13  is oriented substantially in the direction of the lateral axis “x”. 
     The connection member  5  can also be formed as a side member  15 , having a substantially planar portion  16  to provide a stabilizing surface for the held member  2  and an attachment surface for the held member  2 . The side member  15  is oriented substantially in the direction of the longitudinal axis “y”. 
     Where the connection member  5  is formed as a seat member  13 , the seat member  13  can be connected directly to the back member  4  or the connection member  5  can further include a side member  15  that connects the seat member  13  to the back member  4 . 
     As shown in FIG. 1A, in the preferred embodiment, the connection member  5  includes a seat member  13  and two side members  15 . The two side members  15  connect to the seat member  13  and all three connect directly to the back member  4 . 
     As is also shown in FIG. 1A, in the preferred embodiment of the hanger  1 , the connection flange  6  is formed with a back portion  17  that is substantially planar and is oriented substantially parallel to the holding member connection portion  9 . The side portion  12  of the connection flange  6  connects the back portion  17  to the back member  4 . 
     In the preferred embodiment this back portion  17  works with the holding member connection portion  9  to attach the hanger  1  to the holding member  3  by means of a first fastener  18 . The first fastener  18  has a shank  19  and the shank  19  is received by both the holding member connection portion  9  and the back portion  17  of the connection flange  6 . See FIG.  8 . In the preferred form of the invention, this first fastener  18  is a machine bolt having a hexagonal head  20  and a threaded end  21  that receives a nut  22 . See FIG.  8 . The machine bolt  18  is inserted through aligned openings  23  and  24  in the holding member connection portion  9  and the back portion  17  of the connection flange  6  that are dimensioned to receive it. See FIG.  1 A. In the preferred form, a plurality of machine bolts  18  are used. 
     In the preferred embodiment, the hanger  1  is secured to the held member  2  by means of second fasteners  25  having shanks  26  that are received by the connection member  5 . See FIG.  8 . In the preferred embodiment, these second fasteners  25  are nails that are driven into the held member  2  through openings  27  in the side members  15  of the connection member  5 . See FIG.  1 A. 
     The hanger  1  can also be attached to the holding member  3  by means of third fasteners  28  having shanks  29  that are received by the holding member connection portion  9 . See FIG.  8 . These third fasteners  28  would preferably be threaded screws that can be driven directly into the holding member  3  without requiring pre-drilled holes. The side portion  12  and the back portion  17  of the connection flange  6  could also be connected to the holding member  3  by means of threaded screws  28 . See FIG.  8 . 
     In the preferred embodiment, the side members  15  are formed with additional openings  30  for receiving fourth fasteners  31  which are also preferably machine bolts with threaded nuts  32 . See FIG.  8 . As is shown in FIG. 1A, these openings  30  are located near the tops of the side members  15 . These fourth fasteners  31  are preferably used to secure blocking  33  to the hanger  1  which can provide additional uplift resistance when certain truss types are used as the held member  2 . See FIG.  2 A. These fourth fasteners  31  can also be used to support the held member  2  as shown in FIG.  22 . 
     In the preferred embodiment the connection flange  6  is formed as an integral part of the back member  4 . See FIG.  1 A. Preferably, the back member  4  and connection flange  6  are formed from a single piece of  3  gauge ASTM grade steel; however, the connection flange  6  could be formed from a different plate and welded to the back member  4 . 
     The connection flange  6 ′ could also be formed separately from the back member as a “c”-shaped member which would be attached to the back member  4  by means of the first or third fasteners  18  or  28 , during installation. See FIG.  8 . Openings are formed in opposed portions of the “c”-shaped connection flange to receive the first and third fasteners  18  and  28 . 
     Two additional embodiments are also contemplated by the inventor where a “c”-shaped connection flange  6 ′ is used. In the first, the ‘c”-shaped flange is added to the original, preferred embodiment—where the connection flange  6  is formed as an integral part of the back member  4 . See FIGS. 14 through 19. In the second, a connection flange  6 ′ is added to a hanger  1  where the connection flange  6 ′ is already a first separate “c”-shaped member. 
     In the preferred embodiment, the back member  4  is formed with a top edge  34  , a bottom edge  35  and a side edge  36  with the connection flange  6  extending from the side edge  36  of the back member  4 . 
     As shown in FIG. 23, in another embodiment of the present invention, the connection flange  6 ″ can wrap underneath the holding member  3  to which it attaches by means of a basal portion  37 . The basal portion  37  is substantially planar and extends away from the back surface  8  of the back member  4 . The back portion  17  of the connection flange  6 ″, if present, connects to the basal portion  37 . 
     In the preferred form of this embodiment, the basal portion  37  connects to the back member  4  along the bottom edge  35  of the back member  4  and a back portion  17  is present in the connection flange  6 ″. First fasteners  18  are received by the holding member connection portion  9  of the back member  4  and the back portion of the connection flange  6 ″. Second fasteners  25  are received by the connection member  5  to anchor the held  2  member against uplift forces. 
     Fabrication of the preferred hanger  1  of the present invention is as follows. Fabrication of the alternate embodiments is similar and is not repeated. A blank that will form the connection member  5  is sheared from a metal plate. The openings  27  and  30  for the second and fourth fasteners  25  and  31  are formed in the portion of the blank that will become the first and second side members  15 . After the blank for the connection member  5  is cut, the piece is fed into a bending apparatus where the first side member  15  is bent up at an angle of 90 degrees from the seat member  13 , and the second side member  15  is also bent up at an angle of 90 degrees. 
     A blank that will form the back member  4  and the connection flange  6  is also sheared from a metal plate. Fastener openings  23  and  24  for the first fasteners  18  are formed in the portions that will become the holding member connection portion  9  and the connection flange  6 . Fastener openings  38  can also be formed in the back member  4  and the connection flange  6  for the third fasteners  28 . This piece is fed into a bending apparatus where the connection flange  6  is bent up from the back member  4  at an angle of 90 degrees. The side portion  12  and the back portion  17  are then formed by bending the back portion  17  up 90 degrees again from the side portion  12 . 
     The connection member  5  is then welded to the front surface  7  of the back member  4  as shown in FIG.  1 A. 
     As a last step, the hanger  1  is painted to protect it from the elements. 
     Where the connection flange  6 ′ is formed as a separate member from the back and connection members  4  and  5 , it is attached to the back member  4  during installation by means of the first or third fasteners  18  or  28 . 
     Installation and use of the preferred embodiment is described as follows. Installation of the alternate embodiments discussed herein is similar, and is not repeated. A holding member  3  for supporting one end of the held member  2  is erected in a building structure. The other end of the held member  2  can be supported by a similar connection with the hanger  1  of the present invention or by a different connection altogether. The holding member  3  can be any one of a variety of structural framing members. The greatest need for the preferred embodiment is where a joist or a spanning truss needs to be attached to a vertical structural member such as a post, a pillar, or as shown in FIGS. 2A,  2 B,  20 ,  21 ,  22  and  23  the vertical web member of a truss. If the preferred embodiment is to be supported by an elongated horizontal structural member a notch could be formed in the horizontal member to accommodate the connection flange  6 , however, the engineer must bear in mind that forming such a notch in a structural member could greatly change its structural properties. 
     The hanger  1  of the present invention can be attached to the holding member  3  before it is erected or after it is erected. The holding member  3  is prepared by boring holes to receive threaded machine bolts  18 . The openings in the holding member  3  are placed so that they will align with the openings  23  and  24  in the holding member connection portion  9  and the back portion  17  of the connection flange  6 . The preferred hanger  1  is then positioned on the holding member  3 , and threaded machine bolts  18  are passed through the openings  23  in the holding member connection portion  9 , through the holding member  3  and through the back portion  17  of the connection flange  6 . Preferably the threaded machine bolts  18  have a hexagonal head  20  that is disposed near the front surface  7  of the back member  4 . Threaded nuts  22  are threaded to the threaded ends  21  of the machine bolts  18 , and torqued so that the heads  20  of the machine bolts  18  sit tightly against the front surface  7  of the back member  4  and the threaded nuts  22  sit tightly against the connection flange  6 . 
     The held member  2  is then positioned in the connection member  5  such that the held member  2  engages the bearing surface  14  of the seat member  13  and the first and second side members  15  also engage the held member  2 . Nails  25  are then driven through the appropriate openings  27  in the first and second side members  15  and into the held member  2 . If the held member  2  is shaped as is shown in FIG. 20, where the held member  2  does not extend up to the openings  30  in the side members  1   5 , and uplift resistance is desired, then blocking  33  is cut to engage the upper portion of the held member  2  and placed between the first and second side members  15 . The blocking  33  provides additional uplift resistance. Holes are bored in the blocking  33  to receive machine bolts  31  that are inserted through the openings  30  in the first and second side members  15 . The machine bolts  31  are inserted through the appropriate openings in the first and second side members  15  and through the blocking  33 . Preferably, the machine bolts  31  have a hexagonal head  39  and a threaded, opposite end  40 . Threaded nuts  32  are attached to the threaded ends  40  of the machine bolts  31  and torqued so that the connection is tight without crushing the blocking  33 . 
     Testing of the Present Invention 
     A pair of hangers were built according to the preferred single-piece embodiment of the present invention and tested in the laboratory of the assignee. See FIG.  1 A. The hangers was made from 3 gauge ASTM A-570 Grade 33 steel and painted. 
     Each of the connection members of the hangers was formed to closely hold a carried member composed of two 1.75″×15″×18″ TrusJoist MacMillan brand microlam laminated veneer lumber boards. The moisture content of the boards making up the carried member was not measured, but it is usually in the range of 12-15%. These boards were nailed together with approximately twenty 10 d  common nails to form the carried member. For purposes of testing the hangers two more plies of the same material were nailed to sides of the carried member in its center with eight 10 d  common nails on each side to reinforce it. The carried member was meant to simulate the bottom chord of a two-ply, nail-plate truss. 
     Each of the connection flanges of the hangers was formed to closely receive a carrying member composed of three 2″×8″×36″ Douglas Fir-Larch boards nailed together. The moisture content of the boards making up each carrying members was not measured but it is usually 19-21%. The three boards were nailed together with thirty-three 10 d  common nails. Each carrying member was built to simulate the vertical web member of a three-ply, nail plate truss. 
     For testing purposes, the carrying members and the carried member were made stronger than the typical members they were designed to simulate. This was done in an attempt to isolate the failure in the testing to the hangers formed according to the present invention. 
     The hangers were connected to the carried member by ten 10 d  common nails driven through the five smaller openings in the first and second sides members of the connection members. 
     The hangers were connected to their carrying members with five ¾″×6″ machine bolts. The machine bolts were made from A-449 Type 1 steel (Grade 5 bolt). The heads of the machine bolts were disposed on the inner sides of the carrying members against the front surface of the back members of the hangers. A-563 Grade A nuts were attached to the machine bolts and threaded on them until they clamped against the connection flanges of the hangers. No washers were used, although they could be used, if the machine bolt was long enough to allow the nut to fully engage the threads of the machine bolt. 
     Once the hangers were connected to the carrying members, and the carried member, the assembly was placed in the test bed of a compressive testing machine. The compressive force was applied to the middle of the carried member by a ram. Dial indicators were placed at the ends of the carried member to measure the deflection of the carried member with respect to the carrying members under the compressive load. 
     A preload of 10,000 pounds was applied to the carried member and then released to seat the carried member in the hangers and to establish a point of zero deflection for the carried member. 
     Compressive loading was then applied to the carried member at a slow rate and gauge readings were made at 4,000 pound intervals, at the first ⅛″ deflection point for either side of the carried member, and at the ultimate failure point for the assembly. 
     At 18,730 pounds of force, the right side of the carried member deflected ⅛″ from its original point. 
     Ultimate failure occurred at 65,870 pounds when the carried member crushed and the assembly no longer provided meaningful resistance to the compressive force applied.