Abstract:
A longitudinal connection for abutting ends of main grid members of a suspended ceiling system is provided where each, of the main grid members have a vertical web portion and a horizontal flange extending across a bottom of the web portion. The longitudinal connection comprising retaining means on the web portion of each of the main grid members adjacent the abutting ends providing an upper and a lower channel. A plate member having opposite first and second sides is slidable within the upper and lower channels on the ends of each of said main grid members. Moveable pin members are provided on the plate member where the pin members are biased to the web portion of the main grid members. Holes on the retaining means on the web portion of each of the main grid members adjacent the abutting ends providing an upper and a lower channel are positioned to receive the pin members when the abutting ends of main grid members are aligned. This results in the plate member pulling the main grid members together at the abutting ends.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to suspended ceiling systems and in particular improved connections for end to end connection of the main grid members of such systems and for connection of cross members to the main grid members. 
       BACKGROUND OF THE INVENTION 
       [0002]    Suspended ceiling systems are well known and are commonly used to conceal piping, wiring or ductwork beneath the overhead structure. The suspended ceiling grid system comprises wall angle mouldings, main grid members (main tees) running in one direction of the ceiling with cross members (cross tees) connected to adjacent grid members to form the grid pattern. The most common grid patterns are rectilinear or square grids although non-rectilinear patterns can be used. Each grid defined by the main grid members and cross members is typically filled with a lightweight acoustic ceiling tile or panel which is suspended within the grid. 
         [0003]    The main grid members or tees are suspended from the floor above by wire or plastic fasteners and span the length of the room. If a single strip of the main grid member is not long enough to span the entire room two or more main tees are connected end to end. 
         [0004]    Different methods of connection of the main grid members are known. For example U.S. Pat. No. 6,523,313 shows a an end-to-end connection of main grid members in a ceiling grid. A pocket is formed about an opening in the web of a first main grid member. A clip is secured to one side of the end of the first main grid member. A forward end of the clip is clamped within a pocket formed on the second main grid member. A corresponding clip on the opposite side of the end of the second grid member is clamped within the pocket formed on the first grid member. While the connection is intended to be disengaged when required the pockets must be opened first which is not easy to do. 
         [0005]    Another example of a method of connection is illustrated in U.S. Pat. No. 6,729,100. In this patent purports to provide a connector for a main tee of a suspended ceiling grid that has improved self-aligning and connection force properties. The connector has an end tab with a forward portion bent at a lead angle and a receiving pocket with an outwardly flared entrance that, with an opposed identical connector, cooperate to provide smooth horizontal alignment. The end portion, additionally, includes an edge profile that vertically aligns itself with the receiving pocket of the opposed connector. The receiving pocket includes a spring-like resilient wall that limits the assembly force to overcome interference with projecting lock lances even when the connectors are nearly out of dimensional tolerance. The spring-like pocket wall, shape of the lock lance, and reinforcing beads contribute to an improved audible click signalling that a connection has been completed. The lock lance works with a relief groove to augment self-alignment of the connectors. 
         [0006]    There remains a need for a simple, fast and secure method of making longitudinal connections between the abutting ends of the main grid members. 
         [0007]    One method of connection between the cross members and main grid members is to attach a clip by riveting or other suitable means to the end of the cross member so that it extends beyond the end of the cross member. The clip includes a tab which is adapted to pass through a slot provided in the web or vertical portion of the main grid member to secure the cross member in place as shown for example in U.S. Pat. No. 4,161,856; 4,389,828; 4,499,697 and 5,154,031. There is an ongoing need to provide a simple, fast and secure method of making linear connections between the cross members and main grid members without tilting or twisting the cross members. 
       SUMMARY OF THE INVENTION 
       [0008]    It is an object of the present invention to provide a suspended ceiling grid system that can be easily assembled or disassembled without damaging the main grid members and cross members permitting them to be reused. 
         [0009]    Accordingly in one embodiment the present invention provides a longitudinal connection for abutting ends of main grid members of a suspended ceiling system. Each of the main grid members have a vertical web portion and a horizontal flange extending across a bottom of the web portion. The longitudinal connection comprises retaining means on the web portion of each of the main grid members adjacent the abutting ends providing an upper and a lower channel. A connecting plate member having opposite first and second sides is slidable within the upper and lower channels on the retaining means on the ends of each of said main grid members. Moveable pin members are provided on the plate member where the pin members are biased to the web portion of the main grid members. Holes on the retaining means on the web portion of each of the main grid members are positioned to receive the pin members when the abutting ends of the main grid members are aligned. This results in the connecting plate member pulling the main grid members together at the abutting ends. 
         [0010]    In another embodiment the invention provides a method of forming a longitudinal connection for abutting ends of main grid members of a suspended ceiling system, wherein the main grid members have a vertical web portion and a horizontal flange extending across a bottom of said web portion. The method comprises (a) providing retaining means on the web portion of each of the main grid members adjacent the abutting ends to form an upper and a lower channel (b) providing a connecting plate member having opposite first and second sides slidable within the upper and lower channels on the retaining means on the ends of each of said main grid members (c) aligning the abutting ends of main grid members (d) sliding the plate member in the upper and lower channels of the retaining means on each grid member until moveable pin members on said connecting plate member are aligned with and are received in holes on the retaining means on the web portion of each of the main grid members whereby said connecting plate member pulls the main grid members together at said abutting ends. 
         [0011]    In another aspect the present invention provides a linear connection for connecting cross members to the main grid members of a suspended ceiling system, each of said main grid members and the cross members having a web portion, the linear connection comprising: (a) means on the web portion of each of the cross members adjacent their ends providing an upper and a lower channel (b) a clip having opposite first and second sides slidable within the upper and lower channels on the ends of each of said cross members to permit a linear connection of the cross members to the main grid members. 
         [0012]    Further features of the invention will be described or will become apparent in the course of the following detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE INVENTION 
         [0013]    In drawings which illustrate by way of example only one embodiment of the invention, 
           [0014]      FIG. 1  is a perspective view of the longitudinal connection of two main grid members utilizing connecting blocks attached to the ends of the main grid members and a connecting plate in accordance with the present invention. 
           [0015]      FIG. 2  is a perspective view of the linear connection of two cross members with a main grid member utilizing a block on the ends of each cross member and a slidable clip in accordance with the present invention. 
           [0016]      FIG. 3  is a perspective view of a section of the connecting block attached to the abutting ends of the main grid members of  FIG. 1 . 
           [0017]      FIG. 4  is a top view of the connecting plate of  FIG. 1  with spring arms. 
           [0018]      FIG. 5  is a side view of the slideable clip of  FIG. 2 . 
           [0019]      FIG. 6  is a perspective view of the block of  FIG. 2 . 
           [0020]      FIG. 7  is a partially exploded view of the cross member of  FIG. 2 . 
           [0021]      FIG. 8  is cross section view of another embodiment of the main grid member and connecting block according to the present invention. 
           [0022]      FIG. 9  is a plan view of another embodiment of the spring member attached to the connecting plate shown in  FIG. 1 . 
           [0023]      FIG. 10  is a top plan view of another embodiment of the clip shown in  FIG. 2 . 
           [0024]      FIG. 11  is a cross section of the clip of  FIG. 10  through B-B. 
           [0025]      FIG. 12  is a side view in cross section of the clip of  FIGS. 10 and 11 . 
       
    
    
       [0026]    Similar references are used in different figures to denote similar components. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0027]    Referring now to the figures in detail,  FIG. 1  illustrates a longitudinal connection according to the present invention between the abutting ends of one main grid member, generally indicated at  11  and a second main grid member, generally indicated at  12 . In the embodiment illustrated both main grid members  11 ,  12  each have an inverted T cross section having a web portion  13 ,  14  with a horizontal flange  15 ,  16  extending perpendicular from the base of the web portion  13 ,  14 . While the embodiment illustrated in the Figures shows the present invention used in association with main grid members having an inverted T cross-section, it should be appreciated that the present invention is applicable to other shapes of main grid members. The grid members  11 ,  12  may be made of conventional materials and formed by conventional techniques or may be made by extrusion molding aluminum or zinc or other suitable material. 
         [0028]    In order to form a longitudinal connection according to the present invention between the abutting ends of the main grid members  11 ,  12  retaining means comprising in this embodiment a connecting block  21 ,  22  is attached to a face  15 ,  16  of the web portion  13 ,  14  adjacent the abutting ends  17 ,  18  of each of the main grid members  11 ,  12 . The connecting blocks  21 ,  22  can be attached by a riveting or welding means not shown in  FIG. 1 . As best shown in  FIG. 3 , each connecting block  21 ,  22  has a generally flat rectangular base portion  23  with opposite sides  24 ,  25 . The opposite side  24  of the base portion  23  has a series of right angle flanges  26 ,  27 ,  28 ,  29  that together form a channel  211 . A similar series of flanges  26 ′,  27 ′,  28 ′,  29 ′ on the opposite side  25  form another channel  212 . On the base portion  23  of connecting blocks  21 ,  22  are holes  210  and  220 . The abutting ends  17 A,  18 B of connecting blocks  21 ,  22  are preferably beveled at  200 ,  201  as shown in  FIG. 1 . It is possibly to indent the face of the web portion to which the connecting blocks  21 ,  22  are connected so that when connected as described below the longitudinal axis of the connection is aligned as close as possible with the longitudinal axis of main grid members  11 ,  12 . (see  FIG. 8 ) 
         [0029]    As seen in  FIG. 1  and  FIG. 4 , a connecting plate member  31  shaped and sized to fit in the channels  211 ,  212  on each of connecting blocks  21 ,  22  when the abutting ends  17 ,  18  of main grid members  11 ,  12  are aligned longitudinally. Connecting plate  31  in the embodiment illustrated is generally rectangular with opposite ends  33 ,  34  and opposite sides  35 ,  36  and having slight octagonal characteristics at its opposite ends  33 ,  34  to be aligned with channels  211 ,  212  on connecting blocks  23 ,  24 . The opposite sides  35 ,  36  of connecting plate  31  slide in channels  211 ,  212 . An outwardly extending flange  300  at each opposite end  33 ,  34  of the connecting plate  31  act as handles to enable the user to slide the connecting plate  31  through the channels  211 ,  212  in both connecting blocks  21 ,  22 . Connecting plate  31  is provide with pin members that cooperate with features provided on connecting blocks  23 ,  24  to retain the main grid members in abutting connection. In the embodiment illustrated the pin members on connecting plate  31  comprises a pair of pins  321 ,  322  that project from the back side  37  of connecting plate  31 . The pins  321 ,  322  are positioned to fit within holes  210 ,  221  on connecting blocks  21 ,  22  when the main grid members  11 ,  12  are abutting. In order to permit connecting plate  31  to slide within channels  211 ,  212 , pins  321 ,  322  project through holes  38 ,  39  in the connecting plate  31 . The ends of pins  321 ,  322  that extend to the front side  40  of connecting plate  31  are connected to the ends of spring member  32 . In the embodiment illustrated pins  321 ,  322  and spring member  32  are a single integral piece of resilient material. The mid point of spring member  32  is affixed to the front side  40  of connecting plate  31 . This results in spring member  32  and pins  321 ,  322  having an “M-shaped” form (see  FIGS. 4 and 9 ), wherein the two ends  321 ,  322  of the spring are biased to extend through the holes  38 ,  39  in the connecting plate  31  and into locking engagement with holes  210 ,  220  on connecting blocks  21 ,  22 . In the embodiment shown the mid point  41  of the spring member  32  is fixed within a middle hole  42  located in connecting plate  31 . Spring member  32 , is preferably made out of a resilient metallic material. 
         [0030]    In the embodiment shown in the Figs. the spring member  32  has two spring arms  32 A,  32 B. As noted above the spring arms bias pins  321 ,  322  within holes  210 ,  220  in connecting blocks  21 ,  22 . With pins  321 ,  322  engaged within holes  210 ,  220  on connecting blocks  21 ,  22  the main grid members are retained in longitudinal abutment. 
         [0031]    The present invention provides a simple, fast and secure connection between the abutting ends of the main grid members. One end  34  of connecting plate  31  is slid into position within channels  211 ,  212  on connecting block  21  on main grid member  11 . The bevel  200  at the end  17  of connecting block  21  pushes pin  321  away from the back side of connecting plate  31  so that connecting plate  31  can be slid within channels  211 ,  212 . Connecting plate  31  can be slid until pin  321  aligns with and is pushed into hole  210 . The other main grid member  12  can then be aligned so the other end  33  of connecting plate  31  slides into position within channels  211 ,  212  on connecting block  22  on main grid member  12 . The bevel  201  at the end  18  of connecting block  22  pushes pin  322  away from the back side of connecting plate  31  so that connecting plate  31  can slide within channels  211 ,  212 . Connecting plate  31  can be slid until pin  322  aligns with and is pushed into hole  220 . Alternatively the ends  17 ,  18  of main grid members  11 ,  12  can be aligned, then connecting plate  31  slid into the channels  211 ,  212  on either connecting block  21  or  22  then slid along until it slides into the channels on the other connecting block. Although the Figures show the longitudinal connection of two main grid members, a section of desired length can be formed by connecting the abutting ends of numerous grid members using a multiplicity of connecting plates  31 . To provide greater rigidity where there are two or more connections, the connecting blocks are attached to opposite faces of the main grid member at opposite ends of the main grid member. 
         [0032]    To disassemble the longitudinal connection, simply pull spring arms  32 A,  32 B so pins  321 ,  322  move toward the face side of connecting plate  31  to disengage pins  321 ,  322  from holes  211 ,  220  respectively. Once disengaged, connecting plate  31  can be slid out of engagement with channels  211 ,  212  on either one of connecting block  21 ,  22  so that main grid members can be separated. 
         [0033]    In another embodiment the present invention provides for a method of connection of the cross members to the main grid members. Referring to FIGS.  2  and  5 - 7  cross members  41 ,  42  are shown connected to a main grid member  1  in accordance with the present invention. The cross members  41 ,  42  each have an inverted T cross section having a web portion  43 ,  44  with a horizontal flange  45 ,  46  extending perpendicular from the base of the web portion  43 ,  44 . The connection is formed by inserting a clip  51  with a tab  510  through a slot  70  provided in the web portion  2  of main grid member  1  not unlike conventional methods. However the design of the clip  51  of the present invention permits an improved linear connection that is simple, fast and secure. 
         [0034]    In order to form a connection according to the present invention between the ends of the cross members  41 ,  42  to main grid member  1  a block  52  is attached to a face of the web portion  43 ,  44  adjacent the ends  47 ,  48  of each of the cross member  41 ,  42 . The blocks  52  can be attached by a riveting or welding means not shown. As best shown in  FIG. 6 , each connecting block  52  has a generally flat rectangular base portion  53  with opposing sides  54 ,  55  having a C-shaped cross section to form grooves  56 ,  57 . While the embodiment illustrated in the Figures shows the present invention used in association with main grid members and cross members having an inverted T cross-section, it should be appreciated that the present invention is applicable to other shapes of main grid members and cross members. The end  47  of left cross member  41  and the end  48  of right cross member  42  are connected through a slidable locking interaction between clip  51  on the proximal side of block  52  mounted on right cross member  42  and a corresponding block  52  mounted on the distal side of left cross member  41 . 
         [0035]    As shown in  FIG. 7 , clip  51  is formed from a sheet material with upturned edges  65 ,  66  and end  67 . The head  68  of clip  51  is tapered with a tab or barb  510 . Tab  510  has spring-like properties, being able to be pushed from a clearance position to a locking position. Clip  51  is sized and shaped to slide within grooves  56 ,  57  on block  52 . 
         [0036]    To connect the cross member  41 ,  42 , the clip  51  is inserted into the grooves  56 ,  57  of block  52  with the tab or barb  510  projecting away from block  52 . When the tab or barb  510  is pushed through the aperture in main grid member  1 , the tab  510  is depressed and once tab  510  passes through the aperture it returns to the extended or locking position with the edge of the aperture. The upturned end  67  of clip  51  acts as a limit block and, together with the tab  510  in locking position, prevents clip  51  from moving past block  52 . As a result, left cross bar  41  and right cross bar  42  become perpendicularly contiguous with section bar  1 . To disassemble the perpendicular connection, the user should manually push down on barb  510  thereby allowing clip  51  to slide back out of the aperture in section bar  1 . 
         [0037]    On the opposite end  63  of cross member  42  another block  62  and clip  61  are mounted to the opposite face of the web of the cross member from block  52 . Similarly as noted above block  52  on cross member  41  adjacent the end connecting to main grid member  1  is on the opposite face of the web portion of cross member  41  than the block  52  on the face of the web portion of cross member  42 . 
         [0038]    Referring to  FIG. 5 . projections  511  on the back side of block  52  may be provided to match with the positioning holes  521  on block  52  in  FIG. 6 , so as to facilitate the operation as the clip  51  is inserted into position. 
         [0039]      FIG. 8  shows another embodiment of the main grid member  80  with retaining means, in the form of a connecting block  81  riveted to the web portion  82  of grid member. The connecting block  81  provides channels  83 ,  84  for the connecting plate (not shown). 
         [0040]      FIG. 9  shows the spring member  32  with ends that form pins  321 ,  322 . 
         [0041]      FIGS. 10 ,  11  and  12  show another embodiment of a clip  100  for making a linear connection between the cross members and main grid members of a suspended ceiling system. The clip slides within the block  52  on the cross members. 
         [0042]    Numerous modifications, variations, and adaptations may be made to the particular embodiments of the invention described above without departing from the scope of the invention, which is defined in the claims.