Patent Abstract:
A seating assembly with a base, a seat and a back which have interlocking features, and a strap latch removeably securing the back to the base with a portion of the seat sandwiched therebetween. The strap latch comprises a strap affixed to one component, with a latch attached to its free end, and a catch member affixed to another component. The seat may also be configured to appear horizontal but to have a rearward incline when occupied, by affixing the seat webbing to a fixed forward member and a floating rear member, and attaching the floating member to a fixed rear member via straps, wherein the straps and the seat webbing have sufficient elasticity to allow the floating member to be depressed when a downward force is applied to the seat.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable. 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     REFERENCE TO SEQUENCE LISTING, A TABLE OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX 
     Not applicable. 
     BACKGROUND OF THE INVENTION 
     The invention is in the field of seating design and construction. 
     BRIEF SUMMARY OF THE INVENTION 
     The invention comprises a seating assembly of first and second seating components releasably secured together without the need for tools, by at least one strap latch. The strap latch comprises a strap with one end of the strap affixed to the first component and the other end of the strap affixed to a latch. The latch of the strap latch releasably engages a catch which is affixed to the second component. 
     Preferably, three or more components are releasably joined without the need for tools by using a combination of one or more component interlocking features and at least one strap latch. Also in a preferred embodiment, adjacent seating units can be ganged together using a strap latch. 
     The seating assembly may also feature a seat support with fixed forward and rear frame members, and a floating rear frame member attached to the fixed rear frame member with at least one strap, with the seating web attached along its front edge to the fixed forward frame member and along its back edge to the floating rear frame member. This seat support appears to be horizontal when unoccupied, but the seat webbing and strap have sufficient stretch such that when a downward force is applied to the seat, the floating rear frame member is depressed, such that the seat has a rearward incline. This allows for a seat that appears flat, but feels inclined to the occupant. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front perspective view of a chair with a tablet arm, completely assembled, but without cushions, while ganged to a second upholstered chair; 
         FIG. 2  is a detailed top perspective view of a latch with the strap attached. 
         FIG. 2A  is a detailed view of a latch and a catch in the ready position, showing alignment of the strap; 
         FIGS. 3A-3C  are detail views of the latch in its various positions as it is pivoted over center into its locked position in the catch, with the strap not shown, for purposes of clarity; 
         FIG. 4  is a perspective view of the base, configured to receive a chair and a tablet arm; 
         FIG. 5  is a perspective view of a tablet arm; 
         FIG. 6  is a top perspective view of the interior of the tablet arm, and the H-shaped brace and strap latch; 
         FIG. 7  is a side perspective view of the base with the tablet arm installed thereon; 
         FIG. 8  is a top perspective view of the base and the tablet arm, with the strap latch in the ready position; 
         FIG. 9  is a top perspective view of the base and the tablet arm, with the strap latch in the latched position; 
         FIG. 10  is a top view of the seat; 
         FIG. 11  is a bottom perspective view of the seat; 
         FIG. 12  is a top perspective view of the base, the tablet arm and the seat; 
         FIG. 13  is a detailed side view of the side rail of the seat and its interaction with the base of the chair; 
         FIG. 14  is a slightly elevated side perspective view of the base, tablet arm and seat support, as it looks when the chair is un-occupied; 
         FIG. 15  is a slightly elevated side perspective view of the base, tablet arm and seat support, as it looks when the chair is occupied; 
         FIG. 16  is a bottom perspective view of the back; 
         FIG. 17  is a top perspective view of the chair with the back lined up for attachment to the base and the seat; 
         FIG. 18  is a bottom perspective view of the base, the seat and the back, showing the strap latch and order of stacking and interlocking of the elements; 
         FIG. 19  is a cross sectional view of a chair; and 
         FIG. 20  is a bottom perspective view, showing the ganging of a first chair to a second chair. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  shows a ganged seating assembly  30  of two preferred embodiment chair assemblies  32  and  32 ′, one of which ( 32 ) is shown un-upholstered and with an optional tablet arm  130 , and the other of which ( 32 ′) is shown upholstered. Each chair assembly  32  includes a base  90  ( FIG. 4 ), an interlocking seat  140 , a back  160 , and an optional tablet arm  130  ( FIG. 1 ). In the preferred embodiment, these components are modularly connected in an interlocking manner, without the need for tools and are secured together by one or more strap latches  50  ( FIGS. 2-3 ). Strap latches  50  are also used to attach, or “gang” one chair assembly  32  to an adjacent chair assembly  32 ′ to form a seating assembly  30  which is capable of being configured in a custom manner ( FIG. 1 ). 
     Strap latch  50  comprises a strap  52  secured to one chair assembly  32  component, with a latch  54  at one end of the strap  50 , which engages a catch  70  mounted on another chair assembly  32  component ( FIGS. 2-3 ). The strap  50  has one end affixed to a component of the chair assembly  32  and the other end rotatably attached to the latch  54 , e.g., by passing the end of the strap  50  through a slot  56  in the latch  54  and wrapping the strap  50  around the intermediate portion  57  of the latch  54  located between the catch engaging projections  58  on the leading edge of the latch  54  and fastening the end of the strap  50  to the trailing portion of strap  50  ( FIG. 2 ). The leading edge of latch  54  is defined by two spaced catch engaging projections  58 , each comprising a flat catch engaging edge  60  to engage the catch  70 , and tabs  62  outside of and projecting beyond the flat catch engaging edge  60  to prevent side to side motion of the latch  54  once it is in place on the catch  70 . The trailing edge  69  of latch  54  opposite the two catch engaging leading edge portions  60  serves as a handle which can be used to fasten the strap latch  50  to catch  70 . 
     The catch  70 , in one preferred embodiment, comprises a back plate  72  with two projecting sides  74 , each projecting side  74  having a flat catch or fulcrum protrusion  76  and a rounded stop protrusion  78 . The fulcrum protrusion  76  is characterized by an overhanging flat edge  80  positioned such that the flat edge  80  has an angle of at least about ninety degrees (90°), and preferably an oblique angle of greater than about ninety degrees (90°), from the direction that the strap  50  will approach from, and an angled edge  82  which angles back toward the back plate  72 . The rounded stop  78  is located farther from the direction of approach of the strap  52  than the flat fulcrum protrusion  76  and does not extend as far from the back plate  72  as the fulcrum protrusion  76 . The rounded stops  78  serve as a stop for the latch  54  as it is moved from the ready position to the locked position, and prevent the latch  54  from rotating any further than just slightly over center relative to fulcrum  76  when the latch  54  is held in engagement with protrusion  76  by the tension placed on latch  54  by strap  52 . 
     To operate the strap latch  50 , the latch  54  is placed perpendicularly to the catch  70 , with the flat catch engaging edges  60  of the latch  54  against the catch  70  between the fulcrum protrusions  76  and the rounded stop protrusions  78 . ( FIG. 2 ) Then the latch  54  is rotated toward the round stop protrusions  78  such that the flat catch engaging edges  60  are in contact with the fulcrum protrusions  76 , and the latch  54  is cammed over center relative to fulcrum protrusions  76  ( FIGS. 3A ,  3 B,  3 C). The length of strap  52  is such that in this position, the latch  54  is applying a stretching force on strap  52 , which pulls the catch engaging edges  60  of latch  54  against the fulcrum protrusions  76  and the trailing edge  69  of latch  54  toward the rounded stop protrusions  78 , thereby locking latch  54  against catch  70  until someone applies a counter rotating force to rotate latch  54  back the other way. 
     In one example of a preferred embodiment, the base  90  is configured to accommodate a seat  140 , back  160  and a tablet arm  130 . ( FIG. 4 ) Base  90  includes a chair accommodating portion  92  and a tablet arm accommodating portion  94 . Base  90  has three horizontally oriented base members  96  extending from the front to the back of the base  90 , one at the outside edge of the chair accommodating portion  92 , one dividing the chair accommodating portion  92  and the tablet arm accommodating portion  94 , and one at the outside edge of the tablet arm accommodating portion  94 . The horizontal base member  96  dividing the chair accommodating portion  92  and the tablet arm accommodating portion  94  may be wider than the other horizontal base members  96 , to accommodate the width of the tablet arm  130  and the seat support  140 , with the additional width extending into the chair accommodating portion of the base  92 . Each horizontal base member  96  may optionally be fitted with a foot  98  near its front edge and back edge so that the base  90  is lifted off of the ground. (If the seating assembly  32  was not intended to include an arm, the base may utilize only two horizontal base members  96 , as the horizontal base member to support the outer edge of the tablet arm  130  would be unnecessary.) 
     To define the chair accommodating portion  92  and the tablet arm accommodating portion  94 , and to provide a basis for the installation of these items, a base frame  100  is provided on top of the horizontal base members  96 . The base frame  100  includes three members  102  ( 102 ,  102 ′,  102 ″) extending from front-to-back (one over each horizontal base member  96 ) and two base frame members  104  ( 104 ,  104 ′) extending side-to-side across the chair assembly  32 , one at the back, and one at the front. At intervals along the length of the base frame members  102 ,  104 , downwardly extending fingers  106  may be provided, which extend through corresponding holes  108  in the horizontal base member  96  to form mortise and tenon joints between the horizontal base members  96  and the base frame members  102 ,  104 . The base frame members  102 ,  104  each have complimentary slots  110  cut approximately halfway through their depth so that, where they intersect, the members  102 ,  104  interlock to form a cross lap joint. A catch  70  is secured to frame member  102 ″ for receiving the latch  54  of a strap latch  50  secured to tablet arm  130 . Another catch  70  is secured to back frame member  104 ′, in the center of the chair supporting portion of base  90 . This facilitates securing back  160  in place. Additional base frame members  102 ,  104  could be provided. For example, additional side-to-side base frame members  104  could be provided between the front and rear base frame members  104  to add stability to the base frame  100 . 
     The horizontal base members  96  may also be provided with interior corner tabs  112 , extending inwardly to the chair accommodating portion  92  and the tablet accommodating portion  94  of the base frame  100  at each interior corner. Downwardly-extending tab engaging members  114  may then be provided on the base frame members  102 ,  104 , to engage the tabs  112  and further stabilize the base frame  100  on the horizontal base members  96 . 
     In the chair accommodating portion  92 , the top edge of the side-to-side base frame members  104  have notches  116  therein at each of the four corners where the seat  140  will be attached, with the edge  118  between the notches  116  being raised. The bottom edge of the forward side-to-side base frame member  104  may also be provided with one or more seat receiving slots  120 , for example, two slots  120 , one at each side of the chair accommodating portion  92 . 
     A tablet arm  130 , with a flat area on top which can be covered to create a writing surface may be included in the chair assembly  32 . ( FIGS. 5 ,  6 ) The bottom of the tablet arm  130  is configured to fit over the outside of the tablet arm receiving portion  94  of base  90 , with the tablet arm  130  having slots  132  along the bottom interior edge, corresponding with the side-to-side base frame members  104  so that the bottom of the tablet arm  130  rests on the horizontal base members  96 , with the side-to-side base frame members  104  passing through the slots  132 . The bottom of the tablet arm  130  may also include one or more interlocking projections  134  which extend perpendicularly from the tablet arm  130 , adjacent to one or more of the side-to-side base frame members  104 . The sides of the tablet arm  130  may be enclosed with solid walls  136 , if desired. 
     The interior side of the wall  136  of the tablet arm  130  may be provided with an H-shaped brace comprising a horizontal platform  138 , and two vertically extending legs  139 . The brace may also be an upside down U-shaped brace with a horizontal platform  138  and two downwardly extending vertical legs  139 . When arm  130  is assembled to base  90 , legs  139  rest on top of the front-to-back base frame member  102 ″ thereby supporting the horizontal platform  138 . ( FIGS. 6 ,  8 ) 
     The tablet arm  130  is installed by placing the tablet arm  130  over the tablet arm accommodating portion  94  of the base  90 , so that the base frame members  104  and  104 ′ are positioned within the corresponding slots  132  on the tablet arm  130 . The interlocking projection  134  extends along the side-to-side base frame member  104 , and the brace  138 ,  139  is positioned directly on top of the front-to-back base frame member  102 ″. Then, the latch  54  of a strap latch  50 , comprising a strap  52  which is securely fastened to brace top platform  138  at one end, and having a latch  54  attached to the free end, is engaged into fixed catch  70  on frame member  102 ″. This secures the tablet arm  130  to the base  90 . The catch  70  is securely attached to the middle front-to-back base frame member  102 ″ directly below the H-shaped brace  138 ,  139  facing in toward the center of the tablet arm  130 . The strap  52  may be attached to the top of the brace  138  using any method known in the art, and the catch  70  may be fastened to the base frame member  102  using any method known in the art, including staples, nails, screws, bolts, adhesives, tape, or any other known method of fastening. The latch  54  is placed in the ready position adjacent to the catch  70 , as described above, and is then rotated into the locked position, such that the strap  52  is pulled taut, holding the tablet arm  130  securely to the base  90  ( FIGS. 8 ,  9 ). 
     A seat  140 , preferably having a fixed forward frame member  142 , a fixed rear frame member  144 , side rails  146 , a floating rear frame member  148 , seat webbing  150  and preferably at least two straps  152  affixing the floating frame member  148  to the fixed rear frame member  144 . ( FIGS. 10 ,  11 ) The fixed forward frame member  142  has at least one rearwardly projecting tab  154 , which corresponds with the seat support receiving slot  120  in the forward side-to-side base frame member  104 . The side rails  146  are attached to the fixed forward frame member  142  and are configured to rest on top of the base frame  100 . At the rear of the seat support  140 , the side rails  146  each have a pair of upwardly extending tapered members  156 , defining a slot  158  therebetween for the fixed rear frame member  144  to be inserted. The side rails  146  may also be provided with a notch  160  on the bottom edge, which may be generally in line with the tapered members  156 , to correspond with the rear side-to-side base frame member  104 ′ and assist to hold the seat support  140  in place over the base  90 . The seat webbing  150  is fixedly attached to the fixed forward frame member  142  and the floating rear frame member  148 , using any method known in the art for such attachment, including staples, nails, screws, adhesives, tapes, or any other known or equivalent method. 
     To install the seat  140 , it is placed over the chair accommodating portion of the base  92  by inserting the rearwardly projecting tabs  154  into the seat support receiving slots  120  on the forward side-to-side base frame member  104 , sliding seat  140  rearwardly, and then lowering the back portion of the seat support  140 , so that the notch  160  rests on the top edge of the rear side-to-side base frame member  104 , preventing movement of the seat support  140  in the front-to-back direction and the side rails  146  rest in notches  116  on top of the base frame members  104 . ( FIGS. 12 ,  13 ) When placed in position, the raised edges  118  engage with the interior of the side rails  146 , thereby preventing lateral movement of the seat support  140  once it is placed in position. Side rail  146  of seat  140  is also then positioned over interlocking projection  134  of tablet arm  130 , such that tablet arm  130  is additionally secured to base  90  by this interlocking relationship with seat  140 . 
     As described above, when the seat webbing  150  is attached along its back edge to the floating rear frame member  148 , when no downward force is applied to the seat of the chair assembly  32 , the floating rear frame member  148  is generally in the same plane as the fixed forward and rear frame members  142 ,  144 , such that the seat of the chair assembly  32  appears to be generally horizontal. ( FIG. 14 ) However, the seat webbing  150  and the straps  152  have sufficient stretch, such that when a downward force is applied to the seat of the chair assembly  32  the floating rear frame member  148  is permitted to move downward, such that the chair assembly  32 , when occupied has a rearwardly inclined seat which is more comfortable for the occupant than a horizontal seat. ( FIG. 15 ) 
     After seat  140  is installed on the base  90 , a back  160  may be installed. The back  160  comprises a pair of tapered side members  162 , a bottom cross member  164 , cross braces  166 , and back webbing  168 . ( FIGS. 16-17 ,  19 ) The tapered side members  162  are spaced to fit around the outside of the seat side rails  146 , and extend upward the height of back  160 . The front edge of the tapered side members  162  may also be shaped to provide ergonomic support, such as by having a curved lumbar support region  170 . The bottom cross member  164 , extends across the rear bottom edge of the tapered side members  162 . The cross braces  166  extend between the tapered side members  162 , and are spaced and oriented so as to correspond to the upwardly extending tapered members  156  of the side rails  146 , so that one cross brace  166  is on top of and in front of the upwardly extending tapered members  156  and the other cross brace  166  is on top of and behind the upwardly extending tapered members  156 . A connecting brace  172  may also be placed between the cross braces  166 , with a slit through the middle of the connecting brace  172  to permit attachment of the strap  52  on one of the cross braces  166 , and then allow the strap  52  to go downward to interact with a catch  70  through the slit in the connecting brace  172 . 
     To install, back  160  is placed into position over the seat  140 , such that the cross braces  166  align with the corresponding upwardly extending tapered members  156 . ( FIG. 17 ) Back  160  is lowered, such that the cross braces  166  are adjacent to the upwardly extending tapered members  156 , in the front and back thereof, limiting any front-to-back movement of the seat back  160 , and due to the angle of the cross braces  166 , also limiting the downward movement of the seat back  160 . The bottom cross member  164  rests outside the rear of the base frame  100 , preventing forward motion or backward rotation of the seat back  160 . 
     A strap latch  50  extends downwardly from back cross brace  166 , or optionally from the connecting brace  172 , between the floating rear frame member  148  and the fixed rear frame member  144 , to interact with a catch  70  placed on the interior wall of the rear side-to-side base frame member  104 ′. The strap latch  50  is fastened as described above to secure the seat back  160  to the base frame member  104 ′, sandwiching the seat  140  between the base frame member  104 ′ and back  160 . ( FIG. 18 ) 
     Preferably before the components of the chair assembly  32  are thus assembled, chair assembly  32  can be quickly and easily upholstered to provide a cushioned chair assembly  32 ′. ( FIG. 19 ) An upholstered envelope  201  incorporating a back cushion  202  is slipped over back  160  and secured using hook and loop fasteners or the like. Similarly, an upholstery envelope  205  including a seat cushion  206  is slipped over seat  140  to finish it. Finally, an upholstery envelope is slipped over tablet arm  130 . The upholstered components are then assembled without tools, as described above. 
     When the upholstery on the chair needs to be replaced, the components can be similarly separated for ease of removal of the old worn upholstery, and replaced with new upholstery envelopes, as discussed above. The newly upholstered components can then be reassembled in the manner discussed above. 
     Chairs  32  can be ganged together using a strap latch  50 . To facilitate this, an additional strap latch  50  is provided on the interior side of the base frame member  102  of a first chair  32  that would be adjacent to a second chair  32 ′ to form a grouped seating arrangement  30 . ( FIG. 20 ) The strap  52  is positioned to wrap underneath the horizontal base frame member  96  of the first chair assembly  32 , under the horizontal base frame member  96  of the second chair assembly  32 ′, and then up to a catch  70  provided on the interior of the base frame member of the second chair assembly  32 ′. A catch  70  may also be provided on the first chair assembly  32  where the strap  52  is fastened. The strap  52  and latch  54  can then be rolled up and secured to the catch  70  for storage when the first chair assembly  32  is not ganged to a second chair assembly  32 ′. 
     The chair and seating arrangements described herein may contain different components, for example, the tablet arm could be replaced by a regular arm, an arm with a different functionality, or be left off entirely; the seat could be replaced by a double- or triple-wide seat; the seat back could be configured in various manners or left off, and other configurations for each individual component are possible, and multiple components can be joined to form various seating arrangements. 
     Additionally, especially with reference to the system of notches, slots, tabs and other features to interlock the frames, it is understood that various arrangements of interlocking components may be provided that are within the scope of this invention, and descriptions of particular shapes or interactions between the components should not be considered limiting. Of course it is understood that the above is a description of the preferred embodiments, and that various changes and alterations can be made without departing from the spirit and broader aspects of the invention.

Technology Classification (CPC): 0