Abstract:
The present disclosure relates to a foldable chair having an expanded use configuration and a collapsed storage configuration. The foldable chair includes front and rear legs, a seat back coupled to the front legs, and a seat bottom mounted to pivot relative to the front and back legs.

Description:
This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application Ser. No. 60/823,227, filed Aug. 22, 2006, which is expressly incorporated by reference herein. 

   BACKGROUND 
   The present disclosure relates to a foldable chair, and particularly to a foldable chair that has an expanded use configuration and a collapsed storage configuration. More particularly, the present disclosure relates to a foldable chair including front and rear legs, a seat back coupled to the front legs, and a seat mounted to pivot relative to the front and back legs. 
   SUMMARY 
   A foldable chair in accordance with the present disclosure includes a right-side frame, a foldable left-side frame, and a seat or seat bottom positioned to lie between the foldable right-side and left-side frames. Fold-control linkages or spacing-control means or linking means are provided to couple the front and rear legs to each other and to couple the seat to each of the right-side and left-side frames to allow movement of the legs relative to each other and movement of the seat relative to the frames between a generally horizontal extended position upon unfolding of the foldable chair to assume an expanded, use position and a generally vertical retracted position upon folding of the foldable chair to assume a collapsed, storage position. 
   In illustrative embodiments, the linking means are configured to establish at least a minimum leg clearance space between front and rear legs included in each of the right-side and left-side frames upon folding of the foldable chair to assume the collapsed, storage position. The spacing-control means are configured to maintain at least a minimum seat clearance space between the seat and each of the right-side and left-side frames during folding and unfolding of the foldable chair. In illustrative embodiments, each of the minimum seat and leg clearance spaces is greater than outer diameters or other similar external dimensions of the front and rear legs included in the right-side and left-side frames. 
   Additional features of the present disclosure will become apparent to those skilled in the art upon consideration of the following detailed description of illustrative embodiments exemplifying the best mode of carrying out the disclosure as presently perceived. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The detailed description particularly refers to the accompanying figures in which: 
       FIG. 1  is a first perspective view of a foldable chair in accordance with the present disclosure showing the chair in an expanded, use position and showing (in the foreground) one of the extensible rear legs included in the foldable chair; 
       FIG. 2  is another perspective view of the foldable chair of  FIG. 1  showing a seat back coupled to upper ends of the front legs and a seat supported between a right-side frame comprising companion front and rear legs and a left-side frame comprising companion front and rear legs; 
       FIG. 3  is a sectional view taken along line  3 - 3  of  FIG. 1 , showing “seat” clearance space provided between the seat and the right-side frame and also between the seat and the left-side frame when the foldable chair is unfolded to assume an expanded use position; 
       FIGS. 4-6  show a folding sequence as the foldable chair of  FIGS. 1 and 2  is folded to assume a collapsed, storage position shown in  FIGS. 6 and 7 ; 
       FIG. 4  is an enlarged side elevation view of the foldable chair of  FIGS. 1 and 2  during folding movement of the seat in a “clockwise” direction during controlled collapse of the foldable chair and showing telescoping movement of an upper rear leg “rod” section relative to a companion lower leg “sleeve” section to lengthen the extensible rear leg to assume a “longer” second length; 
       FIG. 5  is a side elevation view similar to  FIG. 3  showing continued folding movement of the seat in the clockwise direction and showing further lengthening of the extensible rear leg to assume an even longer third length; 
       FIG. 6  is a side elevation view similar to  FIGS. 3 and 4  showing still more folding movement of the seat in the clockwise direction to cause the foldable chair to reach the collapsed, storage position and showing further lengthening of the extensible rear leg to assume a still longer fourth length and showing “leg” clearance spaces between the front legs included in the right-side and left-side frames and the rear legs included in the right-side and left-side frames; 
       FIG. 7  is a side elevation similar to  FIG. 6  but showing a “left” side of the collapsed chair rather than a “right” side of the collapsed chair as shown in  FIG. 6 ; and 
       FIG. 8  is a front elevation view of the foldable chair of  FIGS. 1-7  in the collapsed, storage position of  FIGS. 6 and 7  showing “seat” clearance spaces provided between the seat and the front and rear legs included in the right-side frame and also between the seat and the front and rear legs included in the left-side frame. 
   

   DETAILED DESCRIPTION 
   A foldable chair  10  in accordance with the present disclosure includes a seat  12 , a seat back  14 , a right-side frame  16 , and a left-side frame  18  as shown, for example, in  FIGS. 1 and 2 . Right-side frame  16  includes front and rear legs  161 ,  162  as shown, for example, in  FIGS. 1 and 2 . Left-side frame  18  includes front and rear legs  181 ,  182  as shown, for example, in  FIGS. 1 and 2 . Foldable chair  10  is configured to provide relatively wide clearance spaces between: (1) seat  12  and each of right-side and left-side frames  16 ,  18 ; (2) front and rear legs  161 ,  162 ; and (3) front and rear legs  181 ,  182  during folding and unfolding of foldable chair  10  as suggested in  FIGS. 3-8 . 
   As suggested in  FIGS. 2 ,  3 ,  6 , and  8 , an illustrative first seat support or spacing-control means  21  is provided for coupling seat  12  to right-side frame  16  so that seat  12  is supported for movement between a generally horizontal extended orientation when foldable chair  10  is “opened” to assume an expanded use position as shown in  FIG. 1  and a generally vertical retracted orientation when foldable chair is “closed” to assume a collapsed, storage position as shown in  FIGS. 6 ,  7 , and  8 . An illustrative second seat support or spacing-control means  22  is provided for coupling seat  12  to left-side frame  18  so that seat  12  is supported for movement from the extended orientation shown in  FIG. 1  to the retracted orientation shown in  FIGS. 7 and 8 . First and second seat support means  21 ,  22  are configured to maintain at least a predetermined “seat” clearance space  1216  between seat  12  and right-side frame  16  as shown, for example, in  FIG. 3  and at least a predetermined seat clearance space  1218  between seat  12  and left-side frame  18  as shown, for example, in  FIG. 3 . 
   As suggested in  FIGS. 1 ,  6 , and  8 , an illustrative first rear leg support or leg mechanism or linking means  31  is associated with right-side frame  16  and provided for coupling rear leg  162  to companion front leg  161  to control movement and separation of rear leg  162  relative to front leg  162  during folding and unfolding of foldable chair  10 . First rear leg linking means  31  is configured to maintain at least a predetermined “leg” clearance space  160  between front and rear legs  161 ,  162  of right-side frame  16  upon movement of foldable chair  10  to assume a collapsed, storage position as shown, for example, in  FIG. 6 . 
   As suggested in  FIGS. 1 ,  7 , and  8 , an illustrative second rear leg support or leg mechanism or linking means  32  is associated with left-side frame  18  and provided for coupling rear leg  182  to companion front leg  181  to control movement and separation of rear leg  182  relative to front leg  181  during folding and unfolding of foldable chair  10 . Second rear leg linking means  32  is configured to maintain at least a predetermined leg clearance space  180  between front and rear legs  181 ,  182  of left-side frame  18  upon movement of foldable chair  10  to assume the collapsed, storage position as shown, for example, in  FIG. 7 . 
   Front leg  161  of right-side frame  16  is coupled to seat back  14  and arranged to extend alongside seat  12  in spaced-apart confronting relation to a right side wall  24  included in seat  12  as suggested in  FIGS. 1 and 2 . Front leg  161  is separated from seat  12  by seat clearance space  1216  in the expanded, use position, as shown, for example, in  FIG. 3  and in the collapsed, storage position a shown, for example, in  FIG. 8 . 
   In the illustrated embodiment, rear leg  162  of right-side frame  16  is an “extensible” leg that includes an upper rod  33  telescopically received for “up-and-down” movement in a rod-receiver channel  134  formed in a lower sleeve  34  as suggested in  FIGS. 1 ,  3 , and  4 - 6 . Upper rod  33  is constrained to move relative to companion lower sleeve  34  from a “retracted” position shown in  FIG. 1  establishing a “short” length L 1  of rear leg  162  to an “extended” position shown in  FIG. 6  establishing a relatively longer length L 4  of rear leg  162 . Front leg  161  has an outer diameter  161 ′ that is less than leg clearance space  160  and lower sleeve  34  of rear leg  162  has an outer diameter  34 ′ that is also less than leg clearance space  160 . Rear leg  162  is separated from seat  12  by seat clearance space  1216  in the expanded, use position as shown, for example, in  FIG. 3  and in the collapsed, storage position as shown, for example, in  FIG. 8 . 
   Likewise, as suggested in  FIGS. 1 and 2 , front leg  181  of left-side frame  18  is coupled to seat back  14  and arranged to extend in spaced-apart confronting relation to a left-side wall  26  included in seat  12 . Front leg  181  is separated from seat  12  by seat clearance space  1218  in the expanded, use position as shown, for example, in  FIG. 3  and in the collapsed, storage position as shown, for example, in  FIG. 8 . 
   In the illustrated embodiment, rear leg  182  of left-side frame  18  includes an upper rod  35  telescopically received for up-and-down movement in a rod-receiver channel  136  formed in a lower sleeve  36  as suggested in  FIGS. 1 and 8 . Upper rod  35  is constrained to move relative to companion lower sleeve  36  from a retracted position shown in  FIG. 1  wherein rear leg  182  is characterized by “short” length L 1  to an extended position shown in  FIG. 7  wherein rear leg  182  is characterized by relatively longer length L 4 . Front leg  181  has an outer diameter  181 ′ that is less than leg clearance space  180  and lower sleeve  36  of rear leg  182  has an outer diameter  36 ′ that is also less than leg clearance space  180  as shown, for example, in  FIG. 7 . In an illustrative embodiment, leg clearance space  160  is about equal to leg clearance space  180 . Rear leg  182  is separated from seat  12  by seat clearance space  1218  in the expanded, use position as shown, for example, in  FIG. 3  and in the collapsed, storage position as shown, for example, in  FIG. 8 . 
   A stretcher  37  is arranged to interconnect lower sleeve  34  of rear leg  162  and lower sleeve  36  of extensible rear leg  182  as shown, for example, in  FIG. 3 . Illustrative rod-receiver channels  134  and  136  are also shown in  FIG. 3 . A top surface  28  included in seat  12  and arranged to interconnect right and left side walls  24 ,  26  of seat  12  is also shown in  FIG. 3 . 
   First seat support mechanism or spacing-control means  21  illustratively includes a first pivot axle  41  associated with front leg  161  and also includes a second pivot axle  42 , a mounting bracket  43 , and a fastener  44 , associated with rear leg  162  as illustrated, for example, in  FIGS. 2 and 3 . First pivot axle  41  is coupled to right side wall  24  of seat  12  and to front leg  161  to support seat  12  for pivotable movement relative to front leg  161  about pivot axis  411 . Mounting bracket  43  includes an inner plate  45  adjacent to right side wall  24  of seat  12 , an outer plate  46  adjacent to lower sleeve  34  of extensible rear leg  162 , and a spreader plate  47  coupled to and interconnecting inner and outer plates  45 ,  46  at essentially a right angle to each plate  45 ,  46 , as suggested in  FIG. 3 . Second pivot axle  42  is coupled to right side wall  24  of seat  12  and to inner plate  45  of mounting bracket  43  to support seat  12  for pivotable movement relative to extensible rear leg  162  about pivot axis  422 . Fastener  44  is coupled to outer plate  46  and to lower sleeve  34  to anchor outer plate  46  in a fixed, stationary position on lower sleeve  34  of extensible rear leg  162 . It is within the scope of the present disclosure to use other suitable linkages to provide and maintain seat clearance  1216  during folding and unfolding of foldable chair  10 . 
   Second seat support mechanism or spacing control means  22  illustratively includes a first pivot axle  51  associated with front leg  181  and also includes a second pivot axle  52 , a mounting bracket  53 , and a fastener  54  associated with rear leg  182  as illustrated, for example, in  FIGS. 2 and 3 . First pivot axle  51  is coupled to left side wall  26  of seat  12  and to front leg  181  to support seat  12  for pivotable movement relative to front leg  181  about pivot axis  511 . Mounting bracket  53  includes an inner plate  55  adjacent to left side wall  26  of seat  12 , an outer plate  56  adjacent to lower sleeve  36  of extensible rear leg  182 , and a spreader plate  57  coupled to and interconnecting inner and outer plates  55 ,  56  at essentially a right angle to each plate  55 ,  56 , as suggested in  FIG. 3 . Second pivot axle  52  is coupled to left side wall  26  of seat  12  and to inner plate  55  of mounting bracket  53  to support seat  12  for pivotable movement relative to extensible rear leg  182  about pivot axis  522 . Fastener  54  is coupled to outer plate  56  and to lower sleeve  36  to anchor outer plate  56  in a fixed, stationary position on lower sleeve  36  of extensible rear leg  182 . It is within the scope of the present disclosure to use other suitable linkages coupled to front and rear legs  181 ,  182  included in left-side frame  18  to provide and maintain seat clearance space  1218  during folding and unfolding of foldable chair  10 . 
   First rear leg mechanism or linking means  31  illustratively includes a support bracket  71 , a fastener  72 , and a pivot axle  73  as suggested in  FIGS. 1 and 4 . In the illustrated embodiment, support bracket  71  includes a collar  74  wrapped around front leg  161  and anchored to front leg  161  by fastener  72 . Support bracket  71  also includes an extension plate  75  appended to collar  74  and extending from front leg  161 . Pivot axle  73  is coupled to extension plate  75  and to an upper end of upper rod  33  to support rear leg  162  for pivotable movement relative to support bracket  71  about pivot axis  711  during folding and unfolding of foldable chair  10  as suggested in FIGS.  1  and  4 - 6 . Extension plate  75  remains in a constant fixed position when seat  12  is moved between the extended, use position and the collapsed, storage position. A standoff  76  included in first rear leg support means  31  is appended to, for example, lower sleeve  34  of rear leg  162  and arranged to extend toward and mate with or abut companion front leg  161  to establish leg clearance space  160  upon movement of foldable chair  10  as suggested in  FIGS. 1 ,  4 , and  5  to assume a collapsed, storage position as suggested in  FIG. 6 . It is within the scope of the present disclosure to use other suitable linkages to provide and maintain leg clearance space  160  during folding of foldable chair  10 . 
   Second rear leg support means  32  illustratively includes a support bracket  91 , a fastener  92 , and a pivot axle  93  as suggested in  FIGS. 1 and 7 . In the illustrated embodiment, support bracket  91  includes a collar  94  wrapped around front leg  181  and anchored to front leg  181  by fastener  92 . Support bracket  91  also includes an extension plate  95  appended to collar  94 . Pivot axis  93  is coupled to extension plate  95  and to an upper end of upper rod  35  to support rear leg  182  for pivotable movement relative to support bracket  71  about pivot axis  911  during folding and unfolding of foldable chair  10  as suggested in  FIGS. 1 and 7 . Extension plate  95  remains in a constant fixed position when seat  12  is moved between the extended, use position and the collapsed, storage position. A standoff  90  included in second rear leg support means  32  is appended, for example, to lower sleeve  36  of rear leg  182  and arranged to extend toward and mate with or abut companion front leg  181  to establish leg clearance space  180  upon movement of foldable chair  10  as suggested in  FIGS. 1 ,  4 , and  5  to assume a collapsed, storage position as suggested in  FIG. 7 . It is within the scope of the present disclosure to use other suitable linkages to provide and maintain leg clearance space  180  during folding of foldable chair  10 . 
   Once foldable chair  10  is unfolded to assume the expanded, use position shown, for example, in  FIGS. 1-3 , seat clearance space  1216  is provided between seat  12  and right-side frame  16  and seat clearance space  1218  is provided between seat  12  and left-side frame  18 . These seat clearance spaces  1216 ,  1218  are maintained as foldable chair is folded (in a manner shown, for example, in  FIGS. 4-6 ) to assume a collapsed, storage position as shown, for example, in  FIG. 8 . The size of seat clearance spaces  1216 ,  1218  are a function of the lengths of pivot axles  41 ,  51 , respectively and spreader plates  47 ,  57 , respectively. In addition, when foldable chair  10  is in the expanded, use position and upper rod  33  of rear leg  162  is in the shortened, retracted position, a plate clearance space  1675  exists between an end  175  of extension plate  75  and an upper end  345  of sleeve  34 , as shown in  FIG. 1 . The plate clearance space  1675  is greater than an outer diameter of legs  161 ,  162 ,  181 ,  182 . A similar plate clearance space (not shown) to space  1675  exists between an end of extension plate  95  and an upper end of sleeve  36 . This similar plate clearance space is greater than an outer diameter of legs  161 ,  162 ,  181 ,  182 . 
   As foldable chair  10  is folded in a manner shown, for example, in FIGS.  1  and  4 - 6 , extensible rear legs  162 ,  182  vary in length (owing to relative movement between upper rods  33 ,  35  and lower sleeves  34 ,  36 ) from a short length L 1  suggested in  FIG. 1 , to a longer length L 2  suggested in  FIG. 4 , to a still longer length L 3  suggested in  FIG. 5 , and to a longest length L 4  suggested in  FIGS. 6 and 7 . Once foldable chair  10  is folded to assume the collapsed, storage position shown, for example, in  FIGS. 6 and 7 , leg clearance space  160  is provided between front and rear legs  161 ,  162  of right-side frame  16  and leg clearance space  180  is provided between front and rear legs  181 ,  182  of left-side frame  18 . The size of leg clearance space  160  is a function of the effective lengths of support bracket  71  and standoff  76  while the size of leg clearance space  180  is a function of the effective lengths of support bracket  91  and standoff  96 .