Patent Publication Number: US-8540315-B2

Title: Nestable chair with seat rotation and stop arrangement

Description:
FIELD OF THE INVENTION 
     The present disclosure generally relates to a chair, and more particularly, pertains to a chair configured to provide for a horizontal nesting arrangement. 
     BACKGROUND OF THE INVENTION 
     It is known to provide a nestable chair or system of nestable chairs, in which, for purposes of compact storage, one chair is received within another chair. Arrangement for vertically nestable or “stacking” chairs where one chair is fitted atop another chair to form a vertical stack of chairs are well known. Typically, such vertically nestable chairs will include a backrest and a generally orthogonal base (i.e. a box-shaped base consisting of at least two and typically four leg supports) which is configured so that one chair can be fitted onto another chair in a compact arrangement, with the base of the upper chair fitting over the seat of the lower chair. 
     Arrangements for horizontally nestable chairs, where one chair is fitted into another chair to form a horizontal line of chairs, are also known. Such horizontally nestable chairs typically also include a base formed by four leg supports. Horizontally nestable chairs are known to provide a rotation or flip mechanism for enabling pivotal movement of the seat relative to the backrest between an initial seating position and an upwardly rotated nesting position. In addition, one or more stops are included on the chair for supporting the seat in the seating position. 
     It remains desirable to provide a horizontally nestable chair that provides for relatively compact storage with an improved seat rotation and stop arrangement. 
     SUMMARY OF THE INVENTION 
     The present disclosure relates to a nesting chair including a base having a transverse member. A backrest and a seat are interconnected with the base. A seat rotation mechanism is disposed between the base and the seat, and is configured to allow the seat to rotate from an initial seating position to an upwardly rotated nesting position. The seat rotation mechanism includes a first bearing area defined by an underside of the seat, and a second bearing area defined by a separate bearing member. The first and second bearing areas are located on opposite sides of the transverse member. A retainer arrangement is interconnected with the bearing member and the seat to secure the bearing member to the seat with the transverse member therebetween. The seat is rotatable about the transverse member from the generally horizontal seating position to the upwardly rotated nesting position to enable the nesting chair to be nested with a plurality of like chairs. The transverse member is provided with a stop engageable with the seat for maintaining the seat in the seating position. 
     In one embodiment, the stop is defined by a U-shaped tube fixed to and extending forwardly of the transverse member. The base includes a set of legs extending downwardly from the transverse member. The base also includes backrest supports for supporting the backrest therefrom. The seat includes an upper portion and a lower portion with a set of reinforcing plates interposed between the upper and lower portions. The underside of the seat includes a bearing saddle defining a first concave bearing surface extending longitudinally of the bearing saddle. The bearing member defines a second concave bearing surface extending longitudinally of the bearing member. The first and second bearing surfaces are engageable with an outer surface of the transverse member. The first and second bearing surfaces include bearing collar segments engageable with the outer surface of the transverse member. The bearing collar segments and the transverse member receive a roll pin for maintaining a centering position of the seat relative to the transverse member. The retainer arrangement preferably includes a set of fasteners having end portions secured to the reinforcing plates positioned between the upper and lower portions of the seat. The stop is engageable with the underside of the seat forwardly of the first and second bearing areas. The first and second bearing areas are engageable with the transverse member along substantially the entire length thereof. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The best mode of carrying out the disclosure is described herein below with reference to the following drawing figures. 
         FIG. 1  is a perspective view of a nesting chair having a seat rotation and stop arrangement in accordance with the present disclosure; 
         FIG. 2  is an exploded view of the nesting chair show in  FIG. 1 ; 
         FIG. 3  is an enlarged, exploded, detailed view of a bottom portion of a seat employed in the nesting chair of  FIG. 1 ; 
         FIG. 4  is a side view of the nesting chair shown in  FIG. 1  in a seating position; 
         FIG. 5  is a view similar to  FIG. 4  showing the nesting chair in an upwardly rotated nesting position; 
         FIG. 6  is a top view of  FIG. 5 ; 
         FIG. 7  is an enlarged fragmentary sectional view showing the seat rotating mechanism; 
         FIG. 8  is an enlarged fragmentary sectional view of the nesting chair in the nesting position shown in  FIG. 5 ; and 
         FIG. 9  is an enlarged fragmentary sectional view of the nesting chair in the seating position shown in  FIG. 4 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings,  FIGS. 1-9  illustrate a nestable chair  10  having a seat rotation and stop arrangement in accordance with the present disclosure. The chair  10  is generally comprised of a base  12 , a backrest  14 , a cantilevered seat  16 , and a seat rotation mechanism  18  for pivotally moving the seat  16  from a generally horizontal seating position to a generally upright storage position. When in the storage position, a number of like chairs  10  may be conveniently nested together for storage. 
     Referring initially to  FIGS. 1 and 2 , the base  12  provides a support structure for the chair  10 , and generally includes a single crossmember  20  preferably in the form of a horizontally and linearly extending or transverse straight tube. The transverse tube  20  has a medial portion  20   a  and a pair of spaced outer ends  20   b . The crossmember  20  is interconnected, such as by welding, to a set of legs  22  extending downwardly from the tube  20  for supporting the chair  10  on a floor or other support surface. The legs  22  are typically formed by a pair of forwardly extending tubular leg members  24 , and a pair of rearwardly extending tubular leg members  26 . Each pair of leg members  24 ,  26  has upper end portions  28  that extend inwardly of opposite ends of the tube  20 , and are fixed to the bottom of the tube  20  adjacent each other. The upper end portions  28  have open ends that are closed such as by plugs  30  that are frictionally retained by inner walls of the upper end portions  28 . Each pair of leg members  24 ,  26  has lower end portions  32  with open ends that extend downwardly and receive bushings  34  and caster wheels  36  configured to swivel and provide movement of the chair  10  on the floor. Although not illustrated, the disclosure contemplates that other leg arrangements may be interconnected to the tube  20 . 
     In the example shown in the drawings, the tube  20  additionally provides support for a pair of upwardly extending arm rest supports  38  configured to receive and secure a pair of arm rests  40  on corresponding arm rest brackets  42  using fasteners  44 . Arm rest supports  38  may be integrally formed with the tube  20 , or may be separate members that are received and secured within open ends of the tube  20  to support the arm rest  40 . 
     A pair of curved tubular backrest supports  46  is mounted on the base  12  for supporting the backrest  14  therefrom. The backrest supports  46  have open lower end portions  48  that are welded or similarly affixed to rear surfaces of the opposite ends of the tube  20  with the open lower end portions  48  being closed such as by plugs  50 . The backrest supports  46  have open upper end portions  52  that hold elongated receivers  54 , coil springs  56  and bushings  58  adapted to retain backrest support springs  60  configured to be received within elongated passages formed within the backrest  14 . Accordingly, the backrest  14  is designed to be relatively flexible such that it may flex or tilt rearwardly with respect to base  12 . In addition, a set of horizontal slots  62  extend across a portion of the backrest  14  to provide the backrest  14  with increased flexibility. The backrest  14  is typically constructed out of a plastic such as, for example, polypropylene or similar such materials, and may be additionally upholstered, if desired. 
     The base  12  further provides a seat stop  64  for supporting the seat  16  in the operative or down seating position. In the embodiment shown, the seat stop  64  takes the form of a U-shaped tube which is welded or otherwise affixed to the crossmember  20 , and extends forwardly and slightly upwardly therefrom between the forwardly extending legs members  24 . The U-shaped tube  64  has outer legs  64   a  fixed to the outer ends  20   b  of the transverse member  20 , and a bridge section  64   b  connecting the legs  64   a  and extending substantially parallel to the medial portion  20   a  of the transverse member  20 . It should be understood that the seat stop  64  may alternatively be formed from more than one member fixed to the tube  20 . 
     Referring to  FIGS. 7-9 , the seat rotation mechanism  18  is configured to allow the seat  16  to be manually rotated or flipped from the operative or down seating position shown in  FIGS. 1 ,  4  and  9  to the generally vertical storage position shown in  FIGS. 5 ,  6  and  8  in which position a group of like chairs may be horizontally nested together. The crossmember or horizontal tube  20  serves as the surface about which seat rotation mechanism  18  rotates the seat  16  of the chair  10  as will be described in further detail below. 
     The seat  16  includes an upper portion  66 , a lower portion or shroud  68 , and a liner  70  interposed between the upper and lower portions  66 ,  68 . If desired, the liner  70  may be upholstered with foam and fabric. As seen in  FIGS. 2 and 9 , a pair of reinforcing plates  72  are trapped between the shroud  68  and liner  70  which are held together by a plurality of clips  74 . The shroud  68  and the retaining plates  72  provide the structural support for the seat rotation mechanism  18  as the seat  16  rotates about the tube  20 . 
     Referring now to  FIG. 3 , the underside of shroud  68  is integrally constructed with a bearing saddle  76  formed with an elongated concave recess  78  defining a first semi-cylindrical bearing surface. The saddle  76  also includes a first bearing collar segment  80  formed with a semi-cylindrical configuration and located in the center of the first bearing surface  78 . The saddle  76  is further configured with a pair of extensions  82  on opposite ends thereof, and a set of apertures  84  provided on opposite sides of the first bearing surface  78 . A bearing cap  86  is constructed with an elongated concave recess  88  defining a second semi-cylindrical bearing surface complimentary to the first bearing surface  78 . The bearing cap  86  also includes a second semi-cylindrical bearing collar segment  90  adapted to mate with the first bearing collar segment  80  and is positioned centrally of the second bearing surface  88 . The bearing cap  86  is formed with a number of openings  92  alignable with the apertures  84  in the bearing saddle  76 . The bearing cap  86  is designed to be mated against the saddle  76  with the crossmember or tube  20  interposed therebetween such that the bearing surfaces  78 ,  88  and the bearing collar segments  80 ,  90  are engaged for relative rotation with respect to the outer cylindrical surface of the tube  20  as seen in  FIGS. 7 ,  8  and  9 . The bearing collar segments  80 ,  90  are formed internally with mating slots  80   a ,  90   a , respectively, defined by walls that surround and enclose the outer surfaces of transverse member  20 . The bearing cap  86  is fastened to the saddle  76  by passing a series of bolts  94  through washers  96 , openings  92 , and apertures  84 , and securing threaded ends of the bolts  94  in threaded holes  98  formed in the end portions of the retaining plates  72  as seen in  FIGS. 2 ,  8  and  9 . A roll pin  100  ( FIG. 7  extends through aligned recesses  102  formed in an outer wall of the medial portion  20   a  of crossmember  20  and has end portions  100   a  projecting into the slots  80   a ,  90   a  of the mating bearing collar segments  80 ,  90  and engaging side walls of the slots  80   a ,  90   a  to maintain the position of the seat  16  on center so that there is no lateral movement of the seat  16 . By this arrangement, the transverse member  20  and the roll pin  100  are circumferentially surrounded within the bearing saddle  76  on seat  16  and the bearing cap  86 . Bearing covers  104  are provided over the saddle extensions  82  and around outer ends of the crossmember  20  and the seat stop  64  as best seen in  FIGS. 1 and 6 . 
     With this construction, the seat  16  rotates about the crossmember  20  between the down position (useful as a seat) shown in  FIGS. 1 ,  4  and  9 , and the up position shown in  FIGS. 5 ,  6  and  8  (allowing nesting of chairs). It should be appreciated that the first and second bearing surfaces  78 ,  88  define a large bearing area extending substantially the entire length of the medial portion  20   a  of crossmember  20  as the seat  16  rotates about the tube  20 . In addition, the reinforcing plates  72  further enable bearing support for the seat rotation mechanism  18 . In the down position, the seat  16  is effectively stopped from rotation by the seat stop  64  welded to the crossmember  20 . In the up position, rotation of the seat  16  is stopped by the contact of the seat  16  with the backrest  14 . Slots  80   a ,  90   a  are continuous so that the bearing elements  76 ,  86  can rotate freely between the up and down stop positions of the seat  16  defined by the back rest  14  and the stop  64 . 
     Accordingly, the seat rotation and stop arrangement of the chair  10  provides a relatively simple and cost effective method for enabling nesting a number of chairs, and conveniently providing a solid structural element on which the cantilevered load of the seat  16  bears when the chair is in the seating position. 
     While the invention has been described with reference to a preferred embodiment, those skilled in the art will appreciate that certain substitutions, alterations and omissions may be made without departing from the spirit thereof. Accordingly, the foregoing description is meant to be exemplary only and should not be deemed limitative on the scope of the invention set forth with the following claims.