Patent Publication Number: US-6217120-B1

Title: Article of seating furniture

Description:
This invention relates to articles of seating furniture, such as chairs, love seats, and sofas, and more particularly to such furniture used in institutional environments. 
     Institutional seating, such as library chairs and sofas, advantageously have two characteristics in addition to comfort, namely, cost efficiency and the ability to withstand the rigors of use by the public. Furniture made of wood or metal is durable, but relatively expensive. In order to reduce the cost of seating furniture, it is desirable to employ a pressed composition wood product. Such products, sometimes called particleboard and fiberboard, comprise wood particles or wood fibers combined with a binder and subjected to extremely high pressure which bonds the mixture into a rigid board or panel. Such a composition product has adequate strength for utilization in making furniture. However, they lack one characteristic of natural wood, namely, resilience. 
     When furniture of the type to which the present invention relates is assembled, the parts are usually joined by suitable fasteners, such as screws or bolts. In use, the attachment points defined by the fasteners are subjected to large stresses when library patrons, or other users of institutional furniture, drop into the seats, sit on the arms of the furniture, or lean on the backs. When the furniture is made of natural wood, these stresses of the metal fastening hardware against the wood are absorbed by the wood and due to its natural resilience, the wood has the ability to bounce back and thereby accommodate rigorous use over a long period of time. 
     However, pressed composition wood products are relatively brittle, and thus do not have the ability of natural wood to absorb and rebound from stresses. Instead, such products tend to wear, even crumble, at the points where parts are fastened together. For example, bolt heads even when surrounded by individual washers tend to dig into the surface of the pressed composition products thereby chewing into the surface and, over time, wearing it away. As a consequence, the fastened joints soon become loose and the chair becomes wobbly. 
     It is an object of the present invention to overcome this problem by providing an article of seating furniture made in part of a pressed composition wood product, for the sake of cost efficiency, while at the same time employing a fastening arrangement able to perform in an institutional environment, over a long period of time, without loosening and thereby compromising the rigidity of the furniture. 
    
    
     Additional features and objects of the invention will be apparent from the following description, in which reference is made to the accompanying drawings. 
     In the drawings: 
     FIG. 1 is a perspective view from the top, front, and right side of a chair according to the present invention; 
     FIG. 2 is a perspective view of the chair from the bottom front and right side; 
     FIG. 3 is a perspective view of the chair from the bottom rear, and left side; 
     FIG. 4 is a cross-sectional taken along line  4 — 4  of FIG. 1; 
     FIG. 5 is a fragmentary view, on an enlarged scale, of a hardware connection shown in FIG. 2; and 
     FIG. 6 is an fragmentary exploded view, on an enlarged scale, of an assembled joint of the chair. 
    
    
     The chair chosen to illustrate the present invention, and shown in FIGS. 1-4, includes two side panels  10  and  11  substantially parallel to each other and arranged in space-apart generally vertical planes. Each of the panels is formed of a pressed composition wood product, such as particleboard or fiberboard. These composition products comprise wood particles or wood fibers mixed with a binder and then highly compressed to produce a flat board. Another possible pressed composition wood product which might be used is chipboard, which is similar to particleboard and fiberboard, except that it is made using larger wood chips. Because chipboard is usually not as strong as particle board or fiberboard, the two former products are preferred for the purposes of the present invention. 
     Extending between the panels  10  and  11  are three horizontal and parallel connector strips, or stretchers,  12 ,  13 , and  14 . The connector strips serve to maintain side panels  10  and  11  in upright condition, and also serve to support the chair seat and back as will be described in more detail below. 
     Each end of each connector strip is secured to its respective side panel by a hardware arrangement, best seen in FIGS. 2,  5 , and  6 . Since all six securements of the ends of connector strips  12 ,  13 , and  14  to the side panels  10  and  11  are identical, only one will be described, namely, the securement of one end of connector strip  13  to side panel  11 . 
     The hardware, all of which may be made of metal, includes an outer, generally rectangular, plate  17 , and an inner rectangular plate  18 , the latter forming one wing of an angle  19 , the angle having another wing  20 . Plates  17  and  18  sandwich between them side panel  11 . Plate  17  is provided with three holes  23 , plate  18  is formed with three holes  24 , and side panel  11  is formed with three holes  25 . The three holes in each of the plates and the panel are arrayed in a triangular pattern, and each hole  23  in plate  17  is aligned with one of the holes  24  in plate  18  and one of the holes  25  in panel  11 . 
     Three threaded bolts  26 , each surrounded by a washer  27 , pass through the series of aligned holes  23 ,  24 , and  25 , from the inner face of plate  18  to and beyond the outer face of plate  17 . Internally threaded tubular nuts  28  are threaded on to the bolts  26  and tightened, so that side panel  11  is firmly sandwiched between plates  17  and  18 . 
     Wing  20  of angle  19  is formed with three holes  31  in a triangular pattern which register with three starter holes  32  formed near the end of connector strip  13 . By means of three wood screws  33 , wing  20  of angle  19  is firmly fastened to connector strip  13 , thereby securing the end of connector strip  13  to side panel  11 . 
     The chair seat and back may be fabricated of a generally L-shaped piece of plywood  36  (FIGS. 3 and 4) to which an upholstered seat  37  and upholstered back  38  are secured. The seat portion of plywood  36  rest upon connector strips  12  and  13 , and the back portion of plywood  36  rests against connector strip  14 . The width of plywood  36 , as well as seat  37  and back  38 , is about equal to the spacing between side panels  10  and  11 . To hold the unitary seat and back in place, it is desirable to employ two angles  39 , one wing of each angle  39  being secured to the inner face of one of the side panels  10 ,  11 , and the other wing of each angel  39  being secured to the bottom of the seat portion of plywood  36 . 
     The lower edge of each side panel  10 ,  11  is preferable provided with a pair of metal or plastic discs  42 , serving as feet for the chair. Along its upper edge, each side panel  10 ,  11  may have fixed to it a finishing strip of wood or plastic serving as an arm rest  43 . 
     The example of the invention described above is a single-occupancy chair. However the article of furniture of the present invention could be of about double that length, to provide a love seat, or even longer to form a sofa. In the case of a longer piece, an intermediate panel, or panels, may be employed in addition to the side panels  10  and  11 . In such a case, connector strips  12 - 14  extend between each two successive panels and are secured to those panels as described above. 
     The hardware securing arrangement between side panels and connecting strips described above has been found to remain tight despite subjecting the furniture to rigorous testing, so that the seat retains its rigid structure and avoids becoming shaky or wobbly. It is believed that this beneficial effect results in part from the use of enlarged plates  17  and  18 , each of which accommodates a plurality of fasteners  26 ,  28 . The large plates resist the tendency of the bolt heads and nuts to dig into the surfaces of panels  10  and  11 . Also, the triangular pattern of the fasteners appears to add strength, possibly due to exhibiting a “truss” effect, which tends to resist lateral motion of the fasteners during use. 
     The invention has been shown and described in preferred form only, and by way of example, and many variations may be made in the invention which will still be comprised within its spirit. It is understood, therefore, that the invention is not limited to any specific form or embodiment except insofar as such limitations are included in the appended claims.