Abstract:
A school desk top or table top ( 31 ) is disclosed having a buffer ( 37, 47 ) extending around its perpendicular side edge and formed by injection moulding. The front edge ( 42, 52 ) and rear edge ( 43, 53 ) of the desk have a curved buffer ( 37 ) to avoid a sharp edge on which a student&#39;s forearm might rest. However, the side edges ( 41, 54 ) have a substantially flat buffer ( 47 ) to enable two like desks ( 40, 50 ) to be edge abutted and thereby provide a substantially continuous flat working surface.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to furniture and, in particular, to furniture having a planar substrate such as the working surface of a desk. The invention is particularly applicable to school desks, however, the invention is not restricted thereto. 
       BACKGROUND ART 
       [0002]    Class room furniture, such as school desks, constitutes a very demanding segment of the overall furniture market in that such articles of furniture must be inexpensive in order to be able to be purchased in large numbers by educational institutions. Yet such furniture must be very hard wearing, particularly in terms of resisting attack of various kinds from students who have no particular love of their school furniture. 
         [0003]    It is desirable in providing a working substrate such a table top or desk top to avoid sharp edges and to provide curved surfaces wherever possible. In particular, those edges against which a user is liable to rest an arm in the course of sitting or working at the desk or table should not have a sharp edge. Thus many tables, and circular tables in particular, have a curved edge profile, which is sometimes referred to as a bull nose profile. 
         [0004]    However, a particular requirement of school desks is that the edge of the desk top which faces the torso of a student sitting at the desk (and which is conveniently referred to as the rear edge of the desk) should be curved or bevelled so as not to produce a sharp edge against which the underside of the forearms of the student can come into contact. However, in many classrooms situations it is desirable to be able to edge abut adjacent desks and thereby form a row. Thus the left and right side edges of the desk top should be substantially vertical so as to permit the edge abutment to take place without creating a valley or groove between adjacent desk top surfaces. Generally the front edge of the desk is not critical as to its profile, save that it is generally desirable for the front edge to avoid sharp edges. 
         [0005]    It is possible to create such shaped or curved edges from planar wooden substrates by means of routing, for example. However, for cost reasons the wooden substrate is normally fabricated from a “board” formed by timber particles which are glued together or formed from multiple plies of thin veneer such as 5 ply or 10 ply. Under these circumstances, routing of the edge provides a very weak surface relative to the upper (and generally also lower) surfaces which can be laminated with a plastic hardwearing veneer such as those sold under the names FORMICA or LAMINEX (Registered Trade Marks). 
         [0006]    In recent years, it has been in the practice to provide the edges of such wooden desk tops with a plastics buffer or bead which extends around the edge and substantially strengthens the edge against damage, particularly chipping or splitting of the edge. Such plastic buffers have been secured to the edges of the desk top by means of a friction fit or by means of gluing. 
       GENESIS OF THE INVENTION 
       [0007]    The genesis of the present invention is a desire to provide an article of furniture such as a school desk with a desk top having such a bead or buffer. The desk top is preferably able to have a different profile on adjacent edges so that, for example, school desks can be edge abutted as described above but still have no sharp edges on the rear edge of the desk top. 
       SUMMARY OF THE INVENTION 
       [0008]    In accordance with a first aspect of the present invention there is disclosed an article of furniture having a substantially planar substrate with at least one edge, said at least one edge being coated with an elongate layer of plastics material to form a buffer which extends along said edge, wherein said plastics layer is formed on said substrate by an injection moulding process and wherein said substrate has a surface adjoining said coating layer which is curved when viewed in a cross-section which is transverse to the longitudinal axis of said buffer. 
         [0009]    Preferably the exterior of the buffer is curved when viewed in the transverse cross-section. 
         [0010]    Preferably the substrate has first and second adjacent edges which are substantially perpendicular to each other, said buffer extends along both said edges, said substrate first edge and the exterior surface of said buffer adjacent said first edge are curved, but the exterior surface of said buffer adjacent said second edge is substantially flat, whereby two like said articles of furniture can have their substrates edge abutted by edge abutting said buffers adjacent said second edges. 
         [0011]    Preferably the substrate second edge is substantially flat when viewed in the transverse cross-section. 
         [0012]    In accordance with a second aspect of the present invention there is disclosed a method of forming an article of furniture having a buffer, said method comprising the steps of: 
         [0013]    (i) forming at least one edge of a substantially planar substrate, along which said buffer is to extend, to have a substantially curved surface when viewed in the direction of a cross-section taken transverse to the longitudinal axis of said buffer, and 
         [0014]    (ii) injection moulding said buffer to said curved edge. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    A preferred embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which: 
           [0016]      FIG. 1  is a transverse cross-sectional view through a desk top and edge beading of a first form of prior art, 
           [0017]      FIG. 2  is a view similar to  FIG. 1  but of a second form of prior art, 
           [0018]      FIG. 3  is a view similar to  FIGS. 1 and 2  but of a first embodiment of the present invention taken along the line III-III of  FIG. 6 , 
           [0019]      FIG. 4  is a view similar to  FIG. 3  but taken along the lines IV-IV of  FIG. 6 , 
           [0020]      FIG. 5  is a view similar to  FIG. 4  but of another embodiment; 
           [0021]      FIG. 6  is an exploded perspective view from above showing the right hand side edge of a left desk being edge abutted against the left hand side edge of a right desk, the working surfaces of both desks being illustrated in transparent fashion, and 
           [0022]      FIGS. 7A-7C  are plan views of various different desk and table tops. 
       
    
    
     DETAILED DESCRIPTION 
       [0023]    As seen in  FIG. 1  a prior art table top  1  or desk working surface, is viewed in cross-section and has a upper surface  2  and a lower surface  3 . A side edge  5  of the table top is illustrated and is flat in the cross-sectional view illustrated in  FIG. 1 . If the table top  1  is circular then there is only one side edge  5  and it is essentially cylindrical. If the table top  1  is rectangular then there are four side edges  5  the adjacent ones of which are substantially perpendicular and intersect to form the four corners (not illustrated) of the table top  1 . 
         [0024]    As illustrated in  FIG. 1  the side edge  5  is provided with a continuous groove  6  which extends along the side edge  5 . A side bead  7  is formed with a stem  8  which protrudes from a flat inner surface  9 . The side bead has a outer surface which can be curved as indicated at  11  or can be flat as indicated at  12 . The free end of the stem  8  is provided with a barbed head  13 . 
         [0025]    In order to attach the side bead  7  to the table top  1 , the stem  8  is forced into the groove  6  thereby compressing the barbed head  13  and providing a good frictional fit between the side bead  7  and the table top  1 . Normally no glue is used, however, this can be provided if desired. 
         [0026]    The table top  1  with its side bead  7  suffers from a number of disadvantages, one of which is that students provided with a school desk having such an arrangement are liable to introduce a knife or screwdriver into the crack formed between the table top  1  and the flat inner surface  9  so as to prise the side bead  7  away from the table top  1 . 
         [0027]    Turning now to  FIG. 2 , illustrated therein is a table top  21  having an upper and lower surface  22  and  23  respectively and a side bead  27  of rectangular cross-section which abuts a flat side edge  25  of the table top  21 . In one form of the prior art arrangement illustrated in  FIG. 2  the side bead  27  is extruded as a rectangular strip of plastics material and then adhered to the side edge  25 . In another form of the prior art illustrated in  FIG. 2  the side bead  27  is injection moulded directly onto the side edge  25  by placing the table top  21  into the mould used to form the injection moulded side bead  27 . 
         [0028]    A weakness of the arrangements of  FIGS. 1 and 2  where the side bead  27  is formed from an extruded strip, is that the ends of the strip must be joined together. This join represents a line of weakness which may be attacked by students of a malicious disposition. This problem is overcome by the abovementioned prior art arrangement of injection moulding the side bead  27 . 
         [0029]    Where the table top  21  is circular, then the side edge  25  is cylindrical and so too is the side bead  27 . However, where the table top  21  is rectangular the side bead  27  extends around the four corners and the table top  21  may be abutted with a like table top  21  because of the flat nature of the side bead  27 . However, the edge of the table top  21  formed by the upper edge  28  of the side bead  27 , even if slightly bevelled, forms a relatively sharp edge against which the under side of a forearm of a student or other person sitting at a table having the table top  21 , comes into contact. It would therefore be desirable to remove the sharp edge if possible. 
         [0030]    A first embodiment of the present invention is illustrated in  FIGS. 3 ,  4  and  6 . As seen in  FIG. 3 , a desk top  31  is provided with upper and lower surfaces  32 ,  33  respectively which are preferably formed from a tough durable laminate such as that sold under the Registered Trade Marks FORMICA and LAMINEX. 
         [0031]    One edge of the desk top  31  is provided with a buffer  37  having a generally parabolic or bull nose profile which does not present any sharp edge to the user. Prior to creation of the buffer  37 , the side edge  35  of the table top  31  is routed so as to form the curved profile illustrated in  FIG. 3  having two steps or discontinuities  36 . The buffer  37  is preferably formed from polypropylene by injection moulding the buffer  37  in a mould in which the desk top  31  has been positioned. In this way the outer surface of the buffer  37  can be formed flush with the upper and lower surfaces  32 ,  33  and excellent adhesion between the buffer  37  and the side edge  35  is obtained. 
         [0032]    The other side edge of the desk top  31  is illustrated in  FIG. 4  and is provided with an injection moulded substantially flat buffer  47  which is joined to a substantially flat edge  48 . 
         [0033]    Preferably the buffer  47  has an extended underside  74  which is substantially flush with the underside  33  of the desk  31 . The underside  74  is formed by filling with plastic, during the injection moulding process, a rebate which is routed out of the desk top  31 . Such an underside extension  74  is particularly useful for strengthening particularly the corners of desks and tables with folding legs. Such desks with folding legs are used at examination time, are stored away when not required, and can be subject to particularly abusive behaviour because of their light weight. Because the legs fold into a space within the perimeter of the desktop, it is the edges of the desk top which bear the brunt of this abuse. 
         [0034]    The interior of the table top  31  is preferably formed from particle board which takes the form of small timber particles adhered together in a glue-like matrix. This is inexpensive but does not present an attractive surface. Thus all surfaces are covered by means of the laminates  32 ,  33  and the buffers  37 ,  47 . 
         [0035]    Turning now to  FIG. 6 , two desks  40  and  50  are illustrated in  FIG. 6  with the top of each desk being illustrated in transparent fashion. In  FIG. 6  the left hand desk  40  has a right hand side edge  41  as well as a front edge  42  and rear edge  43 . The left hand side edge of the desk  40  is not visible in  FIG. 6 . Also illustrated in  FIG. 6  is the right hand leg  46  of the desk  40 . 
         [0036]    Turning now to the desk  50 , part of its front edge  52  and part of its rear edge  53  are visible, as is the upper edge of its left hand side edge  54 . The right hand side edge of the desk  50  is also visible. 
         [0037]    It will be apparent from  FIG. 6  that the side edges  41 ,  54  with their buffer  47  are flat and can therefore be edge abutted as indicated by means of arrows A and B in  FIG. 6 . When so abutted the tops  31  of the desks  40  and  50  are substantially flush and provide a substantially continuous working surface. 
         [0038]    However, the front edges  42 ,  52  and rear edges  43 ,  53  are provided with the curved buffer  37  and thus do not have any sharp edges. In this way a comfortable surface for the forearms of students sitting at the desks  40  and  50  is presented. 
         [0039]    Turning now to  FIG. 5 , another profile is illustrated having a buffer  57  with a lip  58  which is proud of the upper surface  32  and can thus function as a moisture or spill trap which is useful for scientific bench tops, for example. 
         [0040]    As seen in  FIGS. 7A-7C  various table and desk tops  61 - 69  are illustrated in plan view. Tops  61 ,  63 ,  65  and  69  are rectangular, top  62  is square, tops  67  and  68  are trapezoidal and top  66  is circular. Top  64  is substantially square but is provided with an indented edge  73  which is recessed when viewed in plan to partially accommodate the torso of a person sitting at the desk or table with such a top  64 . 
         [0041]    The foregoing describes only some embodiments of the present invention and modifications, obvious to those skilled in the furniture arts, can be made thereto without departing from the scope of the present invention. 
         [0042]    The term “comprising” (and its grammatical variations) as used herein is used in the inclusive sense of “including” or “having” and not in the exclusive sense of “consisting only of”.