Abstract:
A sawhorse with the horizontal rail having an inner chamber housing a plurality of linearly aligned, upwardly projecting work support elements above a laterally moveable skid. The skid has a plurality of linearly aligned upwardly projecting ramps. The ramps elevate the work support members above the rail for supporting workpieces above the rail when the skid is moved in one direction and allow the work support elements to retract into the chamber when the skid is moved in the opposite direction.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application claims priority to provisional application Ser. No. 60/196,583, filed Apr. 13, 2000. 
     
    
     
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT  
         [0002]    Not Applicable.  
         BACKGROUND OF THE INVENTION  
         [0003]    The present invention relates to an apparatus for supporting workpieces on a sawhorse, and more particularly, to an apparatus for alternatively supporting workpieces directly atop a sawhorse beam or supporting workpieces above the sawhorse beam on a series of adjustable pegs to provide operational clearance for tools between the workpieces and the beam.  
           [0004]    “Sawhorse” is a generic name for a device that generally consists of a horizontal beam or rail supported by two pairs of opposed legs that descend from the rail, generally at an angle away from each other, to provide stability to the rail. While most sawhorses stand about 30 to 36 inches tall, some collapse or fold by various means for easier storage and transportation.  
           [0005]    Sawhorses are used by carpenters, tradesmen and others, to support objects, workpieces and materials, such as boards and plywood, (collectively “workpieces”) during construction-type operations. These types of operations cover a broad range of activities, including sanding, buffing, cutting, drilling, nailing and gluing. Many of the operations are accomplished using motorized “power” tools, such as circular saws, jig saws and power drills. During operation, many tools, and in particular power tools, must penetrate below the bottom surface of the workpiece. That is, to cut a board in half, for example, a portion of the blade on a circular saw actually extends below the bottom surface of the board. Similarly, to drill a hole through a plank, the drill tip must fully penetrate through the bottom surface of the plank.  
           [0006]    Such penetration can cause difficulties when, for example, the cutting or drilling traverses the area of the workpiece that is resting directly on the rail of the sawhorse. In order to prevent damage to the workpiece, the sawhorse or the tools, the workpiece must be repositioned on the support surface during the operation. In fact, the workpiece must often be repositioned multiple times to complete a single operation. For example, when ripping a four foot by eight foot sheet of plywood with a circular saw, the plywood sheet may be repositioned several times to avoid cutting the rail of the sawhorse. This imparts inefficiencies in all such operations and may cause the user to take unnecessary risks to the equipment, the sawhorse or himself in order shorten the time required to perform each such operation.  
           [0007]    Accordingly, it would be desirable to have a sawhorse design that allows operations to be performed on a workpiece supported by the sawhorse without risking damage to the workpiece or the sawhorse, and without requiring time consuming steps to reposition of the workpiece.  
         SUMMARY OF THE INVENTION  
         [0008]    The present invention resides in a sawhorse rail design that elevates the supported workpiece above the surface of the rail itself, such that operations that would otherwise require repositioning the workpiece atop the sawhorse to avoid encountering the rail can be performed without such repositioning. This improvement allows the carpenter or other craftsman to utilize the sawhorse more efficiently without the concern that an operation may unintentionally cause damage to the rail, the tools or the workpiece.  
           [0009]    Generally stated, the invention includes a novel rail. The rail has a top surface which include plurality of linearly aligned holes along its length, two horizontally extending side walls and two end walls which define an inner cavity. Within the cavity is a series of interconnected, linearly aligned, upwardly protruding support members operatively associated with an apparatus for urging the support members through the openings in the top surface of the rail to create a workpiece support surface above the rail. Hence, the support members are adjustable from a first position above the top of the rail to a second position below the top of the rail.  
           [0010]    The support members rest atop a plank which rests on a skid slidably positioned within the cavity. The plank is free to move vertically, but not laterally. The plank has a series of slots formed in its length which correspond to a series of ramps positioned on the skid below the plank. The skid can move laterally. The relationship between the slots and the ramps is such that by moving the skid in one lateral direction, one side of each of the slots is forced to ride up the incline of its corresponding ramp, thereby raising the plank carrying the support members to a position where the support elements protrude through the openings in the top wall of the rail. When the skid is moved in the other lateral direction, the slots slide down the incline on the ramps, thereby lowering the plank and the support members. The tops of the ramps are flat to allow the plank to rest atop the ramps and maintain the support members in the first position above the rail. A handle, attached to the skid through a slot formed in one of the sides of the rail, enables the user to impart the desired lateral movement to skid so as to raise or lower the support members.  
           [0011]    Hence, the present invention provides a simple to control mechanism that allows the user to selectively and quickly raise or lower the workpiece atop the sawhorse rail depending on the operation being performed on that workpiece.  
           [0012]    In addition, the rail in the present invention is designed to reside atop both fixed and collapsible legs or supports. The present invention is readily adaptable to numerous shapes and sizes, and may be constructed of many materials, such as wood, plastics and metals. Other objects and additional features of the present invention will be in part apparent and in part pointed out hereinafter. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a perspective view of the preferred embodiment of the novel sawhorse rail atop a sawhorse, shown in phantom, with the support members in the lowered position within the body of the rail;  
         [0014]    [0014]FIG. 2 is a perspective view of the embodiment of FIG. 1, with the support members in the fully raised position above the surface of the rail;  
         [0015]    [0015]FIG. 3 is an exploded view of the embodiment of FIG. 1;  
         [0016]    [0016]FIG. 4 is a perspective view of one of the ramp elements of the sawhorse rail;  
         [0017]    [0017]FIG. 5 is a cross-sectional side elevation of the sawhorse rail, showing the support members in the lowered position within the body of the rail;  
         [0018]    [0018]FIG. 6 is a cross-sectional side elevation of the preferred embodiment, showing the support pegs in the fully raised position above the body of the rail;  
         [0019]    [0019]FIG. 7 is a perspective view of the sawhorse rail attached to a pair of folding leg braces with a folding shelf below the rail, showing the legs fully open and the shelf locked flat;  
         [0020]    [0020]FIG. 8 is a perspective view of the embodiment of FIG. 7, showing the legs closed together and the shelf folded up between the legs; and  
         [0021]    [0021]FIG. 9 is perspective view of one end of the folding shelf of the modified embodiment, showing the tabs and grooves at the center hinge. 
     
    
       [0022]    Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.  
       DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0023]    The preferred embodiment of the novel sawhorse rail is indicated generally at  10  (FIGS. 1 and 2). The rail  10  may be used independently or it may be fastened to a set of sawhorse legs, as depicted in ghost images in FIGS. 1 and 2, by any of a number of common and well-understood means, such as bolts or screws between the rail  10  and the legs, a clamping device, or glues such as epoxy. Alternatively, the rail  10  may be simply placed atop a set of legs without firm attachment.  
         [0024]    The sawhorse rail  10  includes a top wall  11 , a first vertical side wall  12 , a second vertical side wall  14 , a base  16 , and a first vertical end wall  18  and second vertical end wall  20 . When fully assembled, the body of the rail  10  is hollow, i.e. having an inner cavity defined by the recited walls and base. Near the center of the lower edge of the side wall  12  is a horizontal notch  22 .  
         [0025]    Referring to FIG. 3, it can be seen that a track  23  is formed in, and runs the full horizontal length of the centerline of the top surface of the base  16 . A horizontal notch  25  is formed in the side of the track  23  that aligns in registry with the notch  22  in the side wall  12  to form a handle opening along the side of the rail  10 . A slidable skid  24  rests in the track  23 . The skid  24  is slightly thinner than the width of the track  23 , and somewhat shorter than the base  16 . This allows the skid  24  to slide freely within the track  23 , between the end walls  18  and  20  within the body of the rail  10  as will be explained below.  
         [0026]    A series of linearly aligned, equally shaped ramps  26  are fixedly attached to the top surface of the skid  24 . Each of the ramps  26  (FIG. 4) has a rectangular base  28  with three vertical walls  30 ,  32  and  34 , an incline  36 , and a short, flat, horizontal platform  38  at the top of the incline  36 . The ramps  26  are equidistant apart from one another along the skid  24 , and oriented such that each incline  36  ascends from the skid  24  in the same angular direction. A handle  40  is also fixedly attached to the skid  24 . The handle  40  is positioned along one side of the skid  24  such that the handle corresponds with and extends horizontally through the opening formed by the notches  22  and  25  in the side of the rail.  
         [0027]    A plank  42  rests atop the skid  24  inside the body of the rail  10 . The plank  42  is generally the same width, but is longer than the skid  24 , such that the ends of the plank  42  nearly abut the inner surfaces of the end walls  18  and  20 . The plank  42  has a series of linearly aligned rectangular openings  44  between each end. The number of the openings  44  is the same as the number of the ramps  26  on the skid below. Each of the openings  44  locates directly over one of the ramps  26  when the skid  24  is close to or abuts the inner surface of the first end wall  18 . Because the openings  44  are slightly longer and wider than the base  28  of the ramps  26 , the openings  44  can readily slide up and down over the ramps  26 .  
         [0028]    A set of equally dimensioned upwardly extending support members, shown as pegs  46 , are attached in a along the top of the plank  42 . The pegs  46  are positioned on the plank  42  to align with corresponding circular holes  48  in the top wall  11  of the rail  10 . The holes  48  are slightly larger in diameter than the pegs  46 , such that the pegs  46  may move freely up and down within the holes  48 . It will be appreciated that pegs  46  could have a rectangular or other cross section if desired, provided the holes  48  have a complimentary shape. The height of the pegs  46  is slightly less than the distance from the top of the plank  42  to the top of the holes  48  (FIG. 5).  
         [0029]    It is evident to one skilled in the art that when the skid  24  is resting at a first position adjacent the first end wall  18 , the ramps  26  will fit fully inside the openings  44  in the plank  42 . In this alignment, the plank  42  rests atop the skid  24 , and the tops of the pegs  46  are lower than the tops of the holes  48 . When the handle  40  is pushed toward the second end wall  20  (FIG. 6), the skid  24  and the ramps  26  travel in the same direction toward end wall  20 . Because the plank  42  is constrained from lateral movement by the end walls  18  and  20 , the ramps  26  are forced to slide under the edges of the openings  44  adjacent the bottom of the inclines  36 . The force of the ramps  26  wedging under the edges of the openings  44  causes the plank  42  to ascend in a level fashion up along the inclines  36 . This, in turn, raises the pegs  46  on the plank  42  through the holes  48 . As the handle  40  moves further toward the second end  20 , the pegs  46  will continue to ascend through the holes  48  until the inclines  36  are entirely under the plank  42 . At this point, the plank  42  will then slide across, rest upon, the platforms  38  atop the ramps  26 , and the pegs  46  will be fully extended above the surface of top wall  11  of the rail  10 . Two or more of the tops of the pegs  46 , in cooperation with one another, thereby form an elevated support surface for workpieces atop the sawhorse.  
         [0030]    When the handle  40  is then actuated in the opposite direction, i.e. toward the first end wall  18  (FIG. 7), the skid  24  and the ramps  26  travel in the same direction. As before, the plank  42  is still constrained from lateral travel by the ends  18  and  20 . Now, however, the ramps  26  slide along the platforms  38  under the plank  42  until the platforms  38  are fully within the openings  44 . Thereafter, the plank  42  begins to descend as the ramps  26  slide back into the openings  44  along the inclines  36 . This causes the pegs  46  to simultaneously descend through the holes  48 . As the handle  40  moves further toward the first end  18 , the pegs  46  will continue to descend through the holes  48  until the ramps  26  are entirely within the openings  44  and the plank  42  is again resting atop the skid  24 . At this point, the tops of the pegs  46  will be below the top of the holes  48  in top wall  11  of the rail  10 .  
         [0031]    [0031]FIGS. 7 and 8 show another embodiment of the present invention in which a rail  10 ′, having a top wall  11 ′, side walls  12 ′ and  14 ′, a base  16 ′, and end walls  18 ′ and  20 ′, is mounted on a collapsible sawhorse S′. In this embodiment, two equally shaped leg braces  50  are pivotally attached along their tops to the side walls  12 ′ and  14 ′ of the rail  10 ′ by a pair of hinges  52 . Each of the leg braces  50  is a flat plate having a generally rectangular top portion  51  with two broad, flat-bottomed legs  53  at the opposite end. The bases  54  of both legs  53  on each leg brace  50  are parallel to one another. The leg braces  50  can fold in towards one another along the side walls  12 ′ and  14 ′, as in FIG. 8. The hinges  52  are both horizontal, parallel to one another, and located at the same height above the bottom of the rail  10 ′. In order to accommodate the hinge  52 , notches  22 ′ and  25 ′, are in a higher position along side  12 ′ than the notches  22  and  25  along the side  12  in the preferred embodiment. This requires that handle  40 ′ attach along the skid  24 ′ and descend vertically within the body of the rail  10 ′ to attach to skid  24 ′.  
         [0032]    A folding shelf  55  is positioned between the leg braces  50 . The shelf  55  is formed from two generally rectangular plates  56  that are pivotally connected to one another along the center of the shelf  55  by a hinge  58 . A series of interlocking tabs  60  extend from the centermost edges of the plates  56  above the hinge  58 . The tabs  60  are shaped to lay flat in a series of complementary shaped grooves  62  (FIG. 9) on the opposed plate  56  when the plates are coplaner and the shelf  54  is flat. (FIG. 7). The tabs  60  therefore form a stop that prevents upward rotation of the plates  56  about the hinge  58  beyond the point where the plates  56  are coplaner.  
         [0033]    Each long side  63  of the shelf  55  is parallel to the hinge  58  and pivotally attaches to each of the four legs  53  by hinges  64 . The hinges  64  on each leg brace  50  are coaxial with one another and run horizontally along the inner sides of the legs  53 . On each of the leg braces, the hinges  64  are both equidistant from the base of the legs  53 .  
         [0034]    Hence, when the leg braces  50  are closed together, as in FIG. 8, the shelf  55  is folded in half and extends vertically above the hinges  64  between the legs  53 . When the leg braces  50  are pivotally opened away from one another about the hinges  52 , the two plates  56  begin to rotate about the hinges  64  at their outer ends and simultaneously rotate about the hinge  58  at their center, causing the center of the shelf  55  to lower. As the center of the shelf  55  moves downward, the tabs  60  also move from a nearly vertical orientation toward a horizontal orientation. The leg braces  50  can continue to rotate open until the shelf  55  is fully horizontal. At that point, the tabs  60  lock into the grooves  62 , the top of the shelf  55  is flat, and the structure of the shelf  55 , being fully extended, prevents the leg braces  50  from opening further. The shelf  55  has a width such that when the leg braces  50  are fully opened, the distance between the legs  53  are far enough apart to provide ample stability while maintaining a suitable working height for the crown  11  of the sawhorse.  
         [0035]    The present invention, therefore, enables the user to easily, controllably, and rapidly raise a workpiece supported by the rail  10  above the top of the top surface rail  10 . This enables the user to perform various operations on the workpiece without repositioning. By simply sliding the handle  40  in one direction, the workpiece can be raised above the rail  10  on the pegs  46 . By simply returning the handle  40  to its original position, the workpiece will be lowered back onto the top wall  11  of the rail  10 . The rail  10  can be located on virtually any solid work surface, such as the on the ground, a tabletop, a bench, a chair, etc., or the rail  10  can be configured atop a sawhorse. Thus, the present invention greatly reduces the risk of damage to the work surface or the sawhorse, and the tools, and virtually eliminates the need to reposition workpieces on the rail  10  to avoid contact between the rail  10 , the work surface or the sawhorse, and various tools during operation. Additionally, embodiments of the present invention may also include collapsible or telescoping legs that enable ready storage and transport of the rail  10 , and rapid set-up to a sawhorse.  
         [0036]    Other variations on the basic apparatus are also available. For example, the base  16  could be formed without the track  23  such that the skid  24  simply rests atop the base  16  within the body of the rail  10 . The handle  40  could be located at any position along either of the sides  12  or  14  of the rail  10 , or extend out from either of the ends  18  or  20 , where the handle would be pushed and pulled. The number of the ramps  26  and the openings  44  can vary from one to many. Similarly, the number of the pegs  46 , and the holes  48  can be varied from one to many. Bearing, bushings and other friction reducing devices can be placed at various locations throughout the apparatus, such as between the skid  24  and the base  16 , between the skid  24  and the plank  42 , and in the openings  44  and  48 , to enhance the functioning of the apparatus without deviating from the scope of the invention. Further, the sides of the openings  44  nearest the bottom of each incline  36  can be rounded, angled, or otherwise shaped to further enhance the sliding capability of the ramps  26  within the openings  44 . Similarly, bearings or bushings can be incorporated along the same side of the openings  44 .  
         [0037]    In addition, the dimensions of the apparatus can vary significantly, including, but not limited to, widening or thinning the crown  11 , the ramps  26 , the skid  24 , the plank  42  and the base  16 . The ramps  26  can be exchanged with one or more other components that will enable the plank  42 , and the pegs  46  or other similar supports, to rise within the rail  10  by moving the handle  40 . The angle of the inclines  36  for the ramps  26  can be varied to virtually any angle less than 90 degrees, and can be oriented toward either the end  18  or the end  20 . The inclines  36  on the ramps  26  can be concave or convex. The shape of the pegs  46  and their associated holes  48  can be varied to virtually any cross-sectional shape. A locking mechanism or device can be employed to lock the skid  24  into one or more desired positions. Finally, each of the components of the invention can be manufactured from a variety of materials, including, but not limited to, plastics, metals and woods, so long as the apparatus maintains the same functionality and the necessary structural integrity.  
         [0038]    Springs or other devices may be incorporated in the apparatus to apply forces against certain components. For example, springs can be placed around one or more of the pegs  46  to apply a force against the top of the plank  42  that will hold the plank  42  in the downward-most position within the rail  10  when the additional elevation is not needed. Anti-skid material can be added to components of the apparatus, such as atop the pegs  46 . Two or more smaller hinges can be substituted for any of the long hinges  52 ,  58  and  64 , so long as sufficient structural integrity is maintained.  
         [0039]    As various changes could be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.