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This application claims the benefit of U.S. Provisional Application No. 60/119,691, filed Feb. 11, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to traffic barricades and more particularly to a traffic barricades of the sawhorse variety. 
     Roads, highways, sidewalks and other areas of vehicular and foot traffic are frequently subject to maintenance and reconstruction activities. Typically, such maintenance interrupts the traffic pattern and requires a detour from normal traffic flow. The principal highway warning device in a construction zone is the traffic barricade. This device typically comprises a horizontal reflective member which has a large face or surface structure to provide immediate visual recognition during both daylight and nighttime hours. This horizontal member is typically supported by two pairs of legs which are attached to form a type of sawhorse configuration. 
     Originally, such sawhorse traffic delineators were constructed of wood. A horizontal board was mounted to vertically inclined boards in the referenced sawhorse configuration using nuts and bolts. This construction requires a host of parts and labor to assemble the traffic delineator. Such barricades were heavy, costly and difficult to stack. Further these barricades were prone to damaging any vehicle that struck the barricade. 
     There are a variety of other constructions of sawhorse traffic barricades, all with certain advantages and disadvantages. What is needed then is a durable, lightweight sawhorse barricade of simple construction that can be easily constructed and stored. 
     SUMMARY OF THE INVENTION 
     The preferred embodiment of the invention is a traffic barricade comprised of substantially identical legs forming traffic barricade supports that are used to make the traffic barricade. The traffic barricade supports are rotatably joined together at one end of each leg to allow them to pivot. The traffic barricade supports are themselves joined together with one or more rectangular panels and reflective sheeting is applied to the panels, forming the traffic barricade. 
     Thus, the invention requires only one type of leg, a pivot mechanism and one or more panels to form the traffic barricade. 
     In the preferred embodiment two identical legs are pivotally attached at one end to form a traffic barricade support. Two or more traffic barricade supports are attached to one side of a rectangular panel to create a traffic barricade. Although in the preferred embodiment the panel is rectangular, any shape presenting a substantially planar surface to the two or more traffic barricade supports may be used as a panel. 
     The leg has a triangular cross section with a narrow side, a wide side oriented substantially normal to the narrow side and a hypotenuse side. There is a void or hole formed at a first end of the leg to create a bore through the wide side and the hypotenuse side through which a pivot may be fitted. The second end of the leg is designed to contact the surface supporting the traffic barricade support. 
     In the preferred embodiment the legs are hollow and made of blow-molded plastic for durability, economy and lightness. In an alternative construction, for example, the legs may be made of roto-molded plastic, metal, and they may be solid or hollow. 
     The pivot may be a bolt, a cylinder or other suitable member to allow two legs to be pivotally hat attached so that they may rotate between a closed position, with the legs substantially parallel, to an open position where the legs are relatively oriented at an angle. In the preferred embodiment a zinc-plated steel cylinder is used. 
     The two identical legs of a traffic barricade support are pivotally attached at their first ends in relatively opposite orientation, so that the hypotenuse sides of the two legs face each other. In this manner one leg may nest inside the other in the closed position and the traffic barrier support more compactly folds together. 
     The maximum angle that the two legs of a traffic barricade support can be opened in the open position is limited by a stop extending outwardly from the first end of the narrow side of each leg. Each stop has a contact surface that, when a first leg is pivotally attached to a second leg, engage to prevent further opening of the traffic barricade support at a predetermined maximum angle. The second end of the leg is beveled so that when the predetermined maximum angle of the traffic barrier support has been reached, the second end is substantially parallel to the ground or other supporting surface. Additionally, the triangular cross section of each leg allows a greater sectional modulus because the area of the cross section of the leg is maximized. 
     In order to facilitate the stacking of traffic barricades, in the preferred embodiment the narrow side of each leg is formed to have a convexly curved surface first portion and a second portion that is a concavely curved surface. The concavely curved surface and the convexly curved surface are complementary in size and shape. 
     The convex and concave portions formed on the narrow side of the leg allow traffic barricades made from such legs to be securely stacked. The traffic barricades are stacked in alternating opposite orientations so that the convex portions of the legs of one traffic barrier will fit closely within the concave portions of another traffic barrier. In this manner traffic barriers formed from these legs stack securely and will be less likely to shift or slide in a stack of traffic barriers. 
     Although these two portions may be of any suitable shape, they are preferably rectangular in shape and formed on opposite ends of the narrow side of the leg. Reflective sheeting may be applied to the panel to make the traffic barricade more visible to drivers. 
     Additional aspects and advantages of the present invention are set forth in the following description and claims, particularly when considered in conjunction with the accompanying drawings in which like parts bear like reference numerals. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a traffic barricade. 
     FIGS. 2 a ,  2   b ,  2   c  and  2   d  are four side views of the leg of the traffic barricade. 
     FIG. 3 is an exploded view of the two legs of a traffic barricade support and their pivoting mechanism. 
     FIGS. 4 a  and  4   b  are detail views of the cylinder pivot, FIG. 4 b  is a side cutaway view. 
     FIG. 5 is a side view of a traffic barricade support with the legs in the closed position, 
     FIG. 5 a  is a bottom view of  5 . 
     FIG. 6 is a side view of a traffic barricade support with the legs shown in a partially open position. 
     FIG. 7 is a side view of a traffic barricade support with the legs shown in the open position. 
     FIG. 8 is a bottom perspective view of a traffic barricade support in a partially open position. 
     FIG. 9 is a top view of a traffic barricade support in the closed position. 
     FIG. 10 is a top view of a traffic barricade support in the open position. 
     FIG. 11 is side view of stacked traffic barricades. 
     FIG. 12 is a perspective view of a traffic barricade. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a traffic barricade  1  made of two sets of legs  10  and  12  joined together with panels  9 . Each set of two legs with a pivot is collectively referred herein to as a traffic barricade support. The legs of each traffic barricade support are joined by a pivoting mechanism  14 , hereinafter termed a pivot, and in the preferred embodiment the pivot is a cylinder made of steel. The pivot  14  may be made of metal and or other materials, such as plastic or composite materials. Both legs  10  and  12  are of the same construction, therefore only a single leg design is needed for all the legs of the traffic barricade, with the same design of leg being used for each of the four legs. Other embodiments of the invention may have different but substantially identical leg designs from the preferred embodiment. 
     FIGS. 2 a - 2   d  shows an individual leg from four side views. FIG. 2 a  shows the leg from the hypotenuse side  34 . The end of the leg  15  is beveled to allow it to stand parallel or flush to a supporting surface when it is functioning as leg of a traffic barrier. Recesses  50  are shown which allow a screw to recede when it is used to affix a panel. In this view, the recesses  50  are shown with the walls  51  between the flat surface  32  of the recess and the narrow leg side  30  (shown at  2   d ). There is a panel hole  31  that corresponds to the center of recess flat surface  32  through which a panel mounting screw is fitted. Stop  22  is shown that forms a stop contact surface  23 . The stop contact surface  23  forms an angle theta with the major axis  24  of each leg. The face of the contact surface  23  can be seen in FIG. 2 b . FIGS. 2 a  and  2   c  show hole  13  that creates a bore from hypotenuse side  34  through wide side  32 . FIGS. 2 a ,  2   c  and  2   d  show convexly curved surface  60  at the first end of the leg and concavely curved surface  62  at the second end. When the legs are assembled into the traffic barricade of FIG. 1, a plurality of traffic barricades may be securely stacked because the convexly curved surface  60  fits into the concavely curved surface  62 , as shown in FIG.  11 . 
     Any suitable plastic may be used to manufacture the legs. In a preferred embodiment of the invention, the plastic is high density polyethylene with a density of 0.96. Blow molding is the preferred method of manufacturing the both because it produces a strong barricade leg and also because it is more economical to use this method. 
     FIG. 3 is an exploded view showing the pivot mechanism  14  of the preferred embodiment as it fits into legs  10  and  12  to make a traffic barricade support. Pivot mechanism  14  is comprised of a cylinder  18  having a flange  16 , an end cap  19  and bolt  20 , and a nut  52  that is used in conjunction with the bolt  20  shown in the end cap washer  54 . 
     When the pivot is assembled, the cylinder  18  extends through the holes  13  of legs  10  and  12 . At the end of the cylinder distal the flange, there is a narrowing or constriction  17 , also shown in the cutaway side view  4   b,  formed to retain end cap  19  within the cylinder. The end cap washer  54  has an inner surface that is disposed against the constriction  17  and the outside surface of leg  10  around hole  13  and the bolt  20  is affixed to nut  52  and is disposed against the outside surface of the end cap washer. Nut  52  is disposed against the inside surface of the end cap  19  within the cylinder. This configuration is preferred but not essential, the nut and bolt could be installed in the opposite direction with the bolt disposed against the inside surface of the end cap. 
     When assembled, the flange and the washer maintain the two legs and the distance between the flange  16  and washer  54  is such that the legs  10  and  12  can freely pivot. 
     FIGS. 4 a  and  4   b  show the detail of the pivot mechanism, also termed the pivot. Pivot  14  is shown with a flange  16  radially extending from a proximate end of a cylinder  18 . At the end of the cylinder distal the flange, there is a narrowing or constriction  17 , shown in the cutaway side view  4   b , formed to retain end cap  19  within the cylinder. The cylinder  18  extends from the flange  16  and through the top first ends of the legs  10  and  12  (not shown). The bolt  20  is mounted through the end cap of the mechanism and extends distally from the flange  16 . The end cap  19  of the cylinder  18  is shown to the left and the flange  16  of the cylinder  18  is shown to the right. Note that the end cap  19  and the flange  16  are located at opposite ends of the cylinder  18 . Other embodiments of the invention may have other ways of attaching the flange and the end cap to the cylinder or the parts may be unitary. Other embodiments of the invention may have other pivots also. 
     Now referring to FIG. 5, the two legs  10  and  12  are shown in the closed position nesting together. FIG. 5 a  is a bottom view of the invention in this position. As shown each leg has an approximately triangular cross section. It is to understood that the use of the terms triangular and hypotenuse in this patent are not to be strictly construed as a hypotenuse of a true right triangle, this is simply the closest geometric shape that is useful to describe the structure of the present invention. For example, as FIG. 5 a  shows the cross section of a leg is not a true triangle, but of general triangular shape. What is essential that the cross section of a leg includes a diagonal side, herein referred to as the hypotenuse, so that the hypotenuse sides of two legs will engage in the closed position and thereby nest together. In the preferred embodiment, for example, each leg includes a narrow trim side  25  sized to increase the overall width of a leg to allow sufficient mass of plastic to be used to support a particular traffic barricade and to form a hole of sufficient depth to support the flange. The appropriate additional width of the leg accorded by the trim side is a function of the material used to construct the leg and will be apparent to one of ordinary skill in the art. 
     In the preferred embodiment the surface of the leg that actually contacts the supporting surface is formed with an irregular surface, such as small bumps  27  to increase the traction of the leg on the surface. 
     The perimeter of the leg cross section of  5   a  also has two sides, narrow side  30  and wide side  32  oriented at a right angle relative to each other. The narrow side  30  is narrower than wide side  32 . The perimeter of the leg cross section also has a hypotenuse  34  extending between the two sides  30  and  32 , in the preferred embodiment connected by trim side  25 . 
     When the legs  10  and  12  are closed, as shown, the hypotenuses  34  of each legs align and engage, thus nesting the legs. 
     Now referring to FIG. 6, the legs  10  and  12  are shown in a partially open position. The legs  10  and  12  have partially opened up in a direction  38  and  40 , respectively. The directions  38  and  40  are mutually opposing, shown by arrows, and the directions are also normal to the narrow side  30  of the respective leg. 
     Attachment of a panel to the legs is straightforward. In this view, the recesses  50  are shown with the walls  51  between the flat surface of the recess and the narrow leg side  30 . The panel  9  is affixed, for example, with panel mounting screws or bolts  9 ′ that extend through panel hole  31  that corresponds to the center of recess flat surface  32  through which a panel mounting screw is fitted. Screws or bolts  9 ′ used to mount the panels remain sufficiently in the recess such that they do not to interfere with the nesting of the legs in the closed position. 
     The legs  10  and  12  of FIG. 7 are shown in the open position. At the top first ends of the legs  10  and  12  are stops  22 . The stops  22  have contact surfaces  23  which are shown engaged in mutual contact. Notice that the stops  22  have reinforcing construction  26  in order to improve the strength of the device. 
     FIG. 8 shows the legs  10  and  12  fully opened and the view is looking up from the bottom of the legs towards the pivoting point. The interior, hypotenuse side  34  of the legs are shown with recesses  50 . The recesses  50  are arranged to accommodate a screw, bolt or other attaching device that is used to mount a panel to the legs. The recess  50  has a flat surface  32  that opposes the narrow leg side  30  and a bolt extends through the wall between the recess flat surface and the narrow leg side. The narrow leg side  30  has a panel hole  31  that corresponds to the center of the recess flat surface  32  through which a panel mounting screw is fitted. 
     FIG. 9 shows the legs  10  and  12  looking down from the top while the legs are in a closed position. As shown the stops  22  are not in contact because the legs are in the closed position, the contact surfaces  23  of the stops are exposed. 
     Now referring to FIG. 10, legs  10  and  12  are shown in a top view in an open position. Note that the contact surfaces  23  of the two stops  22  extending from the top of the legs are now in contact. 
     FIG. 11 shows the assembled barricades stacked together. The individual traffic barricades stack secure because the convexly curved surface  60  of one leg stacks neatly into the concavely curved surface  62  of the legs of the traffic barrier stacked on top of it and underneath it. They may stacked one atop another in alternating orientation with the convex portion of one leg fitting in the complementary concave surface portion another traffic barricade. 
     FIG. 12 shows the use of a batten  37  to ballast a traffic barricade. Slits  39  may be cut in the legs of two hollow traffic barrier supports forming a traffic barricade to receive a batten, which may be a length of plastic. A sandbag  41  or other available ballasting object may then be placed on the batten to ballast the traffic barricade from being moved by the force of wind or rain. FIG. 12 also shows the use of reflective sheeting  43  applied to the exterior face of panels  9  to increase the visibility of the traffic barricade. 
     It will be appreciated that the invention has been described hereabove with reference to certain examples or preferred embodiments as shown in the drawings. Various additions, deletions, changes and alterations may be made to the above-described embodiments and examples without departing from the intended spirit and scope of this invention. Accordingly, it is intended that all such additions, deletions, changes and alterations be included within the scope of the following claims.

Summary:
A sawhorse type of traffic barricade constructed from identical leg units. The legs are equipped with a stop to prevent them from opening beyond a predetermined point. The legs have the cross section of a right triangle, allowing the hypotenuse sides of the legs to nest within each other. The legs may be equipped with complementary convex and concave portions to allow the barricades to be stacked securely atop one another by fitting the portions together.