FIELD OF THE INVENTION 
       [0001]    This invention relates generally to safety barricades, and, more particularly, to a modular barrier kit comprising elements that may be erected and configured to warn and/or guide traffic, cordon off and/or conceal an area, and even provide temporary shelter. 
       BACKGROUND 
       [0002]    First responders, including police, frequently must guide traffic, protect and rope off an accident or crime scene, warn pedestrians and motorists of dangerous conditions, and shelter an area and/or first responders from sun and precipitation. Unfortunately, devices readily available in police and emergency personnel vehicles are often inadequate for one or more of the aforementioned tasks. 
         [0003]    What is needed is a relatively inexpensive and lightweight kit that can be conveniently stored in a vehicle, and quickly and intuitively erected and configured, without tools, to provide a barrier to accomplish any one or more of the following: guide traffic, protect and rope off an accident or crime scene, warn pedestrians and motorists of dangerous conditions, and shelter an area and/or first responders from sun and precipitation. 
         [0004]    The invention is directed to overcoming one or more of the problems and solving one or more of the needs as set forth above. 
       SUMMARY OF THE INVENTION 
       [0005]    To solve one or more of the problems set forth above, in an exemplary implementation of the invention, a kit contains mast modules that may be erected and connected in a variety of configurations to provide a barrier to accomplish any one or more of the following: guide traffic, protect and rope off an accident or crime scene, warn pedestrians and motorists of dangerous conditions, and shelter an area and/or first responders from sun and precipitation. Each mast module includes a tubular mast that is mountable to a support base. The mast also includes a coupler with a u-shaped slot for receiving an orthogonal mast. The mast also includes bolts and key slots positioned apart from the u-shaped opening. The bolts and key slots may be used to couple masts. Using the various connections, a wide variety of framework configurations are possible. The coupler of each mast includes undulating slots for retaining signage. Each mast may also include retro-reflective elements near the coupler end of the mast. Optional additional features include a top post with a rounded end for supporting a tent-like tarp. Additionally, the base may contain batteries that supply regulated electric power to one or more outlets in the mast. Elements of a kit may be contained in a case, which may also serve as a flotation device. 
         [0006]    A modular barrier according to principles of the invention may be made using a plurality of masts, including a first mast, a second mast and a third mast. In one basic configuration, the first mast is spaced apart from and generally parallel to the second mast. The third mast is generally parallel to and releasably attached, either directly or indirectly, to the first and second masts. Various structures may be constructed using repeated coupled assemblies of this basic configuration. 
         [0007]    Each mast of the plurality of masts includes a hollow tube, a plurality of key slots and a coupling bolt. The hollow tube has a first end and a second end opposite the first end, a longitudinal axis extending from the first end to the second end, a length of at least two feet, a wall, a wall thickness, an outer surface of the wall, an inner surface of the wall, an outer diameter, an inner diameter, a first key slot adjacent to the first end, and a second key slot adjacent to the second end and in circumferential alignment with the first key slot. 
         [0008]    Each key slot is an aperture in the hollow tube. The aperture includes a first aperture portion and a second aperture portion extending from the first aperture portion. Optionally, there may be a third aperture portion extending from the first aperture portion opposite the second aperture portion. The first aperture portion has a first aperture width. The second aperture portion has a second aperture width. The second aperture width is less than the first aperture width. 
         [0009]    The coupling bolt is attached to the hollow tube between the first end and the first key slot. The coupling bolt has a shank with a shank width and shank length extending radially from the outer surface of the hollow tube and terminating at a head. The head has a head width that exceeds the shank width and exceeds the second aperture width and is not greater than the first aperture width. The shank length is at least about the wall thickness. The first aperture portion is sized and shaped to receive the head. The second aperture portion is sized and shaped to receive the shank and prevent radial removal of the head when the shank is received in the second aperture portion. 
         [0010]    In one implementation, the coupling bolt of the first mast is received in the first key slot in the third mast with the shank of the coupling bolt of the first mast is received in the second aperture portion of the first key slot in the third mast. The coupling bolt of the second mast is received in the second key slot of the third mast with the shank of the coupling bolt of the second mast is received in the second aperture portion of the second key slot in the third mast. The coupling bolt of the first mast is removable from the first key slot in the third mast and the coupling bolt of the second mast is removable from the second key slot of the third mast by rotating the third mast to align the head of the coupling bolt of the first mast with the first aperture portion of the first key slot in the third mast while aligning the head of the coupling bolt of the second mast with the first aperture portion of the second key slot in the third mast. 
         [0011]    In one implementation, more than one coupling sleeve, e.g., first and second coupling sleeves, are provided. Each coupling sleeve includes a hollow sleeve having a union end, a free end opposite the union end, and a longitudinal coupling axis extending from the union end to the free end. The union end has an inner diameter that is about equal to the outer diameter of each mast. 
         [0012]    A slot is formed in the free end of the coupling sleeve. The longitudinal coupling axis is an axis of symmetry for the slot. The slot has a semicircular shape and includes an opening having an opening width, an intermediate portion having an intermediate width, and a vertex. The distance from the vertex to the opening of the slot is greater (even if just slightly greater) than one half of the outer diameter of each mast. The intermediate width is about equal to the outer diameter of each mast. The opening width is deformable from a relaxed state to a spread state. In the relaxed state it is less than the outer diameter of each mast. In the spread state it is at least as great as the outer diameter of each mast. The slot is oriented to receive a portion of a mast oriented orthogonal to longitudinal coupling axis. 
         [0013]    In one configuration, the union end of the first coupling sleeve mates with the first end of the first mast and the union end of the second coupling sleeve mating with the first end of the second mast. The slot of the first coupling sleeve may then receive the first end of the third mast. The slot of the second coupling sleeve receives the second end of the third mast. 
         [0014]    In another embodiment, each coupling sleeve further includes a pair of spaced apart tabs between the slot formed in the free end of the coupling sleeve. Each tab including a narrow slit extending from the free end to an intermediate point between the free end and the union end and generally parallel to the longitudinal coupling axis. The narrow slit is preferably an undulating slit. Such a slit is useful for gripping tape, such as caution tape. 
         [0015]    In another configuration, the union end of the first coupling sleeve mates with the first end of the first mast and the union end of the second coupling sleeve mates with the first end of the second mast. In this configuration, a tape may extend from at least one of the undulating slits of the first coupling sleeve to at least one of the undulating slits of the second coupling sleeve. The undulating slits grip the tape. 
         [0016]    In another configuration, the free end of each coupling sleeve is sized to receive a second end of each mast in alignment with the longitudinal coupling axis. 
         [0017]    In another embodiment, additional masts, including a fourth mast and a fifth mast are provided. In this embodiment, the union end of the first coupling sleeve mates with the first end of the first mast, and the union end of the second coupling sleeve mates with the first end of the second mast, and the second end of the fourth mast is received in the free end of the first coupling sleeve. The fourth mast and the first mast are in axial alignment. The second end of the fifth mast is received in the free end of the second coupling sleeve. The fifth mast and the second mast are in axial alignment and generally parallel to the fourth mast and the first mast. 
         [0018]    In another embodiment, an additional mast, i.e., a fourth mast, and an additional coupling sleeve, i.e., a third coupling sleeve, are provided. In this embodiment, the union end of the first coupling sleeve mates with the first end of the first mast, and the union end of the second coupling sleeve mates with the first end of the second mast, and the union end of the third coupling sleeve mates with the first end of the third mast. The second end of the fourth mast is received in the free end of the third coupling sleeve. The fourth mast and the third mast are in axial alignment. The slot of the first coupling sleeve receives the first end of the third mast. The slot of the second coupling sleeve receives the second end of the fourth mast. 
         [0019]    Bases may be provided to support one or more masts vertically. One embodiment may include a first base and a second base. Each base may include a broad base having a base length that is at least three times the outer diameter of each mast, and a base width that is at least three times the outer diameter of each mast, and a base thickness that is at least as great as a distance from the second end of each mast to the second key slot of each mast (e.g., at least an inch thick). The base includes a generally central mortise (i.e., socket) that is shaped and sized to securely receive and frictionally engage the second end of each mast. The central mortise may include a base sleeve having a non-circular outer circumference shape. The base sleeve may be received securely in a central aperture in the base. The second end of the first mast may be received in the central mortise (e.g., in base sleeve of the central mortise) of the first base. The second end of the second mast may be received in the central mortise (e.g., in base sleeve of the central mortise) of the second base. 
         [0020]    In another embodiment, masts are equipped with reflectors, such as retro-reflective sleeves. Each retro-reflective sleeve includes a plurality of adjoining panels (e.g., 3) defining an interior channel bound by a plurality of exterior planar surfaces (e.g., 3). Each exterior planar surface includes a retro-reflective element. The interior channel is sized to receive each mast. Each mast includes a midpoint between the first end and the second end. The first retro-reflective sleeve receives a portion of the first mast, between the first end and the midpoint of the first mast, and is secured to the received portion of the first mast with an attachment. 
         [0021]    In another embodiment, a top mast with a rounded free end is provided for supporting a tarp or other cover without puncturing it. An exemplary top mast includes a mast with a hemispherical cap attached to the first end. The second end of the top mast is received in the free end of the first coupling sleeve. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    The foregoing and other aspects, objects, features and advantages of the invention will become better understood with reference to the following description, appended claims, and accompanying drawings, where: 
           [0023]      FIG. 1  is a front view of an exemplary barricade module according to principles of the invention; and 
           [0024]      FIG. 2  is a side view of an exemplary barricade module according to principles of the invention; and 
           [0025]      FIG. 3  is a perspective view of an exemplary barricade module according to principles of the invention; and 
           [0026]      FIG. 4  is a plan view of an exemplary barricade module according to principles of the invention; and 
           [0027]      FIG. 5  is a bottom view of an exemplary barricade module according to principles of the invention; and 
           [0028]      FIG. 6  is a perspective view of an exemplary barricade comprised of a plurality of barricade modules according to principles of the invention; and 
           [0029]      FIG. 7  is a perspective view of a portion of an exemplary barricade module according to principles of the invention; and 
           [0030]      FIG. 8  is a perspective view of coupled portions of exemplary barricade modules according to principles of the invention; and 
           [0031]      FIG. 9  is another perspective view of coupled portions of exemplary barricade modules according to principles of the invention; and 
           [0032]      FIG. 10  is another perspective view of coupled portions of exemplary barricade modules according to principles of the invention; and 
           [0033]      FIG. 11  is a perspective view of a base of an exemplary barricade module according to principles of the invention; and 
           [0034]      FIG. 12  is another perspective view of a base of an exemplary barricade module according to principles of the invention; and 
           [0035]      FIG. 13  is a symbolic representation an exemplary barricade module according to principles of the invention; and 
           [0036]      FIG. 14  is a symbolic representation of exemplary coupled barricade modules as in  FIG. 8  according to principles of the invention; and 
           [0037]      FIG. 15  is a symbolic representation of exemplary coupled barricade modules as in  FIG. 9  according to principles of the invention; and 
           [0038]      FIG. 16  is a symbolic representation of exemplary coupled barricade modules as in  FIG. 10  according to principles of the invention; and 
           [0039]      FIG. 17  is a symbolic representation of a barricade comprised of exemplary coupled barricade modules according to principles of the invention; and 
           [0040]      FIG. 18  is a perspective symbolic representation of a barricade comprised of exemplary coupled barricade modules according to principles of the invention; and 
           [0041]      FIG. 19  is a perspective view of an exemplary barricade module according to principles of the invention; and 
           [0042]      FIG. 20  is a front view of an exemplary barricade module with a top support according to principles of the invention; and 
           [0043]      FIG. 21  is a plan view of an exemplary flexible sheet for a barricade according to principles of the invention; and 
           [0044]      FIG. 22  is a perspective view of an exemplary container for a barricade kit according to principles of the invention; and 
           [0045]      FIG. 23  is an exploded side view of another exemplary base of an exemplary barricade module according to principles of the invention; and 
           [0046]      FIG. 24  is an exploded bottom perspective view of the exemplary base of  FIG. 23 ; and 
           [0047]      FIG. 25  is a section (A-A) view of an end of a mast engaging a coupling sleeve for a modular barrier according to principles of the invention; and 
           [0048]      FIG. 26  is a section view, orthogonal to section A-A, of an end of a mast engaging a coupling sleeve for a modular barrier according to principles of the invention; and 
           [0049]      FIG. 27  is a section view of a base engaging an end of a mast for a modular barrier according to principles of the invention; and 
           [0050]      FIG. 28  conceptually illustrates a dimensioned mast for a modular barrier according to principles of the invention; and 
           [0051]      FIG. 29  conceptually illustrates another dimensioned mast for a modular barrier according to principles of the invention; and 
           [0052]      FIG. 30  provides a dimensioned plan view of an exemplary coupling sleeve with two slots formed in opposed ends for a modular barrier according to principles of the invention; 
           [0053]      FIG. 31  provides a dimensioned first side view of an exemplary coupling sleeve with two slots formed in opposed ends for a modular barrier according to principles of the invention; 
           [0054]      FIG. 32  provides a dimensioned second side view of an exemplary coupling sleeve with two slots formed in opposed ends for a modular barrier according to principles of the invention; 
           [0055]      FIG. 33  provides a dimensioned plan view of a hexagonal base support with a cylindrical opening in which the end of a mast is received for a modular barrier according to principles of the invention; and 
           [0056]      FIG. 34  provides a dimensioned side view of a hexagonal base support with a cylindrical opening in which the end of a mast is received for a modular barrier according to principles of the invention; and 
           [0057]      FIG. 35  provides a dimensioned front view of an exemplary coupling bolt for a modular barrier according to principles of the invention; and 
           [0058]      FIG. 36  provides a dimensioned side view of an exemplary coupling bolt for a modular barrier according to principles of the invention; and 
           [0059]      FIG. 37  provides a dimensioned first side view of an exemplary coupling sleeve with one slot formed in a free end for a modular barrier according to principles of the invention; and 
           [0060]      FIG. 38  provides a dimensioned second side view of an exemplary coupling sleeve with one slots formed in a free end for a modular barrier according to principles of the invention; 
           [0061]      FIG. 39  provides a side and magnified section perspective view of a stiffener for a modular barrier according to principles of the invention. 
       
    
    
       [0062]    Those skilled in the art will appreciate that the figures are not intended to be drawn to any particular scale; nor are the figures intended to illustrate every embodiment of the invention. The invention is not limited to the exemplary embodiments depicted in the figures or the specific components, configurations, shapes, relative sizes, ornamental aspects or proportions as shown in the figures. 
       DETAILED DESCRIPTION 
       [0063]    Referring to  FIGS. 1 through 5  various views of an exemplary barricade module of a kit according to principles of the invention is conceptually illustrated. The module  100  includes a mast  105  extending upwardly from a base  110 . As discussed below, a mast  105  may be used without a base  110  and may be oriented horizontally or vertically, depending upon the configuration of a deployed barrier. The mast is preferably at least a few feet in length, e.g., from 2.5 to 5 feet, with 3 to 4 feet being particularly preferred. The outer diameter of the mast is preferably at least a few inches, e.g., from 2 to 6 inches in diameter. The mast is preferably comprised of a plastic material, more preferably an extruded tubular plastic material with a modulus and wall thickness to maintain sufficient rigidity and provide sufficient support during use. Non-limiting examples of suitable plastics include ABS, Acrylic Plexiglass®, Butyrate, Cellulose Acetate, Cellulose Acetate Butyrate-CAB, Cellulose Propionate, Polyethtylene such as HDPE (High Density Polyethylene), PETG, Polycarbonate Lexan®, Polypropylene, Polystyrene (H.I.P.S) and (G.P.P.S.), and PVC. While a mast  105  with circular cross section is shown, the invention is not limited to a particular shape cross section. 
         [0064]    A retro-reflector  115  is attached to the mast  105 , a few inches (e.g., two to six inches) from an end of the mast  105 . The retro-reflector  115  may be attached using one or more mechanical attachments  120 , such as nuts and bolts, rivets, snap-fit couplings or other suitable connectors. The exemplary retro-reflector  115  comprises a triangular cross-section sleeve with spaced apart retro-reflective bands. 
         [0065]    At least one key slot  125 , preferably a plurality of key slots, is provided adjacent to each end of the mast  105 . The key slot  125  is an oblong slot with a central circular opening through which the head of a bolt  130  may be admitted. The key slot  125  allows coupling of one or more additional masts. 
         [0066]    At least one coupling bolt  130  is provided between the snap fit coupler  135  and the key slot  125 . In a preferred embodiment, four bolts spaced about 90 degrees apart extend radially from mast  105 . The coupling bolt includes a head with a diameter that is less than the diameter of the central circular opening of the key slot  125 , but greater than the width of the oblong slot. The coupling bolt also includes a shank having a diameter that is less than the width of the oblong slot. Thus, when the head is received in the circular opening and slid behind the oblong slot portion, the head resists separation or withdrawal through the oblong slot. 
         [0067]    One end of the mast includes a snap fit coupler  135 . Discussed in more detail below, the coupler  135  defines an aperture (i.e., a generally u-shaped aperture) that grips the periphery of an engaged orthogonal mast  105  or an engaged aligned mast. The coupler  135  also provides undulating slits  140  for securely receiving an edge of a sign or tape. 
         [0068]    The base  110  provides sufficient area and weight to hold the mast  105  upright. The mast  105  mates with the base  110  by threading or plugging into a mating aperture in the base. The base is preferably comprised of a dense elastomer with sufficient rigidity for support and structural integrity. Reinforcing ribs  145  may be provided between cavity sections  150  in the base to enhance structural integrity while limiting the amount of material used to coserve weight and manufacturing cost. 
         [0069]    In one embodiment, a frictional engagement holds the engaged end of the mast  105  in the base. In such an embodiment, the base may contain a collar with a non-circular flange. The collar is embedded in the base, e.g., molded into the base during manufacturing. In this embodiment, the collar must withstand the temperatures of molding the base. The embedded flange resists rotation of the collar. The collar may comprise an injection molded plastic structure with surfaces to enhance frictional engagement. The collar may be comprised of a material different from the base. 
         [0070]    In another embodiment, the collar is mated (e.g., press-fit, snap-fit, threaded or bonded) into a mating socket formed (e.g., molded) in the base. In this embodiment, the collar does not have to withstand the manufacturing temperature of the base. 
         [0071]    Referring now to  FIG. 6 , a perspective view of an exemplary barricade  300  comprised of a plurality of barricade modules according to principles of the invention is conceptually illustrated. The barricade includes three upright masts  305 ,  310 ,  315  supporting three horizontal masts  320 ,  335 ,  350 . One mast  320  is coupled to supporting upright masts  305 ,  310  by coupling bolts of the upright masts  305 ,  310  extending into key slots  325 ,  330  at each end of the supported horizontal mast. Each of mast  335 ,  350  is supported at its free end by a snap fit coupler  312 ,  317 . The snap fit coupler  345  of one horizontal mast  350  receives and engages the end of the mating aligned horizontal mast  335 . Mast  335  is gripped by coupler  312  at the portion  340  between the retro-reflector and coupler of mast  335 . The use of bolts and the coupler allow the various horizontal masts to be engaged without interference because the bolts are positioned sufficiently below the coupler to avoid interference between mast  320  and mast  335 . 
         [0072]      FIG. 7  provides a perspective view of a coupler portion of an exemplary barricade module according to principles of the invention. The coupler  135  is a hollow sleeve with a generally u-shaped opening  136  flanked by undulating (i.e., wavy) slots  137 ,  138 . The undulating slots secure signs to the coupler  135 . The hollow interior of the sleeve-like coupler is sized to securely receive the mating end of an aligned mast. The u-shaped opening  136  is sized and shaped to provide a snap fit connection with an orthogonal mating mast. Coupling bolts  130  and key slots  125  are also more clearly visible in  FIG. 7 . 
         [0073]    Referring now to  FIG. 8 , a perspective view of coupled portions of exemplary barricade modules according to principles of the invention are provided. In this embodiment, the horizontal mast  106  includes a pair of opposed key slots  124 ,  126 , each having a central opening  129  flanked by narrower oblong slots  127 ,  129 . A bolt  130  of the vertical mast  105  engages the key slot  124  of the horizontal mast. This engagement positions the horizontal mast  106  below the bottom of the u-shaped opening  136  in the coupler  135 . Thus, a horizontal mast may be coupled by a bolt while another parallel or orthogonal horizontal mast may be coupled by the coupler. 
         [0074]    With reference to  FIG. 9 , another perspective view of coupled portions of exemplary barricade modules according to principles of the invention is provided. The horizontal mast  106 , is now engaged in the u-shaped opening of the coupler  135 . 
         [0075]    In  FIG. 10  another perspective view of coupled portions of exemplary barricade modules according to principles of the invention is provided. Here, an end  107  of a couple mast is aligned with the coupler  135 . The end  107  of the aligned mast is securely received in the coupler  135 . 
         [0076]      FIGS. 11 and 12  provide perspective views of a base  110  of an exemplary barricade module according to principles of the invention. The bottom of the base includes stiffening ribs  145  between depressed regions or cavities  150 . A flanged collar  114  is shown separated from the base  110 . During manufacturing, the flanged collar  114  is embedded in the base  110 . The noncircular flange  113  resists rotation. The end of the mast  105  supported by the base is frictionally engaged by the collar  114 . The mast is removable from the base, Other mountings, including threaded mountings are feasible and come within the scope of the invention. 
         [0077]      FIGS. 13 through 16  symbolically represent a mast on a base and the various connections shown in  FIGS. 8, 9 and 10 . These symbolic representations are utilized in  FIGS. 17 and 18 .  FIGS. 17 and 18  conceptually illustrate a range of connections, including a plurality of horizontal, aligned, mating masts  105 B,  105 C,  105 D joined in alignment at their couplers, as in  FIG. 10 . Similarly, a vertical mast  105 A is joined in alignment at the coupler of the mast below it. Another mast  105 E extends orthogonally from that juncture, with mast  105 E being connected by a bolt extending through its key slot, as in  FIG. 8 . The couplers of vertical masts, each having a base  110 A,  110 B,  110 C, support the plurality of horizontal aligned masts  105 B,  105 C,  105 D. A sign  205  is shown engaged in the undulating slots of a coupler. A sheet  200  is also shown attached to the framework of modules. A plurality of signs and sheets may be used to provide messages (e.g., caution, warning, do not cross, etc) and shelter and concealment. 
         [0078]    In the embodiment of  FIG. 19  a battery compartment  300  is provided in the base  110 , with a plurality of outlets  305  in the mast  105  and wiring therebetween. The batteries may be used to recharge electronic devices (e.g., phones) or power accessories, e.g., lights and fans. The outlets may comprise USB ports, 12-volt outlets or any other suitable electrical outlet that can be powered by one or a plurality of batteries contained in the base  110 . 
         [0079]    In  FIG. 20 , a front view of an exemplary barricade module with a top support according to principles of the invention is provided. The top support may be used as post for holding up a tent. The top post  310  includes removable rounded (e.g., hemispherical) caps  315 ,  320 . The top post  310  may be a hollow tube that is suitable for use for storage. Various items, such as tent stakes, may be contained in the top post. The top post  310  may be supported by one, two three or more vertically arranged masts  105 , positioning the top post at a height that is suitable for the peak of a tent. Tent material (e.g., weatherproof nylon) may then be draped over the top post and appropriately staked or otherwise secured to the ground around a framework of modules that define the periphery of the tent. In this manner, the invention may be used to deploy a tent-like shelter. 
         [0080]    With reference to  FIG. 21 , various sheets may be attached to sides of a framework constructed using the invention, such as sheet  200  in  FIG. 18 . While many flexible sheet materials may be adapted for use with the invention, one example is illustrated in  FIG. 21 . The exemplary sheet includes one or more channels  405 - 420  stitched into the sheet with one or more entrances  425 - 440 , to receive one or more stiffeners. The stiffeners may comprise bendable tent poles, such as a tent pole  450  comprised of a plurality of segments  455 - 465 , each engaged in a mating collar  470 ,  475 , with elastic cord  480  urging the segments into an engaged position. In this manner, the sheet may be relatively lightweight, while exhibiting enhanced rigidity. 
         [0081]    Modules may be provided in kit form. A kit may include a plurality of masts, bases, top posts and other elements. Several police or other first responders may combine the elements of their kits to rapidly erect a suitable structure. Some or all of the elements of a kit may be contained in a carrying case. A nonlimiting example of such a case  500  is shown in  FIG. 22 . The case includes zippered closures  505 ,  510  and carrying handles. It is sized and shaped to receive the elements and fit in the storage compartment (e.g., trunk) of a vehicle. In a preferred embodiment the case is waterproof and made of a buoyant material. In an emergency, the case may be emptied and then deployed in water as a flotation device. Additionally, if the case with the contents of the kit is dropped in water, it should float rather than sink. 
         [0082]    In  FIGS. 23 and 24  exploded views of another exemplary base of an exemplary barricade module according to principles of the invention are provided. The base  110  provides sufficient area and weight to hold the mast  105  upright. The mast  105  mates with the base  110  by threading or plugging into a mating aperture  118  in the collar  116 . The collar  116  mates (e.g., is press-fit, snap-fit, threaded or bonded) into a mating socket  119  formed (e.g., molded) in the base  110 . A non-circular flange  117  of the collar defines the extent of insertion and resists rotation of the inserted collar  116 . The mating socket  119  is shaped and sized to snugly receive the collar  116  and the flange  117 , with the flange  117  at the bottom of the base  110 . 
         [0083]    As with the base described above in relation to  FIGS. 11 and 12 , the base  110  of  FIGS. 23 and 24  may also preferably be comprised of a dense elastomer with sufficient rigidity for support and structural integrity. Reinforcing ribs  145  may be provided between cavity sections  150  in the base to enhance structural integrity while limiting the amount of material used to coserve weight and manufacturing cost. 
         [0084]    The collar  116  and flange  117  is installed (e.g., pressed) into the base  110  after the base has been manufactured. In this embodiment, the collar does not have to withstand the temperatures of molding the base. The flange  117  resists rotation of the collar. The collar  116  and flange  117  may comprise an injection molded plastic structure with textured surfaces to enhance frictional engagement. The collar  116  and flange  117  may be comprised of a material different from the base. 
         [0085]    A modular barrier according to principles of the invention is made using a plurality of masts, such as a first mast, a second mast, a third mast and possibly more masts, as conceptually illustrated in  FIG. 6 , as well as the schematics of  FIGS. 13-16 and 17-18 . In one basic configuration, the first mast is spaced apart from and generally parallel to the second mast. The third mast is generally parallel to and releasably attached, either directly or indirectly, to the first and second masts. Various structures may be constructed using repeated coupled assemblies of this basic configuration. 
         [0086]    Referring now to  FIGS. 25 through 27 , each mast of the plurality of masts includes a hollow tube  105 , a plurality of key slots  126   a,b  and a coupling bolt  130 . The hollow tube  105  has a first end  106  and a second end  107  opposite the first end, a longitudinal axis extending from the first end to the second end, a length of at least two feet, a wall, a wall thickness (t), an outer surface of the wall, an inner surface of the wall, an outer diameter (d 4 ), an inner diameter (d 5 ), a first key slot  126   a  adjacent to the first end, and a second key slot  126   b  adjacent to the second end and in circumferential alignment with the first key slot. 
         [0087]    Each key slot  126   a ,  126   b  is an aperture in the hollow tube  105 . The aperture includes a first aperture portion  128  and a second aperture portion  127  extending from the first aperture portion  128 . Optionally, there may be a third aperture portion  129  extending from the first aperture portion  128  opposite the second aperture portion. The first aperture portion  128  has a first aperture width, w 1 . The second aperture portion  127  has a second aperture width, w 2 . The second aperture width, w 2 , is less than the first aperture width, 
         [0088]    The coupling bolt  130  is attachable to the hollow tube  105  between the first end  106  and the first key slot  126   a . The coupling bolt  130  has a shank  131  with a shank width and shank length extending radially from the outer surface of the hollow tube  105  and terminating at a head  132 . The head  132  has a head width (e.g., diameter) that exceeds the shank width (e.g., diameter) and exceeds the second aperture width, W 2 , and is not greater than the first aperture width, w 1 . The shank length is at least about the wall thickness, t. The first aperture portion  128  is sized and shaped to receive the head  132 . The second aperture  127  portion (and optional third aperture portion  129 ) is sized and shaped to receive the shank  131  and prevent radial removal of the head  132  when the shank  131  is received in the second aperture portion  127 . 
         [0089]    In one implementation, the coupling bolt  130  of a first mast is received in the first key slot in a third mast with the shank of the coupling bolt of the first mast received in the second aperture portion of the first key slot in the third mast, as illustrated in  FIG. 8 . The coupling bolt of the second mast may be received in the second key slot of the third mast with the shank of the coupling bolt of the second mast is received in the second aperture portion of the second key slot in the third mast. The coupling bolt of the first mast is removable from the first key slot in the third mast and the coupling bolt of the second mast is removable from the second key slot of the third mast by rotating the third mast to align the head of the coupling bolt of the first mast with the first aperture portion of the first key slot in the third mast while aligning the head of the coupling bolt of the second mast with the first aperture portion of the second key slot in the third mast. 
         [0090]    In one implementation, more than one coupling sleeve, e.g., first and second coupling sleeves, are provided. Each coupling sleeve  135  includes a hollow sleeve having a union end  139   b , a free end  139   a  opposite the union end, and a longitudinal coupling axis extending from the union end to the free end. The union end  139   b  has an inner diameter that is about equal to the outer diameter of each mast. 
         [0091]    A slot or aperture  136  is formed in the free end of the coupling sleeve  135 . The longitudinal coupling axis is an axis of symmetry for the slot. The slot has a U or semicircular shape and includes an opening having an opening width, d 1 , an intermediate portion having an intermediate width, d 2 , and a vertex. The distance, d 3 , from the vertex to the opening of the slot is greater (even if just slightly greater) than one half of the outer diameter, d 4 , of each mast. The intermediate width, d 2 , is about equal to the outer diameter, d 4 , of each mast. The opening width, d 1 , is deformable from a relaxed state to a spread state. In the relaxed state it is less than the outer diameter, d 4 , of each mast. In the spread state it is at least as great as the outer diameter, d 4 , of each mast. The slot  136  is oriented to receive a portion of a mast oriented orthogonal to longitudinal coupling axis. 
         [0092]    In one configuration, the union end  139   b  of a first coupling sleeve mates with the first end of a first mast and the union end  139   b  of a second coupling sleeve mates with a first end of a second mast. The slot of the first coupling sleeve may receive the first end of a third mast, as illustrated in  FIG. 9 . The slot of the second coupling sleeve may receive the second end of the third mast. 
         [0093]    Each coupling sleeve may further include a pair of spaced apart tabs  137   a ,  138   a  between the slot  136  formed in the free end  139   a  of the coupling sleeve  135 . Each tab  137   a ,  138   a  including a narrow slit  137 ,  138  extending from the free end  139   a  to an intermediate point between the free end  139   a  and the union end  139   b  and generally parallel to the longitudinal coupling axis. The narrow slit is  137 ,  138  preferably an undulating slit, such as slit  140 . Such a slit is useful for gripping tape, such as caution tape, or signs. The slit is less than ¼-inch, and preferably less than ⅛-inch, and more preferably no greater than 1/16-inch in width and resilient (i.e., able to be spread open and returning to undeformed position when relaxed). 
         [0094]    In another configuration, the union end  139   b  of a first coupling sleeve mates with the first end  106  of the first mast and the union end  139   b  of a second coupling sleeve mates with the first end  107  of the second mast. In this configuration, a tape may extend from at least one of the undulating slits  137 ,  138  of the first coupling sleeve to at least one of the undulating slits  137 ,  138  of the second coupling sleeve. The undulating slits  137 ,  138  grip the tape. 
         [0095]    In another configuration, the free end  139   a  of each coupling sleeve  135  is sized to receive a second end  107  of each mast in alignment with the longitudinal coupling axis, as conceptually shown in  FIG. 10 . 
         [0096]    In another embodiment, additional masts, including a fourth mast and a fifth mast may be provided. In such an embodiment, the union end  139   b  of the first coupling sleeve may mate with the first end of the first mast, and the union end  139   b  of the second coupling sleeve may mate with the first end of the second mast, and the second end of the fourth mast may be received in the free end of the first coupling sleeve, with the fourth mast and the first mast being in axial alignment. The second end of the fifth mast may be received in the free end  139   a  of the second coupling sleeve, with the fifth mast and the second mast being in axial alignment and generally parallel to the fourth mast and the first mast. 
         [0097]    In another embodiment, an additional mast, i.e., a fourth mast, and an additional coupling sleeve, i.e., a third coupling sleeve, are provided. In this embodiment, the union end  139   b  of the first coupling sleeve mates with the first end of the first mast, and the union end  139   b  of the second coupling sleeve mates with the first end of the second mast, and the union end  139   b  of the third coupling sleeve mates with the first end of the third mast. The second end of the fourth mast is received in the free end  139   a  of the third coupling sleeve. The fourth mast and the third mast may be in axial alignment. The slot of the first coupling sleeve receives the first end of the third mast. The slot of the second coupling sleeve receives the second end of the fourth mast. 
         [0098]    With reference to  FIG. 27 , a base  110  may be provided to engage an end  107  of a vertically oriented mast in a vertical orientation. One embodiment may include a first base and a second base. Each base  110  may include a broad base having a base length that is at least three times the outer diameter of each mast, and a base width that is at least three times the outer diameter of each mast, and a base thickness that is at least as great as a distance from the second end of each mast to the second key slot of each mast (e.g., at least an inch thick). The base  110  includes a generally central mortise (i.e., socket)  112  that is shaped and sized to securely receive and frictionally engage the engaged end  107  of each mast. The central mortise  112  may include a collar  114  with a base sleeve  111  having a non-circular outer circumference shape. The base sleeve  111  may be received securely in a central aperture (mortise  112 ) in the base. The engaged end of the first mast may be received in the central mortise (e.g., in base sleeve of the central mortise) of the first base. The engaged end of the second mast may be received in the central mortise (e.g., in base sleeve of the central mortise) of the second base. 
         [0099]    Masts may be equipped with reflectors, such as retro-reflective sleeves  115 , as conceptually illustrated in  FIGS. 1-4 . Each retro-reflective sleeve  115  includes a plurality of adjoining panels (e.g., 3) defining an interior channel bound by a plurality of exterior planar surfaces (e.g., 3). Each exterior planar surface includes a retro-reflective element. The interior channel is sized to receive each mast. Each mast includes a midpoint between the first end and the second end of the mast. The first retro-reflective sleeve receives a portion of the first mast, between the first end and the midpoint of the first mast, and is secured to the received portion of the first mast with an attachment  120  (e.g., one or more mechanical attachments such as a rivet, nut and bolt, screw, snap-fit coupling or the like). 
         [0100]    In another embodiment, a top mast with a rounded free  315  end  139   a  is provided for supporting a tarp or other cover without puncturing it, as illustrated in  FIG. 20 . An exemplary top mast includes a mast with a hemispherical cap  315  attached to the first end. The second end of the top mast is received in the free end  139   a  of the first coupling sleeve  135 . 
         [0101]    Referring now to  FIGS. 28 through 38 , dimensioned components are illustrated. The dimensions are provided as nonlimiting examples. The dimensions are in inches. 
         [0102]      FIG. 28  conceptually illustrates a dimensioned mast  105  for a modular barrier according to principles of the invention. In this embodiment, the mast  105  does not include key slots  125 .  FIG. 29  conceptually illustrates another dimensioned mast  105  for a modular barrier according to principles of the invention. In this embodiment, the mast includes key slots  125 . 
         [0103]      FIGS. 30-32  provide plan and side views of an exemplary coupling sleeve  135 . In this embodiment the sleeve  135  includes semicircular slots  136  formed in each end of the sleeve  135 . The slots  136  are oriented orthogonal to each other. Undulating slits  138  are formed in one end. This coupling sleeve  135  may be used with or without a mast. By way of example, each slot may be used to couple a mast. Thus, the sleeve may join two masts together, orthogonally. 
         [0104]      FIGS. 33 and 34  provide plan and side views of a hexagonal collar  116  with a cylindrical opening in which the end of a mast is received. The hexagonal collar  116  plugs into a corresponding slot in the base  110 , which may be a solid base. 
         [0105]      FIGS. 35 and 36  provides front and side views of an exemplary coupling bolt  130  for a modular barrier according to principles of the invention. The space (0.875 inches) is about equal to the thickness of a wall of an exemplary mast  105 . Thus, an engaged edge of a key slot  125  snaps into the space (0.875 inches) and is securely held. 
         [0106]      FIGS. 37 and 38  provide dimensioned side views of an exemplary coupling sleeve  135  with one slot  136  formed in a free end. Unlike the embodiment of  FIGS. 30-32 , this embodiment includes one slot  136 . 
         [0107]    With reference to  FIG. 39 , a stiffener  605  may be inserted in an end  106  of hollow tube  105 . The stiffener  605  enhances rigidity of the hollow tube  105  in the areas of key slots  126   a, b , where removed material to form key slots compromises rigidity. A nonlimiting example of a stiffener is a dumbbell shaped insert  605  having concentric top and bottom ends  610 ,  615  connected by a concentric shaft  620 . The top and bottom ends  610 ,  615  have an outer diameter that is about equal to the inner diameter of the tube  105 . The shaft  620  has a smaller diameter to allow connections to be made through key slots  126   a, b.  The length of the shaft  620  is greater than the height of the first aperture portion  128  of the key slots  126   a, b.  The stiffener may be hollow or solid and comprised of any suitable material including substantially rigid plastics, wood or metal. Shapes other than a dumbbell may be utilized without departing from the scope of the invention. 
         [0108]    While an exemplary embodiment of the invention has been described, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention. With respect to the above description then, it is to be realized that the optimum relationships for the components and steps of the invention, including variations in order, form, content, function and manner of operation, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. The above description and drawings are illustrative of modifications that can be made without departing from the present invention, the scope of which is to be limited only by the following claims. Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents are intended to fall within the scope of the invention as claimed.
A kit contains mast modules that may be erected and connected in a variety of configurations to provide a barrier to accomplish any one or more of the following: guide traffic, protect and rope off an accident or crime scene, warn pedestrians and motorists of dangerous conditions, and shelter an area and/or first responders from sun and precipitation. Masts, coupling sleeves, coupling slots, slits and bases are interconnected to form a barrier.