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FIELD OF THE INVENTION 
     This invention relates to barrier devices for vehicular traffic control, soil erosion containment, impact attenuation and the like which can be interconnected with one another to define a barrier wall structure, and, more particularly, to an end connector for barrier devices which allows them to articulate relative to one another through an angle of about 22.5° in both the clockwise and counterclockwise directions when arranged in an interconnected line forming a barrier wall. 
     BACKGROUND OF THE INVENTION 
     A variety of different devices have been developed for absorbing the kinetic energy resulting from impact with a moving vehicle, and for the containment of forces exerted by soil or water. Highway barriers and channelizers, for example, are intended to provide a continuous wall or barrier along the center line or shoulder of a highway when laid end-to-end to absorb grazing blows from moving vehicles. One commonly used highway barrier is formed of pre-cast reinforced concrete, and is known as the “Jersey” style barrier. Highway barriers of this type have a relatively wide base resting on the pavement or shoulder of the highway, opposed side walls and opposed end walls. The side walls consist of a “curb reveal” extending vertically upwardly from the base a short distance, a vertically extending top portion connected to the top wall of the barrier and an angled portion between the curb reveal and the vertical top portion. This design is intended to contact and redirect the wheels of a vehicle in a direction toward the lane of traffic in which the vehicle was originally traveling, instead of the lane of opposing traffic. See, for example, U.S. Pat. No. 4,059,362. 
     One problem with the Jersey-style highway barriers described above is the weight of reinforced concrete. A concrete barrier having a typical length of twelve feet weighs about 2,800-3,200 pounds, and requires special equipment to load, unload and handle on site. It has been estimated that for some road repairs, up to 40 percent of the total cost is expended on acquiring, delivering and handling concrete barriers. Additionally, concrete barriers have little or no ability to absorb shock upon impact, and have a high friction factor. This increases the damage to vehicles which collide with such barriers, and can lead to serious injuries to passengers of the vehicle. 
     In an effort to reduce weight, facilitate handling and shipment, and provide improved absorption of vehicle impact forces, highway barriers have been designed which are formed of a hollow plastic container filled with water, sand or other ballast material such as disclosed in U.S. Pat. Nos. 4,681,302, 4,773,629, 4,946,306, 5,123,773 and 5,882,140. For example, the &#39;302 patent discloses a barrier comprising a housing having a top wall, bottom wall, opposed side walls and opposed end walls interconnected to form a hollow interior which is filled with water. The ends of each barrier couple to an adjacent barrier to form a continuous wall. The container structure is preferably formed of a resilient, plastic material which is deformable upon impact and capable of resuming its original shape after being struck. 
     The &#39;629, &#39;306, &#39;773 and &#39;140 patents noted above represent advances in deformable highway barrier designs. The first two patents disclose barriers which comprise a longitudinally extending housing made of semi-rigid plastic which is self-supporting, and has a predetermined shape which is maintained when filled with water, sand or other ballast material. Such devices are connected end-to-end by a key insertable within grooves formed in the end walls of adjacent barriers. Interconnected fill openings are provided which permit adjacent barriers to be filled with water or other ballast material when laid end-to-end. 
     The &#39;773 and &#39;140 patents disclose further improvements in barrier devices including side walls formed with higher curb reveals, a horizontally extending step and vertical indentations in order to assist in maintaining the structural integrity of the container, and internal baffles for dampening movement of water or other ballast material within the container interior. Interlocking male and female coupling elements are formed on the opposite end walls of each barrier to facilitate connection of adjacent barriers end-to-end. Additionally, channels or openings are formed in the barriers from one side wall to the other to permit the insertion of the tines of a fork lift truck therein for easy loading, unloading and handling of the barriers. 
     One problem with barrier devices of the type described above is that the coupling elements which connect one barrier device to an adjacent one permit limited pivotal movement. While a gradual curve along a barrier wall formed by a number of interconnected barrier devices may be obtained, the amount of articulation between adjacent barriers is limited to a few degrees. Consequently, such barrier devices may not be used on roadways or other applications with sharper curves. 
     SUMMARY OF THE INVENTION 
     This invention is directed to an end connector for a barrier or channelizer device which permits articulation of one barrier device through a relatively large angle with respect to an adjacent barrier device within a barrier wall, so that a barrier wall may be formed having a significantly curved shape. 
     The barrier device of this invention comprises a housing having a top wall, a bottom wall, opposed end walls and opposed side walls interconnected to form a hollow interior adapted to be at least partially filled with a ballast material. In the presently preferred embodiment, the end connector of each barrier device includes a first coupling element on one end wall and a second coupling element on the opposite end wall, both of which extend from the top wall of the barrier device to its bottom wall. The first coupling element has a generally cylindrical-shaped inner cavity, defined by a curved surface on the end wall, a portion of which is open. An arm extends from opposite sides of the opening in the inner cavity. Each arm forms a stop along its inner surface, and a convex pivot surface along its outer surface. The two stops are spaced approximately 45° from one another. 
     The second coupling element on the opposite end wall of each barrier device includes a neck section protruding outwardly from a concave pivot surface formed on such opposite end wall between the top and bottom walls of the barrier device. The neck section is connected to a cylindrical-shaped pivot pin. In forming a barrier wall with the barrier devices of this invention, the pivot pin of the second coupling element of one barrier device is inserted into the inner cavity of the first coupling element of an adjacent barrier. The pivot pin is captured within the inner cavity, and the neck portion of the second coupling element extends between the two arms of the first coupling element. Because the two arms of the first coupling element are spaced about 45° apart, the barrier with the second coupling element can pivot throughout essentially the same 45° angle relative to the adjacent barrier, e.g. approximately 22.5° in both the clockwise and counterclockwise direction. This permits a barrier wall to be formed having a substantial curve, compared to that permitted in prior barrier device designs, allowing the barrier devices herein to be used on most curved roadways and similar applications. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The structure, operation and advantages of the presently preferred embodiment of this invention will become further apparent upon consideration of the following description, taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a perspective view of a barrier device having the end connector of this invention; 
         FIG. 2  is a plan view of the barrier device shown in  FIG. 1 ; 
         FIG. 3  is a partial plan view of one barrier device connected to an adjacent barrier device, with the two barrier devices aligning with one another; and 
         FIG. 4  is a view similar to  FIG. 3  except with the two barrier devices pivoted relative to one another. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the Figs., the barrier device  10  of this invention comprises a top wall  12 , a bottom wall  14 , opposed end walls  16 ,  18 , and, opposed side walls  20 ,  22  which are interconnected to collectively define a hollow interior. A number of barrier devices  10  may be arranged end-to-end to form an essentially continuous wall. Two barrier devices  10 ,  10 ′ are shown in  FIGS. 3 and 4  which are identical in structure and function, and therefore the same reference numbers are used to identify like structures with the addition of a “′” to the numbers associated with the barrier  10 ′. 
     In the presently preferred embodiment, each of the walls  12 - 22  are formed of a semi-rigid plastic material chosen from the group consisting of low density polyethylene, acrylonitrile or butadiene styrene, high impact styrene, polycarbonates and the like. These plastic materials are all inherently tough and exhibit good energy absorption characteristics. They will also deform and elongate, but will not fail in a brittle manner at energy inputs which cause other materials to undergo brittle failure. The surfaces of these types of plastic materials are inherently smoother than materials from which other barriers are typically constructed, therefore creating less friction and reducing the likelihood of serious abrasion injuries to vehicles and/or passengers who may come into contact therewith. Additionally, materials of this type are unaffected by weather and have excellent basic resistance to weathering, leaching and biodegradation. Additives such as ultraviolet inhibitors can be combined with such plastic materials making them further resistant to the effects of weather. They also retain their mechanical and chemical properties at low ambient temperatures. 
     When using the barrier device  10  of this invention as a highway barrier, the hollow interior is preferably filled with a “ballast” material such as water or other liquid, or a flowable solid material such as sand, concrete and the like. For this purpose, the walls  12 - 22  of barrier device  10  have a thickness in the range of about one-eighth inch to one inch so as to perform satisfactorily in service. The barrier device  10  is preferably in the range of about six to eight feet in length, and, at the wall thickness noted above, has a weight when empty of about 20 to 140 lbs. When filled with a liquid such as water, the overall weight of the barrier is in the range of about 150 to 2,200 lbs. Flowable solid material such as sand and the like increase the weight of barrier  10  further. 
     The side walls  20  and  22  each include a substantially vertically oriented curb reveal  26  located between the bottom wall  14  and a horizontally extending ledge or step  28 . Extending upwardly at an acute angle from the step  28  is an intermediate section  30  which terminates at the top wall  12 . The top wall  12  of barrier  10  is formed with a pair of fill holes  32 , preferably having a diameter in the range of about 3-4 inches, through which ballast material may be poured into the hollow interior of the barrier  10 . In the presently preferred embodiment, a number of stabilizers  34  are integrally formed in the intermediate section  30 , at regularly spaced intervals between the end walls  16 ,  18 . Openings  36  extend through the barrier device  10 , between the side walls  20  and  22 , which are sized to receive the tines of a fork lift truck in order to move the barrier device  10  from place to place. A stabilizing plate  38  may be connected to the curb reveal  26  of each side wall  20  and  22  to enhance the lateral stability of the barrier device  10 . The plates  38  may be formed with one or more holes  40  through which stakes or bolts (not shown) may be inserted and driven into the ground, highway or other surface to provide additional stability. 
     In the presently preferred embodiment, the end wall  16  is formed with a first coupling element  42  and the end wall  18  is formed with a second coupling element  44  which permit articulation of one barrier device  10  relative to a second barrier device  10 ′ as discussed below. The first and second coupling elements  42  and  44  extend from the top wall  12  to the bottom wall  14  of the barrier device  10 . The first coupling element  42  comprises an inner cavity  46  defined by an arcuate surface of the end wall  16  having the general shape of a portion of a cylinder. The inner cavity  46  is formed with an outwardly facing opening  48  which is bounded on one side by a first arm  50  and on the opposite side by a second arm  52 . The first arm  50  includes an angled inner surface forming a stop  54 , and an outer portion defining a convex pivot surface  56 . The second arm  52  has the same construction, with a stop  58  and convex pivot surface  60 . As best seen in  FIG. 2 , the surfaces forming the stops  54  and  58  of the arms  50  and  52  are spaced from one another and oriented at an angle relative to the longitudinal axis  62  of the barrier device  10 . The angle formed by each stop  54  and  58  with the longitudinal axis  62  is preferably on the order of about 22.5° thus defining an overall angle between the stops  54  and  58  of about 45°. As such, the angular extent of the inner cavity  46  is approximately 315°. 
     The second coupling element  44  formed on the end wall  18  comprises a concave surface  64  extending from the top wall  12  to the bottom wall  14  of the barrier device  10 , and between its side walls  20  and  22 . A thin, generally rectangular-shaped neck section  66  protrudes outwardly from the concave surface  64 , along its entire length. The neck section  66  is connected to a generally cylindrical-shaped pivot pin  68 . 
     Referring now to  FIGS. 3 and 4 , in order to form a barrier wall  70  of a number of barrier devices  10 ,  10 ′, the inner cavity  46  of the first coupling element  42  receives the pivot pin  68 ′ of the second coupling element  44 ′ of an adjacent barrier device  10 ′ such that the neck portion  66 ′ of the second coupling element  44 ′ extends between the first and second arms  50 ,  52  of the first coupling element  42 . The pivot pin  68 ′ has a larger diameter than the width of the opening  48  between the arms  50  and  52  of first coupling element  42 , and must be inserted into the inner cavity  46  from the top wall  12  toward the bottom wall  14 , or vice versa. This ensures that the two barrier devices  10  and  10 ′, once connected, do not disengage from one another. 
     As depicted in  FIG. 3 , when adjacent barriers  10  and  10 ′ are connected together, the convex pivot surfaces  56  and  60  of respective arms  50  and  52  of the first coupling element  42  bear against the concave surface  64 ′ of the second coupling element  44 ′. The neck section  66 ′ of the second coupling element  44 ′ has sufficient length so that it extends somewhat beyond the opening  48  of the inner cavity  46 . The barriers  10  and  10 ′ are pivotal relative to one another along their cooperating pivot surfaces  56 ,  60  and  64 ′, respectively, in either the clockwise or counterclockwise direction, until the neck section  66 ′ of the second coupling element  44 ′ of barrier device  10 ′ engages the stop  54  or stop  58  of the first coupling element  42  of barrier device  10 . The barrier devices  10 ,  10 ′ may travel through an angle relative to one another of somewhat less than the 45° spacing between the stops  54 ′,  58 ′ due to the thickness of the neck section  66 , e.g. about 22.5° in both the clockwise and counterclockwise directions, but such extent of articulation is far superior than barrier devices currently commercially available. As a result, the overall barrier wall  70  formed by alternating barrier devices  10  and  10 ′ can assume a comparatively sharp curve when positioned along a roadway or the like. 
     While the invention has been described with reference to a preferred embodiment, it should be understood by those skilled in the art that various changes may be made and equivalents substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims.

Summary:
An end connector for a barrier device is provided which permits articulation of one barrier device through a relatively large angle with respect to an adjacent barrier device, so that a barrier wall may be formed of a plurality of barrier devices connected end-to-end having a significantly curved shape.