A-frame barricade

Abstract

A pair of A-frame members of molded plastic support an elongated beam extending through openings in apex portions thereof. Pockets are provided in the outsides of two legs of each A-frame member into which elongated weight cartridges are placed to be securely held to the legs. The legs and pockets are so formed that with a low volume and weight, a high strength and rigidity of the legs is achieved, a substantial contribution being made by the weight cartridges. The weights of the cartridges are used to resist tilting movement of the barricade and to achieve stability with a high degree of efficiency. The weight cartridges are preferably blow-molded plastic tubes filed with slag or sand and most preferably are interchangeable with cartridges currently in use in other applications. For additional stability, the legs of each A-frame member may be secured to an elongated member, to a plastic tube mounted there-between and / or to a blow-molded panel that is adapted to be filled with a weighty material and face in a longitudinal direction. Also, for additional strength and stability, elongated beams may be hung on lower portions of legs of the pair of A-frame members.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]Applicant claims the priority benefit of Provisional Application No. 60 / 937,777 filed Jun. 29, 2007 and entitled “A-FRAME BARRICADE”.[0002]The invention disclosed herein is not the result of any federally sponsored research or development activities.BACKGROUND OF THE INVENTION[0003]Barricade structures of the prior art include saw-horse and A-frame types of structures. Saw-horse structures typically include two units that are pivotally connected for movement between a folded condition against each other and an operative condition in inverted V-relation. In an early type of saw-horse structure, many of which are still in current use, each unit is in the form of a subassembly with wood panels secured to a pair of metal legs with bolts connecting the legs to form the pivotal connection. The Nunn U.S. Pat. No. 3,015,804 issued Jan. 2, 1962 shows a barricade including spaced apart leg units each consisting of a pair of hingedly connected legs a...

AI Technical Summary

Benefits of technology

[0012]In accordance with the invention, recesses are formed in the outsides of legs of A-frame members to provide pockets into which elongated weight cartridges are placed to be securely held to the leg portions. Preferably, each cartridge engages a rear wall of a leg, an outer wall of the leg and an intermediate wall spaced outwardly from an inner wall of the leg. The cartridge acts in compression between the outer wall and the intermediate wall to oppose bending of the leg. For additional strength and rigidly, angularly extending walls are provided the intermediate wall and the inner wall, also between outer and inner walls above the weight cartridge. The weights of the cartridges are used to resist tilting movement of the barricade and to achieve stability with a high degree of efficiency. The distance between a fulcrum point at the lower end of each leg portion and a vertical line through the center of gravity of a weight cartridge in the opposite leg portion is a high fraction of the distance between the lower ends of the leg portions. Means are provided for additional stability when necessary or desired, including means for securing elongated members to lower portions of the legs and means for mounting plastic tubes between lower portions of the legs of each A-frame member. The weight cartridges are preferably blow-molded plastic tubes filed with slag or sand and most preferably are interchangeable with those usable in the aforementioned saw horse type of structure made by Cortina Tool & Molding Co. Such weight cartridges have high specific gravity while being relatively inexpensive and they have a size and shape which are such that they can be compactly stored when not in use and can be reusable for any desired purpose.

[0013]Further aspects of the invention relate to observation and study of the effects of winds on A-frame barricades. The addition of the aforementioned weight cartridges substantially reduces the effect of winds as to tipping over and movement of the barricades. However, even with weight cartridges and / or other ballast, gusty conditions can cause a barricade to walk along as first one corner and then another is lifted. This phenomenon can occur with a barricade in which a single beam extends through and is supported by openings in apex portions of a pair of A-frame members. It has been observed that it involves bending of the barricade at the middle of the single beam and that the single beam has very low moment of inertia about a vertical axis. In accordance with the invention, two additional beams are supported from lower leg portions of the pair of A-frame members thereby greatly increasing the moment of inertia about a vertical axis and thereby decreasing bending. Each of the two additional beams is at an angle to the vertical, the same angle as that of the supporting leg, to have by itself an increased moment of inertia about a vertical axis and thereby resist bending The angular dispositions of the two additional beams may also result in development of a downward force coming from a side wind in either direction. In accordance with further features, each of the legs includes hook means projecting short distances from the outsides thereof for hanging thereon of opposite ends of the additional beams. Each hook means includes a hook portion turned upwardly to engage behind a downwardly turned end of a flange portion of a beam. In addition, each hook means preferably includes a hook portion turned downwardly to engage behind an upwardly turned lower flange portion of a beam.

[0014]Another feature of the invention is in the provision of a panel which can be secured to each A-frame member to face in a longitudinal direction and to carry warning indicia and / or colors. The panel is preferably blow-molded so as to be hollow and is adapted to be filled with liquid or solid materials to add addition weight and stability.

Problems solved by technology

The addition of the aforementioned weight cartridges substantially reduces the effect of winds as to tipping over and movement of the barricades.

However, even with weight cartridges and / or other ballast, gusty conditions can cause a barricade to walk along as first one corner and then another is lifted.

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