A-frame barricade
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.
Applicant claims the priority benefit of Provisional Application No. 60/937,777 filed Jun. 29, 2007 and entitled “A-FRAME BARRICADE”.
The invention disclosed herein is not the result of any federally sponsored research or development activities.
BACKGROUND OF THE INVENTIONBarricade 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 and connected at upper ends by a round rod and near their lower ends by cross pieces. The Look et al. U.S. Pat. No. 4,852,511 shows panels supported by a pair of legs joined by a cross-member and a flexible substantially closed container supported by the legs or cross-member and adapted to be filled with a liquid to add to weight and stability.
Many saw-horse structures have been used or proposed using components molded from plastic. The Stehle et al. U.S. Pat. No. 3,880,406 issued Apr. 29, 1975 discloses a plastic barricade in which units are pivotally connected by bolts after being formed with integral panels and legs. The units are formed by rotational casting to be hollow and can be filled with sand or other ballast to resist tipping over. The Glass U.S. Pat. No. 4,298,186 issued Nov. 3, 1981 discloses a barricade including a pair of identical members of hollow plastic that provide integral panels and legs. The members have hinge members located at upper corners thereof and configured to be connected together by bolts. At the lower ends, hollow sand bars are provided for receiving sand bags. The Kulp et al. U.S. Pat. No. 4,859,983 issued Aug. 22, 1989 shows a plastic barricade including lower rails which provide storage compartments for storing a ballast such as loose sand or a castable liquid plastic. The Cushman U.S. Pat. No. 5,544,614 issued Aug. 13, 1996 discloses a barricade assembly including panel units each having a pair of legs, one leg each unit having a pair of eyelet members, the other having a pair of hook members. The hook members of one panel unit can fit into the eyelet members of a second unit to secure two units together. The Glass et al. Patent No. 6,101 shows a plastic barricade having leg and panel units that are pivotally connected. Each unit includes first and second leg members and a plurality of panel members. The members are separately blow-molded and thereafter bolted together.
In a saw-horse barricade made by the Cortina Tool & Molding Co., replaceable panels are secured to two spaced pairs of hingedly connected legs. Elongated weight cartridges are optionally snapped into recesses formed in the insides of lower portions of the legs. The weight cartridges are blow-molded plastic tubes filed with slag or sand. Such weight cartridges can also be used for support on roadway surfaces of emergency warning devices, including triangularly shaped devices similar to that disclosed in my U.S. Pat. No. 6,178,676 issued Jan. 30, 2001.
In A-frame types of barricades, rails or beams have ends supported by two members each of which includes two legs extending angularly inwardly from spaced lower ends to meet at upper ends so as to be in the shape of the letter A. The Parker U.S. Pat. No. 3,089,682 issued May 14, 1963 provides an early disclosure of an A-frame barricade. A one-piece top member forms a rail or beam which is supported by a pair of oppositely disposed A-shaped legs. The top member and legs are disclosed as being formed of resilient hard rubber.
The Thomson et al. U.S. Pat. No. 4,943,035 issued Jul. 24, 1990 discloses a barricade with A-shaped members supporting the ends of an elongated hollow crossbar which includes elongated hollow inter-connecting sections.
The Giannelli U.S. Pat. No. 5,762,444 issued Jun. 9, 1998 discloses an A-frame barricade capable of being adjusted to a desired length. A pair of A-frames are connected by a transverse beam assembly which includes a pair of members arranged for relative slidable movement to be of adjustable length. Each A-frame includes an opening for receiving an end of the beam assembly and also includes a cross brace portion with an integral bracket providing a second opening which can receive the end of an auxiliary cross-beam. The auxiliary cross-beam is not shown but can be used to support one of more sand bags.
The Bartlett U.S. Pat. No. 5,794,923 issued Aug. 18, 1998 discloses a dressage area fence module including brackets formed of diverging legs having slots through which rails extend. Each slot provides rail coupling means to couple a rail to the bracket. Three rails are shown, two located on a front side and one on a back side.
In the Lund U.S. Pat. No. 6,705,796, issued to me on Mar. 16, 2004, I disclose versatile multi-function legs useable to form either saw-horse or A-frame types of barricades. A pair of the legs can be supported by A-frame members to provide vertical posts that have openings for receiving the ends of two lower beams and for receiving and supporting a third beam at a higher elevation. An additional pair of the legs can be secured to lower ends of the A-frame members to provide horizontal sand rails for receiving sand bags.
The Williamson U.S. Pat. No. 6,772,707 issued Aug. 10, 2004 discloses in
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.
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.
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.
This invention contemplates other objects, features and advantages which will become more fully apparent from the following detailed description taken in conjunction with the drawings.
In
In accordance with the invention, the legs 15 and 16 are formed with recesses which provide pockets for receiving two elongated weight cartridges 19 and 20. Through the force of gravity acting thereon, the cartridges 19 and 20 function to resist tilting movement of the members 11 and 12. Thus cartridge 19 in leg 15 develops a stabilizing torque equal to the product of its weight and the distance between a vertical line through its center of gravity and a fulcrum point at the lower end of the leg 16, that distance being a high fraction of the distance between the lower ends of the legs 15 and 16. In a similar fashion, the cartridge 20 develops a stabilizing torque operating in an opposite rotational direction about a fulcrum point at the lower end of the leg 15.
The member 12 is substantially identical to the member 11 and includes two legs 21 and 22 meeting at an apex portion 23 and an intermediate portion 24 like portion 18 of member 11. Legs 21 and 22 are formed with recesses that provide pockets for receiving two elongated weight cartridges 25 and 26. The connecting portions 18 and 24 of members 11 and 12 are formed with slots for receiving and supporting end portions of an elongated beam, not shown, which may be like the beam 14. As disclosed in aforementioned U.S. Pat. No. 6,705,796, when two beams are supported, a third beam may be supported at a higher elevation through the use of vertical posts that have openings for receiving the three beams.
As shown in
In many applications, the provision of the weight cartridges 19, 20, 25 and 26 will provide more than adequate stability. However, the provision of the weight cartridges does not preclude the use of additional means for stabilization. As shown in
The cartridge 19 is preferably a blow-molded tube filled with a material 45 which is heavy but relatively inexpensive. It is most preferably the same as cartridges which are available for other purposes, being in use for stabilizing of saw-horse barricades and the support of warning triangles on road surfaces.
The barricade 48 also differs from the barricade 10 in the addition of two panels 53 and 54 that are secured to the frame members 49 and 50. The panels 53 and 54 have planar surfaces that face in opposite longitudinal directions and that may have colors or carry indicia to provide warnings or directions. The weight of the panels 53 and 54 can also provide increased stability. Preferably, the panels are blow-molded to be hollow and can be filled with sand or other solid particulate material or with water or other liquid material.
To hang one end of the beam 52 on the leg 56, the leg 56 is formed with a hook portion 61 which is turned upwardly to engage behind a down-turned flange portion that extends along the length of the upper end of the beam 52. The leg 56 is also formed with a lower hook portion 62 which engages behind an upturned flange portion of that extends along the length of the lower end of the beam 52. As shown in
In
It will be understood that variations and modifications may be effected without departing from the spirit and scope of the invention.
Claims
1. A barricade comprising: an A-frame member for coacting with a like A-frame member to support ends of one or more elongated beams, said A-frame member including two legs that extend angularly upwardly and inwardly toward each other to meet at an apex portion, each of said legs being formed with a recess that provides a pocket for receiving an elongated weight cartridge.
2. A barricade as defined in claim 1, wherein each of said legs includes facing walls for engaging opposite side surfaces of a weight cartridge and a rear wall for engaging a rear surface of a weight cartridge.
3. A barricade as defined in claim 2 for use with weight cartridges that have central openings for mounting purposes, each of said legs including a post that extends forwardly from said rear wall thereof for extending through a central opening of a weight cartridge, and a washer for installation on the end of said post for holding a weight cartridge in place.
4. A barricade as defined in claim 2, wherein each of said legs includes an outer wall, an inner wall, and an intermediate wall between said outer and inner walls, said facing walls being provided by said intermediate wall and one of said outer and inner walls.
5. A barricade as defined in claim 4, each of said legs further including walls that extend angularly between said intermediate wall and said one of said outer and inner walls and also between said outer and inner walls above said pockets for additional strength and rigidity.
6. A barricade as defined in claim 1, a panel secured to said A-frame member to face in a longitudinal direction and to be highly visible for warning or informational purposes, said panel being hollow and being adapted to be filled with liquid or solid materials to add additional weight and stability.
7. A barricade as defined in claim 1, said A-frame member including an opening in said apex portion for coacting with a like opening of a like A-frame member to support opposite ends of one elongated beam, and each of said legs including hook means projecting from the outsides of lower end portions thereof for coacting with like means of a like A-frame member for hanging opposite ends of two additional elongated beams on the legs to provide increased stability and pedestrian barriers.
8. A barricade as defined in claim 7, wherein said A-frame member is usable in support of beams that include upper flange portions terminating in downwardly turned ends, each of hook means comprising a hook portion turned upwardly to engage behind a downwardly turned end of an upper flange portion of a beam.
9. A barricade as defined in claim 8, wherein said beams include lower flange portions terminating in upwardly turned ends, each of said hook means further comprising a lower hook portion turned downwardly to engage behind an upwardly turned end of a lower flange portion of a beam.
10. A barricade as defined in claim 7, a panel secured to said A-frame member to face in a longitudinal direction and to carry warning indicia or colors, said panel being hollow and being adapted to be filled with liquid or solid materials to add addition weight and stability.
11. A barricade comprising a pair of A-frame members for supporting opposite ends of one or more elongated beams, each of said A-frame members including two legs that extend angularly upwardly and inwardly toward each other to meet at an apex portion, an elongated weight cartridge for installation in a pocket formed in each of said legs, each of said legs including facing walls for engaging opposite side surfaces of a weight cartridge and a rear wall for engaging a rear surface of a weight cartridge.
12. A barricade as defined in claim 11, each of said weight cartridges having a central opening, and each of said legs having a post that extends forwardly from said real wall thereof for extending through said central opening of a weight cartridge, a washer for installation on the end of each of said posts for holding a weight cartridge in place.
13. A barricade as defined in claim 11, wherein each of said legs includes an outer wall, an inner wall, and an intermediate wall between said outer and inner walls, said facing walls being provided by said intermediate wall and one of said outer and inner walls.
14. A barricade as defined in claim 13, each of said legs further including walls that extend angularly between said intermediate wall and said one of said outer and inner walls and also between said outer and inner walls above said pockets for additional strength and rigidity.
15. A barricade comprising a pair of A-frame members for supporting opposite ends of one or more elongated beams, each of said A-frame members including two legs that extend angularly upwardly and inwardly toward each other to meet at an apex portion, said A-frame members including openings in said apex portions thereof for supporting opposite ends of one elongated beam, two additional beams supported on lower portions of said legs to be positioned at the same angles to the vertical as said legs and functioning to increase the moment of inertia of said barricade about a vertical axis and thereby reduce bending of said barricade in response to gusty side winds, said additional beams being otherwise operative to provide increased stability and also being usable to provide a pedestrian barricade.
16. A barricade as defined in claim 15, wherein and each of said legs includes hook means projecting from outsides of lower end portions thereof for hanging of opposite ends of said two additional elongated beams on said legs to provide increased stability and pedestrian barriers.
17. A barricade as defined in claim 16, wherein said beams include upper flange portions terminating in downwardly turned ends, each of hook means comprises a hook portion turned upwardly to engage behind a downwardly turned end of an upper flange portion of a beam.
18. A barricade as defined in claim 16, wherein said beams include lower flange portions terminating in upwardly turned ends, each of said hook means further comprising a hook portion turned downwardly to engage behind an upwardly turned lower flange portion of a beam.
Type: Application
Filed: Jun 30, 2008
Publication Date: Jan 15, 2009
Inventor: John Iver Lund (Chicago, IL)
Application Number: 12/215,758
International Classification: E01F 13/02 (20060101);