Scaffolding comprises horizontal scaffold members 1500 and vertical scaffold members 1000 connected into a frame structure. Generally, a complete frame is composed of rectangular scaffold structures joined together. Attached to, or resting on the horizontals of the scaffold frame structure, at particular heights, are scaffold planks used to create an elevated working surface. At times, a second elevated working surface may be needed that is connected to, but offset from, the scaffold frame structure. See
Two triangular frame members 900 (each considered a “knee-out frame member”) are attached to the scaffold frame at the same vertical height, but separated horizontally. This creates a knee-out frame structure to which scaffold planks may be supported or attached, to form the offset working platform. Vertical members 1000A may be attached at the edge of the knee-out platform, with horizontal members therebetween, to form a safety fence and provide a more safe working surface. Note that the knee-out frame member's far end 905 is not supported by a vertical scaffold member, allowing the knee-out platform to extend over structures without interference from the structure (such as a tank).
Modular scaffolding is a system scaffold having horizontal scaffold members and vertical scaffold members designed to be clipped or coupled together at a scaffold joint, to create a scaffold structure. A scaffold joint comprises a connector on the vertical scaffold member that is designed to couple or mate with a connector on a horizontal scaffold member, thereby joining together a horizontal and vertical scaffold member. One type of modular scaffold joint uses an end connector positioned on the end of a horizontal member, where the end connector has lip or hook sections. The lip sections are designed to engage or rest on cups or annuli rings positioned on a vertical scaffold member. One such joint is disclosed in U.S. Pat. No. 4,445,307, hereby incorporated by reference. A second type of latching connector is disclosed in U.S. Pat. Nos. 5,078,532 and 5,028,164, hereby incorporated by reference. A third type of latching mechanism is that disclosed in U.S. application Ser. No. 11/738,273, filed Apr. 20, 2007 (hereby incorporated by reference). And a fourth type of latching mechanism is disclosed in U.S. patent application Ser. No. 12/489,166 filed on Jun. 22, 2009, entitled “Scaffold end connector” (hereby incorporated by reference).
On each of these modular systems, the horizontal and vertical scaffold members are preferably constructed of hollow steel pipe, preferably galvanized pipe. A commonly used pipe is 1¾ inch diameter steel pipe, having ⅛ inch wall thickness.
As described, typically a knee-out frame member are constructed to create 3, 4, or 5 foot cantilevered trusses used to support a outlying platform. Extensions beyond 5 feet are possible, but difficult to assemble by hand as the triangular knee-out frame members are rigid structures that are bulky, hard to maneuver, and for modular scaffold section, very heavy. As such, they are difficult to attach to a scaffold frame by manual labor.
The preferred embodiment of the foldable knee-out scaffold frame member comprises two scaffold members (such as pipes), a first member 30, which will be the horizontal member when installed, and a second member 40, which will be the sloped bracing member or truss member) when installed. The two members 30 and 40 are pivotably joined at a pivot joint 50. Pivot joint 50, as shown, is two downward extending plates or fingers 51 positioned on opposing sides of first member 30, with an aligned opening through the two plates 51. Second member's 40 distal end is positioned between the two plates, and has an opening that aligns with those in the plates 51. A pivot pin is then inserted through the openings and fixed in place. See
Each member 30, 40 terminates in a scaffold frame connector 31 and 41, respectively. The connector may be any scaffold latch (a means for latching to a scaffold frame member) suitable for use in a modular scaffold system, or the connector may be a means for clamping to a scaffold frame member, such as the “U” clamp member 90 shown in
Additionally, the first frame member 30 may have an adjustable pivot point 51. For instance, the two plates 51 may be attached to a separate clamp, where the clamp is slidable along the first scaffold member 30 when the clamp is loose (not shown), but fixed in position with respect to the first scaffold member 31 when the clamp is tight (not shown). This arrangement allows the join location of the first and second members to be easily adjusted. For added flexibility, the first scaffold member 30 may be composed of two members 30A and 30B, with 30B slidably inserted into the member 30A (see
As shown in
The preferred method of attaching a foldable knee-out frame member to a scaffold frame is as follows. The first member's 30 scaffold end connector 31 is attached to the desired location on the scaffold frame. The first and second members 30 and 40 hang almost straight downward for the attached end connector 31. See
After two foldable knee-out sections are installed on the scaffold structure at substantially the same height, scaffold flooring, such as scaffold planks, may be supportedly positioned between the first and second foldable knee-out sections to create a working surface.
In transport, the foldable knee-out section may be folded into a compact structure (first member positioned adjacent the other) by folding (e.g. pivoting) about the pivot joint 50, as shown in
This application is a divisional of U.S. application Ser. No. 12/824,314, filed on Jun. 28, 2010, which application claimed the priority benefit of U.S. provisional application No. 61/227,250, filed on Jul. 21, 2009. the contents of both are hereby incorporated by reference.
Number | Date | Country | |
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61227250 | Jul 2009 | US |
Number | Date | Country | |
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Parent | 12824314 | Jun 2010 | US |
Child | 14066139 | US |