The present invention relates to portable enclosures, and in particular to a roll-formed frame arrangement therefor.
Portable closures or shelters, such as those disclosed in U.S. Pat. Nos. 3,335,535 and 3,952,463 (which are incorporated by reference herein) have become increasingly popular in recent years. Such structures typically comprise a series of screened wall panels, which are interconnected along their upstanding edges by flexible hinges. The wall panels are arranged in a closed polygon configuration, and support a dome-shaped, fabric roof. A door is provided in the structure to access the interior, and solid or opague panels can be installed over the screens to keep out gentle rain, wind, insects, etc, as well as to provide privacy.
The frames for the wall panels are generally constructed from extruded aluminum, with channels disposed along the side edges in which an I-shaped flexible hinge is mounted. The extruded frames require a relatively thick sidewall, in the nature of 0.045 inches, thereby resulting in high material costs, as well as expensive transportation and storage. The flanges or beads along the side edges of the flexible hinge are rectangular, and are typically fitted rather tightly into the mating frame channels, so as to form a reasonably weathertight seal therebetween. Since the flexible hinges are rather long, the assembly of the hinges into the frame channels by pulling the hinge beads therealong is a difficult task which can easily result in damage to the flexible hinges.
Retainers are used at the ends of each of the wall panels to hold the fastening cables in position. Heretofore, the legs of the retainer were manually compressed, and then inserted into the frame end. Wind and other forces acting on the roof and wall panels of the shelter are transmitted to the cables, and pull outwardly on the retainers. Prior to the present invention, separate left and right hand retainers were required to assemble the shelter, and the same had a tendency to inadvertently unlock from the frame when the shelter was exposed to gusts of wind, or other similar extreme forces.