This invention relates generally to an apparatus for attachment to the bed or frame of a truck for extending and retracting a flexible cover sheet over a container positioned on the truck bed in order that the contents of the container will not spill out or blow away during transport of the truck hauling the container. More specifically, this invention relates to an apparatus for extending and retracting a flexible cover sheet over open containers of various sizes which may at different times be positioned for hauling garbage and the like on the truck bed.
As is well understood in this art, it is advantageous for the truck and its bed or frame to be Capable of hauling various size containers for transporting garbage and the like. These containers can often range in size from about 20 cubic yards to about 40 cubic yards, that is from about 21 feet long .times.33/4 feet high to about 22 feet long .times.73/4 feet high, respectively. Therefore, it would be an advantage to have an apparatus which could be capable of covering such various size containers with a container cover. Also, it is often advantageous in either extending or retracting the container cover over the container to maintain as low a clearance as possible in order to minimize or prevent damage to the cover in the case of winds or other objects exerting high forces on the cover during its covering motion.
Within the prior art, U.S. Pat. No. 4,981,317 discloses an apparatus wherein the spool is mounted for vertical movement so that containers having different heights may be properly closed. There is no disclosure within this patent of the capability of closing containers of different lengths or closing the containers with minimal clearance of the cover sheet as it moves across the container. U.S. Pat. No. 3,868,142 discloses an apparatus provided with support means, with vertical and horizontal, which are capable of covering a container of various heights and lengths. There is no disclosure within the patent of closing the containers with minimal clearance of the cover sheet as it moves across the container. U.S. Pat. No. 4,874,196 discloses an apparatus provided with telescopic arms which are capable of carrying a cover sheet across the container in a low trajectory resulting in minimal clearance of the container. There is no disclosure within the patent of closing containers of various sizes, that is, various heights and various lengths.
Therefore, it would represent an advancement in the art to provide an apparatus for attachment to the bed of a truck for moving a cover sheet over an open container positioned thereon with the apparatus capable of covering containers of various size heights or lengths and with, if desired, minimal clearance over the container; especially if such an apparatus has few structural members required for operation and is provided with structural members capable of achieving maximum flexibility of operation.