Retractable cover for ground opening

Abstract

A retractable cover mechanism for covering an open area, such as a swimming pool. The mechanism comprises a pair of parallel channels secured on a respective opposed side of an open area to be covered. A plurality of displaceable intermediate cylinders are provided in each of the channels between displaceable end cylinders. The intermediate cylinders are water-conducting and the end cylinder at a first common end of both channels is water-conducting. The end cylinders at a second common end of both channels have solid end walls which are non-water conducting. A first extensible conduit means is secured between facing ends of adjacent ones of the intermediate and end cylinders. Attachment means are secured to at least some of the cylinders and to a cover sheet to displaceably support the cover sheet between the pair of parallel channels. First and second conduit means are connectable to a source of water pressure. The second extensible conduit means is secured between outer end walls of the end cylinders and an associated one of the first and second conduit means whereby the source of water pressure is applicable against the outer end walls of one of the end cylinders at a common end of each of the channels. Valve means is further provided to evacuate the first and second conduit means.

Dependencies are inferred from the claim text.