Automatic swimming pool skimmer

Claim 1

A fluid skimmer, comprising a pair of cylinders having different diameters, one of said cylinders having a closed bottom and an open top, the other of said cylinders having both ends open, a tapered membrane connected between the open end of one of said cylinders and the open bottom end of the other of said cylinders forming a watertight fit with said cylinders and allowing said cylinders to slidably overlap with each other, a collar attached to the outer surface of said other cylinder near the upper end thereof, and a pipe extending below the level of a body of fluid and connected at the bottom of said pipe to said one of said cylinders, said other of said cylinders being positioned to overlap with the top portion of said one of said cylinders, said one of said cylinders being held at a uniform depth above the ground level of the body of fluid without regard to variations in the surface level of the body of fluid, the fluid pressure forcing said membrane to roll in one direction thereby moving said other of said cylinders in the same direction relative to the stationary said one of said cylinders, and said collar forcing said other of said cylinders in a direction opposite that produced by fluid pressure for keeping the upper open end of said other of said cylinders just below the surface level of the fluid body, the counterbalancing forces of the collar and the fluid pressure on said membrane in conjunction with the slidable connection between said cylinders allow said other of said cylinders to move up and down in the alternative in relation to said one of said cylinders for automatically adjusting the top opening of said other of said cylinders to a position just below the surface level of a body of fluid as it varies in depth, and said pipe allowing the skimmed fluid to be pumped out of said cylinders.