ALEXANDRIA, Va., Feb. 3 -- United States Patent no. 12,539,943, issued on Feb. 3.
"Gravity buoy" was invented by Robert J. Cavanagh Jr. (Lincoln, R.I.).
According to the abstract* released by the U.S. Patent & Trademark Office: "The gravity buoy includes a can float that is visible above the waterline and provides the buoyancy for the device. A pulley assembly permits a tether under constant tension to pass easily through a point near the bottom of the can float, thus creating a pull point. A tension weight provides the downward force that puts the tether under constant tension so that the can float maintains its location above the anchor, and helps keep the can float vertical in the water along with concrete ballast inside the bottom of ...