ALEXANDRIA, Va., March 19 -- United States Patent no. RE50,337, issued on March 18.
"Hydraulic leveraged overhead door assembly" was invented by David A Crown (Waconia, Minn.) and Phillip A Crown (Lester Prairie, Minn.).
According to the abstract* released by the U.S. Patent & Trademark Office: "The present invention is a door assembly including a rectangular door frame, a bi-fold door pivotally mounted at the top of the rectangular door frame and at least one hydraulic cylinder assembly. The hydraulic cylinder assembly is pivotally secured by a first end to a cylinder support mounted on a back side of the door frame, and by a second lower end to a cylinder support secured to a back surface of a top panel of the bi-fold door. In the door ...