Patent 11009313 was granted and assigned to Umarex Usa, Inc. on May, 2021 by the United States Patent and Trademark Office.
A valve system utilizes a main valve body with a restricted diameter conduit communicating between a propulsion chamber and rear cavity and a smaller venting valve mechanically actuated to open the rear cavity to atmosphere, thereby causing the main valve body to open to pass pressurized air in the propulsion chamber to an orifice to power a projectile.