ALEXANDRIA, Va., Sept. 17 -- United States Patent no. 12,416,226, issued on Sept. 16, was assigned to MITSUBISHI HEAVY INDUSTRIES LTD. (Tokyo).
"Crude oil extraction pump" was invented by Shuhei Sasaki (Tokyo) and Kimihiko Mitsuda (Tokyo).
According to the abstract* released by the U.S. Patent & Trademark Office: "A crude oil extraction pump includes: a production pipe having a tubular shape along an axis extending in a vertical direction; a pump rotor extending in a direction of the axis inside the production pipe; and a pump stator which is provided between the production pipe and the pump rotor to surround the pump rotor, wherein the pump rotor includes a plurality of pump shafts which are sequentially connected in the direction of the...