ALEXANDRIA, Va., Aug. 25 -- United States Patent no. 12,716,474, issued on Aug. 25, was assigned to CHUAN HONG PRECISION TOOL MANUFACTURING Co. LTD. (Kaohsiung City, Taiwan).
"Planetary roller screw" was invented by San-Kuei Wu (Kaohsiung City, Taiwan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A planetary roller screw adapted for solving insufficient structural strength of the conventional planetary roller screw while proceeding with precise motion control is disclosed. The planetary roller screw includes a main screw having a first external thread, a nut having an internal thread, and a planetary assembly having rollers. Each roller includes a second external thread. Helix directions of the first extern...