ALEXANDRIA, Va., March 19 -- United States Patent no. 12,253,170, issued on March 18, was assigned to TSUBAKIMOTO CHAIN Co. (Osaka, Japan).
"Tensioner" was invented by Yuichiro Ishikawa (Osaka, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "An object of the present invention is to provide a tensioner with a simple structure that effectively maintains the oil pressure inside an oil pressure chamber at a correct level, while also making the machining and assembling processes less demanding. The tensioner includes a relief mechanism, which includes an orifice member that has an oil passage designed to form an orifice structure. The orifice member has a flat circular end wall part and a circumferential wal...