ALEXANDRIA, Va., Dec. 16 -- United States Patent no. 12,497,804, issued on Dec. 16.
"Chain lock" was invented by Cheng-Yu Tsai (Hemei Township, Taiwan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A chain lock comprises a lock body with a cylindrical shape and a chain connected to the lock body at one end and to a bolt at the other end. The lock body has two shells, with the second shell sleeved within the first shell. Inside the second shell, there is a lock core, a lock seat, and an installation seat. The lock seat and the chain are connected at opposite ends of the installation seat. An actuating element connects the lock core and the lock seat, allowing them to rotate simultaneously. The side wall of th...