ALEXANDRIA, Va., June 17 -- United States Patent no. 12,311,377, issued on May 27, was assigned to Eom Ji Choi (Gyeongsangbuk-do, South Korea).
"Hydraulic breaker without back head" was invented by Eom Ji Choi (Gyeongsangbuk-do, South Korea) and Seong Gyu Choi (Gyeongsangbuk-do, South Korea).
According to the abstract* released by the U.S. Patent & Trademark Office: "A hydraulic breaker without a back head, includes a main control valve, to which fluid is supplied from the outside of the polyhedron, and accommodating a pilot valve for controlling the main control valve, in the interior space of the polyhedron, and in which impact force is obtained by double-acting cylinders, operated by the main control valve, moving modules that are conn...