ALEXANDRIA, Va., Jan. 20 -- United States Patent no. 12,528,679, issued on Jan. 20, was assigned to NINGBO LIANDA WINCH Co. LTD. (Ningbo, China).
"Hyraulic jack" was invented by Xiaojun Cui (Ningbo, China).
According to the abstract* released by the U.S. Patent & Trademark Office: "A hydraulic jack is provided which comprises a piston cylinder, a piston rod, an oil passage switching valve and an internal cylinder. The oil passage switching valve is provided with an oil outlet; a one-way valve assembly preventing the backflow of the oil outlet passage is disposed between the first oil inlet passage and the oil outlet passage; a return oil inlet passage is disposed at the bottom of the piston head; a return oil chamber in communication with...