ALEXANDRIA, Va., Aug. 20 -- United States Patent no. 12,393,157, issued on Aug. 19, was assigned to Hewlett-Packard Development Co. LP (Spring, Texas).
"Rotational force transmission structure" was invented by Seungchan Park (Suwon, South Korea), Junhui Kim (Suwon, South Korea) and Youngkwang Shin (Suwon, South Korea).
According to the abstract* released by the U.S. Patent & Trademark Office: "A cartridge unit detachable from a main body of an image forming device includes: a rotation member; a driven coupler arranged at one end portion of the rotation member in an axial direction of the rotation member; and a coil spring arranged to be expandable and compressible in the axial direction, a first end portion of the coil spring being fixed ...