ALEXANDRIA, Va., Dec. 31 -- United States Patent no. 12,509,933, issued on Dec. 30, was assigned to PIOLAX INC. (Kanagawa, Japan).
"Damper device" was invented by Shogo Kurihara (Kanagawa, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A damper device includes: a cylinder having a vent hole and a valve seat; and a piston. An elastically deformable valve body abuts against the valve seat before and when the piston moves in a damper braking direction. The valve seat is formed with a vent groove. A protrusion amount of an inclined surface gradually decreases from a side of an outer periphery of the valve seat toward the vent hole. The vent groove includes a first groove that extends from an outer peripher...