ALEXANDRIA, Va., Sept. 30 -- United States Patent no. 12,432,500, issued on Sept. 30, was assigned to FOSTER ELECTRIC COMPANY Ltd. (Tokyo).
"Speaker magnetic circuit and speaker driver" was invented by Yusuke Muta (Tokyo) and Haijiao Han (Tokyo).
According to the abstract* released by the U.S. Patent & Trademark Office: "The speaker magnetic circuit includes a yoke cover that is formed from a tubular magnetic body with a diaphragm attachable to an end portion on an axial direction one-side, a magnet arranged at an inside of the yoke cover, a volume adjusting member that is formed from a tubular non-magnetic body, that is provided between the yoke cover and the magnet, and that is formed with a first groove extending in the axial direction...