Average Co-Inventor Count = 2.46
ph-index = 3
The patent ph-index is calculated by counting the number of publications for which an author has been cited by other authors at least that same number of times.
Company Filing History:
1. Hitachi Metals, Ltd. (3 from 2,333 patents)
2. Alpine Electronics, Inc. (1 from 937 patents)
3. 501 Hitachi Metals, Ltd. (1 from 7 patents)
5 patents:
1. 5715324 - Speaker having magnetic circuit
2. 5370158 - Weft winder for weaving machine having magnets with different surface
3. 5096763 - Magnet article for attracting foreign matters in the stomach
4. 4670726 - Convergence device for electron beams in color picture tube
5. 4412104 - Rectangular magnetic circuit for speaker