Average Co-Inventor Count = 5.00
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, Ltd. (3 from 42,496 patents)
3 patents:
1. 5548174 - Steel rotor shafts of electric machines
2. 5437742 - Steel rotor shafts for electric machines
3. 5288455 - Steel for rotor shafts of electric machines and method and product