Average Co-Inventor Count = 5.71
ph-index = 4
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. (4 from 42,485 patents)
2. Hitachi Information & Control Solutions, Ltd. (4 from 18 patents)
3. Hitachi Power Semiconductor Device, Ltd. (45 patents)
4 patents:
1. 8421395 - Synchronous motor and control method of synchronous motor
2. 8035330 - Apparatus and method for driving synchronous motor
3. 7859210 - Semiconductor device for driving motor, three-phase motor and motor driving apparatus with the semiconductor device and fan motor
4. 7839113 - Apparatus and method for driving synchronous motor