Average Co-Inventor Count = 3.00
ph-index = 1
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. (2 from 42,517 patents)
2. Hitachi Metals, Ltd. (1 from 2,333 patents)
3. Hitachi Koki Co., Ltd. (1 from 1,267 patents)
2 patents:
1. 5021810 - Printing machine
2. 4763135 - Thermal-head recording device and method