Average Co-Inventor Count = 3.57
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. Nhk Spring Co., Ltd. (4 from 1,233 patents)
2. Nkh Spring Co., Ltd. (1 from 4 patents)
5 patents:
1. 7458356 - Spring apparatus and valve train of internal combustion engine using the same
2. 7325571 - Pressure container and pressure accumulating/buffer apparatus
3. 6525290 - Accumulator and manufacturing process thereof
4. 6378848 - Gas spring apparatus
5. 6286552 - Accumulator and manufacturing process thereof