Average Co-Inventor Count = 1.60
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. Yamaha Corporation (2 from 5,451 patents)
2. Nippon Gakki Seizo Kabushiki Kaisha (1 from 841 patents)
3. Nippon Gakki Kabushiki Kaisha (1 from 1 patent)
4 patents:
1. 6922379 - Disk changer apparatus
2. 6683827 - Disk storage apparatus and disk changer apparatus with enhanced access to disks
3. 4609786 - Band and the headphone utilizing the same
4. 4460991 - Pickup device for disc player