Yoshihisa Kiyotoki

This inventor holds 14 USPTO granted patents and 3 published patent applications, plus 1 CIPO patent and 1 EPO patent. Top assignees: Hitachi-Ge Nuclear Energy, Ltd., Hitachi, Ltd., Okano Valve Mfg. Co. Ltd.. Active years: 1992-2025.

IDiyas Innovation Intelligence. (2026). Inventor Profile: Yoshihisa Kiyotoki. Retrieved from https://idiyas.com/inventor/yoshihisa-kiyotoki

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

USPTO Granted Patents = 14 (Patent Applications = 3)

% Patents Active = 92.9

CIPO Patents = 1

EPO Patents = 1 (Patent Applications = 3)

Average Co-Inventor Count = 3.9

ph-index = 3

Forward Citations = 55(Granted Patents)

Location History:

Tokyo, JP (2004)
Hitachinaka, JP (2005 - 2014)
Hitachi, JP (1992 - 2024)

Company Filing History:

7 out of 155

Hitachi-Ge Nuclear Energy, Ltd.

Okano Valve Mfg. Co. Ltd.

patents

where one patent can have more than one assignee

Years Active: 1992-2025

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14 patents (USPTO):Sort by Forward CitationsExplore Patents

1. 12502727 - Corrosion and wear resistant overlay, method for forming corrosion and wear resistant overlay, and corrosion and wear resistant valve (2025-12-23),

2. 11946554 - Fluid contact member and method of manufacturing fluid contact member (2024-04-02),

3. 11684976 - Method of manufacturing transition piece and transition piece (2023-06-27),

4. 10872704 - Water injection device (2020-12-22),

5. 10260651 - Butterfly valve formed of a laminated material (2019-04-16),

6. 9916908 - Gas supply apparatus and air or nitrogen supply apparatus of nuclear plant (2018-03-13),

7. 8888069 - Valves having high wear-resistance and high corrosion-resistance (2014-11-18),

8. 7584668 - Monitoring system for valve device (2009-09-08),

9. 6959916 - Valve and manufacturing method thereof (2005-11-01),

10. 6896978 - Joint construction of cobalt-based alloy (2005-05-24),

11. 6889957 - Joint construction of cobalt-based alloy (2005-05-10),

12. 6886809 - Joint construction of cobalt-based alloy (2005-05-03),

13. 6672330 - Valve bonded with corrosion and wear proof alloy and apparatuses using said valve (2004-01-06),

14. 5156197 - Float type liquid level meter (1992-10-20),

Title: Yoshihisa Kiyotoki: Innovator in Fluid Contact Technology

Introduction

Yoshihisa Kiyotoki is a prominent inventor based in Hitachinaka, Japan. He has made significant contributions to the field of fluid contact technology, holding a total of 14 patents. His work focuses on enhancing the performance and durability of fluid contact members and transition pieces.

Latest Patents

Kiyotoki's latest patents include a fluid contact member and a method of manufacturing this member. The fluid contact member is designed to improve corrosion resistance compared to existing technologies. It features a cobalt-based alloy phase with a dendrite structure and a compound phase containing chromium carbide. The average interval between adjacent secondary arms in the dendrite is optimized to be 5 μm or less, preferably 3 μm or less. Additionally, he has developed a method for manufacturing a transition piece that allows for high flexibility in adjusting length and shape. This transition piece facilitates dissimilar metal welding and incorporates an intermediate layer formed through an additive manufacturing method.

Career Highlights

Throughout his career, Kiyotoki has worked with notable companies such as Hitachi, Ltd. and Hitachi GE Nuclear Energy, Ltd. His experience in these organizations has contributed to his expertise in innovative manufacturing processes and materials.

Collaborations

Kiyotoki has collaborated with esteemed colleagues, including Mitsuo Chigasaki and Shizuo Matsushita. Their joint efforts have further advanced the development of technologies in fluid contact applications.

Conclusion

Yoshihisa Kiyotoki's contributions to fluid contact technology and his innovative patents reflect his dedication to improving industrial applications. His work continues to influence the field and showcases the importance of innovation in engineering.

Profile summary based on public USPTO records.