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Nippon Piston Ring Co., Ltd.

USPTO Granted Patents = 230

% Expired Patents = 6.5

EPO Patents = 27

Trademarks = 5

Forward Citations = 1,795

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221 inventors (with patents filed for the assignee):

Hiroshi Sakamaki (28 out of 37 patents)

Yukio Horikoshi (20 out of 22 patents)

Shunsuke Takeguchi (18 out of 18 patents)

4. Shigeru Urano (17 out of 18 patents)

5. Katsuaki Ogawa (16 out of 18 patents)

6. Yoshikatsu Nakamura (16 out of 16 patents)

7. Teruo Takahashi (14 out of 21 patents)

8. Takeshi Hiraoka (14 out of 14 patents)

9. Osamu Kawamura (13 out of 13 patents)

10. Susumu Sugishita (13 out of 14 patents)

11. Hiroyuki Sugiura (11 out of 41 patents)

12. Kentaro Takahashi (11 out of 11 patents)

13. Hiroshi Oshige (10 out of 10 patents)

14. Genkichi Umeha (10 out of 10 patents)

15. Motonobu Onoda (9 out of 9 patents)

Core Competencies:

Piston Ring

Sliding Member

Oil Ring

Valve Seat

Sintered Alloy

Coating Film

Internal Combustion Engine

Manufacturing Method

Wear Resistance

Titanium Alloy

Fusible Plug

Hard Carbon Coating

230 patents: Sort by Forward Citations

1. 12516731 - Sliding member, manufacturing method thereof, and coating film (2026-01-06),

2. 11946010 - Sliding member, manufacturing method thereof, and coating film (2024-04-02),

3. 11873780 - Combined oil ring (2024-01-16),

4. 11859766 - Fusible plug (2024-01-02),

5. 11846009 - Hard particle powder for sintered body (2023-12-19),

6. 11739840 - Piston ring (2023-08-29),

7. 11692248 - Sliding member (2023-07-04),

8. 11549408 - Iron-based sintered alloy valve seat for internal combustion engine (2023-01-10),

9. 11293548 - Sliding member and coating film (2022-04-05),

10. 11261519 - Coating film, manufacturing method therefor, and PVD apparatus (2022-03-01),

11. 11111875 - Sliding structure for internal combustion engine, method for controlling idling operation, and method for controlling operation of internal combustion engine (2021-09-07),

12. 11051904 - Marker for use in living body and instrument set for inserting marker for use in living body (2021-07-06),

13. 11047479 - Method for producing piston ring with recess (2021-06-29),

14. 10724636 - Combined oil ring (2020-07-28),

15. 10669613 - Titanium alloy (2020-06-02),

Company Overview

Nippon Piston Ring Co., Ltd., headquartered in Saitama, Japan, specializes in the development and manufacturing of piston ring technology and related components. The company focuses on innovative solutions for internal combustion engines, including sliding members, oil rings, and valve seats. With expertise in sintered alloys and advanced coating films, Nippon Piston Ring is committed to enhancing engine performance and efficiency through cutting-edge manufacturing methods and materials, serving a global automotive market.

Profile summary synthesized from public USPTO records and patent filings.

Company Badge

USPTO Data Jan 1 1976 - Oct 13 2026

230 Patents

#14 in

#641 in

#3,732 in the World

Nippon Piston Ring Co., Ltd.

Forward Citations = 1,795

221 inventors:

Hiroshi Sakamaki (28 out of 37 patents)

Yukio Horikoshi (20 out of 22 patents)

Shunsuke Takeguchi (18 out of 18 patents)

4. Shigeru Urano (17 out of 18 patents)

5. Katsuaki Ogawa (16 out of 18 patents)

IDiyas Innovation Intelligence. (2026). Company Patent Portfolio: Nippon Piston Ring Co., Ltd.. Retrieved from https://idiyas.com/company/nippon-piston-ring-company

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

Data Sources: USPTO Patent Grant XML, Patent Center, EPO & CIPO • Normalized by IDiyas Innovation Graph. Methodology & provenance architecturePlease report any incorrect information to [email protected]

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