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For the Inventor, By the Inventor

Nagano, Japan

Chang Junhua

This inventor holds 10 USPTO granted patents. Top assignee: Seiko Epson Corporation. Active years: 2004-2007.

IDiyas Innovation Intelligence. (2026). Inventor Profile: Chang Junhua. Retrieved from https://idiyas.com/inventor/chang-junhua

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

Calculating rank
USPTO Granted Patents = 10

% Patents Active = 30.0

Average Co-Inventor Count = 1.2

ph-index = 5

Forward Citations = 84(Granted Patents)


Company Filing History:

goldMedal10 out of 34,333 
 
Seiko Epson Corporation
 patents

Years Active: 2004-2007

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10 patents (USPTO):Explore Patents
1. 7210770 - Actuator device, liquid ejection head, and method of inspecting the same (2007-05-01),
2. 7207664 - Actuator device, liquid ejection head, and method of inspecting the same (2007-04-24),
3. 7152290 - Methods of manufacturing a piezoelectric actuator and a liquid jetting head (2006-12-26),
4. 7114797 - Actuator device, liquid ejection head, and method of inspecting the same (2006-10-03),
5. 6997547 - Piezoelectric element, piezoelectric actuator and liquid jetting head incorporating the same (2006-02-14),
6. 6949869 - Piezoelectric actuator, liquid jetting head incorporating the same, piezoelectric element, and method of manufacturing the same (2005-09-27),
7. 6918659 - Piezoelectric element, piezoelectric actuator and liquid ejection head incorporating the same (2005-07-19),
8. 6803703 - Piezoelectric actuator, liquid jetting head incorporating the same, and method of manufacturing the actuator and head (2004-10-12),
9. 6779866 - Liquid jetting apparatus and method for driving the same (2004-08-24),
10. 6685293 - Liquid jetting apparatus and method of driving the same (2004-02-03),

Title: Chang Junhua: Innovator in Piezoelectric Technology

Introduction

Chang Junhua is a prominent inventor based in Nagano, Japan. He has made significant contributions to the field of piezoelectric technology, holding a total of 10 patents. His work focuses on actuator devices and liquid ejection systems, which are essential in various applications.

Latest Patents

Among his latest patents, Chang has developed an actuator device and a liquid ejection head, along with methods for inspecting these technologies. His innovative designs include a vibration plate that is joined to a substrate, forming part of a pressure-generating chamber. The first piezoelectric element is strategically placed on the vibration plate, which faces the pressure chamber. This element consists of multiple layers, including electrodes and piezoelectric layers, designed to measure electrostatic capacity effectively. The arrangement of the second piezoelectric element adjacent to the first enhances the functionality of the device.

Career Highlights

Chang Junhua is currently employed at Seiko Epson Corporation, where he continues to push the boundaries of technology. His expertise in piezoelectric devices has positioned him as a key player in the industry, contributing to advancements that improve efficiency and performance in various applications.

Collaborations

Chang has collaborated with notable coworkers, including Takahiro Katakura and Motonori Okumura. Their combined efforts have led to innovative solutions and advancements in their respective fields.

Conclusion

Chang Junhua's contributions to piezoelectric technology and actuator devices have made a significant impact in the industry. His innovative patents and collaborations reflect his dedication to advancing technology and improving efficiency in various applications.

Profile summary based on public USPTO records.
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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