This inventor holds 1 USPTO granted patent. Top assignees: Keeper Corporation, Ntn Corporation. Active years: 2026.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile
Company Filing History:
1 out of 22 
1 out of 2,501 
Years Active: 2026
Title: Kouji Masujima: Inventor of a Flexible Constant-Velocity Joint Boot
Introduction
Kouji Masujima is an inventor associated with Kanagawa, Japan. His work includes an invention designed to improve the flexibility and durability of boots used in constant-velocity universal joints. His patent record includes 1 patent.
Latest Patents
Masujima’s patent, “Flexible Boot for Constant Velocity Universal Joint and Constant Velocity Universal Joint,” describes a boot with attachment portions at both ends and a bent section between them. The bent section absorbs deformation as the joint operates.
The boot is made from a rubber blend containing 50 to 80 parts by weight of hydrogenated nitrile rubber (HNBR), with an acrylonitrile content of 15 to 21 percent, and 20 to 50 parts by weight of ethylene propylene diene monomer (EPDM). The material is specified to have an elastic recovery rate of at least 18 percent at −40°C in a TR test.
Career Highlights
Masujima is associated with NTN Corporation and Keeper Corporation. The available information connects his inventive work with automotive joint components and rubber-material engineering.
Collaborations
His listed coworkers include Mika Kohara and Sho Takeshita.
Conclusion
Kouji Masujima’s patent focuses on a flexible, cold-resistant boot intended to accommodate deformation in constant-velocity universal joints.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile