Company Filing History:
2 out of 106 
1 out of 327 
1 out of 1 Years Active: 1988-1993
Title: Nobumasa Umezawa: Innovator in High Strength Spring Steel
Introduction
Nobumasa Umezawa is a notable inventor based in Funabashi, Japan. He has made significant contributions to the field of materials science, particularly in the development of high strength spring steel. With a total of 3 patents to his name, Umezawa's work has had a considerable impact on various industrial applications.
Latest Patents
Umezawa's latest patents focus on high strength spring steel formulations. One of his patents discloses a high strength spring steel consisting of, in weight percentage, 0.50 to 0.70% C, 1.00 to 2.50% Si, 0.30 to 1.20% Mn, 0.80 to less than 1.20% Cr, 0.05 to 0.3% Mo, 0.05 to 0.30% V, 0.01 to 0.30% Nb, 0.005 to 0.100% Al, and the balance being Fe and unavoidable impurities. This steel exhibits high hardness coupled with high toughness, making it particularly useful for springs in suspension devices and various industrial machines. Another patent also focuses on high strength spring steel, consisting of 0.40 to 0.70% C, 0.50 to 2.00% Si, more than 0.50 to 1.50% Mn, 0.50 to 2.50% Ni, 0.20 to 1.50% Cr, more than 0.60 to 1.50% Mo, 0.01 to 0.50% V, 0.01 to 0.50% Nb, 0.005 to 0.100% Al, and the balance being Fe and unavoidable impurities. This formulation also demonstrates high hardness and toughness, suitable for similar applications.
Career Highlights
Throughout his career, Umezawa has worked with prominent companies such as Mitsubishi Steel Manufacturing Co., Ltd. and Nippon Petrochemicals Company, Limited. His experience in these organizations has contributed to his expertise in materials development and innovation.
Collaborations
Umezawa has collaborated with notable coworkers, including Tsuyoshi Abe and Tatsuo Fukuzumi.