Company Filing History:
Years Active: 1987-1989
Title: **Innovator Tetsuji Hirotsu: Pioneering Electric Rolling Stock Technology**
Introduction
Tetsuji Hirotsu is a notable inventor based in Katsuta, Japan, with a strong reputation in the field of electric rolling stock technology. With three patents to his name, Hirotsu has made significant contributions to enhancing the performance and efficiency of railway vehicles.
Latest Patents
One of Hirotsu's latest innovations is a **control apparatus for maintaining traction in electric rolling stock**. This invention allows for the early detection of the onset of slip by analyzing the time-differential value of the creep velocity. The termination of the slip is identified when the peripheral velocity of the driving wheel reaches zero. This system simplifies the arithmetic logic operations necessary for control while maintaining high adhesion performance in electric vehicles.
Another notable patent is a **truck for railway vehicles** that features a unique arrangement allowing optimal steering operations of each wheel-and-axle when navigating curved tracks. The design simplifies the construction of the journal box locator, which fits the journal box to the truck frame in a manner that allows for upward movement relative to the truck's center axis. This innovative approach provides enhanced flexibility through elastic deformation of members, improving the overall performance of railway vehicles.
Career Highlights
Tetsuji Hirotsu works at Hitachi, Ltd., a leading technology company renowned for its contributions to the transportation sector. His work at Hitachi has positioned him as a key player in railway innovations, reflecting the company's commitment to developing advanced technologies.
Collaborations
Throughout his career, Hirotsu has had the privilege of collaborating with talented coworkers, including Kiyoshi Nakamura and Hisakatsu Kiwaki. Together, they have driven forward several innovative projects that enhance the functionality and safety of railway systems.
Conclusion
Tetsuji Hirotsu exemplifies the spirit of innovation within the railway industry. His contributions, particularly in traction control and truck design for electric rolling stock, showcase his dedication to improving transportation technologies. As the railway sector continues to evolve, Hirotsu's patents are likely to play a crucial role in shaping the future of railway systems in Japan and beyond.