Patents by Inventor Taro Matsunaga

Taro Matsunaga has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Mainspring mechanism and device having the same
    Patent number: 6763915
    Abstract: A winding stem (10) is connected to an inner end (11a) of a mainspring (11), and an outer end (11b) of the mainspring (11) is connected to a barrel drum (12). A braking plate (15) is placed inside a braking case (14), and the braking case (14) is filled with a fluid (16). An uneven joint portion (10b) is formed at the lower end of the winding stem (10), and is engaged with an uneven joint portion (15b) of the braking plate (15) placed in the braking case (14). By adopting the above configuration which can simplify the structure of the mainspring mechanism having the braking plate and which can reduce the number of components, the size and production cost of the mainspring mechanism can be reduced.
    Type: Grant
    Filed: October 15, 2001
    Date of Patent: July 20, 2004
    Assignee: Seiko Epson Corporation
    Inventors: Shoichi Nagao, Eiji Morikuni, Taro Matsunaga
  • Mainspring mechanism and device having the same
    Publication number: 20030066713
    Abstract: A winding stem (10) is connected to an inner end (11a) of a mainspring (11), and an outer end (11b) of the mainspring (11) is connected to a barrel drum (12). A braking plate (15) is placed inside a braking case (14), and the braking case (14) is filled with a fluid (16). An uneven joint portion (10b) is formed at the lower end of the winding stem (10), and is engaged with an uneven joint portion (15b) of the braking plate (15) placed in the braking case (14). By adopting the above configuration which can simplify the structure of the mainspring mechanism having the braking plate and which can reduce the number of components, the size and production cost of the mainspring mechanism can be reduced.
    Type: Application
    Filed: October 15, 2001
    Publication date: April 10, 2003
    Inventors: Shoichi Nagao, Eiji Morikuni, Taro Matsunaga