Patents by Inventor Osamu Takadama

Osamu Takadama 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).

  • Side bar type cylinder lock with variable key code
    Patent number: 6755063
    Abstract: In a side bar cylinder lock with a variable key code, plug (6) engages within casing (1) at two opposite portions in preventing plug (6) from rotating in locking state. This improves the lock in resistance to attack. Plug (6) has holes (8) each receiving a tumbler plate (11) and variable tumbler (14) side by side therein. When plug (6) is rotated to have a bulged portion (21) of said bar holder (19) abut against concave portion (2) of casing (1), spring (25) forces end portion (26) of plate (11) to enter receiving hole (9) of plug (6), and forces a bulged portion (21) of holder (19) to engage with concave portion (2) of casing (1), whereby engaging portion (13) of plate (11) is disengaged from an engaged portion (15) of variable tumbler (14). After such disengagement, variable tumbler (14) is rotated through an angle to change the key code to a new one.
    Type: Grant
    Filed: February 4, 2003
    Date of Patent: June 29, 2004
    Assignee: Takigen Manufacturing Co. Ltd.
    Inventor: Osamu Takadama
  • Side bar type cylinder lock with variable key code
    Publication number: 20040069030
    Abstract: In a cylinder lock with a variable key, plug (6) engages with casing (1) at two portions in preventing plug (6) from rotating in locking state. This improves the lock in resistance to attack. Plug (6) has holes (8) each receiving a tumbler plate (11) and variable tumbler (14) side by side therein. When plug (6) is rotated to have a bulged portion (21) of side bar holder (19) abut against concave portion (2) of casing (1), spring (25) forces end portion (26) of plate (11) to enter receiving hole (9) of plug (6), and forces a bulged portion (21) of holder (19) to engage with concave portion (2) of casing (1), whereby engaging portion (13) of plate (11) is disengaged from an engaged portion (15) of variable tumbler (14). After such disengagement, variable tumbler (14) is rotated through an angle to change the key code to a new one.
    Type: Application
    Filed: February 4, 2003
    Publication date: April 15, 2004
    Applicant: Takigen Manufacturing Co., Ltd.
    Inventor: Osamu Takadama