Patents by Inventor Takaji Watabe

Takaji Watabe 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).

  • Patent number: 4763384
    Abstract: In a door closer, there are provided a vertical rotatable shaft associated with the rotation of a door through an arm, two cams installed integral with the shaft, an urging device for rotating the door in the closing direction through one of the cams and a cylinder device for braking the door during door closing operation through the other of the cams. Thus, the opening of the door is effected by overcoming the force of the urging device and hence the door can be opened lightly. When the door is released, the force of the urging device is transmitted to the one cam and then to the arm, so that the door can be automatically closed. During door closing operation, the cam surface of the other cam pushes the piston rod of the cylinder device, whereby the rotation of the other cam and hence the rotation of the shaft connected with the other cam are braked, avoiding severe shocks to the door.
    Type: Grant
    Filed: October 7, 1986
    Date of Patent: August 16, 1988
    Assignee: Santo Industries Co., Ltd.
    Inventor: Takaji Watabe