Patents Examined by B. Mizaki
  • Method and equipment for attenuation of oscillation in a paper machine or in a paper finishing device
    Patent number: 6911117
    Abstract: A method and apparatus for damping vibration in a paper machine. The apparatus having a dynamic damper which includes a weight suspended by a spring. The spring constant of the spring is changed by means of a control device in order to tune the natural frequency of the dynamic damper. The dynamic damper is tuned to a frequency that is substantially equal to a multiple of the rotational frequency of the roll in the paper machine that is being damped.
    Type: Grant
    Filed: April 22, 1998
    Date of Patent: June 28, 2005
    Assignee: Metso Paper, Inc.
    Inventors: Jouko Karhunen, Arto Puranen, Jorma Köliö, Esa Lehtovirta, Erkki Hietamäki