METHOD AND EQUIPMENT FOR ATTENUATION OF OSCILLATION IN A PAPER MACHINE OR IN A PAPER FINISHING DEVICE

摘要

The invention relates to a method for damping vibration in a paper machine or in a paper finishing device by means of a dynamic damper which comprises an additional weight suspended from a vibrating object by means of a spring. In the method, the spring constant of the spring (3) of the dynamic damper and/or the mass (4) of the dynamic damper is/are changed by means of a control device (9) in order to tune the natural frequency of the dynamic damper. In an advantageous application of the invention, the vibration induced by rolls (1) which are in nip contact is damped by means of the damper so that the damper is tuned to a frequency that is substantially equal to a multiple of the rotational frequency of the roll that is closest to the natural frequency of the vibrating system. The invention also relates to an apparatus.