Patent ID: 6725736
Filing Date: 2004-04-27
Classification: B06B,E01C,Y10T

Abstract:
A rotatable eccentric arrangement adapted for stepless adjustment of vibration amplitude, comprising a rotatable shaft with at least one fixed eccentric weight arranged in a fixed manner thereon and at least one movable eccentric weight which is pivotable relative to the fixed weight between a position with minimum amplitude and a position with maximum amplitude for changing the vibration amplitude of the arrangement, the movable eccentric weight being restrained in its motion relative to the fixed eccentric weight to less than about one hundred eighty degrees of rotation and characterized in that a pivoting axis for the pivoting of the movable eccentric weight is displaced from the axis of rotation of the shaft towards the center of gravity of the fixed weight and that the movable weight is adapted so as to be automatically pivoted toward the position with maximum amplitude when a vibrational frequency decreases and towards the position with minimum amplitude when the vibrational frequency increases and in that a third weight is movably arranged and adapted such that the centrifugal force during rotation of the eccentric arrangement causes the third weight to exert a force against the movable weight so as to guide the movable weight from the position with maximum amplitude toward the position with minimum amplitude.