Modes of Vibration
Since the revolving weights create centrifugal forces in periodically changing directions, they evoke circular, linear or elliptic vibration. An external vibrator alone generates circular vibration, whereas two equal, parallel arranged and counter rotating vibrators create linear vibration.
- Circular Vibration
The vibrator moves the same mass radial to all directions; consequently the vibration width s is the same toward all directions, a circular vibration is created.
Fig. 5: Formation of circular vibration. Point p, as a part of the vibrating equipment, by constant changing centrifugal force direction, is put to circular vibration.
Fig. 6: Formation of linear vibration. Point P, through the aligning forces, is brought to linear vibration.
Fig. 7: Elliptic vibration. At the same the centrifugal forces Fc emerge different vibration widths s¬1 and s2, depending on the moving mass.
- Linear Vibration
Two equal, counter rotating external vibrators are attached parallel to each other. Due to synchronisation, the opposite forces cancel out each other and aligned forces add up. This creates linear vibration.
At conveying e.g. two counter rotating vibrators create linear motion and thus allow the motion of bulk goods toward a specific direction.
The individual particles or pieces of material are repeatedly struck at a certain trajectory so that a chain of parabola-like micro-projectile motions takes place. - Elliptic Vibration
A vibrator is mounted asymmetrically anywhere at a form, for instance at the end of a T beam. Because the vibrator has to move different masses at different directions, the vibration amplitude gets small at large mass and gets big at small mass. This changing vibration width creates elliptic vibration.