Patent ID: 7789731

Claim:
An oscillating grinding machine comprising a driving motor surrounded by a body, and a two part unitary rigid drive shaft that directly cooperates with the driving motor and comprises a grinding head as a support for a flexible grinding product, the grinding head being mounted in bearings for free rotation around the drive shaft, wherein the drive shaft extends to the driving motor and comprises a main shaft part and an eccentric shaft part connected rigidly thereto and extending from one end of said main shaft in such a manner that the eccentric shaft having a center line that assumes an angle relative to a corresponding center line comprised by the main shaft and that the grinding head is coupled to the eccentric shaft for an eccentric placement in relation to the main shaft, the grinding head being arranged to assume an oscillation in a substantially spherical plane created by the rotation of the main shaft and the eccentricity and inclination of the eccentric shaft in relation to the main shaft whereby rotational symmetric grinding can be achieved.