Patent ID: 7168640

Claim:
A comminuting apparatus for waste comprising a drive unit including at least one electric motor having a drive shaft, the electric motor comprising a three-phase synchronous motor, a comminuting shaft having at the periphery thereof comminuting tool means over a working width thereof, a counterpart means co-operable with the comminuting tool means and adapted in respect of shape to the rotational surface of the comminuting shaft for comminution of the waste material to be processed, means connecting the drive shaft of the electric motor without a transmission directly to the comminuting shaft, a frequency converter having an output, means electrically connecting the electric motor to the output of the frequency converter, and a control device connected to the frequency converter for controlling same, the arrangement being such that no drive element operable to transmit at least one of torque and force is rotatable in operation faster than the drive shaft of the electric motor.