Cone vibrating mill and process for adjusting the operation of such a mill

A process for adjusting a grinding mill comprising a support structure, a frame movable with respect to the support structure, a bottomless bowl supported on the frame, means for imparting circular and approximately horizontal vibrations to the bowl, and a cone fitted inside the bowl and mounted on the support structure for free rotation around an axis of the cone, the bowl and the cone defining a gap therebetween for receiving a layer of a material to be ground upon rotation of the cone, and for the ground material to be discharged in a discharge plane, which process comprises the steps of

• (a) measuring the speed of rotation of the cone around the axis,
• (b) determining a minimum thickness of the layer of ground material in the discharge plane on the basis of a measured value of the speed of rotation of the cone and a width of the gap in the discharge plane when the mill is at a standstill, and
• (c) adjusting the frequency and/or amplitude of the bowl vibrations so as to maintain the minimum thickness of the layer at a set value.