Method and system for controlling a layer thickness in a grinding operation

A method for grinding and homogenizing material in the form of a dispersion of particles and pasty viscous material, including chocolate, comprising the steps of

• treating said material at least in a first and in a second roller set, wherein said first roller set has at least two cooperating end rolls with an exit gap in between said end rolls, and said second roller set is a distributing roller set with at least three distributing rollers and at least one feed-in roller for feeding said material into said second roller set,
• adjusting said exit gap, and
• controlling said layer thickness by adjusting said distribution roller set wherein said controlling is made by a proportional, integral differential control system, and
• said controlling of said layer thickness includes adjusting the speed of at least one of said at least one feed-in rollers.

A system for grinding and homogenizing material in the form of a dispersion of particles and pasty viscous material, including chocolate, comprising

• at least a first and a second roller set wherein, said first roller set has at least two cooperating end rolls with an exit gap in between said end rolls, and
• said second roller set is a distributing roller set with at least three distributing rollers and at least one feed in roller for feeding said material into said second roller set,
• motor means for driving at least one distribution roller with an adjustable speed,
• at least one thickness sensor for measuring an actual layer thickness of said material at said distribution roller set,
• comparator means connected to said at least one thickness sensor for receiving at least one first signal representing said actual layer thickness, with said comparator means receiving a second signal representing a predetermined layer thickness and comparing at least said first with said second signal and creating an comparator output signal,
• control means connected to said comparator means and to said motor means for controlling said adjustable speed of at least one distribution roller,
• a threshold switching means connect to said comparator means and to said control means for activating and deactivating said controlling of said adjustable speed according to the actual level of said comparator output signal.

A system for grinding and homogenizing material in the form of a dispersion of particles and pasty viscous material, including chocolate, comprising

• at least a first and a second roller set wherein said first roller set has
• at least two cooperating end rolls with an exit gap inbetween said end rolls and
• said second roller set is a distributing roller set with at least three distributing rollers and at least one feed in roller for feeding said material into said second roller set,
• gap adjusting means connected to said first roller set for adjusting said exit gap,
• at least one thickness sensor for measuring an actual layer thickness of said material at said distribution roller set,
• comparator means connected to said at least one thickness sensor for receiving at least one first signal representing said actual layer thickness, said comparator means is receiving a second signal representing a given layer thickness and compares at least said first with said second signal and creates an comparator output signal,
• control means connected to said comparator means and to said gap-adjusting means for controlling said adjusting of said gap,
• a threshold switching means connected to said comparator means and to said control means for activating and deactivating said adjusting of said gap according to the actual level of said comparator output signal.