A special powder mixer
Helical spiral mixers with a cylindrical mixing chamber have been around for about 30 years. This type of mixer is equipped with a centrally-mounted mixing shaft to which radial blade-like arms are mounted. These bear a helical spring that is adapted to the diameter of the mixing chamber. The mixture is screwed upwards at the perimeter and flows downwards in the centre of the mixing chamber.
The market at that time demanded large mixers with lot sizes up to 12 m³, extremely short mixing times and a particularly gentle treatment of the mixture, especially in order to retain agglomerate structures that result, for example, from spray drying, without damage. In particular, it had to be possible to mix baby food with first-class solubility, good sinking behaviour and ideal dispersibility, ready to pack.
Extremely high mixture requirements demanded a precision mixer. This was created by fusing two vertical single-shaft mixers to form a twin-shaft mixer.
Precision mixer with complete discharge!
Increasing market penetration prompted further customer demands and accelerated the development of a conical mixer. This ensures ideal mixtures for extremely different levels of filling. Hence, for example, one and the same conical mixer can homogenise 10,000 litre batches just as well as 500 litre batches.
The upgrading of a conical mixer to a precision mixer was first made possible after a completely new type of helical spring mixing tool was invented. The helix of the mixing device and the wall of the cone form an approximate right angle. This configuration allows the zero-clearance flow of all mixtures at the same time. Hence, concave and convex helical spring forms alternate according to the task.
