MIXING MACHINE ROTOR WITH BUCKETS

Abstract: A mixing machine rotor provided with buckets, has the radially inner edge of each bucket preferably arranged abutting the outer surface of the rotor shaft along the entire edge length especially for fine grain masses. An interspace between the inner radially edge of the bucket and the outside of the shaft may be accepted as long as the interspace is smaller than the smallest grain size of the masses to be mixed.

Description: Mixing machine rotor with buckets The present invention is related to a mixing machine comprising a rotor having buckets, which machine is constructed as a continuously working machine or working according to the batch principle. Mixing machines of the above mentioned types are used in a variety of connections, such as for mixing of finer and less finer amounts of materials in the pharmaceutical industry and the nutrient industry as well a number of different branches of industry, also comprising mixing of bark and chips etc. The principle for such mixing machines is that the buckets set the masses into movement to such a degree that they are thrown up in a curve or casting track in such a way that the masses are mixed in this casting track with masses being casted upwardly in an oppositely directed casting track from buckets on a rotor being arranged parallel to the first-rotor and rotating in opposite direction. To achieve maximum mixing effect it is essential that as much as possible of the masses is brought up into an optimal casting track. To achieve such a casting track, a casting velocity is necessary which cannot be reached for masses being casted up from the bucket from a point relatively close to the rotor. To avoid such effect special bucket designs have been proposed where the masses are cast radially outwardly along the bucket before they are cast upwardly into the casting track by the bucket. It cannot, however, be avoided that the part of the masses will not reach the minimum velocity which is necessary to reach a casting track close to the optimal track. It is here referred to masses situated near to the rotor shaft, which masses by known mixing machine designs fall in between the buckets and the shaft. These masses naturally also will influence and partly obstruct the movement of the masses which initially has achieved suf icient velocity to reach an optimal or substantially optimal casting track. With the mixing rotor according to the present inven¬ tion, the above described disadvantages to be found in known mixing machines are avoided. The mixing machine according to the present invention being defined by the features stated in the claims. The rotor for mixing machines according to the present invention is designed in such a way that all buckets are arranged having substantially the total length of the radially inner edge of the bucket abutting the outer surface of the rotor shaft, e.g. there is preferably no clearing between the bucket and the shaft, especially for fine grain masses. Hereby is achieved that even masses situated near the rotor shaft very actively will be thrown up in a casting track by the buckets. These masses therefore will not, as the case is by prior art designs, upstruckt or in any way influence the casting tracks of the rest of the masses, but will be brought into circulation together with those masses. The distance between the inner edges of the buckets and the outside of the shaft principally is kept on a minimum. A space can, however, be accepted between the edge and the shaft surface without interfering the mixing operation as long as the space is smaller than the smallest grain size of the masses to be mixed.

Claims: Patent Claims 1. A mixing machine rotor provided with buckets, CHARACTERIZED IN the radially inner edge of each bucket prefer¬ ably abutting the outer surface of the rotor shaft along the entire edge length, a possible distance between the edge and the shaft surface always being smaller than the smallest grain size to be mixed. 2. A mixing machine rotor according to previous claim, CHARACTERIZED IN in each bucket being secured to the rotor shaft by bonding the radially inner edge of the buckets to the surface of the rotor shaft, such as by welding.

Inventors: NORDAHL GEIR, NORDAHL, GEIR
Applicants: NORDAHL GEIR, NORDAHL, GEIR
Application year: 1996
Main classification: B01F3
IPC codes: B01F3, B01F7