RU2252077C1 - Roller centrifugal mill - Google Patents

Abstract

FIELD: disintegrating by milling.

SUBSTANCE: roller centrifugal mill comprises cylindrical housing with branch pipes for supplying and discharging a material to be processed. The housing receives coaxially mounted driving shaft with a separator that holds milling members. The separator is made of plates secured to the driving shaft along a spiral to allow it to play a role of the spiral fan. The edges of the plates that face the cylindrical housing are provided with openings for locking milling members. In the region of the outlet branch pipe the mill is additionally provided with a relief disk.

EFFECT: enhanced efficiency of milling.

2 dwg

Description

The invention relates to devices for grinding and can be used in the production of powder materials to obtain a product with a given dispersion.

A device is known (Patent RU No. 2104092, publ. 10.02.1998) containing a container, a shaft located along the axis of the container, lower and upper pressure plates connected to the shaft, made with shoulder-like protrusions, rigidly connected to the axis plates, on which ring-shaped elements are mounted , and a mixing vane mounted on the shaft.

The disadvantages of this device are the large contact surface between the grinding elements (discs) proper, significantly larger than the contact surface between the grinding bodies and the material to be ground, which causes their intensive abrasion and contamination of the product with the material of the grinding bodies, the presence of non-overlapped sections of the central space of the mill between the shafts, on which the disks are located, leading to the possibility of a “slip” of particles from the inlet to the outlet with an uncontrolled degree of processing, leading to a decrease the desired degree of grinding, as well as the introduction of an additional mixing device in the design.

The closest solution selected for the prototype is a centrifugal mill (Patent RU No. 2110327, publ. 05/10/98), containing a vertical cylindrical body with loading and unloading nozzles, a rotor with a separator coaxially mounted in the housing, in which the grinding media are placed in blind radial channels in the form of a package of flat interconnected flat identical disks. The grinding process in this mill is carried out due to the movement of the grinding media along the inner cylindrical surface of the housing and the destruction of the original product in the contact zone of the grinding media with the housing.

The disadvantage of this device is the fixed working out of the inner cylindrical surface of the body due to the symmetrical location of the grinding bodies, which leads to a change in its geometry and, as a consequence, to a change in the initial grinding parameters.

The technical problem to which the invention is directed is to increase the grinding efficiency by increasing the contact surface of grinding media over the entire inner cylindrical surface of the housing and reducing wear of grinding media.

The problem is solved due to the fact that in the inventive roller centrifugal mill containing a vertical cylindrical body with nozzles for input and output of the processed material, in which the drive shaft with the separator holding the grinding media is coaxially mounted, the separator is made in the form of plates fixed to the drive shaft by spirals with the possibility of playing the role of a spiral fan, holes for fixing grinding media are made on the edges of the plates facing the cylindrical body, and in the area of the outlet the nozzle of the mill is additionally placed discharge disk.

In relation to the prototype of the claimed technical solution has the following significant distinguishing features:

- the separator is made in the form of plates mounted on a drive shaft;

- separator plates are mounted on the drive shaft in a spiral with the possibility of playing the role of a spiral fan;

- on the edges of the plates facing the cylindrical body, holes are made for fixing the grinding bodies;

- in the area of the outlet pipe of the mill an additional discharge disk is placed.

The analysis of the prior art, including a search by patent and scientific and technical sources of information, allowed us to establish that technical solutions characterized by features identical to all the essential features of the claimed were not found, which allows us to conclude that the proposed solution meets the criterion of “novelty” according to the current legislation .

The set of essential distinguishing features, as well as the fact that the separator is made of plates mounted on a drive shaft in a spiral, which allows it to simultaneously perform two functions: to hold grinding media, on the one hand, and to act as a spiral fan, on the other hand, allows us to solve set task and conclude that the claimed technical solution meets the criterion of "inventive step".

Figure 1 schematically shows a roller centrifugal mill. Figure 2 shows a cross section of the inventive mill.

A centrifugal roller mill includes a housing 1 with a cover 2, nozzles for input 3 and output 4 of the material to be processed, inside of which there is a separator consisting of plates 5, mounted on a drive shaft 6 in a spiral. The separator plates hold the grinding rollers 7, and in the area of the outlet pipe 4 on the shaft 6 of the mill there is a discharge disk 8.

Rotor rotation is carried out by an adjustable speed drive (not shown in the drawings).

The device operates as follows.

The processed material enters through the pipe 3 in the housing 1 of the apparatus. During rotation of the separator, consisting of plates 5, mounted on a drive shaft in a spiral and holding the grinding rollers 7, the latter, under the action of centrifugal forces, are pressed against the inner cylindrical surface of the housing 1, where the feed material is discarded, where it is ground. Spiral mounted separator plates hold each subsequent roller with some offset relative to the previous one and, thus, the contact surface of each roller and the inner surface of the housing (working surface) is overlapped by similar surfaces of adjacent rollers. Since the rollers are installed individually, there are no contacts between them, their wear occurs mainly only on the working surface, which leads to an increase in their service life and a decrease in rubbing in the product. At the same time, the spiral separator plates cause a ventilation effect inside the mill, improving the transportation of the processed material through the outlet 4. To increase the efficiency of unloading of the crushed material and prevent its accumulation in the lower part of the mill, in the area of the outlet 4, the mill is additionally equipped with an unloading disk 8, fixed on the drive shaft.

By changing the number of revolutions of the drive shaft, the number and mass of the rollers, the degree of grinding can be significantly changed.

Comparative analysis with the prototype shows that the inventive roller centrifugal mill, in which the separator is made of plates mounted spirally on the drive shaft, performing two functions at the same time: the role of the holder for the rollers and the fan, improves the grinding efficiency by increasing the contact surface of grinding media by the entire inner cylindrical surface of the housing and reduce wear of grinding media.

Claims (1)

A centrifugal roller mill containing a cylindrical body with nozzles for input and output of the processed material, in which the drive shaft is coaxially mounted with a separator holding grinding media, characterized in that the separator is made in the form of plates mounted on a drive shaft in a spiral with the possibility of acting as a spiral fan and having holes on the edges facing the cylindrical body for fixing the grinding bodies, and in the area of the outlet pipe the mill is additionally equipped with a discharge disk m.

Images