JPH019630Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a means for obtaining product particles of a desired particle size from a coarse material to be processed, such as mined ore, using a so-called dry tower-type grinder. The purpose is to provide a sorting and discharging means that selectively directly discharges products of different particle sizes and that can easily handle changes in particle size.

Conventionally, in dry tower-type grinding mills, ores and other materials to be processed are charged into a cylindrical processing cylinder together with grinding media such as steel balls, and the materials are agitated by a rotating screw installed vertically inside. Particles produced by a grinding action based on friction between the objects to be processed due to stirring and between the objects to be processed and the grinding medium are naturally discharged from an outlet provided in the lower part of the processing cylinder wall. in many cases. In this case, if the particle size of the product to be obtained is specified, a lattice with a lattice gap corresponding to the maximum value of the specified particle size range is provided at the outlet, and the crushed material is discharged through this lattice. After that, fine powder smaller than the minimum value of the specified particle size range is removed by sieving, air selection, etc., and the remaining crushed material is obtained. That is, since it is not possible to directly obtain a product in the desired particle size range from a pulverizer using conventional means, the product has to be obtained through a further sorting process. In particular, if the particle size within the specified range is large, because a grid with large lattice gaps is used, the waste will contain everything from the particle size corresponding to the large gap to fine powder, so the product Earning efficiency was poor.

This invention was successful in eliminating the above-mentioned drawbacks of the conventional means when trying to obtain a product with a desired particle size using a tower-type attrition mill. To explain, 1 is a cylindrical processing cylinder, and a rotary screw 2 is installed vertically inside thereof. The rotating screw 2 can be supported by any means, but in the illustrated example, the shaft 21
In the upper part than shown in the figure, it is suspended and supported by a thrust bearing (not shown) to prevent wear of the support part. However, such support means for the rotary screw 2 are known. Next, according to this invention, the opening of the outlet 3 is vertically long, and the lattice 31
is provided. The width of this opening is designed to be appropriate for maintaining the mechanical strength of the processing cylinder 1 and for collecting the waste. Regarding the length, if the specified particle size of the product is expected to be quite coarse, it should be up to a height corresponding to the considerably upper part of the blade 22 of the rotating screw 2 as shown in the figure, but it is expected that If the particle size is relatively small, the length may be shorter than shown. The lattice spacing is naturally designed to correspond to the maximum particle size of the product expected to be obtained. Further, according to this invention, a nozzle 4 whose acquisition position can be changed is attached with a screw 33 or the like so as to cover a part of the length of the opening. Also, 4
Reference numerals 1 and 42 designate cover plates in this invention, which are removably attached to cover the rest of the opening with screws 33 or the like.

This idea is made as described above, so the processing tube 1
When a coarse material to be treated such as ore is charged into the tube and the operation is started, the material to be treated repeats the movement of being pumped up by the rotary screw 2 and descending along the cylinder wall 11, during which time the material to be treated is The objects to be processed are crushed due to collisions and friction between the objects to be processed and between the objects to be processed and the above-mentioned grinding media, but according to the research of this researcher, after some time has passed from the start of operation, the objects to be processed are crushed. The particle size distribution of the product particles produced by pulverization in the processing cylinder 1 is such that the particle size is minimum at the bottom of the processing cylinder 1 and maximum at the top, and the particle size changes continuously in the middle. By the way, according to this invention, the opening provided with the lattice 31 of the outlet 3 for the particles produced by pulverization in the processing cylinder 1 is vertically long, and the nozzle 4 covers a part of the length of the opening and is removable. The remainder of the opening is covered by cover plates 41 and 42. Therefore, if the position of the nozzle 4 is selected at the height of the entire length of the opening of the outlet 3, the particles produced in the processing cylinder 1 at the level of the installation position of the nozzle 4, that is, the above-mentioned processing In view of the particle size distribution in the cylinder 1, produced particles in the particle size range specified by the mounting position of the nozzle 4 are sorted and discharged from the nozzle 4, so they are sorted again to obtain particles with a desired particle size range. No need to go through the process. The desired particle size can also be easily changed by simply changing the mounting positions of the nozzle 4 and the cover plates 41, 42.

Thus, according to this invention, a product sorted into a specified particle size range according to the requirements can be obtained directly from the crusher itself, thereby improving the efficiency of supplying mineral raw materials to the chemical industry and supplying soil and stone to the civil engineering industry. There is a lot to contribute.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional elevational view of the main part of an embodiment of a dry tower type grinding mill equipped with the device according to this invention, Fig. 2 is a partial view of the processing cylinder with the outlet viewed from the front, and Fig. 3
The figure is an enlarged plan view of the outlet. 1 is a processing cylinder, 11 is a cylinder wall, 2 is a rotating screw, 21 is a machine shaft, 22 is a blade, 3 is an outlet, 31
3 is a grid, 32 is a frame edge, 33 is a screw, 34 is a screw hole, 4 is a nozzle, 41 and 42 are cover plates, 51 is a hopper, and 52 is a rotary feeder.

Claims (1)

[Scope of utility model registration request] In a dry tower type grinding mill in which a rotary screw 2 is installed vertically inside a cylindrical processing cylinder 1, an outlet 3 with a grid 31 is provided in a part of the cylinder wall 11 of the processing cylinder 1, and In a device configured to discharge particles produced by grinding the processed material input therein from the outlet, the outlet 3 has a nozzle 4 whose mounting position can be changed, covering a part of the length of the opening. A product sorting and discharging device for a tower-type grinding mill, in which lid plates 41 and 42 which are attached and detachable are attached to cover the remainder of the length of the opening.