JPH0232939B2 - KEEJIGATAMIRU - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to improvements in cage-type mills for crushing hard materials such as stones and gravel.

A cage-type mill has a cage-shaped (i.e., cage-shaped) rotor by arranging a large number of pins on the circumference of a disk provided in the casing.
By rotating such a rotor, the crushed material collides with the pin or casing, and the impact force is used to crush gravel and the like. The basic structure of such a cage mill is disclosed in Japanese Patent Publication No. 48-33055.

In conventional cage mills, the wear parts are made of high chrome steel, but when applied to highly hard raw materials, the service life is short, resulting in an excessively high lining cost. In particular, the part of the cage that functions as a rotor that comes into direct contact with the raw material is subject to severe wear.

This invention was made in view of these circumstances, and by significantly increasing the lifespan,
The purpose of the present invention is to provide a cage mill that can reduce complicated replacement work and has extremely good work efficiency.

In order to achieve this object, the present invention includes a casing, a disk provided to rotate within the casing, a large number of pins attached to the disk via shafts at equal intervals and concentrically, and tips of the pins. In the cage type mill, the pin is configured as a ceramic pin, and the inner side of the disk or the inner side of the ring is covered with a plurality of ceramic linings, and the tip of the ceramic pin is covered. The gist of the present invention is a cage-type mill characterized in that a fitting portion is formed in the ceramic lining.

In the cage type mill according to the present invention, each pin is made of ceramic pins and the inside of the disc or ring is covered with a ceramic lining, so that the wear resistance is improved and the service life is significantly increased.

Furthermore, in the present invention, since the fitting part (for example, a circular hole made by matching two semicircular recesses) is formed in the ceramic lining so as to cover the tip of the ceramic pin, the cage-type mill can be used. During use, the crushed material crushed by the high-speed rotation of the cage is difficult to enter between the ceramic pin and the ring, etc., so that wear of the shaft can be avoided.

As a result, the installation of ceramic lining and
By covering the tip of the ceramic pin with the fitting portion, wear resistance and life were synergistically increased.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic perspective view showing an example of a cage mill according to the present invention. A casing 2 is provided on the base 1 via a frame 18. As shown in FIG. 2, two disks 3 and 4 are arranged concentrically inside the casing 2. The center of the disc 3 is connected to a drive shaft 5. The center of the other disc 4 is connected to another drive shaft 6. These drive shafts 5 and 6 are rotatably supported by bearings (not shown), and each is driven by a separate electric motor (not shown) so that they rotate in opposite directions. There is.

A plurality of ceramic pins 7, 8 are attached concentrically and at equal intervals on the circumference of each disk 3, 4. Rings 9 and 10 having different diameters are provided at the tips of the pins 7 and 8, respectively. A through hole is formed in the center of the ceramic pins 7, 8, through which the shafts 11, 12 pass.

One end of each shaft 11, 12 is fixed to the discs 3, 4 with nuts 13, 14. The other ends of the shafts 11, 12 protrude slightly through the holes in the rings 9, 10, and the rings 9, 10 are fixed by nuts 13, 14.

As will be explained in detail later, gaps are provided at the ends of each ceramic pin 7, 8.

The aforementioned large number of ceramic pins 7 and 8 constitute a cage-shaped rotor having different dimensions. Generally, the large-diameter disk 3 and the ceramic pin 7 fixed thereon are called a large cage, and the small-diameter disk 4 and the ceramic pin 8 fixed thereon are called a small cage.

In the example shown in the figure, the number of rows of ceramic pins is two, but there are also other types such as one-row format (in that case, one disc), four-row format, six-row format, etc. There is. As the size to be crushed or crushed becomes finer, the number of rows of ceramic pins generally increases. The particle size can also be changed by changing the rotation speed of the disk.

The outside of the large cage is surrounded by a housing 2. Although the housing 2 has a nearly cylindrical shape in the illustrated example, it may have any other shape.

In use, the raw material is supplied from the hopper 15 to the center of the small cage, that is, the drive shaft 6, and is first hit by the pin 8 of the small cage, thrown toward the outer periphery, and then rotated in the opposite direction. Large cage ceramic pin 7
It is hit by a hammer and shattered into even smaller pieces. Finally, the raw material is released from the ceramic pin 7 of the large cage to the outer periphery and is finally crushed by the breaker plate 17 provided on the inner peripheral surface of the housing 2.
Thereafter, the crushed material is discharged by its own weight from the outlet 16 in the lower part of the housing 2.

The inner centers of the rings 9 and 10 are covered with U-shaped ceramic linings 30 and 31, respectively. It is also preferable that the discs 3 and 4 are covered with ceramic linings 32 and 33, respectively. Furthermore, inside the housing 2,
Covers 34 and 35 are provided. The breaker plate 17 is also preferably made of ceramic.

As described above, in the embodiment shown in FIG. 2, it is preferable that all the parts where the raw materials collide are lined with ceramic material.

Particularly in cage mills, when the ring is worn and the wall thickness decreases, the gap between the ring and the ceramic pin expands, and fine crushed materials pass through the gap and wear the shaft, which reduces the durability of the cage mill. This will have a significant impact on sexuality.

Although the present invention is applicable to both large cages and small cages, the explanation will be given below using the large cage as an example.

Lining can be done with adhesive alone, or as shown in FIG. 3, a sector-shaped lining 30 can be stretched between each ceramic pin 7 with adhesive, and then a bolt or the like can be passed through the hole 30a of the lining 30 to fix it to the ring 9. There is a way. A lining 30 is stretched around the entire circumference of the ring 9. A fan-shaped lining 32 is also connected to and stretched over the disc 3, and is fixed with a suitable fixture or adhesive.

In the embodiment of FIG. 4, the ceramic pin 7
A gap is formed between the shaft 11 and the through hole 7a formed at the center of the shaft 11, and the adhesive 20 is filled in the gap. This maintains the ceramic pin 7 and shaft 11 in a fixed relationship. There are male screws 11a on both ends of the shaft 11.
is formed. Furthermore, small cylindrical notches are formed at both ends of the ceramic pin 7, and spacers 21 are placed in the notches. An adhesive 20 is also filled between the spacer 21 and the notch of the ceramic pin 7. Due to the presence of the spacer 21, a gap S of about 1 to 3 mm is provided between the linings 30, 32 and the ceramic pin 7, respectively.

The ring 9 is fixed between the nut 13 and the spacer 21 by screwing the nut 13 into the male thread 11a of the shaft 11.

A spacer 21 for the disk 3 is also fixed to the disk 3 in the same manner as the ring 9.

As the adhesive 20, epoxy resin or other binder can be used.

The embodiment of FIG. 5 is very similar to the embodiment of FIG. 4, except that there is no adhesive 20 between the spacer 21 and the ceramic pin 7. That is, the ceramic pin 7 and the spacer 21 are in direct contact with each other, and the spacer 21 can be removed from the shaft 11 if necessary. In this example, the thickness of the spacer 21 can be easily adjusted.

When the cage mill according to the present invention was used, it was found that the practical effects were remarkable as shown below.

In a cage mill of the four-row (ie two small cages and two large cages) type, the ceramic pins 7, 8 are made of alumina porcelain with 96% Al ₂ O ₃ . Rocks measuring 5 to 15 mm were used as raw material and crushed into sand. The circumferential speed was 31 m~sec, and the rotational speed was 525 r.pm.

After the start of use, we confirmed that it became possible to process more than 20,000 tons of raw materials.

In contrast, in a comparative experiment using a conventional cage mill with pins made of high-chromium steel, the shaft became visible after processing 3,850 tons of raw material, and the pins had to be replaced with new ones.

As a result, it was revealed that the cage mill according to the present invention had about five times the durability compared to the conventional cage mill. In particular, the durability was particularly improved when the second pin from the outside was made of silicon nitride and the other rows of pins were made of alumina porcelain.

[Brief explanation of drawings]

Fig. 1 is a schematic perspective view showing an example of a cage mill according to the present invention, Fig. 2 is a schematic vertical cross-sectional view showing the inside of the cage mill shown in Fig. 1, and Fig. 3 is a line XX in Fig. 2.
FIG. 4 is an enlarged cross-sectional view of the lining shown in FIG. 2 and its related parts, and FIG. 5 is a cross-sectional view corresponding to FIG. 4, showing a modification of the present invention. It is a diagram. 1...Base, 2...Casing, 3, 4...
Disc, 5, 6... Drive shaft, 7, 8... Ceramic pin, 9, 10... Ring, 11, 12... Shaft, 13, 14... Nut, 30-33... Lining, 34, 35... ...Cover, S...Gap.

Claims (1)

[Claims] 1. A cage-type mill comprising a casing, a disk provided to rotate within the casing, a number of pins attached to the disk via shafts at equal intervals and concentrically, and a ring provided at the tip of the pin. In this method, the pin is configured as a ceramic pin, and the inside of the disk or the inside of the ring is covered with a large number of ceramic linings, and a fitting part is formed on the ceramic lining so as to cover the tip of the ceramic pin. A cage type mill characterized by its structure.