JPH059138B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a crushing method and apparatus, and particularly to a crushing method and apparatus for crushing a raw material stone made of rocks, ores, etc. to a desired particle size for making sand, or corner cutting)
This invention relates to an impact crushing method and apparatus useful for crushing.

BACKGROUND OF THE INVENTION Conventionally, this type of impact crushing device is known as shown in FIGS. 6 to 8. Such an impact type crushing device is disclosed in Japanese Patent Publication No. 53-33785.

That is, in FIG. 8, inside a rotor 1 (see FIG. 6) mounted on a vertical shaft via a bearing 2 (see FIG. 6), there is a central distributor provided at the center of the rotor 1. Wing 2 rotating around 20 as the center of rotation
1, 22, and 25 are arranged, and the tip of the wing 25 has, for example, a tip wing 24 attached with a carbide tip 24a to protect the tip from wear.
are integrally fixed.

Therefore, the raw material ore (hereinafter referred to as raw material) fed from the raw material supply device 11 shown in FIG. It is sent from the blade 24 to the outlet 19 (see FIG. 7), from where it is discharged to the outside of the rotor 1.

As shown in FIG. 6, the discharged raw material collides with a dead stock 15 (or a disposed ring liner 16 (double-dashed line)) formed as a collision part inside the housing 8 that houses the rotor 1. .

The type in which a dead stock 15 is provided and the raw material collides with this dead stock 15 is used for grain size adjustment (grain shape correction) of the raw material, and the ring liner 16
The ring liner 16 is provided with a ring liner 16 to cause the raw material to collide with the ring liner 16 for crushing the raw material.

In such an impact crushing device, the rotor 1
The blades 21, 22, 25, etc. arranged in the central distributor 20 (see FIG. 6), which is the center of the rotor 1,
It is slightly curved to surround the this is,
While the input raw material passes through each of the blades 21, 22, and 25 and reaches the tip blade 24, it accumulates in this curved part, forming a so-called dead stock 17, which causes the inner wall of the rotor 1 or the base of the tip blade 24 to accumulate. The purpose is to protect materials from wear caused by collisions with raw materials.

In the rotor 1 shown in FIG. 8, two outlets 19 are provided around the rotor 1, and in order to form two dead stocks 17 accordingly, each of the blades 21, 22, 25 and the tip blade 24 are provided along the circumferential direction of the rotor 1 at an angle of about 180°.

Problems with the Prior Art By the way, as shown in FIG. 8, in the protection of the tip blade 24 by the dead stock 17, the effect is usually less effective as the raw material particles are finer due to the relationship with the angle of repose of the granular material. It becomes something big. However, the raw material actually supplied to the rotor 1 has a relatively large particle size.
Most of the particles are 20 to 80 mm in size, and when deposited as a dead stock as described above, the surface of the deposit becomes unstable.

For example, on such a deposition surface, as shown in FIG. 9, the collapse and formation of the dead stock 17 are repeated locally (the broken line and two-dot chain line in FIG. 9 indicate the deposition surface before and after the collapse of the dead stock). ,
Each time, the tip base material of the tip blade 24 is exposed.
If the base material of the tip blade 24 that was covered by the dead stock 17 is exposed, wear will occur there due to collision with the raw material.

In the tip blade disclosed in Utility Model Application No. 58-73347,
Carbide tips can be used on both the rotor center side and the rotor outer circumferential side, and the carbide tips are of the reverse type to extend the wear life. No consideration is given to preventing wear.

In the tip blade disclosed in Japanese Patent Application Laid-Open No. 59-95945,
A carbide chip is attached, for example, to the chamfered part of the tip blade, and the surface that collides with the raw material is tilted at an angle of approximately 45° with respect to the rotor center. In this case, the angle formed at the tip of the tip blade is larger than the angle of repose (approximately 40 degrees) of the raw material (dead stock), and sufficient dead stock is not formed at this tip.
For example, as shown in hatched part B in FIG.
This means that the material is exposed to the raw material due to fluctuations in the raw material, and wear occurs due to collision with the raw material. When the base material becomes severely worn, the bonding area between the chip and the base metal decreases, which may cause the chip to fall off, making it impossible to prevent wear at the tip.

In this way, conventional impact crushing equipment attaches a carbide chip to the tip of the tip blade, and this chip attempts to protect the tip of the tip blade base material from wear due to collision with the raw material. In this case, it is not possible to prevent wear at the exposed portion caused by fluctuations in the dead stock of the tip blade base material.

As shown in FIG. 9, the feedstock P located at the solid line position is discharged in the direction of arrow A without forming a dead stock, but the above-mentioned unstable layer portion of the dead stock is shown in FIG. like,
Width of approximately 1/2 particle diameter r of the above raw material P (raw material P ₁ ←→
P ₂ ), and the particle size r of this 1/2 particle size is determined by the hole size of the sieve in the sieving process, which is a pre-process of the crushing process.

Purpose of the Invention Therefore, the main purpose of the present invention is to prevent wear caused by fluctuations in dead stock in the tip blade base material subjected to dead stock,
It is an object of the present invention to provide a crushing method for extending the life of tip blades and carbide chips, and to provide a crushing device most suitable for the crushing method.

Structure of the Invention In order to achieve the above object, the main means adopted by the present invention are that the method includes a sieving step (a) in which the material to be crushed is sorted into appropriate particle sizes; a raw material supply step (b) of feeding the crushed material into a rotating rotor; and after the raw material feeding step (b), the crushed material fed into the rotating rotor is placed near the outlet of the rotating rotor. In the crushing method, the crushing step (c) comprises: depositing the crushed materials, and discharging the crushed materials outward from the outlet by centrifugal force, and crushing the materials by colliding with a collision surface around the rotating rotor. In the sieving step (a), the material to be crushed passes through the circumferential dimension of the carbide chips provided at the outlet end of the rotor center side.
The size of the holes in the sieve should be at least 1/2, and the best equipment for this method is as follows:
The materials to be crushed that have been sorted by the sieve are put into a rotor that rotates at high speed, and while the materials to be crushed are deposited near the outlet of the rotor, the materials to be crushed are moved outward from the outlet of the rotor by centrifugal force. In a crushing device that crushes chips by colliding with a collision surface around the rotating rotor, the size of the circumferential direction of the rotor center side of the carbide chips provided at the outlet end of the rotating rotor is such that A crushing device is provided in which the particle size is set to be 1/2 or more of the maximum particle size of the material to be crushed.

Function The carbide chip attached to the outlet end of the rotating rotor has a dimension in the circumferential direction on the rotor center side that is set to be 1/2 or more of the sieve hole opening dimension during the previous process.

On the other hand, the unstable layer portion of the dead stock formed at the outlet end fluctuates within a width of approximately 1/2 of the particle diameter of the raw material passing through the sieve holes during the preceding step.

Therefore, the width of the unstable layer portion of the dead stock is equal to the width of the carbide chip, and wear caused by fluctuations of the unstable layer portion of the dead stock in that portion is prevented.

Effects of the Invention According to the present invention, the surface of the carbide chip in the circumferential direction on the rotor center side can receive the unstable layer portion of the dead stock formed near the exit of the rotor.
Since the base material of the tip blade that holds the carbide tip can be prevented from being worn due to fluctuations in dead stock, the life of the tip blade and the carbide tip can be extended.

The above objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

Embodiment FIG. 1 is a schematic longitudinal cross-sectional view of an impact crushing device used in an embodiment method of the present invention, FIG. 2 is a plan view showing the internal structure of the rotating rotor in FIG. 1, and FIG. Fig. 4 is a flow diagram showing the state of flow of raw materials supplied to the impact crusher shown in Fig. 1, and Fig. 5 is a side view showing how the carbide chips are attached to the tip blade of Fig. FIG. 7 is a side view showing another state in which the hard tip is attached to the tip wing.

Note that the following example is only one specific example of the present invention, and the technical scope of the present invention is not limited by this example. Note that the same reference numerals are used to describe elements common to those described in FIG. 9.

In FIG. 1, an impact crushing device 30 includes a crushing chamber 3 formed by a housing 34 placed on a pedestal 35 and a lid 33 of this housing 34.
1. A raw material supply section 32 for supplying raw materials from above to the crushing chamber 31 is provided at approximately the center of the lid 33, as shown by arrow C, and a hopper 36 is attached to this raw material supply section 32. . Further, the pedestal 35 is formed with a discharge port 37 for dropping the raw material crushed in the crushing chamber 31 downward as shown by arrow D.

A rotor shaft 39 is disposed approximately in the center of the crushing chamber 31 and is vertically and rotatably supported by a bearing box 38 fixed to the upper surface of the pedestal 35. The lower end 30b of the rotor shaft 39 is inserted into the frame 35, and a V-pulley 40 driven by a drive device (not shown) disposed at a predetermined location is attached to the lower end 39b.

On the other hand, a hollow cylindrical rotating rotor 41 that rotates horizontally about the rotor shaft 39 is attached to the upper end 39a of the rotor shaft 39 located approximately in the center of the crushing chamber 31. .

A bracket 44 is formed on the inner surface of the side wall of the housing 34, corresponding to the height position of the raw material discharge port 43 of the rotating rotor 41. A large number of anvils 42 are attached around the anvil 41.

In this case, the rotating rotor 41 functions almost in the same way as the rotor 1 explained in FIGS. It emits outward.

That is, as shown in FIG. 2, inside the rotating rotor 41, the raw material introduced into the center of the rotating rotor 41 is distributed in the circumferential direction of the rotating rotor 41, as can be seen from the explanation in FIG. They are deposited as a dead stock 17 at appropriate angles. As the rotor 41 rotates at high speed, the deposited raw material passes through each dead stock 17 and is discharged outward from the raw material outlet 43 formed in the circumferential side wall of the rotor 41.

Inside the rotating rotor 41, in order to form each dead stock 17 as described above, the rotating rotor 41 is
Rotating rotor 4 is spaced at an angle of about 120° in the circumferential direction of
Three radially oriented partition plates 45, three side walls 46 extending in an arc shape along the periphery of the rotating rotor 41, and three tip blades 47 are arranged.

On the other hand, at the tip of each tip blade 47 of the rotating rotor 41 shown in FIG. 2, as explained in FIG. Be, carbide tip 5
0 is fixed.

In this case, as a characteristic component of this embodiment, as can be seen from FIG.
The dimension _t1 of this surface in the rotor circumferential direction, which corresponds to the center side 51 of the rotating rotor 0, is set to be 1/2 or more of the sieve hole opening dimension of the sieving process, which is the previous process of this crushing process. That is what we are doing.

Here, with reference to FIG. 4, a pre-process of such a crushing process will be explained. First of all, the raw material ore collected in large size is usually processed through the primary crushing process, for example.
The raw material is fed into a large raw material crusher 60 (geo crusher) that constitutes _K1 . Here, the large-sized raw material is crushed to the particle size required by the secondary crushing step _K2 installed downstream in the flow direction of the raw material (arrow in the figure). In this case, the secondary crushing process
As an example of the crusher that constitutes K ₂ , for example,
A device according to the first embodiment of the invention, that is, an impact crushing device 30, is provided.

Next, the first crushing process _K1 and the second crushing process
A sieving step _M1 is provided between _the raw material and the second crushing step _K2 to sieve the raw material to the particle size required by the second crushing step K2. The sieving process _M1 is usually equipped with a vibrating sieve 61, which is used to sieve out raw materials that meet the above particle size for the second crushing process _K2 . A screen with sieve hole dimensions corresponding to the above is attached.

In addition, the raw material larger than the above-mentioned particle size that remains after being sieved by this vibrating sieve machine 61 is fed back to the upstream side of the primary crushing step _K1 , and is passed through the vibrating sieve machine 61.
The crushing process is repeated until the material is large enough to pass through.

The impact crushing device 30 includes the above-mentioned sieving process M ₁
Raw materials having a predetermined particle size determined by the opening size of the vibrating sieve 61 inside are sequentially supplied.

On the other hand, for example, as shown in FIG. 3, the unstable layer portion Q (area between the two-dot chain line and the broken line in FIG. 3) of the dead stock 17 (see FIG. 2) formed in the tip blade 47 is , the width r' (corresponding to the particle diameter radius) is approximately half of the particle size of the raw materials P ₁ ′, P ₂ ′, etc. passing through the sieve opening size during the sieving process.

Therefore, when the carbide tip 50 is configured as described above, the unstable layer portion Q of the dead stock 17 falls within the rotor circumferential dimension _t1 of the carbide tip 50, and the tip of the tip blade 47 No parts are exposed. Here, wear of the base material of the tip blade 47 due to fluctuations in the unstable layer portion Q of the dead stock 17 is prevented.

In this embodiment, a surface of the carbide chip 50 opposite to the rotating rotor center side 51 and in the same circumferential direction on the rotating rotor outer peripheral side 52 is aligned with a surface in the same circumferential direction on the rotating rotor center side 51. The dimension t ₂ is set smaller than the dimension t ₁ because there is less wear compared to the other.

For example, this dimension _t2 is selected to have a thickness (approximately 3 mm) that absorbs the difference in thermal expansion during brazing and does not cause cracking during use. As a result, the carbide tip 50 is formed into a substantially triangular tapered shape, and the amount of expensive carbide tip material can be greatly reduced, making it extremely economical.

Furthermore, regarding the material of the carbide tip 50,
It is necessary to choose a material with as much wear resistance as possible, but on the other hand, the corners and edges of chips made of such materials should be protected from chipping or cracking due to collisions with raw materials, etc. I can't do without it. Therefore, by chamfering the tips, joint ends, and corners of the chips in advance and increasing the roundness at these chamfers, chipping and cracking at the corners and edges of the chips can be prevented. It is desirable to do so.

This is especially true for the tip wing 4 as shown in FIG.
When the inner side E of the tip blade 47, which is the part of the surface facing the center side 51 of the rotating rotor 7 and along its circumferential direction, is worn, the corner part F of the carbide tip 50 has the above-mentioned damage. This is based on the fact that the carbide chip will not be accidentally chipped or broken if it is rounded.

Furthermore, in this embodiment, a carbide chip 5 is provided on the inside E of the tip blade 47 where it joins with the carbide chip 50.
A cut groove 53 of an appropriate depth is formed along the joining line with 0. This works together with the chamfered portion provided at the corner F of the carbide chip 50 to prevent the concentration of shear stress (in the direction of arrow G in FIG. 3) generated at the joining line. That is.

FIG. 5 shows another state in which the carbide tip 50' is attached to the tip blade 47. Here, the carbide tip is 50'
is attached so as to face the rotor center side 51 of the tip blade 47 and protrude further toward the rotor center side than the surface along the circumferential direction thereof. The height H protruding from the tip wing 47 of this carbide tip 50' performs the same function as that performed by the above-mentioned cut groove 53 (see Fig. 3). This is to prevent concentration of shearing force generated at the joining line with the blade 47.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical sectional view of an impact crushing device used in a method according to an embodiment of the present invention, FIG. 2 is a plan view showing the internal structure of the rotating rotor in FIG. 1, and FIG. A side view showing how the hard chips are attached to the tip blade, FIG. 4 is a flow diagram showing the flow state of the raw material supplied to the impact crusher shown in the first drawing, and FIG. 5 is a side view showing how the hard chips are attached to the tip blade. FIG. 6 is a schematic vertical sectional view of the impact type crushing device which is the background of this invention, FIG. 7 is an overall perspective view of the rotor in FIG. 6, and FIG. The figure is number 6
FIG. 9 is a plan view showing the internal structure of the illustrated rotor, and FIG. 9 is a schematic explanatory view showing the aspect of dead stock in the tip blade shown in FIG. 8. Explanation of symbols, 30...Impact type crushing device, 41...Rotating rotor, 45, 46...Blade, 47...Tip blade, 5
0,50'...Carbide tip.

Claims (1)

[Claims] 1. Sieving step (a) for sorting the material to be crushed into appropriate particle sizes
and a raw material supplying step (b) in which the material to be crushed that has been sieved out in the sieving step (a) is fed into a rotating rotor; and after the raw material feeding step (b), the material to be crushed is fed into the rotating rotor. Crushing step (c) of accumulating objects to be crushed near the outlet of the rotating rotor, and ejecting the objects outward from the outlet by centrifugal force and colliding with a collision surface around the rotating rotor to crush the objects;
In the crushing method, the size of the circumferential direction of the rotor center side of the carbide chips provided at the outlet end of the rotating rotor is determined by the opening of the sieve holes during the sieving step (a) through which the material to be crushed passes. A crushing method characterized in that the size is 1/2 or more of the size. 2. The material to be crushed that has been sorted by the sieve is put into a rotor rotating at high speed, and the material to be crushed is deposited near the outlet of the rotating rotor, while the material to be crushed is pushed outward from the outlet of the rotating rotor by centrifugal force. In a crushing device that crushes chips by colliding with a collision surface around the rotating rotor, the size of the circumferential direction of the rotor center side of the carbide chips provided at the outlet end of the rotating rotor is such that the size of the chips in the circumferential direction on the rotor center side is such that 1/ of the maximum particle size of the material to be crushed
A crushing device characterized by being set to 2 or more. 3. The crushing device according to claim 2, wherein the dimension of the carbide chips in the direction of the outer circumferential side of the rotor is 3 mm or more. 4. Claim 2 or 3, wherein the carbide tip is formed in a tapered shape so that the thickness of the carbide tip gradually decreases from the rotor center side to the rotor outer peripheral side. crushing equipment. 5. The crushing device according to any one of claims 2 to 4, wherein the carbide chips are chamfered at corners as appropriate.