JPH0152058B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotary crusher, and particularly to improvements in its crushing chamber.

[Prior art] A rotary crusher inputs raw material into a crushing chamber between a concave and a mantle, crushes the raw material when the mantle closes due to the rotating motion of the mantle, and crushes the raw material on the slope of the mantle when it opens. The raw material is dropped along the line, and the next moment it closes, it is crushed a second time, and this process of crushing → falling → crushing → falling... is repeated several times, and the particle size is the same as the crushing gap and is discharged outside the machine. be.

As shown in FIG. 1, the crushing chamber of a conventional rotary crusher includes a concave 1 with a straight crushing surface 1a and a mantle 2 with a crushing surface 2a also straight. It consists of a chamber 3, a concave 1' in which the fracture surface 1a is formed by a circular arc or a series of straight lines close to a circular arc and has a bulging middle part, and a mantle 2 in which the fracture surface 2a is formed by a straight line, as shown in FIG. There is a crushing chamber 4.

In Figures 1 and 2, Dy is the average diameter in each cross section of the crushing chambers 3 and 4, and the amount of rotation (or amount of compression) of the rotating motion of the mantle 2 pivoting around the fulcrum of the upper bearing. ), the eccentric throw is Ey, the crushing gap is Sy, and the angle between the mantle 2 and the concave 1 and 1' facing it, that is, the nip angle is θy, then Dy from the top end of the crushing chamber to the bottom end,
In the case of the crushing chamber 3 in Figure 1, the changes in Ey, Sy, and tanθy are as follows: Since the inclination angle αy of the mantle 2 and the inclination angle βy of the concave 1 are constant, the nip angle θy also changes as shown by the solid line in the graph of Figure 3a. It's constant. Therefore, as shown by the solid line in the graph of FIG. 3b, the crushing chamber 3
The average diameter Dy in each cross section increases linearly,
The rate of increase is constant. Furthermore, as shown by the solid line in the graph of Fig. 3c, the eccentric throw Ey increases linearly, and the rate of increase is constant; The average diameter Dy is very small compared to the change in the fracture gap Sy shown by the solid line in the graph of Figure 3d.

On the other hand, in the case of the crushing chamber 4 shown in Fig. 2, the inclination angle αy of the mantle 2 is constant, but the inclination angle βy of the concave 1' is
Since the nip angle θy changes continuously, the nip angle θy decreases approximately linearly, as shown by the dashed line in the graph of FIG. 3a, and the rate of decrease is approximately constant. Therefore,
As shown by the dashed line in the graph of Figure 3b, the average diameter Dy in each cross section of the crushing chamber 4 increases along a quadratic curve close to a parabola that swells downward, and the rate of increase becomes larger near the lower end. ing. Also, Figure 3c
As shown by the dashed line in the graph of Figure 3, the eccentric throw Ey increases linearly as in the case of the crushing chamber 3, and the rate of increase is constant; As shown, it decreases along an upwardly bulging quadratic curve close to a parabola, and the rate of decrease becomes smaller near the lower end.

Therefore, the passage capacity Qy through which the raw materials inputted into the crushing chambers 3 and 4 are crushed and discharged to the outside of the machine is determined as follows.

Closing at any position yi of the crushing chamber 3 in Fig. 6→
If the volume that falls in one cycle from open to close is the passing volume (capacity) Qyi, then Qyi∝Dyi×Eyi/tanθyi×Sa+Sb/2×π Sa+Sb/2=Syi, so Qyi∝Dyi×Eyi/tanθyi× Syi×π ∝Dyi×Eyi×Syi/tanθyi.

Therefore, the passage capacity Qy of the crushing chambers 3 and 4 is: Qy∝Dy×Ey×Sy/tanθ.

Changes in the passage capacity Qy of the crushing chambers 3 and 4 are proportional to the formula Dy×Ey×Sy/tanθ. By substituting the changes in Dy, Ey, Sy, and tanθy shown, the changes in passing ability Qy become as shown in Figure 4 a and b. This Fig. 4 a and b shows the crushing chambers 3 and 4.
With the upper end biting diameter, lower end discharge diameter, height, and eccentric throw the same, the crushing surface shape is combined with a straight line or a curve, and the volume of each crushing chamber 3, 4 is blotted from the upper end to the lower end to examine the volume change. It is something that Note that the numerical values in the figure are an example.

As can be seen from the graph in Figure 4a, in the crushing chamber 3,
Although the passing ability increases locally at the top from the top,
After that, it decreases, and then it decreases rapidly in a straight line at the bottom. In addition, as can be seen from the graph in Figure 4b, the crushing chamber 4
In this case, the passage capacity increases gradually from the upper end, and rapidly increases linearly at the lower end.

[Problems to be Solved by the Invention] By the way, in the crushing chamber 3, the passage capacity rapidly decreases in the lower part, so the lower part tends to become overcrowded, and the processed material crushed in the upper part is crushed downward one after another. However, it is rare that the material is repeatedly dropped and discharged from the bottom end, and the processed material that has been crushed at the top falls all at once to the vicinity of the bottom end and is crushed. As a result, an overcompressed state tends to occur near the lower end, and for this reason, it is not possible to increase the crushing capacity of the object to be crushed or to increase the crushing ratio. In addition, the area near the bottom of the mantle 2 and concave 1 is locally worn.
The lifespan of the motor was shortened, and stable operation was not possible due to overload.

In addition, in the crushing chamber 4, the processed material that is crushed at the upper end is repeatedly crushed and falls downward, but since the passage capacity increases at a higher rate at the lower part, the vicinity of the lower end tends to become depopulated. The processed material crushed at the upper end falls all at once without being crushed at the lower end and is discharged from the crushing chamber 4, which reduces the crushing efficiency and causes large variations in the particle size of the crushed products. There were flaws.

Therefore, the present invention has developed a rotating system in which the passing capacity gradually increases from the upper part to the lower part, and the material to be crushed at the upper end can be sequentially crushed and dropped downward to be smoothly discharged. The purpose is to provide a crushing chamber for a dynamic crusher.

[Means for Solving the Problems] In order to solve the above problems, the crushing chamber of the rotary crusher of the present invention is such that the crushing surface of the mantle in the rotary crusher gradually moves from the upper end to the lower end. The cone cave is formed by a series of circular arcs or straight lines close to circular arcs so that the inclination angle increases, and the corresponding fracture surface of the cone cave is formed by a series of circular arcs or straight lines close to circular arcs that bulge in the middle and high parts, and between the two fracture surfaces. The crushing chamber is characterized in that the nip angle of the crushing chamber is continuously decreased from the upper end to the lower end.

[Operation] According to the crushing chamber configured as described above, the processed material crushed at the upper end is repeatedly crushed and dropped downward, and is smoothly discharged from the lower end, thereby preventing overcompression. This does not occur, and the ability to crush the material to be crushed is greatly improved, making it possible to increase the crushing ratio. In addition, local wear near the lower end is almost eliminated, extending the life of the concave and mantle and improving their yield. Furthermore, operation without overload is possible.

[Example] An example of the crushing chamber of the rotary crusher according to the present invention will be explained with reference to FIG.
It is composed of a concave 1' where a is formed by a circular arc or a series of straight lines close to a circular arc and a bulging middle part, and a mantle 2' whose fracture surface 2a is formed by a circular arc or a series of straight lines close to a circular arc. The inclination angle βy of the fractured surface 1a of the concave 1' changes continuously, and the inclination αy of the corresponding fractured surface 2a of the mantle 2' gradually increases from the upper end to the lower end. The nip angle θy of the crushing chamber 5 formed between the crushing surfaces 1a and 2a decreases along the two-dot chain line, which is close to a parabola that expands downward, as shown by the two-dot chain line in the graph of FIG. It is getting bigger near the area. Therefore, as shown by the two-dot chain line in the graph of FIG. It's getting bigger. Furthermore, as shown by the two-dot chain line in the graph of Fig. 3c, the eccentric throw Ey increases linearly as in the case of the conventional crushing chambers 3 and 4, and the rate of increase is constant, but the crushing gap Sy As shown by the two-dot chain line in FIG. 3d, it decreases along the two-dot chain line close to the upwardly bulging parabola, and the rate of decrease becomes smaller near the lower end.

However, since the passage capacity Qy of the crushing chamber 5 is proportional to the formula Dy×Ey×Sy/tanθy, the change in the passage capacity Qy of the crushing chamber 5 is expressed by the equation shown in the dashed double-dashed lines in FIGS. 3a to 3d.
By substituting the changes in Dy, Ey, Sy, and tanθy, the change in passing ability Qy becomes as shown in Figure 4c. This figure 4c shows the crushing chamber 5 for comparison with crushing chambers 3 and 4.
The upper end biting diameter, lower end discharge diameter, height, and eccentric throw are the same as those of the crushing chambers 3 and 4 shown in Figs. The plot was plotted to the bottom and the change in volume was investigated. Note that the numerical values in the figure are just examples.

As can be seen from the graph in Figure 4c, in the crushing chamber 5,
The passage capacity gradually increases from the upper end to the lower end, but the rate of increase is small.

In the crushing chamber 5 of the embodiment configured in this way,
The processed material crushed at the upper end is repeatedly crushed and fallen downward, and is smoothly discharged from the lower end.
Further, in the vicinity of the lower end of the crushing chamber 5, an overcompression state does not occur as in the conventional case, and as a result, the crushing processing capacity of the object to be crushed is greatly improved, and the crushing ratio can also be increased. Further, local wear near the lower end of the crushing chamber 5 is almost eliminated, extending the life of the concave 1' and the mantle 2' and improving their yield. Furthermore, stable operation without overload is possible.

[Effect of the invention] As can be seen from the above explanation, the passage capacity of the crushing chamber of the rotary crusher of the present invention gradually increases from the upper end to the lower end, but the rate of increase is small, so that The crushed processed material is repeatedly crushed and fallen downward, and is smoothly discharged from the lower end. Therefore, the ability to crush the material to be crushed is greatly improved, and the crushing ratio can also be increased. In addition, local wear near the lower end of the crushing chamber is almost eliminated, extending the life of the concave and mantle and improving their yield. Furthermore, stable operation without overload is possible.

[Brief explanation of drawings]

Figures 1 and 2 are partial longitudinal sectional views showing the outline of the crushing chamber of a conventional rotary crusher, Figures 3a, b,
c and d are the conventional crushing chamber and the fifth chamber shown in Figures 1 and 2.
In the crushing chamber of the present invention shown in the figure, the nip angle θy, the average diameter Dy in each cross section, the eccentric throw Ey,
Graph showing changes in fracture gap Sy, Figure 4 a, b,
c is a graph showing the passage capacity in the conventional crushing chamber shown in Figures 1 and 2 and the crushing chamber of the present invention shown in Figure 5, and Figure 5 is a schematic diagram of the crushing chamber of the rotary crusher according to the present invention. FIG. 6 is an explanatory diagram of the passing volume (capacity) at any position of the crushing chamber of the rotary crusher. 1,1'... Concave, 1a... Fractured surface, 2,
2'... Mantle, 2a... Fractured surface, 3, 4...
Conventional crushing chamber, 5... crushing chamber of the present invention.

Claims (1)

[Claims] 1 The crushing surface of the mantle in a rotary crusher is formed by a circular arc or a series of straight lines close to a circular arc so that the inclination angle gradually increases from the upper end to the lower end, and the corresponding crushing surface of the cone cave is formed at the middle and high part. The nip angle of the crushing chamber formed between the two crushing surfaces is continuously decreased from the upper end to the lower end. The crushing chamber of a dynamic crusher.