JP3166417B2 - Control method of crusher - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a pulverizer used for pulverizing a metal, a mineral, or a ceramic raw material.

[0002]

2. Description of the Related Art As a conventional example of this type of pulverizing apparatus, as shown in FIG. 3, a preliminary pulverizer 2 composed of a roller mill is installed in front of a main pulverizer 1 composed of a tube mill, for example. It is known that a separator 3 is installed at a subsequent stage of the machine 1. In this pulverizing apparatus, the raw material is supplied to the preliminary pulverizer 2 by the conveyor 4, where the raw material is coarsely pulverized to a certain degree, and then transferred to the main pulverizer 1 by the bucket elevator 5, where it is further pulverized. Then, the raw material crushed by the main crusher 1 is transferred to the separator 3 by the bucket elevator 6, where the raw material is separated into finer and coarser ones than a predetermined particle size, and the former is taken out as a product, and the latter is returned to the main crusher 1. Further pulverization is performed.

A roller mill, which is a pre-mill 2, rotates a table 21 in a horizontal plane by a driving mechanism 22, and rolls a roller 23 on the table 21 to crush the raw material supplied on the table 21. Roller 23 depending on the type of raw material and the like.
Is adjusted by the hydraulic control mechanism 24.

[0004]

In the above-mentioned conventional pulverizer, usually, a constant amount of raw material is continuously supplied to perform a steady continuous operation. There is a problem that the amount of the product to be taken out also changes when it changes. That is, even if the raw material is continuously supplied in a fixed amount at a time, if the raw material changes to one having a property that it is difficult to be crushed, the particle size of the raw material sent from the preliminary crusher 2 to the main crusher 1 becomes coarse. At the same time, the particle size of the raw material sent from the main crusher 1 to the separator 3 becomes coarse, and as a result, the amount returned to the main crusher 1 from the separator 3 increases and the amount taken out as a product decreases. Conversely, if the raw material is changed to one that is easily crushed, the amount returned from the separator 3 to the main crusher 1 decreases, and the amount taken out as a product increases.

[0005] Therefore, in order to keep the amount of the product constant in the above-mentioned conventional pulverizer, the supply amount must be increased or decreased each time in accordance with the pulverizability of the raw material. Therefore, it is not preferable because the equipment capacity depends on the equipment capacity, and the fineness of the obtained product fluctuates, and an effective improvement measure has been demanded.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and at least one of an amount of a raw material sent from a main crusher to a separator and an amount of a raw material returned from the separator to the main crusher. Is detected, and the roller rolling force of a roller mill, which is a preliminary crusher, is adjusted based on the detection result to adjust the particle size of the raw material sent from the preliminary crusher to the main crusher.

[0007]

As described above, when the crushability of the raw material changes, the particle size of the raw material sent from the preliminary crusher to the main crusher changes as it is and the particle size of the raw material sent from the main crusher to the separator. Also changes, as a result, the amount of raw material returned from the separator to the main crusher changes, the amount of product changes, and further, the supply amount to the main crusher changes, and the The amount of raw materials sent will also change. Therefore, in the present invention, by detecting the amount of raw material returned from the separator to the main crusher and the amount of raw material sent from the main crusher to the separator, it is detected that the crushability of the raw material has changed, in which case, In order to maintain the particle size of the raw material sent from the preliminary crusher to the main crusher as before, the crushing is promoted or suppressed by the preliminary crusher. Acceleration or suppression of the pulverization by the pre-pulverizer is performed by adjusting the rolling force of the roller.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a control method according to the present invention will be described below with reference to FIGS. This method uses the main pulverizer 1 in order to keep the amount of the product constant without increasing or decreasing the supply amount of the raw material even when the grindability of the raw material fluctuates in the pulverizing apparatus as shown in FIG. The amount of the raw material sent from the separator 3 to the separator 3 and the amount of the raw material returned from the separator 3 to the main crusher 1 are respectively detected, and the rolling force of the roller 23 of the roller mill as the preliminary crusher 2 is adjusted based on the detected values. By doing so, the pulverization there is promoted or suppressed, and thereby the particle size of the raw material sent from the preliminary pulverizer 2 to the main pulverizer 1 is maintained.

That is, as shown in FIG. 1, a load cell for measuring the amount (weight per unit time) of the raw material returned from the separator 3 to the main pulverizer 1 is provided in a pulverizer for carrying out the present method. 30 are installed,
The bucket elevator 6 which sends the raw material from the main crusher 1 to the separator 3 is provided with a load detector 31 for detecting the power load of the bucket elevator 6, and the detected values thereof are respectively controlled by the control device 3
2 is input.

The control device 32 sets the optimum rolling force of the roller 23 of the preliminary crusher 2 based on both of the input detection values, and outputs a control signal to the hydraulic control mechanism 24. As shown in FIG. 2, the hydraulic control mechanism 24 includes a hydraulic cylinder 40 for lowering the roller 23, a hydraulic pump 41, an accumulator 42, a switching valve 43 for switching the operation direction of the hydraulic cylinder 40, and a hydraulic cylinder 40. Solenoid proportional relief valve 4 for adjusting the working pressure
When the control signal from the control device 32 is input to the relief valve 44 and the operating pressure is adjusted, the operating pressure of the hydraulic cylinder 40 is adjusted and the pressure of the roller 23 is reduced. The power is set optimally.

In this case, the control device 32 controls the load cell 3
When the detection value of the load detector 31 is greater than 0 and the reference value, the set value of the rolling force of the roller 23 is increased. Conversely, when the detection value is lower than the reference value, the reduction of the roller 23 is reduced. Decrease the force setting.

That is, when a continuous and steady operation is performed by supplying a constant amount of the raw material, the amount returned from the separator 3 to the main crusher 1 and the amount supplied from the main crusher 1 to the separator 3 are transferred. Both the amount to be supplied and the amount of the product are kept constant, the detection values of the load cell 30 and the load detector 31 are kept constant, and the rolling force of the roller 23 of the preliminary crusher 2 is also kept constant.

However, in the case where the crushability of the raw material changes to, for example, a material that is difficult to be crushed, the particle size of the raw material sent from the preliminary crusher 2 to the main crusher 1 becomes coarser than before, and The raw material sent from the crusher 1 to the separator 3 also becomes coarse. Therefore, the number of products separated by the separator 3 decreases, the amount returned to the main crusher 1 increases, and the detection value of the load cell 30 increases. In addition, as a result, the supply amount to the main crusher 1 increases, the amount of the raw material sent to the separator 3 by the bucket elevator 6 increases, the load of the bucket elevator 6 increases, and the load detection is performed. The detection value of the detector 31 increases.

Therefore, in such a case, the control device 32 controls the operating pressure of the hydraulic cylinder 40 so as to increase the rolling force of the roller 23, thereby promoting the pulverization in the preliminary pulverizer 2 and The raw material to be sent to the mill 1 is prevented from becoming coarse, and the raw material having the same size as before is sent to the main crusher 1. As a result, the particle size of the raw material sent from the main crusher 1 to the separator 3 is maintained at the same level as before, the increase in the amount returned from the separator 3 to the main crusher 1 is prevented, and the raw material is taken out. There is no decrease in the amount that is consumed.

Conversely, if the raw material is changed to one that is easily pulverized, the particle size of the raw material sent from the pre-pulverizer 2 to the main pulverizer 1 becomes finer than before, and the main pulverizer 1 separates the raw material from the separator. Since the particle size of the raw material sent to the feeder 3 becomes finer, more of the raw material is separated by the separator 3 and the amount returned to the main pulverizer 1 is reduced, and the supply amount to the main pulverizer 1 is smaller than before. As a result, the load of the bucket elevator 6 decreases, and the load cell 3
0 and the detection value of the load detector 31 decrease. in this case,
The control device 32 controls the operating pressure of the hydraulic cylinder 40 so as to reduce the rolling force of the roller 23, thereby suppressing the pulverization in the preliminary pulverizer 2 and preventing the raw material sent to the main pulverizer 1 from becoming finer. The raw material having the same particle size as before is sent to the main crusher 1, whereby the amount of the product is maintained and the fineness of the product is stabilized.

As described above, the amount of the raw material returned from the separator 3 to the main crusher 1
And the amount of the raw material sent to the pre-crusher 2 is detected by the load cell 30 and the load detector 31, respectively.
By promoting or suppressing the crushing there by adjusting the rolling force of the material, it is possible to reliably prevent the amount of product taken out from fluctuating even when the crushability of the raw material changes. The product can be obtained and the fineness of the product can be stabilized, and there is no need to adjust the supply amount according to the properties of the raw materials, so that a steady and efficient continuous operation can be performed.

In the above embodiment, the amount of the raw material returned from the separator 3 to the main crusher 1 is detected by the load cell 30. However, the load cell is not limited to the load cell as long as the amount of the raw material can be detected. May be employed. Further, in the above-described embodiment, the amount of the raw material sent from the main crusher 1 to the separator 3 is detected by the load detector 31 of the bucket elevator 6. However, another type of detector may be used. Alternatively, a transfer mechanism other than the bucket elevator 6 may be employed.

Further, in the above embodiment, both the amount of the raw material returned from the separator 3 to the main crusher 1 and the amount of the raw material sent from the main crusher 1 to the separator 3 are detected. Will not detect both
It is also possible to detect only one of them and control based on the detection result. However, as in the above embodiment, 2
If data is taken from a location, more precise control can be performed by complementing them as necessary, and it is preferable to do so.

[0019]

As described above, the present invention detects at least one of the amount of raw material returned from the separator to the main crusher and the amount of raw material sent from the main crusher to the separator, and based on the detected amount, By adjusting the roller rolling force of the preliminary crusher, the particle size of the raw material sent from the preliminary crusher to the main crusher is adjusted, so if the crushability of the raw material changes, crushing by the preliminary crusher The particle size of the raw material sent to the main crusher after being accelerated or suppressed can be maintained at the same level as before, so that a certain amount of product can always be obtained and a product of a certain fineness regardless of the nature of the raw material Is obtained, and there is an effect that a steady and efficient continuous operation can be performed.

[Brief description of the drawings]

FIG. 1 is a system diagram of a pulverizing apparatus for carrying out the method of the present invention.

FIG. 2 is a system diagram of a hydraulic control mechanism for adjusting a rolling force of a roller in the apparatus.

FIG. 3 is a system diagram showing a conventional example of a crusher.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main crusher 2 Preliminary crusher (roller mill) 3 Separator 6 Bucket elevator 23 Roller 24 Hydraulic control mechanism 30 Load cell 31 Load detector 32 Control device 40 Hydraulic cylinder 41 Hydraulic pump 42 Accumulator 43 Switching valve 44 Relief valve.

Claims (1)

(57) [Claims] 1. A preliminary crusher comprising a roller mill is installed at a stage preceding the main crusher, and a raw material sent from the main crusher is separated into a product and a raw material to be returned to the main crusher at a stage subsequent to the main crusher. A method of controlling a crushing apparatus having a separator for detecting at least one of an amount of a raw material sent from the main crusher to the separator and an amount of a raw material returned to the main crusher from the separator. A method of controlling a crushing device, comprising: adjusting the rolling force of a roller in the preliminary crusher based on the detection result to adjust the particle size of the raw material sent from the preliminary crusher to the main crusher.