JPH074550B2 - Vibration level control method for vertical crusher - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a method for optimally controlling a vibration level in a vertical crusher for crushing limestone, slag, cement raw material, etc. by cooperation of a rotary table and a crushing roller.

[Prior art]

BACKGROUND ART A vertical crusher equipped with a rotary table and a crushing roller has been widely used in the past for finely crushing limestone, slag, raw materials for cement, etc. into powder. This conventional crusher is provided with a disk-shaped rotary table that is driven to rotate around a vertical axis in the lower part of a cylindrical casing, and is driven to rotate by being hydraulically pressed along the radial direction of the upper surface of the table. It has a structure in which individual crushing rollers are provided at equally divided portions in the circumferential direction of the table. The base end of the crushing roller is pivotally attached to the rotary table so that it can be moved toward and away from the rotary table, and is attached so that it can swing vertically. The crushing pressure is applied. By the way, in this type of vertical crusher, vibration occurs due to the interaction between the rotary table and the crushing roller during crushing work, but it is good if the vibration level (amplitude value) is stable, but the vibration level changes. Is a problem. It is considered that the change in the vibration level is caused by the unstable or discontinuous flow of the caught raw material in the crushing section formed by the crushing roller and the rotary table. Vibrations that are constantly generated due to the balance of the friction force of the crushing unit and the pressing force of the crushing roller can be said to be a so-called stable state, but if the flow of the raw material caught in the crushing unit becomes unstable or discontinuous due to slippage or backflow, A change in vibration level appears. From the viewpoint of raw materials, it is considered that this is due to changes in the friction coefficient due to changes in the water content, changes in the particle size distribution, and changes in the physical properties of the raw materials (mining site). When the fine powder requirement (product roughness) is low and the raw material properties may be slightly changed like a conventional crusher that grinds about 40 to 100 μm, the tolerance for fluctuations in vibration level is high. It was great. Therefore, if the vibration level fluctuates, it is dealt with by controlling the supply amount of the raw material to the crusher.

[Problems to be Solved by the Invention]

However, in a crusher that requires fine crushing with a crushing particle size of 2 to 3 μm, if the vibration level changes due to the supply of raw materials having different properties as described above, the following problems occur. Cause That is, when the vibration level increases, the crushing unit becomes unstable as described above, and the crushing efficiency decreases. Especially in the case of fine pulverization, there is a problem that not only the pulverizing ability is lowered but also the product particle size becomes coarse and the required product particle size cannot be obtained. As a result, the power consumption rate increases as the vibration level increases. In addition, the amplitude value increases due to the change of the vibration level, and from the time of stabilization (10 to 20 μm) to the time of increase (exceeding 50 μm, more than 100 μm at the maximum, one-sided amplitude), if this state is continued, There was a problem that the operation was stopped due to damage and destruction. The present invention pays attention to the above-mentioned conventional problems, and particularly in a vertical pulverizer for fine pulverization, when the vibration level reaches from the stable level to the increase level, it is quickly returned to the original stable level to improve the pulverization efficiency. It is an object of the present invention to provide a vibration level control method for a vertical crusher that prevents a decrease in power consumption and does not increase the electric power consumption rate so that stable operation can be continued.

[Means for Solving the Problems]

In order to achieve the above object, a vibration level control method for a vertical crusher according to the present invention is a crushing of a raw material supplied onto the table by a rotary table and a crushing roller which is pressed and driven to rotate on the table. In the eggplant vertical pulverizer, when the raw material was finely pulverized to about 1 to 10 μm, an auxiliary roller was provided on the upstream side of the biting portion of the pulverizing roller on the table to level the biting layer thickness and level it. The layer thickness of the layer is detected, and the vibration level of the equipment when the detected layer thickness is less than or equal to the set value is detected by a vibrometer installed in the crusher. Increase the raw material supply while increasing the rolling force to the table surface of
When the detected vibration level is higher than the set value, the reduction force of the crushing roller is decreased and the supply amount of the raw material is decreased to stabilize the vibration level. At this time, when the detection layer thickness is higher than the set value and the vibration level is high, the raw material supply amount is increased, and when the layer thickness is high and the vibration level is low, the operation may be continued as it is.

[Action]

When the powder frame raw material is powdered into a fine powder frame of, for example, about 1 to 10 μ, the powder frame properties of the raw material change and the stable state kept until then collapses, the vibration level sharply increases, and as it is If left unattended, operation may be stopped. for that reason,
In order to avoid these situations and to return to the original stable state, appropriate driving operation must be performed immediately. In the present invention, by adopting the above-mentioned configuration, the bite layer thickness between the crushing roller and the rotary table is detected by the layer thickness detecting means attached to the auxiliary roller, and when it is higher than the preset set value, Even if the crushed amount is small and the roller layer thickness is high, if the vibration level becomes low, the state is maintained and the operation is continued. On the other hand, when the vibration level is high and the roller layer thickness is too low, the rolling force of the crushing roller is reduced and the crushing amount is reduced. Then, the roller layer thickness and the vibration level are detected at appropriate time intervals, and even if the roller layer thickness is high, if the vibration level is low, the crushing roller rolling force is increased and at the same time the crushing amount is increased. Then, if the vibration level is an appropriate value, the operation is continued as a general rule. With the feedback mechanism as described above, the vibration level is adjusted by the driving operation with respect to the disturbance, and the stable operation can be continued by intermittently repeating the above detection / operation.

【Example】

Specific examples of a vibration level control method for a vertical crusher according to the present invention will be described below in detail with reference to the drawings. A vertical crusher to be subjected to vibration level control is shown in FIGS. 3 to 5. This vertical crusher is provided with a disk-shaped rotary table 12 that is driven to rotate around a vertical axis at the bottom of a cylindrical casing 10, and is driven by being hydraulically pressed along the radial direction of the upper surface of the rotary table 12. It has a structure in which a plurality of rotating crushing rollers 14 are provided at positions equally divided in the circumferential direction of the rotary table. The base end of the crushing roller 14 is pivotally attached to the rotary table 12 so that it can be brought into contact with and separated from the rotary table 12, and can be vertically swung.
Is connected to an arm 122 that can be swung around, which is further connected to a hydraulic cylinder 126 via an arm 124. Therefore, the crushing roller 14 is pressed against the upper surface of the rotary table 12 by contracting the hydraulic cylinder 126,
A crushing pressure is applied to the raw material supplied on the rotary table 12. The raw material is supplied from the charging chute 16 provided on the casing 10 onto the rotary cable 12, and the charged raw material is supplied to the biting portion with the crushing roller 14 by the rotation of the rotary table 12 and is crushed by the crushing roller.
It is crushed by receiving the pressing force from 14. Further, a small-diameter auxiliary roller 18 is arranged on the outer peripheral side upper surface of the rotary table 12 between the plurality of powder frame rollers 14 and immediately upstream of each crushing roller 14. As shown in FIG. 6, the auxiliary roller 18 has a substantially U-shaped arm pivotally attached to a horizontal shaft 20 fixed to the casing 10 side.
It is attached to the tip of 22 and can be swung in the vertical direction, so that it can be brought into contact with and separated from the rotary table 12.
22a is an air seal. The auxiliary roller 18 is rotatably supported by the arm 22 via a roller shaft 24. The lower end of the arm 22 is connected to a hydraulic cylinder 26 so that the distance between the rolling surface of the auxiliary roller 18 and the rotary table 12 can be set arbitrarily. A gap adjuster 28 for adjusting the distance between the auxiliary roller 18 and the rotary table 12 is provided in the vicinity of the hydraulic cylinder 26, which serves as a stopper function for preventing the auxiliary roller 18 from approaching the surface of the rotary roller 12 for a predetermined distance or more. It is designed to Therefore, the gap adjuster 28 controls the arm 22 so as to suppress the rotation of the arm 22.
The screw shaft 30 that can contact the back of 22 and the landing 33
Base 32 fixed to the casing 10 side and screwed to the screw shaft 30
And is adapted to adjust the clearance by screwing the screw shaft 30. In such an auxiliary roller 18, the surface of the raw material in the form of a rotary table 12 is leveled just upstream of the crushing roller 14 so as to have a predetermined layer thickness, and the raw material layer pressure to the biting portion of the crushing roller 14 is uniform. I am trying to become. In addition to such a basic configuration, the vertical crusher is provided with means for detecting the roller layer thickness leveled by the auxiliary roller 18 and supplied to the crushing roller 14. this is,
As shown in FIG. 7, a swing lever 34, which is arranged on the side of the auxiliary roller 18 and swings in conjunction with the swing motion of the roller 18, is provided. The reference surface 36 set to the above is provided, and the relationship between the two is set so as to be the relationship between the auxiliary roller 18 and the rotary table 12. That is, the swing lever
The gap L between the swing lever 34 and the reference surface 36 when the 34 swings in conjunction with the auxiliary roller 18 is set so as to match the gap between the auxiliary roller 18 and the rotary table 12. Then, the lower end surface of the swing lever 34 and the reference surface
A roller layer thickness detection sensor 38 is attached between 36 and the distance between the two is measured by this sensor 38, the gap distance between the corresponding auxiliary roller 18 and the rotary table 12 is obtained, and the raw material that matches this is determined. The roller layer thickness is detected. As the sensor 38, a general distance sensor may be used, and for example, a magnetic scale or an ultrasonic sensor may be used. Further, a vibrometer 40, which is a means for measuring the vibration level of the crusher, is provided, which is attached to the crusher main body to measure its amplitude. FIG. 1 shows a block diagram of the configuration of a control device for controlling the vibration level of the crusher. This control device is provided with a controller 42 for taking in the signal of the roller layer thickness detection sensor 38 and the measurement signal of the vibrometer 40 of the crusher. The controller 42 has a signal from the roller layer thickness sensor 38. A first comparator 44 that compares the acquisition reference signal with the acquisition reference signal, and a second comparator 46 that compares the measurement signal from the vibrometer 40 with the acquisition reference signal.
Is provided. These comparators 44 and 46 are compared with a set threshold value, and the first comparator 44 outputs "1" when the roller layer thickness is lower than the set layer thickness and the second comparator 46. In the case, when the detected amplitude value is higher than the set amplitude value, "1" is output. The output side of both comparators 44 and 46 is connected to the input terminal of the first AND circuit 48, and the output end of this AND circuit 48 is connected to the hydraulic cylinder driver 50 of the crushing roller 14, and both comparators are connected.
When the input signals from 44 and 46 are both "1", the hydraulic cylinder 52 of the crushing roller 14 is made to output a reduction signal of the pressing force. The first AND circuit 48 is also connected to the raw material feeder driver 54 via the OR circuit 55, and similarly, the output of the AND circuit 48 causes the raw material feeder 56 to output a signal for reducing the supply amount. On the other hand, a second AND circuit for inputting the output signals from the comparators 44 and 46.
58 is provided, in particular adapted to be input via the inverter 60 of the signal from the vibrometer 40. Therefore, in the second AND circuit 58, output is made when the roller layer thickness is lower than the set value and the amplitude value is lower than the set value. The output of the second AND circuit 58 is adapted to be output to the raw material feeder driver 54, but when the output of the second AND circuit 58 is obtained,
The hydraulic cylinder of the crushing roller 14 is set to activate a drive signal for increasing the pressure reduction force and also activate a drive signal for increasing the raw material supply amount to the raw material feeder 56. Further, a third AND circuit 62 is provided, which inputs the signal from the first comparator 44 through the inverter 64 and the signal from the second comparator 46. As a result, the output of the third AND circuit 62 is output when the roller layer thickness is high and the vibration level is high. The output terminal of the third AND circuit 62 is connected to the raw material feeder driver 54 via the OR circuit 55, and the feeder 56 is arranged to reduce the supply amount of the raw material when the output of the third AND circuit 62 is obtained. I am trying to start. The flow of vibration level control by such a control device
This will be described with reference to the flowchart in the figure. After starting the operation of the crusher, if there is a change in the input material in the middle, a signal from the roller layer thickness detection sensor 38 is taken in and the first comparator 44 of the control 42 sets the detection layer thickness to the set value. Compare (step 100). When the detection layer thickness is lower than the set value, the drive level comparison operation is started (step 12
0) If this is lower than the set value, the pressing force of the crushing roller 14 is increased (step 130), and the feed amount increase signal is output to the raw material feeder 56 (step 14).
0). On the contrary, when the vibration level is high, the rolling force of the crushing roller 14 is weakened (step 150), and at the same time, the supply amount of the raw material feeder 56 is slightly reduced to reduce the crushing amount (step 160). When such a process is completed, the process returns to the first step 100 after a lapse of a predetermined time, and the stabilization control is repeated. Here, in the first step 100, when the layer thickness level is higher than the set value, the vibration level is not judged (step 170), and when the vibration level is high, the step 160 is executed.
To reduce the amount of raw material supply. On the contrary, if the layer thickness is high and the vibration level is low, there is no problem, so the operation is continued, and after a certain period of time, the above process is repeated from the first step 100. By such a treatment, in the crusher in operation, due to the change in the properties of the raw material, for example, when the raw material particle size becomes small and the amplitude value becomes high, the roller layer thickness that changes due to the small particle size decreases immediately. The reduction amount of the crushing roller 14 can be reduced and the fluctuation of the vibration level can be suppressed. If the vibration level is not high even if the roller layer thickness decreases, the roll reduction amount is increased and the raw material supply amount is increased, and the crushing amount is increased while returning the roller layer thickness to the predetermined thickness. The crushing efficiency can be improved.

【The invention's effect】

As described above, according to the present invention, in the vertical crusher for crushing the raw material supplied onto the table by the rotary table and the crushing roller which is pressed on the table and is driven to rotate, When finely pulverizing to about 10μ, an auxiliary roller is provided on the upstream side of the biting part of the crushing roller on the table to level the bitten thick layer and detect the layer thickness of the leveled layer to detect the layer. The vibration level of the equipment when the thickness is less than the set value is detected by the vibrometer installed in the crusher, and if the detected vibration level is lower than the set value, the pressing force to the table surface of the crushing roller is increased. While increasing the supply amount of the raw material, and when the detected vibration level is higher than the set value, the vibration amount is stabilized by reducing the supply amount of the raw material while reducing the rolling force of the crushing roller. Vertical mill In the crusher, when the vibration level reaches the increase level from the stable level, it immediately returns to the original stable level, and the reduction of the crushing efficiency does not occur and the power consumption rate does not increase, and the stable operation is continued. The effect of being able to do is obtained.

[Brief description of drawings]

FIG. 1 is a block diagram of a vibration level control controller according to an embodiment, FIG. 2 is a flow chart of vibration level control, FIG. 3 is a plan view of a main part of a crusher, and FIG. 4 is a partial fracture of the crusher. FIG. 5 is a perspective view, FIG. 5 is a sectional view of a crushing roller portion of the crusher, FIG. 6 is a side view of an auxiliary roller, FIG. 7 is a plan view of the same, and FIG. 8 is a sectional view taken along line VIII-VIII of FIG. Is. 12 …… Rotary roller, 14 …… Grinding roller, 18 …… Auxiliary roller, 38 …… Roller layer thickness detection sensor, 40 …… Vibration meter (vibration level detecting means), 42 …… Controller, 52 …… Grinding roller Hydraulic cylinder, 56 ... Raw material feeder.

Claims (1)

[Claims] 1. A vertical pulverizer for pulverizing a raw material supplied onto the table by a rotary table and a pulverizing roller which is pressed on the table and is driven to rotate, when the raw material is finely pulverized to about 1 to 10 .mu.m. In addition, an auxiliary roller is provided on the upstream side of the biting part of the crushing roller on the table to level the biting layer thickness, and the layer thickness of the leveled layer is detected,
The vibration level of the equipment when the detection layer thickness is less than the set value is detected by the vibrometer installed in the crusher, and when the detected vibration level is lower than the set value, the pressing force to the table surface of the crushing roller is set. It is characterized in that the supply amount of the raw material is increased while increasing, and when the detected vibration level is higher than a set value, the supply amount of the raw material is reduced and the vibration level is stabilized while reducing the rolling force of the crushing roller. Vibration level control method for vertical crusher.