JPH074546B2 - Rigid crusher - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vertical crusher for crushing raw materials such as limestone, slag, and cement raw material in cooperation with a rotary table and a crushing roller.

[Prior Art] As a kind of pulverizer for pulverizing raw materials such as limestone, slag, and cement raw material into powder, as shown in FIG. 4, a vertical pulverizer 1 equipped with a rotary table and pulverizing rollers 1
Is widely used. This type of crusher has a disk-shaped rotary table 3A which is driven by a speed reducer 2 by a motor 2A at a lower portion of a cylindrical casing 15 and rotates at a low speed, and a hydraulic pressure is applied to a portion which equally divides an outer peripheral portion of an upper surface thereof in a circumferential direction. And a plurality of crushing rollers 4 that are driven to rotate by being pressed against each other.

The crushing roller 4 has a casing 15 and a hydraulic cylinder 9 via an arm 5 and an arm 7 which are pivotally supported by a shaft 6 at the time of swinging.
Is connected to the piston rod 10 of the hydraulic cylinder 9
The crushing roller 4 by rotating the rotary table.
Pressing on 3A gives crushing pressure to the raw material. 3B is a dam ring provided on the outer peripheral edge of the rotary table 3A for adjusting the raw material layer pressure, 14 is a gas blowing annular space passage around the rotary table 3A, 13 is a rotary separator for classifying the raw material crushed by blades 13A, 16 Is an outlet for taking out the product together with gas, and 17 is a raw material charging chute.

In such a vertical crusher, the raw material supplied to the central portion of the rotary table by the raw material chute 17 is rotated when sliding on the rotary table 3A by the centrifugal force in the radial direction of the table due to the rotation of the rotary table 3A. The table 3A receives a force in the direction of rotation and slides with respect to the table 3A to perform rotation somewhat slower than the number of rotations of the table 3A. The above two forces, that is, the force in the radial direction and the force in the rotation direction are combined, and the raw material moves to the outer peripheral portion of the rotary table 3A in a spiral trajectory on the rotary table 3A. In this peripheral part,
Since the rollers are pressed against each other and rotate, the raw material in which the spiral is drawn enters between the crushing roller 4 and the rotary table 3A from a direction forming an angle with the roller axial direction, is bitten into the particles, and is crushed.

On the other hand, gas such as air or hot air is guided to the base of the casing 15 by a duct, and this gas blows up from the annular space portion 14 between the outer peripheral surface of the rotary table 3A and the inner peripheral surface of the casing. As a result, the pulverized fine powder is entrained in the gas and rises in the casing 15, and is subjected to the classification action by the blades 13A of the separator 13 located at the upper portion,
The product having a predetermined particle size is discharged together with the gas from the discharge port 16 and sent to the next step.

By the way, the object to be crushed supplied to the crusher is rarely crushed to the fine grain size required by this crusher even if it is subjected to the crushing action by the crushing roller once, and it falls to the center of the rotary table. Since all the crushed objects are not bitten by the crushing roller, even if the powder and granules reaching the outer peripheral end of the rotary table ride on the hot air flow rising from the annular space and rise, By the time it reaches the separator installed in the upper part, it falls on the way depending on its particle size, or is classified and eliminated by the separator and returned to the rotary table.

For this reason, measures have been taken such as providing a coarse powder conduit 100 in the mill for positively returning the coarse powder after separator classification onto the rotary table.

In this way, the material to be pulverized, which is supplied momentarily into the pulverizer, rises from the rotary table to the separator or reaches the rotary table until it reaches the desired fine grain size of the final product and flows out of the pulverizer. To a separator, the particles are gradually crushed many times from the middle to reach a desired particle size.

[Problems to be Solved by the Invention] In the conventional vertical crusher as described above, the crushing conduit as described above is introduced to the biting side of the crushing roller and crushed by the crushing roller together with the raw material for new feed. As a result, the vibration value of the mill increased, and the smooth crushing action could not be performed. In severe cases, the equipment might be damaged or the operation could not be continued.

This is because the coarse powder after classification in the coarse powder conduit is 1/10 to 1/1000 times finer than the raw material particle size of New Feed and has a large bulk specific gravity and a large specific surface area. The reason is that the rate becomes large, and it was necessary to perform some method to integrally consolidate the raw material and the coarse powder of New Feed to purge (exclude) the air present in the raw material.

The above phenomenon corresponds to the experience in actual operation that the mill vibration is small when the product grain size is large (when a coarse product is obtained), and the mill vibration occurrence frequency and the mill vibration value increase when the product grain size becomes small.

[Means for Solving the Problems] In order to achieve the above object, the vertical crusher of the present invention has a plurality of rotatable crushing rollers arranged on the upper surface of the outer peripheral portion of a rotary table and supplies the crushing roller to the central portion of the rotary table. In the vertical pulverizer provided with a classifier at the top of the pulverizer, which classifies the pulverized raw material by applying a predetermined pulverizing pressure to the pulverizing roller to pulverize between the rotary table upper surface and the peripheral surface of the pulverizing roller, On the upper surface of the outer peripheral portion of the rotary table between the crushing rollers, a rotatable auxiliary roller for compressing the layer of the raw material for biting into the crushing rollers on the peripheral surface is disposed, and the coarse powder after classification in the classifier is provided. The discharge port of the coarse powder conduit for returning to the crushing roller is arranged on the biting side of the auxiliary roller.

[Operation] The raw material supplied from the raw material feeding chute to the upper surface of the central part of the rotary table draws a spiral locus on the rotary table and moves to the outer peripheral side of the rotary table to reach the biting side of the auxiliary roller, and the auxiliary roller and the rotary table. When flowing in between, the auxiliary roller compresses the raw material particles with a required pressing force on the peripheral surface while rotating, and each compressed raw material particle is in a dense state, so-called, It is said that This consolidation layer reaches the biting side of the crushing roller by the rotation of the rotary table, and even if the crushing roller is given a high pressing force as the crushing force, it is bitten with a higher probability and continuous crushing is performed. Further, the raw material particles that are crushed by the crushing roller and become finer and flow out from the non-meshing side of the crushing roller as a so-called coarse and dense layer are subjected to a similar compaction action by this auxiliary roller and crushed to the next position. It is highly likely to be bitten into the rollers and crushed efficiently. The pressing force of the auxiliary roller in the direction of the upper surface of the rotary table does not contribute to the crushing, but compresses the raw material particles to form a layer in which the particles are closely packed, so-called, (Hereinafter, the action of forming such a layer may be referred to as consolidation.) The force is such that it is formed, and a force far smaller than the pressing force of the crushing roller is sufficient.

When the auxiliary roller is arranged close to the raw material injecting side of the crushing roller, new raw material from the raw material charging chute guided to the outer peripheral portion of the rotary table is less likely to directly flow into the raw material injecting side of the pulverizing roller. Since the ratio of the raw material flowing into the raw material entrapment side increases, the new raw material is less likely to disturb the consolidation layer in which the raw material particles are compacted by the auxiliary roller and the raw material particles are densely packed, and the entrainment into the crushing roller is performed more reliably. Be done. Of course, the raw material crushed by the previous crushing roller and the new raw material (new feed) are combined and compacted by this auxiliary roller.

The coarse powder after being classified by the separator is also introduced into the coarse powder pipe arranged immediately before the auxiliary roller is engaged with the discharge port, and is also compacted by the auxiliary roller together with the raw material for the new feed.

As a result, the auxiliary roller can form a dense layer with a constant thickness, so that the natural frequency of the raw material layer can be maintained at a certain natural frequency that has passed through the resonance range to prevent vibration. This is the second main function of the auxiliary roller.

In this way, the powder layer compacted by the auxiliary roller is efficiently crushed by the crushing roller arranged in the subsequent stage of the auxiliary roller, and the natural frequency is maintained so that the raw material layer is kept at a constant height and vibration does not easily occur. I have to.

[Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings.

1 to 3 illustrate an embodiment of the present invention.

In FIG. 1, FIG. 1 (A) is a plan view showing an arrangement state of a crushing roller and an auxiliary roller on a rotary table, FIG. 1 (B) is a front development view of FIG. 1 (A), and FIG. The figure is a perspective view showing the entire vertical crusher (however, the coarse powder conduit 100 is omitted), and FIG. 3 is a side view of the auxiliary roller mounting portion. In the figure, the same parts as those in FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIGS. 1 and 2, two crushing rollers 4 are arranged on the upper surface of the outer peripheral portion of the rotary table 3A at positions symmetrical to the center of the rotary table 3A. 4 are located on the upper surface of the outer peripheral portion of the rotary table 3A while the auxiliary rollers 20 each having a diameter smaller than that of the crushing roller 4 are arranged at a position close to the raw material biting side 4A of each crushing roller 4. As shown in FIG. 3, the auxiliary roller 20 is rotatably supported by a roller shaft 25 fixed to the tip of a substantially U-shaped arm 21 rotatably supported by a shaft 23 on a casing 15. Has been. A piston rod 22a of a hydraulic cylinder 22 is rotatably connected to the lower end of the arm 21. By applying a constant hydraulic pressure to the rod end chamber 22b of the hydraulic cylinder 22, a compression force is applied to the raw material layer. An end of the hydraulic cylinder 22 on the side opposite to the piston rod is rotatably supported by the casing 15. This compression force is performed by adjusting the hydraulic pressure by a pressure adjusting valve (not shown) attached to the hydraulic line connected to the rod end chamber 22b of the hydraulic cylinder 22. An accumulator is connected to this hydraulic line, and the rod end chamber 22b of the hydraulic cylinder 22 is kept at a constant pressure. By expanding and contracting the piston rod 22a of the hydraulic cylinder 22, the arm 21 is rotated about the shaft 23, and the auxiliary roller 20 moves up and down. A gap adjuster 24 for adjusting and setting the gap between the auxiliary roller 20 and the upper surface of the rotary table 3A is provided below the arm 21, and the gap adjuster 24 is fixed to the casing 15 and has a screw hole. With the installed base 24b,
A screw shaft 2 screwed into and supported by the screw hole of the base 24b
4a, and the gap between the auxiliary roller 20 and the upper surface of the rotary table 3A can be set by bringing the tip of the screw shaft 24a into contact with the side end of the arm 21.

When the weight of the auxiliary roller 20 is sufficient as the compression force of the raw material layer, the hydraulic cylinder 22 is set free.

Further, at the upstream side of the auxiliary roller 20, the discharge port 1 of the coarse powder conduit 100
00a is arranged so that the coarse powder after being classified by the separator 13 is guided to the biting side of the auxiliary roller 20.

Next, the operation of the embodiment having such a configuration will be described.

The raw material supplied from the raw material feeding chute 17 to the upper surface of the central portion of the rotary table 3A receives the centrifugal force of the rotary table 3A and draws a spiral locus on the rotary table 3A to move to the outer peripheral side of the rotary table. As shown in (B), most of the raw materials, the raw material made into fine powder already crushed by the pulverizing roller 4 and the fine powder raw material introduced by the coarse powder conduit 100 are combined into a coarse and dense state. Flows into the gap between the auxiliary roller 20 and the upper surface of the rotary table 3A as a layer 40, and the auxiliary roller 20 rotates between the peripheral surface and the upper surface of the rotary table 3A while rotating while being slightly lifted by the raw material layer. The coarse layer 40 is compressed into the degassed consolidated layer 30. This compaction layer 30 reaches the biting side 4A of the pulverization roller 4 by the rotation of the rotary table 3A, and here the raw material particles are not in a scattered state but in a compaction layer in a dense state, so that the pulverization roller 4 is Even if a pressing force as a high crushing force is applied and a narrow gap is formed between the rotary table 3A and the upper surface of the rotary table 3A in order to obtain a predetermined product grain size, the crushing roller 4 is more reliably bitten into the crushing roller 4, The ratio (amount) of the raw material which is scraped by the crushing roller 4 and does not bite into the crushing roller 4 and flows through the side portions thereof is reduced. Therefore, the crushing effect is improved. In addition, in FIG. 1 (A), F is a moving locus of the raw material particles, C is a catching portion (crushing portion) between the roller and the rotary table 3A, and the moving locus of the raw material particles is the right half of the drawing. Only showing.

At this time, the auxiliary roller 20 is given a so-called compaction effect of compressing the particles of the raw material to purge the interparticle gas to increase the density of the layer of the particles, so that the auxiliary roller 20 has By adjusting the hydraulic pressure of the hydraulic cylinder 22, a low pressure that does not contribute to the pulverization of the raw material of 20 to 1/10 is provided. The pressing force of this auxiliary roller 20 is
Auxiliary roller 2 regulated by screw shaft 24a when the raw material is charged into the gap between 20 and rotary table 3A and is biting
The force is set so that the auxiliary roller 20 can be lifted a little more than the height of 0. The pressing force of the auxiliary roller 20 may be much smaller than the pressing force as the crushing force of the crushing roller 4, and if its own weight is sufficient, hydraulic pressure need not be applied. The pressing force of the auxiliary roller changes depending on the size of the raw material particles and the degree of adhered water. For example, when the diameter of the raw material particles is small, the pressing force may be small.

The raw material that has been bitten by the crushing roller 4 and crushed into a small size receives the rotating force of the rotary table 3A and the crushing roller 4 while receiving the compressive force in the narrow gap between the crushing roller 4 and the rotary table 3A. , The raw material discharge side 4B of the crushing roller 4 vigorously ejects the particles so that the particles are in a disjointed state, and is mixed with the new raw material supplied from the raw material feeding chute 17 to form a coarse and dense layer. 40, the coarse and dense layer 40 is subjected to the same consolidating action as described above by the auxiliary roller 20 located next, and is surely bitten by the crushing roller 4 located on the rotational direction side of the rotary table 3A. It is crushed and crushed, and it becomes closer to the product particle size. Then, since the auxiliary roller 20 is positioned close to the meshing side 4A of the crushing roller 4, the consolidation layer 30 that has come out of the auxiliary roller 20 is moved from the raw material charging chute 17 to the rotary table 3A.
Since the addition of new raw material supplied to the upper part is reduced, the consolidated state is less likely to be disturbed, the consolidated layer 30 is stable, and the crushing roller 4
Will be more reliably bitten into. Although the diameter of the auxiliary roller 20 is smaller than that of the crushing roller 4 in this embodiment, generally, when the particle diameter of the raw material particles is small, the diameter of the auxiliary roller 20 may be small. In addition, when the particle diameter of the raw material particles is large, the diameter is increased so that the compaction effect can be imparted according to the particle diameter of the raw material particles.

Further, the gap between the auxiliary roller 20 and the upper surface of the rotary table 3A is set by moving the screw shaft 24a of the gap adjuster 24 in and out. This gap is increased when the raw material particle size is large, and is small. However, since it is intended to consolidate the layer of raw material particles, this gap is not too small and the raw material particle layer is not disturbed conversely, and it is relatively smooth so as to be smoothly bitten by the auxiliary roller 20. In a large gap, for example,
When the raw material particle size is 5 mm or less and the gap between the crushing roller 4 and the rotary table 3A is 5 to 10 mm, an auxiliary roller
The gap between 20 and the turntable 3A is set to 40 to 60 mm.

[Effects of the Invention] As is clear from the above description, the separator (classifier)
The coarse powder after classification is guided by a coarse powder conduit with a new feed material in advance to form a consolidated layer that has been depressurized with an auxiliary roller and then crushed with a crushing roller, so there is little vibration and stable Since such continuous movement can be performed for a long period of time, crushing efficiency is improved and productivity is increased.

Also, compared with a crusher that does not use a coarse powder conduit, the classified coarse powder can be quickly made into the required fine powder, which has the effect of improving the pulverization efficiency. A cost reduction effect can also be expected.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention, FIG. 1 (A) is a plan layout view of a crushing roller and an auxiliary roller, and FIG. 1 (B) is shown in FIG. 1 (A). Fig. 2 is a front development view, Fig. 2 is an overall perspective view of the crusher, Fig. 3 is a side view of an auxiliary roller mounting portion, and Fig. 4 is a vertical sectional view of a conventional vertical crusher. 1 ... Vertical crusher, 3A ... Rotary table, 4 ... Crushing roller, 4A ... Raw material side, 4B ... Raw material discharge side, 17 ... Raw material chute, 20,50 ... Auxiliary roller, 21 ... Arm, 22 ... Hydraulic cylinder, 24 ... Gap adjuster, 30 ... Consolidation layer, 40 ... Coarse layer, 100 ... Coarse powder conduit.

Claims (1)

[Claims] 1. A plurality of rotatable crushing rollers are arranged on the upper surface of the outer peripheral portion of a rotary table, and a predetermined crushing pressure is applied to the raw material supplied to the central portion of the rotary table to apply a predetermined crushing pressure to the upper surface of the rotary table and the peripheral surface of the crushing roller. In a vertical crusher equipped with a classifier at the top of the crusher for crushing between the surface and the crushed fine powder, a crushing roller is provided on the outer peripheral surface of the rotary table between the crushing roller and the crushing roller. A rotatable auxiliary roller that compresses the layer of the entrapped raw material on the peripheral surface is arranged, and the discharge port of the coarse powder conduit for returning the coarse powder after classification in the classifier to the crushing roller is on the interlocking side of the auxiliary roller. Vertical crusher installed.