JPH0753246B2 - Vertical 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 fine powder, as shown in FIG. 4, a vertical pulverizer 1 provided with a rotary table and pulverizing rollers.
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 hydraulic cylinder 9 through an arm 5 and an arm 7 which are pivotally supported by a shaft 6 on a casing 15.
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 that takes out the product with the gas,
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 spiral-shaped raw material enters between the crushing roller 4 and the rotary table 3A from a direction that forms an angle with the roller axial direction and is bitten and 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.

[Problems to be Solved by the Invention] By the way, in the vertical pulverizer having the pulverizing mechanism of the raw material by the cooperation of the rotary table 3A and the pulverizing roller 4 as described above, particularly on the rotary table 3A, a slippery fluid flow is generated. In the case of pulverizing a raw material having a behavior, the raw material may be intermittently caught in the pulverizing roller, resulting in a defective product, and the pulverizing efficiency may be significantly reduced. That is, particularly when the pulverized raw material has a low water content, for example, tongue (limestone) or slag, the behavior of the raw material particles on the rotary table is fluid and slippery,
The particles tend to come apart, and for this reason, when they are supplied from the raw material chute to the center of the rotary table and reach the crushing roller, they are pressed on the rotary table with a predetermined hydraulic pressure to give the crushing force. When there is a large proportion of the material that is not scraped by the grinding roller and does not get caught in the grinding roller, or when the material is held at the jamming side of the grinding roller and there is raw material stored here, In this case, the raw material is stably bitten into the crushing roller, and the raw material is not stably and continuously bitten into the crushing roller. Further, the raw material crushed once by the crushing roller is further bitten by the next crushing roller and crushed to become a product gradually, but the raw material leaving the crushing roller is between the crushing roller and the rotary table. The gap between the particles is compressed and pops up from the crushing part that is made into a narrow gap and floats up, and the particles become scattered and become a stable layer state, and the crushing part of the next crushing roller is caught. However, there was a tendency for biting to occur poorly, and the grinding efficiency was significantly reduced due to such a cause.

Therefore, an auxiliary roller is provided on the upper surface of the outer peripheral portion of the rotary table between the crushing rollers to compress the raw material layer that is bitten into the crushing rollers to form a deaerated consolidation layer and perform crushing. It is possible to prevent the jamming failure and the accompanying reduction in the pulverization efficiency, and it is possible to reduce the vibration value (amplitude) generated in the pulverizer. However, in this case as well, there is no problem if the raw material properties and water content supplied to the crusher are constant and constant, but the raw material properties and water content change and the dynamic friction coefficient μ between the crushing roller surface and the raw material layer changes. However, if the raw material layer thickness changes, the stable state up to that point is destroyed and a large vibration suddenly occurs. In an extreme case, the operation becomes impossible, but there is no effective countermeasure against this.

[Means for Solving the Problems] In order to solve the above problems, in the vertical crusher of the present invention, a plurality of rotatable crushing rollers are arranged on the upper surface of the outer peripheral portion of the rotary table, and the rotary table central portion is provided. In a vertical crusher for crushing the raw material supplied to the crushing roller to a predetermined crushing pressure between the rotary table upper surface and the crushing roller peripheral surface, the rotary table outer peripheral surface upper surface between the crushing roller and the crushing roller. In addition, a rotatable auxiliary roller for compressing the layer of the raw material to be bitten into the crushing roller on the peripheral surface is provided, and a variable speed electric motor for driving the auxiliary roller is provided.

[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. And the auxiliary roller rotates while compressing the raw material particles with a required pressing force on the peripheral surface of the auxiliary roller, and the compressed raw material particles are brought into a dense state to form a so-called consolidation layer. It 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 pulverization and compresses the raw material particles to form a layer in which the particles are dense, that is, a so-called consolidation layer (hereinafter, the action of forming such a layer is called consolidation. In some cases, the force is so large that the pressure is considerably smaller than the pressing force of the crushing roller.

When the auxiliary roller is arranged close to the raw material catching 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 flow into the raw material catching side of the crushing roller, and the auxiliary roller is Since the ratio of the 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 compressed and the raw material particles are densely packed, and the entrainment into the crushing roller is performed more reliably. .
Of course, the raw material crushed by the previous crushing roller and the new raw material are combined and compacted by this auxiliary roller.

When the raw material properties change or the moisture content changes and the vibration value increases and it interferes with the operation, the variable speed electric motor for driving the auxiliary roller is energized to forcibly drive the auxiliary roller, Select and maintain the number of rotations at which vibration is reduced. When the vibration value decreases and the operating condition becomes stable, the forced drive of the auxiliary roller is stopped and the original condition is restored.

[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. FIG. 3 is a perspective view showing the whole vertical crusher, and FIG. 3 is a side view of an 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. An auxiliary roller 20 having a diameter smaller than that of the crushing roller 4 is arranged on the upper surface of the outer peripheral portion of the rotary table 3A between the crushing roller 4 and the crushing roller 4 at a position closer to the raw material biting side 4A of each crushing roller 4. As shown in FIG. 3, the auxiliary roller 20 is rotatably supported on a roller shaft 25 fixed to the tip of a substantially U-shaped arm 21 rotatably supported on a casing 15 by a shaft 23. Installed. A variable speed electric motor 20A for driving the auxiliary roller 20 is attached to the back surface of the arm 21. A piston rod 22a of a hydraulic cylinder 22 is rotatably connected to the lower end of the arm 21 and is connected to the hydraulic cylinder 22.
By applying a constant hydraulic pressure to the rod end chamber 22b, the compressive force of the raw material layer is applied. Hydraulic cylinder
An end of 22 opposite to the piston rod is rotatably supported by the casing 15. This compressive force is applied to the hydraulic cylinder.
This 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 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 moves to the axis 2
The auxiliary roller 20 moves up and down by being rotated about the center of rotation 3. Auxiliary roller 20 and rotary table 3A are provided under arm 21.
A gap adjuster 24 for adjusting and setting the gap between the upper surface and the upper surface is provided, and the gap adjuster 24 is fixed to the casing 15,
It is composed of a base 24b provided with a projecting screw hole and a screw shaft 24a screwed into and supported by the screw hole of the base 24b.
By making the tip end of the above contact the side end of the arm 21, it is possible to set the gap between the auxiliary roller 20 and the upper surface of the rotary table 3A.

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.

Next, the operation of the first 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 therein and the raw material which has already been pulverized by the pulverizing roller 4 into a fine powder are combined to form a coarse and dense layer 40 on the auxiliary roller 20 and the upper surface of the rotary table 3A. And the auxiliary roller 20 is rotated by being slightly lifted by the raw material layer, and the auxiliary roller 20 is compressed so that the coarse and dense layer 40 is compressed between the peripheral surface thereof and the upper surface of the rotary table 3A to form the 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 proportion (amount) of the raw material that is scraped off 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 grinding efficiency 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 shown in FIG.
Only the right half is shown.

At this time, the auxiliary roller 20 is provided with a so-called compacting effect of increasing the density of the layers of the particles by compressing the particles of the raw material, and the low pressure of the hydraulic cylinder 22 does not contribute to the pulverization of the raw material. It is given by adjusting the hydraulic pressure. The pressing force of the auxiliary roller 20 is slightly higher than the height of the auxiliary roller 20 regulated by the screw shaft 24a when the raw material is put into the gap between the auxiliary roller 20 and the rotary table 3A and is in a biting state. It is supposed to be enough to lift 20. 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.

During operation, the dynamic friction coefficient μ between the crushing roller and the raw material layer changed due to changes in the raw material properties, water content, and particle size composition, etc. Therefore, the stable operating conditions up to that point collapsed and the vibration value suddenly increased. In this case, if the variable-speed electric motor 20A of the auxiliary roller that has not been energized until then is energized to forcibly rotate the auxiliary roller and an appropriate number of rotations is selected, the vibration value decreases. After returning to the stable state in this way, the electric motor 20A is stopped for a while.

The raw material that has been bitten by the crushing roller 4 and crushed into 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 particles are scattered from the raw material discharge side 4B of the crushing roller 4 so that the particles are scattered, and the coarse and dense layer is mixed with the new raw material supplied from the raw material feeding chute 17 40, this coarse-dense layer 40 is subjected to the same compaction action as that of the previous term by the auxiliary roller 20 located next, and is further reliably caught by the crushing roller 4 located on the rotation 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.

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 made large when the size of the raw material particles is large and made small when it is small, but since it is a compaction of the layer of raw material particles, this gap is too small and the raw material particle layer is conversely disturbed. In the relatively large gap so that the auxiliary roller 20 can be smoothly bitten, 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, in the present invention, since the raw material particles can be compressed by the auxiliary roller to form a dense layer with a gap between the particles, the raw material has a high crushing force. When it tries to bite into the crushing roller that has been given a pressing force, it is less likely that it will be scraped off by the crushing roller and will pass through the side of the crushing roller and escape, and improve the biting property of the raw material into the crushing roller. Since the crushing action can be continuously performed, the crushing efficiency can be improved. It is particularly effective when pulverizing a raw material having a so-called fluidity that is slippery on a rotary table or a raw material having a small amount of attached water.

In addition, even if the vibration value temporarily increases during operation due to changes in raw material properties, water content, and particle size composition, the vibration value can be lowered by forcibly rotating the auxiliary roller and adjusting the rotation speed to an appropriate value. Since measures can be taken, it is advantageous in driving operation.

[Brief description of drawings]

FIGS. 1 to 3 show an embodiment of the present invention. FIG. 1 (A) is a plan view of the crushing roller and the auxiliary roller.
Figure (B) is a front development view of Figure 1 (A), Figure 2 is an overall perspective view of the crusher, Figure 3 is a side view of the auxiliary roller mounting portion, and Figure 4 is a vertical cross section of a conventional vertical crusher. It is a figure. 1 ... Vertical crusher, 3A ... Rotary table, 4 ... Pulverizing roller, 4A ... Material feed side, 4B ... Material discharge side, 17 ... Raw material chute, 20 ... Auxiliary roller, 20A ... … Variable speed motor 21 …… Arm, 22 …… Hydraulic cylinder, 24 …… Gap adjuster, 30 …… Compression layer, 40 …… Coarse layer.

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 for crushing between a crushing surface and a surface, a rotatable auxiliary roller for compressing the layer of the raw material bitten into the crushing roller on the peripheral surface on the outer peripheral surface of the rotary table between the crushing roller and the crushing roller, A vertical crusher having a variable speed electric motor for driving an auxiliary roller.