JPS6388055A - Vertical crusher - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a vertical pulverizer, and particularly to a vertical pulverizer equipped with a rotary classifier capable of classifying fine powder.

[Prior Art] Vertical pulverizers have been conventionally used as pulverizers for pulverizing coal, cement, and the like.

This vertical crusher consists of a disk-shaped rotary table that is driven by a motor with a reducer and rotates at a low speed in the lower part of a cylindrical casing, and a part that divides the upper surface of the rotary table equally in the circumferential direction, which is pressed by hydraulic pressure or the like. A classifier is installed in the upper part of the casing.

In this vertical crusher, powder as a raw material is supplied to the center of the rotary table through a supply pipe, and when the table rotates, the powder is subjected to centrifugal force in the radial direction of the table, and as it slides on the table, it is rotated by the table in the direction of rotation. It receives the force, slides between it and the table, and rotates somewhat slower than the table rotation speed.

The above two forces, that is, the forces in the radial direction and the force in the rotational direction are combined, and the powder moves to the outer periphery of the rotary table while drawing a spiral trajectory on the table. Since the roller is in pressure contact with this outer periphery and is rotating, the particles with spiral lines enter from a direction forming a certain angle with the axial direction of the roller between the roller and the rotating table and are bitten. Smash.

On the other hand, hot air is guided to the base of the casing by a duct, and as this hot air blows up from the annular space between the outer circumferential surface of the rotary table and the inner circumferential surface of the casing, the fine powder is dried and removed from the casing. The air rises inside the air and is discharged as a mixture with hot air through the outlet and sent to the next process.

By the way, it is rare for the material to be crushed supplied to the crusher to be crushed into the fine powder particle size required by this crusher by being subjected to the crushing action by the crushing rollers only once, and the material may fall to the center of the rotary table. Not all of the crushed material is bitten by the crushing rollers, so even if the powder and granules that do not reach the outer edge of the rotary table rise up on the hot air current blown up from the annular space, they will not be able to reach the crusher. By the time the particles reach the classifier installed at the top, depending on their particle size, they may fall or be classified and rejected by the classifier and returned to the rotary table.

In this way, the material to be crushed that is constantly fed into the crusher rises from the rotary table to the classifier or rotates until it reaches the desired fine powder particle size that will become the final product and flows out of the crusher. The particles fall from the middle of the ascending path from the table to the classifier over and over again until they are gradually pulverized to the desired particle size.

One type of classifier that is widely used is a rotary classifier. This rotary classifier is configured such that a rotating shaft is provided in the vertical direction, and a plurality of rotating blades are fixedly fixed to the rotating shaft at an equal pitch, and are rotated together with the shaft at an arbitrary number of rotations. As is well known in this rotary classifier, the blades rotate together with the rotating shaft, thereby separating fine particles from the airflow that passes between the blades and flows into the classifier.

[Problems to be solved by the invention] In conventional rotary classifiers, particles flowing between the rotating blades easily pass between the rotating blades, even if they have a relatively large diameter. In the installed vertical pulverizer, the product obtained by pulverization had a coarse particle size distribution.

In this conventional classifier, it is possible to shift the classified particle size to fine particles by increasing the rotation speed of the blades, but this increases the cost of rotational power and increases the pressure loss of the classifier, so it is necessary to use a suction fan. Power costs also increase.

[Means for Solving the Problems] The present invention provides a vertical crusher equipped with a rotary classifier, in which the outer edge of the rotary blade of the classifier is provided with an end that obliquely intersects with the radial direction of the classifier. The present invention is characterized in that the plate is fixed at an angle such that the front edge side of the end plate in the rotational direction is located closer to the center of the classifier than the rear edge side.

[Function] In the rotary classifier of the present invention, end plates are provided at the outer edges of the rotary blades at a predetermined angle, and the flow path between the rotary blades is curved. Therefore, among the particles that tend to flow between the rotating blades along with the airflow, particles with a large diameter collide with this end plate and are blocked from passing. Thereby, the classified particle size can be shifted to the finer particle side without increasing the rotation speed of the classifier, and fine pulverization can be easily performed.

[Example] FIGS. 1 and 2 show a vertical crusher according to an example of the present invention, FIG. 1 is a schematic vertical cross-sectional view of the entire vertical crusher, and FIG. A sectional view illustrating the configuration of a rotating blade,
FIG. 3 is an enlarged view of the main part of FIG. 2.

In FIG. 1, a crusher 1 includes a rotary table 3 which will be described later.
The casing 20 includes a cylindrical lower casing 20a fixed to the floor, and an inner cone 20c with a circular cross section drawn in the middle. Middle part casing 2
0b, and an upper casing 20d joined to the upper end thereof.

A reducer 2 with a motor is disposed in the center of the lower casing 20a, and a rotary table 3 formed in a disc shape is attached to the output shaft facing upward. It is driven and rotates clockwise when viewed from above in FIG. A plurality of roller boss arms 5 are arranged at the upper outer peripheral end of the rotary table 3, and each of the roller boss arms 5 has a conical head-mounted crushing roller 4 pivotally attached to its lower end, which is pivoted in a substantially horizontal state. ing.

A pressure frame 6 having an annular shape is fixed to the upper surface of the upper inner peripheral end of the roller boss arm 5 by means such as bolt tightening. It is integrally formed and mounted on the upper surface of the rotary table 3.

On the other hand, the upper outer peripheral end of each roller boss 5 is rotatably connected to a hydraulic cylinder 10 via a connecting rod 8, a turnbuckle 9, and a cylinder rod 10a by a pin 7 and a fork end 7a, and the lower end of the hydraulic cylinder 10 is rotatably connected to a hydraulic cylinder 10 via a connecting rod 8, a turnbuckle 9, and a cylinder rod 10a. With the bin 11 and the rotating seat 12, the base plate 1
It is connected to 3.

Each crushing roller 4 is connected to a roller boss 5 via a roller shaft 4a.
The rotary table 3 is rotatably supported by a shaft, and its circumferential surface is in contact with the outer peripheral surface of the upper end of the rotary table 3, so that it can be rotated in accordance with the rotation of the rotary table.

A rotary classifier 15 is installed above the center of the rotary table 3. This classifier 15 includes a plurality of rotating blades 27 supported by a rotating shaft 23 made of a cylindrical tube via a stay 25 and an inverted conical bottom i28. Note that the rotating shaft 23 is supported by the refined powder discharge pipe 22 via a bearing 24. Although not shown, a drive device for the rotating shaft 23 is also installed. Reference numeral 16 is a raw material supply pipe;
It is inserted through the rotating shaft 23.

Therefore, in this rotary classifier 15, the rotary blade 2
An end plate 3o that obliquely intersects with the radial direction of the classifier is placed on the outer edge of 7, and the front edge side 30a of the end plate 30 in the rotational direction is on the rear edge side 3.
It is fixedly installed at an inclined position located closer to the center C of the classifier than 0b.

An annular hot air passage 21 is provided below the outer periphery of the rotary table 3 and is connected to a hot air generator through a duct 18. An annular space 14 is defined by an inner circumferential wall 14a and an outer circumferential wall 14b. In this annular space 14, a plurality of plate-shaped blades 14c are arranged and fixed at equal intervals around the circumference while maintaining a required inclination angle with respect to the horizontal plane.

In addition, at the bottom of the hot air passage, there is a discharge chute 1 that temporarily discharges foreign objects during crushing and excess crushed materials in the event of overload.
9 is installed and can be taken out from a discharge door 19b which is rotatable around a rotation pin 19a.

The operation of the crusher configured as above will be explained next.

After starting the reducer 2 with a motor to rotate the rotary table 3, the material to be crushed is supplied from the supply pipe 16 to the center of the upper surface of the rotary table 3 while maintaining airtightness by a conveyor such as a conveyor (not shown). Then, due to the rotation of the rotary table 3 and the centrifugal force of the rotation, the object to be crushed draws a spiral trajectory and moves toward the outer periphery of the rotary table 3. Since the crushing roller 4 is rotating on the outer periphery of the rotary table 3,
Most of the moved material to be crushed is caught between the crushing roller 4 and the rotary table 3, and is crushed into fine powder by compression, impact, and shearing action. This fine powder, coarse particles and intermediate particles that are not bitten by the crushing roller 4 and come off the periphery of the rotary table 3 fall into the annular space 14, but at this time, they are sent through the duct 18 by the hot air generator. Since the hot air blows up from the hot air passage 21 to the annular space 14,
These fine powders and intermediate particles rise inside the mill along with the hot air. The fine powder and intermediate particles that have risen flow from the side of the classifier 15 into the classifier 15 through between the blades 27 . The classifier 15 is rotated at a predetermined speed (arrow R), and when the particles pass between the blades 27, the particles are transferred to the end plate 30.
It collides with the blade 27 and falls along the blade 27.

Since the passage between the blades 27 is bent by the end plate 27, small-diameter particles can pass between the blades 27 relatively easily while changing the flow direction with the airflow, but medium-diameter particles and Particles with a larger diameter than the end plate 30 or the blade 27
collides with and falls. Therefore, even if the rotation speed is the same as before, the classified particle size shifts to the finer particle side.

In this way, the fine powder that has been classified by the classification action of the classifier and has reached the desired fine particle size is sent to the next process via the discharge pipe 22.

In addition, in the present invention, the intersecting angle θ between the end plate 30 and the blade 27 is
Although it varies depending on the classification particle size, it is preferably about 10° to 60°.

In the embodiments described above, the blades of the classifier are provided in the vertical direction, but blades that taper downward, or blades that taper downward only at the lower part may also be used.

The present invention can also be applied to various types of vertical crushers other than those shown in the figures.
For example, in the illustrated vertical crusher, the liner of the rotary table may be of an inclined type or a dish type instead of a flat type, and the corresponding crushing rollers may be changed to a type that is compatible with these types.

[Effects of the Invention] As is clear from the above description, according to the present invention, the classified particle size can be shifted to the finer particle side without increasing the rotation speed of the rotary classifier, and fine pulverization can be achieved. Therefore, it is extremely suitable for grinding charcoal, talc, colloidal cement, etc.

Further, according to the present invention, even if the rotational speed of the classifier is lowered, classification comparable to that of conventional classification is possible, and fan power can be reduced due to the reduction in classification pressure loss.

Furthermore, the cost of rotating power for classification is also reduced.

[Brief explanation of the drawing]

FIG. 1 is an overall schematic sectional view showing a vertical crusher incorporating a rotary classifier according to an embodiment of the present invention, and FIG. 2 is an explanatory diagram of the configuration of the rotary blades of the rotary classifier shown in FIG. be. FIG. 3 is an enlarged view of the main part of FIG. 2. 1... Vertical crusher, 3... Rotary table,
4... Grinding roller, 6... Pressure frame, 14...
- Annular space part, 15... Classifier, 16... Raw material supply pipe, 23... Rotating shaft, 27... Vane,
30... End plate.

Claims (1)

[Claims] (1) The top of the casing is equipped with an opening for the air flow of refined powder, and a classifier is installed in the upper part of this casing. In a vertical crusher that is a rotary classifier that is supported by a shaft and includes rotating blades arranged annularly and radially around the rotating shaft, a classifier is attached to an outer edge of the rotating blade. A vertical crusher characterized in that an end plate that intersects diagonally with the radial direction is fixed at an angle such that the front edge side in the rotation direction of the end plate is located closer to the center of the classifier than the rear edge side.