JPH11207202A - Vertical mill rotary classifier - Google Patents

Abstract

(57) [Summary] PROBLEM TO BE SOLVED: To reduce the height of a vertical mill as a whole to achieve downsizing, to reduce the cost and increase the degree of freedom in layout and other aspects, and to classify the rotary mill of a vertical mill. Offer machine. A rotating blade is provided on a rotating shaft so as to radially protrude from the rotating shaft in a radial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary classifier for a vertical mill.

[0002]

2. Description of the Related Art As a mill for pulverizing a granular material such as coal supplied to a coal-fired boiler to obtain a fine powder such as pulverized coal, there is a conventional mill as shown in FIG.
In the figure, reference numeral 1 denotes a vertical mill.

[0003] In the lower part of the casing 2 of the vertical mill 1, a table 5 which is rotationally driven by a driving device 3 such as a motor via a speed reducer 4 is arranged. The pivot bracket 6 is attached to the casing 2
The pivot bracket 6 is provided with a roller 8 that rotates about an axis O extending in a direction substantially perpendicular to the horizontal shaft 7 at the tip of the pivot bracket 6. A fluid pressure cylinder 9 using a fluid such as oil is attached to the journal cover 2 a of the casing 2, and a rod 9 a of the fluid pressure cylinder 9 is extended to fit into the plunger housing 10. By pressing the pressing portion 6a of the pivot bracket 6 via the plunger 11, the roller 8 is pressed against the upper surface of the horizontally rotating table 5, and the roller 8 and the table 5 cooperate, and the coal or the like on the table 5 Can be crushed.

In the casing 2, an annular body 12 is disposed so as to surround the table 5, and the annular body 12 has
An air port 14 is provided so that the primary air 13 introduced into the casing 2 from a position below the table 5 of the casing 2 can be blown into the upper portion of the casing 2.

A head frame 15 is provided outside the upper portion of the casing 2 so as to communicate with the inside of the casing 2, and a bearing tube 16 is fixed in the head frame 15 so as to extend vertically. Bearings 17 and 18 are fitted in the bearing cylinder 16 at a predetermined interval A in the vertical direction, and fine powder such as pulverized coal is burned into a side portion of the head frame 15 by a burner (not shown) of a boiler. A fine powder feed pipe 19 for feeding the powder is connected.

A hollow cylindrical rotary shaft 20 extending vertically is fitted into the bearings 17 and 18, and a rotary classifier 21 is mounted on a portion of the rotary shaft 20 extending into the casing 2.
A pulley 22 is fitted to a portion of the rotary shaft 20 extending above the bearing tube 16.
A pulley 25 is fitted to an output shaft 24 of a driving device 23 such as a vertical motor installed outside the upper portion of the casing 2. The pulley 25 is fitted to the pulley 22 fitted to the rotary shaft 20. An endless belt 26 is looped between them.

In the rotary classifier 21, a rotary plate 27 is fitted to the lower end of the rotary shaft 20, and an outer peripheral portion of the rotary plate 27 is
The rotary classifier 21 has a configuration in which a large number of flat blades 28 extending upward are provided, and the weight of the rotary classifier 21 is supported by a bearing 17 disposed above the bearing cylinder 16. On the other hand, when the rotary classifier 21 rotates, the radial load acting on the rotating classifier 21 is reduced by the bearing 18 located on the lower side of the bushing 16.
Therefore, a bearing such as a conical roller bearing is used as the bearing 17, and a bearing such as a cylindrical roller bearing is used as the bearing 18. In the drawing, reference numeral 29 denotes a support beam radially extended from the rotary shaft 20 to support the rotary wing 28.

A chute pipe 3 having an upper end connected to a chute of a coal feeder (not shown) is provided inside the rotary shaft 20.
0 is arranged to open slightly above the roller 8 in the casing 2.

Further, a truncated inverted conical reject chute 31 is provided in the casing 2 so as to be located below the rotary classifier 21. A slit 32 extending along the inclined surface is formed so that a powder obtained by pulverizing a granular material such as coal blown up by the air 13 can pass therethrough.

[0010] In the vertical mill 1 shown in FIG. 7, granular material such as coal cut out from a coal hopper (not shown) to a coal feeder is fed from a chute of the coal feeder via a chute pipe 30 to a casing 2. Of the table 5, which is driven by the driving device 3 via the speed reducer 4 and is rotating in the horizontal direction, and the roller 8 which is in contact with the table 5 and is rotating. The powder such as coal, which is pulverized by the cooperative operation, rises in the casing 2 as shown by an arrow accompanied by the primary air 13 blown out from the air port 14, passes through the slit 32 of the reject chute 31, The rotary shaft 2 is blown up above the reject chute 31 and driven by the driving device 23.
The coarse powder is classified by the rotary classifier 21 rotating together with 0, and the fine powder such as the pulverized coal obtained by classifying the coarse powder enters the head frame 15 through the rotary classifier 21 and from the head frame 15. The coarse powder that has been sent out to the fine powder feed pipe 19 and sent to the burner (not shown) of the boiler and that has been classified by the rotary classifier 21 slides down the reject chute 31 and returns to the table 5. It is.

[0011]

In the case of the rotary classifier 21 of the conventional vertical mill 1 as described above, the rotary shaft 2
Since the rotary wings 28 are arranged in the vertical direction so as to extend substantially parallel to 0, the height at the rotary wing 28 portion of the rotary classifier 21 increases, and accordingly, the rotary classifier 2
The position G of the center of gravity of the rotating blade 28 of the
Since the distance B from the bearing 18 such as a cylindrical roller bearing for supporting the radial load of the rotary classifier 21 which is located below the rotary classifier 21 becomes longer, the rotary classifier 21 is stably supported. To do this, the lower bearing 18
The distance A between the bearing 17 and a conical roller bearing or the like for supporting the weight of the rotary classifier 21 and the load in the radial direction located above the bearing cylinder 16 must also be increased. However, the height of the entire vertical mill 1 is increased, leading to an increase in cost and a disadvantage in terms of layout and the like.

The present invention has been made in view of the above-mentioned circumstances, and is intended to reduce the height of the entire vertical mill to achieve downsizing, to reduce costs and increase the degree of freedom in layout and the like. Of the present invention is to provide a rotary classifier.

[0013]

SUMMARY OF THE INVENTION According to the present invention, a powder which is crushed and blown up by a roller pressed against the upper surface of a table is repelled by a rotary wing which is driven to rotate about a vertically extending rotary shaft. A rotary classifier of a vertical mill for classifying coarse powder falling into a fine powder and fine powder passing through a rotary blade, wherein a rotary blade is disposed on a rotary shaft so as to radially project from the rotary shaft in a radial direction. The present invention relates to a rotary mill of a vertical mill.

Further, according to the present invention, the powder crushed and blown up by a roller pressed against the upper surface of the table is provided.
A rotary mill of a vertical mill that classifies coarse powder falling on a table by being repelled by a rotary wing that is driven to rotate around a rotating shaft extending in the vertical direction, and fine powder passing through the rotary wing. On the outer peripheral side of the shaft, an intermediate annular body having a larger diameter than the rotating shaft and an annular body having a larger diameter than the intermediate annular body are disposed concentrically with the rotating shaft, and are disposed between the rotating shaft and the intermediate annular body. Rotating blades are provided so as to radially project from the rotating shaft in the radial direction, and between the intermediate annular members, the rotating blades are radially projecting radially from the intermediate annular member. The present invention relates to a rotary mill of a vertical mill, which is characterized in that it is installed.

According to the above means, the following effects can be obtained.

The powder crushed and blown up by the cooperative operation of the table and the rollers is classified into coarse powder by a rotating rotary classifier, and the fine powder obtained by classifying the coarse powder is rotated by a rotary classifier. Is passed through to the boiler burner, etc.
The coarse powder classified by the rotary classifier is returned to the table, but in the case of the rotary classifier of the vertical mill of the present invention, the rotating blades extend radially with respect to the rotating shaft extending in the vertical direction. Since it is arranged to project radially, the height of the rotary wing portion of the rotary classifier does not increase, and the center of gravity position of the rotary wing portion of the rotary classifier and the lower position of the bearing cylinder The distance between the rotary classifier and a bearing composed of a cylindrical roller bearing or the like for supporting a radial load is reduced, and the rotary classifier is positioned above the bearing cylinder and above the bearing cylinder. Without increasing the distance between bearings such as conical roller bearings to support the dead weight and radial load of the bearing,
It is possible to stably support the rotary classifier.

As a result, the height of the entire vertical mill is reduced, which leads to downsizing and cost reduction, and is advantageous in terms of layout and the like.

[0018]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show an embodiment of the present invention. In the drawings, the portions denoted by the same reference numerals as those in FIG. 7 represent the same components, and the basic configuration is shown in FIG. The present embodiment is the same as the conventional one shown in FIG. 1, but the feature of the illustrated example is that, as shown in FIGS. It is in the point that was arranged.

In the illustrated example, as shown in FIG. 1, an annular body 33 having an outer diameter slightly smaller than the inner diameter of the casing 2 is provided concentrically with the rotating shaft 20 as shown in FIG. The rotating shaft 20 and the annular body 33 are connected by a rotating blade 28, and the rotating blade 28 has a required inclination angle with respect to the horizontal direction based on the rotating direction of the rotating shaft 20, as shown in FIG. It is arranged with α.

In the illustrated example, the reject chute 31 as shown in FIG. 7 is not installed, but it goes without saying that it may be installed as needed.

Next, the operation of the illustrated example will be described.

Granules such as coal cut out from a coal hopper (not shown) to a coal feeder are put into a casing 2 from a chute of the coal feeder via a chute tube 30 and fall onto a table 5. The table 5 is driven by the drive unit 3 through the speed reducer 4 and is rotated in the horizontal direction. The table 5 is rotated by the cooperation of the roller 8 which is in contact with the table 5 and is rotated. The powder of the powder and the like is entrained by the primary air 13 blown out from the air port 14 and rises in the casing 2 as shown by the arrow, and is coarsely moved by the rotary classifier 21 driven by the driving device 23 and rotating together with the rotary shaft 20. The fine powder such as pulverized coal obtained by classifying the powder and classifying the coarse powder passes through a rotary classifier 21 and is fed from a fine powder feed pipe 19 to a burner (not shown) of a boiler.
The coarse powder classified by the rotary classifier 21 is placed on a table 5
Returned to the top.

The rotary classifier 21 of the vertical mill 1 in the illustrated example.
In this case, the rotating blades 28 are
Are arranged so as to radially project in the radial direction, the height of the rotary classifier 21 at the rotor 28 is not increased, and the center of gravity G ′ of the rotary classifier 21 at the rotor 28 is not increased. The distance B ′ between the bearing 18 and a cylindrical roller bearing for supporting the radial load of the rotary classifier 21 located on the lower side of the bearing cylinder 16 is shortened. Without increasing the distance A 'between the bearing 18 and the bearing 17 such as a conical roller bearing for supporting the weight of the rotary classifier 21 and the load in the radial direction, which is located above the bearing cylinder 16. Thus, the rotary classifier 21 can be stably supported.

As a result, the height of the entire vertical mill 1 is reduced, which leads to downsizing and cost reduction, and is advantageous in terms of layout and the like.

As described above, the height of the entire vertical mill 1 can be reduced to reduce the size, and the cost can be reduced and the degree of freedom in layout and the like can be increased.

FIGS. 4 to 6 show another embodiment of the present invention. In the drawings, the portions denoted by the same reference numerals as those in FIGS. 1 to 3 represent the same components. An intermediate annular body 34 is disposed between the rotating body 20 and the annular body 33, and the rotating shaft 20 and the intermediate annular body 34 are connected to each other by a rotary wing 28a, and the intermediate annular body 34 and the annular body 33 are rotated. Wing 2
8b.

The rotating blades 28a and 28b are
As shown in FIG. 6, based on the rotation direction of the above, the tilt angle .alpha. With respect to the horizontal direction is provided.

In the case of the rotary classifier 21 shown in FIGS. 4 to 6, the rotary blades 28a,
Since the protrusions 28b are radially extended in the radial direction, the height of the rotary classifier 21 at the rotating blades 28a and 28b does not increase, and the height of the rotating classifier 21 at the rotating blades 28a and 28b is small. Center of gravity position G '(see FIG. 5)
And a distance B ′ (see FIG. 1) between the bearing 18 and a cylindrical roller bearing or the like located below the bearing cylinder 16 and supporting a radial load of the rotary classifier 21 is reduced. A space A ′ between a lower bearing 18 of the bearing cylinder 16 and a bearing 17 formed of a conical roller bearing or the like located above the bearing cylinder 16 and supporting the weight of the rotary classifier 21 and the load in the radial direction. (See FIG. 1) without increasing the length of the rotary classifier 21.
Can be stably supported. As a result, the height of the entire vertical mill 1 is reduced, which leads to downsizing and cost reduction, and is advantageous in terms of layout and the like.

Thus, in the case of the example shown in FIGS. 4 to 6, as in the case of the example shown in FIGS. 1 to 3, the height of the entire vertical mill 1 can be reduced and the size can be reduced. , Cost, and the degree of freedom in layout and the like can be increased.

The rotary classifier of the vertical mill according to the present invention comprises:
It is needless to say that the present invention is not limited to the illustrated example described above, and various changes can be made without departing from the scope of the present invention.

[0032]

As described above, according to the rotary classifier of the vertical mill of the present invention, the height of the entire vertical mill can be reduced to reduce the size, and the cost and layout can be reduced. In this case, it is possible to obtain an excellent effect that the degree of freedom in the aspect can be increased.

[Brief description of the drawings]

FIG. 1 is an overall schematic side sectional view of an example of an embodiment of the present invention.

FIG. 2 is a plan view of an example of an embodiment of the present invention, and is a view corresponding to the direction of arrows II-II in FIG.

FIG. 3 is a view taken in the direction of arrows III-III in FIG. 2;

FIG. 4 is a plan view of another example of an embodiment of the present invention.

FIG. 5 is a sectional view taken along line VV of FIG. 4;

FIG. 6 is a view taken in the direction of arrows VI-VI in FIG. 4;

FIG. 7 is an overall schematic side sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vertical mill 5 Table 8 Roller 16 Bearing cylinder 17 Bearing 18 Bearing 20 Rotating shaft 21 Rotary classifier 28 Rotating blade 28a Rotating blade 28b Rotating blade A 'interval B' distance G 'center of gravity

Claims (2)

[Claims] 1. A powder which is pulverized and blown up by a roller pressed against an upper surface of a table is repelled by a rotating wing which is driven to rotate about a rotating shaft extending in a vertical direction, and a coarse powder which falls on the table, A rotary mill of a vertical mill that classifies fine powder passing through the wings,
A rotary mill classifier for a vertical mill, wherein a rotary blade is provided on a rotary shaft so as to radially project from the rotary shaft in a radial direction. 2. A coarse powder which is pulverized by a roller pressed against a table upper surface and blown up by a rotating wing which is driven to rotate about a rotating shaft extending in a vertical direction and falls onto the table by being repelled. A rotary mill of a vertical mill that classifies fine powder passing through the wings,
On the outer peripheral side of the rotating shaft, an intermediate annular body having a larger diameter than the rotating shaft,
An annular body having a diameter larger than that of the intermediate annular body is disposed concentrically with the rotating shaft, and a rotor is disposed between the rotating shaft and the intermediate annular body so as to radially project from the rotating shaft in a radial direction. A rotary classifier for a vertical mill, wherein a rotating blade is disposed between the intermediate annular member and the annular member so as to radially project from the intermediate annular member in a radial direction.