JPH078820A - Seal structure for roller shaft part of vertical mill - Google Patents

Abstract

PURPOSE:To prevent powder in a casing from entering the air chamber so as to eliminate the heaped powder and also to allow the vibration of a roller shaft part by introducing seal air into the air chamber before jetting it into the casing from a nozzle part. CONSTITUTION:A material to be pulverized 3 fed onto a pulverizing table 2 in a casing 1 is pulverized by a roller tire 4. And the pulverized powder 5 is laden on gas 7 from an air port and carried onto the casing 1. In this case, seal air 22 from an air fan 21 is introduced into an air chamber 19, and also it is jetted into the casing 1 from a nozzle part 17. In this way, the powder 5 in the casing 1 is prevented from entering the air chamber 19 from between a seal plate 16 and an elastic nozzle ring 18. On the other hand, the vertical vibration of a roller shaft part 9 is allowed by the sliding of the seal plate 16 on the elastic nozzle ring 18 and the deflection deformation of a flexible membrane 20 forming the air chamber 19.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roller shaft seal structure for a vertical mill.

[0002]

2. Description of the Related Art FIGS. 3 and 4 show an example of a vertical mill, in which a crushing material 3 supplied on a crushing table 2 rotatably driven in an inner lower portion of a casing 1 is used. And a roller tire 4 that is pressed against the crushing table 2 and rotates following the crushing table 2, and the powder 5 obtained by the crushing is an air port opened in an annular shape around the crushing table 2. The gas 7 from 6 is carried over the casing 1 and the powder 5 carried over the casing 1 is classified through a separator 8 and then carried out from the top of the casing 1.

In this type of vertical mill, there is a type in which the roller shaft portion 9 of the roller tire 4 penetrates through the casing 1 as shown in the example of the drawing, but there is a through hole 10 formed in the casing 1. A relatively large gap is formed between the roller shaft portion 9 and the roller shaft portion 9 so as to allow vertical vibration of the roller shaft portion 9 when the roller tire 4 crushes the crushed material 3 on the crushing table 2. Therefore, in order to prevent the powder 5 from leaking out of the casing 1 through the gap, the gap is covered with a bell mouth type rubber seal 11 (or a bellows type rubber seal (not shown)) to seal the gap.

[0004]

However, in the conventional seal structure as described above, the powder 5 is easily deposited on the lower portion of the rubber seal 11. Therefore, the weight of the deposited powder 5 causes the powder 5 to be indicated by a two-dot chain line in FIG. As shown, the lower portion of the rubber seal 11 hangs down, and vertical vibrations act in this state, causing the rubber seal 11 to be damaged in a short period of time.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a roller shaft seal structure for a vertical mill having a longer life than conventional ones.

[0006]

SUMMARY OF THE INVENTION According to the present invention, a roller shaft portion supported by a bearing arranged outside a casing and penetratingly arranged through a through hole opened to the casing, and a roller shaft portion are provided between the through hole. A roller shaft part sealing structure of a vertical mill that seals the powder in the casing so as not to leak outside, the roller shaft part sealing structure being fixed to a required position of a bearing housing that holds the bearing, and the through hole being provided outside the casing. A sealing plate covering the outer peripheral edge of the through hole, an elastic nozzle ring having an outer peripheral edge fixed around the through hole and an inner peripheral edge pressed against the seal plate like a leaf spring to form a nozzle portion, and an outer peripheral edge of the seal plate elastically. And a flexible coating which is provided between the casing wall around the nozzle ring and an outer circumference of the nozzle to form an air chamber into which seal air can be introduced.

[0007]

Therefore, according to the present invention, when the seal air is introduced into the air chamber, the seal air is ejected from the nozzle portion into the casing, so that the powder inside the casing is introduced from between the seal plate and the elastic nozzle ring into the air chamber. It is possible to prevent the powder from leaking into the inside of the casing and prevent the powder from leaking to the outside of the casing.

On the other hand, the vertical vibration of the roller shaft portion generated when the roller tire crushes the crushed material on the crushing table causes the sealing performance due to the sliding of the seal plate with respect to the elastic nozzle ring and the bending deformation of the flexible coating. Allowed while holding.

[0009]

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

FIGS. 1 and 2 show an embodiment of the present invention, in which parts designated by the same reference numerals as those in FIGS. 3 and 4 represent the same parts.

In the figure, 12 is a vertical mill having substantially the same structure as the vertical mills shown in FIGS. 3 and 4, 13 is a bearing for supporting the roller shaft portion 9 outside the casing 1, and 14 is the bearing 13. A bearing housing 15 to be held is a bearing cover that constitutes an end surface of the bearing housing 14 on the roller tire 4 side, and a through hole 10 is covered from the outside of the casing 1 at a position close to the casing 1 of the bearing cover 15. A ring-shaped seal plate 16 is fixedly provided so that the inner peripheral edge of the casing 1 can be pressed against the seal plate 16 like a leaf spring to form a nozzle portion 17 around the through hole 10. The outer peripheral edge of the elastic nozzle ring 18 is fixed.

Further, between the outer peripheral edge of the seal plate 16 and the wall of the casing 1 around the elastic nozzle ring 18, a flexible coating 20 is formed so that an air chamber 19 is formed on the outer periphery of the nozzle portion 17. The flexible coating 20 is provided with a flexible shape that bulges toward the bearing housing 14 so as to allow the vibration of the roller shaft portion 9.

An air fan 21 is disposed at a required location outside the casing 1, and sealing air 22 from the air fan 21 is introduced through an air supply hole 23 provided at a required position of the flexible coating 20. It can be introduced into the air chamber 19.

In this embodiment, the air chamber 2 is also provided in the portion of the bearing cover 15 closest to the roller tire 4 side.
4 is formed so that a part of the seal air 22 from the air fan 21 can be branched and introduced into the air chamber 24.

When the seal air 22 is introduced into the air chamber 19 by the air fan 21, the seal air 22 is ejected from the nozzle portion 17 into the casing 1, so that the powder 5 inside the casing 1 is sealed by the seal plate. 16 and the elastic nozzle ring 18 are prevented from entering the air chamber 19, and the powder 5 is prevented from leaking to the outside of the casing 1.

On the other hand, the vertical vibration of the roller shaft portion 9 generated when the roller tire 4 crushes the crushed material 3 on the crushing table 2 causes the sliding of the seal plate 16 with respect to the elastic nozzle ring 18 and the flexible coating 20. Due to the flexural deformation, the sealing property is maintained.

In this embodiment, a part of the seal air 22 from the air fan 21 can be branched and introduced into the air chamber 24 formed in the bearing cover 15, so that the bearing can be introduced from the inside of the casing 1. Invasion of the powder 5 into the housing 14 is also prevented.

Therefore, according to the above embodiment, the roller shaft portion 9
The powder 5 in the casing 1 can be securely sealed so as not to leak to the outside while allowing the vibration of the powder 1. There is no risk of damage due to the accumulation of the, and the life of the seal structure can be remarkably extended.

Further, since the seal structure of the roller shaft portion 9 can be compactly and collectively arranged at a position close to the through hole 10, the space occupied by the seal structure can be greatly reduced as compared with the conventional case.

The roller shaft seal structure of the vertical mill of the present invention is not limited to the above-mentioned embodiment,
Needless to say, various changes can be made without departing from the scope of the present invention.

[0021]

According to the above-described roller shaft portion sealing structure of the vertical mill of the present invention, the powder in the casing can be reliably sealed while allowing the vibration of the roller shaft portion to leak out. Moreover, since the structure does not cause powder accumulation, there is no risk of damage due to powder accumulation as in the conventional structure, the life of the seal structure can be remarkably extended, and a position closer to the through hole can be achieved. Since they can be compactly and collectively arranged, the space occupied by the seal structure can be greatly reduced as compared with the conventional case, and various excellent effects can be obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a view taken along the line II-II in FIG.

FIG. 3 is a cross-sectional view showing a conventional example.

FIG. 4 is an enlarged cross-sectional view around the roller shaft portion of FIG.

[Explanation of symbols]

 1 Casing 5 Powder 9 Roller Shaft Part 10 Through Hole 12 Vertical Mill 13 Bearing 14 Bearing Housing 16 Seal Plate 17 Nozzle Part 18 Elastic Nozzle Ring 19 Air Chamber 20 Flexible Coating 22 Seal Air

Claims (1)

[Claims] 1. The powder in the casing is provided between a roller shaft portion axially supported by a bearing arranged outside the casing and penetratingly arranged through a through hole opened in the casing and the through hole. A vertical shaft roller shaft sealing structure for sealing so as not to leak outside, a seal plate fixed to a required position of a bearing housing holding the bearing to cover the through hole from the outside of the casing, An elastic nozzle ring whose outer peripheral edge is fixed around the through hole and whose inner peripheral edge is pressed against the seal plate like a leaf spring to form a nozzle portion; and an outer peripheral edge of the seal plate and a casing wall portion around the elastic nozzle ring. And a flexible coating which forms an air chamber into which the seal air can be introduced around the nozzle portion, and a sealing structure for the roller shaft portion of the vertical mill.