JPH0225480Y2 - - Google Patents

Description

[Detailed Description of the Invention] "Field of Application of the Invention" The present invention relates to a seal structure in a mill chamber of a vertical crusher, and particularly to a seal structure that can perform sufficient sealing using air pressure.

"Prior Art" First, an example of a vertical crusher will be briefly described using FIG. 2.

FIG. 2 is a schematic front cross-sectional view of a vertical roller mill, in which a casing 1 formed roughly in a cylindrical shape forms a mill chamber 2, and a crushing table 3 rotatably driven by a motor not shown in the mill chamber 2. is located. A plurality of crushing rollers 5 are provided on the crushing table 3 and are urged by a pressing device 4 constituted by a spring, a hydraulic device, or the like. The grinding rollers 5 are each rotatably attached to a roller shaft 8 fixed to an arm 7 swingably attached to a horizontal shaft 6, and rotate as the grinding table 3 rotates. Further, a classifier 10 having blades 9 around the periphery is provided in the upper part of the mill chamber, and the rotation of the classifier 10 causes the air around the classifier 10 to swirl.

Furthermore, a nozzle 11 that is inclined in one direction is provided around the entire circumference of the grinding table 3, and a suction device such as a blower is connected to a discharge port 12 provided at the top of the mill chamber 2. The air inside the mill chamber 2 is sucked from the outlet, and the air sucked into the mill chamber 2 through the inclined nozzle 11 swirls and flows through the mill chamber 2.
After rising inside, it is discharged from the discharge port 12.

Therefore, the raw material inputted from the raw material supply port 13 provided on the side of the casing 1 is supplied to the center of the crushing table 3, and the upper surface of the crushing table 3 is passed through the nozzle by the centrifugal force accompanying the rotation of the crushing table 3. 11
The air flow starts to flow in the direction of , is caught in the gap between the crushing table 3 and the crushing roller 5, and is crushed under pressure, and then further moves toward the outer circumference of the crushing table 3 and is blown up from the nozzle 11. exposed to Raw materials with large particle diameters cannot ride the upward swirling flow and return to the grinding table 3 where they are further ground. The raw material having a certain small particle size rises on the swirling airflow, and is caught in the swirling airflow accompanying the rotation of the classifier 10 in the vicinity of the classifier 10.
Under the centrifugal force caused by this swirling airflow, the raw material with a relatively large particle size comes into contact with the inner surface of the casing 1, slows down, falls along the inner surface of the casing 1, and returns to the top surface of the grinding table 3. do.

In addition, the sufficiently pulverized raw material having a small particle size is discharged to the outside from the discharge port 12 along with an upward air current despite the centrifugal force exerted by the classifier 10.

The structure of such a vertical crusher is already known, for example, as described in Japanese Utility Model Application Publication No. 141739/1983.

``Problems with the prior art'' As mentioned above, the vertical crusher is usually a negative pressure type mill where the inside of the mill chamber 2 is under negative pressure, and the pressure difference between it and the outside air is, for example, about 100 to 200 mmAq. Therefore, even if the sealing of the sliding part (indicated by arrow A) between the grinding table 3 and the mill casing 1 is somewhat incomplete, air leakage into the mill chamber 2 will cause problems in the grinding and drying of the grinder. Therefore, a simple seal structure such as a labyrinth seal is used for the seal portion A.

However, when crushing explosive raw materials such as pulverized coal with a vertical crusher, generally the mill chamber 2 is filled with inert gas under pressure, and the mill chamber 2 is filled with inert gas under pressure. However, when sealing part A is prevented from leaking with a simple structure such as a labyrinth seal as described above, the pulverized raw material may be exposed to hot air gas. There is a danger that the leakage will take advantage of the leak and cause it to spray out from the seal. In addition, even in a negative pressure type where the inside of the mill chamber 2 is not pressurized, when processing explosive raw materials, an inert gas such as carbon dioxide gas is forced to flow in, so it is necessary to keep the oxygen concentration in the mill chamber 2 low. However, even in this case, if the seal is incomplete, the inflow of standby gas will cause damage to the mill chamber 2.
There are other cases where there is a risk of an internal odor explosion.

OBJECT OF THE INVENTION Accordingly, the present invention provides a structure for strengthening the seal of the joint formed between the grinding table casing of a vertical grinder and the grinding table casing of a vertical grinder.

"Structure of the invention" The main means adopted by the invention to achieve the above purpose is to
In a vertical crusher that rotates a crushing table around a vertical axis and crushes raw materials between a crushing roller that is pressed in the direction of the top surface of the crushing table and the top surface of the crushing table, the casing and the crushing table are combined. An annular gas chamber is formed at the joint portion of the gas chamber, an annular rubber seal having a substantially V-shaped cross section is interposed in the sealing portion of the gas chamber, compressed gas is sealed in the gas chamber, and the annular rubber seal is attached to the gas chamber wall surface or pulverized. The seal structure of the vertical crusher is such that it is pressed against the wall of the table and sealed, and the annular rubber seal is pressed against the wall of the gas chamber or the wall of the crushing table by the pressure of the compressed gas sealed in the annular gas chamber. This prevents outside air from flowing into or out of the mill chamber.

The cross-sectional shape of the annular rubber seal in the above component is V-shaped, but this does not necessarily mean that the entire annular rubber seal is integrally molded, but may be split in the middle or formed in a V-shape. It suffices to have a roughly V-shape configuration, such as one in which the

``Example'' Next, an example in which the seal structure according to the present invention is applied to the sealing part A between the casing 1 and the crushing table 3 in FIG. 2 will be explained with reference to FIG. Serve.

Note that the same reference numerals are used for the same elements as those of the conventional device shown in FIG. 2 for explanation.

In FIG. 1, the bottom plate 1a of the casing 1 has an insertion hole 15 formed in its center for inserting the center body 3a of the crushing table 3, and an annular mounting plate 16 is fixed to the insertion hole 15. There is. Further, on the lower surface of the mounting plate 16, a substantially mortar-shaped gas chamber side wall 17 is provided.
is fixed to the lower surface of the mounting plate 16 and the lower surface of the gas chamber side wall 17, respectively.
8 and 19 are fixed. The horizontal plates 18 and 19 are respectively connected to the body 3 of the grinding table 3.
The outer peripheral surface 3b of the body 3a, the horizontal plate 18, the mounting plate 16, the gas chamber side wall 1
7 and the horizontal plate 19 constitute an annular gas chamber 20 surrounding the body 3a of the crushing table 3.

Further, an annular rubber seal 21 having a substantially V-shaped cross section is fixed to the outer peripheral surface 3b of the body 3a, and the tips of the lip portions 21a and 21b of this rubber seal 21 are attached to the lower surface of the horizontal plate 18 and the upper surface of the horizontal plate 19, respectively. At least one gas introduction part 22 is attached to the side wall of the gas chamber in sliding contact with each other, and this gas introduction part 22 is connected to a high-pressure gas source (not shown).

Therefore, through the gas introduction section 22, the gas chamber 20
When high-pressure air or inert gas is introduced into the mill chamber 20, the internal pressure of the gas chamber 20 increases, and the lips 21a and 21b are pressed against the horizontal plates 18 and 19, causing a gap between the gas chamber 20 and the mill chamber 2. Each of the gaps 18a and 19a is accurately sealed,
These two seal structures completely shut off the outside air and the inside of the mill chamber, thereby preventing inconveniences such as compressed gas in the mill chamber 2 leaking out of the mill or air leaking into the mill chamber 2.

The above embodiment is only a specific example of the present invention,
The present invention can be modified in various ways within the scope of the technical matters stated in the claims for utility model registration. For example, in the above embodiment, an annular rubber seal is attached to the grinding table side, but such a rubber seal can also be attached to the casing side. The same effect as in the above embodiment can be obtained even if the pressure is applied by pressing, and this also corresponds to an embodiment of the present invention.

``Effect of the invention'' As described above, the present invention consists of rotating a grinding table around a vertical axis in a mill chamber surrounded by a casing, and using a grinding roller and a grinding roller that are pressed in the direction of the top surface of the grinding table. In a vertical crusher that crushes raw materials with the top surface of the table, an annular gas chamber is formed at the joint between the casing and the crushing table, and an annular rubber seal with a roughly V-shaped cross section is installed in the sealing area of this gas chamber. The sealing structure of the vertical crusher is characterized in that the gas chamber is filled with compressed gas and the annular rubber seal is pressed against the gas chamber wall surface or the crushing table wall surface for sealing. The pressure of the compressed gas introduced presses the rubber seal against the side of the gas chamber or the wall of the grinding table, creating a strong leak-proof structure with rubber seals in two locations: between the outside air and the gas chamber, and between the gas chamber and the mill chamber.
The airtight structure inside and outside the mill chamber has been completely completed, and we have succeeded in providing a vertical crusher that is safe on the sealing surface.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing a seal structure portion of a vertical crusher having a seal structure according to an embodiment of the present invention, and FIG. 2 is a schematic front sectional view showing an example of a conventional vertical crusher. Explanation of symbols, 1... Casing, 2... Mill chamber, 3... Grinding table, 5... Grinding roller, 1
a... Casing bottom plate, 3... Body of crushing table, 16... Mounting plate, 17... Gas chamber side wall, 1
8, 19...horizontal plate, 20...gas chamber, 21...
Rubber seal, 22...Gas introduction part.

Claims (1)

[Scope of utility model registration request] Vertical pulverization involves rotating a pulverizing table around a vertical axis in a mill chamber surrounded by a casing, and pulverizing the raw material between the pulverizing rollers that are pressed toward the top of the pulverizing table and the top of the pulverizing table. In the machine, an annular gas chamber is formed at the joint between the casing and the grinding table, an annular rubber seal having a substantially V-shaped cross section is interposed in the sealing portion of the gas chamber, and compressed gas is sealed in the gas chamber. A sealing structure for a vertical crusher, characterized in that the annular rubber seal is pressed against a gas chamber wall surface or a crushing table wall surface for sealing.