RU2388679C1 - Unit of rotation - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: unit of rotation consists of case (1) mounted on axle (4) in bearing units (2) forming cavity (5) between internal surface of the case and external surface of the axle and of casing (8) deformed under effect of pressure difference, located in the said cavity and communicated with atmosphere. The casing is communicated with atmosphere by means of a chamber made in the axle. The unit can be equipped with protecting perforated jacket (9) wherein there is installed the said casing.

EFFECT: eliminating cause of dust penetration into structure of unit, decreasing wear of parts and increasing service life of unit.

3 cl, 2 dwg

Description

The claimed invention relates to a rotation unit, which will find application, for example, in belt conveyors operated in a dusty atmosphere of coal, mining or construction.

Known rollers of conveyor belts, including a sealed cylindrical housing mounted rotatably around a hollow shaft in bearing assemblies provided with external seals. The outer seals of the bearing units provide protection for the latter from abrasion by particles of coal, rocks, components of building materials present in the atmosphere of an industrial production.

To protect the bearing assemblies, the sealing elements are made in the form of a pack of rings of elastically deformable, different in density porous material containing a lubricating fluid (RU 2278069 C1, publ. 06/20/2006).

To protect the bearing assemblies, the cavities between the roller conveyor housing and the friction unit are filled with a composite consisting of chips of antifriction self-lubricating material, grease and solid lubricant (RU 2238901, publ. 10.27.2003).

These technical solutions do not provide reliable protection of the bearing assemblies from the abrasive effects of solid particles present in the atmosphere of operation of these devices.

Closest to the proposed technical solution is the rotation unit, which is a roller conveyor belt described in RU 2260553 C2, publ. 09/10/2004. The specified device contains a sealed cylindrical housing mounted in the bearing units with the possibility of rotation around the hollow shaft and containing an annular cavity formed by the inner walls of the housing and the outer wall of the hollow shaft. Bearing units have external seals, while between these seals and bearings chambers are formed containing porous material impregnated with oil. Protection against the penetration of abrasive dust of the atmosphere into the bearings of the conveyor rollers is carried out as follows. In the case of the formation of a pressure differential between the atmosphere of the external environment and the internal cavities of the roller, dusty air overcomes the external seals and enters the above chambers, where the dust is held by porous material impregnated with oil.

The specified technical solution also does not provide reliable protection of the bearing against abrasion by the abrasive dust of the surrounding atmosphere, since it does not exclude the pressure drop in the bearing assembly, which provokes the movement of abrasive particles and their ingress into the bearing in any protection variant.

All of the above patents partially solve the problem of increasing the service life of the device by removing dust from the air entering the inner cavity of the roller due to pressure differences.

The objective of the invention is to increase the service life of the device by eliminating the reasons that reduce the service life - by preventing the ingress of air with dust into the internal cavity of the device.

The problem is solved in that the rotation unit containing the housing mounted on an axis in the bearing units to form a cavity between the inner surface of the housing and the outer surface of the axis is provided with a shell deformed by the pressure difference located in the specified cavity and in communication with the atmosphere.

Preferably, said shell is in communication with the atmosphere through a channel formed in the axis.

The assembly may be provided with a protective perforated casing in which said casing is located.

Due to the ability of the shell to change its volume, and therefore the free volume of the internal cavity of the housing, the pressure of the internal cavity of the housing in the proposed device will always be equal to atmospheric regardless of the temperature change. If the pressures are equal inside and outside the housing, dusty air will not enter the internal cavity of the device housing, and therefore will not bring abrasive dust into the bearing assembly, which will increase the life of the device.

The invention is illustrated by drawings.

Figure 1 shows a longitudinal section of the proposed device, figure 2 is a cross section of a hollow shaft.

Below is described one of the possible examples of a specific implementation of the proposed rotation node. The rotation unit includes a cylindrical housing 1, mounted by means of bearing units 2 with labyrinth seals 3 on the axis 4 with the formation of an annular inner cavity 5. Inside the axis 4, a tube is located along it with the outlet to the atmosphere. The pipe 7 is made L-shaped and one of its ends is hermetically connected to the tube 6, and its second end is hermetically closed by a shell 8 having an internal cavity and made in the form of a rubber diaphragm. Part of the pipe 7 with the shell 8 is closed with a protective perforated casing 9, mounted on the outer surface of the axis 4.

When using the rotation unit as a roller conveyor belt, it works as follows.

When the conveyor or roller table is turned on by the operator, the cylindrical body 1 rotates around axis 4. During rotation, the temperature in the inner cavity 5 rises, which should lead to an increase in pressure in the cavity 5, provided that the free volume of the specified cavity is kept constant. However, this does not happen, because with increasing pressure, the shell 8 begins to narrow, displacing air from its inner cavity through the pipe 7 to the tube 6 into the atmosphere and thereby increasing the free volume of the inner cavity 5 of the housing 1. As a result, the pressure in the inner cavity 5 will be equal to atmospheric.

When the conveyor or roller table is turned off by the operator, the rotation of the housing 1 is stopped, and the temperature in the internal cavity 5 decreases, which should lead to a decrease in pressure in the cavity 5, provided that the free volume of the specified cavity is kept constant. However, this does not happen, because with decreasing pressure, the shell 8 begins to expand due to the flow of air from the atmosphere into its internal cavity through the tube 6 and pipe 7, and thereby reducing the free volume of the internal cavity 5 of the housing 1. As a result, the pressure in the internal cavity 5 will be equal to atmospheric, and dusty air will not penetrate into the internal cavity 5 of the device body.

Thus, the pressure in the internal cavity 5 of the device will always tend to atmospheric level.

The design of the claimed device eliminates the cause of dust in its internal cavity, which reduces the wear of its parts, increasing the service life of the device.

Claims (3)

1. A rotation assembly comprising a housing mounted on an axis in the bearing units to form a cavity between the inner surface of the housing and the outer surface of the axis, characterized in that it is provided with a shell deformed by a pressure difference located in the cavity and in communication with the atmosphere. 2. The node according to claim 1, characterized in that the shell is in communication with the atmosphere through a channel made in the axis. 3. The node according to claim 1, characterized in that it is equipped with a protective perforated casing in which the specified shell is located.

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