JPS6041537A - Apparatus for removing automatically deposited product - Google Patents

Abstract

PURPOSE:To strip off and remove easily excessive product of reaction deposited to inside wall of discharge passage by providing a coil shaped resilient body to the inside wall of a discharge passage for discharging excessive product of the reaction from a reaction vessel and twisting the resilent body and returning quickly to the original state. CONSTITUTION:A seed bar 3 is suspended in a reaction vessel 1 and gaseous raw material for glass is ejected from an oxyhydrogen burner 2 at the bottom of the reaction vessel 1 to cause deposition of base material 4 for optical fiber by flame hydrolytic reaction to the top of the seed bar 3. In this case, excessive reaction product is cooled quickly when it is discharged through a discharge passage 5 of the vessel 1 and deposits and accumulates on the inside wall of the discharge passage 5 to make the passage 5 narrow and cause clogging of the passage finally. A coil shaped resilient body 13 is fitted to the inside wall of the discharge pipe 11 of the excessive product and an end of the resilient body is fixed to a rotatable ring 14 and the other end is fixed to a friction ring 12. By the revolution of a roller 16 by the driving of a motor 15, the rotatable ring 14 contacting with the roller is revolved and the resilient body 13 is twisted, but the resilient body restores its original shape quickly by the rotation of the friction ring 12. Deposited product is stripped off by the vibration in this stage, and recovered easily.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic deposit removal device δ that prevents deposits from being deposited in an exhaust passage.

When supplying the raw materials and reaction medium necessary for the reaction into the reaction vessel to obtain the desired reactant, a reaction surplus is generated.
Generally, a discharge passage is provided for exhausting the reaction surplus by pressure, suction, or natural flow. As such a reaction vessel, a reaction apparatus for producing an optical fiber preform by the VAD method is shown in FIG. As shown in the figure, a seed rod 3 is suspended vertically within the reaction vessel i, and an oxyhydrogen flame burner 2 is installed on the bottom face of the seed rod 3, facing the seed rod 3. Glass raw materials, etc. are ejected from this oxyhydrogen flame burner 2 to cause a flame hydrolysis reaction, and the generated glass particles are deposited on the seed rod 3. At the same time, the seed rod 3 is pulled up to produce a porous base material of 4 gold. ing. At this time, glass raw material.

All of the glass particles participate in the reaction and do not necessarily adhere to and accumulate on the seed rod 3, and a discharge path 5 is connected to the reaction vessel 1 to discharge the remainder as a reaction surplus. This discharge path 5 is connected to a surplus treatment device (not shown), and most of the reaction surplus is sucked into the surplus treatment device through this discharge path 5. However, since the reaction surplus immediately after the flame hydrolysis reaction is fine and solidified at a high temperature, it is cooled while passing through the inside of the discharge passage 5, gradually adheres and accumulates on the inner wall of the discharge passage 5, and finally ends up in the discharge passage 5. It may even lead to blockage. What is particularly important in the method for producing an optical fiber base material by the VAD method is that the distribution of glass particles in the space between the oxyhydrogen flame burner 2 and the seed rod 3 is formed so that a predetermined refractive index distribution is obtained. , the distribution of the glass particles is maintained without fluctuation for a predetermined period of time. However, as described above, the reaction surplus adheres and accumulates in the discharge passage 5 as deposits 6, and the diameter of the discharge passage 5 becomes narrow.
If the V
This makes continuous production, which is a feature of the AD method, impossible.

In this way, in the conventional VAD-based optical fiber base material reaction device, reaction surplus adheres and accumulates in the discharge path 5.
It was not possible to maintain the reaction conditions in the reaction vessel constant, and it was not possible to continuously produce an optical fiber preform having a predetermined refractive index distribution.

In view of the above circumstances, it is an object of the present invention to completely prevent reaction surpluses from adhering and accumulating in the discharge channel, and to maintain constant reaction conditions within the reaction vessel. The structure of the present invention that achieves such an object is that an elastic body is installed along the inner wall of the discharge passage for exhausting the reaction surplus from the reaction vessel, and after the elastic body is twisted, it suddenly returns to its original state. The present invention is characterized in that a vibration mechanism is provided to restore the state to the above state, and the deposits of the reaction surplus are peeled off from the elastic body.

EMBODIMENT OF THE INVENTION Hereinafter, the automatic deposit removal device of the present invention will be described in detail based on examples.

FIG. 2 shows an embodiment of the present invention. As shown in the figure,
Exhaust pipe 1 connected to the reaction vessel (not shown) as a discharge path
A coil-shaped elastic body 13 is attached along the inner wall of 1. Further, a vibration mechanism is provided for restoring the coiled elastic body 13 to its twisted state. That is, a friction ring 12 that comes into frictional contact with one end of the elastic body 13 is fitted on the inner periphery of one end of the exhaust pipe 11, and one end of the elastic body 13 contacts the friction ring 12 when the torque is less than the frictional resistance. It will be fixed. On the other hand, a rotary ring 14 is rotatably interposed between the exhaust pipes 11 and 11', and the other end of a coiled elastic body 13 is fixed to the rotary ring 14. This rotating ring 14 is in frictional contact with a roller 16 directly connected to a motor 15. Therefore, if the motor 15 is driven to rotate the rotary ring 14 via the rollers 16, the coiled elastic body 13 will be gradually twisted.

Moreover, as the rotating ring 14 further rotates, the torque applied to the elastic body 13 exceeds the frictional resistance between one end of the elastic body 13 and the friction ring 12, causing slippage between them, causing the coil to suddenly The shaped elastic body 13 will recover to its original state. - In the drawing, reference numeral 11' indicates an exhaust pipe that communicates the exhaust pipe 11 with a surplus processing device (not shown).

In the automatic deposit removal device of the present invention having the above configuration, when the reaction surplus is sucked into the surplus processing device through the exhaust pipes 11 and 11' from the reaction device force≧, the reaction surplus is removed from the coiled elastic body 13. It adheres to and accumulates on the surface. At this time, if the rotating ring 14 is rotated to twist the coil-shaped elastic body 13, the deposition surface will be distorted, and the deposit will be in a state where the elastic body 13 is easily peeled off or peeled off. Further, as the rotating ring 14 continues to rotate, the elastic body 13 releases the strain and rapidly recovers to its original state, and at this time, the deposits are completely peeled off from the elastic body 13. This peeled deposit is removed by suction air and processed by a surplus processing device. Therefore, the reaction conditions in the reaction vessel can be maintained constant without the evacuation conditions such as the amount of evacuation changing over time. In the above embodiment, a coil-shaped elastic body is used as the elastic body 13, but in the present invention, not only a coil-shaped elastic body but also a cylindrical elastic body can be used in the same manner, and the same effect as described above can be achieved. .

As described above in detail based on the embodiments, in the present invention, an elastic body is attached along the inner wall of the discharge passage, and deposits are peeled off from the elastic body by utilizing rapid torsional recovery of the elastic body. Therefore, it is possible to prevent the reaction surplus from adhering to and depositing on the discharge path. Therefore, the reaction conditions in the reaction vessel can now be maintained constant without changing the exhaust conditions such as the exhaust amount. In particular, the present invention
When applied to a reaction vessel with an optical fiber base material using the D method, the exhaust conditions remain unchanged, so the distribution of glass particles in the space from the oxyhydrogen flame parner to the seed rod can be maintained constant without changing over time. This makes it possible to continuously manufacture optical fiber preforms having a predetermined refractive index distribution.

[Brief explanation of the drawing]

FIG. 1 is a schematic structural diagram of a reactor for reacting an optical fiber base material using the VAD method, and FIG. 2 is a sectional view of an embodiment of the automatic deposit removal device of the present invention. In the figure, 11.11' is an exhaust pipe 12, a friction ring 13, a coiled elastic body 14, a rotating ring 15, and a motor 16 is a roller. Patent applicant: Sumitomo Electric Industries, Ltd. agent Patent attorney: Shibu Mitsuishi (1 other person)

Claims (1)

[Claims] An elastic body is installed along the inner wall of the discharge passage for exhausting reaction surplus from the reaction vessel, and a vibration mechanism is provided to twist the elastic body and then rapidly restore it to its original state, j# of the reaction surplus from the elastic body! An automatic deposit removal device characterized by peeling off deposits.