JP3065373B2 - Curing device for coating agent applied to optical fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for curing an ultraviolet curing type coating agent applied to an optical fiber.

[0002]

2. Description of the Related Art In order to prevent the occurrence of damage on the outer surface of an optical fiber or to bundle a plurality of optical fibers, a UV-curable coating agent (hereinafter simply referred to as "coating agent") is suitably used. 7 and 8 show a conventional coating agent curing apparatus. In this curing device, 1 is an optical fiber coated with a coating agent, 2 is a transparent pipe made of quartz that transmits ultraviolet rays, 3 is a mercury lamp mainly emitting ultraviolet rays, and 4 is an elliptical mirror made of glass or aluminum. And is fixed to the casing 5 via a support (not shown).

A coating device (not shown) is provided above the curing device, and an uncured coating agent is applied to the outer surface of the optical fiber 1 by the coating device. The uncured coating agent applied to the outer surface of the optical fiber 1 is cured by ultraviolet rays emitted from the mercury lamp 3 and the elliptical mirror 4 while the optical fiber 1 travels inside the light-transmitting pipe 2 from above to below. I do. The traveling speed of the optical fiber 1 is, for example,
It is set to 50m / min, and the mercury lamp 3 has a lighting power of 2KW
(Length 25 cm) are used.

[0004]

However, there is a demand for a high-speed processing in order to improve the production efficiency, and it has been studied to increase the traveling speed of the optical fiber from such a request. As the traveling speed increases, a lamp having a large lighting power is required. For example, it is necessary to similarly use two mercury lamps of about 4 KW (length 50 cm) in the above-described curing device.

However, a new problem has arisen with the use of a lamp having a large lighting power. That is,
For example, when the remaining amount of the coating agent is small in the coating apparatus in the preceding process, it is necessary to reduce the traveling speed of the optical fiber during irradiation, and in such a case, the optical fiber is irradiated with an excessive amount of light. As a result, the applied coating agent is overcured, and the outer surface of the optical fiber is burnt, which in turn lowers the production efficiency.

In order to solve such a problem, it is conceivable to use a lamp with a low input. However, a certain amount of lamp input is required from the viewpoint of the stability of irradiation light.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to speed up the curing process and to burn the outer surface of the optical fiber even when the running speed of the optical fiber is reduced. Gana rather, further light sources and Shi
It is an object of the present invention to provide an apparatus for curing a coating agent capable of sufficiently cooling a jitter .

[0008]

An apparatus for curing a coating agent applied to an optical fiber according to the present invention is a tube type extending in the vertical direction, which irradiates light to a traveling position of the optical fiber coated with an ultraviolet curing type coating agent. Light source and tube
A light irradiating mechanism composed of a reflection mirror in a shape of a light, a light-transmitting pipe disposed so as to surround the optical fiber, and a light reduction mechanism provided outside the light-transmitting pipe to adjust the amount of light emitted from the light irradiating mechanism to the optical fiber. it comprises an optical unit, said dimming means includes a dimming shutter plate-like blocking the light irradiated from the light irradiation mechanism to an optical fiber, Ri Na more a shutter driving mechanism for moving the dimming shutter in the vertical direction , before
The inside of the cylindrical reflecting mirror in the light irradiation mechanism is
Therefore, the room in which the tube-shaped light source is arranged, the light-transmitting pipe, and
Same as the room where the darkening shutter is located
Independent cooling air supply means is provided in each of the chambers.
Cage is moved upward to the dimming shutter from below
As a result, the optical fiber traveling from top to bottom
The illumination light to the bar is reduced .

[0009]

The dimming shutter is moved up and down by the shutter driving mechanism, and part of the irradiation light from the tube-shaped light source and the reflection mirror extending in the up and down direction is blocked, so that the irradiation light amount to the traveling optical fiber is reduced. Therefore, even when the traveling speed of the optical fiber is low, the coating agent does not overcure. Also, a cylindrical reflecting mirror
The inside is made of quartz plate, and the room where the tube type light source is arranged is transparent.
Divided into the room where the pipe and the dimming shutter are located
Independent cooling air supply means in each of the chambers
Cooling the light source and shutter
Can be

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a side sectional view of the curing device of the present embodiment, and FIG. 2 is a plan view taken along line AA of FIG.

The coating device curing apparatus of the present embodiment
A light irradiation mechanism 10 including a mercury lamp 11 extending vertically and an elliptical reflection mirror 12 having a cylindrical shape as a whole, and a translucent pipe 20 arranged around a traveling path of an optical fiber 90,
And a light-reducing means 30 provided outside the light-transmitting pipe 20. In the figure, 70 is a casing.

The curing device of the present embodiment is disposed below a coating device (not shown) in the preceding step. Optical fiber 90 with coating to be cured
Are running from top to bottom in a state where a plurality of them extend in parallel and are arranged in a tape shape. The diameter of the optical fiber 90 is, for example, 120 μm, and the traveling speed is set to, for example, 100 m / min.

The light irradiating mechanism 10 comprises a mercury lamp 11 extending in parallel with the traveling path of the optical fiber 90 and an elliptical reflecting mirror 12, and mainly irradiates the traveling position of the optical fiber 90 coated with the coating agent with ultraviolet rays. I do. In the curing device of this embodiment, the lighting power of the mercury lamp 11 is 4 KW (length 50 c).
m). The mercury lamps 11 are provided at two locations so as to face each other with the running path of the optical fiber 90 interposed therebetween, thereby enabling uniform irradiation to the bundle of the optical fibers 90 arranged and extended in a tape shape. .

The translucent pipe 20 is made of a quartz tube. At the lower end of the translucent pipe 20, a connector pipe 21 having a gas inflow hole 23 is connected, and at the upper end of the translucent pipe 20, a connector pipe 22 having a gas outflow hole 24 is connected, The inside of the light-transmitting pipe 20 is supplied with a nitrogen gas from the gas inflow hole 23 to form a nitrogen gas atmosphere, thereby promoting a curing reaction of the coating agent.

The light-reducing means 30 includes a light-reducing shutter 31 for blocking light emitted from the light irradiation mechanism 10 to the optical fiber 90, and a shutter driving mechanism 32 for moving the light-reducing shutter 31 in the vertical direction. Fiber optics by means 30
The irradiation light amount to 90 is adjusted.

The light-attenuating shutters 31 are aluminum plate-shaped shutters extending in the same direction as the traveling path of the optical fiber 90, and are provided at two locations so as to face each other with the traveling path of the optical fiber 90 interposed therebetween. The dimming shutter 31 is moved in the direction in which the mercury lamp 11 extends by the shutter driving mechanism 32, whereby a part of the irradiation light from the light irradiation mechanism 10 is blocked. Here, since the dimming shutter 31 moves upward from below, the irradiation light on the lower side is dimmed first. Since the irradiation light on the upper side is not dimmed, light irradiation immediately after the application of the coating agent can be ensured, and dripping of the uncured coating agent is prevented.

The shutter driving mechanism 32 is a light reducing shutter 31.
It is provided below. The shutter drive mechanism 32 is composed of a rodless cylinder driven by compressed air, and has a short length because it has no rod.

The amount of light applied to the optical fiber 90 can be adjusted by moving the light reducing shutter 31. That is, when the traveling speed of the optical fiber 90 decreases, as shown in FIGS. 3 and 4, when the piston 33 of the shutter drive mechanism 32 moves from the lowest point L to the highest point H by compressed air, the piston 33 is connected to the piston 33. The tip 31A of the light-attenuating shutter 31 moves to the intermediate level C of the mercury lamp. As a result, the irradiation light of the lower half of the mercury lamp 11 is blocked,
The amount of light applied to the traveling optical fiber 90 decreases. Therefore, the outer surface of the optical fiber 90 is not burned by the coating agent due to overcuring.

In FIG. 1 and FIG. 2, an area where the mercury lamp 11 is arranged (hereinafter referred to as “lamp chamber 50”) and an optical fiber are shown.
The translucent pipe 20 on which the bar 90 runs and the dimming shutter
The area where the 31 is disposed (hereinafter referred to as “work chamber 60”) is partitioned by the quartz plate 40. Cooling air is supplied to the lamp chamber 50 from a cooling air supply hole 51 (indicated by an arrow a), whereby the mercury lamp 11 is cooled. The cooling air that has cooled the mercury lamp 11 is exhausted to the outside of the casing 70 through the exhaust hole 52 and the exhaust hole 71 (indicated by an arrow b). On the other hand, cooling air is supplied to the work chamber 60 from the cooling air supply hole 61 (indicated by an arrow c). As described above, the cooling means for the work chamber 60 independent of the cooling means for the lamp chamber 50 cools both side surfaces of the dimming shutter 31. Therefore, the dimming shutter 31
Is sufficiently cooled, and thermal deformation or the like due to a rise in temperature is effectively prevented.

Although the embodiment of the present invention has been described above, the present invention is not limited to this. For example, FIG.
And a curing device having one mercury lamp 11 as shown in FIG.

[0021]

According to the present invention, the dimming shutter is moved up and down by the shutter driving mechanism, and a part of the irradiation light from the tube-type light source and the reflecting mirror extending in the up and down direction is blocked, and the light is transmitted to the traveling optical fiber. Irradiates less light.
Therefore, even when the traveling speed of the optical fiber is low, the outer surface of the optical fiber is not burned. Then, the speed of the curing process can be increased, and the production efficiency can be improved. In addition, the inside of the cylindrical reflecting mirror is made of quartz
The room where the light source is located, the translucent pipe and the
The room is divided into rooms in which
Independent cooling air supply means is provided in
And the shutter can be cooled sufficiently, further dimming
Since the shutter has a plate shape, the light-reducing shutter
Is sufficiently cooled, so that thermal deformation is effectively prevented.
You.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing one embodiment of a curing device of the present invention.

FIG. 2 is a plan view taken along a line AA in FIG. 1;

FIG. 3 is a side sectional view showing a state where a piston of a shutter drive mechanism is at a lowermost point in the curing device shown in FIG.

FIG. 4 is a side sectional view showing a state in which a piston of a shutter drive mechanism is at a highest point in the curing device shown in FIG.

FIG. 5 is a side sectional view showing another embodiment of the curing device of the present invention.

FIG. 6 is a plan view taken along a line BB in FIG. 5;

FIG. 7 is a side sectional view showing an example of a conventional curing device.

FIG. 8 is a plan view taken along line CC of FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical fiber 2 Translucent pipe 3 Mercury lamp 4 Elliptical mirror 5 Casing 10 Light irradiation mechanism 11 Mercury lamp 12 Reflecting mirror 20 Translucent pipe 21 Connector pipe 22 Connector pipe 23 Gas inlet hole 24 Gas outlet hole 30 Dimming means 31 Dimming shutter 32 Shutter drive mechanism 33 Piston 40 Quartz plate 50 Lamp room 51 Cooling air supply hole 52 Exhaust hole 60 Work chamber 61 Cooling air supply hole 70 Casing 71 Exhaust hole 90 Optical fiber

Continuation of the front page (56) References JP-A-62-262807 (JP, A) JP-A-62-158143 (JP, A) JP-A-62-222839 (JP, U) (58) Fields investigated (Int) .Cl. ⁷ , DB name) C03C 25/12

Claims (1)

(57) [Claims] 1. A light irradiation mechanism comprising a vertically extending tube-shaped light source and a cylindrical reflecting mirror for irradiating light to a traveling position of an optical fiber coated with an ultraviolet curing type coating agent, and surrounding the optical fiber. A light-transmitting pipe disposed therein; and a light-reducing means provided outside the light-transmitting pipe and configured to adjust the amount of light emitted from the light irradiation mechanism to the optical fiber. a dimming shutter plate-like blocking the illumination light to the optical fiber from the mechanism, Ri the dimming shutter Na more a shutter driving mechanism for moving up and down direction, tubular internal reflection mirror in the light irradiation mechanism includes a quartz plate
The room in which the tube-shaped light source is located, the translucent pipe and
And the room where the darkening shutter is located
In each case, an independent cooling air supply means is provided in each of the chambers.
And, to be moved upward said dimming shutter from below
To an optical fiber that travels from top to bottom
A curing device for a coating agent applied to an optical fiber, wherein the irradiation light of the light is reduced .