JPS6045135B2 - Optical fiber drawing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention involves heating and softening a glass base material for forming an optical fiber, drawing it into an optical fiber, and feeding the optical fiber obtained by the drawing to a winding drum. The present invention relates to an optical fiber drawing device configured to wind the optical fiber onto a winding drum.

Conventionally, as shown in FIG. 1, this kind of optical fiber drawing apparatus has a rod-shaped glass base material 1 for forming an optical fiber, and a chuck 2 for gripping it, and a feed mechanism 3 connected to the chuck 2, and a heater 4 installed therein. placed in a furnace 5 for heating and softening the base material,
As a result, the glass preform 1 for forming an optical fiber is heated and softened at its tip and drawn into an optical fiber 6, and the optical fiber 6 obtained by the drawing is housed in a coating material 8 for a protective film. Next, the optical fiber 10 is passed through a coating baking furnace 9 to form an optical fiber main body, and an optical fiber 10 with a protective coating applied to the outer periphery is obtained. 11 and a presser roller 12 that can be rolled into contact with the optical fiber 10 to obtain the optical fiber continuously. The measured output is supplied to a capstan drive control circuit (not shown), and based on the measured output, an output representing an error in the diameter of the optical fiber main body of the optical fiber 10 from a predetermined diameter value is obtained. and controlling the rotational speed of the capstan 11 based on the output thereof, thus obtaining the optical fiber 10 having a predetermined diameter and having a protective coating attached to the outer periphery of the optical fiber body,
A configuration has been proposed in which the optical fiber 10 is fed to a winding drum 14 and wound onto the winding drum 14.

However, when the optical fiber 10 obtained by the optical fiber drawing apparatus has a defect due to some reason, the apparatus is equipped with a means for detecting the missing section. Since the defect was not detected, the optical fiber 10 could not be wound onto the winding drum 14 to be inspected for defects. .

Conventionally, in order to obtain the optical fiber 10 obtained by the above-mentioned optical fiber drawing apparatus and inspected for defects, the optical fiber 10 after being wound on the winding drum 14 was used. For this reason, the optical fiber 10 obtained by the above-mentioned optical fiber drawing apparatus is inspected for defects. It took a lot of time and effort to obtain the desired results. Therefore, the present invention
The optical fiber drawing apparatus described above in FIG. 1 heats and softens a glass base material for forming an optical fiber, draws it into an optical fiber, and feeds the optical fiber obtained by the drawing to a winding drum. In an optical fiber drawing device designed to wind this onto the winding drum, the optical fiber obtained on the winding drum is inspected for defects. The purpose is to propose a novel optical fiber drawing device that can automatically obtain optical fibers during the process of winding them onto a winding drum, which will become clear from the detailed description of embodiments of the present invention below. Will. FIG. 2 shows an embodiment of an optical fiber drawing device according to the present invention based on the optical fiber drawing device described above in FIG. Although this is omitted, in the configuration described above in FIG. −
It has the same configuration as the case shown in FIG. 1, except that it includes a defect detection device 20 and a dryer 40 arranged as necessary on the winding drum 14 side.

In this case, the defect detection device 20 operates as shown in FIG. 3”
The optical fiber 10 that has been continuously obtained by passing between the capstan 11 and the presser roller 12 is wrapped around the back-tensioned payout pulley 21 for about 114 turns, and then passed through the payout pinch pulley 22. Wrap around it approximately half way around it, and then turn the feeding pulley 21 again around that 1
Then, the pulley 25, which is disposed above and facing the water 24 contained in the container 23, is wrapped around it approximately 114 times, and then the water 24 is placed in the water 24. The pulley 26 arranged in the water-repellent 24 is wrapped around the pulley 26 for about 114 turns, and then the pulley 27 similarly arranged in the water-repellent 24 is wrapped around the pulley 26 for about 114 turns.
The pulley 1J28 placed on the water 24 facing the water 24 is covered for approximately 114 turns, and then the pullout pulley IJ29, which is loaded with a constant torque, is covered approximately 114 times. 114 times, then pull out pinch pulley 3
0 for approximately half the circumference, and then pull out the pulley 29.
Wrap it again for about 114 times, and put it in the dryer 40 times.
The fiber is fed to the winding drum 14 through the water 24, thereby giving the optical fiber 10 the required tension as a defect detection tension over the length between the pulleys 26 and 27 arranged in the water 24. It also has an ultrasonic detector 32 disposed within the water 24 which is adapted to receive known ultrasonic waves and derive a corresponding electrical output;
Therefore, the ultrasonic detector 32 applies a tension for defect detection to the optical fiber 10, so that the optical fiber 1
If there is a defect in the optical fiber 10, the defect becomes apparent and the ultrasonic waves generated from the defect position of the optical fiber 10 are detected.

The above is an example of the optical fiber drawing apparatus according to the present invention. According to such a configuration, the light obtained through the capstan 11 and the presser roller 12 in the configuration described above in FIG. A defect detection device 20 arranged on the way of feeding the fiber 10 to the winding drum 14 and the winding drum 1
It is clear that the optical fiber 10 can be obtained by winding it on the winding drum 14 since it is the same as the case shown in FIG. 1 except that the dryer 40 is provided on the fourth side. In this case, a means for applying tension for defect detection over a required length to the optical fiber 10 including the pulleys 21, 22, 25 to 28, 29, and 30, and a means for applying tension for defect detection to the optical fiber 10 including the pulleys 21, 22, 25 to 28, 29, and 30, and water 24 and Optical fiber 1 including acoustic wave detector 32
Since the defect detection device 20 is equipped with a means for detecting ultrasonic waves generated by the optical fiber 10 when the optical fiber 10 has a defect by applying a defect detection tension to the Therefore, if the optical fiber 10 is found to be defective for some reason, it is possible to obtain an output that allows the defect to be detected.

Therefore, according to the optical fiber drawing apparatus of the present invention described above,
By using the output obtained from the defect detection device 20 that detects the defect when the optical fiber 10 has a defect, the optical fiber 10 obtained by being wound on the winding drum 14 is detected to have a defect. This can be automatically obtained in the process of being wound onto the winding drum 14 as a result of inspection.

Further, the defect detection device 20 detects a defect in the optical fiber 10 by receiving ultrasonic waves generated when the defect becomes apparent when the optical fiber 10 has a defect. Therefore, it is inevitable that damage may be caused to the optical fiber 10 in order to obtain an output capable of detecting defects. This is even more true since the optical fiber 10 is passed through the water 24 as described above, and defects are detected by receiving the ultrasonic waves generated in the water 24. It is something. As described above, according to the present invention, the optical fiber obtained on the winding drum can be automatically obtained in the process of being wound on the winding drum as having been inspected for defects. It has the great feature that it does not require any time or effort, and it does not have the disadvantage of causing damage to the optical fiber.

The above description is merely an example of the present invention, and for example, the pulleys 21 and 22 in the defect detection device 20 described above are described.
Both sets 29 and 30 are replaced with sets of capstans and presser rollers so that the optical fiber 10 is passed between the capstans and presser rollers of both sets. Tension for defect detection is applied to the optical fiber 10 by rotating the capstan of the set of presser rollers at a slightly higher circumferential speed than that of the capstan of the set of pulleys 21 and 22 and the capstan of the set of presser rollers. You can also do things like
Various other modifications may be made without departing from the spirit of the invention.

[Brief explanation of drawings]

Figure 1 is a route map showing a conventional optical fiber drawing device;
The figure is a route map showing an example of an optical fiber drawing apparatus according to the present invention, and FIG. 3 is a route map showing an example of its essential parts. In the figure, 1 is a glass base material for forming optical fibers, 2 is a chuck,
3 is a feeding mechanism, 4 is a heater, 5 is a furnace for heating and softening the base material, 6
1 is an optical fiber, 7 is a coater, 8 is a protective film coating material, 9 is a coating baking furnace, 10 is an optical fiber, 11 is a capstan, 12 is a presser roller, 13 is a wire diameter measuring device, 14 is a winding drum, 2J0 is a defect detection device, 21 is a feeding pulley, 2
2 is a feeding pinch pulley, 23 is a container, 24 is water, 25~
28 is a pulley 18, 29 is a drawer pulley, 30 is a drawer pinch pulley, 32 is an ultrasonic detector, and 40 is a dryer.

Claims (1)

[Claims] 1. A glass base material for forming an optical fiber is softened by heating and drawn into an optical fiber, and the optical fiber obtained by the drawing is fed to a winding drum and wound on the winding drum. The optical fiber drawing apparatus has been provided with a defect detection device disposed on the way of feeding the optical fiber obtained by the drawing to the winding drum, and the defect detection device detects the defects required for the optical fiber. means for applying defect detection tension over the length of the optical fiber; and ultrasonic waves generated by the optical fiber when the optical fiber has a defect by applying the defect detection tension to the optical fiber by the means. An optical fiber drawing device characterized by having a means for detecting.