JPH1183672A - Optical fiber-screening apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To apply distortion to many side faces of an optical fiber and enable highly reliable strict tests by arranging at least one inclined turn pulley between a main capstan and a turn pulley. SOLUTION: Inclined turn pulleys 11-14 are arranged with having a rotation center axis inclined by approximately ±45 deg. to a main capstan 3 and a turn pulley 4. An optical fiber 2 is sent out from a sending part 1 into an apparatus and wound to a wind part 8 via the main capstan 3, the first - fourth inclined turn pulleys 11-14, the turn pulley 4, a screening dancer 6 and a screening capstan 5. At this time, a tensile test is conducted to the optical fiber 2 between the main capstan 3 and the screening capstan 5. When the optical fiber 2 passes the inclined turn pulleys 11-14, a distortion is applied to a side face of the optical fiber 2, so that the test can be carried out more strictly with high reliability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber screening apparatus.

[0002]

2. Description of the Related Art Defects such as microcracks may be observed on the surface of an optical fiber, and when these defects grow, the strength of the optical fiber is remarkably reduced, leading to disconnection. Therefore, in the final stage of the manufacturing process, a tensile test (screening test) is performed by a screening device having a mechanism for applying a predetermined strain to the optical fiber for a predetermined time, and the disconnected optical fiber is excluded.

FIG. 4 is a schematic view of a conventional optical fiber screening apparatus. The optical fiber screening apparatus includes a sending unit 1, a main capstan 3, a turn pulley 4, a screening capstan 5, a screening dancer 6, a weight 7, and a winding unit 8.

[0004] The optical fiber 2 is sent out of the sending section 1 into the apparatus, and the main capstan 3, the turn pulley 4, the screening dancer 6, and the screening capstan 5 are provided.
, And wound up by the winding unit 8, and a tensile test is performed in a section between the main capstan 3 and the screening capstan 5.

At this time, in order to guarantee the strength of the optical fiber, it is necessary to apply a certain amount of distortion for a certain time. The distortion amount, which is one of the conditions, is given by the difference in peripheral speed between the main capstan 3 and the screening capstan 5,
It can be provided by a weight 7 attached to the screening dancer 6 or the like.

[0006] The distortion application time, which is another condition, is a value obtained by dividing the optical fiber traveling length in the section between the main capstan 3 and the screening capstan 5 by the optical fiber traveling speed. Is about 1 second. Therefore, when a screening test is performed at an optical fiber traveling speed of 600 m / min, an optical fiber traveling length of 10 m is required.

In order to obtain this optical fiber travel length, a plurality of turn pulleys 4 are arranged in the same plane within the section between the main capstan 3 and the screening capstan 5, and the optical fiber 2 is folded by these turn pulleys 4. Meandering.

[0008]

In the distortion applying section between the main capstan 3 and the screening capstan 5,
A certain strain is applied to the optical fiber 2, and there are two types of the strain, one of which is a uniaxial tension applied to the optical fiber 2 between the turn pulley 4 and another turn pulley 4. The other type of strain is a compound strain in which bending strain and tensile strain are applied while being bent to a certain bending radius by the turn pulley 4.

As the condition for imparting strain to the optical fiber, the latter compound strain is more severe, and disconnection frequently occurs during passage through the turn pulley 4. Therefore, it can be said that the strength of the optical fiber to be tested should be evaluated by the composite strain.

However, in the screening apparatus shown in FIG. 4, since the turn pulleys 4 are all arranged on the same plane, there is a problem in evaluating the composite distortion.

FIG. 5 is an explanatory view showing the state of an optical fiber running on a turn pulley 4 in a conventional apparatus. In this conventional apparatus, since the turn pulley 4 is arranged in the same plane, the optical fiber 2 Can only distort two sides. That is, since the upper turn pulley applies strain only to the upper side of the optical fiber 2, and the lower turn pulley applies strain only to the lower side of the optical fiber 2, defects existing on other side surfaces are inspected. There was a problem that it was not possible.

Accordingly, an object of the present invention is to solve the above-mentioned disadvantages of the prior art and to provide a strict and reliable optical fiber screening test apparatus capable of imparting distortion to multiple sides of an optical fiber. Is to do.

It is another object of the present invention to provide an optical fiber screening test apparatus capable of performing high-speed screening in a small space while securing the running length of the optical fiber.

[0014]

In order to achieve the above object, the present invention provides an optical fiber sending section, a main capstan, a turn pulley, a screening dancer, a weight, a screening capstan, and an optical fiber winding. In the optical fiber screening device that is provided in series and inspects mechanical strength by applying strain to the optical fiber, between the main capstan and the turn pulley,
Disposing the optical fiber from multiple directions by arranging at least one inclined turn pulley.

[0015]

FIG. 1 is a schematic view showing an embodiment of an optical fiber screening apparatus according to the present invention, and FIG. 2 is a top view of the apparatus. The apparatus includes a delivery unit 1, a main capstan 3, a first inclined turn pulley 11, a second inclined turn pulley 12, a third inclined turn pulley 13, a fourth inclined turn pulley 14, a turn pulley 4, a screening cap. Stan 5, screening dancer 6,
Each of the inclined turn pulleys 11, 12, 13, and 14 includes a weight 7 and a winding unit 8, and the center axis of rotation of each of the inclined turn pulleys 11, 12, 13, and 14 is inclined by ± 45 degrees with respect to the main capstan 3 and the turn pulley 4.

The optical fiber 2 is sent out of the sending section 1 into the apparatus, and the main capstan 3, the first inclined turn pulley 11, the second inclined turn pulley 12, the third inclined turn pulley 13, the fourth inclined pulley 13, Inclined turn pulley 14,
The film passes through the turn pulley 4, the screening dancer 6, and the screening capstan 5, and is wound by the winding unit 8. At this time, the optical fiber 2 is subjected to a tensile test in the section between the main capstan 3 and the screening capstan 5. The amount of strain and the time of strain application, which are the conditions of the tensile test, are the same as in the conventional case.
It differs from the prior art in that 12, 13, and 14 are used.

FIG. 3 is a sectional view of the optical fiber 2.
(A) shows the state at point X in FIG. 1 (the state before passing through the first inclined turn pulley 11), and (b) shows the state at point X ′ in FIG. 1 (first state). Inclined turn pulley 11
After passing through). Symbols A to H are attached to the outer periphery so that the position around the optical fiber 2 can be specified.

Since the rotation plane of the first inclined turn pulley 11 includes the straight line connecting A and C in the optical fiber sectional view of FIG. 3A, the rotation plane passes through the first inclined turn pulley 11. In the optical fiber, a strain is applied to the side surface A in FIG. On the other hand, the posture of the optical fiber 2 after passing through the first inclined turn pulley 11 is as shown in FIG. 3B, and therefore, when the optical fiber 2 passes through the second inclined turn pulley 12, FIG. Is distorted on the side surface B.
Similarly, the side surface C is distorted when passing through the third inclined turn pulley 13, and the side surface D is distorted when passing through the fourth inclined turn pulley 14.

Behind the fourth inclined turn pulley 14, there are two turn pulleys 4, 4 between the screening capstan 5 and these turn pulleys 4, 4.
As a result, strain is applied to the side surfaces E and F of the optical fiber.

Therefore, in the conventional apparatus, distortion can be applied only to two sides, but in the present embodiment, distortion can be applied to six sides, so that a more strict and reliable test is performed. be able to.

Further, if a turn pulley inclined at 90 degrees is added to the apparatus of the present invention, distortion can be applied to the side surfaces G and H of the optical fiber described with reference to FIG. It becomes possible.

Further, in this embodiment, the turn pulley is
By arranging the turn pulley at an angle of 45 degrees, it is possible to obtain the same travel length with a width of 1 / √2 as compared with the case where the turn pulley is arranged in the same plane, and it is possible to reduce the size of the entire apparatus.

In the present embodiment, each of the inclined turn pulleys 11 to 14 has a center axis of rotation inclined by ± 45 degrees with respect to the main capstan 3 and the turn pulley 4, but this inclination is particularly limited to this value. It is not something that can be done.

[0024]

According to the present invention, the following remarkable effects can be obtained.

(1) Strain can be applied to multiple sides of the optical fiber, and a strict and reliable screening test can be performed.

(2) By arranging the turn pulleys at an angle, the size of the entire screening apparatus can be reduced as compared with the case where the turn pulleys are arranged in the same plane.

[Brief description of the drawings]

FIG. 1 is a schematic view showing one embodiment of an optical fiber screening apparatus of the present invention.

FIG. 2 is a top view of FIG.

3A and 3B are cross-sectional views of the optical fiber 2, wherein FIG. 3A shows a state at a point X in FIG. 1, and FIG. 3B shows a state at a point X ′ in FIG.

FIG. 4 is a schematic view of a conventional device.

FIG. 5 is an explanatory diagram showing a state of an optical fiber traveling on a turn pulley in a conventional device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sending part 2 Optical fiber 3 Main capstan 4 Turn pulley 5 Screening capstan 6 Screening dancer 7 Weight 8 Winding part 11 First inclined turn pulley 12 Second inclined turn pulley 13 Third inclined turn pulley 14 Fourth Inclined turn pulley

Claims (1)

[Claims] 1. An optical fiber sending section, a main capstan,
Turn pulley, screening dancer, weight,
Screening capstan, optical fiber winding unit is provided in a series, in an optical fiber screening device that applies a strain to the optical fiber and inspects the mechanical strength,
An optical fiber screening apparatus, wherein at least one inclined turn pulley is disposed between the main capstan and the turn pulley to apply strain to the optical fiber from multiple directions.