JP5621440B2 - Winding bobbin for optical fiber - Google Patents

Description

  The present invention relates to an optical fiber winding bobbin on which an optical fiber is wound when measuring the microbend loss of the optical fiber.

  The transmission loss of an optical fiber includes a loss due to a microbend, and this is caused by a slight fiber bending caused by a coating resin or the like. In order to measure this loss, conventionally, a fine mesh wire net is pasted on the surface of a take-up bobbin for optical fiber, and the optical fiber is wound on it, or the microbend characteristics due to temperature change are observed. However, a method of measuring the loss due to bending of the overlapping part with temperature change by wrapping around a winding cylinder made of quartz with low thermal expansion at a large pitch and changing from low temperature to high temperature in a constant temperature bath (non-patent Reference 1 etc.) was adopted.

Steven R. Schmid et al, “Development and Characterization of a Superior Class of Microbend Resistant Coating for Today ’s Networks”, Proceeding of the 58th International Wire & Cable Symposium, pp.72-77

As described above, when measuring the microbend loss of an optical fiber, a method of measuring the temperature characteristics by winding the optical fiber around a winding body made of quartz glass is employed. The reason why quartz is used for the material of the winding drum portion is that there is little thermal expansion and the microbend loss can be measured accurately. As shown in FIG. 3, in order to wind the optical fiber around the silica glass winding drum 501, it is necessary to mount the winding drum 501 on the winding shaft 505 of the winder 503 and rotate it. At this time, in order to hold the winding drum 501 and transmit the rotational force, a metal or resin shaft hole component 507 and a flange 509 are attached, and the winding drum 501 is attached to the shaft hole component 507 or the flange 509. The holding force was fixed, and the rotational force was transmitted by a combination of a kelepin 511 on the winding shaft 505 side and a kelepin pin 513 provided in the flange 509.
Therefore, when the temperature characteristics are measured, if the temperature is changed by putting the shaft hole part 507 and the flange 509 in the quartz glass winding drum 501 and changing the temperature, the quartz glass winding drum 501 In the case where the winding drum portion is held by the metal or resin shaft hole part 507 or the flange 509 having a large thermal expansion coefficient, the difference in thermal expansion when the quartz glass winding drum portion 501 is set to a high temperature or a low temperature. There was a risk of breakage. In order to avoid this breakage, the quartz glass winding drum 501 can be removed from the shaft hole part 507 and the flange 509 and placed in a thermostatic bath, but in that case, the quartz fiber should not be brought into contact with the floor. A dedicated jig for receiving the inner diameter of the glass winding drum 501 is required, which complicates the measurement preparation work and increases the entire measurement work time.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a take-up bobbin for an optical fiber that can prevent damage due to a difference in thermal expansion of the take-up drum made of quartz glass with other members. is there.

The above object of the present invention is achieved by the following configuration.
(1) A pair of rivets are fixed to both ends of the shaft hole component, and a cylindrical glass-made winding drum portion is sandwiched between the pair of ridges coaxially with the shaft hole component. An optical fiber winding bobbin fixed by
The shaft hole part and the flange are made of a material having a coefficient of thermal expansion different from that of the winding drum part,
A cushioning material that absorbs a difference in expansion due to heat between the winding drum portion, the shaft hole component, and the flange is in contact with each of the winding drum portion, the shaft hole component, and the flange, and the winding drum portion. An optical fiber take-up bobbin that is interposed between the shaft hole component and the flange.

  According to this optical fiber winding bobbin, the buffer material that absorbs the difference in expansion due to heat is interposed in the portion that holds the winding barrel made of quartz glass, and the shaft hole component expands outward in the radial direction. The stress acting on the quartz glass winding drum can be relieved by the axial expansion and contraction of the ridge spacing. For example, even if the shaft hole component expands radially outward, the displacement is absorbed by the cushioning material, and the stress in the direction of expanding the inner diameter of the quartz glass winding drum is significantly reduced. In addition, a cushioning material is inserted between the end surface of the quartz winding drum and the flange, which has hitherto been abutted, and even if the collar expands in the axial direction, the displacement is absorbed by the cushioning material. Is done. Thereby, even if the take-up bobbin for optical fibers is put in a thermostat as it is, the microbend loss can be measured without being damaged.

(2) The optical fiber winding bobbin according to (1), wherein the buffer material is an elastic body.

  According to this optical fiber winding bobbin, the displacement caused by the shaft hole part and the flange and the quartz glass winding drum due to temperature change can be repeatedly absorbed by the elastic deformation of the elastic body.

(3) The optical fiber winding bobbin according to (2), wherein the elastic body is silicon rubber.

  According to this take-up bobbin for optical fibers, silicon rubber that can withstand the temperature range set in the thermostat is selected as the elastic body. The temperature characteristics are usually measured in the temperature range of −60 ° C. to + 80 ° C. Therefore, compared with other rubbers such as butadiene rubber, silicon rubber is more suitable in terms of low temperature resistance, adhesion resistance, elasticity recovery, etc. Most suitable.

(4) The take-up bobbin for optical fibers according to any one of (1) to (3), wherein a plurality of the buffer materials are arranged in a circumferential direction of the take-up drum portion. Winding bobbin for optical fiber.

  According to the take-up bobbin for optical fiber, the buffer material is distributed and arranged in a balanced manner in the circumferential direction of the take-up drum portion, so that it is uniformly distributed in the circumferential direction on the take-up drum portion made of quartz glass due to the difference in thermal expansion. The acting stress can be relaxed.

  According to the optical fiber winding bobbin of the present invention, the cushioning material is interposed between the quartz glass winding drum and the flange and the shaft hole component so that the flange and the shaft hole component are heated at a high temperature. It can absorb the difference in thermal expansion due to expansion or shrinkage of the ridge spacing at low temperatures, and can prevent damage to the winding drum due to the difference in thermal expansion.

It is sectional drawing of the winding bobbin for optical fibers which concerns on this invention. It is an AA cross-sectional arrow view of FIG. It is the schematic diagram which represented notionally the conventional winding bobbin for optical fibers, and the winding machine used for the winding.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of a take-up bobbin for an optical fiber according to the present invention, and FIG. 2 is a cross-sectional view taken along line AA in FIG.
The optical fiber winding bobbin 11 according to the present embodiment is mounted on a winding shaft 505 of the winding machine 503 similar to the conventional one shown in FIG.

  The optical fiber winding bobbin 11 includes a shaft hole part 13 into which the winding shaft 505 is inserted, flanges 15 at both ends of the shaft hole part 13, and a silica glass winding cylinder around which the optical fiber is wound. Part 17. The shaft hole component 13 includes a shaft portion 19 and small diameter flanges 21 fixed to both ends thereof by welding or the like. A flange 15 is fixed to the small diameter flange 21.

  The shaft part 19, the small diameter flange 21, and the flange 15 are made of metal or resin. That is, the shaft hole part 13 and the flange 15 are made of a material having a different coefficient of thermal expansion from that of the winding drum part 17.

The flange 15 fixed to the shaft hole component 13 is fixed to the small diameter flange 21 fixed to the end of the shaft portion 19 by a hexagon socket head screw 27. The hexagon socket head screw 27 is inserted from the outside of the flange 15 and screwed into a female screw portion 29 formed in the small diameter flange 21.
In addition, in order to attach to a winder, you may form the pin pin hole engaged with the said pin pin 511 in either the right or left collar 15, or both. Moreover, you may provide another attachment mechanism which opened the kele pin hole which engages with the said kele pin 511 on the bobbin outer side.

  Between the pair of flanges 15, the above-described quartz glass winding drum portion 17 formed in a cylindrical shape is sandwiched and fixed coaxially with the shaft hole component 13. In the conventional structure, the take-up drum portion 17 is directly held in contact with the flange and the shaft hole component. However, in the optical fiber take-up bobbin 11 according to the present embodiment, the buffer material 37 is interposed therebetween. . The winding drum portion 17 is sandwiched between the flanges 15 via the cushioning material 37, so that the movement in the axial direction is reduced. Further, the buffer material 37 also reduces the movement of the winding drum portion 17 in the radial direction. In addition, the interposition means to be positioned between members and to have a desired shape. In the present embodiment, it is positioned between the flange 15 and the shaft hole component 13 and the winding drum portion 17.

  An annular recess 41 shown in FIG. 1 is formed on the inner facing surfaces 39 of the left and right flanges 15 along the outer periphery of the small diameter flange 21. Moreover, the outer peripheral part of the small diameter flange 21 is gear-shaped, and is formed so that the clamping wall 43 protrudes radially outward. A plurality (six in this example) of the sandwiching walls 43 are formed at a predetermined interval (interval of 60 ° angle) in the circumferential direction. A buffer material 37 is held on each clamping wall 43. That is, in the present embodiment, the cushioning material 37 that absorbs the thermal expansion difference between the winding drum portion 17 and the flange 15 and the shaft hole component 13 is provided between the winding drum portion 17 and the flange 15 and the shaft hole component 13. In FIG. 2, a plurality of pieces are interposed in the circumferential direction.

  As shown in FIG. 1, the cushioning material 37 is a substantially central portion of the radial dimension of the heel, and the radially inner portion is a thick portion 45 and the outer portion is a thin portion 47. A stepped portion 49 is formed between the thick portion 45 and the thin portion 47. That is, the buffer material 37 is L-shaped. The step portion 49 abuts on the inner peripheral surface 51 of the winding drum portion 17. That is, the buffer material 37 has one end in the radial direction in contact with the holding wall 43, and the stepped portion 49 contacts the inner peripheral surface 51 of the winding drum portion 17 and the end surface 53 of the winding drum portion 17. Thereby, the movement of the winding drum portion 17 in the radial direction is relaxed by the thick portion 45, and the movement in the axial direction is relaxed by the thin portion 47.

  The buffer material 37 is preferably an elastic body. The elastic body is more preferably silicon rubber.

Next, the operation of the optical fiber winding bobbin 11 having the above configuration will be described.
In the optical fiber take-up bobbin 11, a buffer material 37 that absorbs a difference in expansion due to heat is interposed in a portion that holds the take-up drum portion 17, and is wound by expansion and contraction due to heat of the shaft hole component 13 and the flange 15. The stress acting on the trunk portion 17 is relaxed. For example, even if the shaft hole component 13 expands radially outward, the displacement is absorbed by the buffer material 37, and the stress in the direction of expanding the inner diameter of the winding drum portion 17 is absorbed by the thick portion 45 and is markedly increased. Get smaller.

  Further, the thin-walled portion 47 of the cushioning material 37 is interposed between the end surface 53 of the winding drum portion 17 and the flange 15 that have hitherto been contacted, and even if the flange 15 expands and contracts in the axial direction. The thin portion 47 absorbs the displacement, and the stress applied to the end of the winding drum portion 17 is relaxed. Thereby, even if the winding bobbin 11 for optical fibers is put into a thermostat as it is, it becomes possible to measure microbend loss without being damaged.

  The displacement generated between the shaft hole component 13 and the flange 15 and the winding drum portion 17 due to the temperature change can be repeatedly absorbed by the elastic deformation of the buffer material 37. As this kind of elastic body, rubber or the like that can withstand the temperature range set in the thermostat is selected. In practice, since the temperature range is -60 ° C to + 80 ° C, butadiene rubber and silicon rubber are suitable materials for low temperature resistance, but silicon rubber that excels in adhesion resistance and elasticity recovery is more suitable. Preferred.

  Further, in the optical fiber winding bobbin 11, the cushioning material 37 is distributed and arranged in a balanced manner in the circumferential direction of the winding drum portion 17, so that the quartz glass winding drum is uniformly distributed in the circumferential direction. The stress acting on the part can be relaxed.

  Therefore, according to the take-up bobbin 11 for an optical fiber according to the present embodiment, the cushioning material 37 is interposed between the take-up drum portion 17 and the flange 15 and the shaft hole component 13, so that a high temperature or a low temperature can be obtained. Thus, the difference in thermal expansion can be absorbed, and damage to the winding drum portion 17 due to the difference in thermal expansion can be prevented.

Create a take-up bobbin for an optical fiber with the same configuration as the above-mentioned embodiment, wind the optical fiber on it, measure the microbend loss by changing from low temperature to high temperature in a constant temperature bath, and break the bobbin at that time The presence or absence of was investigated.
Note that silicon rubber having a rubber hardness of 45 degrees was used as the buffer material.
The optical fiber winding bobbin around which the optical fiber was wound around the winding body and the optical fiber was wound was housed in a thermostatic bath for 120 hours, and was changed from a low temperature to a high temperature. The temperature range changed was from −60 ° C. to + 80 ° C. This change in temperature was defined as one cycle, and was repeated six times at a rate of once every 20 hours.
Such measurement of microbendros was repeated several times, but the quartz glass winding drum was not damaged.
In addition, the crushing of the silicon rubber of the take-up bobbin for the optical fiber taken out from the thermostatic chamber was measured. In the length direction, 9% crushing was confirmed at a rubber thickness of 5.5 mm with respect to the tube length of 220 mm of the winding drum portion. Because of this, by interposing the cushioning material between the winding drum portion and the flange and shaft hole parts, the difference in expansion between the members caused by the temperature difference is absorbed by the cushioning material. It was found that no damage occurred.

DESCRIPTION OF SYMBOLS 11 Winding bobbin for optical fibers 13 Shaft hole component 15 鍔 17 Winding drum part 37 Buffer material

Claims (4)

A pair of flanges are fixed to both ends of the shaft hole component, and a cylindrical glass-made winding drum portion is coaxially sandwiched and fixed between the pair of flanges. An optical fiber take-up bobbin,
The shaft hole part and the flange are made of a material having a coefficient of thermal expansion different from that of the winding drum part,
A cushioning material that absorbs a difference in expansion due to heat between the winding drum portion, the shaft hole component, and the flange is in contact with each of the winding drum portion, the shaft hole component, and the flange, and the winding drum portion. An optical fiber take-up bobbin that is interposed between the shaft hole component and the flange. A take-up bobbin for an optical fiber according to claim 1,
The take-up bobbin for an optical fiber, wherein the buffer material is an elastic body. A take-up bobbin for an optical fiber according to claim 2,
A take-up bobbin for an optical fiber, wherein the elastic body is silicon rubber. The take-up bobbin for an optical fiber according to any one of claims 1 to 3,
A plurality of the buffer materials are arranged in the circumferential direction of the winding drum part, and the winding bobbin for optical fiber is characterized in that

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