JP4327015B2 - Elongated strip mounted on optical fiber and manufacturing method thereof - Google Patents

Description

TECHNICAL FIELD The present invention relates to an optical fiber-mounted elongated strip that is mounted on a structure or a structural member and is used for detecting the amount of deformation thereof, and a method for manufacturing the same. Specifically, the optical fiber is mounted in a tensioned state. The present invention relates to an optical fiber-mounted long strip suitable for the above and a method for manufacturing the same.
Such an optical fiber-equipped elongated strip is easy to use as an optical fiber sensor because it conforms to the outer surface shape of the mounting object based on its flexibility, and uses, for example, Brillouin scattered light from an optical fiber. BOTDR (Brillouin Optical Time Domain Reflectometry) that measures the strain distribution of the object to be measured along the longitudinal direction of the optical fiber, or along the longitudinal direction of the optical fiber using Raman scattered light of the optical fiber It is useful as a measurement terminal (detector / detection end) when performing ROTDR (Raman Optical Time Domain Reflectometry) for measuring the temperature distribution of the measured object.

  As a technique of installing a long optical fiber at a monitoring target location in order to monitor environmental condition fluctuations such as landslides, the optical fiber is fixed in a state where a longitudinal extension strain is applied, that is, in a state where a tension is applied (for example, Patent Document 1), and a structure in which the surface of a structure is covered with an aggregated reaction curable resin while applying tension to the optical fiber (see, for example, Patent Document 2) are known. None of these are equipped with a flexible long support body or a long reaction force body, and when fixing or covering, apply tension by pulling the optical fiber directly from both sides, The object to be mounted is used as a support or reaction body after fixing and covering.

  Moreover, an optical fiber-containing adhesive tape configured by coating an optical fiber with an adhesive tape is also known (see, for example, Patent Document 3). This optical fiber-attached adhesive tape is used by sticking it to a railroad crossing barrier, etc. The tape part is not necessarily a flexible long support, but even if it is attached, tension is applied to the optical fiber. It is not configured such that a reaction force body is provided. The purpose of use is to detect when the optical fiber breaks due to breakage of the barrier, etc., and therefore, the strain distribution in the longitudinal direction of the optical fiber cannot be measured without breaking.

JP 2001-296112 A (first page, FIG. 2-3) JP 2002-131024 (page 1-2, FIG. 1) JP 63-304205 A

However, it is convenient to attach the optical fiber by attaching or winding an adhesive tape because the construction is simple and inexpensive.
On the other hand, if tension is applied to the attached optical fiber, not only compression deformation can be measured, but also the insensitive deformation area due to the extra length (sag) due to thermal expansion does not appear, and a slight elongation deformation is also possible. Since it can be measured accurately, its application range and application range are wide.
Therefore, development of an optical fiber sensor having both advantages is required.

  However, since the conventional method used to apply tension to the optical fiber pulls the optical fiber from both sides, a large-scale tool is required for this purpose, and it is installed along a linear installation or a guide groove. It is not compatible with construction methods such as tape application or winding. If used simply, it is a method of tape affixing or wrapping, and not only the convenience but also the high adaptability to the outer shape of the mounting object is lost, and the tension of the optical fiber is the applied tension However, this may be inconvenient because it may not be maintained for a sufficiently long period of time.

  Therefore, if a long strip material having flexibility such as tape is attached to or wrapped around an object to be mounted or strain-measured, it is not necessary to use a tool or jig. As a result of attaching the long member, it is naturally desired that the optical fiber is mounted and that the optical fiber is properly tensioned. And for that purpose, while supporting the long optical fiber in a state in which the flexibility of the optical fiber is not impaired and easy to mount, the optical fiber is utilized by utilizing the adaptive deformation to the outer shape of the mounting object. It is a technical problem to devise an optical fiber mounting structure so that tension can be applied to the fiber.

  The long strip of optical fiber according to the present invention (initial claim 1) was created to solve such a problem, and the optical fiber is attached to a flexible long support. An optical fiber mounting long strip mounted in a form or in an embedded form, comprising a long reaction body for applying tension to the optical fiber (hereinafter referred to as a long reaction body), The long reaction force body and the optical fiber strand are combined in a mutually restrictive relationship to form a composite functional body, and the optical fiber strand is mounted in the form of the composite functional body. Features. The expression composite function body has a function of combining an optical transmission function using an optical fiber and a tension applying function using a long reaction force body in addition to a morphological composite in which both elements are coupled in a mutually restrictive relationship. This composite also refers to the configuration embodied at the same time.

Moreover, the optical fiber mounting long strip of the present invention (initial claim 2) is the optical fiber mounting long strip of the initial claim 1, and the long support is made of a hard resin. It consists of a tape.
Here, the hard resin refers to a resin that has a high elastic modulus of 70 to 80 kN / cm ² or more and is not easily deformed, and representative examples thereof include polyimide, polyamide, polyester, polypropylene, and high-density polyethylene. It can be illustrated.

Furthermore, the optical fiber mounting long strip of the present invention (initial claim 3) is the optical fiber mounting long strip of the above-mentioned initial claim 1, and the long support is a plurality of strips. It consists of a tape in which glass fibers are arranged in an aligned form or in a braided form.
In addition, it is desirable to use what is called a long fiber (fiber which has a length which can be wound up) as glass fiber. In addition to the glass fiber, the tape may be a compound containing a resin as a joint agent, or a binder or sealant (that is, FRP).

Moreover, the optical fiber mounting long strip of the present invention (initial claim 4) is the optical fiber mounting long strip of the first to third aspects of the present invention, and further, the long reaction force body is a single unit. It consists of one or more glass fibers, and these or these glass fibers are arranged along the optical fiber strand.
Moreover, the optical fiber mounting long strip (initial claim 5) of the present invention is the optical fiber mounting long strip according to the above-mentioned initial claims 1 to 4, and further, the long support is the long strip. It also serves as a scale reaction force body.

  Moreover, the optical fiber mounting long strip (initial claim 6) of the present invention is the optical fiber mounting long strip according to the above-mentioned initial claims 1 to 5, and further, the optical fiber in the composite functional body. The element wire and the long reaction body are bonded to each other by an adhesive cured product. The coupling may be performed in a form in which the optical fiber and the long reaction force are directly facing each other, or between the optical fiber and the long reaction force. It may be performed in a form in which a hard spacer is interposed. Further, the cured adhesive product may be a reaction cured product such as an epoxy resin, or a solidified product obtained by heat-melting and cooling a hot-melt adhesive such as EEA (ethylene ethyl acrylate copolymer resin). May be.

  Moreover, the optical fiber mounting long strip (initial claim 7) of the present invention is the optical fiber mounting long strip according to the above-mentioned initial claims 1 to 6, and further, the optical fiber in the composite functional body. The element wire and the long reaction force body are connected to each other at a large number of connecting points that are connected in a stepping stone shape. No coupling is performed between these coupling points, and the portion sandwiched between the coupling points is in a non-bonded state.

  Moreover, the optical fiber mounting elongate body (initial claim 8) of the present invention is the optical fiber mounting elongate body according to the above-mentioned initial claim 7, and further in the uncoupled state, A separator member is interposed between the optical fiber and the long reaction force body. For example, a fluororesin is useful as the material for the separator member.

  Moreover, the optical fiber mounting elongate body (initial claim 9) of the present invention is the optical fiber mounting elongate body according to the above-mentioned initial claims 1 to 8, and further, the optical fiber in the composite functional body Regarding the overlapping direction (stacking direction) of the strand and the long reaction force body, the distance between the core of the optical fiber strand and the core of the long reaction force (that is, the distance between the core and the core) is the optical fiber. It is equal to or greater than the sum of the thickness of the strand and the thickness of the long reaction force body (that is, the total thickness of both), and in the longitudinal direction of the composite functional body, The normal length of the force body is longer than the normal length of the optical fiber.

  As a result, a normal length obtained by adding an extra length to the normal length of the optical fiber is loaded on the long reaction force body. When the body is left in a free state without applying an external force, it curls in such a manner that the optical fiber strand is on the inner peripheral side and the long reaction force body is on the outer peripheral side. Further, when the curl is unwound and straightened, tension is generated in the optical fiber even when the external force for uncurling is not tension. This optical fiber mounting long strip is like that.

  An optical fiber mounting long strip manufacturing method (initial claim 10) of the present invention is a method for manufacturing the optical fiber mounting long strip according to the above-mentioned initial claims 1 to 9, wherein the composite function is provided. When the body is formed, the optical fiber is set on the inner peripheral side and the long reaction body is set on the outer peripheral side.

  In such an optical fiber-mounted long strip (initial claim 1) of the present invention, a flexible support is adopted for the long support, and the sticking form is applied to such a long support. In addition, by mounting the optical fiber in the embedded form, it exhibits high deformability by taking advantage of the flexibility of the optical fiber, and it fits well with the outer surface shape of the mounting object like adhesive tape etc. If the long support is attached to the strain measurement object, the optical fiber is also attached together, so that the attachment is easy.

  In addition, a long reaction body for applying tension to the optical fiber was introduced, and at that time, the long reaction body and the optical fiber were mutually restrained. , The difference in deformation state between the optical fiber element and the long reaction element set so as to accompany the conformal deformation of the long support to the outer shape of the mounting object, specifically, the optical fiber element Tension is applied to the optical fiber in accordance with the extent that is stretched more than the long reaction force body.

Moreover, since the optical fiber is stuck or embedded in the long support and is also restrained by the long reaction body, the tension is stabilized over a long period of time.
Therefore, according to the present invention, it is possible to realize an optical fiber-mounted long strip that can accurately measure both stretching deformation and compression deformation and that can be easily and inexpensively constructed.

Moreover, in the optical fiber mounting long strip of the present invention (initial claim 2), since the hard resin tape is adopted as the long support, it is mounted on the monitoring target portion (mounted body). Can be simply and neatly performed by sticking or winding using an adhesive or a pressure sensitive adhesive as necessary. In addition, the long support can also serve as a long reaction force. In this case, the above-described tension is applied regardless of the rigidity of the mounted body due to the hard compressibility due to the rigidity. Incidentally, even when a soft resin tape or the like having an elastic modulus of 50 kN / cm ² or less is used as a long support, this long body functions as a reaction force mediating means, and tension using the rigidity of the mounted body Can be granted.

  Furthermore, in the optical fiber mounting long strip (initial claim 3) of the present invention, by adopting a tape in which a plurality of glass fibers are arranged in an aligned form or a braided form as a long support, It can be attached simply by attaching or winding, and the glass fiber is made to work as a long reaction force, and the long support for mutual restraint coupling between the long reaction force and the optical fiber It can be done by combining with the body.

Moreover, in the optical fiber mounting long strip (initial claim 4) of the present invention, the glass fiber is adopted as the long reaction body, so that the long reaction body and the optical fiber strand are the same. As the material of the system has various properties such as elastic modulus and thermal expansion coefficient, further stability of the tension can be expected, and the measurement accuracy is improved.
Further, in the optical fiber-mounted long strip of the present invention (initial claim 5), the long support is also used as the long reaction body, thereby reducing the number of members and simplifying the structure. It becomes.

  Moreover, in the optical fiber mounting long strip (initial claim 6) of the present invention, mutual binding is easy by bonding the optical fiber and the long reaction body with an adhesive cured product. Can be done. Further, by not interposing a hard spacer between the optical fiber and the long reaction element, or by appropriately setting the thickness of the spacer, the curvature of the outer surface of the mounting object, etc. The tension applied to the optical fiber can be adjusted by matching the difference in deformation state between the line and the long reaction force body.

  Moreover, in the optical fiber mounting long strip (initial claim 7) of the present invention, the coupling points between the optical fiber and the long reaction body are dispersed in a stepping stone shape, thereby supporting the long strip. Even when local deformation exceeding the allowable elongation of the optical fiber is loaded on the body, the local deformation acts on the optical fiber in a form diluted to a long span corresponding to the coupling point interval. The optical fiber can avoid damage such as undesired plastic deformation and breakage.

  Moreover, in the optical fiber mounting long strip (initial claim 8) of the present invention, a separator member is interposed between the optical fiber and the long reaction member, so The non-bonded state is more reliably ensured regardless of the situation (such as being pressed in the longitudinal orthogonal direction).

  Moreover, in the optical fiber mounting long strip (initial claim 9) of the present invention, an extra length is added to the long reaction body so that the optical fiber strand is curled on the inner peripheral side, The center-to-center distance is more than the total thickness so that they are separated from each other, and the center-to-center distance is more than double that of direct contact. Can be granted. Therefore, tension can be applied to the optical fiber even if the long fiber optic long strip is mounted on the concave surface or flat surface, and if the long fiber optic strip is mounted on the convex surface, greater tension can be applied. It can be applied to an optical fiber.

  In addition, in the method for manufacturing an elongated optical fiber according to the present invention (initial claim 10), the composite functional body is formed in a curled state. In this state, the optical fiber is elongated inward. Since the reaction force comes to the outside, it is possible to manufacture an optical fiber-mounted elongated strip that generates tension in the optical fiber when the curl is released.

  As mentioned above, although the effect of this invention was described regarding strain distribution measurement, the optical fiber mounting elongate strip | belt body of this invention can be used suitably also for temperature distribution measurement as described at the beginning. That is, the extra length (sag) generated in the optical fiber due to thermal expansion or the like causes zigzag of the optical fiber, which is also inconvenient for temperature measurement, and the extra length is not generated by applying tension in the present invention. ,That's what it means.

  An embodiment of an optical fiber-mounted long strip according to the present invention will be described with reference to the drawings. 1A and 1B show the structure of an optical fiber, where FIG. 1A is a side view and FIG. 1B is an end view. Moreover, FIG.1 (c) shows the other structural example about an optical fiber strand, and is an end elevation. Furthermore, FIG.1 (d) and (e) show the structure of a elongate support body, (d) is a perspective view, (e) is X arrow sectional drawing. 1 (f) and 1 (g) show the structure of the elongated optical fiber mounting strip, (f) is a perspective view, and (g) is a cross-sectional view taken along arrow X. FIG.

The optical fiber mounting long strip 30 is obtained by mounting the optical fiber 10 on the long support 20 in a sticking form, and the long support 20 includes a plurality of glass fibers (long fibers). Is made of a tape 21 in which a hard resin is used as a binder and bonded in a flat string shape, and also serves as a long reaction force body.
First, the structure of the optical fiber 10 will be described, and then the long support 20 and finally the optical fiber mounting long strip 30 in which they are assembled will be described.

  The optical fiber 10 may be a general one used for an optical fiber sensor suitable for strain measurement or temperature measurement using BOTDR or the like. For example, an optical fiber glass bare wire having a diameter of 0.125 mm is coated with a soft plastic. And a double-coated structure having a diameter of 0.4 mm and further coated with a polyamide resin to a diameter of 0.9 mm (see FIGS. 1A and 1B), or an optical fiber having a diameter of 0.125 mm There are a single coating structure (see FIG. 1 (c)) having a diameter of 0.25 mm by coating with an ultraviolet curable resin, and a coating with a fluororesin. These coatings are different from the long support 20 in that they are axisymmetric and concentric with the optical fiber of the axial core. Such optical fiber strands 10 are all flexible, and are allowed to be bent if the radius of curvature is several tens of mm or more.

  A typical size of the hard resin tape 21 constituting the long support 20 (see FIGS. 1D and 1E) is about 0.05 to 0.5 mm in thickness in the Z direction and has a width in the Y direction. The length in the X direction is about 3 to 30 mm, but other lengths are possible. Since the hard resin tape 21 is also a long reaction force body, it is desirable that the hard resin tape 21 be sufficiently hard in the sense that the elastic modulus is high and the yield strength is also high, but in spite of this, the hard resin tape 21 conforms to the outer shape of the mounting target surface. It is also necessary to use a resin having a certain degree of flexibility, such as a polyimide resin, a polyamide resin, a polyurethane resin, etc., and the thickness is preferably about 0.05 to 1 mm. There is also a possibility.

  The optical fiber mounting long strip 30 (see FIGS. 1 (f) and (g)) is made by attaching the optical fiber strand 10 to one side of the long support 20 with a hard adhesive 31. For the hard adhesive 31, an adhesive that exhibits a certain degree of flexibility even when cured, such as an epoxy resin adhesive or an acrylic resin adhesive, is used. Due to the bonding of the adhesive by the cured product, the optical fiber 10 (one of the composite functional bodies) and the long support body 20 (also used as the long reaction force body and the other of the composite functional bodies) span the entire length. In addition to being in a mutually restraining relationship, the optical fiber 10 is deviated from the neutral surface 32 relating to bending deformation when the tape is bent in the longitudinal direction.

  About the optical fiber mounting elongate strip 30 of this embodiment, the use aspect and effect | action are demonstrated referring drawings. FIG. 1 (h) is a view in the direction of arrow Y of an example of a usage mode in which the optical fiber mounting long strip 30 is mounted on the convex surface of the strain measurement object 40.

In order to perform strain measurement of the strain measurement object 40 using the long fiber body 30 mounted on the optical fiber, first, the long support 20 is convex on the surface of the strain measurement object 40 (in this example, a convex surface). The optical fiber strand 10 is attached so as to face to the outside. At that time, it may be pasted with an adhesive or the like, or it may be simply wound and fixed, but it is fitted tightly and deformed to fit the mounting target surface shape.
Then, the radius of curvature R of the optical fiber 10 becomes larger than the radius of curvature Ro of the neutral plane 32, and the optical fiber 10 is extended by ((R-Ro) / Ro) to cope with the elongation strain. The generated tension is generated in the optical fiber 10.

  When measuring both compression / elongation deformations, the elongation strain to be applied in the initial state is generally about 0.2%, although it depends on the characteristics of the optical fiber 10, so that the strain and the strain measurement object Based on the curvature of 40, a preferable distance between the neutral plane 32 and the optical fiber 10 is calculated, and an optical fiber mounting long strip 30 having a specification substantially satisfying the distance is prepared, as described above. Attached to the strain measurement object 40.

Then, one end or both ends of the optical fiber 10 are connected to a strain detector (not shown) to measure the strain distribution (see Patent Documents 1 and 2). In addition to the detection of the extension deformation, this strain detection device can also detect a compression deformation that causes a strain in a direction to reduce the tension if the tension is previously applied to the optical fiber 10.
When the strain measurement object 40 is deformed and the curvature distribution of the surface on which the optical fiber mounting long strip 30 is mounted changes, the curvature distribution of the optical fiber mounting long strip 30 also changes accordingly, and accordingly the optical fiber is changed. The elongation strain ((R-Ro) / Ro) of each part of the strand 10 also changes. As a result, the deformation state of the strain measurement object 40 can be detected by a strain distribution along the optical fiber-mounted elongated strip 30.

  In this way, in the long strip 30 mounted on an optical fiber, the deformation state of the strain measuring object 40 can be detected by mounting on the convex surface of the strain measuring object 40, and the mounting is special for the mounting. No extra tools are required, and if attached, tension is applied to the optical fiber 10 without using a pulling jig or the like. Incidentally, typical examples of the strain measurement object 40 include, for example, a circular or arched wall surface such as a tunnel, a storage tank, a bridge, and a ceiling of a building. Although the above example shows an example in which the surface to be mounted is a convex surface for ease of explanation, it goes without saying that the present invention is not limited to the above embodiment.

The configuration of another embodiment of the optical fiber-mounted elongated strip of the present invention will be described with reference to the drawings. FIG. 2 shows some other structural examples of the optical fiber-mounted long strip 30, and (a) to (c) are cross-sectional views of the optical fiber-mounted long strip 30 taken along the arrow X, (d). (G) is Z arrow sectional drawing of the elongate support body 20. FIG.
It should be noted that, in the drawings, even if the specific shapes and the like are different, the same reference numerals are assigned to the same or corresponding roles or materials. The X, Y, and Z directions are the same as in FIG. These are the same in other drawings.

2A is a cross-sectional view taken along the arrow X, and is formed by laminating a thin soft resin tape 22 to a hard resin tape 21 from above the optical fiber 10.
In this case, the long support becomes both the hard resin tape 21 and the soft resin tape 22, and the optical fiber 10 is mounted in an embedded form. Since the long reaction force body is only the hard resin tape 21 and the soft resin tape 22 is a protective cover, the soft resin tape 22 has a low elastic modulus and yield strength so as not to cancel the reaction force of the hard resin tape 21 as much as possible. For example, a low polyester resin, rubber resin, or the like is used.

  An optical fiber mounting long strip 30 shown in a cross-sectional view in the direction of the arrow X in FIG. 2 (b) is a long thin reaction force body in place of the hard resin tape 21 instead of the hard resin tape 21. (The other of the composite function body), and this and the optical fiber 10 (one of the composite function body) are covered with a soft resin cable 27 in a parallel state and coupled. The soft resin cable 27 has a flat surface to which the strain measurement object 40 is attached, a hard resin thin rod 26 is embedded near the attachment surface, and the optical fiber 10 is embedded in the distance.

  2 (c) shows a cross-sectional view taken along the arrow X, and FIG. 2 (d) shows a cross-sectional view taken along the arrow Z. Adopted for the other of the composite functional body), a soft resin tape 22 embedded therein is used for the long support, and the optical fiber strand 10 is adhered to one surface with a hard adhesive 31. The glass fiber 23 has substantially the same thickness and the same degree of flexibility as the glass fiber of the optical fiber 10, and is arranged in a direction along the optical fiber 10. Specifically, it is parallel to the optical fiber 10.

2 (e) to 2 (g), each of the long supports 20 shown in the cross-sectional view in the direction of the arrow Z is obtained by increasing the number of the above-described glass fibers 23, and the length of FIG. 2 (e) is long. In the scale support 20, the glass fibers 23 are arranged in an aligned form. Specifically, they are embedded in the soft resin tape 22 in parallel at equal pitches.
2 (f) and 2 (g) is a long support 20 in which a plurality of glass fibers 23 embedded in a soft resin tape 22 are arranged in a braided form, of which FIG. 2 (f) In the long support 20, the glass fibers 23 are inclined with respect to the longitudinal direction of the soft resin tape 22, and in the long support 20 of FIG. Parallel or orthogonal.

  These various types of optical fiber-mounted elongated strips 30 apply appropriate tension during mounting according to the degree of bending of the strain measurement target 40, the usage environment, and the like, and the required outer shape of the mounting target. Appropriate ones such as ones that have deformability suitable for use and those that can withstand long-term use are selected and used. The usage and operation thereof are the same as those relating to the above-described embodiment, although repeated descriptions are omitted.

  Another embodiment of the optical fiber-mounted elongated strip 30 of the present invention will be described with reference to the drawings. FIG. 3 shows the structure, where (a) is a cross-sectional view taken along the arrow X, (b) is a partially enlarged view, (c) is a comparison view, and (d) is a view taken along the arrow Y.

  This optical fiber mounting long strip 30 (see FIG. 3A) is affixed to one side of the long support 20 with a hard adhesive 31 with a hard adhesive 31 as in FIG. However, the contents of the long support 20 have been modified. Specifically, the long support 20 includes not only the hard resin tape 21 but also the soft resin tape 22 and the hard resin spacer 24, and the soft resin tape 22 is a strain measurement object 40 of the hard resin tape 21. The hard resin spacer 24 is attached to the mounting surface side of the optical fiber 10 of the hard resin tape 21. The optical fiber 10 is stuck on the hard resin spacer 24.

In the above example, a hard adhesive (elastic modulus> 70 to 80 kN / cm ² guideline) is used as an adhesive so that the displacement (such as “displacement”) in the adhesive layer does not increase. Epoxy adhesives etc. (elastic adhesives) are also soft (elastic modulus <50 kN / cm ² guideline) and have a large displacement but a reversible displacement, so that the displacement remains quantitatively and analyzable. Is useful.

  The hard resin spacer 24 is only required to be hard, and does not have to be as hard as the hard resin tape 21 that is a long reaction force. For example, a polyester resin, a vinyl chloride resin, or the like is used. The thickness A of the hard resin spacer 24 (see FIG. 3B) is for increasing the center-to-center distance B between the optical fiber 10 and the hard resin tape 21 to a desired value. The center-to-center distance B is increased by the thickness A of the spacer 24 rather than the total thickness C of the optical fiber 10 and the hard resin tape 21 when the hard resin spacer 24 is not present (see FIG. 3C).

  Moreover, in this optical fiber mounting long strip 30 (refer FIG.3 (d)), the adhesion fixation of the optical fiber strand 10 to the long support body 20 by the hard adhesive 31 is made | formed by the fixed pitch of 1000 mm, for example. Yes. The length of the bonded portion in the hard adhesive 31 is, for example, 10 mm, which is narrower than the unbonded portion sandwiched between them. Such a bonding location with the hard adhesive 31 is a connection point 33 that is continuous in a stepping stone shape.

The use mode and operation of the optical fiber mounting long strip 30 of this embodiment will be described.
In this case, the distance between the neutral plane and the optical fiber 10 is increased as the center-to-center distance B is increased. Therefore, if the curvature of the strain measurement object 40 is the same, the tension applied at the time of mounting increases. . Therefore, by appropriately selecting the thickness A of the spacer 24, it is possible to easily use the appropriate optical fiber-equipped elongated strip 30 for various types of strain measurement objects 40.
Further, since the optical fiber 10 is not restrained by the long support 20 in the unbonded portion between the coupling points 33 and 33, even when the long support 20 is excessively deformed, the excessive deformation is coupled. As long as it stays in a region narrower than the distance between the points 33 and 33, the optical fiber 10 can avoid unwanted plastic deformation and damage.

  The configuration of another embodiment of the optical fiber-mounted elongated strip 30 of the present invention will be described with reference to the drawings. 4A and 4B show the cross-sectional structure, where FIG. 4A is a cross-sectional view taken along the arrow Y, and FIG.

  Also in this case, the bonding between the optical fiber 10 and the long support 20 is performed by connecting the bonding points 33 by the hard adhesive 31 like a stepping stone. The state part is formed by covering the optical fiber 10 with a cylindrical separator 34 and preventing the separator 34 from adhering the optical fiber 10 and the hard adhesive 31. Thereby, since the hard adhesive 31 can be applied to the entire surface, the soft resin tape 22 is attached to the hard resin tape 21 from above the optical fiber element 10 to protect the optical fiber element 10. ing. In this case, both the advantage of the stepping stone combination and the advantage of the buried form are enjoyed.

  Other embodiments of the optical fiber-mounted elongated strip and the manufacturing method thereof according to the present invention will be described with reference to the drawings. FIG. 5A is a schematic view showing a method for manufacturing the optical fiber mounting long strip 30. 5 (b) to 5 (c) are cross-sectional views taken along the arrow Y of the optical fiber mounting long strip 30, (b) is a free state, and (c) is a flat surface mounted. d) shows the part mounted on the convex surface.

  The optical fiber mounting long strip manufacturing apparatus 50 (see FIG. 5A) feeds the optical fiber 10, the hard resin spacer 24 and the hard resin tape 21 from the three tape supply rollers to the roller 51. These are stacked by a roller 51 and rollers 52 and 53 that roll in contact with the roller 51 to form an optical fiber-mounted elongated strip 30 that is wound around a storage roller. The roller 51 is for attaching a curl with the optical fiber strand 10 on the inner peripheral side and the hard resin tape 21 on the outer peripheral side. The upstream roller 52 sandwiches each heated tape with the roller 51. The roller 53 on the downstream side is used for cooling and fixing the shape and properties of the optical fiber mounting long strip 30 which is laminated and curled on the outer peripheral surface of the roller 51.

  An optical fiber mounting long strip 30 that is mass-produced by such a manufacturing apparatus 50 has a composite functional body of the optical fiber strand 10 and the hard resin tape 21 with the optical fiber strand 10 on the inner peripheral side. Since the hard resin tape 21 which is a reaction force is formed on the outer peripheral side, in a free state where no external force is applied (see FIG. 5 (b)), the optical fiber strand 10 is curled with the inner peripheral side. To do. Further, since the hard resin spacer 24 having a thickness A is interposed between the optical fiber 10 and the hard resin tape 21, the center-to-center distance B between the optical fiber 10 and the hard resin tape 21 is the same. It is larger than the total thickness C (= 2 × (BA)).

Then, both conditions are combined, and the normal length obtained by adding an extra length to the normal length of the optical fiber 10 is charged to the hard resin tape 21 which is a long reaction force body.
For this reason (see FIG. 5C), when the optical fiber-mounted elongated strip 30 is mounted on the flat surface of the strain measurement object 40, the optical fiber-mounted elongated strip 30 is straightened with the curl being released. At that time, the optical fiber strand 10 extends more than the hard resin tape 21 by the extra length that has been charged, and a corresponding tension is applied to the optical fiber strand 10.

In this way, in the optical fiber mounting long strip 30, not only the convex surface of the strain measurement object 40 but also a flat surface can be easily mounted without using tools or jigs. As a result, an appropriate tension is naturally applied to the optical fiber 10. Typical examples of the flat strain measurement object 40 include a trolley wire used for power supply such as a train, various pipes, a large structure such as a tunnel and a building.
Further, if it is attached to the convex surface of the strain measurement object 40 (see FIG. 5 (d)), then it is assumed that the bending is performed in the direction opposite to the free state, but the tension applied to the optical fiber 10 is as follows. It will be further strengthened.

  Other embodiments of the optical fiber-mounted elongated strip 30 and the method for manufacturing the same according to the present invention will be described with reference to the drawings. 6A is a cross-sectional view taken along the arrow Y of the optical fiber-mounted elongated strip 30. FIG. (E) is a cross-sectional view taken along the arrow Y when the optical fiber mounting long strip 30 is mounted on the flat surface of the strain measuring object 40, and (f) is a strain measuring object of the optical fiber mounting long strip 30. It is Y arrow sectional drawing of the place with which it attached to 40 convex surfaces.

  This long optical fiber mounting strip 30 (see FIG. 6 (a)) has a protective cover and a soft resin tape 22 as a long support on the inner peripheral side, and the optical fiber strand 10 is placed on the outer peripheral surface. In this case, the two are partially bonded to each other with the hard adhesive 31, and here, the connection points 33 are arranged at a constant pitch and are connected in a stepping stone shape. Next (see FIG. 6B), the optical fiber strand 10 is left open, and hard resin spacers 24 that are thicker than the optical fiber strand 10 are run side by side on both sides thereof. Is attached to the outer peripheral surface of the soft resin tape 22. Then (see FIG. 6C), a wide hard resin tape 21 is overlapped on the outer peripheral surface of the hard resin spacer 24 and bonded together.

  In the optical fiber mounting long strip 30 thus formed (see FIG. 6 (d)), the upper and lower soft resin tapes 22 and the hard resin tape 21 and the hard resin on both sides between the coupling points 33 and 33 are provided. A free space 25 surrounded by the spacers 24 is secured. In a free state where no external force is applied, the long optical fiber mounting strip 30 is curled with the soft resin tape 22 on the inner peripheral side, and the optical fiber 10 is placed on the outer peripheral surface of the soft resin tape 22 in the free space 25. It is curved along the arc.

  Then (see FIG. 6 (e)), when such an optical fiber-mounted elongated strip 30 is mounted on the flat surface of the strain measurement object 40, the optical fiber-mounted elongated strip 30 is also uncurled. As a result, the optical fiber 10 extends more than the hard resin tape 21 by the excess length, and a corresponding tension is applied to the optical fiber 10. This point is the same as that of FIG. 5 described above, but the situation is different when it is attached to the convex surface of the strain measurement object 40.

  That is, (see FIG. 6F), when the optical fiber mounting long strip 30 is mounted on the convex surface of the strain measurement object 40 with the hard resin tape 21 on the inner peripheral side, the outermost soft resin tape 22 further extends. However, in the optical fiber 10 that has been biased toward the soft resin tape 22 in the free space 25, the portion fixed at the coupling point 33 remains on the soft resin tape 22 side, but the portion in between is the free space 25. It is displaced to the hard resin tape 21 side. Then, the elongation strain of the optical fiber 10 and the tension based thereon do not change so much regardless of whether the mounting target surface of the strain measurement object 40 is a flat surface, a convex surface, or the curvature of the convex surface is different. .

  Therefore, the optical fiber mounting long strip 30 in which the optical fiber 10 is biased and stored in the free space 25 may be a convex surface or a flat surface if the outer surface shape of the strain measurement object 40 is not concave. Can be easily mounted without using tools or jigs, and as a result, an appropriate tension is naturally applied to the optical fiber 10.

  As described above, the optical fiber mounting elongated strip of the present invention can apply tension to the optical fiber simply by mounting on the mounted body, but external tension applying means is appropriately used as necessary. There is no problem with doing it.

1 shows the structure and laying state of an optical fiber mounting elongated strip according to an embodiment of the present invention, where (a) is a side view of an optical fiber, (b) is an end view thereof, and (c) is another light. (D) is a perspective view of a long support, (e) is a cross-sectional view of the long support taken along the arrow X, (f) is a perspective view of a long strip mounted with an optical fiber, g) is a cross-sectional view taken along the arrow X, and (h) is a view taken along the arrow Y when the optical fiber-mounted elongated strip is mounted on the convex surface of the strain measurement object. About some other embodiment of this invention, (a)-(c) is X arrow sectional drawing of an elongate optical fiber mounting elongate body, (d)-(g) is Z arrow view of a elongate support body. It is sectional drawing. About other embodiment of this invention, the structure of an optical fiber mounting elongate strip is shown, (a) is X arrow sectional drawing, (b) is a partially expanded view, (c) is a contrast figure, (d) Is a view on arrow Y. About other embodiment of this invention, the structure of an optical fiber mounting elongate strip is shown, (a) is Y arrow sectional drawing, (b) is the one part enlarged view. (A) is a schematic diagram which shows the manufacturing method of an optical fiber mounting elongate strip, (b) is Y arrow sectional drawing of an optical fiber mounting elongate strip, (c) is other embodiment of this invention. A cross-sectional view taken along the arrow Y of the optical fiber mounting long strip mounted on the flat surface of the strain measurement object. FIG. 6D shows the Y of the optical fiber mounting long strip mounted on the convex surface of the strain measurement target. It is arrow sectional drawing. About other embodiment of this invention, (a)-(c) is a Y arrow line view which shows the manufacturing process of an optical fiber mounting elongate body, (d) is a Y arrow cross section of an optical fiber mounting elongate body. Fig. 8 (e) is a cross-sectional view taken along the arrow Y of the optical fiber mounting long strip mounted on the flat surface of the strain measurement object. (F) is the convex surface of the strain measuring object. It is Y arrow sectional drawing of the place where it attached to.

Explanation of symbols

10 Optical fiber (one of the composite functional bodies)
20 Long support 21 Hard resin tape (sufficiently hard, reaction force, composite functional body)
22 Soft resin tape 23 Glass fiber (sufficiently hard, reaction force, composite functional body)
24 Hard resin spacer (hard once)
25 Free space (uncoupled part)
26 Rigid resin thin rod (sufficiently hard, reaction force, composite functional body)
27 Soft resin cable 30 Long strip mounted with optical fiber 31 Hard adhesive (hardened material, bonding means)
32 Neutral surface 33 Connection point (stepping stone-like series of points)
34 Separator (non-bonded state forming member)
40 Strain measurement object (attachment object)
50 Optical fiber mounting long strip manufacturing equipment 51 Roller (Composite tool, curl forming member)
52, 53 Roller (heating side, cooling side)

Claims (10)

An optical fiber-mounted elongated strip that is used as an optical fiber sensor in which an optical fiber is mounted on a flexible long support in an attached or embedded form, and the optical fiber is It is mounted in the form of a composite functional body in which a strand and a long reaction body for applying tension to the strand are combined in a mutually constrained relationship. In the state where the optical fiber is disposed and freed from an external force, the optical fiber is not subjected to any tension or is not suitable for use as an optical fiber sensor. When the optical fiber sensor is attached to a measurement object surface having a different shape and deformed, a tension suitable for use as an optical fiber sensor is added to the optical fiber strand. . An optical fiber mounting long strip used as an optical fiber sensor in which an optical fiber is mounted on a flexible long support in an attached form or in an embedded form, and the optical fiber is The optical fiber , which is mounted in the form of a composite functional body in which the strands and a long reaction body for applying tension to the strands are coupled in a mutually restrictive relationship, and constitutes the composite functional body Between the strand and the long reaction body, a center-to-center distance having a dimension equal to or greater than the total thickness of both is provided, and the optical fiber element is disposed toward the long reaction body. Since the normal length obtained by adding an extra length to the normal length of the wire is set, this optical fiber-mounted long strip is free from external force so that the optical fiber strand side is located on the inner circumference. When it is curled in the form of the side and stretched straight, there is no tension on the optical fiber Has become what is pressurized, the optical fiber mounting elongated strip body, characterized in that. The optical fiber-mounted long strip according to claim 1 or 2, wherein the flexible long support is a hard resin tape. Elongated support of the flexible is a tape arranged in the glass fiber in the alignment mode or braided form of plural rows, the optical fiber mounting length according to claim 1 or claim 2, characterized in that Shakujo body. The long reaction body is a single or multiple glass fiber disposed in a direction along the optical fiber, and is described in any one of claims 1 to 4 . Long strip with optical fiber. The optical fiber-mounted long strip according to any one of claims 1 to 5 , wherein the flexible long support body also serves as the long reaction force body. In the composite functional body, the optical fiber and the long reaction body are bonded to each other in a form in which both are directly facing each other or a hard spacer is interposed therebetween. The long optical fiber-mounting elongated member according to any one of claims 1 to 6 , wherein the elongated member is formed of a cured product. The combination of the optical fiber and the long reaction body in the composite functional body is performed by connecting the connection points in a stepping stone shape, and the portion sandwiched between the connection points is in an unbonded state. The long optical fiber-mounting strip according to any one of claims 1 to 7 , wherein 9. The optical fiber according to claim 8 , wherein, in the uncoupled state, a separator member is interposed between the optical fiber and the long reaction body. Mounted long strip.   An optical fiber mounting long strip manufacturing method for manufacturing the optical fiber mounting long strip according to any one of claims 1 to 9, wherein the length of the optical fiber is set to the inner peripheral side. An optical fiber-mounted long strip manufacturing method, wherein the composite functional body is formed with a scale reaction force body on the outer peripheral side.

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