JP2010127824A - Fiber support device for fiber sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fiber support device for an improved fiber sensor enabling fixing force adjustment, disassembling and reassembling of a fiber so as to be superior in assembling by being simply detached. <P>SOLUTION: The fiber support device includes: a support body 1 having a through-hole 1a for passing a protection tube 9 of a fiber sensor F, an outer peripheral male screw part 10, and an edge widened inner peripheral face 12; a fluorocarbon resin ferrule 2 having a pair of support holes 15 passing a fiber wire 6, an edge narrowed outer peripheral face 16, a small diameter cylinder part 17, and a ring-like side peripheral face 18; and a union nut 3 having a female screw part 19 screwed with the male screw part 10, a ring-like push peripheral face 20 contacted on the ring-like side peripheral face 18, and a guide inner peripheral face 21 inserting the small diameter cylinder part 17. The fiber support device A grasps the fiber wire 6 passed through the support hole 15 by axial center direction push of the ferrule 2 due to tightening of the union nut 3 while the male screw part 10 is screwed with the female screw part 19 by fitting the edge narrowed outer peripheral face 16 to the edge widened inner peripheral face 12, and contacting the ring-like push peripheral face 20 on the ring-like side peripheral face 18. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a device for supporting a fiber sensor such as an optical fiber type liquid level sensor using the fiber portion thereof, that is, a fiber support device for a fiber sensor.

  As this type of prior art, those disclosed in Patent Document 1 and Patent Document 2 are known. The thing of patent document 1 is related with the manufacturing method of the ferrule of an optical fiber. That is, the ferrule cylinder 3 having the fiber insertion hole 2 in the center portion is divided into the divided bodies 3A and 3B in which the fiber insertion hole 2 is divided in the length direction, and the divided bodies 3A and 3B are brought into contact with each other. To form. The split bodies 3A and 3B are integrally molded by a molding die 5 in which convex ridge portions 4 that form the concave ridge portions 2A and 2B that form part of the fiber insertion hole 2 are formed on the cavity wall surface of the molding die. The ferrule tube body 3 in which the fiber insertion hole 2 is formed by abutting each of the divided bodies 3A and 3B and the concave portions 2A and 2B being attached to each other can be fixed by being fitted and attached by insert molding. .

  Further, in Patent Document 2, two ferrules are externally fitted and arranged on an optical fiber at a required distance, and a tubular joint is provided so as to cover a gap between the two ferrules. This is an optical fixed attenuator that is externally fitted to a portion and compressed while heating an optical fiber between two ferrules to form a compression bent portion. It can be incorporated into small components, and the optical fiber can be compressed while heated to form a compression bend.

  In the means according to Patent Document 1, by inserting a pair of divided bodies 3A and 3B into the cylindrical resin outer layer portion 10, the divided bodies 3A and 3B are regulated so as not to move away from each other, and between the two 3A and 3B. In this structure, the optical fiber line 6 is clamped and fixed. However, with this fixing means, the holding force of the optical fiber line 6 is structurally determined. Therefore, if not designed well, the holding force is too strong or too weak, and the holding force cannot be adjusted. There is a disadvantage that it is not possible to adjust the pinching force with the actual product or to retighten (compensation for pinching force) over time.

Next, in the means according to Patent Document 2, the optical fiber 50 is inserted into the small hole 7 of the ferrule 1, but it is finally fixed by the adhesive 10. Therefore, once fixed, it cannot be disassembled for maintenance or the like, and the optical fiber cannot be replaced over time, and there are difficulties in maintainability and practicality. As described above, in any of the patent documents, there remains room for improvement in terms of ease of assembly, disassembly and reassembly, and adjustment of the fixing force.
Japanese Patent Application Laid-Open No. 8-122565 JP-A-5-2110

  In view of the above circumstances, the object of the present invention has been improved so that the fixing force of the fiber can be adjusted, disassembled, and reassembled, and can be easily assembled with excellent assemblability. The object is to provide a fiber support device for a fiber sensor.

According to the first aspect of the present invention, in the fiber support device for a fiber sensor, the tip of the sensor unit 7, one or a plurality of fiber wires 6 drawn from the sensor unit 7, the sensor unit 7, and the fiber line 6 A fiber sensor F having a protective tube 9 covering the sensor side end, an insertion hole 1a through which the protective tube 9 can be inserted, a male threaded portion 10 on the outer periphery, and a forward expansion which is an opening of the insertion hole 1a. A support body 1 having an inner peripheral surface 12;
One or a plurality of support holes 15 into which the fiber line 6 can be fitted, a tapered outer peripheral surface 16 that can be fitted into the widened inner peripheral surface 12, and the taper in the direction of the axis X of the support hole 15. A small-diameter cylindrical portion 17 formed at the end opposite to the outer peripheral surface 16 and a surface intersecting the axis X at the boundary between the inner peripheral portion of the tapered outer peripheral surface 16 and the small-diameter cylindrical portion 17. A ferrule 2 made of a flexible material with an annular side peripheral surface 18 formed;
A union nut including a female screw part 19 that can be screwed into the male screw part 10, an annular pressing peripheral surface 20 that can contact the annular side peripheral surface 18, and a guide inner peripheral surface 21 that can be inserted through the small-diameter cylindrical part 17. 3 and
The tapered outer peripheral surface 16 is fitted into the forward expanded inner peripheral surface 12, the annular pressing peripheral surface 20 is in contact with the annular side peripheral surface 18, and the male screw portion 10 is in contact with the female screw portion 19. The one or more fiber wires 6 passed through the support hole 15 can be gripped by pressing the ferrule 2 in the axial direction by tightening the union nut 3 in the screwed state. It is characterized by.

  According to a second aspect of the present invention, in the fiber support device for a fiber sensor according to the first aspect, the guide inner peripheral surface 21 has a diameter as it approaches the end of the union nut 3 in the axis P direction. It is characterized by being formed on the expanding inner peripheral surface.

  According to a third aspect of the present invention, in the fiber support device for a fiber sensor according to the first or second aspect, the length d in the axial center X direction of the small diameter cylindrical portion 17 is the axis of the guide inner peripheral surface 21. The length is set to be equal to or less than the length D in the direction of the heart P.

  The invention according to claim 4 is the fiber support device for a fiber sensor according to any one of claims 1 to 3, wherein the ferrule 2 is made of a fluororesin.

  According to the first aspect of the present invention, as will be described in detail in the section of the embodiment, when the ferrule is pressed against the support body in the axial direction by the screwing of the union nut, it bites into the forwardly expanding inner peripheral surface. The tapered outer surface is pushed and the ferrule is contracted and deformed in the radial direction, whereby the support hole is also contracted and the fiber wire can be pressed radially inward to be firmly gripped. That is, the fiber wire can be held and fixed by the union nut tightening operation, and the fiber sensor can be supported, and the fiber wire can be released and released by the union nut loosening operation. Further, the fiber fixing force can be changed and set by adjusting the amount of diameter reduction of the ferrule according to the tightening amount of the union nut. As a result, it is possible to provide an improved fiber support device for a fiber sensor so that the fixing force of the fiber can be adjusted, disassembled, and reassembled, and can be easily assembled with excellent assemblability. be able to. In addition, the presence of the small-diameter cylindrical portion has an advantage that the fiber wire can be prevented from being bent suddenly at the portion coming out of the ferrule, and the life of the fiber wire can be expected to be extended.

  According to the invention of claim 2, although described in detail in the section of the embodiment, the structure in which the inner peripheral surface of the guide is widened forward and the small-diameter cylindrical portion can swing and move, Advantages in which fiber fibers and small diameter cylinders are less likely to be subjected to excessive force, preventing sudden bending of the fiber wire at the point coming out of the ferrule, and further prolonging the life of the fiber wire There is.

  According to the invention of claim 3, since the small-diameter cylindrical portion is smaller than the axial center width of the guide inner peripheral surface and does not protrude from the outer end of the union nut, the small-diameter cylindrical portion is damaged due to collision with other objects. There is an effect that the above-described guide guide action, that is, the life extension of the fiber line can be exhibited while preventing the fear.

  According to the fourth aspect of the present invention, an effect is obtained in which the ferrule is made of a fluororesin, and the fiber wire can be firmly held and fixed while exhibiting excellent properties in chemical resistance and high temperature resistance.

  Embodiments of a fiber support device for a fiber sensor according to the present invention will be described below with reference to the drawings. 1 and 2 are a side view and a cross-sectional view of the mounting tool, respectively, FIG. 3 is a cross-sectional view and a rear view of the ferrule, and FIG. 4 is a cross-sectional view showing a state in which the fiber sensor is fixedly supported on the mounting tool. FIG. 7 is a sectional view of the wearing tool according to the second embodiment and a sectional view in use.

[Example 1]
A fiber support device for a fiber sensor (hereinafter simply referred to as “fiber support device”) A according to the first embodiment is configured in a mounting tool S that supports a fiber sensor. That is, as shown in FIGS. 1 and 2, the mounting tool S includes a support body 1, a first ferrule (an example of a ferrule) 2, a first union nut 3, a second ferrule 4, and a second union nut. 5 and a straight type (straight union).

  As shown in FIGS. 4 and 5, the fiber sensor F supported and fixed by the mounting tool S includes a contact 7 at the distal end, a sensor portion 8 at the distal end, and a pair (one or more) drawn from the sensor portion 8. An example), that is, two fiber wires 6 and 6 and a protective tube 9 that covers the sensor portion 8 and the sensor side end portions of the fiber wires 6 and 6 are configured. The protective tube 9 is made of a fluororesin such as PFA, for example, and the fiber line 6 may be coated with a fluororesin.

  The support body 1, the first ferrule 2, and the first union nut 3 constitute a fiber support device A that sandwiches and fixes a pair of fiber wires 6 and 6 of the fiber sensor F (see FIG. 5). The support body 1, the second ferrule 4, and the second union nut 5 constitute a tube support device B that holds and fixes the cover tube of the fiber sensor F (see FIG. 5). That is, in the fiber sensor F, as shown in FIG. 4, the protective tube 9 near the sensor unit 8 is gripped and fixed by the tube support device B, and the pair of fiber wires 6 and 6 are formed near the protective tube 9 by the fiber support device A. By being held and fixed, the mounting tool S can be fixedly supported.

  As shown in FIGS. 1, 2, and 4, the support body 1 includes an insertion hole 1 a through which the protective tube 9 of the fiber sensor F can be inserted, a first male screw portion 10 on the outer periphery, a second male screw portion 11, and an axis P. This is a fluororesin component comprising a square portion 14 located in the middle of the direction, a first forwardly expanding inner peripheral surface 12 and a second forwardly expanding inner peripheral surface 13 which are openings of the insertion hole 1a. The first and second flared inner peripheral surfaces 12 and 13 are both part of a conical surface in a cone centered on the axis P, and are tapered peripheral surfaces inclined with respect to the axis P.

  As shown in FIGS. 2 to 4, the first ferrule 2 is a pair (one or a plurality of examples) into which the fiber line 6 can be fitted, that is, two support holes 15, 15, and a first forwardly expanded inner peripheral surface 12. A tapered outer peripheral surface 16 that can be fitted into the outer peripheral surface, a small-diameter cylindrical portion 17 that is tapered in the axial center X direction of the support holes 15 and 15 and that is formed at the end opposite to the outer peripheral surface 16, and a tapered outer peripheral surface 16 is provided with an annular side peripheral surface 18 formed as a surface orthogonal to the axis X (an example of “intersection”) at the boundary between the inner back portion of the 16 and the small-diameter cylindrical portion 17 (of a flexible material). Example). The axis X of the support hole 15 is parallel to the axis P of the support body 1 in the assembled state (state shown in FIG. 4).

  As shown in FIGS. 1, 2, and 4, the first union nut 3 is in contact with a female screw portion 19 that can be screwed into the first male screw portion 10 of the support body 1 and an annular side peripheral surface 18 of the first ferrule 2. It is formed in a nut-like component having a possible annular pressing peripheral surface 20 and a guide inner peripheral surface 21 into which the small diameter cylindrical portion 17 of the first ferrule 2 can be inserted. The guide inner peripheral surface 21 is formed on a flared inner peripheral surface (tapered inner peripheral surface) in which the inner end diameter is substantially equal to the outer diameter of the small-diameter cylindrical portion 17 and the outer end diameter is larger than that. Has been. Further, the length D of the guide inner peripheral surface 21 in the axis P direction is set to be slightly longer than the length d of the small-diameter cylindrical portion 17 in the axis P direction.

  As shown in FIGS. 2 and 4, the second ferrule 4 has a single second support hole 22 in which the protective tube 9 can be fitted, and a second constriction in which the second ferrule 4 can be fitted into the second widened inner peripheral surface 13. A second outer peripheral surface 23, a second small-diameter cylindrical portion 24 formed at an end opposite to the second constricted outer peripheral surface 23 in the axis P direction, and an inner back portion of the second constricted outer peripheral surface 23; The second annular side peripheral surface 25 is formed as a surface orthogonal to the axis P at the boundary with the second small diameter cylindrical portion 24, and is formed of a flexible material (fluororesin, rubber, etc.).

  As shown in FIGS. 1, 2, and 4, the second union nut 5 includes a second female screw portion 26 that can be screwed into the second male screw portion 11 of the support body 1, and a second annular side peripheral surface of the second ferrule 4. 25 is formed as a nut-like component including a second annular pressing peripheral surface 27 that can abut on 25 and a second guide inner peripheral surface 28 through which the small diameter cylindrical portion 24 of the second ferrule 4 can be inserted. The length W of the second guide inner peripheral surface 28 in the axial center P direction is set to be slightly longer than the length w of the second small diameter cylindrical portion 24 in the axial center P direction. The second guide inner peripheral surface 28 has a flared inner peripheral surface (tapered inner peripheral surface) whose inner end diameter is substantially equal to the outer diameter of the second small-diameter cylindrical portion 24 and whose outer end diameter is larger than that. Surface).

  As shown in FIGS. 2 and 4, the fiber support device A has a tapered outer peripheral surface 16 that is widened and fitted into the inner peripheral surface 12, and the annular pressing peripheral surface 20 abuts on the annular side peripheral surface 18, and A total of two fibers passed through the support holes 15 and 15 by pressing the axial direction P of the first ferrule 2 by tightening the union nut 3 in a state where the male screw portion 10 is screwed to the female screw portion 19. The lines 6 and 6 can be gripped.

  That is, since each fiber line 6 is inserted into the support hole 15 with no gap or with a very small gap, the first ferrule 2 is pressed against the support body 1 in the direction of the axis P by the union nut 3 being screwed. As a result, the tapered outer peripheral surface 16 which tries to bite into the forward inner peripheral surface 12 is pushed and the first ferrule 2 is contracted and deformed in the radial direction, whereby the support holes 15 and 15 are also contracted. The fiber wire 6 is pressed radially inward to be firmly gripped. For example, if the first ferrule 2 is made of a rubber-based material (elastic material) such as fluororubber, the diameter-reducing deformation of the first ferrule 2 due to the tightening of the union nut 3 is promoted, and the aforementioned gripping action is further promoted. It is possible.

  As shown in FIGS. 2 and 4, the tube support device B includes a second tapered outer peripheral surface 23 fitted into the second forward expanded inner peripheral surface 13 and a second annular pressing peripheral surface 27 on the second annular side. By pressing the second ferrule 4 in the axial center P direction by the tightening of the second union nut 5 in contact with the peripheral surface 25 and the second male screw portion 11 being screwed into the second female screw portion 2, 2 The protection tube 9 passed through the support hole 22 can be gripped.

  Since the guide inner peripheral surface 21 surrounding the small-diameter cylindrical portion 17 capable of guiding and guiding the fiber wire 6 is formed on a tapered inner peripheral surface that increases in diameter toward the outer end, the small-diameter cylindrical portion 17 is a union nut. Thus, the heel can also move so as to swing around the peripheral edge portion 3e. Therefore, the first ferrule is in a preferable state in which an unreasonable force hardly acts on the fiber wire 6 or the small diameter cylindrical portion 17 by the movable configuration of the small diameter cylindrical portion 17 capable of relaxing the bending force acting on the fiber wire due to an external force or the like. The effect of prolonging the life by the function of preventing a sharp bend of the fiber line 6 at the position extending from 2 can be obtained.

  As shown in FIG. 4, the fiber sensor F is attached by the mounting tool S as shown in FIG. 4 by the gripping action of the fiber wires 6 and 6 by the fiber support device A and the gripping action of the protective tube 9 by the tube support device B. There is an advantage that it can be firmly supported and the possibility of dust and foreign matter entering the protective tube 9 is also eliminated. The small-diameter cylindrical portion 17 does not receive a pressing force in the axial center P direction by the first union nut 3, thereby non-shrinking in the radial direction, and hardly causes a gripping force of the fiber wire 6 passed through it. Therefore, relative sliding movement in the axial center X direction between the inner peripheral surface of the support hole 15 and the fiber wire 6 is possible, and the fiber wire 6 coming out of the first ferrule 2 is bent suddenly by an external force or the like. There is also an advantage that the effect of regulating the diameter by the small-diameter cylindrical portion 17 is smoothly and effectively exhibited without the expansion and contraction in the length direction of the fiber line 6.

  The first ferrule 2 has a large diameter cylindrical portion 29 having a large diameter and a width in the direction of the axis P, which is formed between the outer peripheral surface 16 and the small diameter cylindrical portion 17. The portion 29 receives a pressing force in the direction of the axis P due to the screwing of the union nut 3, but a radial force is not directly generated unlike the tapered outer peripheral surface 16. Accordingly, the gripping action of the fiber wire 6 due to the reduced diameter of the support hole 15 in the portion of the large diameter cylindrical portion 29 is weaker than the gripping action in the portion of the tapered outer peripheral surface 16 and the gripping action in the portion of the small diameter cylindrical portion 17. Therefore, the gripping action of the fiber wires 6 and 6 by the first ferrule 2 becomes stronger as it goes from the outer end to the inner depth, and the guide guide action and the strong suppression of the sudden bending of the fiber line are achieved. A balance with the supporting action is achieved. In addition, the small-diameter cylindrical portion 17 is configured to be smaller than the width of the guide inner peripheral surface 21 in the direction of the axis P and not protrude from the outer end of the union nut 3, and there is a possibility that the small-diameter cylindrical portion 17 may be damaged due to collision with other objects. There is also an effect that the above-mentioned guide guide action can be exhibited while avoiding it.

[Example 2]
As shown in FIGS. 6 and 7, the fiber support device A is configured in a mounting tool S including an attachment body 31 (an example of the support body 1) for supporting a fluid device (fluid device) such as a valve, a pump, and a pipe. It may be what is being done. That is, the mounting tool S according to the second embodiment is a tube screw type (tube screw type) having a mounting body 31, a first ferrule 2 and a first union nut 3 each having a tapered male screw portion 30 at one end. It is made up of things.

  The mounting main body 31 is the same as that of the first embodiment except that the second male screw portion 12 of the support main body 1 in the case of the first embodiment shown in FIG. The parts that are substantially the same as the support body 1, the part from the first male screw portion 10 to the end of the mounting body 31 and the fiber support device A are exactly the same as in the first embodiment, and show the same places and functions. Here, the same reference numerals as those in the first embodiment are attached and the description thereof is made.

  In the mounting tool S according to the second embodiment, the fiber sensor F is supported by the fiber wires 6 and 6 being held and fixed by the first ferrule 2, and the protective tube 9 is inserted through the mounting body 31. 31a (an example of the insertion hole 1a) is long guided in the direction of the axis P.

Side view of fiber support device (Example 1) Sectional drawing which shows the structure of the fiber support apparatus of FIG. Shows a single ferrule, (a) is a cross-sectional view, (b) is a front view Sectional drawing which shows the use condition of the fiber support apparatus of FIG. Perspective view showing fiber sensor Sectional drawing which shows the fiber support apparatus by Example 2 Sectional view in use state of fiber support device of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Support main body 1a Insertion hole 2 Ferrule 3 Union nut 6 One or some fiber wire 7 Sensor part 9 Protection tube 10 Male thread part 12 Widening inner peripheral surface 15 Support hole 16 Tapered outer peripheral surface 17 Small diameter cylindrical part 18 Annular side Peripheral surface 19 Female thread portion 20 Annular pressing peripheral surface 21 Guide inner peripheral surface D Length of guide inner peripheral surface in axial direction F Fiber sensor P Support shaft center X Ferrule shaft center d Small-diameter cylindrical portion shaft center direction length

Claims (4)

The protective tube of the fiber sensor comprising: a sensor part at a tip part; one or a plurality of fiber wires drawn from the sensor part; and a protective tube covering the sensor part and a sensor side end part of the fiber line. A support body including an insertion hole that can be inserted, a male screw portion on the outer periphery, and a flared inner peripheral surface that is an opening of the insertion hole;
One or a plurality of support holes into which the fiber line can be fitted, a tapered outer peripheral surface that can be fitted into the forward inner peripheral surface, and opposite to the tapered outer peripheral surface in the axial direction of the support hole Flexible with a small-diameter cylindrical portion formed at the end, and an annular side peripheral surface formed as a surface intersecting the axis at the boundary between the inner diameter portion of the tapered outer peripheral surface and the small-diameter cylindrical portion A ferrule made of a material having properties;
A female screw part that can be screwed to the male screw part, an annular pressing peripheral surface that can contact the annular side peripheral surface, and a union nut that includes a guide inner peripheral surface through which the small-diameter cylindrical part can be inserted,
In the state where the tapered outer peripheral surface is fitted into the forward expanded inner peripheral surface, the annular pressing peripheral surface is in contact with the annular peripheral surface, and the male screw portion is screwed to the female screw portion A fiber support device for a fiber sensor configured to be able to grip the one or more fiber wires passed through the support hole by pressing the ferrule in an axial direction by tightening the union nut.   2. The fiber support device for a fiber sensor according to claim 1, wherein the guide inner peripheral surface is formed on a pre-expanded inner peripheral surface whose diameter increases as it approaches the end of the union nut in the axial direction.   The fiber support device for a fiber sensor according to claim 1 or 2, wherein a length of the small-diameter cylindrical portion in the axial direction is set to be equal to or less than a length of the guide inner peripheral surface in the axial direction.   The fiber support device for a fiber sensor according to any one of claims 1 to 3, wherein the ferrule is made of a fluororesin.

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