JP4923294B2 - Mechanical splice - Google Patents

Description

  The present invention relates to a mechanical splice for connecting optical fibers.

  In response to the demand for optical fiber capable of high-speed and large-capacity transmission, the construction of medium- and long-distance trunk lines has been completed, and efforts to realize an optical wiring system in each home are being rapidly promoted. Yes.

  Here, fusion splicing with high reliability is often used for the connection of optical fibers, but it takes time to connect and reinforce after connection, the apparatus is expensive, and a power supply is required. There are problems.

  In order to solve this problem, an optical fiber such as Japanese Patent No. 3540096 and Japanese Patent No. 3725214 is fixed by performing axial alignment with a V-groove or the like, and a refractive index matching material at an optical fiber butt portion such as Japanese Patent Application Laid-Open No. 2004-264755. Mechanical splices have been proposed and marketed, which are designed to easily connect and prevent an increase in loss by devising storage.

  FIG. 3 is an external perspective view of a conventional mechanical splice intended for connecting an optical fiber having a core wire diameter of 0.25 mm. 4A to 4C are explanatory diagrams of the optical fiber connection method, and FIGS. 4D to 4F are cross-sectional views taken along lines AA, BB, and CC, respectively. .

    As shown in FIG. 3, the conventional mechanical splice 31 includes a V-groove 35 in which a V-groove 34 for aligning the cores 33a and 33b of the optical fibers 32a and 32b is formed, and the V-groove substrate 35. There are three divided pressing substrates 36a, 36b, 36c that are pressed and fixed from above, and a clamp spring 37 that holds and fixes the V-groove substrate 35 and the pressing substrate 36 from above and below.

    When the optical fibers 32a and 32b are connected to each other, the wedge 39 is inserted into the wedge insertion groove 38 between the V-groove substrate 35 and the pressing base 36 and spread (FIG. 4A), and a gap is generated. By inserting the optical fibers 32a and 32b from both ends of the mechanical splice and butting them together ((FIG. 4 (b)), the core wires 33a and 33b are attached to each other, and the wedge 39 is pulled out, thereby restoring force of the clamp spring 37, Positioning and gripping of the optical fibers 32a and 32b in the V-groove 34 are performed ((c) in FIG. 4).

Problems to be solved by the invention

However, the mechanical splice has the following problems to be solved.
First, since the substrate for holding the optical fiber is composed of the substrate 35 having the V-groove 34, the pressing substrates 36a, 36b, 36c divided into three parts, and the four-point substrate, the accuracy of the individual substrates is maintained. It is difficult and the number of parts is so large that parts management becomes cumbersome, which may increase manufacturing costs.

  Second, in order to create a gap necessary for connecting optical fibers, a wedge 39 is inserted into a slit 38 formed between the substrates 35 and 36, and optical fibers 32a and 32b are inserted from both ends. After the core wires are brought into contact with each other, a wedge 39 is pulled out in order to position and hold the optical fiber, so a dedicated tool is required.

  Thirdly, because of the structural limitation to insert the wedge, the clamp spring 37 that holds and fixes the substrate 35 having the V-groove 34 and the holding substrate 36 from above and below is held from the side, so that the optical fiber and the core. It is difficult to equalize the gripping force of the line.

  Fourthly, the substrate constituting the mechanical splice is composed of a resin-molded product with high mass productivity. Since the resin thermally expands or contracts due to a change in the temperature of the external environment to be used, there is a possibility that the gripping state of the optical fiber cannot be maintained properly.

  Fifth, the refractive index matching material 11 is filled in the vicinity of the butt portion of the optical fiber core wire for the purpose of reducing reflection, and a device for accommodating the refractive index matching material on the substrate has been devised. The structure is complicated and may increase the production cost.

Means for solving the problem

In order to achieve the above object, the mechanical splice of the present invention includes a substrate B having U-grooves for housing optical fiber coatings (both may be V-grooves) at both ends and a V-groove for storing optical fiber cores at the center, The optical fiber coating portion storage U-groove (may be a V-groove) at both ends and the substrate A having a recess for storing the refractive index matching material at the center.
Further, the grooves on both ends of the substrate B are inclined so that the optical fiber can be easily inserted.
The substrate A and the substrate B have a concave and convex coupling portion on the side wall of the central portion that accommodates the optical fiber core wire portion, and have a structure that prevents the refractive index matching material from being held and dust from entering.
The substrate A is made of a material having high bending strength and good elastic recovery.
The spring for gripping and fitting the substrate A and the substrate B is U-shaped and formed in a shape that bows upward (U-shaped) at the top, and the convex shape of the U-shaped spring end The portion is provided so as to bite into the concave groove of the substrate A.
As a work procedure, first, an optical fiber at one end is inserted, and when the coated portion of the optical fiber hits, the spring that has bite into the concave groove of the substrate A is pressed with a finger. As a result, the convex part of the U-shaped spring end is removed from the concave groove of the substrate A and bites into the concave groove of the substrate B, so that both the substrate A and the substrate B are securely grasped and fixed. The covering portion and the core wire are properly gripped and the position is fixed.
Next, after inserting the optical fiber core wire from which the coating of the end portion was similarly removed from the remaining side and confirming the butting of the optical fiber core wires, by pressing the U-shaped spring, The convex portion of the U-shaped spring that bites into the concave groove of the substrate A comes out and bites into the concave groove of the substrate B. As a result, the fixing of the remaining optical fiber covering portion and the core wire is completed.

    The present invention according to claim 1 is a mechanical splice for securely holding a core wire from which one optical fiber coating member has been removed at each end and securely connecting optical fibers inserted separately from both ends. A U-groove portion having a corrugated portion for accommodating the covering member on the extension line and a V-groove for accommodating and aligning the exposed core wire, having an inclination that facilitates insertion of each optical fiber, Consists of three points: two substrates (A and B) and a pressure member (pressing spring) that have a concave groove that absorbs the flow of the filled refractive index matching material and that can hold both the covering member and the core wire Therefore, it has a feature that it is economical because it has a simpler component structure than conventional products.

  According to the second aspect of the present invention, since the substrate A of the mechanical splice body is made of a material having high bending strength and good elastic recoverability, the optical fiber can be gripped by the temperature change of the external environment to be used. There is a feature that the possibility that the state cannot be properly maintained can be reduced.

  According to the third aspect of the present invention, the mechanical splice body is composed of two substrates, a substrate A and a substrate B, and has concave and convex coupling portions on both sides of the central portion that houses the optical fiber core portion. Because it has a structure that reliably connects even without a pressure member (pressing spring), it can be filled with a refractive index matching material without increasing the number of components. The deterioration of the transmission characteristics of the optical fiber connection portion can be reduced, and the reliability of the connection portion can be improved.

  According to the fourth aspect of the present invention, the spring, which is a pressure member for gripping and fitting the substrate A and the substrate B of the mechanical splice body, has a U-shape and has a bow shape (U-shape) at the top. Since it is molded in a warped form, it is possible to hold the gap between the substrate A and the substrate B necessary for insertion of the optical fiber and grip after connecting the optical fiber with the same member, without using a tool. In addition, there is a feature that one end can be connected and disconnected.

  The present invention according to claim 5 is provided in such a manner that the convex portion of the U-shaped spring end of the pressurizing member added to the mechanical splice body bites into the concave groove of the substrate A. Since both ends of the optical fiber are provided in a shape that bows upward (U-shaped), the optical fiber can be inserted without attaching or detaching a tool.

  According to the sixth aspect of the present invention, in the work stage, when the optical fiber is inserted at each end and the optical fiber coating portion or the optical fiber core wire abuts, it digs into the concave groove of the substrate A and warps like a bow. Hold the upper part of the U-shaped bracket with your finger. As a result, the convex portion of the U-shaped spring end is separated from the groove portion of the substrate A and bites into the concave groove of the substrate B, so that both end surfaces of the substrate A and the substrate B are securely in contact with each other. Since the covering portion is securely gripped and the optical fiber core wire is fixed at an accurate position, there is a feature that connection and disconnection can be performed one by one without using a tool.

  The means for solving the problems described above are described for facilitating the present invention, and each disclosed element includes all designs, improvements, changes, etc. belonging to the technical scope of the present invention. Shall be included.

The invention's effect

  As described above, according to the present invention, a core wire from which a single optical fiber covering member is removed can be easily inserted at each end, and can be securely gripped without using a tool, and an accurate position can be secured.

  In addition, when matching the optical fiber inserted from the other end, the optical fiber core wire can be reliably aligned, and the refractive index matching material can be used to prevent the transmission characteristics of the optical fiber connection portion from deteriorating. Considered in half.

  Furthermore, the mechanical splicing device of the present invention has a small number of parts and can reduce the manufacturing cost.

These are the perspective views which show the whole component which comprises the mechanical splice of this invention. Is a form in which the mechanical splice of the present invention is delivered to the installer. These are the external appearance perspective views of the conventional mechanical splice. (A)-(c) is explanatory drawing of the optical fiber connection method of the mechanical splice shown in FIG. 3, (d) is the sectional view on the AA line of (a), (e) is (b). BB sectional drawing, (f) shows CC sectional drawing of (c), respectively. These are the external appearance perspective views of the state in which the optical fiber of one end was hold | maintained with the mechanical splice of this invention. (A) is an external perspective view of the state in which the optical fibers at both ends are held by the mechanical splice of the present invention. In order to show the cross-sectional shape of the mechanical splice with the optical fibers connected, (b) II sectional view, (c) shows the II-II sectional view, respectively.

Explanation of symbols

1--Board A
2--Board B
12 --Coating member holding part 15 --Fitting part 16 with the recess 35 of the substrate A --Linking groove 18 with the pressure member 26 --Linking groove 19 with the pressure member 28 --Refractive index matching material Groove 20 that absorbs the flow component of the sheet--Pressure member 24 that has been molded in a U-shape--Convex portion 26 for pressurizing substrate A--Convex protrusion for concavity 16 of substrate A and concavity 36 of substrate B Part 27--Convex convex part 28 between concave part 17 of substrate A and concave part 37 of substrate B --Convex convex part 31a between concave part 18 of substrate A and concave part 38 of substrate B--For optical fiber insertion Inclined portion 31b--Inclined portion 32 for inserting an optical fiber--Optical fiber coating gripping U-groove 32a--Optical fiber 32b--Optical fiber 33--V-groove containing optical fiber core wire 33a--Optical fiber core wire 33b-- Optical fiber core wire 34 --Optical fiber covering grip convex part 35 --- Substrate B Fitting portion 36 of the convex portion 15 - coupling groove of the claw 26 of the pressure member 37 - binding groove of the claw 27 of the pressure member 38 - binding groove of the claw 28 of the pressure member

Claims (6)

A mechanical splice that securely grips the optical fiber from which one optical fiber coating member has been removed at each end and securely connects optical fibers inserted separately from both ends. A U-groove part having a corrugated shape portion and a V-groove for accommodating and aligning the exposed core wire, and a refraction for accommodating a flow of the filled refractive index matching material extending in the width direction along the V-groove A mechanical splice comprising two substrates (A and B) and a pressurizing member (pressing spring) that have a rate matching material relief groove and that can hold both the covering member and the core wire.
  The substrate B of the mechanical splice body is made of a material having high bending strength and good elastic recovery. The mechanical splice body is composed of two substrates, a substrate A and a substrate B. The mechanical splice body has concave and convex coupling portions on both sides of the central portion that accommodates the optical fiber core wire portion, and a pressure member (presser It has a structure that can be securely connected even in the absence of a spring.
The coupling portion can be filled with a refractive index matching material.   The spring, which is a pressure member for gripping and fitting the substrate A and the substrate B of the mechanical splice body, has a U-shape and is molded in a shape that bows upward (U-shape) at the top. It is characterized by.   The mechanical splice is provided in such a manner that the convex portion of the U-shaped spring end of the pressurizing member bites into the concave groove of the substrate A, and both ends of the substrate A are warped in a bow shape (U shape) at the top. It is provided in a rising form.   At the work stage, when an optical fiber is inserted at each end and the coated portion of the optical fiber or the optical fiber core wire hits, the upper part of the U-shaped bracket that digs into the concave groove of the substrate A and warps in the shape of a bow. Hold with your finger. As a result, the convex portion of the U-shaped spring end is separated from the groove portion of the substrate A and bites into the concave groove of the substrate B, so that the one end surfaces of the substrate A and the substrate B are securely in contact with each other. The covering portion is securely gripped, and the optical fiber core wire is fixed at an accurate position.

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