JPH09267125A - Manufacture of pipe having minute hole - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method which in suitable to mass production of a pipe having a minute hole and to efficiently manufacture a ferrule used for a coupler of an optical fiber. SOLUTION: A material wire is passed through between rolling rolls at least one, and intermediately formed wire 2 is manufactured by forming the cross-sectional shape into the approximately half-sized shape of that of the pipe having the micropore, a pair of the intermediately formed wires 2, 2 are joined so that the virtual cut faces 3, 3 are opposed to each other so as to match grooves comprising a half of the micropore which is formed along the center of the virtual cut face 3 of the pipe having the minute hole and a pair of joined lines 4, 4 which are appeared on the outside are welded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a fine hole pipe, and more particularly to a method for manufacturing a fine hole pipe capable of efficiently producing a ferrule which is an important component of a coupler for connecting optical fibers. .

[0002]

2. Description of the Related Art A ferrule has a length of several mm, an outer diameter of about 1.25 to 2.5 mm, and a fine inner hole having an inner diameter of 0.125 mm (0.005 inch) along a central axis. It is a cylindrical body, and it is fixed by passing an optical fiber through this minute inner hole and incorporated into a coupler for connecting the optical fiber.

However, the length is several mm and the diameter is 0.125.
Since it is difficult to drill a mm hole with a drill, conventionally, in order to manufacture this ferrule, an aluminum-based ceramic material or a stainless material was drilled with a laser beam.

[0004]

However, when a fine hole having a diameter of about two hairs is punched by laser processing, since the length thereof is several mm, the working time becomes long and the working machine. The processing cost is also high due to the high cost.

Further, since the processing uses the melting of the work by the laser beam, the hole diameter is different between the entrance end surface and the exit end surface, and further post-processing is necessary to correct the swelling of the melted portion. .

In addition, there are various inconveniences such as variations in hole diameter due to changes in voltage, and a long time required for setting a work.

As a result, the ferrule manufactured by the conventional technique was extremely expensive as a mechanical part.

[0008] Therefore, it is an object of the present invention to propose a method for inexpensively manufacturing a fine hole pipe for manufacturing a ferrule with high accuracy and efficiency.

[0009]

In order to achieve the above-mentioned object, the invention according to claim 1 is to pass a metal material wire between rolling rollers at least once, and its cross-sectional shape is that of a substantially fine hole pipe. The intermediate forming wire is manufactured by forming into a semi-concave shape, and the grooves constituting the half of the fine holes formed along the center of the virtual cut surface of the fine hole pipe are aligned,
It is characterized in that a pair of intermediate molding lines are joined so that their virtual cutting planes face each other, and a pair of joining lines appearing on the outside thereof are welded.

Further, in the invention as set forth in claim 2, the metal material wire is passed at least once between the rolling rollers, and the cross-sectional shape thereof is molded into a half-cut shape of that of a substantially fine hole pipe to manufacture an intermediate molding wire. Then, the grooves forming the half of the fine holes formed along the center of the virtual cutting surface of the fine hole pipe are aligned, and the pair of intermediate molding lines are arranged so that the virtual cutting surfaces face each other. And a pair of linear joint portions appearing on the outside thereof are fixed with an adhesive.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 and 12 show the invention described in claim 1 so clearly that it can be understood at a glance.

That is, in FIG. 1, reference numeral 1 is a metal material wire,
Reference numeral 2 respectively indicates an intermediate forming line, and in the method of the present invention, for example, a metal material line 1 having a circular cross section is subjected to rolling to form an intermediate forming line 2 having a cross-sectional shape that is a half-cut shape of that of a substantially fine hole pipe.

Then, a pair of intermediate molding lines 2 and 2 are shown in FIG.
As shown in FIG. 2, the virtual cutting surfaces 3 and 3 are joined so as to face each other, and the pair of joining lines 4 and 4 appearing outside are welded by, for example, a laser welding machine 12.

Further, in the invention according to claim 2,
Linear joining portion 5 corresponding to the joining line 4 (see FIG. 19)
Is fixed with an adhesive.

The invention described in claim 1 will be described in more detail below. The illustrated embodiment shows a method for continuously producing a pipe having fine holes.

That is, in FIG. 2, reference numeral 6 indicates a supply drum. A coil-shaped metal material wire 1 such as a stainless steel wire wound around the supply drum 6 is drawn out in the direction of the arrow, and this is shown in FIG. It is supplied to the rolling mill 7.

The rolling mill 7 in the illustrated embodiment has, for example, first to sixth six rolling rollers R1 to R6, and each rolling roller Rn (n = 1 to 6) has one rolling roller Rn.
Composed of a pair of cemented carbide forming rollers, pressing the annular grooves or ridges formed on the outer periphery of each forming roller against the metal material wire 1 to transform the metal material wire 1 into an intermediate forming wire 2 in stages. To process.

That is, as shown in FIG. 4, the metal raw material wire 1 is slightly crushed by the first rolling process by the first rolling roller R1 to make its cross-sectional shape an ellipse, and as shown in FIG. It is further crushed by the second-stage rolling process by the rolling roller R2 to have a cross-section rice cake shape.

Similarly, as shown in FIG. 6, the third rolling roller R3 performs a third-stage rolling process to form a substantially semicircular section, and the fourth rolling roller R4 performs a third-stage rolling process to obtain a semicircular section.

Further, as shown in FIG. 8, by the fifth rolling process by the fifth rolling roller R5, a rectangular cross section is formed along the center line of the virtual cut surface 3 indicated by the chord (diameter) having a semicircular cross section. Form a groove.

Then, as shown in FIG. 9, a sixth round (final stage) rolling process by a sixth rolling roller 6 makes the groove having the rectangular cross section form a half circle forming a half of a fine hole for accommodating an optical fiber. While forming the groove, the intermediate cross-section of the intermediate forming wire 2 extending from the rolling roller of the sixth bullet is made into a substantially semi-vertical shape of the fine hole pipe to be manufactured.

In the illustrated embodiment, this intermediate molding line 2
The cross-sectional shape of is the cross-sectional shape of the fine-hole pipe vertically cut by a plane including the central axis of the fine-hole pipe.

However, according to the present invention, the cross-sectional shape of the intermediate forming wire 2 does not necessarily have to be a strict half-shape of the fine hole pipe, and for example, a pair of intermediate forming wires 2 and 2 to be joined later may be used. If one of the cross-sections is larger than the semi-perforated shape of the micro-hole pipe, the other is made smaller by that amount, and the inner hole and the outer peripheral surface of the resulting micro-hole pipe are concentric, and each dimension has a predetermined value. All you have to do is enter the value.

By the way, in the case of rolling a metal material wire with a plurality of rolling rollers, if each of the rolling rollers is independently driven, the metal material wire between one roller and another roller adjacent thereto is forcibly forced. A force may be applied in the direction of being pulled or buckled.

The volume feed amount of the metal material wire 1 in each rolling roller Rn is the rotation of the rolling roller to the cross-sectional area of the metal material wire 1 shown in FIGS. 4 to 8 when the radius of each rolling roller is the same. This is because the product is multiplied by the speed, but if the cross-sectional area of the metal material wire 1 is not the same, the volume feed amount is different.

In order to prevent this, for example, the sixth rolling roller R6 at the final stage is used as a working / driving roller, and the other rolling rollers R1 to R5 are working / idling rollers.

Therefore, at the first stage, when the lead-out end of the metal material wire 1 shown in FIG. 2 is engaged with the first rolling roller R1, the first rolling roller is manually moved, and then the respective rolling rollers are similarly moved. After manually moving the metal material wire through and pulling out the drawn end of the metal material wire into the sixth rolling roller at the final stage, the electric motor drives the rolling machine 7 using the sixth rolling roller R6 as a driving roller. .

In order to continuously manufacture the fine-hole pipe as described above, at least two rolling mills 7 having the above-mentioned constitutions are prepared, and as shown in FIG. Are drawn in such a positional relationship that they face each other.

Then, as shown in FIG. 11, the pair of intermediate molding lines 2 and 2 are passed between the pair of joining rollers 8 having a U-shaped groove formed on the outer periphery thereof, and the pair of intermediate molding lines 2 are formed. 2, the relative position in the width direction is set to a predetermined position, that is, the grooves having semicircular cross sections formed on the virtual cut surface 3 are joined to each other to form the circular fine holes 9 (see FIG. 12). It is specified and sent to the next welding process.

The intermediate molding lines 2 and 2 sent out from the above-mentioned joining rollers 8 and 8 in a state of being joined to each other are shown in FIG.
Is held by the holder rollers 11 of the welding machine shown in FIG.
Welding with 2 and 12 makes it possible to obtain a long pipe having fine holes 9. In other words, the use of the method of the invention ends.

When the joining lines 4 and 4 are locally welded by the laser welding machine as described above, the welded part shrinks when cooled and the joining parts of the intermediate forming lines 2 and 2 are joined more reliably. .

In order to manufacture a ferrule using the fine hole pipe manufactured as described above as a raw material, the fine hole pipe may be cut into a certain length.

Although the process of manufacturing a ferrule from the fine hole pipe manufactured by the method of the present invention is not the gist of the present invention, one example thereof will be briefly described below for reference.

That is, as shown in FIG. 13, the fine hole pipe 13 obtained after the welding process is passed between the groove of the work guide 14 and the pressing plate 15, and the tip of the fine hole pipe 13 is an actuator of the switch 16. At the timing of driving, the cutter 17 operated by the output signal from the switch 16 cuts the tip portion of the fine hole pipe by shearing.

As shown in FIG. 14, the cut pipe W is projected from the pressing plate 15 by the plunger of the solenoid 17 at the timing of generation of the output signal from the switch 16.

As shown in FIG. 15, the projected pipes W, W are conveyed downward along a guide 18 and sequentially loaded in a turret holder 19.

Then, the pipe W loaded in the turret holder 19 and constrained by being pressed by the presser spring 21,
W is introduced between the two cutters (grinders) 22 to correct the length of the pipe W precisely and deburr the sheared end face.

The intermediate forming wires 2 and 2 are welded (see FIG. 12).
If the outer peripheral surface of the pipe W is distorted or the swelling of the meat is caused by the reference (see), it may be corrected by a coreless grinder (not shown) or the like.

It should be noted that the method of the present invention is not limited to the above-described embodiments, but can be modified in various ways.

For example, as shown in FIG. 16, the intermediate molding line 2
Flat surfaces perpendicular to the virtual cutting surface 3 are formed at both ends of the. This flat portion is formed by shortening the chord of the semicircle, and is of course formed by rolling.

In the fine hole pipe 13 manufactured according to the modified embodiment shown in FIG. 16, even if the meat rises when the joining line 4 is welded, the rise occurs in the fine hole pipe 13.
Since it fits within the circumscribed circle of the cross-sectional shape, it is not necessary to correct the swelling due to welding when manufacturing the ferrule.

Another advantage is that when the ferrule is fitted in the inner bore of the coupler and fixed with an adhesive, a flow allowance of the adhesive can be secured.

FIG. 17 shows another modified embodiment of the invention described in claim 1. In this embodiment, both ends of the intermediate molding line 2 are cut diagonally so as to overhang when viewed from the virtual cutting plane 3. A groove having a V-shaped cross section is formed at the joint when the pair of intermediate molding wires 2 and 2 are joined.

Since the operation and effect of the embodiment shown in FIG. 17 are almost the same as those of the modified embodiment shown in FIG. 16 described above, further detailed description will be omitted.

FIG. 18 shows a further modified embodiment of the invention described in claim 1, in which the micropores 9 into which the optical fibers are inserted have a square cross-sectional shape.

In the ferrule manufactured from the micro-hole pipe according to this embodiment, the optical fiber inserted into the micro-hole 9 makes line contact at four points along the circumference thereof, so that the optical fiber is prevented from moving within the inner hole. In addition to being able to expect the original function of the ferrule, that is, grasping it, it is possible to further reduce friction, thereby providing another advantage that it is easy to insert an optical fiber into the ferrule.

In this embodiment, the corners of the V-shaped groove forming the half of the fine hole 9 formed on the virtual cut surface 3 do not necessarily have to have an edge, and may be slightly sloping. good. This is because the optical fiber does not touch the corner.

The cross-sectional shape of the groove formed on the virtual cut surface does not necessarily have to be V-shaped as shown in FIG. 8 and may be U-shaped (not shown).

FIG. 19 shows a cross-sectional shape of a micro-hole pipe manufactured according to an embodiment of the invention described in claim 2.
In the figure, reference numeral 23 indicates a joint.

The joint portion 5 is formed as a slit which is connected to each of a pair of hollow cylinders 24, 24 which are formed so as to be parallel to the minute holes 9 so as to sandwich them.

When the intermediate forming wires 2 and 2 formed by rolling as shown in FIG. 19 are joined, the linear joining portions 3 and 3 appearing on both sides are quickly dried from, for example, an adhesive injection pipe (not shown). The adhesive is injected and fixed (see FIG. 12).

Then, the adhesive flows into the joint portion 3 to firmly bond the intermediate molding lines 2 and 2. At this time, even if the adhesive contracts, the hollow tubes 24 and 2 that also serve as a reservoir of the adhesive.
It is prevented that both ends of the intermediate molding wire 2 to which elasticity is imparted by 4 are elastically deformed and an unreasonable force is applied to the joint.

[0053]

As is apparent from the above description, according to the present invention, it is possible to accurately manufacture a fine hole pipe by rolling and welding or bonding, and a ferrule can be obtained by cutting this, so that a conventional expensive method is used. It is possible to supply ferrules that were various parts at low cost.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the principle of the method of the present invention.

FIG. 2 is a diagram showing a first state of a metal material wire.

FIG. 3 is a diagram showing an example of the structure of a rolling mill, in which the intervals between rollers are shown to be constant for the sake of clarity.

FIG. 4 is a schematic cross-sectional view showing a first stage rolling process using a first rolling roller.

FIG. 5 is a schematic cross-sectional view showing a second stage rolling process using a second rolling roller.

FIG. 6 is a schematic cross-sectional view showing a third stage rolling process using a third rolling roller.

FIG. 7 is a schematic cross-sectional view showing a fourth stage rolling process using a fourth rolling roller.

FIG. 8 is a schematic cross-sectional view showing a fifth stage rolling process using a fifth rolling roller.

FIG. 9 is a diagrammatic cross-sectional view showing a final rolling process using a sixth rolling roller.

FIG. 10 is a diagram showing an example of a mode in which an intermediate forming line is taken out from a pair of sixth rolling rollers, in which fine holes are enlarged and shown for clarity.

FIG. 11 is a diagram showing a step of joining intermediate molding lines.

FIG. 12 is a diagram showing a welding process of an intermediate forming wire.

FIG. 13 is a diagram showing a step of cutting a fine hole pipe.

FIG. 14 is a diagram showing a projecting process of the cut fine hole pipe.

FIG. 15 is a diagram showing a grinding process of a cut fine hole pipe.

FIG. 16 is an enlarged cross-sectional view of a fine hole pipe showing a modified embodiment of the invention according to claim 1.

FIG. 17 is an enlarged cross-sectional view of a fine hole pipe showing another modified embodiment of the invention according to claim 1.

FIG. 18 is an enlarged sectional view of a fine hole pipe showing still another modified embodiment of the invention according to claim 1.

FIG. 19 is an enlarged cross-sectional view of a fine hole pipe for explaining the invention according to claim 2.

[Explanation of symbols]

 1 Metal material wire 2 Intermediate forming wire 3 Virtual cutting surface 4 Joining line 5 Joining part 7 Rolling machine 9 Micro hole 12 Laser welding machine 13 Micro hole pipe

Claims (2)

[Claims] 1. A metal material wire is passed between rolling rollers at least once, and its transverse cross-sectional shape is formed into a semi-vertical shape of that of a substantially fine hole pipe to produce an intermediate formed wire, and a virtual cut section of the fine hole pipe. The pair of intermediate molding lines are joined so that their virtual cutting planes face each other so that the grooves forming the half of the fine holes formed along the center of the A method for manufacturing a micro-hole pipe, which comprises welding the joining line of the pipe. 2. A metal material wire is passed between rolling rollers at least once, and its transverse cross-sectional shape is formed into a semi-vertical shape of that of a substantially fine-hole pipe to produce an intermediate formed wire. The pair of intermediate molding lines are joined so that their virtual cutting planes face each other so that the grooves forming the half of the fine holes formed along the center of the A method for producing a micro-hole pipe, characterized in that the linear joint portion of (1) is fixed with an adhesive.