JPH01244412A - How to insert a linear object into a pipe - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for inserting a linear body into a tube, and particularly to a method for inserting a linear body into a tube using vibration.

The present invention is used to manufacture optical fiber cables, electric wires, composite structure pipes, and other products in which optical fibers, metal wires, and other linear bodies are inserted into protective tubes or sheaths. .

[Prior Art] There are cases where it is necessary to insert a linear body into a long tube or the like. For example, optical communication cables that have become widely used in recent years are required to have a metal-coated structure because optical fibers are weak in strength. For this purpose, it is necessary to insert the optical fiber core or coat into a steel pipe with a diameter of several millimeters or less and a length of several hundred meters or more. Alternatively, a metal wire such as a steel wire may be inserted into the tube as a mesh wire before the optical fiber is inserted.

2. Description of the Related Art Conventionally, methods for manufacturing a linear body wire by inserting a linear body into a tube such as a metal tube are known as disclosed in JP-A-58-181illO and JP-A-62-44010. In these methods, the carrier section H or tube through which the linear object is inserted is vibrated, a conveying force is applied to the linear object based on the principle of vibrating conhair, and the linear object is inserted into the carrier section or tube.

In these methods, at the beginning of the insertion of the linear body, the linear body is previously inserted into the entrance portion of the tube by a length sufficient to apply a sufficient conveying force to the linear body. This preliminary insertion can be performed manually or by mechanical means such as a pinge roller. Note that since the inlet end of the tube is fixed to the coil of the tube, it vibrates together with the coil.

[Problems to be Solved by the Invention] However, the conventional linear body insertion method has the following problems.

(a) Since the pawn entrance end is vibrating, the linear body is pawned [1
The portion in front of the end vibrates in a large undulating manner, and the centrifugal effect of this causes a force to be ejected to the outside of the tube, preventing it from entering the tube. For this reason, preliminary insertion is required at the beginning of insertion, which reduces work efficiency. If the pre-insertion length is short, a sufficient conveying force will not be applied to the linear body and the linear body will not enter the tube, so that it must be pre-inserted over a considerable length.

(b) The linear body is subjected to rippling bending before the fiber inlet end, which causes microcracks, especially in optical fibers. Furthermore, the linear body gets caught in the swinging movement and comes into contact with the tube end, causing damage.

Therefore, the present invention aims to provide a method for inserting a linear object into a tube, which is efficient and allows the linear object to be inserted into a tube without causing damage.

[Means for Solving the Problems] In the method of inserting a linear body into a pipe according to the present invention, first, the pipe is wound into a coil shape to form a coil of the pipe. The inlet portion of the tube is then formed away from the coil of tube, and the inlet end of the tube is fixedly supported in a stationary state. Then, while vibrating the coil of the tube so that any point on the tube reciprocates along a spiral path, the linear body is fed to the inlet end by a feeder placed near the inlet end of the tube at least at the initial stage of insertion. send to.

To form a coil of tubing, the tubing is wound around a cylindrical body such as a bobbin or spool. The diameter of the tube coil is 150 from the viewpoint of ease of insertion and not giving excessive bending stress to the linear body.
It is desirable that the thickness is +nm or more.

To vibrate the tube coil, the cylindrical body may be driven by a known means such as a vibration motor or an electromagnetic pie break. The vibration conditions are, for example, a vibration angle (i.e., helical lead angle) of 5 to 30 degrees, and a vibration frequency of 10 to 30 I (
z, the total amplitude is about 0.2 to 2.0 mm in the vertical component.

The inlet section also vibrates along with the coiled portion of the tube, but since the inlet end of the tube is stationary and fixed, a bending moment is applied to the inlet section. Therefore, in order to avoid excessive stress on the inlet section, this section must have a certain length and is preferably curved. Although it varies depending on the material of the tube, an appropriate length of the inlet portion is about 100 to 300 times the outer diameter of the tube, and a practical radius of curvature when curved is 50 to 200 times the outer diameter of the tube.

Further, from the viewpoint of arrangement of the device, it is desirable that the inlet portion be in a horizontal plane.

As the feeder for feeding the linear body to the entrance end of the tube, a vibrating feeder driven by electromagnetic force or air pressure, a roll feeder equipped with rotating rolls, etc. are used. The feeder is placed near the inlet end of the tube to such an extent that the linear body fed to the inlet end of the tube does not sag. A feeder feeds the wire into the inlet end of the tube while the wire is forced through the entire length of the tube. Alternatively, a conveyance force sufficient to cause the linear body to enter the pipe due to vibration (a force large enough to overcome the static inertia of the linear body upstream of the material inlet end, the frictional force between it and the guide, etc.) The feeder may be operated only until this occurs. In the former case, the vibration of the tube does not inhibit the insertion of the linear object after the steady insertion state is reached, that is, even if the feeding speed of the feeder does not match the insertion speed of the linear object due to the vibration of the tube. Use a feeder that does not cause excessive tensile force or sag on the linear body, such as a vibrating feeder. In the latter case, after the feeder is stopped, the linear body moves forward due to the vibration of the tube.

Therefore, when using a roll feeder (,,
Measures are taken such as releasing the drive of the roll to make it free, or bringing it out of contact with the linear body so as not to impede the advancement of the linear body. In order to send the linear body to the feeder, a forward force is applied to the linear body, for example, by rotating a reel around which the linear body is wound by a motor. The magnitude of this sending force is 1 minute to feed the linear body to the feeder, and the force of 6 J to push the linear body into the tube is not necessary.

When the coil of the tube is vibrated so as to reciprocate along a spiral path (any point on the working tube), the linear body inside the coiled tube moves diagonally upward and forward from the inner wall surface of the tube. Receive the opposing force i-J
Ru. Due to this force, the linear body jumps in the diagonal L direction within the tube or slides on the inner wall surface of the tube. In this way, the linear body within the tube is intermittently given a conveying force in the coil circumferential direction by the inner wall, and travels within the tube.

In addition, at the initial stage of insertion, the linear body is pushed into the tube part [21] by the feeder. Therefore, the above-mentioned backup procedure, which was conventionally performed, is not necessary.3.Embodiment A case will be described as an embodiment in which an optical fiber is inserted into a small diameter and long steel pipe.

First, an example of an apparatus for carrying out the insertion method of the present invention will be described. FIG. 1 is an overall view of an apparatus for carrying out the present invention, and FIG. 2 is a plan view of a vibration table which is a part of the apparatus.

The pedestal 11 is firmly fixed to the floor surface 9 so as not to vibrate. Coil springs 18 for supporting the vibration table are provided at the four corners of the upper surface of the pedestal 11.

A square plate-shaped vibration table 14 is placed on the pedestal 11 via support springs 18 . Vibration Chiful 14
A support frame 15 extends downward from the lower surface of.

A pair of vibration motors 2+ and 22 are mounted on the support frame 15 of the vibration table 14. and 3 in posture,
Further, the vibration motors 21 and 22 have their rotation axes aligned along a vertical plane including the central axis C, and are tilted at 75 degrees in opposite directions relative to the vibration chamber. The vibration motors 21 and 22 have unbalanced weights 24 fixed to both ends of the rotating shaft, and the centrifugal force caused by the rotation of the unbalanced weights 24 causes the vibration daple 14 to move.
Apply an excitation force in an oblique direction to this object. The pair of vibration motors 21 and 22 are driven such that their frequencies and amplitudes match each other, and their excitation directions are shifted by 1 ((0 degrees. Therefore, this pair of vibration motors 2), 2
When the vibrations caused by 2 are combined, the central axis or the vibration diffle 14
The vibrating daple 14 vibrates along a spiral that coincides with the center line 1 (1 line C). Therefore, the vibration of the vibrating table 14 is not transmitted to the pedestal 11.

Note that instead of the vibration motors 21 and 22, for example, a vibration device using a crank, a cam, or an electromagnet may be used as the vibration device. It is also not limited to what is illustrated.

The bobbin 27 is fixed to the vibration diffle 14+ so that the bobbin holder coincides with the center axis C of the vibration table I4.3, the optical fiber huff is inserted into the hobbin 27, and the wire 1 is wound in a coil shape (( The optical fiber 7 is supplied into the tube from above the coil 5 of this tube.The diameter of the coil 5 of the tube should be 150 mm or more in order not to apply excessive bending stress to the optical fiber. In this embodiment, the optical fiber 7 is an optical fiber wire precoated with resin, and the tube 1 is a steel tube. The outer periphery of the lower flange 29 of the lower flange 29 is fixed to the vibration table 14 using a fixing jig (1).The hobbin 27 has grooves (not shown) so as to be uneven or continuous in the direction of the center of the hobbin in the circumferential direction. is provided so that pipe 1 is in close contact with the groove.

A supply spool 34 of an optical fiber supply device 33 is arranged obliquely on the bobbin 27 . The supply spool 34 is rotatably supported on a bearing stand; The supply spool 34 brings out the optical fiber 7 wound thereon,
The inlet end 3 of the tube 1 is fed.

A drive motor 38 is arranged adjacent to the supply spool 34 , and the supply spool 34 and the drive motor 38 are operatively connected via a belt transmission 40 .

The supply spool 34 is rotationally driven by a drive motor 38 to feed out the optical fiber 7 and supply the optical fiber 7 to the tube 1 wound around the bobbin 27 .

A holding guide 43 is provided close to the optical fiber payout position of the supply spool 34. The holding guide 43 holds the optical fiber 7 paid out from the supply spool 34.

Following the holding guide 43, the optical fiber feeding state detection device 4
7 is placed. Optical fiber feeding state detection device 47
consists of a support column 48 and an optical fiber height position detector 49 attached to the support column 48. The optical fiber height position detector 49 is composed of an image sensor and a light source placed opposite to the image sensor, and is located at a position where the optical fiber 7 passes, and detects the degree of slack in the optical fiber 7. A CCD line sensor is used as the image sensor.

A rotation speed control device 52 is connected to the optical fiber feeding state detection device 47, and the rotation speed control device 52 controls the power source 3 of the drive motor 38 based on the signal from the detection device 47.
9 voltage is controlled. That is, the rotational speed of the drive motor 38, that is, the feeding speed of the optical fiber 7 is controlled in accordance with the height position at which the optical fiber 7 blocks the optical fiber height position detector 49 from the light source.

During insertion of the optical fiber 7 into the tube 1, the insertion speed of the optical fiber 7 is not necessarily constant and may vary depending on the resonance phenomenon and the conditions of the inner surface of the tube and the surface of the optical fiber. Therefore, if the speed of the optical fiber 7 within the tube 1 fluctuates, it will affect the feeding state of the optical fiber 7 outside, and if this feeding speed cannot follow the insertion speed of the optical fiber 7, the optical fiber 7 will be There is a possibility that the above-mentioned slack or disconnection due to excessive tension may occur, which may impede the smooth supply of the optical fiber 7. However, by driving and rotating the supply spool 34 as described above, the optical fiber 7 in the tube 1 is
By changing the rotational speed of the supply spool 34 or stopping it depending on the transport state of the optical fiber 7, it is possible to always supply the optical fiber 7 within a required supply speed range. In other words, the optical fiber 7 can be maintained in the best condition (slightly slack as shown in FIG. 1) without becoming too stretched or too slack. As a result, the optical fiber 7 can be pushed through the tube 1 without any hindrance without putting a burden on the optical fiber 7 itself, that is, without giving any resistance to the insertion of the optical fiber 7. By the way, the diameter is 0
．． When inserting a 4 mm optical fiber into a steel tube with an inner diameter of 0.5 mm, if the force applied to the optical fiber toward the optical fiber supply side is 20 gf or more, the optical fiber will not enter the tube.

A holding guide 5 is provided on the exit side of the optical fiber feeding state detection device 47.
4 and an electromagnetic feeder 55 are arranged. The electromagnetic feeder 55 feeds the optical fiber 7 from the holding guide 54 into the tube entrance end 3.

It is preferable that the inlet/outlet l of the holding guide 43 and 54 be processed into a curved surface without corners, and these materials should be made of a material with a small friction coefficient, such as glass or plastic, so as not to obstruct the transport of the optical fiber 7. Can be used. A solid lubricant made of powder such as carbon, talc, or molybdenum disulfide may be supplied to the surface of the optical fiber 7 passing through the holding guides 43, 54.

A holding fitting 57 is arranged on the exit side of the electromagnetic feeder 55. The inside of the holding fitting 57 is funnel-shaped as shown in FIG.

Next, a method for inserting the optical fiber 7 into the tube 1 using the apparatus configured as described above will be explained.

In advance, the tube 1 is wound around the bobbin 27 in a coil shape to form the coil 5. The tube 1 is not limited to being wound in one layer around the bobbin 27, but is often wound in multiple layers. In this case, the first layer will come into close contact with the groove of the bobbin 27, but the second and subsequent layers will fit between the tubes 1 of the previous layer.

Next, the tube 1 is wound so that the coil axis and the center axis C of the vibration table 14 coincide with each other.

The tip of the tube 1 thus formed into a coil 5 is unwound by one turn of the coil, cut to an appropriate length, and then separated from the tube coil 5 and bent in a horizontal plane. Then,
Pass the 1 end 3 through the hole 58 of the holding fitting 57 and spread it out into a funnel shape. Then, tighten it to the holding fitting 57 with the fitting 59. , the L portion 4 is fixed to the flange 29 of the hobbin 27 with a fastening fitting 61.

First, the supply spool 34 is wound with a pre-coated optical fiber huff. Then, pull out the optical fiber 7 from the supply spool:) 4, and
The distal end portion 8 of the optical fiber huff is positioned from the holding fitting 57 to the front L1 end 3 via the optical fiber feeding state detection device 47, the holding guide 54, and the feeder 55.

Next, the vibration motors 2 and 22 are driven, and the feeder 55 and the drive motor 38 of the spool 34 are driven at the same time.

Since the vibration motors 2+ and 22 are mounted on the vibration table 14 in the position and posture described above, the vibration table 14 receives a torque around the central axis C and a force in the direction of the central axis. As a result, any point on the vibrating daple vibrates along the spiral H shown in FIG. 5 and the inlet section 2.

The entry of the optical fiber into the tube 1 at the start of insertion is explained based on FIGS. 3 and 4 (the tube entrance section 2 in FIG. 3 is shown as a straight tube for convenience). There is a transition point T where the direction of the vibration force coincides with the direction of the center of curvature of the inlet portion 2. In the section between the end 3 and this transition point T (the shaded area in Fig. 3), the optical fiber 7 is No conveying force is generated due to vibrations received from the wall surface.However, in this section, the tip of the optical fiber 7 is not connected to the feeder 5.
Advance by 5. In addition, in this section, the vibration prevents the optical fiber 7 from sliding on the inner wall surface of the tube, reduces the frictional resistance between the optical fiber 7 and the inner wall surface of the tube, and reduces the nf progression by the feeder 55 at the tip of the optical fiber 7. Help.

In the section between the transition point T and the base 4 of the human part 2, the component of the vibration in the transport direction gradually increases.
In other words, the optical fiber 7 between the end 3 and this transition point T is inside the tube, and the forward force from the feeder 55 is acting on it, so the tip of the optical fiber in this section is Forces that prevent forward movement (forces due to centrifugal effects and forces due to static habitus P1 of the rear optical fiber) do not act.

Therefore, if there is even a small conveying force due to vibration (if the angle between the vibration direction and the insertion direction is acute), the tip portion of the optical fiber 7 will move forward. That is, the optical fiber 7
When the tip of the optical fiber passes through the transition point T, the optical fiber moves forward due to the carrying force of the vibration. When the tip of the optical fiber 7 reaches the base 4 of the pawn 11 portion 2, the base 4 is placed at the top end of the tube coil 5, and the optical fiber 7 is placed almost tangent to the tube coil 5. It is inserted into the tube 1 along the direction. After the optical fiber 7 reaches the steady insertion state in this way, the drive of the feeder 55 is stopped tl-, #-. From then on,
The feeder 55 functions as a holding guide.

Incidentally, in the technique disclosed in the above-mentioned Japanese Patent Laid-Open No. 511-186110, as shown in FIG. 5, the tip of the optical fiber is inserted a predetermined distance or the end portion of the optical fiber is inserted before starting insertion. In this method, the optical fiber 7 is connected from the position 11ZI end 3 of the tube 1
It is necessary to apply a conveying force due to vibration to the area of this distance to obtain a conveying force that overcomes the force due to the above-mentioned centrifugal effect and the force due to the static inertia of the optical fiber 7 behind the end of the person 11. That is, there is a point P where the conveyance force due to vibration and the force that prevents the optical fiber from moving forward are equal, and the distance 1i11tL is a distance that exceeds the distance between this point P and the entrance end 3. Even if the tip of the optical fiber 7 is inserted during this time, the optical fiber does not move forward, and the optical fiber huff starts moving forward only after it is inserted beyond the point P.

The optical fiber 7 in the portion of the coil 5 of the tube 1 is advanced by mf by the coil circumferential direction component of the force received from the inner wall of the tube 1,
Go into the tube. Since the coil axis and the central axis C of the vibration table 14 coincide, the optical fiber 7 in the tube moves circularly about the central axis C (in the example of FIG. 2, it moves clockwise P).
circular motion).

The explanation will be given by returning to FIG. 1 again.

When the above spiral vibration is applied to the tube coil 5 via the vibration table 14, the optical fiber 7 supplied from the tube entrance end 3 above the coil 5 continuously enters the tube 1 due to the article conveying force of the vibration. Go. That is, the optical fiber 7 is paid out from the supply spool 34, and is passed through the holding guide 43, the optical fiber feeding state detection device 47, the holding guide 54, and the feeder 5.
5. The pawn L1 end 3, the inlet portion 2, the coiled tube 1, and the tube outlet end are moved in this order by the vibration of the coil 5, and are inserted through the entire coil 5 after a predetermined time.

During the insertion of the optical fiber 7, if the speed of insertion into the pipe changes due to some factor, this will affect the feeding state of the optical fiber 7 at the position of the optical fiber height position detector 49, and this will affect the feeding state of the optical fiber 7 at the position of the optical fiber height position detector 49. It is immediately detected by the detector 49. That is, if the optical fiber height position detector 49 detects that the optical fiber 7 is too tensioned, a signal thereof is sent to the drive motor 38 to increase the spool rotational speed and thereby increase the supply speed of the optical fiber 7. Furthermore, if excessive slack in the optical fiber 7 is detected, the drive motor 38 is similarly controlled to slow down the supply speed of the optical fiber 7.

In this way, abnormal transport conditions of the optical fiber 7 are immediately detected, corrected, and normal transport conditions restored.

(Specific Example) In order to confirm the effects of the present invention, an optical fiber was forced through a steel pipe using the apparatus shown in FIG. 1 under the following conditions.

(1) Test material steel pipe coil: outer diameter (inner diameter) is 0.8 to 2.0 mmφ (0
, 5 to 1.6 mm), 7 types of steel pipes with a length of 10 km were wound in line on a steel bobbin with a winding drum diameter of 1200 mm (10 to 2 mm).
7 types of steel pipe coils (0 layer winding).

A secondary optical fiber was used.

An optical fiber with a diameter of 0.4 mm made by coating a silica glass optical fiber (diameter 125 μm) with silicone resin.

(2) Vibration Condition 2 Since the steel pipe coil used in this example has 10 to 20 winding layers, almost the same vibration conditions are applied to all parts of the pipe.

Vibration angle of the coil with respect to the horizontal plane: 15 degrees Frequency: 20H2 Vertical component of total amplitude: 1', 25 to 1.55 mm As a result of inserting the optical fiber into the steel pipe under the above conditions, the optical fiber can be inserted without pre-insertion and without any trouble. It was inserted smoothly into the steel pipe. The insertion speed was 2 to 4 m/min, and it was confirmed that the entire length of the steel pipe could be penetrated within a predetermined time. Even when inserting an optical fiber into a small diameter tube of 2 mm or less, l
It has been found that it is possible to insert the optical fiber into a long tube of approximately OKm, and of course the quality of the optical fiber does not change.

In the above embodiments, the linear body was an optical fiber, but the present invention can also be applied to the insertion of linear bodies other than optical fibers, such as metal wires such as copper wires and steel wires, or non-metallic wires such as plastics. Ru. The supply of the linear body into the pipe is 1
It is possible to use not only wood but also multiple pieces depending on the inner diameter of the pipe and the diameter of the linear body. In addition to the above-mentioned steel pipe, various specific examples can be considered as the pipe through which the linear body is inserted, such as an aluminum pipe or a synthetic resin pipe. Further, post-processes such as surface reduction processing may be added after the linear body is inserted into the metal tube, and the operator may perform this process as appropriate depending on the situation. Furthermore, the central axis of the tube coil does not necessarily have to coincide with the central axis of the spiral, but it is preferable that both axes coincide, and the central axis of the tube coil does not necessarily have to be perpendicular, but it is perpendicular. It is desirable that there be.

[Effect of the invention] According to this invention, the tube has a small diameter (for example, the outer diameter of the tube is 2 m).
Even if the pipe is long (e.g., pipe length is 1 km or more), it can be inserted without troublesome preliminary insertion and without causing deterioration or damage to the linear body. .

4. Simplification of drawings Qj/, I: Explanation FIG. 1 is a side view showing an example of an apparatus for inserting an optical fiber according to the method of the present invention, and FIG. Fig. 31 is a vertical sectional view showing the fixed state of the Futen 11 portion, Figs. and FIG. 5 respectively show the case according to the conventional method.

1...Pipe, 2...Entrance part of the tube, 3...Pipe person [
-1 end, 5... tube coil, 7... optical fiber, 1
1... Frame, 14... Vibration table, 2], 22.
... Vibration motor, 27... Hobbin, :) 3... Optical fiber supply device, 38... Drive motor, 43, !
i 4... Maintenance 1.1 kite, 47... Optical fiber feeding state detection device, 52... Control device, 55... Electromagnetic feeder, 5! ], [il...tighten (J-fittings).

Claims (1)

[Claims] A tube is wound into a coil to form a tube coil, and while a linear body is supplied from one end of the tube, the tube coil is vibrated so that any point on the tube reciprocates along a spiral path. In the method of inserting a linear body into a tube, the inlet part of the tube is formed so as to be separated from the coil of the tube, the inlet end of the tube is fixedly supported in a stationary state, and the coil of the tube is vibrated while at least the initial stage of insertion. A method for inserting a linear object into a tube, characterized in that the linear object is fed into the inlet end of the tube by a feeder placed near the inlet end of the tube.