WO2002050594A1 - Device and method for manufacturing metal tube-covered optical fiber cable - Google Patents

Abstract

A device and a method for manufacturing a metal tube-covered optical fiber cable; the method, comprising the step of, while manufacturing a metal tube (6) by forming a metal tape (2) in a tubular body and welding the joint of the metal tube (2), feeding an optical fiber (11) protected by a jerry substance into the metal tube (6) through a guide pipe (13) inserted in to the metal tube (6) so that the tip thereof is positioned ahead of a welded position, wherein a damage of the guide pipe (13) by welding heat is reduced to increase the service life of the optical fiber, and a welding torch (5) for welding the joint of the metal tape (2) is reciprocatingly moved along the joint for welding, whereby the welding heat can be prevented from being concentrated into one position on the guide pipe.

Description

 TECHNICAL FIELD The manufacturing apparatus and the manufacturing method of a metal tube coated optical fiber cable

The present invention relates to an apparatus for manufacturing a metal tube-coated optical fiber cable used for an optical fiber composite overhead ground wire and the like. More specifically, the present invention relates to a method for forming a metal tube from a metal tape and forming an optical fiber inside the formed metal tube. The present invention also relates to a manufacturing apparatus and a manufacturing method for manufacturing a metal-coated optical fiber cable by inserting a gap between the optical fiber and the metal tube with a die-like substance. Background art

The metal tube-coated optical fiber cable is formed by forming a metal tape into a tubular body and welding the seam of the metal tape to produce a metal tube, and is inserted into the metal tube so that the tip is located before the welding position. It is manufactured by feeding an optical fiber into the metal tube through a guide pipe (for example, JP-A-4-350808). Such an optical fiber cable is manufactured using, for example, an apparatus as shown in FIG. In this manufacturing apparatus 1, a metal tape 2, for example, a stainless steel tape is formed into a tubular body using a plurality of forming holes 3, and the abutting portions of both side edges of the metal tape 2 are welded by a welding machine 5. To form a metal tube 6. At the same time, the optical fiber 11 and the jelly-like substance 12, for example, a liquid synthetic resin, are introduced into the metal tube 6 by using the introduction tube 4 to manufacture an optical fiber cable. 'The guide pipe used here is welded by Tig welding, for example, but serves to protect the optical fiber from being damaged by welding heat. Guide pipes may also be used to carry waterproof shells along with optical fibers into metal tubes. In addition, as shown in FIG. 1, the optical fiber 11 is supplied via introduction pipes 7 and 4. Then, the shell-like substance 12 is supplied from the tank 9 to the introduction pipe 4 via the supply pipe 8 by the pump 10. The introduction pipe 4 is extended to the tip (the moving direction of the optical fiber) beyond the place where the metal pipe 6 is welded, and has an action of preventing damage to the die-like substance and the optical fiber due to heat generated during welding. is there. The first object of the present invention is to provide a conventional apparatus in which a seam of a metal tape formed on a traveling tubular body is welded with a welding torch installed at a fixed position, so that the seam is directly below a welding torch of a guide pipe. Area is susceptible to thermal damage. For this reason, holes may be formed in the guide pipe, and the coating of the optical fiber inside may be melted by heat, or the shell-like substance may boil and blow out. Even if there is no hole in the guide pipe, the guide pipe may be deformed by welding heat, and the distance between the metal tape and the guide pipe may change, which may hinder welding.

It is therefore an object of the present invention to provide an apparatus for manufacturing a metal tube-coated optical fiber cable that solves the above problems. Die-like substance that fills the gap between the optical fiber and the metal tube fixes the optical fiber in the metal tube, waterproofs the optical fiber, and protects the optical fiber from lateral pressure. It is. A second object of the present invention is that the dieri-like substance has a high viscosity and cannot be supplied at a predetermined pressure from the start of production. Therefore, even when the pump 10 is started to be driven, the die-like substance does not immediately flow out of the inlet pipe 4 into the inside of the metal pipe 6, and after a short time elapses, the die-like substance comes out of the inlet pipe 4. Discharge starts gradually into the metal tube 6. Then, it is only after the pump 10 is started that the die-like substance starts to flow stably into the metal pipe 6 at the set flow rate R s (for example, 40 g Z) from the introduction pipe 4. For example, after about 2 minutes have passed. As described above, since it takes a long time from the start of driving of the pump 10 to the stable supply of the die-like substance into the metal tube 6, the production of the optical fiber cable has just started. In the early stage of the manufacture of the optical fiber cable, there is a problem that the jelly-like substance is not introduced into the metal tube 6 of the optical fiber cable, or a defective portion with a small amount of the die-like substance is produced.

 Accordingly, a second object of the present invention is to immediately stabilize the supply of a diele-like substance to a metal tube immediately after starting the production of an optical fiber cable, and to reduce the occurrence of defects in the initial stage of production due to the diele-like substance. It is an object of the present invention to provide an optical fiber cable manufacturing apparatus capable of performing the above.

 An object of the present invention is to provide a manufacturing apparatus capable of solving the above problems and manufacturing a metal-coated optical fiber having stable performance and function. Disclosure of the invention

 The present invention provides an apparatus for producing a metal-coated optical fiber, comprising the following members.

 (1) a forming device for forming a metal tube from a metal tape to form a metal tube for coating an optical fiber;

 (2) a device for supplying a die-like substance for protecting the optical fiber inserted into the molded tubular body to the metal tube;

 (3) a joining device arranged on a forward / backward retractable stage for joining the joined portion of the formed tubular body,

 (4) A tubular guide that guides the metal tape and protects the optical fiber when joining the formed tubular body. Further, the present invention provides a method for producing a metal-coated optical fiber, comprising the following steps.

(1) a step of forming a metal tape on a tubular body to form a metal tube covering the optical fiber; (2) a step of introducing a die-like substance for protecting the optical fiber inserted into the molded tubular body into an introduction pipe for protecting the optical fiber inserted into the tubular body;

 (3) A step of joining the formed metal pipes while moving forward and backward. BRIEF DESCRIPTION OF THE FIGURES

 FIG. 1 is a diagram showing an outline of an apparatus for manufacturing an optical fiber cable.

 FIG. 2 is a side view showing an embodiment of the apparatus for manufacturing a metal tube-coated optical fiber cable according to the present invention.

 FIG. 3 is a diagram showing a preferable relationship between the line speed and the moving speed of the joining torch when implementing the present invention.

 FIG. 4 is a diagram showing a preferred embodiment of the moving speed when the joining torch is moved periodically in the present invention.

 FIG. 5 shows an example of the relationship between the elapsed time from the start of the production of the optical fiber cable and the flow rate of the jelly-like substance discharged to the metal tube in the embodiment of the present invention in comparison with the conventional example. FIG.

 FIG. 6 is an explanatory diagram showing one embodiment of the pressure control of the device for supplying a die-like substance according to the present invention.

 FIG. 7 is a diagram showing a pressure control mode of the device for supplying the jelly-like substance.

 FIG. 8 is a diagram illustrating drive amount control of a pressurizing pump including a preload control unit in a further embodiment of the present invention.

 FIG. 9 is a diagram showing a pressure control mode of a jelly-like substance in a further embodiment of the present invention. Detailed description of the invention

 Hereinafter, embodiments of the present invention will be specifically described.

A first aspect of the present invention is an apparatus for manufacturing a metal-coated optical fiber, comprising the following members. (1) a forming device for forming a metal tape on a tubular body to form a metal tube for covering an optical fiber;

 (2) an apparatus for supplying a tubular material for protecting the optical fiber inserted into the molded tubular body to the tubular body;

 (3) a joining device arranged on a forward / backward retractable stage for joining the joined portion of the formed tubular body,

 (4) A tubular guide that guides the metal tape and protects the optical fiber when joining the formed tubular body.

 A second aspect of the invention is the manufacturing apparatus according to claim 1, wherein the forming apparatus is a roll forming apparatus including a roll having a plurality of U-shaped force rivers.

 A third aspect of the present invention is the manufacturing apparatus, wherein the die-like substance for protecting the optical fiber is a liquid synthetic resin.

 A fourth aspect of the present invention is the manufacturing device, wherein the joining device is a welding device.

 A fifth aspect of the present invention is the manufacturing apparatus, wherein the welding apparatus is a TIG welding apparatus.

 A sixth aspect of the present invention is the manufacturing apparatus, wherein the welding apparatus is a plasma welding apparatus.

 A seventh aspect of the present invention is the manufacturing apparatus, wherein the welding apparatus is a laser welding apparatus.

An eighth aspect of the present invention is a manufacturing apparatus further comprising a guide roll for guiding the joined tubular body in the vicinity of the stage.A ninth aspect of the present invention further comprises: The stage is further provided with a guide roll for guiding a tubular body to be joined. In a tenth aspect of the present invention, a stage provided with the joining device is formed into a tubular shape. A manufacturing apparatus characterized in that it is a stage that advances and retreats at a predetermined cycle in the advancing direction of the optical fiber when joining the shaped contact portions. An eleventh aspect of the present invention is the manufacturing apparatus, wherein a forward and backward speed of the stage is equal to or lower than a line speed of the optical fiber.

 A twelfth aspect of the present invention is the manufacturing apparatus characterized in that the advance speed of the stage is higher than the retreat speed.

 According to a thirteenth aspect of the present invention, in the supply device for a dieli-like substance, a tank for storing the substance, a pipe for supplying the substance from the tank to a molded metal tape before joining, and the pipe And a valve for controlling a supply amount of the substance.

 A fifteenth aspect of the present invention is the manufacturing apparatus, further comprising a pressure sensor for the substance provided between the pump and the valve. The pressure pump is a pump which is operated at a pressure higher than a predetermined steady supply pressure for a predetermined time based on a signal from the pressure sensor before starting the production of the optical fiber.

 According to a sixteenth aspect of the present invention, there is provided a second pipe which is provided between the pump and the valve via a control valve for further stably supplying the jelly-like substance, and a pre-pressure control for controlling these pressures. This is a manufacturing apparatus characterized by including the apparatus.

 In a seventeenth aspect of the present invention, the manufacturing apparatus further includes a control device that controls a driving amount of the pressurizing pump based on the pump and a pressure sensor that measures a pressure of the supplied gel-like substance. A manufacturing apparatus characterized in that:

 An eighteenth aspect of the present invention is a method for producing a metal-coated optical fiber, comprising the following steps.

(1) a step of forming a metal tape on a tubular body to form a metal tube covering the optical fiber; (2) Inserted into the molded tubular body

Introducing the fibrous substance into an introduction tube for protecting an optical fiber inserted in the tubular body;

 (3) A step of joining the joined portions of the formed tubular bodies while moving forward and backward. A ninth aspect of the present invention is the manufacturing method, wherein the forming step is performed by a roll forming apparatus including a roll having a plurality of u-shaped force rivers.

 A twenty-fifth aspect of the present invention is the manufacturing method, wherein the joining is a welding method.

 A twenty-first aspect of the invention is a manufacturing method characterized in that the welding method is a TIG welding method.

 A twenty-second aspect of the present invention is the manufacturing method, wherein the welding method is a plasma welding method.

 A twenty-third aspect of the present invention is the manufacturing method, wherein the welding method is a laser welding method.

 A twenty-fourth aspect of the invention is characterized in that the joining is performed while advancing and retreating at a predetermined cycle with respect to the traveling direction of the optical fiber when joining the contact portions of the metal tape formed on the metal tube. Manufacturing method.

 A twenty-fifth aspect of the present invention is the manufacturing method, wherein the forward and backward speed is equal to or lower than the optical fiber line speed.

 A twenty-sixth aspect of the present invention is the manufacturing method, wherein the forward speed is higher than the reverse speed.

 A twenty-seventh aspect of the present invention is the manufacturing method, wherein the step of supplying the dieli-like substance is performed while maintaining the pressure in the supply pipe of the dieli-like substance at a predetermined pressure.

A twenty-eighth aspect of the present invention is the manufacturing method, characterized in that the supply pressure is maintained at a pressure higher than a predetermined steady supply pressure for a predetermined time before starting the production of the optical fiber. A twentieth aspect of the present invention is the manufacturing method, further characterized in that the supply pressure of the dieli-like substance is maintained while measuring the pressure while controlling the pressure by a driving amount of a pressure pump. is there. Hereinafter, the present invention will be described with reference to the drawings. However, the present invention is merely one embodiment of the present invention, and is not limited thereto. Is included. Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings. FIG. 1 shows a typical manufacturing apparatus as described above. In this conventional manufacturing apparatus, a metal tape formed into a tubular body is welded with a welding torch having a fixed contact surface with a roll having a U-shaped caliber. In one embodiment of the present invention shown in FIG. 2, the metal tape 2, for example, a stainless steel tape or an aluminum tape, etc., is a force rib that forms it into a cylindrical, often cylindrical, or elliptical shape. It is formed into a tubular body having a predetermined shape by a forming roll 3 provided with the above. After that, the metal tape 2 formed on the tubular body is joined by a joining torch for joining seams, for example, a welding torch 5. As the joining method, TIG welding, plasma welding, or laser welding such as excimer laser, YAG laser, or carbon dioxide laser can be appropriately selected. The welded metal pipe 6 is drawn in the direction of arrow P at a line speed of, for example, about 10 m / min. In this figure, the guide pipe 13 is installed such that the tip is located in the metal pipe 6 ahead of the position of the welding torch U (on the right side in the drawing). The optical fiber 2 is fed into the metal pipe 16 through the guide pipe 13, and the gel-like substance 12 is sent into the supply pipe 6 via the inlet pipe 4. In FIG. 2, since the introduction pipe 4 and the guide pipe 13 are separately provided, the introduction pipe 4 also has an effect of protecting the optical fiber against the welding torch. In addition, as shown in FIG. 1, the optical fiber 11 and the die-like substance 11 can be supplied together through the introduction tube 4.

In the apparatus of the present invention, when manufacturing a metal tube-coated optical fiber cable, a joining apparatus, for example, a welding torch 5 is connected to a metal tape 2 formed into a tubular body. Welding is performed while reciprocating (between the solid line and the broken line) along the seam. In this case, the position of the guide pipe 13 heated by the welding torch 5 changes in the longitudinal direction, so that thermal damage is reduced as compared with the case where the guide pipe 13 is locally heated as in the past. The possibility of receiving is greatly reduced. As a result, the life of the guide pipe 13 is prolonged, and the frequency of replacement of the guide pipe 13 can be drastically reduced. As a result, a longer metal tube-coated optical fiber cable can be manufactured. Further, in this manufacturing apparatus, since the guide pipe 13 does not move, the optical fiber 11 can be fed smoothly, and the optical fiber 11 is less likely to be damaged. Various devices for reciprocating the welding torch 5 are conceivable. For example, a stage 50 capable of sliding in the running direction of the metal pipe 6 is installed on the base 51, and the welding torch 5 and the guide are mounted on the stage 50. The stage 50 is mounted on the base 5 1 with the guide roll 5 3 and the welding torch 5 maintained in such a way that the positional relationship between the guide roll 5 3 and the welding torch 5 is always kept above the joint of the metal tape. It is recommended to use a structure that is reciprocated by an actuary that is fixed at 52 km. The stage 50 reciprocates, for example, at a speed of about 5 mm / min over a distance of 100 mm. In this way, even if the metal tube-coated optical fiber cable was continuously manufactured for about 15 hours, the guide pipe 18 did not have a hole. With conventional equipment with a fixed welding torch, the guide pipe was punctured in 3 to 5 hours, greatly extending the service life.

 In FIG. 2, the guide roll 53 is provided so as to move together with the welding torch 5, but may be supported on a support different from the welding torch 5, in which case the guide roll 53 is fixed. May be provided, or may be provided so as to be movable in the longitudinal direction of the metal tube.

As shown in Fig. 3, the moving speed of the welding torch 5 (moving speed of the stage 50) is lower than the line speed (moving speed of the metal tube 16). It is preferable to perform control in proportion to This is because when the line speed is high, the amount of heat input from the welding torch increases, so that the welding torch is moved quickly to minimize the effect of welding heat on the guide pipe. Also, as shown in Fig. 4, the moving speed of the welding torch 5 in which the welding torch moves forward and backward is controlled so that when the welding torch moves in the direction opposite to the moving direction of the metal tube, it is lower. Is preferred. By doing so, the relative speed (forward welding speed) between the welding torch 5 and the metal tube 6 when the welding torch moves in the traveling direction of the metal tube, and the welding speed when the welding torch moves in the opposite direction. The difference between the relative speed (reverse welding speed) of the torch and the metal tube can be reduced, and the welding conditions are stable, so that a good welding condition can be obtained over the entire length. As described above, according to the present invention, the welding is performed while the welding torch 5 is reciprocated along the joint of the metal tape, thereby reducing damage to the guide pipe 13 due to welding heat. This can extend the life of the guide pipe. As a result, the frequency of replacing the guide pipe is reduced, and the production efficiency can be improved. In addition, it is possible to manufacture a longer metal fiber-coated optical fiber cable. In addition, since the guide pipe may be kept stationary, damage to the optical fiber due to movement of the guide pipe can be avoided, and the incidence of defects can be reduced. Further, in the optical fiber cable manufacturing apparatus 1 of the present invention, a special supply and manufacturing apparatus for the diele-like substance 12 is provided. In contrast to the manufacturing apparatus disclosed in FIGS. 1 and 2 described above, the pump 10 supplies the die-like substance in the supply pipe 8 for a certain period of time from the manufacturing start time in the pipe passage downstream of the pump 10. As shown in FIG. 6 as an opening and closing device for opening and closing, a first valve 21 for controlling pressure and a pressure control device are provided. The most characteristic feature of this embodiment is that before starting the production of the optical fiber cable, the pump 10 is driven with the first valve 21 closed to drive the pump 10 and the first valve 2. After performing a pre-pressure operation to increase the pressure of the jelly-like substance in the eight supply pipes between the first, the first valve 21 is opened to start the production of the optical fiber cable. Note that any manufacturing method after the start of the manufacturing of the optical fiber cable may be adopted, and the description thereof is omitted here.

 The driving operation of the pump 10 and the opening / closing operation of the first valve 21 related to the preload operation of the die-like substance 12 may be manually operated. FIG. 1 shows an example of a configuration for automatically controlling the driving operation of the first valve 21 and the opening and closing operation of the first valve 21. For example, in the first pressure control example, a pressure sensor device 22 for detecting the pressure inside the pipe is provided at a portion of the die-like substance supply pipe 8 between the pump 10 and the first valve 21. ing. A pressure control device 20 for controlling the optical fiber cable manufacturing device 1 automatically controls the operation of the pre-pressure operation of the jelly-like substance.

 The pressure and pressure control unit 20 for the die-like substance, for example, fetches information from the pressure sensor device 22 and the like and uses the fetched information in a control procedure as shown in the flowchart of FIG. A structure is provided for automatically controlling the pump 10 and the first valve 21. That is, for example, when the pressure control unit 20 detects that a command to start the device operation has been issued based on operation information of the operation start button by an operator or the like (step S 1 in FIG. 7), When the first valve 21 is closed, the pump 10 is started to be driven (step S 2). The jelly-like substance in the die-like substance supply pipe 8 between the pump 10 and the first valve 21 is removed. Start applying pressure.

Then, the pressure control unit 20 fetches the detected value of the pressure sensor device 22 every moment (step S3), and converts the fetched detected value to the set pressure value. Compare to determine whether the detected value has reached the set pressure value (Step

S 4). By the way, when the drive of the pump 10 is started in a state where the first valve 21 is opened, as shown by a chain line in FIG. 5, the pressure inside the die-like substance supply pipe 8 gradually increases with time. Start to rise. Then, from the time when the die-like substance starts to be stably supplied into the metal pipe 6 with the set flow rate R s from the introduction pipe 4, the pressure of the die-like substance in the die-like substance supply pipe 8 becomes a substantially constant pressure value. Stable to Ps. The pressure value P s (pressure value when the die-like substance is stably supplied from the introduction pipe 4 to the metal pipe 6 at the set flow rate R s) required for this is obtained by calculation, experiment, or the like. The obtained pressure value Ps is given to the pressure control unit 20 in advance as the set pressure value. The pressure controller 20 compares the set pressure value Ps with the detected value of the pressure sensor device 22 and determines that the detected value of the pressure sensor device 22 has reached the set pressure value Ps. Then, the first valve 21 is opened (step S5). In this embodiment, similarly, the drive of the roll 3 and the supply of the optical fiber from the optical fiber supply pipe 7 to the introduction pipe 4 are started, and the production of the optical fiber cable is started. According to this first pressure control example, the die-like substance supply pipe 8 is provided with the first valve 21 at a position downstream of the pump 10 and before starting the production of the optical fiber cable, Since the pump 10 is driven while the first valve 21 is closed to perform a pre-pressure operation for increasing the pressure of the die-like substance in the supply pipe 8 between the pump 10 and the first valve 21, the first valve 2 From the time of opening the valve 1 and starting the production of the optical fiber cable, as shown in Fig. 5, the die-like substance is stabilized with the set discharge flow rate R s from the inlet pipe 4 to the inside of the metal pipe 6. It will be able to be supplied in an appropriate manner. As a result, It is possible to almost eliminate defects in the initial stage of IVA cable manufacturing and to reduce waste. Next, a second pressure control example different from the first pressure control example will be described. In the description of this embodiment, the same components as those of the first pressure control example will be denoted by the same reference numerals, and redundant description of the common portions will be omitted.

In the method of manufacturing an optical fiber cable according to the second pressure control example, as shown in FIG. 8, a pressure adjusting device 3 4 is attached to a die-like substance supply pipe 8 between the pump 10 and the first valve 21. For example, a second valve 31 is provided. The pressure adjusting device 34 includes a pipe (vent line) 32 having substantially the same inner diameter as the shell-like substance supply pipe 8 and a pipe 3 having a diameter smaller than the inner diameter of the pipe 32 and having substantially the same inner diameter as the inlet pipe 4. 2 and the second valve 31 provided between the pipe 33 is controlled. In the pressure regulator 34, one end of the pipe 32 is connected in communication with the die-like substance supply pipe 8 between the pump 10 and the first valve 21, and a pipe is connected to the other end of the pipe 32. One end of the pipe 33 is connected, and the other end of the pipe 33 can be connected to, for example, a tank 9 of diele-like substance. In addition, the other end of the pipe 33 can be connected to the supply pipe 8 to circulate the die-like substance to control the pressure. Since the pipe 32 and the thinner pipe 33 are connected to the pressure regulator 34, the pump 1 is closed with the first valve 21 closed and the second valve 31 opened. By driving 0, it is possible to increase the pressure of the gel-like substance in the supply pipe 8 portion between the pump 10 and the first valve 21 and, even if there is any fluctuation in the pressure of the gel-like substance, It is possible to stabilize the pressure at the specified setting. In the second pressure control example, the set pressure value P s (the jelly-like substance is stably supplied from the introduction pipe 4 to the metal pipe 6 at the set flow rate R s shown in the first pressure control example. Is set as the above set pressure. In the second pressure control example, the pressure of the die-like substance in the supply pipe 8 between the pump 10 and the first valve 21 is determined by the pre-pressure operation of the die-like substance before starting the production of the optical fiber cable. The first valve 21 is opened after the pressure of the die-like substance is stabilized by the pressure adjusting device 34. At the same time, production of optical fiber cables will begin. Any method may be adopted after the start of the production of the optical fiber cable, and any description thereof will be omitted.

 In the second pressure control example as well, the optical fiber cable is manufactured after the pre-pressurizing operation of the dialy substance is started. Therefore, similarly to the first pressure control example, a defect caused by the die-like substance in the initial stage of manufacturing is performed. Can be almost eliminated. In the second pressure control example, as in the first pressure control example, the driving operation of the pump 10 and the opening and closing operations of the first valve 21 and the second valve 31 relating to the pre-pressure operation of the gel-like substance are performed manually. The configuration example of automatic control for operating the pump 10 and the valve 11 is shown below. In the optical fiber cable manufacturing apparatus shown in the second pressure control example, the above-mentioned second valve 31 is provided, and the following preload control section 30 is provided. The other device configuration is almost the same as the device configuration shown in the first pressure control example. In this second pressure control example, the pressure sensor device 22 need not be provided if the pressure is set in advance to the same value as in the first pressure control example.

In the second pressure control example, when the optical fiber cable manufacturing apparatus 1 stops operating, the first valve 21 is closed and the second valve 31 is open. . For example, when detecting that the start command of the device operation is issued, the preload control unit 30 keeps the first valve 21 closed and the second valve 31 open. Start pump 10 drive. By driving the pump 10, the pressure of the shell-like substance in the supply pipe 8 is increased. Then, when a predetermined valve opening condition is satisfied, the preload control unit 30 closes the second valve 31 and opens the first valve 21. At the same time, production of optical fiber cables will begin. Thus, the first valve 21 and the second valve 31 may be ordinary mechanical valves or electromagnetic valves. Further, the control device 34 may be a mechanical handle or a control device that is electromagnetically operated. The above-mentioned valve opening condition is a condition indicating that the pressure of the jelly-like substance in the supply pipe 8 is stabilized at a substantially set pressure by the preload control unit 30. For example, since the time from when the pump 10 starts to drive until the pressure of the gel-like substance in the supply pipe 8 starts to stabilize to the substantially set pressure by the second valve 31 is almost fixed, The time is obtained, and the fact that the time (for example, 2 minutes) has elapsed since the drive of the pump 10 was started can be given as the valve opening condition. With such a preload control section 30, the preload operation before starting the production of the optical fiber cable can be automatically operated.

In addition, the second valve 31 is provided with a die-like material in the part of the die-like material supply pipe 8 between the pump 10 and the first valve 21 during the pre-pressure operation of the die-like material before starting the production of the optical fiber cable. What is necessary is just to provide a structure capable of adjusting the pressure of the substance, and it is not limited to a mechanical valve. For example, instead of the pipe 33 which is a thin pipe in the pipe (vent line) 32, a flow control device such as a needle valve, which can variably control the flow rate of the jelly-like substance in the pipe 32, is provided in the pipe 32. It may be provided. For example, when a needle valve is provided, the needle valve should be set so that the jelly-like substance in the supply pipe 8 between the pump 10 and the first valve 21 has the set pressure during the pre-pressure operation of the gel-like substance. The opening is controlled. Hereinafter, a third pressure control example will be described. In the optical fiber cable manufacturing apparatus of the third pressure control example, when an optical fiber cable is manufactured using the optical fiber cable manufacturing apparatus 1 as shown in FIG. 1 or FIG. At the start of cable manufacturing, as shown in FIG. 9, the pump 10 is driven with a drive amount larger than the pump drive amount Js during the steady operation of the optical fiber cable manufacture. As a result, the rise of the pressure of the dieli-like substance is increased as shown by the solid line A from the dotted line B of the pressure of the dieli-like substance in the conventional supply pipe 8. Thus, the supply of the dieleic substance from the introduction pipe 4 to the metal pipe 6 can be accelerated. In this embodiment, it may be used in other optical fiber cable manufacturing apparatuses. Although the drive amount control of the pump 10 may be performed manually, an example of a configuration for automatically controlling the pump 10 is shown here. For example, the control device of the optical fiber cable manufacturing apparatus 1 is provided with a pump drive control section 40 (see FIG. 1) for controlling the pump 10. In this embodiment, the pump drive control section 40 is provided with a pump drive amount J s at the time of steady operation and a pump drive amount J p at the start of operation in advance.

The pump driving amount J s during the steady operation is the driving amount of the pump 10 when the jelly-like substance is stably supplied from the introduction pipe 4 to the inside of the metal pipe 6 at the set flow rate R s. . In addition, the pump drive amount J p at the start of operation is a drive amount larger than the pump drive amount J s at the time of steady operation, and is appropriately set in consideration of various points such as the capacity of the pump 10. ing. In this embodiment, the information on the pump drive amounts J s and J p is given to the pump drive control unit 40 by information on the rotation speed of the pump 10. The pump drive control unit 40 drives the pump 10 with the pump drive amount Jp at the start of operation, for example, when the start of operation of the optical fiber cable is detected based on the operation information of the operation start button by the operator. . Then, the pump drive control unit 40 operates the pump 10 according to a program given in advance. The drive amount of the pump is gradually reduced toward the pump drive amount JS during the steady operation, and from the time when the die-like substance starts to be supplied stably from the introduction pipe 4 to the metal pipe 6, the pump 10 is switched to the pump during the steady operation. A configuration is provided in which driving is performed with the driving amount Js.

According to this embodiment, at the start of the production of the optical fiber cable, the drive amount of the pump 10 is set to be larger than that at the time of the steady operation. As a result, the supply of the die-like substance from the inlet pipe 4 to the metal pipe 6 is accelerated, and the initial production of the optical fiber cable due to the absence of the die-like substance or the shortage of the die-like substance. Can be greatly reduced. Further, in the third pressure control example, the supply pipe 8 was not provided with the first valve 21, the pressure sensor device 12, or the pressure adjustment device 34, and the pump 1 By simply increasing the zero drive amount compared to normal operation, it is possible to greatly reduce defects in the initial stage of fiber optic cable manufacturing, and to achieve great results with the structure of the conventional manufacturing equipment. it can. Note that the present invention is not limited to the above embodiments, and various embodiments can be adopted. For example, in the first or second pressure control example, the set pressure value Ps is the pressure of the shell-like substance in the supply pipe 8 when the jelly-like substance is stably supplied from the introduction pipe 4 to the metal pipe 6. However, an appropriate value other than this pressure value may be used as the set pressure value. Further, in the second pressure control example, the pressure sensor device 22 is omitted. However, similarly to the first pressure control example, the pressure sensor device 22 may be provided. In this case, the pressure sensor device confirms that the pressure of the jelly-like substance in the substance supply pipe 8 is increased by the preload operation, and that the pressure is stabilized by the preload controller 30. The valve 21 can be opened when it is detected based on the detection value of the position 22. A pump and an opening / closing device for the passage are provided in the introduction passage 8 at a position downstream of the pump, and the pump is driven with the opening device such as a valve closed before starting the production of the optical fiber cable. When the pre-pressurizing operation of the die-like substance is performed to increase the pressure of the die-like substance in the substance introduction passage between the pump and the switch, the switch is opened, and then the production of the optical fiber cable is started. In this case, the production of optical fiber cables started when the pressure of the die-like substance in the part of the die-like substance introduction passage between the pump and the switch was increased by the pre-pressure operation of the die-like substance. Therefore, it is possible to supply the die-like substance from the die-like substance introduction passage to the inside of the metal tube at a substantially set flow rate from the start of the production. As a result, it is possible to almost eliminate defects in the initial stage of manufacturing the optical fiber cable due to the absence of the diele-like substance or the lack of the diele-like substance. Also, in the invention in which the driving amount of the pump is made larger than the pump driving amount at the time of the steady operation at the start of the production of the optical fiber cable, the pressure rise of the die-like substance in the die-like substance introduction passage is made higher than before. It can be much faster. As a result, the stability of the supply of the diele-like substance from the die-like substance introduction passage to the metal tube can be accelerated, and as described above, the production of an optical fiber cable due to the absence of the diele-like substance or the shortage of the die-like substance Initial failures can be almost eliminated.

Furthermore, in the case of a system equipped with a structure that automatically controls the operation of the pump and the switchgear during the preload operation, for example, pressing the operation start button without the trouble of manually operating the pumps and the switchgears By itself, a series of work operations of the preload operation can be automatically performed. This allows It is possible to greatly reduce defects in the initial stage of manufacturing an optical fiber cable without bothering workers. Industrial applicability

In the present invention, the present invention has been described as a new apparatus for manufacturing a metal-coated optical fiber. However, similar effects can be obtained by using the present invention as an apparatus for manufacturing an optical fiber coated with a plastic tape instead of a metal tape. Also. This is a manufacturing device that can be applied to cases where various wires are coated with metal or plastic instead of optical fibers.

Claims

The scope of the claims 1. An apparatus for manufacturing a metal-coated optical fiber, comprising:  (1) a forming device for forming a metal tape into a tubular body for forming a metal tube for covering an optical fiber;  (2) a device for supplying a die-like substance for protecting an optical fiber inserted into the molded tubular body to the metal tube;  (3) a joining device arranged on a forward / backward retractable stage for joining the joined portion of the formed tubular body,  (4) A tubular guide that guides the metal tape and protects the optical fiber when joining the formed tubular body.  2. The manufacturing method according to claim 1, wherein the forming device is a roll forming device including a roll having a plurality of U-shaped force ribs. 3. The manufacturing apparatus according to claim 1, wherein the die-like substance for protecting the optical fiber is a liquid synthetic resin.  4. The manufacturing device according to claim 1, wherein the joining device is a welding device. 5. The manufacturing device according to claim 4, wherein the welding device is a TIG welding device.  6. The manufacturing apparatus according to claim 4, wherein the welding apparatus is a plasma welding apparatus.  7. The manufacturing device according to claim 4, wherein the welding device is a laser welding device.  8. The manufacturing apparatus according to claim 1, further comprising a guide roll for guiding the tubular body to be joined, near the stage. 9. The manufacturing apparatus according to claim 1, wherein the stage further includes a guide roll for guiding a tubular body to be joined. 10. The stage provided with the joining device is characterized in that when joining the abutting portion of the metal tape formed into a tubular body, the stage moves forward and backward at a predetermined cycle in the traveling direction of the optical fiber. Claim 1 11. The manufacturing apparatus according to claim 8, wherein a forward and backward speed of the stage is lower than a line speed of the optical fiber.  12. The manufacturing apparatus according to claim 8, wherein a forward speed of the stage is higher than a backward speed.  1 3. The supply device of the dieli-like substance includes: a tank for storing the substance; a pipe for supplying the substance from the tank to a formed metal tape before joining; and a pressure pump provided in the middle of the pipe. The manufacturing apparatus according to claim 1, further comprising: a valve configured to control a supply amount of the substance.  14. The manufacturing apparatus according to claim 13, further comprising a pressure sensor for the substance provided between the pump and the valve.  15. The pressure pump is a pump which is operated for a predetermined time at a pressure higher than a predetermined steady supply pressure based on a signal from the pressure sensor before starting the production of an optical fiber. 13.The manufacturing apparatus according to 3, 16. In the middle of the pump and the valve, a second pipe for supplying the jelly-like substance through a control valve for stably supplying the substance and a pre-pressure control device for controlling these pressures are provided. The manufacturing apparatus according to claim 13, wherein:  17. The manufacturing apparatus further includes a control device for controlling a driving amount of the pressurizing pump based on the pump and a pressure sensor for measuring a pressure of the supplied slurry-like substance. Item 13. The manufacturing apparatus according to Item 13.  1 8. A method for manufacturing a metal-coated optical fiber, comprising the following steps. (1) a step of forming a metal tape on a tubular body to form a metal tube covering the optical fiber; (2) a step of introducing the shell-like substance inserted into the molded tubular body into an introduction tube for protecting the optical fiber inserted into the tubular body;  (3) A step of joining the joined portions of the formed tubular bodies while moving forward and backward. 19. The manufacturing method according to claim 18, wherein the forming step is performed by a roll forming apparatus provided with a roll having a plurality of U-shaped force ribs.  20. The manufacturing method according to claim 18, wherein the joining is a welding method.  21. The manufacturing method according to claim 20, wherein the welding method is a TIG welding method.  22. The manufacturing method according to claim 20, wherein the welding method is a plasma welding method.  23. The manufacturing method according to claim 20, wherein the welding method is a laser welding method.  24. The method according to claim 18, wherein the joining is performed while advancing and retreating at a predetermined cycle with respect to the traveling direction of the optical fiber when joining the contact portions of the metal tape formed into the tubular body. Manufacturing method.  25. The manufacturing method according to claim 18, wherein the forward and backward speed is equal to or lower than the optical fiber line speed.  26. The method according to claim 18, wherein the forward speed is higher than the reverse speed.  27. The method according to claim 18, wherein the step of supplying the dieli-like substance is performed while maintaining the pressure in the supply pipe of the dieli-like substance at a predetermined pressure. 28. The method according to claim 27, wherein the supply pressure is maintained at a pressure higher than a predetermined constant supply pressure for a predetermined time before starting the production of the optical fiber. 29. The manufacturing method according to claim 27, further comprising maintaining the supply pressure of the dieri-like substance while measuring the pressure and controlling the pressure by a driving amount of a pressurizing pump.