Device for conveying optical fiber porous preform

Abstract

To provide a conveyance device without damaging a burner in a step of conveying an optical fiber porous preform.SOLUTION: A device for conveying an optical fiber porous preform, capable of extracting the optical fiber porous preform deposited in the horizontal state from the inside of a deposition device includes: a mainframe; a leg provided in the mainframe and including a conveyable mechanism; two arm parts provided in the mainframe; a workpiece support mechanism provided in the tips of the arm parts and including a wire rope; and a winding-up mechanism provided in the mainframe and moving the workpiece support mechanism in the vertical direction by winding up and down the wire rope. The arm part and the workpiece support mechanism hang and support both ends of the optical fiber porous preform from above.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an apparatus for transporting a porous preform for an optical fiber from inside a deposition chamber to outside the deposition chamber.

Background Art

[0002] Methods known as the VAD, MCVD method, and OVD method are known for a porous preform for an optical fiber formed by depositing glass particles.

[0003] A process for obtaining a porous preform for an optical fiber using the OVD method will be described with reference to FIG. 1. As shown in FIG. 1(a), a seed rod 1 including a core and a part of a cladding has handles 2 welded to both ends thereof and is gripped by a rotary chuck 4 as a target rod 3. Opposite to the target rod 3, a burner 6 fixed to a burner base 5 is provided. The burner base 5 is driven left and right along the target rod 3 and back and forth toward the target rod 3. In addition to glass raw materials such as silicon tetrachloride, trichloro(methyl)silane, octamethylcyclotetrasiloxane, etc., oxygen and hydrogen are supplied to the burner 6, and glass particles are generated by a flame hydrolysis reaction in the flame 7. While generating glass particles with the burner 6, the burner base 5 reciprocates along the target rod 3, so that the remaining part of the cladding on the rotating target rod 3 is deposited as glass particles in layers. Both ends of the deposited glass particles are tightened by side burners 8 and serve to prevent cracking during deposition. These series of deposition processes are performed in a deposition chamber 9 called a chamber.

[0004] The deposited glass particles form a porous preform 10 for an optical fiber as shown in FIG. 1(b). As the outer diameter of the porous preform 10 for an optical fiber increases, the burner base 5 is retracted. After a desired deposition amount is obtained, the supply of the glass raw material and oxygen / hydrogen to the burner 6 is stopped to obtain a desired porous preform for an optical fiber.

[0005] After the deposition is completed, the optical fiber porous base material needs to be transported from the deposition chamber to the outside. Therefore, Patent Document 1 proposes a method of carrying out the optical fiber porous base material by supporting the handle portions at both ends from below with a transport arm.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] There is a burner 6 for depositing glass fine particles or a side burner 8 for heat-shrinking the glass fine particles at both ends below in the deposition chamber. When inserting the transport arm from below the lower part of the porous base material for optical fiber, there is a possibility of damaging these burners.

[0008] Therefore, the present invention has been made in view of such problems, and an object of the present invention is to provide a transport device that does not damage the burner in the transport process of the porous base material for optical fiber.

Means for Solving the Problems

[0009] The present invention solves such problems, and the transport device for the porous base material for optical fiber of the present invention is a transport device that takes out the porous base material for optical fiber deposited in a horizontal state from the deposition device, and includes a main frame, legs provided on the main frame and having a transport mechanism, two arm portions provided on the main frame, a work support mechanism provided at the tip of the arm portion and having a wire rope, and a winding mechanism provided on the main frame for moving the work support mechanism in the vertical direction by winding up and winding down the wire rope, and is characterized in that the arm portion and the work support mechanism support both ends of the porous base material for optical fiber by suspending them from above.

[0010] In the present invention, the transport mechanism provided on the legs is preferably a caster. Further, the winding-up mechanism is preferably an electric winch or a manual winch. Further, the work support mechanism is preferably composed of a wire rope and a hook.

[0011] In the present invention, it is preferable that the work support mechanism supports both ends of a tapered portion or both ends of a handle portion of the porous base material for an optical fiber.

[0012] In the present invention, it is preferable that the wire rope passes through at least one pulley connected to a spring before reaching the winding-up mechanism via the arm portion.

[0013] In the present invention, it is preferable that the structure is such that the wire rope joins a single wire rope at the center in the left-right direction of the main frame before reaching the winding-up mechanism, and a single wire rope is wound around the winding-up mechanism.

Advantages of the Invention

[0014] According to the transport device for the porous base material for an optical fiber of the present invention, it becomes possible to transport the porous base material for an optical fiber from the deposition chamber to the outside without damaging the burner.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0016] The conveying device for the porous base material for optical fibers according to the present invention has a main frame, legs provided on the main frame and having a transport mechanism, and two arm portions provided on the main frame. The arm portion has a work support mechanism at its tip. The main frame has a hoisting mechanism for moving the work support mechanism in the vertical direction. Then, the arm portion and the work support mechanism support both ends of the porous base material for optical fibers by suspending them from above.

[0017] The legs are equipped with casters, and it is possible to move the entire conveying device. The main frame is equipped with a hoisting mechanism such as an electric winch or a hand winch, and it is possible to move the work support mechanism at the tip of the arm portion up and down by winding up and down a wire rope. The work support mechanism is composed of a wire rope and a hook. It is possible to directly suspend and support the handle portions at both ends of the porous base material for fibers using the hook of this work support mechanism, or it is also possible to suspend and support a tapered portion at both ends of the porous base material for fibers by using a sling on the hook.

[0018] The wire rope of the work support mechanism passes through at least one pulley connected to a spring until it reaches the hoisting mechanism via the arm portion. Thereby, it is possible to absorb sudden impacts during conveyance and prevent the porous base material for optical fibers from being damaged.

[0019] Also, before the wire rope reaches the hoisting mechanism, it joins a single wire rope at the center in the left - right direction of the main frame, and finally, the wire rope wound around the hoisting mechanism is a single one. That is, by rotating the hoisting mechanism forward or backward, it is possible to move the work support mechanisms on the two arms up and down synchronously.

[0020] Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. FIGS. 2 and 3 are schematic views of a conveying device 20 for a porous base material 10 for an optical fiber according to the present invention. FIG. 2 is a front view of the conveying device 20, drawn such that the left - right direction in the figure is the left - right direction of the conveying device 20. Further, FIG. 3 is a side view of the conveying device 20, drawn such that the left in the figure is the front of the conveying device 20.

[0021] The base of the conveying device 20 of the present invention is composed of a main frame 21, two leg portions 22 provided on the main frame 21, and two arm portions 24.

[0022] The leg portions 22 have casters 23 that enable the entire conveying device 20 to move. The movement of the entire conveying device 20 may be achieved by manually pushing the main frame or by rotating the casters 23 electrically.

[0023] As shown in FIGS. 2 and 3, the main frame 21 is arranged to extend upward from the rear end portion of the leg portions 22. The main frame 21 includes not only the main struts forming the skeleton but also beams, braces, etc. that reinforce the strength of the conveying device 20. The arm portions 24 are provided to project forward and laterally from the upper end portion of the main frame 21. A wire rope 25 and a hook 26 constituting a work support mechanism 27 hang down from the tip of the arm portion 24. The amount of projection of the arm portion 24 forward and laterally is determined according to the dimensions of the porous base material 10 for an optical fiber to be conveyed so that the porous base material 10 for an optical fiber suspended by hanging the hook 26 on the handles 2 at both ends does not interfere with the main frame 21 or the manufacturing device.

[0024] The main frame 21 is equipped with a winding - up mechanism 31. It is preferable to use a manual winch or an electric winch for the winding - up mechanism 31. By winding up and winding down the wire rope 25 with this winding - up mechanism 31, the porous base material for an optical fiber suspended from the tip of the arm portion 24 is moved up and down.

[0025] The wire rope 25 reaches the hoisting mechanism 31 from the arm portion 24 via the main frame 21. The two wire ropes 25 merge into one by the wire rope fastening portion 30 at the center in the left-right direction of the main frame. The wire rope after merging into one is wound around the hoisting mechanism 31. With such a structure, when the hoisting mechanism 31 is rotated forward or backward, the work support mechanism 27 hanging down from the two arm portions 24 can be moved up and down synchronously.

[0026] The wire rope 25 passes through several pulleys 29 before reaching the hoisting mechanism 31. Thereby, the direction through which the wire rope 25 passes is changed. Further, the shock absorption mechanism 28 using the pulley 29 has the effect of absorbing sudden shocks during the conveyance of the porous base material 10 for optical fibers.

[0027] The shock absorption mechanism 28 will be described in detail with reference to FIGS. 4 and 5. As shown in FIG. 4, the shock absorption mechanism 28 includes three pulleys 29 through which the wire rope 25 passes. One of the three pulleys 29 in the center is fixed to the displacement pedestal 36 and is connected to the spring 34 via the displacement pedestal 36. The remaining two pulleys 29 are fixed to the pedestal 32 on both sides of the one in the center. A nipple 37 is slidably attached to the displacement pedestal 36. A bush 35 is provided in the through hole of the displacement pedestal 36. The nipple 37 is passed through this bush 35, and the displacement pedestal 36 is structured not to fall off from the nipple 37 by a nut 33 attached to one end of the nipple 37. The bush 35 enables the displacement pedestal 36 to slide smoothly upward when receiving a load. Further, the nipple 37 penetrates inside the spring 34 which is a coil spring and is fixed to the pedestal 32 by a nut 33. One end of the spring 34 is attached to the displacement pedestal 36, and the other end abuts against the nut 33 that fixes the nipple 37 to the pedestal 32. When a sudden shock is applied to the conveyance device 20 when the porous base material 10 for optical fibers is being conveyed, the spring 34 is compressed as shown in FIG. 5(b) to absorb the shock. The conveyance device 20 can thus stably convey the porous base material 10 for optical fibers.

[0028] Figure 6 is a view showing the porous base material 10 for optical fiber being suspended from above by the work support mechanism 27. In this figure, the handles 2 at both ends of the porous base material 10 for optical fiber are supported. By using a sling for the hook, it is also possible to support a part of the taper.

[0029] As described above, the transfer device 20 according to the present invention does not insert the transfer arm from below the porous base material for optical fiber, but suspends and supports both ends of the porous base material for optical fiber from above by the work support mechanism. Therefore, the porous base material for optical fiber can be transferred from the deposition chamber to the outside without damaging the burner.

Explanation of Reference Numerals

[0030] 1 seed rod 2 handles 3 target rod 4 rotary chuck 5 burner base 6 burner 7 flame 8 side burner 9 deposition chamber 10 porous base material for optical fiber 20 transfer device 21 main frame 22 legs 23 caster 24 arm part 25 wire rope 26 hook 27 work support mechanism 28 shock absorption mechanism 29 pulley 30 wire rope fastening part 31 hoisting mechanism 32 pedestal 33 nut 34 spring 35 bush 36 displacement pedestal 37 nipple

Claims

1. A conveying device for taking out a porous base material for an optical fiber deposited in a horizontal state from within a deposition apparatus, comprising: a main frame; legs provided on the main frame and having a transport mechanism; two arm portions provided on the main frame; a work support mechanism provided at the tip of the arm portion and having a wire rope; a hoisting mechanism provided on the main frame for moving the work support mechanism in the vertical direction by winding up and down the wire rope; and a conveying device for a porous base material for an optical fiber, characterized in that the arm portion and the work support mechanism support both ends of the porous base material for an optical fiber by suspending them from above.

2. The conveying device for a porous base material for an optical fiber according to Claim 1, wherein the transport mechanism provided on the legs is a caster.

3. The conveying device for a porous base material for an optical fiber according to Claim 1 or 2, wherein the hoisting mechanism is an electric winch or a manual winch.

4. The conveying device for a porous base material for an optical fiber according to Claim 1 or 2, wherein the work support mechanism is composed of a wire rope and a hook.

5. The conveying device for a porous base material for an optical fiber according to Claim 1 or 2, wherein the work support mechanism supports both ends of a tapered portion or both ends of a handle portion of the porous base material for an optical fiber.

6. The conveying device for a porous base material for an optical fiber according to Claim 1 or 2, wherein the wire rope passes through at least one pulley connected to a spring before reaching the hoisting mechanism via the arm portion.

7. The conveying device for a porous base material for an optical fiber according to Claim 1 or 2, wherein the wire rope merges into one wire rope at the center in the left-right direction of the main frame before reaching the hoisting mechanism.

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