JPH0788232B2 - Optical fiber base material manufacturing equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to an apparatus for manufacturing an optical fiber preform for optical communication.

2. Description of the Related Art Conventionally, for example, the VAD method is known as a method for manufacturing an optical fiber preform for optical communication, and the characteristic point of the method is that a soot made of glass fine particles is produced from a long quartz round bar or the like. After depositing on the seed rod, the deposited soot is melted and vitrified.

Therefore, the optical fiber preform manufacturing apparatus generally has an oxyhydrogen burner for spraying soot onto the seed rod tip, and a seed rod is arranged on the oxyhydrogen burner so that the sprayed soot is deposited on the seed rod. The heating apparatus includes a seed rod moving mechanism that raises while rotating, a heating furnace that sinters the deposited soot into transparent glass, and a seed rod transport mechanism that transports the seed rod to the heating furnace.

Problems to be Solved by the Invention However, in the optical fiber preform manufacturing apparatus configured as described above, it is necessary to manually attach and detach the seed rod to and from each mechanism. It was

In addition, it is necessary to separate the installation positions of the oxyhydrogen burner and the heating furnace.Moreover, if soot accumulates, the total length of the seed rod will be about 4 m and the total weight will be about 20 kg, so if human intervention is involved, work There is a problem that not only the performance is bad, but also the burden on the operator is large, and the size of each mechanism is increased, and eventually the size of the entire apparatus is increased.

The present invention has been made in view of the above problems, and an object thereof is to manufacture the optical fiber preform in which the seed rod is automatically attached to and detached from each mechanism to save labor and the overall size of the device is reduced. To provide a device.

Means for Solving the Problems In order to achieve the above object, the present invention has a seed rod carrying-in mechanism having a first arm that grips an intermediate portion of a seed rod, moves up and down, and swivels within a preset range. And a first elevating and lowering unit for holding the upper end of the seed rod that has been raised and swung to a predetermined position by the seed rod loading mechanism, receives the seed rod from the seed rod loading mechanism, and moves the seed rod up and down and rotates. A rotating mechanism, a soot spraying mechanism installed below the first elevating and rotating mechanism to attach the soot to the lower end portion of the seed rod, and an upper end portion of the seed rod is gripped to move up and down and rotate.
Second elevating / rotating mechanism arranged adjacent to the elevating / lowering rotating mechanism and the intermediate portion of the seed rod sufficiently pulled up by the first elevating / lowering mechanism to pivot between the respective elevating / lowering mechanisms. A seed rod moving mechanism having a second arm; a soot sintering mechanism which is installed below the second elevating and rotating mechanism and which turns the soot attached to the seed rod into transparent vitrification; It has a third arm for gripping an intermediate portion of the seed rod sufficiently pulled up by the second elevating / lowering mechanism, receiving the seed rod from the second elevating / lowering mechanism, pivoting to a preset carry-out position, and elevating and lowering. It is characterized by having a carry-out mechanism.

Action In the present invention, therefore, the seed rod is pulled upward after being held at its intermediate portion by the seed rod carry-in mechanism having the first arm in the lowered position, and to the elevating path of the first elevating and rotating mechanism. It can be turned. Then, the seed rod is gripped at its upper end portion by the first lifting / lowering rotation mechanism and transferred from the seed rod loading mechanism to the first lifting / lowering rotation mechanism. After the seed rod loading mechanism is retracted, the first lifting / lowering rotation mechanism is To descend.
As a result, the lower end of the seed rod is lowered to the soot spraying mechanism, and in that state, the soot is sprayed onto the seed rod. During spraying of the soot, the seed rod is slowly rotated and slowly raised by the first elevating and rotating mechanism. When a predetermined amount of soot is deposited and deposited, the first elevating and rotating mechanism pulls up the seed rod to near the upper limit, while the second arm of the seed rod moving mechanism swivels toward the seed rod, Is received from the first elevating and rotating mechanism. The seed rod moving mechanism pivotally moves the seed rod to which the soot is attached to the second raising / lowering rotating mechanism, and the second raising / lowering rotating mechanism grips the upper end portion thereof to receive the seed rod from the seed rod moving mechanism. When the seed rod moving mechanism retracts, the second elevating and rotating mechanism descends, lowers the soot to the soot sintering mechanism, and turns the soot into transparent glass. After the completion of sintering, the second elevating and rotating mechanism pulls up the seed rod, and the carrying-out mechanism having the third arm receives the seed bar and swivels and descends to the carrying-out position. Therefore, with the above structure, the seed rod can be transferred from the mechanism in which the predetermined process has been completed to another mechanism without using human hands. In addition, since the operating range of each mechanism is limited to a preset range, there is no obstacle even if it is downsized.

EXAMPLES Examples of the present invention will be described below with reference to the drawings.

1 to 5 show an embodiment of the present invention.

The optical fiber preform manufacturing apparatus according to the present invention includes an apparatus body 1 including a pedestal member 2 and a column member 20 installed on the upper surface 2a of the pedestal member 2.

The pedestal member 2 is formed in a rectangular parallelepiped shape, and is provided with a soot blowing mechanism 3 on the lower surface 2b side and a soot heating mechanism 9 on the side surface 2c (here, the left side surface).

The soot spraying mechanism 3 is a soot spraying oxyhydrogen burner 5, 6 installed on a burner stand 4 integrated with the lower surface 2b of the base member 2, and a protection member 8 attached to the side surface 2d of the base member 2 by a support tool 8. It is formed with the glass tube 7.

The soot heating mechanism 9 has a heating furnace base 10 approximately at the center of the side surface 2c.
Are integrated and a heating furnace 11 such as a carbon heater having a protective glass tube 12 attached thereto is installed thereon.

The pillar member 20 has a substantially rectangular cross section and its opposite side surfaces.
2a and 2b are provided with first and second seed rod linear feed mechanisms 21 and 24, respectively, along the longitudinal direction, and these are feed screws 22 and 25.
And the holders 23,2 that attach the lead screws 22,25 to the sides 2a, 2b.
It is formed by 6 and.

In addition, the side surface of the pedestal member 2 on the side of the first seed rod linear feed mechanism 21
A seed rod loading mechanism 30 for loading the seed rod 13 into the soot spraying mechanism 3 is installed at 2e.

The seed rod loading mechanism 30 has a mounting portion 38 for mounting the drive portion 31 on the side surface 2e.
And a drive unit 31 which is operated by the drive force of the drive unit 31. The drive unit 31 drives the motor 33 as a drive source for moving the drive unit 34 up and down by a cylindrical guide 32, and a drive force from the motor 33. It is formed by attaching a transmission chain (not shown) for transmitting and a control circuit for controlling the driving force.

The operating portion 34 is fitted with the guide 32 and moves up and down 35.
Moving tool 35 via rotatable arm (first arm) 37
It consists of a chuck 36 to be attached to the
Is set to hold the middle part of the.

The seed rod carry-in mechanism 30 is provided with an instruction circuit (not shown) for instructing attachment / detachment of the seed rod 13 to the chuck 36, holds the intermediate portion of the seed rod 13, and brings the operating portion 34 into the state shown by the two-dot chain line in FIG. Is set so that the seed rod 13 is inserted into the protective glass tube 7 by rotating to the soot spraying mechanism 3 side and descending. Then, when the upper end portion of the seed rod 13 is held by the soot accumulation mechanism 40, the seed rod 13 is opened by the instruction of the instruction circuit and the operating portion 34 returns to the position shown by the solid line in FIG.

The soot accumulation mechanism 40 is mounted on the first seed rod linear feed mechanism 21 so as to be vertically movable and rotatable, but is omitted in FIG. 1 in order to avoid complication of the drawing. A schematic configuration of the soot deposition mechanism 40 is shown from the right side surface side with respect to FIG. In FIG. 4, the soot accumulating mechanism 40 has a pulley 43 for attaching a chuck 42 holding the seed rod 13 to an arm 41 which is mounted on the feed screw 22 so as to be able to move up and down, and for rotating the chuck 42 horizontally. It is formed by mounting a drive source (motor) 44 to which a pulley 45 for driving the pulley 43 is attached.

Further, the soot deposition mechanism 40 is provided with a drive source (not shown) that allows the arm 41 to move up and down, a control circuit that controls the drive source and the drive source 44, and an instruction circuit that instructs the chuck 42 to attach and detach the seed rod 13 and the like. Has been done. The deposition mechanism 40 rotates the chuck 42 at a speed preset in the control circuit so that a certain amount of the soot 14 (see FIG. 2) made of glass particles sprayed from the oxyhydrogen burners 5 and 6 is deposited. The arm 41 is set to move up as it moves. Then, when the accumulation of the soot 14 reaches a preset constant amount, the arm 41 rises to the upper end side of the first seed rod linear feed mechanism 21 (see FIG. 4). The soot deposition mechanism 40 and the first
The seed rod linear feed mechanism 21 and the seed rod linear feed mechanism 21 constitute a first lifting / lowering rotation mechanism.

Here, if the seed rod moving mechanism 50 rotates to hold the intermediate portion of the seed rod 13, the soot depositing mechanism 40 releases the holding of the upper end of the seed rod 13 according to the instruction of the instruction circuit.

The seed rod moving mechanism 50 is installed on the side surface 20c of the strut member 20 facing the soot spraying mechanism 3, and is equipped with a fixture 51 and an arm rotatably mounted on the fixture 51 via a rotation shaft 52 (first 3 arm) 53 and a chuck 54 installed at the tip of the arm 53.

The attachment 51 is provided with a drive source 55 for the arm 53, a control circuit (not shown) for the rotation range of the arm 53, an instruction circuit for instructing attachment / detachment of the seed rod 13 to the chuck 54, and the like.

As shown in FIGS. 1 and 2, this seed rod moving mechanism 50 rotates to the soot heating mechanism 9 side when the middle portion of the seed rod 13 is held, and the soot sintering mechanism 60 that descends moves the seed rod. When the upper end of 13 is held, the seed rod 13 is released and the arm 52 rotates to the side surface.
It returns to the home position indicated by A in FIG. 3 in a state orthogonal to 20c.

Therefore, the rotation range of the seed rod moving mechanism 50 is a range in which the seed rod moving mechanism 50 first rotates to the soot blowing mechanism 3 side and then to the soot heating mechanism 9.

The soot sintering mechanism 60 is mounted on the feed screw 25 of the second seed rod linear feed mechanism 24 so as to be vertically movable and rotatable, and its configuration is the fifth.
As shown in the figure, it is almost the same as the soot deposition mechanism 40.

That is, a chuck 62 that holds the upper end of the seed rod 13 is attached to an arm 61 that is attached to the feed screw 25, and a pulley 63 that rotates the chuck 62 horizontally is attached to the chuck 62.
A drive source 64 attached with a pulley 65 for driving the pulley 63 is attached to the arm 61.

Further, a control circuit for controlling the drive source 64, an instruction circuit for instructing attachment / detachment of the seed rod 13 to the chuck 62, and the like are additionally provided.

This soot sintering mechanism 60 lowers as shown in FIG. 1 when the upper end of the seed rod 13 is held, and inserts the soot 14 into the protective glass tube 12. Then, the chuck 62 rotates at a constant speed and the arm 61 rises according to a control circuit so that the soot 14 is sintered in the heating furnace 11 to become transparent glass. Then, when the transparent vitrification of the soot 14 is completed, the arm 61 moves the feed screw 25.
Ascends to near the top (see Fig. 5). The soot sintering mechanism 60 and the second seed rod linear feed mechanism 24 described above constitute a second lifting / lowering rotation mechanism.

At this time, when the carry-out mechanism 70 rotates to hold the intermediate portion of the seed rod 13, the soot sintering mechanism 60 causes the seed rod to be instructed by the instruction circuit.
Release 13 The carry-out mechanism 70 is installed on the side surface 2c of the pedestal member 2 on the soot heating mechanism 9 side, in a recess 2d provided apart from the soot heating mechanism 9, and has a structure similar to that of the seed rod carry-in mechanism 30.

That is, the driving unit 71 and the mounting unit 78 and the driving unit 71 that are mounted on the side surface 2c.
The driving unit 71 is configured to be operated by the driving force of the driving unit 73. It is formed by mounting a transmission chain and a control circuit for controlling the driving force.

The operating portion 74 is fitted to the guide tool 72 and moves up and down 75.
A moving tool 75 via a rotatable arm (third arm) 77
It consists of a chuck 76 to be attached to the
Is set to hold the middle part of the.

Further, the carry-out mechanism 70 is provided with an instruction circuit (not shown) for instructing the chuck 76 to attach and detach the seed rod 13. And
When the middle portion of the seed rod 13 is held as shown by the solid line in FIG. 2, it rotates to the position shown in FIG. 3 and descends as shown by the chain double-dashed line in FIG. Release 13 and carry it out of the apparatus body 1.

Next, the operation will be described.

First, the operating portion 34 of the seed rod carrying-in mechanism 30 is lowered to the position shown by the solid line in FIG. 1, and the chuck 36 holds the intermediate portion of the seed rod 13. The operating part 34 is raised by the motor 33 to the upper limit shown by the chain line in FIG. 1, and then the arm (first arm) 37 is rotated by the seed rod 13 so as to be positioned in the ascending / descending path of the chuck 42 in the soot depositing mechanism 40. Let At this time, the soot depositing mechanism 40 has been pulled up to a sufficiently high position by the first seed rod linear feed mechanism 21, and after the seed rod 13 has been swung as described above, the soot depositing mechanism 40 is lowered to some extent. The chuck 42 holds the upper end of the seed rod 13. Then, the seed rod carrying-in mechanism 30 releases the grip of the seed rod 13 by the chuck 36, and then returns to its original position. In this way, the seed rod 13 is carried into and delivered to the soot accumulating mechanism 40. The soot deposition mechanism 40 is lowered to the lower limit by the first linear feed mechanism 21, and as a result, the lower end of the seed rod 13 is inserted into the protective glass tube 7 and positioned near the oxyhydrogen burners 5 and 6. In this state, the glass raw material is jetted from the burners 5 and 6 in a flame, and at the same time, the seed rod 13 is pulled up while being rotated, so that the soot is attached and deposited on the seed rod 13 to form a porous fiber preform. When a certain amount of soot is deposited and deposited, the seed rod 13 is held by the soot depositing mechanism 40 and is raised to the upper limit by the first linear feed mechanism 21, while the seed rod moving mechanism 50 described above has an arm (third).
Arm 53 of the seed rod 13 pivots toward the seed rod 13, and the chuck 54 holds the intermediate portion of the seed rod 13. The seed rod moving mechanism 50
Soot deposition mechanism 40 releases seed rod 13 and then soot sintering mechanism
The seed rod 13 is swung to the 60 side to align the seed rod 13 with the ascending / descending path of the chuck 62. At this time, the arm 61 is at the upper limit position and the seed rod 13
The arm 61 moves down a little as the
Hold the top of 13. Then, after the arm 53 of the seed rod moving mechanism 50 returns to its original position and retracts, the soot sintering mechanism 60 is lowered to the lower limit by the second linear feed mechanism 24, and as a result, the soot sintering mechanism adheres to the seed rod 13. The soot thus prepared is inserted into the heating furnace 11 through the protective glass tube 12. While the soot is heated in this state, the seed rod 13 is pulled up while being rotated by the soot sintering mechanism 60, and as a result, it is zone-melted and defoams and becomes transparent to form a transparent optical fiber preform. . After the sintering is carried out in this way, the soot sintering mechanism 60 rises, and the arm of the carry-out mechanism 70 (third arm) located at the upper limit to this.
77 swivels toward the soot sintering mechanism 60 side to grip the middle portion of the seed rod 13 and receives the seed rod 13 from the soot sintering mechanism 60. Then, after the arm 77 has swung to the position shown by the solid line in FIG.
It is lowered to the lower limit by the drive source 73 together with the operating part 74, and is sent to the next step at the carry-out position shown by the chain line in FIG.

In the above-described embodiment, the operations such as raising, lowering, turning and rotating are performed by the feed screw, the chain or the motor, but in the present invention, these operations may be performed by another driving mechanism. .

EFFECTS OF THE INVENTION As is apparent from the above description, according to the present invention, the series of operations from the loading and unloading of the seed rod is carried out by the mechanisms for raising, lowering, rotating, and swiveling, so that the optical fiber matrix can be delivered. The material can be automatically produced without human intervention, and thus the work efficiency can be improved, and the burden on the operator can be reduced, and particularly, the long and heavy large-sized base material can be manufactured. Can be easily manufactured. Further, since the lifting and lowering range of each mechanism is limited to a preset range, each apparatus can be downsized even as an apparatus for manufacturing a long and heavy base material, so that the entire apparatus can be downsized. Can be achieved. Moreover, the durability of each mechanism is improved by limiting the range of elevation and rotation, and the occurrence of failure can be prevented, so that the reliability can be improved. Therefore, the present invention is particularly suitable for manufacturing a large-sized optical fiber preform having a long length and a large weight.

[Brief description of drawings]

1 to 5 show an embodiment of the present invention, FIG. 1 is a partially omitted front view of an apparatus main body of an optical fiber preform according to the present invention, FIG. 2 is a left side view of FIG. FIG. 3 is a plan view of FIG. 1, and FIGS. 4 and 5 are mechanical views of a soot deposition mechanism and a soot sintering mechanism. 1 ... Device body, 2 ... Pedestal member, 2a ... Top surface, 3 ...
Soot spraying mechanism, 9 ... Soot heating mechanism, 13 ... Seed rod,
14 ...... Soot, 20 ...... Support member, 21 ...... First type rod linear feed mechanism, 24 ...... Second type rod linear feed mechanism, 30 ...... Seed rod loading mechanism, 40 ...... Soot accumulation mechanism, 50 ... … Seed rod moving mechanism, 60
...... Soot sintering mechanism, 70 …… Unloading mechanism.

Claims (1)

[Claims] 1. A seed rod carry-in mechanism having a first arm that grips an intermediate portion of the seed rod and ascends and descends and swivels within a preset range, and ascends to a predetermined position by the seed rod carry-in mechanism. A first elevating / rotating mechanism that holds the upper end of the swiveled seed rod and receives the seed rod from the seed rod carrying-in mechanism and elevates and rotates the seed rod, and is installed below the first elevating / rotating mechanism. A soot spraying mechanism that attaches soot to the lower end of the seed rod and a second lifting and lowering unit that grips and lifts and rotates the upper end of the seed rod and is arranged adjacent to the first lifting and rotating mechanism. A rotating mechanism; and a seed rod moving mechanism having a second arm that grips an intermediate portion of the seed rod sufficiently pulled up by the first elevating and rotating mechanism and pivots between the elevating and rotating mechanisms. Is installed below the lifting and rotating mechanism of the A soot sintering mechanism that turns the deposited soot into transparent glass and a middle part of the seed rod sufficiently pulled up by the second elevating and rotating mechanism to hold the seed rod in a second elevating and lowering rotation. And a unloading mechanism having a third arm which is received from the mechanism and is rotated to a preset unloading position and is moved up and down.