JP6880098B2 - Manufacturing equipment for porous glass fine particles and manufacturing method for optical fiber base material - Google Patents

Description

The present invention relates to an apparatus for producing porous glass fine particles and a method for producing an optical fiber base material.

Conventionally, an apparatus for producing a porous glass fine particle body as shown in Patent Document 1 has been known. In this apparatus for producing porous glass fine particles, a raw material gas is supplied to a burner ignited by a pilot fire, and the raw material gas is reacted to generate glass fine particles. An optical fiber base material is obtained by depositing glass fine particles on a target member to form a soot layer, and heating and sintering the soot layer.

Japanese Patent No. 5683198

Here, when supplying the raw material gas to the burner, it is required to detect the ignition of the pilot fire. As in the configuration of Patent Document 1, it is possible to detect the ignition of the pilot fire by detecting the temperature of the shielding plate, but considering that the thermal power of the pilot fire is small, it is improved in terms of responsiveness and accuracy. There was room for.

The present invention has been made in consideration of such circumstances, and an object of the present invention is to improve the responsiveness and accuracy when detecting a pilot fire of a burner.

In order to solve the above problems, the apparatus for producing porous glass fine particles according to the first aspect of the present invention includes a burner having a flammable gas outlet, a temperature sensor capable of measuring temperature, and the like. A detection target portion whose temperature is measured by the temperature sensor is provided, and the detection target portion projects from the spout to the side where the flammable gas is ejected in a direction along the central axis of the spout. ..

Further, the method for producing an optical fiber base material according to the second aspect of the present invention includes a step of ejecting a flammable gas from a combustible gas outlet of a burner and igniting the combustible gas, and a step of igniting the combustible gas By measuring the temperature of the detection target portion protruding from the ejection port to the side where the flammable gas is ejected in the direction along the central axis, the pilot fire generated by the combustion of the flammable gas is ignited. In the step of determining whether or not the combustible gas is burning, the raw material gas is supplied to the burner, and the glass fine particles generated by reacting the raw material gas are adhered to the target member to be porous. It includes a step of obtaining a quality glass fine particle body and a step of sintering the porous glass fine particle body.

According to the above aspect of the present invention, it is possible to improve the responsiveness and accuracy when detecting the pilot fire of the burner.

It is the schematic of the manufacturing apparatus which concerns on 1st Embodiment. It is an enlarged view near the burner of FIG. It is sectional drawing of the burner in the manufacturing apparatus which concerns on 2nd Embodiment. FIG. 3 is a sectional view taken along line IV-IV of FIG. It is sectional drawing of the burner in the manufacturing apparatus which concerns on the modification of 2nd Embodiment. FIG. 5 is a cross-sectional view taken along the line VI-VI of FIG. It is sectional drawing of the burner in the manufacturing apparatus which concerns on other modification of 2nd Embodiment. FIG. 7 is a cross-sectional view taken along the line VIII-VIII of FIG.

(First Embodiment)
Hereinafter, the apparatus for producing the porous glass fine particles of the first embodiment and the method for producing the optical fiber base material will be described with reference to the drawings.
As shown in FIG. 1, the apparatus for producing porous glass fine particles (hereinafter, simply referred to as the production apparatus 10) includes a chamber 2 and a plurality of burners 3. The target member 1 is housed in the chamber 2. The target member 1 is a member that is a core of the porous glass fine particle body manufactured by the manufacturing apparatus 10. The target member 1 is made of quartz or the like. Both ends of the target member 1 are rotatably supported by chucks.

(Direction definition)
In the present embodiment, the direction along the central axis O (see FIG. 2) of the combustible gas ejection port 3a in the burner 3 is referred to as the central axis direction. The Y-axis direction in FIG. 1 represents the central axis direction, and the Z-axis direction represents the vertical direction. Further, the target member 1 side in the central axis direction is referred to as a + Y side (one side), and the burner 3 side is referred to as a −Y side (the other side). The + Y side is the side on which the flammable gas is ejected from the ejection port 3a.

In the example of FIG. 1, the longitudinal direction of the target member 1 is substantially orthogonal to the vertical direction. That is, the target member 1 extends in the substantially horizontal direction. Further, the central axis direction (Y-axis direction) is also substantially orthogonal to the vertical direction. The configuration of the manufacturing apparatus 10 can be changed as appropriate. For example, the longitudinal direction of the target member 1 may be substantially parallel to the vertical direction. Further, the central axis direction may be parallel to the vertical direction, or may be inclined at a predetermined angle with respect to the horizontal direction.

An opening 2a extending along the longitudinal direction of the target member 1 is provided on the −Y side of the chamber 2. On the + Y side of the chamber 2, an exhaust portion 2b is provided to exhaust the combustible gas or the like that has been burned.
Each burner 3 is provided in the opening 2a of the chamber 2. The burner 3 is configured to traverse and circulate the sections (X1 → X2 → X3 → X4 → X1) in the drawing by an external traversing means (not shown).

Note that each burner 3 does not have to circulate as shown in FIG. 1 as long as it can move relative to the target member 1 in the longitudinal direction of the target member 1. For example, each burner 3 may be reciprocated in the longitudinal direction of the target member 1. Alternatively, each burner 3 may be fixed and the target member 1 may be reciprocated in the longitudinal direction thereof.

Combustible gas, auxiliary gas, raw material gas, seal gas, and purge gas are supplied to each burner 3 from various gas supply sources (not shown). As the flammable gas, H ₂ gas or the like is used. As the combustion assisting gas, O ₂ gas or the like is used. As the raw material gas, such as SiCl ₄ gas is used.

The purge gas is used to prevent so-called flashback by extruding flammable gas or flammable raw material gas from the burner 3 after stopping the supply of the raw material gas to the burner 3. As the purge _{gas, an inert gas such as N 2} gas, He gas, Ne gas, and Ar gas is used.

The seal gas is used to prevent the reaction products and energy from adversely affecting the tip of the burner 3 by delaying the contact between the gases ejected from the burner 3 and delaying the start of the reaction for a desired time. For example, if the raw material gas comes into contact with the oxyhydrogen flame immediately after being ejected from the ejection port 3a, the generated glass fine particles may adhere to the burner 3. Therefore, by delaying the reaction of the raw material gas with the seal gas, it is possible to prevent the glass fine particles from adhering to the burner 3. As the sealing gas _{, an inert gas such as N 2} gas or Ar gas is used. The composition of each gas can be changed as appropriate.

FIG. 2 is an enlarged view of the vicinity of the tip portion of the burner 3 of FIG. The alternate long and short dash line O in FIG. 2 shows the central axis of the combustible gas ejection port 3a of the burner 3. In the present embodiment, the burner 3 is formed in a cylindrical shape coaxial with the central axis O, but the burner 3 does not have to be cylindrical. Further, in the present embodiment, the central axis O of the ejection port 3a extends along a substantially horizontal direction, but the direction in which the central axis O extends can be appropriately changed.

As shown in FIG. 2, the manufacturing apparatus 10 of the present embodiment includes a detection target unit 6, a temperature sensor 7, an ignition unit 8, a control unit 9, and a light wave detection unit 20. The ignition unit 8 ignites the flammable gas. As the ignition unit 8, a spark plug, a heater having an ignition point or higher of the flammable gas, or the like can be used.

One detection target unit 6 is provided for each burner 3. The detection target portion 6 is a portion that is heated when the pilot fire 4 is ignited by burning a flammable gas in the burner 3. Of the detection target units 6, the point at which the temperature sensor 7 actually detects the temperature is referred to as a detection point 6b. In the present embodiment, the detection point 6b is located on the outer surface of the tip portion 6a of the detection target portion 6. The tip portion 6a is a portion of the detection target portion 6 that protrudes to the + Y side from the ejection port 3a.

The temperature sensor 7 is a contact type sensor or a non-contact type sensor that detects the temperature of the detection point 6b of the detection target unit 6. A thermocouple can be adopted as the contact type sensor, and a radiation thermometer can be adopted as the non-contact type sensor. When a thermocouple is used as the temperature sensor 7, the detection point 6b is set not on the inner surface of the detection target portion 6 but on the outer surface to prevent the substances constituting the thermocouple from adhering to the target member 1. it can.

The light wave detection unit 20 is a non-contact type sensor that detects light waves in the vicinity of the combustible gas ejection port 3a of the burner 3. The light wave detection unit 20 detects the light wave emitted by the pilot fire 4 and outputs the detection result to the control unit 9. The light wave detection unit 20 may detect infrared rays, ultraviolet rays, or visible light.

The temperature sensor 7 and the light wave detection unit 20 are connected to the control unit 9 by wire or wirelessly. The temperature sensor 7 outputs the measured temperature of the detection target unit 6 to the control unit 9, and the light wave detection unit 20 outputs the light wave detection result to the control unit 9. The control unit 9 determines whether or not the pilot fire 4 is ignited based on both the temperature of the detection target unit 6 measured by the temperature sensor 7 and the light wave detection result by the light wave detection unit 20. In this way, by determining whether or not the pilot fire 4 is ignited based on the two means, the accuracy of the determination by the control unit 9 can be further improved.

The control unit 9 burns one or both of the flammable and raw material gas when at least one of the determination results based on the temperature sensor 7 and the light wave detection unit 20 determines that the pilot fire 4 is not ignited. It may be configured to cut off the supply to 3.
The manufacturing apparatus 10 does not have to include the light wave detection unit 20. In this case, the control unit 9 may determine whether or not the pilot fire 4 is ignited based only on the measurement result by the temperature sensor 7.

The detection target unit 6 is fixed to the burner 3. Therefore, when the burner 3 moves with respect to the target member 1, the detection target portion 6 also moves together with the burner 3. The detection target portion 6 is formed in a cylindrical shape that surrounds the ejection port 3a from the outside. The shape of the detection target portion 6 can be changed as appropriate, but when the central axis O is not parallel in the vertical direction, it is preferable that at least a part of the detection target portion 6 is located above the ejection port 3a.

The temperature sensor 7 may or may not be fixed to the detection target portion 6. For example, when a thermocouple is used as the temperature sensor 7, the thermocouple may be fixed to the detection target unit 6 so that the thermocouple and the detection target unit 6 move together with the burner 3 when the burner 3 moves. Alternatively, when a radiation thermometer is used as the temperature sensor 7, the detection target unit 6 reaches a predetermined position when the burner 3 and the detection target unit 6 move without fixing the temperature sensor 7 to the detection target unit 6. When this happens, the temperature of the detection target unit 6 may be measured by the temperature sensor 7.

Further, when the temperature sensor 7 is not fixed to the detection target unit 6, the temperature of a plurality of detection target units 6 may be measured by one temperature sensor 7. For example, the temperature sensor 7 may be set to measure the temperature at a predetermined position, and when the detection target unit 6 reaches the predetermined position, the temperature of the detection target unit 6 may be measured. Good.

The light wave detection unit 20 may or may not be fixed to the detection target unit 6 as in the temperature sensor 7. Further, one light wave detection unit 20 may detect the light waves emitted by the pilot fires 4 of the plurality of burners 3. For example, the light wave detection unit 20 may be set to detect the light wave at a predetermined position, and the light wave may be detected when the outlet 3a of the flammable gas of the burner 3 reaches the predetermined position. Further, in order to limit the detection range of the light wave by the light wave detection unit 20, a shielding plate provided with a slit may be arranged between the light wave detection unit 20 and the ejection port 3a of the burner 3.

Here, the detection target portion 6 of the present embodiment protrudes from the ejection port 3a toward the target member 1 side (+ Y side) in the direction along the central axis O of the ejection port 3a (central axis direction). In FIG. 2, the detection target portion 6 is formed in a tubular shape, and the tip portion 6a of the cylinder is located on the + Y side of the ejection port 3a. When the flammable gas is supplied to the burner 3, the flammable gas ejected from the ejection port 3a flows to the + Y side along the central axis direction. Therefore, the pilot fire 4 also flows to the + Y side, and the pilot fire 4 heats the tip portion 6a of the detection target portion 6 protruding to the + Y side.

Further, since the combustible gas burned gradually goes upward, the pilot fire 4 also goes upward as well as toward the + Y side. Therefore, as shown in FIG. 2, since at least a part of the detection target portion 6 is located above the ejection port 3a, the detection target portion 6 is heated more reliably.

Next, a method for manufacturing the optical fiber base material according to the present embodiment will be described.

First, the target member 1 is set in the chamber 2.
Next, the flammable gas is supplied to the burner 3 and ejected from the ejection port 3a. Then, the ignition unit 8 ignites the flammable gas to generate a pilot fire.

Next, the temperature of the detection target unit 6 is measured by the temperature sensor 7, and the measurement result is output to the control unit 9. Based on the measurement result, the control unit 9 determines whether or not the flammable gas is burned to generate a pilot fire. When the manufacturing apparatus 10 includes the light wave detection unit 20, the control unit 9 generates flammable gas based on both the temperature measurement result by the temperature sensor 7 and the light wave detection result by the light wave detection unit 20. Determine if it is burning.

Next, the raw material gas is supplied to the burner 3 in a state where the flammable gas is burned to generate a pilot fire. Glass fine particles are produced by reacting the raw material gas with an oxidation reaction or a hydrolysis reaction. A porous glass fine particle body is obtained by depositing glass fine particles on the surface of the target member 1 to form a soot layer while rotating the target member 1.

Next, an optical fiber base material is obtained by heating and sintering the soot layer of the porous glass fine particles.
Further, an optical fiber can be manufactured by drawing the optical fiber base material with a spinning furnace.

As described above, the apparatus 10 for producing the porous glass fine particles of the present embodiment includes a burner 3 having a flammable gas outlet 3a, a temperature sensor 7 capable of measuring a temperature, and a temperature sensor 7. A detection target unit 6 whose temperature is measured by Then, as shown in FIG. 2, in the direction along the central axis O of the flammable gas ejection port 3a, the detection target portion 6 projects from the ejection port 3a to the side (+ Y side) where the flammable gas is ejected.

With this configuration, when the pilot fire ignites the burner 3, the detection target portion 6 is rapidly heated by the pilot fire as compared with the case where the detection target portion 6 does not protrude from the ejection port 3a. Therefore, by detecting the temperature of the detection target unit 6 with the temperature sensor 7, it is possible to accurately and quickly detect whether or not the pilot fire is ignited even when the thermal power of the pilot fire is small. ..

Further, the central axis O of the spout 3a is not parallel to the vertical direction, and at least a part of the detection target portion 6 is located above the spout 3a. With this configuration, the detection target portion 6 is heated more quickly by the pilot fire going upward from the ejection port 3a. Therefore, the temperature sensor 7 that measures the temperature of the detection target unit 6 can detect the ignition of the pilot fire more quickly and accurately.

Further, when the detection target portion 6 is made of quartz, the optical fiber produced even if the constituent substance of the detection target portion 6 or the substance generated by the constituent substance adheres to the target member 1. It does not easily affect the quality of the base material. Therefore, quartz is suitable as the material of the detection target portion 6. However, the detection target portion 6 may be formed of a material other than quartz in consideration of the quality required for the optical fiber base material.

Further, as shown in FIG. 2, the detection point 6b is located at the tip portion 6a of the detection target portion 6. With this configuration, the detection point 6b is heated more quickly by the pilot fire 4, so that it is possible to detect whether or not the pilot fire 4 is ignited more quickly. In particular, when the detection target portion 6 is made of a material having a relatively low thermal conductivity such as quartz, if the detection point 6b is set at a position away from the tip of the detection target portion 6, the pilot fire 4 causes the detection point. The above configuration is suitable because it takes time for 6b to be heated. It should be noted that, among the tip portions 6a, by providing the detection point 6b at a position closer to the tip on the + Y side of the detection target portion 6, it is possible to detect whether or not the pilot fire 4 is ignited more quickly. ..

Further, the method for manufacturing the optical fiber base material of the present embodiment includes a step of ejecting a flammable gas from the combustible gas outlet 3a of the burner 3 and igniting the combustible gas, and a central axis O of the ejection port 3a. By measuring the temperature of the detection target portion 6 protruding from the ejection port 3a to the side (+ Y side) where the flammable gas is ejected in the direction along the line, is the pilot fire generated by the combustion of the flammable gas ignited? The step of determining whether or not the gas is combustible, the raw material gas is supplied to the burner 3 while the flammable gas is burning, and the glass fine particles generated by reacting the raw material gas are attached to the target member 1 to form a porous glass. It has a step of obtaining a fine particle body and a step of sintering a porous glass fine particle body.

By such a manufacturing method, the responsiveness and accuracy at the time of detecting the pilot fire of the burner 3 can be improved. Further, for example, since it is possible to avoid supplying the raw material gas to the burner 3 when the pilot fire is not ignited, it is possible to stabilize the amount of glass fine particles generated and stabilize the quality of the optical fiber base material. it can. In addition, it is possible to suppress the release of harmful gas or flammable gas in an unreacted state.

(Second Embodiment)
Next, the second embodiment according to the present invention will be described, but the basic configuration is the same as that of the first embodiment. Therefore, the same reference numerals are given to the same configurations, the description thereof will be omitted, and only the different points will be described.
In the first embodiment, the detection target portion 6 is provided outside the burner 3, but in the second embodiment, a part of the burner 3 is used as the detection target portion.

FIG. 3 is a cross-sectional view of the burner 3 according to the second embodiment. FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG.
As shown in FIGS. 3 and 4, the burner 3 of the present embodiment includes a plurality of tubular partition walls 11 to 14. A plurality of ports P1 to P4, which are flow paths for various gases, are formed by the plurality of partition walls 11 to 14. Each partition wall 11-14 extends along a common central axis O. In the present specification, the partition wall 11 located on the outermost circumference is referred to as the outermost partition wall.

The space between the outermost partition wall 11 and the partition wall 12 inside the outermost partition wall 11 is a combustion assisting gas port P1 to which the combustion assisting gas is supplied. The space between the partition wall 12 and the partition wall 13 is a flammable gas port P2 to which a flammable gas is supplied. The space between the partition wall 13 and the partition wall 14 is a seal gas port P3 to which the seal gas is supplied. The space inside the partition wall 14 located on the innermost side is a raw material gas port P4 to which the raw material gas is supplied. The outlet of the flammable gas port P2 is the spout 3a of the flammable gas.

The flammable gas port P2 is configured to selectively supply flammable gas and purge gas. When the supply of flammable gas to the flammable gas port P2 is stopped, purge gas is supplied to the flammable gas port P2, and the flammable gas in the flammable gas port P2 is pushed out to suppress flashback. ..
When the raw material gas is flammable, the raw material gas port P4 may also be configured so that the raw material gas and the purge gas are selectively supplied.

As shown in FIG. 4, in the present embodiment, the end portion of the partition wall 12 forming the flammable gas port P2 is located inside the end portion of the outermost partition wall 11 in the direction along the central axis O. .. In other words, the end portion of the outermost partition wall 11 projects to the + Y side of the combustible gas ejection port 3a in the direction along the central axis O.
In the present embodiment, the outermost partition wall 11 is a detection target portion whose temperature is measured by the temperature sensor 7. Further, a detection point 11b in which the temperature sensor 7 actually measures the temperature is located on the surface of the tip portion 11a, which is a portion of the detection target portion 11 that protrudes to the + Y side from the ejection port 3a.

As described above, also in the present embodiment, the detection target portion 11 projects from the ejection port 3a to the side (+ Y side) where the flammable gas is ejected in the direction along the central axis O of the ejection port 3a. With this configuration, when the pilot fire ignites the burner 3 due to the combustion of the flammable gas, the detection target portion 11 is quickly heated by the pilot fire. Therefore, by detecting the temperature of the detection target unit 11 with the temperature sensor 7, it is possible to accurately and quickly detect whether or not the pilot fire is ignited even when the thermal power of the pilot fire is small. ..

Further, in the present embodiment, the detection target portion 11 is compared with the case where the combustion assisting gas port P1 which is a port other than the flammable gas is located on the outermost circumference and the flammable gas port is located on the outermost circumference. Is hard to be heated by the pilot fire. Even in such a case, as shown in FIG. 4, by configuring the structure so that the structure is not arranged between the combustible gas ejection port 3a and the detection target portion 11, the detection target portion 11 is easily heated by the pilot fire. can do.

In FIG. 4, the tip of the partition wall 12 is located on the −Y side of the tips of the other partition walls 11, 13 and 14, but for example, only the outermost partition wall 11 which is the detection target portion is located on the other partition walls 12 to 14. It may be extended to the + Y side. Also in this case, the structure may not be arranged between the combustible gas ejection port 3a and the detection target portion 11.

Further, also in the present embodiment, by forming the outermost partition wall 11 which is the detection target portion from quartz, it is possible to suppress the deterioration of the quality of the porous glass fine particle body and the optical fiber base material.

The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

For example, in the first and second embodiments, the central axis O of the ejection port 3a extends along a substantially horizontal direction, but for example, the central axis O may be inclined with respect to the horizontal direction. Alternatively, the central axis O may extend parallel to the vertical direction. Even in these cases, the detection target portions 6 and 11 project from the ejection port 3a to the side where the flammable gas is ejected in the direction along the central axis O, so that the temperature sensor 7 determines whether or not the pilot fire is ignited. The accuracy can be improved.

Further, when the central axis O extends in a substantially horizontal direction or extends at an angle close to horizontal, the seed above the spout 3a is considered in consideration of the fact that the pilot fire 4 extends upward from the spout 3a. The detection target portion 6 may be provided only in the portion where the fire 4 hits. Further, although the detection target portion 6 of the first embodiment has a tubular shape, for example, a plate-shaped member arranged above the ejection port 3a may be used as the detection target portion 6. In this way, the shape and arrangement of the detection target portion 6 can be changed as appropriate.

Further, the structure of the burner 3 shown in the second embodiment is not limited to the structures of FIGS. 3 and 4, and can be changed as appropriate.
For example, the structure shown in FIGS. 5 and 6 may be adopted. In the examples of FIGS. 5 and 6, a partition wall 15 is further provided between the partition wall 11 and the partition wall 12. As shown in FIG. 6, a partition wall 15 (structure) is arranged between the ejection port 3a and the detection target portion 11, but the partition wall 15 does not project to the + Y side of the detection target portion 11. In this case as well, since the detection target portion 11 is directly heated by the pilot fire generated from the ejection port 3a, the presence or absence of the pilot fire can be detected by measuring the temperature of the detection target portion 11. That is, even if the structure is arranged between the ejection port 3a and the detection target portion 11, if the structure does not protrude from the detection target portion 11 to the side where the flammable gas is ejected, the second execution is performed. The same action and effect as the morphology can be obtained.

Further, the structure as shown in FIGS. 7 and 8 may be adopted. In the examples of FIGS. 7 and 8, a pipe 16 having an outer diameter smaller than the distance between the partition wall 11 and the partition wall 12 is arranged between the partition wall 11 and the partition wall 12. A plurality (four) of the pipes 16 are arranged at intervals in the circumferential direction. As shown in FIG. 8, a pipe 16 (structure) is arranged between the ejection port 3a and the outermost partition wall 11 which is a detection target portion, but the outer diameter of the pipe 16 is the partition wall 12 and the outermost partition wall 11. Since it is smaller than the distance between the pipe 16 and the pilot fire, the pilot fire generated from the spout 3a hits the detection target portion 11 so as to bypass the pipe 16. Therefore, the presence or absence of a pilot fire can be detected by measuring the temperature of the detection target unit 11. That is, even if the structure is located between the detection target portion 11 and the ejection port 3a, the outer diameter of the structure should be smaller than the distance between the partition wall 12 forming the ejection port 3a and the outermost partition wall 11. For example, the same effect as that of the second embodiment can be obtained.

Further, although the detection point 6b is located at the tip portion 6a of the detection target portion 6 in FIG. 2, the detection point 6b can be set to a portion other than the tip portion 6a. Also in this case, if the tip portion 6a is heated by the pilot fire 4 and the heat is transferred to the detection point 6b, the temperature of the detection point 6b is measured to detect whether or not the pilot fire 4 is ignited. be able to.
Similarly, in FIGS. 4, 6 and 8, the detection point 11b is located at the tip end portion 11a of the detection target portion 11, but the detection point 11b may be set at a portion other than the tip end portion 11a.

In addition, it is possible to replace the components in the above-described embodiment with well-known components as appropriate without departing from the spirit of the present invention, and the above-described embodiments and modifications may be appropriately combined.

For example, as the burner 3 in the first embodiment, the multi-tube structure described in the second embodiment may be adopted. That is, the detection target portion 6 as shown in FIG. 2 may be provided outside the burner 3 having the multi-tube structure as shown in FIG.

3 ... Burner 3a ... Ejection 6 ... Detection target 6a, 11a ... Tip 6b, 11b ... Detection point 7 ... Temperature sensor 9 ... Control unit 11-14 ... Partition 11 ... Outermost partition (detection target) 15, 16 … Structure 20… Light wave detector

Claims (9)

With a burner with a flammable gas outlet,
With a temperature sensor that can measure temperature,
A detection target unit whose temperature is measured by the temperature sensor is provided.
In the direction along the central axis of the spout, the detection target portion protrudes from the spout toward the side where the flammable gas is ejected .
The detection point of the detection target portion where the temperature sensor detects the temperature is a device for manufacturing a porous glass fine particle body, which is located at the tip end portion of the detection target portion. With a burner with a flammable gas outlet,
With a temperature sensor that can measure temperature,
A detection target unit whose temperature is measured by the temperature sensor is provided.
In the direction along the central axis of the spout, the detection target portion protrudes from the spout toward the side where the flammable gas is ejected.
The burner has a plurality of tubular bulkheads forming a plurality of ports.
The detection target portion is the outermost partition wall located on the outermost periphery of the plurality of partition walls.
Ports other than the flammable gas are located on the outermost circumference,
An apparatus for producing a porous glass fine particle body in which a structure is not arranged between the ejection port and the detection target portion. With a burner with a flammable gas outlet,
With a temperature sensor that can measure temperature,
A detection target unit whose temperature is measured by the temperature sensor is provided.
In the direction along the central axis of the spout, the detection target portion protrudes from the spout toward the side where the flammable gas is ejected.
The burner has a plurality of tubular bulkheads forming a plurality of ports.
The detection target portion is the outermost partition wall located on the outermost periphery of the plurality of partition walls.
Ports other than the flammable gas are located on the outermost circumference,
A device for producing porous glass fine particles, wherein a structure that does not project from the detection target portion to the side where the flammable gas is ejected is arranged between the ejection port and the detection target portion. With a burner with a flammable gas outlet,
With a temperature sensor that can measure temperature,
A detection target unit whose temperature is measured by the temperature sensor is provided.
In the direction along the central axis of the spout, the detection target portion protrudes from the spout toward the side where the flammable gas is ejected.
The burner has a plurality of tubular bulkheads forming a plurality of ports.
The detection target portion is the outermost partition wall located on the outermost periphery of the plurality of partition walls.
Ports other than the flammable gas are located on the outermost circumference,
A porous structure in which a structure is located between the detection target portion and the spout, and the outer diameter of the structure is smaller than the distance between the partition wall forming the spout and the outermost partition wall. Equipment for manufacturing fine glass particles. The central axis is not parallel to the vertical direction
The apparatus for producing porous glass fine particles according to any one of claims 1 to 4 , wherein at least a part of the detection target portion is located above the spout. The apparatus for producing porous glass fine particles according to any one of claims 1 to 5 , wherein the detection target portion is made of quartz. A light wave detection unit that detects a light wave generated by a pilot fire generated by burning the flammable gas, and a light wave detection unit.
Further provided is a control unit for determining whether or not the pilot fire is ignited based on both the measurement result of the temperature of the detection target unit by the temperature sensor and the detection result of the light wave by the light wave detection unit. , The apparatus for producing a porous glass fine particle body according to any one of claims 1 to 6. The porous glass fine particle body according to any one of claims 2 to 4 , wherein the detection point at which the temperature sensor detects the temperature of the detection target portion is located at the tip end portion of the detection target portion. manufacturing device. The process of ejecting flammable gas from the outlet of the flammable gas of the burner and igniting the flammable gas, and
By measuring the temperature of the detection target portion that protrudes from the spout to the side where the flammable gas is ejected in the direction along the central axis of the spout, the pilot fire generated by the combustion of the flammable gas. And the process of determining whether or not the gas is ignited
A step of supplying a raw material gas to the burner while the flammable gas is burning and adhering glass fine particles generated by reacting the raw material gas to a target member to obtain a porous glass fine particle body.
A method for producing an optical fiber base material, comprising a step of sintering the porous glass fine particles.

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