JPH0848534A - Capillary cutting device and capillary cutting method within double glass tubes - Google Patents

Abstract

PURPOSE:To mechanize production of double glass tubes by combining a gaseous mixture supply pipe, an oxygen supply pipe and a guiding member so as to provide a specific effect. CONSTITUTION:A connecting member 14 is arranged into a flat tube and, thereafter, a core end 3b projecting from this flat tube 5 is chucked by a core end chuck 17. At this time, the core end chuck 17 chucks only the core end 3b projecting from the flat tube 5. Both pipes 12, 13 are not chucked. In succession, a gaseous mixture composed of city gas a oxygen is supplied to the supply pipe 12 and is ejected out of its flame port 12a, and simultaneously, oxygen is ejected out of the oxygen supply pipe 12 to burn the gaseous mixture and to heat the point 3a to be melted and cut of the core 3. The point 3a to be melted and cut is cut by this heating. The point 3a to be melted and cut right after the cutting is continuously applied with the flame from the flame port 12a and, therefore, this part is rounded by this heating. This cutting method is applied for cutting the capillary in the double glass tubes, for example, the core tube (capillary), etc., arranged within the flat tube of a glass clinical thermometer, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin tube cutting device and a thin tube cutting method used for cutting thin tubes in a double glass tube, for example, a core (capillary tube) arranged inside a flat tube such as a glass thermometer. Regarding

[0002]

2. Description of the Related Art Generally, a glass tube having a double tube structure includes, for example, a glass thermometer, a discharge lamp and a vacuum tube. For example, a platinum wire heater or the like is usually used as a device for cutting a capillary tube such as a glass thermometer, that is, a core.

As shown in FIG. 7, this platinum wire heater 70
Is a handle 71 made of an insulating material for a worker to hold.
It is composed of two conducting wires 72 held in parallel to the handle portion 71 with a predetermined width, and a platinum wire 73, etc., which are arranged substantially at the tips of these two conducting wires 72 and generate heat at a high temperature when energized. There is. The predetermined width is such a width that the two conducting wires 72 can be inserted into the glass flat tube of the glass thermometer.

In the core cutting process of this glass thermometer, as shown in FIG. 8, an operator holds the handle portion 71 by hand and the platinum wire 7
3 is inserted to the cutting point 76a of the core 76 in the flat tube 75,
By energizing the two conducting wires 72, the core 76 is melted and, as a result, as shown in FIG. 9, the core 76 in the flat tube 75 of the glass thermometer is cut at a predetermined position and the core cutting step is completed. .

By the way, in recent years, in the manufacturing process of glass thermometers, mechanization of each process has been promoted for the purpose of improving mass productivity.

However, in the platinum wire heater 70, since the platinum wire 73 is thin, a failure occurs during the work, that is, a breakage of the platinum wire 73 occurs frequently, and the operation is interrupted due to this failure. Was difficult. At present, the platinum wire 73 has to be thin in order to increase the heating temperature and reduce the required current. Further, in the platinum wire 73, since the heating range of the core 76 is narrow, the fusing point is squared, and after the fusing, a work step of further rounding the head of the core 76 with the platinum wire 73 is required. This work is very fine and difficult to mechanize.

[0007]

As described above, in the conventional thin tube cutting device, since platinum wire is used, a failure such as disconnection frequently occurs, and the head is rounded after cutting the core. However, there is a problem that it is difficult to mechanize.

The present invention has been made in order to solve such a problem, and the process of manufacturing a double glass tube can be mechanized by cutting a core, that is, a thin tube without using a platinum wire or the like. An object of the present invention is to provide a thin tube cutting device in a double glass tube and a thin tube cutting method.

[0009]

In order to achieve the above-mentioned object, the thin tube cutting device for a double glass tube according to the present invention is used in a cutting step for cutting a thin tube arranged in the glass tube. In the thin tube cutting device, which has a flame port toward the thin tube at one end, a mixed gas supply pipe for heating the thin tube by jetting a mixed gas of gaseous fuel and oxygen from the flame port into the glass tube, An oxygen supply pipe, which is arranged so as to face the mixed gas supply pipe through the narrow pipe and has an opening for supplying oxygen to the mixed gas ejected from the flame port of the mixed gas supply pipe, and the both supply pipes. And a guide member for arranging the flame port of the mixed gas supply pipe at a predetermined cut portion of the thin tube inside the glass tube while supporting at a space allowing insertion into the glass tube.

The thin tube cutting device in the double glass tube according to the second aspect of the present invention is the thin tube cutting device according to the first aspect,
The opening of the oxygen supply pipe is arranged so as to eject oxygen perpendicularly to the combustion direction of the mixed gas that heats the cut portion of the thin pipe.

According to a third aspect of the present invention, there is provided a thin tube cutting method for cutting a thin tube arranged in a glass tube, wherein an opening of an oxygen supply pipe and a mixed gas are provided in a cutting portion of the thin tube inside the glass tube. Arranging the flame outlet of the supply pipe,
After arranging the both supply pipes, a step of chucking one end of the thin tube protruding to the outside of the glass pipe with a core end chuck, and ejecting a mixed gas of gaseous fuel and oxygen from a flame port of the mixed gas supply pipe, A step of heating the cutting portion by injecting oxygen from the opening of the oxygen supply pipe to burn a mixed gas, and a step of pulling the core end chuck to cut the cutting portion when the cutting portion is softened by heating. And a step of discharging the combustion gas to the outside of the glass tube by heating the thin tube cutting portion by the combustion flame of the mixed gas and ejecting oxygen from the oxygen supply tube.

[0012]

In the inventions of claims 1 and 3, the thin tube is cut by burning gas instead of the conventional platinum wire heater.

In this case, first, the guide member is inserted into the glass tube, and the flame port of the mixed gas supply tube and the oxygen supply opening are arranged at the cut portion of the thin tube.

Before heating the thin tube, one end of the thin tube protruding outside the glass tube is chucked by the core end chuck. Next, a mixed gas of gaseous fuel and oxygen is ejected from the flame port and burned to heat the cut portion to soften it. When the cutting portion is softened, the core end chuck is pulled to cut the thin tube from the cutting portion. Also at this time, since oxygen is jetted from the oxygen supply pipe into the glass tube, the combustion gas obtained by burning the mixed gas is discharged to the outside of the glass tube. Immediately after cutting the thin tube, the cut portion is rounded by heating the flame from the flame mouth.

Further, by ejecting oxygen into the glass tube by the oxygen supply tube, the oxygen filled in the glass tube stabilizes gas combustion, and carbon residue due to incomplete combustion disappears.

As a result, mechanization of the center cutting process can be realized.

According to the second aspect of the present invention, the opening of the oxygen supply pipe is provided so that oxygen is jetted at right angles to the combustion flame of the mixed gas that heats the cut portion of the thin tube. Since the combustion flame is blown away by the jetted oxygen and the direction of the flame is changed, the combustion flame does not hit the glass tube and deterioration of the glass tube, for example, cracks can be prevented.

[0018]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a diagram showing the structure of a core-cutting burner for a thermometer having a glass double tube structure according to a first embodiment of the thin tube cutting device for glass double tubes of the present invention, and FIG. It is a cross-section part which shows a front-end | tip part.

In FIGS. 1 and 2, 11 is a burner. The burner 11 is a supply pipe (mixed gas supply pipe) for a mixed gas of gaseous fuel such as propane gas and oxygen.
12, an oxygen-only supply pipe (oxygen supply pipe) 13, a connecting member 14 as a guide member for holding both supply pipes 12 and 13 substantially in parallel, and for supplying each gas to each supply pipe 12 and 13. The pipe joint 16 and the like. The connecting member 14 is formed in a cylindrical shape so that the inside is hollow, and the core 3 as a thin tube is inserted therein.

Each tip 12b, 1 of each supply pipe 12, 13
3a is obliquely cut so as to facilitate insertion into the flat tube 5, and is provided with a slope. The tip portion 12b of the mixed gas supply pipe 12 is closed by silver brazing or the like. Further, a flame port 12a is provided on the side of the tip end portion 12b of the mixed gas supply pipe 12 facing the core 3 slightly on the front side. The mixed gas is ejected from the flame port 12a in a direction crossing the tube axis. Further, the tip portion 13a of the oxygen supply pipe 13 is
The opening remains as it is cut diagonally.

Both supply pipes 12 and 13 are supported by a connecting member 14 so as to be positioned on both sides of the core 3 when inserted into the glass flat pipe 5 of the thermometer. The connecting member 14 and the supply pipes 12 and 13 are integrated by silver brazing or the like. Openings 14a are provided on both sides of the connecting member 14 so as not to interfere with the combustion of the mixed gas. Further, a slit 14b is provided at the mounting portion of the oxygen supply pipe 13 so as to supply oxygen into and out of the connecting member 14, and the oxygen supply pipe 13 is mounted so as to enter the slit 14b.

Next, referring to FIGS. 3 to 5, the burner 1 will be described.
The operation of No. 1 will be described.

In the manufacturing process of the glass thermometer, in the core cutting process, the flat tube 5 is supplied with the core 3 (capillary tube) protruding from one end thereof and mercury or the like injected into the core 3.

In this case, first, as shown in FIG. 3, while the core 3 is being inserted through the connecting member 14 of the burner 11, the connecting member 14 is inserted into the flat tube 5, and B- in FIG.
As shown in FIG. 4 which is a B ′ cross section, inside the flat tube 5, the flame port 12 a of the mixed gas supply tube 12 and the opening of the oxygen supply tube 13 are located at the melting cutting point 3 a as the fusing part of the core 3. It is inserted until.

After the connecting member 14 is placed in the flat tube 5, the core end portion 3b protruding from the flat tube 5 is chucked by the core end chuck 17, as shown in FIG. At this time, the core end chuck 17 chucks only the core end portion 3b protruding from the flat tube 5, and does not chuck both tubes 12 and 13. At this time, the core end 3b is chucked by the core end chuck 17 until the core cullet (unnecessary portion cut) is discharged from the flat tube 5 after chucking.

Then, a mixed gas of gas and oxygen is supplied to the supply pipe 12 and ejected from the flame port 12a,
Oxygen is jetted from the oxygen supply pipe 13 to burn the mixed gas and heat the melting cutting point 3a of the core 3.

When the melting cutting point 3a is softened by this heating, the core end chuck 17 is pulled to cut the melting cutting point 3a. Immediately after the cutting, the melt cutting portion 3a is rounded by the heating because the flame from the flame port 12a is continuously applied.

Further, since oxygen is jetted from the oxygen supply pipe 13 into the flat pipe 5, the flat pipe 5 is filled with oxygen, gas combustion is stabilized, and carbon residue due to incomplete combustion does not occur. The combustion gas is efficiently discharged to the outside of the flat tube 5.

Further, during heating of the core 3, oxygen is ejected from the oxygen supply pipe 13, so that the combustion flame is blown off in the axial direction of the flat pipe 5 before hitting the flat pipe 5, so that the flat pipe 5 The combustion flame does not hit, and deterioration of the flat tube 5, for example, cracks can be prevented.

Thus, according to the burner of the first embodiment,
The core cutting (melt cutting) of the core 3 is performed from the platinum wire heater to the burner 11
By changing to, the operation required for fusing the core 3 becomes a simple operation of only the chucking operation and the pulling operation, and the work of rounding the corners of the melting cutting point 3a is performed by the burner 11
Since it is possible to perform only the work of taking out the core 3 while continuing the combustion of No. 3 and the series of operations (melt cutting) can be continuously performed, it is possible to mechanize the core cutting process from manual work.
In addition, by mechanizing this process, the operating rate can be improved.

In addition to the mixed gas supply pipe 12, the oxygen supply pipe 13 for supplying only oxygen is installed at the melting and cutting point 3a to ensure the supply of oxygen, improve the combustion efficiency of the burner, and burn the mixed gas. It became stable.
Further, since the oxygen amount inside the flat tube 5 is increased by the oxygen supply tube 13 and the mixed gas jetted therein is completely combusted, black stain is not generated at the melt cutting portion 3a of the core.
Further, the combustion flame jumping out from the opening 14a of the cylindrical connecting member 14 is blown off in the axial direction of the flat tube 5 by the oxygen ejected from the oxygen supply tube 13, so that it does not touch the facing surface of the flat tube 5 and the flat tube made of glass. 5 is no longer damaged.

Although propane gas was used as the gaseous fuel in this embodiment, methane gas, butane gas, hydrogen gas, etc. can also be used.

Next, the burner of the second embodiment according to the present invention will be explained with reference to FIG.

FIG. 6 is a view showing an example of a burner using an improved connecting member in which the connecting member of the first embodiment has a simplified and downsized shape.

As shown in the figure, the connecting member 61 of this burner has a streamlined shape with a rounded tip portion 61a.

In the case of this burner, since the tip portion 61a has a round streamlined shape, the burner can be easily and surely inserted into the flat tube. The combustion efficiency of the burner does not deteriorate under the influence of this shape.

According to the burner of the second embodiment, since the tip end portion 61a of the connecting member 61 has a rounded streamlined shape, the burner can be easily and surely inserted into the flat tube. became.

Although not shown, in a glass thermometer using a relatively large glass tube, the number of gas-oxygen mixed gas supply pipes 12 and oxygen supply pipes 13 is increased to make a plurality of flame openings 12a. Core cutting by doing (melt cutting of core)
It is possible to improve the quality and shorten the melt cutting time.

In addition to the thermometer having the double glass tube structure of the embodiment, the present invention can be applied to melt-cut the inner tubes of electron tubes such as discharge lamps and vacuum tubes.

[0041]

As described above, according to the present invention, the guide member for supporting the mixed gas supply pipe and the oxygen supply pipe is inserted into the glass tube, and the flame of the mixed gas supply tube is inserted into the thin tube cutting portion in the glass tube. By arranging the mouth, softening the cutting part by combustion of the mixed gas ejected from it, by pulling the thin tube from the outside and continuing the combustion of the mixed gas while cutting, the head is rounded, Since the step of rounding the head after cutting the core is unnecessary and the series of operations described above can be continuously performed, the step of manufacturing the double glass tube can be mechanized.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a core cutting burner of a glass thermometer according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the tip of the burner shown in FIG.

FIG. 3 is a diagram showing a state in which the burner of FIG. 1 is inserted into a flat tube of a glass thermometer.

FIG. 4 is a cross-sectional view taken along the line BB ′ of FIG. 3, and is a view showing a melt cutting point 3a of the core.

FIG. 5 is a cross-sectional view showing a state in which part A in FIG. 3 is chucked by a core end chuck.

FIG. 6 is a view showing a simplified burner connecting member as a modified example of the invention.

FIG. 7 is a view showing a platinum wire heater as a conventional capillary cutting device in a double glass tube.

FIG. 8 is a diagram showing a state in which the core of the glass thermometer is cut using the platinum wire heater of FIG.

9 is a diagram showing the glass thermometer after cutting the core using the platinum wire heater of FIG. 7. FIG.

[Explanation of symbols]

3 ... Core (narrow tube), 3a ... Melt cutting point of core, 5 ... Flat tube (glass tube), 11 ... Burner, 12 ... Mixed gas supply tube,
12a ... Flame port, 12b ... Tip of mixed gas supply pipe, 13
... Oxygen supply pipe, 13a ... Tip (opening) of the oxygen supply pipe,
14, 61 ... Connecting member, 14a ... Opening of connecting member, 1
4b ... Slit, 16 ... Pipe joint, 61a ... Tip of connecting member.

Claims (3)

[Claims] 1. A thin tube cutting device used in a cutting step for cutting a thin tube arranged in a glass tube, wherein a gas port directed to the thin tube is provided at one end, and the gas fuel is introduced into the glass tube through the flame port. A mixed gas supply pipe that heats the thin tube by jetting a mixed gas of oxygen and oxygen, and a mixture that is arranged so as to face the mixed gas supply pipe through the thin tube and that is jetted from the flame port of the mixed gas supply pipe. An oxygen supply pipe having an opening for supplying oxygen to the gas, and the flame outlet of the mixed gas supply pipe while supporting the both supply pipes at an interval that can be inserted into the glass pipe inside the glass pipe. A thin tube cutting device in a double glass tube, comprising: a guide member arranged at a predetermined cutting portion of the thin tube. 2. The thin tube cutting device according to claim 1, wherein the opening of the oxygen supply pipe is arranged so as to eject oxygen in a direction orthogonal to the combustion direction of the mixed gas that heats the cutting portion of the thin tube. Capillary cutting device characterized by being. 3. A thin tube cutting method for cutting a thin tube arranged in a glass tube, the step of arranging an opening of an oxygen supply tube and a flame port of a mixed gas supply tube in a cutting portion of the thin tube inside the glass tube. A step of chucking one end of the thin tube protruding to the outside of the glass tube with a core end chuck after arranging the both supply tubes, and ejecting a mixed gas of gaseous fuel and oxygen from a flame port of the mixed gas supply tube. A step of heating the cut portion by injecting oxygen from the opening of the oxygen supply pipe to burn a mixed gas, and pulling the core end chuck to cut the cut portion when the cut portion is softened by heating And a step of discharging combustion gas to the outside of the glass tube by ejecting oxygen from the oxygen supply tube while heating the thin tube cutting portion by the combustion flame of the mixed gas. Capillary cutting wherein.