JPS593417B2 - Aluminum coated glass fiber manufacturing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for applying an aluminum coating around glass fibers.

In recent years, demand for aluminum-coated glass fibers has been increasing for use in radio wave communication devices, for example, due to the radio wave reflection properties of cloth-like bodies obtained using the aluminum-coated glass fibers. However, in order to apply an aluminum coating of about 5 μm around a glass fiber having a very small inner diameter of about 20 μm, from the viewpoint of strength, the glass fiber to be coated with aluminum must be melted without coming into contact with a solid element. It is required to pass through aluminum.

The object of this invention is to shape the tongue end of molten aluminum held in the furnace body based on the balance between gravity and electromagnetic force, and to pass glass fiber through this tongue end to form the glass fiber. It is an object of the present invention to provide a device that can move from above to below while contacting only molten aluminum.

? The illustrated embodiment will be specifically described below.

FIG. 1 shows the structure of the base body of the present invention. In FIG.
It forms b. 2 is a heat retention heater.

3 is molten aluminum and is held in the container 1 until a tongue 3a of molten aluminum can be formed at the opening 1b of the furnace body 1.

Reference numeral 4 denotes an induction coil, which includes the tongue end 3a of the molten aluminum, is arranged around the outer periphery of the molten aluminum 3 in the furnace body 1, and is supplied with alternating current power from an external power source (not shown).

This brings about an eddy current on the surface of the molten aluminum 3, and prevents the molten aluminum 3 from falling from the molten aluminum tongue end 3a based on the effect described later. Reference numeral 5 denotes a molten glass container, and the glass fiber 6 is drawn out from a nozzle 5a thereof, and is configured to be wound up by a winder 7 disposed below through a molten aluminum tongue end 3a.

In the above configuration, first, when high-frequency (for example, 1000 Hz) power is supplied to the induction coil 4, a magnetic flux is generated that interlinks with the induction coil 4. This magnetic flux acts on the molten aluminum 3, and the molten aluminum 3 is Eddy current is generated concentrically with the induction coil 4.

The eddy current generated in the molten aluminum 3 is shifted by 1800 degrees compared to the current flowing in the induction coil 4, that is, the current is in the opposite direction9, and is concentrated on the outer circumference of the surface of the molten aluminum 3 due to the effect of the skin effect. do. Therefore, repulsive forces act on the induction coil 4 and the molten aluminum tongue end 3a, so that the movable molten aluminum tongue end 3a is eventually pushed back into the furnace body 1. Due to the interaction between the electromagnetic force from the induction coil 4 and the gravity of the molten aluminum tongue end 3a, the tongue end 3a
maintains a state in which it slightly protrudes forward on the induction coil side at the opening 1b of the furnace body 1 for molten aluminum. Under this condition, the glass fibers 6 are passed through the molten aluminum tongue end 3a, whereby the glass fibers 6 are coated with aluminum and wound onto the winding drum 7. In this process, the glass fiber 6, which is lower temperature than the molten aluminum 3, always passes through the molten aluminum tongue end 3a, which causes a temperature drop. On the other hand, the molten aluminum tongue end 3a also causes a temperature rise due to electromagnetic induction.
The tongue end 3a, which is unstable in temperature, constantly undergoes reflux as shown by the arrow due to the electromagnetic repulsion with the induction coil 4. Exchange effects occur and the temperature instability associated with the above factors is reliably compensated for. FIG. 2 is a principle diagram showing one embodiment of the base invention, in which the cross-sectional center position P1 of the induction coil 4 is located at, for example, a position A, in the direction connecting the center of the molten aluminum tongue end 3a and the center of the furnace body 1. B is movably supported. On the other hand, the center position P2 of the furnace body 1 is movably supported between positions C and D parallel to the moving direction of the induction coil 4. In the furnace body 1, the level of molten aluminum held inside the furnace body 1 is E.
, F can be tilted. These movements and tilts may be performed by various well-known mechanisms such as hydraulic pressure (not shown) or manual operation of a handle using a screw mechanism. To give a specific example of the operation order in FIG. 2 above, first,
During the suspension of aluminum coating, the induction coil 4 is at point A, the furnace body 1 is at point D, and at the hot water level F by tilting control.

Next, the glass fiber 6 is passed through the nozzle 5a of the molten glass container 5.
When the induction coil 4 is derived, the induction coil 4 moves to the vicinity of point B, the furnace body 1 moves to the point C, and energization of the induction coil 4 is started. Thereafter, the furnace body 1 is tilted to regulate the molten metal level E. In this state, production of aluminum coated glass fibers is started. At this time, it is possible to finely adjust the position of the induction coil near point B while visually observing the state of the molten aluminum tongue end 3a. In addition, prior to maintenance, replacement, or suspension of operation of the furnace body refractory on the lower side of the molten aluminum tongue end 3a, the molten aluminum 3 held inside the furnace body 1 is tilted to the hot water level F, and the molten aluminum Measures such as preventing the tongue from flowing down from the tongue end 3a of No. 3 can also be taken.

FIG. 3 is a cross-sectional view of a main part showing another embodiment of the present invention, particularly regarding the cross-sectional shape of the induction coil 4. FIG.

In other words, as described above, the glass fibers 6 for aluminum coating that go downward from above penetrate through the molten aluminum 3, and do not come into contact with any other structure at the molten aluminum tongue end 3a.
Naturally, it is necessary to maintain the shape protruding to the side of the furnace body opening 1b. In order to generate such a shape using gravity, electromagnetic force, and the surface tension of the molten aluminum 3, it is necessary to devise a method for applying electromagnetic induction. For this purpose, the third
As shown in the figure, the lower section of the induction coil 4 is bent toward the furnace body 1. In addition, in Fig. 3 above, the induction coil 4 is shown as a one-turn coil that is water-cooled in the hollow part, but the number of turns is multiple turns, and the lower part of the entire cross section is the furnace body. It may also be curved in one direction.

Moreover, the glass fiber 6 for aluminum coating is not limited to the embodiment as long as it runs in a substantially vertical direction. FIG. 4 relates to an improvement of this specific invention, and is based on the configuration shown in FIG. 3, which relates to preventing the tip of the molten aluminum tongue end 3a from falling, and improves the engagement of the tongue end 3a with the glass fiber 6. In order to ensure this, the main part of the tongue end 3a is caused to protrude forward of the opening 1b. That is, the shielding ring 8 is installed opposite the forward protrusion of the tongue end 3a. This shielding ring 8 has one turn along the induction coil 4. This shielding ring 8 is caused by an induced current flowing through it to cause S based on electromagnetic induction from the induction coil 4 in this part to the molten aluminum 3 including the tongue end 3a.
Reduces magnetic flux. As a result, the electromagnetic induction effect disappears when the tongue end 3a protrudes toward the induction coil 4 side.
This is facilitated as the action of the outflow force of the molten aluminum 3 due to gravity is substantially strengthened. The material of the shielding ring 8 is preferably a low resistivity material that generates little heat due to induced current, and is preferably made of copper, for example. It goes without saying that this shielding ring 8 is attached so that it moves accordingly when the induction coil 4 moves as shown in FIG.

FIG. 5 relates to an improvement of the above-mentioned specific invention, in which means is added to prevent slag from flowing into the tongue end portion 3a of molten aluminum. It is provided near the tongue end 3a so as not to obstruct the passage of the tongue.

As a result, even if a flow of molten aluminum 3 occurs as the tongue end 3a is maintained, there is no room for the floated slag 10 to migrate to the tongue end 3a, which is the center of the aluminum coating action, and the glass fibers are The aluminum coating is well maintained. ? As mentioned above, the specific invention and the improved invention provide for the production of aluminum-coated glass fibers in which a portion of the glass fibers to be coated with aluminium, which runs in a substantially vertical direction, has a molten aluminum tip protruding in front of the opening of the furnace body. The means for arranging the parts is obtained through the mutual relationship between electromagnetic force and gravity.

Based on this configuration, even though the glass fibers drawn out from the molten glass container nozzle are extremely thin and weak in strength, they do not produce molten aluminum tip noise when coating. It has the advantage of being able to process without any contact with external solid materials.

[Brief explanation of drawings]

Figure 1 is a sectional view showing the configuration of the specific invention of this invention, Figure 2 is a sectional view showing the configuration of the specific invention of this invention.
The figure is a principle diagram showing a movable state, FIG. 3 is a sectional view of a main part showing one specific embodiment, and FIGS. 4 and 5 are sectional views of a main part showing an improved invention. 1...furnace body, 1b...opening, 3...
...molten aluminum, 4...induction coil, 6.
...Aluminium-coated glass fiber, 8...
...shielding ring, 9...shielding plate.

Claims (1)

[Claims] 1. A molten aluminum tongue end protruding in front of the opening of a furnace body for holding molten aluminum is disposed at a passage point of glass fibers to be coated with aluminium, which are traveling in the vertical direction. An apparatus for producing aluminum-coated glass fiber, characterized in that an induction coil is provided on the outer periphery of the furnace body, the induction coil surrounding the surface of the molten aluminum contained therein and preventing the molten aluminum from flowing out from the tongue end based on excitation. 2. The aluminum-coated glass fiber manufacturing apparatus according to claim 1, wherein the induction coil and the furnace body are movable in a horizontal direction connecting the center of the furnace body and the center of the tongue end. 3. The apparatus for producing aluminum-coated glass fiber according to claim 1, wherein the furnace body is tiltable in a direction in which the tongue end moves into the furnace body. 4. Claim 1, in which at least the portion of the induction coil facing the tongue end is bent toward the furnace body at the lower part of the cross section.
An apparatus for producing aluminum-coated glass fiber according to item 1 or 2 or 3. 5. A molten aluminum tongue protruding in front of the opening of the furnace body for holding molten aluminum is arranged at the passage point of the glass fiber to be coated with aluminium, which runs in the vertical direction, and the surface of the molten aluminum including the tongue is surrounded. An induction coil is provided on the outer periphery of the furnace body to prevent molten aluminum from flowing out from the tongue end based on excitation, and at least a portion of the induction coil facing the tongue end is bent toward the furnace body at a lower cross section, and the tongue A manufacturing device for aluminum-coated glass fiber in which a shielding ring is placed along the inner periphery of the induction coil at a height opposite to the tip of the end. 6 Claim 5 in which the induction coil and the furnace body are movable in the horizontal direction connecting the center of the furnace body and the center of the tongue end.
An apparatus for producing aluminum-coated glass fiber as described in 2. 7. The apparatus for producing aluminum-coated glass fiber according to claim 5, wherein the furnace body is tiltable in a direction in which the tongue end moves into the furnace body. 8 Claim 5 in which the shielding ring is made of copper material
An apparatus for producing aluminum-coated glass fiber according to item 6 or 7. 9 A molten aluminum tongue end projecting in front of the opening of the furnace body for holding molten aluminum is arranged at the passage point of the glass fiber for aluminum coating running in the vertical direction, and the surface part of the molten aluminum including the tongue end is surrounded. An induction coil is provided on the outer periphery of the furnace body to prevent molten aluminum from flowing out from the tongue end based on excitation, and the molten aluminum flows only below the surface of the molten aluminum in the furnace body near the opening of the furnace body. An apparatus for producing aluminum coated glass fiber, characterized by being equipped with a slag shielding plate. 10. The aluminum-coated glass fiber manufacturing apparatus according to claim 9, wherein the induction coil and the furnace body are movable in a horizontal direction connecting the center of the furnace body and the center of the tongue end. 11. The apparatus for producing aluminum-coated glass fiber according to claim 9, wherein the furnace body is tiltable in a direction in which the tongue end moves into the furnace body. 12. The apparatus for producing aluminum-coated glass fibers according to claim 9, 10, or 11, wherein at least the portion of the induction coil facing the tongue end is bent toward the furnace body at the lower portion of the cross section.