JPH09263414A - Method for forming fused grass and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain glass gob and glass lens having the outside diameter (>=11mm diameter) of a large forming surface having no stepped grooves. SOLUTION: A rotary disk 20 is disposed and a forming die 12 is mounted turnably in the position apart by a distance below the radius of the forming die 12 from the revolving shaft 18 of the rotary disk 20 in the method and device for obtaining formed parts 19 by dropping the glass 2 fused in a fusing crucible 1 onto the forming die 12 and transferring the die shape to the glass. The chordally wound springs fixed to the outer periphery of the forming die 12 are connected to a base disk 17 and are pulled by a basket 16 to cause the translational rotation to rotate the position of the forming die without changing the posture and direction of the forming die by rotation of the rotary disk. The glass viscosity is <=25 poises before 0.2sec after the glass liquid drop 14 falls onto the forming die 12. The glass liquid drop 14 does not harden until the drop spreads on the forming surface 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molten glass forming method and apparatus for producing glass gobs from molten glass.

[0002]

2. Description of the Related Art Conventionally, a method for producing a glass gob from a molten glass by molding a glass having a medium diameter or more includes heating and melting the glass in a melting crucible, and supplying the molten glass by dropping onto a molding die or a supporting member. A method for molding glass in which the mold shape is transferred to the glass after accumulating and accumulating is disclosed in JP-A-6-20.
No. 6730 is proposed. Further, in the above-mentioned JP-A-6-206730, as an apparatus for producing a glass gob from molten glass, a supply nozzle is connected to the bottom of a melting crucible, and a melting crucible and a heater for individually heating the supply nozzle are provided, There is described an apparatus for supplying and stopping molten glass by heating a supply nozzle, and dropping and supplying the molten glass to a molding die or a supporting member installed below the supply nozzle.

[0003]

However, in the method and apparatus proposed above, as shown in FIG. 5, after the glass droplet 5 is dropped on the mold 9 or the supporting member, the glass droplet 5 is rapidly held during the stay. Is absorbed in heat by the molding die 9 or the supporting member and is cooled and hardened.
Alternatively, even if the initial contact surface with the support member forms the cured film 6 first and then the mold contact surface (molding surface) of the glass droplet 5 is expanded by adding or pressing the glass droplet 5. A deep step groove 7 is formed at the boundary between the initial contact surface and the enlarged new surface, and the outer diameter (φ
It was difficult to obtain a glass gob having a size of 11 mm or more).

The present invention has been made in view of the above problems of the prior art. The invention of claim 1 can obtain a glass gob having a large molding surface outer diameter (φ 11 mm or more) without a step groove. Another object of the present invention is to provide a molten glass capable of forming a glass gob having a large molding surface outer diameter (φ 11 mm or more) without a step groove. It is an object of the present invention to provide a molding apparatus for molten glass which has no step groove and which can adjust the outer diameter and the inner wall of the molded product.

[0005]

According to the invention of claim 1, 1.4 g of molten glass (OHARA BAL41) heated and melted at 1300 ° C. is dropped on a molding die (heat-retained at 440 ° C.), When the temperature of the lower surface of the glass droplets in contact with the mold was measured, the result was as shown in FIG. According to this, in order for the molten glass to be fused and deformed by its own weight and surface tension to obtain a glass viscosity of 25 poise or less, it is necessary to be within 0.2 sec after the mold contact (the temperature of the glass droplet is 1200 ° C. or more). I understand. If this condition is satisfied, it is possible to fuse the initial contact surface and the enlarged surface expanded by impact before a cured film is formed on the initial contact surface between the glass droplet and the mold.

In order to realize the enlarged deformation of the outer diameter of the molding surface within the above 0.2 sec, the translational rotation (3) in which the position of the molding die is rotated in advance without changing the posture and direction of the molding die.
(00 to 1800 rpm), the molten glass droplets were dropped onto the molding die, and the outer diameter of the molding surface of the glass droplets could be enlarged within 0.2 sec after the dropping.

After the glass droplets come into contact with the surface of the mold, the action of enlarging the outer diameter of the molding surface rapidly progresses, and before the hardening of the glass droplets progresses within 0.2 sec (with a glass viscosity of 25 poise or less). Since the action of expanding the surface can be completed, it is possible to obtain a glass gob having a large molding surface outer diameter without step grooves.

According to a second aspect of the present invention, a rotary disk is rotatably provided on the base, and the mold is rotatably mounted at a position separated from the rotary shaft of the rotary disk by a distance equal to or smaller than the radius of the mold. The mold is circularly moved by rotating the mold with a diameter equal to or smaller than its radius. As a result, overlapping points of the mold surface are generated during the rotation of the mold, and a point at which the glass liquid can be constantly dropped is obtained. At this time, in order to maintain the posture of the molding die constant, a spiral spring is connected to a position of one or more of the outer periphery of the molding die or the die holder and pulled,
Suppress the type of rotation. As described above, the rotation of the rotary disk allows the mold to be translated and rotated, so that the outer diameter of the glass-melted droplets dropped on the mold can be rapidly expanded, thereby suppressing the formation of a step.

According to a third aspect of the present invention, a rotary disk is rotatably provided on the base, one end of the arm is rotatably fixed at a position distant from the rotation axis of the rotary disk, and one end of the arm is circularly moved. A mold is fixed to the other end of the arm, and the intermediate part of the arm is slidably held and held by a rotatable rotation member to rotate the mold in translation. be able to. As a result, the outer diameter of the glass melt droplets dropped on the molding die can be rapidly expanded, and the generation of steps is suppressed.

According to a fourth aspect of the present invention, a bearing is mounted on the outer periphery of a cylindrical eccentric cam having an eccentric rotation shaft, and the rotation motion can be canceled by using only the eccentric circular motion of the cam. A bucket for holding the outer periphery of the bearing and the molding die concentrically is provided, and a spiral spring is connected to and pulled at a position of at least one end of the outer periphery of the bucket to cancel the rotation. As a result, the eccentric cam is eccentrically moved circularly by the rotation of the rotary shaft, the rotation of the cam is canceled, the molding die can rotate in translation, and the outer diameter of the molten glass droplet dropped on the die can be quickly increased. To be able to expand,
Suppress the generation of steps.

According to a fifth aspect of the present invention, in a method for forming a molten glass in which molten glass is dropped onto a molding die and the shape of the glass is transferred to the molding die, the function of adjusting the outer diameter and the inner wall of the molding surface of the molded product is adjusted. This is a molding method proposed to realize the method, in which molten glass droplets are dropped onto a translationally rotating mold and the amplitude and rotation speed of the translational rotation are adjusted to change the outer diameter and medium thickness of the molded product. Can be made.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment of the Invention] A first embodiment of the present invention will be described with reference to FIG. There is glass (glass material, OHARA.BAL41) in the melting crucible 1, and it can be heated and melted at 1000 ° C. to 1400 ° C. by the crucible heater 3 on the outer periphery of the melting crucible 1. A supply nozzle 4 is connected to the bottom of the melting crucible 1 and can be heated to 1200 ° C. to 1300 ° C. by a nozzle heater 10 provided on the outer periphery of the supply nozzle 4. Further, a plunger 11 for opening and closing the supply nozzle 4 is inserted into the melting crucible 1 so as to be freely inserted into and removed from the melting crucible 1, and the glass 2 after melting may flow out from the tip of the supply nozzle 4. At this time, the molten glass 2 can be stopped from flowing out and the number of drops at the time of dropping can be adjusted. The glass 2 after melting tends to flow out from the tip of the supply nozzle 4, but the flow is stopped and the number of drops at the time of dropping can be adjusted by a plunger 11 that is inserted into the melting crucible 1 so as to be freely inserted and removed. .

A mold 12 is installed below the supply nozzle 4, and a mold heater 13 is provided on the outer periphery of the mold 12 so that the mold temperature is 380 ° C.
The mold 12 and the mold heater 13 are heated and kept at a temperature of up to 480 ° C., and are held and inserted in the bucket 16.

On the other hand, a rotary shaft 18 which is rotated by a rotary drive unit (not shown) is rotatably fixed to the concave base 17, and a rotary plate 20 fixed to the rotary shaft 18 is rotatable. An eccentric shaft 20 'is fixed at a position apart (eccentric) from the rotary shaft 18 of the rotary plate 20.
The bucket 16 is rotatably connected to the front end of 0 'so that the distance between the rotating shaft 18 and the eccentric shaft 20' is less than the radius of the forming die 12.

Further, a spiral spring 21 is fixed at one or more positions on the outer circumference of the bucket 16, and the bucket 16 is pulled by the spiral spring 21 and fixed to the base 17.

A melting crucible provided in the molding apparatus having the above-mentioned structure
1, supply nozzle 4, plunger 11 are made of platinum,
The heater 3 is a molybdenum disilicide sintered wire heater.
The trick heater 10 is a high-frequency heater and a mold heater 13.
Is a metal resistance wire heater, and the mold 12 is made of WC alloy.
Chromium nitride film on the surface or Cr on alumina
_TwoO_ThreeWas used. Alumina base material
When using the mold of 60 ° C to 100 ° C lower than the mold temperature above
If the mold temperature is not high, the heat retention is high and the glass burns off
Disappears.

Next, the molding of molten glass using the molding apparatus having the above-mentioned structure will be described together with its operation. Glass 2 (OHARA / BAL41) is put into the melting crucible 1 and the melting crucible 1 is heated to 1000 ° C to 1400 ° C by the crucible heater 3.
It is heated to melt the glass 2 inside. During the melting, the glass that enters the inside is cooled and hardened without heating the supply nozzle 4, and the glass is prevented from flowing out. This allows the molten glass to be agitated during that time. After the heating and melting of the glass 2 is completed, the plunger 11 is inserted and the upper end of the supply nozzle 4 is plugged, and the supply nozzle 4 is heated to 1200 ° C. to 1300 ° C. by the nozzle heater 10 to melt the excess glass inside to a low viscosity. And then discharge. The molding die 12 is heated by a die heater 13 at a die surface temperature of 380 ° C. to 4 ° C.
It is heated to 80 ° C. (a mold temperature range where wrinkles do not occur on the molding surface and seizure does not occur). Further, the rotary shaft 18 and the rotary plate 20 are rotated by a rotary drive unit (not shown) to rotate the eccentric shaft 2
0'is circularly moved about the rotation axis 18. At this time, in order to suppress the rotation of the molding die 12 and maintain the posture thereof, the molding die 12 and the bucket 16 are pulled by a coiled spring 21 connected to the outer circumference of the bucket 11 in which the molding die 12 is housed.
Does not rotate about the eccentric shaft 20 ′, and does not change the posture and direction of the mold 12 and does not rotate about the rotary shaft 18.
Translation is a circular motion that changes the position of.

Next, the plunger 11 is moved up and down to drop a required amount (for example, 1.4 g) of glass droplets 14 onto the molding die 12 installed below. At this time, the glass droplet 14
Is supplied onto the mold 12 during translational rotation, and is quickly (0.
It flows within 2 seconds) and the outer diameter expands.

According to the first embodiment of the present invention, the molding die 12
Before the glass surface of the glass droplet 14 that has dropped onto the mold forms a cured film on the initial contact surface by cooling due to heat conduction to the mold 12 (before 0.2 seconds after contact, glass temperature 1200 ° C. or higher, glass viscosity 25 poise or less). ), The expansion is completed, so there is no expansion surface (after the glass drop molding surface cools and the glass viscosity becomes 25 poise or more) 0.2 seconds after the contact, so that there is no expansion surface between the initial contact surface and the expansion surface. The outer diameter of the large molding surface (φ1
It is possible to obtain a molded glass product 19 having a size of 1 mm or more).

[Second Embodiment of the Invention] A second embodiment of the present invention will be described with reference to FIG. Molten crucible 1, glass 2, crucible heater 3, supply nozzle 4, nozzle heater 10, mold 12, mold heater 13, plunger 11, glass droplet 14, molded product 19, bucket provided in the molding apparatus of this embodiment. The arrangement and configuration of 16 are the same as those in the first embodiment.
Is the same as

In addition to the above, the molding apparatus of this embodiment has a rotation center shaft 2 rotatable by a rotation drive mechanism (not shown).
4 and the rotating disk 22 are arranged below the supply nozzle 4 from the arm 23.
Are rotatably fixed on the base 25 at positions separated by the length. One end of an arm 23 is rotatably fixed to a circular movement shaft 26 at a position distant from a rotation center shaft 24 on a rotary disk 22, and a bucket 16 containing a mold 12 is rotated at the other end of the arm 23. It is fixedly immovable. A sliding / rotating member 31 that holds the arm 23 slidably and is rotatable with respect to the base 25 is fixed to the base 25 in the middle of the arm 23. At this time, the center of the translational rotation of the molding die 12 is arranged directly below the supply nozzle 4.

Next, the operation of the second embodiment will be described.
The operation up to melting and dropping of the glass 2 is the same as that of the first embodiment, and therefore its explanation is omitted. When the rotation center shaft 24 and the rotary disk 22 are rotated by a rotation drive mechanism (not shown), the circular motion shaft 26 circularly moves together with the left end of the arm 23. At this time, the middle part of the arm 23 is restricted by the sliding / rotating member 31 into left and right reciprocating motions and horizontal angular reciprocating motions, so that the circular motion of the circular motion shaft 26 is fixed to the right end of the arm 23. The bucket 16 and the molding die 12 that have been formed can be translated and rotated.

According to the second embodiment of the present invention, the molding die 12 is used.
Of the glass droplet 14 is supplied to the molding die 12 by cooling by heat conduction to the forming die 12 before forming a cured film on the initial contact surface (after contact). Before 0.2 sec, the outside diameter can be expanded to a glass temperature of 1200 ° C or more and a glass viscosity of 25 poise or less), there is no surface to expand 0.2 seconds after contact, and there is also a step groove formed between the initial contact surface and the expansion surface. It is possible to obtain a glass molded product 19 having a large molding surface outer diameter (φ11 mm or more) that does not occur and has no step groove. Further, in the present embodiment, since the rotary disk 22 is not directly below the molding die 12, there is an advantage that the amplitude of translational rotation can be easily adjusted. Further, the amplitude can be adjusted between molding cycles.

[Third Embodiment of the Invention] A third embodiment of the present invention will be described with reference to FIG. Molten crucible 1, glass 2, crucible heater 3, supply nozzle 4, nozzle heater 10, molding die 12, mold heater 13, plunger 11, glass droplet 14, molded product 19, string winding provided in the molding apparatus of this embodiment. The arrangement and configuration of the spring 21 and the base 17 are the same as those in the first embodiment.

In addition to the above, the molding apparatus of this embodiment is provided with a bucket holder 27 which contains a molding die 12 and a die heater 13 on the outer periphery thereof, and at the lower part of which a bearing 28 is enclosed and which is formed with vertical recesses. Has been. on the other hand,
The base 17 is provided with a rotary shaft 30 rotatably fixed by the rotation of a rotary drive unit (not shown).
0 is connected and fixed at a position away from the center of the circle of the cylindrical eccentric cam 29. The eccentric cam 29 is fitted and inserted into the inner diameter of the bearing 28 included in the lower portion of the bucket holder 27, and rotatably holds the bucket holder 27. Further, the bucket holder 27 is the first embodiment.
Similarly, the coiled spring 21 is fixed to one or more points on the outer periphery thereof, and the coiled spring 21 is stretched and fixed to the base 17 by the coiled spring 21.

Next, the operation of the present embodiment will be described. The operation up to melting and dropping of the glass 2 is the same as that of the first embodiment, and therefore its explanation is omitted. When the rotating shaft 30 and the eccentric cam 29 are rotated by a rotation drive mechanism (not shown), the outer diameter circle of the eccentric cam 29 is eccentrically moved circularly. At this time, in order to take out only the circular motion of the eccentric cam 29 and prevent the rotation of the rotation from being transmitted to the bucket holder 27 and the molding die 12, the bearing 28 is interposed between the eccentric cam 29 and the bucket holder 27, and the outer circumference of the bucket holder 27 is The spiral spring 21 is pulled and fixed to the base 17 to stop rotation.

According to the third embodiment of the present invention, the molding die 12 is used.
And the glass surface after the glass droplets 14 are supplied to the mold 12 is cooled by heat conduction to the mold 12 to form a cured film on the initial contact surface. The outer diameter expansion can be completed before
It is possible to obtain a glass molded product 19 having a large molding surface outer diameter (φ 11 mm or more) without a step groove. Further, in the present embodiment, the position of the rotary shaft 30 is set to the supply nozzle 10.
It is only necessary to set the position directly under the position, and it is possible to easily set the position, and there is an advantage that the structure is simple, there are few failures, and it is compact.

[Fourth Embodiment of the Invention] A fourth embodiment of the present invention will be described with reference to FIGS. In this embodiment,
It is a method of molding molten glass with a molding device having the configuration used in prison sentences 1, 2, and 3, respectively.

After the mold 12 is translated and rotated, molten glass is dropped onto the mold 12 to rapidly expand the outer diameter of the molded product 19. The larger the translational rotation amplitude, the larger the diameter expansion. The inner wall becomes thinner and the outer diameter can be increased more rapidly and more evenly as the number of revolutions increases, and at the same time, the inner diameter becomes larger and the inner wall becomes thinner. In other words, the diameter and the inside thickness can be adjusted by adjusting the amplitude and the rotation speed.

However, since the glass droplet 14 must hit the forming die 12, it is appropriate that the amplitude be suppressed to 1/4 or less of the diameter of the forming die 12. In addition, the number of revolutions is 0.2 sec or less and one revolution or more must be performed, so at least 300 rpm is required. The rotation speed can be adjusted by adjusting the output of a rotary drive mechanism not shown in FIGS. On the other hand, in the adjustment of the amplitude, in FIG. 2 (Embodiment 1), the eccentric shaft 21 is exchanged with another one having a different mounting position to the rotary plate 20, or a large number of mounting positions are prepared on the rotary plate 20, and the assembly is performed again. adjust. Furthermore, in FIG. 3 (Embodiment 2), the position of the circular motion axis 26 on the rotary disk 22 is shown in FIG.
In the third embodiment, the mounting position of the eccentric cam 29 on the rotary shaft 30 can be adjusted by adjusting the above method.

According to the fourth embodiment of the present invention, not only a molded product 19 having a large molding surface outer diameter without a step groove can be obtained, but also the translational rotation amplitude and the rotational speed of the molding die are adjusted. By doing so, the outer diameter and the inside thickness of the molded product 19 can be changed.

[0032]

As described above, according to the method and apparatus for molding molten glass of the present invention, a glass molded article (glass gob, glass lens) having a large molding surface outer diameter (φ11 mm or more) without a step groove is provided. ) Can be stably molded.

[Brief description of drawings]

FIG. 1 is a diagram showing a relationship between an elapsed time after contact with a molding die and a glass temperature.

FIG. 2 is a sectional view showing Embodiment 1 of the present invention.

FIG. 3 is a sectional view showing Embodiment 2 of the present invention.

FIG. 4 is a sectional view showing a third embodiment of the present invention.

FIG. 5 is an explanatory diagram for explaining a conventional technique.

[Explanation of symbols]

 1 Molten Crucible 2 Glass 3 Crucible Heater 4 Supply Nozzle 10 Nozzle Heater 11 Plunger 12 Mold 14 Glass Droplet 16 Bucket 15 Drop Path 17 Base 18 Rotating Axis 19 Molded Product 20 Rotating Plate 21 Twisting Spring 23 Arm 27 Bucket Holder 31 Sliding Dynamic rotation member

Claims (5)

[Claims] 1. A method for forming a molten glass in which molten glass is dropped onto a forming die to transfer the shape of the glass to the glass, and translational rotation is performed to rotate the position of the forming die without changing the attitude and orientation of the forming die. A molten glass droplet is dropped onto a molding die, and the outer diameter of the molding surface of the glass droplet is enlarged within 0.2 seconds after the drop. 2. A rotary disk is provided, the mold is rotatably mounted at a position separated from a rotary shaft of the rotary disk by a distance equal to or smaller than a radius of the mold, and the winding is wound at a distance of at least one end of an outer periphery of the mold. A molten glass molding apparatus, characterized in that a spring is connected and pulled so that the mold can be translated and rotated by the rotation of the rotary disk. 3. A rotating disk is provided, and one end of an arm is rotatably fixed at a position distant from a center of rotation of the rotating disk,
At the other end of the arm, there is a sliding / rotating member for fixing the mold and holding the middle part of the arm slidably and rotatable, so that the mold can be translated and rotated by the rotation of the rotary disk. An apparatus for forming molten glass, characterized in that 4. A bearing is mounted on the outer periphery of a cylindrical eccentric cam having an eccentric rotation shaft, and a bucket is provided to hold the outer periphery of the bearing and the molding die concentrically. An apparatus for forming molten glass, characterized in that a helical spring is connected and pulled so that the forming die can be translated and rotated by the rotation of the rotating shaft. 5. A method of forming a molten glass in which molten glass is dropped onto a molding die to transfer the shape of the glass to the glass, and the molten glass droplet is dropped onto a translationally rotating molding die, and the translational rotation amplitude and By adjusting the rotation speed,
A method for forming molten glass, which comprises changing the outer diameter and the inside thickness of a molded product.