JP3689259B2 - Optical element material manufacturing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical element material manufacturing apparatus.
[0002]
[Prior art]
In recent years, when manufacturing optical elements such as lenses and prisms, the glass droplets that naturally drop from the outflow nozzle connected to the melting vessel that melts the glass material are cooled and solidified. It has been practiced to use the glass drop as an optical element material. Among manufacturing apparatuses that realize such a method, there is an apparatus disclosed in Japanese Patent Application Laid-Open No. 61-146721 and configured as shown in a simplified manner in FIG. Is a platinum melting container 52 that melts the glass material 51 that has been charged, an outflow nozzle 53 that is connected to the bottom of the melting container 52, and a glass drop 54 that is dropped from the tip of the outflow nozzle 53. And a jig 55.
[0003]
That is, in this manufacturing apparatus, the separation distance (dropping distance) L between the glass droplet 54 and the receiving jig 55 is set to a length sufficient to cool and solidify the surface of the glass droplet 54 in advance. The collected glass droplet 54 is collected and used as an optical element material. If it is received with insufficient solidification, distortion due to a temperature difference between the surface of the glass drop 54 and the receiving jig 55, that is, a so-called orange peel occurs, and an optical element material with good quality cannot be obtained. In addition, when the mass of the glass droplet 54 is large, a long dropping distance L is required, and therefore the illustration is omitted, but the glass droplet 54 being dropped is forcibly blown with air. It has also been proposed to cool.
[0004]
Also, there is a manufacturing apparatus disclosed in Japanese Patent Laid-Open No. 5-43258 and simplified as shown in FIG. 7. In this manufacturing apparatus, a glass rod is used by using a heating device 61 such as a heater. The tip of 62 is locally heated, melted and spheroidized, and then received by the receiving jig 64 to receive the glass droplet 63 that drops naturally. In the case of this manufacturing apparatus, a cooling cylinder 65 having a length corresponding to the dropping distance L required for cooling and solidifying the surface of the glass droplet 63 is disposed between the glass droplet 63 and the receiving jig 64. In addition, the glass droplet 63 being dropped is forcibly cooled by the air blown from the lower part of the cooling cylinder 65.
[0005]
[Problems to be solved by the invention]
By the way, the following disadvantages have occurred in the optical element material manufacturing apparatus according to the conventional embodiment. That is, when air is blown to promote cooling and solidification of the glass drops 54, 63, air convection occurs on the surfaces of the glass drops 54, 63, and the surface tension is acting because the surface temperature becomes unstable. Is not uniform, the sphericity of the optical element material is impaired. As long as the glass droplets 54 and 63 are solidified with the surface tension being non-uniform, the internal stress state also remains non-uniform and the impact resistance is inevitably lowered. , 64 may cause the glass drops 54, 63 to break, resulting in a decrease in production efficiency. Further, when air is blown, dust or the like blown together with air may adhere to the surfaces of the glass droplets 54 and 63, and if dust or the like adheres, the quality of the optical element material is degraded. turn into.
[0006]
The present invention was devised in view of these disadvantages, and it is possible to quickly cool and solidify glass droplets without blowing air, while increasing the sphericity of the glass droplets. An object of the present invention is to provide an optical element material manufacturing apparatus configured to improve quality.
[0007]
[Means for Solving the Problems]
An apparatus for manufacturing an optical element material according to claim 1 of the present invention includes a thin film body that receives a glass drop dripping from a tip of an outflow nozzle that is connected to a melting vessel that melts a glass material. The body is characterized by excellent flexibility and heat dissipation. In this case, the thermal conductivity of the thin film body is preferably 300 W / (m · K) or more, and the heat-resistant temperature is preferably 500 ° C. or more. And if it is this structure, since the dripped glass drop is received by the flexible thin film body, and the calorie | heat amount which a glass drop has will be rapidly dissipated through a thin film body with favorable heat dissipation, a glass drop Therefore, an optical element material with improved sphericity can be produced without generating orange peel. Moreover, since it is not necessary to lengthen the dropping distance and it is not necessary to blow air, an advantage that the manufacturing apparatus can be reduced in size can be secured.
[0008]
An optical element material manufacturing apparatus according to a second aspect of the present invention is the optical element material manufacturing apparatus according to the first aspect, wherein the thin film body is configured to move along a direction intersecting a dropping direction of the glass droplets. Features. An optical element material manufacturing apparatus according to a third aspect of the present invention is the optical element material manufacturing apparatus according to the first aspect, and the thin film body is disposed in an inclined state along a direction intersecting a dropping direction of the glass droplets. It is characterized by. An optical element material manufacturing apparatus according to a fourth aspect of the present invention is the optical element material manufacturing apparatus according to the third aspect, wherein the solidified glass droplets are collected at a lower position of the thin film body disposed at an inclination. A container is arranged.
[0009]
An optical element material manufacturing apparatus according to a fifth aspect of the present invention is the optical element material manufacturing apparatus according to the first aspect, wherein the thin film body is disposed with the open end of the cylindrical body closed. An optical element material manufacturing apparatus according to a sixth aspect of the present invention is the optical element material manufacturing apparatus according to the fifth aspect, wherein the thin film body disposed with the open end of the cylindrical body closed is slackened. And An optical element material manufacturing apparatus according to a seventh aspect of the present invention is the optical element material manufacturing apparatus according to the fifth aspect, wherein the thin film body disposed with the open end of the cylinder closed is changed in tension along the surface direction. It is set as the structure which carries out.
[0010]
An optical element material manufacturing apparatus according to an eighth aspect of the present invention is the optical element material manufacturing apparatus according to the fifth aspect, in which a solidified glass is provided at a peripheral position of a thin film body arranged with the open end of the cylinder closed. A collection container for collecting drops is arranged. An optical element material manufacturing apparatus according to a ninth aspect of the present invention is the optical element material manufacturing apparatus according to any one of the first to eighth aspects, wherein the thin film body has poor wettability to glass. .
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0012]
(Embodiment 1)
FIG. 1 is a cross-sectional structure diagram illustrating an optical element material manufacturing apparatus according to Embodiment 1, and FIG. 2 is a cross-sectional structure diagram illustrating an optical element molding die.
[0013]
The manufacturing apparatus according to the present embodiment includes a platinum melting container 2 that melts a glass material 1 such as a charged barium silicate glass, an outflow nozzle 3 that is connected to the bottom of the melting container 2, A thin film body, a so-called sheet body 5, which receives the glass droplet 4 that has been melted in the container 2 and dropped downward from the tip of the outflow nozzle 3 is provided. Needless to say, the glass material 1 is not limited to barium borosilicate glass, and the melting vessel 2 is not limited to platinum. And the sheet | seat body 5 here is excellent in the softness | flexibility and heat dissipation, for example, thickness is about 0.1 mm, thermal conductivity is 300 W / (m * K) or more, and heat-resistant temperature Is a polymer film sheet having a temperature of 500 ° C. or higher. The sheet body 5 is preferably a polymer film sheet, that is, a graphitized and highly oriented material, but is not limited to the polymer film sheet and is excellent in other flexibility and heat dissipation. Of course, for example, a film obtained by depositing a noble metal on a polymer may be used.
[0014]
In addition, it is preferable that the sheet body 5 has poor wettability with respect to glass. If the wettability with respect to glass is poor, there is no problem that the received glass droplet 4 adheres to the sheet body 5. Become. Further, the separation distance (dropping distance) L between the glass droplet 4 and the sheet body 5 at this time is set to, for example, about 200 mm, and the sheet body 5 itself that receives the glass droplet 4 is radiated by the sheet body 5. 1, for example, a receiving jig 6 in which a space 6 a as shown in FIG. 1 is formed, or a receiving jig (not shown) made of a material having better heat dissipation than the sheet body 5. Positioning is supported. In addition, the code | symbol 7 in a figure has shown the electric heater arrange | positioned along the outer periphery of the melting container 2, and the glass raw material 1 in the melting container 2 is fuse | melted by the heating using this electric heater 7. It has become.
[0015]
Next, the operation of the manufacturing apparatus according to Embodiment 1 will be described. First, when the solid glass material 1 is put into the melting container 2 and the glass material 1 is heated to about 1200 ° C. by the electric heater 7, the glass material 1 in the melting container 2 is melted to become a liquid glass. The material 1 flows out little by little from the tip of the outflow nozzle 3 connected to the bottom of the melting vessel 2. As a result, a spherical glass droplet 4 is formed at the tip of the outflow nozzle 3 as the surface tension of the glass itself acts, and the glass droplet 4 whose mass has increased to a certain required level In addition to being separated from the outflow nozzle 3, it is dropped onto the sheet body 5 excellent in flexibility and heat dissipation while solidifying into a spherical shape during dropping. Then, the dropped glass droplet 4 is rapidly cooled naturally through the sheet body 5 and solidified, and as a result, an optical element material is produced. Needless to say, the size of the glass droplet 4 is adjusted in advance so as to correspond to the size required for the optical element material. The size of the glass droplet 4 is based on the inner diameter of the outflow nozzle 3 and the like. It is fixed.
[0016]
That is, in this manufacturing apparatus, the dropped glass droplet 4 is received by the flexible sheet body 5 while relaxing the impact force, and the amount of heat of the glass droplet 4 passes through the sheet body 5 with good heat dissipation. As a result, the glass droplet 4 is rapidly cooled and solidified in spite of the short drop distance L. As a result, an orange peel is not generated and the surface state is good. In addition, an optical element material with improved sphericity can be produced. Then, the inventors of the present invention lowered the temperature of the recovered glass droplet 4 to below the glass transition point, and then the cavity (space) of the optical element molding die 10 shown in FIG. Glass drops 4 whose temperature has been lowered are placed in a cavity surrounded by the lower mold 12 and the body mold 13 as an optical element material, and further molded under conditions where the molding temperature is 500 ° C. to 600 ° C. and the pressing force is 70 kgf or more. As a result, it has been confirmed that both surfaces have a desired shape, and it is possible to easily obtain a glass lens with good quality.
[0017]
By the way, in the present embodiment, the sheet body 5 that receives the glass droplet 4 is positioned and arranged at the lower position facing the outflow nozzle 3. It is also possible to adopt a configuration in which the sheet body 5 is moved along a direction intersecting the dropping direction, for example, the horizontal direction in FIG. If they are sequentially changed, the advantage that the life of the sheet member 5 can be easily extended can be secured. In the case where the sheet body 5 is moved, although not shown, a configuration in which the sheet body 5 is received and moved together with the receiving jig 6 by an air cylinder or the like is employed.
[0018]
(Embodiment 2)
FIG. 3 is a cross-sectional structural view showing the optical element material manufacturing apparatus according to the second embodiment. In FIG. 3, parts and portions that are the same as or equivalent to those in FIGS. . That is, the manufacturing apparatus according to the present embodiment includes a platinum melting container 2 for melting a glass material 1 such as borosilicate barium glass, an electric heater 7 disposed along the outer periphery of the melting container 2, An outflow nozzle 3 connected to the bottom of the melting vessel 2 and a thin film body for receiving a glass drop 4 dropped downward from the tip of the outflow nozzle 3, that is, a sheet body 5 excellent in flexibility and heat dissipation. And a polymer film sheet. In this case, the sheet body 5 is arranged in a state of being inclined along the direction intersecting with the dropping direction (the vertical direction in the drawing) of the glass droplet 4 (in the drawing, being inclined upward to the right), and the space portion. It is positioned and supported by a receiving jig 6 on which 6a is formed.
[0019]
In the present embodiment, for example, the separation distance between the glass droplet 4 and the sheet body 5, that is, the dropping distance L is set while the inclination angle of the sheet body 5 is about 30 ° with respect to the horizontal direction. Although it is set to about 150 mm, the inclination angle and the drop distance L are not limited to these numerical values, and it is a matter of course that the numerical values are set as required. Further, in the second embodiment, a collection container 8 is disposed at a lower position (lower left position in the figure) of the sheet body 5 disposed in an inclined state. Depending on the collection container 8, solidification may occur. Then, after being dropped and received by the sheet body 5, a large number of glass droplets 4 collected while rolling along the sheet body 5 are to be collected. And the glass droplet 4 collected by this collection container 8 will be collect | recovered as an optical element raw material.
[0020]
Below, the procedure at the time of producing an optical element raw material using the manufacturing apparatus which concerns on Embodiment 2 is demonstrated. First, when the solid glass material 1 is put into the melting container 2 and the glass material 1 is heated to about 1200 ° C. by using the electric heater 7, the glass material 1 in the melting container 2 is melted. At the tip of the outflow nozzle 3 that is connected to the bottom of the glass 2, a spherical glass droplet 4 is formed as the surface tension of the glass itself acts. And the glass droplet 4 whose mass has increased to a certain required level will be separated from the outflow nozzle 3, and the glass droplet 4 dropped away from the outflow nozzle 3 is excellent in flexibility and heat dissipation and in an inclined state. It is dripped toward the sheet body 5 arranged in (1).
[0021]
Further, the glass droplet 4 that has been dropped while solidifying into a spherical shape and received by the sheet body 5 rapidly cools naturally while rolling on the inclined sheet body 5 toward its lower position. As a result, the material is solidified and becomes an optical element material, and is collected by the collection container 8 disposed at the lower position of the sheet body 5. After that, the glass droplets 4 are sequentially dropped from the outflow nozzle 3 toward the sheet body 5, and the dropped glass droplets 4 are accumulated in the collection container 8. That is, in the manufacturing apparatus having such a configuration, the dropped glass droplet 4 is rapidly cooled while rolling on the sheet body 5 having excellent heat dissipation, so that the surface does not generate orange peel. An optical element material having a good state and improved sphericity can be obtained.
[0022]
By the way, the bottom surface of the receiving jig 6 may be curved as shown by the phantom line in FIG. 3. In such a configuration, the sheet body 5 is inserted through the receiving jig 6. The position where the dropped glass droplet 4 is received can be different even in the sheet body 5. And if such a structure is employ | adopted, the advantage that it becomes easy to aim at the lifetime improvement etc. of the sheet | seat body 5 will be ensured.
[0023]
(Embodiment 3)
FIG. 4 is a cross-sectional structural view showing the optical element material manufacturing apparatus according to Embodiment 3, and FIG. 5 is an explanatory view showing the operation of the sheet member. 4 and 5, parts and portions that are the same as or correspond to those in FIGS. 1 to 3 are denoted by the same reference numerals. The manufacturing apparatus according to the present embodiment includes a platinum melting container 2 for melting a glass material 1 such as borosilicate barium glass, an electric heater 7 disposed along the outer periphery of the melting container 2, and a melting container. 2 and a thin film body for receiving a glass droplet 4 dropped downward from the tip of the outflow nozzle 3, that is, a polymer that is a sheet body 5 having excellent flexibility and heat dissipation. And a film sheet.
[0024]
And the sheet | seat body 5 here is made into cylindrical shape, a rectangular tube shape, etc., obstruct | occludes the upper open end part of the cylinder 9 arrange | positioned along the vertical direction, and has been slackened to some extent. The collection container 10 for collecting the solidified glass droplet 4 is disposed at a distance from the glass droplet 4, that is, at a peripheral position of the sheet body 5 where the dropping distance L is about 150 mm. Has been placed. That is, depending on the sheet body 5 included in the manufacturing apparatus according to the present embodiment, the sheet body 5 itself swells toward the outflow nozzle 3 by the repulsive force when the dropped glass droplet 4 is received. Dropping the droplet 4 into the collection container 10 is performed. In addition, if the sheet body 5 that closes the open end of the cylindrical body 9 is slack, the advantage that further flexibility is ensured is ensured, but the sheet body 5 does not necessarily have to be slackened. Of course.
[0025]
By the way, in FIG. 4, although the collection container 10 is integrated with the base of the cylinder 9, it is not necessarily integrated, and what is the collection container 10 with the base of the cylinder 9? It goes without saying that it may be a separate body. Further, it is not necessary that the sheet body 5 is fixedly supported by the cylinder body 8. For example, the sheet body 5 is pulled by pulling the other end side of the sheet body 5 whose one end side is fixedly supported by an air cylinder or the like. It is also possible to change the tension along the surface direction of 5. And when such a structure is employ | adopted, as a result that a repulsive force can be adjusted with changing the tension | tensile_strength along the surface direction of the sheet | seat body 5, the glass droplet 4 is collected in the collection container 9 as a result. It is possible to reliably put it in.
[0026]
Next, a procedure for manufacturing an optical element material using the manufacturing apparatus according to Embodiment 3 will be described. First, when the glass material 1 is charged into the melting container 2 and heated using the electric heater 7, the glass material 1 in the melting container 2 is melted and connected to the bottom of the melting container 2. A spherical glass droplet 4 is formed at the tip of the outflow nozzle 3. Thereafter, the glass droplet 4 whose mass has increased to a certain required level will be separated from the outflow nozzle 3, and the glass droplet 4 dripped away from the outflow nozzle 3 is a sheet body 5 excellent in flexibility and heat dissipation. I can accept it.
[0027]
However, since the sheet body 5 at this time has been slackened to some extent in advance, as shown in FIG. 5 (a), the sheet body 5 is further deflected by receiving the glass droplet 4, and in FIG. 5 (b). As shown, since the sheet body 5 swells toward the outflow nozzle 3 by the action of the repulsive force generated as it bends, the glass droplet 4 rapidly cools naturally while rolling on the swelled sheet body 5. Then, it is collected by the collection container 10. In the present embodiment, the glass droplet 4 is introduced into the collection container 10 by the repulsive force of the sheet body 5 itself that has received the glass droplet 4. For example, the cylindrical body closed by the sheet body 5 is used. The sheet body 5 is sucked by evacuating the inside of the sheet 9, and when the sheet body 5 receives the glass droplet 4, the vacuum is released and the sheet body 5 is inflated to catch the glass droplet 4. It is also possible to put it into the collection container 10.
[0028]
【The invention's effect】
As described above, according to the optical element material manufacturing apparatus of the present invention, a thin film body that receives a glass drop dripping from the tip of an outflow nozzle connected to a melting container that melts the glass material is provided. And, since this thin film body is supposed to be excellent in flexibility and heat dissipation, it is possible to quickly cool and solidify glass droplets without blowing air, The effect that the quality can be improved while increasing the sphericity of the glass droplet as the optical element material can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional structure diagram showing an optical element material manufacturing apparatus according to a first embodiment.
FIG. 2 is a sectional structural view showing an optical element molding die.
FIG. 3 is a cross-sectional structure diagram illustrating an optical element material manufacturing apparatus according to a second embodiment.
4 is a cross-sectional structure diagram showing an optical element material manufacturing apparatus according to Embodiment 3. FIG.
FIG. 5 is an explanatory diagram showing the operation of the sheet member.
FIG. 6 is a cross-sectional structure diagram showing an optical element material manufacturing apparatus according to a conventional embodiment.
FIG. 7 is a cross-sectional structure diagram showing an optical element material manufacturing apparatus according to a conventional embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Glass material 2 Melting container 3 Outflow nozzle 4 Glass drop 5 Sheet body (thin film body)

Claims (9)

It has a thin film body that catches a glass drop dripping from the tip of an outflow nozzle that is connected to a melting container that melts the glass material, and this thin film body is excellent in flexibility and heat dissipation. Optical element material manufacturing equipment. An optical element material manufacturing apparatus according to claim 1,
An apparatus for manufacturing an optical element material, wherein the thin film body is configured to move along a direction intersecting a dropping direction of the glass droplet. An optical element material manufacturing apparatus according to claim 1,
The thin film body is disposed in an inclined state along a direction intersecting with the dropping direction of the glass droplets. An optical element material manufacturing apparatus according to claim 3,
An apparatus for producing an optical element material, characterized in that a collection container for collecting solidified glass droplets is disposed at a lower position of the thin film body disposed at an inclination. An optical element material manufacturing apparatus according to claim 1,
An apparatus for manufacturing an optical element material, wherein the thin film body is disposed so as to close an open end of the cylindrical body. An optical element material manufacturing apparatus according to claim 5,
An apparatus for producing an optical element material, characterized in that the thin film body arranged with the open end of the cylinder closed is slackened. An optical element material manufacturing apparatus according to claim 5,
An apparatus for manufacturing an optical element material, characterized in that a thin film body arranged by closing an open end portion of a cylindrical body is configured to change a tension along a surface direction thereof. An optical element material manufacturing apparatus according to claim 5,
An apparatus for manufacturing an optical element material, wherein a collection container for collecting solidified glass droplets is arranged at a peripheral position of a thin film body arranged by closing an open end portion of a cylindrical body. An apparatus for manufacturing an optical element material according to any one of claims 1 to 8,
An apparatus for manufacturing an optical element material, wherein the thin film body has poor wettability with respect to glass.

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