JP3524567B2 - Method and apparatus for molding glass optical element - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for forming a glass optical element by heating and melting a glass element, supplying it to a molding die, press-molding it, and cooling it.

[0002]

2. Description of the Related Art Conventionally, as this kind of technique, for example, a glass molding crucible disclosed in Japanese Utility Model Laid-Open No. 63-199137 is known. This apparatus is provided with a tube having an inlet near the bottom in the crucible, and the tube is formed at least outside the crucible and above the maximum level of the molten glass contained in the crucible to form the outlet. The molten glass near the bottom of the crucible is made to flow out by inclining the crucible toward its outlet or by injecting gas into the crucible.

Further, in Japanese Laid-Open Patent Publication No. 4-280822, a glass block having a volume larger than that of a desired molded product and having a free shape is used as a glass material, and while supporting the outer peripheral portion of the glass material, By blowing a high-temperature gas at a temperature above the softening point onto the glass material to heat and soften the glass material, the glass material is allowed to fall by its own weight, the surface of the glass material is forcibly cooled during the falling process, and then downward in the falling direction. After dropping the glass material on the placed lower mold and placing the lower mold and the upper mold coaxially opposite each other,
A molding method is disclosed in which press molding is performed using the upper and lower molds.

[0004]

However, the above-mentioned conventional device has the following problems. That is, in the glass molding crucible described in Japanese Utility Model Application Laid-Open No. 63-199137, the molten glass is a viscous fluid and wets the inner wall of the crucible, which makes it difficult to accurately separate a predetermined weight of molten glass from the crucible. There was a problem.

Further, in the forming method described in Japanese Patent Laid-Open No. 4-280822, even if the high temperature gas is blown onto the surface of the glass material only by supporting the outer peripheral portion of the glass material, a completely smooth surface having no defects can be obtained. There is a problem in that a processing step for improving the surface roughness of the glass material is required in advance because it falls.

The present invention has been made in view of the above problems, and it is possible to use a glass material having a rough surface, which is low in cost, and the glass material heated and melted can be supplied to a molding die in a predetermined weight. It is an object of the present invention to provide a glass optical element molding method and a molding apparatus.

[0007]

In order to achieve the above object, in the glass optical element molding method of the present invention according to claim 1, the lower end of the holding cylinder serves as a glass material holding means for heating and softening the glass material. In the holding cylinder, the glass material is held while being sucked, or the upper end of the holding cylinder is held by the glass material while being discharged from the holding cylinder. It is characterized in that after the surface is heated to be mirror-finished, the glass material is supplied to a molding die, pressed, and cooled to a glass transition temperature or lower.

In the glass optical element molding apparatus of the present invention according to claim 2, the glass material is heated to be softened,
A molding apparatus for molding a glass optical element by pressing with a molding die, wherein a pair of molding dies that are coaxially opposed to each other, at least one of which is axially movable, a heating means for heating a glass material, and at least one of A holding cylinder for sucking and holding a glass material by negative pressure, wherein the glass material is sucked and held by the holding cylinder while being heated and softened by the heating means, and then press-molded by the pair of molding dies. There is.

Further, in the glass optical element molding apparatus of the present invention according to claim 3, the glass material is heated to soften it and is pressed by a molding die to mold the glass optical element. A pair of molding dies, at least one of which is movable in the axial direction facing each other, heating means for heating the glass material, and at least one holding cylinder for holding the glass material at the upper end by positive pressure. While being held by the holding cylinder, it is heated and softened by the heating means, and then press-molded by the pair of molding dies.

[0010]

In the glass optical element molding method and molding apparatus of the present invention having the above-described structure, even if the glass material is heated and the glass material is softened and easily deformed by heating the surface of the glass material, With the configuration in which the glass element is held while sucking, the downward movement of the glass element due to its own weight is offset by being accommodated in the holding cylinder by suction, and the drop is prevented. Further, since the glass material is held at the upper end of the holding cylinder while being discarded from the inside of the holding cylinder, the downward movement of the glass material due to its own weight is exhausted from the inside of the holding cylinder and a positive pressure is applied to offset the deformation.

As described above, even if the surface of the glass material is heated, it does not drop as in the prior art, and the glass material can be sufficiently held until it becomes a mirror surface. Therefore, it is possible to use a low-cost rough glass material. Further, by heating the surface of the glass material with these holding means, a glass material having a mirror-finished whole surface can be obtained. Further, since the holding of the glass material during heating and softening is a partial contact by the holding tube, the adhesion of the glass to the holding tube is very small, and the glass material can be easily separated from the holding tube. And, by using the weighed glass material, it is possible to suppress the weight fluctuation of the glass material due to the separation from the holding cylinder, and it is possible to supply the heat-softened glass material with stable weight accuracy to the molding die. become.

[0012]

Embodiment 1 An embodiment of a glass optical element molding method and molding apparatus according to the present invention will be described below with reference to the accompanying drawings. First, the first embodiment will be described with reference to FIGS. 1
Is a glass material obtained by cutting from a glass block material or pressing from molten glass, and is weighed in a weight corresponding to a desired optical element. The surface of the glass material 1 is a rough surface, and finish processing of roughness is not necessary. However, cutting powder adhering to the surface and dirt such as a release agent in the pressing process have been washed and removed in advance.

Reference numeral 2 is a first adsorption cylinder made of a material that does not deteriorate even at high temperatures such as Pt and Au, and has a pipe shape. The upper end of the first suction cylinder (holding cylinder) 2 is connected to the first suction cylinder 3 in a sealed state.
The upper end of the suction cylinder 3 is connected to a negative pressure generation source (not shown). Further, the first suction cylinder 3 is fixed to the first transport arm 4, and the first transport arm 4 can be moved and stopped at an arbitrary position by a robot mechanism (not shown). .

Reference numeral 5 is a first heating furnace (heating means) having an opening 5a at its upper end, and the internal temperature can be arbitrarily set by a temperature controller (not shown). Further, 6 is a second suction cylinder (holding cylinder) , and 7 is a second suction cylinder, which are configured similarly to the first suction cylinder 2 and the first suction cylinder 3. 8 is a second carrier arm,
It supports the suction cylinder 7 and is rotatably attached to the robot arm 9. The robot arm 9 is the first transfer arm 4
Similarly to the above, the robot mechanism (not shown) can move and stop at any position. Further, 10 is a second heating furnace (heating means) having an opening 10a at the upper end, and the internal temperature can be arbitrarily set by a temperature controller (not shown).

Numeral 11 is a lower die (molding die) made of a material having heat resistance such as AlN, BN, Cr ₂ O _{3 and the} like, which is hard to be wet with molten glass, and the molding surface 11 a of the upper end surface is desired. Precisely mirror-finished in a shape corresponding to the optical element. A molding machine base 12 has a lower mold 11 fixedly supported. A heater 13 for heating the lower mold 11 to a predetermined temperature is closely attached to the periphery of the lower mold 11. A ring-shaped body mold 14 is removably fitted around the upper end of the lower mold 11. The barrel mold 14 is made of a heat-resistant material having a linear expansion coefficient smaller than that of glass to be molded.

An upper mold (molding mold) 15 coaxially with the lower mold 11
Is supported by the movable base 16 to be retracted, and is lowered to sandwich the heat-softened glass 100 located on the molding surface 11a of the lower mold 11 and apply a predetermined pressing pressure to perform molding. . In addition, 17 is a heater for heating the upper mold 15, and 18 is a discharge arm that is vertically and horizontally movable.

Next, SF11 (transition temperature 467 ° C., which is a heavy flint type optical glass, is used by the above-mentioned apparatus.
A method for forming a biconvex lens having a weight of 1.5 g by using a softening point temperature of 568 ° C. and a linear expansion coefficient of 8 × 10 ⁻⁶ / ° C. will be described.

First, the glass block of SF11 is cut to prepare a substantially cubic glass material having a weight of 1.5 g.
The surface roughness of this glass material may be a rough surface of about Rmax 10 μm. This is the tip 2 of the adsorption cylinder 2 made of Pt.
Suction and adsorb to a. In this state, the glass material 1 is moved into the heating furnace 5 and stopped. The internal temperature of the heating furnace 5 is set to 600 ° C. in advance. With time, the temperature of the glass material 1 approaches the temperature in the heating furnace 5, and its viscosity decreases. After 10 minutes, the glass material 1 is pulled up from the heating furnace 5. At this time, the glass material 1 is softened by the drawing of the glass suction surface into the suction cylinder 2 as shown in 1'of FIG. 2 to offset the action of moving downward due to its own weight. To be done. Due to the heating and softening effect during this period, the surface roughness of the lower surface of the glass material is gradually improved by the surface tension, and a mirror surface with Rmax of 5 μm or less can be obtained. FIG. 7 shows the relationship between the ultimate viscosity of the heated glass material and the surface roughness of the glass surface after heating, and the set temperature and heating time of the heating furnace 5 are set based on this figure.

At this stage, since the adsorption surface of the glass material 1'is not sufficiently mirror-finished, the following steps are carried out. First, as shown in FIG. 2, the second suction cylinder 6 is attached to the glass material 1 '.
The lower surface of the first suction cylinder 2
Release the suction on the side and save. At this time, the glass material is easily separated from the adsorption cylinder 2, but it is desirable that the glass arrival viscosity due to the heating is as high as about 10 ⁵ poise so that the tip of the adsorption cylinder is less likely to be wetted and separated. next,
The second transport arm 8 is inverted and fixed, and as shown in FIG.
The glass material 1'is moved into the second heating furnace 10 and stopped, and similarly held for 10 minutes. The second heating furnace 10
Similarly, the set temperature was set to 600 ° C. The entire surface of the heat-softened glass 100 thus obtained was mirror-finished.

Then, as shown in FIG. 4, the heat-softened glass 10 is formed on the molding surface 11a of the lower mold 11 heated to 450.degree.
After transporting 0, the suction cylinder is evacuated and supplied to the lower mold. The barrel die 14 is made of a cemented carbide having a linear expansion coefficient of 6 × 10 ⁻⁶ / ° C.

Then, the upper mold 1 immediately heated to 450 ° C.
5 is lowered, and a pressing pressure of 80 kg / cm ² is applied to cool the glass element to the glass transition temperature or lower while molding it into an optical element shape. The glass optical element after molding is integrated with the barrel mold 14, and the upper mold 15 is raised and retracted, and then the discharge arm 18 is moved to the barrel mold 14.
It is located on the outer circumference, and then lifts to release from the lower mold, and is retracted and taken out. When the glass mold and the molded glass optical element are cooled to room temperature, due to the difference in linear expansion coefficient,
The glass optical element can be easily taken out from the barrel mold.

As described above, according to this embodiment, it is possible to manufacture a glass optical element having a mirror-finished desired shape by using a glass material having a rough surface.

As a modified example, the first heating furnace and the second heating furnace
It is also possible to construct a line in which the heating furnace, the lower mold and the upper mold are connected to each other, and the glass material is continuously heated and molded to be manufactured. Further, the weight of the glass material or the glass material is not limited to that in this embodiment.

[0024]

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIGS. Reference numeral 19 is a holding cylinder made of a material that does not deteriorate even at high temperatures, such as Pt and Au, and has a pipe shape, and its tip is supported upward. Further, the tip portion has a step portion 19a. The lower end of the holding tube 19 is connected to the exhaust tube 20 in a hermetically sealed state.
The lower end of is connected to a positive pressure generation source (not shown). Further, the exhaust stack 20 is fixed to the first transport arm 21,
The first transfer arm 21 can be moved and stopped at an arbitrary position by a robot mechanism (not shown). 22 is a first heating furnace having an opening 22a at the lower end.
(Heating means) , a temperature controller (not shown)
Allows the internal temperature to be set arbitrarily.

Reference numeral 23 is an adsorption cylinder (holding cylinder) made of a material that does not deteriorate even at high temperatures such as Pt and Au, and has a pipe shape, and its tip is supported downward. The upper end of the suction cylinder 23 is connected to the suction cylinder 24 in a sealed state, and the upper end of the suction cylinder 24 is connected to a negative pressure generation source (not shown). Further, the suction cylinder 24 is used for the second transport arm 2.
The second transport arm 25 can be moved to an arbitrary position and stopped by a robot mechanism (not shown).

Next, a method of molding a glass optical element similar to that of Example 1 by using the apparatus having the above-mentioned structure will be described. After placing the glass material 1 on the stepped portion 19a of the holding cylinder 19, the glass material 1 is moved into the first heating furnace 22 and stopped, and the inside of the holding cylinder is set to a positive pressure. The first heating furnace 22 is set to 650 ° C. in advance. With time, the temperature of the glass material 1 approaches the temperature in the heating furnace 22, and its viscosity decreases. After 7 minutes, the glass material 1 is pulled up from the heating furnace 22. The glass material is held without falling because the lower surface of the glass cancels the action of softening by the positive pressure of the holding cylinder 19 and moving downward due to its own weight. Due to the heating and softening action during this time, the surface roughness of the upper surface of the glass material is gradually improved due to the surface tension, and a mirror surface with Rmax of 0.05 μm or less can be obtained. Also in this embodiment, as in the first embodiment, the set temperature and the heating time of the first heating furnace 22 are set with reference to FIG. 7.

At this stage, since the lower surface of the glass material 1'is not sufficiently mirror-finished, the following steps are carried out. First,
As shown in FIG. 9, the adsorption cylinder 23 is brought into contact with the upper surface of the glass material 1 ′ to adsorb it, and the holding cylinder 19 is retracted. At this time, the glass material is easily separated from the holding cylinder 19, but it is desirable that the glass reaching viscosity due to the heating is as high as about 10 ⁵ poise so that the tip of the adsorption cylinder is less likely to be wetted and separated. Next, similarly to FIG. 3, the glass material 1 ′ is moved into the second heating furnace 10 and stopped, and similarly held for 7 minutes. The set temperature of the second heating furnace 10 was 650 ° C. The entire surface of the heat-softened glass 100 thus obtained was mirror-finished. After this, lower mold 1
The steps in which the heat-softened glass 100 is conveyed to 1, the upper mold 15 presses and cools, and the carry-out arms 18 take out through the body mold 14 are the same as in the first embodiment.

Also in this embodiment, as in the first embodiment,
It is possible to manufacture a glass optical element having a desired shape with a mirror surface by using a glass material having a rough surface.

[0029]

Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIGS. 1 is a glass material similar to that of Example 1, and is formed in a short columnar shape. Reference numeral 32 denotes a first suction cylinder (holding cylinder) made of the same material as that of the first embodiment, which has a pipe shape, and the tip portion 32a has a flat shape thinner than the thickness of the glass material 1 and the glass material 1 Is formed in an arc shape along the outer peripheral surface of the. Reference numeral 33 denotes a first suction cylinder similar to that of the first embodiment, the lower end of which is hermetically connected to the upper end of the first adsorption cylinder 32, and the upper end of which is connected to a negative pressure generation source with a control device (not shown). Reference numeral 34 denotes a first transport arm, which is shown in FIG.
10, the first suction cylinder 33 is held vertically above the center of the glass material 1, and the first suction cylinder 33 is moved back and forth in the direction of arrow B1 in FIG. 10 by a guide / drive mechanism (not shown). It is a thing.

Further, 36 is a second holding cylinder , and 37 is a second holding cylinder .
An exhaust pipe , 38 is a second transport arm, and is the first suction cylinder 3
2, the first suction cylinder 33, and the first transport arm 34 have substantially the same configuration, and move back and forth in the direction of arrow B2 in FIG. And
One end of the second exhaust cylinder 37 is connected to a positive pressure generating source with a control device (not shown), and the second holding cylinder 36 is arranged so as to form an angle of about 45 ° from a direction right below the center of the glass material 1. Set up.

Reference numeral 39 is a third holding cylinder , and 40 is a third exhaust.
A cylinder 41 is a third transport arm, which is configured similarly to the second holding cylinder 36, the second exhaust cylinder 37, and the second transport arm 38.
One end of the third exhaust cylinder 40 is connected to a positive pressure generating source with a control device (not shown), and as shown in FIG. 10, a second holding cylinder 36, a second exhaust cylinder 37, a second transport arm 38, and It moves back and forth in the direction of arrow B3 at substantially symmetrical positions.

Reference numeral 35 is a first burner, which is connected and held at the tip of a first supply cylinder 45 which also serves as a carrying arm. At the tip of the first burner 35, a mixed gas of acetylene and air supplied through the first supply cylinder 45 by a control device (not shown) is combusted, and a combustion gas of a constant high temperature is blown to blow the glass. It is configured to heat the first surface of the material 1 and to move back and forth in the direction of arrow C1 in FIG. 11 by a guide / drive mechanism (not shown) via the first supply cylinder 45.

Reference numeral 55 is a second burner, and 65 is a second supply cylinder, which is constructed in the same manner as the first burner 35 and the first supply cylinder 45 and is opposed thereto, and is made of the glass material 1. Combustion gas is blown onto the second surface to heat it, and the second surface advances and retreats in the direction of arrow C2.

Reference numeral 51 denotes a first material made of the same material as in the first embodiment.
The molding surface of the tip of the molding die 51a is precisely machined into the first desired shape as in the first embodiment, and the first heater 53 similar to that in the first embodiment is closely attached to the periphery thereof. Installed. Reference numeral 52 is a first mount, which fixes and supports the first molding die 51 at its base,
The pressurizing mechanism is configured to move back and forth in the direction of arrow D1 in FIG.

Reference numeral 61 is a second molding die, and the molding surface 61a at the tip thereof is precision machined into a second desired shape. 62
Is a second mount, and 63 is a second heater, which are configured similarly to the first mount and the first heater 53. The second molding die 61, the second mount 62, and the second heater 63 are arranged in the first molding die 5
1, the first mount 52, and the first heater are arranged coaxially and opposite to each other, and are configured to move back and forth in the direction of arrow D2 in FIG. 11 by a guide / pressurizing mechanism (not shown).

Reference numeral 74 designates a generally ring-shaped first barrel mold made of the same material as that of the first embodiment, the inner diameter of which is slightly larger than the diameter of the tip of the first molding mold 51, and the first holding member. It is configured to be held coaxially with the first molding die 51 by 75, and to be moved back and forth in the direction of arrow E1 in FIG. 11 by a guide / drive mechanism (not shown).

Reference numeral 84 denotes a second barrel die, the inner diameter of which is slightly larger than the diameter of the tip of the second die 61, and is held coaxially with the second die 61 by the second holding member 85.
A guide / drive mechanism (not shown) is configured to move back and forth in the direction of arrow E2 in FIG.

Next, a method for molding a glass optical element with the apparatus having the above-mentioned structure will be described. First, a glass element 1 having a short cylindrical shape, which is almost the same as that in the first embodiment, is manufactured. As shown in FIGS. 10 and 11, the glass element 1 is attached to the first suction cylinder 3
2, the second holding cylinder 36 and the third holding cylinder 39 are radially surrounded by the respective tips, and the first suction cylinder 32 has a negative pressure controlled to be half or less of the atmospheric pressure (see FIG. 10). The arrow F) is added to adsorb the second holding cylinder 36 and the third holding cylinder 36.
The holding cylinder 39 holds the positive pressure (arrows G1 and G2 in FIG. 10) controlled to be half or less of the atmospheric pressure.

In this state, as shown in FIG. 11, the combustion gas is blown by the first burner 35 and the second burner 55 to heat the glass material 1 from both front and back surfaces. Further, the first heating heater 53 is used for the first molding die 51 and the first barrel mold 74, and the second heating heater 63 is used for the second molding die 6.
The first and second barrel dies 84 are heated and maintained at a predetermined temperature as in the case of the first embodiment.

Due to the preset combustion gas temperature and heating time, both the front and back surfaces of the glass material 1 are softened to mirror surfaces as in Example 1, while the negative pressure F and the positive pressures G1 and G2 cause Although the glass material 1 is softened, it is not locally deformed extremely by its own weight and does not hang down, but is maintained at the position shown in FIGS.

Next, the first burner 35 and the second burner 55 are retracted downward, and immediately the first barrel mold 74 and the second barrel mold 84 are moved to their tip ends as shown in FIG. First
1 suction cylinder 32, second holding cylinder 36, third holding cylinder 39
Of the first suction cylinder , as shown in FIG.
32, the second holding cylinder 36, and the third holding cylinder 39 are evacuated radially while exhausting, and again the first barrel mold 74 and the second barrel mold 84 are advanced to a position where their tips are in contact with each other.

Immediately after this, as shown in FIG. 14, the first molding die 51 and the second molding die 61 are advanced, and a predetermined pressure is applied in the same manner as in Example 1 to bring the glass material 1 into an optical element. It is cooled to the glass transition temperature or lower while being shaped.
The glass element after molding has the same structure as the first embodiment.
After retracting the forming dies 51 and 61 and further cooling, the first and second body dies 74 and 84 are retracted to the positions shown in FIG. 12 to grip the outer periphery thereof, and the first and second body dies 74 and 84 are 84 is further retracted and taken out.

According to this embodiment, the first suction cylinder 32,
Since the contact between the second holding cylinder 36 and the third holding cylinder 39 and the glass material 1 is limited to the outer circumference of the glass material 1, there is a unique effect that a defect due to a trace of contact does not occur on the optical surface. .

[0044]

Fourth Embodiment Next, a fourth embodiment of the present invention will be described with reference to FIGS. The same elements as those in the third embodiment are designated by the same reference numerals and the description thereof will be omitted. 82 is an adsorption cylinder made of rod-shaped carbon
In the (holding cylinder) , the tip portion 82a has a flat shape thinner than the thickness of the glass material 1 and the glass material 1 as in the third embodiment.
Is formed in an arc shape along the outer peripheral surface of the first suction cylinder 33.
It is fixed to the first transport arm 34 via. Reference numeral 86 is a first holding rod made of rod-shaped carbon, and its tip portion 86a is formed in a flat shape thinner than the thickness of the glass material 1 and in an arc shape along the outer peripheral surface of the glass material 1, and the second conveyance rod It is fixed to the arm 38. A second holding rod 89 has the same structure as the first holding rod and is fixed to the third transport arm 41.

Reference numerals 95 and 105 denote first and second radiation type burners.
The (heating means) has a configuration similar to that of the third embodiment and is common in that gas combustion is used as a heat source, but is different in that the symmetrical object is mainly heated by radiant heat. Furthermore, in the present embodiment, the first embodiment
Unlike 3 to 3, the inside of a box-shaped cover (not shown) having an air supply port connected to a nitrogen gas supply source and an exhaust port with an opening / closing lid is provided for the entire main part included in the range of FIGS. I decided to house it.

When the glass optical element is molded by the apparatus having the above-mentioned structure, it is almost the same as in Example 3, but the molding is carried out after introducing the nitrogen gas into the box-shaped cover in advance. Further, the outer peripheral surface of the glass material 1 is the first and second holding rods 8.
The difference is that the tips of Nos. 6 and 89 are held only by contact, and that both front and back surfaces of the glass material 1 are heated by radiant heat.

According to this embodiment, the following unique effects can be obtained. Since the material of the adsorption cylinder 82 and the first and second holding rods 86, 89 that come into contact with the outer periphery of the glass material 1 is carbon,
It is hard to get wet, and is completely separated without causing stringing, and scars of contact hardly occur. Further, since the radiant burner is used, the deterioration of the glass material due to the components of the combustion gas does not occur.

[0048]

As described above, according to the method and apparatus for molding a glass optical element of the present invention, it is possible to use a glass material having a rough surface, which is low in cost, and a glass material which is heated and melted is used. It is possible to provide a molding method and a molding apparatus for a glass optical element that can supply a predetermined weight to a molding die.

[Brief description of drawings]

FIG. 1 is an elevational view showing a part of a glass optical element molding apparatus used in Example 1 of the present invention.

FIG. 2 is an elevational view showing a part of a glass optical element molding apparatus used in Example 1 of the present invention.

FIG. 3 is an elevational view showing a part of a glass optical element molding apparatus used in Example 1 of the present invention.

FIG. 4 is an elevational view showing a part of a glass optical element molding apparatus used in Example 1 of the present invention.

FIG. 5 is an elevational view showing a part of a glass optical element molding apparatus used in Example 1 of the present invention.

FIG. 6 is a perspective view showing a discharge arm of a glass optical element molding apparatus used in Example 1 of the present invention.

FIG. 7 is a graph showing the relationship between the ultimate viscosity of a heated glass material and the surface roughness of the glass surface after heating.

FIG. 8 is an elevational view showing a part of a glass optical element molding apparatus used in Example 2 of the present invention.

FIG. 9 is an elevational view showing a part of a glass optical element molding apparatus used in Example 2 of the present invention.

FIG. 10 is an elevational view showing a part of a glass optical element molding apparatus used in Example 3 of the present invention.

11 is a vertical cross-sectional view seen from the direction of arrow A in FIG.

FIG. 12 is a vertical sectional view for explaining the operation of the third embodiment of the present invention.

FIG. 13 is a vertical sectional view for explaining the operation of the third embodiment of the present invention.

FIG. 14 is a vertical sectional view for explaining the operation of the third embodiment of the present invention.

FIG. 15 is an elevational view showing a part of a glass optical element molding apparatus used in Example 4 of the present invention.

16 is a vertical cross-sectional view seen from the direction of arrow H in FIG.

[Explanation of symbols]

1 glass material 2 First adsorption cylinder 3 First suction cylinder 4 First transport arm 5 First heating furnace 6 Second adsorption cylinder 7 Second suction cylinder 8 Second transport arm 9 robot arms 10 Second heating furnace 11 Lower mold 12 Molding machine base 13 Heater 14 body type 15 Upper mold 16 movable base 17 Heater 18 discharge arm

Continuation of front page (56) Reference JP-A-3-279233 (JP, A) JP-A-6-100321 (JP, A) JP-A-7-2530 (JP, A) JP-A-55-62815 (JP , A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C03B 11/00-11/16

Claims (3)

(57) [Claims] 1. A glass material holding means for heating and softening a glass material, wherein the glass material is held while being sucked from the inside of the holding cylinder at the lower end of the holding cylinder, or exhausted from the inside of the holding cylinder at the upper end of the holding cylinder. While holding the glass material while holding the glass material, the surface of the measured glass material is heated to be mirror-finished, and then the glass material is supplied to a molding die and pressed to obtain a glass transition temperature. A method for molding a glass optical element, which comprises cooling below. 2. A molding apparatus for heating a glass material to soften it and pressing it with a molding die to mold a glass optical element, wherein a pair of molding dies coaxially opposed to each other and at least one of which is axially movable. And a heating means for heating the glass material, and at least one holding cylinder for adsorbing and holding the glass material by a negative pressure. The glass material is adsorbed and held by the holding cylinder while being heated and softened by the heating means. After that, the glass optical element molding apparatus is characterized in that press molding is performed with the pair of molding dies. 3. A molding apparatus for heating a glass material to soften it and pressing it with a molding die to mold a glass optical element, wherein a pair of molding dies coaxially opposed to each other and at least one of which is axially movable. And a heating means for heating the glass material, and at least one holding cylinder for holding the glass material at the upper end by a positive pressure, and the glass material was heated and softened by the heating means while being held by the holding cylinder. After that, the glass optical element molding apparatus is characterized in that press molding is performed with the pair of molding dies.