JP2001304418A - Mechanism and method for protecting elastic seal member in press molding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanism and a method of protecting an elastic seal member for improving durability of the elastic seal member used under an environment of high temperature. SOLUTION: This protecting mechanism and method are characterized, in that a glass element material placed in a heat softened condition is press molded by a molding form, for holding a vacuum or a required non-oxidation atmosphere in a chamber receiving the above molding form to interrupt between this atmosphere and that outside the chamber, by equipping a cooling means blowing a cooling fluid relating to an elastic seal member provided in a sealed part of the above chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a high-precision optical element such as a lens used for a camera or a video camera, which is obtained by heating and softening a glass material in a non-oxidizing atmosphere and press-molding the same. The present invention relates to a protection mechanism and a protection method for an elastic seal member in the press forming apparatus of (1).

[0002]

2. Description of the Related Art Heretofore, such a hot glass lens molding has conventionally been performed by using a molding machine such as described in Japanese Patent Application Laid-Open No. 05-186231, which was previously filed by the present applicant. For example, a molding machine having a configuration as disclosed in JP-A-05-186230 is used.

[0003] As can be seen from these publications, this type of glass lens is formed by heating the mold and the glass material in a non-oxidizing atmosphere to prevent the mold from being oxidized. This is realized by a method of performing pressure molding into a desired shape, further cooling the mold and the molded product, releasing the mold, and taking out the molded product from the mold.

However, Japanese Patent Application Laid-Open No. 05-186231
In the apparatus described in the above publication, the molding cycle can be greatly shortened, but the supply and removal of the glass material and the molded product are directly performed with respect to the high-temperature mold in a furnace in a nitrogen atmosphere. Therefore, with respect to the opening of the barrel mold, the outer periphery of the glass material or the molded product is affected by the atmosphere in the furnace, and a slight temperature difference is likely to occur between the inner central portion of the mold and the outer peripheral portion of the glass material. This is inconvenient in obtaining a very high-accuracy surface shape of the molded product. Therefore, usually, a device for installing a heat retaining heater or the like is required in the opening.

[0005] Further, in the case where the shape of the molded article is irregular and an atmospheric gas is interposed between the molding die and the glass material, and traces of the gas remain on the surface of the molded article, Ideally, a glass material that is formed into a shape of a molded product that easily leaves such traces is pressed in a vacuum atmosphere. However, in this case, since the volume in the molding furnace is large and it takes time to evacuate, molding in such a vacuum is not optimal.

In the apparatus disclosed in Japanese Patent Application Laid-Open No. 05-186230, the supply of the glass material and the removal of the molded product are carried out while being released to the atmosphere, so that the cycle becomes extremely long, and There is a problem that a large amount of cooling nitrogen is required for cooling a mold or the like.

[0007]

In the above conventional example, it is difficult to maintain the temperature of the molding atmosphere around the mold at a constant high temperature, and it is difficult to perform molding in a vacuum. The conventional example has a problem that the cycle is long and a large amount of nitrogen for cooling is required, which is not preferable in mass production.

Further, in order to improve the above-mentioned molding machine so as to be suitable for mass production, only the former molding machine is covered with a chamber as in the conventional example, and the molding die and glass are covered. It is conceivable to open the chamber and remove the molded product while the temperature is high. By doing so, the ambient temperature around the mold is stabilized, the cycle can be extremely short, and pressure molding in a vacuum can be easily performed. When the chamber is opened, the sealing member is exposed to the high-temperature atmosphere gas in the chamber, and thus deteriorates immediately, and there is a problem that a practically effective degree of durability cannot be obtained.
Also, the elastic sealing members installed in the chamber at sealing locations other than the above-mentioned opening / closing locations also have a problem in durability since the interior of the chamber is always kept at a high temperature.

The present invention has been made based on the above circumstances, and a first object of the present invention is to improve the durability of an elastic seal member used in such a high-temperature environment.
An object of the present invention is to provide a protection mechanism and a protection method for an elastic seal member.

A second object of the present invention is to provide a mechanism and method for protecting a resilient seal member, particularly where significant surfaces of the resilient seal member may be in direct contact with hot gases. To provide.

[0011]

In order to achieve the above object, the present invention provides a method for press-forming a glass material in a heat-softened state using a mold having at least one set of an upper mold and a lower mold. In a chamber for housing a mold, a vacuum or a required non-oxidizing atmosphere is maintained, and in a press forming apparatus for shutting off an atmosphere outside the chamber, the pressurizing apparatus is provided at a sealing portion of the chamber for shutting off the atmosphere. A cooling means for blowing a cooling fluid to the elastic seal member.

In this case, as an embodiment of the present invention, the cooling means may include a cooling fluid ejection port inside the chamber and near the elastic seal member. For the elastic seal member provided at the time of opening of the opening / closing portion, the ejection port is arranged so that the cooling fluid is also blown to a portion exposed to the atmosphere in the chamber.
Further, it is effective that the cooling fluid is an inert gas, preferably a cooling medium of the same type as the non-oxidizing atmosphere.

Further, according to the present invention, when a glass material in a heat-softened state is press-formed by a mold having at least one set of an upper mold and a lower mold, a vacuum or a required pressure is set in a chamber accommodating the mold. In a press molding apparatus that keeps a non-oxidizing atmosphere and shuts off the atmosphere outside the chamber, a cooling fluid is supplied to an elastic seal member provided at a sealing portion of the chamber for shutting off the atmosphere. By spraying, a protective layer against high temperatures is formed on the surface of the elastic sealing member.

[0014] In this case, as an embodiment of the present invention, in the opening / closing portion of the chamber, the supply of the glass material to the molding die is performed with respect to the elastic seal member provided for sealing the portion. At the time when the elastic seal member is exposed to a high temperature, such as when removing a molded product after press molding, a cooling fluid is sprayed on the elastic seal member, and the surface of the elastic seal member is exposed to a high temperature. It is effective to form a protective layer.

[0015]

Embodiments of the present invention will be specifically described below with reference to the drawings. Here, FIG.
1 is an overall configuration diagram of a press device. In FIG. 1, reference numeral 2 surrounds a forming die composed of a body die 3, a lower die 6, an upper die 7, and a bottom plate 4, and the atmosphere inside and around the die is maintained in a vacuum or a predetermined non-oxidizing atmosphere. And has the shape of a cap-shaped cover whose lower end is open. The chamber 2 is covered with an outer chamber 1 for maintaining a nitrogen atmosphere so that a mold, a glass material, a molded product and the like are not oxidized even when the chamber 2 is opened at a high temperature.

The material of the chamber 2 should not be affected by the temperature of the chamber 2 when it is cooled.
Further, it is desirable to select a heat-resistant ceramic or the like so as to receive the direct heat from the mold. This time,
The chamber 2 is made of transparent quartz so that the state during molding can be observed from a window (not shown) provided in the outer chamber 1.

The barrel die 3 is supplied with a glass material or a molded product 4.
An opening 3a for taking out the mold 1 is provided, and a plurality of heaters 5 for heating are embedded in the body mold 3 so that the mold can be heated to an arbitrary temperature. I have. The mold is mounted on a fixed shaft 19 mounted on the bottom of the outer chamber 1.

Further, reference numeral 7 denotes an upper die, which is fixed to an upper shaft 8 which is connected to a press drive device 10 for the upper die. When the upper shaft 8 moves up and down as indicated by an arrow A, the pressing operation of the glass material and the raising operation of the upper mold 7 for taking out the molded product 41 can be performed. Further, a lower die press device 11 is attached to the lower surface of the outer chamber 1, and the lower die 6 can be pressurized by driving the lower shaft 9 as shown by the arrow B as necessary. ing.

Inside the outer chamber 1, there is a chamber 2
A chamber opening / closing device 13 for raising and lowering is provided via an arm 12 as shown by an arrow C. Further, a suction hand 14 for sucking and holding the glass material and the molded product 41 with a suction force is provided. Are configured to move horizontally (arrow E) through the arm 15 and the hand vertical drive device 16 so as to be able to advance and retreat to the inside of the trunk mold 3 and to be able to vertically move (arrow D). ing.

In this embodiment, the above-mentioned hand vertical drive device 16 is attached to the shaft 17 of the hand forward and backward movement device 18 attached to the side surface of the outer chamber 1 and in the direction of the above-mentioned arrow E. Under the control of. By such a control operation of the suction hand 14, the supply of the glass material to the molding die and the removal of the molded product 41 can be performed.

Reference numerals 31 and 32 are necessary to keep the atmosphere inside the chamber 2 from the atmosphere inside the outer chamber 1 and maintain the inside of the chamber 2 in a high-temperature nitrogen atmosphere or vacuum. (In this embodiment, the sliding portion of the upper shaft 8 penetrating the wall of the chamber 2 and the opening / closing portion of the chamber 2, that is, the inner wall of the outer chamber 1 at the lower edge of the cap type. An elastic seal member provided at the contact point), for example, a rubber O-ring.
Reference numerals 33 to 35 denote elastic sealing members provided at necessary sealing locations, for example, rubber O-rings, in order to shut off the inside of the outer chamber 1 from the outside atmosphere and keep the atmosphere in a nitrogen atmosphere. It is.

Further, beside these elastic seal members 31, 32, ring-shaped pipes 21, 22 having nitrogen gas outlets 21a, 22a opened, as shown in FIGS. 3 and 2, respectively. The outlet is provided facing the surface of the elastic seal member. The pipe 21 is fixed on the bottom surface of the outer chamber 1, and the pipe 22 is fixed on the upper surface of the inner chamber 2.

In particular, even when the chamber 2 is moved up and down to open and close the lower end of the opening / closing portion, the nitrogen gas can always be blown to the elastic seal members 31 and 32, respectively, even when the chamber 2 comes and goes. Has become. Note that reference numeral 1
a is a groove-shaped mounting seat surface for storing and holding the O-ring 31 as an elastic seal member.

Although not shown in the figure, an exhaust port for evacuating the inside of the chamber 2, cooling of the mold and introduction of nitrogen gas into the chamber 2 are provided.
The outer chamber 1 is provided with a supply and discharge device for supplying the glass material to the suction hand 14 and discharging the molded article 41 taken out by the suction hand 14 to the outside of the outer chamber 1. Is provided.

In such a configuration, an inert cooling fluid such as nitrogen is sprayed on the surfaces of the elastic seal members 31 and 32 exposed to the high-temperature atmosphere in the chamber 2 so that the surface of the elastic seal members is made of a fluid. By forming the protective layer, the elastic seal member can be protected from a high-temperature atmosphere.

When an inert gas such as nitrogen gas is caused to flow over the surface of the elastic sealing member and a gas layer is formed on the surface, gas such as nitrogen gas generally has a very low thermal conductivity. Even if the above-mentioned gas layer is relatively thin, this gas layer effectively functions as a heat insulating layer, and at the same time, the gas flows, thereby producing a cooling effect.

For this reason, even if an elastic sealing member made of rubber, which is inferior in heat resistance to metals or the like, is used, the durability can be greatly improved. Further, by making the flowing gas an inert gas, even if heat is transmitted to the elastic seal member, the risk of the elastic seal member reacting thermally is reduced. For this reason, also from this point, the durability can be greatly extended.

If the temperature of the gas flowing here is lower than the heat-resistant temperature of the elastic sealing member, no particular problem occurs, but if possible, the lower the temperature, the more the cooling effect can be expected, and the durability is high. Can be further improved.

Further, the chamber 2 is separated from the sealing portion in contact with the base of the molding machine main body (in this embodiment, the bottom surface of the outer chamber 1), and the lower edge seal of the chamber 2 is released to form a molding die. Supply of glass materials and moldings 4
When taking out 1, a fluid can be flowed on the surface of the elastic seal member 31 in the chamber 2 exposed to the high-temperature atmosphere in accordance with the timing of exposure to the high-temperature atmosphere.

As described above, when the chamber 2 is released, the surface of the elastic seal member is cooled in a timely manner, and when the chamber 2 is closed, the surface of the elastic seal member cannot be directly blown to be cooled. A portion (in this embodiment, the outer chamber 1 side) can also be cooled (see FIG. 4), and more efficient protection of the elastic seal member can be achieved.

When the chamber 2 is closed,
Since it is not necessary to generate an extra flow of the atmosphere, the thermal influence of the cooling gas on the internal atmosphere is reduced, and the temperature of the atmosphere around the mold can be stabilized. In addition, at the same time, the amount of flowing gas can be greatly reduced.

The members constituting the chamber 2 include:
It is preferable to use a heat-resistant material such as quartz or ceramics. In this case, cooling of the chamber 2 itself becomes unnecessary, and the atmosphere around the mold can be further stabilized. Conversely, when a chamber is made of such a material, it is usually difficult to cool the chamber by, for example, flowing cooling water near a sealing portion of the chamber. Since the members can be protected, a heat-resistant material such as quartz or ceramics can be used as a material for forming the chamber 2.

In this embodiment, the inert cooling fluid such as nitrogen is discharged from the outlets 21a and 22a opened toward the vicinity of the elastic sealing member. A required protective layer can be formed, and it is not necessary to direct excess gas to the other area in the chamber 2, and the elastic sealing member can be effectively protected without disturbing the atmosphere around the mold. become. Note that the shape of the outlet here may be an annularly continuous slit shape or a shape intermittently opened in the longitudinal direction of the cooling pipe, as long as gas can be applied to the entire surface of the elastic seal member. It may have a hole shape.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) Next, an embodiment of the present invention will be described more specifically with reference to FIGS. Here, a biconvex lens having a diameter of 20 mm and a center thickness of 5.5 mm was molded from a glass material having a molding temperature of 600 ° C.

First, after replacing each atmosphere of the outer chamber 1 and the chamber 2 with a nitrogen atmosphere, the chamber opening / closing device 13 is set so that the suction hand 14 is inserted into the opening 3a.
And the upper mold driving device 10 are operated, and the chamber 2 and the upper mold 7 are operated.
Is raised. Next, the glass material in the outer chamber 1 is introduced using a supply / unloader (not shown), and is sucked by the suction hand 14. And hand forward / reverse device 1
8 is advanced, the suction hand 14 is advanced into the opening 3a, the hand vertical drive device 16 is moved downward, and the glass material suctioned by the suction hand 14 is placed on the lower mold 6,
Next, the hand vertical driving device 16 is moved upward, and the shaft 17 is moved backward by the hand forward / backward moving device 18.

Next, the chamber opening / closing device 13 is lowered, and the lower end of the chamber 2 is pressed against the O-ring 31.
The inside of the chamber 2 is sealed. Then, the heater 5 is energized to start heating the mold, and at the same time, the pipe 2 is heated.
Nitrogen gas at a temperature of 25 ° C., which is almost the same as the room temperature, is supplied to the nitrogen gas outlets 21 and 22 and the nitrogen gas outlet holes 21 a and 21
2a, nitrogen gas is supplied to O-rings 31 and 32, respectively.
Then, a very small amount was sprayed (the state shown in FIGS. 2 and 3).

When the temperature of the lower mold 6 and the upper mold 7 reaches 600 ° C., which is the molding temperature of the glass material used in this embodiment, the upper mold 7 is moved to the lower side of the body mold 3 with the lower surface of the flange surface. The glass material was lowered until it hit the upper surface, and the glass material was press-formed so as to follow the shapes of the lower mold 6 and the upper mold 7. Immediately thereafter, the power supply to the heater 5 is stopped, and nitrogen gas is blown through the nitrogen gas inlet (not shown) to the lower mold 6, the upper mold 7, and the body mold 3 to start cooling. In addition, the lower die press device 11 is operated and the lower shaft 9 is moved to the lower die 6 so that the molded product 41 does not separate from the molding surface of the lower die 6 and the molding surface of the upper die 7 due to the contraction of the cooling. Pressed.

The lower die 6, the upper die 7, and the molded product 41 are
When the temperature reaches 450 ° C., the cooling is stopped, and the temperature of the molded article 41 is maintained, for example, for about 10 seconds until the temperature of the molded article 41 becomes uniform.
The upper mold 7 and the chamber 2 are raised, the molded article 41 is taken out by the suction hand 14, and the glass material is again sucked by the suction hand 1.
At 4, it is supplied onto the lower mold 6. In this way, the above-described steps were repeated, and a molded product 41 was sequentially obtained.

The temperature in the vicinity of the mold inside the chamber 2 in this molding is controlled by the chamber 2
, Which is shielded from the atmosphere near the room temperature,
In addition, a small amount of gas flows out of the pipes 21 and 22 and flows out in a direction opposite to the direction of the molding die, so that the uniformity is maintained except for a very short time during cooling. as a result,
There was almost no difference in the temperature distribution from press molding to removal of the molded article 41, and the molded article 41 having excellent transferability of the shape of the molding surface could be obtained.

The cycle for obtaining one molded article of this molding is 6 minutes, and the maximum temperature of the nitrogen gas in the chamber 2 reaches 550 ° C., which is slightly lower than the molding temperature. there were. It should be noted that nitrogen gas was continuously supplied from the nitrogen gas blowing holes 21a and 22a.

As a result, if nitrogen gas is not flowed, the temperature of the O-rings 31 and 32 exceeds the heat-resistant temperature of the rubber used as the material of the O-rings 31 and 32: 150 ° C. in two-shot or three-shot molding. For sealing,
Although it did not endure practical use, as described above, by flowing nitrogen gas, the surface temperature of the O-rings 31 and 32 remained at 130 ° C. at the maximum, and it became possible to sufficiently endure practical use.

(Second Embodiment) Next, another embodiment of the present invention performed using the apparatus used in the above embodiment will be described with reference to FIGS. Here, using a glass material having a molding temperature of 550 ° C., an optical element having a flat plate shape with a diameter of 25 mm and a thickness of 3 mm and a fine ring-shaped pattern drawn on the surface was formed. .

Here, the major difference from the first embodiment is that, similarly to the first embodiment, when press molding is performed in a nitrogen atmosphere, the glass material and the surface of the molding surface of the molding die are formed. In order to prevent the problem that nitrogen gas in the atmosphere is trapped between fine patterns and traces of the gas remain on the surface of the completed optical element,
Press molding must be performed in a vacuum.

Therefore, first, the same operation as in the first embodiment is performed, a glass material is placed on the lower mold 6, the chamber 2 is lowered, and the internal atmosphere of the chamber 2 is changed to the external chamber 1. In order to cut off the temperature of the nitrogen atmosphere 32 from the internal atmosphere, the heater 5 is energized, and the heating of the mold and the glass material is started.
2 was supplied with nitrogen gas, and a slight amount of nitrogen gas was blown into the nitrogen atmosphere 32.

Next, when the temperature of the molding die reaches 550 ° C., which is the molding temperature of the glass material, the supply of nitrogen gas to the pipe 22 is stopped, and immediately the nitrogen gas inside the chamber 2 is evacuated to the vacuum exhaust port ( (Not shown). The pressure inside the chamber 2 was reduced to 2 × 10 ⁻² Torr over about 10 seconds, and then the upper mold 7 was immediately lowered to press-mold the glass material. At the same time that the lower surface of the flange surface of the upper die 7 abuts against the upper surface of the body die 3, the power supply to the heater 5 is stopped, and nitrogen gas is passed through the nitrogen gas inlet (not shown).
Blowing is performed on the upper mold 7 and the body mold 3 to start cooling of the glass molded product and the like, and the molding surface of the lower mold 6 and the molding surface of the upper mold 7 are separated from the molded product 41 by contraction of the molded product due to the cooling. The lower die press device 11 was operated so as not to be stuck, and the lower shaft 9 was pressed against the lower die 6. The lower die 6, the upper die 7, the molded product 41
When the temperature of the molded product reached 400 ° C., the cooling of the molded product and the like was stopped, and the temperature of the molded product 41 was maintained for about 5 seconds until the temperature of the molded product 41 became uniform.

At the timing of raising the chamber 2, nitrogen gas is supplied to the pipe 21 as shown in FIG.
1 and a low-temperature nitrogen gas film is formed on the surface of the O-ring 31. The nitrogen gas heated during the cooling of the mold inside the chamber 2 does not directly hit the surface of the O-ring 31. I did it. Further, a nitrogen gas was supplied to the pipe 22 simultaneously with the start of cooling to the O-ring 32 to cool the surface of the O-ring 32.

Then, while the supply of nitrogen gas to the pipes 21 and 22 is maintained, the molded product 41 is taken out by the suction hand 14, and the glass material is again supplied to the molding surface of the lower die 6 by the suction hand 14. Then, the chamber 2 was closed. At this point, the supply of the nitrogen gas to the pipe 21 is stopped. In this way, the above-described steps were repeated, and a molded product 41 was sequentially obtained.

As described above, in this embodiment, since the nitrogen gas is intermittently blown to the O-rings 31, 32, the amount of nitrogen gas used can be greatly reduced. Since the factor of disturbing the atmosphere inside the chamber 2 was reduced by half compared to the first embodiment, the molding 4
1 had less effect on the temperature distribution.

Although the nitrogen gas was blown onto the O-ring 32 intermittently in order to evacuate it, the molding temperature was slightly lower than in the first embodiment. Since the contact time with the nitrogen gas atmosphere is short, the temperature of the O-ring 32 does not exceed 125 ° C.
The nitrogen gas was blown onto the ring 31 only when the chamber 2 was separated from the O-ring 31. However, during heating and cooling of the mold, the O-ring 31 was below the mold, and the molding temperature was lowered. It may be low, so the O-ring 31
Since the temperature of the gas itself is relatively hard to rise and the heated nitrogen gas inside the chamber 2 hits, the surface is protected by the low-temperature nitrogen gas film as described above.
The temperature of the O-ring 31 did not exceed 130 ° C. at the maximum, and both the O-rings 31 and 32 had sufficient durability to cope with continuous and practical production.

Third Embodiment Next, still another embodiment of the present invention will be described with reference to FIG. The difference between the device used in this embodiment and the device used in the first embodiment is as follows.
As shown in FIG. 5, the O-ring 3 at the bottom of the outer chamber 1
1 is that a cooling water passage 1b through which cooling water passes is provided directly below the mounting seat surface 1a.

Using such an apparatus, the same lens as that of the first embodiment is continuously produced under the same conditions,
Although the temperature of the ring 31 was measured and the durability was examined, the temperature inside the O-ring 31 did not exceed 100 ° C. due to the cooling effect of the cooling water in the cooling water passage 1b, and the chamber 2 was raised. During the operation, the surface temperature of the O-ring 31 is 1
The temperature did not exceed 15 ° C., and no problem occurred in durability in normal use.

In the above embodiment, a heating means such as a heater incorporated in the barrel 3 is used as a heating means, but a heating means which can be used in the present invention is However, the present invention is not limited to this. For example, a heating unit using radiation from around the mold or a heating unit using high frequency may be used, and the same effect as described above can be obtained by such a heating unit.

[0053]

As described above, according to the present invention,
When using an elastic seal member, such as an O-ring seal, used in a high-temperature environment, an inert cooling fluid such as nitrogen is caused to flow on the surface of the seal member exposed to a high-temperature atmosphere, and the fluid is applied to the surface of the seal member. By forming the protective layer, it has become possible to obtain durability sufficient for practical use for a long time.

Further, according to the present invention, the temperature of the atmosphere around the mold is stabilized by flowing a cooling fluid onto the surface of the seal member exposed to the high-temperature atmosphere in synchronization with the timing of exposure to the high-temperature atmosphere. However, at the same time, the amount of flowing gas can be greatly reduced.

Further, according to the present invention, since the chamber is made of a heat-resistant material such as quartz or ceramics, cooling of the chamber itself becomes unnecessary, and the atmosphere around the mold is reduced.
More stable, and conversely,
When a chamber is made of such a material, it is generally difficult to cool the vicinity of the seal portion of the chamber by flowing cooling water or the like. Since the material can be protected, a heat-resistant material such as quartz or ceramics can be used as a material for forming the chamber.

Further, according to the present invention, an inactive fluid such as nitrogen is caused to flow out from an outlet continuously provided in the vicinity of the seal member, so that an unnecessary cooling gas does not flow except in the vicinity of the seal member. Thus, the seal member can be effectively protected without disturbing the atmosphere around the mold.

Furthermore, according to the present invention, by simultaneously cooling the mounting seat surface of the seal member from the inside, it is possible to suppress the temperature rise of the seal member itself, and the gas to be blown cools only the surface of the seal member. In addition, since it is only necessary to protect the seal member, it is possible to further increase the durability of the seal member.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an apparatus used in the present invention.

FIG. 2 is a view of one embodiment of spraying a fluid to a seal member used in the present invention.

FIG. 3 is a view of another embodiment of spraying a fluid to a seal member used in the present invention.

FIG. 4 is a diagram illustrating a state of spraying a fluid to a seal member used in the present invention.

FIG. 5 is a diagram illustrating a method of cooling a seal member used in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Outer chamber 1a Sealing member mounting seat surface 1b Cooling water channel 2 Chamber 5 Heater 6 Lower die 7 Upper die 13 Chamber opening / closing device 21, 22 Ring-shaped piping 21a Nitrogen gas blowing hole 22a Nitrogen gas blowing slit 31, 32 O-ring

Claims (8)

[Claims] When a glass material in a heat-softened state is press-formed by a mold having at least one set of an upper mold and a lower mold, a vacuum or a required non-oxidizing material is formed in a chamber accommodating the mold. In a press forming apparatus for maintaining an atmosphere and shutting off an atmosphere outside a chamber, a cooling means for blowing a cooling fluid against an elastic seal member provided at a sealing portion of the chamber for shutting off the atmosphere is provided. A protection mechanism for an elastic seal member, which is provided. 2. The protection mechanism for an elastic seal member according to claim 1, wherein the cooling means includes a cooling fluid ejection port inside the chamber and near the elastic seal member. . 3. The cooling means sprays the cooling fluid on a portion exposed to an atmosphere in the chamber when the opening / closing portion is opened, with respect to an elastic sealing member provided at the opening / closing portion of the chamber. The protection mechanism for an elastic seal member according to claim 1 or 2, wherein the ejection ports are arranged as described above. 4. The elastic seal member according to claim 1, wherein the cooling fluid is an inert gas, preferably a cooling medium of the same type as the non-oxidizing atmosphere. Protection mechanism. 5. The protection mechanism according to claim 1, wherein the elastic seal member is made of an elastic material such as rubber. 6. A cooling device according to claim 1, further comprising a heat transfer type cooling means adjacent to the mounting seat for the elastic seal member. Protection mechanism for the elastic seal member. 7. When a glass material in a heat-softened state is press-molded by a mold having at least one pair of an upper mold and a lower mold, a vacuum or a required non-oxidizing material is formed in a chamber accommodating the mold. In a press molding apparatus that maintains the atmosphere and shuts off the atmosphere outside the chamber, the cooling fluid is sprayed on an elastic seal member provided at a sealing portion of the chamber for shutting off the atmosphere, A method for protecting an elastic seal member, comprising forming a protective layer against high temperature on the surface of the elastic seal member. 8. At the opening / closing portion of the chamber, supply of a glass material to the molding die and removal of a molded product after press molding are performed on the elastic seal member provided for sealing the location. When, for example, the elastic seal member is exposed to a high temperature at the time of performing, a cooling fluid is sprayed on the elastic seal member to form a protective layer on the surface of the elastic seal member against the high temperature. The method for protecting an elastic seal member according to claim 7.