JP7159937B2 - Molding device and method for manufacturing glass article - Google Patents

Description

The present invention relates to a mold apparatus and a method for manufacturing a glass article.

BACKGROUND ART Conventionally, as a method for manufacturing a glass article, for example, as disclosed in Patent Document 1, a method of press-molding a mass of molten glass (glass gob) using a mold is known. The mold disclosed in Patent Document 1 has a pressing surface including concave portions, and by using this mold, a glass article having convex portions on the bottom surface can be manufactured. In order to prevent air from being entrapped in the concave portion of the press surface when manufacturing a glass article using such a mold, an air vent hole is formed in the concave portion.

JP-A-09-328321

When the conventional mold has a gas discharge path for discharging gas such as air, as in the recess on the pressing surface of the above-mentioned conventional mold, the glass flows into the gas discharge path in the recess, so that the glass article has a gas discharge path. A relatively large protrusion may be formed along the shape of the . Such relatively large protrusions and traces of missing protrusions can be a factor in degrading the appearance quality of the glass article.

The present invention has been made in view of such circumstances, and its object is to provide a mold apparatus and a method for manufacturing a glass article that can easily improve the appearance quality of a glass article having convex portions on the outer surface. That's what it is.

A mold apparatus for solving the above problems is a mold apparatus that includes a mold having a press surface that includes a recess and is used for press molding of glass, wherein the mold includes a gas that discharges the gas in the recess. a discharge path, the gas discharge path having an inlet that opens into the recess and allows the gas in the recess to flow in, and the mold device has a tip disposed in the gas discharge path and the tip of the shaft-shaped member is arranged at the end of the gas discharge passage on the inlet side so as to be separated from the inner wall surface of the gas discharge passage.

According to this configuration, the tip of the shaft-shaped member of the mold device is arranged at the end of the gas discharge passage on the inlet side so as to be spaced apart from the inner wall surface of the gas discharge passage, so that the tip of the shaft-shaped member A relatively narrow channel can be formed between the outer peripheral surface of the gas discharge channel and the inner wall surface of the gas discharge channel. As a result, it is possible to prevent the glass filled in the concave portion of the pressing surface of the mold from entering the gas discharge path. Therefore, unnecessary projections due to the gas discharge path of the mold are less likely to be formed on the surface of the convex portion of the glass article. Although it is possible to form a narrow flow path by reducing the diameter of the gas discharge path itself, the total area of the flow path must be relatively small compared to the above configuration. becomes difficult to discharge. According to the above configuration, while the flow path is relatively narrow, it is easy to secure the total cross-sectional area of the flow path that allows the gas in the recessed portion to flow efficiently into the gas discharge path, and unnecessary Protrusions are difficult to form. In addition, since the tip of the shaft-shaped member is separated from the gas discharge path, the heat of the tip of the shaft-shaped member can be released to the outside through the gas discharge path. The temperature is lower than other parts of the mold apparatus, and the effect of cooling the glass can be enhanced.

The separation of the tip of the shaft-shaped member from the inner wall surface of the gas discharge passage is not limited to the case where the outer peripheral surface of the tip of the shaft-shaped member is separated from the inner wall surface of the gas discharge passage over the entire circumference. , and the case where a part of the outer peripheral surface of the tip of the shaft-shaped member is in contact with the inner wall surface of the gas discharge passage and the other part is separated.

In the mold apparatus described above, it is preferable that the gas discharge path has a discharge port that opens to the outer surface of the mold, and that the shaft-like member has a protruding portion that protrudes from the discharge port.
According to this configuration, the temperature of the shaft-like member can be further lowered by cooling the protruding portion of the shaft-like member of the mold device with, for example, the outside air. Thereby, the effect of cooling the glass in contact with the tip surface of the shaft-shaped member can be enhanced. That is, the contact of the glass with the tip end surface of the shaft-like member reduces the fluidity of the glass, so that the entry of the glass into the gas discharge passage can be further suppressed.

Preferably, the mold apparatus further includes a cooling mechanism for cooling the projecting portion of the shaft-like member.
According to this configuration, the projecting portion of the shaft-shaped member in the mold device is forcibly cooled by the cooling mechanism of the mold device, thereby further enhancing the effect of cooling the glass in contact with the tip surface of the shaft-shaped member. be able to.

The mold apparatus preferably further includes a suction mechanism for forcibly discharging the gas in the recess through the gas discharge path.
According to this configuration, the glass can be quickly filled into the concave portion of the mold. When the shaft-shaped member is forcibly cooled by the cooling mechanism, the concave portion of the mold can be quickly filled with the glass, and the fluidity of the glass is lowered, so that the glass can be reliably filled in the concave portion. It can be filled, and the formation of unnecessary protrusions caused by the gas discharge path of the mold on the surface of the convex portion of the glass article becomes difficult.

In the above-described mold apparatus, the shaft-shaped member has a mounting portion that is mounted in the gas discharge path, and the mounting portion guides the gas in the gas discharge path in a direction to discharge the gas to the outside of the mold. It is preferable to have gas flow passages.

According to this configuration, maintenance of the mold can be performed by, for example, detaching the shaft-like member from the mold using the shaft-like member mounting portion of the mold apparatus.
A method for manufacturing a glass article that solves the above problems obtains a glass article having convex portions formed corresponding to the concave portions of the mold by press-molding glass using the mold apparatus.

ADVANTAGE OF THE INVENTION According to this invention, the appearance quality of the glass article which has a convex part in an outer surface can be improved easily.

1 is a schematic cross-sectional view showing a mold device of an embodiment; FIG. It is a cross-sectional view showing the main part of the mold device. (a) is a plan view showing a main part of a mold device, and (b) is a plan view showing a main part of a mold device of a modification. (a) And (b) is a top view which shows the principal part of the metal mold|die apparatus of a modification.

An embodiment of a mold apparatus and a method for manufacturing a glass article will be described below with reference to the drawings. In the drawings, for convenience of explanation, part of the configuration may be exaggerated or simplified. Also, the dimensional ratio of each part may differ from the actual one.

As shown in FIG. 1, a mold device 11 is used for press molding glass G, and includes a lower mold 12 and an upper mold 13 . The lower die 12 of the die device 11 has a first pressing surface P1, and the upper die 13 of the die device 11 has a second pressing surface P2. A cavity of the mold device 11 is formed by a first press surface P1 and a second press surface P2.

A first pressing surface P<b>1 of the lower die 12 includes a recess 14 . By filling the concave portions 14 of the first pressing surface P1 with the glass G, a glass article having convex portions on the outer surface can be obtained.

As shown in FIG. 2 , the lower mold 12 of the mold device 11 has a gas discharge path 15 . The gas discharge path 15 of the lower mold 12 has an inlet 15a into which the gas in the recess 14 of the lower mold 12 flows, and an outlet 15b that opens to the bottom surface of the lower mold 12 . In addition, in the gas discharge path 15 of the present embodiment, the inner diameter of the inlet 15a side is formed smaller than the inner diameter of the discharge port 15b side. Alternatively, for example, the inner diameter on the side of the outlet 15b may be smaller than the inner diameter on the side of the inlet 15a.

The upper mold 13 of the mold apparatus 11 of this embodiment has a three-part structure consisting of a first upper mold 13a, a second upper mold 13b, and a third upper mold 13c. Note that the division structure of the upper mold 13 can be appropriately changed according to the shape of the glass product to be molded.

As shown in FIGS. 2 and 3( a ), the mold device 11 further includes a shaft member 16 provided corresponding to the gas discharge path 15 of the lower mold 12 . The shaft-like member 16 has a tip portion 16 a arranged inside the gas discharge path 15 of the lower mold 12 . In addition, in FIG. 3, the tip portion 16a (tip surface) of the shaft-like member 16 is shown in a pear-skin pattern.

A tip portion 16 a of the shaft-like member 16 is arranged at an end portion of the gas discharge passage 15 on the side of the inlet 15 a so as to be separated from the inner wall surface of the gas discharge passage 15 . 2, the gas in the recess 14 of the lower die 12 can flow between the inner wall surface of the gas discharge path 15 and the tip 16a of the shaft-like member 16. .

The tip portion 16a of the shaft-like member 16 of this embodiment has a solid structure. The area of the tip surface of the shaft-shaped member 16 is preferably within a range of 10% or more and 90% or less, more preferably 30% or more and 70%, of the opening area of the inlet 15a of the gas discharge passage 15. Within the following range. The tip surface of the tip portion 16 a of the shaft-like member 16 is preferably formed so as to be flush with the first pressing surface P 1 surrounding the inlet 15 a of the gas discharge passage 15 .

The shaft-like member 16 of the mold device 11 has a protruding portion 16 b protruding from the opening of the gas discharge passage 15 of the lower mold 12 and a mounting portion 16 c mounted inside the gas discharge passage 15 . The attachment portion 16c of the shaft-like member 16 is provided between the tip portion 16a and the projecting portion 16b. The mounting portion 16c of the present embodiment is composed of a male screw portion and is attached to the gas discharge passage 15 by being screwed into a female screw portion formed in the gas discharge passage 15 of the lower die 12 .

The shaft-like member 16 has a gas flow path 17 that guides the gas in the gas discharge path 15 of the lower mold 12 in a direction to discharge it to the outside of the lower mold 12 . The gas flow passage 17 of the shaft-like member 16 has a groove portion 18 into which the gas in the gas discharge passage 15 of the lower die 12 flows, and a through hole 19 into which the gas flows from the groove portion 18 . The through-hole 19 of the gas flow passage 17 has an outflow port 19a that opens to the projecting portion 16b of the shaft-like member 16. As shown in FIG.

The shaft-like member 16 can be made of a metal material that is the same as or different from the metal material of the mold.
As shown in FIG. 2, the mold device 11 further includes a cooling mechanism 20 that cools the projecting portion 16b of the shaft-like member 16. As shown in FIG. As the cooling mechanism 20, for example, a blower fan, a refrigerant circulation mechanism, or the like can be used. The mold apparatus 11 further includes a suction mechanism 21 for forcibly discharging the gas in the recess 14 of the lower mold 12 through the gas discharge path 15 of the lower mold 12 . For example, an electric pump can be used as the suction mechanism 21 .

Examples of glass articles include trays, containers, turntables for cooking appliances, substrates for thin film lamination such as for reflectors, and window materials.
It is preferable that the glass G used for the glass article for these purposes has heat resistance. As the heat-resistant glass, for example, an extremely low-expansion crystallized glass (glass ceramics) having an average linear thermal expansion coefficient of about -10 to +30×10 ^-7 /°C at 30 to 750°C can be used. The composition of the heat-resistant glass is, in mass %, SiO ₂ : 55 to 75%, Al ₂ O ₃ : 20.5 to 27%, Li ₂ O: 2% or more, TiO ₂ : 1.5 to 3%, TiO ₂ +ZrO ₂ : 3.8 to 5% and SnO ₂ : 0.1 to 0.5% are preferably included.

The heat-resistant glass used in the glass article may be, for example, borosilicate glass. The glass composition of the borosilicate glass is SiO ₂ : 70 to 85%, Al ₂ O ₃ : 0 to 5%, B ₂ O ₃ : 10 to 20%, Na ₂ O: 2 to 10%, K ₂ O: It is preferable to contain 0 to 5%.

Next, a method for manufacturing a glass article will be described together with the main functions of the mold apparatus 11 described above.
The method for manufacturing a glass article is a method for obtaining a glass article having convex portions formed corresponding to concave portions 14 of the lower mold 12 by press-molding the glass G using the mold device 11 . In the method for manufacturing a glass article, first, the amount of glass gobs required for the glass article is placed on the first pressing surface P1 of the lower mold 12, and the upper mold 13 is lowered to press the first pressing surface P1 of the lower mold 12. The glass gob is pressed between the second pressing surface P2 of the upper mold 13 and the second pressing surface P2.

As indicated by a two-dot chain line in FIG. 2, when the glass G enters the recess 14 of the first pressing surface P1 of the lower mold 12, the gas in the recess 14 is discharged through the gas discharge path 15. As shown in FIG. While the gas in the concave portion 14 is discharged in this way, the glass G is filled in the concave portion 14 . At this time, since the mold device 11 of the present embodiment includes the suction mechanism 21, the gas in the recess 14 can be forcibly discharged.

Here, the tip portion 16 a of the shaft-like member 16 of the mold device 11 is arranged apart from the inner wall surface of the gas discharge passage 15 at the end of the gas discharge passage 15 on the inlet 15 a side. According to this configuration, a relatively narrow gas flow path can be formed between the outer peripheral surface of the tip portion 16 a of the shaft-like member 16 and the inner wall surface of the gas discharge path 15 . Therefore, it is possible to prevent the glass G filled in the concave portion 14 of the first pressing surface P<b>1 from entering the gas discharge path 15 .

Further, the shaft-like member 16 of the mold device 11 of this embodiment has a protruding portion 16b that protrudes from the discharge port 15b of the gas discharge path 15. As shown in FIG. The temperature of the shaft-like member 16 can be further lowered by cooling the projecting portion 16b of the shaft-like member 16 with, for example, the outside air. Thereby, the effect of cooling the glass G in contact with the tip surface of the shaft-like member 16 can be enhanced. That is, the contact of the glass G with the tip surface of the shaft-like member 16 reduces the fluidity of the glass G, so that the entry of the glass G into the gas discharge passage 15 can be further suppressed. In this embodiment, since the shaft-like member 16 is forcibly cooled by the cooling mechanism 20 of the mold device 11, the effect of cooling the glass G in contact with the tip surface of the shaft-like member 16 can be further enhanced. .

In the method for manufacturing a glass G article, after press molding of the glass G is completed, the upper mold 13 is lifted and the glass article is taken out from the lower mold 12 . By manufacturing the glass article in this manner, the projections formed due to the gas discharge path 15 can be made extremely small.

Next, the operation and effects of this embodiment will be described.
(1) The mold device 11 has a lower mold 12 which is a mold having a first pressing surface P1 including a recess 14, and is used for press molding of the glass G. As shown in FIG. The lower mold 12 of the mold device 11 has a gas discharge path 15 for discharging the gas in the concave portion 14 of the first pressing surface P1. The gas discharge path 15 of the lower mold 12 has an inlet 15a that opens into the recess 14 of the first pressing surface P1 and allows the gas in the recess 14 to flow in. The mold device 11 further includes a shaft-like member 16 having a distal end portion 16 a disposed within the gas discharge path 15 . A tip portion 16 a of the shaft-like member 16 in the mold device 11 is arranged apart from the inner wall surface of the gas discharge passage 15 at the end portion of the gas discharge passage 15 on the inlet 15 a side.

According to this configuration, the tip portion 16a of the shaft-shaped member 16 of the mold device 11 is arranged away from the inner wall surface of the gas discharge passage 15 at the end of the gas discharge passage 15 on the side of the inlet 15a. A relatively narrow passage can be formed between the outer peripheral surface of the tip portion 16 a of the shaft-like member 16 and the inner wall surface of the gas discharge passage 15 . Thereby, it is possible to prevent the glass G filled in the concave portion 14 of the first pressing surface P<b>1 of the lower mold 12 from entering the gas discharge path 15 . Therefore, unnecessary protrusions caused by the gas discharge path 15 of the lower mold 12 are less likely to be formed on the surface of the convex portion of the glass article. Therefore, it is possible to easily improve the appearance quality of a glass article having protrusions on the outer surface.

As in the present embodiment, by arranging the tip portion 16a of the shaft-shaped member 16 away from the inner wall surface of the gas discharge passage 15, the gas is discharged from the entire inner periphery of the inlet 15a of the gas discharge passage 15. be able to. That is, by utilizing the arrangement of the tip portion 16a of the shaft-shaped member 16 in the mold device 11 to form a portion with a narrow flow path width at the inlet 15a of the gas discharge path 15, the glass in the gas discharge path 15 Intrusion of G can be suppressed, and the gas flow rate can be easily ensured.

Furthermore, since the tip portion 16a of the shaft-like member 16 is separated from the gas discharge path 15, the heat of the shaft-like member 16 can be efficiently released to the outside through the gas discharge path 15, so that the shaft-like member 16 The tip portion 16a of is lower in temperature than other portions of the mold apparatus 11, and the effect of cooling the glass G can be enhanced.

In particular, when the outer peripheral surface of the tip portion 16a of the shaft-like member 16 is separated from the inner wall surface of the gas discharge passage 15 over the entire circumference as in the present embodiment, the tip portion 16a of the shaft-like member 16 is in contact with the inner wall surface of the gas discharge passage 15, the cooling effect can be easily obtained.

(2) In the mold apparatus 11, the gas discharge passage 15 of the lower mold 12 has a discharge port 15b that opens to the outer surface of the lower mold 12, and the shaft-like member 16 protrudes from the discharge port 15b of the gas discharge passage 15. It is provided with a projecting portion 16b. In this case, the temperature of the shaft-like member 16 can be further lowered by cooling the projecting portion 16b of the shaft-like member 16 with, for example, the outside air. Thereby, the effect of cooling the glass G in contact with the tip surface of the shaft-like member 16 can be enhanced. That is, the contact of the glass G with the tip surface of the shaft-like member 16 reduces the fluidity of the glass G, so that the entry of the glass G into the gas discharge passage 15 can be further suppressed. Therefore, it becomes easy to further improve the appearance quality of the glass article.

(3) The mold device 11 further includes a cooling mechanism 20 that cools the projecting portion 16b of the shaft-like member 16. As shown in FIG. In this case, since the projecting portion 16b of the shaft-like member 16 in the mold device 11 is forcibly cooled by the cooling mechanism 20 of the mold device 11, the glass G in contact with the tip surface of the shaft-like member 16 is cooled. The effect can be further enhanced.

(4) The mold device 11 further includes a suction mechanism 21 for forcibly discharging the gas in the recess 14 of the lower mold 12 through the gas discharge path 15 of the lower mold 12 . In this case, the recess 14 of the lower mold 12 can be quickly filled with the glass G. Therefore, for example, the productivity of glass articles can be increased. In addition, even if the productivity is improved in this way, the glass G can be prevented from entering the gas discharge path 15 of the lower mold 12 by the shaft-like member 16 of the mold device 11, thereby improving the appearance quality of the glass article. can be maintained.

(5) The shaft-like member 16 of the mold device 11 has a mounting portion 16c mounted inside the gas discharge passage 15. As shown in FIG. The mounting portion 16 c of the shaft-shaped member 16 has a gas flow passage 17 that guides the gas in the gas discharge passage 15 in a direction to discharge it to the outside of the lower die 12 . In this case, maintenance of the lower mold 12 can be performed by, for example, detaching the shaft-like member 16 from the lower mold 12 using the attachment portion 16c of the shaft-like member 16 .

(Change example)
This embodiment can be implemented with the following modifications. This embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

The structure of the attachment portion 16c for attaching the shaft-like member 16 of the mold device 11 to the lower mold 12 is not limited to the screwing structure described above. A structure in which the shaft member 16 is engaged with the lower die 12 or a structure in which the shaft member 16 is fitted into the gas discharge path 15 of the lower mold 12 may be used. Also, the shaft-like member 16 of the mold device 11 can be attached by joining it to the lower mold 12 by welding or the like, for example.

- The protruding portion 16b of the shaft-like member 16 of the mold device 11 may be omitted, and the entire shaft-like member 16 may be arranged in the gas discharge path 15.
The projecting portion 16 b of the shaft-like member 16 of the mold device 11 may be omitted, the entire shaft-like member 16 may be arranged in the gas discharge passage 15 , and the shaft-like member 16 may be cooled by the cooling mechanism 20 .

・As shown in FIG. 3(b), in the mold device 11, the structure of the tip portion 16a of the shaft-like member 16 is not limited to a solid structure. It may be a hollow structure having

- As shown in FIGS. 4(a) and 4(b), the tip 16a of the shaft-like member 16 may be divided into a plurality of parts. Moreover, the shape of the tip surface of the shaft-like member 16 is not limited to a circular shape, and may be, for example, a polygonal shape.

- As shown in FIG.4(b), also about the cross-sectional shape of the gas discharge path 15, it is not limited to circular shape, Polygonal shape etc. may be sufficient.
- It is also possible to omit the suction mechanism 21 of the mold device 11 and push out the gas in the concave portion 14 of the lower mold 12 by the pressing pressure of the upper mold 13 that presses the glass G into the concave portion 14 .

- The cooling mechanism 20 of the mold device 11 can be omitted.
- The mold having the concave portion 14 and the gas discharge path 15 is not limited to the lower mold 12 and may be the upper mold 13 . In this case, the tip portion 16 a of the shaft-like member 16 may be arranged inside the gas discharge path 15 of the upper die 13 .

DESCRIPTION OF SYMBOLS 11... Mold apparatus, 12... Lower mold, 13... Upper mold, 14... Concave part, 15... Gas discharge path, 15a... Inflow port, 15b... Discharge port, 16... Shaft-shaped member, 16a... Tip part, 16b... Protrusion Part 16c... Mounting part 17... Gas flow path 20... Cooling mechanism 21... Suction mechanism G... Glass P1... First pressing surface.

Claims (4)

A mold apparatus comprising a mold having a press surface including a concave portion and used for press molding of glass,
The mold has a gas discharge path for discharging the gas in the recess,
The gas discharge path has an inlet that opens into the recess and allows the gas in the recess to flow in,
The mold device further comprises a shaft-shaped member having a tip disposed in the gas discharge path,
the tip portion of the shaft-shaped member is arranged at an end portion of the gas discharge passage on the inlet side so as to be separated from the inner wall surface of the gas discharge passage ;
The gas discharge path has a discharge port that opens to the outer surface of the mold,
The shaft-shaped member has a protrusion that protrudes from the discharge port,
A mold apparatus, further comprising a cooling mechanism for cooling the projecting portion of the shaft-shaped member . 2. The mold apparatus according to claim 1 , further comprising a suction mechanism for forcibly discharging gas in said recess through said gas discharge path. The shaft-shaped member has a mounting portion mounted in the gas discharge path,
3. The mold apparatus according to claim 1, wherein said mounting portion has a gas flow path for guiding gas in said gas discharge path to the outside of said mold. A glass article having convex portions formed corresponding to the concave portions of the mold is obtained by press-molding glass using the mold apparatus according to any one of claims 1 to 3 . , a method for manufacturing a glass article.

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