JP3206951B2 - Optical element molding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical element molding apparatus for press-molding a heat-softened glass material by a pair of molding dies, and in particular, performs pressure molding while aligning the molding die with the glass material. The present invention relates to a molding device for an optical element.

[0002]

2. Description of the Related Art Conventionally, there has been known an apparatus in which a heat-softened glass material is inserted between an upper mold and a lower mold and then pressed by both upper and lower molds to form an optical element such as a lens. For example, Japanese Laid-Open Utility Model Application No. 3-18136 discloses the following invention.

In the above invention, when a glass material placed in a glass conveying member is pressed by an upper mold and a lower mold, the centering member is tapered into a cylindrical portion formed in the glass conveying member as the lower mold is raised. The glass material is pressurized in a state where the outer diameter of the centering member and the cylindrical portion are fitted and the lower mold and the glass conveying member are aligned and positioned to form a press lens. Things.

[0004]

However, the above conventional invention has the following problems. That is, as shown in FIG. 11, the transfer member 53 on which the glass 52 held by the transfer arm 51 is placed is centered in the cylindrical portion formed in the transfer member 53 together with the rise of the lower mold 54 during press molding. When the member 55 is inserted, if the clearance between the conveying member 53 and the centering member 55 is small, the air is wrapped inside, and the conveying member 53 is lifted obliquely, so that there is a problem that positioning is not accurately performed. .

Accordingly, the present invention has been made in view of the above-mentioned problems in the prior art, and it is an object of the present invention to provide an optical element capable of preventing displacement between a mold and a conveying member and, in particular, preventing air from being wrapped. The purpose is to provide a molding device.

[0006]

According to a first aspect of the present invention, there is provided an apparatus for molding an optical element, comprising: a glass material installation section for installing a glass material; and a glass material installation section provided below the glass material installation section. And a glass transport member having a cylindrical portion provided coaxially, an upper die and a lower die disposed coaxially opposed to each other, and a transport arm for transporting the glass transport member between the upper die and the lower die. In the optical element molding apparatus having: a centering portion for centering the glass conveying member and the lower mold by fitting to the cylindrical portion of the glass conveying member; and the centering portion fits to the cylindrical portion. An exhaust portion having a groove formed in an axial direction so that gas present in a portion surrounded by the cylindrical portion and the centering portion is sometimes exhausted is provided on the outer periphery of the lower mold. An apparatus for forming an optical element according to a second aspect of the present invention includes a glass material installation section for installing a glass material, and a cylindrical section provided below the glass material installation section and provided coaxially with the glass material installation section. In a molding apparatus for an optical element having a glass transport member comprising: an upper die and a lower die coaxially arranged to face each other; and a transport arm for transporting the glass transport member between the upper die and the lower die. A centering part for centering the glass conveying member and the lower mold by fitting with the cylindrical part of the glass conveying member, and the cylindrical part and the centering when the centering part is fitted to the cylindrical part. A ring-shaped centering member having an exhaust portion that exhausts gas present in a portion surrounded by the portion and the outer portion of the lower die.

[0007]

According to the present invention, when the lower mold and the centering portion are fitted into the cylindrical portion of the glass conveying member, the gas in the cylindrical portion can be smoothly exhausted without enclosing the gas.

[0008]

1 to 8 show this embodiment, FIGS. 1 and 2 are longitudinal sectional views of a main part of a molding apparatus, FIG. 3 is a transverse sectional view of a lower mold and a centering ring, and FIGS. 6 is a cross-sectional view showing a modified example of the centering ring, FIG. 7 is a plan view showing a modified example of the centering ring, and FIG. 8 is a longitudinal sectional view showing a modified example of the centering ring.

In FIG. 1, reference numeral 1 denotes a transfer arm for holding a glass transfer member (hereinafter, referred to as a transfer member) 3 on which a glass material 2 is placed and transferring the glass material 2 between an upper mold 4 and a lower mold 5. A fitting portion 6 for holding the transport member 3 is formed at the distal end of the transport arm 1. A receiving portion 7 formed of a step portion is formed in the upper portion of the fitting portion 6 to hold the transport member 3. And the transfer arm 1
Each of the upper and lower dies 4 and 5 is configured to be movable in a direction orthogonal to the axis thereof.

The conveying member 3 is formed in a substantially ring shape, and a flange portion 8 for engaging with the receiving portion 7 is formed on an outer upper portion thereof. The outer diameter of the transfer member 3 is formed to be slightly smaller than the inner diameter of the fitting portion 6, and is formed such that a gap 9 is formed between the transfer member 3 and the fitting portion 6 when held by the transfer arm 1. On the other hand, a storage part 10 for the glass material 2 is provided on the upper inside of the transport member 3. At the lower part of the storage part 10, a mounting part 11 is formed as a glass material installation part composed of a step part for mounting the glass material 2,
The hole of the mounting portion 11 is configured to have a larger diameter than the outer diameter of the lower die 5. Further, a cylindrical portion 12 for aligning the lower die 5 with the lower die 5 is formed at a lower portion inside the transport member 3.

The upper mold 4 and the lower mold 5 are coaxially opposed to each other, and molding surfaces 4a and 5a each having a shape corresponding to a desired optical element shape are formed on opposing surfaces of the upper mold 4 and the lower mold 5, respectively. ing. The upper mold 4 and the lower mold 5 are connected to a drive device (not shown) so that they can approach and move away from each other.

The lower die 5 is provided with a ring-shaped centering ring 15 as a centering member. Centering ring 1
5 is made of a material having the same or different thermal expansion coefficient as that of the lower mold 5 so that the lower mold 5 can move in the axial direction with respect to the lower mold 5 at normal temperature and is integrated with the lower mold 5 at the temperature at the time of press molding. The outer diameter portion 16 is formed so as to fit into the inner peripheral surface of the cylindrical portion 12 of the transport member 3. Further, a tapered portion 17 is formed at the tip of the centering ring 15 to absorb the displacement of the axis of the transport member 3 and the lower mold 5 and to facilitate the fitting of the cylindrical portion 12. , Its outer diameter 1
6 has an axially concave groove 18 (FIG. 3) for exhausting air.
Reference) is formed.

In the molding apparatus having the above configuration, first, the glass material 2 is placed on the transfer member 3 and held by the fitting portion 6 of the transfer arm 1. After the transport member 3 is heated to a predetermined temperature by heating the transport member 3, the transport arm 1 is moved to dispose the transport member 3 on the axis of the upper die 4 and the lower die 5.

The lower die 5 integrated with the centering ring 15 is raised in relation to the arrangement of the conveying member 3. As the lower mold 5 rises, the tapered portion 1 of the centering ring 15
The centering ring 15 is inserted into the cylindrical portion 12 together with the lower mold 5 while the tip 7 contacts the inner peripheral lower end of the cylindrical portion 12 of the transport member 3. During this insertion, the outer diameter portion 16 of the centering ring 15 and the inner diameter portion of the cylindrical portion 12 are fitted together, and as shown in FIG.
And centering of the conveying member 3 are performed. Thereafter, the lower mold 5 is further raised and pressed into a desired shape by the molding surfaces 4a and 5a.

According to this embodiment, when the outer diameter portion of the centering ring and the cylindrical portion of the conveying member are fitted, it is possible to prevent the inside air from being wrapped, and the conveying member is obliquely fitted at the time of fitting. There is no thing to lift.

In this embodiment, the concave groove 18 is formed in the outer diameter portion 16 of the centering ring 15. However, the present invention is not limited to this, and as shown in FIGS. The same effect can be obtained even if the shape of the groove is not limited to a concave shape but a polygonal shape. Further, as shown in FIGS. 7 and 8, the groove may be formed so as to communicate with the inner peripheral surface and the lower end surface of the centering ring.

[0017]

Embodiment 2 FIG. 9 is a longitudinal sectional view of a lower die and a centering ring showing the present embodiment. In this embodiment, a centering ring 19 formed of a porous member such as carbon or alumina is used instead of the centering ring 15 in the first embodiment.
Is different from that of the first embodiment in that the other components are composed of the same components.
Description of the configuration is omitted.

The porous centering ring 19 of this embodiment has the same function as the air exhaust groove 18 of the first embodiment.

According to the present embodiment, fine processing of grooves and the like is not required, which is advantageous in manufacturing a centering ring.

[0020]

Embodiment 3 FIG. 10 is a vertical sectional view of a lower die showing this embodiment. In this embodiment, the lower mold 5 and the centering ring 15 in the first embodiment are eliminated, and the upper part of the lower mold 20 is formed in the same shape as the centering ring 15. Hereinafter, the configuration and operation are the same as those of the first embodiment, and the description of the configuration and operation will be omitted.

According to the present embodiment, it is possible to assemble with higher precision as compared with the above embodiments.

[0022]

As described above, according to the optical element molding apparatus of the present invention, the wrapping of the air generated when the centering member for positioning the transfer member with respect to the lower mold and the transfer member is fitted is prevented. This has the effect that the positioning can be performed stably and with high precision.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view showing a main part of a first embodiment.

FIG. 2 is a vertical sectional view showing a main part of the first embodiment.

FIG. 3 is a cross-sectional view of the centering ring according to the first embodiment.

FIG. 4 is a cross-sectional view showing a modification of the centering ring according to the first embodiment.

FIG. 5 is a cross-sectional view showing a modification of the centering ring according to the first embodiment.

FIG. 6 is a cross-sectional view showing a modification of the centering ring according to the first embodiment.

FIG. 7 is a plan view illustrating a modification of the centering ring according to the first embodiment.

FIG. 8 is a cross-sectional view showing a modification of the centering ring according to the first embodiment.

FIG. 9 is a longitudinal sectional view of a lower mold and a centering ring showing Embodiment 2.

FIG. 10 is a vertical sectional view of a lower die showing a third embodiment.

FIG. 11 is a partial longitudinal sectional view showing a conventional example.

[Explanation of symbols]

 Reference Signs List 1 transfer arm 2 glass material 3 transfer member 4 upper die 5 lower die 12 cylindrical part 15 centering ring 16 outer diameter part 17 taper part 18 groove

Claims (2)

(57) [Claims] A glass material installation part for installing a glass material; and a glass conveying member comprising a cylindrical part provided below the glass material installation part and provided coaxially with the glass material installation part. An upper element and a lower element coaxially opposed to each other, and a molding device for an optical element having a transport arm for transporting the glass transport member between the upper mold and the lower mold, wherein a cylindrical portion of the glass transport member; A centering portion for centering the glass transport member and the lower mold by fitting, and a portion surrounded by the cylindrical portion and the centering portion when the centering portion is fitted to the cylindrical portion. An optical element molding apparatus, comprising: an exhaust portion having a groove formed in an axial direction so as to exhaust gas to be exhausted; 2. A glass conveying member comprising: a glass material setting portion for setting a glass material; and a cylindrical portion provided below the glass material setting portion and provided coaxially with the glass material setting portion. An upper element and a lower element coaxially opposed to each other, and a molding device for an optical element having a transport arm for transporting the glass transport member between the upper mold and the lower mold, wherein a cylindrical portion of the glass transport member; A centering portion for centering the glass transport member and the lower mold by fitting, and a portion surrounded by the cylindrical portion and the centering portion when the centering portion is fitted to the cylindrical portion. And a ring-shaped centering member having the following configuration: