JPH0733452A - Forming device for optical element - Google Patents

Abstract

PURPOSE:To provide a forming device for optical elements which enables rapid heating and uniform heating and has high production efficiency by arranging plural pairs of upper molds and lower molds in series at equal intervals within the same master mold and paralleling the arranging direction thereof with a heating source. CONSTITUTION:Plural pairs of the upper mold members 1 and the lower mold members 2 are arranged in series and at equal intervals in the same master mold 4 and further in parallel with the heating source 8 disposed outside the master mold 4, by which a mold 30 for simultaneously forming the plural optical elements is constituted. This mold 30 for forming is arranged in a heating zone 20 and the upper mold members 1 are pulled up to supply glass blanks 3 onto the lower mold members 2. The upper mold members 1 are then lowered and are heated by the heating source 8 to simultaneously heat the upper mold members 1 and the lower mold members 2 by heat conduction from the master mold 4. The glass blanks 3 heated to a softened state are pressed, by which desired shapes are transferred onto the surfaces of the glass blanks 3 and the optical elements are produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises press-molding a heat-softened glass material with upper and lower mold members,
The present invention relates to an optical element molding apparatus for manufacturing a highly accurate optical element such as an aspherical lens.

[0002]

2. Description of the Related Art In recent years, as a method of processing optical elements such as glass lenses, a method of press-molding a heat-softened glass material with a molding die composed of upper and lower mold members has been noticed instead of a method of grinding and polishing. Has been done. Further, in order to improve production efficiency, this method has been developed into a method of equipping a plurality of pairs of upper and lower mold members in the same barrel mold and simultaneously molding them in a press zone. Among these, Japanese Patent Publication No. 271
There has already been proposed an optical element molding apparatus for performing press molding using a molding die in which a plurality of pairs of upper and lower die members are arranged on the same circumference in a barrel die as seen in Japanese Patent Laid-Open No. 75-75.

[0003]

In this method, the mold after molding is rapidly cooled to 250 ° C., taken out of the closed container, and the molded product is taken out and the glass material is put in in separate steps. . With the structure of the molding die and its arrangement, it is very difficult to automatically take out the molded product and put the glass material in the closed container. In other words, in the above arrangement, in order to ensure the centering of each pair of upper and lower die members in the barrel die and to construct the column with the strength to withstand the press pressure used, the automatic supply corresponding to each pair of the upper and lower die members is performed. It is impossible to provide each of the openings in the barrel shape.

As described above, in the case where the molded product cannot be taken out and the glass material can be charged in the closed container, there are the following problems. In other words, the number of molding dies required in continuous operation is increased because the molding dies are cooled and taken out of the closed container for each molding shot, and the molding cycle is prolonged, and the molding dies are rapidly cooled. Equipment for doing so is required.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to supply a glass material and to obtain a molded product even in a mold structure in which a plurality of glass materials are simultaneously molded. Easy to take out automatically,
An object of the present invention is to provide a molding device for an optical element that can effectively and rapidly heat a plurality of pairs of upper and lower mold members for that purpose.

[0006]

In order to solve the above-mentioned problems and to achieve the object, the present invention is to press a glass material which is in a softened state by being heated and press the surface of the glass material. A plurality of pairs of upper mold members and lower mold members for transferring a desired shape to the above, and a cylinder mold for guiding the plurality of pairs of upper mold members and lower mold members, and heat conduction from the cylinder molds. Thus, in the optical element molding apparatus configured to simultaneously heat the upper mold member and the lower mold member, a plurality of pairs of the upper mold member and the lower mold member are arranged in series and at equal intervals in the same barrel mold. And the arrangement direction is parallel to the heating source.

[0007]

Therefore, even in a mold structure having a plurality of pairs of upper and lower mold members, an opening for automatic supply of glass material and taking out of molded products which can be commonly used is provided, so that the automatic supply and removal of the molded product can be performed in a closed container. In addition, since the molds are arranged parallel to the heating source at equal intervals, the mold can be rapidly heated and uniformly heated.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows the structure of a molding die 30 placed in a heating zone (described later) for simultaneously molding ten optical elements. In the figure, reference numerals 1 and 2 denote an upper mold member and a lower mold member, respectively.
Is a barrel type for guiding the upper and lower die members. Reference numerals 5 and 6 are spacers for adjusting the thickness of the molded product, 7 is a support base, 8 is a heating source, and 9 is an opening provided in the barrel die 4. This opening 9 is provided with a vacuum suction hand, which will be described later, in the body 4
It has a space that can be inserted inside.

Reference numeral 3 is a glass material, and reference numeral 10 is
It is a pillar for withstanding the press pressure in the barrel shape. The upper mold member 1 and the lower mold member 2 are arranged in two rows with respect to the body mold 4 and are arranged in series at equal intervals, and are arranged in parallel to a heating source 8 provided outside the body mold. ing.

FIG. 2 schematically shows a part of an optical lens production apparatus using the molding die 30 as viewed from above. This apparatus is a type that performs molding of an optical element in a closed space adjusted to an atmosphere such as nitrogen gas, while moving a molding die in the order of work steps. In the figure, reference numeral 20 is a heating zone, and 21 is a vacuum suction hand for supplying a glass material. The vacuum suction hand 21 is provided with vacuum suction holes for sucking the glass material in the same arrangement as a plurality of pairs of upper and lower mold members arranged in the barrel mold, and as shown by an arrow 41, moves forward and backward. A driving source (not shown) capable of operation is provided outside the closed container. Also,
A glass material holder (not shown) is provided below the retracted position of the vacuum suction hand, and is prepared for sequentially introducing the glass material from outside the closed container into the same container by the function of the suction hand. Has been done.

The molding die 30 is heated in the heating zone 2 by a flow shown by an arrow 40 by an appropriate supply means (not shown).
0, and is positioned by a positioning device (not shown). At this time, a unit having a function as described in the specification of Japanese Patent Application No. 04-175069 (see Japanese Patent Application Laid-Open No. 5-17069) is used to collectively place 10 upper mold members of the molding die 30 in the upper part of the heating zone. It can be connected to the press shaft.

From this state, a series of subsequent steps will be described. The upper die member of the molding die placed in the heating zone is pulled up as the press shaft rises. Next, the vacuum suction hand 21 that sucks and holds ten glass materials moves forward,
The barrel die is inserted into the barrel die through the opening, and the barrel jig and the suction hand are positioned by a positioning jig (not shown). Then, after the glass material is supplied onto the lower mold member, the vacuum suction hand retracts to its original position to prepare for the next glass material supply. In other words, 10 in a closed container
Automatic supply of individual glass materials can be done easily with one operation.
Next, the glass material is heated to a desired temperature and pressed.

Here, the body type column 10 is set so as to secure a horizontal cross-sectional area which has a strength capable of withstanding the pressing pressure. In this embodiment, a pair of upper and lower die members It is about 1,500 N, and it takes about 15,000 N in total, but the design value is suppressed so that it will stop within 10 seconds due to the inclination of the axis of the upper and lower mold members. Also, FIG.
The width W of the barrel type is the minimum width (width of the opening) that the vacuum suction hand can freely carry in and carry out from the opening.
And the minimum width (cross-sectional area of the column) that can withstand the above press strength are set so as to reduce the heat capacity of the barrel die as much as possible. Further, by arranging the upper and lower mold members in parallel to the heating source, each pair of upper and lower mold members can be heated rapidly and uniformly.

In this embodiment, the required heating time is about 1
I was able to make it 30 minutes. Upon completion of press molding of the glass material, the molding die is conveyed to a cooling zone (not shown) in the next step and cooled to a desired temperature.
Then, the molded product is taken out from the molding die by the molded product take-out device which has the same specifications as the vacuum suction hand for supplying the glass material and the peripheral device. In addition,
The empty mold is returned to the heating zone again and the above steps are repeated.

In this embodiment, a progressive type device using a conveyor line or the like is shown, but a rotary type device using a turntable or the like may be used as the conveying system. Further, even if the vacuum suction hand for supplying the glass material is also used for taking out the molded product, there is no problem at all.

[0016]

As described above, according to the optical element molding apparatus of the present invention, a plurality of pairs of upper mold member and lower mold member are arranged in series and at equal intervals with respect to the barrel mold, and By arranging these so that they are parallel to the heating source,
The body mold, while having a structure that can withstand the press pressure, can have a structure having an opening for supplying a glass material and taking out a molded product, and is not limited to only in a closed container,
Wherever it is required, it can be automated, the number of molding dies required can be reduced, the molding cycle can be shortened, and it is not necessary to take out the molding dies from the closed container every shot. Further, cooling equipment for taking out the molding die is not necessary. Further, the heating time of the molding die is shortened, and the molding apparatus can have high production efficiency.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional plane view and a vertical sectional front view showing an embodiment of the present invention.

FIG. 2 is a schematic plan view for explaining an embodiment of the present invention.

[Explanation of symbols]

 1 Upper Mold Member 2 Lower Mold Member 3 Glass Material 4 Body 5, 6 Spacer 7 Supporting Base 8 Heating Source 9 Opening 10 Strut 30 Mold for Molding

Claims (1)

[Claims] 1. A plurality of pairs of upper mold member and lower mold member for pressing a glass material which is in a softened state by being heated to transfer a desired shape onto the surface of the glass material, and An optical element comprising: a barrel die for guiding a plurality of pairs of upper die members and lower die members; and heat conduction from the barrel die to simultaneously heat the upper die member and the lower die member. In the molding apparatus, a plurality of pairs of the upper mold member and the lower mold member are arranged in series and at equal intervals in the same barrel mold, and the arrangement direction is parallel to the heating source. Optical element molding device.