JPH0442821A - Forming device of glass optical element - Google Patents

Abstract

PURPOSE:To enable to produce various kinds of glass optical elements in small amount and make it possible to form highprecision lens at a low cost, by arranging plural forming chambers and providing a heating furnace between the forming chambers and a carrying member passing through the each forming chamber and heating furnace. CONSTITUTION:A carrier 7 on which a preform 6 is put in a heating furnace 4 is heated and then conveyed to a forming chamber 2 by a conveyer 5 and the preform 6 in the forming chamber 2 is subjected to press forming. The conveyer 5 is advanced by 1 pitch and the carrier 7 in the forming chamber is conveyed out of the forming chamber 2 and the next carrier 7 is conveyed into the forming chamber 2. Meanwhile, detachment of mold and attachment of mold prepared for the next process are carried out in a forming chamber 3, and then the mold is heated up to a prescribed temperature. In the forming chamber 2, at the point of time when the temperature of mold is lowered to a non-oxidizing temperature, detachment of the mold is carried out. Meanwhile, the carrier 7, on which the preform 6 formed in a forming chamber 3 for the next process is put, is put on the conveyer 5, and simultaneously, temperature in the heating furnace 4 is changed to the prescribed temperature. Then reverse pitch feed motion is started in the conveyer 5 and forming process in the forming chamber 3 is started.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a molding apparatus for glass optical elements, and more particularly to a molding apparatus suitable for producing a wide variety of products in small quantities.

[Conventional technology]

In recent years, the molding technology for optical glass lenses has become popular for cameras.

It is becoming important as an effective processing method, especially for aspherical lenses mounted on Hinokuanop.

However, conventional molding apparatuses are generally designed for mass production, and require a long time, especially when changing molds, when moving to molding different types of lenses. Therefore, when a molding device is used for producing a wide variety of products in small quantities, there is a drawback that the operating rate is significantly reduced.

Therefore, the following inventions have been disclosed to solve the above-mentioned drawbacks.

For example, in the invention described in Japanese Patent Application Laid-Open No. 63-260830, mounts to which a plurality of dies are removably attached at the same time are arranged facing each other for upper and lower dies so that they can be approached and separated in the press direction, and each of the mounts is The mold, which is rotatably held and preheated according to the desired lens, is indexed by the rotation of the mount, and the molding process proceeds to molding a different type of lens.

According to the above-mentioned apparatus, there is no need for mold exchange and accompanying mold heat-down and heat-up, and the setup time when moving to molding a different type of lens can be significantly shortened.

[Problem to be solved by the invention]

However, the invention described in JP-A-63-260830 has the following problems.

In other words, in this type of molding equipment, the eccentricity accuracy of the upper and lower molds is extremely important, and a mutual shift amount of several microns and a tilt amount of several minutes are required. Because of the indexing structure, the precision of the mount parts is extremely strict, and the assembly precision of the parts and rotational precision of the mount must also be strictly controlled, making it cost effective.

In addition, as sales and manufacturing have become more and more directly linked, and manufacturing has become required to quickly respond to orders from sales, production organization has shifted from daily units to half-day units to hourly units. This has been shortened to ``and a dizzying number of orders have been issued to change the production organization.'' Since the molding apparatus sets a plurality of molds on the mount at once and starts molding, it is impossible to replace the molds after molding has started, and the production organization span that can be handled is limited to one day.

Therefore, the present invention was developed focusing on the above-mentioned problems, and it is possible to mold glass lenses from a wide variety of products in small quantities to a wide variety of products in extremely small quantities while responding to production organization instructions for extremely short spans, and with high precision. The object of the present invention is to provide a molding apparatus for a glass optical element that can mold a lens at a low cost.

[Means and effects for solving the problems] The present invention provides a glass optical element molding apparatus that presses an optical element material between a pair of removable molds provided in a molding chamber to mold an optical element. arranging a plurality of molding chambers,
A heating furnace is installed between the molding chambers, and
A conveyor member is provided that passes through each molding chamber and the heating furnace.

FIG. 1 is a conceptual diagram of a glass optical element molding apparatus according to the present invention.

This molding apparatus 1 is provided with a molding chamber 2 and a molding chamber 3 having the same structure and each having a mold removably attached to a mount provided inside the molding apparatus. A heating furnace 4 is provided between the molding chamber 2 and the molding chamber 3, and the molding chamber 2. A conveyor 5 passing through the molding chamber 3 and the heating furnace 4 is provided.

A carrier 7 on which a preform 6 is placed on the conveyor 5
are placed at regular intervals.

The molding apparatus 1 having the above configuration first heats the carrier 7 on which the preform 6 is placed in the heating furnace 4 . After heating,
The carrier 7 is conveyed to the molding chamber 2 by the conhair 5, and the preform 6 is press-molded within the molding chamber 2. After the press is finished, the conveyor 5 partially advances one bit (to the left in the figure), the carrier 7 in the molding chamber 2 is conveyed to the outside of the molding chamber 2, and the next carrier 7 is conveyed into the molding chamber 2.

During this time, in the molding chamber 3 where the previous step of molding has been completed, the mold is removed and the mold is attached in preparation for the next step of molding, and then the mold is heated up to a predetermined temperature. When the molding process in the molding chamber 2 is completed, the mold in the molding chamber 2 starts to heat down, and the mold is removed when the temperature of the mold drops to a non-oxidizing temperature.

During this time, the preform 6 to be molded in the molding chamber 3 for the next process
The carrier 7 on which the is placed is placed on the conveyor 5, and the temperature of the heating furnace 4 is changed to a predetermined temperature. and,
The conhair 5 starts a reverse pitch feeding operation (rightward in the figure), and the molding process in the molding chamber 3 begins.

(Example) Hereinafter, an example of the molding apparatus for a glass optical element according to the present invention will be described in detail with reference to an open view.

2 and 3 show an embodiment, in which FIG. 2 is a partially sectional front view of the molding apparatus, and FIG. 3 is a partially enlarged sectional view.

1 is a molding device, and this molding device 1 has a molding chamber 2 with the same configuration.
and a molding chamber 3 are provided. A heating chamber 4 is provided between the molding chambers 2 and 3, and the molding chambers 2. A conveyor 5 passing through the molding chamber 3 and the heating furnace 4 is provided.

In each molding chamber 2.3, an annealing furnace 8 and an annealing furnace 9 having the same configuration are installed adjacent to each other on the side opposite to the heating furnace 4.

Opening/closing shutters 10 and 11 are provided at both side openings in the molding chamber 2 that are in contact with the heating furnace 4 and annealing furnace 8, and similarly, opening/closing shutters 1 are provided at both side openings of the molding chamber 3.
2.13 is provided.

Each opening/closing shutter 10, 11, 12.13 is connected to the molding chamber 2,
The cylinder shaft 1 is attached to the cylinder 14 fixed to the upper side of the cylinder 3.
5, and is configured to be openable and closable in the vertical direction.

An upper mold mount 17 is fixedly installed on the lower surface of the upper space 16 in the molding chamber 2, and an upper mold heater 1 is installed on the upper side of the upper mold mount 17.
8 is installed. The upper mold 19 is removably attached to the upper mold mount 17 by a ring 20, and is configured so that the heat of the upper mold heater 18 is transmitted via the upper mold mount 17. At the center of the lower base 21 of the molding chamber 2 is a press shaft 2 that is connected to a drive source (not shown) and is movable up and down.
2 is fitted, and the lower die mount 23 is attached to the upper end of the press shaft 22.
is permanently installed. Like the upper mold 19, the lower mold 24 is removably attached to the lower mold mount 23 by a ring 25, is heated by a lower mold heater 26, and is configured to be movable up and down within the molding chamber 2. .

The front cover 27 of the molding chamber 3 has two openings, upper and lower.
Each opening has an upper glass door 28° and a lower glass door 29.
is provided so that it can be opened and closed. This upper and lower glass door 28.
29 is configured so that when it is closed, the situation inside the molding chamber 3 can be visually checked, and when it is opened, it is possible to change the mold inside the molding chamber 3.

The inside of the heating furnace 4 is separated into a left heating furnace 32 and a right heating furnace 33 by a shutter 30 that can be opened and closed and a partition 31. Outer wall 34 of heating furnace 4. Shutter 30 and partition 31
All have a heat insulating function, and the left and right heating furnaces 32 and 33 are configured to be able to function independently without being substantially affected by each other's furnace temperatures.

The conveyor 5 passing through each molding chamber 2, 3, heating furnace 4, and each annealing furnace 8.9 is configured to be able to be conveyed in both left and right directions at a predetermined pitch by a drive device (not shown), and a carrier is placed thereon. Mounting holes 5a are bored at regular intervals.

The molding apparatus 1 having the above-mentioned configuration is configured to move the upper mold 19 and the lower mold 24 in the molding chamber 2 to the upper and lower mold heaters 1 before entering the molding process.
B, heated to a predetermined temperature by 26. The right heating furnace 33 is set as a preheating furnace at a temperature slightly lower than the transition point of the glass to be formed. The left heating furnace 32 is set at a temperature higher than the softening point of the glass to be formed as the main heating furnace. The annealing furnace 8 is set at a temperature slightly higher than the strain removal point of the glass, which is set to remove strain from the molded lens. The preform 6 is placed inside a carrier 7 in which a hole 7a through which the tip of the lower die 24 can pass is formed. This carrier 7 is placed in the conveyor 50 placement hole 5a.

On the other hand, the upper and lower heaters and annealing furnace 9 in the molding chamber 3 are in an OFF state, and the shutters 12 and 13 on both sides of the molding chamber 3 are in an OFF state.
It is also raised and open.

The molding process begins with the shutter 10. The shutter 11 and the shutter 30 are opened at the same time, the conveyor 5 is sent to the left by one pitch, and the carrier 7 placed on the conveyor 5 and in the right heating furnace 33 is transferred into the left heating furnace 32. The carrier 7 that was in the position is transported 0 times into the molding chamber 2. and,
Each shutter 10°11.30 closes simultaneously. At this time,
The preform 6 placed on the carrier 7 that has been transported into the molding chamber 2 and the left heating furnace 32 is heated to a predetermined temperature.

The lower mold 24 is raised by the press shaft 22 relative to the carrier 7 transported to the molding chamber 2, lifts the preform 6, and molds it between it and the upper mold I9. After molding, lower mold 2
4 descends and places the molded lens on the carrier 7 again. Open each shutter 10.11.30 and conveyor 5
The carrier 7 in the molding chamber 2 is conveyed to the left by one pinch, and the carrier 7 in the molding chamber 2 is transported into the annealing furnace 8.
The next carrier 7 is conveyed from there. By repeating the above steps, a required number of lenses are molded within the molding chamber 2.

While molding is being carried out in the molding chamber 2, in the molding chamber 3, the mold that has already been molded is replaced, and the mold to be molded next begins to be heated up.

When the molding in the molding chamber 2 is completed, the upper and lower heaters 1B, 26 and the annealing furnace 8 in the molding chamber 2 are turned off, and the annealing furnace 9 is turned on. Furthermore, the temperatures are changed to their respective predetermined temperatures so that the left heating furnace 32 functions as a preliminary heating furnace and the right heating furnace 33 functions as a main heating furnace. A preform 6 to be molded in the molding chamber 3 in the next molding process is placed on the carrier 7 supplied onto the conveyor 5. Thereafter, the conveyor 5 starts to be fed in the right direction, which is opposite to when molding was performed in the molding room 2, and the next molding process is started.

According to this embodiment, the productivity is significantly improved because the setup work of mold exchange can be done externally.

〔Effect of the invention〕

As explained above, the glass optical element molding apparatus according to the present invention has a plurality of molding chambers each having a mount and a pressurizing system, so that the time required for mold exchange is entirely spent in an external stage. This can contribute to a significant improvement in operating rates. In addition, emergency production instructions can be responded to immediately by simply selecting the mold to be replaced and inputting the molding conditions. Furthermore, it is not necessary to use a complicated drive mechanism to achieve the precision of the upper and lower molds, and since the conveyance system and heating furnace are shared, this also leads to a reduction in molding machine costs.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram of a molding apparatus for glass optical elements according to the present invention, FIGS. 2 and 3 show the same embodiment, FIG. 2 is a front view of the molding apparatus with a part cut away, and FIG. is a partially enlarged sectional view. 1... Molding device 2.3... Molding chamber 4... Heating chamber 5... Conveyor 6... Preform 7... Carrier 8.9... Annealing furnace 10.11, 12, 13.30...Shutter 14...
・Cylinder 15...Cylinder shaft 16...Upper base 17...Upper die mount 18...Upper die heater 19...Upper die 2025...Ring 21...Lower base 22...Press Shaft 23...Lower die mount 24...Lower die 26...Lower die heater 27...Front cover 28...Upper glass door 29...Lower glass door 31...Partition 32... Left heating furnace 33... Right heating furnace Figure 1 Molding 2 Place 3 Molding chamber heating chamber Conhair preform carrier

Claims (1)

[Claims] (1) In a glass optical element molding apparatus that presses an optical element material between a pair of removable molds provided in a molding chamber to mold an optical element, a plurality of molding chambers are provided, and A molding apparatus for a glass optical element, characterized in that a heating furnace is provided between the disposed molding chambers, and a conveying member passing through each molding chamber and the heating furnace is provided.