JPH06293528A - In-mold heating and cooling device for glass lens forming device - Google Patents

Abstract

PURPOSE:To improve surface precision by press molding the glass cob heated and softened by the forming molds which are provided with heating means and cooling means outside the forming molds and heat and cool the inside of the molds via the heat conducting members. CONSTITUTION:The upper mold 5 and the lower mold 6 are uniformly heated to a prescribed temp. by means of circular cylinder-shaped heat conducting members 13, 14 which are made of BN, etc., and are inserted and mounted at one end into the heating and cooling members 22, 23 having a doughnut shape and constituted of heating parts, such as electromagnetic heating, and cooling parts and are inserted at the other end into blind holes at the centers of the non-forming surfaces of the upper mold 5 and the lower mold 6. The in-mold temps. are measured and controlled by thermocouples 8, 9 which are embedded in parallel near these heat conducting members 13, 14. The glass cob softened by heating is then held between the forming surfaces of the upper mold 5 and the lower mold 6 and is press molded. The forming molds are uniformly cooled via the heat conducting members 13, 14 from the heating and cooling means 22, 23 after the end of the molding, by which the glass lens 12 having the improved surface precision is obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-mold heating / cooling device for heating and cooling a glass in a device for press-molding a glass lens with a pair of molding dies after heating and softening the glass.

[0002]

2. Description of the Related Art As conventional techniques for heating and cooling the above-mentioned forming die, there are JP-A-4-46024 and JP-A-4-154631. The technique disclosed in the former publication will be described with reference to FIG. FIG. 6 shows a fourth example described in the former (Japanese Patent Laid-Open No. 4-46024).
It is sectional drawing from the front which shows the shaping | molding die of the glass optical component shown in the figure. As shown in the figure, heater units 10 and 11 are embedded in the upper mold 5 and the lower mold 6, and the heating of the units heats the upper mold 5 and the lower mold 6 in the mold to measure the temperature with thermocouples 8 and 9. The heating temperature is controlled.

The technique disclosed in the latter publication will be described with reference to FIG. FIG. 7 shows the latter (JP-A-4-
FIG. 1 is a cross-sectional view from the front of a glass molding apparatus used in the method for manufacturing the optical element shown in FIG. In the mold cooling after being heated by the heater 7 set on the outer periphery of the upper mold, the cooling passages 3, 3 are respectively provided inside the upper shaft 1 and the lower shaft 2 and inside the upper mold 5 and the lower mold 6.
4 is provided, and the cooling of the upper mold 5 and the lower mold 6 is performed by passing the refrigerant through this channel, and the temperature is measured by the thermocouples 8 and 9 to control the cooling temperature.

[0004]

Generally, in order to obtain good surface accuracy of the two light flux effective surfaces of the molded lens, it is necessary to make the average temperature of the entire molded product, and in the case of a convex lens, Heat build-up in the center of the lens for cooling inside the mold (outer peripheral heating), and in the case of a concave lens, heat build-up in the lens outer peripheral edge for heating inside the mold (cooling outside) forming the shape of the lens It is desired for heat retention. However, in the technique described in the former publication, that is, in the heating device, the heater units 10 and 11 have to be provided in the upper mold 5 and the lower mold 6 in the above-described conventional technique. It will be buried. Therefore, the required large heater cannot be used (arranged), and there is a problem that the heating capacity is limited.

In the cooling device of the technique described in the latter publication mentioned above, since the refrigerant flow paths 3 and 4 must be provided in the upper mold 5 and the lower mold 6, a large flow path is formed in terms of space. It is difficult to obtain a large flow rate. Therefore, there is a problem that the cooling capacity must be small. Therefore, in the conventional heating and cooling devices according to the above publications, the ability to perform heating and cooling within the mold is insufficient, and it is difficult to make the temperature of the entire molded product uniform, and It was difficult to mold the surface precision of both sides with high quality and high productivity.

The present invention has been made in view of the above problems, and is configured so as to eliminate the size limitation of a device for heating and cooling in a molding die and to sufficiently satisfy the capability of the die. It is an object of the present invention to provide a heating / cooling device for the inside of a glass lens molding die that facilitates temperature control of heating and cooling of the inside, improves the surface accuracy of the formed lens, and has good productivity.

[0007]

The concept of the present invention will be described with reference to the drawings. FIG. 1 is a front sectional view showing the concept of an in-mold heating / cooling device of a glass lens molding device of the present invention. Reference numeral 12 shown in the drawing is a glass lens that is press-molded by placing and sandwiching a glass gob that has been heated and softened in the previous step between the molding surfaces of the upper die 5 and the lower die 6. A hole having a bottom is formed at the center of the upper end surface of the disk-shaped upper die 5, and one end of a columnar heat conducting member 13 is inserted and mounted in the hole. Further, the other end of the heat conducting member 13 is inserted and mounted in a hole of a doughnut-shaped heating / cooling member 22, and the temperature of the upper die 5 is adjusted by the heat conducting member 13.
It is configured to conduct to.

At the lower position facing the molding surface of the above-mentioned upper mold 5, a lower mold 6 having a molding surface arranged above is constructed so as to be vertically movable, and like the upper mold 5, it has a disc shape. A bottomed hole is formed at the center position of the lower surface, and one end of the columnar heat conducting member 14 is inserted and mounted in the hole. Further, a donut-shaped heating / cooling member 23 is inserted and attached to the other end of the heat conducting member 14, and is configured to conduct heating or cooling temperature into the lower mold 6 through the heat conducting member 14. There is. Further, thermocouples 8 and 9 are embedded in parallel in the respective axial directions of the upper die 5 and the lower die 6, that is, in the vicinity of the heat conducting members 13 and 14, and the temperature inside the die is measured. .

[0009]

The operation of the concept of the present invention having the above configuration will be described. The heat that is heated or cooled by the heating / cooling units 22 and 23 is transmitted from one end of the heat conduction members 13 and 14 to the other end, and further, the upper mold 5 and the lower mold 6 that are continuously mounted to the other ends. By being supplied to the center, the upper mold 5 and the lower mold 6 are heated from the center at a desired uniform temperature. The upper mold 5 and the lower mold 6 are
The temperature is constantly measured by the thermocouples 8 and 9, and the output is adjusted based on the value to control the temperature. According to the present invention having the above-mentioned configuration and action, since the heating / cooling unit is provided outside the mold, there is no need to limit the size of the device of the heating / cooling unit. can do. Therefore, a wide range of temperature control is possible, and the temperature of the molded product can be easily equalized, so that a highly accurate glass lens with excellent quality can be manufactured with high productivity.

[0010]

Embodiment 1 A specific example of the in-mold heating and cooling device for a glass lens molding die of the present invention will be described with reference to the drawings. FIG. 2 is a cross-sectional view from a front view showing a main part of the heating and cooling device in the mold of the glass lens molding apparatus of the present invention according to the first embodiment.
FIG. 3 is a sectional view from the front showing a modification of the cooling unit of the first embodiment. In the drawings, the same members, shapes and configurations as those in FIG. 1 used for the above-described concept of the present invention are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 2, a glass gob that has been heated and softened to a predetermined temperature in the previous step is sandwiched between the molding surfaces of a disk-shaped upper die 5 and a lower die 6 and pressed by the upward movement of the lower die 6. A molded glass lens 12 is provided. A bottomed hole is bored at a desired depth at the center position on the non-molding surface side of the pair of molding dies 5 and 6, and the columnar heat conduction member 13 is formed in the hole to have a dimension corresponding to the hole diameter. , 14 are inserted and mounted at their respective ends. The heat conducting members 13 and 14
The cooling parts 17 and 18 are wound around the outer peripheral surface of the other end of the. Further, the heat conducting member 13 between the upper mold 5 and the cooling unit 17 and the heat conducting member 14 between the lower mold 6 and the cooling unit 18 have heating portions 15, 16 are provided.

Further, the heat transfer members 13 and 1 on the non-molding surface side of the upper mold 5 and the lower mold 6, that is, on the upper surface side of the upper mold 5 and the lower surface side of the lower mold 6.
Thermocouples 8 and 9 for measuring the temperatures of the upper die 5 and the lower die 6 are embedded in parallel in the vicinity of each of the four. Further, in the vicinity of the outer peripheral surface of each of the molding dies 5 and 6, an upper mold 5 and a lower mold 6 are formed.
Further, peripheral heating portions 19 and 20 are provided to supplement the heat of the glass gob to be molded. An outer peripheral cooling blow 21 for cooling the upper mold 5, the lower mold 6 and the glass lens 12 is provided at an intermediate position between the outer peripheral heating portions 19 and 20 of the upper mold 5 and the lower mold 6, that is, in the vicinity of the outer peripheral surface of the glass gob. Is provided.

Next, the operation of this embodiment having the above structure will be described. First, in the molding of a molded product such as a convex lens in which a heat pool is generated in the central portion, the heat of the heating portions 15 and 16 is transferred to the central portions of the upper mold 5 and the lower mold 6 via the heat conducting members 13 and 14, respectively. The heat of the outer peripheral heating portions 19 and 20 arranged on the outer peripheral surfaces of the upper mold 5 and the lower mold 6 is supplied to the outer peripheral surfaces of the upper mold 5 and the lower mold 6 while being supplied. That is, the molding is performed by supplying the heat from both the inner and outer surfaces, or by supplying only one of the heat amounts. In this case, the transition temperature T of the glass material is previously set.
The entire mold is uniformly heated to a temperature of g or less, and the glass gob that has been heated and softened to the transition point temperature in the previous step is transferred and placed between the upper mold 5 and the lower mold 6 by a transfer means (not shown). The lower die 6 is moved upward to be sandwiched with the upper die 5 and press-formed by pressing.

After completion of the above molding, in order to accelerate the cooling of the central portion of the molded product (glass lens 12), the outer peripheral heating portions 19 and 20 supplement the heat of the upper mold 5, the lower mold 6 and the outer periphery of the glass lens 12. By lowering the temperatures of the heat conducting members 13 and 14 by the cooling units 17 and 18 in which the outputs of the heating units 15 and 16 are lowered, the temperatures of the central portions of the upper mold 5 and the lower mold 6 can be relatively lowered. That is, the central portion of the glass lens 12 where heat accumulation may occur is cooled to uniformly cool the glass lens 12. This makes it possible to obtain a glass lens of which the light flux effective surfaces on both sides are highly accurate and of good quality. In the above case, since the cooling part for cooling the central part of the upper mold 5 and the lower mold 6 is performed via the heat conduction members 13 and 14 provided outside the molding dies 5 and 6, a high-performance cooling part is provided. Therefore, the cooling speed and output can be selected according to the shape of the glass lens 12.

Further, when molding a molded product such as a concave lens in which heat buildup occurs at the outer peripheral edge, the heating parts 15, 1 are preliminarily formed.
After uniformly heating the heat of 6 through the heat-conducting members 13 and 14 to the upper mold 5 and the lower mold 6, respectively, to the transition temperature Tg of the molding material or less, the glass gob that has been heat-softened in the previous step in advance is used. It is conveyed and clamped between the upper mold 5 and the lower mold 6. in this case,
In order to make the heating temperatures of the molds 5 and 6 uniform, the upper mold 5,
The cooling of the outer peripheral portion of the lower mold 6 is promoted. That is, the outer peripheral cooling blow 21 is actuated to operate the molding dies 5, 6 and the glass gob 12.
Then, N ₂ cooling glass is sprayed to cool the outer peripheries of the molds 5 and 6 and the glass gob, and the central portions of the molding molds 5 and 6 are supplemented. In order to perform this supplementary heat, the outputs of the heating units 15 and 16 are increased to raise the temperatures of the heat conducting members 13 and 14, thereby relatively raising the temperatures of the central portions of the molding dies 5 and 6. By performing the above action, the temperature of the upper mold 5 and the lower mold 6 and the temperature of the glass gob can be made uniform.
Subsequently, the outer circumference of the glass lens 12 having a heat pool is cooled by the outer circumference cooling blow 21 to uniformly cool the glass lens 12, so that the glass lens 12 having good surface accuracy on both sides is molded with good quality.

In the above, since the heating portions 15 and 16 for heating the central portions of the upper die 5 and the lower die 6 can be provided outside the die via the heat conducting members 13 and 14, respectively, high performance is achieved. A heating section could be provided. That is, the heating speed and the increase / decrease in output can be freely selected according to the shape of the glass lens to be molded. In addition, the cooling unit 17,
Since 18 is arranged around the heat conducting members 13 and 14, it is possible to switch between heating in the upper mold 5 and lower mold 6 and cooling in the mold with the same molding machine. The glass lens can be molded by the same molding machine, and the surface precision of both surfaces can be molded with good advantages.

The heat conducting member 1 in this embodiment described above.
For the materials 3 and 14, it is preferable to use a high thermal conductive material in order to improve the temperature control response, but in the present embodiment, BN, SC, aluminum nitride magnesia, sialon, etc. are used. Further, as the heating means of the heating units 15 and 16, a general resistance wire coil heater or a ceramic heater may be used, but a high capacity high frequency coil or a high response electromagnetic heating may be used. Furthermore,
As a cooling means of the cooling parts 17 and 18, there is generally a method of passing a refrigerant through a pipe, but as shown in FIG. 3, a large number of grooves are formed on the outer peripheral surface of the heat conducting member 14 and the inside of the grooves is formed. It is also possible to insert a fixing pin 29 into the above and cool with air from an air nozzle 25 arranged near the outer circumference of a cylindrical cooling fin 24 integrally mounted with the heat conducting member 14.

[0018]

Second Embodiment A second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a cross-sectional view from the front showing the main part of only the lower mold according to the second embodiment of the heating and cooling device in the mold of the glass lens molding apparatus of the present invention. FIG. 5 is a sectional view taken along the line AA shown in FIG. In the drawings, the same members, shapes and configurations as those of FIG. 1 used for the above-described concept of the present invention and FIGS. 2 and 3 used for the above-described first embodiment are designated by the same reference numerals, and their description will be omitted. Omit it.

The difference between the above-described first embodiment and this embodiment is that the structure and action of the heat conducting member are greatly different as shown in the figure. That is, in the first embodiment, the heat conducting members 13, 1
While a cylindrical body formed of BN, SC, aluminide nitride magnesia, sialon, etc. was used as the material of No. 4, in the present embodiment, in order to further improve the thermal conductivity and speed up. , One end surface is a bottomed cylindrical shape, the opening is arranged downward, and the other end surface of the opening end surface is sealed by caulking caps 33, 34. (Not shown), 3
2 is an upper mold 5 (not shown), and one bottomed end is inserted and mounted in a hole formed in the center of the non-molding surface of the lower mold 6. In addition, in the cylindrical cavity of the heat conducting member 30, the wick net 3 that covers the entire inner peripheral wall surface is formed.
The mesh material forming 5 (not shown) and 36 is made of nickel alloy-based, stainless steel-based, inconel-based, tungsten alloy-based material, or alumina-based, zirconia-based, or glass-based fiber. Mesh material may be used. The heat conducting members 31, 32 and the caulking caps 33, 3 described above.
The material used for 4 is nickel alloy type, stainless steel type,
Inconel, using Tansuten alloy system is covered up that the outer peripheral surface T _T -C, at such T _T -N.

Instead of the wick net materials 35 and 36 arranged in the cavities of the heat conducting members 31 and 32, a large number of wick nets 35 and 36 are provided in the cavities in the axial direction along the wall peripheral surface in the longitudinal direction as shown in FIG. The groove 38 is formed, and the inside thereof is vacuumed (10 ⁻³ to 10 ⁻⁶ T
orr), and then the mineral vaporization material is placed in the cavity for 3 to 5 times.
Enclosed by volume% and sealed with caulking caps 33 and 34,
Use a heat pipe structure. The mineral vaporization material enclosed in this varies depending on the operating temperature range,
Water at 500 ° C Downtherm at 250-600 ° C, 300
Mercury at ~ 800 ° C, potassium at 500 ~ 1000 ° C, 60
Most preferred is sodium at 0 to 1350 ° C.

The operation of the above configuration will be described. Upper mold 5,
When the lower mold 6 is heated, when heated by the heating units 15 and 16, the mineral vaporization material is vaporized inside the heat conducting members 31 and 32 in the vicinity thereof and the arrow 42 is drawn to the heat radiation point 40.
It diffuses and liquefies as shown in. Liquefied mineral vaporization material,
The inner wall surfaces of the heat conducting members 31 and 32 flow in the wick net material 36 or in the vertical grooves 38 by a capillary phenomenon so that the heating unit 1
Return to the vicinity of 5,16. On the contrary, when cooling the upper mold 5 and the lower mold 6, the heat conducting member 3 near the cooling units 17 and 18 is used.
The inside of 1, 32 becomes the heat dissipation points 39, 40 and diffuses 4
The inner surfaces of the heat conducting members 31 and 32, which come into contact with the insides of the upper mold 5 and the lower mold 6, serve as points for liquefying the mineral vaporized materials 1 and 42 to serve as vaporization points 39 and 40, thereby operating the heat exchange action.

Since the above phenomenon occurs continuously, high-speed and highly efficient heat conduction becomes possible. As a result, the usual solid material (metal ceramics) is 10 to 150 W / m.
Whereas the traditional heat transfer coefficient of ⁰ K, this heat exchange heat pipe structure provides a thermal conductivity of 10 ³ to 2 × 10 ⁴ W / m ⁰ K.

According to the present embodiment described above, the heat conducting member 3
Since the thermal conductivity of 1, 32 can be dramatically improved, the temperature of the glass lens 12 can be finely adjusted by adjusting the internal temperatures of the molding dies 5, 6.
The surface accuracy of both surfaces of the molded glass lens is further improved, and high quality lenses can be manufactured with high productivity.

[0024]

According to the present invention having the above-mentioned structure, the heating and cooling means for the molding die are provided outside the molding die to perform heating and cooling through the heat conducting member. The heating and cooling corresponding to the shape and material of the mold, and the freedom to choose without the limitation of capacity and size of the equipment, wide temperature control inside the mold, and easy temperature equalization of the glass lens In particular, a convex lens, a concave lens, a meniscus lens, and the like have high surface accuracy on both surfaces, and have an effect of excellent productivity.

[Brief description of drawings]

FIG. 1 is a front sectional view showing the concept of a heating / cooling device in a mold of a glass lens molding device of the present invention.

FIG. 2 is a cross-sectional view from the front showing the main part of the heating / cooling device in the mold of the glass lens molding device according to the first embodiment of the present invention.

FIG. 3 is a front sectional view showing a modified example of the cooling unit of the heating / cooling device shown in FIG.

FIG. 4 is a cross-sectional view from the front showing a main part of only a lower mold according to a second embodiment of the heating and cooling device in the mold of the glass lens molding apparatus of the present invention.

5 is a cross-sectional view from the top surface of the heat conducting member taken along the line AA shown in FIG.

FIG. 6 is a cross-sectional view from the front showing a molding die for a conventional glass optical component.

FIG. 7 is a cross-sectional view from the front of a molding die apparatus similar to that used in the conventional method of manufacturing an optical element.

[Explanation of symbols]

 5 Upper mold 6 Lower mold 8,9 Thermocouple 12 Glass lens 13,14,31,32 Heat conduction member 15,16 Heating part 17,18 Cooling part 19,20 Outer peripheral heating part 21 Outer peripheral cooling blow 22,23 Heating / cooling member 24 Cooling Fin 25 Air Nozzle 28,29 Fixing Pin 33,34 Caulking Cap 35,36 Wick Net 38 Vertical Groove 39,40 Heat Dissipation Point (Vaporization Point) 41,42 Diffusion

Claims (3)

[Claims] 1. A pair of molding dies for press-molding a heat-softened glass gob, an in-mold heating / cooling section provided for heating / cooling the inside of the molding dies, and a heating / cooling section and a molding die. An in-mold heating / cooling device for a glass lens molding device, comprising: a heat conducting member. 2. The in-mold heating / cooling device of the glass lens molding apparatus according to claim 1, wherein the heating part and the cooling part are connected to the same heat conducting member. 3. The in-mold heating / cooling device of the glass lens molding device according to claim 1, wherein the heat conducting member is a heat exchange heat pipe.