JP2003246630A - Forming apparatus for glass and method of manufacturing glass formed goods - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a forming apparatus for glass having functions to detect the occurrence of the tilt of press shafts and to automatically correct the tilt. <P>SOLUTION: An upper mold 1 is attached to the tip of an upper shaft 5 and a lower mold 2 is attached to the tip of a lower shaft 6. The rear end of the lower shaft 6 is connected successively across a slider block 17, a triaxial load detector 15 and a shaft posture correcting unit 14 to a jack 12. An axial component Fz of the press load acting on the lower shaft 6 and components Fx and Fy in two orthogonal directions within the plane perpendicular to the shaft are detected by the detector 15. The unit 14 is controlled by using the values detected by the detector 15 as feedback signals in such a manner that the X direction component Fx and Y direction component Fy of the press load are made zero. As a result, the occurrence of the tilt between the upper and lower shafts 5 and 6 is prevented and the parallelism between the upper and lower molds 1 and 2 is assured. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding device for molded glass articles such as optical elements.

[0002]

2. Description of the Related Art FIG. 6 shows a schematic structure of a conventional glass forming apparatus.

The upper die 1 is attached to the tip of an upper shaft 5 via a heat insulating member 3. The lower mold 2 is attached to the tip of the lower shaft 6 via the heat insulating member 4. An infrared lamp unit 7 is arranged around the upper mold 1 and the lower mold 2. The rear end of the lower shaft 6 is connected to the front surface side of the slider block 17.

The shaft drive unit 10 comprises a motor 11 and a jack 12. The jack 12 is driven by the motor 11, and the tip of the moving shaft of the jack 12 is connected to the back side of the slider block 17 via the load cell 13. The slider block 17 is guided by a guide 18 and driven in the vertical direction. The rear end of the lower shaft 6 is connected to the front surface side of the slider block 17.

By driving the jack 12 with the motor 11, the slider block 17 and the lower shaft 6 move vertically. As a result, the molding material glass is press-molded between the upper mold 1 and the lower mold 2. At this time,
The press load is detected by the load cell 13.

(Problems of conventional apparatus) At the time of press molding,
For some reason, a slight inclination may occur between the upper shaft 5 and the lower shaft 6, and the parallelism between the upper and lower molds 1 and 2 may be distorted. Such a tilt is generally called a tilt. However, the conventional device is not provided with means for automatically detecting the occurrence of tilt.

There are various factors that cause tilt. This is due to the bending deformation of the structural parts due to the application of a press load, the thermal deformation of the structural parts due to heating to soften the glass of the forming material, and the error during assembly or processing of the parts. It is difficult to fully understand and control these factors.

For example, the molding temperature changes depending on the glass component, and the deformation amount also changes depending on the molding temperature. The higher the molding temperature, the greater the deformation of the part and the greater the amount of tilt. Further, the pressing load applied during molding also changes depending on the glass component or the shape of the molded product. If the press load changes, the amount of bending of each part also changes, and the amount of tilt also changes.

As a result, pressing is performed with the lower shaft tilted relative to the upper shaft. For example, when a flat plate is formed, parts having different thicknesses may be formed. Become. In high-precision lenses, which have been in increasing demand in recent years, prevention of tilt occurrence is an important issue. In particular, when a large number of small-precision high-precision lenses are simultaneously molded in one press, this becomes a very important problem.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the conventional glass forming apparatus, and an object of the present invention is to detect the occurrence of the tilt of the press shaft. An object of the present invention is to provide a glass molding device having a function of automatically correcting tilt.

[0011]

The glass forming apparatus of the present invention is a glass forming apparatus for pressing a glass forming material using a pair of molds to form one mold on the back side. A fixed shaft that supports the other mold, and a moving shaft that is arranged to face the fixed shaft and that supports the other mold from the back surface, and the moving shaft is driven to move the one mold to the other mold. A shaft driving device that presses a mold, and three axes that are provided at a connecting portion between the shaft driving device and the moving shaft and that detect an axial component of a press load acting on the moving shaft and a component in two orthogonal directions in a plane perpendicular to the shaft A load detecting device, and a shaft attitude correcting unit that is provided at a connecting portion between the shaft driving device and the moving shaft and adjusts a component of the press load in the two orthogonal directions are characterized by being provided.

According to the glass forming apparatus of the present invention, during press forming, the axial component of the press load acting on the moving shaft (referred to as the Z direction component) and the components in two orthogonal directions in the plane perpendicular to the shaft are provided. By detecting (the X-direction component and the Y-direction component), it is possible to detect the occurrence of the tilt of the press axis. In this way, the three-directional components of the press load are detected, and the detection results are used as feedback signals,
If the axis posture correction unit is controlled so that the X-direction component and the Y-direction component of the press load become zero, the occurrence of tilt can be prevented and the parallelism between the upper and lower molds can be secured.

For example, the three-axis load detecting device may be constituted by at least three load cells arranged in a plane perpendicular to the axis and a pedestal for holding these load cells at predetermined positions in the plane. it can. The triaxial load detecting device is inserted in series with the moving shaft at a connecting portion between the shaft driving device and the moving shaft, for example.

Similarly, the axis attitude correction unit is provided with at least three piezo elements arranged in a plane perpendicular to the axis.
And a pedestal that holds these piezo elements at a predetermined position in the plane. The shaft attitude correction unit is inserted in series with the moving shaft at a connecting portion between the shaft driving device and the moving shaft.

Preferably, the three-axis load detecting device is provided with four load cells arranged symmetrically in a plane perpendicular to the axis,
And a pedestal that holds these load cells at predetermined positions within the plane.

In this case, it is preferable that the axial attitude correction unit is provided with four piezo elements arranged axially symmetrically in a plane perpendicular to the axis, and these piezo elements, as in the above-mentioned triaxial load detection device. It is composed of a pedestal that holds the element in a predetermined position within the plane.

Further, the triaxial load detecting device may be constituted by three load cells arranged in a plane perpendicular to the axis and a pedestal for holding these load cells at predetermined positions in the plane. . In that case, for example, each load cell is arranged at a position where the distance from the central axis of the movement axis is equal to each other, and the first distance between the first load cell and the second load cell in the first direction is the first distance. Match the circumferential distance between the load cell and the third load cell.

In this case, it is preferable that the axial attitude correction unit includes three piezo elements arranged in a plane perpendicular to the axis, and these piezo elements, as in the above-mentioned three-axis load detecting device. It is configured by a pedestal that is held at a predetermined position in the plane, and each piezo element is arranged according to the same conditions as those of the load cell.

The three-axis load detecting device and the shaft attitude correcting unit as described above may be mounted on the fixed shaft side instead of on the moving shaft side.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a schematic structure of a glass molding apparatus of the present invention. In the figure, 1 is an upper mold, 2 is a lower mold,
5 is an upper shaft (fixed shaft), 6 is a lower shaft (moving shaft), 10 is an axis drive device, 12 is a jack, 14 is an axis posture correction unit,
Reference numeral 15 represents a triaxial load detection device, and 16 represents a control device. In FIG. 1, the Z axis is defined in the central axis direction common to the upper shaft 5 and the lower shaft 6, and the X axis and the Y axis are defined in two directions orthogonal to each other in a plane perpendicular to the Z axis.

The upper mold 1 is attached to the tip of the upper shaft 5 via the heat insulating member 3. The lower mold 2 is attached to the tip of the lower shaft 6 via the heat insulating member 4. An infrared lamp unit 7 is arranged around the upper mold 1 and the lower mold 2. The rear end of the lower shaft 6 is connected to the front surface side of the slider block 17.

The shaft driving device 10 comprises a motor 11 and a jack 12. The jack 12 is driven by a motor 11, and the tip of the moving shaft of the jack 12 has an axial posture correction unit 14 and a triaxial load detection device 15
Are sequentially connected to the back surface side of the slider block 17. The slider block 17 is guided by a guide 18 and driven in the vertical direction. The rear end of the lower shaft 6 is connected to the front surface side of the slider block 17.

By driving the jack 12 with the motor 11, the slider block 17 and the lower shaft 6 move vertically. As a result, the molding material glass is press-molded between the upper mold 1 and the lower mold 2.

At this time, the axial load component (Z-direction component: Fz) of the press load acting on the lower shaft 6 and the components in two orthogonal directions in the plane perpendicular to the shaft (X-direction component: Fx, Y-direction component). : Fy) is detected by the triaxial load detection device 15. The control device 16 uses the value detected by the triaxial load detection device 15 as a feedback signal to control the axial attitude correction unit 14 so that the X-direction component Fx and the Y-direction component Fy of the press load become zero. . This prevents the occurrence of tilt between the upper and lower shafts 5 and 6,
The parallelism between the upper and lower molds 1 and 2 can be secured.

FIG. 2 shows an example of the triaxial load detection device 15 used in the glass forming apparatus of the present invention. This triaxial load detection device includes four load cells 21a to 21d and a pedestal 22.
It is composed by. 4 load cells 21a-d
Are mounted on the pedestal 22 and arranged axially symmetrically in a plane perpendicular to the axis (Z direction).

FIG. 3 shows another example of the triaxial load detecting device 15 used in the glass forming apparatus of the present invention. This triaxial load detection device includes three load cells 31a to 31c and a pedestal 3
It is composed of two. Three load cells 31a-c
Are mounted on the pedestal 32 and arranged in a plane perpendicular to the axis (Z direction). Each load cell 31a-c
Are equal in distance from the central axis of the moving shaft 6 (FIG. 1) to each other, and the circumferential distance between the first load cell 31a and the second load cell 31b is the same as the first load cell 31.
It is equal to the circumferential distance between a and the third load cell 31c. In addition to the above-described example, a commercially available triaxial load detector (for example, three-component sensor 9067B manufactured by Nippon Kistler Co., Ltd.) can be used for the triaxial load detection device 15.

FIG. 4 shows an example of the axis posture correcting unit 14 used in the glass forming apparatus of the present invention. This axial attitude correction unit is a commercially available product (for example, P243 series manufactured by PII Polytec), and includes four piezo elements 41a to 41d and a pedestal 42. The four piezo elements 41a to 41d are mounted on the pedestal 42 and arranged axially symmetrically in a plane perpendicular to the axis (Z direction).

By individually controlling the voltage applied to each piezo element 41a-d, each piezo element 41a-41d is controlled.
The thickness of d is individually changed, thereby changing the inclination of the contact surface between the shaft attitude correction unit 14 and the triaxial load detection device 15 (FIG. 1), and the components of the press load in the X direction and the Y direction. Can be adjusted.

The piezo element has a high compressive strength and can be used even under a large press load. Moreover, the tilt amount of the press axis is usually very small, and the amount of height adjustment by each piezo element is 100 μm.
It is enough to anticipate about m.

FIG. 5 shows another example of the axial attitude correcting unit 14 used in the glass forming apparatus of the present invention. This axial posture correction unit is composed of three piezo elements 51a to 51c and a pedestal 52. Three piezo elements 51a
To c are mounted on the pedestal 52 and arranged in a plane perpendicular to the axis (Z direction). Each piezo element 51a
Are the same in distance from the central axis of the moving shaft 6 (FIG. 1), and the distance in the circumferential direction between the first piezo element 51a and the second piezo element 51b is the first piezo element. It is equal to the circumferential distance between the element 51a and the third piezo element 51c. Using the glass molding apparatus shown in FIG. 1, a commercially available triaxial load detector is used for the triaxial load detection device 15,
Using the apparatus in which the four piezo elements shown in FIG. 4 were incorporated in the axial posture correction unit 14, glass test molding was performed under the following molding conditions. That is, between the upper and lower molds,
Sixteen glass forming materials (2 mmφ × 3 mmh) were placed on an axis and heated to 600 ° C., and then the pressing load was increased stepwise from 300 kgf to 1000 kgf in steps of 100 kgf to form the forming material into a plate shape.

After press molding and cooling, the thickness of each glass molded product was measured. ± which occurred in the conventional device (Fig. 6)
The variation of 10μm is ± 1μ when this device is used.
It was about m.

In the example shown in FIG. 1, the triaxial load detecting device 15 and the axial attitude correcting unit 14 are inserted between the slider block 17 and the moving shaft of the jack 12, but the lower shaft 6 and the jack are not shown. Other positions may be used as long as they are in the middle of the drive sources such as 12. Also, other types of guide mechanisms for the lower shaft 6 can be used. However, from the viewpoint of controllability, it is desirable to dispose the triaxial load detection device 15 and the axial attitude correction unit 14 as close as possible.

In the above description, an example in which the triaxial load detecting device and the shaft attitude correcting unit are mounted on the moving shaft side has been described, but instead of this, it may be mounted on the fixed shaft side.

[0034]

According to the glass forming apparatus of the present invention, the three-direction components of the press load are detected, and the detection results are used as feedback signals to make the X-direction component and the Y-direction component of the press load zero. By controlling the shaft attitude correction unit in this manner, tilt of the press shaft is prevented from occurring, and parallelism between the upper and lower molds can be secured.

According to the apparatus of the present invention, the parallelism between the upper and lower molds can be automatically maintained in real time even when the molding conditions such as the molding temperature and the press load change. As a result, a molded product with high accuracy can be manufactured.

The apparatus of the present invention is particularly suitable for press molding a large number of small optical elements at the same time. According to the apparatus of the present invention, it is possible to enhance the uniformity of the thickness of each molded product, and improve the quality and yield.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a glass forming apparatus of the present invention.

FIG. 2 is a diagram showing an example of a triaxial load detection device used in the glass forming apparatus of the present invention.

FIG. 3 is a view showing another example of the triaxial load detection device used in the glass forming apparatus of the present invention.

FIG. 4 is a view showing an example of an axis posture correction unit used in the glass forming apparatus of the present invention.

FIG. 5 is a view showing another example of the shaft posture correction unit used in the glass forming apparatus of the present invention.

FIG. 6 is a view showing a schematic configuration of a conventional glass forming apparatus.

[Explanation of symbols]

1 ... Upper mold, 2 ... Lower mold, 3, 4 ... Insulation member, 5 ... upper shaft (fixed shaft), 6 ... Lower axis (moving axis), 7 ... Infrared lamp unit, 10 ... Axial drive device, 11 ... motor, 12 ... Jack, 13 ... load cell, 14 ... Axis posture correction unit, 15 ... 3-axis load detection device, 16 ... Control device, 17 ... Slider block, 18 ... Guide, 21a-d, 31a-c ... load cell, 22, 32 ... Pedestal, 41a-d, 51a-c ... Piezo element, 42, 52 ... Pedestal.

Continued front page    (72) Inventor Hidetoshi Kitahara             2068 Ooka, Numazu City, Shizuoka Prefecture Toshiba Machine Co., Ltd.             In the company

Claims (20)

[Claims] 1. A glass molding apparatus for pressing a glass molding material using a pair of dies to form a fixed shaft for supporting one of the molds from the rear surface, and a fixed shaft facing the fixed shaft. And a moving shaft that supports the other mold from the rear surface, a shaft driving device that drives the moving shaft and presses the other mold against the one mold, and a moving shaft driving device A three-axis load detection device that is provided at the connecting part of the shaft and that detects the axial component of the press load acting on the moving shaft and the components in two orthogonal directions in the plane perpendicular to the shaft, and the connection between the shaft drive and the moving shaft And a shaft posture correction unit that adjusts components of the press load in the two orthogonal directions, and a glass forming device. 2. The triaxial load detection device comprises at least three load cells arranged in a plane perpendicular to the axis, and a pedestal that holds these load cells at predetermined positions in the plane, The glass molding device according to claim 1, wherein the glass molding device is inserted in series with the moving shaft at a connecting portion between the shaft driving device and the moving shaft. 3. The triaxial load detection device is configured by four load cells arranged axially symmetrically in a plane perpendicular to an axis, and a pedestal for holding these load cells at predetermined positions in the plane. The glass molding apparatus according to claim 2, wherein: 4. The triaxial load detection device is configured by three load cells arranged in a plane perpendicular to the axis, and a pedestal for holding these load cells at predetermined positions in the plane, and each load cell. Are equal in distance from the central axis of the moving axis to each other, and in the circumferential distance between the first load cell and the second load cell, the circumferential distance between the first load cell and the third load cell is The glass forming apparatus according to claim 2, wherein the glass forming apparatus is equal to the distance. 5. The axis posture correction unit is composed of at least three piezo elements arranged in a plane perpendicular to the axis, and a pedestal for holding these piezo elements at predetermined positions in the plane, The glass molding device according to claim 1, wherein the glass molding device is inserted in series with the moving shaft at a connecting portion between the shaft driving device and the moving shaft. 6. The axial attitude correction unit is configured by four piezo elements arranged symmetrically in a plane perpendicular to an axis and a pedestal for holding these piezo elements at predetermined positions in the plane. The glass forming apparatus according to claim 5, wherein the glass forming apparatus is formed. 7. The axis posture correction unit is configured by three piezo elements arranged in a plane perpendicular to the axis, and a pedestal for holding these piezo elements at predetermined positions in the plane, The piezo elements have mutually equal distances from the central axis of the movement axis, and the distance in the circumferential direction between the first piezo element and the second piezo element is equal to the first piezo element and the third piezo element. The glass forming apparatus according to claim 5, wherein the distance is equal to the distance in the circumferential direction. 8. A method for producing a glass molded article, comprising pressing a molding material between one mold supported from the back by a fixed shaft and the other mold supported from the back by a moving shaft, The pressing load acting on the moving shaft is detected as an axial component and a component in two orthogonal directions in a plane perpendicular to the axis, and the detection result is used as a feedback signal to determine that the components in the pressing load are in the two orthogonal directions. A method for manufacturing a glass molded article, which comprises controlling a pressing load acting on the moving shaft so as to be zero. 9. The components of the press load in each direction are detected by using at least three load cells that are inserted in series between the moving shaft and its drive source and that are arranged in a plane perpendicular to the shaft. The method for producing a glass molded article according to claim 8, wherein 10. The at least three piezo elements, which are inserted in series between the moving shaft and its drive source, and which are arranged in a plane perpendicular to the shaft, of the components of the press load in the two orthogonal directions. It adjusts using, The manufacturing method of the glass molded article of Claim 8 characterized by the above-mentioned. 11. A glass molding apparatus for pressing a glass molding material using a pair of dies to form a fixed shaft for supporting one of the molds from the back surface, and a fixed shaft facing the fixed shaft. And a moving shaft that supports the other mold from the back, a shaft driving device that drives the moving shaft to press the other mold against the one mold, and a fixed shaft that is attached to the fixed shaft. A three-axis load detection device for detecting the axial component of the press load acting on the fixed shaft and the two orthogonal component in the plane perpendicular to the shaft, and the component of the press load attached to the fixed shaft in the two orthogonal directions. An apparatus for correcting glass posture, comprising: 12. The triaxial load detection device comprises at least three load cells arranged in a plane perpendicular to an axis, and a pedestal for holding these load cells at predetermined positions in the plane, The glass molding device according to claim 11, wherein the glass molding device is mounted in series with respect to a fixed shaft. 13. The triaxial load detection device is configured by four load cells arranged axially symmetrically in a plane perpendicular to the axis, and a pedestal for holding these load cells at predetermined positions in the plane. The glass molding apparatus according to claim 12, wherein the glass molding apparatus is a glass molding apparatus. 14. The triaxial load detection device is configured by three load cells arranged in a plane perpendicular to an axis and a pedestal for holding these load cells at predetermined positions in the plane, and each load cell. Are equal to each other in distance from the central axis of the fixed axis, in which the circumferential distance between the first load cell and the second load cell is equal to the circumferential distance between the first load cell and the third load cell. Glass forming apparatus according to claim 12, characterized in that it is equal to the distance. 15. The axis posture correction unit is configured by at least three piezo elements arranged in a plane perpendicular to the axis, and a pedestal for holding these piezo elements at predetermined positions in the plane, The glass molding apparatus according to claim 11, wherein the glass molding apparatus is mounted in series with respect to the fixed shaft. 16. The axial attitude correction unit is configured by four piezo elements arranged symmetrically in a plane perpendicular to the axis and a pedestal for holding these piezo elements at predetermined positions in the plane. The glass forming apparatus according to claim 15, wherein the glass forming apparatus is formed. 17. The axis posture correction unit is configured by three piezo elements arranged in a plane perpendicular to the axis, and a pedestal that holds these piezo elements at predetermined positions in the plane, The piezo elements are equal in distance from the central axis of the fixed axis, and the distance in the circumferential direction between the first piezo element and the second piezo element is equal to the first piezo element and the third piezo element. 16. The glass forming apparatus according to claim 15, wherein the distance is equal to the distance in the circumferential direction. 18. A method for producing a glass molded article, comprising molding a molding material by pressing a molding material between one mold supported from the back by a fixed shaft and the other mold supported from the back by a moving shaft, The press load acting on the fixed shaft is detected as an axial component and a component in two orthogonal directions in a plane perpendicular to the axis, and the detection result is used as a feedback signal to determine that the component in the two orthogonal directions of the press load is A method for manufacturing a glass molded article, which comprises controlling a pressing load acting on the fixed shaft so as to be zero. 19. The component of the press load in each direction is detected by using at least three load cells mounted in series with the fixed shaft and arranged in a plane perpendicular to the shaft. The method for producing a glass molded article according to claim 18. 20. Adjusting the components of the press load in the two orthogonal directions using at least three piezo elements mounted in series with the fixed shaft and arranged in a plane perpendicular to the shaft. The method for producing a glass molded article according to claim 18, wherein: