JP2007161508A - Method for machining mold for forming optical component, mold, and optical component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently improve the productivity and working precision of molds 1, 2 for forming an optical component (molds for press-forming a glass lens) in machining the molds 1, 2. <P>SOLUTION: By elliptically vibrating and cutting a mold material 12 (e.g. hard metal, silicon carbide, cobalt-base super heat-resistant alloy, nickel-base super heat-resistant alloy, and tungsten-base super heat-resistant alloy) by a cutting tool 11 (namely, by forming a locus 13 of elliptic vibration at the cutting edge of the cutting tool 11), molds for press-forming (chase blocks 4, 7) having press-forming surfaces 3, 6 corresponding to the shape of a glass lens are formed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention includes, for example, a molding die for an optical component that molds an optical component such as a glass lens and a plastic lens, and a processing method for a molding die for an optical component that processes the molding die, The present invention relates to an optical component molded with the mold.

  2. Description of the Related Art Conventionally, an optical component molding die for molding an optical component is processed by processing a mold material by a normal cutting method.

Hereinafter, as a conventional example, a press molding die (molding die for an optical component) of an optical component for press molding (compression molding) a glass lens (optical component) will be described as an example.
That is, a die material (work material) such as a brass material or steel material is cut with a cutting tool by a normal cutting method, so that the die (both upper and lower dies) needs to correspond to the shape of the lens described above. A press-molding surface (upper and lower cavity recesses) having the following shape is formed.
The above-mentioned glass lens is formed by supplying the glass material (glass bump) heated and melted between the upper and lower press-molding surfaces of the press-molding die and clamping the above-mentioned upper and lower press-molding surfaces. The above-mentioned molten glass material is formed by press molding (heat-press molding) in the upper and lower cavity recesses formed in (1).
That is, the shape of the glass lens described above is formed by transferring the required shape of the above-described mold press molding surface, and in the above-described mold, various shapes such as a free-form surface lens, an aspherical lens, a flat lens, etc. A lens having a shape is molded.

JP 10-166368 A

By the way, the glass lens described above is superior in optical properties such as high refractive index and weather resistance, and low birefringence and chromatic aberration, compared to plastic lenses obtained by injection molding a plastic material. The demand is increasing.
That is, as described above, with the aim of improving the optical performance of the lens, the glass material for forming the glass lens described above has a high melting point, for example, a glass material heated and melted at 400 ° C. to 1000 ° C. Has come to be used.
Therefore, a high melting point resistant material has been studied as a mold material for a press molding die for press molding the glass material heated and melted at the heating temperature described above.
For example, various mold materials such as cemented carbide and stellite alloy have come to be used, but all of them are difficult to cut in that the work surface of the mold material is processed into a fine shape. It is a material.
In particular, in the case of the above-mentioned stellite alloy, the internal structure is a dendrite layered structure that is a eutectic carbide segregated from the matrix and metal components, so that the surface tends to deteriorate when normally cut, and a predetermined surface roughness is obtained. A predetermined shape roughness cannot be obtained efficiently.
That is, in the point that the work surface to be cut of the mold material is processed into a fine shape, it cannot be processed efficiently by the normal cutting method.
Therefore, as a method of processing the mold for molding the lens having the various shapes described above, first, grinding (or normal cutting) is performed, and then polishing (lapping) is performed. (Hereinafter referred to as grinding and polishing method).

In recent years, with respect to glass lenses, the light passing through the lenses has become shorter in wavelength, and there is a growing demand for lenses having complicated and fine shapes. Further, production bases related to lenses have been moved to overseas. In light of this, the productivity of the above-mentioned molds such as automating the process of processing the press-molding mold for manufacturing the lens, and reducing the cost and shortening the delivery time of the above-mentioned mold, etc. Is required to be improved efficiently.
However, the shape of the lens described above becomes complicated and fine, and the conventional grinding and polishing method described above requires precise grinding and polishing with a reduced-diameter grindstone. There is an adverse effect that it takes time to manufacture the grindstone, and the productivity of the molding die cannot be improved efficiently.
In addition, the conventional grinding and polishing method relies on the ability of skilled workers to depend on the accuracy of the surface roughness and shape of the press-molded surface of the above-mentioned mold, so the reproducibility of the above-mentioned mold machining accuracy is reproducible. For example, in the processing accuracy of the above-described grinding / polishing process, non-uniform grinding scratch marks are likely to occur on the surface of the mold material described above.
Therefore, there is an adverse effect that the processing accuracy of the molding die described above cannot be improved efficiently.

Accordingly, the present invention provides a method of processing an optical component molding die capable of efficiently improving the productivity of the optical component molding die, the mold, and an optical component molded with the mold. The purpose is to do.
The present invention also provides a method of processing an optical component molding die capable of efficiently improving the processing accuracy of an optical component molding die, the mold, and an optical component molded with the mold. The purpose is to do.

  An optical component molding die processing method according to the present invention for solving the technical problem is an optical component molding die processing method for molding an optical component, wherein the mold material is subjected to elliptical vibration. An optical component molding die having a molding surface corresponding to the shape of the optical component is formed by cutting.

  In addition, an optical component molding die according to the present invention for solving the above technical problem is an optical component molding die for molding an optical component, and the mold material is subjected to elliptical vibration cutting. Thus, it has a molding surface corresponding to the shape of the optical component described above.

  In addition, the mold for molding an optical component according to the present invention for solving the technical problem described above includes a cemented carbide, silicon carbide, a cobalt-based superalloy, and a nickel-based superalloy as the mold material. And selected from tungsten-based superalloys.

  An optical component according to the present invention for solving the above technical problem is an optical component molded by a molding die for optical components, and is formed by performing elliptical vibration cutting on a mold material. It is characterized by being molded by a molding die for optical parts having a molding surface.

  That is, the present invention provides a method of processing an optical component molding die capable of efficiently improving the productivity of the optical component molding die, the mold, and the optical component molded with the mold. It has an excellent effect that it can be performed.

  The present invention also provides a method of processing an optical component molding die capable of efficiently improving the processing accuracy of an optical component molding die, the mold, and an optical component molded with the mold. It has an excellent effect that it can be performed.

FIG. 1 shows a glass mold (optical component) press molding die (optical component molding die).
FIG. 2 is a diagram for explaining a processing method of the mold (split mold) shown in FIG.
FIG. 3 shows a cutting tool used in the mold machining method shown in FIG.
FIG. 4 is a diagram for explaining the principle of the elliptical vibration cutting method which is the processing method shown in FIG.
Fig. 5 (1) and Fig. 5 (2) show other cutting tools.

(Glass for glass lens press molding and press molding method using the mold)
That is, the press-molding die shown in FIG. 1 is composed of an upper die 1 and a lower die 2 disposed opposite to the upper die 1 and not shown, Heating means for individually heating the upper and lower molds 1 and 2 to a predetermined temperature, and mold clamping means for clamping the both molds 1 and 2 with a predetermined clamping pressure (with a predetermined pressure) And a pressurizing means for pressurizing).
Further, the upper die 1 is provided with an upper chase block 4 (divided die) having an upper press molding surface 3 (upper cavity recess) on the upper die surface side and the upper chase block 4 detachably mounted. An upper holder block 5 is provided, and the lower die 2 is provided with a lower chase block 7 (divided die) having a lower press molding surface 6 (lower cavity recess) on the lower die surface side. ) And a lower holder block 8 for detachably mounting the lower chase block 7 described above.
Further, by clamping the above-described molds 1 and 2, the glass material 9 (glass bump) heated and melted on the above-described upper and lower molding surfaces 3 and 6 is supplied and set, and the glass lens is heated and pressed. The upper and lower cavity recesses (3, 6) for molding are formed.
Therefore, by supplying the glass material 9 heated and melted between the molding surfaces (upper and lower cavity recesses) 3 and 6 of both molds as described above, and heating and press-molding, the upper and lower cavity recesses (3.6 and 6) described above are formed. ), A glass lens corresponding to the shape of the upper and lower cavity cavities (3, 6) described above can be formed.
For example, the inner shape of the upper and lower cavity recesses (3, 6) is a concave curved surface corresponding to the shape of the glass lens (convex curved surface).

Further, the above-described mold 1.2 (divided molds 4 and 7) is configured to be processed by an elliptical vibration cutting method (see FIG. 4) described later.
Further, in the above-described elliptical vibration cutting, for example, the cutting tool 11 such as a cutting tool shown in FIG. 3 is used, and the tip shape thereof is a pointed shape having a tip angle θ, and usually a diamond tool is used. Used (pointed cutting tool).
Therefore, for example, as shown in FIG. 2, the chase block having the press-formed surface 3 (6) is obtained by performing the elliptical vibration cutting of the work material 12 (mold material) with the cutting tool 11. 4 (7) can be formed.
In FIG. 2, A indicates the cutting direction, B indicates the main component force direction, D indicates the back component force direction, and 13 indicates an elliptical vibration locus drawn by the tip of the cutting tool 11 described above. .

In addition, examples of the mold material (12) shown in FIG. 2 include cemented carbide, silicon carbide, stellite alloy (super heat-resistant alloy), and the like. However, this defect is eliminated by the above-described elliptical vibration cutting method.
Examples of the stellite alloy described above include a cobalt-based superalloy, a nickel-based superalloy, and a tungsten-based superalloy.

(Principle of elliptical vibration cutting method)
Next, elliptical vibration cutting will be described using the example shown in FIG.
That is, the example of the elliptical vibration cutting shown in FIG. 4 is a configuration in which a predetermined cutting thickness 14 in a work material 12 (mold material) such as a steel material or a difficult-to-cut material is cut by the cutting tool 11 described above. An elliptical vibration cutting device is used to elliptically cut the workpiece 12 described above.
The elliptical vibration cutting apparatus includes, for example, a piezoelectric element (not shown) that applies vibration to the cutting edge of the cutting tool 11 in the X direction or in the X direction, and the XY two directions. In the piezoelectric element for generating vibration, a sinusoidal voltage can be input separately at a predetermined voltage, a predetermined frequency (for example, an ultrasonic region), and a predetermined phase difference (for example, 90 degrees). It is configured.
Therefore, in the above-described elliptical vibration cutting device, the above-described cutting is performed by mechanically resonating and synthesizing the vibrations generated in the two directions of XY described above by inputting predetermined sine wave voltages to the respective piezoelectric elements. An elliptical vibration locus 13 having a predetermined period can be generated at the cutting edge of the tool 11.
In FIG. 4, the aforementioned X direction corresponds to the cutting direction A and the main component force direction B, and the aforementioned Y direction corresponds to the back component force direction D.

That is, as shown in FIG. 4, first, according to the elliptical vibration locus 13, the cutting material 11 is used to cut the work material 12 in the main component force direction B (left direction in the example), The cutting tool 11 is separated from the work material 12 in the back component force direction D (upward in the illustrated example).
At this time, the above-described chip 15 flows out in the chip outflow direction E by cutting from the workpiece 12 and pulling up the chip 15 in the back component force direction D (upward in the illustrated example) with the cutting tool 11. Therefore, compared with the normal cutting method, the frictional resistance against the above-described elliptical vibration cutting is reduced or reversed (negative frictional resistance).
That is, the cutting resistance of the work material 12 with respect to the cutting tool 11 is reduced, and the cutting force of the cutting tool 11 can be reduced, so that the machinability is improved.
Next, the cutting tool 11 is separated from the chips 15 in the main component force direction B (rightward in the example), and the cutting tool 11 is moved in the back component force direction D (downward in the example). That is, it is moved to the work material 12 side.
Therefore, the workpiece 12 can be automatically processed by elliptical vibration cutting by periodically vibrating the cutting tool 11 according to the locus 13 of the elliptical vibration. .
Further, the above-described cutting by the elliptical vibration can reduce the thickness of the chip 15, reduce the cutting resistance, and can perform mirror finishing as compared with the normal cutting method. There are advantages such as prolonging the life, improving the accuracy of the machining shape, suppressing flash, preventing chatter vibration, and reducing cutting heat.
Further, in the conventional normal cutting method, the workpiece 12 is cut in a compressed state with the cutting tool 11, so that the cutting resistance is high and the chips become compressed powder, Burrs are generated on the cut surface of the cutting material.
However, in the cutting method using elliptical vibration cutting, since the above-described chip 15 can be pulled upward with the above-described cutting tool 11, the cutting resistance is reduced, and the above-described chip 15 is continuously formed (for example, (Elongated shape) can be discharged (referred to as a continuous ductility mode), generation of flash can be suppressed, and the cutting surface of the workpiece 12 can be processed into a mirror surface.
Therefore, the above-described elliptical vibration cutting method does not require the polishing step shown in the conventional example, and the cutting surface of the workpiece 12 (mold material) is efficiently processed into a mirror surface (by one processing). In addition to the conventional grinding and polishing method including the normal cutting method, the process for processing the press molding dies 1 and 2 can be performed automatically and in a short time. It is configured.
Reference numeral 16 denotes a shear angle. When the shear angle is increased, the machinability of the work material 12 is improved.

That is, as described above, in the above-described elliptical vibration cutting method, the process of processing the press molds 1 and 2 is performed automatically and in a short time, and the mold material (work material) 12 is processed. Since it is configured so that the cutting surface can be efficiently processed into a mirror surface, it is possible to cope with the cost reduction and short delivery time of the molds 1 and 2 described above. The productivity of the molds 1 and 2 (split molds 4 and 7) can be improved efficiently.
Further, in the above-described elliptical vibration cutting method, the cutting surface of the mold material 12 can be efficiently processed into a mirror surface automatically and in a short time by the above-described elliptical vibration cutting device as compared with the conventional example. Therefore, it is possible to have the reproducibility of the processing accuracy of the above-mentioned press molding dies 1 and 2 without requiring a skilled worker, and the processing accuracy of the above-mentioned press molding dies 1 and 2 is efficient. It can be improved well.
In addition, since the cutting surface can be processed into a predetermined surface roughness or a predetermined shape roughness by a single processing using the above-described elliptical vibration cutting method by the elliptical vibration cutting device, for example, design such as correction processing The change can be dealt with efficiently and promptly, and also in this respect, the productivity of the press molds 1 and 2 can be improved efficiently.

(Glass lens press mold processing method)
That is, by using the above-described elliptical vibration cutting device, the above-described press molding is performed by automatically and short-time machining the above-described mold material 12 (the surface to be cut) with the above-described cutting tool 11. The chase blocks 4 and 7 having the surfaces 3 and 6 can be formed, and the press molding surfaces 3 and 6 are efficiently processed into mirror surfaces by the advantage of the above-described elliptical vibration cutting as compared with the conventional example. be able to.
Therefore, the upper and lower chase blocks 4 and 6 having the press-molding surfaces 3 and 6 are detachably mounted on the upper and lower holder blocks 5 and 8 respectively to form the molds 1 and 2. it can.
In addition, the above-mentioned glass molding lens 3 and 6 (mirror surface) is shape | molded by the said metal mold | die 1 and 2 by heat-press-molding the above-mentioned glass lens in the cavity recessed part (3 * 6) of the metal mold | die 1 * 2. The above lens surface can be formed into a mirror surface, and the optical performance of high refractive index and weather resistance, low birefringence and chromatic aberration can be efficiently achieved. A glass lens that can be improved can be obtained.

That is, as described above, a method of processing an optical component molding die capable of efficiently improving the productivity of an optical component molding die (glass lens press molding die) and the die In addition, an optical component molded with the mold can be provided.
In addition, a processing method of an optical component molding die that can efficiently improve the processing accuracy of an optical component molding die (glass lens press molding die), its mold, and its mold A molded optical component can be provided.
In addition, when the above-described elliptical vibration cutting is performed, a predetermined surface roughness and a predetermined shape roughness can be obtained on the cutting surface by one processing, so that the design change such as correction processing can be performed quickly and efficiently. In addition, it is possible to efficiently improve the productivity of the optical component molding die (glass lens molding die for glass) described above.
Note that the above-described correction processing is particularly effective for the above-described stellite alloy.

(Other cutting tools)
Further, in the above-described embodiment, the configuration using the cutting tool 11 having a pointed tip shape illustrated in FIG. 3 is exemplified, but the cutting tool 21 having a hemispherical tip shape illustrated in FIG. Alternatively, a configuration using a cutting tool 31 (flat tool) having a flat tip shape as shown in FIG.

That is, when the hemispherical cutting tool 21 shown in FIG. 5A is used, no plastic flow is seen on the cut surface of the work material 22 (mold material), and a uniform mirror surface is formed on the work surface. The result that it can process efficiently was obtained.
Further, when the above-described hemispherical cutting tool 21 is used, even if an attachment error or a vibration error occurs in the cutting tool 21 described above, the cross-sectional shape of the chips (or the cutting tool 21 and the work material 22 described above) The shape of the contact cross section) does not change greatly, and scratch marks or the like hardly occur.
Therefore, the work surface by the hemispherical cutting tool 21 described above can be efficiently formed into a mirror surface, and the processing accuracy of the shape of the work surface can be improved efficiently.
In FIG. 5 (1), the position of the hemispherical cutting tool 21 when there is no mounting error in elliptical vibration cutting is indicated by a solid line, and the mounting error (including vibration error) occurs in elliptical vibration cutting. The position of the hemispherical cutting tool 21 is indicated by a two-dot chain line, and 23 indicates an error angle between the two.
Further, regarding the contact cross section between the cutting tool 21 and the work material 22, the reference numeral 24 indicates a contact cross section when there is no attachment error, and 25 indicates the contact cross section when the attachment error occurs.
Therefore, as described above, the shapes of the contact cross sections 24 and 25 shown in FIG. 5A do not change significantly.

In addition, when the planar cutting tool 31 shown in FIG. 5 (2) is used, the work material 32 is caused by a slight mounting error and vibration error of the cutting tool as compared with the hemispherical cutting tool 21 described above. However, if there is no mounting error in the planar cutting tool 31, the feeding amount of the cutting tool 31 can be increased. Therefore, the above-described hemispherical cutting tool is used. Compared to 21, the cutting efficiency of the above-described planar cutting tool 31 can be improved efficiently.
In FIG. 5B, the position of the planar cutting tool 31 when there is no attachment error in elliptical vibration cutting is indicated by a solid line, and an attachment error (including vibration error) occurs in elliptical vibration cutting. The position of the planar cutting tool 31 is indicated by a two-dot chain line, and 33 indicates an error angle between the two.
Further, regarding the contact cross section between the cutting tool 31 and the work material 32, 34 indicates a contact cross section when there is no mounting error, and 35 indicates a contact cross section when the mounting error occurs.
Therefore, the shapes of the contact cross sections 34 and 35 shown in FIG.

  The present invention is not limited to the above-described embodiments, and can be arbitrarily changed and selected as needed within a range not departing from the gist of the present invention. It is.

  In the above-described embodiment, the glass lens press mold shown in FIG. 1 has been described as an example, but the optical component can be applied to other than glass lenses, for example, plastic lenses. The present invention can be applied to injection molding dies, resin sealing molding dies for light emitting diodes, and the like.

FIG. 1 is a schematic longitudinal sectional view schematically showing a mold for molding an optical component (a mold for press molding of a glass lens) according to the present invention. FIG. 2 is a schematic enlarged cross-sectional view for explaining a method of processing the molding die while schematically showing the molding die shown in FIG. 1 in an enlarged manner. FIG. 3 is a schematic enlarged perspective view schematically showing an enlarged cutting tool used in the processing method for processing the molding die shown in FIG. 2. FIG. 4 is a schematic front view for schematically explaining the processing method of the molding die according to the present invention. FIG. 5 (1) and FIG. 5 (2) are schematic sectional views schematically showing other cutting tools.

Explanation of symbols

1 Upper mold 2 Lower mold 3 Upper press forming surface 4 Upper chase block 5 Upper holder block 6 Lower press forming surface 7 Lower chase block 8 Lower holder block 9 Glass material 11 Cutting tool (pointed cutting tool)
12 Work material (mold material)
13 Trajectory of elliptical vibration 14 Cutting thickness 15 Chip 16 Shear angle 21 Hemispherical cutting tool (R bite)
22 Work material 23 Error angle 24 Contact cross section 25 Contact cross section 31 Plane-shaped cutting tool 32 Work material 33 Error angle 34 Contact cross section 35 Contact cross section A Cutting direction B Main component force direction D Back component force E Chip discharge direction θ Tip angle

Claims (4)

  An optical component molding die for molding an optical component, which has a molding surface corresponding to the shape of the optical component by performing elliptical vibration cutting of the mold material. A method for processing a mold for molding an optical component, characterized in that:   An optical component molding die for molding an optical component, wherein the mold material has a molding surface corresponding to the shape of the optical component by performing elliptical vibration cutting of the mold material. Mold.   The mold material is selected from cemented carbide, silicon carbide, cobalt-based superalloy, nickel-based superalloy, and tungsten-based superalloy for molding optical components according to claim 2 Mold. An optical component molded with an optical component molding die, wherein the optical component is molded with an optical component molding die having a molding surface formed by elliptical vibration cutting of a mold material. Optical component.

Images