JP2012030414A - Method and apparatus for manufacturing mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a mold that can process a mold matrix by a general-purpose processing apparatus, even if a processing range is narrower than the area to be processed of the mold matrix.SOLUTION: The method for manufacturing the mold includes: a process which forms two or more alignment marks 144 on a surface to be processed of a mold matrix 200; and a process in which the area to be processed of the mold matrix 200 is partitioned into two or more regions 202, 204, 206, 208 of the size of at most a processing range 210 of a cutting device, the mold parent 200 is relatively moved to the processing range 210 of the cutting device by the partitioned area units, and the mold matrix 200 of each region is processed, wherein at least two of the two or more alignment marks 144 are contained in the processing range 210 of the cutting device before and after the relative movement.

Description

  The present invention relates to a mold manufacturing method and a mold manufacturing apparatus.

Conventionally, in the field of manufacturing optical lenses, a technique for obtaining an optical lens having high heat resistance by providing a lens portion made of a curable resin on a glass substrate has been studied (for example, see Patent Document 1).
As an example of an optical lens manufacturing method to which this technology is applied, a so-called “wafer lens” is formed on a surface of a glass substrate, which is provided with a plurality of lens parts made of an optical member made of a curable resin, and then each lens part A method of cutting a glass substrate is used.
A metal mold (mold) is often used to mold a resin lens part on a glass substrate or to manufacture a resin transfer mold for molding a wafer lens. In addition to the shape of the concave and convex portions being accurately formed in the mold used for manufacturing the wafer lens, so that the lens portion obtained by molding satisfies the optical performance intended by the designer, It is required that the concave portions and the convex portions are regularly arranged so that the steps after molding the lens portion (for example, lamination with another optical member) can be performed with high accuracy.

Japanese Patent No. 3926380

In this case, a concave or convex portion corresponding to the lens shape is formed in the mold by a general-purpose cutting device, but the mold corresponding to the wafer lens is currently as large as 8 inches (φ200 mm). When processing is performed on a large-diameter mold base for obtaining a mold, a general-purpose cutting apparatus has a processing range narrower than the processing target area of the mold base, and cannot handle the processing of a large-diameter mold base. Of course, it is conceivable to introduce a large cutting device corresponding to the wafer size to cope with the processing of the large-diameter mold base, but such a large cutting device is very expensive and requires a small installation space. It is necessary to secure a large amount.
Accordingly, a main object of the present invention is to provide a mold manufacturing method capable of processing a mold base with a general-purpose processing apparatus even if the processing range is narrower than the processing target area of the mold base. is there.

In order to solve the above problems, according to the present invention,
A method for manufacturing a mold, wherein the mold base is processed using a cutting device having a processing range smaller than the size of the work surface of the mold base,
Forming a plurality of alignment marks on the work surface of the mold base;
The work area of the mold base is divided into a plurality of areas having a size less than or equal to the processing range of the cutting apparatus, and the mold base is relative to the processing range of the cutting apparatus in units of the divided areas. And processing the mold base in each region, and
At least two of the plurality of alignment marks are included in a processing range of the cutting apparatus before and after the relative movement, and a method for manufacturing a mold is provided.

  According to the present invention, a plurality of alignment marks are formed on a work surface of a mold base, a region to be processed of the mold base is divided into a plurality of areas, and the mold base is cut in units of the divided areas. It is moved relative to the processing range of the apparatus to process the mold base in each region. Since at least two of the plurality of alignment marks are included in the machining range of the cutting device before and after the relative movement between the mold base and the machining range of the cutting device, machining can be performed easily and accurately. It can be carried out. Therefore, even if the processing range of the cutting device is narrower than the processing target area of the die base, a large-diameter die can be manufactured with high accuracy by a general-purpose cutting device.

It is a perspective view which shows schematic structure of a concave mold. It is sectional drawing which follows the II line | wire of FIG. It is the (a) perspective view (b) partial enlarged view which shows schematic structure of a cutting device. It is the (a) perspective view (b) partial enlarged view which shows the modification of the cutting device of FIG. 3A. It is (a) top view (b) side view which shows schematic structure of a ball end mill. It is a top view which shows the modification of the cutting blade of FIG. It is (a) top view (b) side view which shows the modification of the cutting blade of FIG. It is the schematic which shows the manufacturing method of a metal mold | die over time. It is drawing for demonstrating the mode of a finishing process roughly. It is a top view for demonstrating schematically the aspect of an alignment mark. It is a microscope picture of an alignment mark, and is a drawing showing (a) before burr removal and (b) after burr removal. It is an external view which shows an example of a large diameter metal mold | die. It is drawing for demonstrating schematically the manufacturing method of a large diameter metal mold | die.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
First, in order to facilitate understanding, a basic processing procedure will be described using a simple mold as an example.

[Mold]
As shown in FIG. 1, the mold 100 has a substantially rectangular parallelepiped shape, and a plurality of concave portions 102 (cavities) are formed in an array on the surface. The mold 100 is an example of an array lens mold, and is particularly preferably used for molding a resin lens portion of a wafer lens. It can also be used when manufacturing a resin transfer mold for molding a wafer lens.

When the cross section of one block in which the concave portion 102 is formed is viewed in detail, as shown in FIG. 2, the flat portion 104, the inclined portion 106, the flat portion 108, the inclined portion 110, and the flat portion 112 are formed around the concave portion 102. These parts are formed concentrically around the recess 102 in order. An optical axis (optical axis of an optical element molded using a mold 100 or a resin transfer mold manufactured by the mold 100) is orthogonal to the center of the recess 102.
Note that the cross-sectional shape shown in FIG. 2 is merely an example, and an arbitrary shape that matches the intended application and optical performance may be used. For example, in FIGS. 1 and 2, the portion corresponding to the lens portion is formed as a plurality of spherical concave portions 102. However, a convex portion or an aspherical shape is formed according to the shape of the lens to be finally obtained. Good.
The shape of the mold 100 is not limited to a substantially rectangular parallelepiped, but may be a substantially cylindrical shape, a divided circle shape, or a disk shape.

[Cutting equipment]
As shown in FIG. 3A (a), the cutting device 120A has a surface plate 122. On the surface plate 122, a stage 124 having an orthogonal axis and a turning axis is provided. The stage 124 is held on a two-stage slide plate with a built-in drive mechanism, is movable along the X-axis direction and the Z-axis direction, and is a circle centering on an axis parallel to the Y-axis (B-axis). Can be rotated in the circumferential direction (direction B). A spindle 126 is installed on the stage 124. The surface plate 122 is provided with a fixture 128 for fixing the object to be cut (work material) 140. On the surface plate 122, the spindle 126 and the fixture 128 are disposed to face each other. The fixture 128 is held by a slide member having a built-in drive mechanism and is movable in the Y-axis direction, so that the spindle 126 and the cutting object 140 can move relative to each other. The fixing tool 128 is configured to be fixed and unfixed with respect to the slide member moving in the Y-axis direction. When the fixing is released, the fixing tool 128 is centered on a rotation axis parallel to the Z-axis direction. It can be rotated in the direction.

  The cutting device 120 </ b> A has an observation mechanism for observing the work surface of the cutting target 140 fixed to the fixing unit 128. The observation target region of the observation mechanism is associated with the processing range of the cutting device 120A. After confirming the position of the cutting object 140 with the observation mechanism and determining the initial position of the fixed part 128, each part operates according to the control program, and the cutting object 140 is processed accurately based on the initial position. go. A scale or a reference line is provided in the observation field of the observation mechanism so as to coincide with the horizontal direction and the vertical direction in the processing region. After an alignment mark (to be described later) is formed on the cutting object 140, the position of the fixing unit 128 of the cutting device is adjusted so that the alignment mark is included in the observation field of the observation mechanism. Make the scale or reference line almost coincide. And after fixing the position of the fixing | fixed part 128, the shift | offset | difference with the scale or reference line in an observation visual field, and an alignment mark is measured. The deviation measured in this way is fed back to the control at the time of cutting.

The spindle 126 has a built-in spindle motor. As shown in FIG. 3A (b), a ball end mill 132 is installed on the spindle 130 of the spindle motor. The ball end mill 132 is an example of a cutting tool.
The spindle 126 provided with the ball end mill 132 is preferably a spindle having an air bearing in order to process the optical surface with high accuracy. The power for rotating the spindle 126 includes a spindle motor system that incorporates a spindle motor and an air turbine system that supplies high-pressure air. As the power, it is desirable to adopt a spindle motor system for high rigidity.

Note that the cutting device 120B of FIG. 3B may be used instead of the cutting device 120A of FIG. 3A.
As shown in FIG. 3B (a), the cutting device 120B includes a spindle 126 (ball end mill 132) in a circumferential direction (A direction), Y axis and A axis of a circle centering on an axis (A axis) perpendicular to the Y axis. Can also be rotated in the circumferential direction (C direction) of a circle centered on an axis perpendicular to the axis (C axis). The rotation axes A, B, and C are orthogonal to each other. Other configurations of the cutting device 120B are the same as those of the cutting device 120A (see FIG. 3B (b)).
According to the cutting device 120B, the ball end mill is configured so that the normal to the edge contour at an arbitrary point of the tip edge of the ball end mill 132 (such as a cutting edge 134 described later) and the normal to the processing surface are always parallel. The posture of 132 can be controlled. As a result, machining can be performed at one point of the tool edge, and the influence of the tool edge contour error on the machining shape can be reduced.

As shown in FIG. 4, a cutting blade 134 is brazed and fixed to the tip of the ball end mill 132. The cutting blade 134 is a diamond tip made of single crystal diamond.
When the cutting blade 134 is viewed in plan, as shown in FIG. 4A, the cutting blade 134 has an arc portion 134a and a straight portion 134b. When the cutting blade 134 is viewed from the side, as shown in FIG. 4B, the cutting blade 134 has straight portions 134c, 134d, and 134e. The arc portion 134a and the straight portions 134b to 134e correspond to ridge lines where the respective planes constituting the cutting blade 134 intersect.

In the spindle 126, when the spindle motor rotates, the cutting blade 134 rotates while drawing a hemispherical locus in conjunction with the rotation (see the two-dot chain line in FIGS. 4A and 4B). In this case, the contact point of the arc portion 134 a and the straight portions 134 b, 134 c, 134 d is the rotation center portion 134 f of the spindle 126, and the rotation center portion 134 f does not substantially move due to the rotation of the spindle 126.
In addition, as the cutting blade 134 rotates, the drive mechanisms in the Y-axis, X-axis, and Z-axis directions cooperate to rotate the ball end mill 132 in a spiral shape around the Z-axis direction. (See FIGS. 3A (b) and 3B (b)).

  As shown in FIG. 4, the cutting blade 134 is disposed on the rotation axis 250 (rotation center axis) of the ball end mill 132. Among the cutting blades 134, the rotation center part 134 f is disposed on the rotation shaft 250.

Instead of the cutting blade 134 of FIG. 4, the cutting blade 136 of FIG. 5 may be used.
As shown in FIG. 5, the cutting blade 136 has straight portions 136a and 136b, an arc portion 136c, and straight portions 136d and 136e. It is bent from the straight line part 136a to the straight line part 136b, and is bent from the straight line part 136b to the straight line part 136d via the arc part 136c. The straight portion 136d is bent from the straight portion 136e, and the rotation shaft 250 is arranged at a position intersecting with the straight portion 136e.
The straight portion 136d is a portion corresponding to a so-called bottom blade, and forms a certain angle θ with the surface having the rotation axis 250 as a normal line. The angle θ satisfies the condition of the expression (1), assuming that the angle parallel to the surface having the rotation axis 250 as a normal line is 0 °.
−0.9 ° ≦ θ ≦ + 0.9 ° (1)
When the cutting blade 136 is used for cutting, the relationship between the cutting speed F (mm / min (minutes)) of the cutting blade 136 and the rotational speed S (rpm) of the spindle 126 satisfies the condition of Expression (2). Satisfies.
S> (F / 0.00005) × | tan θ | (2)
The relationship between the width W1 of the straight portion 136d and the width W2 of the rotation radius (the distance from the rotation shaft 250 to the end of the straight portion 136d) satisfies the condition of the expression (3).
W2−W1 ≧ 1 μm (3)

Instead of the cutting blade 134 of FIG. 4, the cutting blade 138 of FIG. 6 may be used.
When the cutting blade 138 is viewed in plan, the cutting blade 138 has a straight portion 138a, an arc portion 138b, and a straight portion 138c, as shown in FIG. The rotation shaft 250 is arranged at a position intersecting with the straight line portion 138c. When the cutting blade 138 is viewed from the side, the cutting blade 138 has straight portions 138d, 138e, 138f, an arc portion 138g, and a straight portion 138h as shown in FIG.

[Mold manufacturing method]
As shown in FIG. 7, the mold 100 is manufactured through the following steps (a) to (g).
(A) A cutting object (die base) 140 is prepared and blank processing is performed on a predetermined region.
(B) An electroless nickel phosphorous plating process is performed on a predetermined region of the cutting object 140 to form a plating layer 142.
(C) The surface (plating layer 142) of the cutting object 140 is roughly processed using a general-purpose machining center to form an original shape (uneven shape) such as the recess 102.
(D) The surface of the cutting object 140 after rough machining is polished and smoothed.
(E) Finishing the recess 102 and the like using a diamond cutting blade.
(F) The surface of the cutting object 140 is planarized to form a reference surface, and an alignment mark 144 is formed on the reference surface.
The reference plane is a plane that serves as a reference when adjusting the height position with another member.
As will be described later, the alignment mark 144 is used to align the processing range of the cutting devices 120A and 120B with the processing target region of the mold 100.
The alignment mark 144 may be used for other purposes, for example, alignment with other members, alignment between the molded product of the mold 100 and other members, or the like.
Depending on the surface state of the processed surface (reference surface), polishing for smoothing the surface is performed after the steps (e) and (f).
(G) The cutting object 140 is washed to remove processing wastes, and a base layer such as a SiO ₂ film is formed on the surface of the cutting object 140 and a release agent is applied.
The SiO ₂ film functions as a base when applying the release agent. The SiO ₂ film is formed by any of vapor deposition, CVD, and sputtering. In order to form a SiO ₂ film with a uniform thickness on the surface of the cutting object 140, it is desirable to perform a CVD process.
The mold release agent facilitates mold release from the mold 100.

In the step (e), the cutting device 120A is basically used.
As shown in FIG. 3A (b), the spindle motor of the spindle 126 is operated to rotate the ball end mill 132 at a high speed. At the same time, the movement of the stage 124 in the X-axis direction and the Z-axis direction and the movement of the fixture 128 in the Y-axis direction are cooperated to rotate the ball end mill 132 with respect to the workpiece 140. That is, the ball end mill 132 is swirled while rotating to finish the surface of the recess 102.

In this case, as shown in FIG. 8, from the outermost region 154 through the region 152 to the central region 150, the ball end mill 132 is swirled in a spiral shape while being rotated while being held in a state parallel to the optical axis. A part or the whole of the concave portion 102 and the flat portion 104 is processed by contact.
A region 150 is a central portion of the recess 102 and includes a region orthogonal to the optical axis.
A region 152 is a region adjacent to the region 150 around the recess 102.
The region 154 is a region that is part or all of the flat portion 104 and is adjacent to the region 152.

In the step (e), the cutting device 120B may be used.
When the cutting device 120B is used, the spindle motor of the spindle 126 is operated and the ball end mill 132 is rotated at a high speed, as shown in FIG. 3B (b), similarly to the case where the cutting device 120A is used. At the same time, the movement of the stage 124 in the X-axis direction and the Z-axis direction and the movement of the fixture 128 in the Y-axis direction are cooperated to rotate the ball end mill 132 with respect to the workpiece 140.
At this time, while rotating the ball end mill 132 also in the A-axis and C-axis directions, the ball end mill 132 is swirled so as to be always processed at one point of the tool cutting edge (cutting blades 134 and 136), and the concave portion 102 or the flat portion 104 is thereby rotated. , 108, 112 are finished.

Also in the process (f), the cutting devices 120A and 120B are used.
In this case, the cutting blade 134 is replaced with the cutting blade 136 shown in FIG. 5, and the ball end mill 132 is rotated while rotating, so that the surfaces of the flat portions 104 (remaining regions excluding the finished region), 108, 112 are flat (smooth). ) Process.
According to the above cutting blade 136, since it has a special shape, it is possible to form a smooth surface excellent in specularity while suppressing an increase in tool radius and processing time. That is, theoretically generated irregularities can be suppressed to 50 nm or less, and the flat portions 104, 108, 112 can be processed with high accuracy and high efficiency. As a result, the mirror surface portion of an optical element such as a lens formed from the concave mold 100 is made highly accurate, and dirt or resin (resin transferred from the concave mold 100, etc.) on the flat portions 104, 108, 112 is attached. Can be reduced.

Thereafter, as shown in FIG. 9A, a cross-shaped alignment mark 144 (groove) having a certain line width is formed on the plane portion 112. In the alignment mark 144, the intersection of the center lines of the vertical line width and the horizontal line width is used for alignment.
When forming the alignment mark 144, the cutting blade 136 is replaced with the cutting blade 138 of FIG. 6, and the ball end mill 132 is rotated and moved linearly along the forward direction 146 (solid line portion) of FIG. 9B. . Thereafter, the ball end mill 132 is moved along the reverse direction 148 (dotted line portion) opposite to the forward direction 146 so as to follow the movement locus in the forward direction 146 while rotating without changing the rotation direction.
In the movement along the forward direction 146, it is assumed to be downcut (cutting in which the moving direction of the cutting blade 138 at the portion facing the workpiece and the relative moving direction of the cutting blade 138 with respect to the workpiece are reversed), and the reverse direction The movement along 148 is an upcut (cutting in which the moving direction of the cutting blade 138 at a portion facing the workpiece and the relative moving direction of the cutting blade 138 with respect to the workpiece are forward).

When the ball end mill 132 is moved only in the forward direction 146, as shown in FIG. 9C, the processed surface 160 formed by the movement of the ball end mill 132 in the forward direction 146 has minute irregularities (so-called burrs 162). In this case, the burr 162 is removed by moving in the reverse direction 148 as well.
In this case, the ball end mill 132 is moved with a space 164 between the tip of the cutting blade 138 and the machining surface 160 (with the cutting blade 138 slightly lifted). The interval 164 is preferably about 20 nm.

  Looking at the micrograph when the alignment mark 144 is actually formed, when the ball end mill 132 is moved only in the forward direction 146, a burr 162 is formed on the side edge of the alignment mark 144 as shown in FIG. It can be seen that is formed. On the other hand, when the ball end mill 132 is also moved in the reverse direction 148, it can be confirmed that the burr 162 is sufficiently removed as shown in FIG.

  According to the cutting method for forming the alignment mark 144 described above, since the ball end mill 132 is moved in the forward direction 146 and then moved in the reverse direction 148 so as to follow the movement locus thereof, FIG. As shown in FIG. 5, the burr 162 can be sufficiently removed (suppressed to 20 nm or less corresponding to the interval 164), and the formation surface (processed surface) of the alignment mark 144 can be processed with high accuracy. As a result, it is possible to reduce the adhesion of the resin, which is a problem in the resin transfer process using the mold 100. Further, since the shape of the alignment mark 144 becomes accurate, it becomes easy to accurately align the processing range of the cutting devices 120A and 120B and the processing target region of the mold base.

[Large diameter mold]
As shown in FIG. 11, the mold 300 in plan view has a larger diameter than the mold 100 (see FIG. 1) and has a wafer shape. The mold 300 is formed with a plurality of recesses 102 in a matrix, and the mold 300 has more recesses 102 than the mold 100.
Similar to the mold 100, a plane portion 104, a slope portion 106, a plane portion 108, a slope portion 110, and a plane portion 112 are concentrically formed between the recesses 102.

There are four regions where the recess 102 is not formed in the central portion of the mold 300, and one alignment mark 144 is formed in each region. That is, the four alignment marks 144 are arranged along the rows and columns of the recesses 102 arranged in a matrix.
In addition, about the alignment mark 144, not only what was shown to this embodiment but a various aspect is employable. For example, a plurality of alignment marks 144 may be formed in four regions where the recess 102 is not formed. Alternatively, the recesses 102 may be formed in all regions, and the alignment mark 144 may be formed between the adjacent recesses 102. When the alignment mark 144 is formed in a region where the recess 102 is not formed, the alignment mark 144 is easily formed. When the recesses 102 are formed in all the regions and the alignment marks 144 are formed between the adjacent recesses 102, more lens portions can be formed.

The mold 300 is manufactured by processing the mold base 200 with the cutting devices 120 </ b> A and 120 </ b> B in the same manner as the mold 100, but the processing range is narrower than the planar area of the mold base 200. / 4 or so.
Note that the number of the recesses 102 in the mold 300, the size of the diameter of the recess 102 with respect to the diameter of the mold 300, and the like are merely examples, and can be arbitrarily determined according to the application and required optical performance.

[Manufacturing method of large diameter mold]
The manufacturing method of the mold 300 is basically the same as the manufacturing method of the mold 100 and is different in the following points.
Cutting apparatuses 120 </ b> A and 120 </ b> B are used as manufacturing apparatuses for the mold 300.
Since the mold base 200 has a large diameter and the processing range 210 of the cutting devices 120A and 120B is about 1/4 of the mold base 200, as shown in FIG. Is divided into four areas 202, 204, 206, and 208, and the processes of steps (e) and (f) in FIG. 7 are divided into four times and repeated for each of the areas 202, 204, 206, and 208.
However, the alignment mark 144 is formed only in the first step in the step (f).
7A and 7B are collectively performed on the four regions 202, 204, 206, and 208, and the steps (c) to (f) are divided into four times. Alternatively, the process may be repeated for each of the regions 202, 204, 206, and 208 (in this case, the alignment mark is not formed in the step (f) after the second time).

At the first time, as shown in FIG. 12A, the region 202 included in the processing range 210 and the concave portion 102 around the region 202 are processed, and one alignment mark is provided for each of the regions 202, 204, 206, and 208. 144 is formed.
In the second time, as shown in FIG. 12B, the mold base 200 is rotated by ¼ with respect to the processing range 210 to process the concave portion 102 of the region 204 included in the processing range 210. Here, the fixing tool 128 of the cutting devices 120A and 120B is unfixed and rotated in the D direction around a rotation axis parallel to the Z axis, so that the machining range 210 of the mold base 200 and the cutting devices 120A and 120B is obtained. And move relative to each other. In this case, a mechanism for rotating the fixture 128 serves as a moving unit. If the mechanism is provided with a clutch or the like so that the rotation advances every predetermined angle, the setting of the fixture 128 for the second and subsequent times becomes easy. Of course, the mold base 200 may be once removed and rotated by ¼, and then attached to the cutting devices 120A and 120B again.

After relatively moving the mold base 200 and the processing range 210 of the cutting devices 120A and 120B, the alignment mark 144 formed on the mold base 200 is observed by the observation device of the cutting apparatuses 120A and 120B. Then, the scale or reference line in the observation field is compared with the alignment direction of the alignment mark 144. If necessary, the position of the fixture 128 is adjusted so that the difference between the two becomes small. Thereafter, the amount of deviation is measured from the comparison result between the two, and the amount of deviation is corrected and fed back to the machining program so as to be processed.
If at least two alignment marks 144 along the direction in which the recesses 102 are arranged are included in the observation field, the amount of deviation can be grasped by comparison with a scale or reference line in the observation field. However, if four locations are provided as in this embodiment, there is an advantage that the method of detecting the deviation amount can be made common each time.
By doing so, the alignment mark 144 of the region 204 substantially matches the position where the alignment mark 144 of the region 202 was present, and the deviation between the two is fed back so as to be corrected by the control program. Thus, the positioning of the mold base 200 and the processing range 210 of the cutting devices 120A and 120B when switching from the first time to the second time is substantially completed. According to the present embodiment, since the machining target region is switched by rotating the mold base 200 that is a workpiece, there is an advantage that a large space is not required around the cutting devices 120A and 120B when the processing target region is switched. There is.

In the third time, as shown in FIG. 12C, the mold base 200 is further rotated by ¼ to process the concave portion 102 of the region 206 included in the processing range 210.
Also in this case, the same procedure as the second time is performed so that the alignment mark 144 in the region 206 matches the position where the alignment mark 144 in the region 202 was present, and the mold base when switching from the second time to the third time is performed. 200 positioning is performed.
In the last fourth time, as in the second and third times, the mold base 200 is further rotated by 1/4 (the alignment mark 144 in the region 208 matches the position where the alignment mark 144 in the region 202 was present). Then, the mold base 200 is positioned), and the concave portion 102 of the region 206 included in the processing range 210 is processed. In this way, a large diameter mold 300 is obtained.
Thus, when the mold base 200 is moved by 1/4, a part of the machining range 210 of the cutting devices 120A and 120B overlaps before and after the movement, and the mold base corresponding to the overlapped machining range 210 is overlapped. A plurality of alignment marks 144 are formed in 200 processing target areas. Therefore, even if the mold base 200 is rotated, the alignment mark 144 is always included in the observation field of view of the cutting devices 120A and 120B. As a result, the processing is performed while the alignment mark 144 is always present in the processing range 210. Therefore, the alignment using the alignment mark 144 is possible each time the mold base 200 is moved, and accurate machining can be easily performed.

  According to the manufacturing method of the large-diameter mold 300 described above, the region to be processed of the mold base 200 is divided into four regions 202, 204, 206, 208 and aligned for each region 202, 204, 206, 208. However, since the mold base 200 is processed, even if the processing range 210 of the cutting devices 120A and 120B is narrower than the area of the mold base 200, the large-diameter size die base 200 is processed by the general-purpose cutting devices 120A and 120B. be able to. As a result, there is no need to introduce a large cutting device, and there is no need to consider introduction costs and installation space for the cutting device.

In addition, since the processing of the mold base 200 is performed four times as described above and the processing time tends to be long, in order to prevent the processing accuracy from being deteriorated due to the influence of environmental temperature changes, the mold A material having a low thermal expansion coefficient is preferably used as the material of 200.
The processing area of the mold base 200 is not limited to the four areas 202, 204, 206, and 208, and may be divided into the number of areas corresponding to the processing range 210.
In addition to the alignment mark 144 for positioning in the processing range 210 of the cutting devices 120A and 120B used in the second and subsequent processing, for another purpose (for example, for molding) from the first time to the last time. An alignment mark may be formed.

100 Mold 102 Recess (cavity)
104 Plane part 106 Slope part 108 Plane part 110 Slope part 112 Plane part 120A, 120B Cutting device 122 Surface plate 124 Stage 126 Spindle 128 Fixing tool 130 (Spindle motor) Spindle 132 Ball end mill 134 Cutting blade 134a Arc part 134b Linear part 134c , 134d, 134e Straight portion 134f Center of rotation 136 Cutting blade 136a, 136b Straight portion 136c Arc portion 136d, 136e Straight portion 138 Cutting blade 138a Straight portion 138b Arc portion 138c Straight portion 138d, 138e, 138f Straight portion 138g Straight portion 138g Part 140 Object to be cut (die base)
142 Plated layer 144 Alignment mark 146 Forward direction 148 Reverse direction 150, 152, 154 Region 160 Processing surface 162 Burr 164 Interval 200 Mold base 202, 204, 206, 208 Region 210 Processing range 300 Large diameter mold

Claims (10)

A method for manufacturing a mold, wherein the mold base is processed using a cutting device having a processing range smaller than the size of the work surface of the mold base,
Forming a plurality of alignment marks on the work surface of the mold base;
The work area of the mold base is divided into a plurality of areas having a size less than or equal to the processing range of the cutting apparatus, and the mold base is relative to the processing range of the cutting apparatus in units of the divided areas. And processing the mold base in each region, and
At least two of the plurality of alignment marks are included in a processing range of the cutting apparatus before and after the relative movement.   The mold manufacturing method according to claim 1, wherein the position adjustment of the cutting device with respect to the mold base is performed using the at least two alignment marks after the relative movement.   The mold manufacturing method according to claim 1, wherein the alignment mark is formed on the surface to be processed of the mold base so as to correspond to each of the divided regions.   The said alignment mark is a manufacturing method of the metal mold | die as described in any one of Claims 1-3 formed on the said metal mold | die base body by reciprocating a cutting blade.   The mold manufacturing method according to claim 1, wherein the relative movement is performed by rotating the mold base around a rotation axis perpendicular to a surface to be processed.   The mold manufacturing method according to claim 5, wherein the plurality of alignment marks are formed in the vicinity of the rotation shaft.   The manufacturing method of the metal mold | die as described in any one of Claims 1-6 which processes the whole to-be-processed area | region of the said metal mold | die base | substrate by repeating the said relative movement and the process of the said metal mold | die base body.   A plurality of processed shapes arranged in a matrix are formed on the processing surface of the mold base by processing, and the at least two alignment marks are arranged along columns or rows of the matrix array of the processed shapes. The manufacturing method of the metal mold | die of Claim 7 currently performed.   Before and after the relative movement, a part of the processing range of the cutting device overlaps, and the plurality of alignment marks are formed in a processing target region of the mold base corresponding to the overlapping processing range. The manufacturing method of the metal mold | die as described in any one of Claims 1-8. A mold manufacturing apparatus having a processing range smaller than the size of the work surface of the mold base,
A ball end mill for forming a plurality of alignment marks on the work surface of the mold base;
A moving means for dividing a region to be processed of the mold base into a plurality of regions having a size equal to or smaller than the processing range, and moving the mold base relative to the processing range in units of the divided regions; ,
With
At least two of the plurality of alignment marks are included in the processing range before and after the relative movement.

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