JP2003094201A - Axially non-symmetric and aspherical machining machine, axially non-symmetric and aspherical machining method, and axially non-symmetric and aspherical workpiece - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an axially non-symmetric and aspherical machining machine by which the axially non-symmetric and aspherical machining of high accuracy can be carried out. SOLUTION: A machining machine used to form a machined face by moving a machining tool 3 relatively against a work-piece 2 while rotating the work- piece 2 mounted on a rotatable main shaft 4. This machine is provided with a stage 1 for moving the work-piece used to move the work-piece 2 in the radial direction of the main shaft 4 on a vertical plane to a rotational shaft 5 by synchronizing with a machining position, a stage 32 for moving in an X-direction used to change the position of the machining tool 3 and a stage 33 for moving in a Z-direction in accordance with the above machining position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axially asymmetric aspherical surface processing machine, an axially asymmetrical aspherical surface processing method and an axially asymmetrical aspherical surface workpiece for forming an axially asymmetrical aspherical surface of a workpiece having an axially asymmetrical aspherical surface. As an axially asymmetric aspherical surface processed product, it can be applied to, for example, a mold for injection molding of an optical component such as a plastic lens.

[0002]

2. Description of the Related Art FIG. 9 shows a method for performing aspherical surface processing.
As shown in (A), there is a method in which the workpiece 102 is rotated by the main shaft 104, and the workpiece 102 is scanned with the tool 103 in the X and Z directions in the drawing to perform aspherical surface machining. For example, Japanese Patent Laid-Open No. 4-141336 is known.

As another method, as shown in FIG. 10, there is a method of performing processing by three-dimensionally scanning a rotary tool 107 rotating around a rotary shaft 105 with a workpiece 106 fixed. . For example, Japanese Patent Laid-Open No. 10-16
The 6212 publication is known.

[0004]

However, in the case of the method shown in FIG. 9, it is possible to machine an axially asymmetric aspherical surface by synchronizing the relative position between the tool and the workpiece with the rotational position of the spindle. However, as shown in FIG. 9B, since the machining direction TP due to the rotation of the spindle at the machining point P and the tangent line L of the curve E to be machined at P are not always parallel to each other, the machining accuracy is inferior. was there.

Further, in the case of the method of FIG. 10, there is a high degree of freedom in the shape that can be machined, but since it is necessary to rotate the tool, it is impossible to machine a workpiece having a radius smaller than the radius of rotation of the tool. was there. Further, since it is difficult to increase the removal amount per unit time, there is a problem that the processing time becomes long.

Therefore, an object of the present invention is to provide an axially asymmetrical aspherical surface processing machine, an axially asymmetrical aspherical surface processing method and an axially asymmetrical aspherical surface processed product which can perform highly accurate processing of an axially asymmetrical aspherical surface. I am trying.

It is another object of the present invention to provide an axially asymmetrical aspherical surface processing method and an axially asymmetrical aspherical surface processed product capable of highly accurately processing an axially asymmetrical aspherical surface in a short processing time.

[0008]

In order to achieve the above object, the invention of claim 1 is to move a tool relative to a workpiece while rotating the workpiece mounted on a rotatable spindle. In a processing machine for forming a machining surface, a workpiece moving means for moving the workpiece in a radial direction of a spindle on a plane perpendicular to the rotation axis in synchronization with the machining position, and a tool position according to the machining position. And an asymmetric aspherical surface processing machine.

According to a second aspect of the present invention, in the axially asymmetric aspherical surface processing machine according to the first aspect, the workpiece moving means has two or more axes of movement attached to the spindle. This is an axially asymmetric aspherical surface processing machine characterized by using an object moving stage.

According to a third aspect of the present invention, in the axially asymmetric aspherical surface processing machine according to the second aspect, the workpiece moving stage is synchronized with the rotation axis of the spindle and the movement axis of the tool moving means. It is an axially asymmetric aspherical surface processing machine.

A fourth aspect of the present invention is the axially asymmetric aspherical surface processing machine according to the first aspect, wherein a single crystal diamond is used as the tool.

A fifth aspect of the present invention is the axially asymmetric aspherical surface processing machine according to the first aspect, wherein a rotary grindstone is used as the tool.

According to a sixth aspect of the present invention, there is provided a machining method for forming a machined surface by moving a tool relative to a workpiece while rotating the workpiece mounted on a rotatable spindle. Asynchronous with the position, the workpiece is moved in the radial direction of the main axis on a plane perpendicular to the rotation axis, and the tool position is also changed according to the machining position to perform asymmetric aspherical surface machining. Is an axially asymmetric aspherical surface processing method.

According to a seventh aspect of the present invention, in the axially asymmetric aspherical surface machining method according to the sixth aspect, the outer peripheral portion in which the movement amount of the workpiece is large is processed by rotating the main shaft more than the inner peripheral portion. This is an axially asymmetric aspherical surface processing method characterized in that

According to an eighth aspect of the present invention, in the axial asymmetric aspherical surface processing method according to the sixth aspect, the workpiece is approximated to the axial asymmetrical aspherical surface before performing the axial asymmetrical aspherical surface processing. It is an axially asymmetric aspherical surface processing method characterized by being processed into a spherical surface or an axially symmetric aspherical surface shape.

Further, the invention of claim 9 is an axially asymmetric aspherical surface processed product processed by the axially asymmetric aspherical surface processing method according to claim 6.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing the overall configuration of an axially asymmetric aspherical surface processing machine according to a first embodiment of the present invention. As shown in FIG. 1, this axially asymmetric aspherical surface processing machine
In a processing machine that moves a processing tool 3 relative to the workpiece 2 while rotating the workpiece 2 mounted on a rotatable spindle 4, and synchronizes with a processing position in a processing machine. A workpiece moving stage 1 that is a workpiece moving unit that moves the workpiece 2 in the radial direction of the spindle 4 on a plane perpendicular to the rotation axis 5 of the spindle 4, and a tool that changes the position of the machining tool 3 according to the machining position. And means of transportation. This tool moving means is a mounting block 3 for mounting the processing tool 3.
1, an X-direction moving stage 32 that moves the mounting block 31 in the X-direction, and a Z-direction moving stage 33 that moves the X-direction moving stage 32 in the Z-direction.
The Z-direction moving stage 33 is provided on the upper surface of the processing machine body 6 in this embodiment.

The workpiece moving stage 1 is mounted on the main spindle 4 and has two or more moving axes, and moves the workpiece 2 in the radial direction of the main spindle 4 on a plane perpendicular to the rotation axis 5. And is synchronized with the rotating shaft 5 of the main shaft 4 and the moving shaft of the tool moving means. In the present embodiment, the axially asymmetric aspherical surface processing machine performs cutting using a single crystal diamond tool as the processing tool 3.

FIG. 2 is a perspective view showing the overall construction of an axially asymmetric aspherical surface processing machine according to the second embodiment of the present invention. As shown in FIG. 2, the axially asymmetric aspherical surface processing machine according to the second embodiment is
Unlike the axially asymmetric aspherical surface processing machine of the first embodiment in that a rotating grindstone 13 is used as a processing tool instead of the single crystal diamond tool of the first embodiment, other configurations are the same as those of the first embodiment. It is similar to the spherical surface processing machine. Although the rotary grindstone 13 is used in FIG. 2, a rotatable cutting tool may be attached instead of the rotary grindstone 13 to perform fly-cut processing.

FIG. 3 is a view showing an example of axially asymmetrical aspherical surface processing by the axially asymmetrical aspherical surface processing machine shown in FIG. FIG. 3 shows, as an example of axially asymmetrical aspherical surface processing, processing of an axially asymmetrical aspherical surface shape in which a shape cut along a plane perpendicular to the rotation axis becomes an ellipse. In FIG. 3, reference numeral 8 indicates an axially asymmetric aspherical surface whose cross section along a plane perpendicular to the rotation axis becomes elliptical. Further, reference numeral O indicates a rotation axis that is the rotation center of the main shaft 4, reference numeral Ow indicates a point that satisfies the condition described later with reference to FIG. 4B, and reference numeral P indicates a processing point. Workpiece 2
Is moved by the workpiece moving stage 1 on the main axis 4 so that the center of an ellipse 7 described later comes to the point Ow.

FIG. 4A shows an axially asymmetric aspherical surface and a tool XZ.
FIG. 6B is a view seen in a cross section taken along a plane, and FIG. 6B is a view showing a processed region seen from the Z direction. In FIG. 4 (B), an ellipse 7 indicates a region to be cut when the position of the processing tool 3 is Z1 in FIG. 4 (A). The point P is a point where the ellipse 7 intersects the X axis, and the point P is machined by the machining tool 3 shown in FIG.

In FIG. 4B, reference numeral Ow indicates an ellipse 7 which can satisfy the condition that the tangent of the ellipse 7 at the machining point P is parallel to the Y axis and the curvature of the ellipse 7 at the machining point P is equal to OP. It shows the position of the center (the midpoint of the two focal points) of.

The workpiece 2 shown in FIG. 1 is positioned by the workpiece moving stage 1 so that the center of the ellipse 7 coincides with the point Ow, as shown in FIG. 4 (B). At that time, the machining point of the machining tool 3 shown in FIG.
As shown in, the X coordinate of the machining tool 3 is set so as to become the point P.

FIG. 5 is a diagram for explaining the processing of an elliptical shape. The elliptical shape shown in FIG. 5 is an ellipse represented by the equation (X ² / a ² ) + (Y ² / b ² ) = 1 and a = 1 and b = 0.8.

FIG. 6 shows a point Ow corresponding to the elliptical shape to be processed.
It is a figure which shows the locus | trajectory of. In FIG. 6, the intersection of the X axis and the Y axis is
It coincides with the rotating shaft 5 of the main shaft 4, which is the main rotating shaft. Reference numerals ~ shown in Fig. 6 denote points Ow at the time of processing the points of reference numerals ~ shown in Fig. 5. During processing, the workpiece 2 is moved by the workpiece moving stage 1 so that the center of the ellipse of the cutting area coincides with the position Ow.

FIG. 7 is a diagram showing a change in the X coordinate of the processing point P when the ellipse shown in FIG. 5 is processed. Each of the symbols to on the horizontal axis in FIG. 7 also corresponds to each of the symbols to in FIG. 5, as in FIG. The vertical axis of FIG. 7 shows the X coordinate of the point P.

FIG. 8 is a diagram showing the states of the point Ow and the processing point P during processing. In FIG. 8, reference numerals (1) to (4) show how the points corresponding to the reference numerals (1) to (5) in FIG. 5 are processed.
In addition, the points Ow at the respective positions are Ow1 to Ow.
3, the processing point P is described as P1 to P3.

FIG. 8A shows a state in which the major axis side of the ellipse is processed. In FIG. 8A, it can be seen that the center of the ellipse 7 moved so as to coincide with Ow1 is located in the + direction of the X axis rather than the rotation center O of the main axis.

FIG. 8B shows a state in which the portion between the major axis of the ellipse 7 and the minor axis of the ellipse 7 is processed. Figure 8
In (B), it can be seen that the center of the ellipse 7 moved so as to coincide with Ow2 is in the + direction of the Y axis.

FIG. 8C shows a state in which the minor axis side of the ellipse 7 is processed. In this case, the center of the ellipse 7 moved so as to coincide with Ow3 is X more than the rotation center O of the main axis.
It can be seen that it is in the-direction of the axis. Further, the distances from the rotation center O of the main shaft to the processing point P are Op1, Op2,
If Op3 is set, the relationship of Op1 <Op2 <Op3 is established.

It is necessary to move the work piece 2 shown in FIG. 3 with respect to the rotation center O so that the center of the ellipse 7 shown in FIG. 4 (B) coincides with the point Ow. The above-mentioned movement is possible by mounting the workpiece moving stage 1 having two or more moving axes on the main shaft 4.

As a processing method, in the case of a workable material which can be cut, a single crystal diamond cutting tool is used to obtain an axially asymmetric aspherical workpiece having a highly precise machined surface. By using this axially asymmetrical aspherical workpiece as a mold for injection molding, it is possible to produce a highly accurate axially asymmetrical aspherical optical element, for example, a plastic lens.

Further, in the case of a work material which is not suitable for cutting, by grinding with the rotary grindstone 13 shown in FIG. 2, it is possible to obtain an axially asymmetric aspherical workpiece having a highly accurate machined surface. By using this axially asymmetrical aspherical workpiece as a mold for injection molding, it is possible to produce a highly accurate axially asymmetrical aspherical optical element, for example, a plastic lens.

When the shape to be machined is far away from the spherical shape, the amount of movement of the workpiece 2 at the outer peripheral portion becomes large, so that the workpiece moving stage 1 synchronizes with the other moving axes of the processing machine. It may not be possible to move it, and the processing accuracy may drop. In such a case, the spindle 4 is
By lowering the rotation speed of, the moving speed of the workpiece moving stage 1 can be moderated and the processing accuracy can be improved.

In the case of the present invention, since it is necessary to synchronize the rotating shaft of the spindle 4 and the workpiece moving stage 1, the rotation speed of the spindle 4 is limited by the speed of the workpiece moving stage 1. When the workpiece moving stage 1 is not used, the number of rotations of the main shaft 4 can be increased, and therefore, the spherical shape and the axisymmetric aspherical shape which can be processed without using the workpiece moving stage 1 are close to the final shape. The processing time can be shortened by forming the processed surface of the shape and then performing the axially asymmetric aspherical surface processing using the workpiece moving stage 1.

Since the number of axes that need to be controlled is larger than in the case of ordinary axisymmetric aspherical surface machining, it is difficult to create a highly accurate shape with a single machining, but the shape of the machined surface is evaluated. Then, by reflecting the shape error and changing the movement trajectory of the processing tool and the workpiece 2, it is possible to perform the axially asymmetric aspherical surface processing having excellent shape accuracy. The present invention is not limited to the above embodiment. That is, various modifications can be made without departing from the gist of the present invention.

[0037]

As is apparent from the above description, according to the invention of claim 1 or 6, it is possible to perform highly accurate axial asymmetric aspherical surface machining.

Further, according to the invention of claim 2 or 3, it is possible to move the work piece in two or more axes on the main spindle and to move the work piece in synchronization with the other movement axes of the processing machine. By using a processing machine equipped with a stage, the workpiece can be positioned at the position necessary for axially asymmetrical aspherical machining with respect to the center of rotation of the spindle, thus achieving axially asymmetrical aspherical machining. be able to.

According to the fourth aspect of the present invention, by using a single crystal diamond tool as the tool, it is possible to perform highly accurate axial asymmetric aspherical surface processing.

According to the fifth aspect of the present invention, by using the rotary grindstone as the tool, it is possible to perform the axially asymmetric aspherical surface machining on the work material which is difficult to cut.

Further, according to the invention of claim 7, since the load on the workpiece moving stage can be reduced by suppressing the rotational speed of the main shaft at the outer peripheral portion, it is possible to perform highly accurate processing of the axially asymmetric aspherical surface. It can be carried out.

According to the invention of claim 8, a spherical surface which can be machined without using the workpiece moving stage or an axially symmetric aspherical surface is formed to form a shape close to a final axially asymmetrical aspherical shape, and thus a short time is obtained. Thus, it becomes possible to perform desired axially asymmetric aspherical surface processing.

According to the invention of claim 9, it is possible to manufacture a highly accurate axially asymmetric aspherical surface processed product. Further, by molding using the manufactured axially asymmetrical aspherical processed product, a highly accurate axially asymmetrical aspherical element can be manufactured.

[Brief description of drawings]

FIG. 1 is a perspective view showing an overall configuration of an axially asymmetric aspherical surface processing machine according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing an overall configuration of an axially asymmetric aspherical surface processing machine according to a second embodiment of the present invention.

FIG. 3 is a view showing an example of axially asymmetrical aspherical surface processing by the axially asymmetrical aspherical surface processing machine shown in FIG. 1;

FIG. 4A is a view of a cross section of an axially asymmetric aspherical surface and a tool taken along the XZ plane, and FIG. 4B is a view of a machining region viewed from the Z direction.

FIG. 5 is a diagram showing an elliptical shape to be processed.

FIG. 6 is a diagram showing a locus of a point Ow corresponding to an elliptical shape to be processed.

7 is an X of a processing point P when processing the ellipse of FIG.
It is a figure which shows the change of coordinates.

FIG. 8 is a diagram showing the states of a processing point Ow and a processing point P during processing.

FIG. 9 is a diagram showing an axially asymmetric aspherical surface processing method of a first conventional example.

FIG. 10 is a diagram showing an axially asymmetric aspherical surface processing method of a second conventional example.

[Explanation of symbols]

1 Workpiece movement stage 2 Processed products 3 processing tools 4 spindles 5 Spindle rotation axis 13 rotary whetstone 32 X-direction moving stage 33 Z-direction movement stage

Claims (9)

[Claims] 1. A processing machine for forming a machined surface by moving a tool relative to a machined work while rotating the machined work mounted on a rotatable spindle, and machining in synchronization with a machining position. An axis asymmetric non-axis characterized by comprising a workpiece moving means for moving the workpiece in a radial direction of the main axis on a plane perpendicular to the rotation axis, and a tool moving means for changing the tool position according to the machining position. Sphere processing machine. 2. The axis asymmetric aspherical surface processing machine according to claim 1, wherein a workpiece moving stage having two or more axes of movement attached to the spindle is used as the workpiece moving means. Characteristic axial asymmetric aspherical surface processing machine. 3. The axially asymmetric aspherical surface processing machine according to claim 2, wherein the workpiece moving stage is synchronized with a rotating shaft of the main shaft and a moving shaft of the tool moving means. Axially aspherical surface processing machine. 4. The axially asymmetric aspherical surface processing machine according to claim 1, wherein a single crystal diamond is used as the tool. 5. The axial asymmetric aspherical surface processing machine according to claim 1, wherein a rotary grindstone is used as the tool. 6. A machining method of forming a machining surface by moving a tool relative to a workpiece while rotating a workpiece mounted on a rotatable spindle, and machining in synchronization with a machining position. Axial asymmetric aspherical machining characterized by performing axial asymmetrical aspherical machining by moving an object in the radial direction of the main axis on a plane perpendicular to the rotation axis and changing the tool position according to the machining position. Law. 7. The axially asymmetric aspherical surface machining method according to claim 6, wherein the machining of the outer peripheral portion where the movement amount of the workpiece is large is performed at a lower rotational speed of the spindle than the machining of the inner peripheral portion. Axially asymmetric aspherical surface processing method. 8. The axially asymmetric aspherical surface processing method according to claim 6, wherein the workpiece is approximated to the axially asymmetrical aspherical surface before the axially asymmetrical aspherical surface processing is performed. An axially asymmetric aspherical surface processing method characterized by being processed into 9. An axially asymmetric aspherical surface processed product processed by the axially asymmetrical aspherical surface processing method according to claim 6.