JP2002126901A - Cutting method, cutting device, and mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting work capable of machining even a curved surface, having a small radius of curvature, with excellent surface roughness in a short time. SOLUTION: A cutting tool 2 is caused to effect movement in the cutting force direction and the thrust force direction on a work by two or more direct acting actuators 10a and 10b, the tip of the cutting tool 2 is caused to effect rotational movement, and the cutting tool is scanned in the direction approximately orthogonal to the cutting direction to effect a cutting work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical element or a mold for machining an optical element or a metal mold thereof, which has a small radius of curvature and has an unfixed free-form surface. The present invention relates to a technique for shortening a processing time while obtaining.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG.
When the longitudinal direction is the generatrix direction (X direction) and the transverse direction is the sagittal direction (Y direction), a mold of an optical component such as a toric shape having a different radius of curvature between the generatrix direction and the sagittal direction is cut. In the case, the diamond tip 102a and the shank 10
A cutting tool 102 made of 2b is attached to a tool holder 103, and the cutting tool is rotated by a main shaft 104. At this time, the tip radius of the diamond tip 102a must be smaller than the radius of curvature of the sagittal wire of the workpiece, and the turning radius R1 of the cutting tool needs to be smaller than the radius of curvature R2 of the generatrix of the workpiece. In this state, the cutting tool and the workpiece are relatively moved in the sagittal direction, so that one minute line is fly-cut, then moved in the generatrix direction at a feed pitch P, and this is repeated. , Cut the entire surface.
The processing time is determined by the moving speed in the sagittal direction determined by the required surface roughness and the radius of the tip of the diamond tip, and the turning radius R1.
Is determined by the feed pitch P determined from

[0003] In recent years, optical components have been required to have small and complicated free-form surfaces with the miniaturization and high performance of products using the optical components. For this reason, the specifications required for a high-precision optical mold have a small curvature in terms of shape, and the required surface roughness is required to be further improved.

[0004] In response to such a demand, in the fly-cut method, the turning radius of the cutting tool must be smaller than the smallest radius of curvature of the workpiece, and a cutting tool for fixing the cutting tool to the spindle is required. The diameter of the protruding portion 103a needs to be smaller than the turning diameter, and further thinner in order to avoid interference with the workpiece. In order to obtain the same surface roughness by reducing the turning radius,
It is necessary to reduce the feed pitch P in the generatrix direction.

Further, as one means for improving the processing accuracy, a vibration cutting method for forcibly vibrating a cutting tool has been proposed (Japanese Patent Application Laid-Open Nos. 7-68401 and 10-166204). In turning or drilling, this method reduces the cutting resistance by vibrating the cutting tool, improves machining accuracy, and extends tool life. It is not possible at present to machine curved surfaces.

[0006]

However, when the diameter of the bite holder is reduced, there is a problem that the shape accuracy and the surface roughness are reduced due to a reduction in bite holding rigidity and occurrence of chatter vibration due to cutting resistance. Further, as the feed pitch P becomes smaller, there is a problem that the processing time per unit area becomes longer.

Further, the current vibration cutting method is an assisting method, and it is impossible at present to machine a free-form surface such as a toric shape.

[0008] The technique disclosed in Japanese Patent Application Laid-Open No. 7-68401 is a vibration cutting method generally called ("precision processing vibration cutting": contents described in Jikkyo Shuppan Co., Ltd.). Since it is intended to be applied to turning and milling to improve the cutting quality, it can be applied to mirror machining of curved surfaces based on optical relationships by the movement of the cutting tool due to vibration. ,
The following problems occur:

A fly-cutting method generally used in conventional mirror-finish processing performs reciprocating processing in order to reduce a return time and a processing time when a cutting tool and a workpiece are relatively scanned and moved. I was However, JP-A-7-68
In the technology disclosed in Japanese Patent Publication No. 401, when reciprocating machining is performed to relatively move the cutting tool and the work material in the cutting direction, it is necessary to use upcut and downcut on the outward path and the return path. However, there is a drawback that it is not suitable for reciprocating processing because the damage of the surface and the state of the processed surface are different.

[0010] Regarding the damage to the cutting tool due to the up-cut and down-cut, in the case of the down-cut, as shown in FIG. 8, the force in the back force direction (also referred to as the direction of the vertical force of the cutting resistance, the cutting direction). The speed is faster than the speed in the cutting direction, and the angle of entry of the tool is close to a right angle, so the damage to the cutting tool is large (movement of the tool trajectory at the position of the cutting tool in the figure). As shown in FIG. 9, when the tool enters from the direction in which cutting is proceeding, the speed in the cutting direction is faster than the speed in the back force direction, and the approach angle of the tool can be reduced (see FIG. 9). The movement of the tool trajectory at the middle cutting tool position), and the damage to the cutting tool can be reduced. Regarding the characteristics of the machined surface, it can be said that the up cut and the down cut are different for the same reason.

In the technique disclosed in Japanese Patent Application Laid-Open No. 7-68401, the cutting tool is separated from the chip and the finished surface within a period having a negative speed component. As shown in (1), since the cutting tool returns before leaving the chips and the workpiece, the chips cannot be cut, and the chips tend to be continuous. This continuous swarf can damage the finished surface. Also, considering that the chip is separated from the chip and the work material when having a speed in the negative cutting direction, the cut amount is larger than the half amplitude in the back force direction. Down cutting is not desirable because the operation of cutting the work material occurs on the flank of the cutting tool like a part.

In view of the fact that reciprocating cutting cannot be performed,
There is a problem that the processing time per unit area becomes longer.

Accordingly, the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a cutting method and apparatus capable of processing a curved surface having a small radius of curvature with good surface roughness and in a short time. It is to provide.

[0014]

Means for Solving the Problems The above-mentioned problems are solved,
In order to achieve the object, a cutting method according to the present invention is directed to a cutting method in which a cutting tool is moved relative to a workpiece by a main component direction and a back component force by two or more linear actuators moving in directions substantially perpendicular to each other. The cutting tool is rotated by moving the tip of the cutting tool in a direction substantially perpendicular to the cutting direction.

Further, in the cutting method according to the present invention, the linear motion actuator may be set at 100 Hz to 100 Hz.
It is characterized by being driven at a frequency of 0 Hz.

Further, in the cutting method according to the present invention, only the vibration amplitude of the cutting tool in the main component direction is changed in accordance with the curvature of the processing surface of the workpiece in the main component direction. It is characterized in that the vibration amplitude in the force direction is made constant.

Further, in the cutting method according to the present invention, the change of the vibration amplitude is performed by changing a command waveform to the linear motion actuator, and the change of the command waveform is performed by the cutting tool by the cutting tool. It is characterized in that it is performed when it is not in contact with the processed surface of the object.

In the cutting method according to the present invention, the command waveform applied to the linear actuator that drives the cutting tool in the direction of the back force is a substantially trapezoidal wave, and the rising and falling portions of the trapezoidal wave are , Characterized by using a curve by a higher-order function.

In the cutting method according to the present invention, the command waveform applied to the direct acting actuator for driving the cutting tool in the main component force direction is a constant command value of a trapezoidal wave which is a command waveform in the back force direction. The cutting tool is characterized in that the moving speed of the cutting tool in the main component direction is maximized in the portion.

In the cutting method according to the present invention, a command waveform applied to a linear motion actuator for driving the cutting tool in a main component direction is a substantially rectangular wave, and a rising portion or a falling portion of the rectangular wave is determined. , Which is characterized by matching the value with a constant command value portion of a trapezoidal wave which is a command waveform in the back force direction.

The cutting apparatus according to the present invention comprises a main body for supporting the cutting tool, a first linear motion actuator for vibrating the main body in a main component direction of the cutting tool, A second linear actuator for vibrating the main body in the direction of the back force of the cutting tool, and a second linear actuator arranged at a position away from a portion of the main body that supports the cutting tool; A first leaf spring movably supporting only the back component direction, and a first leaf spring disposed at a position close to a portion of the main body portion supporting the cutting tool, the main body portion having a main component force direction and a back component force; And a second leaf spring that is supported so as to be movable only in the direction.

Further, in the cutting apparatus according to the present invention, the first and second linear actuators are preferably
It is characterized by being driven at a frequency of 0 Hz to 1000 Hz.

Further, a die according to the present invention is characterized in that it is processed by the above-mentioned cutting method.

Further, a mold according to the present invention is characterized in that it is processed by the above-mentioned cutting device.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic view of a processing apparatus according to an embodiment of the present invention.

In FIG. 1, the processing device includes a cutting device having a four-axis synchronous stage and a cutting unit 1 for moving a cutting tool. The cutting unit 1 includes a cutting tool (cutting tool) 2 and two linear actuator units 3a, 3
b and the main frame 4. The cutting unit 1 is fixed to a rotary positioning stage 5 of a four-axis synchronous cutting device, and the rotary positioning stage 5 is disposed on a stage 6 that moves in the Z direction. Reference numeral 7 denotes a work (workpiece), 8 denotes a jig for fixing the work, and 9 denotes a stage that moves in the X and Y directions. Work 7
Is fixed to the XY stage 9 by a jig 8. In the present embodiment, the work 7 is, for example, a mold for molding an optical element.

Next, the processing operation of this embodiment will be described with reference to FIG.

The cutting tool 2 is rotated by two linear actuators 3a and 3b arranged in directions orthogonal to each other (the principle of rotating the cutting tool 2 by the linear actuator will be described later). Is X
The scanning movement is performed in the Y direction by the Y stage 9, and the processing proceeds. When the scanning in the Y direction is completed, the step moves in the X direction, and the scanning movement in the Y direction is performed again. By repeating this, the entire surface of the work is processed. The Z stage 6 controls the position of the cutting tool 2 in the Z direction in synchronization with the scanning in the Y direction according to the shape of the free-form surface to be formed. In addition, according to the inclination (curvature) of the free-form surface, normal rotation is tracked by the rotation positioning stage 5 so that the back force direction of the cutting tool 2 always faces the normal direction of the free-form surface. By this processing operation, free-form mirror processing can be performed.

Next, the details of the cutting unit 1, which is a characteristic part of the present embodiment, will be described with reference to FIGS.

FIG. 2 is a sectional view of the cutting unit. FIG.
Linear actuator units 3a, 3
b includes actuators 10a and 10b and cooling units 11a and 11b, respectively.
Extends and contracts in the Z direction, and the actuator 10b is arranged in a direction that expands and contracts in the X direction. In the present embodiment, giant magnetostrictive elements are used for the actuators 10a and 10b. Further, in order to minimize the influence of thermal displacement due to the heat generated by the actuator and to achieve thermal stability in a short time, the cooling unit 11a,
The actuator is cooled by 11b.

The cutting tool 2 is an ultra-precision diamond cutting tool having a diamond tip 2b fixed to the tip of a shank 2a. The cutting tool 2 is fixed to a cutting tool holder 12, and the cutting tool holder 12 is fixed to a movable portion 13. The linear actuators 10a and 10b are connected to the movable part 13 via elastic hinges 14a and 14b. The elastic hinge 14a has a single-stage hinge portion.
b is a two-stage hinge portion.

The movable part 13 is composed of leaf springs 15a, 15b.
To the main frame 4. Leaf spring 15
a is a leaf spring having a cross shape as shown in FIG. 3, which is rigid in the X and Y directions and soft in the Z direction. The position in the Z direction is arranged so as to substantially coincide with the center of the elastic hinge 14a. FIG. 4 shows the leaf spring 15b.
Are leaf springs that are rigid in the Y direction and soft in the X and Z directions. With the configuration of the actuator, the leaf spring, and the elastic hinge, the movable portion 13 moves in the Z direction by the expansion and contraction of the linear actuator 10a, and the center of the cross shape of the leaf spring 15a is rotated by the expansion and contraction of the linear actuator 10b. The circular motion of arrow A is performed. The movement of the linear actuator 10b is enlarged by the ratio of the lengths L1 and L2 shown in FIG. The linear actuators 10a, 1
Due to the movement of 0b, the tip of the cutting tool 2 makes a rotational movement in the XZ plane. By appropriately changing the shape and arrangement of the leaf spring, it is possible to increase the rigidity of components other than the moving direction of the tip of the cutting tool and to increase the stroke in the X direction.

Next, the linear motion actuators 10a and 10b
With reference to FIGS. 5 and 6, what kind of movement of the tip of the cutting tool 2 is performed and what kind of command waveform is desirable for performing the cutting process will be described.

FIG. 5A shows an actuator 1 in the Z direction.
It is the figure which showed the command waveform to 0a. The horizontal axis shows the time of one cycle of the command waveform, and the vertical axis shows the command value (amplitude) in the Z direction. FIG. 5B shows an actuator 1 in the X direction.
FIG. 5 is a diagram showing a command waveform to 0b.
Same as (a). By synchronizing and moving the command waveforms of FIGS. 5 (a) and 5 (b),
The trajectory (c) moves. In the machining of this method, the portion formed as the cutting surface of the work is a portion processed by the Z-direction actuator 10a in the vicinity of the maximum command value, and in FIG. Become.

FIG. 5D is an enlarged view of the locus of the maximum command value portion serving as the cutting surface. Among them, A is the trajectory of the present embodiment, and B is the turning radius of the fly-cut method of 20 mm.
The trajectory, C is the turning radius of the fly-cut method 50m
It is a locus at the time of m. The surface roughness of the cutting surface is shown in FIG.
Is determined by the length of Z1 shown in FIG. For example, if aiming at a theoretical surface roughness of 20 nm, the displacement in the Z direction is 4.98 μm.
It is necessary to transfer the part of the locus between 5.00 μm and 5.00 μm to the work. For this purpose, the feed pitch in the X direction needs to be ± 32 μm or less for the locus A and ± 28 μm or less for the locus B. The trajectory C can be set to ± 50 μm or more. From this, it can be understood that, according to the fly-cut method, in order to obtain the same surface roughness, the feed pitch in the X-direction greatly changes depending on the turning radius. It can be seen that a feed pitch in the X direction equivalent to a radius of about 20 mm can be achieved.

FIG. 6 shows that the command waveform to the Z-direction actuator in the method of the present embodiment is the same as that of FIG. 5, and the locus of the locus when the maximum command value (amplitude) of the command value waveform in the X direction is changed to ± 30 μm. FIG. (A), (b),
(C) and (d) are of the same type as FIG. FIG.
In (d), the trajectory A is the trajectory of the present embodiment, the trajectory B is a trajectory with a turning radius of 20 mm in the fly-cut system, and the trajectory C is a trajectory with a turning radius of 10 mm in the fly-cut system. Thus, the trajectory shown in FIG.
It turns out that it is equivalent to between 0 and 20 mm.

5 and 6, the turning radius parameter in the fly-cut method can be changed only by changing the command waveform (amplitude) in the X direction, which is a feature of the present embodiment. In the conventional fly-cut method, a single workpiece was machined with a constant turning radius.However, the function to change the pseudo turning radius by changing the command waveform to this actuator has made it possible to process the workpiece in this method. The point enables machining with a turning radius that is optimal for the radius of curvature of the workpiece shape at the machining point. Thereby, the feed pitch in the X direction at each processing point can be set to the maximum size that satisfies the theoretical surface roughness,
Processing time can be greatly reduced.

It is desirable that the chips when performing mirror finishing are cut every time the cutting tool makes one rotation, and the cutting amount of the cutting tool in the back force direction is the amplitude of the back force direction. It must be smaller than 1/2.

Also, by the above-described tool trajectory (turning radius) changing method which changes only the command waveform to the actuator in the X direction, the command value waveform to the actuator in the cutting direction directly related to the cutting amount can be made constant. In addition, the driving conditions of the actuator can be made constant, and the thermal fluctuation thereof can be suppressed.

FIG. 12 is a schematic diagram of the trajectory when the amplitudes in the main component direction (the direction of the horizontal component force of the cutting force) and the back component direction (the direction of the vertical component force of the cutting force) are changed. is there. Here, the vertical axis is the back component direction, and the horizontal axis is the main component direction.
(A) shows a case where both amplitudes are changed, and (b) shows a case where only the main component force direction is changed. The portion that is finally transferred to the workpiece is the lowest point portion. (A) shows that the curvature of the lowest point portion does not change, while (b) shows the locus curvature of the lowest point portion. Is changing. Also, since the back force direction is the cutting direction of the cutting tool and is the direction that most affects the shape accuracy, the actuator in the back force direction can be driven under certain conditions to maintain thermal stability. Desirable in terms of accuracy. From these two points, it can be seen that when changing the trajectory, it is desirable to change only the amplitude in the main component force direction.

Here, it is desirable to change the command locus when there is no workpiece below the cutting tool according to the processing data. Thus, even if disturbance vibration occurs in the cutting tool due to the change in the command waveform, the workpiece is not affected. Also, if it is possible to calculate the command waveform from the memory that stores the command waveform data or the function formula that represents the command waveform, change the command waveform when the cutting tool is not in contact with the workpiece. Can be.

Next, the pattern of the command waveform will be described.

First, since the command waveform in the cutting direction (Z direction) affects the surface roughness, it is preferable that the command waveform be as close as possible to the radius of curvature of the processing point. However, since it is necessary to correspond to the shape of the workpiece with both the irregularities, it is easy to think that the command value to the actuator is constant in the command waveform portion forming the processing surface. Therefore, it is desirable that the command waveform to the Z-direction actuator is based on a trapezoidal wave. However, since high-frequency driving is required in this processing method, a large change in acceleration / deceleration is likely to cause disturbance-like movement of the cutting tool, and the surface roughness may be degraded. For this reason,
As shown in FIGS. 5 and 6, the rising and falling of the command waveform to the Z-direction actuator is preferably a smooth command waveform. Specifically, it is a curve using a quintic function.

Next, a command waveform in the feed direction (X direction) will be described.

The command waveform in the feed direction can control the cutting speed in addition to the pseudo turning radius changing function as described above. Even with the command value of the SIN waveform, the speed changes according to the time within one cycle. For this reason, the Z-direction actuator is used as the processing surface (the part forming the mirror surface of the workpiece).
In the command waveform to the X-direction actuator corresponding to the position where is processed, it is desirable that the speed component has the fastest waveform within one cycle. In the present embodiment, the COS waveform is used as the command waveform to the X-direction actuator. However, by using a rectangular waveform instead, it is possible to increase the cutting speed even at the same driving frequency. According to the concept of the waveform in the X direction, the cutting speed can be increased even at the same driving frequency, and the cutting characteristics can be improved.

Next, the actual machining procedure will be described with reference to FIG. 13. In a state where the cutting tool 2 is always subjected to elliptical vibration,
The workpiece 1 and the cutting tool 2 are moved relative to each other at a point a1 on an extended line that applies an optical relationship to the generatrix direction (X direction) end b1 of the workpiece 1 and move in the sagittal direction (Y direction). Processing is performed (the cutting tool and the workpiece are relatively moved so that movement in the Y direction is mainly performed), and processing for one line is performed.
The actual tool path is L1 in FIG. 13, and a1 → b1 → c
1 → d1 → e1, and since the direction of the back force of the cutting tool coincides with the normal direction of the processing surface and changes in the Z direction, in order to satisfy a tool trajectory that follows the shape. Performs processing of one line while moving in the X and Z directions. After that, the normal angle is moved by the rotation positioning stage 5 that moves the feed pitch to move from the point e1 to e2 in the generatrix direction and the rotation index of the cutting tool, and performs the machining feed in the sagittal direction (e2 → d2 → c2 → b2 → a
2). By repeating this operation, the entire surface of the workpiece 1 is processed, and as a result, a target processed surface is obtained. By such processing, it is possible to obtain a high shape accuracy of the order of 0.1 μm, which is equivalent to the device movement accuracy.

The operation of changing the trajectory of the vibration of the cutting tool in such a machining method will be described with reference to FIG.
At the positions a and e, the trajectory of the vibration is changed. This is because the vibration command value is given as the amplitude (the amount of extension of the actuator) with respect to the time within one cycle, so that one cycle is 50 times.
The data string divided as described above is necessary, and the time for exchanging the data cannot be completed within the time obtained by dividing one cycle, and discontinuity occurs in the command value. This is an operation necessary to avoid this discontinuity. For example, 500
If one cycle is divided into 50 when driving at Hz, there is a time problem since the data string must be changed within 40 μs. Therefore, it is desirable to change the trajectory of the vibration when there is no workpiece below the cutting tool.

When a curved surface based on an optical system is mirror-finished, an error from a command value of the position of the cutting edge must be 10 nm or less. This is because surface roughness of about 30 nm is required for high-precision mirror finishing, and 30 nm is required due to the reproducibility of cutting tools, equipment vibration, theoretical roughness generated from tool trajectories, etc.
When an error is allocated, 10 nm or less is required.

In order to satisfy 10 nm, it is necessary to minimize the overshoot of the vibration source with respect to the command value of the actuator. In particular, when the actuator in the direction of the back force is moved by a trapezoidal wave, the position command changes abruptly at the lowest point, causing an overshoot and a problem of excessive cutting. To avoid this, 5
It is necessary to reduce the overshoot by using a command value using the following function or the like. Further, in order to further reduce the overshoot, as shown in FIG. 14, the command value is approximated to a triangular wave, the flat portion in one cycle is reduced, the acceleration / deceleration time is increased, and the robot is moved slowly. I do. However, if the flat portion is made smaller, the portion that can be used for processing becomes shorter, so that the feed pitch cannot be increased. Therefore, as shown in FIG. 15, by making the trajectory waveform in the feed direction a rectangular wave, the feed pitch can be increased.

As described above, according to the above embodiment, the direct acting actuator allows the cutting tool to apply a main component force (horizontal component force of cutting resistance) and a back component force (cutting force) to the workpiece. While moving (vibrating) in the direction
By moving (scanning) in the direction orthogonal to the cutting direction, it is possible to process a workpiece having a small radius of curvature with high accuracy.

Further, by changing only the command waveform in the feed direction, machining can be performed with a turning radius (tool trajectory) optimal for the radius of curvature of the workpiece, and the machining time can be reduced.

Further, the driving condition of the actuator in the cutting direction can be made constant by this method of changing the command waveform, and the influence of heat on the processed shape can be eliminated.

Further, by selecting a command waveform in the cutting direction or a command waveform in the feed direction, disturbance vibration during high-speed driving can be reduced, and the cutting speed can be increased.

As a result, it is possible to increase the ability to cope with the shape, achieve high-precision processing, and reduce the processing time in the mirror finishing of the mold.

[0056]

As described above, according to the present invention,
Even a curved surface having a small radius of curvature can be processed with good surface roughness and in a short time.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a processing apparatus according to an embodiment of the present invention.

FIG. 2 is a detailed view of a cutting unit of the processing apparatus shown in FIG.

FIG. 3 is a view showing a shape of a leaf spring used in the cutting unit.

FIG. 4 is a view showing a shape of a leaf spring used in the cutting unit.

FIG. 5 is a diagram showing a command locus and a tool locus used in one embodiment.

FIG. 6 is a diagram illustrating another example of a command trajectory and a tool trajectory used in an embodiment.

FIG. 7 is a schematic view showing a conventional fly cut cutting method.

FIG. 8 is a diagram illustrating a locus of a cutting tool in a case of a down cut.

FIG. 9 is a diagram illustrating a locus of a cutting tool in the case of an upcut.

FIG. 10 is a diagram illustrating a locus of a cutting tool in the case of an upcut.

FIG. 11 is a diagram showing a locus of a cutting tool in the case of a down cut.

FIG. 12 is a schematic diagram showing the trajectory of the cutting tool when the amplitudes in the main component force direction and the back component direction are changed.

FIG. 13 is a diagram showing a specific example of cutting.

FIG. 14 is a diagram showing a command value in the back force direction applied to the actuator.

FIG. 15 is a diagram showing a command value in a main component force direction applied to an actuator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cutting unit 2 Tool 2a Shank 2b Diamond chip 3a, 3b Actuator unit 4 Main frame 5 Rotational positioning stage 6 Z stage 7 Work (workpiece) 8 Work fixing jig 9 XY stage 10a, 10b Actuator 11a, 11b Cooling jacket 12 Tool holder 13 Movable part 14a, 14b Elastic hinge 15a, 15b Leaf spring 101 Workpiece (work) 102 Cutting tool (bite) 102a Diamond tip 102b Shank 103 Tool holder 104 Tool spindle

Claims (11)

[Claims] 1. A cutting tool is moved in a main component force direction and a back component force direction with respect to a workpiece by two or more linear motion actuators moving in directions substantially orthogonal to each other, and the tip of the cutting tool is moved. The cutting method is performed by rotating the cutting tool and scanning the cutting tool in a direction substantially orthogonal to the cutting direction. 2. The linear actuator according to claim 1, wherein
The cutting method according to claim 1, wherein the driving is performed at a frequency of 1000 Hz. 3. The vibration amplitude of the cutting tool in the main component direction is changed according to the curvature of the processing surface of the workpiece in the main component direction to keep the vibration amplitude in the back component direction constant. The cutting method according to claim 1, wherein the cutting is performed. 4. The method according to claim 1, wherein the changing of the vibration amplitude is performed by changing a command waveform to the linear actuator, and the changing of the command waveform is performed when the cutting tool is not in contact with the processing surface of the workpiece. The cutting method according to claim 3, wherein the cutting method is performed occasionally. 5. A command waveform applied to a linear motion actuator that drives the cutting tool in the direction of a back force is a substantially trapezoidal wave.
2. The cutting method according to claim 1, wherein a curve based on a higher-order function is used for a rising portion and a falling portion of the trapezoidal wave. 6. A command waveform applied to a linear motion actuator that drives the cutting tool in a main component direction is a constant component value of a trapezoidal wave which is a command waveform in a back component direction. The cutting method according to claim 5, wherein the moving speed in the direction is set to be maximum. 7. A command waveform applied to a linear motion actuator that drives the cutting tool in a main component force direction is a substantially rectangular wave,
7. The cutting method according to claim 6, wherein a rising portion or a falling portion of the rectangular wave is made to coincide with a portion of a constant command value of a trapezoidal wave which is a command waveform in the back force direction. 8. A main body for supporting the cutting tool, a first linear actuator for vibrating the main body in a main component direction of the cutting tool, and A second direct-acting actuator for vibrating in the component force direction; and a second linear motion actuator disposed at a position away from a portion of the main body portion supporting the cutting tool, so that the main body portion can be moved only in the back force direction. A first leaf spring to be supported, a first leaf spring being disposed at a position close to a portion of the main body portion supporting the cutting tool, and supporting the main body portion so as to be movable only in a main component force direction and a back component force direction. A cutting device comprising: a second leaf spring. 9. The cutting apparatus according to claim 8, wherein the first and second linear actuators are driven at a frequency of 100 Hz to 1000 Hz. 10. A mold processed by the cutting method according to any one of claims 1 to 7. 11. A die machined by the cutting apparatus according to claim 8 or 9.