JP2001162428A - Free-form surface machining method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a free-form surface machining method that precisely machines a free-form surface on a workpiece while detecting the relative position between the tool and the workpiece and correcting the positions of both of them. SOLUTION: A working machine 10 comprises an X-axis, a Y-axis and a Z-axis table controllable or movable in the respective axis directions. A workpiece 12 is positioned, for example, on the Z-axis table 11. The working machine 10 is so constructed that a cutting tool 15 is detachably mounted on a wheel 14 coupled to a rotary shaft 13 and is driven or rotated by a drive motor 16. The Z-axis table 11 is equipped with a position measuring arm 19 having a position measuring mark M at the tip face, and that face of the drive motor 16 which opens on the workpiece 12 carries a position measuring sensor 20. Before cutting work by relative displacement between the cutting tool 15 and workpiece 12, the working machine 10 uses the position measuring sensor 20 to measure the distance d between the position measuring mark M and position measuring sensor 20, and controls the position of the cutting tool 15 or workpiece 12 and the relative distance between both of them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for processing a free-form surface, and more particularly, to a method for forming a free-form surface on a work with high accuracy while detecting a relative position between a tool and a work and correcting both positions. The present invention relates to a free-form surface processing method for processing.

[0002]

2. Description of the Related Art In machining a three-dimensional free-form surface shape,
Generally, as shown in FIG. 5, while rotating a tool 1 such as an arc-shaped cutting tool or a grinding tool having a predetermined rotation radius, the rotation center of the tool 1 is relatively moved with respect to the workpiece 2. , Creating a curved surface shape.

More specifically, the tool 1 is detachably attached to a wheel 3 of a three-axis control processing machine (not shown), and rotates at a predetermined rotation speed via a rotation shaft 4 fixed to the wheel 3. It is driven to rotate about the shaft 4. The processing machine includes an X-axis table, a Y-axis table, and a Z-axis table (not shown), and each table is moved in each of the X, Y, and Z-axis directions by a control unit (not shown) based on numerical control data. Controlled. The workpiece 2 is, for example, removably fixed on a Y-axis table, and the processing machine controls the movement of the X-axis table, the Y-axis table, and the Z-axis table in each axis direction, so that the tool 1 and the workpiece are controlled. A free-form surface is machined on the workpiece 2 by the tool 1 by controlling the relative position of the workpiece 2 to three axes.

In this case, the rotation center of the tool 1 is moved in the order of A → B → C → D → E as shown by an arrow in FIG.
As shown in FIG. 7, a part of the area L1 of the workpiece 2 is processed, and when the processing of the area L1 is completed, the position of the tool 1 is then moved by a predetermined pitch in the Y direction, and the area L2 is similarly processed. I do. By repeating this operation, the workpiece 2 is processed into a curved surface.

When a curved surface is machined on the workpiece 2 by repeating such an operation, the area L1 is machined on the YZ plane of the workpiece 2 as shown in FIG. In order to machine the workpiece, the tool 1 is moved in the Y direction by a predetermined pitch, and the tool 1 is positioned with respect to the workpiece 2 in the Z direction to perform machining.

That is, in the conventional free-form surface machining method, the position of the tool 1 and the workpiece 2 is controlled by the set value of the machine without measuring the distance between the tool 1 and the workpiece 2, and the workpiece 1 is processed by the tool 1. 2 is processed.

[0007]

However, in such a conventional free-form surface machining method, the distance between the tool 1 and the workpiece 2 is not measured during the machining, and the tool 1 and the workpiece 1 are not measured by the set value of the machine. Since the workpiece 2 is processed by the tool 1 by controlling the position of the workpiece 2, even if the tool 1 is moved to the same Z coordinate in the machine coordinates, as shown in FIG. 2 distance dL1 between reference plane S and tool 1 and region L
In some cases, the processed shape was out of order because the distance dL2 at No. 2 did not match.

That is, as shown in FIG. 9, a measuring point Q is set on a workpiece 2 fixed on a table of a processing machine, and a distance measuring sensor 6 is mounted on a processing machine 5 on which a tool 1 (not shown) is mounted. The tool 1 is moved on the XZ plane as shown by the arrow in FIG. 9 to measure the distance of the distance measuring sensor 6 in the Z direction at the measuring point Q to the measuring point Q.
Examining the reproducibility of the positional relationship between the processing machine and the workpiece, FIG.
The measurement results are as shown in FIG.

[0009] As can be seen from FIG. 10, it can be seen that the distance fluctuates at the set value of the machine even though the tool 1 is moved to the same position. In FIG. 10,
The horizontal axis indicates the number of movements of the tool 1, and the vertical axis indicates the tool 1
The distance (nm) between the distance measurement sensor 6 and the measurement point Q is shown.

That is, even if the tool 1 is moved to the same position on the setting of the processing machine, the error of the processing machine, the processing machine and the work 2
There is a problem in that the distance between the tool 1 and the workpiece 2 changes due to thermal fluctuations and the like.

Therefore, the invention according to claim 1 controls the relative position between the workpiece and the center of rotation of the tool, and when the workpiece is processed into a free-form surface shape by the rotating tool, the tool and the workpiece are separated. By detecting the relative position and correcting the misalignment between the tool and the workpiece based on the detection result, the misalignment of the relative position between the workpiece and the tool is kept to a minimum and high-precision machining is performed. It is an object of the present invention to provide a free-form surface processing method that can be performed.

According to a second aspect of the present invention, when the tool once separates from the processing surface of the workpiece and comes into contact with the processing surface again, the relative position between the tool and the workpiece is changed before the contact with the processing surface. By detecting the position and correcting the positional deviation between the tool and the workpiece based on the detection result, each time the workpiece is processed by the tool, the relative positional deviation between the workpiece and the tool is corrected before the processing. It is an object of the present invention to provide a free-form surface processing method capable of performing processing with higher precision while keeping the minimum.

According to a third aspect of the present invention, the position of the tool is adjusted based on the result of detection of the relative position between the tool and the workpiece to correct the displacement between the tool and the workpiece.
It is an object of the present invention to provide a free-form surface machining method capable of performing high-precision machining while keeping the displacement of a relative position between a workpiece and a tool at a low cost and at a minimum.

According to a fourth aspect of the present invention, the position of the workpiece is adjusted based on the result of detection of the relative position between the tool and the workpiece, and the displacement between the tool and the workpiece is corrected.
It is an object of the present invention to provide a free-form surface processing method capable of performing high-precision processing while keeping the relative positional deviation between a workpiece and a tool at a minimum.

According to a fifth aspect of the present invention, the position of a workpiece is adjusted using a predetermined actuator capable of controlling the position with a finer accuracy than the finest movement control value capable of adjusting the position of the tool. By correcting the misalignment with the workpiece, it is difficult to change the set value of the machining machine during machining, even if the relative displacement between the workpiece and the tool is corrected, Adjusting the position of the workpiece with finer accuracy than the minimum setting value of the processing machine, maintaining the relative positional deviation between the workpiece and the tool to a minimum, and performing more accurate processing An object of the present invention is to provide a free-form surface processing method that can be used.

[0016] According to a sixth aspect of the present invention, a position measuring point is provided near a workpiece, and a relative position between the tool and the workpiece is detected with reference to the position measuring point, whereby the workpiece and the tool are connected to each other. Provided is a free-form surface machining method capable of detecting a relative position of a workpiece with higher accuracy, appropriately maintaining a relative position shift between a workpiece and a tool to a minimum, and performing more accurate machining. It is an object.

According to a seventh aspect of the present invention, the relative position between the workpiece and the tool is detected with higher accuracy by arranging the position measurement points on a predetermined measurement object disposed near the workpiece. In addition, it is an object of the present invention to provide a free-form surface processing method capable of more appropriately maintaining a relative displacement between a workpiece and a tool to a minimum and performing more accurate processing.

According to the present invention, the object to be measured is formed of a material having a coefficient of thermal expansion close to that of the object to be processed, so that the relative position between the object and the tool can be improved while avoiding thermal fluctuation of the measuring point. Provided is a free-form surface processing method capable of detecting with higher precision, holding the displacement of the relative position between the workpiece and the tool more appropriately to a minimum, and performing higher-precision processing. The purpose is.

According to a ninth aspect of the present invention, a predetermined distance measuring sensor is provided near the tool, and the distance between the tool and the workpiece is measured by measuring the distance from the position measuring point with the distance measuring sensor. By detecting, the relative position between the workpiece and the tool is detected with even higher accuracy, and the positional deviation of the relative position between the workpiece and the tool is more appropriately kept to a minimum, so that more accurate machining can be performed. It is an object of the present invention to provide a free-form surface processing method that can be performed.

[0020]

According to a first aspect of the present invention, there is provided a free-form surface machining method for controlling a relative position between a workpiece and a center of rotation of a tool while rotating a tool having a predetermined rotation radius. A free-form surface processing method for processing the workpiece into a free-form surface shape with the rotating tool, wherein during the processing, a relative position between the tool and the workpiece is detected, and based on the detection result, The above object is achieved by correcting a displacement between the tool and the workpiece.

According to the above configuration, the relative position between the tool and the workpiece is detected by controlling the relative position between the workpiece and the center of rotation of the tool to process the workpiece into a free-form surface with the rotating tool. Then, since the displacement between the tool and the workpiece is corrected based on the detection result, the displacement of the relative position between the workpiece and the tool can be kept to a minimum, and high-precision machining can be performed. It can be carried out.

In this case, for example, as described in claim 2, in the machining, when the tool once comes away from the machining surface of the workpiece and contacts the machining surface again, Before the contact, the relative position between the tool and the workpiece may be detected, and the displacement between the tool and the workpiece may be corrected based on the detection result.

According to the above arrangement, when the tool once comes off the processing surface of the workpiece and contacts the processing surface again,
Before contacting the processing surface, the relative position between the tool and the workpiece is detected, and the positional deviation between the tool and the workpiece is corrected based on the detection result. In each case, the positional deviation of the relative position between the workpiece and the tool can be kept to a minimum before the processing, and more accurate processing can be performed.

Further, for example, as described in claim 3, the position of the tool may be adjusted based on the detection result to correct the positional deviation between the tool and the workpiece.

According to the above configuration, the position of the tool is adjusted based on the result of detection of the relative position between the tool and the workpiece, and the positional deviation between the tool and the workpiece is corrected. The displacement of the relative position can be kept to a minimum at low cost, and high-precision machining can be performed.

Further, for example, as described in claim 4, the position of the workpiece may be adjusted based on the detection result to correct the displacement between the tool and the workpiece.

According to the above arrangement, the position of the workpiece is adjusted based on the result of detection of the relative position between the tool and the workpiece.
Since the displacement between the tool and the workpiece is corrected, the displacement of the relative position between the workpiece and the tool can be kept to a minimum, and high-precision machining can be performed.

Further, for example, as described in claim 5, the position of the workpiece is determined using a predetermined actuator capable of controlling the position with a finer precision than the finest movement control value capable of adjusting the position of the tool. An adjustment may be made to correct the misalignment between the tool and the workpiece.

According to the above arrangement, the position of the workpiece is adjusted using the predetermined actuator capable of controlling the position with a finer precision than the finest movement control value capable of adjusting the position of the tool. Since it is possible to correct the misalignment between the workpiece and the tool, even if it is difficult to change the set value of the The position of the workpiece is adjusted with finer accuracy than the minimum setting value of the machine, and the positional deviation of the relative position between the workpiece and the tool can be kept to a minimum, and more precise processing is performed be able to.

Further, for example, as set forth in claim 6, a position measuring point is arranged near the workpiece, and a relative position between the tool and the workpiece is detected with reference to the position measuring point. You may.

According to the above arrangement, the position measuring point is arranged near the workpiece and the relative position between the tool and the workpiece is detected based on the position measuring point. By detecting the relative position with higher precision, the positional deviation of the relative position between the workpiece and the tool can be appropriately kept to a minimum, and more precise processing can be performed.

Further, for example, as described in claim 7, the position measuring point may be arranged on a predetermined measuring object arranged near the workpiece.

According to the above configuration, the position measuring point is arranged on the predetermined object arranged near the workpiece.
By detecting the relative position of the workpiece and the tool with higher precision, the positional deviation of the relative position between the workpiece and the tool can be more appropriately kept to a minimum, and more accurate processing can be performed. it can.

Further, for example, the object to be measured may be formed of a material having a thermal expansion coefficient close to that of the workpiece.

According to the above configuration, since the workpiece is formed of a material having a coefficient of thermal expansion close to that of the workpiece, the relative position between the workpiece and the tool can be further reduced by avoiding thermal fluctuation of the measuring point. By detecting with high precision, the positional deviation of the relative position between the workpiece and the tool can be more appropriately kept to a minimum, and more precise processing can be performed.

Further, for example, a predetermined distance measuring sensor is disposed near the tool,
The distance measurement sensor may measure a distance from the position measurement point to detect a relative position between the tool and the workpiece.

According to the above arrangement, a predetermined distance measuring sensor is arranged near the tool, and the distance measuring sensor measures the distance between the position measuring point and the relative position between the tool and the workpiece. Since the relative position between the workpiece and the tool can be detected with higher accuracy, the positional deviation of the relative position between the workpiece and the tool can be more appropriately kept to a minimum, and a higher precision Processing can be performed.

[0038]

Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. It should be noted that the embodiments described below are preferred embodiments of the present invention, and therefore, various technically preferable limitations are added. However, the scope of the present invention is not limited to the following description. The embodiments are not limited to these embodiments unless otherwise specified.

FIGS. 1 to 4 are views showing an embodiment of a free-form surface machining method according to the present invention. FIG. 1 is a diagram showing a free-form surface machining method according to an embodiment of the present invention. FIG. 2 is a partially enlarged front view of the processing machine 10 of the XYZ three-axis control applied, and FIG. 2 is a partial perspective view of the processing machine 10 of FIG.

In FIGS. 1 and 2, the three-axis control machine 10 includes an X-axis table, a Y-axis table, and a Z-axis table. In FIGS. 12 are installed. Processing machine 10
Controls the movement of each table including the Z-axis table 11 in the directions of the X, Y, and Z axes by a control unit (not shown) based on numerical control data.

The processing machine 10 has a wheel 14
Is fixed, and a cutting tool (tool) 1
5 is detachably attached. The rotating shaft 13 is connected to a motor shaft of a driving motor 16 and is driven to rotate at a predetermined rotation speed by the driving motor 16. The drive motor 16 is attached to the arm 18 of the movable table 17 movable in the X and Z directions so as to be movable in the Y direction.
The movement of the movement table 17 and the movement in the Y direction with respect to the arm 18 enable the movement in the X, Y, and Z axes. Therefore, the cutting tool 15 is
The movement of the drive motor 16 in each of the X, Y, and Z axes by the movement of the arm 18 and the movement in the Y direction with respect to the arm 18 causes movement control in the X, Y, and Z axes.

The processing machine 10 controls the movement of the X-axis table, the Y-axis table and the Z-axis table 11 in the respective axial directions, and also controls the movement of the cutting tool 15 in the respective X, Y and Z-axis directions. By doing so, the cutting tool 15 and the workpiece 12
Is controlled on three axes, and a free-form surface is machined on the workpiece 12 by the cutting tool 15.

The cutting tool 15 is formed in an arc shape, and is driven to rotate about a rotating shaft 13 to cut the workpiece 12 as shown by an arrow in FIG.

The processing machine 10 has a Z
A position measuring arm (object to be measured) 19 is provided on the axis table 11, and a position measuring mark (position measuring point) M is provided on a tip end surface of the position measuring arm 19 on the cutting tool 15 side. The position measurement arm 19 provided with the position measurement mark M is formed of a material having a similar thermal expansion coefficient to that of the workpiece 12, and is disposed near the workpiece 12.

On the other hand, near the cutting tool 15 of the processing machine 10,
Specifically, on the surface of the drive motor 16 on the workpiece 12 side,
As shown in FIG. 1, a position measurement sensor (distance measurement sensor) 20 is attached, and the position measurement sensor 20 is attached.
For example, a capacitance type displacement sensor is used.

Next, the operation of the present embodiment will be described. The free-form surface machining method using the three-axis control machine 10 according to the present embodiment includes a position measurement sensor 20 attached to the cutting tool 15 and a position measurement mark M attached to the workpiece 12.
Is characterized in that the distance between the cutting tool 15 and the workpiece 12 is measured to control the relative position between the cutting tool 15 and the workpiece 12 with high accuracy.

That is, in the free-form surface machining, the machining machine 10 relatively disposes the arc-shaped cutting tool 15 and the workpiece 12 in the order of A → B → C → D → E as in FIG. Move. That is, the processing machine 10 performs the cutting by relatively moving the cutting tool 15 and the workpiece 12 in the longitudinal direction (X direction), and then relatively moves in the Z direction to separate the cutting tool 15 and the workpiece 12, The cutting tool 15 and the workpiece 12 are moved to the cutting position by relatively moving in the X direction, returning to the cutting start position in the X direction, moving relatively by a predetermined pitch in the Y direction, and moving again in the Z direction. Then, the next cutting process is performed.

However, as described above, if position control is performed with machine set values without simply measuring the distance between the cutting tool 15 and the workpiece 12, the error of the machine 10 and the machine 1
0 and the thermal fluctuation of the workpiece 12, etc.
The distance between the workpiece 12 and the workpiece 12 changes.

Therefore, the processing machine 10 according to the present embodiment, first, moves the cutting tool 15 and the workpiece 12 relative to each other before performing the cutting process, and determines the initial position where the position measurement mark M is provided. Position measurement mark M at position (position A in FIG. 8)
The distance d between the position measurement sensor 20 and the position measurement sensor 20 is measured by the position measurement sensor 20, and the machine coordinates P (Xp, Yp, Zp) of the processing machine 10 at the time of performing the position measurement are obtained and controlled (not shown). Store in the memory of the unit

Next, the processing machine 10 relatively moves the cutting tool 15 and the workpiece 12 in the order of A → B → C → D → E and cuts the workpiece 12 with the cutting tool 15. 15 is moved to the coordinate position of P by the value of the machine coordinate, and the distance d between the position measurement mark M and the position measurement sensor 20 is measured again by the position measurement sensor 20, and the measurement distance at this time is d. '.

In this case, the relative positions of the cutting tool 15 and the workpiece 12 are shifted before and after the cutting, and the difference between the first measured distance d and the measured distance d ′ measured after the cutting is changed. δ occurs, that is, d′−d
= Δ (| δ |> 0), the processing machine 10
Only the relative position between the cutting tool 15 and the workpiece 12 is corrected and controlled, and the next cutting is performed in the same manner as described above.

The processing machine 10 controls the correction of the relative position between the cutting tool 15 and the workpiece 12 by moving the cutting tool 15 with respect to the workpiece 12 by the difference δ, as shown in FIG. However, as shown in FIG. 4, the workpiece 12 may be moved relative to the cutting tool 15 by the difference δ to correct the position.
3 and 4, when the difference δ is positive (δ>
0), but when the difference δ is negative (δ <0),
The position is corrected by moving the cutting tool 15 or the workpiece 12 in the direction opposite to the direction of the arrow shown in FIG. 3 or FIG.

When correcting the relative position between the cutting tool 15 and the workpiece 12, if the level at which the position of the processing machine 10 can be set is coarser than the resolution of the position measuring sensor 20, the processing machine 10 The position of the cutting tool 15 or the workpiece 12 is corrected so that the position difference δ is minimized.

When the relative position between the cutting tool 15 and the workpiece 12 is corrected by adjusting the position of the workpiece 12, as shown in FIG. 4, the finest position adjustment of the cutting tool 15 is possible. The position adjustment of the workpiece may be performed by using the actuator 30 capable of position accuracy with a finer accuracy than the movement control value.

As described above, the processing machine 10 of the present embodiment
Controls the relative position between the workpiece 12 and the center of rotation of the cutting tool 15 to form the workpiece 12 into a free-form surface with the rotating cutting tool 15.
2, and the positional deviation between the cutting tool 15 and the workpiece 12 is corrected based on the detection result.

Accordingly, the relative displacement between the workpiece 12 and the cutting tool 15 can be kept to a minimum.
High-precision processing can be performed.

Further, when the cutting tool 15 is once separated from the machined surface of the workpiece 12 and comes into contact with the machined surface again when the cutting tool 15 A relative position between the cutting tool 15 and the workpiece 12 is detected, and based on the detection result, the cutting tool 15 and the workpiece 12 are detected.
Has been corrected.

Therefore, each time the workpiece 12 is machined by the cutting tool 15, the relative positional deviation between the workpiece 12 and the cutting tool 15 can be kept to a minimum before the machining.
Higher precision processing can be performed.

Further, the position of the cutting tool 15 or the workpiece 12 is adjusted based on the detection result of the relative position between the cutting tool 15 and the workpiece 12, and the positional deviation between the cutting tool 15 and the workpiece 12 is corrected. ing.

Accordingly, the relative displacement between the workpiece 12 and the cutting tool 15 can be kept to a minimum at low cost, and high-precision machining can be performed.

Further, as shown in FIG. 4, the position of the workpiece 12 is adjusted by using an actuator 30 capable of adjusting the position with a finer accuracy than the finest movement control value capable of adjusting the position of the cutting tool 15. By adjusting the position of the workpiece 12,
When the displacement between the cutting tool 15 and the workpiece 12 is corrected,
Even in the case of the processing machine 10 in which it is difficult to change the setting value of the processing machine 10 during the processing, the positional deviation of the relative position between the workpiece 12 and the cutting tool 15 is corrected, and the minimum setting value of the processing machine 10 is corrected. By adjusting the position of the workpiece 12 with finer accuracy than
The positional deviation of the relative position between the workpiece 12 and the cutting tool 15 can be kept to a minimum, and more precise processing can be performed.

Further, in the processing machine 10 of the present embodiment, a position measuring mark M, which is a position measuring point, is arranged on a position measuring arm 19 which is a measuring object arranged near the workpiece 12.
The relative position between the cutting tool 15 and the workpiece 12 is detected based on the position measurement mark M.

Therefore, the relative position between the workpiece 12 and the cutting tool 15 can be detected with higher precision, and the positional deviation of the relative position between the workpiece 12 and the cutting tool 15 can be appropriately kept to a minimum. , More precise processing can be performed.

Further, in the processing machine 10 of the present embodiment, the position measuring arm 19 which is the object to be measured is formed of a material having a thermal expansion coefficient close to that of the object 12 to be processed.

Therefore, the relative position between the workpiece 12 and the cutting tool 15 is detected with higher accuracy while avoiding the thermal fluctuation of the position measurement mark M, and the relative position between the workpiece 12 and the cutting tool 15 is detected. The positional deviation can be more appropriately kept to a minimum, and processing with higher accuracy can be performed.

Further, in the processing machine 10 of the present embodiment, a predetermined distance measuring sensor 20 is arranged near the cutting tool 15 and the distance measuring sensor 20 measures the distance to the position measuring mark M. Thus, the relative position between the cutting tool 15 and the workpiece 12 is detected.

Therefore, the relative position between the workpiece 12 and the cutting tool 15 is detected with higher accuracy, and the positional deviation of the relative position between the workpiece 12 and the cutting tool 15 is more appropriately kept to a minimum. And more accurate processing can be performed.

Although the invention made by the inventor has been specifically described based on the preferred embodiments, the invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the invention. It goes without saying that it is possible.

For example, in the above embodiment, the capacitance type displacement sensor is used as the position measuring sensor 20 for measuring the relative distance between the cutting tool 15 and the workpiece 12. Is not limited to the capacitance type displacement sensor, but the cutting tool 15 and the workpiece 12
If it can measure the relative distance with the required accuracy,
Anything may be used.

[0070]

According to the free-form surface machining method according to the first aspect of the present invention, the relative position between the workpiece and the center of rotation of the tool is controlled so that the workpiece can be machined into a free-form surface shape by the rotating tool. , The relative position between the tool and the workpiece is detected, and the displacement between the tool and the workpiece is corrected based on the detection result. It can be held and high-precision processing can be performed.

According to the free-form surface machining method of the present invention, when the tool once comes off the machined surface of the workpiece and contacts the machined surface again, Since the relative position between the tool and the workpiece is detected, and the positional deviation between the tool and the workpiece is corrected based on the detection result, the relative position between the workpiece and the tool is changed each time the workpiece is machined. The positional displacement can be kept to a minimum before the processing, and more accurate processing can be performed.

According to the free-form surface machining method of the third aspect, the position of the tool is adjusted based on the result of detection of the relative position between the tool and the workpiece, and the positional deviation between the tool and the workpiece is corrected. As a result, the displacement of the relative position between the workpiece and the tool can be kept to a minimum at low cost, and high-precision machining can be performed.

According to the free-form surface machining method of the present invention, the position of the workpiece is adjusted based on the result of detection of the relative position between the tool and the workpiece, and the positional deviation between the tool and the workpiece is determined. Since the correction is performed, the displacement of the relative position between the workpiece and the tool can be kept to a minimum, and high-precision machining can be performed.

According to the free-form surface machining method of the present invention, the position of the workpiece is determined by using a predetermined actuator capable of controlling the position with a finer precision than the finest movement control value capable of adjusting the position of the tool. Since the adjustment is performed to correct the misalignment between the tool and the workpiece, even if it is difficult to change the set value of the processing machine during machining, the relative position between the workpiece and the tool can be adjusted. It is possible to correct misalignment and adjust the position of the workpiece with a finer precision than the minimum setting value of the processing machine, to further minimize the positional deviation of the relative position between the workpiece and the tool. In addition, it is possible to perform processing with higher accuracy.

According to the sixth aspect of the present invention, a position measuring point is provided near a workpiece, and a relative position between the tool and the workpiece is detected based on the position measuring point. Since the relative position between the workpiece and the tool can be detected with higher precision, the positional deviation between the relative position between the workpiece and the tool can be appropriately kept to a minimum, and more accurate processing can be performed. be able to.

According to the free-form surface machining method of the present invention, since the position measurement points are arranged on the predetermined object arranged near the object, the position of the object and the tool can be reduced. By detecting the relative position with higher accuracy, it is possible to more appropriately hold the positional deviation of the relative position between the workpiece and the tool to a minimum,
Higher precision processing can be performed.

According to the method for processing a free-form surface of the present invention, since the object to be measured is formed of a material having a coefficient of thermal expansion close to that of the object to be processed, thermal fluctuation of the measuring point is avoided while avoiding thermal fluctuation of the measuring point. Detecting the relative position between the tool and the tool with higher accuracy, the position of the relative position between the workpiece and the tool can be more appropriately kept to a minimum, and performing higher-precision machining. Can be.

According to the free-form surface machining method of the ninth aspect, a predetermined distance measuring sensor is provided near the tool,
Measure the distance to the position measurement point with the distance measurement sensor,
Since the relative position between the tool and the workpiece is detected, the relative position between the workpiece and the tool is detected with higher accuracy, and the positional deviation of the relative position between the workpiece and the tool is more appropriately minimized. , And more accurate processing can be performed.

[Brief description of the drawings]

FIG. 1 is a partially enlarged front view of a three-axis control processing machine to which an embodiment of a free-form surface processing method according to the present invention is applied.

FIG. 2 is a partially enlarged perspective view of the processing machine of FIG.

FIG. 3 is an enlarged front view of a state in which the position of the cutting tool and the workpiece of the processing machine of FIG. 1 is corrected by moving the cutting tool.

FIG. 4 is an enlarged front view of a state in which the positions of the cutting tool and the workpiece of the processing machine of FIG. 1 are corrected by moving the workpiece.

FIG. 5 is an enlarged perspective view of a cutting tool and a workpiece of a conventional processing machine.

FIG. 6 is a diagram illustrating a movement locus of a cutting tool of the processing machine in FIG. 5;

FIG. 7 is a perspective view showing a cutting area of a workpiece by the cutting tool of FIG. 5;

FIG. 8 is a side cross-sectional view showing a cutting area of the cut workpiece of FIG. 7;

9 is a plan view of a main part of the conventional processing machine in FIG. 5 in a state where reproducibility of a relative position between a cutting tool and a workpiece is measured.

FIG. 10 is a graph showing the measurement results of the relative positions of the cutting tool and the workpiece in FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Processing machine 11 Z-axis table 12 Workpiece 13 Rotation axis 14 Wheel 15 Cutting tool 16 Drive motor 17 Moving table 18 Arm 19 Position measuring arm 20 Position measuring sensor 30 Actuator M Position measuring mark

Claims (9)

[Claims] 1. A method of controlling a relative position between a workpiece and a center of rotation of a tool while rotating a tool having a predetermined radius of rotation, and processing the workpiece into a free-form surface by the rotating tool. A curved surface processing method, wherein during the processing, a relative position between the tool and the workpiece is detected, and a positional deviation between the tool and the workpiece is corrected based on the detection result. Free curved surface processing method. 2. In the machining, when the tool once contacts the machining surface after leaving the machining surface of the workpiece, the tool and the workpiece are contacted with each other before contacting the machining surface. 2. The free-form surface machining method according to claim 1, wherein a relative position of the tool is detected, and a positional shift between the tool and the workpiece is corrected based on the detection result. 3. The free-form surface machining according to claim 1, wherein the position of the tool is adjusted based on the detection result to correct a positional deviation between the tool and the workpiece. Method. 4. The free-form surface according to claim 1, wherein the position of the workpiece is adjusted based on the detection result to correct the positional deviation between the tool and the workpiece. Processing method. 5. The tool and the workpiece by performing position adjustment of the workpiece using a predetermined actuator capable of controlling the position with a finer precision than the finest movement control value capable of adjusting the position of the tool. 5. The method for processing a free-form surface according to claim 4, wherein the positional deviation from the position is corrected. 6. A position measuring point is provided near said workpiece,
The free-form surface machining method according to claim 1, wherein a relative position between the tool and the workpiece is detected based on the position measurement point. 7. The free-form surface machining method according to claim 6, wherein the position measurement points are arranged on a predetermined object arranged near the workpiece. 8. The free-form surface machining method according to claim 7, wherein said workpiece is made of a material having a thermal expansion coefficient close to that of said workpiece. 9. A predetermined distance measuring sensor is disposed near the tool, and the distance measuring sensor measures a distance from the position measuring point to detect a relative position between the tool and the workpiece. The free-form surface processing method according to claim 6, wherein: