JP2716317B2 - Cutting method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cutting a workpiece into a desired shape by controlling the attitude of a cutting tool mounted on a machine spindle of a machine tool.
A table movable in two axial directions, a machine spindle movable in a Z-axis direction orthogonal to the X and Y axes toward a work mounted on the table, and a cutting tool mounted on the machine spindle, At least two other axes different from the Y and Z axes (A
Axis, B-axis, or C-axis) using a machine tool having a rotary feed shaft capable of imparting a rotational displacement about a predetermined rotation of a hale bite-type cutting tool mounted on the machine spindle. The present invention relates to a method of cutting a processed shape having a cross-sectional shape different from a blade front shape into a processed portion of a work.

[0002]

2. Description of the Related Art A machine tool having three axes of X, Y, and Z axes and a C axis is mounted on a machine spindle of the machine tool, and a cross section of a machining shape to be obtained at a portion to be machined of a workpiece. By controlling the rotation of the C-axis via a machine spindle, a hale bite-shaped cutting tool having a blade front shape that matches the shape,
The cutting blade attitude of the cutting tool is changed according to the change in the relative movement locus between the cutting tool and the work so that the cross-sectional shape that matches the front shape of the blade is always transferred and cut to the processed part of the work. The cutting method described above is described in Japanese Patent Publication No. 63-54485 filed by the present applicant. More specifically, as shown in FIG.
A workpiece 1 installed on a machining table 4 movable in the axial direction; a cutting tool 2 mounted on a tool spindle 10 provided on a spindle head 9 movable in the Z axis direction so as to be capable of rotating and feeding the C axis; Is relatively moved in the three-dimensional directions of the X, Y, and Z axes, and the cutting tool 2 performs a cutting process. A C-axis that rotates around an axis passing through the center of the cutting edge of the hail tool, while controlling the movement trajectory of the center of the cutting edge of the hail cutting tool using three-dimensional feeds of X, Y, and Z axes. The work device 1 and the general-shaped helical tool 2 are relatively moved by controlling the rotation angle of the control tool, so that the movement trajectory of the cutting edge of the general-purpose helical tool matches the desired three-dimensional shape to be obtained. 12
The machining tool 3 is a cutting method in which the workpiece 1 is machined under the control of the machine tool 3.
Drive motors 5 and 6 for feeding X in the X and Y axis directions and a feed drive motor 8 for feeding a spindle head 9 in the Z axis direction via a feed mechanism 7 and a C axis rotation to the tool spindle 10 via the spindle head 9. And a C-axis drive motor 11 which is connected to the control device 12 to form a control mechanism.

[0003]

However, in the above-mentioned cutting method, the front face shape of the full-sized helical tool mounted on the machine spindle of the four-axis machine tool is directly changed to 1
It is characterized by the fact that the work to be machined is cut by a one-to-one shape transfer relationship. Therefore, the shape of the work to be machined into the work to be machined is completely unique due to the blade front shape of the full-sized hail bite. There is a problem that lacks diversity because there is a restriction that it is determined by In other words, when it is necessary to cut various different processing shapes on the work to be processed, each time the processing shape changes, select the corresponding overall shaped hae bite, replace it with the machine spindle of the machine tool, mount it, There are drawbacks in that it is necessary to perform cutting work, a large number of cutting tools need to be prepared in advance, and performing cutting work while exchanging tools is limited in terms of machining efficiency.

On the other hand, in the case of a machine tool, not only the conventional four-axis type machine tool shown in FIG. 6 but also a rotary feed shaft such as an A-axis or a B-axis in a direction orthogonal to the C-axis in addition to the C-axis described above. Machine tools having a system have been conventionally provided.

Accordingly, an object of the present invention is to use one cutting tool, in particular, one hale bite type cutting tool having a predetermined blade front shape, and to have a cross-sectional shape different from the blade front shape. It is an object of the present invention to provide a cutting method capable of cutting a processed shape of a processed portion of a work.

[0006]

SUMMARY OF THE INVENTION In view of the above-mentioned object, the present invention provides a cutting tool via a machine spindle around at least two axes in addition to a linear feed mechanism in X, Y and Z directions. When using a machine tool capable of controlling and imparting rotational displacement to a machine tool, a cutting tool having a hail bite-shaped predetermined blade front shape attached to the machine spindle of the machine tool is moved along a movement locus with a workpiece. By applying a displacement around the above two axes, a machining method having a cross-sectional shape different from the blade front shape can be obtained in a portion to be processed of a work.

That is, according to the present invention, a linear motion feed shaft capable of imparting relative displacement in the X, Y, and Z directions between a work mounted on a table and a cutting tool mounted on a machine spindle. And a cutting method for performing a cutting process on a workpiece by a machine tool having a rotary feed shaft capable of imparting rotational displacement about at least two of the X, Y, and Z axes. A mounted cutting tool having a predetermined blade front shape that has been preliminarily shaped is moved along a predetermined tool trajectory in the X, Y, and Z axes relative to a workpiece mounted on the table. The cutting tool mounted on the main spindle at the time of relative movement of the cutting tool, so that a predetermined cutting edge posture corresponding to one cross-sectional shape of a processing shape to be cut into the work portion of the work. Control the rotary feed axis By the feeding operation in the Z-axis direction of the machine spindle, the cutting tool is repeatedly subjected to a slight additional feed in the cutting direction while maintaining the predetermined cutting edge posture, thereby forming a processed shape having a cross-sectional shape different from the blade front shape. And a cutting method characterized by performing cutting.

[0008]

According to the above construction, the processing portion having a cross section different from the front shape of the blade is formed on the portion to be processed of the work by applying a rotational displacement of the cutting tool around two axes. Since the cutting process is performed, even if a single cutting tool is used, a processed shape having one cross-sectional shape different from the front shape of the cutting edge can be obtained on the work.

Hereinafter, the present invention will be described in more detail based on embodiments shown in the accompanying drawings.

[0010]

FIG. 1 is a perspective view showing an example of the configuration of a machine tool used in a cutting method according to the present invention, and FIG.
FIG. 3B is a side view of a hale bite type cutting tool and a cross-sectional view of a workpiece to be processed when the workpiece is processed with the front shape of the cutting edge. FIGS. 3A and 3B are C in the machine tool of FIG. FIG. 4 is a cross-sectional view showing a state in which a work shape having one cross-sectional shape different from the front shape of a cutting edge is cut into a workpiece by rotating and displacing a helical cutting tool in an axial direction;
(A) and (b) show that the work tool having a cross-sectional shape different from the front shape of the cutting blade was cut into a workpiece by rotating and displacing the hail bite type cutting tool in the A-axis direction in the machine tool of FIG. FIG. 5 (a) is a sectional view showing the state of the case,
FIG. 3B is a cross-sectional view illustrating that the surface roughness of the work surface of the workpiece is different due to the difference in the amount of rotational displacement of the cutting tool about two axes.

Referring to FIG. 1, there is shown an example of a machine tool that can be used to execute the cutting method of the present invention, which is a five-axis vertical machine tool. That is, the machine tool 20
Are mounted on the bed 22 and are orthogonal to each other in a horizontal plane.
There is a processing table 24 movable in the two Y-axis directions, and a workpiece W to be processed is mounted on the processing table 24. The feed movement of the processing table 24 in the X-axis direction and the Y-axis direction is performed via respective feed mechanisms provided in the bed 22.
This is performed using the drive motors Mx and My as drive sources.

On the other hand, the machine tool 20 has a ram 28 movable in the Z-axis direction orthogonal to the X-axis and the Y-axis above the column 26, and the ram 28 is connected to the main shaft via a rotating face plate 30. A head 32 is mounted, and the spindle head 32 has a machine spindle, ie, a spindle 34. The ram 28 performs a feed operation in the Z-axis direction using the drive motor Mz as a drive source, whereby the spindle head 32 and the spindle 34 are directed to the machining table 24 via the rotating face plate 30, or vice versa. The feed operation can be performed in a direction away from the camera. The spindle head 32 and the spindle 34 rotatably held by the spindle head 32 and the rotary face plate 30 can rotate the A-axis by using the drive motor Ma as a drive source.
The main shaft 34 is provided so as to be capable of C-axis rotation around the axis of the main shaft 34 by using a driving motor Mc mounted on the main shaft head 32 as a driving source. Thus, the cutting tool 4
By mounting 0, relative movement along the desired trajectory to the same cutting tool 40 with respect to the work W by feed movement in three axis directions of the X axis, Y axis, and Z axis, and cut feed toward the inside of the work. In addition, if necessary, the workpiece W attached to the processing table 24 can be cut using the rotational displacement of the C axis and the A axis. The above-described drive motors Mx, My, Mz and Ma, M
c is connected to a control device 38 composed of an NC device, and the operation is controlled in accordance with a command input from the control device 38.

The above-described five-axis vertical machine tool 20 has an X-axis, a Y-axis
In addition to the feed mechanism of the three axes orthogonal to the axis and the Z axis, there is a structure capable of rotating the spindle 34 and the cutting tool 40 mounted on the spindle 34 via the spindle head 32 along the C axis and the A axis. Needless to say, a six-axis vertical machine tool capable of imparting another rotational displacement of the B-axis as needed can be used in the embodiment of the present invention. Further, the present invention is not limited to the vertical machine tool, and it is also possible to use a horizontal machine tool in which the Z-axis constituting the feed axis of the main shaft is horizontally arranged.

Now, paying attention to the cutting tool 40,
The cutting tool 40 of the present invention is a hail bite type cutting tool that performs a cutting action in accordance with the principle of the hale machining, and FIG.
As shown in an example, a cutting blade 48 is fixed to a tool holding end in a lower region of the tool shank 42 by a fixing screw 46,
A slit 44 for forming an elastic deformation fulcrum capable of absorbing vibration caused by a cutting reaction force during a cutting operation is formed in a region above the cutting blade 48.
The cutting blade 48 has a blade front shape, that is, a shape as viewed in the direction of the arrow “F” in FIG. ,
By performing relative movement between the workpiece W and the surface of the portion to be processed, the workpiece W is cut into a processing shape having a certain correlation with the blade front shape. Now
Cutting blade 4 of hale bite type cutting tool 40 of FIG.
8, assuming that the blade front shape has a circular arc shape that forms a perfect circular partial arc, the cutting tool 4 is configured to transfer the arc-shaped blade front shape to the portion to be processed of the workpiece W as it is.
When the position of the 0 cutting blade 48 is controlled by the operation of the C-axis rotation feed means of the machine tool about the center line, the processing shape having the circular arc cross section as shown in FIG. It is cut and formed on the workpiece. As described above, only the C-axis rotation feed means of the machine tool is used to make the hale bite type cutting tool 4.
The position of the cutting blade 48 is controlled during the movement in the cutting movement direction so that the one-to-one processing shape with the blade front shape is always set to the workpiece W.
The method of cutting is only equivalent to the prior art of FIG. 6 described above.

However, according to the present invention, the blade front shape (in the present embodiment, by using the hale bite type cutting tool 40 and the two rotary feed means of the machine tool A and C axes). The workpiece W can be cut into a work shape having a certain correlation with the circular arc shape and a cross sectional shape different from the circular arc cross section as shown in FIG.

FIGS. 3 (a) and 3 (b) show a cutting blade 48 of a hale bite type cutting tool 40 having an arcuate blade front shape.
2A, the C-axis is rotated by a constant angle from the posture shown in FIG. 2A while being attached to the main shaft 34 by the C-axis rotation feed means using the drive motor Mc of the machine tool 20 as a drive source. In addition, the cutting tool 40 is moved along a three-dimensional movement trajectory of the X-axis, the Y-axis, and the Z-axis with respect to the portion to be processed of the workpiece W to maintain the rotational displacement at a certain angle. When the C-axis rotation feed means is controlled by the control device 38 to perform a cutting process, a processing shape having a cross section of a substantially semi-ellipse in which the major axis direction of the ellipse is the depth direction of the work is formed on the portion to be processed of the workpiece W. This shows a state where cutting and forming have been performed. In other words, the C-axis rotation feed means applies a rotational displacement at a predetermined angle in the clockwise direction in the direction indicated by the arrow C in FIG. In the case where the movement trajectory is not only a straight path but also a curved path, the given posture is always subjected to the cutting control by performing two controls including control for maintaining the same.

Here, the machining shape of the elliptical cross section is such that the cutting amount is gradually increased by the Z-axis feed mechanism of the machine tool 20 while the single hale bite-shaped cutting tool 40 is moved along a predetermined movement locus. Needless to say, a processed shape having an elliptical cross-sectional shape having a predetermined depth is obtained.

On the other hand, FIGS. 4 (a) and 4 (b) show that the hail bite cutting tool 40 is given a rotational displacement of a predetermined angle from the state of FIG. As shown in FIG. 4A, the cutting edge of the cutting blade 48 is laid down from the vertical position, and the hale bite-shaped cutting tool 40 is moved in the three-dimensional feed direction in this state. By maintaining the attitude of the cutting blade 48 by means of the C-axis rotation feed means, a processing shape having a substantially semi-ellipse with a minor axis of the ellipse in the depth direction of the workpiece and having a cross-sectional shape is obtained. . That is, in this example, the two rotary feed means, the A-axis rotary feed means and the C-axis rotary feed means, are controlled by the control device 38 to obtain a desired processed shape having an elliptical cross section.

From the above description based on the examples shown in FIGS. 3 and 4, the present invention provides a processing shape in which a shape different from the blade front shape of the cutting blade 48 of the hail bite type cutting tool 40 is set to one cross-sectional shape. It can be understood that these are cutting methods, but these processing shapes use a cross-sectional shape different from the front shape of the cutting edge by making use of at least two rotary feed means in the process of cutting the work. In the above description, the position of the cutting blade is obtained so that the workpiece W is cut, and the posture is maintained along the movement trajectory. It is also possible to apply a rotational displacement to the cutting blade 48 by making full use of the means or the C-axis rotating feed means to cut a plurality of different processing shapes on the processed portion of the work W, or to form the work W In the case of a mold, etc., the corner is narrow In the process of processing the surface in a curved surface and in the process of processing a relatively large area, the cutting process is performed while adjusting the cutting blade posture in the direction of the movement trajectory of the cutting tool 40 to various rotational displacement states. It is also possible.

Here, referring to FIG. 5 (a), for the example in which the cutting blade 48 of the hale bite-shaped cutting tool 40 has an arc-shaped blade front shape, the cutting blade posture of FIG. A case where the processing surface of the work W is repeatedly machined with the pick feed Pf1 while maintaining the pick feed Pf1 is shown. It can be understood that a rough machining surface portion having a high uncut height H1 is formed, while a curved surface with a small radius of curvature can be obtained at the corner Wa of the work W.

On the other hand, referring to FIG. 5B, in the case where the cutting blade 48 of the hale bite-shaped cutting tool 40 has an arc-shaped blade front shape, the cutting blade posture of FIG. 4A is maintained. Shows a case where the processing surface of the work W is repeatedly machined by the pick feed Pf2. At this time, if the pick surface Pf2 is simply maintained and machined on the work surface of a wide area region of the work W, the low uncut height is reduced. It is shown that a processed skin portion having H2 is formed. In this case, it can be understood that it is difficult to obtain a curved surface having a small radius of curvature at the corner Wa of the work W. That is, in this example, it is possible to improve the surface roughness of the processing surface, and when cutting the same processing area, the number of pick feeds can be reduced, that is, the processing efficiency is reduced as shown in FIG. ) Can be understood to be higher.

Referring to FIGS. 5A and 5B, in the course of performing the cutting using a single hale bite-shaped cutting tool 40, the state of the machining area of the work W is taken into consideration. However, it can be seen that the cutting process can be appropriately advanced. Although the present invention has been described with reference to the embodiments, it is needless to say that the cutting method according to the present invention is not limited to the case of using the illustrated 5-axis vertical machine tool. Further, it can be understood that, according to the A-axis and C-axis rotation feed means in the illustrated example, a rotational displacement about the B axis can be given to the cutting tool by a combined rotational displacement of both.

[0023]

As can be understood from the above description, according to the present invention, in addition to the feed mechanism in the X, Y, and Z-axis directions, the rotational displacement is applied to the cutting tool via at least two axes via the machine spindle. When using a machine tool that can be controlled and assigned, when a cutting tool having a hale bite-shaped predetermined blade front shape mounted on a machine spindle of the machine tool is moved along a movement locus with the work, By giving a rotational displacement about one axis, a cutting method is obtained in which a processing shape having a cross-sectional shape different from the blade front shape can be cut on the processed portion of the work, and therefore, one cutting Diversification of cutting performance, improvement of machining efficiency, and good surface roughness of the work surface in that various machining shapes with a certain correlation of the blade front shape can be machined using tools. Obtain various effects such as securing degree Theft is possible.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a configuration of a machine tool used in a cutting method according to the present invention.

FIG. 2A is a side view of a hail bite type cutting tool. FIG. 3B is a cross-sectional view of a workpiece to be processed when the workpiece is processed with the cutting edge front shape of the hale bite type cutting tool.

FIG. 3A is a partial side view showing a state in which a hale bite type cutting tool is rotationally displaced in the C-axis direction in the machine tool of FIG. FIG. 4B is a cross-sectional view illustrating a state in which a workpiece having a cross-sectional shape different from the front shape of the cutting blade in the posture of FIG.

FIG. 4A is a partial side view showing a state in which a hale bite type cutting tool is rotationally displaced in the A-axis direction in the machine tool of FIG. FIG. 4B is a cross-sectional view illustrating a state in which a work having a cross-sectional shape different from the front shape of the cutting edge cut by the cutting tool having the same posture is cut into the work.

FIGS. 5A and 5B are cross-sectional views illustrating that the surface roughness of a work surface of a workpiece is different due to a difference in a rotational displacement amount of a cutting tool around two axes.

FIG. 6 is a perspective view illustrating a configuration of a machine tool used for performing a conventional cutting method.

[Explanation of symbols]

 20 ... machine tool 22 ... base 24 ... machining table 32 ... spindle head 34 ... spindle 38 ... control device 40 ... cutting tool 42 ... shank 48 ... cutting blade Ma ... drive motor Mc ... drive motor Mx ... drive motor My ... drive motor Mz … Drive motor W… Work

Claims (1)

(57) [Claims] A linear motion feed shaft capable of imparting relative displacement in the X, Y, and Z axis directions between a workpiece mounted on a table and a cutting tool mounted on a machine spindle;
In a cutting method for performing a cutting process on a workpiece by a machine tool having a rotary feed shaft capable of imparting a rotational displacement about at least two of the Y and Z axes, the workpiece is mounted on the main spindle and shaped in advance. Moving the cutting tool having a predetermined blade front shape relative to a workpiece attached to the table along a predetermined tool trajectory in three axial directions of X, Y, and Z. The rotary feed shaft is controlled so that the cutting tool mounted on the main spindle of the machine at the time of the relative movement has a predetermined cutting edge posture corresponding to one cross-sectional shape of a machining shape to be machined on the portion to be machined of the work. By the feed operation in the Z-axis direction of the machine spindle, the cutting tool repeatedly repeats the slightly increasing feed in the cutting direction with the predetermined cutting edge posture, thereby forming a processing shape having a cross-sectional shape different from the blade front shape. The A cutting method characterized by cutting into a workpiece.