JPH06126520A - Cutting method - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a cutting method for improving the working efficiency and accuracy in finishing cutting by hail cutting after rough cutting when processing a workpiece. [Structure] When performing a cutting process with a cutting tool 30 held by a hail processing holder 10, the same cutting tool 30 is used.
The cutting tool 34 is formed into a desired specific shape, and a cutting machine in which the tool spindle 8 is capable of cutting action rotation and C-axis rotary feed is used. 30 is mounted, the workpiece W is rotated by the rotation of the tool spindle 8 while leaving a predetermined machining allowance, and then the feed cutting action of the cutting tool 30 is performed along a machining trajectory according to the target machining shape of the workpiece W. It was applied to remove the residual machining allowance, and the single cutting tool 30 was used for consistent cutting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting method for cutting various kinds of works such as mold works into a predetermined working shape, and more particularly, to a high-speed cutting rotation of a tool spindle and its rotation around its axis. Using a processing machine that can perform both low-speed C-axis feed operation, the tool spindle of the processing machine has a tool holder, that is, a slit that allows elastic deformation in accordance with cutting resistance in the cutting process. Install a bite-shaped cutting tool with a cutting blade of a specific shape through the tool holder that has been cut,
By giving both effects of rotary cutting by the cutting rotation of the tool spindle and shaving by the feeding motion along the machining path according to the desired machining shape to this cutting tool, highly accurate work cutting The present invention relates to a cutting method that can be efficiently performed.

[0002]

2. Description of the Related Art Generally, in a cutting process for manufacturing a die, a workpiece, which is a processing material, is rough-cut to a desired processing shape by using a milling system rotary cutting tool such as an end mill in advance, and unnecessary material parts are removed. After rough cutting, the tool spindle of the processing machine is mounted on the tool spindle through the tool holder, and the tool is controlled by the C-axis rotary feed of the tool spindle (the cutting edge of the tool is set in the normal direction to the machining path). It refers to rotation control around one axis that controls the posture to face)
A method is adopted in which the finishing process is gradually performed by advancing the cutting along a machining locus corresponding to a desired machining shape by the feed control including.

In the latter finish cutting with the hail bite, the cutting amount of the cutting tool is advanced to the cutting direction in a cutting direction with a minute cutting amount of several microns to several tens of microns, and the cutting acting on the cutting blade is performed. Since the resistance is buffered by utilizing the elastic deformation function of the hail bite holder, it is possible to prevent the cutting edge from biting into the workpiece and roughening the machining surface, thus smoothing the workpiece. It has an advantage that a desired processed shape having a various processed surface can be formed.

[0004]

However, in the step of rough cutting with a rotary cutting tool such as an end mill when cutting a desired shape of a work such as a die by the above-described cutting method, the cutting amount, In order to increase the cutting speed as much as possible to improve the cutting efficiency, the rotary tool for rough cutting used has high cutting efficiency. In particular, when the roughing allowance is large, a rotary cutting tool having a large tool diameter is used. When a rotary tool having such a large tool diameter is used, for example, in the wall surface area of the work close to the machining shape, a large corrugated trace remains as a rotary cutting trace of the rotary cutting tool, and a corner (corner) In such cases, since the diameter of the rotary cutting is large with respect to the corner curvature of the desired machining shape, the residual machining allowance tends to increase. Therefore, the cutting allowance remaining after the rough cutting process by a rotary cutting tool such as an end mill is targeted according to the condition of the work part of the work, for example, whether it is a smooth surface, a corner or a special shape part. A non-uniform cutting allowance having large irregularities with respect to the desired processing shape remains.

Therefore, in the finishing cutting process for removing such a non-uniform residual cutting allowance, the cutting edge of the hail bite is cut in the process of advancing along a predetermined machining locus to obtain a desired target machining shape. The margin varies greatly depending on the position of the machining locus. Therefore, it is difficult to give a certain amount of cutting to the cutting edge of the hail bit, and inevitably, the machining area of the workpiece with a large amount of cutting allowance is repeatedly cut with a small cutting amount of the hail bit. Then
A method is adopted in which the machining allowance is gradually reduced to match the machining area with a relatively small remaining machining allowance, and then the final cutting is performed with a hail bite. For this reason, there is a problem that air cutting increases, and a long time is required for cutting each work.

On the other hand, in the course of rough cutting, the rotary cutting tool such as an end mill is changed from a rough cutting tool having a relatively large diameter to a tool having a relatively small diameter in order to reduce the residual machining allowance at the corner of the work. However, there is also a method of rough cutting, but with this, complicated setup work such as tool exchange is involved, and again, it is not possible to avoid a reduction in machining efficiency.

Accordingly, a main object of the present invention is to eliminate the above-mentioned problems of the conventional cutting method. Another object of the present invention is to improve the cutting efficiency by using the same hail bite type cutting tool in the process of performing the finishing process after rough cutting with the hail bite type cutting tool in the cutting process of the work. It is intended to provide a cutting method that can be achieved.

[0008]

According to the present invention, when the work is carried out by a hail bite type cutting tool, the shape of the cutting tool is specified, and the tool spindle has a high speed cutting rotation and a low speed C. Using a processing machine capable of axis rotary feed, equip the tool spindle with a hail bite type cutting tool, and control and give a feed cutting action along a machining trajectory according to the target machining shape of the workpiece. A cutting rotation is applied to the hail bite type cutting tool from the tool spindle, and the cutting allowance of the work is sufficiently reduced by the rotating cutting action of the cutting edge of the hail bite type cutting tool, thereby improving the efficiency of finish cutting by the feed cutting action. It is intended to.

That is, according to the present invention, a cutting tool held by a hail processing tool holder mounted on a tool spindle of a processing machine capable of C-axis rotary feed around the axis of the tool spindle with cutting rotation. A cutting method in which a rotary cutting action and a shaving action by feeding in a predetermined trajectory direction are sequentially applied to consistently cut a work with a single cutting tool, wherein the cutting tool includes an axis of the tool spindle. It is formed so as to include a cutting blade extending in a plane and only on one side of the shaft center, and the rotary cutting action is imparted to the cutting tool by the rotation of the tool spindle, so that the work is predetermined. A step of rotary cutting leaving a predetermined machining allowance for the machining shape, and finishing cutting for removing the machining allowance by giving only a feed along a trajectory corresponding to the predetermined machining shape to the cutting tool. Process and , At least with the cutting method is provided.

[0010]

According to the above-described cutting method, when a desired processing shape is cut on a work such as a die processing material,
First, a rotary cutting action is applied to a single cutting tool to advance cutting until a predetermined remaining cutting allowance is reached, and then the remaining cutting allowance is cut and removed by feeding along the cutting locus of the cutting tool. As a result, the cutting efficiency can be improved by rotating the cutting tool, and since a single cutting tool is used consistently, it is possible to avoid troubles such as tool changes and improve the cutting efficiency. It will be possible. Hereinafter, the present invention will be described in more detail with reference to the embodiments shown in the accompanying drawings.

[0011]

1 is a front view showing a state in which a cutting tool used for carrying out a cutting method according to the present invention is mounted on a tool spindle of a processing machine via a tool holder, and FIG.
2 is a side view including a partial cross section viewed from the line 2, FIG. 3 is an enlarged partial view for explaining the shape condition of the cutting blade portion of the cutting tool used for performing the cutting method of the present invention, and FIG. 4 is a corner portion of the work. FIG. 5 is a schematic view for explaining the action of the cutting method according to the present invention in the process of cutting a workpiece, and FIG.

In performing the cutting method according to the present invention, the processing machine used must satisfy the following conditions. In other words, the tool spindle is capable of performing a rotary cutting action by attaching a rotary cutting tool to the rotary cutting tool and applying a normal high-speed rotation to the rotary cutting tool. It has a so-called C-axis rotation control function that controls the orientation of the blade around the machining path, and feeds the cutting blade of the cutting tool along the predetermined machining path while controlling the attitude so as to face the normal direction. This allows the cutting action to proceed. This type of processing machine only needs to have a rotation control function around the axis of the tool spindle by providing the rotation motor such as an encoder in addition to the high-speed rotation output function for the tool spindle drive motor. A milling machine and a machining center equipped with this type of drive motor have already been provided as general-purpose processing machines.

FIGS. 1 and 2 show a cutting tool mounted on a tool spindle of such a processing machine via a hail processing holder. 1 and 2, the tool spindle 8 of the processing machine has a tool mounting hole 9 at the lower end thereof, and the mounting portion 12 of the hail processing holder 10 is located in the tool mounting hole 9 at the center of the spindle. The holder 10 is mounted so that the shaft centers thereof are aligned with each other, and is fixed by an appropriate set screw 13. A holding portion 14 for the cutting tool 30 is provided in a region below the mounting portion 12 of the hail processing holder 10.
The holding groove 16 into which the shank portion 32 of the cutting tool 30 is inserted is formed at the lower end of the, and the shank portion 32 inserted into the holding groove 16 is fixed by the set screws 15 and 15.
The cutting tool 30 is held by the hail processing holder 10 by being fixed.

The hail processing holder 10 has a slit in the holding portion 14, for example, a slit 18 formed so as to be inclined with respect to the holder axis, as shown in the drawing.
When the cutting tool 30 held at the lower end moves the work W in the cutting direction shown in FIG. 2 and the cutting resistance of the work W acts on the bite cutting blade 34 in the process of cutting, the work W is elastically deformed around a fixed fulcrum. As a result, the cutting blade 32 has a structure in which the cutting force is buffered so that the cutting blade 32 smoothly advances the cutting action along the processed surface of the workpiece W.

1 and 2 show a state in which the cutting tool 30 is mounted on the tool spindle 8 of the processing machine. In the cutting method for the work W according to the present invention, first, an end mill or the like is used. Using the milling system rotary cutting tool described above, a step of roughly removing an unnecessary portion of the work W by rough cutting is performed. Therefore, in such a rough cutting process, a rotary cutting tool (not shown) of that kind is mounted in the tool mounting hole 9 of the tool spindle 8, and rough cutting is performed by high-speed rotation of the tool spindle 8. In addition, unlike this, a roughing process using a rotary cutting tool in another machine tool is completed for the work W in advance, and such a work W is equipped with a cutting tool 30 shown in FIGS. 1 and 2. Needless to say, the procedure may be such that it is mounted on the work table of FIG.

The axis "C" shown in FIGS. 1 and 2 indicates the axis when the tool spindle 8 controls the rotation of the C axis. The C axis simultaneously rotates when the tool spindle 8 rotates at high speed. It can be understood that it matches the axis. Then, in carrying out the cutting method of the present invention, as will be described later, the blade front surface 30a of the cutting bite 30 on which the cutting blade 34 is formed is mounted so as to include the C axis, and the cutting blade 34 is also included.
Has a structure in which it is formed only on one side with respect to the C-axis in the blade front surface 30a, and a relief portion 36 is formed on the other side. This point will be described in more detail with reference to FIG.

As clearly shown in FIG. 3, a cutting blade 34 is formed in the blade front surface 30a at the cutting edge portion of the cutting tool 30, and a relief 34a is provided at the back of the blade. Further, when the cutting bite 30 is mounted, the blade front surface is provided on the side opposite to the cutting blade 34 with respect to the rotation axis A in the blade front surface 30a that is mounted so as to match the C-axis on the processing machine side, and has the relief portion 36. A half region of 30a forms a support portion for the cutting blade 34, and at this time, a relief portion is provided with respect to the rotation envelope B defined when the cutting blade 34 rotates around the rotation axis A. 36 is provided so as not to project from the region inside the rotation envelope B. That is, the relief portion 36 is formed as a portion that does not interfere with the work W in the rotary cutting process.

Referring again to FIGS. 1 and 2,
In the feeding process in which the cutting tool 30 advances in the cutting direction indicated by the arrow in FIG. 2, the cutting blade 34 of the cutting tool 30 exerts a cutting action according to the relative linear or curved displacement with respect to the work W, at which time, the desired operation is performed. C-axis rotation control is performed via the hail processing holder 10 in accordance with the machining shape of the cutting tool, and the cutting blade 34 of the cutting tool 30 always maintains the attitude in the normal direction with respect to the processing trajectory while performing the hail cutting processing. To progress.

On the other hand, when the tool spindle 8 rotates about the axis of rotation which coincides with the C axis, the cutting blades 34 of the cutting tool 30 rotate together, so that the cutting blades 34 are relatively moved with respect to the work W. It can be understood that, while rotating and displacing, the abutting and engaging are performed once in one rotation, and at that time, the rotary cutting action according to the depth of cut is performed, and the cutting allowance of the work W is deleted or gradually reduced. Moreover, the radius of gyration of the rotary cutting action matches the radius when the attitude of the cutting blade 34 is controlled according to the rotation of the C axis. In other words, the cutting allowance remaining on the work surface of the workpiece by being cut by the rotary cutting action always advances so that the allowance of a shape similar to the desired target machining shape is left.

As a result, as shown in FIG. 4, for example, in comparison with the rotary contour Tb of a rotary cutting tool such as an end mill,
The rotation contour Ta of the cutting blade 34 of the cutting tool 30 is originally
Since it is selected for the purpose of cutting the desired target machining shape D, in the corner of the work W, the region F further inside the contour line E of the cutting allowance remaining by the rotary cutting tool can also be deleted. You can do it. Therefore, the rotational cutting action of the cutting tool 30 advances the cutting process to a state where a critical amount of cutting allowance sufficiently close to the desired target machining shape remains, and only the critical amount of cutting allowance is finally given. Cutting tool 3 including C-axis rotation control until it matches the desired machining shape
By advancing the hail cutting while performing the attitude control of 0, the cutting with good cutting efficiency can be advanced.

As shown in FIG. 5, a cutting tool 30
In the process of performing the rotary cutting action, it is inevitable that a slight amount of the cutting mark K remains. However, such a cutting trace K itself is a very small amount, and is a very small cutting allowance remaining along the contour close to the target machining shape as a critical cutting allowance. Therefore, the same cutting tool 30 is used. It can be easily deleted in the final cutting and finishing cutting process carried out. And in this hail cutting,
Since a small amount of cutting is performed, it is possible to cut and form a good finished surface on the processed surface of the work W.

[0022]

As can be understood from the above description of the embodiments of the present invention, according to the present invention, a cutting tool having a specific single-edged shape held by a hail processing holder is used for cutting a workpiece. A rotation around the axis of rotation that matches the C-axis rotary feed of the processing machine is applied to the same cutting tool to perform a rotary cutting action until only a predetermined amount of remaining cutting allowance remains.
The cutting is driven in, and the remaining cutting allowance is finally finished by the hail cutting including the C-axis rotary feed control by making full use of the same cutting tool, so that the machining efficiency can be significantly improved compared with the past and work machining The processing accuracy of the surface can also be significantly improved compared to the conventional one. Especially in the corner processing of the work, by rotating the cutting tool, it is possible to drive up to the same cutting allowance as the flat part, so compared with the case of using the rotary cutting tool, the finishing cutting process It is possible to significantly reduce the processing time of.

[Brief description of drawings]

FIG. 1 is a front view showing a state where a cutting tool used for carrying out a cutting method according to the present invention is mounted on a tool spindle of a processing machine via a tool holder.

FIG. 2 is a side view including a partial cross section taken along line 2-2 of FIG.

FIG. 3 is an enlarged partial view for explaining a shape condition of a cutting edge portion of a cutting tool used for carrying out the cutting method of the present invention.

FIG. 4 is a schematic view illustrating the operation of the cutting method according to the present invention in the process of cutting a corner of a work.

FIG. 5 is a schematic view illustrating a cutting mark generated in a rotary cutting process by a cutting tool.

[Explanation of symbols]

 8 ... Tool spindle 9 ... Tool mounting hole 10 ... Hail processing holder 12 ... Mounting part 14 ... Holding part 16 ... Holding groove 18 ... Slit 30 ... Cutting bit 32 ... Shank part 34 ... Cutting edge 36 ... Relief part A ... Rotating shaft center C ... C axis rotation center D ... Target machining shape W ... Work

Claims (1)

[Claims] 1. A cutting tool held by a hail processing tool holder mounted on a tool spindle of a processing machine capable of rotating the C-axis around the axis of the tool spindle along with the cutting rotation of the tool spindle. A cutting method in which a cutting action by feeding in the trajectory direction is sequentially applied and a work is consistently cut with a single cutting tool, wherein the cutting tool is in a plane including the axis of the tool spindle, and, It is formed so as to have a cutting blade extending only on one side of the shaft center, and the rotary cutting action is given to the cutting tool by the rotation of the tool spindle, so that the workpiece is subjected to a predetermined processing for a predetermined processing shape. A step of performing rotary cutting with a margin left, and a step of performing finish cutting to remove the machining allowance by giving only a feed along a trajectory corresponding to the predetermined machining shape to the cutting tool. And a cutting method.