JP2003011037A - Work processing method by NC processing machine and tool path data creation method used in the processing method - Google Patents

Abstract

(57) [Problem] To provide a work processing method using an NC processing machine, which can efficiently and accurately process a work and effectively prevent breakage of a tool. SOLUTION: In a work processing method using an NC processing machine, prior to performing surface processing and contour processing on a work 1, a cornering process for processing a casting allowance outside a processing reference line is performed. In the surface machining, the retraction operation is not required, the number of machining steps can be significantly reduced, the machining efficiency can be improved, and the machining area does not need to be extended, so that the tool path data can be easily created. In the contour processing, the cutting width is stabilized and the tool length can be suppressed, so that breakage of the tool can be effectively prevented, and the cutting accuracy and the cutting speed can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for machining a work by an NC machine tool, and in particular, machining a work material such as a die using a tool having a spherical cutting edge at its tip, for example, a ball end mill. The present invention relates to a method and a tool path data creating method used in the machining method.

[0002]

2. Description of the Related Art In CAD / CAM systems, etc., N
C When machining a work using a ball end mill with a machine tool, for example, tool path data for performing surface machining of the machining area and contour machining of the vertical wall portion using the die drawing and product data Are created, and the tool path data thereof are given to the NC machine tool to perform surface processing and contour processing.

Conventionally, when creating the above-mentioned tool path data, for example, in a work 10 shown in FIG. 5, a shape surrounded by a machining reference line 11 composed of straight lines and curves as shown in FIG. In this case, in the surface machining, the tool path data is created according to the machining method (contour machining, one-way scan machining, bidirectional scan machining, etc.) based on the shape data, and in the contour machining, the machining reference line 11 The contour line 12 that is simply offset to the outside is created as tool path data through which the center of the tool 13 passes.

[0004]

By the way, in the conventional processing method, when the work has a complicated processed shape and a height difference, such as a shearing type press die used for manufacturing an automobile body. It is necessary to create the above tool path data in consideration of the casting cost.

That is, for example, when surface processing is performed prior to contour processing, as shown in the sectional view of FIG.
In consideration of the casting allowance 16 above, the transfer operation (retract operation) of the tool 13 along the shape needs to be performed at a position not in contact with the shape surface 15 as shown in FIG. There is a concern that processing efficiency will decrease. Further, depending on the shape of the machining reference line 11, it is necessary to extend the shape surface, so the shape data cannot be used as it is, and the machining area in which the shape surface is enlarged is set in consideration of the casting allowance 16, and the tool path data is set. Since it is necessary to create the data, it is feared that troublesome data creation will occur and the data creation man-hour will increase.

Further, when the contouring is performed prior to the surface machining, the cutting width d as seen from the side of the tool axis includes the casting allowance 16 as shown in FIGS. 9 (a) and 9 (b). Change with time, which causes interference between the work 10 and the tool holder, and it is necessary to use a tool having a long blade portion as the tool 13, which causes deterioration of machining accuracy and also causes There is a risk of causing damage and a decrease in cutting speed.

Therefore, a first object of the present invention made in view of the above points is to machine a work efficiently and accurately with the NC machining machine and to effectively prevent damage to the tool. To provide a method.

A second object of the present invention is to provide a tool path data creating method which can easily create tool path data used in the above machining method.

[0009]

According to another aspect of the present invention, there is provided a method for machining a workpiece by an NC machining machine, which achieves the first object. It is characterized in that, before the contouring is performed, a cornering process for machining the casting margin outside the machining reference line is performed.

According to the first aspect of the invention, since the cornering process is performed prior to the surface processing and the contour processing, the surface processing processing region and the contour processing region can be clearly separated. Therefore, the retract operation is not required for surface machining, so the machining man-hours can be greatly reduced, the machining efficiency can be improved, and it is not necessary to extend the machining area. Instead, it becomes possible to easily create tool path data.

In the contour processing, the width of cutting is stable,
Since the tool length can be suppressed, it is possible to effectively prevent damage to the tool and improve the cutting accuracy and the cutting speed.

According to a second aspect of the present invention which achieves the second object, in the tool path data creating method for performing the cornering process according to the first aspect, at each point on the machining reference line of the work, A step of setting a shape assumed surface in contact with the shape surface within a predetermined distance range considering the tool diameter and the finishing allowance viewed from the tool axis direction, and a direction vector on the shape assumed surface from each point on the machining reference line and A step of setting a tool axis direction vector for contour machining, obtaining a combined vector of the direction vector on the above-mentioned shape assumed surface and a tool axis direction vector for contour machining, and using the tool from the point of the machining reference line in the combined vector direction. A step of obtaining a tool center point at a desired distance in consideration of a diameter and a finishing allowance, and a step of connecting the tool center points corresponding to respective points on the machining reference line to generate a continuous curve. And, characterized by creating a tool path data for the angle out processing based on the above curve.

According to the invention of claim 2, from the desired shape data, the machining reference line, the tool information used, and the finishing allowance data,
It is possible to easily create tool path data for corner forming for efficiently machining the casting allowance outside the machining reference line.

According to a third aspect of the present invention, in the tool path data creating method according to the second aspect, further, when viewed from the tool axial direction of the contour processing, the bending and the backward portion of the curve are removed to adjust the curve. It is characterized in that it has a step and creates tool path data for performing the above-described cornering processing based on the prepared curve.

According to the third aspect of the present invention, since the tool path data in which the bending of the curve and the retrograde portion are removed is created, it is possible to efficiently perform the cornering process.

According to a fourth aspect of the present invention, in the tool path data creating method according to the second or third aspect, the curve is repeatedly generated while reducing the desired distance, and the cornering is performed based on each curve. It is characterized in that tool path data for machining is created.

According to the fourth aspect of the present invention, it is possible to easily obtain the tool path data for the cornering processing by cutting a plurality of times.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a method for machining a work by an NC machining machine and a method for creating tool path data used in the machining method according to the present invention will be described below with reference to FIGS. 1 to 4.

FIG. 1 is a diagram for explaining a work machining method. As shown in FIG. 1, according to the present embodiment, prior to performing surface machining and contour machining of a workpiece 1 using a tool 2 such as a ball end mill, a machining reference line based on tool path data for corner machining. Square corner processing is performed to process the casting allowance on the outside of.

As described above, by performing the cornering process for machining the casting allowance outside the machining reference line prior to the surface machining and the contour machining of the work 1, the machining region of the surface machining and the machining region of the contour machining are performed. And can be clearly separated.

Therefore, since the retracting operation of the tool 2 is unnecessary in the surface machining, the machining man-hours can be greatly reduced, the machining efficiency can be improved, and the machining area need not be extended. The tool path data can be easily created without any jamming. Further, in the contour processing, since the cutting width is stable and the tool length can be shortened, damage to the tool 2 can be effectively prevented, and cutting accuracy and cutting speed can be improved.

FIGS. 2 to 4 show an embodiment of a method for creating tool path data for performing the above-described cornering process. FIG. 2 is a flowchart, FIGS. 3 (a) and 3 (b),
FIG. 4C is a diagram showing three setting modes of the vector setting according to the flowchart of FIG. 2, and FIG.

As shown in FIG. 2, first, information such as a machining shape, a machining reference line, a tool diameter R used, and a finishing allowance e is input (step S1), and an initial value of an arbitrary distance L is set (step S1). S2). Here, the initial value of the arbitrary distance L is set so that at least distance L> tool diameter R used + finishing allowance e is satisfied.

Next, the distance L> use tool diameter R + finishing allowance e
It is determined whether or not (step S3). First, the distance L>
Since it is the tool diameter R used + the finishing allowance e, next, in order to prevent the tool from biting into the shape surface, the machining reference line is made into a series of points, and each point on the machining reference line is changed according to the shape surface. As shown in FIGS. 3B, 3B, and 3C, the hypothetical shape surface 4 that contacts the shape surface 3 is set within the range of the distance L when viewed from the tool axis direction (step S4).

After that, a direction unit vector A on the assumed shape plane 4 and a tool axis direction unit vector B for contour machining are set from each point of the machining reference line (step S5), and a combined vector C thereof is obtained (step S5). S6), the vector C
A point (tool center point) D at a distance L from the point of the machining reference line in the direction of is calculated (step S7).

Thereafter, the distance L is corrected to be small (step S8), and the operation from step S3 is repeated,
Distance L ≤ tool diameter R + finishing allowance e, that is, step S3
If the determination result in step S1 is NO, the tool center point D is connected for each distance L to generate a continuous curve (step S).
9). That is, when the distance L = the tool diameter R + the finishing allowance e,
As shown in FIG. 4, the pipe 5 is drawn with the radius R of the tool diameter R + finishing allowance e with the R stop of the line in contact with the surface of the vertical wall as the center line, and the line intersecting the vector C is the square tool center point D.
And the tool center point D of the tool radius R + finishing allowance e is connected to generate a continuous curve.

After that, the curve group for each distance L obtained in step S9 is adjusted as viewed from the tool axial direction of the contour processing, and the bending and retrograde portions are removed (step S10). It is converted as a machining path to obtain tool path data for corner machining (step S11). If the casting allowance is excessive with respect to the tool diameter used, the position of the tool center point D is set large in step S7.

This makes it possible to easily create tool path data for corner cutting from the information such as the machining shape, machining reference line, tool diameter R used, and finishing allowance e.

[0029]

As described above, according to the work machining method by the NC machining machine of the present invention, since the cornering machining is performed prior to the surface machining and the contour machining, the machining area of the surface machining and the machining area of the contour machining are performed. Can be clearly separated, which allows the workpiece to be processed efficiently and accurately, and
It is possible to effectively prevent damage to the tool.

Further, according to the tool path data creating method of the present invention, the tool path data for performing the above-mentioned corner forming can be easily obtained from desired shape data, processing reference line, tool information used, and finishing allowance data. Can be created.

[Brief description of drawings]

FIG. 1 is a diagram illustrating an embodiment of a work machining method by an NC machining machine of the present invention and a tool path data creation method used in the machining method.

FIG. 2 is a flowchart showing an embodiment of a tool path data creating method according to the present invention.

FIG. 3 is a diagram showing three setting modes of vector setting according to the flowchart of FIG.

FIG. 4 is a diagram showing a manner of setting a center point of a square-cutting tool.

FIG. 5 is a diagram showing an example of a work.

FIG. 6 is a diagram for explaining a conventional processing method for the workpiece shown in FIG.

FIG. 7 is a cross-sectional view for explaining surface processing by a conventional processing method.

FIG. 8 is a diagram for explaining a retracting operation by surface processing, similarly.

FIG. 9 is a cross-sectional view for explaining contour processing by a conventional processing method.

[Explanation of symbols]

1 work 2 tools 3 Shape plane 4 Shape assumption plane 5 pipes A unit vector B unit vector C composite vector D Tool center point R Tool diameter used e Finishing fee

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kenichi Hashimoto             Fuji, 7-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo             Heavy Industry Co., Ltd. (72) Inventor Tomonori Shimoyama             Fuji, 7-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo             Heavy Industry Co., Ltd. (72) Inventor Naoki Watanabe             Fuji, 7-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo             Heavy Industry Co., Ltd. F-term (reference) 5H269 AB05 BB03 BB05 BB08 CC02                       CC11 CC17 QA02

Claims (4)

[Claims] 1. A work machining method using an NC machining machine, characterized in that prior to performing surface machining and contour machining on a work, a corner machining for machining a casting margin outside a machining reference line is performed. Work processing method by NC processing machine. 2. The method for creating tool path data for performing cornering according to claim 1, wherein the tool diameter and finishing allowance are taken into consideration at each point on the machining reference line of the workpiece when viewed from the tool axis direction. A step of setting a shape assumed surface in contact with the shape surface within a predetermined distance range, a step of setting a direction vector on the shape assumed surface and a tool axis direction vector of contour processing from each point on the processing reference line, A composite vector of a direction vector on a hypothetical surface and a tool axis direction vector for contour machining is obtained, and a tool center point at a desired distance from the point of the machining reference line in the composite vector direction in consideration of the tool diameter and finishing allowance. And a step of connecting the tool center points corresponding to the points on the machining reference line to generate a continuous curve, and performing the cornering machining based on the curve. Tool path data generating method characterized by creating a tool path data Utame. 3. Further, when viewed from the tool axial direction of the contour processing,
3. A step of removing a bending portion and a retrograde portion of the curve to adjust the curve, and tool path data for performing the corner forming process is created based on the adjusted curve.
Tool path data creation method described in. 4. The curve is repeatedly generated while reducing the desired distance, and tool path data for performing the corner forming is created based on each curve. The tool path data creation method described in 3.