JP2002132315A - Method and device for processing path generation and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for processing path generation and a recording medium which can generate a processing path with a small tool load without greatly decreasing cutting efficiency. SOLUTION: A basic processing path generation part 12 inputs information from an input part 1 and generates a basic processing path which offsets a machining shape by a specific quantity. A trochoid processing path generation part 13 extracts a trochoid processing range from the found basic processing path and generates a trochoid processing path within this range. The part outside the trochoid processing range is a flank processing range. An area processing path generation part 15 composes a processing path of the flank processing path and trochoid processing path. Thus, provided are the method and device for processing path generation and the recording medium where a program for it is recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a machining path generating method for creating a machining path in an NC machine tool.

[0002]

2. Description of the Related Art In order to machine a workpiece with an NC machine tool, a machining path generating apparatus for creating a machining path program includes data to be machined by an operator, that is, a machining shape, a machining method, a tool diameter, and a finish. Upon receiving designation of a margin, a cutting width, and the like, a machining path is created based on these. Actually, since the format of the NC program by the NC device differs for each model of the NC machine tool, first, general-purpose machining path information independent of the model is created, and then converted into an NC program corresponding to each NC device. A machining path program is created using a post processor.

As shown in FIG. 7, a conventional machining path creating apparatus includes an input section 1, a contour machining path creating section 2, an area machining path creating section 3, a pocket machining path creating section 4, a post processor 5, It is composed of The input unit 1 receives an outline of a pocket shape, a height of a pocket upper surface,
Upon receiving input of information such as a pocket bottom height, a tool diameter, a tool radial direction cut width, a tool axial direction cut width, and a finishing allowance, the information is output to the contour machining path creating section 2 and the area machining path creating section 3.

The contour machining path creating section 2 and the area machining path creating section 3 generate a plurality of contour machining paths by sequentially offsetting the machining paths by the cutting width in the tool radial direction while taking the finishing margin into consideration. Are sequentially connected to create a spiral processing path (region processing path) as shown in FIG. Here, to create the contour machining path, specifically, first, a first contour machining path offset inward from the desired machining shape contour by the sum of the tool radius and the finishing allowance is created, and the first contour machining path is created. A second contour machining path that is offset inward from the machining path by the cutting width in the tool radial direction is created. Hereinafter, similarly, the third to k-th contour machining paths are created. This is repeated until a contour machining path cannot be created inside, and a plurality of contour machining paths are obtained. At the time of actual machining, cutting is performed sequentially from the k-th contour machining path. Processing by a contour processing path along such a processing shape contour is referred to as “side processing”.

[0005] The pocket machining path creation unit 4 is configured to calculate from the height of the pocket upper surface to the height of the sum of the pocket bottom height and the finishing allowance.
A cutting plane height is sequentially determined for each cutting width in the tool axis direction, and a region processing path is sequentially created and combined for each cutting plane height to create a pocket processing path.

[0006]

When the pocket shape is rough-cut by the side machining according to the spiral machining path created by the conventional machining path generating apparatus, the center of the spiral (the k-th contour machining path) is removed. At the start of processing, at the time of sudden bending of a path appearing during processing, or at the time of processing of a reciprocating path, the contact length between the tool and the workpiece becomes extremely large as compared with the side-cutting state on one side of the straight portion during processing.
That is, a state occurs in which the processed portion of the tool extends from the side surface to the entire front surface in the traveling direction (groove processing state). In this state, the cutting load of the tool becomes extremely large, and the tool is damaged or the tool is significantly worn due to generation of cutting heat.

For this reason, when machining is performed according to the path created by the conventional machining path generating apparatus, the feed rate is set to be low so that the tool load does not become excessive, assuming that the tool load becomes maximum. . For this reason, even in the side cutting state on one side, which occupies most of the roughing processing, the feed speed is reduced in consideration of the load, and there is a problem that the processing efficiency is reduced as a whole.

[0008] In view of this, various measures have been taken such as recognizing a portion having a large load on the route and reducing the feed speed only at that portion. However, even in this case, tool wear due to an increase in cutting heat in the groove processing state cannot be avoided.

On the other hand, trochoidal machining is known as a method for performing grooving while reducing the tool load. Trochoidal machining is a method of performing machining by moving a tool in a groove direction while making a circular motion. Therefore, the tool moves while drawing a spiral as a whole. Therefore, the width of the groove processed by the trochoidal processing is the sum of the tool diameter and the diameter of the circular motion. Specifically, a processing path in trochoid processing is as shown in FIG. In the trochoidal machining, the contact portion between the tool and the workpiece comes into contact with one side of the side face, and the groove machining does not hit the entire front surface of the tool. For this reason, it is possible to specify the same cutting conditions as the side cutting state of the side processing, and it is possible to perform the groove processing without reducing the cutting speed.

[0010] Ideally, the trochoidal processing is performed in a spiral processing path in which movement along the groove direction and movement of a circle in contact with the groove direction are combined. It can be approximately realized by dividing into pitches of arc movement and adding a path for moving a circle in contact with each division point at each division point. In other words, after performing machining by circular motion of the tool around a certain point, it moves slightly along the machining path,
At the position after this movement, the tool is again circularly moved around a predetermined point. The machining path of the trochoid machining created in this way is as shown in FIG. Hereinafter, the trochoid processing which is approximately realized will be described.

However, in trochoid processing, cutting efficiency is low because half of the circular motion is air cut.

The present invention has been made in view of the above circumstances, and provides a machining path generating method, a machining path generating apparatus, and a recording medium capable of creating a machining path with a low tool load without significantly reducing the cutting efficiency. The purpose is to do.

[0013]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the prior art, the present invention relates to a machining path generating method for machining a machining path formed by offsetting an inputted machining shape by a predetermined amount. A range in which no uncut portion is generated by trochoidal processing when the tool is moved along the path, or a processing range of at least one of the concavely bent portions is a trochoidal processing path, and a processing path other than the range is a side processing path. It is characterized by the following. That is, the present invention is characterized in that a machining path obtained by combining a trochoid machining path and a side machining path is formed inside the machining shape in order to machine a desired machining shape. Thereby, a machining path with a low tool load can be generated while maintaining the cutting efficiency.

Further, according to the present invention, there is provided a method for generating a machining path in which a machining path created by offsetting an inputted machining shape by a predetermined amount is provided. A step of generating a basic machining path by offsetting a predetermined amount, and, based on the diameter of the trochoid circle and the diameter of the tool, of the basic machining path, a range in which uncut portions are not generated by trochoid machining by the trochoid circle, Alternatively, a step of extracting at least one of the predetermined range of the concave bent portion as a trochoid processing range, a step of generating a trochoid processing path in the extracted trochoid processing range, and a step of forming a basic processing path other than the trochoid processing range Extracting as a machining path, and a combined machining path obtained by combining the trochoid machining path and the side surface machining path It is characterized in that it comprises a step to be generated.

Further, according to one aspect of the present invention, the step of generating the trochoid machining path includes generating a machining path in which a predetermined amount of arc is inserted into a concave bending portion of the basic machining path in the extracted trochoid machining range. A trochoid machining path is generated based on the machining path.

Further, according to the present invention for solving the problems of the above-mentioned conventional example, there is provided a machining path generating apparatus for machining an inputted machining shape with a machining path created by offsetting the inputted machining shape by a predetermined amount. Means for generating a basic machining path by offsetting a predetermined amount, and, based on the diameter of the trochoid circle and the diameter of the tool, of the basic machining path, a range in which uncut portions are not generated by trochoid machining by the trochoid circle, Alternatively, means for extracting at least one of the predetermined range of the concave bent portion as a trochoid processing range, means for generating a trochoid processing path in the extracted trochoid processing range, and a basic processing path other than the trochoid processing range Means for extracting the machining path as a machining path, and a combined machining path combining the trochoid machining path and the side machining path. It is characterized in that it comprises means for generating a.

[0017]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a machining path creation device according to this embodiment.
As shown in the figure, the input unit 1 and the basic machining path creation unit 12
A trochoid machining path creating unit 13, a side machining path creating unit 14, a basic machining path correcting unit 20, an area machining path creating unit 15, a pocket machining path creating unit 16, and the post processor 5. I have. Here, the input unit 1
Since the post processor 5 is the same as the conventional one, detailed description is omitted. In the following description, as shown in FIGS. 9 and 10, the trochoidal cutting depth refers to the center of the circular motion of the tool (the center of the trochoid circle) when performing trochoidal machining along the machining path. The trochoid machining maximum width is the sum of the tool radius and the diameter of the trochoid circle. In trochoid machining, machining is performed by an amount obtained by adding the tool radius to this width. Therefore, uncut portions are generated for the width exceeding this.

The input unit 1 includes a machining shape contour line indicating a pocket shape to be machined, a pocket top height, a pocket bottom height, a finishing allowance, and a tool diameter of a machining tool indicating machining conditions, which are input by an operator. Information such as a radial cut width and a tool axial cut width is input and stored. (FIG. 5, step 1)

Subsequently, the basic machining path creating unit 12
In the third round, a first basic machining path, which is a tool center path in which the input machining shape contour is offset inward by the sum of the tool radius and the finishing allowance, is created. For the second and subsequent times, a j-th basic machining path, which is a tool center path in which the j-th basic machining path created last time is offset inward by the cutting width in the tool radial direction, is created. These basic machining paths correspond to contour machining paths in the related art. (FIG. 5, step 2)

The basic machining path creating unit 12 checks whether or not the j-th basic machining path has been created (FIG. 5, step 3). If the j-th basic machining path cannot be created, it is considered that all inward offset processing has been completed, and the area machining path has been completed. The processing jumps to the processing of the creating unit 15 (step 9 in FIG. 5). When the j-th basic machining path is created, the following processing is performed to generate a trochoid machining path.

The trochoid machining path creating section 13 extracts a trochoid machining area from the obtained basic machining path and generates a trochoid machining path in the extracted area. When extracting a trochoid machining range in which no uncut portion remains when trochoid machining is performed in the j-th basic machining path and generating a trochoid machining path in the extracted range, the trochoid machining path creating unit 13 first generates the trochoid machining path shown in FIG. As shown in FIG.
A machining path indicated by a broken line offset inward from the basic machining path by the maximum width of the trochoidal machining is created. here,
Among the intersections of the machining paths indicated by the broken lines, the machining paths outside the intersection of the machining path in which the path element farthest from the path elements constituting the basic machining path is offset (the intersection a in FIG. 3A) are: The machining path obtained by offsetting the path element of one of the basic machining paths is located at a position equal to or less than the maximum width of the trochoid machining from the path element of the opposing basic machining path. In this portion, the trochoid machining can be performed without being left behind.

Subsequently, a trochoid machining path creating unit 13 extracts a trochoid machining range from the basic machining path.
Is the intersection of an arc having a radius corresponding to the maximum width of the trochoid machining centering on the intersection of the machining paths offset from the j-th basic machining path (intersection A in FIG. 3A) (FIG. 3 ( b), and the basic machining path between the intersections is extracted as a trochoid machining range (FIG. 3).
(B) Thick line portion of the j-th basic machining path). The trochoid machining path creating unit 13 also performs
The trochoid processing range is extracted by the same processing.

That is, as shown in FIG. 4A, the trochoid machining path creating unit 13 creates a machining path indicated by a broken line offset inward from the jth basic machining path by the maximum width of the trochoid machining, and intersects the intersection ( An intersection d) in FIG. 4A is obtained. The intersection between the circle having the radius corresponding to the maximum width of the trochoid machining centered on the obtained intersection and the j-th basic machining path (FIG. 4)
Then, the basic machining path between the intersections is extracted as the trochoid machining range (the thick line portion of the jth basic machining path in FIG. 4B). (FIG. 5, step 4)

If a trochoid machining path is created by adding a trochoid circle to the extracted basic machining path in the trochoid machining range as it is, the tool center moves on the machining path. For example, as shown in FIG. At the concave bending portion of the path, the desired processing shape is cut off.

In order to prevent this cutting, the trochoid machining path creating section 13 detects a concave bend from the j-th basic machining path in the extracted trochoid machining range, and as shown in FIG. Is inserted between the j-th basic machining path elements constituting at least the radius R of the trochoid circle, and the j-th basic machining path in the trochoid machining range is corrected. (FIG. 5, step 5)

Further, the trochoid machining path creating unit 13
The j-th basic machining path included in the trochoid machining range is divided for each trochoid machining depth of cut, and a trochoid machining path in which a trochoid circle having a trochoid circle diameter designated for each division position is created (FIG. 3 ( c))
(FIG. 5, step 6).

The side machining path creating unit 14 extracts a portion other than the trochoid machining area extracted by the trochoid machining path creating unit 13 from the j-th basic machining path as a side machining area. Create a machining path combined with the created trochoid machining path (Fig. 3
(C)) (FIG. 5, step 7).

By this processing, a single machining path is created by combining the trochoid machining path and the side machining path for machining the area in the input machining shape.

The basic machining path correcting unit 20 corrects the j-th basic machining path included in the trochoid machining range extracted by the trochoid machining path creating unit 13 into a machining path that is considered to have undergone side machining. In this embodiment, the path element of the j-th basic machining path included in the trochoid machining range (FIG. 3)
(B) The intersection of the machining path obtained by offsetting the j-th basic machining path (the thick line portion of the basic machining path) (the intersection a in FIG. 3A).
Is realized by replacing the arc with an arc having a radius corresponding to the maximum width of the trochoid machining centered at the center. (FIG. 3 (d))
(FIG. 5, step 8)

The corrected j-th basic machining path is used when the basic machining path creating unit 12 creates the (j + 1) th basic machining path. Then, the process jumps to step 2 to execute the next offset processing.

The area machining path creating section 15 creates a transfer path between adjacent machining paths based on a combined machining path of the plurality of side face machining paths and the trochoid machining path created by the above-described processing. An area machining path having a plane height is generated. (FIG. 5, Step 9) Thus, a machining path as shown in FIG. 6 is created for the machining path shown in the prior art in FIG.

The pocket machining path creating section 16 determines the cutting plane height for each cutting width in the tool axial direction from the height of the pocket upper surface to the height of the sum of the pocket bottom height and the finishing allowance,
The machining paths shown in FIG. 6 are sequentially created and combined for each cutting plane height to create a pocket machining path. (FIG. 5, step 10)

The basic machining path creating section 12, trochoid machining path creating section 13, side machining path creating section 14, basic machining path correcting section 20, area machining path creating section 15, and pocket machining path creating section 16 It may be realized as software executed in a CPU (Central Processing Unit). In this case, the CPU reads this software from a computer-readable recording medium,
A processing path is generated.

In the detailed description of the present invention, the processing path generation method has been described by taking the example of area processing in pocket processing as an example. However, the present invention is not limited to the area processing for processing all the areas in the specified processing shape. It goes without saying that the present invention can be applied without departing from the gist of the present invention, such as contour processing for processing along a specified processing shape.

[0035]

According to the present invention, there is provided a method for generating a machining path by machining a machining path created by offsetting an inputted machining shape by a predetermined amount, wherein a method for moving a tool along the machining path is provided. Since a range in which uncut portions do not occur due to trochoidal processing, or a processing range of at least one of the concave and bent portions is set as a trochoidal processing path, and a processing path generating method in which a processing path other than the range is set as a side processing path, a cutting path is used. A machining path with a low tool load can be generated while maintaining efficiency.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a machining path generation device according to the present invention.

FIG. 2 is an explanatory view showing prevention of cutting of a concave bending portion by trochoid processing.

FIG. 3 is an explanatory diagram showing a method of setting a trochoid processing range.

FIG. 4 is an explanatory diagram showing a method of setting a trochoid processing range of a concave bending portion.

FIG. 5 is a flowchart of a machining path generation method according to the present invention.

FIG. 6 is an explanatory diagram showing an example of a machining path created by the machining path generating device of the present invention.

FIG. 7 is a block diagram illustrating a configuration of a conventional processing path generation device.

FIG. 8 is an explanatory diagram illustrating an example of a machining path created by a conventional machining path generation device.

FIG. 9 is an explanatory diagram showing a processing path in ideal trochoid processing.

FIG. 10 is an explanatory diagram showing a processing path in general trochoid processing.

[Explanation of symbols]

1 input section, 2 contour machining path creation section, 3 area machining path creation section, 4 pocket machining path creation section, 5 post processor, 12 basic machining path creation section, 13 trochoid machining path creation section, 14 side machining path creation section, 15 area machining path creation unit, 16 pocket machining path creation unit, 2
0 Basic machining path correction unit.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Koji Tamaoka 2-17-17 Akasaka, Minato-ku, Tokyo F-term in Nihon Unisys Co., Ltd. 5H269 AB05 BB01 BB05 QA01 QA02

Claims (5)

[Claims] In a machining path generating method for machining a machining path created by offsetting an input machining shape by a predetermined amount, no uncut portion is generated by trochoid machining when a tool is moved along the machining path. A processing path generation method, wherein a processing range of at least one of a range and a concave bent portion is a trochoid processing path, and a processing path other than the range is a side processing path. 2. A method for generating a basic machining path by offsetting an input machining shape by a predetermined amount in a machining path generating method for machining an input machining shape by a machining path created by offsetting the input machining shape by a predetermined amount. Based on the diameter of the trochoid circle and the diameter of the tool, at least one of the basic machining path in which no uncut portion is generated by trochoid machining by the trochoid circle or a predetermined range of the concave bent portion is trochoidal. A step of extracting a trochoid machining path in the extracted trochoid machining area; a step of extracting a basic machining path other than the trochoid machining area as a side machining path; the trochoid machining path and the side surface Generating a combined machining path obtained by combining the machining path with the machining path. Forming method. 3. The machining path generating method according to claim 2, wherein the step of generating the trochoid machining path includes the step of inserting a predetermined amount of arc into a concave bending portion of the basic machining path in the extracted trochoid machining range. Generating a trochoid machining path based on the machining path. 4. A machining path generating device for machining a machining path created by offsetting an inputted machining shape by a predetermined amount, comprising: means for offsetting the inputted machining shape by a predetermined amount to generate a basic machining path. Based on the diameter of the trochoid circle and the diameter of the tool, at least one of the basic machining path in which no uncut portion is generated by trochoid machining by the trochoid circle or a predetermined range of the concave bent portion is trochoidal. Means for extracting a trochoid machining path in the extracted trochoid machining area; means for extracting a basic machining path other than the trochoid machining area as a side machining path; the trochoid machining path and the side surface Means for generating a combined machining path obtained by combining the machining path with the machining path. Generating device. 5. A machining path generating program for machining a machining path created by offsetting an input machining shape by a predetermined amount, wherein a basic machining path is generated by offsetting the input machining shape by a predetermined amount. A module, based on the diameter of the trochoid circle and the diameter of the tool, at least one of a range in which no uncut portion is generated by the trochoid processing by the trochoid circle, or a predetermined range of the concave bending portion in the basic processing path. A module for extracting a trochoid machining range in the extracted trochoid machining range; a module for extracting a basic machining route other than the trochoid machining range as a side machining route; and a trochoid machining route. A module for generating a combined machining path combining the side machining path A computer-readable recording medium characterized by storing a machining path generation program including Le and, a.