JP2696206B2 - Automatic part program creation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an automatic part program for automatically creating a program for cutting a planar portion of a work into a predetermined shape using an NC milling machine. It is about the creation method. SUMMARY OF THE INVENTION According to the present invention, in a part program creating method, a figure shape is divided into a workable area and a non-workable area based on a tool diameter automatically selected, and a workable area Outputs the machining data of the tool,
In the non-machinable area, the tool is re-selected and the same processing is applied recursively until there is no non-machinable area. It can be created in a short time. [Prior Art] The conventional part program creation method includes the following steps: a) a step of inputting a graphic definition statement defining a figure; b) a step of inputting a motion definition statement defining a tool path; And a step of creating processing data from the motion definition sentence. In the step b), in particular, in the step b), in order to create accurate and efficient machining data of the designated graphic shape, the programmer pays close attention to the motion definition sentence so as not to leave or cut too much. Had to enter. Therefore, it took a long time to create a part program, and programming errors were likely to occur. Also, considerable experience was required of programmers. That is, with the conventional part program creation method, it is impossible for a beginner to create a part program in a short time. [Problems and Object to be Solved by the Invention] In such a conventional part program creating method,
The exercise definition sentence input required a long time to create a part program, and programming errors were likely to occur. Also, considerable experience was required of programmers to create part programs. Therefore, the present invention solves such a conventional problem. The purpose of the present invention is to eliminate a motion definition sentence inputting step and to automatically create machining data, so that even a beginner can almost completely solve the problem. It is an object of the present invention to provide a method capable of automatically and quickly creating a part program having the above-mentioned graphic shape. [Means for Solving the Problems] The automatic part program creating method of the present invention is an automatic part program creating method for automatically creating a program for cutting a planar portion of a work into a predetermined shape using an NC milling machine. A method for creating a part program, comprising: a first step of defining a first machining area on a computer; a first tool having a first tool diameter; an outer periphery and / or an inner periphery of the first machining area; A second virtual tool center trajectory when the first virtual tool center trajectory is moved along the first virtual tool center trajectory at an intersection where the first virtual tool center trajectories intersect with each other; By separating into a virtual tool center locus that does not process an area other than the first processing area and a virtual tool center locus that also processes an area other than the first processing area, First A third machining area, which is divided into a first machining area that can be machined with the first tool and a first machining area that cannot be machined with the first tool. A fourth step of calculating a first tool center trajectory for moving the first tool so that the entire area of the first workable area can be processed, and the first processing Setting the second machining area so as to include the impossible area, replacing the first tool with a second tool having a second tool diameter smaller than the first tool diameter, and performing the second step A fifth step of performing the following steps, and if there is an area that cannot be machined with the second tool after performing the fifth step, the second tool is replaced with the second tool diameter. The fifth step is performed by replacing the third tool having a smaller third tool diameter with the third tool. Having a sixth step, in this order, in which the replaced tool is replaced with a tool having a smaller tool diameter and the contents of this step are repeated until there are no more areas that cannot be machined with the replaced tool. It is characterized by. In the automatic part program creating method, in addition to the first non-machining region, a circle having a first tool diameter as a diameter and having a center at an intersection at which the first virtual tool center trajectories intersect is included. The fifth step is performed by setting the second processing area as described above. EXAMPLES Hereinafter, the present invention will be described in detail based on examples. FIG. 1 is a flowchart of the process of the automatic part program creating method of the present invention. FIG. 2 is an explanatory diagram of a figure shape used for explaining an embodiment of the present invention. FIG. 3 is a diagram showing a processing area of the embodiment. (A) is for figure shape-1 and (b) is for figure shape-2. (A) First Step In the first step, first, a first processing area is defined on a computer. The shape of the first processing region corresponds to the final shape for performing cutting using a milling machine. Specifically, by inputting the graphic definition sentences of the graphic shape-1 and the graphic shape-2 shown in FIG. 2, the first processing area indicated by the hatched portion in FIG. 3A is defined. I do. (B) Second Step Next, in the second step, it is assumed that the first tool having the first tool diameter is moved along the outer periphery and / or the inner periphery of the first machining area. Is calculated for the first virtual tool center locus. Specifically, the following procedure is followed. First, when creating data for machining the first machining area indicated by the hatched portion in FIG. 3 (a), the tool diameters of the tools required for machining this area are defined by all graphic definitions. A plurality of sentences are automatically selected from the corner information of the sentence, and they are registered in advance in a computer memory (not shown) in descending order. Next, among the registered tool diameter information, the largest one at the present time is stored in the variable r1 and the tool is deleted from the memory of the computer (not shown). FIG. 4 (a) is a virtual tool center locus for the graphic shape-1 in FIG. 2, and FIG. 4 (b) is a virtual tool center locus for the graphic shape-2 in FIG. In addition, the fifth
The figure is a diagram obtained by combining FIG. 4 (a) and FIG. 4 (b). This synthesized virtual tool center locus is the first virtual tool center locus. (C) Third Step Next, in a third step, the first virtual tool center trajectory is defined by an intersection point where the first virtual tool center trajectories intersect with each other, except for the first machining area. Is separated into a virtual tool center trajectory that does not process and a virtual tool center trajectory that also processes an area other than the first processing area, so that the first processing area is First
A first processable area that can be processed by the tool of
It is divided into a first unworkable region that cannot be machined by the first tool. The intersection 3 in FIG. 5 corresponds to the intersection where the first virtual tool center trajectories intersect, and the virtual tool center trajectory that does not machine any part other than the first machining area with the intersection 3 as a boundary And a virtual tool center trajectory that also processes an area other than the first processing area. The shaded area in FIG. 6 corresponds to the first workable area, and the area surrounded by the shaded area and the crescent-shaped area at the upper right of the shaded area in FIG. Corresponding to (D) Fourth Step Next, in a fourth step, a first tool center locus for moving the first tool so that the entire area of the first workable area can be machined. Is calculated. As a result, a first tool center trajectory expressed in the order of 1 to 36 as shown in FIG. 8, for example, can be obtained. (E) Fifth Step Next, in a fifth step, first, a second processing area is set so as to include the first unworkable area. This is to prevent the area other than the first workable area from being machined using the first tool in order to prevent excessive shaving due to interference with other graphic shapes. When setting the second machining area, in addition to the first non-machining area, a first tool diameter is set as a diameter, and an intersection point where the first virtual tool center trajectories intersect with each other is set as a center. It can also include a circle to be made. The hatched area in FIG. 7 corresponds to the second processing area in this case. After that, the first tool is replaced with a second tool having a second tool diameter smaller than the first tool diameter, and the steps after the second step are performed. (F) Sixth Step Next, in a sixth step, if there is an area that cannot be machined with the second tool after performing the fifth step, the second tool is replaced with the second tool. Third smaller than the second tool diameter
The fifth step is performed by replacing the third tool with the third tool diameter. Then, the contents of this process are repeated by replacing the replaced tool with a tool having a smaller tool diameter until there is no more region where machining with the replaced tool is impossible. Then, when there is no longer any region that cannot be machined with the replaced tool, all processes have been completed. [Effects of the Invention] As described above, according to the present invention, it is possible to perform machining with the used tool while automatically selecting the tool to be used sequentially, no matter how complicated the designated graphic shape is. In order to process the area, and for the area that cannot be machined, re-select the tool to be used and apply the same processing automatically until there are no more unworkable areas. Part programs can be created easily and in a short time without any input process. In the past, considerable experience and time were required for creating a part program. However, the present invention enables even a beginner to create a part program simply, quickly, and accurately, which is extremely useful.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flow chart of a processing method of a workpiece processing method by an NC milling machine according to the present invention. FIG. 2 is an explanatory diagram of a figure shape used for explaining an embodiment of the present invention. FIG. 3 is a diagram showing a first processing region of the present embodiment,
(A) is a plan view and (b) is a cross-sectional view. FIG. 4 is a diagram showing a virtual tool center trajectory in the case of machining with the first tool (r1), where (a) is for figure shape-1 and (b) is for figure shape-2. belongs to. Fifth
The figure shows the first virtual tool center locus. FIG. 6 is a diagram showing a first workable area. FIG. 7 is a diagram showing a second processing area. FIG. 8 is a diagram showing a first tool center locus in the first workable area.

Claims (1)

(57) [Claims] An automatic part program creating method for automatically creating a program for cutting a planar portion of a workpiece into a predetermined shape using an NC milling machine, wherein a first machining area is defined on a computer. A first step of calculating a first virtual tool center locus when the first tool having the first tool diameter is moved along the outer periphery and / or the inner periphery of the first machining area; Step 2, the first virtual tool center trajectory, the intersection of the first virtual tool center trajectory intersect, a virtual tool center trajectory that does not process the area other than the first processing area, The first machining area can be machined by the first tool by separating the area other than the first machining area into a virtual tool center trajectory that also machine the area. 1 workable area, A third step of dividing into a first unworkable region that cannot be machined by the first tool, and a first process so that the entire region of the first workable region can be machined. A fourth step of calculating a first tool center trajectory for moving a tool, and setting a second machining area so as to include the first unworkable area; Replacing the second tool with a second tool having a second tool diameter smaller than the first tool diameter, performing a fifth step of performing the steps after the second step, and the second step after performing the fifth step. If there is an area that cannot be processed with a tool, the fifth step is performed by replacing the second tool with a third tool having a third tool diameter smaller than the second tool diameter, Until there are no more areas that cannot be machined with the replaced tool
A method for creating an automatic part program, comprising, in this order, a sixth step of replacing the replaced tool with a tool having a smaller tool diameter and repeating the contents of this step. 2. 2. The automatic part program creating method according to claim 1, wherein, in addition to said first non-machining area, an intersection point where said first virtual tool center locus intersects with a first tool diameter as a diameter. A method for creating an automatic part program, comprising setting a second machining area so as to include a center circle and performing the fifth step.