JPH0363707A - Nc data generating device - Google Patents

Abstract

PURPOSE:To prevent a large amount of cutting from being left even if a worker, etc., do not judge the depth by generating a curved surface from a negative form three-dimensional shape, calculating an intersection line with a plane at every serration quantity, and generating cutting NC data and piercing NC data. CONSTITUTION:By a curved surface generating means, a curved surface is generated from a negative from three-dimensional shape in a finish shape storage means. An intersection line arithmetic means calculated an intersection line with a plane at every serration quantity from the generated curved surface and working start depth stored in a working condition storage means. A thrust-in point deciding means decides a position relation of a closed loop of an offset intersection line and a thrust-in point of a piercing tool from the calculated intersection line, a cutting NC data generating means generates NC data of cutting executed by a cutting tool, and a piercing NC data generating means generates NC data of piercing executed by a piercing tool. In such a way, the piercing depth can be calculated by only inputting the negative form three-dimensional shape being a finish shape without necessitating a decision of a worker, etc., and it does not occur that a large amount of cutting is left in the vicinity of the bottom face.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to an NC data creation device for rough machining a female three-dimensional shape on a workpiece to be machined.

[Prior art]

Conventionally, when roughing a female three-dimensional shape,
Use a drill or other tool with a larger diameter than the cutting tool to make a hole in advance at the position where the cutting tool, such as an end mill, will penetrate, and then insert the end mill, etc. into the hole to make a hole for each increment amount. Cutting is performed for each plane based on the depth contour lines. When drilling with a tool such as the drill mentioned above, the depth of penetration should be determined when the bottom surface of the female three-dimensional shape to be rough-cut is not flat, etc.
In particular, with safety in mind, the holes made by a drill or the like on the bottom were determined by the operator with enough margin that the tip of the tool could not reach.

[Problem to be solved by the invention]

As mentioned above, the operator grasps the three-dimensional female shape that is the finished shape and indicates the depth when drilling with a drill, etc., so the depth of the hole is well below the bottom of the shape. It is being terminated. For this reason, even when rough cutting is performed for each plane based on contour lines using a cutting tool such as an end mill, the hole drilling using the above-mentioned drill etc. can only cut to the depth, so a large amount of machining allowance is left near the bottom of the female three-dimensional shape. I will leave it behind. In order to reduce the above-mentioned machining allowance, when drilling with a pre-processing such as a drill, ignore the depth and use a cutting tool such as an end mill to cut to the bottom of the female three-dimensional shape, which is the finishing depth. , a large load is placed on the cutting edge. The present invention has been made to solve the above-mentioned problems, and its purpose is to eliminate the need for the operator to judge the depth of a hole using a drill, etc. It is calculated just by inputting the original shape, and the hole can be drilled to the maximum depth for that shape, and subsequent rough cutting with a cutting tool such as an end mill can be performed to the same depth. To provide an apparatus for creating NC data for rough cutting without leaving any machining allowance.

[Means to solve the problem]

The structure of the invention for solving the above problem is that, as the concept is shown in FIG. NC for machine tools that rough-cut three-dimensional shapes
The apparatus for creating data includes a finishing shape memory means for storing a female three-dimensional shape that is the finished shape of the workpiece, a diameter of the hole and a cutting tool, and a predetermined plunge of the cutting tool into the material of the workpiece. a machining condition storage means for storing tool information such as the amount of increments that is a unit depth, machining information such as a plunge point set in advance for the workpiece by the hole drilling and cutting tool, and a machining start depth; A curved surface generating means for creating a curved surface from the female three-dimensional shape stored in the finishing shape memory means; an intersection line calculation means for calculating an intersection line with the plane of the plane, and a hole size calculated from the intersection line calculated by the intersection line calculation means and the diameter of the tool stored in the machining condition storage means. A plunge point determining means calculates an offset intersection line offset by the tool radius and determines the positional relationship between the closed loop and the plunge point of the tool, When it is determined that the loop is within the closed loop, an offset intersection line is calculated by offsetting the intersection line calculated by the intersection line calculation means and the diameter of the cutting tool stored in the machining condition storage means by the tool radius, and the cutting cutting NC data generation means for generating NC data of cutting by the cutting tool according to the tool path based on the offset intersection line of the tool and information stored in the machining condition storage means; and drilling by the penetration point determination means. When it is determined that the plunge point of the tool is outside the closed loop, the hole is drilled based on the information stored in the machining condition storage means from the plane depth calculated by the intersection line calculation means to the plane depth l increments before the plane depth. is characterized by comprising a drilling NC data generation means for generating NC data of drilling by a tool.

[Effect]

A curved surface is created by the curved surface creation means from the female three-dimensional shape which is the finished shape stored in the finished shape memory means. Next, the intersection line calculation means calculates the intersection line between the created curved surface and the plane for each increment amount from the machining start depth stored in the machining condition storage means. Here, the plunge point determination means determines the positional relationship between the calculated intersection line and the closed loop of the offset intersection line, which is calculated by offsetting and sorting by the radius of the tool, and the plunge point of the tool. do. Then, when the cutting NC data generation means determines that the plunge point is within the closed loop of the offset intersection line of the tool, the cutting NC data generation means stores the offset intersection line calculated by offsetting the tool radius of the cutting tool in the machining condition storage means. NC data of cutting by the cutting tool is generated according to the tool path based on the information obtained. In addition, the drilling NC data generation means stores the machining conditions up to the plane depth one increment before the plane depth from which the intersection line was calculated at that time if the plunge point is not within the closed loop of the offset intersection line of the tool. Based on the information stored in the means, drilling is performed by NC of drilling with a tool.
Generate data.

【Example】

The present invention will be described below based on specific examples. In FIG. 2, 10 is a numerical control device, and this numerical control device 10 includes servo motor drive circuits DUX, DUY.
, DUZ1 Sea/;r7 Sm7) o-ra 11 are connected via the enclosure interface. On the other hand, 20 is a machining center type machine tool controlled by the numerical control device 10 having the above configuration, and includes the servo motor drive circuits DUX and DUY. Servo motor 21 driven by each of the DUZ
, 22 and 23, the relative position between the workpiece table 25 that supports the workpiece W and the spindle head 24 that supports the spindle 26 driven by the spindle mower 53M is three-dimensionally changed. . Further, 27 is a tool magazine that holds a plurality of types of tools, and the tools in the tool magazine 27 are selectively mounted on the spindle 26 by the magazine indexing device in the enclosure and the tool changing device 28, and the tools are inserted into the workpiece W. Processing is performed. The sequence controller 11 also includes a computer 1.
2 and a main shaft motor drive circuit 15 that controls the rotation speed of the main shaft motor 53M. This computer 12 has a microprocessor 12a. Clock signal generation circuit 12b, ROM12c, RAM1
2d, fixed disk t28. Interface 12f, 1
Mainly composed of 2g and 12h, interface 1
A keyboard 13 and a CRT display device 14 are connected to 2h. Next, the processing procedure of the MPU 12a will be explained based on the flowchart of FIG. 3, with reference to FIGS. 4(a) and 4(b), which are explanatory diagrams showing tool information and machining information. First, in step 100 of achieving the finished shape memory means, point group coordinate information representing the female three-dimensional shape which is the finished shape of the workpiece W is stored in step 1 of achieving the processing condition memory means.
In 02, tool information such as tool diameter and tool length, the plunge point indicating where in the plane of the three-dimensional shape the hole should be drilled, and the machining start depth at which the hole is to be drilled with the drill determined from the design drawing, etc. and the machining information consisting of the machining end depth indicating the depth at which no uncut material will be left when drilling at the plunge point (for example, a point on a three-dimensional curved surface or a deeper position) from the keyboard 13. RAM12d
Enter. Next, the process moves to step 104 for achieving a curved surface creation means, and a curved surface is created by interpolating between each point from the point group coordinate information of the female three-dimensional shape stored in step 100. Then, the process moves to step 106, and SZ (start Z coordinate), which is the machining start depth, is read out from the machining information input in step 102, and is set as the initial depth Z. Next, the process moves to step 108, in which the intersection line calculation means calculates the intersection line between the plane and the curved surface at the depth Zl:. Next, the process moves to step 110, and it is determined whether the intersection line calculated in step 108 exists. If there is a line of intersection in step 110, the determination is YES, and the process moves to step 112, where an offset line of intersection is calculated from the line of intersection calculated in step 108, which is offset inward by the tool radius of the drill, which is the tool for drilling. do. Next, the process moves to step 114 for achieving a plunge point determination means, where the plunge point (X, Y coordinates) is read from the machining information input in step 102, and its position is the offset intersection line of the drill calculated in step 112. It is determined whether or not the current state is within a closed loop. In step 114, if the plunge point is within the offset intersection line of the drill, the determination is YES, and the process moves to step 116 to achieve the cutting NC data generation means, and step 10
An offset intersection line is calculated by offsetting the intersection line calculated in step 8 by the tool radius of the end mill, which is a cutting tool, and the plunge point, step width, etc. are calculated from the offset intersection line and the tool information and machining information input in step 102. Then, as shown in FIG. 5(C), NC data of cutting by an end mill, which is a cutting tool, is generated according to a spiral tool path so as to widen a hole drilled with a drill. Then, the process moves to step 118, and the machining end depth EZ (end 2
m) is read out, and it is determined in step 108 whether the depth Z calculated from the intersection line is less than or equal to EZ. If the machining depth Z is not less than EZ in step 118, the determination is NO, and the process moves to step 120, and step 10
From the tool information input in step 2, read out DZ, which is the increment amount of the end mill that is the cutting tool, and set the depth Z of the intersection line calculation to be deeper by the increment amount, Z = Z + DZ. Return to step 108, and the following steps are the same as above. Execute the process. Then, when the depth Z is less than Ez and the determination is YES in step 118, when there is no intersection line and the determination is NO in step 110, and in step 114, the plunge point is within the offset intersection line of the drill. It's not there, so the judgment is NO.
If so, the process moves to step 122. In step 122, the depth Z is made shallower by one increment.
=Z-DZ, and the process moves to step 124, which achieves the drilling NC data generation means, reads the plunge point, etc. from the tool information and machining information input in step 102, and performs the NC for drilling with a drill, which is a tool. Generate data. Then, the process moves to step 126, in which a drill, which is a tool, is first selected from the tool magazine 27 by the magazine indexing device in the enclosure and the tool changing device 28, and then
When the drilling of the workpiece W is finished, the drill is returned to the tool magazine 27. Next, an end mill, which is a cutting tool, is called from the tool magazine 27 and installed on the spindle 26, and then the rough cutting of the workpiece W is carried out. This program is completed by adding a tool change cycle such as the following. Note that EZ (end Z coordinate), which is the machining end depth that is preset and stored in the machining information of the present invention, is a value that is considered to be sufficiently deeper than the deepest Z coordinate of the female three-dimensional shape that is the finished shape. Enter. After each piece of NC data is generated as described above, Figure 5 (a) shows the operation of the NC data when each piece of NC data is connected and executed as a single piece of NC data in continuous rough machining. The explanation will be based on (C). First, as shown in FIG. 5(a), according to the NC data for drilling, a hole is drilled to a depth Z9 at which the insertion point can be inserted into the female three-dimensional shape. Next, as shown in Figure 5), the drill is replaced with an end mill based on the NC data for tool replacement. Then, as shown in Fig. 5 (C), according to the cutting NC data, the end mill performs rough machining using a uniform spiral spiral cutting process from SZ to the depth Z7 of the hole drilled with the drill in step widths and increments of ff1DZ. Execute at. In this way, by simply inputting the female three-dimensional shape of the finished shape, the hole can be drilled to its maximum depth, and the rough machining is performed by cutting to the same depth. Therefore, NC data for rough cutting is generated that does not leave a large machining allowance near the bottom of the female mold 3D shape even if the operator does not judge the depth of the finished female mold 3D shape. We can provide an NC data creation device that can.

【Effect of the invention】

The present invention provides a curved surface generating means for creating a curved surface from a female three-dimensional shape stored in a finishing shape memory means, and a curved surface for each increment amount from the created curved surface and a machining start depth stored in a machining condition memory means. Intersection line calculating means for calculating the line of intersection with the plane, and an offset line of intersection obtained by offsetting the calculated line of intersection and the diameter of the tool from the calculated line of intersection and the tool radius stored in the machining condition storage means. and a plunge point determining means that calculates the closed loop and the positional relationship between the plunge point of the tool and the plunge point of the tool. An offset intersection line that is offset by the tool radius is calculated from the intersection line calculated by the intersection line calculation means and the diameter of the cutting tool stored in the machining condition storage means, and the offset intersection line of the cutting tool and the above-mentioned machining condition storage are calculated. cutting NC data generation means for generating NC data of cutting by the cutting tool according to the tool path based on information stored in the means; ,
The drilling stored in the machining condition storage means is based on the information stored in the machining condition storage means from the plane depth calculated by the intersection line calculation means to the plane depth one quantum step before. Since it is equipped with a drilling NC data generation means that generates NC data, drilling is performed using a tool using the NC data generated by the drilling NC data generator stage to create a female three-dimensional shape that is the finished shape of the workpiece. After drilling a hole up to the very edge of the bottom of the shape, using the NC data generated by the cutting NC data generation means, the hole in the female three-dimensional shape can be rough-cut up to the position using a cutting tool. This has the effect that a large amount of machining allowance does not remain on the bottom surface of the female three-dimensional shape.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the concept of the present invention. FIG. 2 is a configuration diagram showing the configuration of a numerical control device and a machine tool having an NC data creation device according to a specific embodiment of the present invention. Figure 3 shows the MP used in the same embodiment device.
Flowchart showing the processing procedure of U12a. Figure 4 (
a) and FIG. 4, 6) are explanatory diagrams showing tool information and machining information according to the same embodiment. FIGS. 5(a) to 5(C) are explanatory diagrams showing a series of operations based on NC data of continuous pre-preparation processing created by the NC data creation device according to the same embodiment. 5 Workpiece table SM--Spindle motor W-1 Workpiece

Claims (1)

[Scope of Claims] An apparatus for creating NC data for a machine tool that rough-cuts a female three-dimensional shape according to a tool path using a cutting tool based on the position of a hole drilled in a workpiece to be machined using a drilling tool, Finished shape memory means for storing a female three-dimensional shape that is the finished shape of the workpiece; the diameter of the drilling and cutting tool, the increment amount that is a predetermined unit depth of penetration of the cutting tool into the material of the workpiece, etc. a machining condition storage means for storing machining information such as tool information, a plunge point set in advance for the workpiece of the drilling and cutting tool, and a machining start depth; and a knife stored in the finishing shape memory means. A curved surface generating means for creating a curved surface from the three-dimensional shape of the mold, and calculating an intersection line between the curved surface created by the curved surface generating means and a plane for each increment amount from a machining start depth stored in the machining condition storage means. an intersection line calculation means; calculating an offset line of intersection offset by a tool radius of the drilling tool from the intersection line calculated by the intersection line calculation means and the diameter of the drilling tool stored in the processing condition storage means; plunging point determining means for determining the positional relationship between the closed loop of the hole and the plunging point of the drilling tool; and when the plunging point determining means determines that the plunging point of the drilling tool is within the closed loop, the intersection line calculation means; calculate an offset intersection line offset by the tool radius from the intersection line calculated in and the diameter of the cutting tool stored in the processing condition storage means, and store the offset intersection line of the cutting tool and the cutting tool diameter in the processing condition storage means. cutting NC data generation means for generating NC data of cutting by the cutting tool according to the tool path based on the tool path; and when the penetration point determination means determines that the penetration point of the drilling tool is outside the closed loop; Drilling NC data for generating NC data for drilling by the drilling tool based on information stored in the machining condition storage means from the plane depth calculated by the intersection calculation means to the plane depth one increment before. An NC data creation device characterized by comprising a generation means.