JPS63207537A - Automatic processor for contouring form region in machine tool - Google Patents

Abstract

PURPOSE:To handle any interference of a tool path within the machining program, by installing an interfering part detector, detecting an interfering part from an intersection point between two elements of the calculated comparing form and the tool path, and a noninterfering NC data originating circuit converting the tool path of the interfering part into a noninterfering tool path. CONSTITUTION:A comparing form originating circuit 5 applies size and shift reference value of a working tool to pocket form element data for a work subject, and it calculates a closed region along the contour of a pocket. A tool path originating circuit 6 gives a direction to the pocket form element data and calculates the closed region of the tool path at each shift. An interfering part detector 7 calculates an interfering part from an intersection point between two elements of the calculated comparing form and the tool path. At the time of machining, a noninterfering tool path, leaving finishing allowance behind along the contouring form, is formed, and when the intersection of the tool path is caused in the midway of shifting a cutter in consecutive order, it is made to run till it is intersected with the noninterfering tool path on an extension line of the tool path, and afterward, it is made to run on the noninterfering tool path.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for automatically creating a machining program for a contoured region such as a pocket in a machine tool.

[Conventional technology]

It is no exaggeration to say that almost all machine tools in recent years are numerically controlled, and work is carried out according to machining programs according to each machining method and machining area. When creating a machining program, as shown in FIG. 10, an offset tool trajectory C■1. in which the cutter is sequentially shifted inward based on the pocket contour CVA is created. CV2I...
Some were programmed with CVn.

[Problem that the invention seeks to solve]

However, in the conventional method, the contour shape of the pocket is
For example, as shown in Fig. 10, in the case of a gourd shape, as the shift moves toward the final stage, the tool path CVn enters a region S where the outer peripheral wall on the opposite side is cut, so some kind of countermeasure is required. I'm coming.

Conventionally, as a countermeasure for this, when the tool path CVn reaches a position P where it intersects, the next intersecting position P2 that does not cut the outer peripheral wall is set.
It was common to program the robot to move in a straight line until the end. However, in the conventional method, the tool path CV
+ , CV 2 , ...CVn, it is necessary to judge whether they intersect each other, and then calculate the shortest path P I'' P t in which the work does not interfere with each of the intersecting tool trajectories. This required complicated calculations and was a huge hassle.

The present invention was proposed in view of these circumstances, and
It is an object of the present invention to provide an automatic contour region processing device that processes tool trajectory interference within a machining program without performing complicated calculations.

[Means for solving problems]

In the present invention, the measures taken to solve the above problems are provided in an automatic contour area processing device that creates a machining program along the contour of the pocket when machining the pocket shape with a machine tool. , a comparison shape creation circuit that applies the dimensions of the tool used and the shift reference amount to the pocket shape element data to be machined and calculates a closed area that follows the contour of the pocket, and a comparison shape creation circuit that gives direction to the pocket shape element data and a tool path creation circuit that calculates a closed region of the tool path; an interference part detection circuit that detects an interfering part from the intersection of both elements of the calculated comparison shape and the tool path; The present invention is an automatic contour region processing device equipped with a non-interfering NC data creation circuit for converting into a trajectory.

[Effect]

In the present invention, a non-interference tool path is formed that leaves a finishing allowance along the contour shape, and when the tool paths intersect while sequentially shifting the cutter, the non-interference tool path is formed on the extension line of the tool path. The tool is run until it intersects the tool path, and then the non-interfering tool path is run.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing an example of the configuration of an automatic contour region processing apparatus embodying the present invention.

In FIG. 1, the contour shape region automatic processing device is a CPU
I, display 2 with keyboard and its capo
) 2a, a tool reference table memory 3 that stores tool diameters and shift reference amounts for each tool used, a pocket shape memory 4 that stores pocket shape element data to be processed, a comparison shape creation circuit 5, and its calculation results. a comparison shape memory 5a that temporarily stores a tool path creation circuit 6 and its calculation results, a tool path memory 6a that temporarily stores a tool path creation circuit 6 and its calculation results, and an interference portion that detects an interference portion from the intersection of both elements of the calculated comparison shape and tool path. It is composed of a detection circuit 7, a non-interference NC data creation circuit 8 that converts the tool trajectory of the interference portion into a non-interference tool trajectory, and a non-interference NC data memory 8a that stores the created non-interference NC data. .

FIG. 2 is a flowchart showing an example of the operating procedure of the above device. In FIG. 2, the second stage of the flow is the input of the pocket shape, the 0th stage of the flow is the creation of the comparison shape based on the pocket shape element data in the comparison shape creation circuit 5, and the 0th stage of the flow is the input of the pocket shape. The tool trajectory creation circuit 6 creates an offset tool trajectory based on the pocket shape element data, and the 0th stage of the flow is the detection of an interference portion by comparing the comparison shape and the tool trajectory in the interference portion detection circuit 7. The 0th stage is the creation of non-interference NC data in the non-interference NC data creation circuit 8.

Below, stages (1) to (2) of the flow will be explained in more detail. FIGS. 3 to 5 are flowcharts showing in detail the operation contents of stage 1, stage 2, stage 2, and stage 0 of the above flow, and FIGS. FIG. 2 is an explanatory diagram showing a target shape and trajectory. 6th
In the figures to FIG. 8, the shape elements are taken as an example of the outer contour of pocket machining, the tool locus is assumed to shift from the outer contour to the inner side, and for convenience of explanation, all the elements are shown as straight lines. Moreover, the cutting direction was set counterclockwise.

FIG. 3 is a flowchart showing an example of a comparison shape creation procedure. Here, the comparison shape refers to a shape to be compared that allows the tool trajectory to be brought closest to the outer contour shape of pocket machining without cutting it. FIG. 6 is an explanatory diagram showing the relationship between the pocket shape and the comparative shape, and the outer contour shape CVA of the pocket is composed of a plurality of shape elements CVA+, CV^
2-CVAm, and the comparison shape CVA' has an element CVAI・C spaced inside thereof by a predetermined shift reference amount α.
VAz...CVAm' is formed. The shift reference amount α is stored as the shift amount A in the tool reference table memory 3, and as shown in FIG.
Finishing allowance k and interference prevention clearance (parameter)
This is the sum of p.

In the flow shown in FIG. 3, first, the overall direction is determined from each pocket shape element. The one with the largest Y value at the end point, for example the first
Find the angle between CVn in Figure 1 and the element following it, that is, the one with the maximum Y value at the end point (CVn+1 in Figure 11), with the X axis, assuming the counterclockwise direction is positive, and let θn and θn+l, then θn〈 If θn+1, the overall direction is counterclockwise, θ
If n>θn+l, it can be determined that the direction is clockwise.

For example, if the orientation of the shape in Figure 6 is determined using this method, the element whose end point is the maximum of Y is CVA, and the following element is CVA.
V A +, and the angle each makes with the X axis is θA2
．． If θA, then from Fig. 6, θA2#135°,
It can be determined that θA, #180°, and the direction of the shape is counterclockwise. Next, this orientation is compared with the cutting direction, and if they match, the orientation and order of all elements are rearranged, and converted to a non-matching direction (clockwise) for reasons described later.

Next, the pocket shape elements are shifted toward the center one element at a time by the reference amount α (offsera) (CVA, -CVAI・-
CVAm-CVAm'). The cono offset is easily calculated using the included angle and distance from the origin to the straight line segment of each shape element. However, based on only the calculation result, the length of the straight line segment remains the same and each element is different, so the intersection of one offset element and the next offset element is found and this is set as the end point of the element. For example, element CVAm' and element C
The intersection of VAI・ is Pm element CVA,・ and element CVA
The intersection of 2 and 2 is p+z, and when the end point calculations for all elements are completed, a closed region of the comparison shape is formed a distance α inside from the pocket shape. The flow ends by writing the closed region into the comparison shape memory 5a.

FIG. 4 is a flowchart showing an example of a tool trajectory creation procedure. In this flow, first input the pocket-shaped closed regions calculated in the comparison shape creation procedure, rearrange the orientation and order of the closed regions to match the cutting direction, and then
The pocket shape elements are offset one by one toward the center by a predetermined shift reference amount β, and tool path elements CVII, CV21...CVn as shown in FIG. 7 are created.
, get . The shift reference amount β is stored as the shift amount B in the tool reference table memory 3, and is the sum of the tool radius, the finishing allowance, and the remaining amount of the contour portion. This offset is also easily calculated in the same way as in the comparison shape creation procedure,
By finding the intersection points of the elements, a closed region of a multi-stage tool trajectory is formed. The flow ends by writing the closed area into the tool path memory 6a.

Now, with this tool path, as is clear from Figure 7,
Interference occurs in areas S and S'.

Therefore, it is necessary to detect the interference portion and create a non-interference tool trajectory using the flow shown in FIG. First, select one element (CVnm) of the tool path from the tool path memory 6a.
The comparison shape corresponding to the tool path element is read as 1.
Read each element (CVAm') and find the intersection of the two. If the existence of an intersection is discovered, this is the detection of an interfering part, and the tool path element and comparison shape element that have the intersection between the start point and the end point are searched, and the intersection data of those two elements and the intersection is calculated. Store coordinate values. Then, by continuing to search for an intersection point on the same tool trajectory, if the existence of a pair of intersection points is discovered, this is the detection of the second interference part (interference escape part), so the intersection data is created and the second intersection point is detected. As shown in Fig. 8, from the first intersection point P,・ to the second intersection point P2・, the tool trajectory CVn does not adopt the tool trajectory element, but adopts the comparison shape element, and creates a non-interfering tool trajectory. Create non-interference NC data to pass through CVn''. At this time, the direction of the closed region is reversed in this section, so when creating the procedure, the direction of the comparison shape closed region is set opposite to the cutting direction. When all the elements have been examined, the flow ends by writing the completed non-interference NC data into the non-interference NC data memory 8a.

In addition, in the case of machining to form a mountain in the pocket, as shown in FIG. Processing similar to the flow shown in can be performed.

When performing machining, non-interfering NC data should be
By simply dropping the tool from the C data memory 8a onto the tape, the tool will automatically run avoiding the interference area.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide an automatic contour region processing device that processes tool trajectory interference within a machining program without performing complicated calculations each time.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of one embodiment of the present invention, Figs. 2 to 5 are flowcharts of the operating procedure of the embodiment, Figs. 6 to 9 and 11 are explanatory diagrams of shape elements, and Figs. FIG. 10 is an explanatory diagram of a conventional tool trajectory. 1.CPU. 2; Display with keyboard, 3; Tool reference table memory, 4; Pocket shape memory, 5; Comparison shape creation circuit, 6; Tool trajectory creation circuit, 7; Interference portion detection circuit, 8; Non-interference NC data creation circuit, CVAi Contour shape CV8", cVB'i comparison shape, CVn: tool path, CVn": non-interference tool path.

Claims (1)

[Claims] When machining a pocket shape with a machine tool, the automatic contour area processing device that creates a machining program that follows the contour of the pocket uses the dimensions of the tool used and the shift reference amount in the pocket shape element data to be machined. A comparative shape creation circuit that calculates a closed region along the contour of the pocket, and a direction given to the pocket shape element data.
A tool path creation circuit that calculates the closed area of the tool path for each shift, an interference part detection circuit that detects the interference part from the intersection of both elements of the calculated comparison shape and the tool path, and an interference part detection circuit that detects the tool path of the interference part. Non-interference NC converting to interference tool path
1. An automatic processing device for contour shape regions in a machine tool, characterized by comprising a data creation circuit.