JPH07100261B2 - Wire EDM method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a wire electric discharge machining method of interrupting a shape machining and skipping to the next shape machining when a defect occurs during the shape machining execution. is there.

[Conventional technology]

FIG. 4 is a configuration diagram showing a conventional wire electric discharge machining apparatus. In the figure, (1) is a workpiece, (2) is a movable table on which the workpiece (1) is mounted and fixed, and (3) is A machine body of a wire electric discharge machine, (4) is a wire electrode for machining a work piece (1), and (5) is a machining liquid for the work piece (1).
A machining fluid supply device for supplying a machining gap formed between the wire electrodes (4) of the machine, and (6) for position control, machining control in the machine body (3) or automatic disconnection recovery operation of the wire electrodes (4). Numerical control device (hereinafter referred to as NC device) for executing control, (7) is a wire electrode automatic supply device for automatically connecting or disconnecting the wire electrode (4),
Reference numeral (8) is a machining power supply device for supplying a discharge current to a machining gap formed between the wire electrode (4) and the workpiece (1).

FIG. 5 is an internal control block diagram showing the detailed configuration of the NC device. In the figure, (9) is an NC for controlling the machine body.
Program, (10) is a program analysis section that executes the analysis of NC program (9), (11) is a machining fluid supply device (5)
By controlling the machining fluid, a machining fluid control unit that supplies the machining fluid to the machining gap, and (12) automatically controls the wire electrode automatic feeder (7) to automatically connect or disconnect the wire electrode (4). Automatic supply control unit,
(13) is a wire control unit that outputs a wire electrode (4) supply control signal or a disconnection signal, and (14) is a machining fluid control unit (1).
1), a mechanism input / output unit for exchanging signals with the automatic supply control unit (12) and the wire control unit (13), and (15) is a servo motor (16) based on a signal from the program analysis unit (10). ) Is driven to control the position of the movable table (2), and the machining liquid control unit (11), the automatic supply control unit (12), and the wire control unit (13) are also passed through the machine input / output unit (14).
To control the machining liquid, the wire electrode (4) or machining, and based on the disconnection signal of the wire electrode (4) from the wire controller (13), the wire electrode (4) (17) is a display unit that displays data such as coordinates on the CRT (18) screen, and (19) is a disconnection of the wire electrode (4) being processed. When skipping to the next shape processing due to reasons such as
6 is a machining skip data storage table in which machining start hole coordinates or machining start hole numbers, which are machining start position data of a shape machining that has become impossible to machine, are stored via a control unit (15). The machining skip operation is entirely controlled by the control section (12).

FIG. 6 is a view for explaining a processing state in the case where two shape processings are combined to generate one shape-processed object from a workpiece, in which (a) is internal shape processing,
(B) is an external shape processing, (A) is a processing start hole of internal shape processing (a), (B) is a processing start hole of external shape processing (b).

FIG. 7 is a diagram showing an NC program for executing the shape machining shown in FIG. 6, in which (20) is a main program and (21) is for performing internal shape machining (a). The subprogram (22) is a subprogram for executing the machining of the external shape machining (b).

FIG. 8 is a flow chart showing the internal processing of the processing skip.

Next, the operation will be described. As shown in FIG. 4, the work piece (1) mounted and fixed on the movable table (2) is NC.
While the position is controlled by the device (6), the operation according to the NC program (9) analyzed by the program analysis unit (10) is performed. Further, the wire electrode (4), the machining liquid supply device (5), etc. are connected to the control section (1) via the machine input / output section (14).
5) controlled by. Then, the machining liquid supplied from the machining liquid supply device (5) is used as an electric discharge medium, and the workpiece (1) is electric discharge machined by the machining current supplied from the machining power supply device (8). The processing information such as the position of the movable table (2) is displayed on the CRT (18) screen by the display controller (17).

Next, the case of processing the shape as shown in FIG. 6 will be described.

When the main program (20) is started as shown in FIG. 7 by starting the NC device (6), the main program (20)
The subprogram (21), that is, "L100" is read by the instruction of "G22L100" in the subprogram (21)
, The wire electrode (4) is automatically connected by the wire electrode automatic supply device (7) at the processing start point (A), and then the inner shape processing (a) is executed, and then the processing is completed. At the point, the wire electrode (4) is automatically cut by the wire electrode automatic feeder (7).

When the execution of the subprogram (21) is completed as described above,
Returning to the main program (20) again, the command (G00Y-10. "Is executed. By this command, the wire electrode (4) is Y.
Move the shaft in the minus direction by 10 mm to process the outer shape (b)
Is positioned at the machining start point (B).

Next, execute the subprogram (22) by the command of "G22L200".
That is, "L200" is read out and the subprogram (2
According to the command of 2), first, the wire electrode (4) is automatically connected by the wire electrode automatic supply device (7) at the processing start point (B), and then the outer shape processing (b) is executed. The wire electrode (4) is automatically cut by the wire electrode automatic supply device (7) at the processing end point.

Through the process described above, the shape shown by the diagonal lines in FIG. 6 is generated by the inside shape processing (a) and the outside shape processing (b).

Incidentally, during each of the above-mentioned processing, as shown in FIG. 8, a process for judging whether or not the processing can be continued is executed. That is, in step (23), it is determined whether or not the shape machining is performed according to the NC program. If the shape processing is performed, it is always determined in step (24) whether or not there is a problem such as a wire electrode (4) disconnection during the shape processing or a short circuit with the workpiece (1). If the above problem does not occur, step (25)
As shown in (1), the shape processing is continued, and when the above-mentioned trouble occurs, it is judged that the shape processing is impossible, and the process proceeds to step (26). In step (26),
Processing skip data storage table (19) shown in FIG.
The machining start position coordinates of the above-mentioned shape machining that cannot be machined, machining skip data such as the machining start hole number, or the machining start hole number, are stored, and after the shape machining is stopped, the next shape machining is performed. The movable table (2) is moved so that the wire electrode (4) moves to the processing start hole position, and the next shape processing is continued.

In addition, the machining skip data stored in the machining skip data storage table (19) is displayed on the CRT (18) screen,
It is designed to call the operator's attention.

[Problems to be Solved by the Invention]

Since the conventional wire electric discharge machining method is performed as described above, as shown in FIG. 6, during the inner shape machining (a),
At the point (c), wire breakage of the wire electrode (4) or a short circuit frequently occurs between the workpiece (1) and the wire electrode (4), and the machining is skipped by the process of step (26) shown in FIG. Outside shape processing that is the next processing target (b)
Is processed, the outer shape processing (b) is separated from the workpiece (1), and the inner shape processing (a) cannot be processed later, and the shape according to the program is obtained. There was a problem to be solved such as not being able to solve it.

The present invention has been made to solve the above problems, and an object thereof is to obtain a wire electric discharge machining method in which machining errors do not occur in machining composed of a combination of a plurality of shape machining.

In the wire electric discharge machining method according to the present invention, electric discharge is generated between a wire electrode and a workpiece, the wire electrode is moved relative to the workpiece, and the workpiece is continuously subjected to shape machining. In the wire electric discharge machining method, a step of interrupting the first shape machining in which a defect has occurred and storing the first shape machining data, and referring to the stored data, transition to the second shape machining is performed. There is a step of judging whether or not it is possible and storing the result, and a step of referring to the stored judgment result, and only when the above judgment result can shift to the second shape machining. Then, the second shape processing is performed.

[Operation] In the present invention, whether or not the next second shape processing is processed on the condition that the interrupted first shape processing is completed when the first shape processing having a defect is interrupted It is determined whether or not the wire electrode is moved to the start position of the second shape processing only when the determination result does not require the completion of the first shape processing. When the completion of the processing is a condition, the second shape processing is not performed.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a flow chart for explaining one embodiment of the present invention, and FIG. 2 is a diagram showing an NC program for executing a machining method according to one embodiment of the present invention. In the figure,
(32) is a main program for executing the subprograms (21), (22). Since the subprograms (21) and (22) are the same as those shown in FIG. 7 of the conventional example, the description thereof will be omitted.

Next, the operation will be described. It should be noted that the description of the operation overlapping with that of the conventional example is omitted. When the main program (32) is started by the start of the NC device (6) as shown in Fig. 2, the sub program (21), that is, "L100" is read by the instruction of "G22L100" in the main program (32). Issued, and the third by the instruction of the subprogram (21)
As shown in the figure, first, the wire electrode (4) is automatically connected by the wire electrode automatic supply device (7) at the processing start point (A), and then the inner shape processing (a) is executed.
During this period, as in the conventional example, it is constantly monitored by the flow shown in FIG. 8 whether or not the processing can be continued.

Here, for example, as shown in FIG. 3, inner shape processing (a)
When the wire electrode (4) is disconnected or the work piece (1) is short-circuited at a point C during the machining, it is determined that the machining cannot be continued according to the flowchart shown in FIG. The control section (15) shown in FIG. 5 executes the machining skip of the inner shape machining (a), and the machining start hole coordinates or the machining start which is the data at the machining start position in the machining skip data storage table (19). The hole number and the like are stored.

Next, as shown in step (40) of the flow chart of FIG. 1, when the subprogram (21) is interrupted, the wire electrode automatic feeder (7) is operated to remove the wire electrode (4) at the point (c). After cutting, the remaining paths of the sub program (21) are not processed, and as shown in step (41), the process returns to the main program (32) and the next NC command "G14X
50Y1 ”is executed. That is, first, as shown in step (42), the content search of the processing skip data storage table (19) is executed, and subsequently, as shown in step (43),
By the command "Y1" that executes the inspection of the machining shape in the previous stage,
The processing start point number of the inner shape processing (a) (hereinafter, referred to as "1") is read. Subsequently, in step (44), it is determined whether or not there is a processing start point number "1" of the former stage shape processing. If not, a series of processing is continued as shown in step (45). If there is (in this case, the machining start point number "1"), in step (46), a command is issued to determine whether or not the completion of the machining of the machining start point number "1" is a condition for the next stage machining. By this command, the determination is executed in step (47). Here, if the completion of the shape machining of the machining start point number "1" is not the condition of the next shape machining, as shown in step (48), "X50" of the main program (32) Set "0" as the return value of the inspection result in the variable reading area specified by. If the completion of the shape machining of the machining start point number “1” is the condition for the next shape machining, as shown in step (49), “X50” of the main program (32)
Set "1" as the return value of the inspection result in the variable reading area specified by. As a result, information of "0" and "1" is stored in the variable reading area "X50" as shown in step (50).

Then, the NC command "G203A1BH50C1" is executed. This process is executed as follows in step (51). First, the contents of the variable reading area "X50" are read into "BH50". Next, in step (52), the content is judged by the instruction "C1". That is, when the content of the instruction “C1” is “1” and the content of the above “BH50” is “1”, the next NC instruction “G00Y-10.” Is not executed and the step (53) is executed. As shown, jump to execution of NC program "N1" commanded by instruction "A1".
If the content "BH50" is "0" for the content "1" of the instruction "C1", as shown in the next step (54), the next NC instruction "G00Y-10." That is, the subprogram (22) is executed.

As described above, when a machining skip occurs during execution of the subprogram (21), it is determined whether the shape machining at the skip destination is to be machined under the condition that the previous shape machining is completed. Therefore, in the case of the shape as shown in FIG. 3, the subprogram (22) is not executed, and it is possible to prevent a processing error in the shape processing. Further, if the shape processing of the skip destination is not a condition for the completion of the former shape processing, the processing is continuously executed.

In the above embodiment, one shape is described for the sake of simplicity, but it goes without saying that the same effect can be obtained when another shape and a plurality of shapes are continuously machined by a series of NC programs.

[Advantages of the Invention] As described above, according to the present invention, the first failure
Interrupting the second shape processing, determining whether the next second shape processing is to be processed on the condition that the interrupted first shape processing is completed, and the determination result is The step of moving the wire electrode to the start position of the second shape processing only when the completion of the shape processing of No. 1 is provided, so that processing including a combination of a plurality of shape processings (for example, an inner shape If the outer shape cannot be machined unless the machining is completed, it is better not to machine the donut shape machining or the part left unmachined during rough shape machining during finish shape machining from the viewpoint of machining accuracy. There is an effect that a processing error does not occur in the shape processing and the finish shape processing.

[Brief description of drawings]

FIG. 1 is a flow chart for explaining the operation of the wire electric discharge machining method according to one embodiment of the present invention, and FIG. 2 is a flow chart for realizing the wire electric discharge machining method according to one embodiment of the present invention.
FIG. 3 is a diagram showing an NC program, FIG. 3 is a diagram for explaining shape machining according to an embodiment of the present invention, FIG. 4 is a configuration diagram showing a configuration of a conventional wire electric discharge machining apparatus, and FIG. FIG. 6 is an internal control block diagram showing the details of the NC device used in the wire electric discharge machining device, and FIG. 6 is for explaining a machining state in the case of combining two conventional shape machining products to generate one shape machining product from a workpiece. FIG. 7, FIG. 7 is a diagram showing an NC program for executing the shape machining shown in FIG. 6, and FIG. 8 is a flowchart showing a conventional machining skip internal process. In the figure, (40) is the step for interrupting the subprogram, (46) is the step for determining whether the completion of the previous-stage shape machining is the condition for the next-stage shape processing, and (52) is the next-stage shape processing. This is a step of determining whether to perform the predetermined shape processing. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. A wire electric discharge machining method, wherein electric discharge is generated between a wire electrode and a workpiece, the wire electrode is moved relative to the workpiece, and the workpiece is continuously machined. , The step of storing the first shape machining data while interrupting the first shape machining in which the defect has occurred, and referring to the stored data to determine whether or not the transition to the second shape machining is possible. There is a step of making a judgment and storing the result, and a step of referring to the stored judgment result. Only when the judgment result can shift to the second shape machining, A wire electric discharge machining method, characterized in that the method shifts to shape machining.