JP2009233842A - Wire electric discharge machining method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wire electric discharge machining method which improves the straightness of a workpiece in its through-thickness direction by the oscillation machining of the workpiece. <P>SOLUTION: The wire electric discharge machining method oscillation-machines the workpiece 2 with respect to a machining advancement direction for the electric discharge machining of the workpiece 2 into a predetermined machining shape which is decided beforehand by oscillation-advancing a wire electrode 1 or the workpiece 2 obliquely to the machining advancement direction by a predetermined width, thereby improving the accuracy of finishing in the straightness of the workpiece 2 in the through-thickness direction. This wire electric discharge machining method performs appropriate oscillation machining only without changing machining conditions, thereby achieving electric discharge machining stably at a high degree of accuracy without reduction in machining speed. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a wire electric discharge machining method for electric discharge machining a workpiece by electric discharge energy generated by applying a machining voltage between a wire electrode and the workpiece.

  Conventionally, as shown in FIGS. 1 and 2, in a wire electric discharge machine, a Y-axis table 30 is provided on a bed 17 as a base so as to be movable in the Y-axis direction, and an X-axis table 31 is provided on the Y-axis table 30. Is provided so as to be movable in the X-axis direction. The head 33 in the machine body is provided with the upper wire head 3, and the lower arm 28 in the machine body is provided with the lower wire head 4. The upper wire head 3 has the wire electrode 1 formed on the workpiece 2. The lower wire head 4 functions to supply to the start hole 24 and the processing slit 36, and the lower wire head 4 functions to receive the wire electrode 1 after processing the workpiece 2 facing the lower side of the upper wire head 3. The wire electric discharge machine also guides the consumed wire electrode 1 that has been subjected to electric discharge machining from the lower wire head 4, so that the wire from the guide roller 5 and the guide roller 5 installed below the lower wire head 4 is used. A wire guide pipe 6 provided for feeding out the electrode 1 and a drawing roller 7 for drawing out the wire electrode 1 provided in the vicinity of the outlet of the wire guide pipe 6 are provided. The wire automatic supply device 9 in the wire electric discharge machine includes a source bobbin 37 around which the wire electrode 1 is wound up, a guide roller 20 that changes the direction of the wire electrode in the wire feed system that is fed from the source bobbin 37, and a direction change. A roller 22, a tension roller 19 that applies tension to the wire electrode 1 that is fed out, and a brake roller 29 that applies a brake so that the wire electrode 1 to which tension is applied are fed out satisfactorily. The wire electrode 1 that has passed through the direction changing roller 22 in the wire supply system passes through a pair of guide rollers and a pair of annealing rollers 10 that are wire electrode feed rollers provided in the head 33 and a pair of common rollers 11. A current from a machining power source is applied between them through a power supply, the wire electrode 1 is annealed, and then fed into the upper wire head 3. Further, a cutter 13 is provided between the annealing roller 10 and the common roller 11 to improve the tip of the wire electrode 1 or to cut the wire electrode 1 when the wire electrode 1 is disconnected. The wire electrode 1 that has passed through the upper wire head 3 is received by the lower wire head 4 facing the lower side of the upper wire head 3 after a machining voltage is applied to the workpiece 2 and the workpiece 2 is machined. Next, the consumed wire electrode 1 fed out from the lower wire head 4 is fed through a guide roller 5 to a jet guide pipe 6 provided with a discharge port 23 for discharging a jet at the outlet. The wire electrode 1 is sucked by a drawing roller 7 provided in the wake of the jet guide pipe 6 and a suction device provided in the wake of the drawing roller 7 and is finally collected in a waste wire hopper.

  Also, as a wire electric discharge machining apparatus, a device that prevents the occurrence of a drum shape peculiar to wire electric discharge machining and improves the machining accuracy in the straight direction and the machining accuracy in the corner portion is known. The wire electric discharge machining apparatus includes a machining power supply for supplying a discharge current, a voltage detection circuit for detecting an average voltage between discharge electrodes being machined, a current detection circuit for detecting an average current, and controlling the discharge voltage and the discharge current. When the machining feed rate is controlled so that the average voltage value is constant, the control device must set the discharge current off-time or pulse cycle so that the average current changes in inverse proportion to the machining feed rate. When the machining feed rate is controlled so that the average current value is constant, the control device controls the off time such as the discharge voltage or the pulse cycle so that the average voltage changes in proportion to the machining feed rate. Is. Further, in Patent Document 1, conventionally, in wire electric discharge machining, the straight direction of the work piece has a drum shape and the amount of bending changes depending on the thickness of the work plate and the processing conditions, and the straightness accuracy of the work piece in the straight direction is also disclosed. In general, in roughing (first cut), the workpiece has a drum shape, so high-precision finishing (second cut) must be performed after roughing. Is described. In order to solve these problems, the above-mentioned wire electric discharge machining apparatus controls the feed speed, average current, average voltage, etc., and thereby the discharge repulsive force generated by the discharge and the electrostatic attraction force between the wire electrode and the workpiece. And the wire electrode being processed is kept in a straight state to suppress the occurrence of a drum shape (for example, see Patent Document 1).

  In addition, a cutting method is known in which a wire and a workpiece are relatively moved when the workpiece is cut. The cutting method is such that a wire serving as one electrode and a workpiece serving as the other electrode are moved relative to each other according to a predetermined cutting path and a vibration motion in a direction perpendicular to the cutting path. The workpiece is cut by erosion electrical discharge machining, and the instantaneous amplitude of the variation perpendicular to the cutting path is controlled. When the instantaneous amplitude increases to the maximum value, the discharge energy is reduced to the minimum value. When the instantaneous amplitude decreases to the minimum value, the discharge energy is increased to the maximum value. In the above cutting method, when the wire and the workpiece are moved relative to each other, the magnitude of the amplitude and the strength of the discharge energy are controlled, and the finishing process is performed simultaneously with the cutting process. Time is shortened (for example, refer patent document 2).

  Further, as a wire electric discharge machining method, a method capable of simultaneously machining two surfaces with an arbitrary gap is known. The wire electric discharge machining method was set by adding an offset amount to the locus indicating the shape of each workpiece when machining by generating an intermittent discharge between the wire electrode and the workpiece in the machining fluid. Using two machining loci as the rocking ends, a rocking locus for periodically moving the machining position is set, and the wire electrode is moved along the rocking locus for machining. The axis of the existing machining section on the other machining trajectory from one machining trajectory in the direction intersecting the trajectory alternately moving on each machining trajectory and the trajectory indicating the shape of each work surface. It is set in the section to move to the last arrival position. That is, in the wire electric discharge machining method, the machining enlargement allowance can be remarkably increased as compared with the diameter dimension of the wire electrode by performing rocking machining (see, for example, Patent Document 3).

Further, the conventional wire electric discharge machining method is a method of machining a workpiece by generating an electric discharge between the electrode between the wire electrode and the workpiece, and includes a first step of performing electric discharge machining in a machining liquid, , Comprising a second step of performing electric discharge machining in mist and a third step of performing electric discharge machining in gas, and switching between the steps when the straightness of the workpiece reaches a predetermined value (For example, see Patent Document 4).
JP-A-5-8122 JP 58-186533 A Japanese Patent No. 2912416 WO02 / 000383 publication

  By the way, with a conventional wire electric discharge machine, in rough machining, that is, first cut, on a workpiece, in order to improve straightness accuracy, the electric repulsion force, electrostatic attraction, or jet flow received by the wire electrode is reduced. Needed to be extremely slow. In addition, as in the conventional patent document 1, the method of reducing the dimensional difference by detecting the inter-electrode state between the wire electrode and the workpiece and changing the feed rate, the average current, and the average voltage, Due to changes in the processing conditions for the workpiece, the control results changed, and it was considered difficult to obtain a dimensional difference stably, which was problematic. Therefore, as a wire electric discharge machining method, there is a problem of how to configure the electric discharge machining for a workpiece so as to improve the straightness accuracy and not to reduce the machining speed.

  The present applicant, when performing electric discharge machining on a wire electric discharge machine, performs electric discharge machining while giving a constant amplitude in a direction perpendicular to the traveling direction, and performs electric discharge machining while giving a constant circular motion to the wire electrode. The method, or the relative amplitude given to the workpiece or wire electrode, focused on the case of processing in the same phase up and down and the method of processing in the upside down phase, and the straightness accuracy in the first cut was reduced.

  An object of the present invention is to solve the above-described problems, and in a wire electric discharge machine, when performing electrical discharge machining of a workpiece, straightness accuracy is improved without extremely reducing the machining speed during rough machining, that is, first cutting. It is an object of the present invention to provide a wire electric discharge machining method characterized by being able to be improved.

According to the present invention, a wire electrode fed from a source bobbin drives a wire electrode feed roller to drive an upper wire head through a supply pipe, a workpiece installed below the upper wire head, and the upper wire below the workpiece. In a wire electric discharge machining method for supplying electric power to a lower wire head disposed opposite to the head and moving the workpiece relative to the wire electrode to electric discharge machining the workpiece,
The wire electrode or the workpiece is swung in the machining progress direction with a predetermined width with respect to a machining progress direction in which the workpiece is subjected to electric discharge machining into a predetermined machining shape, and the workpiece is shaken. The present invention relates to a wire electric discharge machining method characterized in that the machining accuracy of the straightness in the plate thickness direction of the workpiece is increased by dynamic machining.

  In this wire electric discharge machining method, the predetermined width for swinging the wire electrode or the workpiece in the machining progress direction is a swing width of 0.1 ± 0.02 mm in one dimension from the center in the progress direction. preferable. Moreover, it is preferable that the predetermined pitch which advances the said wire electrode or the said workpiece in a process advancing direction is 1 micrometer-10 micrometers. Further, the rocking process with a predetermined width in the machining progress direction can be achieved by causing the workpiece to swing and advance in an oblique, circular or square shape with respect to the machining progress direction.

  Further, in this wire electric discharge machining method, the rocking process on the workpiece is performed by applying vertical and in-phase vibrations to the workpiece in a direction perpendicular to the machining progress direction with respect to the wire electrode. Alternatively, the oscillating process on the workpiece is performed by applying an up / down antiphase vibration to the workpiece in a direction perpendicular to the machining progress direction with respect to the wire electrode.

  Further, in this wire electric discharge machining method, the upper phase vibration applied to the workpiece in a direction perpendicular to the machining progress direction with respect to the wire electrode in the swing machining with respect to the workpiece operates the U axis and the V axis. , Lower phase vibration is performed by operating the X axis and the Y axis.

  Further, in this wire electric discharge machining method, the drive device that operates the X-axis slide unit, the Y-axis slide unit, and the UV axis unit in the wire electric discharge machine that performs the swing machining on the workpiece increases the vibration speed. Therefore, it is preferable that there is a linear motor.

  In this wire electric discharge machining method, as described above, the wire electrode or the workpiece is swung with a predetermined width in the machining progress direction with respect to the machining progress direction in which the workpiece is subjected to the electric discharge machining in a predetermined machining shape. Therefore, the machining accuracy of straightness in the thickness direction of the workpiece can be improved. Further, in the conventional wire electric discharge machine, in order to improve the straightness, the machining conditions are changed by controlling the feed rate, the average current, and the average voltage. Since only machining is performed and the machining conditions are not changed, electric discharge machining can be achieved with high accuracy and stability. Further, in the conventional wire electric discharge machine, generally, after the rough machining (first cut) on the workpiece, the dimensional difference is reduced by finishing, that is, the second cut. The straightness is improved by oscillating machining, so there is no need to make a second cut, and the total machining time of EDM for the workpiece can be shortened. Furthermore, even if a second cut is made on the workpiece, the dimensional difference in straightness is small, so that the second cut machining time can be shortened.

  A wire electric discharge machine for achieving the wire electric discharge machining method according to the present invention will be described below with reference to the drawings. In this wire electric discharge machine, the processing tank 18 for preventing the scattering of the machining fluid is attached to the X-axis slide 31 by a fixing tool such as a bolt and a nut, for example. In this wire electric discharge machine, a bed 17 such as a machine base is installed on a floor of a factory, a base such as a base. In this wire electric discharge machine, the processing tank 18 and the processing tank 18 integrated with the X-axis slide 31 are placed and moved in a direction perpendicular to the moving direction (X-axis direction) of the processing tank 18 (Y-axis direction). Since the lower arm 28 penetrates relative to the relative movement of the Y-axis slide 30 and the processing tank 18 which are possible cross saddles, a shielding plate having a hole facing the long hole is provided. In this wire electric discharge machine, in order to perform wire electric discharge machining on the workpiece 2 in a predetermined machining shape, the wire electrode 1 is provided in a column 16 constituting the machine body from a source bobbin of a wire electrode supply source. It is supplied to the machining area of the workpiece 2 by an automatic wire feeder 9 provided with a guide roller 20 and the like. The wire electrode 1 applies a voltage between the workpiece 2 and processes the workpiece 2, and after the workpiece 2 is processed, the wire electrode 1 is collected through the waste wire passage of the lower arm 28. .

  The Y-axis slide 30 incorporated in the cross saddle is configured to reciprocate in the Y-axis direction with respect to the bed 17 via a Y-axis slide unit provided between the bed 17 and the Y-axis slide. Further, the X-axis slide 31 integrated with the processing tank 18 is arranged in the X-axis direction with respect to the Y-axis slide 30 of the cross saddle via an X-axis slide unit provided between the Y-axis slide 30 and the cross saddle. It is configured to reciprocate. In the X-axis slide unit, a plurality of sliders fixed to the X-axis slide 31 move relative to each other on a pair of track rails 34 fixed to the Y-axis slide 30, so that the processing tank 18 moves relative to the Y-axis slide 30. It reciprocates in the X axis direction. Further, the Y-axis slide unit moves the Y-axis slide 30 relative to the bed 17 by moving the plurality of sliders fixed to the Y-axis slide 30 on the pair of track rails 35 fixed to the bed 17. It reciprocates in the axial direction.

  This electric discharge machine is composed of a bed 17 constituting a base installed on a floor or a base, a column 16 constituting a main body of a machining machine erected from the bed 17, and a Y-axis slide unit reciprocating in the Y-axis direction on the bed 17. The Y-axis slide 30, the processing tank 18 configured integrally with the X-axis slide 31 that reciprocates in the X-axis direction on the Y-axis slide 30, the UV axis unit 32 provided on the column 16, and the UV axis unit Z-axis unit 12 provided in 32, upper wire head 3 provided in Z-axis unit 12, lower wire head 4 provided in lower arm 28 extending from column 16, and upper wire head 3 and lower wire head 4 The workpiece 2 installed in the machining tank 18 is provided. In this wire electric discharge machine, the workpiece 2 installed in the machining tank 18 is machined by the wire electrode 1 supplied from a wire electrode supply source (not shown) provided in the column 16, so that the workpiece 2 and the wire Electric discharge machining is performed by electric discharge energy generated by applying a machining voltage between the electrode 1 and the electrode 1. The wire electric discharge machine further includes a UV axis unit 32 provided on the upper part of the column 16 and a Z axis unit 12 provided on the UV axis unit 32 on the upper part of the column 16. On the other hand, it is possible to secure a wide machining area and perform high-precision machining.

  In this wire electric discharge machine, the wire electrode 1 extends laterally from the upper wire head 3 supported by the UV axis unit 32 attached to the column 16 and the long hole of the processing tank 18 from the column 32. It is guided by the lower wire head 4 supported by the lower arm 28. The upper wire head 3 incorporates a wire delivery port, a die guide, a jet nozzle, a feed electron, a feed electron presser, and the like as in the prior art, and feeds the wire electrode 1 to an electric discharge machining portion of the workpiece 2. The lower wire head 4 incorporating the power supply has the same structure as the upper wire head 3, is provided at a position facing the upper wire head 3, and is a wire electrode fed from the upper wire head 3. Accept 1 A lead wire connects the power supply of the upper wire head 3 and the power supply of the lower wire head 4, and the lead wire is given a pole opposite to the pole connected to the lead wire. After the wire electrode 1 that has been subjected to electric discharge machining on the workpiece 2 is received by the lower wire head 4, the wire electrode 1 is drawn by the drawing roller 7 from the machining tank 18 through the waste wire passage inside the lower arm 28 through the guide roller. And discharged to the outside.

  This wire electric discharge machining method can be achieved by using the above-mentioned wire electric discharge machine, and in particular, the electric discharge machining is performed by relatively moving the wire electrode 1 and the workpiece 2. The workpiece 2 or the wire electrode 1 is oscillated obliquely with a predetermined width in the processing advance direction relative to the progress direction in which the predetermined shape is determined by electric discharge machining. The processing accuracy of straightness in the thickness direction of the object 2 is improved. In this embodiment, the workpiece 2 is swung with respect to the wire electrode 1 using the X-axis slide 31 of the X-axis slide unit and the Y-axis slide 30 of the Y-axis slide unit, and the wire electrode 1 is moved to the workpiece. 2 is swung using the UV axis unit 32.

  In this wire electric discharge machining method, the predetermined width for swinging the wire electrode 1 or the workpiece 2 in the machining progress direction is straightly set to be a swing width of 0.1 ± 0.02 mm in one side dimension from the center in the progress direction. The degree can be increased, which is preferable. Further, in this wire electric discharge machining method, the workpiece 2 is oscillated in an oblique zigzag manner in the machining progression direction with respect to the wire electrode 1 and the workpiece 2 is subjected to electric discharge machining. At this time, it is preferable that the predetermined pitch for moving the wire electrode 1 or the workpiece 2 in the machining progress direction is 1 μm because the straightness can be increased.

  Further, in this wire electric discharge machining method, the electric discharge oscillating machining for the workpiece 2 is performed by giving the workpiece 2 vertical and in-phase vibrations perpendicular to the machining progress direction with respect to the wire electrode 1. Alternatively, the electric discharge oscillating process on the workpiece 2 is performed by applying an up / down antiphase vibration to the workpiece 2 in a direction perpendicular to the machining progress direction with respect to the wire electrode 1. Furthermore, in this wire electric discharge machining method, the upper phase vibration applied to the workpiece 2 in the direction perpendicular to the machining progress direction with respect to the wire electrode 1 in the electric discharge oscillation machining for the workpiece 2 operates the UV axis unit 32, The side phase vibration is performed by operating the X-axis slide 31 of the X-axis slide unit and the Y-axis slide 30 of the Y-axis slide unit.

  Next, with reference to FIG. 3 to FIG. 7, a state in which the workpiece 2 is subjected to electric discharge machining with the wire electrode 1 by this wire electric discharge machining method will be described. In this wire electric discharge machining method, FIG. 3 shows a state in which electric discharge machining is performed without oscillation in the machining progress direction. FIG. 4 shows a state in which electric discharge machining is performed that swings relative to the machining progress direction. In the oscillating machining test, “no oscillating” generally indicates the straightness accuracy of the workpiece 2 at the time of rough machining of wire electric discharge machining, that is, the first cut. The straightness accuracy in the wire electric discharge machining method varies depending on the machining conditions and the thickness of the workpiece 2.

In this wire electric discharge machining method, the workpiece 2 was rocked by moving the X-axis and the Y-axis with respect to the wire electrode 1. The rocking conditions are as follows as shown in FIG.
The swing width one-side dimension W is 0.1 mm, and the pitch P along the traveling direction is 1 μm.
In addition, the swinging movement of the oblique zigzag in the traveling direction is a swinging process by moving to the X axis and the Y axis in the order of symbols a → b → c → d → e. The results are shown in FIG. 5, FIG. 6, and FIG.

In this example, the workpiece 2 having a thickness of 50 mm, 100 mm, and 200 mm was subjected to no swing and swing processing.
FIG. 5 shows a state in which a 50 mm workpiece 2 is subjected to electric discharge machining, where (a) shows a machining locus 25A in a state where no rocking machining is performed, and (b) shows a machining in a state where rocking machining is performed. A locus 25B is shown.
FIG. 6 shows a state in which the 100 mm workpiece 2 has been subjected to electric discharge machining, where (a) shows a machining locus 26A in a state where no rocking machining is performed, and (b) shows a machining in a state where rocking machining has been performed. A locus 26B is shown.
FIG. 7 shows a state in which the 200 mm workpiece 2 has been subjected to electric discharge machining, and shows a machining locus 27A in a state in which rocking machining is not performed.

Next, regarding this wire electric discharge machining method, under the following machining conditions, (1) a plate thickness of 50 mm,
The workpiece 2 having a plate thickness of 100 mm and (3) a plate thickness of 200 mm was oscillated.
The electric discharge machining for the workpiece 2 was performed while swinging with a constant width in a direction perpendicular to the traveling direction. The wire electrode 1 is a brass material and has a diameter of 0.2 mm, and the workpiece 2 is a steel (SKD11) material.

(1) The swing width W with respect to the thickness of the workpiece 2 is 50 mm, the swing width one-side dimension is 0.07 mm,
It was performed at 0.10 mm, 0.12 mm, and 0.2 mm, and the pitch P was all performed at 1 μm. The processing conditions are as follows.
Discharge pulse (IP) -ON: 0.9 μsec
Discharge pulse (IP) -OFF: 6 μsec
Wire electrode 1 feed rate: 11 m / min
Wire electrode 1 tension: 1.1 kg
The left and right dimensions of the workpiece 2 after wire electric discharge machining of the workpiece 2 were measured at seven locations.
The results are shown in Table 1.

(2) The rocking width W is 0.07 mm, 0.10 mm, 0.12 mm, and 0.2 mm on one side of the rocking width with respect to the plate thickness 100 mm of the workpiece 2 and the pitch P is all 1 μm. went. The processing conditions are as follows.
Discharge pulse (IP) -ON: 0.8μsec
Discharge pulse (IP) -OFF: 8μsec
Wire electrode 1 feed rate: 12 m / min
Wire electrode 1 tension: 1.1 kg
The left and right dimensions of the workpiece 2 after wire electric discharge machining of the workpiece 2 were measured at nine locations.
The results are shown in Table 2.

(3) For the workpiece 2 having a thickness of 200 mm, the swinging width W was set to 0.1 mm and 0.2 mm on one side of the swinging width, and the pitch P was all set to 1 μm.
The processing conditions are as follows.
Discharge pulse (IP) -ON: 0.7 μsec
Discharge pulse (IP) -OFF: 10 μsec
Wire electrode 1 feed rate: 14 m / min
Wire electrode 1 tension: 1.1 kg
The left and right dimensions of the workpiece 2 after wire electric discharge machining of the workpiece 2 were measured at nine locations.
The results are shown in Table 3.

  In this wire electric discharge machining method, the oscillating width one-side dimension 0.1 ± 0.02 mm regardless of the plate thickness of the workpiece 2 of 50 mm, 100 mm and 200 mm from the above oscillating machining test results. It has been found that the range of the swing width increases the straightness. In addition, the fact that the machining conditions differ depending on the thickness of the workpiece 2 has confirmed that the straightness accuracy is less affected even if the machining conditions change by rocking machining. Therefore, according to the wire electric discharge machining method according to the present invention, the straightness accuracy can be improved by the swing machining of the workpiece 2, there is no need to make a second cut, and the total machining time of the workpiece 2 can be reduced. It can be shortened. Further, even if the workpiece 2 is second cut, the dimensional difference in straightness is small, so that the second cut machining time can be shortened.

  In the above-described embodiment, the wire electric discharge machining method according to the present invention was performed at a pitch P of 1 μm for the rocking progress of the workpiece 2, but in addition, a test was performed at a pitch P of 5 μm and 10 μm. As in the case of μm, it was confirmed that the straightness accuracy in the thickness direction was improved. Therefore, if the pitch P is in the range of 1 μm to 10 μm, the straightness accuracy in the thickness direction can be improved. In the above embodiment, the workpiece 2 is caused to swing obliquely with respect to the machining progress direction in the swing machining with a predetermined width in the machining progress direction. On the other hand, it was confirmed that the straightness accuracy in the thickness direction was obtained even when the workpiece 2 was swung into a circular shape or a square shape.

  This wire electric discharge machining method is used by being applied to a wire electric discharge machine that performs electric discharge machining on a workpiece with electric discharge energy generated by applying a machining voltage between a wire electrode and the workpiece.

It is a perspective view explaining the wire electric discharge machine which achieves the wire electric discharge machining method by this invention. FIG. 2 is an enlarged explanatory view showing a main part of the wire electric discharge machine of FIG. 1. It is explanatory drawing which shows the state which carries out the electrical discharge machining of the workpiece with a wire electrode with the wire electrical discharge machine of FIG. It is expansion explanatory drawing which shows the state which carries out electric discharge machining of the workpiece with this wire electric discharge machining method. It is an explanatory view showing a machining trajectory in a state in which a 50 mm workpiece is subjected to electrical discharge machining, (a) showing a machining trajectory in a state where rocking machining is not performed, and (b) showing a machining trajectory in a state where rocking machining is performed. It is an explanatory view showing a state where a 100 mm workpiece is subjected to electric discharge machining, (a) showing a machining locus in a state where rocking machining is not performed, and (b) showing a machining locus in a state where rocking machining is performed. It is explanatory drawing which shows the state which carried out the electric discharge machining of the 200 mm workpiece, and shows the machining locus in the state which does not perform rocking machining.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wire electrode 2 Work piece 3 Upper wire head 4 Lower wire head 28 Lower arm 30 Y axis slide unit 31 X axis slide unit 32 UV axis unit

Claims (8)

The wire electrode fed out from the source bobbin is opposed to the upper wire head through the supply pipe by driving the wire electrode feed roller, the workpiece installed below the upper wire head, and the workpiece below the workpiece. In a wire electric discharge machining method for supplying electric power to a lower wire head arranged in an electric field and moving the workpiece relative to the wire electrode to electric discharge machining the workpiece,
The wire electrode or the workpiece is swung in the machining progress direction with a predetermined width with respect to a machining progress direction in which the workpiece is subjected to electric discharge machining into a predetermined machining shape, and the workpiece is shaken. A wire electrical discharge machining method characterized by performing dynamic machining and increasing the straightness accuracy of the workpiece in the thickness direction. 2. The predetermined width for swinging the wire electrode or the workpiece in the machining progress direction is a swing width of 0.1 ± 0.02 mm in one-side dimension from the center in the progress direction. The wire electric discharge machining method described. 3. The wire electric discharge machining method according to claim 1, wherein a predetermined pitch for moving the wire electrode or the workpiece in a machining progress direction is in a range of 1 μm to 10 μm. 4. The rocking machining with a predetermined width in the machining progress direction causes the workpiece to rock and advance in an oblique, circular or angular shape with respect to the machining progression direction. The wire electric discharge machining method according to any one of the above. 5. The oscillating process for the workpiece is performed by applying vertical and in-phase vibrations to the workpiece in a direction perpendicular to the machining direction with respect to the wire electrode. The wire electric discharge machining method according to claim 1. 5. The oscillating process on the workpiece is performed by applying an up / down anti-phase vibration to the workpiece in a direction perpendicular to a machining progress direction with respect to the wire electrode. The wire electric discharge machining method according to claim 1. The upper phase vibration applied to the workpiece in a direction perpendicular to the machining progress direction with respect to the wire electrode in the oscillating machining for the workpiece operates the U axis and the V axis, and the lower phase vibration is applied to the X axis. The wire electric discharge machining method according to claim 5, wherein the wire electric discharge machining method is performed by operating the Y axis. The drive device for operating the X-axis slide unit, the Y-axis slide unit, and the UV-axis unit in the wire electric discharge machine that performs the rocking process on the workpiece is a linear motor to increase the vibration speed. The wire electric discharge machining method according to any one of claims 1 to 7.

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