JP2006021281A - Wire electric discharge machining method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily separate a cutoff part after machining, prevent falling of the cutoff part of a workpiece, in wire electric discharge machining. <P>SOLUTION: A machining groove 5 is formed in a workpiece 1 of a conductive material by the electric discharge machining up to a machining stopping point 4b from a machining starting point 4a, and an unmachined part 6 is left. Paraffin of a melting coagulation fixative 10a is poured into the machining groove in a state of heating the workpiece 1 to a melting point or more of the fixative by a heater 9. After applying a conductive fixative 11 to the vicinity of the machining starting point or the machining stopping point, the workpiece is cooled to a room temperature (the melting point or less) or the like, and a machined part of the workpiece is fixed and held by solidifying the melted fixative. Then, the unmachined part is cut off by the electric discharge machining, and the electric discharge machining is also repeatedly performed by securing electric conductivity by the conductive fixative, and a machining object surface superior in surface roughness can be provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a wire electric discharge machining method, and is particularly effective when machining a workpiece having a large weight or machining having a high surface roughness and little deformation.

Conventionally, when wire EDM is used for heavy workpieces, there is a risk of deformation or damage if the workpiece cut off after processing is finished, or the processing machine may be broken. Some have used a jig, or fixed a processed groove with an adhesive (for example, see Patent Document 1).
JP-A-5-4118

  However, conventionally used fall prevention jigs are cumbersome, such as requiring design according to the workpiece shape, and in order to remove the solidified adhesive from the processing groove in order to separate the cut workpiece, There is a problem that the working time becomes long because it is necessary to dissolve and remove the solidified adhesive using a solvent.

  In addition, when performing electrical discharge machining multiple times to increase the surface roughness, the last part of the machining must be cut out completely, so that the cut workpiece falls and subsequent electrical discharge machining is possible. After all, this last part has a problem that the surface roughness is low (rough).

  In view of the above points, an object of the present invention is to easily prevent a workpiece from being cut off and to separate the cut portion after processing.

  Another object of the present invention is to enable electric discharge machining a plurality of times over the entire cut surface of the workpiece.

  In order to achieve the above object, according to the first aspect of the present invention, a machining groove (5) penetrating from the upper surface (7a) to the lower surface (7b) of the workpiece is formed in the workpiece (1) made of a conductive material. In the wire electric discharge machining method that separates the workpiece into at least two parts by forming along a predetermined machining locus from 4a) to the machining end point (4a), from the machining start point of the workpiece to a point on the locus. A primary machining step in which electric discharge machining is performed up to a machining stop point (4b) that leaves an unmachined part (6), and a step in which the workpiece is heated to a temperature equal to or higher than the melting point of the melt-solidification fixing agent (10) after the primary machining step After the process of pouring the molten and solidified fixing agent (10a) in the melted state into the machining groove from the machining start point to the machining stop point of the heated workpiece, the solidification process for cooling and solidifying the molten solidification fixing agent, and the solidification process , Processing stop point A step of performing electric discharge machining to the end of machining and a step of heating the electric discharge machined workpiece to a temperature equal to or higher than the melting point temperature and discharging the molten and solidifying fixing agent poured into the machining groove from the machining groove in a molten state. It is characterized by that.

  According to the present invention, the melted and solidified fixing agent is poured into the machining groove of the wire electric discharge machined work leaving the unmachined part, and then the workpiece is cooled to solidify the molten and solidified fixing agent. The deformation of the already processed part can be prevented. In this state, even if the unprocessed part is wire-discharged and the workpiece is separated into a plurality of parts, the parts are bonded to each other by the molten and solidified fixing agent that flows into the processing groove and solidifies, so that the processed work is deformed. Or can be prevented from falling off.

  Furthermore, by heating the solidified molten and solidified fixing agent to the melting point or higher, it can be easily discharged from the machining groove, and the workpiece can be easily separated.

  Furthermore, as described in claim 2, between the step of pouring the molten and solidified fixing agent in a molten state and the solidification step, the conductive material is conductive in the vicinity of at least one of the processing stop point and the processing end point of the heated workpiece. A step of applying a soluble melting and solidifying fixative. With this conductive melt-solidifying and fixing agent, the conductivity of the workpiece can be ensured, and the unmachined portion near the machining stop point and the machining end point can be repeatedly subjected to electric discharge machining.

  In addition, as described in claim 3, after the primary processing step, the method includes a step of applying a leak-proof tape (8) so as to cover the processing locus on the lower surface of the work, and after the solidifying step, A step of removing from the workpiece can be provided. As a result, it is possible to prevent the melted and solidified fixing agent poured into the processing groove from flowing down from the lower surface of the workpiece, and after the molten and solidified fixing agent has solidified by cooling, the leakage-preventing tape is removed. Then, there will be no hindrance to the continuation of subsequent electric discharge machining.

  Furthermore, the workpiece can be heated by attaching a sheet heater (9) to the workpiece as described in claim 4.

  As described in claim 5, if the melting and solidifying fixing agent is one having a melting point between room temperature and the boiling point of water, the workpiece for melting the melting and solidifying fixing agent is used. The amount of heating heat can be reduced, thermal deformation and thermal alteration of the work can be prevented, and cooling of the work to a melting point of about room temperature can be easily performed for fixing the work.

  According to the sixth aspect of the present invention, a machining groove (5) penetrating from the upper surface (7a) to the lower surface (7b) of the workpiece is formed on the workpiece (1) of the conductive material from the machining start point (4a) to the machining end point ( In the wire electric discharge machining method in which the workpiece is separated into at least two parts by forming along a predetermined locus up to 4a), a point on the locus from the machining start point of the workpiece and an unmachined portion (6) A primary machining step in which electric discharge machining is repeated until the machining stop point (4b) is left, and after the primary machining step, the workpiece is heated to a temperature equal to or higher than the melting point of the conductive melt-solidification fixing agent (11), and heated. A step of applying a conductive melt-solidifying fixative in the vicinity of at least one of a workpiece processing stop point and a processing end point, a solidifying step of cooling and solidifying the conductive melt-solidifying fixative, a processing stop point, and processing Finish Characterized in that it comprises the the steps of repeatedly discharge machining between.

  As a result, a surface to be machined with good surface roughness can be obtained by primary electric discharge machining which is repeatedly performed while leaving an unmachined portion, and a melt-solidification fixing agent is poured into the processed groove subjected to the primary electric discharge machining to solidify the workpiece. In a state where is stably held, a conductive melting and solidifying fixing agent is applied to the unprocessed portion. As a result, since the electrical conductivity in the unmachined portion is ensured after the unmachined portion is separated into a plurality of parts by electric discharge machining, the electrical discharge machining can be repeated, and the surface roughness of the unmachined portion is also good. A surface to be processed can be formed.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 7 showing a procedure of wire electric discharge machining.

  First, as shown in FIG. 1, a workpiece 1 made of steel (S50C) having a width of 100 mm, a length of 100 mm, and a height of 100 mm is subjected to wire discharge along a predetermined processing locus from a processing start point 4a to a processing stop point 4b. Processing is performed (primary processing step). At this time, a high frequency voltage is applied to the workpiece 1 and the wire 2 by the machining power source 3 connected by the terminals 3a and 3b, and the workpiece table (not shown) on which the workpiece is placed moves along the machining locus. Advance wire electrical discharge machining. In order to cut the workpiece 1a from the workpiece 1 by this wire electric discharge machining, a machining groove 5 having a width of 0.2 mm penetrating from the upper surface 7a of the workpiece 1 to the lower surface 7b which is the bottom surface is formed.

  In the primary machining, the non-machined portion 6 is left unmachined and the electric discharge machining is temporarily stopped at the machining stop point 4b. After stopping, the machining fluid (water) around the workpiece 1 is once removed from the processing machine.

  Next, as shown in FIG. 2, the lower surface 7 b of the work 1 is sealed with a heat-resistant leak-proof tape 8 so as to close the machining groove 5. The leak-proof tape 8 can be formed into a shape along a processing locus that is grasped in advance.

  Thereafter, as shown in FIG. 3, silicon rubber heaters 9 are placed on the four side surfaces of the work 1 in a state where paraffin which is a water-insoluble melting and solidifying fixing agent 10 is placed in the vicinity of the processing groove 5 on the upper surface 7 a of the work 1. With this, the workpiece 1 is heated from room temperature to 70 ° C., which is 51 ° C. or higher, of the melting and solidifying fixing agent 10. The melt-solidifying / fixing agent 10 melts as the temperature of the workpiece 1 rises, becomes a liquid state, and flows into the processing groove 5 having a width of 0.2 mm by capillary action. In this case, the rising temperature (70 ° C.) is relatively higher than the melting point so that the melt-solidifying fixing agent 10 can surely flow into the processing groove 5 and fill it, and the heating time is shortened. Set relatively low.

  In addition, since the processing groove 5 is sealed by the leak-proof tape 8 applied to the processing groove 5 on the lower surface 7b of the work 1, the melt solidification fixing agent 10a that has flowed into the processing groove 5 is transferred from the processing groove 5 of the work 1 to the work. It will not sag outside.

  The silicon rubber heater 9 is obtained by attaching a patterned sheet heating element to a silicon rubber sheet and magnetizing one side of the heater, and can be easily attached to and detached from a metal surface.

  Next, as shown in FIG. 4, as a solidification process, the silicon rubber heater 9 is removed from the work 1, and the work 1 is cooled to a melting point of 51 ° C. or less of paraffin as the melting and solidifying fixing agent 10a to solidify the paraffin. After the melting and solidifying fixing agent 10a is solidified, the leakage prevention tape 8 is removed from the work 1. As a cooling method of the workpiece 1 at this time, natural cooling may be used, or a waste cloth soaked with water may be attached to the workpiece 1 to promote cooling.

  In addition, the melt-solidification fixing agent 10 in this embodiment uses paraffin which is a water-insoluble material. By using a water-insoluble material, it is possible to stably perform processing in a general water tank in wire electric discharge machining.

Thereafter, the workpiece 1 is cooled and held at the temperature of the machining liquid by filling the machining liquid (water) 12a maintained at room temperature (for example, 20 ° C.) from the machining liquid nozzle 12 into the machining groove 5. The adhesive strength of the paraffin as the melted and solidified fixing agent 10a poured in was guaranteed 5 kg / cm ² . This adhesive strength is large enough to hold the total weight (about 8 kg) of the cubic workpiece 1 on four sides (about 400 cm ² ).

  Therefore, the workpiece 1 and the unmachined portion 6 and the cut workpiece 1a connected to the workpiece 1 are bonded and fixed by the melt-solidification fixing agent 10a in the machining groove 5 and are held without being deformed or dropped off.

  Next, as shown in FIG. 5, the unmachined portion 6 is subjected to electric discharge machining from the machining stop point 4 b to the machining start point 4 a as the machining end point as secondary machining, and the cut workpiece 1 a is completely separated from the workpiece 1. In the first embodiment, the cut workpiece 1a is shown as an example of a shape cut out from the workpiece 1 by the machining groove 5 formed in a single stroke shape, and the machining end point coincides with the machining start point 4a. To do. However, the machining trajectory is not limited to a single stroke, and may be a machining trajectory in which the machining start point 4a and the machining end point are not matched.

  In this way, the melted and solidified fixing agent 10a is filled in the machining groove 5 from the machining start point 4a to the machining stop point 4b which is the end of the unmachined part 6, and this is solidified to form the workpiece 1 and the cut workpiece 1a. Therefore, deformation of the workpiece 1 and the cut workpiece 1a during the electric discharge machining of the unmachined portion 6 and dropping of the cut workpiece 1a can be prevented.

  Next, as shown in FIG. 6, the work 1 and the cut work 1 a that have been subjected to electric discharge machining are heated to a temperature equal to or higher than the melting point (51 ° C.) of the melt-solidifying fixative 10, for example, about 60 ° C. Is melted and discharged from the processing groove 5. In addition, the reheating of the workpieces 1 and 1a may be performed by attaching a silicon rubber heater 9 to the workpiece 1 as shown in the drawing, or it is immersed in hot water having a temperature equal to or higher than the melting point of the melting and solidifying fixing agent 10. May be.

  Thus, when the melt-solidifying / fixing agent 10a is discharged from the machining groove 5, as shown in FIG. 7, the workpiece 1 is cut out and can be easily separated from the workpiece 1a.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. In the second embodiment, the same processed part is subjected to electric discharge machining a plurality of times in order to improve the surface roughness of the work surface of the electric discharge processed workpieces 1 and 1a. In the same processing steps as those in the first embodiment, the same reference numerals are given to the respective components, and description thereof will be omitted or simplified.

  First, as shown in FIG. 8, as a primary processing step, a workpiece 1 having a width of 100 mm, a length of 200 mm, and a plate thickness of 30 mm made of stainless steel (SUS304) is deepened so that the workpiece 1 is not deformed. Wire electrical discharge machining is performed three times along a preset machining locus from 4a to the machining stop point 4b to form a machining groove 5 having a width of 0.3 mm.

  Thus, the surface roughness of the surface to be processed is improved by performing electric discharge machining a plurality of times along the same machining locus. At this time, since the unmachined portion 6 remains, the continuity between the workpiece 1 and the cut workpiece 1a is maintained by the unmachined portion 6, and electric discharge machining can be continued.

  Next, as in FIGS. 2 and 3 of the first embodiment, the lower surface 7b of the work 1 is sealed so as to close the machining groove 5 with the leak-proof tape 8 (FIG. 9), and then the upper surface 7a of the work 1 is sealed. A silicon rubber heater 9 is mounted on the upper surface 7a of the work 1 in a state where paraffin which is a water-insoluble melting and solidifying fixative 10 is placed in the vicinity of the processing groove 5, whereby the work 1 is melted and solidified fixing 10 from room temperature. Is heated to 90 ° C., which is 75 ° C. or higher (FIG. 10). That is, in the second embodiment, the melting and solidifying fixing agent 10 having a paraffin melting point of 75 ° C. is used. As described above, paraffin has a fine melting point range, and it is possible to select a paraffin having a melting point according to the purpose in electric discharge machining.

  Next, in the second embodiment, steps not performed in the first embodiment are performed. That is, as shown in FIG. 11, the conductive melting and solidifying fixing agent 11 is placed near the processing start point 4 a on the upper surface 7 a of the workpiece 1. The conductive melt-solidifying fixative 11 is composed of 50% by weight of paraffin having a melting point of 75 ° C. and 50% by weight of carbon particles having an average particle diameter of 5 μm. Unlike the melt-solidifying fixative 10 which is an insulator, Conductivity is provided by carbon particles mixed in paraffin.

  The conductive melt-solidifying / fixing agent 11 placed in the vicinity of the processing start point 4a is melted on the workpiece 1 that has already been heated, and part of it remains in the vicinity of the unprocessed portion 6, and part of the processing start point 4a and processing. It flows into the processing groove 5 from the stop point 4b and is mixed with the melt-solidification fixing agent 10a. At this time, due to the leak-proof tape 8 applied to the lower surface 7b of the work 1, the molten and solidified fixing agent 10a and the conductive molten and solidified fixing agent 11 that have flowed into the processed groove 5 hang down from the processed groove 5 of the work 1 to the outside of the work. There is no.

Next, as in FIG. 4 of the first embodiment, as the solidification process, the work 1 is cooled to a melting point of 75 ° C. or less of the fixing agent 10a, and the molten and solidified fixing agent 10a poured into the machining groove 5 and the conductive melting and solidification. After the fixing agent 11 is solidified, the leakage prevention tape 8 on the lower surface 7b of the workpiece 1 is removed, and the machining fluid (water) 12a maintained at room temperature (for example, 20 ° C.) is filled inside the machining machine, whereby the workpiece 1 is also removed. It is cooled and held at the temperature of the working fluid (FIG. 12). As a result, the adhesive strength of paraffin as the melt-solidification fixing agent 10a solidified in the processing groove 5 was guaranteed to be 15 kg / cm ² .

  Next, as shown in FIG. 13, electric discharge machining is performed a plurality of times (for example, three times) on the same machining locus from the machining stop point 4b to the machining start point 4a as the machining end point for the unmachined portion 6 as secondary machining. To improve the surface roughness of the surface to be processed.

  At this time, even if the workpiece 1 and the cut workpiece 1a are completely separated during the first electric discharge machining from the machining stop point 4b to the machining start point 4a, both the machining stop point 4b and the machining start point 4a are provided. The electrical conductivity between the cut workpiece 1 and the cut workpiece 1a is ensured by the action of the conductive melting and solidifying fixing agent 11 existing on the surface of the unprocessed portion 6 between the two, so that repeated electric discharge machining is possible. Thus, this unprocessed portion 6 can also improve the surface roughness.

  After the electric discharge machining is completed, the upper surface 7a of the workpiece 1, that is, the upper surface of the cut workpiece 1a, is formed on the molten and solidified fixing agent 10 and the conductive molten and solidified fixing agent 11 in the same manner as in FIGS. The molten solidification fixing agent 10a is melted by being immersed in a silicon rubber heater 9 or hot water up to a temperature equal to or higher than the melting point (75 ° C.), for example, about 90 ° C., and discharged from the processing groove 5 (FIG. 14).

  When the molten and solidified fixing agent 10a and the conductive molten and solidified fixing agent 11 are discharged from the processing groove 5, as shown in FIG. 15, the workpiece 1 is cut out and can be easily separated from the workpiece 1a.

  As described above, in the second embodiment, after the electric discharge machining is performed a plurality of times while leaving the unmachined portion 6 in the primary machining, the molten and solidified fixing agent 10a is poured into the primary machining groove 5 to be solidified. 1 is bonded to the processed cut workpiece 1a, so that when the unmachined portion 6 is subjected to secondary machining by electric discharge machining, the workpieces 1 and 1a are not deformed or dropped, and the secondary machining can be performed stably. It can be performed.

  Furthermore, in this 2nd Embodiment, since the electroconductive melt-solidification fixing agent 11 is apply | coated to the unprocessed part 6 vicinity, with this electroconductive melt-solidification fixing agent 11, the workpiece | work 1 in the unprocessed part 6 and the cut workpiece 1a are carried out. Conductivity can be ensured. Therefore, in this electroconductive melt-solidifying / fixing agent 11, the unmachined portion 6 can be repeatedly subjected to electric discharge machining, and a machined surface with good surface roughness can be obtained.

  And, since paraffin is used as these melting and solidifying fixing agent, it can be solidified at room temperature to easily bond the workpiece and the cut workpiece, and has a relatively low melting point (100 ° C. or lower), The easily solidified molten and solidified fixing agent can be melted and removed.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG. The third embodiment uses a workpiece 1 made of the same steel material (S50C, size 100 × 100 × 100 (mm)) as in the first embodiment, and performs electric discharge machining a plurality of times as in the second embodiment. The same steps as those of the first and second embodiments are performed in that a processed surface with good surface roughness is obtained. In the third embodiment, when the water-insoluble melting and solidifying fixing agent 10 and the conductive melting and solidifying fixing agent 11 are further applied to the workpiece 1 and poured into the machining groove 5, the falling prevention plate is applied to the workpiece 1. 13 is also used.

  In the following description of the third embodiment, description of the same steps as those in the first and second embodiments will be omitted or simplified, and differences will be mainly described.

  First, as a primary machining step, in FIG. 1, the machining groove 5 is formed by performing electric discharge machining a plurality of times between the machining start point 4 a and the machining stop point 4 b of the workpiece 1, and the machining groove 5 with good surface roughness is formed. Get a non-machined surface. Next, a leak-proof tape 8 having a shape corresponding to the machining locus is applied to the lower surface 7b of the work 1 to seal the machining groove 5 (FIG. 2). Next, as shown in FIG. 3, a silicon rubber heater 9 is attached to the side surface of the work 1 and the work 1 is heated to about 90 °, so that the water-insoluble melt-solidification fixing agent (melting point) used in the second embodiment is used. (75 ° paraffin) 10 is placed near the machining groove 5, melted by the heat of the work 1, and poured into the machining groove 5.

  At the same time, as shown in FIG. 16, a drop prevention plate 13 is placed on the upper surface 7a of the workpiece 1 so as to cover the workpiece 1 and the cut workpiece 1a simultaneously. At this time, the molten and solidified fixing agent 10a in the molten state in the vicinity of the machining groove 5 flows between the lower surface of the drop-off prevention plate 13 and the upper surface of the workpiece 1 and the cut workpiece 1a by capillary action, and the gap between the two melts and solidifies. Filled with fixative 10b.

  Further, in FIG. 16, as in the second embodiment (FIG. 11), conductive melt solidification comprising 50% by weight of paraffin having a melting point of 75 ° C. and 50% by weight of carbon particles having an average particle diameter of 5 μm is formed in the vicinity of the processing start point 4a. The fixing agent 11 is applied to ensure the conductivity of the unprocessed portion 6.

  After that, the workpiece 1 is cooled to a melting point of 75 ° C. or lower by fixing the workpiece 1 with natural cooling or water-soaked waste by the solidification step shown in FIG. 11 is solidified, and after the solidification, the leak-proof tape 8 on the lower surface 7b of the work 1 is removed.

  After the melting and solidifying fixing agents 10a, 10b, and 11 are solidified, the workpiece 1 and the drop-off prevention plate 13 are also cooled to 20 ° C. by the processing liquid 12a that is maintained at about room temperature (20 ° C.) filled in the processing machine. Thus, the adhesive strength of the melting and solidifying fixing agents 10a and 10b is guaranteed to be 15 kg / cm 2. The cut workpiece 1a is held without dropping from the workpiece 1 due to the adhesive strength between the melt-solidification fixing agent 10a in the machining groove 5 and the fusion-solidification fixing agent 10b on the lower surface of the drop-off preventing plate 13.

  Thereafter, in FIG. 5, as in the second embodiment, the conductive action of the conductive melting and solidifying fixing agent 11 applied in the vicinity of the processing start point 4a is caused between the processing stop point 4b and the processing start point 4a. The unprocessed portion 6 can be subjected to electric discharge machining a plurality of times, and a processed surface with good surface roughness can be obtained also in this portion. In the electric discharge machining of the unmachined portion 6, even if the workpiece 1 a is completely cut out by the melted and solidified fixing agent 10 a that has flowed into the machining groove 5 and solidified, the drop prevention plate 13, and the solidified melted and solidified fixing agent 10 b. This prevents the workpiece 1 from falling off or deforming.

  After the electric discharge machining is completed, in FIG. 6, the workpiece 1 is reheated to a melting point of 75 ° C. or higher by melting the solidification fixing agent 10 by immersing the workpiece 1 in hot water of 90 ° C. or higher by the silicon rubber heater 9, The melted and solidified fixing agents 10a and 10b are removed from the processing groove 5 and the lower surface of the drop-off preventing plate 13. Thereby, as shown in FIG. 7, the cut workpiece 1 a and the drop-off preventing plate 13 can be easily separated from the workpiece 1.

It is a figure which shows the first process of the wire electric discharge machining of 1st Embodiment of this invention. It is a figure which shows the 2nd process of the wire electric discharge machining of 1st Embodiment. It is a figure which shows the 3rd process of the wire electric discharge machining of 1st Embodiment. It is a figure which shows the 4th process of the wire electric discharge machining of 1st Embodiment. It is a figure which shows the 5th process of the wire electric discharge machining of 1st Embodiment. It is a figure which shows the 6th process of the wire electric discharge machining of 1st Embodiment. It is a figure which shows the 7th process of the wire electric discharge machining of 1st Embodiment. It is a figure which shows the first process of the wire electric discharge machining of 2nd Embodiment of this invention. It is a figure which shows the 2nd process of the wire electric discharge machining of 2nd Embodiment. It is a figure which shows the 3rd process of the wire electric discharge machining of 2nd Embodiment. It is a figure which shows the 4th process of the wire electric discharge machining of 2nd Embodiment. It is a figure which shows the 5th process of the wire electric discharge machining of 2nd Embodiment. It is a figure which shows the 6th process of the wire electric discharge machining of 2nd Embodiment. It is a figure which shows the 7th process of the wire electric discharge machining of 2nd Embodiment. It is a figure which shows the 8th process of the wire electric discharge machining of 2nd Embodiment. It is a figure which shows 1 process of the wire electric discharge machining of 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Work, 1a ... Cutting work, 3 ... Processing power supply, 4a ... Processing start point,
4b ... processing stop point, 5 ... machined groove, 6 ... unprocessed part, 8 ... heat-resistant leak-proof tape,
9 ... Silicon rubber heater, 10, 10a, 10b ... Non-water-soluble melting and solidifying fixative,
11: Conductive melting and solidifying fixing agent, 13: Drop-off prevention plate.

Claims (6)

A predetermined machining locus from the machining start point (4a) to the machining end point (4a) through the machining groove (5) penetrating the workpiece (1) from the upper surface (7a) to the lower surface (7b) of the workpiece. In the wire electric discharge machining method for separating the workpiece into at least two parts by forming along
A primary machining step of performing electrical discharge machining from a machining start point of the workpiece to a machining stop point (4b) that is a point on the trajectory and leaves an unmachined portion (6);
After the primary processing step, the step of heating the workpiece to a temperature equal to or higher than the melting point temperature of the melting and solidifying fixing agent (10);
Pouring the molten and solidifying fixing agent (10a) in a molten state into the processing groove from the processing start point to the processing stop point of the heated workpiece;
A solidification step of cooling and solidifying the melt-solidifying fixative;
After the solidification step, electric discharge machining from the machining stop point to the machining end point;
Heating the electric discharge machined work above the melting point temperature, and discharging the molten and solidified fixing agent poured into the machining groove from the machining groove in a molten state;
A wire electric discharge machining method comprising: Between the step of pouring the molten and solidified fixing agent in a molten state and the solidifying step, a conductive molten and solidified fixing agent is provided in the vicinity of at least one of the processing stop point and the processing end point of the heated workpiece. The wire electric discharge machining method according to claim 1, further comprising a coating step. After the primary processing step, including a step of applying a leak-proof tape (8) so as to cover the processing locus on the lower surface of the workpiece,
The wire electric discharge machining method according to claim 1, further comprising a step of removing the leak-proof tape from the workpiece after the solidifying step. The wire electric discharge machining method according to any one of claims 1 to 3, wherein the step of heating the workpiece is performed by attaching a sheet heater (9) to the workpiece. The wire electric discharge machining method according to any one of claims 1 to 4, wherein the melting and solidifying fixing agent has a melting point between room temperature and a boiling point of water. A machining groove (5) penetrating from the upper surface (7a) to the lower surface (7b) of the workpiece on the workpiece (1) made of a conductive material has a predetermined locus from the machining start point (4a) to the machining end point (4a). In the wire electric discharge machining method for separating the workpiece into at least two parts by forming along
A primary machining step in which electric discharge machining is repeatedly performed from a machining start point of the workpiece to a machining stop point (4b) that is a point on the locus and leaves an unmachined portion (6);
After the primary processing step, heating the workpiece to a temperature equal to or higher than the melting temperature of the conductive melting and solidifying fixative (11);
Applying the conductive melting and solidifying fixative in the vicinity of at least one of the processing stop point and processing end point of the heated workpiece;
A solidification step of cooling and solidifying the conductive melting and solidifying fixative;
A step of repeatedly electric discharge machining between the machining stop point and the machining end point;
A wire electric discharge machining method comprising:

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