JP5785410B2 - Multi-wire electric discharge machining apparatus and method for producing silicon carbide plate using the same - Google Patents

Description

  The present invention relates to a structure of a multi-wire electric discharge machining apparatus and a method for manufacturing a silicon carbide plate using the multi-wire electric discharge machining apparatus.

  Conventionally, a wire saw using abrasive grains is known as a cutting means in the case of cutting a wafer from a cylindrical ingot such as silicon. In this wire saw, a cutting wire wound between a plurality of guide rollers is driven at a high speed in the longitudinal direction, and the workpiece is cut and fed to the wire, thereby simultaneously cutting a large number of thin pieces from the workpiece. is there.

  However, in such a wire saw, it is necessary to simultaneously supply a processing liquid (slurry) mixed with processing abrasive grains to a plurality of cutting wire portions formed between guide rollers, and handling thereof is not easy. . Moreover, in order to suppress the disconnection due to the direct contact of the wire with the workpiece, it is necessary to use a relatively thick wire, and there is a problem that a cutting work cost increases. Furthermore, the conventional wire saw sometimes takes a long time to cut out a wafer from an ingot, and the need for shortening the processing time is increasing.

  On the other hand, in recent years, silicon carbide has attracted attention as a semiconductor material. However, since this silicon carbide is a hard material, the conventional wire saw has a problem that it takes more time than cutting a silicon ingot.

  Therefore, development of an electric discharge type wire saw in which a voltage is intermittently applied between a silicon carbide ingot and a cutting wire, and the ingot is cut by the principle of electric discharge machining by each cutting wire portion (for example, a patent) Reference 1). In Patent Document 1, a plurality of cutting wire portions are formed by winding a single cutting wire around a plurality of guide rollers, and an energizing member is provided in contact with each strip, and each strip, a semiconductor ingot, A method has been proposed in which a voltage is applied between the two to generate a discharge and simultaneously cut three or more semiconductor ingots.

  On the other hand, it is required to cut a wafer from an ingot at high speed. In response to this request, the number of times the wire is wound around the guide roller is increased to increase the number of sections of the cutting wire portion, and an electric discharge machining power is applied to each of the cutting wire portions, and between each cutting wire portion and the workpiece. It is conceivable to increase the cutting speed by generating a plurality of discharges at the same time. In this case, since one wire is wound around the guide roller to form a plurality of wire cutting portions, each cutting wire portion is in an electrically connected state. For this reason, in order to apply electric discharge machining power to each cutting wire part, it is necessary to insulate each cutting wire part by some method. Thus, it has been proposed to increase the impedance between the cutting wire portions by making the wires coiled between the cutting wire portions so as to be in an electrically insulated state (see, for example, Patent Document 2). . Further, it has been proposed to arrange a coiled wire around the cores that are magnetically insulated from each other to further increase the electrical insulation between the cutting wire portions (for example, Patent Documents). 3)

  In the prior art described in Patent Documents 2 and 3, since it is necessary to apply electric discharge machining power to each cutting wire portion, the same number of conductor blocks and insulating blocks as the cutting wire portions contacting each wire of the strip Are arranged in an alternating manner, and an electrode unit is proposed in which each block is tightened and integrated with a bolt (see, for example, Patent Document 4). However, since the conductive block is worn by rubbing the wire with the conductive block, it is necessary to frequently replace the conductive block. For this reason, in the multi-wire electric discharge machining apparatus, a method has been proposed in which the conductor is made of a hard cemented carbide (see, for example, Patent Document 5).

  Further, a method has been proposed in which a slip ring that contacts a roller that defines a plurality of cutting wire portions is provided, and current is supplied to each cutting wire portion in parallel via the slip ring and the rollers (see, for example, Patent Document 6).

Japanese Patent Laid-Open No. 9-248719 JP 2000-94221 A JP 2006-75952 A JP 2000-107941 A JP 2009-166211 A Japanese Patent Laid-Open No. 10-55508

  By the way, in the multi-wire electric discharge machining apparatus having a plurality of cutting wire portions as described in Patent Documents 1 to 6, the plurality of cutting wire portions are formed by winding one wire around a roller or the like a plurality of times. Therefore, one wire discharges between the workpiece several times. Since the workpiece component adheres to the surface of the wire each time it is discharged, when a hard material such as silicon carbide is sliced by electric discharge machining, the cutting wire portion to which silicon carbide powder is attached is sent to the next wire cutting portion. When contacting the conductive block for power feeding, there is a problem that the silicon carbide powder adhering to the surface of the wire acts like a grindstone and wears the surface of the conductive block. Since silicon carbide is very hard, even the cemented carbide like the prior art described in Patent Document 5 is easily worn on the surface, and it is necessary to frequently replace the conductive block. It becomes. Moreover, in the prior art described in Patent Documents 1 to 5, since there is a slip between the wire and the surface of the conductive block, there is an instantaneous gap between the wire and the conductive block, There is a case where a discharge occurs between the two and the conductive block is scraped off by this discharge. For this reason, the conventional techniques described in Patent Documents 1 to 5 have a problem that it is difficult to stably perform long-time processing as in the case of slicing a hard material such as silicon carbide having a large diameter.

  Moreover, since the cemented carbide like the prior art described in patent document 5 has low electrical conductivity, the voltage which supplies electric power to each strip | wire of a wire falls, and the case where a material with high electrical conductivity is used for an electrode There is a problem that the cutting speed of the ingot is reduced as compared with the above. In addition, when slicing a hard material such as silicon carbide having a large diameter, the processing time becomes long. Therefore, a material that has high electrical conductivity but is easily worn is used for the roller that defines the cutting wire portion. In some cases, the roller wears during processing, the distance between the cutting wire portion and the ingot changes, and the discharge becomes unstable. For this reason, the roller that defines the cutting wire portion is made of a material having a low hardness and low hardness even when the wire is wound, so that the roller has a slip ring as described in Patent Document 6. Even when electric discharge machining power is applied via the wire, the voltage to be fed to each strip of the wire is reduced, and the cutting speed of the ingot is reduced as compared with the case of directly feeding the wire with the electrode having high electrical conductivity. There was a problem. Furthermore, in the prior art described in Patent Document 6, the voltage supplied to each strip of the wire is further reduced due to the electrical resistance caused by the contact between the slip ring and the roller, and the wire is directly fed by the electrode having high electrical conductivity. There is a problem that the cutting speed of the ingot is reduced as compared with the above.

  In the prior art described in Patent Documents 1 to 5, the pulse power for performing electric discharge machining is such that the work is connected to the positive side of the power source, and the wire is connected to the negative side of the power source via the switching transistor. Is turned on and off to apply an electric discharge machining pulse between the workpiece and the wire. However, if there is a case where no electric discharge occurs even when an electric discharge machining pulse is applied, the electric charge due to the previous electric discharge machining pulse application remains in a capacitor or the like provided in the power supply system, and subsequent electric discharge is not effective. It may become stable. In this case, it is conceivable to extend the period of applying the discharge pulse so that the next electric discharge machining pulse is applied after the remaining charge is discharged to some extent. However, since the speed of electric discharge machining depends on the number of discharges in a predetermined time, that is, the number of electric discharge machining pulses applied in a predetermined time, if the next electric discharge machining pulse is applied after waiting for the discharge of the remaining charge, the machining time is reduced. There was a problem that it could not be shortened.

  Therefore, an object of the present invention is to improve the machining speed and stably perform long-time machining in a wire electric discharge machining apparatus.

The multi-wire electric discharge machining apparatus according to the present invention includes a guide roller set including a plurality of guide rollers arranged at intervals, and is wound around the guide roller set a plurality of times at intervals in the longitudinal direction of each guide roller. A plurality of cutting wire portions separated from each other between a pair of adjacent guide rollers of the guide roller set, and arranged on both sides in the wire longitudinal direction of each set of cutting wire portions. A plurality of machining units including a plurality of rotating electrodes that are in contact with the respective strips of the wire and rotate in the same direction as the wire feed direction to supply a common electric discharge machining power to the respective strips of the wire; A machining power source for supplying electric discharge machining power to the electrodes, and each guide roller of each machining unit is coaxially disposed adjacent to each other in the direction of each rotation axis, and each adjacent machining unit The guide rollers of each machining unit are electrically insulated from each other, the rotating electrodes of the machining units are arranged coaxially adjacent to each other in the direction of the rotation axis, and the rotating electrodes of the neighboring machining units are electrically insulated from each other. Each set of cutting wire portions of each processing unit is arranged side by side in the longitudinal direction of the wire, and each rotating electrode is arranged in the wire feeding direction of the first cutting wire portion set on the most upstream side along the wire feeding direction. A first rotating electrode disposed on the upstream side, a second rotating electrode disposed on the downstream side in the wire feeding direction of the second cutting wire subset located on the most downstream side along the wire feeding direction, and wire feeding A third rotating electrode provided in the middle of each set of cutting wire portions along the direction, and each set of cutting wire portions of each processing unit while feeding each wire of each processing unit in the winding direction; each Characterized by processing each workpiece performing discharge between the over click.

In the multi-wire electric discharge machining apparatus of the present invention, each rotating electrode is preferably a cylindrical conductor .

  In the multi-wire electric discharge machining apparatus of the present invention, each rotary electrode is arranged one by one at an equidistant position in the opposite direction along the wire winding direction from the center of each set of cutting wire portions. Each processing unit is arranged upstream or downstream or both sides in the wire feeding direction of each rotating electrode or opposed to each rotating electrode, and rotates each wire of each processing unit. It is also preferable to provide a plurality of idle rollers pressed against the electrodes, and it is also preferable that each idle roller sandwiches each strip of the wire of each processing unit between each rotary electrode.

  In the multi-wire electric discharge machining apparatus of the present invention, each conductive bearing in which each rotating electrode is attached to the outside of the outer ring, a shaft in which the inner ring of each conductive bearing is electrically insulated and mounted coaxially, and each conductive Including a power supply member electrically connected to each inner ring of the bearing, and a rotation shaft on which each rotary electrode is insulated and attached to the outer surface of each rotary electrode. Each connecting electrode for supplying electric discharge machining power to each rotating electrode.

  In the multi-wire electric discharge machining apparatus according to the present invention, the electric discharge machining power is preferably a high-frequency pulse including an electric discharge machining pulse and a residual charge discharging pulse following the electric discharge machining pulse with a voltage opposite to the electric discharge machining pulse. In addition, the machining power source includes at least one main switching transistor for generating an electric discharge machining pulse, at least one main DC power supply, and a residual charge neutralizing pulse having a voltage opposite to that of the electric discharge machining pulse in order to remove the residual charge after the electric discharge machining. It is also preferable to include a plurality of machining power supply units that include at least one sub-switching transistor and at least one sub-direct current power source that generate electrical discharge and supply electric discharge machining power to each machining unit.

The silicon carbide plate manufacturing method of the present invention includes a guide roller set including a plurality of guide rollers arranged at intervals, and is wound around the guide roller set a plurality of times at intervals in the longitudinal direction of each guide roller. A plurality of cutting wire portions separated from each other between a pair of adjacent guide rollers in the guide roller set, and arranged on both sides in the wire longitudinal direction of each set of cutting wire portions. A plurality of rotating units that contact each strip of the wire and rotate in the same direction as the wire feed direction to feed a common electric discharge machining power to each strip of the wire, and a plurality of machining units, A machining power supply for supplying electric discharge machining power to the rotating electrodes, and each guide roller of each machining unit is coaxially arranged adjacent to each other in the direction of each rotation axis. The guide rollers are electrically insulated from each other, the rotary electrodes of the machining units are coaxially arranged adjacent to each other in the direction of the rotary shaft, and the rotary electrodes of the neighboring machining units are electrically insulated from each other. Each set of cutting wire portions of each processing unit is arranged side by side in the longitudinal direction of the wire, and each rotary electrode is a first cutting on the most upstream side along the wire feed direction. A first rotating electrode disposed on the upstream side of the wire portion in the wire feeding direction; and a second rotating electrode disposed on the downstream side in the wire feeding direction of the second cutting wire portion located on the most downstream side in the wire feeding direction. a rotary electrode, along the wire feed direction and a third rotating electrodes respectively provided on each set of intermediate cutting wire portion, each machining unit while feeding each wire of each machining unit winding direction A method of manufacturing a silicon carbide plate by cutting a plurality of silicon carbide plates from each silicon carbide ingot by discharging between each set of cutting wire portions and each silicon carbide ingot, comprising: The high frequency pulse is generated by turning it on and off, and this high frequency pulse is supplied as electric power for electric discharge machining.

  In the method for producing a silicon carbide plate of the present invention, it is also preferable that the positions in the direction intersecting with each set of cutting wire portions of each silicon carbide ingot are made different.

  The present invention has the effect of improving the machining speed and stably performing long-time machining in a wire electric discharge machining apparatus.

It is a systematic diagram which shows the structure of the multi-wire electric discharge machining apparatus in embodiment of this invention. It is explanatory drawing which shows the rotating electrode and cutting wire part of the multi-wire electric discharge machining apparatus in embodiment of this invention. It is explanatory drawing which shows the rotating electrode and the deposit | attachment of a wire of the multi-wire electric discharge machining apparatus in embodiment of this invention. It is explanatory drawing which shows the support structure of the rotating electrode of the multi-wire electric discharge machining apparatus in embodiment of this invention. It is explanatory drawing which shows the structure of the process power supply of the multi-wire electric discharge machining apparatus in embodiment of this invention. It is explanatory drawing which shows the waveform of the high frequency pulse for electric discharge machining of the multi-wire electric discharge machining apparatus in the embodiment of the present invention. It is explanatory drawing which shows the state of the electric discharge machining of the multi-wire electric discharge machining apparatus in embodiment of this invention. It is a perspective view which shows the support structure of the rotating electrode of the multi-wire electric discharge machining apparatus in other embodiment of this invention. It is explanatory drawing which shows the support structure of the rotating electrode of the multi-wire electric discharge machining apparatus in other embodiment of this invention. It is explanatory drawing which shows the rotating electrode and cutting wire part of the multi-wire electric discharge machining apparatus in other embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the multi-wire electric discharge machining apparatus 100 of the present embodiment includes a first upper cutting wire portion 261A and a first lower cutting wire portion 261B around which a first wire 151 is wound. The first processing unit 101 and the second processing unit 102 including the second upper cutting wire portion 262A and the second lower cutting wire portion 262B around which the second wire 152 is wound are arranged side by side in parallel. It is the composition arranged in. The first machining unit 101 includes a delivery bobbin 10A that sends out a first wire 151 that is a metal wire such as brass, iron wire, tungsten wire, and molybdenum wire that is rotationally driven by a delivery motor 25A and used for electric discharge machining, and a slip clutch. 22, a take-up bobbin 10 </ b> B that is driven by a take-up motor 25 </ b> H attached via 22 to take up the first wire 151, pulleys 11 </ b> A to 11 </ b> I that define a feed path of the first wire 151, and the first wire A dancer roll 12 that adjusts the travel length of 151 to stabilize the travel of the first wire 151, and a non-slip member made of rubber is provided on the surface around which the first wire 151 is wound, and is driven by a speed motor 25B. A speed pulley 16 that defines the feed speed of the first wire 151, and a first wire tension sensor 3A, a second wire tension sensor 13B and a torque motor 25D capable of adjusting the output torque, and a rubber non-slip member is attached to the surface around which the first wire 151 is wound. The tension wire 18 that sandwiches the first wire 151 between the clamp unit 19 and the clamp roller 19a provided opposite to each other and pulls in the feeding direction to apply tension to the first wire 151, and the positioning motor 25G A plurality of guides constituting a wire alignment unit 21 that moves in the axial direction, and a plurality of first upper cutting wire portions 261A and a first lower cutting wire portion 261B by winding the first wire 151 a plurality of times. A set of guide rollers including rollers 24A to 24H and three rotating electrodes 2 around which the first wire 151 is wound and rotated 0A _1, and 200B _1, 200C _1, includes a respective rotating electrode 200A _1, 200B _1, first on the surface of the 200C ₁ 1 of each idle roller 300A is pressed against the wire _{151 1, 300B 1, 300C 1} , a. Each rotary electrode 200A ₁ , 200B ₁ , 200C ₁ is configured to rotate around each shaft fixed so as not to rotate. As shown in FIG. 1, the rotary electrode 200A ₁ is disposed on the upstream side in the feed direction of the first wire 151 of the first upper cutting wire portion 261A on the upstream side in the feed direction of the first wire 151. The rotary electrode 200B ₁ is disposed on the downstream side in the feed direction of the first wire 151 of the first lower cutting wire portion 261B on the downstream side in the feed direction of the first wire 151, and the rotary electrode 200C ₁ Are arranged in the middle of the first upper cutting wire portion 261A and the first lower cutting wire portion 261B along the feeding direction of the first wire 151.

The first wire 151 fed from the delivery bobbin 10A in the direction of the arrow R shown in FIG. 1 includes a pulley 11A, a dancer roll 12, pulleys 11B and 11C, a speed pulley 16, a pulley 11D, a first wire tension sensor 13A, The first wires 151 wound around the pulleys 11E and 11F and exiting the pulley 11F are guide rollers 24A to 24H having a number of guide grooves, rotating electrodes 200A ₁ and 200B ₁ , idle rollers 300A ₁ and 300B ₁ , the outer surface of the 300C _1, guide rollers 24A, idle rollers 300A _1, rotating electrode 200A _1, guide rollers 24B, 24G, idle rollers 300C _1, guide rollers 24H, 24C, rotating electrode 200B _1, the idle roller 300B _1, the guide roller 24D , 24E, 24F. The _first electrode 151 is sandwiched between the rotating electrode 200C _{1 and} the idle roller 300C ₁ . Each of the guide rollers 24A to 24H is common between the first processing unit 101 and the second processing unit 102. The first wire 151 that has exited the guide roller 24F is separated from the guide roller 24A again from a position that is separated from the portion of the first wire 151 that is initially wound around the guide roller 24A by a pitch P in the axial direction of the guide roller 24A. It is wound around 24H. The axial distance between each of the guide rollers 24A to 24H between the portion of the first wire 151 wound first and the portion of the first wire 151 wound next is the pitch P at any location. It has become. Thus, the first wire 151 is wound around the guide rollers 24A to 24H, the rotating electrodes 200A ₁ and 200B ₁ , and the idle rollers 300A ₁ , 300B ₁ , and 300C _{1 a} plurality of times, and is in contact with the rotating electrode 200C ₁ a plurality of times. The first wire 151 is wound around the guide rollers 24A to 24H, the rotating electrodes 200A ₁ and 200B ₁ , the idle rollers 300A ₁ , 300B ₁ , and 300C ₁ a plurality of times, and after contacting the rotating electrode 200C ₁ a plurality of times, It passes through the pulley 11G, the second wire tension sensor 13B, the pulley 11H, the tension pulley 18, the pulley 11I, and the wire alignment unit 21, and is wound around the winding bobbin 10B.

  As shown in FIG. 1, in the present embodiment, the first wire 151 is wound around the guide rollers 24A to 24H five times, and the first wire 151 has five strips. Here, the number of windings is the number of times the guide rollers 24B and 24G defining the first upper cutting wire portion 261A and the guide rollers 24H and 24C defining the first lower cutting wire portion 261B are wound. is there. Therefore, even if the first wire 151 extends toward the pulley 11G without returning from the guide roller 24F to the guide roller 24A as in the last winding of the first wire 151, the first wire 151 is wound around the guide rollers 24B to 24C. Therefore, the winding number is counted as one time. That is, the number of windings is the number of the first upper cutting wire portion 261A stretched between the guide roller 24B and the guide roller 24G and the first stretched between the guide roller 24H and the guide roller 24C. The number of lower cutting wire portions 261B is five, and in this embodiment, the number of first upper and lower cutting wire portions 261A and 261B is five. In the present embodiment, for the sake of explanation, the number of windings of the first wire 151 is five, the number of strips is five, and the first upper and lower cutting wire portions 261A and 261B are each described as five. However, the number of windings and the number of strips may be more than this, or the number of windings and the number of strips less than this may be used.

  The second machining unit 102 has the same configuration as that of the first machining unit 101 described above, and is used for feeding the second wire 152. The delivery bobbin 10A, the take-up bobbin 10B, and the pulleys 11A to 11A. 11I, dancer roll 12, speed pulley 16, first wire tension sensor 13A, second wire tension sensor 13B, torque motor 25D, clamp unit 19, clamp roller 19a, tension pulley 18, and positioning The motor 25G and the wire alignment unit 21 are installed in parallel in the vertical direction, for example, independently of each device for feeding the first wire 151. However, in FIG. 1, illustration of each device used for feeding these second wires 152 is omitted.

The second processing unit 102 includes a guide roller set including common guide rollers 24A to 24H in which the second wire 152 is wound a plurality of times to form a plurality of second upper and lower cutting wire portions 262A and 262B. A plurality of rotating electrodes 200A ₂ , 200B ₂ , and 200C ₂ around which the second wire 152 is wound, and an idle roller that presses the second wire 152 against the surfaces of the rotating electrodes 200A ₂ , 200B ₂ , and 200C ₂ 300A ₂ , 300B ₂ , 300C ₂ . As shown in FIG. 1, each rotary electrode 200A ₂ , 200B ₂ , 200C ₂ , idle roller 300A ₂ , 300B ₂ , 300C _{2 of} the second machining unit 102 is also associated with each rotary electrode 200A _{1 of} the first machining unit 101. , 200B ₁ , 200C ₁ , the corresponding idle rollers 300A ₁ , 300B ₁ , 300C _1, and the respective rotating electrodes 200A ₁ , 200B ₁ , 200C ₁ , 200A ₂ , 200B ₂ , 200C ₂ , each idle roller 300A ₁ , 300B ₁ , 300C ₁ , 300A ₂ , 300B ₂ , 300C ₂ are arranged adjacent to each other in the direction of the rotation axis, and each rotary electrode 200A ₂ , 200B ₂ , 200C ₂ , each idle roller 300A _{2 of} the second processing unit 102 is arranged. , 300B _2, each corresponding rotating electrode 200 of the first processing unit 101 and an adjacent 300C _{2 1,} 200B _1, 200C _1, and is electrically insulated from the respective idle rollers _{300A 1, 300B 1, 300C 1} .

  In FIG. 1, in order to distinguish and describe the first processing unit 101 and the second processing unit 102, the leftmost strip of the first wire 151 of the first processing unit 101 shown in FIG. The spacing in the rotation axis direction of each guide roller 24A to 24H between the rightmost strip of the two processing units 102 is drawn wider than the pitch P. In this embodiment, FIG. 1, the guide rollers 24 </ b> A to 24 </ b> H between the leftmost end of the first wire 151 shown in FIG. 1 of the first processing unit 101 and the rightmost end of the second processing unit 102. The interval in the rotation axis direction is a pitch P. However, this interval is not limited to the pitch P, and may be wider or narrower than this.

  The multi-wire electric discharge machining apparatus 100 according to this embodiment includes two silicon carbide ingots 28 </ b> A and 28 </ b> B that are workpieces to be machined by a first machining unit 101 and a second machining unit 102. The upper cutting wire portions 261A and 262A and the lower cutting wire units 261B and 262B, feed units 27A and 27B for sending to the machining units 101 and 102, and the power supply 29 and the machining units. 101, a workpiece feeding unit 27 </ b> A, 27 </ b> B, a power source 29, and a control unit 80 that controls each device for feeding each wire 151, 152 of each machining unit 101, 102. As shown in FIG. 5 to be described later, the power source 29 supplies a first machining power supply unit 29R that supplies electric discharge machining power to the first machining unit 101 and an electric discharge machining power to the second machining unit 102. And a second machining power supply unit 29L.

As shown in FIG. 1, the guide roller 24F is rotationally driven by a draw motor 25C, and the work feed units 27A and 27B are driven by stepping motors 25EA and 25EB, respectively. Further, the first machining unit 101 and the second machining unit 102 of the multi-wire electric discharge machining apparatus 100 are respectively a position sensor 31 that detects the position of the dancer roll 12, and a break detection sensor 32 that detects a break in the wire. It has. The feed motor 25A, the speed motor 25B, the draw motor 25C, the torque motor 25D, and the take-up motor 25H of each processing unit 101 and 102 have a built-in rotary encoder and can output the number of rotations. It is a motor. Further, the positioning motors 25F and 25G of the machining units 101 and 102 can detect the rotation angle of the internal rotor, and the guides 17 and wires of the machining units 101 and 102 are determined from the rotation angle of the rotor. The position of the alignment unit 21 can be detected. Also, the workpiece feeding units 27A and 27B are connected to the ingots 28A and 28B in the direction orthogonal to the feeding direction of the wires 151 and 152 at the cutting wire portions 261A, 261B, 262A and 262B of the machining units 101 and 102, respectively. Are configured to be movable, and are configured to be driven by the stepping motors 25EA and 25EB. Each stepping motor 25EA, 25EB can detect the rotation angle of the internal rotor, and can detect the position of each ingot 28A, 28B from the rotation angle of the rotor. The positive output lines 295R and 295L of the machining power supply units 29R and 29L of the power supply 29 are connected to the ingots 28A and 28B from the common positive output line 295 by the ingot connection lines 295A and 295B, respectively. Each rotation of the first processing unit 101 by the first rotating electrode connection lines 296A ₁ , 296B ₁ , 296C ₁ and the second rotating electrode connection lines 296A ₂ , 296B ₂ , 296C ₂ branched from 296R, 296L, respectively. The electrodes 200A ₁ , 200B ₁ , 200C ₁ are connected to the rotating electrodes 200A ₂ , 200B ₂ , 200C ₂ of the _second processing unit 102, and the rotating electrodes 200A _{1 of the} ingots 28A, 28B and the processing units 101, 102 are connected. _{, 200B 1, 200C 1, 200A} 2, 200B 2, 200C 2 It is configured to feed each discharge machining power of each processing unit 101, 102 during the.

In the multi-wire electric discharge machining apparatus 100 of the present embodiment, the electric conductivity of each of the ingots 28A and 28B and the rotary electrodes 200A ₁ , 200B ₁ , 200C ₁ , 200A ₂ , 200B ₂ , and 200C ₂ of the machining units 101 and 102 is high. It is immersed in the adjusted pure water or oil-based processing fluid, and the discharge between each cutting wire portion 261A, 262A, 261B, 262B of each processing unit 101, 102 and each ingot 28A, 28B is performed in water. In other words, the temperature rise of the entire ingots 28A and 28B can be suppressed during processing. Further, the temperature of the entire ingot 28 being processed is controlled by water splashing between the cutting wire portions 261 and 262 of the processing units 101 and 102 and pure water or oil-based processing fluid with adjusted electrical conductivity. It is also possible to suppress the rise.

  A feed bobbin 10A of each processing unit 101, 102, a feed motor 25A that rotates the take-up bobbin 10B, a take-up motor 25H, a speed motor 25B that rotates the speed pulley 16, and a draw motor 25C that rotates the guide roller 24F; The torque motor 25D for rotating the tension pulley 18, the stepping motors 25EA and 25EB, the positioning motors 25F and 25G, and the power source 29 are connected to the control unit 80 and are configured to operate according to commands from the control unit 80. In addition, the first and second wire tension sensors 13A and 13B of the processing units 101 and 102, the position sensor 31 that detects the position of the dancer roll 12, and the disconnection detection sensor 32 that detects the disconnection of the wire 15 are controlled. The detection signal is connected to the control unit 80 and input to the control unit 80. The control unit 80 is a computer that includes an internal signal processing CPU and a memory that stores control programs and data. When the disconnection of the first wire 151 and the second wire 152 is detected by the disconnection detection sensor 32 provided in each of the machining units 101 and 102, the control unit 80 operates the multi-wire electric discharge machining apparatus 100. Stop.

As shown in FIG. 2, in the multi-wire electric discharge machining apparatus 100 configured as described above, when the first wire 151 of the first machining unit 101 is sent in the direction of the arrow R in the drawing, the guide rollers 24 </ b> A˜ 24H, each rotating electrode 200A ₁ , 200B ₁ , 200C ₁ , each idle roller 300A ₁ , 300B ₁ , 300C ₁ has a surface on which the first wire 151 is wound or a surface on which the first wire 151 is in contact. Each guide roller 24A, rotating electrode 200A ₁ , each guide roller 24B, 24G, rotating electrode 200C ₁ , each guide roller 24H, 24C, rotating electrode 200B ₁ , so as to be in the same direction as the feed direction of the first wire 151 The guide roller 24D has rotating shafts 124A, 203A, 124B, 124G, 203C, 124H, 124C, 203B, respectively. Rotated clockwise around 124D, each idle roller 300A _1, 300B _1, respectively 300C ₁ is the rotation axis 301A, 301B, it rotates in the counterclockwise around 301C. The guide rollers 24A to 24D, 24G, 24H, each idle roller 300A _1, 300B _1, 300C ₁ is a fluorine-based material, nylon-based materials, high dielectric materials such as ceramics abrasion resistance is used. In addition, the cylindrical electrode members 201A ₁ , 201B ₁ , 201C ₁ of the rotating electrodes 200A ₁ , 200B ₁ , 200C ₁ are made of copper alloy such as copper, copper tungsten, etc. having high electrical conductivity, silver alloy such as silver tungsten, etc. Material is used. Since the cylindrical electrode members 201A ₁ , 201B ₁ , 201C ₁ of the rotating electrodes 200A ₁ , 200B ₁ , 201C ₁ rotate so that their peripheral speeds are substantially the same as the feed speed of the first wire 151, When the relative speed with respect to the first wire 151 is substantially zero, there is no friction between the wire and the electrode as in a conventional fixed electrode, and a material such as copper having high electrical conductivity is used. However, it is suppressed that the surface is worn. Each electrode member 201A _1, 201B _1, 201C ₁ and the first wire 151 and the electrode member 201A because there is no slippage ₁ between the first wire 151, 201B _1, instantaneously between 201C ₁ it is suppressed that discharge between the first wire 151 a gap between each electrode member 201A _1, 201B _1, 201C ₁ occurs, the electrode members 201A ₁ by a first wire 151, 201B _1, 201C It is suppressed that ₁ is shaved. FIG. 2 shows the winding of the first wire 151 of the first processing unit 101, the guide rollers 24A to 24H, the rotary electrodes 200A ₁ , 200B ₁ , 200C ₁ , the idle rollers 300A ₁ , 300B ₁ , 300C ₁ . Although the rotation has been described, the rotating electrodes 200A ₂ , 200B ₂ , and 200C _{2 of} the second processing unit 102 (not shown) also rotate clockwise around the common rotating shafts 203A, 203B, and 203C, respectively, and each idle roller 300A. ₂ , 300B ₂ and 300C ₂ also rotate counterclockwise around the common rotating shafts 301A, 301B and 301C, respectively. The guide rollers 24A-24H, each idle roller 300A _2, 300B _2, 300C ₂ is likewise a fluorine-based material, nylon-based materials, high dielectric materials such as ceramics abrasion resistance is used, rotating electrode 200A _2, 200B ₂ , 200C ₂ cylindrical electrode members 201A ₂ , 201B ₂ , and 201C ₂ are made of a material having high electrical conductivity such as copper, a copper alloy such as copper tungsten, or a silver alloy such as silver tungsten. The cylindrical electrode members 201A ₂ , 201B ₂ , and 201C ₂ of the rotary electrodes 200A ₂ , 200B ₂ , and 200C ₂ of the second processing unit 102 have a circumferential speed that is substantially the same as the feed speed of the second wire 152. Therefore, the relative speed with respect to the second wire 152 is also substantially zero, and there is no friction between the wire and the electrode as in the conventional fixed electrode, and the copper having high electrical conductivity. Even when such a material is used, the surface is prevented from being worn.

Each ingot 28A of silicon carbide (silicon carbide) in the multi-wire electric discharge machining apparatus 100 having first, second upper and lower cutting wire portions 261A, 261B, 262A, 262B composed of a plurality of wires 151, 152 , 28B, silicon carbide components adhere to the surface of the wire as powder 70 each time the battery is discharged. As shown in FIG. 3, in the electric discharge machining of the first machining unit 101, each ingot 28A, 28B is performed while being fed toward the first upper and lower cutting wire portions 261A, 261B. Electric discharge with each ingot 28A, 28B often occurs between each ingot 28A, 28B side of the first wire 151 and the machining groove 28a of each ingot 28A, 28B. For this reason, the silicon carbide powder 70 scattered by the electric discharge machining mainly adheres to the surfaces of the first wires 151 on the ingots 28A and 28B side. Accordingly, in the present embodiment, the surface of the first wire 151 opposite to the ingots 28A and 28B to which the silicon carbide powder 70 is less adhered is provided on the surface of each electrode member 201A ₁ , 201B ₁ , 201C _1. The rotating electrodes 200A ₁ , 200B ₁ , and 200C ₁ are disposed so as to be in contact with 206A ₁ , 206B ₁ , and 206C ₁ . For this reason, it is suppressed that the silicon carbide powder 70 adhered to the first wire 151 by the electric discharge machining contacts the grooves 206A ₁ , 206B ₁ , 206C ₁ of the electrode members 201A ₁ , 201B ₁ , 201C _1. The wear of the grooves 206A ₁ , 206B ₁ , 206C _{1 of} 201A ₁ , 201B ₁ , 201C ₁ is suppressed. Thus, even when long-time electric discharge machining is performed, such as when slicing a hard material such as silicon carbide having a large diameter, the electric discharge machining power can be stably applied to the first wire 151 without complicated replacement of the electrodes. Can be fed to perform electric discharge machining. The first processing unit 101 has been described with reference to FIG. 3, but the same applies to the second processing unit 102.

As shown in FIG. 2, in the first machining unit 101 of the multi-wire electric discharge machining apparatus 100 of the present embodiment, an idle roller 300A ₁ is arranged on the upstream side in the wire feeding direction indicated by the arrow R of the rotary electrode 200A _1. The guide roller 24B constituting the first upper cutting wire portion 261A is disposed downstream of the rotating electrode 200A _{1 in} the wire feeding direction, and the idle roller 300A ₁ is a _first electrode to the electrode member 201A ₁ of the rotating electrode 200A 1. The winding angle of the wire 151 is arranged to be an angle θ ₁ (rad). In this case, if the diameter of the electrode member 201A ₁ is D, the first wire 151 contacts the electrode member 201A ₁ by a length of (θ ₁ × D / 2). Further, since it is under tension T in the first wire 151, the tension _{T, F 1 = 2 × T} × sin (θ 1/2), the first wire 151 is electrode member 201A by the force of only Pressed against _one surface. Rotating electrode 200B ₁ is similar. As described above, the rotary electrodes 200A ₁ and 200B ₁ according to the present embodiment can increase the contact length between the electrode members 201A ₁ and 201B ₁ and the first wire 151, and the first wire 151 is connected to the electrode member 201A. ₁ and 201B ₁ are pressed. The rotating electrode 200C ₁ holds the contact force between the _first wire 151 and the electrode member 201C ₁ by sandwiching the first wire 151 between the rotating roller 200C _{1 and} the idle roller 300C ₁ . Therefore, electric discharge machining power each electrode member 201A _1, 201B _1, 201C ₁ from the electrical resistance or impedance is small when supplying power to each row of the first wire 151, supplies electric discharge machining power without decreasing the voltage can do. Each rotating electrode 200A ₁ , 200B ₁ , 200C ₁ rotates in the same direction as the feeding direction of the first wire 151, so that each electrode member 201 A ₁ , 201 B ₁ , 201 C ₁ and the first wire 151 The first wire 151 is contacted with almost no relative velocity. For this reason, even when a material such as copper having high electrical conductivity is used for each electrode member 201A ₁ , 201B ₁ , 201C ₁ , the contact state is good and the surface is worn even when the first wire 151 is pressed. without having to first wire 151 and the respective electrode members 201A _1, 201B _1, 201C ₁ first wire 151 and the respective electrode members 201A and instantaneously a gap between the _1, 201B _1, 201C ₁ Is prevented from being generated, and the electrode members 201A ₁ , 201B ₁ , 201C ₁ are prevented from being scraped. For this reason, electric discharge machining power can be supplied to the first wire 151 stably for a long time, and electric discharge machining can be performed. In addition, it is possible to supply power to the first wire 151 without reducing the voltage of the electric discharge machining power supplied from the power source 29, and it is possible to suppress a reduction in the electric discharge machining speed. The contact between the first wire 151 of the first processing unit 101 and the electrode members 201A ₁ , 201B ₁ , 201C ₁ has been described above with reference to FIG. 2, but the second of the second processing unit 102 The same applies to the contact between the wire 152 and each electrode member 201A ₂ , 201B ₂ , 201C ₂ .

In addition, as shown in FIG. 2, the first upper cutting wire portion 261A and the first lower cutting wire portion 261B of the first processing unit 101 are each of the center line 101C in the Y direction of the first processing unit 101. The rotating electrodes 200C ₁ of the first processing unit 101 are arranged symmetrically in the vertical direction at a distance X _{2 in} the X direction from the first upper and lower cutting wire portions 261A and 261B on the center line 101C. The idle roller 300C ₁ is disposed so as to face the rotating electrode 200C ₁ so that the first wire 151 can be sandwiched between the rotating roller 200C ₁ on the center line 101C. A straight first wire 151 between two adjacent guide rollers 24B and 24G having the same diameter in the first processing unit 101 constitutes a plurality of first upper cutting wire portions 261A, and the guide rollers 24H and 24D The straight first wire 151 in between constitutes a plurality of first lower cutting wire portions 261B. The height Y ₁ between the lower end of the guide roller 24B and the upper end of 24G is the length of the first upper cutting wire portion 261A, and the height Y ₁ between the lower end of the guide roller 24H and the upper end of 24D. Is the length of the first lower cutting wire portion 261B. The center in the Y direction (vertical direction) of the first upper cutting wire portion 261A is the center 26CA ₁ , and the center in the Y direction (vertical direction) of the first lower cutting wire portion 261B is the center 26CB _1. The centers 26CA ₁ and 26CB ₁ are arranged at a distance Y ₃ symmetrically in the Y direction from the center line 101C of the first processing unit 101. The rotating electrode 200A ₁ disposed on the upstream side of the first wire 151 of the first upper cutting wire portion 261A has a rotation center 205A (rotating shaft 203A) as the center 26CA _{1 of} the first upper cutting wire portion 261A. From the center line 101C of the first processing unit 101 at the position of X _{1 in} the X direction (lateral direction) and Y ₂ on the plus side of the Y direction, and the position of Y _{4 in} the plus direction. The rotating electrode 200B ₁ disposed on the downstream side of the first wire 151 of the lower cutting wire portion 261B has a rotation center 205B (rotating shaft 203B) in the X direction from the center 26CB _{1 of} the first lower cutting wire portion 261B. It is arranged so that it is located at the position of Y _{4 in} the plus direction from the center line 101C of the first processing unit 101 at the position of X _{1 in} the (lateral direction) and Y ₂ on the minus side of the Y direction. Further, the idle rollers 300A ₁ and 300B ₁ are respectively symmetrical with respect to the Y direction from the center line 101C of the first processing unit 101, and the centers 26CA of the first upper and lower cutting wire portions 261A and 261B. _1, are arranged equidistant from each 26CB _1. That is, the rotary electrodes 200A ₁ , 200B ₁ , 200C ₁ idle rollers 300A ₁ , 300B ₁ , 300C ₁ , guide rollers 24A to 24D, 24G, 24H are arranged symmetrically above and below the center line 101C of the first processing unit 101. Has been.

Also, a distance along the first wire 151 from the rotary electrode 200C ₁ to the center 26CA ₁ of the first upper cutting wire portion 261A, the rotary electrode 200A ₁ to the center 26CA ₁ of the first upper cutting wire portion 261A The distance along the first wire 151 is the same as the distance along the first wire 151 from the rotating electrode 200C ₁ to the center 26CB ₁ of the first lower cutting wire portion 261B, and the rotating electrode 200B. _The distance along the first wire 151 from ₁ to the center 26CB ₁ of the first lower cutting wire portion 261B is the same, from the rotating electrode 200C ₁ to the center 26CA _{1 of} the first upper cutting wire portion 261A. the first wire 151 of the distance along the first wire 151, the rotary electrode 200C ₁ to the center 26CB ₁ of the first lower cutting wire portion 261B As the along distance is the same, the distance _{X 1, X 2, Y 2} , Y 3, Y 4 is selected. Accordingly, the rotary electrodes 200A ₁ and 200C ₁ are arranged at the same distance from the center 26CA ₁ of the first upper cutting wire portion 261A along the path around which the first wire 151 is wound, and the first upper cutting wire portion The electric discharge machining power can be evenly supplied to 261A, and each of the rotating electrodes 200B ₁ and 200C ₁ is routed from the center 26CB ₁ of the first lower cutting wire portion 261B to the path around which the first wire 151 is wound. The electric discharge machining power can be evenly supplied to the first lower cutting wire portion 261B. When cutting the ingots 28A and 28B, the centers 28CA and 28CB of the cylindrical ingots 28A and 28B are used as the centers 26CA ₁ and 26CB in the Y direction of the first upper and lower cutting wire portions 261A and 261B. ₁ is sent along the center lines 28DA and 28DB extending in the feed direction of the ingots 28A and 28B through the centers 26CA ₁ , 26CB ₁ , 28CA and 28CB. The upper and lower portions of the ingots 28A and 28B can be processed equally. The arrangement of the rotary electrodes 200A ₁ and 200B ₁ of the first processing unit 101 has been described above with reference to FIG. 2, but the same applies to the second processing unit 102.

A support structure for the rotating electrodes 200A ₁ and 200A ₂ of the multi-wire electric discharge machining apparatus 100 of the present embodiment will be described with reference to FIG. As shown in FIG. 4 (a), the rotating electrodes 200A ₁ and 200A ₂ of the first machining unit are attached to the base of the multi-wire electric discharge machining apparatus 100 and fixed to a non-rotating base 250A. Electrode members 201A ₁ and 201A ₂ are attached to the outer periphery of the insulating shaft 203A via _two conductive bearings 202A ₁ and 202A ₂ , respectively. The electrode members 201A ₁ and 201A ₂ are cylindrical conductors made of a material such as copper having good electrical conductivity. The conductive bearings 202A ₁ and 202A ₂ are made of metal inner rings 211A ₁ and 211A ₂ fixed to the outer periphery of the insulating shaft 203A, and metal outer rings 212A ₁ fitted into the inner surfaces of the electrode members 201A ₁ and 202A ₂ , respectively. 212A ₂ and metal balls 213A ₁ and 213A ₂ that are sandwiched between inner rings 211A ₁ and 211A ₂ and outer rings 212A ₁ and 212A ₂ and arranged circumferentially. Further, conductive grease 214A ₁ and 214A ₂ are filled between the inner rings 211A ₁ and 211A ₂ and the outer rings 212A ₁ and 212A ₂ . Stepped portion 210A also has a larger diameter than the portion on the base 250A which is mounted a conductive bearings 202A ₁ of the insulating shaft 203A is provided. A metal collar 208A is fitted between the step portion 210A and the inner ring 211A _{1 of the one} conductive bearing 202A ₁ , and the base portion 250A side end of the collar 208A and the step portion 210A are disposed later. first feeding terminal 220A ₁ is connected to be connected to a first machining power supply unit 29R of the power supply 29 described with reference to FIG. 5, the opposite end is the one conductive base 250A of metal collar 208A The bearing 202A ₁ is connected to the inner ring 211A ₁ . Between the inner ring 211A ₁ of the other conductive bearings 202A _1, and metal collar 208A ₁ are attached shorter than color 208A, 2 two inner races 211A ₁ of the conductive bearings 202A ₁ is The metal collars 208A and 208A ₁ are electrically connected to the first power supply terminal 220A ₁ . The metal collars 208A and 208A ₁ and the first power supply terminal 220A ₁ constitute a first power supply member.

A metal conductive shaft 204A is fitted in the center of the insulating shaft 203A. Then, the ends of the base 250A side of the conductive shaft 204A is connected to a second power supply terminal 220A ₂ is connected to the later second machining power unit 29L of the power supply 29 described with reference to FIG. 5 . Further, the end portion of the substrate 250A opposite the conductive shaft 204A are attached end ring 208A ₃ metallic. The outer peripheral side of the end ring 208A ₃ are connected insulated is fitted on the outer periphery of the shaft 203A, the end surface in the axial direction on the inner ring 211A ₂ of one conductive bearings 202A _2. In addition, between the two inner races 211A ₂ of the conductive bearings 202A ₂ are electrically connected by the collar 208A ₂ metallic, inner races 211A ₂ of the two conductive bearings 202A ₂ are color 208A ₂ And the end ring 208A ₃ is connected to the _second power supply terminal 220A ₂ . Metal collar 208A ₂ and the end ring 208A ₃ and the conductive shaft 204A and the second feeding terminal 220A ₂ constitutes a second power supply member.

Further, in the outer periphery of the insulating shaft 203A, a cylindrical spacer 209 formed of an insulating material is attached between the inner ring 211A ₁ of the inner ring 211A ₁ and the conductive bearing 202A ₁ of the conductive bearings 202A ₁ adjacent to each other The rotary electrodes 200A ₁ and 200A ₂ adjacent to each other are electrically insulated from each other.

The electric current of the electric discharge machining power input from the first power supply terminal 220A ₁ passes through the inner ring 211A ₁ , the ball 213A ₁ and the outer ring 212A ₁ of the two conductive bearings 202A ₁ from the metal collars 208A and 208A _1. reached member 201A _1, flows into each row of the first wire 151 in contact with the groove 206A ₁ provided on the outer surface of the electrode member 201A _1. Since the conductive grease 214A ₁ is filled between the inner ring 211A ₁ and the outer ring 212A ₁ of the conductive bearing 202A ₁ , the current flowing through the inner ring 211A ₁ flows through the conductive grease 214A _1. reached the outer ring 212A ₁ Te reaches the outer ring 212A ₁ the electrode member 201A _1. The second feeding terminal 220A of discharge machining power inputted from the _second current, the conductive shaft 204A, a metal end ring 208A _3, the inner ring 211A ₂ from color 208A ₂ 2 one conductive bearings 202A _2, the ball 213A _2, through the outer ring 212A ₂ reaches the electrode member 201A _2, flows into each row of the second wire 152 in contact with the groove 206A ₂ provided on the outer surface of the electrode member 201A _2. Since the conductive grease 214A ₂ is filled between the inner ring 211A ₂ and the outer ring 212A ₂ of the conductive bearing 202A ₂ , the current flowing through the inner ring 211A ₂ flows through the conductive grease 214A _2. And reaches the outer ring 212A ₂ and reaches the electrode member 201A ₂ from the outer ring 212A ₂ .

Thus, since the conductive bearings 202A ₁ and 202A ₂ are configured to have low electrical resistance or impedance, they reach the rotating electrode members 201A ₁ and 201A ₂ from the power supply terminals 220A ₁ and 220A _2. It has a structure with little voltage drop of electric discharge machining power.

As shown in FIG. 4B, V-shaped grooves 206A ₁ and 206A ₂ for winding the first wire 151 and the second wire 152 are provided on the outer surfaces of the electrode members 201A ₁ and 201A ₂ , respectively. The intervals between the grooves 206A ₁ and 206A ₂ are the same as the pitch between the wires 151 and 152, respectively. Also, the distance between the first wire 151 at the left end of the electrode member 201A ₁ in FIG. 4A and the second wire 152 at the right end of the electrode member 201A ₂ in FIG. Thus, each strip of the first wire 151 and each strip of the second wire 152 are arranged at equal intervals of the pitch P.

In the above embodiment, the grooves 206A ₁ and 2006A ₂ provided on the outer surfaces of the electrode members 201A ₁ and 201A ₂ have been described as being V-shaped, but as shown in FIG. Semicircular grooves 207A ₁ and 207A ₂ along the outer surface of 152 may be used. In this case, to support a plane rather than each wire 151 and 152 lines, and reduce the load of each wire 151 and 152 by being wound around the rotating electrode 200A _1, 200A _2, each wire 151 and 152 Can be suppressed.

In the embodiment described above, each of the first processing unit 101 in which one first wire 151 is wound around a plurality of strips and the second processing unit in which one second wire 152 is wound around the plurality of strips. Although it has been described that the two machining units 102 and 102 are arranged in parallel on the left and right, the number of machining units is not limited to two, and one wire is wound around a plurality of strips. One or four or more processing units may be arranged adjacent to each guide roller, each rotating electrode, and each rotation axis of each idle roller of each processing unit. In the present embodiment, each idle roller 300A ₁ , 300B ₁ , 300C ₁ of the first processing unit 101 is different from each idle roller 300A ₂ , 300B ₂ , 300C _{2 of} the second processing unit 102. Although it has been described that the members are disposed adjacent to each other on the same axis along the rotation axis direction and electrically insulated from each other, the idle rollers 300A ₁ , 300B ₁ , 300C ₁ , 300A ₂ , 300B are described. ₂ and 300C ₂ may not be separate members, and adjacent members may be integrally disposed around the respective rotation shafts 301A, 301B, and 301C.

  With reference to FIG. 5, the configuration and operation of a power supply 29 for electric discharge machining used in the multi-wire electric discharge machining apparatus 100 of the present embodiment will be described. As shown in FIG. 5, the power supply 29 includes a first machining power supply unit 29 </ b> R that supplies electric discharge machining power to the first machining unit 101, and a second machining that supplies electric discharge machining power to the second machining unit 102. Power supply unit 29L.

The first machining power unit 29R includes a main DC power source 292a _1, are the main DC power source 292a connected to _one series, the main switching transistor 291a ₁ which turns on and off the output of the main DC power source 292a _1, a main DC power source 292a ₁ in parallel, its voltage plus or minus direction in reverse the sub DC power supply 294a ₁ lower than the main DC power source 292a _1, is connected to the secondary DC power source 294a ₁ in series, secondary turns on and off the output of the auxiliary DC power source 294a ₁ Switching transistor 293a ₁ . Each gate of each of the switching transistors 291a ₁ and 293a ₁ is connected to the control unit 80, and is configured to be turned on / off by a command from the control unit 80. The plus side of the main DC power source 292a ₁ is connected positive side output line 295R, and the minus side of the main DC power source 292a ₁ is connected the negative side output line 296R. The plus side output line 295R is connected from the common plus side output line 295 to the ingots 28A and 28B via the ingot connecting lines 295A and 295B, and the minus side output line 296R is the three rotating electrode connecting lines of the first machining unit. 296A ₁ , 296B ₁ , and 296C ₁ are branched, the rotating electrode connecting line 296A ₁ is connected to the rotating electrode 200A ₁ , the rotating electrode connecting line 296B ₁ is connected to the rotating electrode 200B ₁ , and the rotating electrode connecting line 296C ₁ is rotated. It is connected to the electrode 200C _1. Accordingly, the first machining power unit 29R each rotating electrode 200A _1, 200B _1, a common power source 200C _1, each rotating electrode 200A _1, 200B _1, first the 200C ₁ common first machining power supply unit 29R Are supplied with the same electric discharge machining power.

The second machining power supply unit 29L has the same configuration as the first machining power supply unit 29R, and is connected in series with the main DC power supply 292a ₂ and the main DC power supply 292a _2, and the output of the main DC power supply 292a ₂ a main switching transistor 291a ₂ for permitting and blocking, the main DC power source 292a ₂ and parallel, plus or minus directions its voltage in the reverse and the sub DC power supply 294a ₂ lower than the main DC power source 292a _2, the sub DC power supply 294a ₂ And a sub-switching transistor 293a ₂ connected in series to turn on and off the output of the sub-DC power supply 294a ₂ . Each gate of each of the switching transistors 291a ₂ and 293a ₂ is connected to the control unit 80, and is configured to be turned on / off by a command from the control unit 80. The plus side of the main DC power source 292a ₂ is connected to the positive side output line 295L, and the minus side of the main DC power source 292a ₂ is connected to the negative side output line 296L. The plus side output line 295L is connected from the common plus side output line 295 to the ingots 28A and 28B via the ingot connecting lines 295A and 295B, and the minus side output line 296L is the three rotating electrode connecting lines of the second machining unit. 296A ₂ , 296B ₂ , and 296C ₂ , the rotating electrode connection line 296A ₂ is connected to the rotating electrode 200A ₂ , the rotating electrode connecting line 296B ₂ is connected to the rotating electrode 200B ₂ , and the rotating electrode connecting line 296C ₂ rotates. It is connected to the electrode 200C _2. Accordingly, the second machining power unit 29L is a common power source to each rotating electrode 200A _2, 200B _2, 200C _2, the common first machining power unit 29L to each rotating electrode 200A _2, 200B _2, 200C ₂ Are supplied with the same electric discharge machining power.

As shown in FIG. 5, the first machining power supply unit 29R and the second machining power supply unit 29L are controlled by a common control unit 80, but the switching transistors 291a ₁ and 293a of the first machining power supply unit 29R are controlled. _The switching transistors 291a ₂ and 293a ₂ of the _first processing power unit 29L and the second processing power supply unit 29L operate independently of the processing power supply units 29R and 29L, respectively, and the first processing unit 101 and the second processing power unit 102 include Electric discharge machining power is supplied at independent timings. The switching transistors 291a ₁ , 293a _{1 of} the first machining power supply unit 29R and the switching transistors 291a ₂ , 293a ₂ of the second machining power supply unit 29L may operate so as to be turned on / off in synchronization with each other. You may make it operate | move by shifting the on-off period without synchronizing.

The electric discharge machining power supplied from the first machining power supply unit 29R to the first machining unit 101 will be described with reference to FIG. As shown in FIG. 6, the electric discharge machining power includes an electric discharge machining pulse 297 for performing electric discharge machining, and an electric discharge machining pulse 297 for removing residual charges remaining in capacitors and the like in the power supply system after electric discharge machining. The high-frequency pulse 299 including the residual charge neutralizing pulse 298. The high-frequency pulse 299 is obtained by operating the switching transistors 291a ₁ and 293a ₁ of the first machining power supply unit 29R as follows. Initially, the switching transistors 291a ₁ and 293a ₁ are turned off, and no output is output from the first machining power supply unit 29R. When the main switching transistor 291a ₁ is turned on at time t ₁ in FIG. 6, a current from the main DC power supply 292a ₁ is output from the plus side output line 295R, and the ingots 28A and 28B and the rotating electrodes 200A ₁ and 200B ₁ , The voltage V ₁ of the electric discharge machining pulse 297 is applied between 200C ₁ . Then, after the main switching transistor 291a ₁ is kept on only for the time Δt ₁ , the main switching transistor 291a ₁ is turned off at time t ₂ in FIG. Then, the current from the main DC power supply 292a ₁ output from the plus side output line 295R stops, and the applied voltage between each ingot 28A, 28B and each rotary electrode 200A ₁ , 200B ₁ , 200C ₁ becomes zero. The electric discharge machining pulse 297 stops. Then, after the applied voltage is held at zero for a predetermined time Δt ₂ , the current from the sub DC power supply 294a ₁ is output from the negative output line 296R when the sub switching transistor 293a ₁ is turned on at time t _3. Then, a residual charge neutralizing pulse 298 having a negative voltage V ₂ is applied between the ingots 28A and 28B and the rotating electrodes 200A ₁ , 200B ₁ , and 200C ₁ . Then, after the on state of the sub switching transistor 293a ₁ is continued only for the time Δt ₃ , the sub switching transistor 293a ₁ is turned off at the time t ₄ in FIG. Then, the current from the sub DC power supply 294a ₁ output from the negative output line 296R is stopped, and the applied voltage between each ingot 28A, 28B and each rotary electrode 200A ₁ , 200B ₁ , 200C ₁ becomes zero. The residual charge neutralizing pulse 298 is stopped. After the residual charge neutralization pulse 298 is stopped, the main switching transistor 291a ₁ is turned on again at time t ₅ after time Δt ₄ . In this way, the main switching transistor 291a ₁ and the sub-switching transistor 293a ₁ are alternately turned on and off to output the positive side high-voltage electric discharge machining pulse 297 and the negative side low-voltage residual charge neutralizing pulse 298. As shown in FIG. 6, the period of the high-pressure electric discharge machining pulse 297 is Δt ₀ , and the frequency thereof is a high frequency of several tens kHz to several hundreds kHz. The frequency of the low-voltage residual charge neutralizing pulse 298 is the same as the frequency of the high-voltage electric discharge machining pulse 297. In FIG. 6, after the stop of the residual charge neutralization pulse 298, the time Delta] t ₄ after time t ₅ again, although the main switching transistor 291a ₁ has been described that turned on, immediately after stop of the residual charge neutralization pulse 298 Again, the main switching transistor 291a ₁ may be turned on. In this case, the period of the high-pressure electric discharge machining pulse 297 can be set to a higher frequency electric discharge machining pulse 297 because Δt ₀ becomes shorter, and the electric discharge machining speed can be increased. The case where the electric discharge machining power is supplied from the first machining power supply unit 29R to the first machining unit 101 has been described above, but the electric discharge machining power supplied from the second machining power supply unit 29L to the second machining unit 102 has been described. This is also the same as the case where electric discharge machining power is supplied from the first machining power supply unit 29R to the first machining unit 101.

In the present embodiment, the main DC power source 292a _1, 292a _2, each sub DC power supply 294a _1, 294a ₂ has been described as a simple DC power source such as a battery, voltages V ₁ or residual charge neutralization pulse discharge machining pulse 297 As long as the voltage V ₂ of 298 can be supplied, for example, power may be stored using a capacitor or a transformer, and the stored power may be supplied as DC power.

The multi-wire electric discharge machining apparatus 100 according to the present embodiment has the structure described with reference to FIGS. 1 to 4 and includes the power supply 29 for electric discharge machining described with reference to FIGS. 5 and 6. The operation will be described with reference to FIG. FIG. 7 shows the rotating electrodes 200A ₁ , 200B ₁ , 200C ₁ of the first processing unit 101, the rotating electrodes 200A ₂ , 200B ₂ , 200C _{2 of} the second processing unit 102, the ingots 28A, 28B, It is the figure which represented typically the electrical connection state of the process power supply unit 29R and the 2nd process power supply unit 29L. The adjacent rotary electrodes 200A ₁ , 200B ₂ , 200C ₂ and the rotary electrodes 200B ₁ , 200B ₂ , 200C ₂ are electrically insulated, and the rotary electrodes 200A ₁ , 200B _{1 of} the first processing unit 101 are electrically insulated. , 200C ₁ is connected to one negative output line 296R, and each rotary electrode 200A ₂ , 200B ₂ , 200C _{2 of} the second processing unit 102 is also connected to one negative output line 296L. The rotating electrodes 200A ₁ , 200B ₁ , 200C ₁ , 200A ₂ , 200B ₂ , and 200C ₂ of the processing units 101 and 102 are common to the strips of the first wire 151 and the strips of the second wire 152, respectively. Electrode. Further, the rotary electrodes 200A ₁ and 200C ₁ of the first processing unit 101 are arranged so that the distances L _A and L _B to the center 26CA ₁ of the first upper cutting wire portion 261A are the same, and the first processing unit 101 has the first processing. rotary electrode 200B _1, 200C ₁ unit 101 is arranged so that the distance L _a to the center 26CB ₁ of the first lower cutting wire portion 261B, the L _B become the same, each ingot 28A, 28B is Since the center moves in the feed direction within the plane including the centers 26CA ₁ and 26CB ₁ of the first upper and lower cutting wire portions 261A and 261B, the rotation of the ingot 28A from the rotating electrodes 200A ₁ and 200C ₁ The distance to the center and the distance from each of the rotating electrodes 200C ₁ and 200B ₁ to the center of the ingot 28B are also the same. Accordingly, the same electric discharge machining pulse 297 and the residual charge discharging pulse 298 are provided between the first upper cutting wire portion 261A and the ingot 28A and the first lower cutting wire portion 261B and the ingot 28B of the first machining unit 101. Are simultaneously applied from three locations of each strip of the first wire 151. The first processing unit 101 has been described above, but the same applies to the second processing unit 102.

As shown in FIG. 7, when an electric discharge machining pulse 297 is input from the first machining power supply unit 29R to the ingots 28A and 28B, the first upper and lower cutting wires are passed through the rotating electrodes 200A ₁ , 200B ₁ , and 200C ₁ . The same electric discharge machining pulse 297 is applied between the portions 261A and 261B and the ingots 28A and 28B. Since the rotating electrodes 200A ₁ , 200B ₁ , and 200C ₁ are configured to have a low electric resistance or impedance, even when such a high-frequency electric discharge machining pulse 297 is applied, the voltage is not lowered and the first voltage is not reduced. An electric discharge machining pulse 297 is applied between the upper and lower cutting wire portions 261A and 261B of 1 and the ingots 28A and 28B. When one electric discharge machining pulse 297 is applied, the electric discharge is generated between the portion of the first upper cutting wire portion 261A entering the ingot 28A and the ingot 28A, or the first lower cutting wire. This occurs only once in the portion 261B where the distance between the portion that enters the ingot 28B and the ingot 28B is the shortest. For example, when the electric discharge machining pulse 297 is input, the distance between the point a side of the first upper cutting wire portion 261A and the ingot 28A is different from the other first upper cutting wire portion 261A and the first lower cutting wire portion. If it is shorter than any of the distances between 261B and ingot 28B, the electric discharge occurs only between first upper cutting wire portion 261A and the vicinity of point a of ingot 28A, and the other first upper cutting wire portion. No discharge occurs between 261A and ingot 28A and between first lower cutting wire portion 261B and ingot 28B. In this case, current flows from the ingot 28A to the first upper cutting wire portion 261A, flows through the rotating electrode 200A ₁ which is disposed closer to a point of the ingot 28A. When the vicinity of the point a is cut by this electric discharge, the distance between the first upper cutting wire portion 261A and the ingot 28A in the vicinity of the point a becomes larger than the other portions, so the next electric discharge machining pulse 297 is applied. In some cases, the discharge is not near point a, for example, near point b of ingot 28A of other first upper cutting wire portion 261A or near point p of ingot 28B of first lower cutting wire portion 261B. Will occur. In this way, in the first machining unit 101, a discharge is generated only once each time a voltage is applied by one electric discharge machining pulse 297, and the discharge is caused by the first upper and lower cutting wire portions 261A and 261B and each ingot. Randomly occurs at the portion where the distance from 28A and 28B is closest. The first upper and lower cutting wire portions 261A and 261B can evenly cut the ingots 28A and 28B in the feed direction. The electric discharge machining of the ingots 28A and 28B of the first machining unit 101 has been described above, but the same applies to the second machining unit 102.

The first machining power supply unit 29R and the second machining power supply unit 29L respectively independently supply the electric discharge machining power to the rotary electrodes 200A ₁ , 200B ₁ , 200C ₁ , 200A ₂ , 200B of the first and second machining units. ₂ and 200C ₂ , the ingots 28A and 28B are provided on the first upper side of the first processing unit 101, the lower cutting wire portions 261A and 261B, and the second upper side and lower side of the second processing unit 102, respectively. The cutting wire portions 262A and 262B are cut in substantially the same manner. Then, each of the ingots 28A, 261A, 262B on the first upper side of the first processing unit 101, the lower cutting wire portions 261A, 261B and the second upper side, lower cutting wire portions 262A, 262B of the second processing unit 102, respectively. When 28B is cut and the cutting is completed, a plurality of thin sheets of silicon carbide (silicon carbide) can be manufactured in each of the processing units 101 and 102, respectively.

As described above, the multi-wire electric discharge machining apparatus 100 of the present embodiment uses the rotating electrodes 200A ₁ , 200B ₁ , 200C ₁ , 200A ₂ , 200B ₂ , and 200C _{2 as} well as the power supply terminals 220A ₁ and 220A. ₂ to each of the rotating electrodes 200A ₁ , 200B ₁ , 200C ₁ , 200A ₂ , 200B ₂ , 200C ₂ , electrode resistance 201A ₁ , 201B ₁ , 201C ₁ , 201A ₂ , 201B ₂ , 201C ₂ Thus, even if the high frequency pulse 299 is applied, the voltage can be applied between the cutting wire portions 261A, 261B, 262A, 262B and the ingots 28A, 28B without lowering the voltage. There is an effect that the processing can be performed stably for a long time. Each electrode member _{201A 1, 201B 1, 201C 1} , 201A 2, 201B 2, 201C 2 and since there is no sliding each wire 151 and 152 and the respective electrode members 201A ₁ between each wire 151 and 152, 201B ₁ , 201C ₁ , 201A ₂ , 201B ₂ , 201C ₂ , instantaneous gaps are formed between the wires 151 and 152 and the electrode members 201A ₁ , 201B ₁ , 201C ₁ , 201A ₂ , 201B ₂ , 201C ₂ , Between the electrode members 201A ₁ , 201B ₁ , 201C ₁ , 201A ₂ , 201B ₂ , and 201C ₂ is suppressed.

  In the present embodiment, the first and second machining power supply units are provided with a first machining unit 101 and a second machining unit 102, and each of the machining units 101 and 102 supplies electric discharge machining power independently. 29R, 29L, and each processing unit 101, 102 includes upper and lower cutting wire portions 261A, 261B, 262A, 262B, and the upper wire cutting portions 261A, 262A cut the ingot 28A. Since the lower wire cutting portions 261B and 262B can cut the ingot 28B, the first machining unit 101 and the second machining unit 102 can simultaneously cut the two ingots 28A and 28B. Can efficiently make many pieces of silicon carbide (silicon carbide) It is possible to manufacture the plate. In addition, since the long ingots 28A and 28B can be processed, the yield of thin plate manufacturing can be improved. In the present embodiment, the number of windings of the wires 151 and 152 of each processing unit 101 and 102 has been described as five, the number of strips is five, and each of the cutting wire portions 261 and 262 is five. The guide roller of the processing units 101 and 102 and the length of the rotating electrode in the rotation axis direction are increased, and the number of windings of the wires 151 and 152 of each processing unit 101 and 102 is several tens of times, the number of strips is several tens, The upper and lower cutting wire portions 261A, 261B, 262A, 262B can be applied to a multi-wire electric discharge machining apparatus having several tens or more, and in particular, are applied to the multi-wire electric discharge machining apparatus having such a large number of windings. Then, the effect becomes more remarkable. In the present embodiment, each processing unit 101, 102 has been described as including two upper and lower cutting wire portions 261A, 261B, 262A, 262B. However, each processing unit 101, 102 has three or A larger number of cutting wire portions may be arranged side by side in the longitudinal direction of each of the wires 151 and 152, and a rotating electrode may be arranged in the middle of each cutting wire portion. When more cutting wire portions are arranged in this manner, a larger number of ingots can be processed simultaneously, and the silicon carbide plate can be cut out efficiently.

  Each processing power supply unit 29R, 29L of the power supply 29 of the present embodiment is connected to a main DC power supply, a main DC power supply in series, one main switching transistor for turning on and off the output of the main DC power supply, and the main DC power supply. One sub-DC power supply in parallel with the power supply, the direction of plus and minus being reversed and its voltage being lower than that of the main DC power supply, and one sub-switching transistor connected in series with the sub-DC power supply and turning on and off the output of the sub-DC power supply However, each processing power supply unit 29R, 29L may be configured to include a plurality of main DC power supplies, main switching transistors, sub DC power supplies, and sub switching transistors. In this case, the number of main switching transistors and main DC power supplies may be the same as the number of sub switching transistors and sub DC power supplies, respectively, or the number of main switching transistors and main DC power supplies may be equal to the number of sub switching transistors and sub DC power supplies. It may be greater than the number of DC power supplies.

  In the present embodiment, two ingots 28A and 28B have been described as being sent simultaneously toward the first and second upper and lower cutting wire portions 261A, 262A, 261B and 262B, but the two ingots 28A and 28B are described. May be shifted in the feeding direction. For example, the ingot 28A is first fed toward the first and second upper cutting wire portions 261A and 262A, the ingot 28A is cut by about half, and the first and second upper cutting wire portions 261A and 262A are cut from the ingot 28A. If the ingot 28B enters the vicinity of the center, the ingots 28A and 28B may be processed by feeding the ingot 28B toward the first and second lower cutting wire portions 261B and 262B. In this case, after the first and second wires 151 and 152 are wound around the guide roller set of the guide rollers 24A to 24H from the roller 11F shown in FIG. 1 until they leave the guide roller set toward the roller 11G. Since the time in which the ingots 28A and 28B are in close proximity to each other is shortened, the damage to the wires 151 and 152 is reduced in the electric discharge machining, and the cutting of the wires 151 and 152 during the electric discharge machining is suppressed. There is an effect.

Another embodiment of the present invention will be described with reference to FIGS. Parts similar to those of the embodiment described with reference to FIG. 1 to FIG. As shown in FIG. 8, in the present embodiment, the first, second, and third processing units 101, 102, and 103 are provided, and each processing unit 101, 102, and 103 has a rotary electrode 200A ₁ , respectively. 200A ₂ , 200A ₃ and a common idle roller 300A arranged so as to face each of the rotating electrodes 200A ₁ , 200A ₂ , 200A ₃ . Each processing unit 101, 102, 103 is described with reference to FIG. 1, and the delivery bobbin 10 </ b> A, the take-up bobbin 10 </ b> B, the pulleys 11 </ b> A to 11 </ b> I, the dancer roll 12, and the speed pulley 16 described with reference to FIG. , A first wire tension sensor 13A, a second wire tension sensor 13B, a torque motor 25D, a clamp unit 19, a clamp roller 19a, a tension pulley 18, a positioning motor 25G, and a wire alignment unit 21. Further, the wires 151, 152, 153 of the processing units 101, 102, 103 are wound around the common guide rollers 24A to 24H a plurality of times. In FIG. 8, these components are not shown. In the embodiment shown in FIG. 8, each wire 151, 152, 153 of each processing unit 101, 102, 103 is wound around each guide roller set three times, and each wire 151, 152, 153 has a three-row configuration. It has become.

As shown in FIGS. 8 and 9, the rotating electrodes 200 </ _b > A ₁ , 200 </ _b > A ₂ , 200 </ _b > A ₃ have cylindrical electrode members 201 </ _b > A ₁ , 201 </ _b > A ₂ , 201 </ _b > A ₃ fitted on the outer periphery of a common insulating shaft 275. The electrode members 201A ₁ , 201A ₂ , 201A ₃ are separated from each other and are electrically insulated. The insulating shaft 275 is rotatably attached to the base 250A by two ball bearings 276. Each electrode arm 270A ₁ , 270A ₂ , 270A ₃ is rotatably attached to a common insulating shaft 273 attached to the base 250A, and a roller shape is formed on the tip side of each electrode arm 270A ₁ , 270A ₂ , 270A ₃ . Connection electrodes 271A ₁ , 271A ₂ , and 271A ₃ are rotatably attached. Each electrode arm 270A ₁ , 270A ₂ , 270A ₃ is urged by a spring (not shown) so that the connection electrodes 271A ₁ , 271A ₂ , 271A ₃ at the tip are pressed against the electrode members 201A ₁ , 201A ₂ , 201A _3. ing. The electrode arms 270A ₁ , 270A ₂ , and 270A ₃ are connected to the rotary electrode connection lines 296B ₁ , 296B ₂ , and 296B ₃ of the first, second, and third machining power supply units 29R, 29C, and 29L (not shown). each machining power source unit 29R, 29C, discharge machining power each electrode arm 270A ₁ from 29L, 270A _2, 270A ₃ each connection from the electrode 271A _1, 271A _2, the electrode member 201A ₁ through 271A _3, 201A _2, It is supplied to the 201A _3. Each electrode member 201A ₁ , 201A ₂ , 201A ₃ and each connection electrode 271A ₁ , 271A ₂ , 271A ₃ are made of a material such as copper having high electrical conductivity.

As shown in FIG. 8, the common idle roller 300A is made of a highly wear-resistant and insulating material such as a fluorine-based material, a nylon-based material, or ceramics, and is rotatably attached around the rotating shaft 301A. . Further, a V-shaped groove around which the wires 151, 152, and 153 are wound is provided on the outer peripheral surface of the idle roller 300A as described with reference to FIG. Each wire 151, 152, 153 is sandwiched between each electrode member 201A ₁ , 201A ₂ , 201A ₃ and the outer peripheral surface of the idle roller 300A and pressed against each electrode member 201A ₁ , 201A ₂ , 201A ₃ The electric discharge machining power is supplied from the electrode members 201A ₁ , 201A ₂ , 201A ₃ to the wires 151, 152, 153.

Also in this embodiment, each of the rotating electrodes 200A ₁ , 200A ₂ , 200A ₃ can supply power to each of the wires 151, 152, 153 in a state where there is almost no relative speed to each of the wires 151, 152, 153. , 152, 153 and the electrode members 201A ₁ , 201A ₂ , 201A ₃ are not slipped, and the wear of the electrode members 201A ₁ , 201A ₂ , 201A ₃ can be suppressed, and the wires 151, 152, can instantaneously gap between because it sandwiched between a 153 and electrode member 201A _1, 201A _2, 201A ₃ and each wire 151, 152, 153 and the respective electrode members 201A _1, 201A _2, 201A ₃ each wire 151, 152, 153 and the respective electrode members 201A Te _1, 201A _2, discharge is issued with the 201A ₃ It is suppressed that can be performed stably for a long time processing.

Further, the wires 151, 152, 153 as described with reference to FIG. 4B or 4C are wound around the outer peripheral surfaces of the electrode members 201A ₁ , 201A ₂ , 201A ₃ . Character-shaped grooves 206A ₁ , 206A ₂ , 206A ₃ or semicircular grooves 207A ₁ , 207A ₂ , 207A ₃ may be provided.

Another embodiment of the present invention will be described with reference to FIG. Parts similar to those of the embodiment described with reference to FIGS. 1 to 9 are denoted by the same reference numerals, and description thereof is omitted. In the present embodiment, the upstream side and the downstream side in the feed direction of the first wire 151 of the rotating electrode 200C ₁ disposed on the center line 101C of the processing unit 101 are symmetrical with respect to the center line 101C. Idle rollers 301C ₁ and 301D ₁ are arranged. In the idle rollers 301C ₁ and 301D ₁ , the winding angle of the first wire 151 around the rotating electrode 201C ₁ is θ of the winding angle of the first wire 151 around the rotating electrodes 201A ₁ and 201B ₁ described in FIG. It is arranged so as to have the same angle as ₁ . Each idle roller 301C ₁ , 301D ₁ has a distance between the rotating electrode 201C ₁ and the first upper cutting wire portion 261A and the first wire 151 between the rotating electrode 201A ₁ and the first upper cutting wire portion 261A. equal distance along the feed direction, and the rotary electrode 201C ₁ and the first wire 151 between the first distance and the rotating electrode 201B ₁ of the lower cutting wire portion 261B first lower cutting wire portion 261B Are arranged such that the distances along the feed direction are equal. In the present embodiment, the two ingots 28A and 28B are fed toward the cutting wire portions 261A and 261B by the common work feeding unit 27. This embodiment also has the same effect as the embodiment described above with reference to FIGS. Further, in the present embodiment, since two ingots 28A and 28B are simultaneously fed by one work feeding unit 27, a simpler configuration can be achieved.

10A feed bobbin, 10B take-up bobbin, 11A to 11I pulley, 12 dancer roll, 13A, 13B wire tension sensor, 16 speed pulley, 17 guide, 18 tension pulley, 19 clamp unit, 19a clamp roller, 21 wire alignment unit, 22 Sliding clutch, 24A-24H guide roller, 25EA, 25EB feed motor, 25B speed motor, 25C draw motor, 25D torque motor, 25E stepping motor, 25F, 25G positioning motor, 25H take-up motor, 261A-264B cutting wire portion, 26CA ₁ , 26CB ₁ , 28CA, 28CB center, 27A, 27B Work feed unit, 28A, 28B ingot, 28D, 101C Center line, 28a Machining groove, 29 Power supply, 29L, 29R Machining power supply unit, 31 position sensor, 32 disconnection detection sensor, 70 powder, 80 control unit, 100 multi-wire electric discharge machining apparatus, 101-103 machining unit, 124A-124D, 203A-203C, 301A-301C rotating shaft, 151-153 wire, 200A ₁ ~200C ₂ rotating electrode, 201A ₁ ~201C ₂ electrode member, 202A ₁ ~202C ₂ conductive bearings, 203A, 273 and 275 insulating shaft, 204A conductive shaft, 205 a to 205 c rotation center, 206A ₁ ~207A ₂ grooves, 208A, 208A _1, 208A ₂ color, 208A ₃ end ring, 209 spacer, 210A stepped portion, 211A _1, 211A ₂ the inner ring, 212A _1, 212A ₂ the outer ring, 213A _1, 213A ₂ ball, 214A _1, 214A ₂ conductive Sex grease, 220A ₁ , 220A ₂ power supply terminal, 250A base, 270A _{1 to} 270A ₃ electrode arm, 271A _{1 to} 271A ₃ connection electrode, 276 ball bearing, 291a ₁ , 291a ₂ main switching transistor, 293a ₁ , 293a ₂ sub switching transistor, 292a ₁ , 292a ₂ main DC power supply, 294a ₁ , 294a ₂ sub DC power supply, 295, 295L, 295R plus side output line, 295A, 295B ingot connection line, 296A _{1 to} 296C ₂ rotating electrode connection line, 296L, 296R minus side output line 297 Electric discharge machining pulse, 298 Residual charge neutralization pulse, 299 High frequency pulse, 300A, 300A _{1 to} 300D ₁ idle roller.

Claims (11)

A guide roller set including a plurality of guide rollers arranged at intervals, and a plurality of guide roller sets wound around the guide roller set at intervals in the longitudinal direction of each guide roller, A plurality of cutting wire portions spaced apart from each other between a pair of adjacent guide rollers are arranged on both sides in the longitudinal direction of the wire of each set of cutting wire portions, touching each strip of the wire, A plurality of machining units including a plurality of rotating electrodes that rotate in the same direction as the feed direction and feed a common electric discharge machining power to each strip of the wire;
A machining power supply for supplying electric discharge machining power to each rotating electrode,
Each guide roller of each processing unit is coaxially disposed adjacent to each other in the direction of each rotation axis, and each guide roller of each adjacent processing unit is electrically insulated from each other,
Each rotating electrode of each processing unit is coaxially arranged adjacent to each other in the direction of each rotation axis, and each rotating electrode of each adjacent processing unit is electrically insulated from each other,
Each set of cutting wire portions of each processing unit is arranged side by side in the longitudinal direction of the wire,
Each rotating electrode has a first rotating electrode disposed on the upstream side in the wire feeding direction of the first cutting wire subset on the most upstream side in the wire feeding direction, and on the most downstream side in the wire feeding direction. A second rotating electrode disposed downstream of a certain second cutting wire portion set in the wire feeding direction, and a third rotating electrode provided in the middle of each set of cutting wire portions along the wire feeding direction; Including
A multi-wire electric discharge machining apparatus for machining each workpiece by discharging each cutting unit between each set of machining units and each workpiece while feeding each wire of each machining unit in the winding direction. The multi-wire electric discharge machining apparatus according to claim 1,
Each rotating electrode is a cylindrical conductor,
A multi-wire electric discharge machining apparatus. The multi-wire electric discharge machining apparatus according to claim 1 or 2,
Each rotating electrode is arranged one by one at an equidistant position in the opposite direction along the wire winding direction from the center of each set of cutting wire portions,
A multi-wire electric discharge machining apparatus. The multi-wire electric discharge machining apparatus according to any one of claims 1 to 3,
Each processing unit is arranged upstream or downstream in the wire feeding direction of each rotating electrode, or on both sides, or opposed to each rotating electrode, and includes a plurality of idle rollers that press each strip of the wire of each processing unit against each rotating electrode. Preparing,
A multi-wire electric discharge machining apparatus. The multi-wire electric discharge machining apparatus according to claim 4 ,
Each idle roller has each wire of each processing unit sandwiched between each rotating electrode,
A multi-wire electric discharge machining apparatus. The multi-wire electric discharge machining apparatus according to any one of claims 1 to 5 ,
Each conductive bearing to which each rotating electrode is attached outside the outer ring,
A shaft on which the inner ring of each conductive bearing is electrically insulated and mounted coaxially;
A power supply member electrically connected to each inner ring of each conductive bearing,
A multi-wire electric discharge machining apparatus. The multi-wire electric discharge machining apparatus according to any one of claims 1 to 5 ,
A rotating shaft to which each rotating electrode is insulated and attached;
Each connecting electrode being pressed against the outer surface of each rotating electrode and supplying electric discharge machining power to each rotating electrode,
A multi-wire electric discharge machining apparatus. The multi-wire electric discharge machining apparatus according to any one of claims 1 to 7 ,
The electric discharge machining power is a high frequency pulse including an electric discharge machining pulse and a residual charge neutralizing pulse following the electric discharge machining pulse at a voltage opposite to the electric discharge machining pulse,
A multi-wire electric discharge machining apparatus. The multi-wire electric discharge machine according to claim 8 ,
The machining power source generates at least one main switching transistor for generating an electric discharge machining pulse, at least one main DC power supply, and a residual charge discharging pulse having a voltage opposite to that of the electric discharge machining pulse in order to remove the residual electric charge after the electric discharge machining. Including a plurality of machining power supply units each including at least one sub-switching transistor and at least one sub-direct current power supply, each supplying electric discharge machining power to each machining unit;
A multi-wire electric discharge machining apparatus. A guide roller set including a plurality of guide rollers arranged at intervals, and a plurality of guide roller sets wound around the guide roller set at intervals in the longitudinal direction of each guide roller, A plurality of cutting wire portions spaced apart from each other between a pair of adjacent guide rollers are arranged on both sides in the longitudinal direction of the wire of each set of cutting wire portions, touching each strip of the wire, A plurality of rotating units that rotate in the same direction as the feed direction and feed a common electric discharge machining power to each strip of the wire, and a machining that supplies electric discharge machining power to each rotating electrode. A power supply, and each guide roller of each processing unit is coaxially disposed adjacent to each other in the direction of each rotation axis, and each guide roller of each adjacent processing unit is electrically connected to each other. Each rotating electrode of each processing unit is coaxially disposed adjacent to each other in the direction of each rotation axis, and each rotating electrode of each adjacent processing unit is electrically insulated from each other using a multi-wire electric discharge machining apparatus, Each set of cutting wire portions of each processing unit is arranged side by side in the longitudinal direction of the wire, and each rotating electrode is upstream of the first cutting wire portion set on the most upstream side in the wire feeding direction. A first rotating electrode disposed in the wire feed direction, a second rotating electrode disposed downstream in the wire feed direction of the second cutting wire subset located on the most downstream side in the wire feed direction, and in the wire feed direction And a third rotating electrode provided in the middle of each set of cutting wire portions, and each set of cutting wire portions and each carbonization case of each processing unit while feeding each wire of each processing unit in the winding direction. A method of producing a silicon carbide plate cutting a plurality of silicon carbide plates was discharged from an ingot of the silicon carbide between the ingot containing,
Generating a high-frequency pulse by turning on and off the switching transistor of the machining power supply and supplying this high-frequency pulse as electric power for electric discharge machining;
A method for producing a silicon carbide plate characterized by the above. It is a manufacturing method of the silicon carbide board according to claim 10,
Different positions in the direction crossing each set of cutting wire portions of each silicon carbide ingot;
A method for producing a silicon carbide plate characterized by the above.

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