JP6945489B2 - Multi-wire electric discharge machine - Google Patents

Description

The present invention relates to a multi-wire electric discharge machining apparatus that simultaneously performs electric discharge machining at a plurality of positions of an workpiece.

In the multi-wire electric discharge machining apparatus, a plurality of linear portions parallel to each other are formed by rotating one wire electrode a plurality of times, and electric discharge machining is performed at each linear portion at the same time, whereby a plurality of strips are processed. It is possible to cut out the plate-shaped body at once. The multi-wire electric discharge machining device removes the machining debris generated by electric discharge machining from the machining groove by injecting the machining fluid into the machining groove formed in the workpiece by electric discharge machining, and the wire whose temperature has become high due to the electric discharge. Cool the electrodes.

When the flow rate of the machining fluid that reaches the inside of the machining groove decreases, the machining chips tend to stay in the gap between the wire electrode and the machining position. The retention of work debris increases the frequency of discharge from the wire electrode to the work debris. When the frequency of discharge to the machining waste increases, the frequency of discharge to the machining position decreases, so that the machining efficiency of the multi-wire electric discharge machining apparatus decreases. Further, as the amount of accumulated processing waste increases, a short circuit between the wire electrode and the processing waste is likely to occur. A short-circuit current, which has a larger energy than the discharge current, flows between the wire electrode and the machining waste, so that the wire electrode is liable to be broken. Therefore, in the multi-wire electric discharge machining apparatus, in order to enable stable electric discharge machining, it is desirable that the machining debris can be discharged from the machining groove before the machining debris increases to the extent that a short circuit occurs. Is done.

Patent Document 1 discloses a technique of a multi-wire electric discharge machining apparatus having a nozzle capable of increasing the pressure of a machining fluid injected from a nozzle toward a machining groove. According to the technique of Patent Document 1, the discharge of machining waste is promoted by increasing the pressure of the machining fluid at the nozzle.

Japanese Patent No. 5172019

When the cut surface when the plate-shaped body is cut out from the work piece becomes large, a machining groove having a wide inner wall is formed, so that the flow velocity of the machining fluid tends to decrease due to friction between the inner wall of the machining groove and the machining fluid. Become. When the flow rate of the machining fluid decreases, the flow rate of the machining fluid inside the machining groove decreases, so that the machining waste discharged from the machining groove decreases. Even if the pressure of the machining fluid in the nozzle is increased by the technique of Patent Document 1, when the cut surface of the workpiece is large, the attenuation of the flow velocity of the machining fluid in the machining groove becomes large, so that the machining waste It may be difficult to promote emissions.

In the technique of Patent Document 1, the workpiece moves upward with respect to the nozzle as the processing progresses. When the workpiece has a cylindrical shape, the machining fluid is incident on the side surface of the cylinder of the workpiece, so that the distance between the incident position of the workpiece and the nozzle in the workpiece changes as the workpiece moves. .. When the machining fluid is incident on the center of the workpiece in the vertical direction, even if the nozzle is in close contact with the workpiece, as the incident position of the machining fluid moves away from the center of the workpiece in the vertical direction The side surface of the cylinder of the work piece moves away from the position of the nozzle, and the nozzle is not brought into close contact with the work piece. When the nozzle is in close contact with the workpiece, the machining fluid is easily press-fitted into the machining groove by the force of the machining fluid jetted from the nozzle. When the nozzle is not in close contact with the workpiece, the machining fluid is more easily flowed to the inside of the machining groove where friction with the inner wall occurs than inside the machining groove where friction is low, so that the nozzle is press-fitted into the machining groove. The flow rate of the processing liquid is reduced. For this reason, in the case of a cylindrical workpiece, when machining a position of the workpiece away from the center in the vertical direction, the flow rate of the machining fluid press-fitted into the machining groove is reduced, so that the machining is performed. The amount of work waste discharged from the groove is reduced. As described above, the technique described in Patent Document 1 has a problem that it may be difficult to promote the discharge of machining debris by reducing the amount of machining fluid that enters the inside of the machining groove. ..

The present invention has been made in view of the above, and an object of the present invention is to obtain a multi-wire electric discharge machining apparatus capable of promoting the discharge of machining chips generated by electric discharge machining.

In order to solve the above-mentioned problems and achieve the object, in the multi-wire discharge processing apparatus according to the present invention, the first bobbin from which the wire electrode is unwound and the wire electrode unwound from the first bobbin are wound up. A first guide roller and a second guide that guide the running of the wire electrode between the first bobbin and the second bobbin by winding the second bobbin and the wire electrode a plurality of times at intervals. It is equipped with a roller. The multi-wire electric discharge machine according to the present invention individually contacts a plurality of wire strips which are portions of the wire electrodes running in parallel with each other between the first guide roller and the second guide roller. Therefore, it is provided with a plurality of power supply electrons that apply a voltage between each of the plurality of wire portions and the workpiece. The multi-wire electric discharge machining apparatus according to the present invention is a relative operation of a wire electrode with respect to a work piece, and is a work formed on a work piece by electric discharge machining at each of a plurality of linear portions by applying a voltage. It is provided with a discharge operation control unit that controls a discharge operation that promotes discharge of machining chips from the groove. The multi-wire electric discharge machining apparatus according to the present invention includes a retention estimation unit that estimates the retention status of machining chips in each of the machining grooves formed in the workpiece. The discharge operation control unit controls the discharge operation based on the estimation result by the retention estimation unit.

According to the present invention, there is an effect that the discharge of machining waste generated by electric discharge machining can be promoted.

The figure which shows the structure of the multi-wire electric discharge machining apparatus which concerns on Embodiment 1 of this invention. A block diagram showing a machining control device included in the multi-wire electric discharge machining apparatus shown in FIG. 1 and a component of the multi-wire electric discharge machining apparatus controlled by the machining control device. The figure explaining the state which electric discharge machining is performed by the multi-wire electric discharge machining apparatus shown in FIG. The figure explaining the retention of the machining debris in electric discharge machining by the multi-wire electric discharge machining apparatus shown in FIG. The figure explaining the discharge operation by the multi-wire electric discharge machine shown in FIG. The first figure explaining the estimation of the retention state of work chips by the retention estimation unit of the multi-wire electric discharge machining apparatus shown in FIG. FIG. 2 is a second diagram for explaining the estimation of the retention state of machining chips by the retention estimation unit of the multi-wire electric discharge machining apparatus shown in FIG. The figure which shows the hardware configuration in the case where the function of the machining control device which the multi-wire electric discharge machining apparatus shown in FIG. 1 has is realized by the dedicated hardware. The figure which shows the hardware configuration in the case where the function of the machining control device which the multi-wire electric discharge machining apparatus shown in FIG. 1 has is realized by the processor which executes the program stored in the memory. The figure explaining the discharge operation by the multi-wire electric discharge machine which concerns on Embodiment 2 of this invention. The figure explaining the discharge operation by the multi-wire electric discharge machine which concerns on Embodiment 3 of this invention.

Hereinafter, the multi-wire electric discharge machine according to the embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited to this embodiment.

Embodiment 1.
FIG. 1 is a diagram showing a configuration of a multi-wire electric discharge machine 100 according to a first embodiment of the present invention. In the multi-wire electric discharge machining apparatus 100, a plurality of linear portions 2a parallel to each other are formed by orbiting one wire electrode 2 a plurality of times, and electric discharge machining is performed at each linear portion 2a at the same time. A plurality of plate-like bodies are cut out from the workpiece 10 at once. In the first embodiment, the workpiece 10 is, for example, a columnar ingot made of single crystal silicon.

In the multi-wire electric discharge machine 100, a first bobbin 1A to which the wire electrode 2 is fed and a wire electrode 2 unwound from the first bobbin 1A and circulated by a plurality of guide rollers 3, 4, 5, 6 are provided. It is provided with a second bobbin 1B to be wound up. The first bobbin 1A is capable of forward rotation in which the wire electrode 2 is fed out about the rotation axis and reverse rotation opposite to the forward rotation. The second bobbin 1B is capable of a forward rotation in which the wire electrode 2 is wound around a rotation axis and a reverse rotation opposite to the forward rotation. The first bobbin 1A is mounted on a traverse stage that reciprocates in the rotation axis direction. The second bobbin 1B is mounted on a traverse stage that reciprocates in the rotation axis direction. In FIG. 1, the traverse stage is not shown.

The plurality of guide rollers 3, 4, 5, and 6 are wound with the wire electrodes 2 a plurality of times at intervals to guide the running of the wire electrodes 2 between the first bobbin 1A and the second bobbin 1B. do. In the first embodiment, the multi-wire electric discharge machine 100 has four guide rollers 3, 4, 5, and 6. The number of guide rollers 3, 4, 5, and 6 provided in the multi-wire electric discharge machine 100 is not limited to four, and any number of guide rollers 3, 4, 5, and 6 may be provided.

A plurality of guide grooves at equal intervals are formed on the surfaces of the guide rollers 3, 4, 5, and 6. By winding the wire electrode 2 along the guide groove, the guide rollers 3, 4, 5, 6 are spaced apart from the wire electrodes 2 running in parallel between the guide rollers 3, 4, 5, 6. Is kept constant.

The wire electrode 2 unwound from the first bobbin 1A is wound in the order of the guide roller 3, the guide roller 4, the guide roller 5, and the guide roller 6, and the winding from the guide roller 3 is continued again. In this way, the wire electrode 2 is wound around the second bobbin 1B after making a plurality of turns between the guide rollers 3, 4, 5, and 6. The plurality of wire strips 2a are portions of the wire electrodes 2 that travel in parallel with each other between the guide roller 5 which is the first guide roller and the guide roller 6 which is the second guide roller. Is.

The multi-wire electric discharge machine 100 includes a stage 13 on which the workpiece 10 is placed. The stage 13 reciprocates in a vertical direction, which is a direction perpendicular to the traveling direction of the plurality of streaks 2a and the direction in which the plurality of streaks 2a are arranged in parallel. The stage 13 changes its position so that the workpiece 10 is relatively close to or separated from the plurality of streaks 2a by the reciprocating motion in the vertical direction. By electric discharge machining to the workpiece 10, the workpiece 10 is formed with machining grooves 11 along a plurality of strips 2a.

The vibration damping guide roller 7A is arranged between the workpiece 10 and the guide roller 6. The vibration damping guide roller 7B is arranged between the workpiece 10 and the guide roller 5. The vibration damping guide rollers 7A and 7B are provided with a plurality of guide grooves 8 at equal intervals. The vibration damping guide roller 7A and the vibration damping guide roller 7B keep the distance between the vibration damping guide rollers 7A and the vibration damping guide rollers 7B constant on both sides of the workpiece 10 in the traveling direction of the wire strips 2a.

The multi-wire electric discharge machine 100 includes a plurality of power supply electrons 12A and 12B for applying electrodes between each of the plurality of linear portions 2a and the workpiece 10. The power supply 12A is provided between the vibration damping guide roller 7A and the guide roller 6 corresponding to every other line portion 2a among the plurality of line portions 2a. The power supply 12B is provided between the vibration damping guide roller 7B and the guide roller 5 corresponding to the wire strips 2a other than the wire strips 2a corresponding to the power supply 12A among the plurality of wire strips 2a. ing. The power feeders 12A and 12B apply a voltage between each of the plurality of streaks 2a and the workpiece 10.

The processing power supply 14 is connected to the power supplies 12A and 12B and the workpiece 10. The processing power supply 14 outputs the current supplied to the power supplies 12A and 12B and the workpiece 10. The pulse oscillator 15 adjusts the pulse width of the voltage applied between the power supply electrons 12A and 12B and the workpiece 10, and starts and stops the pulse oscillation. The processing power supply unit 16 individually applies a pulse voltage to each of the power supply electrons 12A and 12B and the workpiece 10.

The nozzle 9A is arranged on the work piece 10 side with respect to the vibration damping guide roller 7A. The nozzle 9B is arranged on the workpiece 10 side of the vibration damping guide roller 7B. The plurality of streaks 2a are passed through the nozzle 9A and the nozzle 9B. The nozzles 9A and 9B have through holes through which a plurality of streaks 2a are passed. The machining fluid filled inside the nozzles 9A and 9B is ejected to the workpiece 10 through the through hole. In FIG. 1, the through holes of the nozzles 9A and 9B are not shown. When machining the workpiece 10, the nozzles 9A and 9B inject the machining fluid toward the machining groove 11 of the workpiece 10. The machining fluid pumped from the machining fluid tank is supplied to the nozzles 9A and 9B. The injection of the machining fluid from the nozzle 9A and the stop of the injection are switched by operating the flow rate adjusting valve provided between the pump and the nozzle 9A. The injection of the machining fluid from the nozzle 9B and the stop of the injection are switched by operating the flow rate adjusting valve provided between the pump and the nozzle 9B. In FIG. 1, the machining fluid tank, the pump, and the flow rate adjusting valve are not shown.

The rotation drive unit 17A has a motor that rotationally drives the first bobbin 1A. The traverse drive unit 18A drives a traverse stage that reciprocates the first bobbin 1A. The rotation drive unit 17B has a motor that rotationally drives the second bobbin 1B. The traverse drive unit 18B drives a traverse stage that reciprocates the second bobbin 1B. The traverse drive units 18A and 18B have a motor and a mechanism for converting the rotational motion of the motor into a linear motion. The stage drive unit 19 drives the stage 13. The stage drive unit 19 has a motor and a mechanism for converting the rotational motion of the motor into a linear motion. In FIG. 1, the motor and the mechanism are not shown.

The multi-wire electric discharge machine 100 includes a guide roller drive unit that rotationally drives the guide rollers 5 and 6, respectively, and a flow rate adjustment valve drive unit that switches the flow rate adjustment valve. In FIG. 1, the guide roller drive unit and the flow rate adjusting valve drive unit are not shown.

The machining control device 20 controls the entire multi-wire electric discharge machining device 100. The machining control device 20 controls the pulse oscillator 15, the rotary drive units 17A and 17B, the traverse drive units 18A and 18B, the stage drive unit 19, the guide roller drive unit, and the flow rate adjusting valve drive unit.

FIG. 2 is a block diagram showing a machining control device 20 included in the multi-wire electric discharge machining device 100 shown in FIG. 1 and a component of the multi-wire electric discharge machining device 100 controlled by the machining control device 20.

The machining control device 20 includes a wire control unit 21 which is a functional unit for controlling the rotation drive unit 17 and the traverse drive unit 18, a stage control unit 22 which is a functional unit for controlling the stage drive unit 19, and a flow rate adjusting valve drive. It has a flow rate control unit 23 which is a functional unit for controlling the unit 29, and an oscillation control unit 24 which is a functional unit for controlling the pulse oscillator 15. The rotation drive unit 17 shown in FIG. 2 represents the rotation drive unit 17A and the rotation drive unit 17B shown in FIG. The traverse drive unit 18 represents the traverse drive unit 18A and the traverse drive unit 18B shown in FIG.

The rotation drive unit 17 rotates the first bobbin 1A and the second bobbin 1B under the control of the wire control unit 21. The bobbin 1 shown in FIG. 2 represents the first bobbin 1A and the second bobbin 1B shown in FIG. The traverse drive unit 18 operates the traverse stage 28 under the control of the wire control unit 21. The traverse stage 28 represents a traverse stage that operates the first bobbin 1A and a traverse stage that operates the second bobbin 1B. The multi-wire electric discharge machine 100 runs the wire electrode 2 by the operation of the bobbin 1 and the traverse stage 28.

The stage drive unit 19 operates the stage 13 under the control of the stage control unit 22. The flow rate adjusting valve driving unit 29 operates the flow rate adjusting valve 27 according to the control by the flow rate controlling unit 23. The flow rate adjusting valve 27 represents a flow rate adjusting valve that switches between injection and injection stop of the machining fluid from the nozzle 9A, and a flow rate adjusting valve that switches between injection of the machining fluid from the nozzle 9B and injection stop. The pulse oscillator 15 adjusts the pulse width and starts and stops the pulse oscillation according to the control by the oscillation control unit 24. In addition, the machining control device 20 has a guide roller control unit which is a functional unit for controlling the guide roller drive unit. In FIG. 2, the guide roller control unit is not shown.

Further, the machining control device 20 includes a discharge operation control unit 25, which is a function unit that controls a discharge operation that is a relative operation of the wire electrode 2 with respect to the workpiece 10 and promotes discharge of machining chips from the machining groove 11. It also has a retention estimation unit 26, which is a functional unit for estimating the retention status of the machining waste generated by electric discharge machining in the processing groove 11. The current sensor 26a measures the current value of the current flowing between the linear portion 2a and the workpiece 10 for each of the plurality of linear portions 2a. The retention estimation unit 26 estimates the retention status of machining chips in each machining groove 11 based on the current value which is the measurement result by the current sensor 26a.

FIG. 3 is a diagram illustrating a state in which electric discharge machining is performed by the multi-wire electric discharge machining apparatus 100 shown in FIG. The flow rate adjusting valve 27A switches between injecting the machining fluid from the nozzle 9A and stopping the injection. The flow rate adjusting valve 27B switches between injecting the machining fluid from the nozzle 9B and stopping the injection. The wire electrode 2 shown in FIG. 3 is one of the plurality of streaks 2a shown in FIG. The workpiece 10 is fixed to the stage 13 in a state in which a part of the workpiece 10 vertically below is embedded in the stage 13.

FIG. 3 schematically shows the inside of the machined groove 11 while the work piece 10 is being cut from vertically above to vertically below. FIG. 3 shows a cross section of a portion of the workpiece 10 corresponding to the machining groove 11. Such a cross section is parallel to the inner wall of the machined groove 11. The machined groove 11 is a hatched portion of the workpiece 10, and the machined position 30 represents the deepest position of the machined groove 11. In the state shown in FIG. 3, electric discharge machining is performed at the machining position 30.

The nozzles 9A and 9B are arranged so as to face each other with the workpiece 10 sandwiched in the traveling direction D of the wire electrode 2. The nozzle 9B, which is the first nozzle, injects the machining fluid toward the first direction, which is the traveling direction D at the time of electric discharge machining, and causes the machining fluid to flow into the machining groove 11. The nozzle 9A, which is the second nozzle, injects the machining fluid in the second direction opposite to the traveling direction D, and causes the machining fluid to flow into the machining groove 11.

The nozzles 9A and 9B inject the machining fluids having the same flow rate from each other toward the workpiece 10. A part of the machining fluid jetted from the nozzle 9A and a part of the machining fluid jetted from the nozzle 9B enter the inside of the machining groove 11. Of the machining fluids ejected from the nozzles 9A and 9B, the portion other than a part that has entered the inside of the machining groove 11 flows along the outer peripheral surface of the workpiece 10.

The machining fluid jetted from the nozzle 9A and entered into the machining groove 11 and the machining fluid jetted from the nozzle 9B and entered into the machining groove 11 collide with each other near the center position in the traveling direction D of the workpiece 10. do. The machining fluids that collide with each other travel vertically upward along the inner wall of the machining groove 11 and are discharged to the outside of the workpiece 10.

Inside the machining groove 11, machining scrap 31 is generated by electric discharge machining. The machining waste 31 is gathered near the center position of the workpiece 10 in the traveling direction D along the flow of the machining fluid that has entered the machining groove 11. When the flow rate of the machining fluid inside the machining groove 11 is such that the machining waste 31 can be pushed upward, the machining waste 31 is discharged from the machining groove 11 to the outside of the workpiece 10 along with the flow of the machining fluid. NS. When the flow rate of the machining fluid inside the machining groove 11 is lower than the flow rate that can push the machining waste 31 upward, the machining waste 31 stays inside the machining groove 11.

FIG. 4 is a diagram illustrating the retention of machining chips 31 in electric discharge machining by the multi-wire electric discharge machining apparatus 100 shown in FIG. The larger the cut surface of the workpiece 10 due to electric discharge machining, the lower the flow velocity of the machining fluid due to the friction between the inner wall of the machining groove 11 and the machining fluid. As the flow velocity of the machining fluid decreases, the flow rate of the machining fluid that enters the vicinity of the center position of the workpiece 10 and is discharged to the outside of the workpiece 10 decreases, so that the amount of machining waste 31 that stays increases. .. In the case of the cylindrical workpiece 10, the larger the diameter of the cylinder, the more the accumulated work waste 31 is likely to be.

When the work waste 31 stays in the gap between the wire electrode 2 and the work position 30, the frequency of discharge from the wire electrode 2 to the work waste 31 increases. When the frequency of discharge to the work waste 31 increases, the frequency of discharge to the work position 30 decreases, so that the work efficiency decreases. Further, as the amount of work waste 31 that stays increases, a short circuit between the wire electrode 2 and the work waste 31 is likely to occur. A short-circuit current having a larger energy than the discharge current flows between the wire electrode 2 and the work piece 31, so that the wire electrode 2 is likely to be disconnected.

In the case of machining a cylindrical workpiece 10, when machining the center of the workpiece 10 in the vertical direction, the distance between the nozzle 9A and the outer peripheral surface of the workpiece 10 and the nozzle 9B and the workpiece 10 are processed. The distance between the work piece 10 and the outer peripheral surface is the shortest. The nozzles 9A and 9B are brought into close contact with the workpiece 10. When the nozzles 9A and 9B are brought into close contact with the workpiece 10, the machining fluid is easily press-fitted into the machining groove 11 by the force of the machining fluid jetted from the nozzles 9A and 9B. When the incident position of the machining fluid is separated from the center of the workpiece 10 in the vertical direction, the nozzles 9A and 9B are separated from the workpiece 10. When the nozzles 9A and 9B are not in close contact with the workpiece 10, the momentum of the machining fluid when the nozzles 9A and 9B are in close contact with the workpiece 10 may be weakened as compared with when the nozzles 9A and 9B are in close contact with the workpiece 10. be. The farther the nozzles 9A and 9B are from the workpiece 10, the easier it is for the machining fluid to flow to a direction other than the machining groove 11 where the friction is less than the inside of the machining groove 11 where friction with the inner wall occurs. The flow rate of the processing liquid press-fitted into the inside of 11 is reduced. Further, the flow rate of the machining fluid press-fitted into the machining groove 11 can be reduced by diffusing the machining fluid from the nozzles 9A and 9B until it reaches the workpiece 10. Therefore, in the case of the cylindrical workpiece 10, the flow rate of the machining fluid press-fitted into the machining groove 11 is reduced when machining a position of the workpiece 10 away from the center in the vertical direction. As a result, the processing waste discharged from the processing groove 11 may be reduced.

When the width of the machining groove 11 formed in the workpiece 10 by the multi-wire electric discharge machining apparatus 100 is narrower than the width of the machining fluid injected from the nozzles 9A and 9B, the machining fluid injected from the nozzles 9A and 9B A part of the workpiece hits the surface of the workpiece 10 without entering the machining groove 11. In the case of the cylindrical workpiece 10, when the incident position of the machining fluid is far from the center of the workpiece 10 in the vertical direction, the machining fluid is obliquely incident on the surface of the workpiece 10. Therefore, when the incident position of the machining fluid is far from the center of the workpiece 10 in the vertical direction, the workpiece 10 is compared with the case where the machining fluid is incident on the center of the workpiece 10 in the vertical direction. The working liquid that travels in a direction close to the surface direction of the above will be incident. When the machining fluid that travels in a direction close to the surface of the workpiece 10 is incident, the machining fluid that is incident on the surface of the workpiece 10 flows along the surface of the workpiece 10. In this way, in the case of a cylindrical workpiece, when machining a position of the workpiece 10 away from the center in the vertical direction, the surface of the workpiece 10 is affected by the machining fluid that did not enter the machining groove 11. The flow of the processing liquid is likely to occur.

FIG. 4 shows a state when the machining position 30 is a position above the center of the workpiece 10 in the vertical direction. In this case, the flow rate of the machining fluid press-fitted into the machining groove 11 is smaller than that when the machining position 30 coincides with the center of the workpiece 10 in the vertical direction. The work waste 31 tends to stay.

The machining fluid injected from the nozzles 9A and 9B flows along the outer peripheral surface of the workpiece 10 in addition to entering the inside of the machining groove 11. In the state shown in FIG. 4, after climbing along the outer peripheral surface of the workpiece 10, a flow of peeling upward from the outer peripheral surface occurs. As a result of the flow of peeling upward from the outer peripheral surface, a spiral flow as shown by the circular arrow in FIG. 4 is generated in the upper part of the processing groove 11. The spiral flow once flows upward from the machined groove 11, then changes its direction downward and returns to the inside of the machined groove 11 again. Since such a spiral flow is generated near the flow of the machining fluid discharged upward from the inside of the machining groove 11, the flow of the machining fluid discharged from the inside of the machining groove 11 to the outside of the machining groove 11 is hindered. .. Therefore, in a state where a vortex-like flow is generated, the machining waste 31 tends to stay inside the machining groove 11.

For example, when cutting a workpiece 10 which is a semiconductor crystal having a cylindrical shape having a diameter of 4 inches, a portion having a length H from the upper end of the workpiece 10 of about 10 mm to 15 mm is machined. It has been verified by the processing experiments of the inventors that the wire electrode 2 tends to be often broken during the process. Further, it was verified by the inventors' fluid simulation that the working liquid collides with the outer peripheral surface from an oblique direction with respect to the outer peripheral surface of the workpiece 10 to form a flow of the working liquid along the outer peripheral surface. Has been done. As described above, due to the shape of the workpiece 10, the retention of the machining waste 31 due to the decrease in the flow rate of the machining fluid flowing inside the machining groove 11 and the disconnection of the wire electrode 2 may easily occur. be.

FIG. 5 is a diagram illustrating a discharge operation by the multi-wire electric discharge machine 100 shown in FIG. Here, it is assumed that the multi-wire electric discharge machine 100 has started the discharge operation in the state (A) shown in FIG. The discharge operation is a relative operation of the wire electrode 2 with respect to the workpiece 10, and is an operation of promoting discharge of the work waste 31 from the work groove 11. In FIG. 5, the wire electrode 2 is one of a plurality of streaks 2a. In the first embodiment, the discharge operation is a reciprocating operation of the stage 13 in the vertical direction, which is a direction perpendicular to the traveling direction D of the plurality of streaks 2a and the direction in which the plurality of streaks 2a are arranged in parallel. The discharge operation control unit 25 controls such a reciprocating operation.

At the start of the discharge operation, the discharge operation control unit 25 instructs the oscillation control unit 24 to stop the pulse oscillation. The pulse oscillator 15 stops the pulse oscillation according to the control by the oscillation control unit 24. The discharge operation control unit 25 stops the application of the pulse voltage by the plurality of power supply electrons 12A and 12B in the discharge operation. As a result, the multi-wire electric discharge machine 100 stops the electric discharge machining during the discharge operation. The multi-wire electric discharge machine 100 keeps the wire electrode 2 running under the control of the wire control unit 21 during the discharge operation. The multi-wire electric discharge machine 100 continues to inject the machining fluid under the control of the flow rate control unit 23 during the discharge operation.

The discharge operation control unit 25 instructs the stage control unit 22 to reciprocate the stage 13. In the example shown in FIG. 5, the stage driving unit 19 moves the stage 13 vertically downward in the transition from the state (A) to the states (B) and (C). Due to the vertical downward movement of the stage 13, the wire electrode 2 relatively moves vertically upward from the processing position 30 inside the processing groove 11. Due to the movement of the wire electrode 2 in the machining groove 11, the machining waste 31 staying above the wire electrode 2 is scraped vertically upward from the inside of the machining groove 11 together with the machining fluid to the outside of the machining groove 11. It is discharged.

The stage drive unit 19 moves the stage 13 vertically upward in the transition from the state (C) to the states (B) and (A). By moving the stage 13 vertically upward, the wire electrode 2 is returned to the machining position 30. The discharge operation control unit 25 causes the stage 13 to perform such a reciprocating movement a predetermined number of times. By moving the wire electrode 2 up and down a plurality of times in the processing groove 11, the processing waste 31 is scraped out of the processing groove 11. Further, by stirring the processing liquid inside the processing groove 11, the accumulated processing waste 31 is diffused and easily discharged together with the processing liquid. The multi-wire electric discharge machining apparatus 100 can promote the discharge of the machining waste 31 from the machining groove 11 by such a discharge operation.

The multi-wire electric discharge machine 100 can suppress disconnection of the wire electrode 2 due to a short circuit by stopping the application of the pulse voltage in the discharge operation. Further, the multi-wire electric discharge machining apparatus 100 can reduce the generation of new machining chips 31 due to the secondary discharge in the discharge operation and reduce the damage to the cut surface due to the secondary discharge by stopping the application of the pulse voltage. .. The multi-wire electric discharge machine 100 can reduce power consumption by stopping the application of the pulse voltage in the discharge operation.

The vertical movement of the stage 13 is set to be before the wire electrode 2 reaches the upper end of the processing groove 11. When the wire electrode 2 is removed from the machined groove 11, it becomes difficult to reinsert the wire electrode 2 into the machined groove 11. Therefore, by preventing the wire electrode 2 from being removed from the machining groove 11, it is possible to avoid a situation in which the wire electrode 2 cannot be returned to the original machining position 30.

Next, the estimation of the retention state of the machining waste 31 in the machining groove 11 will be described. FIG. 6 is a first diagram for explaining the estimation of the retention state of the machining waste 31 by the retention estimation unit 26 included in the multi-wire electric discharge machining apparatus 100 shown in FIG. The upper part of FIG. 6 shows an example of a graph showing the transition of the measurement result of the discharge current each time a pulse voltage is applied to one of the plurality of line portions 2a. The vertical axis of the graph represents the current value, which is the observed value of the discharge current, and the horizontal axis represents time. The current value is measured by the current sensor 26a.

In FIG. 6, the first threshold value, Th1, is a threshold value used when determining whether or not a discharge has occurred between the linear portion 2a and the workpiece 10 each time a pulse voltage is applied. do. When the current value is Th1 or more, it is determined that an electric discharge has occurred between the linear portion 2a and the workpiece 10. When the current value is less than Th1, it is determined that the line portion 2a and the workpiece 10 are in an open state. The second threshold value, Th2, is a threshold value of the current value in determining whether or not a short circuit has occurred between the linear portion 2a and the workpiece 10. When the current value exceeds Th2, it is determined that a short circuit has occurred between the linear portion 2a and the workpiece 10. The graph shown in the upper part of FIG. 6 shows the peak P1 of the current value when a discharge occurs and the peak P2 of the current value when a short circuit occurs.

The retention estimation unit 26 converts the current value into the amount of electric charge by time integration of the current value. The lower part of FIG. 6 shows an example of calculating the amount of electric charge based on the observed value of the discharge current shown in the upper part of FIG. The vertical axis of the graph shown in the lower part of FIG. 6 represents the current value of the discharge current, and the horizontal axis represents time. When the observed value of the discharge current is Th1 or more and less than Th2, the retention estimation unit 26 replaces the current value at the time when the observed value is Th1 or more with I1 which is a constant value. When the observed value of the discharge current is Th1 or more, the retention estimation unit 26 replaces the current value at the time when the observed value is Th2 or more with I2 which is constant and larger than I1. The graph shown in the lower part of FIG. 6 shows the transition of the current value after such replacement. The current value changes stepwise between 0, I1, and I2. The amount of charge Q is represented by the area of the region surrounded by the graph shown in the lower part of FIG. 6 and the horizontal axis.

The current value of the peak P1 is replaced with I1 in the lower part of FIG. For the peak P1, the charge amount Q, which is the product of the time when the current value is I1 and I1, represents an approximate value of the charge amount in the discharge of the peak P1. The current value of the peak P2 that is Th1 or more and less than Th2 is replaced with I1 in the lower part of FIG. The current value of Th2 or higher in the peak P2 is replaced with I2 in the lower part of FIG. The transition of the current value of the peak P2 is replaced with the gradual transition between I1 and I2. For the peak P2, the charge amount Q, which is the product of the time when the current value is I1 and I1 and the product of the time when the current value is I2 and I2, is an approximate value of the charge amount in the discharge of the peak P2. Represents. In this way, the retention estimation unit 26 obtains an approximate value of the amount of charge between the discharge and the short circuit, thereby performing a simple conversion from the observed value of the discharge current to the amount of charge Q.

FIG. 7 is a second diagram for explaining the estimation of the retention state of the machining waste 31 by the retention estimation unit 26 included in the multi-wire electric discharge machining apparatus 100 shown in FIG. The retention estimation unit 26 calculates an integrated value of the amount of electric charge obtained by conversion from the current value per unit time. The vertical axis of the graph shown in FIG. 7 represents the integrated value of the amount of electric charge per unit time, and the horizontal axis represents time.

It is presumed that the higher the integrated value of the amount of electric charge per unit time, the more the machining debris 31 stays in the machining groove 11, so that more discharges or short circuits with a high discharge current level occur. The retention estimation unit 26 reaches the limit where the wire electrode 2 can be broken at T1, which is the time when the integrated value of the amount of electric charge per unit time reaches Th3, which is a preset third threshold value. It is estimated that the retention of 31 has been reached. The retention estimation unit 26 instructs the discharge operation control unit 25 to perform a discharge operation based on the estimation result. The discharge operation control unit 25 performs the above-mentioned discharge operation in response to an instruction from the retention estimation unit 26. As a result, the multi-wire electric discharge machining apparatus 100 can prevent the wire electrode 2 from being disconnected due to the retention of the machining waste 31. Further, the multi-wire electric discharge machining apparatus 100 can promote electric discharge between the wire electrode 2 and the workpiece 10 by removing the machining chips 31, and can suppress a decrease in machining efficiency. The multi-wire electric discharge machine 100 enables stable electric discharge machining by preventing disconnection of the wire electrode 2 and suppressing a decrease in machining efficiency.

The retention estimation unit 26 may estimate the retention status by calculating the integrated value of the amount of charge per unit time only for the discharge current having a level higher than Th2. The retention estimation unit 26 may count the number of times a short circuit has occurred per unit time, and may instruct the discharge operation control unit 25 to perform a discharge operation when the count value exceeds a threshold value. In these cases as well, the multi-wire electric discharge machine 100 enables stable electric discharge machining by preventing disconnection of the wire electrode 2 and suppressing a decrease in machining efficiency.

The electric discharge operation control unit 25 may execute the electric discharge operation based on the position of the workpiece 10 where the electric discharge machining is performed reaches a preset position. The above-mentioned processing experiment or fluid simulation identifies a position where the wire electrode 2 tends to be broken due to the retention of the processing waste 31. It is set in the machining program executed by the multi-wire electric discharge machining apparatus 100 that the discharge operation control unit 25 performs the discharge operation when the processing reaches the specified position. The multi-wire electric discharge machine 100 automatically executes the discharge operation by the discharge operation control unit 25 when the machining reaches a position in the workpiece 10 where the wire electrode 2 tends to be broken frequently. As a result, the multi-wire electric discharge machining apparatus 100 enables stable electric discharge machining by preventing disconnection of the wire electrode 2 and suppressing a decrease in machining efficiency.

The function of the machining control device 20 included in the multi-wire electric discharge machining device 100 is realized by a processing circuit. The processing circuit is dedicated hardware mounted on the processing control device 20 of the multi-wire electric discharge machining device 100. The processing circuit may be a processor that executes a program stored in the memory.

FIG. 8 is a diagram showing a hardware configuration when the function of the machining control device 20 included in the multi-wire electric discharge machining device 100 shown in FIG. 1 is realized by dedicated hardware. The processing circuit 51, which is dedicated hardware, is a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or any of these. It is a combination.

FIG. 9 is a diagram showing a hardware configuration when the function of the machining control device 20 included in the multi-wire electric discharge machining device 100 shown in FIG. 1 is realized by a processor that executes a program stored in a memory. The processor 53 and the memory 54 are connected to each other so as to be able to communicate with each other. The processor 53 is a CPU (Central Processing Unit), a processing unit, an arithmetic unit, a microprocessor, a microcomputer, or a DSP (Digital Signal Processor). The function of the processing control device 20 is realized by the processor 53 and software, firmware, or a combination of software and firmware. The software or firmware is described as a program and stored in the memory 54. The memory 54 is non-volatile or volatile such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EEPROM (Erasable Programmable Read Only Memory), EEPROM (registered trademark) (Electrically Erasable Programmable Read-Only Memory). It is a built-in memory such as a sex semiconductor memory.

A part of the function of the machining control device 20 may be realized by dedicated hardware, and the other part of the function of the machining control device 20 may be realized by software or firmware. As described above, the function of the processing control device 20 can be realized by hardware, software, firmware, or a combination thereof.

According to the first embodiment, the multi-wire electric discharge machining apparatus 100 controls the machining waste 31 from the machining groove 11 under the control of the discharge operation control unit 25 based on the estimation result of the retention state of the machining waste 31 in the machining groove 11. Performs an electric discharge operation that encourages electric discharge. As a result, the multi-wire electric discharge machining apparatus 100 has the effect of promoting the discharge of the machining waste 31 generated by the electric discharge machining.

The multi-wire electric discharge machine 100 may perform a discharge operation other than the reciprocating operation of the stage 13. A case where the multi-wire electric discharge machine 100 performs an electric discharge operation other than the reciprocating operation of the stage 13 will be described in the second and subsequent embodiments.

Embodiment 2.
FIG. 10 is a diagram illustrating a discharge operation by the multi-wire electric discharge machine 100 according to the second embodiment of the present invention. In the second embodiment, the discharge operation is an operation of running the wire electrode at a higher speed than in the case of electric discharge machining. In the second embodiment, the same parts as those in the first embodiment are designated by the same reference numerals, and operations different from those in the first embodiment will be mainly described.

The discharge operation control unit 25 instructs the wire control unit 21 to run the wire electrode 2 at a higher speed than in the case of electric discharge machining. The rotary drive unit 17 rotationally drives the bobbin 1 at a higher speed than during electric discharge machining under the control of the wire control unit 21. The traverse drive unit 18 reciprocates the traverse stage 28 at a higher speed in synchronization with the rotational drive of the bobbin 1 than during electric discharge machining under the control of the wire control unit 21. The discharge operation control unit 25 keeps the wire electrode 2 running at high speed for a predetermined time.

Due to the high-speed running of the wire electrode 2 in the machining groove 11, the machining waste 31 is scraped out from the inside of the machining groove 11 in the traveling direction D together with the machining liquid, and is discharged to the outside of the machining groove 11. Further, by stirring the processing liquid inside the processing groove 11, the accumulated processing waste 31 is diffused and easily discharged together with the processing liquid. The multi-wire electric discharge machining apparatus 100 can promote the discharge of the machining waste 31 from the machining groove 11 by such a discharge operation.

The discharge operation control unit 25 may control the wire electrode 2 to travel at high speed and increase the flow rate of the machining fluid in the traveling direction D. The discharge operation control unit 25 increases the flow rate of the machining fluid injected from the nozzle 9B in the discharge operation as compared with the case of electric discharge machining. The discharge operation control unit 25 instructs the flow rate control unit 23 to increase the flow rate of the machining fluid injected from the nozzle 9B. The flow rate adjusting valve driving unit 29 operates the flow rate adjusting valve 27B according to the control by the flow rate controlling unit 23 so that the flow rate of the machining fluid injected from the nozzle 9B increases as compared with the case of electric discharge machining. As a result, the multi-wire electric discharge machining apparatus 100 increases the flow rate of the machining fluid injected in the same direction as the traveling direction D in which the wire electrode 2 travels at high speed, thereby discharging the machining waste 31 in the traveling direction D. Can be prompted.

According to the second embodiment, the multi-wire electric discharge machine 100 executes an electric discharge operation in which the wire electrode 2 runs at a higher speed than in the electric discharge machining. Further, the multi-wire electric discharge machining apparatus 100 increases the flow rate of the machining fluid injected in the traveling direction of the wire electrode 2. Also in the second embodiment, the multi-wire electric discharge machining apparatus 100 has an effect that the discharge of the machining waste 31 generated by the electric discharge machining can be promoted.

Embodiment 3.
FIG. 11 is a diagram illustrating a discharge operation by the multi-wire electric discharge machine 100 according to the third embodiment of the present invention. In the third embodiment, the discharge operation is a reciprocating operation of the wire electrode 2 in the first direction which is the traveling direction of the wire electrode 2 at the time of electric discharge machining and the second direction opposite to the first direction. .. In the third embodiment, the same parts as those of the first and second embodiments are designated by the same reference numerals, and operations different from those of the first and second embodiments will be mainly described.

In the state (A) shown in FIG. 11, the discharge operation control unit 25 causes the wire control unit 21 to travel the wire electrode 2 in the first direction D1, which is the traveling direction of the wire electrode 2 during electric discharge machining. Instruct. The rotation drive unit 17 causes the bobbin 1 to perform forward rotation in which the wire electrode 2 travels in the first direction D1 under the control of the wire control unit 21. The traverse drive unit 18 moves the traverse stage 28 in a direction parallel to the rotation axis synchronized with the rotation drive of the bobbin 1 that causes the wire electrode 2 to travel in the first direction D1 under the control of the wire control unit 21. Let me.

In the state (B) shown in FIG. 11, the discharge operation control unit 25 causes the wire electrode 2 to travel in the second direction D2 opposite to the traveling direction of the wire electrode 2 during electric discharge machining. Instruct 21. The rotation drive unit 17 causes the bobbin 1 to perform reverse rotation for traveling the wire electrode 2 in the second direction D2 under the control of the wire control unit 21. The traverse drive unit 18 moves the traverse stage 28 in a direction parallel to the rotation axis synchronized with the rotation drive of the bobbin 1 that causes the wire electrode 2 to travel in the second direction D2 under the control of the wire control unit 21. Let me.

The discharge operation control unit 25 repeats the transition between the state (A) and the state (B) shown in FIG. 11 a predetermined number of times. By stirring the processing liquid inside the processing groove 11, the accumulated processing waste 31 is diffused and easily discharged together with the processing liquid. The multi-wire electric discharge machining apparatus 100 can promote the discharge of the machining waste 31 from the machining groove 11 by such a discharge operation.

The discharge operation control unit 25 increases the flow rate of the machining fluid jetted from the nozzle 9B in the first direction D1 and the machining fluid jetted from the nozzle 9A in the second direction D2 according to the traveling direction of the wire electrode 2. Control may be performed to alternately switch between the increase in the flow rate and the increase in the flow rate. In the discharge operation, the discharge operation control unit 25 increases the flow rate of the processing liquid injected from the nozzle 9B when the wire electrode 2 is driven in the first direction D1 as compared with the case of electric discharge machining. In the state (A) shown in FIG. 11, the discharge operation control unit 25 instructs the flow rate control unit 23 to increase the flow rate of the machining fluid from the nozzle 9B. The flow rate adjusting valve drive unit 29 adjusts the flow rate adjusting valve 27B so that the flow rate of the machining fluid injected from the nozzle 9B is larger than the flow rate of the machining fluid injected from the nozzle 9A according to the control by the flow rate control unit 23. Make it work. In this way, the nozzle 9B increases the flow rate of the injected machining fluid as compared with the case of electric discharge machining.

In the discharge operation, the discharge operation control unit 25 increases the flow rate of the processing liquid injected from the nozzle 9A when the wire electrode 2 is driven in the second direction D2 as compared with the case of electric discharge machining. In the state (B) shown in FIG. 11, the discharge operation control unit 25 instructs the flow rate control unit 23 to increase the flow rate of the machining fluid from the nozzle 9A. The flow rate adjusting valve drive unit 29 adjusts the flow rate adjusting valve 27A so that the flow rate of the machining fluid injected from the nozzle 9A is larger than the flow rate of the machining fluid injected from the nozzle 9B according to the control by the flow rate control unit 23. Make it work. In this way, the nozzle 9A increases the flow rate of the injected machining fluid as compared with the case of electric discharge machining.

In the multi-wire electric discharge machining apparatus 100, the flow rate of the machining fluid injected in the first direction D1 and the flow rate of the machining fluid jetted in the second direction D2 are increased according to the direction in which the wire electrode 2 is run. And are switched alternately. As a result, the multi-wire electric discharge machining apparatus 100 increases the flow rate of the machining fluid injected in the same direction as the wire electrode 2 travels, thereby discharging the machining waste 31 in the direction in which the wire electrode 2 travels. Can be prompted.

According to the third embodiment, the multi-wire electric discharge machine 100 reciprocates the wire electrode 2. Further, the multi-wire electric discharge machining apparatus 100 increases the flow rate of the machining fluid injected in the first direction D1 and the flow rate of the machining fluid jetted in the second direction D2 in accordance with the traveling direction of the wire electrode 2. Alternately switch between increase and increase. Also in the third embodiment, the multi-wire electric discharge machining apparatus 100 has an effect that the discharge of the machining waste 31 generated by the electric discharge machining can be promoted.

The configuration shown in the above-described embodiment shows an example of the content of the present invention, can be combined with another known technique, and is one of the configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

1 bobbin, 1A 1st bobbin, 1B 2nd bobbin, 2 wire electrodes, 2a streaks, 3, 4, 5, 6 guide rollers, 7A, 7B vibration damping guide rollers, 8 guide grooves, 9A, 9B nozzles 10, Machining work, 11 Machining groove, 12A, 12B power supply, 13 stage, 14 Machining power supply, 15 pulse oscillator, 16 Machining power supply unit, 17, 17A, 17B rotary drive unit, 18, 18A, 18B traverse drive unit , 19 stage drive unit, 20 machining control device, 21 wire control unit, 22 stage control unit, 23 flow control unit, 24 oscillation control unit, 25 discharge operation control unit, 26 retention estimation unit, 26a current sensor, 27, 27A, 27B flow control valve, 28 traverse stage, 29 flow control valve drive unit, 30 machining position, 31 machining scraps, 51 processing circuit, 53 processor, 54 memory, 100 multi-wire discharge machining device.

Claims (11)

The first bobbin from which the wire electrode is fed, and
A second bobbin around which the wire electrode unwound from the first bobbin is wound, and
The wire electrodes are wound a plurality of times at intervals to guide the running of the wire electrodes between the first bobbin and the second bobbin with the first guide roller and the second guide roller. ,
Of the wire electrodes, the plurality of streaks are individually contacted with a plurality of streaks which are portions running in parallel with each other between the first guide roller and the second guide roller, and the plurality of streaks are contacted individually. A plurality of power supply electrons that apply a voltage between each of the workpieces and the workpiece,
It is a relative operation of the wire electrode with respect to the work piece, and is a work piece from a work groove formed in the work piece by electric discharge machining at each of the plurality of streaks by applying the voltage. An electric discharge operation control unit that controls the electric discharge operation that promotes electric discharge,
A retention estimation unit that estimates the retention status of the machining chips in each of the machining grooves formed in the workpiece, and a retention estimation unit.
Equipped with a,
The discharge operation control unit, based on the estimation result of the residence estimating unit, multi-wire electrical discharge machining apparatus characterized that you control the discharge operation. The residence estimating unit according to claim 1, characterized in that based on the current value of the current flowing between each said workpiece of said plurality of linear portions, estimates the condition of residence of the processing refuse The multi-wire electric discharge machine described in 1. The first bobbin from which the wire electrode is fed, and
A second bobbin around which the wire electrode unwound from the first bobbin is wound, and
The wire electrodes are wound a plurality of times at intervals to guide the running of the wire electrodes between the first bobbin and the second bobbin with the first guide roller and the second guide roller. ,
Of the wire electrodes, the plurality of streaks are individually contacted with a plurality of streaks which are portions running in parallel with each other between the first guide roller and the second guide roller, and the plurality of streaks are contacted individually. A plurality of power supply electrons that apply a voltage between each of the workpieces and the workpiece,
It is a relative operation of the wire electrode with respect to the work piece, and is a work piece from a work groove formed in the work piece by electric discharge machining at each of the plurality of streaks by applying the voltage. An electric discharge operation control unit that controls the electric discharge operation that promotes electric discharge,
With
The discharge operation control unit, the workpiece the electrical discharge machining is performed in which position preset on the basis that has reached the position discharging operation to the execution characteristics and to luma Ruchiwaiya discharge of Machining equipment. A stage on which the work piece is placed is provided.
3 . The multi-wire electric discharge machine according to any one of them. The multi-wire electric discharge machining apparatus according to any one of claims 1 to 3 , wherein the electric discharge operation is an operation of traveling the wire electrode at a higher speed than that of the electric discharge machining. The discharge operation is a reciprocating operation of the wire electrode in a first direction which is a traveling direction of the wire electrode and a second direction opposite to the first direction at the time of the electric discharge machining. The multi-wire electric discharge machining apparatus according to any one of claims 1 to 3. A first nozzle that injects the machining fluid toward the first direction, which is the traveling direction of the wire electrode at the time of the electric discharge machining, and causes the machining fluid to flow into the machining groove.
A second nozzle that injects the machining fluid in the second direction opposite to the traveling direction and causes the machining fluid to flow into the machining groove.
With
The multi-wire electric discharge machining according to claim 5 , wherein the discharge operation control unit increases the flow rate of the machining fluid injected from the first nozzle in the discharge operation as compared with the case of the electric discharge machining. Device. Before SL by injecting first working fluid toward the direction, a first nozzle for flowing working fluid into the working groove,
By injecting pre Symbol machining fluid toward the second direction, and a second nozzle for flowing working fluid into the working groove,
With
In the discharge operation, the discharge operation control unit increases the flow rate of the machining fluid injected from the first nozzle when the wire electrode is driven in the first direction as compared with the case of the electric discharge machining. The sixth aspect of claim 6, wherein when the wire electrode is moved in the second direction, the flow rate of the machining fluid injected from the second nozzle is increased as compared with the case of the electric discharge machining. Multi-wire electric discharge machine. The multi-wire electric discharge machining apparatus according to any one of claims 1 to 8 , wherein the discharge operation control unit stops application of the voltage in the discharge operation. The first bobbin from which the wire electrode is fed, and
A second bobbin around which the wire electrode unwound from the first bobbin is wound, and
The wire electrodes are wound a plurality of times at intervals to guide the running of the wire electrodes between the first bobbin and the second bobbin with the first guide roller and the second guide roller. ,
Of the wire electrodes, the plurality of streaks are individually contacted with a plurality of streaks which are portions running in parallel with each other between the first guide roller and the second guide roller, and the plurality of streaks are contacted individually. A plurality of power supply electrons that apply a voltage between each of the workpieces and the workpiece,
It is a relative operation of the wire electrode with respect to the work piece, and is a work piece from a work groove formed in the work piece by electric discharge machining at each of the plurality of streaks by applying the voltage. An electric discharge operation control unit that controls the electric discharge operation that promotes electric discharge,
A first nozzle that injects the machining fluid toward the first direction, which is the traveling direction of the wire electrode at the time of the electric discharge machining, and causes the machining fluid to flow into the machining groove.
A second nozzle that injects the machining fluid in the second direction opposite to the traveling direction and causes the machining fluid to flow into the machining groove.
With
The discharge operation is an operation of running the wire electrode at a higher speed than in the electric discharge machining.
The discharge operation control unit is a multi-wire electric discharge machining apparatus characterized in that in the discharge operation, the flow rate of the machining fluid injected from the first nozzle is increased as compared with the case of the electric discharge machining. The first bobbin from which the wire electrode is fed, and
A second bobbin around which the wire electrode unwound from the first bobbin is wound, and
The wire electrodes are wound a plurality of times at intervals to guide the running of the wire electrodes between the first bobbin and the second bobbin with the first guide roller and the second guide roller. ,
Of the wire electrodes, the plurality of streaks are individually contacted with a plurality of streaks which are portions running in parallel with each other between the first guide roller and the second guide roller, and the plurality of streaks are contacted individually. A plurality of power supply electrons that apply a voltage between each of the workpieces and the workpiece,
It is a relative operation of the wire electrode with respect to the work piece, and is a work piece from a work groove formed in the work piece by electric discharge machining at each of the plurality of streaks by applying the voltage. An electric discharge operation control unit that controls the electric discharge operation that promotes electric discharge,
A first nozzle that injects the machining fluid toward the first direction, which is the traveling direction of the wire electrode at the time of the electric discharge machining, and causes the machining fluid to flow into the machining groove.
A second nozzle that injects the machining fluid in the second direction opposite to the traveling direction and causes the machining fluid to flow into the machining groove.
With
The discharging operation is a reciprocating operation of the wire electrode in the first direction and the second direction.
In the discharge operation, the discharge operation control unit increases the flow rate of the machining fluid injected from the first nozzle when the wire electrode is driven in the first direction as compared with the case of the electric discharge machining. A multi-wire electric discharge machining apparatus characterized in that when the wire electrode is run in the second direction, the flow rate of the machining fluid injected from the second nozzle is increased as compared with the case of the electric discharge machining.

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