JP6187966B2 - Electrolytic machining apparatus, electrolytic machining method, and tool electrode manufacturing method - Google Patents

Description

  The present invention relates to an electrolytic processing apparatus, an electrolytic processing method, and a tool electrode manufacturing method.

There is known an electrolytic processing apparatus that removes a workpiece by applying a potential difference while injecting an electrolytic solution between the conductive workpiece and the electrode.
[Prior art documents]
[Patent Literature]
[Patent Document 1] Japanese Patent Application Laid-Open No. 2007-069328

  Since the conventional electrolytic processing apparatus immerses the workpiece in the electrolytic solution over a wide range, a potential difference is generated in a region other than the region to be processed. Therefore, it was unsuitable from the viewpoint of processing accuracy for the additional processing for forming a specific shape by partially depositing metal ions of the electrolytic solution.

  The electrolytic processing apparatus according to the first aspect of the present invention includes a tool electrode provided with a first inner through-hole for discharging an electrolytic solution toward the tip and a second inner through-hole for sucking the electrolyte from the tip. Apply the voltage so that the potential of the tool electrode is higher with respect to the workpiece placed opposite to the tip, and control the circulation of the electrolyte and the voltage of the application to the surface of the workpiece. And a controller for depositing metal.

  The electrolytic machining method according to the second aspect of the present invention includes an approach step of bringing the tool electrode closer to the workpiece, the inside of the tool electrode, the tip of the tool electrode and the surface of the workpiece, and the inside of the tool electrode in this order. A circulation step of circulating the electrolytic solution; and a deposition step of applying a voltage to the workpiece so as to increase the potential of the tool electrode to deposit a metal on the surface of the workpiece.

  The method for manufacturing a tool electrode according to the third aspect of the present invention distributes the electrolyte by slitting a single central plate to form a slit and sandwiching and fixing the central plate between two clamping plates. An internal through hole forming step for forming the internal through hole.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

It is a conceptual diagram which shows notionally the electrolytic processing machine which concerns on this embodiment. It is sectional drawing of the workpiece which is a tool electrode with which an electrolytic processing machine is mounted | worn, and a workpiece. It is sectional drawing of a tool electrode and a workpiece | work which shows each step of an additional process. It is sectional drawing of a tool electrode and a workpiece | work which shows the step of a removal process. It is a figure which shows the relationship between distance between electrodes and suction pressure. It is a control flow figure of electrolytic processing. It is a conceptual diagram explaining the application to a three-dimensional process. It is an external appearance perspective view of another tool electrode. It is explanatory drawing explaining the manufacturing method of a tool electrode. It is an enlarged view of the front-end | tip part of a tool electrode. It is a conceptual diagram which shows other electrolytic processing machine notionally. It is a conceptual diagram which shows other electrolytic processing machine notionally. It is a figure which shows the example of an applied voltage.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 is a conceptual diagram conceptually showing an electrolytic processing apparatus 10 according to the present embodiment. The electrolytic processing apparatus 10 is an apparatus that is equipped with a tool electrode 100 and performs additional processing and removal processing on a workpiece 200 to be processed by electrolytic processing. The additional processing is processing for forming a convex shape by depositing metal ions in the electrolytic solution on the surface of the workpiece 200. The removal process is a process of forming a concave shape by dissolving the surface of the workpiece 200, which is a metal, into the electrolytic solution. The electrolytic processing apparatus 10 can select whether to perform additional processing or removal processing by reversing the polarity applied to the tool electrode 100 and the workpiece 200. As shown in the figure, the direction away from the workpiece 200 along the central axis of the tool electrode 100 is the z-axis plus direction. One direction orthogonal to the z axis is defined as the x axis, and the direction orthogonal to both the z axis and the x axis is defined as the y axis. In the following several figures, the coordinate axes are displayed so that the orientation of each figure can be understood with reference to the coordinate axes of FIG.

  The electrolytic processing apparatus 10 includes a stage 300 on which the workpiece 200 is placed, a holder 400 that holds the tool electrode 100 so as to be movable back and forth in the z-axis direction, a pump 500 that sucks the electrolytic solution 550, and the tool electrode 100 through the electrolytic solution. A power supply 600 for applying a voltage between the workpieces 200 and a control unit 700 for controlling the entire electrolytic processing apparatus 10 are mainly provided. The control unit 700 includes a CPU 710 and an operation panel 720. The CPU 710 executes processing control in accordance with the processing procedure, processing conditions, and the like input via the operation panel 720. The operation panel 720 is a display device including an input unit such as a touch panel, and accepts input from an operator and displays menu items, processing progress, and the like.

  The tool electrode 100 is a metal tool electrode including a supply port 120 for supplying the electrolytic solution 550 and a recovery port 130 for collecting the electrolytic solution 550, as will be described in detail later. The electrolytic solution 550 is discharged from the tip portion 110 which is an end surface facing the planned machining position 210 of the workpiece 200 toward the planned machining position 210 and is collected again from the distal end portion 110. The tool electrode 100 is replaceably mounted on the holder 400. Specifically, it is fixed to the holder 400 by a clamp.

  The holder 400 is pivotally supported by a support column 410 fixed along the z-axis direction, and moves up and down the support column 410 by a driving force of a drive unit 420 provided integrally with the holder 400. Therefore, the tool electrode 100 advances and retreats with respect to the workpiece 200 as the holder 400 moves up and down. In addition, the drive part 420 is comprised by the motor containing the gear mechanism which meshes | engages with the support | pillar 410, for example.

  The stage 300 is a mounting table on which the workpiece 200 is fixed by the chuck 310. The chuck 310 is movable in the xy plane direction, and a planned machining position 210 set on the surface of the workpiece 200 can be disposed immediately below the tip portion 110 of the tool electrode 100.

  The pump 500 is a suction pump that sucks the electrolytic solution 550 through a recovery tube 562 connected to the recovery port 130. The pump 500 has, for example, a gauge pressure with a maximum suction pressure of −53 kPa and a maximum suction amount of about 0.6 L / min. The performance of the pump is appropriately selected according to the processing conditions such as the properties of the workpiece, the tool electrode and the electrolyte, the processing speed, and the like. Further, the pump 500 includes a pressure gauge 510, and the pressure gauge 510 outputs a suction pressure of the electrolytic solution 550. During processing, the CPU 710 receives the output of the pressure gauge 510 and monitors the suction pressure of the electrolytic solution 550.

  The collected electrolytic solution 550 is sent to the filtering device 580 to filter impurities. The filtering device 580 includes a concentration adjusting device 581 that keeps the ion concentration of the electrolytic solution 550 constant. The concentration adjusting device 581 detects the ion concentration of the electrolytic solution 550 and outputs it to the CPU 710. When the CPU 710 periodically monitors the ion concentration and detects a decrease in the ion concentration, the CPU 710 puts the electrolyte stored in the concentration adjusting device 581 into the electrolytic solution 550. When an increase in ion concentration is detected, a solvent such as water stored in the concentration adjusting device 581 is introduced into the electrolytic solution 550. That is, the CPU 710 executes concentration adjustment control for recovering the ion concentration via the concentration adjusting device 581. The filtered electrolytic solution 550 with the ion concentration maintained is sent to the tank 520 through the reflux tube 563 connected to the filtering device 580 and stored therein.

  The tank 520 is a container that stores the electrolytic solution 550. One end of a supply tube 561 is connected to the tank 520, and the other end of the supply tube 561 is connected to the supply port 120. The supply tube 561 is connected to the tank 520 and the supply port 120 so as to be filled with the electrolytic solution 550 even when the electrolytic processing apparatus 10 is stopped.

  Thus, the circulation path of the electrolytic solution 550 is as follows: tank 520 → supply tube 561 → tool electrode 100 (supply port 120 → tip portion 110 → recovery port 130) → recovery tube 562 → pump 500 → filter device 580 → reflux tube 563. → established as (tank 520). Here, the pump 500 for circulating the electrolytic solution 550 is provided as a suction pump connected to the recovery port 130 of the tool electrode 100 as described above. In the present embodiment, the electrolytic solution 550 is pushed out to the supply port 120. The pump for delivery is not connected. The mechanism by which the electrolytic solution 550 circulates through the tip portion 110 of the tool electrode 100 will be described later with reference to other drawings. In the present embodiment, the collected electrolytic solution 550 is filtered and returned to the tank 520. However, if the tank 520 can store an amount of the electrolytic solution 550 necessary for processing, the electrolytic solution 550 is stored in the tank. The configuration of returning to 520 is not necessary.

  The power supply 600 generates a potential difference between the workpiece 200 connected via the workpiece connection line 610 and the tool electrode 100 connected via the tool connection line 620. The power supply 600 is controlled by the CPU 710. Specifically, the CPU 710 sets a potential difference to be generated, intermittently generates a potential difference, or reverses the applied polarity. As for the applied polarity, the CPU 710 selects either a positive potential polarity that increases the voltage applied to the tool electrode 100 relative to the workpiece 200 or a negative potential polarity that decreases the voltage applied to the tool electrode 100 relative to the workpiece 200. Set For example, in the case of positive potential polarity, a positive voltage is applied to the tool electrode 100 with the workpiece 200 as the ground potential. Alternatively, as described later, when a positive offset voltage is applied to the workpiece 200, a voltage higher than the offset voltage is applied to the tool electrode 100. The CPU 710 can execute various types of application control. For example, a constant current mode is executed in which the value of the pulse current during machining is constant. As an example, the pulse current has a high level current value of 15 A, a low level current value of 0 A, a pulse width of 5 msec, and a pulse period of 50 msec.

  When the positive potential polarity is set, additional machining is performed on the planned machining position 210, and when the negative potential polarity is set, removal machining is performed on the planned machining position 210. Which applied polarity is controlled can be confirmed by, for example, an LED indicator 601.

  The workpiece connection line 610 may be directly connected to the workpiece 200 or may be connected to the workpiece 200 via the chuck 310 or the like. Similarly, the tool connection line 620 may be directly connected to the tool electrode 100 or may be connected to the tool electrode 100 via the holder 400 or the like.

  FIG. 2 is a cross-sectional view of the tool electrode 100 mounted on the electrolytic processing apparatus 10 and the workpiece 200 to be processed. The tool electrode 100 according to the present embodiment has a double cylindrical structure, and its body is held by a holder 400.

  More specifically, the two cylinders of the outer cylinder 140 and the inner cylinder 150 are concentrically fitted with the z-axis direction as the central axis. The inner diameter of the upper part of the outer cylinder 140 and the outer diameter of the upper part of the inner cylinder 150 are substantially equal and are fitted to each other. The outer cylinder 140 is formed to have a larger inner diameter than the upper part up to the tip part 110 except for the upper part. An O-ring 160 is fitted in a boundary portion on the lower end side of the upper part, and the outer cylinder 140 and the inner cylinder 150 are fixed to each other.

  For example, the outer diameter of the outer cylinder 140 is 10 mm, and the inner diameter other than the upper part is 8 mm. Similarly, the outer diameter of the inner cylinder 150 is 5 mm, and the inner diameter is 3 mm. In the figure, the ratio is different from this ratio from the viewpoint of explanation.

  By adopting the double cylindrical structure in this way, the first inner through hole 121 that is a space between the inner surface of the outer cylinder 140 and the outer surface of the inner cylinder 150, and the space on the central axis side from the inner surface of the inner cylinder 150. The second inner through hole 131 is formed. The first inner through hole 121 communicates with the supply port 120 through which the electrolytic solution 550 is introduced above the tool electrode 100. The second inner hole 131 communicates with the recovery port 130 that discharges the electrolytic solution 550 at the upper end of the tool electrode 100.

  The first inner through hole 121 is opened on the distal end 110 side, and the opening functions as a discharge port 171 that discharges the electrolytic solution 550 to the planned processing position 210. The second inner through-hole 131 is also opened on the distal end portion 110 side, and the opening functions as a suction port 172 that sucks the electrolyte solution 550. In such a structure, the discharge port 171 of the first inner through hole 121 is provided on the peripheral side at the distal end portion 110 than the suction port 172 of the second inner through hole 131.

  As shown in the drawing, the distal end portion 110 includes an outer cylinder distal end portion 141 that is a distal end portion of the outer cylinder 140 and an inner cylinder distal end portion 151 that is a distal end portion of the inner cylinder 150. The outer cylinder tip 141 has a taper that tapers so that the inner diameter gradually increases toward the tip. The inner cylinder front end 151 is formed as a flange extending in the direction of the outer cylinder 140. The collar portion is a flat surface on the surface of the workpiece 200 that faces the planned machining position 210, but has a taper that gradually becomes thinner toward the outer cylinder 140. In this embodiment, the outer diameter of the collar is 9 mm. Due to the taper of the outer cylinder tip 141 and the taper of the inner cylinder tip 151, the discharge port 171 becomes an opening narrower than the flow path cross section of the first inner through hole 121, and has a slightly peripheral edge in the vertical direction. Inclined in the direction.

  By forming the inner cylinder front end portion 151 as such a wide flange portion, the inner cylinder front end portion 151 functions as an effective electrode for flowing a current between the planned processing position 210. Therefore, if at least the inner cylinder 150 is a conductor, additional processing and removal processing can be performed even if the outer cylinder 140 is an insulator. Various conductors can be adopted for the inner cylinder 150 according to the material of the workpiece 200. For example, when the workpiece 200 is stainless steel, brass can be used. In particular, the surface may be plated with gold, silver or the like so that the tool electrode 100 itself does not melt when performing additional processing.

  In the present embodiment, the workpiece 200 is a nickel alloy, and the outer cylinder 140 and the inner cylinder 150 are both assumed to be brass whose surface is gold-plated. Further, the electrolytic solution 550 is appropriately selected according to the material of the tool electrode 100 and the workpiece 200. In this embodiment, an aqueous copper nitrate solution is used.

The outer cylinder tip 141 protrudes toward the workpiece 200 with respect to the inner cylinder tip 151. In the electrolytic machining, the tool electrode 100 and the workpiece 200 are not brought into contact with each other. At the time of processing, let c be the clearance of the outer cylinder tip 141 with respect to the surface of the workpiece 200. Further, the distance between electrodes is the distance between the inner cylindrical tip 151 and the surface of the workpiece 200 and g _w. Then, the projecting amount against the inner cylindrical tip 151 of the barrel tip portion _141, a _g w -c. In the present embodiment, the protruding amount is 50 μm.

  In such a cross-sectional structure, a flow path in a state where the tip portion 110 is sufficiently close to the surface of the workpiece 200 and the electrolytic solution 550 is sucked and circulated by the pump 500 will be described.

  The electrolytic solution 550 is introduced from the supply port 120 to the first inner through hole 121, passes through the first inner through hole 121, and reaches the discharge port 171. Then, the electrolytic solution 550 is discharged from the discharge port 171 by the suction force of the pump 500. Since the suction pressure acts from the suction port 172 side which is the central axis direction, and the outer cylinder tip 141 protrudes toward the surface side of the workpiece 200 and hardly leaks to the outside, almost the entire amount of the electrolyte 550 is It flows toward the suction port 172. That is, the electrolytic solution 550 moves to the suction port 172 so as to fill an inter-electrode space formed between the inner cylinder front end portion 151 and the surface of the workpiece 200. The electrolytic solution 550 taken into the tool electrode 100 again from the suction port 172 passes through the second inner through hole 131, reaches the recovery port 130, and is discharged to the outside.

  Further, the mechanism by which the electrolytic solution 550 circulates through the tip 110 of the tool electrode 100 will be described in detail with reference to FIG. FIG. 3 is a cross-sectional view of the tool electrode 100 and the workpiece 200 showing each stage of the additional machining.

  FIG. 3A is a diagram illustrating a state in which the tip portion 110 of the tool electrode 100 is gradually approaching the surface of the workpiece 200. At this stage, since the tip portion 110 is largely separated from the surface of the workpiece 200, only the air is taken in from the suction port 172 even if the pump 500 sucks, and therefore the electrolyte 550 is contained in the second inner portion. It is not led to the through hole 131. On the other hand, the first inner through hole 121 connected to the tank 520 is filled with the electrolytic solution 550. Here, as described above, the discharge port 171 is narrower than the cross section of the flow path of the first internal hole 121, and the supply port 120 is not connected to a pump for delivery. The surface tension at 171 stays in the first inner through hole 121 and does not drop from the discharge port 171. In the present embodiment, the electrolytic solution 550 is retained in the first inner through hole by surface tension, but the configuration in which the electrolytic solution 550 does not drop is not limited thereto. For example, a valve that opens and closes due to a pressure difference can be provided near the discharge port 171 to prevent dripping. Further, by adjusting the height of the supply port 120 and the height of the liquid level of the tank 520, dripping can be prevented by the pressure difference of the discharge port 171.

  FIG. 3B is a diagram illustrating a state in which the tip portion 110 of the tool electrode 100 has sufficiently approached the surface of the workpiece 200 and the electrolytic solution 550 has started to circulate. This is substantially the same as the state of the tip portion of FIG. When the tip 110 is gradually brought closer to the surface of the workpiece 200, the cross-sectional area of the flow path, which is the space between the inner cylinder tip 151 and the surface of the workpiece 200, is narrowed and taken in from the suction port 172. The air flow rate increases. Then, the pressure in the interelectrode space decreases due to the Benchery effect. When the pressure difference between the inter-electrode space and the first inner through hole 121 exceeds the threshold value, the electrolyte solution 550 that has remained in the first inner through hole until then blows out from the discharge port 171 and fills the inter-electrode space, and the suction port 172. It flows toward. Then, it is sucked up from the suction port 172 by the suction pressure and goes back through the second inner hole 131. In this way, circulation of the electrolytic solution 550 is started. If the distance between the tip portion 110 and the surface of the workpiece 200 is less than a certain distance, the circulation is continued.

Since the discharge port 171 is provided on the peripheral side of the suction port 172, the electrolytic solution 550 flows toward the central axis of the tool electrode 100. Therefore, it is possible to significantly reduce the leakage of the electrolyte solution 550 to the outside of the tip portion 110 rather than flowing toward the peripheral direction. That is, the electrolytic solution 550 can be circulated only in the processing region. Moreover, than the flow path cross-sectional g _w of interpolar space, since the small clearance c of the outer tube distal end portion 141 to the surface of the workpiece 200, while preventing leakage of the electrolytic solution 550, circulation of the electrolyte 550 It is also possible to reduce the inflow of air.

FIG. 3C shows a state where the copper in the electrolytic solution 550 is deposited and the convex shape grows. When energization by the power source 600 is started after the circulation of the electrolytic solution 550 is started, the electrolytic reaction proceeds and a bulge (convex shape) corresponding to the shape of the tip 110 is gradually formed. Since bumps are the inter-electrode distance g _w narrows growth, stepwise pulling the tool electrode 100 in accordance with the growth of the ridge direction of the arrow (z-axis positive direction).

  In the present embodiment, a delivery pump is not connected to the supply port 120, but a delivery pump that operates in cooperation with the pump 500 may be interposed in the supply tube 561. As described above, the Benchery effect occurs when the pressure difference between the interpolar space and the first inner hole 121 exceeds a threshold value. However, the delivery pump is actuated to temporarily turn the pressure in the first inner hole 121 temporarily. By increasing the efficiency, the blowing out of the electrolyte 550 can be promoted. By adopting such a configuration, the venturi effect can be effectively produced even for an electrolytic solution having a high viscosity, an electrolytic solution in which particulate matter is mixed, and the like.

  In the present embodiment, since the electrolytic solution 550 can be supplied in a limited manner to a target processing region, the processing proceeds so that the tip shape of the tool electrode 100 is transferred as a raised shape as illustrated. That is, highly accurate additional processing can be realized without processing progressing outside the target processing region.

  Here, the difference with the processing method by the conventional electrolytic processing apparatus is demonstrated. In a conventional electrolytic processing apparatus, at least a tool electrode tip is immersed in an electrolytic solution to approach a workpiece immersed in an electrolytic solution that fills an electrolytic bath, and a current is generated between the workpiece and the tool electrode. It was flowing. When such a configuration is adopted, a current path is also generated in the electrolyte solution between the tool electrode and a region other than the workpiece target region (the region facing the tip of the tool electrode). Machining has progressed in areas other than the machining target area. That is, the presence of the electrolytic solution outside the processing region causes a drift current to be generated, leading to a decrease in processing accuracy. In addition, in such a configuration, a large electrolytic bath is required, which consumes a large amount of electrolytic solution and is not preferable from the viewpoint of environmental pollution.

  In addition, according to another conventional electrolytic processing apparatus, the generated solution is removed by directly injecting the electrolytic solution onto the workpiece, thereby improving the processing speed. However, since the electrolytic solution is not supplied only to the target processing region, the processing accuracy is only slightly improved, and a large amount of electrolytic solution is still consumed. In order to realize highly accurate additional processing, it is important that the electrolytic solution is distributed only in the target processing region, in other words, the region other than the target processing region is not immersed in the electrolytic solution. From this point of view, the electrolytic processing machine is required to discharge the electrolytic solution to the target processing area and to reliably recover the liquid without leaking from the target processing area. The electrolytic processing apparatus 10 according to the present embodiment has an advantage that the processing accuracy is excellent by satisfying these requirements, and processing can be performed with a small amount of electrolytic solution.

FIG. 4 is a cross-sectional view of the tool electrode 100 and the workpiece 200, showing the stage of removal processing. In particular, a state in which drilling has been performed up to a machining depth f in hole machining which is one form of removal machining is shown. As shown in the drawing, the processing proceeds so that the tip shape of the tool electrode 100 is transferred as a hole shape. Since the hole is the distance between the electrodes g _w spreading growth, and sends the stepwise tool electrode 100 in the arrow direction (z-axis minus direction) in accordance with the growth of the hole. In the present embodiment, high-precision removal processing can be realized without progressing processing outside the target processing region. In other words, the side gap g _s that is the distance between the side surface of the tool electrode 100 and the inner surface of the hole formed by processing can be reduced.

  Next, the relationship between the distance between the electrodes and the suction pressure will be described. FIG. 5 is a diagram illustrating the relationship between the distance between the electrodes and the suction pressure with respect to the surface of the workpiece 200 at the start of electrolytic machining. In the figure, the horizontal axis represents the distance (μm) between the inner cylinder tip 151 and the surface of the workpiece 200, and the vertical axis represents the suction pressure (kPa) indicated by the pressure gauge 510.

From this experimental result, it can be seen that the distance between the electrodes can be estimated by monitoring the suction pressure. In particular, it can be seen that, in the additional processing, the suction pressure gradually decreases because the distance between the electrodes decreases as the bulge grows. Similarly, in the removal process, it can be seen that the suction pressure gradually increases because the distance between the electrodes increases as the hole grows. Therefore, in this embodiment, in the additional machining, the electrolytic machining apparatus 10 repeats the operation of pulling the tool electrode 100 apart by a certain amount when the suction pressure of the pressure gauge 510 monitored by the CPU 710 falls below _a predetermined threshold Pa. Then, a convex shape with a target height is formed. Similarly, in the removal process, by repeating a predetermined amount close operation of the tool electrode 100 Once above the threshold P _i the suction pressure of the pressure gauge 510 which CPU710 is monitored predetermined shaping the target depth of the concave shape .

Threshold _{P a} and the threshold _{P i} may appropriately set. The values may be different from each other or the same value. For example, in the example shown in the figure, both threshold values are set to −9 kPa corresponding to a boundary value of about 100 μm, which is a boundary value between a large area and a small area, in which the amount of change in the suction pressure with respect to the change in the distance between the poles. Further, the step amount for separating the tool electrode 100 in the additional processing and the step amount for bringing the tool electrode 100 close in the removal processing are preferably smaller than 100 μm adopted as the boundary value. 10 μm.

  In the conventional electrolytic processing apparatus, it is difficult to measure the distance between the electrodes. In many cases, the feed amount of the tool electrode per unit time is determined based on an empirical rule. However, since the feed control is not based on the actual distance between the poles, the processing speed is uneven or the processing shape is not stable. However, as in this embodiment, the control for monitoring the suction pressure correlated with the distance between the electrodes and moving the tool electrode is so-called feedback control, and according to such control, the optimum machining speed and A stable processed shape can be obtained. Even in the case where the delivery pump is supplementarily provided as in the above-described application example, if the delivery pump is stopped at the stage of monitoring the suction pressure, the feedback control can be executed similarly. .

  Next, control of the CPU 710 will be described. FIG. 6 is a control flow diagram of electrolytic processing. The flow starts when the tool electrode 100 is mounted on the holder 400 and the electrolytic processing apparatus 10 is activated.

  In step S101, the CPU 710 starts the pump 500 and starts suction. At this time, it is a stage of Fig.3 (a) and air is inhaled through the 2nd internal through-hole 131. FIG.

  In step S102, the CPU 710 drives the drive unit 420 to gradually bring the tool electrode 100 closer to the workpiece 200. In step S103, the CPU 710 receives the output value of the pressure gauge 510 and determines whether or not the circulation of the electrolyte 550 is started by determining whether or not the output value is included in the pressure range at the time of circulation of the electrolyte 550. Judge whether or not. The mechanism by which the electrolytic solution 550 starts to circulate when the tip 110 of the tool electrode 100 approaches the planned machining position 210 of the workpiece 200 is as described with reference to FIG. If it is determined that the circulation of the electrolytic solution 550 has not yet started, the process returns to step S102.

  If it is determined that the circulation of the electrolytic solution 550 has started, the CPU 710 proceeds to step S104, and determines whether the designated process is an additional process or a removal process. If it is determined that it is an additional process, the process proceeds to step S105. If it is determined that the process is a removal process, the process proceeds to step S112.

  When it is determined that the machining is additional processing and the process proceeds to step S <b> 105, the CPU 710 sets a positive potential polarity for increasing the voltage applied to the tool electrode 100 to the workpiece 200 and starts energizing the power source 600. In the workpiece 200, the electrolytic reaction starts from this point and the generation of the convex shape proceeds.

CPU710, by continuously receive the output value _{P t} of the pressure gauge 510 monitors the suction pressure in the additional processing. In step S106, CPU 710 determines whether or not lower than the (-9KPa in the example described with reference to FIG. 4) threshold _{P a} to the output value _{P t} as the suction pressure is determined in advance. If it is determined that it is not lower, step S106 is periodically repeated.

If the CPU 710 determines that it has fallen below, in step S107, the CPU 710 integrates the amount of the tool electrode 100 that has been pulled so far, and determines whether or not the convex shape has reached the target height. If it is determined that the target height has not been reached, the process proceeds to step S108, and the tool electrode 100 is pulled away by a predetermined distance D _a (10 μm in the example described with reference to FIG. 4). Then, the process returns to step S106. By repeating step S106 to step S108, the convex shape is increased. As described above, the CPU 710 and the drive unit 420 function as an adjustment unit that adjusts the distance between the tool electrode 100 and the workpiece 200.

  If it is determined in step S107 that the target height has been reached, the process proceeds to step S109, and the CPU 710 stops energization by the power source 600. Then, the process proceeds to step S110, and the drive unit 420 is driven to retract the tool electrode 100 from the workpiece 200. Then, since the circulation of the electrolytic solution 550 is automatically stopped in the retreat process, the suction of the pump 500 is stopped in step S111, and the series of additional processing is finished.

  When it is determined in step S104 that the machining is removal, and the process proceeds to step S112, the CPU 710 sets a negative potential polarity that lowers the voltage applied to the tool electrode 100 to the workpiece 200 and starts energizing the power supply 600. Let In the workpiece 200, the electrolytic reaction starts from this point and the generation of the concave shape proceeds.

CPU710, by continuously receive the output value _{P t} of the pressure gauge 510 monitors the suction pressure in the removal process. In step S113, CPU 710 has determined not to exceed. Determines whether exceeds -9kPa in the example described with reference to threshold P _{i (Fig.} 4 in which the output value P _t as the suction pressure is predetermined In that case, step S113 is periodically repeated.

If it is determined that it has been exceeded, in step S114, the CPU 710 integrates the feed amount of the tool electrode 100 up to that point (the amount approached), and determines whether or not the target depth has been reached. If it is determined that the target depth has not been reached, the process proceeds to step S115, and the tool electrode 100 is brought closer by a predetermined distance D _i (10 μm in the example described with reference to FIG. 4). Then, the process returns to step S113. By repeating step S113 to step S115, the concave shape is deepened.

  If it is determined in step S114 that the target depth has been reached, the process proceeds to step S116, and the CPU 710 stops energization by the power source 600. Then, the process proceeds to step S110, and the drive unit 420 is driven to retract the tool electrode 100 from the workpiece 200. Then, since the circulation of the electrolytic solution 550 is automatically stopped in the retreat process, the suction of the pump 500 is stopped in step S111, and the series of removal processes is completed.

  In the above description, the addition processing and the removal processing for moving the tool electrode 100 in the z-axis direction have been described. However, the workpiece 200 can also be subjected to three-dimensional processing by moving the tool electrode 100 also in the xy plane direction. . FIG. 7 is a conceptual diagram illustrating application to three-dimensional processing.

As shown in FIG. 7A, a removal process for forming an N-shaped recess on the surface of the workpiece 220 will be described. The electrolytic processing apparatus includes a drive unit that moves the tool electrode 100 in the xy plane direction, and sweeps the tool electrode 100 several times along the N shape according to the target depth. At this time, as shown in FIG. 7 (b), the machining depth s to proceed in a single sweep, keep smaller than inter-electrode distance g _w. If s <g _w , the tool electrode 100 can be moved in the direction of the arrow, so that the depth can be gradually increased by repeating the sweep, and the N-shaped concave portion of the target depth is formed on the workpiece. 220 can be formed on the surface. Instead of moving the tool electrode 100 in the xy plane direction with respect to the workpiece 220, the workpiece 220 may be moved in the xy plane direction with respect to the tool electrode 100.

  The same applies to the additional processing. For example, when forming an N-shaped convex part on the surface of the workpiece 220, the applied polarity is reversed, and the tool electrode 100 is swept several times along the N-shape according to the target height. good. Of course, additional processing and removal processing may be performed continuously. If the relative movement of the tool electrode 100 and the workpiece 220 and the applied polarity are controlled, addition and removal can be arbitrarily performed, so that a three-dimensional shape can be formed more freely. If the user programs the control unit 700 in advance via the operation panel 720, for example, the CPU 710 can continuously form a three-dimensional shape while switching between additional processing and removal processing according to the program. With such a configuration, the electrolytic processing apparatus according to the present embodiment enables modeling like a 3D printer using a metal as a material.

  In addition, according to the tool electrode 100 in the present embodiment, the electrolyte solution can be circulated only in the target machining area, so that the tool electrode need not be supported in the vertical direction. For example, if the holder that holds the tool electrode includes a moving mechanism such as a robot hand that can approach the fixed workpiece from the direction different from the vertical direction, Processing can proceed in a direction different from the direction.

  Further, in the present embodiment described above, the tool electrode 100 having a double cylindrical structure has been described, but the structure of the tool electrode is not limited to a combination of two cylinders. The first inner hole and the second inner hole may be formed in the metal rod by drilling. In this case, it is preferable that the discharge port of the first inner through hole is provided on the peripheral side at the tip portion than the suction port of the second inner through hole. Further, the tool electrode is not limited to a cylindrical shape, and various shapes can be adopted.

  FIG. 8 is an external perspective view of another tool electrode 800. In the figure, a part of the internal structure is shown by a thin line so that the route of the electrolytic solution can be understood. The tool electrode 800 can be attached to the electrolytic processing apparatus 10 in place of the tool electrode 100.

  The tool electrode 800 mainly includes a center plate 810, a first sandwiching plate 820 and a second sandwiching plate 830 that sandwich the center plate 810, a base plate 850 that supports these three plates, and a base plate 850 comprising the three plates. It is comprised by the fixed block 840 fixed to.

  The center plate 810 is a substantially square thin plate, and a first slit 811 and a second slit 812 are formed from one common side. The first slit 811 and the second slit 812 are formed so that the center plate 810 is sandwiched between the first sandwiching plate 820 and the second sandwiching plate 830 so that the first through hole for supplying the electrolyte solution 550 and the electrolyte solution 550 are provided. It functions as a second inner through hole to be collected. The openings on the one side function as a discharge port 8111 for discharging the electrolytic solution 550 and a suction port 8121 for sucking the electrolytic solution 550, respectively.

  A supply port 8112 that is the end opposite to the supply port 8112 in the first slit 811 communicates with the first connection hole 861. The first connection hole 861 is a cylindrical hole formed across the central plate 810, the first sandwiching plate 820, and the second sandwiching plate 830, and the supply tube 561 is inserted into the first connection hole 861 and fitted therein. Match. Therefore, the electrolytic solution 550 supplied via the supply tube 561 can reach the discharge port 8111 through the inside of the tool electrode 800.

  Similarly, the recovery port 8122 that is the end opposite to the suction port 8121 in the second slit 812 communicates with the second connection hole 862. The second connection hole 862 is a cylindrical hole formed across the central plate 810, the first clamping plate 820, and the second clamping plate 830, and the above-described recovery tube 562 is inserted into the second connection hole 862 and fitted. Match. Therefore, the electrolytic solution 550 sucked from the suction port 8121 can reach the collection tube 562 through the inside of the tool electrode 800.

  The fixing block 840 is a clamp member that presses the three overlapped plates (the central plate 810, the first clamping plate 820, and the second clamping plate 830) toward the base plate 850 by screwing the screws 841, and fixes them to the base plate 850. It is. In the present embodiment, the fixing block 840 is used for clamping, but various variations can be adopted for the fixing structure. For example, a configuration may be employed in which a screw is screwed into the base plate 850 through the three stacked plates from the side of the first clamping plate 820 located on the side opposite to the base plate 850.

  Base plate 850 is fixed to holder 400 via screws 851. The fixing is not limited to screws, and for example, a fixing structure having compatibility with other general tool electrodes can be adopted by forming a part of the base plate 850 into a cylindrical shape.

  In addition, the tool electrode 800 should just be the conductor according to the workpiece 200 in which the center plate 810 made to function as an electrode at least. About other members, you may employ | adopt insulators, such as resin.

  FIG. 9 is an explanatory diagram for explaining a method of manufacturing the tool electrode 800. FIG. 9A is a diagram showing a slit forming process for forming the first slit 811 and the second slit 812 in the central plate 810. The first slit 811 and the second slit 812 are formed by wire electric discharge machining. Therefore, since the width is approximately the wire diameter of the discharge wire, the discharge wire is appropriately selected according to the target circulating amount of the electrolyte.

  As shown in the figure, the discharge wire forming the first slit 811 advances in the direction of about 45 degrees from the approximate center of one side forming the outer edge of the central plate 810, and advances from the middle toward the opposite side. The discharge wire stops before reaching the opposite side. The end point on the one side becomes the discharge port 8111 when assembled as the tool electrode 800, and the other end point becomes the supply port 8112.

  Similarly, the discharge wire that forms the second slit 812 is approximately 45 degrees opposite to the traveling direction of the first slit 811 from the point that is approximately the center of the one side and slightly away from the discharge port 8111. Proceeds and proceeds from the middle toward the opposite side. The discharge wire stops before reaching the opposite side. The end point on the one side becomes the suction port 8121 when assembled as the tool electrode 800, and the other end point becomes the recovery port 8122. The plate pressure of the central plate 810 is, for example, 0.1 mm.

  FIG. 9B is an exploded perspective view showing the assembly process of the tool electrode 800, particularly the inner through hole forming process. First, the center plate 810 is sandwiched between the first sandwiching plate 820 and the second sandwiching plate 830 and the mutual position is adjusted. At this time, they may be bonded to each other so that their positions are not displaced. The three plates whose positions have been adjusted are pressed against the base plate 850 side by a fixing block 840 and fixed by screws 841. By being sandwiched between the two clamping plates in this way, a first inner through hole for supplying the electrolytic solution 550 and a second inner through hole for collecting the electrolytic solution 550 are formed.

  FIG. 9C is a diagram showing a flow path forming process for forming the first connection hole 861 and the second connection hole 862. The central plate 810, the first clamping plate 820, and the second clamping plate 830 that are fixed and integrated are mounted on the drilling machine together with the base plate 850, and a first connection hole 861 and a second connection hole 862 are formed by the drill 910, respectively. The At this time, since the central plate 810 is thinner than the first clamping plate 820 and the second clamping plate 830, the first connection hole 861 and the second connection hole 862 are the first clamping plate 820 and the second clamping plate. 830 is formed across at least one of 830. As described above, the supply tube 561 and the recovery tube 562 are inserted and fitted into the formed first connection hole 861 and second connection hole 862, respectively.

FIG. 10 is an enlarged view of the tip portion of the tool electrode 800. As illustrated, the aperture length of the discharge port 8111 is _{g i,} for example, 0.2 mm. The opening length of the suction port 8121 is _{g o,} for example, 1.0 mm. As in this embodiment, when the opening length of the suction port 8121 is larger than the opening length of the discharge port 8111, that is, when the opening area of the suction port is larger than the opening area of the discharge port, the circulation of the electrolyte 550 is smooth. It becomes.

Between the suction port 8121 and the discharge port 8111 is a region where the electrolytic solution 550 circulates, and is a processing region where the electrolytic processing proceeds substantially. This interval is appropriately set according to the processing accuracy for performing the electrolytic processing. Further, in this processing region, it is preferable to slightly retract so as to be offset with respect to one side of the central plate 810. Offset in the example of figure is _{g w,} for example, 0.02 mm. By providing such an offset, the circulation of the electrolyte 550 becomes smoother. Further, the surface may be plated with gold, silver or the like so that the electrode does not dissolve in the processing region.

  In the above example, the center plate 810, the first sandwiching plate 820, and the second sandwiching plate 830 have been described as being substantially the same square, but the shape is not limited thereto. For example, a substantial machining area in the vicinity of the suction port 8121 and the discharge port 8111 may be protruded toward the workpiece. If the substantial machining area is projected, the tool electrode 800 can be easily moved in the xy direction during machining.

  Next, variations of the entire electrolytic processing machine will be described. FIG. 11 is a conceptual diagram conceptually showing another electrolytic processing apparatus 20. Although the above-described electrolytic processing apparatus 10 has one tool electrode that can be mounted, the electrolytic processing apparatus may be configured so that a plurality of tool electrodes can be mounted. The electrolytic processing apparatus 20 is an example of a configuration in which two tool electrodes can be mounted. The same elements as those of the electrolytic processing apparatus 10 of FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  As described above, when the electrolytic solution is circulated at the tip of the tool electrode, the area of the surface of the workpiece in contact with the electrolytic solution greatly affects the processing speed and processing accuracy. Therefore, for example, if machining is performed by combining a tool electrode that circulates a large amount of electrolytic solution and a tool electrode that circulates a small amount of electrolytic solution, both high-speed rough machining and high-precision finishing can be achieved.

  In addition, when both the addition process and the removal process are performed, it is possible to employ a tool electrode that is optimal for the addition process and one that is optimal for the removal process. That is, the additional processing is performed using a tool electrode optimum for the additional processing, and the removal processing is performed using a tool electrode optimal for the removal processing. By dedicating the tool electrode used in addition processing and removal processing in this way, even when using a common electrolyte, the tool electrode does not dissolve, and the deposited metal adheres to the tool electrode. It is possible to realize electrolytic processing that does not occur.

  The electrolytic processing apparatus 20 includes a first tool electrode 1001 and a second tool electrode 1002. The first tool electrode 1001 is a metal tool electrode including a first supply port 1201 for supplying the electrolytic solution 550 and a first recovery port 1301 for recovering the electrolytic solution 550. The electrolytic solution 550 is discharged from the first tip portion 1101, which is an end surface facing the planned machining position 210 of the workpiece 200, toward the planned machining position 210, and is collected again from the first tip portion 1101. The first tool electrode 1001 is attached to the first holder 4001 in a replaceable manner.

  The first recovery port 1301 is connected to the pump 500 via the first recovery tube 5621. The first supply port 1201 is connected to the tank 520 via the first supply tube 5611. The first supply tube 5611 is connected so as to be filled with the electrolytic solution 550 even when the electrolytic processing apparatus 20 is stopped. When the first tool electrode 1001 is used, the circulation path of the electrolyte 550 is as follows: tank 520 → first supply tube 5611 → first tool electrode 1001 (first supply port 1201 → first tip 1101 → first recovery). Mouth 1301) → first recovery tube 5621 → pump 500 → filtering device 580 → refluxing tube 563 → (tank 520).

  The first holder 4001 is pivotally supported by a first support 4101 fixed along the z-axis direction, and the first support 4001 is driven by a first driving unit 4201 provided integrally with the first holder 4001. Move 4101 up and down. Accordingly, the first tool electrode 1001 moves forward and backward with respect to the workpiece 200 as the first holder 4001 moves up and down. The first drive unit 4201 is configured by a motor including a gear mechanism that meshes with the first support column 4101, for example.

  The second tool electrode 1002 is a metal tool electrode including a second supply port 1202 that supplies the electrolytic solution 550 and a second recovery port 1302 that collects the electrolytic solution 550. The electrolytic solution 550 is discharged from the second tip portion 1102, which is an end surface facing the planned machining position 210 of the workpiece 200, toward the planned machining position 210, and is collected from the second tip portion 1102 again. The second tool electrode 1002 is replaceably attached to the second holder 4002.

  The second recovery port 1302 is connected to the pump 500 via the second recovery tube 5622. The second supply port 1202 is connected to the tank 520 via the second supply tube 5612. The second supply tube 5612 is connected so as to be filled with the electrolytic solution 550 even when the electrolytic processing apparatus 20 is stopped. When the second tool electrode 1002 is used, the circulation path of the electrolytic solution 550 is as follows: tank 520 → second supply tube 5612 → second tool electrode 1002 (second supply port 1202 → second tip 1102 → second recovery). Mouth 1302) → second recovery tube 5622 → pump 500 → filtering device 580 → reflux tube 563 → (tank 520).

  The second holder 4002 is pivotally supported by a second support 4102 fixed along the z-axis direction, and the second support 4002 is driven by a driving force of a second drive unit 4202 provided integrally with the second holder 4002. Move 4102 up and down. Therefore, the second tool electrode 1002 advances and retreats with respect to the workpiece 200 as the second holder 4002 moves up and down. The second drive unit 4202 is configured by a motor including a gear mechanism that meshes with the second support post 4102, for example.

  The stage 300 is placed on the guide rail 320 and freely moves in the xy direction. The movement of the stage 300 in the xy direction is controlled by the CPU 710. In particular, the stage 300 is opposed to the tip of the tool electrode that is newly used from the position facing the tip of the tool electrode that has been used so far, in synchronization with the timing at which the tool electrode used for machining is switched. Move to the position you want.

  The first tool electrode 1001 and the second tool electrode 1002 are connected by the tool connection line 621 and kept at the same potential. With this configuration, the power source 600 does not need to be provided with a changeover switch, and thus a simple circuit configuration can be employed. Of course, the power source 600 may be provided with a changeover switch so that the tool connection line is connected to each tool electrode so that the CPU 710 can control the potentials of the first tool electrode 1001 and the second tool electrode 1002 independently. . With this configuration, the CPU 710 can control, for example, the first tool electrode 1001 for additional machining and the second tool electrode 1002 for removal machining.

  In the present embodiment, since the electrolytic solution 550 is circulated using the Benchery effect, the pump 500 and the tank 520 can be shared with respect to the two tool electrodes. That is, when the tool electrode to be processed is brought close to the workpiece 200, the electrolytic solution 550 starts to circulate at the tip thereof, and when the tool electrode not to be processed is separated from the workpiece, the pump 500 sucks. However, the electrolytic solution 550 does not circulate or scatter. Therefore, in this embodiment, it is not necessary to provide a plurality of pumps 500 and tanks 520, so that the entire configuration of the electrolytic processing apparatus 20 can be simplified.

  FIG. 12 is a conceptual diagram conceptually showing another electrolytic processing apparatus 30. Although the above-described electrolytic processing apparatus 10 has one type of electrolytic solution to be circulated, a plurality of types of electrolytic solution may be selectively circulated. The electrolytic processing apparatus 30 is an example of a configuration that can circulate two types of electrolytic solutions. The same elements as those of the electrolytic processing apparatus 10 of FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  In the electrolytic processing apparatus, the selection of the electrolytic solution greatly affects the processing speed and processing accuracy. Therefore, for example, by selectively using a combination of an electrolytic solution that has a fast electrolytic reaction but difficult to control accuracy and an electrolytic solution that has a slow electrolytic reaction but easy control of accuracy, high-speed roughing and high-precision finishing are possible. Processing can be compatible. For example, a copper sulfate solution can be used as the former electrolytic solution, and a copper nitrate solution can be used as the latter electrolytic solution.

  Moreover, when performing an addition process and a removal process together, the optimal electrolyte solution can also be employ | adopted for each. In this way, by specializing the electrolyte used for addition processing and removal processing, even when a common tool electrode is used, the tool electrode does not dissolve, and the deposited metal adheres to the tool electrode. It is possible to realize electrolytic processing that does not occur. For example, a copper nitrate solution can be used as the former electrolytic solution, and a sodium nitrate solution can be used as the latter electrolytic solution.

  The first pump 5001 is a suction pump that sucks the first electrolytic solution 5501 connected to the switching valve 570 via the first recovery tube 5621. The first electrolytic solution 5501 is, for example, a sodium nitrate solution used for removal processing. The first recovery tube 5621 has the same performance as the suction pump 500 described with reference to FIG. The first pump 5001 includes a first pressure gauge 5101, and the first pressure gauge 5101 outputs the suction pressure of the first electrolyte 5501. During processing, the CPU 710 receives the output of the first pressure gauge 5101 and monitors the suction pressure of the first electrolyte 5501.

  The collected first electrolyte 5501 is sent to the first filtration device 5801 to filter impurities. When using an electrolytic solution that does not require concentration adjustment during circulation, it is not necessary to provide a concentration adjusting device as described with reference to FIG. 1, but when using an electrolytic solution whose concentration changes during processing. A density adjusting device may be provided. The filtered first electrolyte 5501 is sent to the first tank 5201 and stored.

  The first tank 5201 is a container that stores the first electrolytic solution 5501. One end of a first supply tube 5611 is connected to the first tank 5201, and the other end of the first supply tube 5611 is connected to a switching valve 570.

  The second pump 5002 is a suction pump that sucks the second electrolytic solution 5502 connected to the switching valve 570 via the second recovery tube 5622. The second electrolytic solution 5502 is, for example, a copper nitrate solution used for additional processing. The second recovery tube 5622 has the same performance as the suction pump 500 described with reference to FIG. The second pump 5002 includes a second pressure gauge 5102, and the second pressure gauge 5102 outputs the suction pressure of the second electrolyte 5502. During processing, the CPU 710 receives the output of the second pressure gauge 5102 and monitors the suction pressure of the second electrolyte 5502.

  The recovered second electrolytic solution 5502 is sent to the second filtration device 5802 to filter impurities. At this time, as described with reference to FIG. 1, the density adjustment may be performed by providing the density adjustment device 581. The filtered second electrolyte 5502 is sent to the second tank 5202 and stored.

  The second tank 5202 is a container that stores the second electrolytic solution 5502. One end of a second supply tube 5612 is connected to the second tank 5202, and the other end of the second supply tube 5612 is connected to a switching valve 570.

  The switching valve 570 includes a valve mechanism that switches whether the first electrolytic solution 5501 is circulated or the second electrolytic solution 5502 is circulated. The valve mechanism of the switching valve 570 is driven by the control of the CPU 710. More specifically, the switching valve 570 is connected to the other end of the supply tube 561 whose one end is connected to the supply port 120 of the tool electrode 100. The valve mechanism includes the supply tube 561 and the first supply tube. Either 5611 or the second supply tube 5612 is connected. The switching valve 570 is connected to the other end of a recovery tube 562 having one end connected to the recovery port 130 of the tool electrode 100. The valve mechanism includes a recovery tube 562, a first recovery tube 5621, and a second recovery tube 5621. Any of the collection tubes 5622 is connected. At this time, the valve mechanism causes the collection tube 562 and the first collection tube 5621 to communicate with each other when the supply tube 561 and the first supply tube 5611 are communicated. Similarly, when the supply tube 561 and the second supply tube 5612 are communicated, the collection tube 562 and the second collection tube 5622 are communicated.

  With this configuration, when the first electrolyte 5501 is used, the circulation path is as follows: first tank 5201 → first supply tube 5611 → switching valve 570 → supply tube 561 → tool electrode 100 (supply port 120 → tip 110 → recovery port 130) → recovery tube 562 → switching valve 570 → first recovery tube 5621 → first pump 5001 → first filtration device 5801 → (first tank 5201). Similarly, when the second electrolytic solution 5502 is used, the circulation path is as follows: the second tank 5202 → the second supply tube 5612 → the switching valve 570 → the supply tube 561 → the tool electrode 100 (the supply port 120 → the tip 110). → recovery port 130) → recovery tube 562 → switching valve 570 → second recovery tube 5622 → second pump 5002 → second filtration device 5802 → (second tank 5202).

  As described above, the example of selectively using a plurality of tool electrodes using FIG. 11 and the example of selectively circulating a plurality of types of electrolytes using FIG. 12 have been described. An electrolytic processing apparatus can also be configured. If a plurality of types of electrolytes can be circulated through each of a plurality of tool electrodes, a wider variety of processing can be realized effectively.

  Next, variations of the applied voltage will be described. In each of the above examples, pulse application control is performed in which one of the tool electrode and the workpiece is set to the ground potential and the other is set to the positive potential. However, the application control is not limited to this.

  It is known that the machining accuracy improves if pulse application control is performed. For example, in the removal machining, if ON and OFF are repeated between 0 and + V volts, an instantaneous overshoot occurs at the fall of the pulse. Negative potential. In the pulse application control, ON and OFF are repeated many times in a short time, so that the accumulated time for a negative potential is increased, resulting in melting of the tool electrode. The same applies to the additional machining that repeatedly turns on and off between 0 V and −V volts, and there may be a momentary positive potential due to overshoot at the rise of the pulse. In this case, as a result, metal is deposited on the tool electrode. That is, when pulse application control is performed with reference to 0 volts, the tool may be consumed. Until now, in order to avoid the consumption of the tool electrode, direct current application control has been performed instead of pulse application control.

Variations of application control in this embodiment will be described. FIG. 13 is a diagram illustrating an example of an applied voltage according to the variation. For example, when a positive potential pulse is applied in the removal process, the CPU 710 can control the ground potential to be slightly increased to provide a positive offset voltage. In this case, as shown in the figure, the high level voltage is V _HI , the low level voltage is V _LO, and a fixed stop time is provided for each X _p pulse. Specifically, when setting the V _HI to about 10V, V _LO is that may be, for example, about 2V in the range of about 30% from 10% of V _HI was found experimentally. In this way, if the offset voltage is provided on the same polarity side, the possibility that the potential is inverted at the fall of the pulse is reduced, and thus the consumption of the tool electrode can be avoided.

  Further, if the tool electrode is vibrated during a certain stop time, impurities adhering to the tool electrode can be removed or the electrolytic solution can be stirred. Specifically, when the piezoelectric element attached to the tool electrode is controlled by the CPU 710, the tool electrode can be vibrated in synchronization with the stop time.

  In the above embodiment, when additional processing is performed, if a specific metal thin film is formed on the surface, a coloring effect by thin film interference can be obtained. According to this embodiment, since a thin film can be partially formed, a coloring effect can be applied to a specific portion of a three-dimensional shape.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

10, 20, 30 Electrolytic processing apparatus, 100 Tool electrode, 110 Tip portion, 120 Supply port, 121 First inner through hole, 130 Recovery port, 131 Second inner through hole, 140 Outer tube, 141 Outer tube tip, 150 Inner cylinder, 151 Inner cylinder tip, 160 O-ring, 171 discharge port, 172 suction port, 200 workpiece, 210 planned machining position, 220 workpiece, 300 stage, 310 chuck, 400 holder, 410 strut, 420 drive unit, 500 Pump, 510 Pressure gauge, 520 Tank, 550 Electrolyte, 561 Supply tube, 562 Recovery tube, 563 Reflux tube, 580 Filtration device, 581 Concentration adjustment device, 600 Power supply, 601 Indicator, 610 Workpiece connection line, 620 Tool connection Line, 700 control unit, 710 CPU, 720 operation Panel, 800 Tool electrode, 810 Center plate, 811 1st slit, 8111 Discharge port, 8112 Supply port, 812 2nd slit, 8121 Suction port, 8122 Collection port, 820 1st clamping plate, 830 2nd clamping plate, 840 fixation Block, 841 screw, 850 base plate, 851 screw, 861 first connection hole, 862 second connection hole, 910 drill, 1001 first tool electrode, 1002 second tool electrode, 1101 first tip, 1102 second tip, 1201 1st supply port, 1202 2nd supply port, 1301 1st collection port, 1302 2nd collection port, 320 guide rail, 4001 1st holder, 4002 2nd holder, 4101 1st support, 4102 2nd support, 4201 1st 1 drive unit, 4202 second drive unit, 621 5001 1st pump, 5002 2nd pump, 5101 1st pressure gauge, 5102 2nd pressure gauge, 5201 1st tank, 5202 2nd tank, 5501 1st electrolyte, 5502 2nd electrolyte, 5611 1st 1 supply tube, 5612 2nd supply tube, 5621 1st recovery tube, 5622 2nd recovery tube, 570 switching valve, 5801 1st filtration device, 5802 2nd filtration device

Claims (23)

A tool electrode provided with a first inner hole for discharging the electrolyte toward the tip and a second inner hole for sucking the electrolyte from the tip;
An application unit that applies a voltage so that a potential of the tool electrode is increased with respect to a workpiece placed opposite to the tip part;
A control unit that deposits metal on the surface of the workpiece by performing circulation control of the electrolytic solution and voltage control of the application unit ;
A circulation path for guiding the electrolyte sucked from the second inner through hole to the first inner through hole;
A suction pump for circulating the electrolyte using suction force;
A pressure detector for detecting the pressure of the suction pump;
An electrolytic processing apparatus comprising: a distance adjusting unit that separates the tool electrode from the workpiece based on the change in the pressure . The electrolytic processing apparatus of Claim 1 provided with the density | concentration adjustment part which maintains the density | concentration of the said electrolyte solution constant. The electrolytic processing apparatus according to claim 1, further comprising a moving mechanism that moves the tip portion toward the surface of the workpiece. The tool electrode, the discharge port of the first betrayer hole than said suction port of the second betrayer hole, to any one of claims 1 to 3 provided on the peripheral side at the tip portion The electrolytic processing apparatus as described. 5. The electrolytic processing apparatus according to claim 4, wherein the tool electrode has a peripheral side protruding from the inner peripheral side toward the workpiece at the tip end portion from the inner peripheral side. The electrolytic processing apparatus according to claim 4 , wherein the tool electrode has an area of the suction port larger than an area of the discharge port. The tool electrode includes an inner cylinder that forms the second inner through hole, and an outer cylinder that passes through the inner cylinder and forms the first inner through hole between the inner cylinder and the inner cylinder. The electrolytic processing apparatus according to any one of 6 . The electrolytic processing apparatus according to claim 7, wherein the tool electrode has a flange portion in which an inner cylinder tip portion of the inner cylinder, which is a part of the tip portion, extends in an outer cylinder direction. Wherein at least either the first betrayer hole and the second betrayer hole, either a central plate which slit is provided, claim 1, which is formed by sandwiching plate supporting sandwich the center plate 7 of The electrolytic processing apparatus according to item 1. The application unit has an inversion unit that inverts the polarity and applies a voltage so that the potential of the workpiece becomes higher with respect to the tool electrode,
Wherein, electrolytic processing apparatus according to any one of claims 1 to 9 for dissolving the metal of said surface by controlling the inversion unit. The said distance adjustment part is an electrolytic processing apparatus of Claim 10 which adjusts the distance of the said tool electrode and the said workpiece using the threshold value of a mutually different pressure for every polarity applied to the said tool electrode. The electrolysis according to any one of claims 1 to 11, further comprising a switching mechanism that switches the electrolytic solution that flows through the first and second internal through holes from the first electrolytic solution to the second electrolytic solution. Processing equipment. Electrolytic processing apparatus according to any one of claims 1 to 12 including a plurality of different said tool electrode. The electrolytic processing apparatus according to any one of claims 1 to 13, wherein the control unit executes pulse voltage control in which an offset voltage and a pulse voltage having a larger absolute value than the offset voltage are applied to the same polarity side . An approach process for bringing the tool electrode closer to the workpiece;
A circulation step of circulating an electrolyte using suction force in the order of the inside of the tool electrode, the tip of the tool electrode and the surface of the workpiece, and the inside of the tool electrode;
Applying a voltage so as to increase the potential of the tool electrode with respect to the workpiece, and depositing a metal on the surface of the workpiece ;
A distance adjusting step of separating the tool electrode from the workpiece based on a change in pressure for sucking the electrolytic solution . The electrolytic processing method according to claim 15, wherein the circulating step causes the electrolytic solution to flow from a peripheral side to a central side at the tip portion. In the circulation step, the electrolysis is performed using a Benchery effect generated by a cross section of a flow path formed between the tip of the tool electrode and the surface of the workpiece being smaller than a cross section of another flow path. The electrolytic processing method according to claim 15 or 16, wherein the liquid is circulated. The electrolytic processing method according to claim 17, wherein in the circulation step, the electrolytic solution stays inside the tool electrode until the electrolytic solution is circulated by the Benchery effect. The electrolytic processing method according to any one of claims 15 to 18, further comprising a concentration adjusting step of keeping the concentration of the electrolytic solution constant. 20. The method according to claim 15 , further comprising a melting step of reversing the polarity and applying a voltage to the tool electrode so as to increase the potential of the workpiece to melt the metal on the surface of the workpiece. The electrolytic processing method according to item. 21. The electrolytic processing method according to claim 20, wherein, in the distance adjusting step, the distance between the tool electrode and the workpiece is adjusted by using different pressure thresholds for each polarity applied to the tool electrode. The electrolytic processing method according to any one of claims 15 to 21, further comprising a switching step of switching the electrolytic solution from the first electrolytic solution to the second electrolytic solution. The electrolytic processing method according to any one of claims 15 to 22, further comprising a changing step of changing the tool electrode to which a voltage is applied.

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