JPH01188230A - Finishing method based on electrochemical machining and its device - Google Patents

Abstract

PURPOSE:To improve the surface roughness of a finished work to steadily obtain a highly accurate surface quality in a short time by establishing electrical energy per unit area according to the size of an area to be mashined, namely less for a large area than a small one. CONSTITUTION:A power source of an electrochemical finishing device 1 is turned on, and an input device 13 aligns an electrode 2 with a work 4, and inputs parameters such as a gap between the electrodes, an area to be machined, mulching depth, and the roughness of a surface 4a to be finished before finishing. Next, a machining condition control section 10 establishes electrical energy per unit area according to the size of the area to be machined, namely less for a large area than a small one, and applies pulse voltage from a power source device 8 to the electrode 2. The electrode 2 is then raised through a motor driving control section 9, and the electromagnetic valve of an electrolyte filtering device 14 is actuated to make the electrolyte blow off through a nozzle 80 for the removal of an electrolytic product. The above-mentioned operations are repeated to finish the work 4. Thus a high quality finished surface such as a glossy face can be easily obtained.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a finishing method and an electrolytic finishing device using electrolytic machining, and particularly for finishing a three-dimensionally shaped work surface in a short time and with high precision. The present invention relates to an electrolytic finishing method and an electrolytic finishing apparatus that provide a mirror-like glossy surface.

[Prior Art] An electrolytic processing method is known as a conventional metal processing method. In this electrolytic processing method, the gap between the workpiece and the electrode is filled with an electrolytic solution such as sodium nitrate or sodium chloride, and this electrolytic solution is flowed at high speed. This process involves passing a direct current from the workpiece to the electrode while removing metal compounds, metal ions, hydrogen gas, etc. (Unexamined Japanese Patent Publication No. 61-7
1921 and Japanese Patent Laid-Open No. 60-44228) [Problems to be Solved by the Invention] However, this electrolytic machining method has a fatal flaw as a machining means. In other words, especially in bottom processing of a three-dimensional shape (meaning processing of a three-dimensional structure formed in the shape of a concave hole), even if the gap between the workpiece and the electrode is constant, the amount of electrolyte location of the inlet,
The flow path resistance of the gap changes depending on the distance from the inlet or the degree of curvature of the three-dimensional surface of the workpiece, making it impossible to flow the electrolytic solution into the gap at a similar flow rate.

Therefore, the removal of electrolytic products generated in the gap differs depending on the position, causing differences in the progress of processing and making it difficult to accurately transfer the electrode to the workpiece. If quality is desired, another polishing process is required, which is disadvantageous in that it takes a lot of time and effort to finish the surface to be machined.

Therefore, in order to eliminate these inconveniences, Kanto Toyama devised a solution that could be applied to the workpiece by keeping the electrolyte in a static state and supplying a pulsed current with a low current density between the electrode and the workpiece during the early stage of finishing. In addition to improving the surface roughness of the surface, pulsed current with high current density is intermittently supplied during this machining to remove the oxide film that forms on the processed surface during machining, and in the later stages of finishing. An application was filed (see Japanese Patent Application No. 117486/1986) for a finishing method using electrolytic processing to obtain a glossy surface by supplying a pulsed current with a high current density.

However, in this finishing method using electrolytic machining, the surface roughness of the processed surface can be improved by using a pulsed current with a low current density in the early stage of finishing, but the improvement in surface roughness varies depending on the size of the processing area. This has caused the problem that highly accurate surface quality cannot be stably obtained, especially when the processing area is large.

Therefore, the purpose of the present invention is to improve the surface roughness of the processed surface regardless of the size of the processed area, and to achieve electrolytic processing that can stably obtain high-precision surface quality in a short time. The purpose of the present invention is to realize a finishing method and an electrolytic finishing device.

[Means for Solving the Problem] In order to achieve this object, the first invention of this application applies pulsed electrical energy between an electrode and a workpiece that are disposed opposite each other via a stationary electrolyte. and setting the machining area of the workpiece, and changing the electrical energy according to the size of the machining area, and adjusting the electrical energy per unit area when the machining area is large. is characterized by comprising the steps of setting the area smaller than in the case of a small area, and removing electrolytic products generated between the electrodes, and the second invention is characterized in that the electric energy is changed depending on the size of the machining area. is in the range of 0.06 coulombs/cm2 to 0.3 coulombs/cm2. Further, a third invention provides a pulse supply means for supplying pulsed electrical energy between poles of a workpiece and an electrode disposed opposite each other via a stationary electrolytic solution, and setting a processing area of the workpiece. a machining area setting means; and a pulse supplying means for changing the electrical energy according to the size of the machining area so that the electric energy per unit area is smaller when the machining area is large than when the machining area is small. It is characterized by comprising a control means for controlling the electrolytic product, and an electrolytic product removing means for removing the electrolytic product generated between the electrodes.

[Function] According to the configuration of the present invention, when the processing area of the workpiece is small, for example, about 1 cm2, a larger pulse-like electric energy consisting of current density and pulse width, for example 0.
．． With electrician energy of 3 coulombs/cm2,
If the processing area is large, e.g. 3000 m2, smaller electrical energy, e.g. 0.06 coulombs/cm
The electrical energy of step 2 improves the surface roughness of the processed surface in a short time.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail and specifically with reference to the drawings.

1 to 7 show one embodiment of this invention.

In Figure 1.2, the electrolytic finishing device l has an electrode 2
an electrode fixing device 3 that fixes the workpiece 4, a workpiece fixing device 5 that fixes the workpiece 4, a drive conversion section 7 that converts the rotational motion of the electrode drive section 6 into reciprocating motion, a power supply device 8 that generates a pulse current, and a motor. A control device 12 consisting of a drive control section 9, a processing condition control section IO, an electrolyte flow control section 11, etc., a manual device 13 for inputting various data regarding the workpiece 4, an electrolyte filtration device 14 for filtering the electrolyte, It consists of a processing tank 15, etc.

The electrode fixing device 3 has an electrode 2 made of, for example, pure copper or graphite attached to the lower end of a rod 16 provided at its lower part, so that the electrode surface 2a and the processed surface 4a of the workpiece 4 are aligned three-dimensionally. It is fixed so that a gap 17 is maintained. The electrode fixing device 3 is moved up and down by the electrode driving section 6 and the drive conversion section 7 to set the gap 17 to a predetermined value. That is, the rotary encoder 18 of the electrode drive unit 6
A control signal output from the motor drive control section 9 in response to a signal from the tachogenerator 19 controls the rotation of the motor 2° to move the electrode fixing device 3 up and down, thereby separating the electrode surface 2a and the workpiece surface 4a. is set to a predetermined gap 17.

The workpiece fixing device 5 is a table made of highly insulating granite or ceramics, and is connected to the electrolytic processing device 10.
It is fixed together with the bottom plate of the processing tank 15 on the X table (not shown) of the X-Y table 21 with bolts or the like. Also,
The workpiece 4 is fixed to the upper surface of the workpiece fixing device 5 by bolts 22, etc., and the workpiece 4, the workpiece fixing device 5, and the processing tank 15 are moved by the X-Yf-pull 21. By rotating the knobs 23 and 240, they move integrally in the X direction and the X direction.

A power supply device 8 serves as a pulse supply means for supplying a predetermined pulsed electrical energy (amount of coulombs per unit area) between the electrode 2 and the workpiece 4, and the power supply device 8 controls the power supply device 8. The processing condition control section 10 of the control device 12 is configured as shown in FIG. 3, for example.

That is, the power supply device 8 includes a DC power supply unit 25 and a charging/discharging unit 26, and the DC power supply unit 25 includes a transformer 27 and a rectifier 28.
The voltage is lowered to a predetermined value by a transformer 27 and rectified by a rectifier 28 to obtain a direct current, which is supplied to capacitors 29-1 to 29-n, which will be described later.

The charging/discharging unit 26 also includes a plurality of capacitors 29-1 to 29-n that discharge charges between electrodes, and each of these capacitors 29-
Diodes 30-1 to 30-n connected to diodes 30-1 to 29-n to prevent backflow of charges to the DC power supply section 25 side, and a discharge switch 31-n that is opened and closed to discharge charges to the discharge side.
1 to 31-n, and a charging switch 32 for supplying and disconnecting power from the DC power supply unit 25 to charge each of the capacitors 29-1 to 29-n to a predetermined value.

This power supply device 8 is operated according to the size of the machining area S of the workpiece 4 by a control signal from a machining condition control section 10, which will be described later.
5 (A/cm2) X4 (ms e c)
=0.06 coulomb/Cm2 to 100 (A/cm
2) X100 (ms e c) = 1O coulomb/
It is possible to supply machining energy of cm 2 to the space between the electrodes.

The machining condition control unit 10 that controls the charge/discharge unit 26 includes a voltage detector 33 that detects the charging voltage values of the capacitors 29-1 to 29-n, and a voltage detector 33 that detects the charging voltage values detected by the voltage detector 33 and D/ A voltage comparator 35 that compares the output value from the A converter 34, and a charging detector 36 that detects the completion and start of charging of the capacitors 29-1 to 29-n based on the output signal from the voltage comparator 35. , a current detector 37 that detects the current value of the charge discharged between the poles, a peak hold circuit 38 that holds the peak value of the current value detected by this current detector 37, and a peak hold circuit 38 that holds the current value detected by this current detector 37. A current comparator 40 that compares the peak current value and the output value of the D/A converter 39, a pulse generator 41 that generates a pulse with a predetermined time width, and a current that sets the current waveform of the charge discharged between the electrodes. A gate circuit 43 that outputs an opening/closing drive signal to each of the discharge switches 31-1 to 31n based on an input signal from the waveform setting device 42, and each of the capacitors 29-1 to 29-n.
a charging voltage setter 44 that sets a charging voltage value to be supplied to and outputs the signal to the D/A converter 34; and a charging voltage setting device 44 that sets a current value flowing between the electrodes and outputs the signal to the D/A converter 39. a current setting device 45 that operates, a CPU 46 that calculates and processes machining conditions based on the human power data of the input device 13, and a contact detector 47 that detects contact between the electrode 2 and the workpiece 4.
Consists of etc. Note that the reference numeral 48 in the figure indicates the discharge switch 311.
~31-n is opened, each discharge switch 31 is
This is a diode that prevents -1 to 31-n from being destroyed.

Note that the control of the CPU 46 when the capacitors 29-1 to 29-n are charged and discharged will be explained here. First, CP
U46 calculates the electric energy per kneading cycle (referring to machining using one pulse or several pulses) using a predetermined calculation formula based on the machining area S of the workpiece 4 manually entered in advance using the input device 13. At the same time, the peak current density of the pulse current required to obtain this electrical energy is calculated.

Then, a charging voltage value corresponding to this peak current density is calculated based on the characteristic table input to the storage device, and outputted to the charging voltage setter 44 of the processing condition control section 10.

When the capacitors 29-1 to 29-n are charged with a predetermined charging voltage value, a charging completion signal is input from the charging detector 36). Based on this signal, the CPU 46 outputs a control signal to the pulse generator 41 and the current waveform setter 42 to turn on the gate circuit 43 and discharge switches 31-1 to 31-1.
1-n is selectively turned on, and a predetermined pulse current is supplied between the electrodes. The current value of this pulse current is detected by the current detector 37, and the peak value at that time is the peak 71.
It is held by the cooled circuit 38. This held peak value is compared with a signal value obtained by converting the digital signal from the current setting device 45 into an analog signal by the D/A converter 39 in a current comparator 40, and the result is inputted to the CPU 46.

Based on the comparison result of the current comparator 40, the CPU 46 corrects the set voltage value of the charging voltage setter 44 (increases the set voltage value when the peak current value is less than the set current value; If it is larger, reduce the set voltage value)
The peak current value of the supplied pulse current is controlled to always be a predetermined value.

The input device 13 as a machining area setting means inputs various data regarding the workpiece 4 such as the machining area S1 and finishing machining margin, machining conditions, etc. For example, as shown in FIG. , keyboard 13
b, and an operation button section 13c. This will be explained below.

The keyboard 13b is used to select the manual operation mode and press the rMANJ (manual) key 50 when performing operations such as centering the electrode 2, discharging the electrolyte, and releasing residual charge, and the rJOGJ (jog) key 50 that selects the electrode 2 centering operation mode. ) key 5
1 and rsTEPJ (step) key 52, interrupts all operations during manual operation or automatic operation mode and returns to the initial state (power-on state) rR5TJ (
reset) key 53, the rJOGJ key 51 and rsT
rHIGf (high) key 54, rMID (middle) key 55, rLOWJ to set the raising and lowering speed and distance of the electrode 2 in combination with the EPJ key 52
(Low) key 56, used when centering the electrode 2,
When the electrode 2 is in contact with the workpiece 4, the electrode 2 is raised, and when it is separated from the workpiece 4, the electrode 2 is lowered rDTHRJ (dither) key 57, processing tank 1
rDRAI used when draining and circulating electrolyte from 5
NJ (drain) key 581, capacitors 29-1 to 29-
rDcHGJ (discharge) key 59 to discharge residual charge of n, rAUTO to select automatic operation mode
J (auto) key 60, rPTRN (pattern) key 61 to select the input screen necessary for machining, "RUN" key 62 to start automatic operation, rsTOPJ (stop) key to cancel automatic operation 63
, and "numeric" keys 64 for inputting various parameters.

Further, the operation button section 13c includes a "power button" 65 for turning on the power of the electrolytic finishing processing apparatus l, a "power off button" 66 for cutting off the power, and rUPJ.
(up) button 67 and rDWNJ (down)
It consists of a button 68. This "UP" button 67 and rD
When the "JOG" key 51 is on, the WNJ button 68 moves the electrode 2 (Z-axis) up and down for the length of time that the buttons 67 and 68 are held down, and when the rSTEPJ key 52 is on, When the buttons 67, 68 are pressed, the electrode 2 is raised and lowered by a certain distance. Further, the cut-off state of the "power off button" 66 is reset by rotating it to the right.

The electrolytic solution filtration device 14, which serves as an electrolytic product removal means, filters an electrolytic solution containing electrolytic products generated during processing, and is configured as shown in FIG. 5, for example.

That is, the electrolyte filtration device 14 includes a dirty tank 72 that stores the returned electrolyte containing a large amount of electrolytic products from the processing tank 15 via a solenoid valve 71, and a pump 73 that pumps up the electrolyte in the dirty tank 72. a centrifugal separator 74 that performs centrifugal separation, and a clean tank 7 that stores the electrolytic solution that does not contain electrolyzed products separated by the centrifugal separation 8174.
5, and a heater 83 built into this clean tank 75.
and a fan (not shown) rotated by a motor 84; a pump 77 that pumps up the electrolyte from the clean tank 75; and a pump 77 that pumps up the electrolyte from the clean tank 75, and passes the pumped electrolyte through a filter 78 before entering the processing tank 15. A solenoid valve 79 for supplying the electrolytic solution through a filter 78 is ejected by a jet nozzle 80 into the gap between the electrode 2 and the workpiece 4, and the electrolytic solution generated in the gap is removed. It consists of an electromagnetic valve 81, a stop valve 82 for returning the electrolytic solution that has passed through the filter 78 to the liquid temperature regulator 76, and the like.

In addition, 85.86 in FIG. 5 is a drive motor for the button 73.77, 87.88 is an upper limit float switch and a lower limit float switch for detecting the liquid level of the dirty tank 72,
9 is a float switch that detects the liquid level in the processing tank 15;
90 is a motor that drives the centrifugal separator 74.

Electrolyte flow control section 11 that controls this electrolyte filtration device 14
is for supplying an electrolytic solution into the machining tank 15 based on a control signal from the machining condition control unit 10, and for eliminating electrolytic products generated between the electrode surface 2a and the workpiece surface 4a during machining. Then, solenoid valves 79, 81, pumps 73, 77, etc. are controlled so that fresh electrolyte (temperature-adjusted electrolyte that has passed through filter 78) is spouted between electrode 2 and workpiece 4 by jet nozzle 80. do.

Next, an example of the finishing operation performed by the electrolytic finishing apparatus 1 will be explained with reference to the flowchart shown in FIG.

During finishing, for example, the electrode 2 used when electrical discharge machining the workpiece 4 or the remainder cut out by wire-cut electrical discharge machining is fixed to the lower end of the rod 16 of the electrode fixing device 3 as the electrode 2. , each of the workpieces 4 is attached to the workpiece fixing device 5, and the "power button" 65 is pressed to turn on the electrolytic finishing apparatus 1 (100). and rDcH of the human power device 13
Press the GJ key 59 to discharge the charges remaining in the capacitors 29-1 to 29-n (101), and center the electrode 2 and workpiece 4 (102). After that, the electrode gap δ,
Input parameters such as machining area S1 machining depth (machining allowance), machining front roughness of workpiece surface 4a, and machining conditions such as driving method of electrode 2 and method of applying electrolyte jet (103)
.

When the parameters etc. are entered manually and the rRUN key 62 is pressed, the electrode 2 descends and comes into contact with the surface to be processed 4a (104).
, this position is detected by the contact detector 47 and set as the origin A. Then, press the "rDRAIN" key 58 to operate the electromagnetic valve 79 of the electrolyte filtration device 14, and supply the electrolyte from the clean tank 75 into the processing tank 15 (105).
. When the electrolyte is supplied, the float switch 89 in the processing tank 15 is turned on and operation is started (106).
Workpiece 4 into which PU 46 is input by input device 13
Based on the machining area S of Charging voltage value, pulse width (on time of single pulse current), number of pulse supply N1
~N3, etc. are calculated using a conversion table or the like (107).

Then, raise the electrode 2 and set the electrode at a position that maintains the electrode gap δ manually input using the input device 108).
, when the electrolytic solution fills between the electrode surface 2a and the workpiece surface 4a and the electrolytic solution is stationary (referring to the state where the flow and movement of the electrolytic solution has almost stopped) (109), a predetermined electrical energy is obtained from the power supply device 8. peak current density jpx and pulse width to
A single pulse current (hereinafter referred to as the pulse current of box 1) for improving surface roughness having n1 is supplied between the electrode 2 and the workpiece 4 (110).

According to experiments, when the processing area S is 300 cm'', the electrical energy generated by the first pulse current has a peak current density jP1 of 15 A/cm'' and a pulse width t.

15 (A/c m2) X with nl of 4m5ec
4 (m sec ) =0.06 coulomb/cm2
When the processing area S is 1cm2, jPt is 60A/cm2 and tonnl is 5m5ec.
The surface roughness of the surface 4a to be machined can be significantly improved by electrical energy of 60X5=0°3 coulomb/cm", and when the machining area S is in the range of 1 to 300 cm2, the electrical energy and the machining area S It was confirmed that there is a substantially inversely proportional relationship.

After supplying the first pulse current between the electrodes, the motor 20 is driven by a signal from the motor drive control section 9 to raise the electrode 2 (111), and the electrode surface 2a is separated from the workpiece surface 4a, and the electrode surface The electrolytic products eluted between the electrolytic solution 2a and the processed surface 4a are ejected together with the electrolytic solution by ejecting the electrolytic solution from the ejection nozzle 8° by operating the electromagnetic valve 81 of the electrolytic solution filtering device 14 (112).

After removing the electrolysis products, the electrode 2 is lowered and the electrode surface 2
a comes into contact with the workpiece surface 4a (113), contact detector 4
7 to detect the position. This position and the origin A are
The machining depth per machining process was measured by comparing with PU46,
This is accumulated (114). Then, compare this cumulative value with a preset value set by the input device 13.
5) If the cumulative value of the machining depth does not reach a predetermined difference (for example, 1 μm) from the set value, it is determined whether the number of machining times is the predetermined number N1 (116). This judgment (116
), if No, return to step (108) and make judgment (1
Repeat until 16) becomes YES.

If YES in step (116), that is, if machining with the first pulse current has been performed a predetermined number of times N1,
The CPU 46 outputs a control signal to the charging voltage setting unit 44 to set the pulse current supplied from the power supply device 8 to a peak current density jP2 and a pulse width t on2 that provide higher electrical energy than the first pulse current. (117), and at the same time, raise the electrode 2 and set it at the same position as in the step (108) (118). . In this case, the gap between the electrode 2 and the workpiece 4 increases as the machining progresses. Then, when the electrolyte between the electrode 2a and the surface to be processed 4a becomes stationary (119), the second
A pulse current of 120 is supplied between the electrode 2 and the workpiece 4.
) The oxide film etc. that have been generated on the work surface 2a during the machining process - or several times is peeled off from the work surface 2a, and the electrode 2 is raised (121) The oxide film etc. is removed by the operation of the electromagnetic valve 81. (122). Note that this second pulse current has a peak current density of 5 to IOA/cm2 and a pulse width of 10 to 15 m s in addition to the first pulse current.
The value obtained by adding e c is optimal.

Once the oxide film and the like on the processed surface 4a are removed, the electrode 2 is lowered (123) and it is determined whether the predetermined number of processing times N2 has been reached (124). In this judgment (124), N
In the case of o, the process returns to step (118) and processing using the second pulse current is performed a predetermined number of times N2. Step (124
), the pulse current supplied from the power supply device 8 is switched to the first pulse current (125), and the process moves to step (108), where processing is performed to improve the surface roughness.

Through this series of machining, the cumulative value of the machining depth is compared with the set value, and when the cumulative value is within a predetermined difference with respect to the set value of the machining depth, YES is determined in step (115), and the machining conditions are The pulse current supplied from the power supply device 8 according to the control signal of the control unit 100 is set to a peak current density jP3 and a pulse width tO at which a predetermined electrical energy corresponding to the processing area S is obtained.
(126). Then, the step (118) described above with this third pulse current
Processing similar to steps 124 to 124 is repeated a predetermined number of times N3 (127) to 133, and all finishing processing is completed (134).

This third pulse current has a peak current density of 30 to 50
A pulse width of 20 to 60 msec at A/cm2 is optimal.

During machining using the first to third pulse currents, the display device 13a of the input device 13 displays, for example, the display shown in FIG. 7. That is, the input electrode gap δ (for example, G A P 100 μm), the machining area S (AREA
25cm2), machining allowance (D E P TH1μm
), machining front surface roughness (BEFORE 30 μm), remaining machining number of machining times N1 to N3 by each pulse current calculated in step (107) (COUNT=123), and machining cumulative time (TIMEOI: 23:450・1 hour 23)
minute 45 seconds) is displayed.

In the above embodiment, the machining area was set using the input device 13, but the present invention is not limited thereto. For example, the current value when a reference voltage is supplied between the electrodes is input to the current detector 37. The current value may be detected and automatically calculated and set by the CPU 46 based on this current value and a conversion formula determined in advance through experiments or the like.

Next, an example of machining performed under the following conditions using the electrolytic finishing method and electrolytic finishing apparatus I according to the present invention will be shown.

Electrode Pure copper Workpiece material Tool steel Electrode gap 0.1mm Machining fluid Sodium nitrate solution (concentration 40%)
) (Hereinafter, same page margin) As described above, in the electrolytic finishing method and electrolytic finishing apparatus 1 according to the present invention, the workpiece 4
If the processing area S is large, for example 300 cm,
Smaller electrical energy, e.g. 0.06 coulomb/
Cm2 of electric energy, and if the machining area S is small, for example 1 cm2, finishing machining is performed with larger electric energy, for example 0.3 ron/cm2, so the size of the machining area S Regardless, the surface roughness of the processed surface 4a can be improved, and the reason for this can be considered as follows.

That is, when pulsed electrical energy is supplied between the electrode 2 and the workpiece 4, hydrogen gas is generated on the electrode surface 2a, and an impact pressure is applied to the gap due to volume expansion due to this instantaneous gas generation. If the processing area S is small, even if gas is generated at the center of the processing surface 4a,
Pressure escapes to the surrounding area. Therefore, when the machining area S is small, even if larger electrical energy is supplied, the electrolyte in the gap will not be subjected to impact pressure due to gas generation, and the surface roughness of the workpiece surface can be improved in a short time. obtain.

However, when the processing area S is large, the flow path resistance in the gap due to the viscosity of the electrolyte is large, and instantaneous impact pressure due to gas generation is maintained in the gap, and this pressure causes the electrode 2 and the workpiece to The electrolyte between them moves rapidly, and the workpiece surface 4
The electrolyzed products generated in a are allowed to migrate. Therefore, if larger electrical energy is supplied, stable improvement in surface roughness of the processed surface 4a cannot be expected due to the influence of electrolytic products floating in the gap. However, if smaller electric energy is supplied as in the present invention, the floating state of the electrolytic products will be different between the convex portions and the concave portions of the uneven portion of the processed surface 4a, and the electrolytic products will be separated from the electrolytic products near the convex portions. The more the electrolyte is renewed (spraying the electrolyte from the jet nozzle 80), the greater the renewal effect will be in the vicinity of the convex part, and the current will selectively flow to that position, causing the electrolyte to flow around the convex part. As a result, the surface roughness of the processed surface 4a is improved.

In the above embodiments, the current density was explained in terms of peak current density, but it goes without saying that average current density may also be used. Also, this invention is not limited to the field of mold processing, but is applicable to silicon single crystals in semiconductor production. It is also suitable for finishing in fields where slight internal stress on the surface due to mechanical processing is a problem, such as finishing of gallium histobase materials and mirror finishing of aluminum disks in magnetic storage devices using single crystal diamond. It can be applied.

[Effects of the Invention] As explained in detail above, in the electrolytic finishing method and electrolytic finishing apparatus according to the present invention, pulsed pulses are supplied between the machining holes according to the machining area of the workpiece. By changing the electrical energy, the electrical energy per unit area is made smaller when the processing area is large than when processing a small area, so the surface roughness of the processed surface can be improved regardless of the size of the processing area. It is possible to easily obtain a high-quality processed surface such as a glossy surface, and it is possible to achieve quality improvement and mechanization in the field of mold processing, where labor saving has been slow.

[Brief explanation of the drawing]

Figure 1 is a front view of the electrolytic finishing apparatus of the present invention, Figure 2
The figure is a block diagram of the device, Figure 3 is a block diagram of the main parts,
FIG. 4 is a front view of the human-powered device, FIG. 5 is a schematic diagram of the electrolyte filtration device, FIG. 6 is a flowchart showing an example of finishing operation, and FIG. 7 is a diagram showing the display of the display device. 1... Electrolytic finishing processing device, 2... Electrode, 4...
Workpiece, 4a... Processing surface, 8... Power supply device, 9
...Motor drive control section, lO...Machining condition control section,
11... Electrolyte flow control section, 12... Control device, 13
...Input device, 14... Electrolyte filtration device, 46...
・CPU. Patent applicant: Shizuoka Seiki Co., Ltd. Representative Shigeo Suzuki Figure 1

Claims (3)

[Claims] (1) A finishing method using electrolytic machining, which includes the following steps: A. A step of supplying pulsed electrical energy between the opposing electrodes and the workpiece via a stationary electrolyte. B. Setting the processing area of the workpiece. C. Changing the electrical energy according to the size of the processing area, and setting the electrical energy per unit area to be smaller when the processing area is large than when the processing area is small. D. Eliminating electrolysis products generated between the electrodes. (2) In claim (1), the electric energy to be changed depending on the size of the processing area is 0.06 coulomb/cm.
A finishing method by electrolytic machining, characterized in that ^2 to 0.3 coulombs/cm^2. (3) An electrolytic finishing device having the following configuration. (b) Pulse supply means for supplying pulsed electrical energy between the poles of the workpiece and the electrode, which are placed opposite each other via a stationary electrolyte. B. Machining area setting means for setting the machining area of the workpiece. C. Control for controlling the pulse supply means such that the electrical energy is changed according to the size of the processing area, and the electrical energy per unit area is smaller when the processing area is large than when the processing area is small. means. D. Electrolytic product removal means for removing electrolytic products generated between the electrodes.