JPH048424A - Electrochemical machine and electrochemical machining device - Google Patents

Abstract

PURPOSE:To generate an electrochemical reaction equally in a process gap, and to set a process condition for obtaining a high accuracy process shape by setting the total current amount of pulse current in an electrochemical machining based on the surface roughness of a material to be processed before processing, and on an aimed surface roughness. CONSTITUTION:The setting of a process condition is started by a process condition control part 15 of a controller 12, and when a process area Ar of a work 1, a process gap value Gp, a surface roughness Rm0 before processing and an aimed surface roughness Rm1 are set, the amount of current application Ia per unit process area necessary for obtaining the aimed surface roughness Rm1 is calculated from the surface roughtness Rm0 before processing. A process depth Dp, or the amount of process enlargement is calculated, and the amount of total current application Iat necessary for electrochemical process is calculated, and an optimal pulse current waveform for equalizing the electrochemical reaction to the process area Ar of the work 1 as well as to the process gap value Gp, is determined. By applying the pulse current of the optimal peak current value Ip thus obtained, a rate of change of waveform Wf, and of a pulse width Tp, electrochemical process can be carried out without reaction variation.

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention has a method in which a tool electrode and a workpiece are opposed to each other with a set machining gap value, an electrolytic solution is interposed between the tool electrode and the workpiece, and a pulse current is supplied. The present invention relates to an electrolytic processing method and an electrolytic processing apparatus for processing the above-mentioned workpiece.

[Conventional technology]

Fig. 17 is a schematic configuration diagram showing a conventional electrolytic processing apparatus disclosed in, for example, Japanese Patent Application Laid-Open No. 1-216723, and Fig. 18 shows the shape of the machined surface of a workpiece machined by this electrolytic processing apparatus in the vertical direction. FIG. 3 is an exaggerated cross-sectional view. In the figure, (11 is the workpiece, (2) is the tool electrode, (
3) is a machining tank, (4) is an electrolytic machining liquid, (5) is a machining electrode drive means 1, such as a drive motor, and (6) is a drive motor (5).
) A drive mechanism that converts the rotational motion of the tool electrode (2) into vertical motion of the tool electrode (2), (7) a machining fluid supply device, (8) a solenoid valve for machining fluid supply, (9) a jet nozzle for machining fluid supply, (10)
(11) is an electrolytic current power source that supplies a pulse current between the tool electrode (2) and the workpiece (1), and (12) is the machining fluid jet hole in the tool electrode (2). A control device that controls the position relative to the workpiece (1), the magnitude and waveform of the supplied pulse current, the supply amount of the machining fluid (4), etc.
13) is an electrode position control unit that commands the drive motor (5) so that the machining gap value between the workpiece (1) and the tool electrode [2] becomes a predetermined value, and (14) is a machining fluid supply device (4). ), the machining fluid control unit (15) sets the peak current value, pulse width, and pulse period of the above-mentioned supplied pulse current, and outputs a command according to the set values to the electrolytic current power source (11). Details of the electrolytic current power supply flll and the machining condition control unit [15] will be described later. Note that (16) is the control device i! f12) is a large sword device that inputs setting values from the outside. FIG. 19 is a diagram showing details of the electrolytic current power supply +Ill and the processing condition control section (15). That is, the electrolytic current power supply +111 is composed of a DC power supply part (7o) and a charging/discharging part (71), and the DC power supply part (7o) is
The transformer (72) and the rectifier (73) are connected, and the transformer (
72), the voltage is lowered to a predetermined value, and the rectifier (73) rectifies the voltage to obtain a direct current, which is then connected to a capacitor [74-
11 to [74-n). In addition, the charging/discharging unit (71) is connected to a plurality of capacitors [74-11 to (74-n) and each of these capacitors +74-1) to (74-n) for discharging electric charge into the machining gap. , diodes 175-1) to (75-nl) to prevent reverse flow of charges to the DC power supply section (70) side, and discharge switches (76-11 to [75-nl) that are opened and closed to discharge charges to the discharge side.
6-n)', and each of the capacitors (74-11 to (74-n
), and a charging switch (77) for supplying and disconnecting power from the DC power supply section (70) to charge the battery to a predetermined value. The processing condition control unit (15) controls the capacitors f74-1) to
(A voltage detector (78) that detects the voltage value of 74-nl, and a voltage comparator that compares the voltage value detected by this voltage detector (78) with the output value from the D/A converter (79) (8
0), a charging detector (81) that detects the completion and start of charging of the capacitors [74-1) to (74-n) by the output signal from the voltage comparator (80), and a charging detector (81) that detects the completion and start of charging of the capacitors [74-1] to (74-n), a current detector (82) that detects the current value of the electric charge to be detected, a peak hold circuit (83) that holds the peak value of the current value detected by the current detector (82), and this peak hold circuit (83). A current comparator (85) that compares the peak current value held by the D/A converter (84) with the output value of the D/A converter (84), a pulse generator (86) that generates a pulse of a predetermined time width, and a pulse generator (86) that discharges into the machining gap. a gate circuit (88) that outputs an opening/closing drive signal to each of the discharge switches (76-11 to (76-n)) based on an input signal from a current waveform setting device (87) that sets the current waveform of the charge, and each of the capacitors. [A charging voltage setting device (89) that sets the charging voltage value to be supplied to 74-11 to (74-n) and outputs the signal to the D/A converter (79); a current setting device (90) that outputs the signal to the D/A converter (84);
4-n) a charge discharger (91) for discharging the residual charge;
A charge discharge command device (92) that outputs a control signal to the charge discharge device (91), a contact detector (93) that detects contact between the tool side 12) and the workpiece (1), and the human power device ( 1
It consists of a CPU [941, etc., which calculates and processes machining conditions, etc. based on the input data etc. of 6). In addition, the symbol (
95) is connected to each discharge switch (76-11) by the back electromotive force.
~f76-nl is a diode that prevents it from being destroyed. The conventional device is configured as described above, and its operation will be explained next. First, the drive motor (5) is operated according to the command value set in the electrode position control section (13) in the control device (12).
The position of the tool electrode (2) is controlled via the drive mechanism (6), and the tool electrode (2) is placed in the workpiece (11) in the processing tank (3).
and the set machining gap value. Thereafter, the machining fluid supply device (7) is activated by a command from the machining fluid control section (14) in the control device (12), and the machining fluid (4) is placed in the machining tank (3).
) is satisfied, the control device (12) as in the operation described below.
In response to commands from the machining condition control unit (15) inside, pulsed electric current with a predetermined width and a predetermined peak value is supplied from the electrolytic current power source (11) between the tool electrode (2) and the workpiece m at a predetermined period. Intermittent electrolytic action occurs in the machining gap between these picture electrodes (1) [21]. That is, the operation of the electrolytic current power source (ill) and the machining condition control section (15) shown in FIG. 19 above is explained as follows using the flowchart shown in FIG. Fix it in a predetermined position and turn on the power [1001] Then, for example, when you press the discharge key (not shown) of the human power device (16), the 2 above-mentioned discharge switches (76-1) to (76-n) are turned on. At the same time, the charge discharge command device (92) to the charge discharger (91
), and this signal turns off the charge discharger (91) that was turned on in the step (1001) (101). When the charge discharger (91) turns off, this charge discharger (91) turns off.
1) Time Tl~ during which a predetermined current can flow through the resistor constituting
Read Tn from CP LJ (94) (1021,
As shown in FIG. 21(A), Tl to Tn is the time required to keep the average power consumption of the resistor constant when discharging through the resistor of the upper charge discharger (91). T.I.
is the time that can flow at the maximum charging voltage of the capacitors (74-1) to f74-n) (area SL in Fig. 21 = time corresponding to the electric power), and ■2 to Tn are the same area 82 as the area SL of TI ~Sn is obtained. In addition, this time TI
-Tn is determined in advance from the discharge characteristics of the capacitance C of the capacitors (74-11 to (74-nl) and the resistance value R of the resistor of the charge discharger (91)) and is stored in the CPU (94). Then, based on the above TI-Tn, a predetermined period T, for example, a long Ts waiting time required to discharge a predetermined voltage Vs, which will be described later, is calculated (103).
From the characteristics shown in l, voltages v1 to l/n corresponding to (1) to Tn, which are stored in advance in the same way as Tl-Tn above, are read (104). When the voltage Vl=Vn is read, the processing condition control section (15)
The control signal causes the voltage detector (78) to turn on the capacitor (
The voltage v, (residual charge) of 75-11 to (75-n) is detected ffl (1051), and it is determined whether this voltage Vo is less than or equal to the predetermined value Vs (1061). In this determination (106), N
In the case of O, that is, the capacitors (74-1) to (74-n)
(7) If voltage v0 exceeds Vs, step f10
From v1 to Vn read in step 41, a voltage Vi immediately above Vo and a time Ti corresponding to this voltage 1 are selected (107). Then, the Ti time charge is discharged (10
8) After waiting time (109) of L, T-Ti time. Return to step (105) and repeat until YES in step (1061).In other words, the voltage Va of the capacitors (74-1) to (74-n)
is controlled by the charge discharge command device (
92) causes the charge discharger (91) to discharge Ti11. Ti÷2... The residual charge is discharged by sequentially turning on the time. Note that the discharge switches (76-11 to f76-n) remain in the on state. The above step (YES in 1061, that is, the capacitor +74
-11~f74-n) voltage Va becomes below Vs,
A preset fixed time 1, for example, a time Ts longer than the above-mentioned time Tl-Tn Heavy charge discharge (1101L) At the same time as finishing discharging the residual charge, the charge discharger (91) is activated by the control signal of the charge discharge command unit (92). In this series of steps, the capacitors (74-1) to (74-n) that remained before the start of processing (remained at the end of the previous processing)
When the discharge of the residual charge is completed and the residual charge disappears, machining is started in this state, and first the electrode (2) descends and comes into contact with the workpiece (1). This contact is detected by the contact detector (
93) detects fl121, the CPtJ (94) stores this point as the machining origin A, and operates the machining fluid supply device (7) to supply electrolyte into the machining tank (3) (113). do. Then, the electrode (2) is raised and set at a position that maintains the machining gap input using the input device (16) (fl14). Electrode (2) is set and the electrolyte in the machining gap is stationary [115
), the control signal from the machining condition control section (15)
Capacitors f75-1) to (75-) of electrolytic current power source (11)
A predetermined pulse current corresponding to the processing area S of the workpiece (11) is supplied from nl (116) L, and after this pulse current is turned off, the electrode (2) is raised [117]. Then, the machining fluid supply device M(7) causes the jet nozzle (
9) Or, fresh electrolyte is ejected from the injection hole (lO) into the machining gap, and the electrolytic products eluted from the machining gap are removed by supplying a pulsed current fl18). Thereafter, the electrode (2) is lowered +119) to make contact with the workpiece surface, and this position is compared with the origin A using the CPU (94+) to measure the machining depth (120). Step (114)~ until the predetermined value is reached.
+1201 is repeated (121), and when the predetermined machining depth is reached, the control signal from the machining condition control section (15)
Switch the pulse current supplied from the capacitors +74-11 to (74-n) to a predetermined pulse current (122), and perform the same processing as in steps +1141 to (1181) (12
3) to f127) are repeated a predetermined number of times (128), a glossy surface is obtained and all processing is completed f129>. As described above, the pulse current during processing is always controlled by the processing condition control section (15) and the electrolytic current power source (11) so that the current density in the processing gap is always a predetermined value. The workpiece (1
) The machined surface shape (8) shown exaggerated in the vertical direction is the first
As shown in FIG. 8, the vicinity of the inner and outer peripheral portions of the tool electrode (2) becomes over-machined, resulting in an abnormally machined shape. This is because even though the machining fluid (4) in the machining gap is stationary during electrolytic action, the machining fluid (4) flows around the inner and outer peripheries of these tool electrodes (2) due to thermal convection, electrolytic bubbles, etc. This is because a larger amount is given, causing uneven electrolytic action. [Problem B to be solved by the invention] The conventional electrolytic machining apparatus is configured as described above, and the current density in the machining gap during machining is only controlled to a predetermined value. There is a problem in that it is not possible to properly deal with the uneven reaction of electrolytic action that occurs in the machining gap, resulting in abnormally machined parts. In addition, a predetermined machining depth is set in order to obtain a predetermined surface roughness, and this machining depth is calculated by accumulating the machining depth measurement value for each pulse current supply, and the machining is performed until it reaches the set value. Therefore, in order to obtain accurate surface roughness, it is necessary to set the machining amount based on experience and repeated data.
Measuring the machining depth also cannot be accurate because it is measured when electrolytic products are mixed in the machining fluid or adhered to the tool electrode or the workpiece. Due to this measurement error, a predetermined machining depth cannot be obtained, leading to excessive machining and a high possibility of producing defective products. This invention was made to solve the above-mentioned problems, and it is possible to make the electrolytic reaction occurring in the machining gap uniform, and also to set the machining conditions to obtain a highly accurate machined shape. The purpose is to obtain a processing method and electrolytic processing equipment. Furthermore, another object of the present invention is to obtain an electrolytic machining method and an electrolytic machining apparatus that can accurately obtain a target machined surface roughness and can also accurately process dimensions. [Means for Solving the Problem] The electrolytic machining method according to the present invention interposes an electrolytic solution between a tool electrode and a workpiece, supplies a pulsed current, and adjusts the total current amount of the pulsed current to the workpiece. This method is characterized in that it is set based on the surface roughness of the workpiece before machining and the target surface roughness. Further, in the electrolytic machining method according to another aspect of the present invention, an electrolytic solution is interposed between a tool electrode and a workpiece, and a pulsed current is supplied, and the total amount of the pulsed current is used to process the workpiece. In addition to setting from the previous surface roughness and target surface roughness,
The pulse current is divided into divided pulse currents to obtain the total amount of current. Further, the electrolytic machining apparatus according to the present invention provides pulses based on a predetermined relationship based on the machining gap value between the tool electrode and the workpiece set by the electrolytic position control section and the machining area manually inputted to the control device. The apparatus is equipped with an optimum pulse current calculation means that calculates the optimum peak current value and the optimum waveform change rate of the current, and sets the calculated values as the supply pulse current value. Further, an electrolytic machining apparatus according to another aspect of the present invention is configured to calculate an applied current amount per unit machining area from the surface roughness before machining and the target surface roughness of the workpiece that are input to the control device. an applied current amount calculation means, an applied total current calculation means for calculating the total amount of applied current from the calculation result of this means and the machining area of the workpiece inputted to the control device, a calculation result of this means and a set peak current value; total number of applied pulses calculating means for calculating the total number of applied pulses from the pulse width and pulse width, and machining time calculating means for calculating the machining time from the calculation result of this means and the set reference pause time between applied pulses. A machining stop means that outputs a machining stop command according to the calculation result of this means, a machining expansion allowance calculation means that calculates a machining expansion allowance from the calculation result of the above-mentioned applied current amount calculation means, and this means and the above-mentioned machining time. and display means for displaying the calculation results of the calculation means on a display device. Further, an electrolytic machining apparatus according to another aspect of the present invention interposes an electrolytic solution between a tool electrode and a workpiece, supplies a pulsed current, and sets the peak current value and waveform shape of the pulsed current to a set value. It is equipped with an adjusting means for adjusting. Furthermore, an electrolytic processing apparatus according to another invention of the present invention includes:
In addition to the intermittent machining fluid supply route that intermittently supplies a large amount of machining fluid for removing electrolytic products, a machining fluid constant supply route is provided that constantly supplies a small amount of machining fluid during electrolytic machining. [Operation] The electrolytic machining method according to the present invention performs machining by setting the total amount of pulsed current supplied between the tool electrode and the workpiece based on the surface roughness of the workpiece before machining and the target surface roughness. Eliminate electrolysis products remaining in the gap. Further, in the electrolytic machining method according to another aspect of the present invention, the pulse current to be supplied between the tool electrode and the workpiece is set based on the surface roughness of the workpiece before machining and the target surface roughness. The pulsed current is divided into pulsed currents to obtain the total amount of current, and the workpiece is precisely machined while eliminating electrolytic products remaining in the machining gap. In electrolytic machining, the electrolytic reaction in the machining gap is The components of the machining fluid and the amount of the machining fluid that exist between the two electrodes.In other words, they depend on the machining gap value, machining area, peak current value, and waveform change rate.Therefore, in the electrolytic machining apparatus of the present invention, the amount of machining fluid If the relationship between the optimum peak current value and waveform change rate that makes the electrolytic reaction uniform with respect to the components, machining gap value, and machining area is determined in advance through experiments, and the machining gap value and machining area are set externally, The optimal peak current value and waveform change rate are calculated from the above predetermined relationship, and the electrolytic current with the optimal pulse waveform is supplied, and the electrolytic reaction is performed uniformly, resulting in a highly accurate processed shape with no reaction unevenness. In addition, in electrolytic machining, the amount of machining that is approximately comparable to the amount of pulse current applied per unit area of machining is obtained, and the surface roughness of the electrolytically machined surface becomes finer in proportion to this amount of machining. Therefore, in the electrolytic processing apparatus according to another aspect of the present invention, the amount of applied current per unit processing area required to obtain a predetermined target surface roughness from the surface roughness before each processing is calculated. The relationship is determined in advance through experimentation, and the amount of current applied per required unit machining area is calculated based on the above predetermined relationship from the surface roughness before machining of the workpiece and the target surface roughness input from the outside. The total amount of current to be applied is calculated from this calculated value and the machining area of the workpiece input from the outside, and the total amount of current to be applied is calculated from this total amount of current and the peak current value and pulse width of the set pulse current. The number of pulses is calculated, and the machining time is calculated from this total number of applied pulses and the set reference pause time between applied pulses.This machining time is used to stop automatic electrolytic machining.Then, this machining time and The machining expansion amount calculated from the applied current amount per unit machining area is displayed before machining starts.Furthermore, an electrolytic machining apparatus according to another aspect of the present invention includes:
An adjusting means that adjusts the peak current value and waveform shape of the pulse current supplied between the tool electrode and the workpiece to a set value acts to uniformize the electrolytic reaction, thereby precisely machining the workpiece. Further, in another aspect of the present invention, a large amount of machining fluid of 0-II2/sin or more per 1 cm of machining area is intermittently applied to the machining gap between the tool electrode and the workpiece during the pause time when no pulse current is supplied. When pulsed current is supplied, the electrolytic products are removed, and when pulsed current is supplied, 0.0.
A minute amount of machining fluid of 05I2/sin or less is supplied, and a gentle flow of machining fluid is generated in the machining gap during the electrolytic action, making the electrolytic action uniform and eliminating the abnormal machining state. [Examples] Examples of the present invention will be described below with reference to the drawings. Fig. 1 is a schematic configuration diagram showing a control device in an embodiment of the present invention, Fig. 2 is a circuit diagram showing a basic circuit for applying pulsed current in electrolytic processing, and Fig. 3 is a waveform of applied pulsed current in this embodiment. Figure 4 is a relationship diagram showing the optimum peak current value and optimum waveform change rate for the machining area and machining gap value, and Figure 5 is the applied current per unit machining area necessary to obtain the required target surface roughness. Fig. 6 is a relational diagram showing the amount of applied current per unit processing area and processing depth, Fig. 7 is a flowchart showing the operation of this embodiment, and Fig. 8 is a diagram showing the processing depth according to this embodiment. FIG. 3 is a cross-sectional view showing the shape of the machined surface of the workpiece in an exaggerated manner in the vertical direction. Note that FIG. 17 can also be used in this embodiment. In the figure, (12) is a control device including a microcomputer (hereinafter referred to as microcomputer), (17) is a display device, (18) is a machining gap value Gp (μm) set by electrode position control (13), From the machining area Ar (cm") input from the input device (16), the optimal peak current value IpfA) and the optimal waveform change rate of the supply pulse current shown in FIG. 3 are determined based on the predetermined relationship shown in FIG. 4. W f
(Optimal pulse current calculation means that calculates A/m5ecJ, sets it, and outputs it. (19) is the surface roughness RIll of the workpiece (1) before machining inputted from the input device (16).
. (From μml and the target surface roughness RIII (μm) after machining, calculate the amount of applied current Ia (A-sec/cm”) per unit machining area according to the predetermined relationship shown in Figure 5. The applied current amount calculating means (2o) is the applied current amount Ia (^・sec/clI+2) per unit processing area inputted from this means (19) and the input device (1
(21) is a total applied current amount calculating means for calculating the total applied current amount fat (A-sec) from the machining area A r 1eI11") input from 6); (21) is the applied current amount input from this means (20) The total current amount fat [A-sec], the pulse peak current value Ip (A>) manually input from the optimum pulse current calculation means (18), and the pulse waveform change rate Wf (^/m
5ec) and the pulse width Tp (s+5ecl), the total number of applied pulses calculation means (22) calculates the total number of applied pulses pt input from this means (21) and the memory (23) in advance. A machining time calculation means (24) calculates the machining time T + a (sec) from the reference rest time TO (m5ec) between applied pulses set and stored in the machine; (24) measures the elapsed time from the start of machining; When the time reaches the machining time TII (SeC) input from the means (22), the electrolytic current power source (11
1 and a machining stop means that outputs a machining stop command to the machining fluid supply device (7), (25) is the applied current amount per unit machining area Ia (^・A machining expansion calculation means (26) calculates the machining depth Dp (μm), that is, the machining expansion allowance, according to the predetermined relationship shown in FIG. machining enlargement allowance Dp (μlI) from and machining time T input from machining time calculation means (22)
m (see) on the display device (17). In addition, the optimum pulse current calculation means (18), the applied current amount calculation means per unit area (19), the total applied current amount calculation means (20), the total applied pulse number calculation means (21), the machining time calculation means (22) , memory (23), processing stop means (2
4), processing enlargement calculation means (25), display device (26)
This constitutes a control device (15). Note that the other parts are the same as those shown in FIG. 17, and their explanation will be omitted. Next, the operation will be explained according to the flowchart shown in FIG. First, prior to machining, setting of machining conditions is started in the machining condition control unit (15) of the control device (12) (step (Sl)), and in step (S2), the machining conditions are set (step (S1)).
) is set, and the step (S
3), the machining gap value Gp is determined by the relationship shown in the curve Gp in Figure 4.
(μm) is set (FIG. 4 will be described later), and in step (S4), the surface roughness before machining Rm, (μre) and the target surface roughness RI1. (uIll) are the input devices (16
) is set by the operator. Next, step (S
In 5), the surface roughness Ra before processing is determined according to the relationship shown in FIG. (Amount of applied current 1a (A-sec/c+a) per unit processing area necessary to obtain target surface roughness Ra+ (μm) from μml
”) is calculated. That is, the curves A, B, and C in FIG.
The vertical axis coordinate value at the left end of each is the surface roughness Rma before processing,
The vertical axis coordinate value at the right end is the target surface roughness Rm+, and the length between the left end and the right end on the horizontal axis represents the applied current amount Ia per unit processing area necessary to obtain the target surface roughness Rm1, and the curve A is the surface roughness Rm before processing. is large, B is medium, and C is small. The relationship shown in FIG. 5 has been determined from experimental results, and the data has been input into the microcomputer of the control device (12) in advance. Applied current amount per unit processing area 1a (A-sec/cm
”), the machining depth Dp (μm), that is, the machining expansion allowance, is calculated from this data in step (S6) according to the relationship shown in Figure 6. Figure 6 shows the applied current per unit machining area. This is a relationship diagram showing the machining depth Dp (u■) processed by the amount 1a (A-sec/cm"), which is also obtained from experimental results, and these data are stored in the control device (12).
is pre-entered into the microcontroller. As a result, the machining amount required to obtain the target surface roughness, that is, the machining expansion allowance is calculated, and in step (S7), this machining expansion allowance is calculated by the control device (
12) is displayed on a display device (17) such as a CRT attached to the computer. By determining this machining expansion allowance, the final machining shape of the workpiece [1] can be determined. Next, in step (S8), the applied current amount Ia (A-sec/cm"l) per unit processing area calculated in step (S5)
The total applied current amount fat (A-sec) required for electrolytic machining is calculated by multiplying by the machining area Ar (c++1'') of the workpiece (1) set in step (S2), and then In (S9) to (S151), the machining area A of the workpiece (1) set in step (S2)
r [cm") and the machining gap value G p (u ml) set in step (S3), the optimum pulse current waveform that makes the electrolytic reaction uniform is determined. First, step (
In S9), the pulse width T p (m5ec) is calculated,
The machining gap value Gp (μ+
It is determined whether a) is a predetermined standard machining gap value for the set machining area Ar (cn+''), and steps [3101 to (Sll) or step +513 are performed accordingly]
) to (S15), the optimum peak current value Ip (A) and the optimum waveform rate W f (A/m5e
c) is selected. In Fig. 4, the curve Gp is the machining gap value G with respect to the machining area A r (cm”) (horizontal axis).
p(u■) (vertical axis), and normally the machining gap value Gp is set so that it lies on the reference line, but if it is not possible to set the machining gap value to the standard machining gap value due to the relationship with other machining, , respectively, are set to machining gap values that are translated vertically. Curve I
p is the optimum peak current value Ip (Al (horizontal axis) for the set machining gap value Gp (LLml (vertical axis)), and the curve Wf
respectively indicate the optimum waveform change rate W f (A/m5ec) (horizontal axis) with respect to the set machining gap value Gp (μm) (vertical axis). For example, if the set machining area is Ar+ and the standard machining gap value Gpl is set, the abscissa value p of the intersection of the horizontal line passing through this point and the curve Ip is the optimal peak current value Ip (A). , the abscissa value Wf of the intersection with the curve Wf is the optimal waveform change rate W f (A/w
sec), and these are selected in step (Sll) and step (S12). In addition, the standard machining gap value G
If the machining gap value Gpz cannot be set to p+ and is set to a smaller machining gap value Gpz, the amount of difference from the standard machining gap value Gp+ is detected in step (s+3), and the horizontal line and curve are shifted downward by that amount. ! The abscissa value Ipt of the intersection with p is the optimum peak current value Ip(A), and the abscissa value Wf of the intersection with the curve Wf is the optimum waveform change rate Wff^/-5ec), and these are the optimum peak current value Ip(A) and the abscissa value Wf of the intersection with the curve Wf is the optimum waveform change rate Wff^/-5ec). Step (S15
1 is selected. The relationship shown in Figure 4 was also obtained from the experimental results, and these data are used by the control device! ! (12) is input into the microcomputer in advance. In this way, the pulse width Tp (msee), peak current value Ip fA) and waveform change rate Wf (A/m5) of the l pulse shown in FIG.
ec) is determined, in step fs16), the waveform area of one pulse, that is, the current amount of one pulse Iap(^・5ec)
is calculated, and in step (S17), step (
The total applied current amount I ap (A-sec
) by the current amount Iap (A-sec) of one pulse calculated in step (516), the total number of pulses pt to be applied is calculated, and the total number of pulses pt to be applied is calculated in advance in the memory (23) in step (S18). The stored reference pause time T o (msec) between applied pulses is set, and in step (S19), the pulse width Tp (msec) set in step (S9) and the pulse width Tp (msec) set in step (SIIS) are set. By multiplying the sum of the reference rest time T o (a+5ec) by the total number of pulses pt calculated in step fs17), the total pulse application time, that is, the machining time T+
m(see) is calculated. This machining time Tm is displayed on the display device (1
7) is displayed on a CRT, etc. The setting of the machining conditions is completed above, and the machining operation is started in step (321), and the machining operation is performed in step [522]. This machining operation is similar to the conventional example described above, so a detailed explanation will be omitted, but the pulse width Tp (msec), peak current value Ip (A), and waveform change rate W f ( The basic electric circuit when performing electrolytic processing using the pulse current waveform shown in Figure 3 of A/m5ec) is shown in Figure 2, and the pulse width TI)
(msec) is the on/off timing of the transistor TR, the peak current value Ip [^) is the magnitude of the applied voltage V, and the waveform change rate W f [A/m5ec) is the peak current value Ip, pulse width Tp, and capacitor capacitance C determined by Therefore, a predetermined waveform change rate 1 for each value of peak current value Ip and pulse width Tp that can be set by experiment etc.
The value of the capacitor capacitance C to obtain 1f is determined in advance, and this is stored in the memory in the microcomputer of the control device M (12), and the peak current value p and pulse width Tp of the selected pulse current are calculated. The capacitor capacity tc may be changed to a value determined in advance for the waveform change rate Wf. When the time from the start of machining reaches the machining time Tm calculated in step fs19), step [5231
Proceeding to step S241, the application of the pulse current and the supply of the machining fluid are stopped, and the electrolytic machining is completed. As described above, in this embodiment, the optimal peak current value IpiA!, the waveform change rate Wf ) and pulse width T p (msecl), electrolytic machining with no uneven reaction as shown in FIG. Therefore, even if the current density is the same, the peak current value of the Barsum flow is 1.
pf^), and the waveform change rate Wf (^/5sec), as shown in Fig. 18, an abnormal machined part may occur due to the difference in electrolytic reaction, making it impossible to obtain a highly accurate machined shape. By simply inputting the previous surface roughness, target surface roughness, and machining area, you can know the machining time and machining allowance to obtain the target surface roughness before machining, and once the target surface roughness has been machined, the electrolytic Machining can be stopped automatically. In the above example, the machining gap value was set separately from the machining area, but if it were possible to set the standard machining gap value, you could just set the machining area and from now on, the standard machining gap value would be set. In addition, in the above embodiment, so-called static electrolytic finishing processing in which processing is performed while the processing fluid in the processing gap is stationary has been described, but other electrolytic processing machines that perform processing using a pulsed current waveform may be used. The object of the present invention can be achieved if similar machining data is obtained.Furthermore, Fig. 9 is a diagram for explaining another embodiment of the present invention. The schematic configuration of the main parts is shown, and the processing condition control section (1) of the device configuration diagram shown in FIG.
This corresponds to 5). The other parts are the same as in Fig. 17.
The explanation will be omitted. In FIG. 9, (5G) is a shunt that shunts and outputs the electrolytic processing current, (51) is a comparator that compares the output of the shunt (50) with a reference current detection level and outputs a signal. (52) is an AND circuit that outputs a normal signal or an abnormal signal by the AND signal of the output of the comparator (51) and the clock signal, and (53) is the comparator (
51) is a rising differentiation circuit that differentiates the rising edge of the output signal, (54) is a NOT element, and (55) is a flip-flop that performs a predetermined operation based on the output signals of the rising differentiation circuit (53) and NOT element (54). It is something to do. or,
(56) is an AND circuit that operates a transistor (not shown) of the electrolytic current power source (11) based on an AND signal of the clock signal and the signal of the flip-flop (55). The embodiment device of this invention is configured as described above,
Next, an embodiment method of the present invention using the above-mentioned embodiment apparatus will be explained. First, as explained in FIG. 4 of the above embodiment, using a machining condition setting table in which various machining conditions determined experimentally are set, from the surface roughness before machining and the target surface roughness of the workpiece, Set the total amount of pulse current required to electrolytically process the workpiece. In addition, in this embodiment method, the current density to the workpiece is set to 30A/cm or more.Next, the peak current value and pulse width of the pulse current are set, but the inventor conducted many experiments. From the results, it was found that the pulse width has a large influence on achieving high-speed machining while ensuring the specified surface roughness of the workpiece under the set peak current value. Pulse width is also the first
10m5ec~50IIIS as shown in Figure 0 (a>
It has been found that values in the range of eC are optimal. Based on experimental results (examination), it was found that this was due to the following reasons. Namely, as explained in the prior art, one pulse was applied between the tool electrode (2) and the workpiece (11). The electrolytic current If the pulse width of is less than 10m5ec, the workpiece [1]
Processed electrolytic products adhere to the surface of the machine, causing a decrease in processing speed. In addition, when the pulse width of the electrolytic current exceeds 50 seconds, the set peak current becomes rounded and a so-called "sagging" phenomenon occurs, as illustrated in Figure 11. The processing speed decreases because the pulse current waveform is deformed and the desired shape cannot be obtained. Next, electrolytic machining is performed using the above method to obtain the desired machining accuracy, but in machining that places even greater emphasis on accuracy, two
Process by the following method. That is, as shown in FIG. 10(b), the above-mentioned 10m5e
The pulse width set to c~50m5ec is divided into 3 to 15 parts, a pause time of 5 to 20 times the divided pulse width Ps obtained by one division is provided, and the pulse current obtained in this way is continuously applied and the The workpiece (1) is electrolytically processed. The important thing here is that the above 10m5ec~50sse
The pulse width of one pulse current set to c should be equal to the sum of the pulse widths Ps of the divided pulse currents, that is, the same amount of pulse widths should be obtained. When electrolytic machining is performed using a pulse current having a divided pulse width Ps as described above, machining with improved machining accuracy can be obtained without reducing the machining speed of the workpiece (1). Next, input the machining conditions for electrolytic machining using the input device (
When machining is started by setting 16) and electrolytic machining is progressed, the peak current value of the pulse current changes according to the machining state, so the current density changes as shown in FIG. This current density is determined by detecting the electrolytic current using a shunt (50) and comparing it with the current detection level using a comparator (51) as shown in Figure 9. is being determined. In other words, when the electrolytic current density is continuously lower than 3OA/cm, it is considered an abnormal condition and the supply of pulse current is stopped and the machining is stopped.Also, when setting the machining conditions, the electrolytic current density is set to 30^ / If the pulse current changes temporarily during machining and the peak current value falls below the current detection level, the rising differential circuit (53) shown in Figure 9 operates and detects an abnormality. A signal is output to cut off the portion where the peak current value of the pulse current waveform falls below the current detection level.The operation time chart at this time is shown in Figure 13.Next, the pulse current is set during machining. If it falls below the value,
Depending on the cause, it is necessary to return the pulse current to an appropriate level. FIG. 14 shows a method for properly returning this pulse current. In order to return this pulse current appropriately, the experimentally determined data shown in FIG. 15 is used. For example, if a phenomenon in which a part of the pulse current waveform decreases occurs, it is clear from the experimental data in FIG. 15 that this is a phenomenon that occurs when the applied voltage is high and the machining gap is narrow. Therefore, the operation of the rising differential circuit (53) in Figure σ cuts off the portion of the peak current value that has fallen below the current detection level, but if the pulse current waveform is not normalized thereafter, adjustment is made to lower the applied voltage. Alternatively, a signal is sent to the electrode position control unit (13) to widen the machining gap to widen the machining gap.Also, if the peak current value of the pulse current waveform is not secured from the beginning of machining, the input device (16) It is possible that the electrode position data input from the machine is incorrect, or that the electrolytically processed product remains in the machining gap.In the former case, it is a setting error and the problem can be resolved by changing the settings.In the latter case, the problem can be solved by changing the settings. In order to increase the jetting pressure of the machining fluid higher than the set value (and remove the electrolytic products in the machining gap), or as shown in Fig. 15, the peak current value increases as the machining gap is narrowed, so The output signal of the AND circuit (52) shown in the figure is sent to the electrode position control section (13), and the electrode position is corrected to match the detected peak current value.That is, the machining gap is narrowed to normalize the peak current value. Next, as another method for normalizing the peak current value, as is clear from Fig. 15, the applied voltage may be increased.
Next, this method will be explained. If the voltage is high and the machining gap is narrow in the pulse current waveform shown in FIG. 15, the standard pulse current waveform shown in FIG. 3 will not be obtained. This occurs when the electrolytic products generated by one pulse current exceed the allowable amount of electrolytic action possible in this narrow machining gap, so as mentioned above, the part of the pulse current waveform Temporarily shuts off. In addition, electrolytic products generated in the machining gap as machining progresses are removed from the machining fluid supply bag W (7) each time machining is carried out.
), but if an abnormality in the pulse current is detected due to residual electrolyte, etc., the machining fluid control unit (14)
Adjust the set machining fluid jet pressure with . Furthermore, when the machining area is input as an external factor from the input device (16), the machining fluid ejection pressure, that is, the machining fluid amount corresponding to the machining area is set. FIG. 16 shows another embodiment of the present invention. In the figure, (6o) is a jet nozzle (9) and a jet port (lO
), c61) is the adjustment valve, (62) is the flow meter, and (63) is the machining fluid supply device (7).
) is a machining fluid constant supply path that extends from the adjustment valve (61) and flow meter (62) to the jet nozzle (9) and jet port (10). Note that the other parts are the same as those shown in FIG. 17, and their explanation will be omitted. Next, the operation will be explained. The control device (12) is placed so that the tool electrode (2) and the workpiece [1] face each other in the processing tank (3).
The drive motor (5) is operated according to the set command value of the electrode position control unit (13), and the position of the tool electrode (2) is controlled via the drive mechanism (6), and the position of the tool electrode (2) is controlled between the workpiece (1) and the Facing with the set machining gap value. Next, the machining fluid supply device (7) is
is activated and the machining tank (3) is filled with the machining fluid (4), the adjustment valve (61) is controlled so that the flow meter (62) reaches a predetermined set amount, and the machining fluid intermittent supply path is controlled. (60)
The machining fluid (4) is supplied to the jet nozzle (9) and the spout (10) through the machining gap, and a minute flow of machining fluid [4] of less than 0.05 I2/+sin per 1 cm of machining area is generated in the machining gap. Thereafter, according to a command from the machining condition control unit (15) of the control device (12), electrolytic galvanic current!
It is supplied to the machining gap between the tool electrode (2) and the workpiece (1), and electrolytic machining is started. During the pause time between the pulse currents, the solenoid valve (8) is opened for a short time and then closed by a command from the machining fluid control section (14), and the machining fluid is then passed through the intermittent supply path (60). A large amount of machining fluid (4) is supplied to the spout nozzle (9) and spout (10), and a large amount of machining fluid (4) is intermittently spouted into the machining gap, causing electrolysis to occur in the machining gap. Electrolysis products are removed. In this way, by causing a small amount of machining fluid to convect in the machining gap when pulsed current is supplied, the amount of machining fluid necessary for electrolysis is generated throughout the machining part, and the tool electrode (2) is heated during static fluid electrolysis.
Thermal convection caused by electrolytic action and liquid convection caused by electrolytic bubble convection occur uniformly throughout the machining gap near the inner and outer peripheries. As a result, an abnormally machined portion where a portion is over-machined does not occur, and the machined shape of the workpiece (1) becomes uniform as shown in FIG. 8. Note that the machining fluid supply device (7) has a filtration function, a machining fluid circulation function, a machining fluid jetting function, and a jet suction function, although their illustrations are omitted for the sake of explanation. [Effects of the Invention] As described above, according to the electrolytic machining method of the present invention, the total amount of pulse current supplied to the machining gap between the tool electrode and the workpiece is By setting the surface roughness and the target surface roughness, it is possible to eliminate electrolytic products remaining in the machining gap, and therefore, it is possible to increase the machining speed. According to the electrolytic machining method, the total amount of pulse current supplied between the tool electrode and the workpiece is set based on the surface roughness of the workpiece before machining and the target surface roughness, and Since the current is a divided pulse current that obtains the total amount of current, it is possible to eliminate electrolytic products remaining in the machining gap, increase the machining speed, and improve the machining accuracy of the workpiece. Further, according to the electrolytic machining apparatus of the present invention, the optimal peak of the pulse current can be determined based on a predetermined relationship from the machining gap value set by the electrode position control unit and the machining area input to the control device. We have provided an optimal pulse current calculation means that calculates the current value and the optimal waveform change rate and sets this calculated value as the supply pulse current value, so you can achieve uniform response without unevenness without having to set complicated processing conditions before processing. There is an effect that electrolytic machining can be performed with a highly accurate machined shape.Furthermore, an electrolytic machining apparatus according to another invention of the present invention has the following features:
Applied current amount calculation means per unit machining area that calculates the amount of applied current per unit machining area from the surface roughness before machining and target surface roughness of the workpiece that are input to the control device, the calculation results of this means and the control device An applied total flow rate calculation means for calculating the total amount of applied current from the machining area of the workpiece inputted to the processing area, and a total number of applied pulses is calculated from the calculation result of this means and the peak current value and pulse width of the set pulse current. A total number of applied pulses calculation means to calculate, a machining time calculation means to calculate the machining time from the calculation result of this means and a set standard rest time between applied pulses, and output a machining stop command according to the calculation result of this means. a machining stop means for calculating a machining expansion amount from the calculation result of the milling current amount per unit machining area calculation means, and a machining expansion amount calculation means for calculating a machining expansion amount from the calculation result of the said unit machining area per milling current amount calculation means, and the calculation results of this means and said machining time calculation means are displayed on a display device, respectively. Since the display device is equipped with a display means to display the surface roughness of the workpiece before machining, just inputting the surface roughness before machining, the target surface roughness, and the machining area, the display device shows the machining time and the machining area to obtain the target surface roughness before machining. The machining allowance can be known before machining, and these are automatically set, so that even an inexperienced person can easily perform electrolytic machining to obtain a desired surface roughness with an even finish. Furthermore, according to the electrolytic machining apparatus according to another aspect of the present invention, by providing an adjusting means for adjusting the peak current value and waveform shape of the pulse current supplied between the tool electrode and the workpiece to set values, It has the effect of making the electrolytic reaction uniform during electrolytic processing and improving the processing accuracy of the workpiece. Furthermore, according to the electrolytic processing apparatus according to another aspect of the present invention, in addition to the machining fluid intermittent supply path that intermittently supplies a large amount of machining fluid for removing electrolytic products, a trace amount of machining fluid is supplied during electrolytic machining. By providing a continuous supply path for machining fluid, the electrolytic action is uniform, and an electrolytic machining device capable of electrolytic machining into a uniform, high-precision machining shape without abnormal machining conditions can be obtained at a low cost. be.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram showing a control device in an embodiment of the present invention, Fig. 2 is a circuit diagram showing a basic circuit for applying pulsed current in electrolytic processing, and Fig. 3 is a waveform of applied pulsed current in this embodiment. Figure 4 is a relationship diagram showing the optimum peak current value and optimum waveform change rate for the machining area and machining gap, and Figure 5 is the amount of applied current per unit machining area necessary to obtain the required target surface roughness. A relationship diagram showing
Fig. 6 is a relationship diagram showing the machining depth with respect to the amount of current applied per unit machining area, Fig. 7 is a flowchart showing the operation of this embodiment, and Fig. 8 is the machined surface of the workpiece machined by this embodiment. A cross-sectional view showing the shape exaggerated in the vertical direction,
FIG. 9 is a schematic diagram of the main parts of the machining condition control section of an electrolytic processing apparatus showing another embodiment of the present invention, FIG. 1O is a diagram showing the pulse current used in this embodiment, and FIG. A diagram showing a pulse current waveform to explain the effect of the electrolytic machining method showing an example, FIG. 12 is a diagram showing the relationship between peak current and machining area for optimizing current density, and FIG. Figure 14 is a diagram showing the operation time chart of the electrolytic machining apparatus showing the example, Figure 14 is a diagram showing the factors controlled as the pulse current changes, and Figure 15 is an experimental diagram of the pulse current waveform that changes as the electrolytic machining progresses. The obtained diagrams, FIG. 16, is a schematic configuration diagram showing still another embodiment of the present invention, FIG. 17 is a schematic configuration diagram showing an example of the present invention and a conventional electrolytic processing apparatus, and FIG. 18 is a conventional electrolytic processing apparatus. 19 is a block diagram showing the main parts of the conventional device, and FIG. 20 is a cross-sectional view of the machined surface shape of the workpiece machined by the processing device, exaggerated in the vertical direction. FIG. 21, which is a flowchart of the operation, is a diagram showing its effect. In the figure, (1) is the workpiece, (2) is the tool electrode, and (4) is the workpiece.
) is machining fluid, (7) is machining fluid supply device, (11) is electrolytic current power supply, (12) is control device, (I3) is electrode position control section, (14) is machining fluid control section, (15) (16) is the human power device, (17) is the display device, (1
8) is the optimum pulse current calculation means, (19) is the applied current amount calculation means per unit area, (20) is the applied total flow rate calculation means, (21) is the total applied pulse number calculation means, and (22) is the machining time. Calculation/means, (24) is processing stop means, (25)
(26) is a processing enlargement calculation means, (26) is a display means, (60)
is the machining fluid intermittent supply path, (61) is the adjustment valve, (6
2) is a flow meter, and (63) is a machining liquid constant supply path. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (6)

[Claims] (1) A tool electrode and a workpiece are faced to each other with a set machining gap value, an electrolyte is interposed between the tool electrode and the workpiece, and a pulse current is supplied to process the workpiece. An electrolytic machining method characterized in that the total current amount of the pulse current is set based on the surface roughness of the workpiece before machining and the target surface roughness. (2) A tool electrode and a workpiece are faced to each other with a set machining gap value, an electrolyte is interposed between the tool electrode and the workpiece, and a pulse current is supplied to process the workpiece. In the electrolytic machining method, the total current amount of the pulsed current is set based on the surface roughness of the workpiece before processing and the target surface roughness, and the pulsed current is divided into divided pulsed currents to obtain the total current amount. An electrolytic processing method characterized by: (3) An electrode position control unit that outputs a command to the tool electrode drive means according to a set machining gap value formed between the tool electrode and the workpiece, and a pulse current that is applied between the tool electrode and the workpiece. In an electrolytic processing apparatus equipped with a control device having a processing condition control section that sets the peak current value, pulse width, and pulse period of and outputs a command according to the set values to the electrolytic current power source, the electrode position control section From the set machining gap value and the machining area input to the control device,
An electrolytic processing apparatus characterized by comprising an optimum pulse current calculation means for calculating an optimum peak current value and an optimum waveform change rate of the pulse current according to a predetermined relationship, and setting the optimum peak current value and optimum waveform change rate of the pulse current as processing conditions in the processing condition control section. . (4) An electrode position control unit that outputs a command to the tool electrode drive means according to a set machining gap value formed between the tool electrode and the workpiece, and a pulse current that is applied between the tool electrode and the workpiece. a machining condition control unit that sets the peak current value, pulse width, and pulse period of the , and outputs a command according to the set values to the electrolytic current power source, and a machining fluid supply control command between the tool electrode and the workpiece. In an electrolytic machining apparatus equipped with a control device having a machining fluid control unit that outputs the machining fluid to the machining fluid supply device, it is possible to calculate the per unit machining area from the surface roughness before machining and the target surface roughness of the workpiece that are input to the control device. applied current amount calculation means per unit area for calculating the applied current amount, total applied current amount calculation means for calculating the total applied current amount from the calculation result of this means and the machining area of the workpiece input to the control device; A total number of applied pulses calculation means for calculating the total number of applied pulses from the calculation result of this means and the set peak current value and pulse width; A machining time calculation means for calculating machining time, a machining stop means for outputting a machining stop command according to the calculation result of this means, and a machining expansion allowance for calculating a machining expansion allowance from the calculation result of the applied current amount per unit area calculation means. An electrolytic machining apparatus characterized by comprising a calculation means, and a display means for displaying the calculation results of the calculation means and the machining time calculation means on a display device. (5) A tool electrode and a workpiece are faced to each other with a set machining gap value, an electrolyte is interposed between the tool electrode and the workpiece, and a pulse current is supplied to process the workpiece. An electrolytic processing apparatus comprising: an adjusting means for adjusting the peak current value and waveform shape of the pulsed current to set values. (6) A tool electrode and a workpiece are faced to each other with a set machining gap value, and an electrolytic solution is interposed between the tool electrode and the workpiece, and a pulse current is supplied to eliminate electrolytic products in the machining gap. In an electrolytic processing device that processes the workpiece by intermittently supplying a machining fluid during the pause time of the pulse current to remove the electrolytic generation, processing in which a large amount of machining fluid is intermittently supplied to remove the electrolytic generation. An electrolytic machining device characterized in that, in addition to the intermittent liquid supply path, a machining fluid constant supply path is provided for constantly supplying a small amount of machining fluid during electrolytic machining.