WO1997024202A1 - Procede et dispositif d'usinage par decharge electrique - Google Patents
Procede et dispositif d'usinage par decharge electrique Download PDFInfo
- Publication number
- WO1997024202A1 WO1997024202A1 PCT/JP1996/003890 JP9603890W WO9724202A1 WO 1997024202 A1 WO1997024202 A1 WO 1997024202A1 JP 9603890 W JP9603890 W JP 9603890W WO 9724202 A1 WO9724202 A1 WO 9724202A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- machining
- discharge
- pulse
- pulse signal
- voltage pulse
- Prior art date
Links
- 238000003754 machining Methods 0.000 title claims abstract description 68
- 238000000034 method Methods 0.000 title claims description 15
- 230000004044 response Effects 0.000 claims abstract description 10
- 238000007599 discharging Methods 0.000 abstract description 3
- 230000008569 process Effects 0.000 description 6
- 230000009471 action Effects 0.000 description 5
- 230000008859 change Effects 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 238000005260 corrosion Methods 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23H—WORKING OF METAL BY THE ACTION OF A HIGH CONCENTRATION OF ELECTRIC CURRENT ON A WORKPIECE USING AN ELECTRODE WHICH TAKES THE PLACE OF A TOOL; SUCH WORKING COMBINED WITH OTHER FORMS OF WORKING OF METAL
- B23H1/00—Electrical discharge machining, i.e. removing metal with a series of rapidly recurring electrical discharges between an electrode and a workpiece in the presence of a fluid dielectric
- B23H1/02—Electric circuits specially adapted therefor, e.g. power supply, control, preventing short circuits or other abnormal discharges
- B23H1/022—Electric circuits specially adapted therefor, e.g. power supply, control, preventing short circuits or other abnormal discharges for shaping the discharge pulse train
Definitions
- the present invention relates to an electric discharge machining apparatus and a method for machining a work piece by electric discharge using a tool electrode. More particularly, the present invention relates to an apparatus and a method for supplying an electric power pulse to a gap formed between a tool electrode and a cup using a water-based dielectric liquid.
- Japanese Patent Publication No. 5-377676 discloses a first power source for applying a high-frequency AC voltage to the machining gap, and a DC current for machining applied to the machining gap immediately after the discharge starts. It discloses a power supply for electrical discharge machines that includes a second power supply.
- the first power supply is coupled to the working gap via a coupling circuit such as a transformer or capacitor.
- An object of the present invention is to provide an electric discharge machining method and a shield that quickly suppress undesirable electrolytic action while maintaining high machining efficiency.
- the electric discharge machining apparatus of the present invention for machining a workpiece by generating an electric discharge in a machining gear formed between a work piece and a tool electrode is capable of discharging the electric discharge generated in the machining gear.
- Discharge detector to detect; Responds to discharge detector and pauses after discharge starts Pulse generator that generates a pulse signal that responds to the pulse signal; a first switching circuit that applies a voltage pulse of one polarity between processing gaps in response to the pulse signal; processes a voltage pulse of the other polarity that responds to the pulse signal A second switching circuit applied between the gaps; a flip-flop holding one of the two states; a pulse signal is supplied to the first switching circuit when one of the states is held in the flip-flop.
- the method of the present invention for machining a workpiece by generating an electric discharge in a machining gap formed between the workpiece and the tool electrode alternately processes a voltage pulse of one polarity and a voltage pulse of another polarity.
- FIG. 1 is a block diagram illustrating an embodiment of the present invention applied to a wire-cut electric discharge machine.
- FIG. 2 is a circuit diagram illustrating the control circuit of FIG.
- FI GS. 3 (A), 3 (B), 3 (C), 3 (D), 3 (E), 3 (F), 3 (G), 3 (H) and 3 (1) are FI G.
- FIG. 5 is a flowchart for erasing the operations of the discharge detector, the second pulse generator, and the control circuit shown in FIG.
- the wire-cut electric discharge machine 1 is a wire driving device that conveys a wire electrode 3 unwound from a bobbin (not shown) along a predetermined conveyance path. Including 4.
- the wire driving device 4 includes current-carrying elements 4 A and 4 B that are arranged on the wire transport path and transmit current to the traveling wire electrode 3. work piece
- Numeral 2 is arranged opposite to the wire electrode 3, and a gap 5, a so-called “gap” is formed between the workpiece 2 and the traveling wire electrode 3.
- the mechanical part of the wire cut release processing apparatus 1 has a known configuration, and a detailed description thereof is omitted.
- the wire-cut electric discharge machine 1 includes a machining current supply unit 10 for supplying electric energy to the gap 5 for machining the workpiece 2.
- the machining current supply unit 10 includes a DC power supply 11 having a negative terminal electrically connected to the wire electrode 3 via the conducting elements 4 A and 4 B, and a positive terminal electrically connected to the work piece 2.
- the DC power supply 1
- the machining current supply unit 10 includes a second pulse generator 13 that provides a gate pulse signal GP2 that turns on the switching transistor 12 in response to the occurrence of discharge.
- the machining current I from the DC power supply 11 is supplied to the machining gap by the "1" level signal GP2 having the time width TN.
- the time T N determines the duration of the flow of the machining current I through the gap 5 and is set, for example, by a thumbwheel switch provided in the second pulse generator 13. Alternatively, data representing the time T N may be externally provided to the second pulse generator 13 in the form of a digital signal.
- the wire cut electric discharge machine 1 includes a trigger voltage supply unit 20 for alternately applying a voltage pulse of one polarity and a voltage pulse of the other polarity between the gaps 5 in order to generate a discharge in the gap 5.
- the trigger voltage supply section 20 is connected to the DC power supply 21
- a switching circuit 22 for switching the polarity of the pressure pulse is included.
- the switching circuit 22 is a bridge circuit including switching transistors 22A, 22B, 22D and 22C connected in series as illustrated in FIG.
- the connection point A of the switching transistors 22 B and 22 D is connected to the negative terminal of the DC power supply 21, and the connection point B of the switching transistors 22 C and 22 A is connected to the current limiting resistors 23 and Connected to the positive terminal of DC power supply 21 via diode 25.
- the connection point C of the switching transistors 22A and 22B is electrically connected to the wire electrode 3 via the current-carrying elements 4A and 4B, and the connection point D of the switching transistors 22D and 22C is Electrically connected
- a DC voltage pulse from the DC power supply 21 is applied across the gap 5 with so-called straight polarity.
- the workpiece 2 may be subjected to electrolytic corrosion.
- the cycle of the change in the polarity of the voltage pulse is determined by the repetition cycle of the on / off switching of the switching transistor.
- the trigger voltage supply unit 20 alternately applies a straight-polarity voltage pulse and a reverse-polarity voltage pulse between the gaps 5 so that one set of switching transistors and the other set are turned on alternately.
- the output pulse signal S 1 of the control circuit 24 is connected to one set of the switching transistors 22 A and
- the 22D output pulse signal S2 is supplied to the other set of switching transistors 22B and 22C.
- the control circuit 24 turns on one set of switching transistors and the other set alternately at predetermined short time intervals TW to generate discharge, and immediately turns off both sets of switching transistors after the start of discharge. Turn off only during This pause time TM is longer than the duration TN set in the second pulse generator 13. The difference between time TM and time TN determines the period during which no voltage is applied across gap 5.
- the wire-cut electric discharge machine 1 further includes a discharge detector 30 that detects a discharge generated by application of a high-frequency voltage pulse from the DC power supply 21.
- the branch voltage generated between the connection point B of the switching transistors 22C and 22A and the connection point A of the switching transistors 22B and 22D is extracted by the two resistors 31 and 32.
- a voltage signal EG representing the branch voltage is provided to the discharge detector 30.
- the level of the voltage signal EG is substantially equal to the terminal voltage E of the DC power supply 21 when discharge has not yet occurred, and becomes lower than the voltage E due to the voltage drop in the resistor 23 when the discharge current flows through the gap 5.
- the discharge detector 30 compares the level of the voltage signal EG with the reference voltage level, and supplies the output signal K to the second pulse generator 13 and the control circuit 24.
- the output signal K indicates the "0" level only when the machining current I flows through the gap 5.
- the control circuit 24 provides a gate pulse signal GP1 for turning on one of the switching transistors 22A and 22D of one set and the switching transistors 22B and 22C of the other set.
- a gate pulse signal GP1 for turning on one of the switching transistors 22A and 22D of one set and the switching transistors 22B and 22C of the other set.
- a voltage pulse from the DC power supply 21 is applied between the machining gaps 5 by the "1" level signal GP1.
- the pulse signal GP1 indicates the "0" level only during the pause time TM.
- Data D off indicating this pause time TM is externally applied to the first pulse generator 41.
- Pulse signal GP 1 is connected to AND gates 42 43 and 51 and one-shot Supplied to the output 44 A of the chiever 44.
- the one-shot multivibrator 44 responds to the change of the level of the panorama signal GP1 from “1" to "0", and outputs a "1" level pulse signal having a time width W at its output 44B. I will provide a.
- the pulse signal of the one-shot multivibrator 44 is supplied to the input terminal T of the T flip-flop 46 through the OR gate 45, the level of the output terminal Q of the T flip-flop 46 is switched.
- the T flip-flop 46 is a circuit that holds only one of the two states and switches the internal state when an external signal is supplied to its input terminal T.
- the output terminal Q of the T flip-flop 46 is connected to the AND gate 43 and to the AND gate 42 via the inverter 47.
- the output signal S1 of the AND gate 43 is sent to a set of switching transistors 22A and 22D, and the output signal S2 of the AND gate 42 is sent to a set of switching transistors 22B and 22C. .
- control circuit 24 includes a binary counter 48 that provides binary data KD from an output terminal Q indicating the number of clock pulses sent from a clock pulse generator (not shown).
- the comparator 49 compares the binary data KD received at the input terminal A with the binary data Dr received at the input terminal B. This data Dr determines the duration TW of the ⁇ frequency voltage pulse.
- the output pulse AB indicating the "1" level of the comparator 49 is supplied to the input terminal T of the T flip-flop 46 through the OR gate 45, the level of the output terminal Q of the T flip-flop 46 is switched.
- the level of the output terminal Q of the T flip-flop 46 is switched every time TW.
- the counter 48 receives a "0" level signal at its reset terminal CLR, the counter 48 returns the count to "0".
- FI GS. 3 (A), 3 (B), 3 (C), 3 (D), 3 (E), 3 (F), 3 (G), 3 (H), 3 (1) and FI G The operation of the control circuit 24 and the second pulse generator 13 shown in FIG. 1 will be described with reference to FIG.
- Steps S100 to S170 of FIG. 5 show the operation of the control circuit 24.
- step S100 when the output Q of the T flip-flop 44 illustrated in FIG. 3 (G) indicates the "0" level at time tO, the process proceeds to step S110.
- step S 110 as illustrated in FIGS. 3 (I) and 3 (H), at time t 0, the output signal S 2 of the AND gate 42 indicates the “1” level and the AND gate The output signal S1 in step 43 indicates the "0" level. Therefore, at this time, switching transistors 22B and 22C are on, 22A and 22D are off, and a straight-polarity voltage pulse is applied across gap 5 as shown in FIG. 3 (D). Applied.
- step S 130 When the first pulse generator 41 receives the signal K indicating the “1” level in step S 120, in other words, when no discharge occurs in the gap 5, the process proceeds to step S 130.
- step S140 the level of the output terminal Q of the T flip-flop 46 at step S100 indicates "1", so the process proceeds to step S112.
- step S112 as illustrated in FIGS. 3 (I) and 3 (H), at time t1, the output signal S2 of the AND gate 42 indicates the "0" level and the AND gate G Output signal S of 43 1 indicates the "1" level. Therefore, at this time, the switching transistors 22 A and 22 D are on, the switches 22 B and 22 C are off, and a voltage pulse of the opposite polarity is applied between the gaps 5.
- Fig. 3 (D) the polarity of the voltage pulse applied between gaps 5 at times t1, t2, t3, and t4 until discharge occurs Can be switched.
- the level of the output terminal Q of the T flip-flop 46 changes from "1" to "0".
- step S120 When the level of signal K changes from “1” to “0" at time t5 as illustrated in FIG. 3 (A) in step S120, the process proceeds to steps S150 and S160. move on.
- step S150 as illustrated in FIG. 3 (C)
- the level of the pulse signal GP1 changes from “1” to "0” at time t5.
- the pulse signal GP1 indicates “0" level
- the output signals S1 and S2 of the AND gates 43 and 42 also indicate “0”. Therefore, during the pause time TM from time t5 to time t7, switching transistors 22A, 22B, 22C and 22D are all off, and DC power supply 21 is cut off from gap 5.
- step S160 the one-shot multivibrator 44 supplies the output signal to the input terminal T of the T flip-flop 46, so that the level of the output terminal Q changes from “0" to “1”. .
- step S170 the level of pulse signal GP1 changes from “0” to "1” at time t7 so as to be frustrated during FIG. 3 (C). You.
- the level of the output terminal Q of the T flip-flop 46 indicates “1"
- the AND gate 43 passes the "1" level signal GP1 as the signal S1.
- step S160 The technical significance of step S160 is that the polarity of the voltage pulse supplied from DC power supply 21 at time t7 is opposite to the polarity of the voltage pulse supplied from time t4 to t5. Thus, regardless of the length of the discharge waiting time, the electrolytic action is suppressed by the voltage pulse applied between the gaps 5 only after the end of the discharge.
- the one-shot multivibrator 44 changes the level of the output Q of the T flip-flop 46 as soon as a discharge is detected.
- the level of the output Q of the flip-flop 46 may be varied during the pause TM of the pulse signal GP1.
- Steps S200 to S230 of FIG. 5 show the operation of the second pulse generator 13.
- the level of the output signal GP2 of the second pulse generator 13 changes from “0” to “1” in step S210.
- the switching transistor 12 is turned on.
- the pulse signal GP 2 changes at time t 6 when the time TN has elapsed since its level changed from “0” to “1”. It shows "0" level again.
- the switching transistor 12 is turned off in step S230 in response to the signal GP2 at the "0" level.
- FI GS. 4 (A), 4 (B), 4 (C), 4 (D) and 4 (E) are timing charts for illuminating the voltage Vgap and the current I flowing through the machining gap, respectively.
- FI GS. 4 (B), 4 (C) and 4 (D) are timing charts illustrating control signals GP2, S1 and S2 for the switching transistor, respectively.
- the application of the voltage pulse of the DC power supply 21 is started at times B, ta, tc, and te, and the discharge is started at times tb, td, and tf.
- the level of the pulse signal GP2 changes from “0" after a slight delay from the start of the discharge, as illustrated in Fig. 4 (D). Changes to "1".
- the level of pulse signal GP1 changes from "1" to "0” after a slight delay from the start of discharge. .
- the pulse signal GP1 passes through the AND gate 43 and is supplied to one set of switching transistors 22A and 22D in the form of a signal S1.
- the voltage pulse from the DC power supply 21 has a width of 1 to 100 ⁇ sec. I do. Signals S 1 and S 2 are always applied alternately, as illustrated in FI GS. 4 (B) and 4 (C). As a result, as illustrated in FI GS. 4 (A), a voltage pulse of one polarity and a voltage pulse of the other polarity are always alternately applied from the DC power supply 21 to the gap 5. Therefore, regardless of the length of the discharge waiting time, the electrolytic action is suppressed by the first voltage pulse supplied from DC power supply 21 after the end of discharge.
- the switching transistors 22 A, 22 B, 22 C, and 22 D are all turned off after the occurrence of discharge is detected, the machining current I from the machining current supply unit 10 does not flow to the DC power supply 21. Therefore, the machining current I is efficiently supplied to the gap 5.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP96943348A EP0812643B1 (en) | 1995-12-28 | 1996-12-27 | Device and method for electric discharge machining |
DE69629180T DE69629180T2 (de) | 1995-12-28 | 1996-12-27 | Funkenerosionsvorrichtung und verfahren |
US08/875,922 US5986232A (en) | 1995-12-28 | 1996-12-27 | Electrical discharge machining apparatus and electrical discharge machining method |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7/352175 | 1995-12-28 | ||
JP35217595A JP3645957B2 (ja) | 1995-12-28 | 1995-12-28 | 放電加工方法及び装置 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1997024202A1 true WO1997024202A1 (fr) | 1997-07-10 |
Family
ID=18422296
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP1996/003890 WO1997024202A1 (fr) | 1995-12-28 | 1996-12-27 | Procede et dispositif d'usinage par decharge electrique |
Country Status (5)
Country | Link |
---|---|
US (1) | US5986232A (ja) |
EP (1) | EP0812643B1 (ja) |
JP (1) | JP3645957B2 (ja) |
DE (1) | DE69629180T2 (ja) |
WO (1) | WO1997024202A1 (ja) |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3390652B2 (ja) * | 1998-02-10 | 2003-03-24 | 株式会社ソディック | 放電加工装置 |
US6222149B1 (en) * | 1998-06-10 | 2001-04-24 | Sodick Co., Ltd. | Power supply device for electric discharge machining apparatus |
JPH11347845A (ja) * | 1998-06-10 | 1999-12-21 | Sodick Co Ltd | 放電加工用パルス電圧発生方法及び回路 |
US6107593A (en) * | 1998-12-21 | 2000-08-22 | Industrial Technology Research Institute | Power apparatus for wire electric discharge machine |
CH693529A5 (fr) * | 1999-11-05 | 2003-09-30 | Charmilles Technologies | Procede et dispositif d'usinage par electroerosion. |
JP4437612B2 (ja) * | 2000-11-21 | 2010-03-24 | 三菱電機株式会社 | 放電加工装置 |
JP3835452B2 (ja) | 2002-06-12 | 2006-10-18 | 三菱電機株式会社 | ワイヤ放電加工機の加工電源装置 |
WO2005034227A1 (en) | 2003-10-08 | 2005-04-14 | Semes Co., Ltd | Facility with multi-storied process chamber for cleaning substrates and method for cleaning substrates using the facility |
US20050247569A1 (en) * | 2004-05-07 | 2005-11-10 | Lamphere Michael S | Distributed arc electroerosion |
US8323473B2 (en) | 2004-11-23 | 2012-12-04 | General Electric Company | Methods and systems for monitoring and controlling electroerosion |
US20080142488A1 (en) * | 2006-12-19 | 2008-06-19 | General Electric Company | Compound electrode, methods of manufacture thereof and articles comprising the same |
CN102245716B (zh) | 2008-10-10 | 2014-03-12 | 特密高股份有限公司 | 聚合物膜包覆的碳颗粒、生产及使用其的方法 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS614620A (ja) * | 1984-06-20 | 1986-01-10 | Mitsubishi Electric Corp | 放電加工用電源装置 |
JPS6368317A (ja) * | 1986-09-09 | 1988-03-28 | Brother Ind Ltd | 放電加工機 |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2939310B2 (ja) * | 1990-08-14 | 1999-08-25 | 株式会社ソディック | 放電加工装置 |
CH684632A5 (fr) * | 1991-02-18 | 1994-11-15 | Charmilles Technologies | Dispositif anti-corrosion dans une machine d'usinage par électro-érosion à fil-électrode. |
JPH0537766A (ja) * | 1991-07-26 | 1993-02-12 | Nec Corp | フアクシミリ装置 |
JP3343267B2 (ja) * | 1992-08-25 | 2002-11-11 | 株式会社ソディック | 放電加工方法及び放電加工用電源装置 |
US5416290A (en) * | 1992-10-08 | 1995-05-16 | Mitsubishi Denki Kabushiki Kaisha | Electric discharge machine power supply circuit |
JP3057953B2 (ja) * | 1993-02-25 | 2000-07-04 | 株式会社ソディック | ワイヤカット放電加工装置 |
JP2914102B2 (ja) * | 1993-06-30 | 1999-06-28 | 三菱電機株式会社 | 放電加工機 |
JPH07290317A (ja) * | 1994-04-25 | 1995-11-07 | Fanuc Ltd | 放電加工方法及びその装置 |
-
1995
- 1995-12-28 JP JP35217595A patent/JP3645957B2/ja not_active Expired - Lifetime
-
1996
- 1996-12-27 WO PCT/JP1996/003890 patent/WO1997024202A1/ja active IP Right Grant
- 1996-12-27 US US08/875,922 patent/US5986232A/en not_active Expired - Lifetime
- 1996-12-27 EP EP96943348A patent/EP0812643B1/en not_active Expired - Lifetime
- 1996-12-27 DE DE69629180T patent/DE69629180T2/de not_active Expired - Lifetime
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS614620A (ja) * | 1984-06-20 | 1986-01-10 | Mitsubishi Electric Corp | 放電加工用電源装置 |
JPS6368317A (ja) * | 1986-09-09 | 1988-03-28 | Brother Ind Ltd | 放電加工機 |
Also Published As
Publication number | Publication date |
---|---|
DE69629180D1 (de) | 2003-08-28 |
JPH09183019A (ja) | 1997-07-15 |
DE69629180T2 (de) | 2004-01-29 |
EP0812643A1 (en) | 1997-12-17 |
JP3645957B2 (ja) | 2005-05-11 |
EP0812643B1 (en) | 2003-07-23 |
US5986232A (en) | 1999-11-16 |
EP0812643A4 (en) | 2000-08-23 |
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