WO1993024265A1 - Insulation tester for wire cut electrical discharging machine - Google Patents
Insulation tester for wire cut electrical discharging machine Download PDFInfo
- Publication number
- WO1993024265A1 WO1993024265A1 PCT/JP1993/000692 JP9300692W WO9324265A1 WO 1993024265 A1 WO1993024265 A1 WO 1993024265A1 JP 9300692 W JP9300692 W JP 9300692W WO 9324265 A1 WO9324265 A1 WO 9324265A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- voltage
- switching element
- wire electrode
- capacitor
- insulation
- Prior art date
Links
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
- B23H7/00—Processes or apparatus applicable to both electrical discharge machining and electrochemical machining
- B23H7/02—Wire-cutting
- B23H7/04—Apparatus for supplying current to working gap; Electric circuits specially adapted therefor
-
- 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
- B23H1/024—Detection of, and response to, abnormal gap conditions, e.g. short circuits
Definitions
- the present invention relates to a wire-cut electric discharge machine, and more particularly to an insulation state detection device that detects insulation recovery between a wire electrode and a work.
- machining is performed by applying a voltage between a wire electrode and a work and generating a discharge between the wire electrode and the work.
- An insulating machining fluid is interposed between the wire electrode and the workpiece. Every time one discharge is completed, the insulation between the wire electrode and the workpiece is restored. A voltage is applied again between the wire electrode and the work, causing breakdown and causing discharge. If the next discharge is started without the insulation recovery between the wire electrode and the work after the discharge, a discharge will occur at the same location (concentrated discharge), deteriorating the precision of the machined surface or the quality of the machined surface. Is impaired. Therefore, when such a concentrated discharge occurs, the machining must be stopped.
- the present invention provides an insulation state detection device that can detect the insulation state between a wire electrode and a work without using a power supply for electric discharge machining and providing a special power supply for detection.
- An insulation state detection device includes a capacitor for storing a charging voltage applied between a wire electrode and a work, a charging switching element for charging the capacitor, and a semiconductor. And a discharging switching element for applying the charging voltage of the capacitor between the wire electrode and the work, and a period in which the discharging switching element is off. And a voltage detecting means which operates during a period including a period in which the charging switching element is on, and detects a voltage between the wire electrode and the work, and a voltage detecting means for detecting the voltage between the wire electrode and the work. Determining means for comparing the detected voltage with a set reference value and determining that the insulation is defective when the detected voltage is equal to or less than the reference value.
- the voltage detecting means can be constituted by a beak hold circuit provided with switching means and a capacitor.
- the discharging switching element is composed of a semiconductor
- the capacitor is charged by turning on the charging switching element while the switching element is off.
- a voltage is generated between the wire electrode and the work.
- This is a semiconductor Discharge switch formed: It is estimated that this is due to the influence of leakage current of the switching element. Experiments have confirmed that this voltage is generated.
- the present invention utilizes the above-mentioned phenomenon to provide a so-called off-time period in which the discharging switching element is off, and that the charging switching element is on.
- the voltage detection means detects the voltage between the wire electrode and the work.
- the insulation failure can be detected by comparing the voltage between the wire electrode and the work with the reference value using a comparator.
- FIG. 1 is a block diagram of a main part of a power supply device for electric discharge machining and an insulation state monitoring device according to an embodiment of the present invention.
- Fig. 2 is a block diagram showing the circuit configuration of the insulation condition monitoring device shown in Fig. 1.
- Fig. 3 is a timing chart of the operation of the insulation state monitoring device shown in Figs.
- a capacitor 4 is connected to a machining DC power supply 1 via a charging switching element 2.
- One end of the capacitor 4 is connected to the work 6, and the other end is connected to the wire electrode 5 via the discharge switching element 3.
- Such an electric discharge machine power supply circuit includes a charging switching element.
- the discharging switching element 3 is made of a semiconductor.
- An insulation state monitoring device 7 for detecting the insulation state between the wire electrode 5 and the work 6 is connected to the electric discharge machining part of the wire electrode 5 and the work 6.
- the charging switching element 2 When the charging command S1 is input to the charging switching element 2, the charging switching element 2 is turned on, and the capacitor 4 is charged by the DC power supply 1. You. After a predetermined time has elapsed, the charging signal S1 is turned off, and the charging switching element 2 is turned off. After a predetermined time delay, the discharge command S2 is input to the switching element 3 for discharging, the switching element 3 for discharging is turned on, and the connection between the wire electrode 5 and the work 6 is established. The charging voltage of capacitor 4 is applied. As a result, a discharge occurs between the wire electrode 5 and the work 6. Then, when the discharge current becomes equal to or less than the predetermined value and the end of discharge is detected, the discharge command S2 is turned off and the switching element 3 for discharge is turned off. Hereinafter, this operation is repeated to perform discharge application. This function is the same as that of the conventional discharge heating power supply circuit of this type.
- FIG. 2 is a block diagram showing details of the insulation state monitoring device 7.
- the voltage between the wire electrode 5 and the work 6 is divided by the resistors R 1 and R 2, extracted, and amplified by the buffer amplifier 10.
- the output of the knock amplifier 10 is connected to the beak-hold switching element 11 and the capacitor 12. Input to the configured hold circuit.
- the output of the beak hold circuit is amplified by the buffer amplifier 14, and the output of the buffer amplifier 14 (beak hold voltage) VPH is input to the comparator 15 to be set to the reference. It is compared with the voltage Vs.
- the output of the comparator 15 is input to the AND circuit 17 via the inverter 16.
- the AND circuit 17 uses the output of the comparator 15 and the AND of the check pulse CH to output an insulation failure signal NG. Note that the switch circuit 13 is turned on by the reset signal RT, and discharges the capacitor 12.
- Fig. 3 shows the discharge when the insulation between the wire electrode and the work is sufficient, and the right part shows the discharge when the insulation is insufficient.
- a beak hold signal PH having the same pulse width is output from the control device to the beak hold switching element 11 of the insulation state monitoring device 7, and the switch is switched. Turn the chin element 11 on.
- the peak hold signal PH includes at least a period in which the charging switching element 2 is turned on and the capacitor 4 is charged, and the discharge switching element PH is used. As long as the switching element for beak hold 11 is on while the switch 3 is off. When the switching element for beak hold 11 is turned on, the partial voltage of the gap voltage Vg between the wire electrode 5 and the work is connected via the buffer amplifier 4 to the capacitor. 12 is applied to charge capacitor 12.
- the wire T JP93 / 00692 1 7 1 The voltage between the electrode 5 and the work 6 rises, the charging voltage of the capacitor 12 rises, and the charging voltage of the capacitor 12 is reduced by the voltage of the capacitor.
- the peak hold voltage VPH increased in step 14 rises and exceeds the reference voltage Vs set in the comparator 15. Therefore, the signal Vc obtained by inverting the output of the comparator 15 by the inverter 16 has a low level as shown on the left side of FIG.
- a check pulse CH is output from the control device, and the output signal Vc of the inverter 16 and the check signal CH are output by the AND circuit 17.
- the pulse pulse CH is ANDed, but when the insulation between the wire electrode 5 and the work 6 is sufficient, the signal Vc is at a low level and the AND circuit 17 Therefore, the insulation failure signal NG is not output. Then, when a discharge occurs between the wire electrode 5 and the work 6 and the discharge current falls below a predetermined level and the discharge end is detected, a reset pulse RT is output from the control device. The switch circuit 13 is turned on to discharge the capacitor 12 and prepare for the next voltage detection.
- the beak hold circuit is composed of the peak hold switching element 11 and the capacitor 12.
- a phenomenon occurs in which the switching element 11 for the beak Hornet is turned on, the voltage output from the amplifier 10 rises, and then the voltage rises and then falls.
- the peak voltage cannot be detected accurately, but this is not a practical problem.
- a diode In order to reliably detect the beak voltage, a diode must be connected between the connection point of the beak-hold switching element 11 and the capacitor 12 in the forward direction (buffer). It may be inserted in the direction in which current flows from fan 10 to capacitor 12).
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
Description
Claims
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/190,158 US5486765A (en) | 1992-06-04 | 1993-05-25 | Insulating condition detecting apparatus for a wire-cut electrical discharge machine |
EP9393910389A EP0597122A4 (en) | 1992-06-04 | 1993-05-25 | INSULATION TESTER FOR ELECTRIC DISCHARGE MACHINING MACHINE USING A WIRE ELECTRODE. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP4170125A JPH05337738A (ja) | 1992-06-04 | 1992-06-04 | ワイヤ電極とワーク間の絶縁状態検出装置 |
JP4/170125 | 1992-06-04 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1993024265A1 true WO1993024265A1 (en) | 1993-12-09 |
Family
ID=15899112
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP1993/000692 WO1993024265A1 (en) | 1992-06-04 | 1993-05-25 | Insulation tester for wire cut electrical discharging machine |
Country Status (3)
Country | Link |
---|---|
US (1) | US5486765A (ja) |
JP (1) | JPH05337738A (ja) |
WO (1) | WO1993024265A1 (ja) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5598075A (en) * | 1995-09-13 | 1997-01-28 | Industrial Technology Research Institute | Servo control method and apparatus for discharging machine |
US6411110B1 (en) * | 1999-08-17 | 2002-06-25 | Micron Technology, Inc. | Apparatuses and methods for determining if protective coatings on semiconductor substrate holding devices have been compromised |
JP6457261B2 (ja) * | 2014-12-29 | 2019-01-23 | 福島SiC応用技研株式会社 | 高電圧パルス発生装置 |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60180718A (ja) * | 1984-02-29 | 1985-09-14 | Fanuc Ltd | 放電加工電源 |
JPS63318222A (ja) * | 1987-06-22 | 1988-12-27 | Hoden Seimitsu Kako Kenkyusho Ltd | ワイヤ放電加工機の短絡検出装置 |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3997753A (en) * | 1969-03-17 | 1976-12-14 | Inoue K | Control system and method for electric discharge machining (EDM) using a predetermined portion of each discharge pulse for monitoring |
US3969602A (en) * | 1969-04-01 | 1976-07-13 | Ex-Cell-O Corporation | Structure for and method of electroerosion machining |
GB2055068A (en) * | 1979-07-24 | 1981-02-25 | Charmilles Sa Ateliers | Process and device for electric spark erosion machining |
CH650433A5 (en) * | 1981-04-14 | 1985-07-31 | Exnii Metallorezh Stankov | Method and apparatus for the automatic control of an electrical discharge machining operation |
CH655032A5 (fr) * | 1982-06-30 | 1986-03-27 | Mitsubishi Electric Corp | Machine a decharge electrique pour electro-erosion. |
JPS6099521A (ja) * | 1983-11-07 | 1985-06-03 | Fanuc Ltd | 放電加工機における放電制御装置 |
JPS60150912A (ja) * | 1984-01-13 | 1985-08-08 | Amada Co Ltd | 放電加工装置 |
JPS632612A (ja) * | 1986-06-18 | 1988-01-07 | Fanuc Ltd | 放電加工制御装置 |
JPH0276628A (ja) * | 1988-09-14 | 1990-03-16 | Fanuc Ltd | ワイヤ放電加工機における絶縁不良検出方法 |
-
1992
- 1992-06-04 JP JP4170125A patent/JPH05337738A/ja active Pending
-
1993
- 1993-05-25 US US08/190,158 patent/US5486765A/en not_active Expired - Fee Related
- 1993-05-25 WO PCT/JP1993/000692 patent/WO1993024265A1/ja not_active Application Discontinuation
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS60180718A (ja) * | 1984-02-29 | 1985-09-14 | Fanuc Ltd | 放電加工電源 |
JPS63318222A (ja) * | 1987-06-22 | 1988-12-27 | Hoden Seimitsu Kako Kenkyusho Ltd | ワイヤ放電加工機の短絡検出装置 |
Also Published As
Publication number | Publication date |
---|---|
US5486765A (en) | 1996-01-23 |
JPH05337738A (ja) | 1993-12-21 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4347425A (en) | Wire-cut, electric-discharge machining power source | |
US4447713A (en) | Power supply unit for electric discharge machine | |
JPS614620A (ja) | 放電加工用電源装置 | |
EP0124625B1 (en) | Electric discharge machining control circuit | |
JP3341494B2 (ja) | ワイヤ放電加工機の電源制御装置 | |
WO2003106088A1 (ja) | ワイヤ放電加工機の加工電源装置 | |
WO1993024265A1 (en) | Insulation tester for wire cut electrical discharging machine | |
EP0032023B1 (en) | A power source for an electric discharge machine | |
JP2682276B2 (ja) | 放電加工装置の電源 | |
US4431895A (en) | Power source arrangement for electric discharge machining | |
JPH0564032B2 (ja) | ||
JP6165210B2 (ja) | ワイヤ放電加工装置の加工電源装置 | |
JPS6247134B2 (ja) | ||
EP0597122A1 (en) | Insulation tester for wire cut electrical discharging machine | |
EP0147473B1 (en) | Power source for electrical discharge machining | |
JP3396515B2 (ja) | 放電加工機の電源装置 | |
EP0657242A1 (en) | Discharge device of wire-cutting electric discharge machine | |
JP2890319B2 (ja) | 放電加工機用電源回路 | |
EP3643440B1 (en) | Wire electrical discharge machine and electrical discharge machining method | |
JPH0777695B2 (ja) | 放電加工に於ける低レベル放電を検出して制御する方法と装置 | |
KR0169650B1 (ko) | 와이어 방전 가공기의 단선 방지 장치 | |
JP2680036B2 (ja) | 放電加工用電源装置 | |
KR0178584B1 (ko) | 와이어 방전 가공기의 전원 장치 | |
JPH058121A (ja) | 放電加工装置 | |
JPS63318222A (ja) | ワイヤ放電加工機の短絡検出装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): KR US |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1993910389 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 08190158 Country of ref document: US |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWP | Wipo information: published in national office |
Ref document number: 1993910389 Country of ref document: EP |
|
WWR | Wipo information: refused in national office |
Ref document number: 1993910389 Country of ref document: EP |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 1993910389 Country of ref document: EP |