CN208099568U - Arc ignition circuit for argon arc welding machine - Google Patents
Arc ignition circuit for argon arc welding machine Download PDFInfo
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- CN208099568U CN208099568U CN201820333706.3U CN201820333706U CN208099568U CN 208099568 U CN208099568 U CN 208099568U CN 201820333706 U CN201820333706 U CN 201820333706U CN 208099568 U CN208099568 U CN 208099568U
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- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 title claims abstract description 48
- 238000003466 welding Methods 0.000 title claims abstract description 48
- 229910052786 argon Inorganic materials 0.000 title claims abstract description 24
- 238000001514 detection method Methods 0.000 claims abstract description 8
- 239000003990 capacitor Substances 0.000 claims description 13
- 230000005611 electricity Effects 0.000 claims description 12
- 239000003381 stabilizer Substances 0.000 claims description 4
- 238000000034 method Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 239000004411 aluminium Substances 0.000 description 5
- 229910052782 aluminium Inorganic materials 0.000 description 5
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 4
- 230000000977 initiatory effect Effects 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000007789 gas Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010891 electric arc Methods 0.000 description 1
- -1 ferrous metals Chemical class 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
Landscapes
- Generation Of Surge Voltage And Current (AREA)
Abstract
The utility model discloses a kind of arc ignition circuit for argon arc welding machine, which is characterized in that including：One single-chip microcontroller, given value of current circuit, driving circuit, loop circuit and hall signal detection unit；The single-chip microcontroller judges whether welding current is greater than a preset value, and exports low and high level signal according to judging result；The given value of current circuit exports a drive input signal according to the low and high level signal；The driving circuit exports a drive output signal to the loop circuit according to the drive input signal；The loop circuit exports striking electric current according to the drive output signal；The hall signal detection unit detects the loop circuit and exports to the single-chip microcontroller.
Description
Technical field
The present invention relates to alternating current-direct current argon arc welding technology field, in particular to a kind of arc ignition circuit of alternating current-direct current argon arc welding.
Background technique
Argon arc welding technology is that based on the principle of ordinary arc welding, the protection using argon gas to metal wlding passes through
High current makes wlding be melted into liquid on the base material to be welded, makes to be welded metal and wlding reaches a kind of welding skill of metallurgical bonding
Art prevents wlding from contacting with the oxygen in air, to prevent weldering due to constantly serving argon gas in high-temperature fusion weld
The oxidation of material, therefore the non-ferrous metals such as copper, aluminium, steel alloy can be welded.Argon arc welding technology has welding process stabilization, receives arc control
The easy advantage of system, but striking difficulty is its existing technical problem always.
Striking difficulty is mainly to be determined by the physical characteristic of AC power source.AC welding process electric arc has zero crossing,
When electric power polarity changes, so resulting in striking hardly possible, it is easy current interruption.By taking metallic aluminium as an example, metallic aluminium is in industrial production and daily
Using very extensive in life, but the welding usability of aluminium and its alloy is very poor, simultaneously because in the presence of argon arc welding technology
Striking difficulty problem, cause metallic aluminium welding procedure to be difficult to improve.
The striking mode of argon arc welding is generally divided into contact starting and contactless striking two major classes.Traditional craft is made an arc
Contact starting mode be easy to cause the scaling loss of tungsten electrode, workpiece surface scratch and phenomena such as weld seam tungsten inclusion, should not generally adopt
With.Widely applied in argon arc welding at present is non-contact starting mode, and contactless striking includes high-voltage pulse thread-leading arc and height
Frequency high-voltage arc strike.The air gap that high-voltage pulse thread-leading arc can puncture is smaller, and striking effect is poor.High-frequency and high-voltage striking is in striking moment
High current improves arcing initiation success rate, but can cause many inconvenience in actual use in this way, such as carries out plate sheet welding
When, the high current of moment can puncture plate, damage welding workpiece.
Therefore it is badly in need of a kind of new arc stricking techniques in the prior art, improve arcing initiation success rate and avoids the occurrence of instantaneous large-current
The phenomenon that.
Summary of the invention
In view of this, the present invention provides a kind of arc ignition circuit, it can be improved arcing initiation success rate and avoid the occurrence of moment big electricity
The phenomenon that stream.
In order to solve the above technical problem, the present invention provides a kind of arc ignition circuits for argon arc welding machine, which is characterized in that
Including：One single-chip microcontroller, given value of current circuit, driving circuit, loop circuit and hall signal detection unit；Single-chip microcontroller judgement
Whether welding current is greater than a preset value, and exports low and high level signal according to judging result；The given value of current circuit is according to this
Low and high level signal exports a drive input signal；The driving circuit exports a drive output signal according to the drive input signal
To the loop circuit；The loop circuit exports striking electric current according to the drive output signal；Hall signal detection unit detection
The loop circuit is simultaneously exported to the single-chip microcontroller.
Further, which is 50 amperes.
Further, when which is less than the preset value, which exports DC pulse signal；The welding
When electric current is greater than the preset value, which exports pulse signal.
Further, which includes triangle wave generating circuit and comparator U3A, comparator U3A's
Anode is connect with the output end of single-chip microcontroller, and when the single-chip microcontroller exports low level signal, comparator U3A exports square-wave signal,
When the single-chip microcontroller exports high level signal, comparator U3A exports DC signal.
Further, which includes voltage-stablizer ZD1 and ZD2.
Further, the given value of current circuit further include resistance R1, R2, R3, R4, R5, capacitor C1 and comparator U1A,
U2A；The cathode of comparator U1A is grounded, anode the connection resistance R1, R2；The one end resistance R1 connects comparator U1A's
Anode, the other end connect resistance R3；The output end of the other end connection comparator U1 of resistance R3；One end of resistance R4 connects
Voltage-stabiliser tube ZD2 is met, the other end connects the cathode of comparator U2A；The anode connection resistance R5 of comparator U2A, cathode connection
The cathode of comparator U3；The cathode other end that the one end capacitor C1 connects comparator U2A connects the defeated of comparator U2A
Outlet.
Further, when which is DC signal, which is pulse signal；The drive
When dynamic input signal is square-wave signal, which is two-way complementation square wave.
Further, which further includes capacitor C2, C3, phase inverter U1B, U2B, U3B, diode D1 and electricity
Hinder in parallel with diode D2 and resistance R6 after R7 connects, one end connection phase inverter U2B of capacitor C2, other end ground connection；It should
The output end of one end connection given value of current circuit of phase inverter U1B, the other end connect the diode D3, D4；Diode D3 with
It is in parallel with diode D4 and resistance R8 after resistance R9 series connection；The one end capacitor C3 connects reverser U3B, other end ground connection；This is anti-
To device U2B output end and reverser U2B output to P1.
Further, which includes an inverter circuit and secondary inverter circuit.
Further, when which detects that the loop circuit exports arc ignition circuit, output one is anti-
Feedback signal to the chip microcontroller striking mode switching.
Compared with prior art, intelligent arc ignition circuit provided by the present invention can detect welding current value, judge the electricity
Whether flow valuve exceeds a preset current value, and the switching of striking mode is realized according to current value size, judges ability after striking success
Switch to normally exchange output, solves the technical problem of the too small striking difficulty of alternating current, it will not during striking
There is instantaneous large-current and damages welding workpiece.
Detailed description of the invention
Attached drawing for a better understanding of the present invention, does not constitute an undue limitation on the present invention.Wherein：
Fig. 1 is the schematic diagram of intelligent striking method of the present invention；
Fig. 2 is the structural schematic diagram of arc ignition circuit provided by the present invention；
Fig. 3 is the circuit diagram of arc ignition circuit provided by the present invention.
Specific embodiment
Core of the invention thought is to provide intelligent arc ignition circuit, which detects welding current value, sentences
Whether the current value that breaks exceeds a preset current value, and the switching of striking mode is realized according to current value size, solves exchange
Instantaneous large-current damage welding workpiece will not occur during striking in the technical problem of the too small striking difficulty of electric current.
To keep the purpose of the present invention, advantages and features clearer, below in conjunction with 1~3 pair of intelligence proposed by the present invention of attached drawing
Energy arc initiation device is described in further detail.It should be noted that attached drawing is all made of very simplified form and using non-accurate
Ratio, only for the purpose of facilitating and clarifying the purpose of the embodiments of the invention.
As used in this specification, singular "a", "an" and "the" includes plural reference, unless interior
In addition appearance explicitly points out outer.It is as used in this specification, term "or" be usually to include the meaning of "and/or" and into
Enforcement, in addition in addition non-content explicitly points out.
Fig. 1 is the schematic diagram of intelligent striking method of the present invention.As shown in Figure 1, horizontal axis is the time, the longitudinal axis is pre-
Set size of current.Intelligence arc ignition circuit of the present invention is mainly the side that striking is selected according to preset welding current
Formula.When welding current is less than 50A, using pulse direct current striking mode, striking is directly exchanged when welding current is greater than 50A.
It in this way can be to avoid the exchange rare problem of low current striking.When welding current is less than 50A, used in the moment of exchange striking straight
Pulse output is flowed, the background current of DC pulse is minimum current 5A, and peak point current is the preset current of exchange.When striking success
Afterwards, then switch to normally exchange output.
Fig. 2 is the structural schematic diagram of arc ignition circuit.The arc ignition circuit includes single-chip microcontroller 10, given value of current circuit 20, driving
Circuit 30, loop circuit 40 and hall signal feedback 50.Predetermined current inputs single-chip microcontroller 10, and single-chip microcontroller 10 is used to judge to weld
Whether electric current is greater than 50A, and exports corresponding voltage signal.Given value of current circuit 20 receives the voltage letter of the output of single-chip microcontroller 10
Number, and the voltage signal is changed into a drive input signal.Drive input signal is exported to driving circuit 30.When welding current is small
When 50A, driving circuit 30 exports DC pulse signal, when welding current is greater than 50A, exports pulse signal.Circuit
Circuit 40 exports striking electric current according to the pulse signal of output.The arc ignition circuit further includes hall signal feed circuit 50, this is suddenly
Your signal feedback circuit 50 passes through sampling output loop circuit 40 and judges whether striking succeeds, and then exports feedback signal realization
The switching of striking mode.
Fig. 3 is the circuit diagram of arc ignition circuit provided by the present invention.Electric current on the panel of argon arc welding machine sets electricity
The voltage at position device both ends increases with the increase of electric current.Predetermined current input single-chip microcontroller in, single-chip microcontroller to input current whether
Judged greater than 50A, corresponding low and high level signal is exported according to the result of judgement.Low and high level signal is given with electric current
Determine the anode connection of the comparator of circuit 20.
Given value of current circuit 20 includes resistance R1, R2, R3, R4, R5, capacitor C1, the triangular wave of voltage-stabiliser tube ZD1, ZD2 composition
Circuit and comparator U1A, U2A, U3A composition occurs.Wherein, the cathode ground connection of comparator U1A, anode connection resistance R1, R2.
The one end resistance R1 connects the anode of comparator U1A, and the other end connects resistance R3.The other end connection comparator U1's of resistance R3 is defeated
Outlet.One end of resistance R4 connects voltage-stabiliser tube ZD2, and the other end connects the cathode of comparator U2A.The anode connection of comparator U2A
Resistance R5, cathode connect the cathode of comparator U3.The cathode other end that the one end capacitor C1 connects comparator U2A connects comparator
The output end of U2A.The low and high level signal that single-chip microcontroller 10 exports connects with the anode with the comparator U3A of given value of current circuit 20
It connects.If single-chip microcontroller judges that input current value is greater than 50A, single-chip microcontroller exports low level, and given value of current circuit 20 sends out triangular wave
The triangular wave that raw device generates is converted to square wave.If single-chip microcontroller judges that input current value is less than 50A, single-chip microcontroller exports high level,
Triangular wave is converted to DC driven signal by given value of current circuit 20.
The square wave or direct current signal that driving circuit 30 is used to be exported according to given value of current circuit 20 drive DC drive circuit
Or AC driving circuit exports alternating current or direct current.Driving circuit 30 by diode D1, D2, D3, D4, resistance R6, R7, R8,
R9, capacitor C2, C3, phase inverter U1B, U2B, U3B composition.Wherein, diode D1 and resistance R7 series connection after with diode D2 and electricity
R6 parallel connection is hindered, one end of capacitor C2 connects phase inverter U2B, other end ground connection.One end of phase inverter U1B connects given value of current circuit
20 output end, the other end connect diode D3, D4.Diode D3 connect with resistance R9 after with diode D4 and resistance R8 simultaneously
Connection.The one end capacitor C3 connects reverser U3B, other end ground connection.The output end of reverser U2B and the output driving of reverser U2B
Output signal.When DC driven, direct current is linked into an inverter circuit (not shown) of loop circuit 40, then carries out whole
Stream exports direct current, carries out direct current striking.When exchange driving, exporting to go out is the square wave of two-way complementation, is linked into circuit later
In the secondary inverter circuit (not shown) of circuit 40, output alternating current carries out exchange striking.
Current signal in 40 measure loop of Hall current sensor, it is defeated that the current signal that will test is converted to voltage signal
Enter into single-chip microcontroller 10.When the current signal detected is greater than 50A, single-chip microcontroller judges striking success, exports low level.Electric current
Given circuit 20 exports square wave after receiving the low level signal that single-chip microcontroller 10 exports, and is directly entered exchange status.
Compared with prior art, intelligent arc ignition circuit provided by the present invention can detect welding current value, judge the electricity
Whether flow valuve exceeds a preset current value, and the switching of striking mode is realized according to current value size, judges ability after striking success
Switch to normally exchange output, solves the technical problem of the too small striking difficulty of alternating current, it will not during striking
There is instantaneous large-current and damages welding workpiece.
Foregoing description is only the description to present pre-ferred embodiments, not to any restriction of the scope of the invention, this hair
Any change, the modification that the those of ordinary skill in bright field does according to the disclosure above content, belong to the protection of claims
Range.
Claims (10)
1. a kind of arc ignition circuit for argon arc welding machine, which is characterized in that including：One single-chip microcontroller, given value of current circuit, driving electricity
Road, loop circuit and hall signal detection unit；The single-chip microcontroller judges whether welding current is greater than a preset value, and according to
Judging result exports low and high level signal；The given value of current circuit is according to one driving input letter of low and high level signal output
Number；The driving circuit exports a drive output signal to the loop circuit according to the drive input signal；The circuit
Circuit exports striking electric current according to the drive output signal；The hall signal detection unit detects the loop circuit and defeated
Out to the single-chip microcontroller.
2. being used for the arc ignition circuit of argon arc welding machine as described in claim 1, which is characterized in that the preset value is 50 amperes.
3. being used for the arc ignition circuit of argon arc welding machine as described in claim 1, which is characterized in that the welding current is less than described
When preset value, the driving circuit exports DC pulse signal；When the welding current is greater than the preset value, the driving electricity
Road exports pulse signal.
4. being used for the arc ignition circuit of argon arc welding machine as described in claim 1, which is characterized in that the given value of current circuit includes
The anode of triangle wave generating circuit and comparator U3A, the comparator U3A are connect with the output end of single-chip microcontroller, when the monolithic
When machine exports low level signal, the comparator U3A exports square-wave signal, when the single-chip microcontroller exports high level signal, institute
State comparator U3A output DC signal.
5. being used for the arc ignition circuit of argon arc welding machine as claimed in claim 4, which is characterized in that the triangle wave generating circuit packet
Include voltage-stablizer ZD1 and ZD2.
6. being used for the arc ignition circuit of argon arc welding machine as claimed in claim 4, which is characterized in that the given value of current circuit also wraps
Include resistance R1, R2, R3, R4, R5, capacitor C1 and comparator U1A, U2A；The cathode of the comparator U1A is grounded, anode connection institute
State resistance R1, R2；The one end the resistance R1 connects the anode of the comparator U1A, and the other end connects the resistance R3；The electricity
Hinder the output end of the other end connection comparator U1 of R3；One end of the resistance R4 connects voltage-stabiliser tube ZD2, and other end connection is compared
The cathode of device U2A；The anode connection resistance R5 of the comparator U2A, cathode connect the cathode of the comparator U3；The capacitor
The cathode other end that the one end C1 connects the comparator U2A connects the output end of the comparator U2A.
7. being used for the arc ignition circuit of argon arc welding machine as described in claim 1, which is characterized in that the drive input signal is straight
When galvanic electricity signal, the drive output signal is pulse signal；When the drive input signal is square-wave signal, the driving is defeated
Signal is two-way complementation square wave out.
8. being used for the arc ignition circuit of argon arc welding machine as described in claim 1, which is characterized in that the driving circuit further includes electricity
Hold C2, C3, phase inverter U1B, U2B, U3B, diode D1 and resistance R7 series connection after, the electricity in parallel with diode D2 and resistance R6
The one end for holding C2 connects phase inverter U2B, other end ground connection；The output of one end connection given value of current circuit of the phase inverter U1B
End, the other end connect diode D3, D4；The diode D3 is in parallel with diode D4 and resistance R8 after connecting with resistance R9；Institute
State the one end capacitor C3 connection reverser U3B, other end ground connection；The output of the output end and reverser U2B of the reverser U2B is extremely
P1。
9. being used for the arc ignition circuit of argon arc welding machine as described in claim 1, which is characterized in that the loop circuit includes primary
Inverter circuit and secondary inverter circuit.
10. being used for the arc ignition circuit of argon arc welding machine as described in claim 1, which is characterized in that the hall signal detection is single
When member detects the loop circuit output arc ignition circuit, a feedback signal cutting to the chip microcontroller striking mode is exported
It changes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820333706.3U CN208099568U (en) | 2018-03-12 | 2018-03-12 | Arc ignition circuit for argon arc welding machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820333706.3U CN208099568U (en) | 2018-03-12 | 2018-03-12 | Arc ignition circuit for argon arc welding machine |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN208099568U true CN208099568U (en) | 2018-11-16 |
Family
ID=64126188
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201820333706.3U Withdrawn - After Issue CN208099568U (en) | 2018-03-12 | 2018-03-12 | Arc ignition circuit for argon arc welding machine |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN208099568U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108555420A (en) * | 2018-03-12 | 2018-09-21 | 上海威特力焊接设备制造股份有限公司 | Arc ignition circuit for argon arc welding machine |
-
2018
- 2018-03-12 CN CN201820333706.3U patent/CN208099568U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108555420A (en) * | 2018-03-12 | 2018-09-21 | 上海威特力焊接设备制造股份有限公司 | Arc ignition circuit for argon arc welding machine |
| CN108555420B (en) * | 2018-03-12 | 2024-04-26 | 上海威特力焊接设备制造股份有限公司 | Arc striking circuit for argon arc welding machine |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned | ||
| AV01 | Patent right actively abandoned | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20181116 Effective date of abandoning: 20240426 |
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| AV01 | Patent right actively abandoned |
Granted publication date: 20181116 Effective date of abandoning: 20240426 |