CN102148600A - Speed regulating and power controlling device of wire feed motor of CO2/MAG (metal active gas)/MIG (metal insert gas) arc welding machine - Google Patents

Speed regulating and power controlling device of wire feed motor of CO2/MAG (metal active gas)/MIG (metal insert gas) arc welding machine Download PDF

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Publication number
CN102148600A
CN102148600A CN2011100843935A CN201110084393A CN102148600A CN 102148600 A CN102148600 A CN 102148600A CN 2011100843935 A CN2011100843935 A CN 2011100843935A CN 201110084393 A CN201110084393 A CN 201110084393A CN 102148600 A CN102148600 A CN 102148600A
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winding
resistance
switch transformer
pin
pulse width
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李春光
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WUXI NANFANG ELECTRIC APPLIANCE MANUFACTURING Co Ltd
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WUXI NANFANG ELECTRIC APPLIANCE MANUFACTURING Co Ltd
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Priority to CN2011100843935A priority Critical patent/CN102148600A/en
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P80/00—Climate change mitigation technologies for sector-wide applications
    • Y02P80/10—Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier

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Abstract

The invention relates to a speed regulating and power controlling device of a wire feed motor of a CO2/MAG (metal active gas)/MIG (metal insert gas) arc welding machine, and the device provided by the invention comprises a switch power source, a speed regulating circuit and two groups of power supplies, wherein the switch power source consists of a pulse modulation chip LT1247, a field effect tube and a switch transformer; the speed regulating circuit consists of a three-terminal adjustable voltage-regulator LM 338 and an external potentiometer; and the two group of power supplies are positioned at the secondary pole of the switch transformer. The speed regulating and power controlling device provided by the invention the advantages that a general power frequency control transformer is omitted, and a wire feed motor speed regulating circuit and a control power source device are simplified; the pulse modulation chip LT124 and the three-terminal adjustable integrated regulator LM338 are combined to form a switch power source device for regulating the speed of the wire feed printing motor of various CO2/MAG/MIG arc welding machines and supplying power to a +/- 15V power source required for a control circuit; the costs of various CO2/MAG/MIG arc welding machines are lowered; and especially, the device provided by the invention can better adaptive to the characteristics of small volume, light weight, efficiency and energy conservation since the power frequency control transformer is omitted.

Description

A kind of CO＜sub〉2＜/sub〉and MAG and wire feeding motor speed governing of MIG arc welder and control supply unit
Technical field
The present invention relates to a kind of wire feeding motor alignment circuit and control power supply device, especially a kind of CO 2Wire feeding motor speed governing of/MAG/MIG arc welder and control supply unit.
Background technology
All kinds of CO of thyristor type or contravariant 2The various carbon steels of/MAG/MIG gas shielded arc welding machine extensive use, stainless steel, aluminium, metal welded and high efficient such as magnesium.CO 2/ MAG/MIG welding method passes to CO usually 2Gas, CO 2+ Ar mist, gases such as Ar gas are protective gas, electric arc comes the deposite metal between dependence welding wire and the weldment, is a kind of energy-efficient welding method.Usually source of welding current employing thyristor type rectification control or IGBT or field effect transistor contravariant power are constant pressure source, are equipped with the automatic feeding device again, and wire feeding motor is sent welding wire automatically, and energy that soldered power supply provides fusing forms welding arc.All kinds of gas shielded arc welding machine need of work control circuits need to supply with D.C. regulated power supply, and in addition, the automatic feeding of welding machine adopts the speed governing of direct current printed motor.All kinds of in the past CO 2The speed governing of/MAG/MIG arc welder automatic feeding reaches will use the power frequency control transformer for it provides the supply unit of control circuit, and power is about 250W usually.
Summary of the invention
The objective of the invention is to overcome the deficiencies in the prior art, a kind of CO that does not have the power frequency control transformer is provided 2Wire feeding motor speed governing of/MAG/MIG arc welder and control supply unit.
According to technical scheme provided by the invention, described CO 2Reach MAG and the wire feeding motor speed governing of MIG arc welder and control supply unit and comprise: pulse width modulating chip LT1247,6 pin of pulse width modulating chip LT1247 connect fet gate by the 5th resistance; The field effect transistor source electrode is by the 4th grounding through resistance, drain electrode connects an end of elementary second winding of switch transformer, and be connected the other end of elementary second winding of switch transformer successively with the parallel circuits of second electric capacity by second diode, the 15 resistance, the other end of elementary second winding of switch transformer connect simultaneously the arc welder major loop+the 540V power supply; The arc welder major loop+the 540V power supply connects the negative electrode of first diode successively by first resistance and second resistance, first diode cathode is by first capacity earth, anode connects an end of elementary first winding of switch transformer, the elementary first winding other end ground connection of switch transformer; Node between first resistance and second resistance connects 7 pin of pulse width modulating chip LT1247, and connect 2 pin of pulse width modulating chip LT1247 by the 9th resistance, the parallel circuits that connects the 6th resistance and the 4th electric capacity between 2 pin of pulse width modulating chip LT1247 and 1 pin simultaneously 2 pin of pulse width modulating chip LT1247 by the 7th grounding through resistance; 8 pin of pulse width modulating chip LT1247 connect 4 pin of pulse width modulating chip LT1247 simultaneously by the 5th capacity earth by the 8th electric capacity, 4 pin of pulse width modulating chip LT1247 are by the 3rd capacity earth; 3 pin of pulse width modulating chip LT1247 connect the field effect transistor source electrode by the tenth resistance; One end of secondary first winding of switch transformer connects the Vi end of three-terminal voltage regulator LM338 by first diode, the anode of the V0 termination wire feed printed motor of three-terminal voltage regulator LM338, the stiff end of the Aaj termination potentiometer of three-terminal voltage regulator LM338, the negative terminal of the adjustable termination wire feed printed motor of potentiometer also connects the other end of secondary first winding of switch transformer, connects the 11 resistance between the V0 end of three-terminal voltage regulator LM338 and the Aaj end; One end of secondary second winding of switch transformer connects first output port by the 4th diode, another termination second output port of secondary second winding of switch transformer, one end of the secondary tertiary winding of switch transformer connects the 3rd output port by the 5th diode, another termination the 4th output port of the secondary tertiary winding of switch transformer; Connect the 6th electric capacity between the two ends of secondary second winding of switch transformer, connect the 7th electric capacity between the two ends of the secondary tertiary winding of switch transformer.
Present invention includes by pulse width modulating chip LT1247 and field effect transistor and switch transformer and form Switching Power Supply, the alignment circuit of forming by three-terminal voltage regulator LM338, external potentiometer, and the secondary two groups of power supplies of switch transformer.
Advantage of the present invention is: apparatus of the present invention have been saved conventional power frequency control transformer, wire feeding motor alignment circuit and control supply unit have been simplified, adopt pulse width modulating chip LT1247 add adjustable circuit of three-terminal voltage-stabilizing integrated LM338 etc. form a kind of switching power unit, realize all kinds of CO 2The speed governing of/MAG/MIG arc welder wire feed printed motor (the printed motor operating voltage range be DC1.25 ~ 25V) and control circuit required ± power supply of 15V power supply; Reduce all kinds of CO 2/ MAG/MIG arc welder cost, especially saving the power frequency control transformer, more to adapt to contravariant welding machine volume little, in light weight, energy-efficient characteristics.
Description of drawings
Fig. 1 is contravariant CO 2/ MAG/MIG arc welder major loop and this device connection diagram.
Fig. 2 is thyristor type or other control method CO 2/ MAG/MIG arc welder major loop and this device connection diagram.
Fig. 3 is the CO that the present invention does not have the power frequency control transformer 2Wire feeding motor speed governing of/MAG/MIG arc welder and control circuit device circuit theory diagrams.
Embodiment
The invention will be further described below in conjunction with drawings and Examples.
Fig. 1 is all kinds of contravariant CO 2/ MAG/MIG arc welder main circuit, normally line voltage → directly rectification → filtering → high-frequency inversion → secondary rectification → direct current output waits each link.Adopting inversion circuit can be inversion links such as IGBT or field effect transistor.The DC540V voltage that the patent device input voltage is directly taken from behind rectifying and wave-filtering of major loop links to each other with this device through plug CN1.
Fig. 2 is thyristor type or other control mode CO 2/ MAG/MIG arc welder major loop, normally line voltage → power frequency step-down transformer step-down → silicon con trolled rectifier → direct current is exported each link.Patent device increases a three-phase commutation bridge QD and capacitor C filtering obtains DC540V voltage, links to each other with this device through plug CN1.
As shown in Figure 3, the CO of no power frequency control transformer of the present invention 2The Switching Power Supply that/MAG/MIG arc welder wire feeding motor alignment circuit and control supply unit adopt up-to-date pulse width modulating chip LT1247 and accessory circuit thereof to form, form N1 level first winding (5 ~ No. 6) and produce the 28V high-frequency ac, through diode D3 rectification and three-terminal voltage regulator LM338, required DC 1.25 ~ 25 voltages of output feed silk-screen brush motor M, the control current of electric can reach more than the 3A.Two windings of N1 level second, third winding (7 ~ 8,9 ~ No. 10) form two groups of D.C. regulated power supplies behind rectifying and wave-filtering, be ± 15V that electric current is about 1A for control circuit usually.The concrete annexation of circuit is: 6 pin of pulse width modulating chip IC1 (LT1247) connect field effect transistor Q1 grid by the 5th resistance R 5; Field effect transistor Q1 source electrode is by the 4th resistance R 4 ground connection, drain electrode connects an end of elementary second winding of switch transformer N1, and be connected the other end of elementary second winding of switch transformer N1 successively with the parallel circuits of second capacitor C 2 by the second diode D2, the 15 resistance R 15, the other end of elementary second winding of switch transformer N1 connect simultaneously the arc welder major loop+the 540V power supply; The arc welder major loop+the 540V power supply connects the negative electrode of the first diode D1 successively by first resistance R 1 and second resistance R 2, the first diode D1 negative electrode is by first capacitor C, 1 ground connection, anode connects an end of elementary first winding of switch transformer N1, the elementary first winding other end ground connection of switch transformer N1; Node between first resistance R 1 and second resistance R 2 connects 7 pin of pulse width modulating chip IC1, and connect 2 pin of pulse width modulating chip IC1 by the 9th resistance R 9, the parallel circuits that connects the 6th resistance R 6 and the 4th capacitor C 4 between 2 pin of pulse width modulating chip IC1 and 1 pin simultaneously 2 pin of pulse width modulating chip IC1 by the 7th resistance R 7 ground connection; 8 pin of pulse width modulating chip IC1 connect 4 pin of pulse width modulating chip IC1 simultaneously by the 5th capacitor C 5 ground connection by the 8th electric capacity R8,4 pin of pulse width modulating chip IC1 are by the 3rd capacitor C 3 ground connection; 3 pin of pulse width modulating chip IC1 connect field effect transistor Q1 source electrode by the tenth resistance R 10; One end of N1 level of switch transformer first winding connects the Vi end of three-terminal voltage regulator W1 (LM338) by the first diode D1, the anode of the V0 termination wire feed printed motor M of three-terminal voltage regulator W1, the stiff end of the Aaj termination potentiometer VR of three-terminal voltage regulator W1, the negative terminal of the adjustable termination wire feed printed motor M of potentiometer VR also connects the other end of switch transformer N1 time level first winding, connects the 11 resistance R 11 between the V0 end of three-terminal voltage regulator W1 and the Aaj end; One end of N1 level of switch transformer second winding connects first output port by the 4th diode D4, another termination second output port of N1 level of switch transformer second winding, one end of N1 level of the switch transformer tertiary winding connects the 3rd output port by the 5th diode D5, another termination the 4th output port of N1 level of the switch transformer tertiary winding; Connect the 6th capacitor C 6 between the two ends of N1 level of switch transformer second winding, connect the 7th capacitor C 7 between the two ends of N1 level of the switch transformer tertiary winding.
DC 540V voltage from Fig. 1 or circuit shown in Figure 2 output, through plug CN1 input, through R1 and R9, the bleeder circuit of R7 is supplied with the voltage of pulse width modulating chip IC1 (LT1247) greater than 16V, chip is started working, and 6 pin output amplitudes are the 12V pulse, drives field effect transistor Q1 conducting through R5, this moment, power supply was given elementary second winding of switch transformer N1 (3 ~ No. 4) charging, and electric energy is converted to magnetic energy and is stored in the switch transformer.And the conducting of field effect transistor Q1 with end, 4 pin pulse frequencies by chip IC 1 determine that (pulse frequency is by the R8 of 4 pin, the C3 decision), when first pulse high level finishes, transfer low level to, make Q1 end, at elementary second winding of N1 (3 ~ No. 4) induced electromotive force is last negative timing down, and elementary first winding (1 ~ No. 2) of N1 then induced electromotive force direction is last negative just down, diode D1 conducting, to the C1 charging, supply with chip IC 1 supply voltage.The internal error amplifier of chip IC 1 is by R6, and C4 inserts the PI controlling unit.The output current of Q1 is fed back through R4, and 3 pin and the internal error amplifier that enter chip IC 1 through R10 compare, and guarantee that the 6 pin output of chip IC 1 is stable.
The Switching Power Supply of being formed by chip IC 1, secondary first winding (5 ~ No. 6) the output 28V high-frequency ac of switch transformer N1, through the D3 rectification, pass through three-terminal voltage regulator W1 (LM338) output DC 1.25V ~ 25V direct voltage again, the work of feed silk-screen brush motor M (generally adopt rated operational voltage DC 24V printed motor, operating voltage range DC1.25V ~ 25V).By changing motor operating voltage, promptly changed rotating speed of motor, for all kinds of CO 2/ MAG/MIG arc welder automatic feeding.The operating voltage adjustable range of motor is by external potentiometer VR and R11 decision.
The Switching Power Supply of being formed by chip IC 1, secondary second winding (7 ~ No. 8) and the tertiary winding (9 ~ No. 10) of switch transformer N1 are output as the 17V high-frequency ac, pass through D4 then, D5 rectification and C6, C7 filtering forms two groups of DC power supply, and being generally dc voltage is 15V, about DC electric current 1A, for all kinds of CO 2/ MAG/MIG arc welder control circuit power supply ± 15V work.
This patent changes traditional wire feeding motor speed regulating method, and traditional speed regulating method generally adopts the power frequency control transformer, cooperates the thyristor speed control circuit to realize the wire feeding motor speed governing.The present invention mainly is to have saved conventional power frequency control transformer, adopts circuit such as Switching Power Supply and three-terminal voltage regulator to realize all kinds of CO 2Wire feed printed motor operating voltage range 1.25V ~ 25VDC is satisfied in the speed governing of/MAG/MIG arc welder wire feeding motor, the requirement that operating current 3A is above.The Switching Power Supply of this patent formation also can be all kinds of CO simultaneously 2/ MAG/MIG arc welder control circuit provides power supply, is generally DC ± 15V, and the 1A output current has saved traditional circuit such as power frequency control transformer step-down rectifier filtering voltage regulation.A kind of CO that does not have the power frequency control transformer 2/ MAG/MIG arc welder wire feed alignment circuit and control supply unit are as the arc welder self-contained unit.The input voltage of device is to contravariant CO 2/ MAG/MIG arc welder can directly be taken from the DC540V power supply behind the 3 phase power supply rectification filters, to thyristor type or other form control CO 2/ MAG/MIG arc welder, this device only increase a three-phase commutation bridge and capacitor filtering and obtain the DC540V power supply, and be easy to connect.
Device circuit shown in Figure 3 is simple in structure, and used components and parts are few, the reliability height, and the materials cost is low, has saved power frequency control transformer in the past, because of general power frequency control transformer power is about about 250W.And this device is except that possessing above advantage, and main is efficient energy-saving, and volume is little, and is in light weight, can be applicable to thyristor type and all kinds of CO 2/ MAG/MIG arc welder more is applicable to contravariant CO 2/ MAG/MIG arc welder.

Claims (1)

1. CO 2And MAG and the wire feeding motor speed governing of MIG arc welder and control supply unit, it is characterized in that: comprise pulse width modulating chip LT1247(IC1), pulse width modulating chip LT1247(IC1) 6 pin connect field effect transistor (Q1) grid by the 5th resistance (R5); Field effect transistor (Q1) source electrode is by the 4th resistance (R4) ground connection, drain electrode connects an end of elementary second winding of switch transformer (N1), and be connected the other end of elementary second winding of switch transformer (N1) successively with the parallel circuits of second electric capacity (C2) by second diode (D2), the 15 resistance (R15), the other end of elementary second winding of switch transformer (N1) connect simultaneously the arc welder major loop+the 540V power supply; The arc welder major loop+the 540V power supply connects the negative electrode of first diode (D1) successively by first resistance (R1) and second resistance (R2), first diode (D1) negative electrode is by first electric capacity (C1) ground connection, anode connects an end of elementary first winding of switch transformer (N1), the elementary first winding other end ground connection of switch transformer (N1); Node between first resistance (R1) and second resistance (R2) meets pulse width modulating chip LT1247(IC1) 7 pin, and meet pulse width modulating chip LT1247(IC1 by the 9th resistance (R9)) 2 pin, pulse width modulating chip LT1247(IC1) 2 pin and 1 pin between connect the 6th resistance (R6) and the 4th electric capacity (C4) parallel circuits pulse width modulating chip LT1247(IC1 simultaneously) 2 pin by the 7th resistance (R7) ground connection; Pulse width modulating chip LT1247(IC1) 8 pin meet pulse width modulating chip LT1247(IC1 by the 8th electric capacity (R8) simultaneously by the 5th electric capacity (C5) ground connection) 4 pin, pulse width modulating chip LT1247(IC1) 4 pin by the 3rd electric capacity (C3) ground connection; Pulse width modulating chip LT1247(IC1) 3 pin connect field effect transistor (Q1) source electrode by the tenth resistance (R10); One end of secondary first winding of switch transformer (N1) meets three-terminal voltage regulator LM338(W1 by first diode (D1)) Vi end, three-terminal voltage regulator LM338(W1) anode of V0 termination wire feed printed motor (M), three-terminal voltage regulator LM338(W1) stiff end of Aaj termination potentiometer (VR), the negative terminal of the adjustable termination wire feed printed motor (M) of potentiometer (VR) also connects the other end of secondary first winding of switch transformer (N1), three-terminal voltage regulator LM338(W1) connect the 11 resistance (R11) between V0 end and the Aaj end; One end of secondary second winding of switch transformer (N1) connects first output port by the 4th diode (D4), another termination second output port of secondary second winding of switch transformer (N1), one end of the secondary tertiary winding of switch transformer (N1) connects the 3rd output port by the 5th diode (D5), another termination the 4th output port of the secondary tertiary winding of switch transformer (N1); Connect the 6th electric capacity (C6) between the two ends of secondary second winding of switch transformer (N1), connect the 7th electric capacity (C7) between the two ends of the secondary tertiary winding of switch transformer (N1).
CN2011100843935A 2011-04-02 2011-04-02 Speed regulating and power controlling device of wire feed motor of CO2/MAG (metal active gas)/MIG (metal insert gas) arc welding machine Pending CN102148600A (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2430811Y (en) * 2000-06-17 2001-05-16 汕头经济特区自动化电器设备总厂有限公司 High frequency switch DC voltage-stablized source with multiway output
CN201239844Y (en) * 2008-04-23 2009-05-20 蒋仲湘 Novel soft switch inversion type carbon dioxide gas protecting welder
CN202009358U (en) * 2011-04-02 2011-10-12 无锡市南方电器制造有限公司 Stick-feeding motor speed regulation and control power supply device for CO2/MAG/MIG arc welding machines

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2430811Y (en) * 2000-06-17 2001-05-16 汕头经济特区自动化电器设备总厂有限公司 High frequency switch DC voltage-stablized source with multiway output
CN201239844Y (en) * 2008-04-23 2009-05-20 蒋仲湘 Novel soft switch inversion type carbon dioxide gas protecting welder
CN202009358U (en) * 2011-04-02 2011-10-12 无锡市南方电器制造有限公司 Stick-feeding motor speed regulation and control power supply device for CO2/MAG/MIG arc welding machines

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
李秀涛: "《电流控制型PWM控制芯片LT1247在电动汽车逆变器开关电源中的应用》", 《变流技术与电力牵引》 *

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Application publication date: 20110810