CN2474261Y - D.C. tungsten electrode argon arc welding machine program control and high frequency arc striking circuit - Google Patents

Abstract

The utility model relates to a process controlling for a direct current argon tungsten-arc welding machine and a high frequency arc-striking circuit, comprising a process controlling circuit and the high frequency arc-striking circuit. The utility model is characterized in that the designed process controlling circuit is used for transmitting air, high-frequency arc-striking, welding, cutting sown high frequency, terminating the welding, hysteresis finishing air and cutting arc, which can totally satisfy the demand of process controlling circuit to the tungsten-arc welding machine. The high frequency arc-striking circuit utilizes a high-frequency potential transformer to replace an original low-frequency or intermediate-frequency potential transformer, and thereby the replacement of the conventional working means by a working means of multi-cycle energy storage of a capacitance is realized. The conventional working means is that a secondary high frequency vibrates at a time by each actjvation of a primary high frequency. The utility model has the advantages of convenient parameter adjustment, high efficiency, stable working condition, small high-frequency interference, easy arc-striking, reliability and convenient utilization.

Description

Welding machine programme-control of direct current tungsten argon arc and high-frequency arc ignition circuit

The utility model is a kind of programme-control and high-frequency arc ignition circuit of direct current tungsten argon arc welding machine, and it not only is applicable to direct tungsten argon arc welding machine, equally also practical air plasma cutter.

At present, argon arc welding machine sequence circuit and high-frequency arc ignition circuit still adopt this hf arc starter of the direct boost type higher-order of oscillation of power frequency, and volume is big, make difficulty, adopt controllable silicon medium-frequency oscillator boosting mode, and frequency is the highest also can only to reach 3KHz.The utility model has adopted FET to make the high-frequency arc strike oscillator, and frequency of oscillation is 20KHz, and it is little, in light weight to have a volume, efficient height, characteristics such as high frequency output is stable, and striking is reliable.

Program system control circuit of the present utility model, the sequential chart of its welding such as Fig. 2, its circuit theory diagrams such as Fig. 3.Programme-control and high-frequency arc strike are the important component parts that argon arc welding machine is realized the welding process automation.Institute has programme controlled sequential function and is: A, send argon gas in advance, promptly ought press weldering and rob control at the first bruss, argon gas can flow out from torch neck immediately, postpones to restart the source of welding current after a period of time, be called the striking time during this period of time, general requirement is adjustable continuously in second at 1-3.B, puncture the air gap between welding gun electrode and the welded piece, realize the noncontact striking with high-frequency and high-voltage.In case promptly the source of welding current is unlocked, can produce high-frequency and high-voltage at once.C, successful as if high-frequency arc strike, the source of welding current welds normally, at this moment, will excise high-frequency and high-voltage immediately.D, after finishing welding, a period of time is closed argon gas in time-delay, with protection tungsten electrode and molten bath.Claim gas lag time during this period of time, general require adjustable continuously in second at 3-14.E, after stopping welding, as long as argon gas is not closed, promptly gas does not finish lag time, if need press the control beginning on the welding gun again, will start the source of welding current immediately, does not need the striking time.This sequence circuit, multiple functional, satisfy argon arc welding machine fully to programme controlled requirement.

High-frequency arc ignition circuit of the present utility model such as Fig. 4, B ₂Be high frequency transformer, adopt 14 cun black and white television set line output transformers and power beginning pipe V ₁Form the single-ended flyback inverter circuit, forms multivibrator by 555, in the generation high-frequency drive arteries and veins, getting frequency of oscillation is 20KHz, the single-ended flyback inverter is reverse into the high frequency of 20KHz with low frequency, and (about 90V) is reverse into nearly 3000V high-frequency high-voltage with low-voltage, to capacitor C ₈Charging, the disruptive spark plug, the output output higher-order of oscillation striking voltage to the source of welding current carries out the argon arc welding.

The utility model direct current tungsten argon arc welding machine sequence circuit and high-frequency arc ignition circuit, multiple functional, it is little to have volume, in light weight, and cost is low, striking is fast and reliable, precise control, characteristics such as High-frequency Interference is little, and is easy to use, it not only is applicable to direct current tungsten argon arc welding machine, and is applicable to air plasma cutter.

Below in conjunction with drawings and Examples utility model is further specified:

Fig. 1: be functional-block diagram of the present utility model

Fig. 2: be argon arc welding SECO figure of the present utility model

Fig. 3: be argon arc welding cyclematics of the present utility model

Fig. 4: be the utility model argon arc welding high-frequency arc ignition circuit figure

As shown in Figure 1, for functional-block diagram of the present utility model, by the source of welding current, sequence circuit figure, high-frequency arc ignition circuit figure forms.

As shown in Figure 2, for the utility model argon arc welding SECO figure, by the sequential of argon gas, the sequential of high-frequency arc strike and the compositions such as sequential of welding current.

As shown in Figure 3, be the utility model argon arc welding sequence circuit figure, it is to realize the SECO function that argon arc welds and the sequence circuit figure that designs.K is the welding gun gauge tap among the sequence circuit figure, and when pressing weldering when robbing control beginning K, supply voltage+Vc passes through D ₁₆Be added to relay J immediately ₃Control end, its output gets electric, contact J ₃-1 closure, magnetic valve gets electric, opens air valve, and argon gas sprays from torch neck immediately.Simultaneously, supply voltage+Vc passes through resistance R ₁₀, diode D ₁₈, potentiometer W ₃And resistance R ₁₂To capacitor C ₂₂Charging makes capacitor C ₂₂Current potential raises, and when the current potential of operational amplifier pin 10 is higher than giving of operational amplifier pin 9 and puts current potential, makes the current potential upset of operational amplifier pin 8, changes positive potential into from negative voltage, triode V ₅, V ₆Conducting makes relay J ₁Control end get electric, contact J ₁-1, J ₁-2, J ₁-3 closures, at this moment, supply voltage+Vc passes through D ₂₂Be added to relay J ₅Control end, contact J ₅-1 closure is opened the source of welding current, as seen, regulates W ₃, the length that can regulate the striking time claims to be during this period of time the striking time, general requirement is adjustable continuously in second at 1-3.Since the startup of the source of welding current, sample resistance R ₁₆, R ₁₇Mid point raise with the foundation of floating voltage, when the current potential of the in-phase end pin 5 of operational amplifier IC4-2 was higher than the current potential of out-phase end pin 6, the current potential of output pin 7 is upset immediately just, changes positive potential into from negative potential, makes triode V ₃, V ₄Conducting, supply voltage+Vc is by triode V ₄Be added to relay J ₂Control end, make contact J ₂-1 closure.Supply voltage+Vc is by diode D ₁₇, J ₂-1, be added to relay J ₄Control end, make contact J ₄-1 closure is connected the high-frequency arc ignition circuit input, produces high-frequency and high-voltage immediately, and high-frequency and high-voltage is by high-frequency arc strike coupling transformer B ₃Secondary is coupled to welding in the mode of series connection and goes the same way, when the gap between welding gun electrode and the workpiece is breakdown, and the high-frequency arc strike success, in case the high-frequency arc strike success, source of welding current output voltage descends immediately, sampling electricity group R ₁₆, R ₁₇The voltage of mid point B descends immediately, and when the current potential of the in-phase end pin 5 of operational amplifier IC4-1 dropped to the current potential that is lower than end of oppisite phase pin 6, the current potential of its output pin 7 was turned to negative potential immediately from positive potential, thereby makes triode V ₃, V ₄End the control end dead electricity of relay J 2, contact J ₂-1 opens, relay J ₄Dead electricity makes contact J ₄-1 opens, and high-frequency arc ignition circuit quits work, and the source of welding current carries out normal welding job, after finishing welding, when unclamping welding during gauge tap, this moment D ₁₆End relay J ₃Continue conducting, magnetic valve still electric, argon gas continues to flow out from torch neck, protecting the molten bath, and capacitor C ₂₂To pass through J ₁-2, R ₁₁, W ₂, R ₁₀, R ₉Discharge, its discharge time constant is about t ₁=(R ₁₁+ R ₁₀+ R ₉+ W ₂) C ₂₂, along with C ₂₂The carrying out of discharge, the voltage at its two ends descends gradually, and simultaneously, supply voltage+Vc passes through R ₁₃, D ₁₉To C ₂₂Charging, its charge constant is t ₂=R ₁₃C ₂₂, still, R ₁₃＞＞(R ₁₁+ R ₁₀+ R ₉+ W ₂), so charge effects can be ignored, when the current potential of operational amplifier IC4-3 pin 10 hanged down the current potential of pin 9, the current potential of its output pin 8 overturn immediately, is negative potential from the positive potential saltus step, triode V ₅, V ₆End relay J ₁Dead electricity, contact J ₁-1, J ₁-2, J ₁-3 disconnect, at this moment, and C ₂₂Both end voltage is passed through D ₁₅, R ₈Discharge decays to zero, relay J rapidly ₃Dead electricity, contact J ₃-1 disconnects, and magnetic valve DF dead electricity is closed argon gas, as seen, regulates W ₂, can change lag time of argon gas, claim be argon gas lag time during this period of time, general requirement is adjustable continuously in second at 3-14.

In sum, the function that this sequence circuit is realized satisfies the programme controlled requirement of argon arc welding machine to high-frequency arc strike fully.

As shown in Figure 4, be the utility model high-frequency arc ignition circuit, it is by high frequency pulse generator, the single-ended flyback inverter, and high-frequency oscillating circuits and high-frequency arc strike lotus root are closed follower and form.With 555 composition multivibrators, produce the high-frequency drive pulse, getting frequency of oscillation is 20KHz, adds guiding diode D ₇, D ₈, its charge and discharge time constant can be regulated separately.The sine wave alternating current of 90V is through rectifying tube D ₁-D ₄Rectification is through capacitor C ₁, C ₂With R ₁The Lu wave circuit of forming becomes direct current, joins by high-tension transformer B ₂With power switch pipe V ₁The single-ended flyback inverter B that forms ₂High-tension transformer adopts 14 cun black and white television set line output transformers.High-voltage capacitance C ₈, the elementary composition high-frequency oscillating circuits of spark plug and higher-order of oscillation follower B3.Single-ended flyback inverter B ₂The high-frequency and high-voltage of the nearly 3000V of secondary output, to capacitor C ₈Charge, make the voltage U c at C two ends ₈Raise V ₁Constantly trigger C ₈Constantly power storage is worked as UC ₈After reaching disruptive spark plug voltage U p, the breakdown short circuit of spark plug, radio circuit C ₈, L ₂Resonance takes place, promptly produce the higher-order of oscillation, frequency of oscillation is: $\mathrm{fo}=\frac{1}{2\mathrm{\&pi;}}\sqrt{\frac{1}{{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="Y0121349300101.png"\; state="\{\{state\}\}">L</figure-callout>}}_2\&CenterDot;{\mathrm{<figure-callout\; id="8"\; label="C"\; filenames="Y0121349300101.png"\; state="\{\{state\}\}">C</figure-callout>}}_8}\&CenterDot;\frac{{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="Y0121349300101.png"\; state="\{\{state\}\}">R</figure-callout>}}^2}{4{\mathrm{<figure-callout\; id="2"\; label="L"\; filenames="Y0121349300101.png"\; state="\{\{state\}\}">L</figure-callout>}}_2^2}}$ Scheme the time attenuation constant of the bright oscillating voltage of attached book: $T=\frac{2L_2}{R}$

Work as capacitor C ₈When both end voltage decayed to smaller value, SD recovered blocking ability, C ₈Again be recharged again, SD is breakdown again, begins a new cycle of oscillation again.

Higher-order of oscillation follower B ₃High-frequency oscillation voltage U on the former limit _L2Be coupled to during welding goes the same way with series system by paying the limit, this voltage is added in the going the same way that welding gun electrode and workpiece gap form, and when the gap between welding gun electrode and the workpiece was punctured by high-frequency and high-voltage, high-frequency arc strike successfully.

The small-sized hf arc starter of this kind has two outstanding features: 1. with high frequency power transformer substituted low frequency or Middle frequency power transformer because the raising of frequency has reduced cost, has reduced volume, 2. deposits with the electric capacity multicycle The working method of energy storage has replaced traditional elementary every triggering once, worker who closes together of secondary high frequency vibration Make mode, this kind working method has been brought convenience to parameter adjustment, makes striking fast and reliable, precise control, The characteristics such as the High-frequency Interference that produces is little, it not only is applicable to direct-flow argon-arc welder, be suitable for equally air etc. from Sub-cutting machine.

Claims (3)

1, the utility model is welding machine programme-control of direct current tungsten argon arc and high-frequency arc ignition circuit.It is characterized in that it is made up of sequence circuit and high-frequency arc ignition circuit.

2, according to claim 1, described novel argon arc welding machine sequence circuit, it is by K switch, relay J ₁, J ₂, J ₃, J ₄, J ₅, diode D ₁₄, D ₁₅, D ₁₆, D ₁₇, D ₁₈, D ₁₉, D ₂₀, D ₂₁, D ₂₂, D ₂₃, triode V ₃, V ₄, V ₅, V ₆, adjustable potentiometer W ₂, W ₃, W ₄, W ₅, resistance R ₈, R ₉, R ₁₀, R ₁₁, R ₁₂, R ₁₃, R ₁₄, R ₁₆, R ₁₇, R ₁₈, R ₁₉, R ₂₀, R ₂₁, R ₂₂, R ₂₃, R ₂₄, R ₂₅, R ₂₆, R ₂₇, R ₂₈, R ₂₉, R ₃₀, R ₃₁Capacitor C ₂₁, C ₂₂, operational amplifier IC4-1, IC4-2, IC4-3, IC4-4 and magnetic valve DF form.Above-mentioned device is pressed Fig. 3, links to each other one by one, forms argon arc welding machine sequence circuit figure.

3, according to claim 1, described novel argon arc welding machine high-frequency arc ignition circuit, it is by high frequency transformer B ₂, high-frequency arc strike coupling transformer B ₃, device IC1, relay J ₄Contact J ₄-1, diode D ₁, D ₂, D ₃, D ₄, D ₅, D ₆, D ₇, D ₈, D ₂₃, triode V ₂, V ₁, FET V ₁, capacitor C ₁, C ₂, C ₄, C ₃, C ₅, C ₂₃, C ₈, potentiometer W ₁, electricity group R ₂, R ₃, R ₄, R ₅, R ₆, R ₇, relay J ₄Contact J ₄-1, compositions such as spark plug FD.Above-mentioned electronic devices and components are pressed Fig. 4, link to each other one by one, form high-frequency arc ignition circuit figure.

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