CN85109183A - Electric welding machine - Google Patents

Abstract

The present invention is by adopting the welding current detection signal that whether welding current is arranged to detect, add that the short circuit of removing welding wire and soldered thing contact and transfer to the short-circuit detection signal that non-contacting state detects to be used as sending the starting the arc and the high pressure starting the arc to transfer the triggering signal of stablize welding condition to slowly from welding wire, thereby the electric welding machine with even, reliable arc starting performance is provided.

Description

Electric welding machine

The present invention is the welding wire of relevant automatic transport as consumable electrode, makes it to produce the electric welding machine that electric arc welds.

The originally control when the starting the arc, carried out of this class electric welding machine, be to adopt the welding wire of when the starting the arc, wire feed rate being reduced to the value when being lower than stable the welding to send starting the arc method slowly, reach the high pressure starting the arc method that when the starting the arc, output voltage is increased to the value when being higher than stable the welding, this is well-known, and the triggering signal that is converted to stable state as the state that send the starting the arc and the high pressure starting the arc from these welding wires slowly just relies on detection to have or not the welding current detection signal of welding current.

Original method can not be absorbed in when beginning to weld because the time difference that differences such as welding wire end shape produce electric arc, the result will produce that welding wire ruptures midway and phenomenon such as the welding wire that burns during excessive starting and fail to obtain uniform arc starting performance.Also have, method originally also will make welding wire send arc condition and high pressure to play arc condition slowly for different gage of wires and solder wire material and play corresponding variation, will change simultaneously to turn to deal with the conversion time of stablizing welding condition.Even done such processing, particularly resembling the aluminium wire owing to the very low situation that is difficult for heat fused of intrinsic resistivity, also fail to obtain uniform arc starting performance, welding wire is continuing the semi-molten state, and do not produce electric arc, the result adds the accident that will produce the welding wire of buckling too energetically in welding wire, or burns when sending explosive sound because of welding wire is excessive, and the molten problems such as accident that stick at the energising tip of filler wire take place.

The objective of the invention is to provide a kind of electric welding machine, this electric welding machine has to detect by employing and does not have as from sending the starting the arc and the high pressure starting the arc welding current detecting signal to the welding current of stablize triggering signal that welding condition changes slowly, and after the short circuit contact is disengaged generation electric arc between welding wire and the soldered thing, differentiate weldingvoltage and whether reached the above short circuit detecting signal of certain value, to reach evenly arc starting performance reliably.

In order to reach above-mentioned purpose, the present invention has the welding current testing circuit whether judgement has welding current and output detection signal, with judge welding wire be with soldered thing contact short circuit or the noncontact welding wire short-circuit signal testing circuit of output signal then, and with each output signal of above-mentioned welding current testing circuit and welding wire short-circuit detecting circuit as input, the output control circuit that the control element and the welding wire of control bonding power transmitted motor output control signal then.Above-mentioned output control circuit such as Fig. 1 constitute, promptly when beginning to weld the starting the arc, the output signal of above-mentioned welding current testing circuit is the state that welding current is arranged, and the output signal of above-mentioned welding wire short-circuit detecting circuit is after the both sides that are in non-contacting state with soldered thing detect, just export the output signal of conversion and control wire feeding motor, make the low velocity so-called welding wire slow-motion starting the arc speed of wire feed rate when being lower than stable welding become the speed of stable welding, export the output signal of conversion and control bonding power control element simultaneously, the high power (hot start power) when making bonding power stablize welding from being higher than transfers stable bonding power to.

Whether whether the welding current testing circuit 14 among Fig. 1 is the welding current signal of amplifying current divider 6, reach more than the certain value with this value, to having welding current to judge and being defeated by output control circuit 13 as a-signal.Welding wire electric circuit inspection circuit 15 is whether to reach certain value with output voltage values whether to touch soldered thing 10 with the butt welding silk 9 that comes up and judge, and is defeated by output control circuit 13 as the S signal.Output power controlling circuit 13 is when beginning to weld the starting the arc, welding wire 9 is connected welding current once touching soldered thing 10, even above-mentioned a-signal is in the state that welding current is arranged, welding 9 also touches soldered thing 10 and output voltage values is also low, if above-mentioned S signal is to be judged as contact short circuit, the index signal V of the high power (hot start power) when just 4 outputs are higher than stable welding to the welding power control member, the index signal M of the rotation (welding wire send starting the arc rotation slowly) when 12 outputs are lower than stable welding to wire feeding motor simultaneously.Welding wire top-produce electric arc through heating, above-mentioned a-signal continues to maintain the state of welding current, above-mentioned S signal then transfers non-contacting state to, output control circuit 13 detects this variation, just send by the hot start power transfer to stablize the index signal V of bonding power, send the index signal M that send the starting the arc to transfer to stablize the rotation when welding by welding wire slowly to wire feeding motor 12 simultaneously to bonding power control element 4.In addition, 1 among Fig. 1 is input end of electric welding machine, the 2nd, and the transformer of welding usefulness, the 3rd, rectification, smoothing circuit portion, the 5th, reactor circuit portion, the 7th, electric welding machine output, the 8th, the ignition tip of energising usefulness, the 11st, welding arc portion.

Time of the various signals among Fig. 1 when the starting the arc changes as shown in Figure 2, and is identical with Fig. 1 and above-mentioned explanation about the explanation of the definition of A, the S of Fig. 2, M, V signal and work.

Compare with the original technology feature that had and positive effect of the present invention is:

1. eliminated arc failure, reliable arc starting performance has been arranged.

2. touch the time that produces electric arc when longer from welding wire, the sensation that can not give collision to the operator.

3. when beginning to weld, can both obtain uniform arc starting performance for the welding wire top of Any shape.Particularly for the soft welding wire of picture aluminium wire and so on, can prevent owing to buckle thing and excessive triggering of welding wire burnt and caused the molten generation that sticks at the accident of ignition tip of welding wire.

The description of the drawings

Fig. 1 is the calcspar of expression configuration example of the present invention, and Fig. 2 is the signal waveforms of the course of work of expression each signal at Fig. 1 of the present invention, and Fig. 3 is the flow chart of the program when having used microcomputer in the output control circuit portion of the embodiment of the invention.The detection whether welding current is arranged is with the input amplification from the current divider 6 of Fig. 1, and then compares more than the value that reaches certain whether.The detection whether welding wire contacts also is to check the electric welding machine output voltage, and relatively whether this value has reached more than the certain value, contacts then or non-contacting judgement.These testing circuits also have hysteresis characteristic to prevent vibration and faulty operation.Also have, also will have some time limits seven d that delay to transferring to the stable condition output from time seven of Fig. 2, to guarantee making welding wire completing combustion in operation.And should the processing of time limits seven d on program, because flow chart is very numerous and diverse, so in the flow chart of Fig. 3, omitted.

In addition, Fig. 3 is in embodiments of the present invention, the program flow diagram when the output control circuit 13 of Fig. 1 has used microcomputer.Do not have one " in the starting the arc? " among the figure determining step, even be, can not return high electric current for welding wire in stable welding touches soldered thing yet, welding wire send the condition of the starting the arc slowly.Particularly stablize welding and be not welding to spray transfer, in the welding of MIG, MAG, CO, owing to be the state of making often to repeat welding wire and soldered thing contact circuit and the welding of the state of noncontact generation electric arc, so that this step must not practised especially is few to circuit transition.In addition, be somebody's turn to do " in the starting the arc? " the flow chart of determining program also for fear of complicated, and in Fig. 3, omitted detailed description, but in force, whether at first pick up counting after stablizing welding condition from exporting, be to reach to come before or after the certain value to judge in the starting the arc with this timing numerical value.Also be designed to not being judged as short circuit simultaneously at common short circuit duration during to short circuiting arc welding at the welding wire short-circuit detecting circuit 15 of Fig. 1.

Embodiment by the invention described above, welding wire in the time of just making the operator can not feel the starting the arc collides sense, and can not take place to obtain reliable, uniform arc starting performance simultaneously owing to the buckle accident etc. of the molten weldbonding mouth of accident and welding wire of welding wire has caused arc failure.

Claims (1)

1. The feature that one electric welding machine is had is: have the welding current testing circuit whether judgement has welding current and output signal, judge that welding wire and soldered thing are contact short circuit or noncontact, and the welding wire short-circuit detecting circuit of output signal, and with each output signal of above-mentioned welding current testing circuit and welding wire short-circuit detecting circuit as input, again to bonding power control element and the output control circuit of carrying welding wire motor output control signal, above-mentioned output control circuit is to when beginning to weld the starting the arc, the output signal of above-mentioned welding current testing circuit transfers the state that welding current is arranged to, and the output signal of above-mentioned welding wire short-circuit detecting circuit be carried out detecting with the non-contacting state both sides of soldered thing after, the control signal of conversion and control wire feeding motor, make the low velocity of wire feed rate when being lower than stable welding, be that so-called welding wire send starting the arc speed to transfer stable speed of welding to slowly, to welding output element changeover control signal, the high power (hot start power) when making bonding power stablize welding from being higher than transfers stable bonding power to simultaneously.

Images