CN2084856U - Energy saver for electric welder - Google Patents

Abstract

The utility model relates to an energy saver for an electric welder, comprising sampling circuits, an isolating circuit, a comparison circuit, a delay circuit, a logic circuit, an amplifying circuit, a control circuit, etc. The utility model is characterized in that the sampling circuit I and II in the energy saver are both connected between one side of the welder and the distribution board of power, and the connecting wires are power wires which the energy saver supplies for the welder. When the welder starts to work, the sampling circuit I obtains high-level signals which pass through the isolating, comparison, and delay circuits, and then arrive in the logic circuit; the high-level signals are enlarged to trigger a relay to operate, which enables the welder to switch on the power of the normal pressure of 380V, switches off the low-voltage power of 50V, and starts to normally operate.

Description

Energy saver for electric welder

The utility model belongs to the control device that a kind of electric welding machine is used.

During electric welding machine work, under most of occasions, all be in the discontinuous operation state, between its time out, still add rated voltage on the electric welding machine, this will cause bigger open circuit loss, and this moment, the power factor of electric welding machine was also very low, was very disadvantageous for power supply grid.In order to eliminate above-mentioned unfavorable factor, can when electric welding machine is not worked, it be disconnected from electrical network, or reduction applies the voltage on it, but therefore this hell to pay, must realize control automatically, realize automatic control, at first to obtain the work state information of electric welding machine, when electric welding machine is not worked, it be excised from electrical network, work at the beginning, can drop into electrical network rapidly again.

Obtain the approach of electric welding machine work state information, mainly obtain at present from the secondary of electric welding machine.Because when electric welding machine is worked, secondary current is big to hundreds of amperes, and when not working, electric current is zero, can differentiate its duty in view of the above.Also useful high frequency electric source (50KC) is added to that electric welding machine is secondary differentiates its duty, saw the electric world for details 89 years the 7th, 9 phases, when electric welding machine is not worked, the impedance concerning high frequency electric source of its secondary coil is very big, when welding gun is run into workpiece, be equivalent to the high frequency electric source short circuit, differentiate its duty with this, all there is a shortcoming in these methods, the lead-in wire that is energy-saving appliance will be related with the secondary of electric welding machine, and this brings certain trouble to the user, if energy-saving appliance is contained on the electric welding machine, the very poor electric welding machine of condition of work then can have a strong impact on the result of use and the life-span of energy-saving appliance.If draw two lines to energy-saving appliance,, feel inconvenient especially then for often moving the occasion of using from the electric welding machine secondary side.

The purpose of this utility model provides a kind of good energy-conserving effect, electric welding machine energy-saving appliance easy to use.

Its major programme is: obtain the start working sample circuit I of status information and the sample circuit II of electric welding machine welding job status information of electric welding machine in the energy-saving appliance and all be connected between the primary side and power supply switchboard of electric welding machine, and its tie is the power line of supplying with electric welding machine.The sample circuit I is when electric welding machine is started working, the high level signal that obtains is passed through to isolate I, relatively arrive logic circuit after I and the delay circuit I, trigger relay J action after amplifying again, low-tension supply and electric welding machine are disconnected, 380V normal pressure power supply and electric welding machine are connected, then the sample circuit II with the information that obtains by isolating the duty of keeping control circuit after II, comparison II and the delay circuit II, electric welding machine operate as normal.

The utility model has the advantages that energy-saving appliance needn't can directly be loaded on the switchboard from the electric welding machine secondary lead, power supply arrives electric welding machine again through energy-saving appliance, for the user, just the same when not having energy-saving appliance, only draw two power lines and get final product to electric welding machine from switchboard, use more convenient.

Fig. 1 is a block diagram of the present utility model.

Fig. 2 is a schematic circuit of the present utility model.

As shown in Figure 1:

After connecting power supply; suppose that this moment, electric welding machine was not started working as yet, No. 1 junction closure, No. 2 contact disconnects; what add on electric welding machine is elementary is the 50V low-voltage alternating current power supply; be in power save mode, the information that the sample circuit I obtains is by the isolation I in 1# loop---comparing I---, and the delay circuit I arrives logic circuit, owing to be off working state at this moment; therefore; the amplifying circuit no-output, control circuit is not carried out, and maintains the original state with No. 2 contacts for No. 1.When electric welding machine is started working, when welding gun is run into workpiece, the secondary short-circuit condition that is in of electric welding machine; being reflected to the electric welding machine primary side is that impedance reduces; electric current increases, and after the sample circuit I obtained this information, by 1# loop arrival logic circuit was high level signal; through amplifying; make the control circuit action, No. 1 contact is disconnected, No. 2 contact closes; the elementary normal pressure power supply that adds 380V of electric welding machine enters duty.Because No. 1 contact disconnects; 1# does not have information in the loop; the duty high level signal of electric welding machine welding is obtained in the 2# loop by the sample circuit II; the delay circuit II arrives logic circuit---to compare II---through isolating II equally; this high level is after amplifying; make control circuit keep duty, promptly No. 1 disconnected, close for No. 2.In order to guarantee that two loops connect reliably; in the 1# loop, insert the delay circuit I; its effect is when the 1# contact disconnects no information; the time of one section high level is still kept in the output of delay circuit; so that before the high level in 2# loop arrives, do not disappear; thereby guarantee that control assembly keeps duty; consider in addition in real work; might the welding gun short time leave workpiece; do not wish that welding machine enters power save mode at once this moment; because welding job is about to begin at once, thus a delay circuit II in the 2# loop, inserted, in welding gun leaves the workpiece certain hour; electric welding machine is in running order always; when welding machine exceeds the above-mentioned time down time, the effect of delay circuit II disappears, the control circuit action; No. 2 contacts are disconnected; No. 1 junction closure makes welding machine enter power save mode, can avoid the control assembly frequent movement like this.

As shown in Figure 2, low-tension supply is by transformer T, voltage-stabilized power supply DW constitutes, twice side at T behind the connection 380V power supply produces 50V and two groups of voltages of 17V, 17V voltage is through the DW rectification, generation+15V DC voltage after the voltage stabilizing, and the sub-circuit of powering is used, R1 and the KC normally closed contact of 50V alternating voltage in the sample circuit I, current transformer LT is to electric welding machine DH.

The sample circuit I is made of R1, R2, W1, D1, and sample resistance R1 is serially connected on the loop between 50V LVPS and the electric welding machine.After connecting power supply, when electric welding machine DH did not start working as yet, the elementary winding impedance of welding machine was very big, and therefore power supply is very little in the loop, and pressure drop is also very little on R1.W1 is used to regulate sensitivity.

The buffer circuit I is made of every elements T P light, and very little voltage is when loop that R2, W1 and TP form on the R1, and the output triode of TP is obstructed substantially.

The comparison circuit I is made up of R3, R5, R4, C1, IC1, TP no current output, and also no current almost on R4, "+" terminal voltage of comparator IC1 is less than "-" terminal voltage that is produced by R3, R5 dividing potential drop, and therefore, IC1 is output as low level.C1 is an anti-interference capacitor.

The delay circuit I is by R6, C2, D3, R7, R8, D2, IC2, C5 constitutes, IC1 is output as low level, "+" end of IC2 is a low level also just, its "-" end produces a fixing 0.7V voltage by R8-D2, "-" end level is higher than "+" end, so IC2 output is low level also, by D4, in the logic circuit that D8 forms, not conducting of D4, at R15, R14, BG, in the amplifying circuit that D9 forms, BG does not have base current, and also not conducting makes the coil no current of control circuit repeat circuit J and is failure to actuate, its contact J-1 does not conform to, the KC contactor coil does not have electricity, and the KC contact is remained stationary, and electric welding machine is in the low-pressure energy-saving state.

When welding gun is run into workpiece, when electric welding machine is started working, the welding machine secondary loop is in short-circuit condition, be reflected to the elementary impedance decline that is, the primary return electric current increases, therefore pressure drop also increases on sample resistance R1, the led current of TP increases, thereby its triode begins conducting, making R4 go up pressure drop increases, make IC1 "+" end level be higher than "-" end level, the IC1 upset, the output high level produces a direct impulse by capacitor C 2, act on "+" end of IC2, impel it also to overturn, wherein D3, R6 provides discharge loop for C2, after the IC2 upset, capacitor C 5, the R7 charging, make "+" end level keep the high level of a period of time, this high level passes through D4, R15 affacts the BG transistor base, makes the base stage of BG---the emitter stage conducting, the J-1 of relay J, the J-2 closure, J-3 disconnects, and makes the normally opened contact KC-2 closure of KC, and KC-1 disconnects, electric welding machine DH changes the 380V power supply into by the 50V power supply, the work of beginning full voltage goes out indicator lamp BD2 after J-3 disconnection and the J-2 closure, BD1 is bright, shows, electric welding machine has begun operate as normal, and wherein R14 is IC4, the load resistance of IC2.

When electric welding machine enters the full voltage welding; its primary return electric current heightens, and the current transformer LT in the sample circuit II has signal output, and the 2# loop begins action; in the buffer circuit II of forming by DZ, R17, C3; this signal after the C3 filtering (R17 is the load resistance of LT), triggers the comparison circuit of being made up of WG, R9, IC3 through the DZ rectification; affact "+" end of IC3 earlier; this level is higher than "-" end by the fixed voltage that R9 and voltage-stablizer WG produce, and makes the IC3 upset, the output high level.The delay circuit II that triggering is made up of R10, D6, R11, C4, IC4, R13, W2, R12, D10, affact IC4 "+" end by R10, R6, force the IC4 upset, the output high level makes BG keep conducting state by D8, R15 again, be that the KC contact keeps duty, make electric welding machine keep the full voltage duty, as long as electric welding machine is being worked always, LT has signal output always, by the effect of IC3, IC4, BG is conducting always.In case electric welding machine quits work, the LT no-output, at this moment, IC3 "-" end level is higher than "+" end, and IC3 translates into low level, because far away hour R11 of R10, C4 fills high level already with, and under the stopping of D6, C4 can only discharge by R11, because the R11 resistance is big, the velocity of discharge is slow, after after a while, "+" end level of IC4 is lower than its negative terminal level, and IC4 translates into low level, and BG does not have base current, J discharges, and KC also discharges, and electric welding machine is got back to power save mode again, regulate "-" end level that W2 can change IC4, it is worth high, and delay time is short, and its value is low, delay time is long, R13 is an isolation resistance, and R12 is a upper limit resistance, makes its maximum adjusted value can not reach the output high level of IC3, in order to avoid IC4 can not translate into high level, D10 makes lower level be not less than 0.7V, and prevents from can not translate into low level situation because of IC4 lacks of proper care when excessive.

IC1 in the foregoing circuit, IC2, IC3, IC4 are 4 operational amplifiers that a LM324 integrated circuit constitutes, and must note its "+", "-" utmost point during connection, and also available 4 independent operational amplifiers connect.

The utility model can be contained in 1 housing, and then is installed on the switchboard.

Claims (1)

1, a kind of electric welding machine energy-saving appliance, by sample circuit, buffer circuit, comparison circuit, delay circuit, logic circuit, amplifying circuit, control circuit constitutes, when welding machine DH starts working, sample circuit passes through the high level signal that obtains to isolate, arrive logic circuit after relatively reaching delay circuit, trigger relay J action after amplifying again, it is characterized in that obtaining the start working sample circuit I of status information and the sample circuit II that obtains electric welding machine welding job status information of electric welding machine all is connected between the primary side and power supply switchboard of electric welding machine, and its tie is the power line that energy-saving appliance is supplied with electric welding machine.

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