RU2077415C1 - Apparatus for controlling process of gas-shield arc welding by non-consumable electrode - Google Patents

Abstract

FIELD: welding equipment, namely automatic control of electric current mode at gas shield electric arc welding in modes of pulsating arc current. SUBSTANCE: power inputs of source for heating up addition wire are connected with supply industrial mains. First power output terminal is connected with article, second - trough shunt with current collector of welding apparatus. measuring output of shunt is connected with input of matching converter of current signal. Output of said converter is connected with input of unit for switching analog signals. Outputs of unit of digital-to-analog converter are connected with input of electric drive for feeding addition wire and with control input of heating up source. inputs of matching converter of voltage signal are connected with article and current collector; its output is connected with input of said unit for switching analog signals. EFFECT: improved design, enhanced accuracy of controlling process. 1 tbl, 9 dwg

Description

 The invention relates to the field of fusion arc welding, namely, to automatically control and control the electric mode of the non-consumable electrode electric arc welding process in a shielding gas environment, mainly in direct current with the filler wire heated by electric current in the welding process, and can be used in mechanical engineering, shipbuilding, aircraft manufacturing and other industries.

 A device for controlling the process of arc welding with a non-consumable electrode in a shielding gas medium according to copyright certificate No. 1683244, comprising a welding machine controlling a microcomputer, a synchronization unit with a network, a unit for generating tasks and coefficients and an interface unit made in the form of a galvanic separation unit, a controller unit, timer block, block of distribution and amplification of unlocking pulses, block of input of discrete signals, block of digital-to-analog conversion, block of switching of analog signals and unit of the analog-to-digital converter, interconnected by information buses for input and output of discrete information, bus lines of pulse control signals "input" and "output", in which the switching unit of the analog signals by the first and second inputs is connected to the outputs of the matching converters of the current signal and the arc voltage signal non-consumable electrode, the output of the digital-to-analog conversion unit is connected to the input of the electric drive for moving the torch of the welding installation, the information output of the distribution and amplification unit is Piran pulses connected to the power source non-consumable electrode arc.

 The disadvantages of this device are the narrow technological and functional capabilities, since it does not allow welding with a heated filler wire, due to the lack of a feed mechanism and a source of heating of the filler wire, and control the welding machine, which may include these elements.

 The aim of the invention is to expand the technological and functional capabilities of the device due to the ability to control the feed speeds and heating temperature of the filler wire and control the input electric power.

 This goal is achieved by the fact that the device for controlling the process of arc welding with a non-consumable electrode in a protective gas environment contains a welding installation that controls the microcomputer, including a microprocessor, a memory unit, a control unit for input-output devices and a parallel interface, a block synchronization with the network, a unit for generating tasks and coefficients and a pairing unit made in the form of a galvanic separation unit, a controller unit, a timer unit, a distribution and amplification unit of unlocking pulses, and the input of discrete signals, an analog signal switching unit, an analog-to-digital conversion unit and a digital-to-analog conversion unit, interconnected by information lines of input and output of discrete information, pulse bus signals of input and output, in which the first and second information outputs, the first and second control pulse outputs and the first information input of the control microcomputer are connected respectively to the first and second information inputs, with the first and second control inputs and the first information output of the interface unit, the first and second pulse outputs of the interface unit are connected respectively to the first and second interrupt inputs of the control microcomputer, the first and second information, first and second control inputs of the interface unit are connected through the galvanic isolation unit to the inputs of junior and inputs, respectively senior bits, with the first and second control inputs of the controller unit, the first information output of which is connected through the galvanic separation unit to the first the information output of the interface unit, the second information output, the first and second pulse control outputs of the controller unit are connected respectively to the information inputs, the first and second control inputs of the timer unit, the input unit of the discrete signals, the distribution and amplification blocking block pulses, the digital-to-analog conversion unit, the analogue unit -digital conversion and switch block analog signals, two pulse and analog outputs of which are connected respectively to the first and second pulse and analog inputs of the analog-to-digital conversion unit, the information and pulse outputs of which are connected respectively to the 16-bit information and third pulse inputs of the controller unit, the third and fourth pulse outputs of which are connected respectively to the second and additional third pulse outputs of the interface unit, the fifth pulse output the controller unit is connected to the third control input of the analog signal switching unit and the third control input of the analog-qi unit rovogo conversion. In this case, the synchronization unit with the network is connected by a pulse output to the first pulse input of the controller unit, an information output and a control input with the corresponding information input and pulse output of a discrete signal input unit, the task and coefficient generating unit is connected by its information outputs and corresponding pulse inputs to a discrete input block signals, the switching unit of analog signals by the first and second inputs is connected to the outputs of the matching converters of the current signal and the signal la arc voltage, the output of the digital-to-analog conversion unit is connected to the control input of the electric drive for moving the welding torch, the information output of the distribution and amplification blocking pulses is connected to the power source of the arc of the welding unit.

 The proposed device is characterized in that the welding installation is equipped with a mechanism and an electric drive for supplying filler wire with a control input, a heating source for filler wire with a control input, power inputs and two power output terminals, a second shunt and a second matching current signal converter, a second matching voltage signal converter, the analog signal switching unit is additionally equipped with third and fourth analog inputs, and the digital-to-analog conversion unit second and third analog outputs, with the power inputs of the heating source connected to the industrial supply network, the first power output terminal connected to the product, and the second through the second shunt to the current collector of the welding unit, the measuring output of the second shunt is connected to the input of the second matching current signal converter, output which is connected to the third input of the analog signal switching unit, the second output of the digital-to-analog conversion unit is connected to the input of the frequency filler wire feed drive, the third output of the digital-to-analog conversion unit is connected to the control input of the filler wire heating source, the inputs of the second matching voltage signal converter are connected to the product and the current collector, and the output is to the fourth input of the analog signal switching unit.

 As a result of the patent research, no significant features similar to the distinctive features of the claimed device were found to be used in the proposed manner, and therefore, the proposed technical solution meets the criterion of "significant differences".

 The essence of the proposed technical solution is illustrated by drawings, where in FIG. 1 shows a functional diagram of a welding installation with an automatic control device based on a control microcomputer; in FIG. 2 is a functional diagram of the interface unit of the control microcomputer with the blocks of the welding installation; in FIG. 3 diagram of the arc welding process on the interval of the arc current pulse; in FIG. 4 diagram of the arc welding process in the interval of the pause of the arc current; in FIG. 5 graphs of the current-voltage characteristics of the arc of a non-consumable electrode for various values of the arc gap; in FIG. 6 time diagrams of cycles of current change of non-consumable electrode and control signals of electric drive and current of filler wire; in FIG. 7 is a structural diagram of a source for heating filler wire; in FIG. 8 functional block diagram of digital-to-analog conversion; in FIG. 9 is a block diagram of the algorithms of the main part of the microcomputer control program and interrupt service routines.

The following symbols are used in the figures: 1 welding unit; 2 - control microcomputer; 3 microprocessor; 4 memory block (RAM and ROM); 5 - control unit input / output devices; 6 parallel interface; 7 - block synchronization with the network; 8 block forming tasks and coefficients; 9 - block interface control microcomputer with a welding installation; 10 galvanic separation unit; 11 controller block; 12 block of timers; 13 - block distribution and amplification of the unlocking pulses; 14 block input discrete signals; 15 block digital-to-analog conversion; 16 block switching analog signals; 17 block analog-to-digital conversion; 18 mechanism for moving the head with the electrode; 19 electric motor; 20 power amplifier; 21 products from welded parts; 22 source of welding current; 23 shunt current sensor non-consumable electrode; 24, 25 matching converters of analog current signal and arc voltage; 26 - positional electric drive moving the welding head; 27 microcomputer interrupt input by timer signals; 28 pulse output of the timer block; 29 16-bit information input of the parallel interface; 30 first 8-bit information output of the parallel interface; 31 second 8-bit information output of the parallel interface; 32 control output pulse signal "data input" parallel interface; 33 - control output pulse signal "data output" parallel interface; 34 input signal "requirement A" of the upper level (TPA) parallel interface; 35 - input signal "requirement B" of the upper level (TRB) parallel interface; 36 first information output of the interface unit; 37 first information input of the interface unit (input of the least significant bits VD00.VD07); 38 second information input of the interface unit (input of the upper digits VDOV.VD15); 39 - control input pulse signal "DATA ENTRANCE" interface unit; 40 - control input pulse signal "data output" of the interface unit; 41 - pulse output of the signal "requirement A" of the upper level (TPA B) of the interface unit; 42 pulse output of the signal "requirement B" of the upper level (TRB C) of the interface unit; 43.45 network inputs of block 7 synchronization with the network; 46 input control unit 7; 47 multi-bit information output of block 7; 48 - pulse output of block 7; 49, 50 multi-bit information outputs of block 8 of the formation of tasks and coefficients; 51, 52 single-wire control inputs of block 8; 53 trigger register block 11 of the controller; 54 input synchronization trigger register 53; 55 inverter-amplifier register; 56.58 - shaper amplifiers; 59 16-bit information input of block 11; 60 - 16-bit information output of block 11; 61 pulse output signal "input" (BB) and block 11; 62 pulse output signal "output" (VD) and block 11; 63 - pulse input signal TPA block 11; 64 pulse input signal TRB In block 11; 65 pulse output signal TRBMV block 11; 66 pulse output of a block of 12 timers; 67 information input block 12 timers; 68, 69 control inputs of the block 12 timers; 70 multi-bit information input unit 13 distribution and amplification of the unlocking pulses; 71 code output of block 13; 72, 73 control inputs of the discrete signal input unit 14; 74 16-bit information output of block 14; 75 main 16-bit information input of block 14; 76.78 signal information inputs of block 14; 79.81 single-wire control outputs of block 14; 82 multi-bit information input block 15 digital-to-analog conversion; 83 control input of block 15; 84 analog output of block 15; 85 multi-bit information input of the switching unit 16 analog signals; 86.88 control inputs of block 16; 89, 90 pulse outputs of block 16; 91, 92 analog inputs of block 16; 93 - analog output of block 16; 94 multi-bit information output unit 17 analog-to-digital conversion; 95 pulse output of block 17; 96.98 - control inputs of block 17; 99 analog input of block 17; 100 welding head; 101 non-consumable electrode; 102 filler wire; 103 - feed rollers; 104 filler wire feeder; 105 spool of filler wire; 106, 107 power terminals of the welding source 22; 108 electrode holder; 109 current collector; 110 insulating tube; 111 - nozzle; 112 main arc; 113 weld pool; 114 active spot of the arc; 115 electric motor; 116 power amplifier; 117 electric filler wire feed; 118 source of filler wire heating; 119, 120 power terminals of the heating source 118; 121, 122 second and third outputs of the DAC block 15; 123 shunt for measuring current of filler wire; 124 matching filler wire current transducer; 125 - matching voltage signal converter; 126, 127 the third and fourth inputs of block 16; 128, 129 current sensors non-consumable electrode and filler wire, respectively; 130 source comparing element 118; 131 - dynamic source control 118; 132 controlled semiconductor rectifier source 118; 133 current sensor source 118; 134 source shunt 118; 135 matching Converter current signal source 118; 136.138 trigger registers of block 15; 139 141 trigger synchronization inputs. 142, 144 digital-to-analog converters; 145 address decoder; 146.149 operational amplifiers; 150.154 resistors;
In FIG. 3 6 are indicated: i _ne , U _ne current and arc voltage of the non-consumable electrode, respectively; i _p , U _p current and voltage of the filler wire heating, respectively; l _{day the} length of the arc gap non-consumable electrode; l _AB section of the heated wire, in a solid state; l _BC section of a heated wire in a liquid state; l _CD section of a heated wire in a plasma state; U _c pulses of the synchronization voltage at the pulse output 48 of block 7; i _ne graph of the change in the current of the non-consumable electrode in a pulsating mode; x _ne - graph of changes in the control action of the electric drive moving the head; x _n schedule changes in the control action of the source of heating of the filler wire; k control cycle number; j control cycle number; T _f , T _c , T _c , T _p , T _c time intervals of the front, top, fall, pause, and pulse cycle of the arc current of the non-consumable electrode, respectively.

 The microcomputer device for controlling the process of non-consumable electrode arc welding in a shielding gas environment includes a welding unit 1 that controls the microcomputer 2 (microcomputer), including a microprocessor 3, a memory unit 4, a control unit 5 for input and output information devices and a parallel interface 6, a synchronization unit 7 with a network, a unit 8 for generating tasks and coefficients, and a unit 9 for interfacing the microcomputer 2 with the control object. The interface unit 9 comprises a galvanic separation unit 10, a controller unit 11, a timer unit 12, a digital output unit 13, a digital input unit 14, a digital-to-analog conversion unit 15, an analog signal switching unit 16 and an analog-to-digital conversion unit 17.

 The welding unit 1, which is the control object for the microcomputer, contains a mechanism 18 for moving the welding head with a non-consumable electrode, an electric motor 19, a power amplifier 20, parts of the welded article 21, a source of current 22 of the non-consumable electrode, shunt 23, matching converter 24 of the current signal and matching converter 25 of the arc voltage signal. The combination of the movement mechanism 18, the electric motor 19 and the power amplifier 20 is a positional electric drive 26 for moving the welding torch. This drive has an analog input for setting the amount of displacement, which is the input of a power amplifier 20, through which an analog voltage control signal is supplied to the drive.

 The interface unit 9 (Fig. 2) is connected with its first pulse output 28, which is the output of the timer unit 12, to the first interrupt input 27 of the control microcomputer 2, which is the timer interrupt input of the microprocessor 3.

 Microcomputer 2 (control microcomputer) has a 16-bit information input 29 that matches the information input of the parallel interface 6, the first 8-bit information output 30 and the second 8-bit information output 31, matching the corresponding outputs of the parallel interface 6, control outputs 32 and 33 pulse signals respectively "data input" and "data output", which are respectively the first and second pulse outputs of the parallel interface, pulse inputs 34 and 35 signals, respectively, "requirements A" top level (TPA B) and the requirement B "upper level (TRB C), which are simultaneously the same functional inputs of the parallel interface. Inputs 34 and 35 are respectively the second and third pulse interrupt inputs of the control microcomputer.

 Block 9 interfacing with its second pulse output 41, connected with the pulse output 48 of block 7 of synchronization with the industrial network 380/220 B, is connected to the pulse input 34 "requirement A" of the parallel interface 6, which is the second input 34 of the interruption of the control microcomputer 2, connected by its first and second information outputs 30 and 31, first and second control pulse outputs 32 and 33, and first information input 29 with first and second information inputs 37 and 38, first and second control pulse inputs 39, 40 and first information yield 36 nnym unit 9 conjugation.

 The third pulse input 63, the third information input 76 and the third pulse output 79 of the interface unit 9 are connected respectively to the pulse output 48, the information output 47 and the control input 46 of the unit 7 for synchronizing the device with the industrial network. The fourth and fifth information inputs 77 and 78, the fourth and fifth pulse outputs 80, 81 of the coupler 9 are connected respectively to the first and second information outputs 49, 50, the first and second pulse inputs 51 and 52 of the unit 8 for generating tasks and coefficients.

 Block 13 distribution and amplification of the unlocking pulses has one information input 70 and one information output 71.

 Block 15 digital-to-analog conversion has one multi-bit information input 82, one pulse control input 83 and three analog outputs 84, 121, 122.

 Block 16 switching analog signals has four analog inputs 91, 92, 126, 127, three control inputs of the signals "Input" 88, "Output" 87 and TRBMV 86, one multi-bit information input 85, two pulse outputs SBR 89 and on-load tap-changer 90 and one analog output 93.

 Block 17 analog-to-digital conversion has one analog input 99, three pulse control inputs for signals RRF 97, RPN 98 and TRBMV 96, one pulse output signal TRB V 95 and one multi-bit information output 94.

 The block 19 of the interface of the control microcomputer 2 with the welding installation has a sixth pulse output 42, which is connected to the input 35 "requirement B" of the parallel interface 6.

 The output of the current signal converters 24 and the arc voltage signal 25 are connected respectively to the first and second analog inputs 91 and 92 of the analog switch 16, which are the first and second analog inputs of the interface unit 9, respectively. The analog output 84 of the interface unit 9, connected to the analog output 84 of the digital-to-analog conversion unit 15, is connected to the analog input of the power amplifier 20 of the electric drive 26 to move the welding head 100. The second information code output 71 of the interface unit 9, which is the code output 71 of the distribution unit 13 and gain unlocking pulses, connected to the control inputs of the unlocking of semiconductor valves (thyristors) of the power source 22.

 The controller unit 11 comprises a trigger register 53 with a synchronization input 54 for storing the system address of that block from the interface unit 9 to which the microcomputer processor 2 is accessing, inverter-amplifier register 55 for improving edges when transmitting an information word output from the microcomputer, amplifiers-shapers 56, 57 and 58 of the signals "input", "output" and TRBMV, respectively. Bus 36 of information input into the microcomputer is connected through the galvanic separation unit 10 and the controller unit 11 directly to the data input bus 59 of the interface unit 9. The output information buses 31 of the parallel interface, containing the highest 8 bits, are connected through the input 38 of the interface unit through the galvanic isolation unit 10 to the information input of the 8-bit trigger register 53, the synchronization input 54 (input “record”) of which is connected to the output of the amplifier-driver 56 The 8-bit output of the trigger register 53 and the output bus 30 of the lower eight eight bits of information output via the parallel interface 6, through the galvanic isolation unit 10, are connected through a 16-bit inverter-amplifier register 5 5 to the data output trunk buses 60. The input confirmation bus 32 and the output confirmation bus 33 are connected through the galvanic separation unit 10 and the driver amplifiers 56 and 57 to the input "main" 61 and "output" 62 main control buses, respectively.

 The controller unit 11 is equipped with a TRBMV pulse signal generator 58, a pulse input 64 and two pulse outputs 42 and 65. In this case, the first 37 and second 38 information, the first 39 and second 40 control inputs of the interface unit 9 are connected through the galvanic isolation unit 10, respectively, to the register inputs 55 low order bits and 53 high order register inputs, with the first and second control inputs of the shapers 56, 57 of the controller unit 11. The first information output of the controller unit 11 is connected through the galvanic separation unit 10 to the first information output 36 of the interface unit 9, the second information output 60, the first and second pulse control outputs 61, 62 of the controller unit 11 are connected respectively to the information inputs, the first and second control inputs of the unit 12 timers 67, 68, 69, block 14 input of discrete signals 75, 72, 73, block 13 distribution and amplification of unlocking pulses 70, block 15 digital-to-analog conversion 82, 83, and switch 16 analog s signals 85, 87, 88. The pulse outputs of the signals of the RBU 89, on-load tap-changer 90 of the analogue switching unit 16 and the analog output 93 of the latter are connected respectively to the first and second pulse inputs of the RBU 97 and on-load tap-changer 98 and the analogue input 99 of the analog-to-digital conversion unit 17. Information and pulse outputs 94 and 95 of the block 17 analog-to-digital conversion are connected respectively to the second information 59 and second pulse 64 inputs of the block 11 of the controller. The pulse output of the controller unit 11, connected to the additional input 64, is connected through the galvanic separation unit 10 to the second additional output 42 of the interface unit. The input 64 through the shaper 58 is connected to the output 65 of the signal TRBMV, which is connected to the third input 86 of the control unit 16 of the switch analog signals and the third control input 96 of the block 17 of the analog-to-digital conversion.

 Block 14 input discrete passive signals is used to enter into the microprocessor computing unit 2 discrete information in parallel binary code from various discrete devices and generally has several input channels specified by their addresses.

 The welding unit 1 also includes a welding head 100, moving relative to the welded product 21, on which a non-consumable electrode 101 is mounted, parallel to which the filler wire 102 moves. The filler wire 102 is wound using feed rollers 103 of the filler wire supply mechanism 104 from the coil 105. The input power terminals of the welding source 22 are connected to the workshop three-phase supply network (Fig. 1). The first output terminal 107 of the power supply source 22 of the main arc 112 is connected through a shunt 20 to the welded product 18, the second output terminal 106 is connected to a non-consumable electrode 101. An electrode holder 108, a current collector 109, an insulating tube 110, a nozzle 111 are mounted on the welding head 100 the inert gas is supplied to the welding zone. During welding, between the non-consumable electrode 101 and the article to be welded 22, the main arc 112 continuously burns, under the influence of which a welding bath 113 is formed on the product. The current of the non-consumable electrode 101 is closed to the article to be welded 22 through the arc column 112 and the active arc spot 114 located on the welding bath 113.

 The combination of filler wire supply mechanism 104 with feed rollers 103, electric motor 115 and power amplifier 116 is a speed-adjustable electric filler wire supply 117, which controls the speed of its filing in the weld pool 113 according to a certain law. This electric drive has an analog input for setting the speed of the electric motor and filler wire supply, which is the analog input of the power amplifier 116, through which a voltage control signal is supplied to the latter. The second output 121 of the block 15 digital-to-analog conversion is connected to the analog input of the speed reference of the drive 117.

 The filler wire heater 118 may have various structures and characteristics. In this device, as an example, a dc or ripple current stabilizer controlled by an input analog signal is selected (Fig. 7). The power inputs of source 118 are connected to the workshop three-phase power supply network, the output power terminal 120 is connected to the product 21, the output power terminal 119 is connected through the power terminals of the shunt 123 to the current collector 109, the measuring terminals of the shunt 123 are connected to the inputs of the matching converter 124 of the current signal, the output of which is connected to the third input 126 of the block 16 switching analog signals. The third output 122 of the digital-to-analog conversion unit 15 is connected to the analog input for setting the value of the heating current of the filler wire of the source 118. The inputs of the second matching voltage signal converter 125 are connected to the product 21 and the current collector 109, and the output to the fourth input 127 of the analog signal switching unit 16. The shunt 123 and the matching converter 124 of the current signal form a sensor 129 current filler wire.

 Source 118, which is a direct current stabilizer controlled by an analog signal with a steeply falling (bayonet) external characteristic, contains the following main elements (Fig. 7): comparison element 130, the first input of which is connected to the analog input of source 118 and is a control input setting the magnitude of the output current of the latter, a dynamic controller 131, a controlled rectifier 132, made, for example, in the form of a three-phase Larionov bridge, with a controlled thyristor valve in each of the six arms and a current sensor 133 of the source 118, containing, for example, a series-connected shunt 134 of the source 118 and a matching converter 135 of the current signal of the source 118. The output of the comparison element 130 through the dynamic controller 131 is connected to the input of the controlled rectifier 132. It is connected to the output power terminal 120 by its power terminals a shunt 134 of the sensor 133 of the output current of the source 118. Two measuring terminals of the shunt 134 are connected to two inputs of the matching Converter 135, the output of which is connected to the second input of the comparison element 130, forming Cored oil negative feedback circuit output current source 118. An instance of the source can be controlled rectifier welding type VSVU-400, commercially available from RPO "Electromechanics" in Rjeff.

 Matching converters 24, 25, 125, 124, 135, perform the functions of galvanic separation, amplification and normalization of the measured current signals and voltage signals.

 Block 15 digital-to-analog conversion (Fig. 8) is multi-channel and contains trigger registers 136.138 with inputs 139.141 synchronization, digital-to-analog converters (DAC) 142.144, address decoder 145, operational amplifiers 146-149 resistors 150.154.

 Each of the trigger registers 136.138, for example 136, contains a certain number (for example, 10) of edge-triggered DS triggers, each of which has information and synchronization inputs. The clock inputs of all triggers of any register are combined, form its common clock input 139 and are controlled from a single signal. Information inputs from the first to the ninth triggers of the register 136 are connected to the corresponding from the first to the ninth main data output buses VD00-VD08 of the pairing unit 9. The tenth main data output bus VDO9 through the inverter, which is part of the register 136, is connected to the information input of the tenth, sign, trigger of the register. As a result of this inclusion, the information signal supplied to the tenth trigger is inverted, which is necessary to obtain a bipolar signal at the output of the DAC.

 The address decoder 145 has a multi-bit information input 82 and a control input 83, is based on a 16-directional decoder chip K155IDZ type and contains an address setting unit, a two-input match logic element, logical inverters (not shown in Fig. 8 for simplicity). The information, for example, 6-bit, input of the address decoder 145 is connected to the corresponding data output lines VD10.VD15 from the eleventh to sixteenth. The control input 83 of the decoder 145 is connected to the “output” control bus. The outputs of the decoder 145 are connected to the corresponding inputs 139. 141 synchronization trigger registers 136.138. By rearranging the jumper wires in the decoder address setting node, it is possible to reserve for block 15 a certain set of 6-bit binary addresses according to the number of channels in the upper part of the 16-bit data word output from the computer processor via buses 60-82. The format of the output word for block 15 digital-to-analog conversion is shown in the table.

 The outputs of the trigger registers 136, 137, 138 are connected to the information inputs of the corresponding digital-to-analog converters 142, 143, 144. The latter are used to convert a 10-bit digital binary positional code with a sign into analog voltage signals and are based on K572PA1 microcircuits. Signed is the most significant bit of the data code. The analog outputs of the digital-to-analog converters 142, 143, 144 are connected to the inverting inputs of the output operational amplifiers 146, 147, 148, respectively, the outputs of which are connected to the outputs of the feedback resistors of the corresponding DAC circuits 142, 143, 144.

 The device operates as follows.

The welding mode is usually set by the cyclogram. The number of programmable sections of the sequence diagram depends on the number of controlled parameters of the mode and is determined mainly by the volume of the memory (RAM) of the control microcomputer 2. The program of dialogue with the operator-welder and control of the welding process is stored in a permanent memory (ROM) of the memory unit 4. After turning on the power, the microprocessor 3 of the control computer 2 issues commands through the parallel interface 6 and the interface unit 9 to switch the corresponding control circuits of the welding unit 1 (not shown for simplicity), setting the values of the welding voltage and current, voltage and current of the filler wire heating source to zero , welding speeds, filler wire feed speeds and the movement of the welding torch along its axes of movement (not shown). Then, the microprocessor 3 gives a command to move the welding head 100 vertically to its initial position, the value of which (arc gap l _dne ) can either be selected from the memory unit 4 or set by the switches of the unit 8 for generating tasks and coefficients. This command through blocks 6, 10, 11, 15 is fed to the input of the power amplification unit 20 of the positional electric drive 26, voltage is supplied to the electric motor 19, and the latter, driving the mechanism 18, moves the welding torch with non-consumable electrode 101 to a predetermined initial position.

After completion of the session of positioning the welding head by the operator-welder in the dialogue mode with the host computer 2, all the necessary parameters of the sequence diagram of the welding mode are entered. These parameters are entered from the keyboard and displayed on the display through the block 5 control input / output devices. In the welding installation, various other devices for signaling and displaying input and technological information may be provided, which are not considered here to reduce the application volume. In this case, regardless of the number of programmable sections, the first section of the cyclogram defines a certain sequence of supply of protective gas, inclusion of arc currents i _ne (non-consumable electrode) and filler wire i _p . In the case of argon-arc welding under consideration, the main arc in the first section can be excited without an oscillator by feeding the filler wire until it touches the article 21 from the parts to be welded and then withdrawing it to a small distance from the arc using the filler wire drive 117. In the first section, its duration in time, the magnitude of the initial (standby) current of the non-consumable electrode, the initial heating current of the filler wire, and the distance of the electrode 101 from the item being welded (arc gap length l _day ) are set. The parameters of all other sections of the sequence diagram are set similarly: the values of their durations in time, currents of the electrode and filler wire, magnitude of movement of the head, voltages on the electrode and current collector, welding speeds and filler wire feed. In this case, the microprocessor 3 through block 5 reads the entered parameters, enters them into the RAM of the memory block 4 and displays their values on the display or other means of displaying information available in the system.

Recently, when arc welding with a non-consumable electrode in a protective gas environment with direct current, pulsating direct current modes are widely used. When this mode is set during a dialogue with the control computer, the operator-welder enters the selected pulsed constant current mode values for the selected sections of the welding sequence (see Fig. 6): cycle duration T _c , duration of the rise front of the non-consumable electrode T _f , duration of the pulse peak current electrode _T, the duration of decrease T _c, the pause time T _p and the duty value of the electrode current I and _ne1 filler wire current I _n1 pause interval on the electrode current and the magnitude of the electrode current I and _ne2 prisadoch oh I _n2 wire for a current pulse interval of the electrode, and the value of the velocity V _n of the filler wire feeding. These parameters specified for each of the sections of the sequence diagram are also entered by the microprocessor 3 in the RAM unit 4 memory.

 After turning on the power supply and starting the program, the program-setting block 4 of the RAM and ROM of the control microcomputer 2 performs the initial reset and installation of all external devices and blocks, turns on the interrupt system of the microprocessor 3 and generates certain laws for controlling the executive bodies: power sources of the electrode arc and heating of the filler wire, electric drive head movement and filler wire feed. The set values of the operating mode code, the value of the initial arc gap, the current of the non-consumable electrode, the current of the filler wire heating, the wire feed speed and other necessary parameters (system information), for example, are read in the binary code by the microprocessor 3 via the parallel interface 6, block 14 for inputting discrete signals from block 8 of the formation of tasks and coefficients.

Further, during operation, the current values of the parameters l _dne , I _ne , I _p , V _p , are adjusted in accordance with the values of the feedback signals input from the output 94 of the block 17 of the analog-to-digital conversion at the inputs 91, 92, 126, 127 of the switching unit 16 analog signals, in accordance with the developed control laws. Then, the program calculates the necessary sequence of time-varying unlocking angle α of the valves, and the first value of the angle a in binary code is prepared for its output to the information input 67 of the corresponding clock counter of block 12.

 Block 12 counters of clock pulses contains three binary software-controlled counters of clock pulses and a control unit of counters. The counters can be downloaded in binary codes and controlled programmatically through the blocks of the parallel interface 6, galvanic isolation 10, controller 11. Counters are used to "measure" the time intervals corresponding to the specified or calculated values of the opening angle of the valves of the power thyristor source 22, and count the clock pulses from the master high-frequency clock generator. The outputs of the counters are combined by OR and form a pulse output 28 of block 12, which in turn is connected to the interrupt input 27 of the microprocessor 3 to start the interrupt service routine of the control computer 2 from the clock counters (timers).

 Block 13 is used to form, amplify and distribute the unlocking pulses through the valves of the power valve converter of the source 22 of the power supply of the arc of the electrode.

 Detailed descriptions of the specific implementation and operation of the block 12 counters of clock pulses, block 13 gain and distribution of unlocking pulses and block 7 synchronization with the network are given in a.c. USSR N 1146781 and N 1205243.

 In the following presentation, the concept of "network voltage zone" is used for the K-th valve of the bridge, introduced in A.S. N 1146781. Recognition of the current zone number is carried out using zero-organs and a phase polarity recorder of a three-phase power supply unit 7.

 The control microcomputer 2 has been operating for the entire time that this device has been functioning since its power was turned on according to the program stored in the memory unit 4, in accordance with the algorithm shown in FIG. 6 and 9. The program is executed by the microprocessor 3 cyclically, in cycles, the beginning of each cycle corresponds to the leading edge of the synchronization pulse (see Fig. 6a). Each network voltage zone corresponds to one control cycle (synchronization interval), in which the value of the unlocking angle a of the next valve is calculated, the corresponding output code for unlocking the valves is determined and issued. The synchronization pulses coming from the null organs of block 7 interrupt the program six times during the period of the supply network. At the beginning of each Kth step, the microprocessor reads system information, for example, via channels 77-49 and 78-50, and technological information from blocks 7, 16, 17, 24, 25, 124, 125, containing recorders and sensors of controlled quantities and parameters .

 After receiving the interrupt signal in the form of a high-level pulse from the output 48 of the block 7, which is input to the input 63 of the interface unit and then from its output 41 to the input 34 of the parallel interface 6. of the controlling computer, the microprocessor, in accordance with the program, switches to the interrupt service routine from the synchronization pulse, at the beginning of which it resets the corresponding interrupt trigger in block 7. As a result, the output voltage 48 of block 7 again sets a low voltage level, i.e. block 7 is preparing for a new cycle of work. Then, the microprocessor from the output 49 of the unit 8 for forming tasks and coefficients through the input 77 of the unit 14 of the controller unit 11 and the galvanic separation unit 10 reads the code of the operating mode of the device and the welding unit and analyzes it. If the operator sets the automatic operation mode of the device and installation with the issuance of control actions and a command is given to start the welding process, the microprocessor proceeds to the corresponding block of the control program and reads all the parameters of the system and technological information.

System information is information set by the operator of the welding machine in dialogue mode or during operation using the program switches of unit 8 for generating tasks and coefficients, buttons, toggle switches, etc. As mentioned above, such information is: code of the operating mode of the welding machine, settings (reference) values of the initial length of the arc gap _dneo l, l _dnemin its minimum and maximum values of l _dnemax, the cycle time T _c in pulsating current mode, the parameters T _{p, T,} T _c, T _f, current neplavyascheg Xia _NEO I electrode, a filler wire heating current I _on, the wire feed speed V _on, and all other parameters cyclogram welding. The values of the operating mode code, the length of the arc gap, and all other system coefficients and parameters of the sequence diagram, set by the operator in block 8, can be changed by him at any time during the welding process. At the next synchronization pulse, these values are re-read by the microcomputer 2 through the pairing unit 9 and stored in the memory for immediate use by the program.

 Technological information is information reflecting the progress of the welding process: i.e. sensor readings of all measured values and controlled technological parameters. In this case, these are the values of the current and voltage of the non-consumable electrode, introduced from the sensors 128 and 25, the current and voltage of the filler wire, introduced from the sensors 129 and 125 through blocks 16, 17, 11, 10 into the control microcomputer 2.

The power source 22 of the main arc 112 begins to generate a predetermined current value I _ne , which through terminal 107, the shunt 23 enters the welded product 21, then through the active spot 114 of the arc 112 and the non-consumable electrode 101 returns through the terminal 106 to the source 22. Moreover, on the product 21, a weld pool 113 is induced, into which filler wire 102 (FIGS. 1 and 3) then begins to be fed by means of rollers 103 of mechanism 104, driven by a speed-adjustable electric drive 117.

As the weld pool 113 is formed and the process is established, the main arc 112 is moved to move the torch with the electrode 101 along the welded joint, and the distance between the non-consumable electrode 101 and the active spot 114 of the arc 112 on the surface of the weld pool is maintained by the positioning electric drive 26 of moving the welding head 100 113 in accordance with the foregoing method, maintaining constant the average deviation d _{nej of the} real current-voltage characteristic of the main arc from the reference.

The filler wire supplied to the weld pool is heated by the Joule heat generated by the wire current I _p passing through it from the terminal 120 of the filler wire heating source 118 to the welded product 21, then through the weld pool 113, active spot 114 of the arc 112, the melted end wire 102 (departure), current collector 109, shunt 123 and returns through terminal 119 to source 118.

The magnitude of the speed V _p filler wire set programmatically in digital form. The microprocessor 3 reads from the RAM unit 4 the memory from the data array of the parameters of the weld pattern, entered by the operator, the digital speed code V _p for this section of the pattern and issues it through the parallel interface 6 of the control computer 2 to the pair 9, through the block 10 galvanic separation, block 11 controller in block 15 digital-to-analog conversion, in which this code is converted into analog form. The value of the received analog voltage signal U _{Vп back} corresponds to a certain value of the filament wire feed speed V _p specified in the program. From the output 121 of the block 15, the analog signal U _{Vп back} goes to the input of the speed reference of the filler wire 117.

The current value I _{p of} heating the filler wire is also set programmatically in digital form. The microprocessor 3 reads from the RAM of the memory unit 4 from the data array of the parameters of the welding sequence diagram entered by the operator, the digital current code I _{p of the} filler wire heating for the selected section of the sequence diagram and outputs it through the parallel interface 6 of the control computer to the interface unit 9 through the galvanic separation unit 10, unit 11 of the controller to the digital-to-analog conversion unit 15, in which this code is converted to analog form. The magnitude of the received analog voltage signal U _{Ip ass} corresponds to a certain current value I _{p of the} filler wire heating specified in the program. From the output 122 of block 15, the analog voltage signal U _{Ip ass is} supplied to the input of the task of the current value of the source 118 heating. This voltage is supplied to the first (master) input of the comparison element 130 (see Fig. 7), to the second input of which (feedback input) a voltage signal U _Iп oc is _received , taken from the output of the current sensor 133. The comparison element 130 generates a voltage difference signal at its output
_Rin U _n U U _{Ip Ip ass wasps}
corresponding to the set value of the current heating the filler wire. _Rin signal U _n goes to dynamically control input 131, where it is superimposed on a dynamic voltage component, which improves transient current change process, and then outputted from the dynamic controller 131 to the input of the control rectifier 132. Last converts three-phase alternating current commercial power supply into a direct current setpoint I _p . The magnitude of this current is recorded 133 shunt current sensor 134 is amplified and normalized current signal aligner 135, the output of which is produced U _{Ip os} signal proportional to current supplied by the source 118. As the source 118 is a complete serial device, a current sensor 113 is its inherent an internal element, so the signal from the current sensor 113 may not be available for input into the microprocessor control device in question.

The current value I _{p of the} filler wire is simultaneously recorded by the shunt 123 of the current sensor 129, amplified and normalized by a current signal coordinator 124, the output of which is generated by a signal U _Iп proportional to the instantaneous value of the source current 118. This signal is fed to the input 126 of the analog signal switching unit 16. The voltage of the source 118, taken from the current collector 109 and the welded product 21, is fed to two inputs of the matching converter 125 of the voltage signal, in which it is amplified, normalized, and from the output of the converter 125 passes to the input 127 of the switching unit 16. Subsequently, at the command of the microprocessor, these signals are transmitted to block 17, in which they are converted from analog to digital form, and already digitally transmitted through blocks 17, 11, 10, 6 to microprocessor 3 for further processing and use.

 This device described above is designed to implement a new method proposed by the same author in a separate application for the invention of a method for controlling the process of non-consumable electrode arc welding in a shielding gas medium with filler wire feed. The essence of the proposed method is as follows.

 At the beginning of the welding process, a non-consumable electrode is installed at a predetermined distance from the parts to be welded, the main arc is excited between the non-consumable electrode and the parts to be welded at the standby current of the electrode, and then welding is performed at the rated current of the electrode, feeding a filler wire at a constant speed, which is heated, passing through it through an arc the heating current from a separate source of heating the direct current. In the pulsating current mode, specify the reference (Fig. 5) current-voltage characteristic of the main arc from the non-consumable electrode for a given constant value of the filler wire feed speed, while adjusting the welding current of the non-consumable electrode, the real dynamic current-voltage characteristic of the main arc for the specified constant value of the feed speed is taken filler wire, for which the current and voltage of the non-consumable electrode are measured in the interval of increase in current in each cycle, compared with the reference wave t-voltage characteristic, the average deviation value determined actual current-voltage characteristic of the reference for all clocks rise interval formed control action proportional to the mean value of the deviation and compensate this influence average value of the corresponding deflection by changing the distance between the non-consumable electrode and the welded parts.

 In this case, a series of synchronization pulses is generated, each of which is formed at the moment of zero transition of one of the six linear voltages of a three-phase industrial network. With the help of these pulses, the entire process of automatic regulation and control of arc welding is divided into successive Kth cycles, each N of which make up the jth control cycle, and the current and voltage of the non-consumable electrode are measured along the leading edge of each synchronization pulse at the beginning of each control cycle.

On each j-th cycle, a control action X _{Ney is generated} in digital form for the positional electric drive moving the head in deviation in accordance with the ratio
x _nej = k _epg • δ _nej ... (1)
where X _nej control action for the electric drive moving the head with a non-consumable electrode;
K _epg coefficient of proportionality, depending on the characteristics of the electric drive of the welding head;
δ _{nej the} average calculated deviation for the j-th cycle of the real current-voltage characteristics from the reference.

The control action X _{NJ is} converted from digital to analog form and the received analog voltage signal is supplied to the analog input of the electric drive 26 for moving the welding head 100 in each Kth control cycle until that cycle of the (j + 1) -th cycle in which its new one is determined value.

где U_нэК текущее К-e значение напряжения между неплавящимся электродом и изделием из свариваемых деталей;
U_этК текущее К-e значение напряжения эталонной вольт-амперной характеристики для К-го значения тока;
m число измерений за интервал нарастания импульса тока.The deviation of the real volt-ampere characteristics from the reference (mismatch) is found by determining its average value by the formula:

where U _neK current K-e voltage value between the non-consumable electrode and the product from the welded parts;
U _etK current K-e voltage value of the reference volt-ampere characteristic for the K-th current value;
m is the number of measurements over the interval of rise of the current pulse.

The value of the mean deviation δ _{nej is} stored in the RAM cell of the memory unit 4. It may differ from the previous value δ _{ne (j-1)} calculated on the (j-1) -th control cycle. Until the end of the calculation of the average deviation in the current j-th cycle, the control action in each cycle was calculated based on the deviation δ _{ne (j-1) of the} previous cycle. These values of the deviation and the control action should be changed, which is performed at the next Kth measure of the current j-th cycle, which comes after the cycle at which the calculation of the deviation δ _{nej ended} . Then, using the formula (1), a new value of the control action X _{nej is calculated} , which is converted into an analog form and a new value of the analog signal is input to the input of the electric drive 26 in each control cycle until the calculation of new values of the average deviation and control action.

The features of the method are as follows. After arc excitation, after the time required for the formed weld pool to reach its steady-state dimensions, filler wire 102 is fed into the region of the anode spot 114 of arc 112 (Fig. 3) with the optimal speed V _pop and simultaneously the electrode 101 and filler wire 102 are moved direction of welding at a speed of V _St. The filler wire is fed into the anode spot of the arc due to the fact that the greatest amount of heat from the welding arc is generated in the anode spot and in this place the filler wire receives the maximum amount of heat from the weld pool. The optimal speed V _pop filler wire is selected from the following considerations. When the feed rate is less than optimal, a droplet mechanism of metal transfer of the filler wire is observed, since in this case it melts in the arc volume. This reduces the productivity of the welding process. At a feed rate much higher than the optimum, the filler wire does not have time to melt in the region of the anode spot of the arc, passes into the weld pool, may even bury itself in its bottom and bend, which leads to an excess of filler wire in the weld pool, and causes the appearance of fusion and metal inclusions, and ultimately to disruption of the welding process. There is a maximum permissible filler wire speed V _{p max} , which is (1.2-1.5) times greater than its optimum speed, at which the wire travels a longer path in the weld pool, but does not reach its bottom due to melting, which provides additional heating wire.

Thus, the optimal wire feed speed V _pop is characterized by the transition boundary of the transfer mechanism of the metal wire to drop metal.

From similar considerations, the optimal welding speed V _St.

Затем находят среднее отклонение мощности подогрева как разность некоторого опорного максимального значения мощности Q_{п зад}, определяемого условиями плавления присадочной проволоки, и средней мощности за цикл Q_пj:
δ_пj = Q_{п зад}-Q_пj (5)
Значение мощности Q_{п зад} имеет следующий физический смысл. Присадочная проволока, продвигаемая роликами механизма 104 подачи, по направлению к сварочной ванне с постоянной заданной скоростью V_{п зад}, нагревается проходящим по ней током I_пj до температуры плавления

Плавление проволоки происходит на ее конце, который почти касается сварочной ванны, но не доходит до нее на некоторую величину расстояния l_CD (см. фиг. 3, 4), которая может быть различной. Образующая на конце проволоки капля расплавленного металла отрывается от конца проволоки и под воздействием силы веса опускается в сварочную ванну. При этом в проволоке выделяется мощность Q_пj, от значения которой за цикл Q_пj и зависит величина дугового промежутка от конца проволоки до поверхности сварочной ванны l_CD. С увеличением мощности Q_пj величина l_CD увеличивается вследствие более быстрого расплавления проволоки, с уменьшением мощности Q_пj величина l_CD уменьшается.Simultaneously with operations to stabilize the length of the arc gap between the non-consumable electrode and the product, operations are performed to control the amount of electric power spent on heating the filler wire in one cycle. To do this, in each Kth step, the current i _pK and the voltage U _{pK of the} filler wire are measured along the leading edge of the synchronization pulse and the instantaneous power q _{pK is} determined as the product of current and voltage
q _pK = i _pK • U _pK (3)
Next, calculate the average heating power for the j-th cycle of N cycles by the formula:

Then find the average deviation of the heating power as the difference of some reference maximum value of power Q _{p back} , determined by the conditions of melting of the filler wire, and the average power per cycle Q _pj :
δ _pj = Q _{p ass} -Q _pj (5)
The value of power Q _{n ass} has the following physical meaning. The filler wire, promoted by the rollers of the feed mechanism 104, towards the weld pool with a constant predetermined speed V _{p ass} , is heated by the current I _pj passing through it to the melting temperature

The wire melts at its end, which almost touches the weld pool, but does not reach it by a certain distance l _CD (see Figs. 3, 4), which can be different. A drop of molten metal forming at the end of the wire is torn off from the end of the wire and lowered into the weld pool under the influence of a force of weight. In this case, the power Q _pj is released in the wire, the value of which for the cycle Q _pj determines the size of the arc gap from the end of the wire to the surface of the weld pool l _CD . With an increase in power Q _{pj, the} value of l _CD increases due to faster melting of the wire, with a decrease in power Q _{pj, the} value of l _CD decreases.

The value of power at which at a constant speed V _{p1 the} melted end of the filler wire is at a distance from the surface of the weld pool, equal to twice the diameter d _{p of the} wire, i.e.

l _CD 2d _p , (7)
is the reference setpoint Q _p Q _{p ass} . This power value is determined experimentally or by calculation.

The heating power of the wire is regulated by changing the heating current i _p as follows:
if δ _pj <0, then the wire current I _{p is} reduced;
if δ _pj > 0, then the wire current is increased;
if δ _pj = 0, then the current I _{p is} left unchanged.

For this, at each jth cycle, a control action X _{pj is generated} in digital form for the source of heating of the filler wire in accordance with the ratio
x _pj = k _p • δ _pj (8)
where X _pj control action applied to the input of the source of heating of the filler wire;
K _pp proportionality coefficient, depending on the characteristics of the transmission channel and the power source for heating the filler wire;
δ _{pj the} average calculated deviation for the j-th cycle of the real heating power from the reference set.

The control action X _{pj is} converted from digital to analog form and the received analog voltage signal is supplied to the analog input of the reference source 118 of heating from the output 122 of the digital-to-analog conversion unit 15 in each Kth control cycle until that cycle of the (j + 1) -th cycle, which will be determined by its new value.

The value of the average deviation δ _{pj is} stored in a special RAM cell of the memory unit 4. It may differ from the previous value of δ _{p (j-1)} calculated on the previous (j-1) -th control cycle. Until the calculation of the average deviation of the heating power in the current j-th cycle is completed, the control action X _{p (j-1)} calculated from the deviation δ _{p (j-1) of the} previous cycle was issued to the input of the heating source in each cycle. These values of the deviation and the control action should be changed, which is performed at the next Kth step of the current j-th cycle, which comes after the cycle at which the calculation of the deviation δ _{pj ended} . Then, using the formula (8), a new value of X _{pj is calculated} , which is converted into an analog form and a new value of the analog signal is input to the input of the source 118 of heating from the output 122 of the digital-to-analog conversion unit 15 in each Kth control cycle to the next cycle current (j + 1) of the cycle in which its new value will be determined, etc.

 As a result, even in the presence of a pulsating current of a non-consumable electrode, the mechanism for transfer of the filler metal from the wire to the weld pool does not change, i.e. stabilizes, which ensures high quality weld.

 The specified method can be implemented using various combinations of sets of technical means and the algorithms they implement. A general welding machine control algorithm is given, for example, in US Pat. No. 4,418,266; it displays in sufficient detail the control of all the functional mechanisms and units of the welding installation. The following is a description of the blocks of the algorithm corresponding to the flowcharts in FIG. 9, implemented on the proposed device and based on new, distinguishing features of the latter.

 Block 201: Beginning.

 This block corresponds to the launch of the main part of the control program, for example, by issuing the "start" command from the display keyboard.

 Block 202: Initialization.

 Microprocessor computing unit 2 performs an initial reset, initialization of all external devices and units and preparation of working memory cells, includes an interrupt system for microprocessor 3 and includes blocks 7, 12 and 16 that can cause interruptions, and then prohibits interruptions to the microprocessor.

 Block 203: "Setting the sign of the initial mode."

 In the corresponding bit R of the memory cell, “program status word” is entered 1, which indicates that the initial program mode is in progress. In addition, the synchronization interval counter is set to zero, i.e. K 0.

 Block 204: "Reception of system information."

The set initial values of the operating mode code, the value of the arc gap, the magnitude of the standby current, the amplitude of the pulse, the duration of the cycle T _c , the front of the current T _f , the heating power of the filler wire Q _{p back} , its feed speed V _{p back} , etc. are read by the microprocessor through parallel interface 6 and block 14 for inputting discrete signals on channels 49-77, 50-78, etc. from block 8 of the formation of tasks and coefficients or from RAM.

 Block 205: "Analysis of the mode code."

In bitwise analysis of the binary code of the operating mode of the installation and the control device, various branches of the algorithm can be implemented depending on the values of the bits of the specified mode code. For simplicity and certainty, the automatic operation mode is considered below, in which, among other functions, the average value of the power of the pulsating direct current of the filler wire is heated during the cycle T _c .

Block 206: "Installing the mechanisms and the welding torch in the initial position"
The microprocessor 3 of the control microcomputer 2 issues a sequence of commands to the interface unit 9 for switching the corresponding control circuits of the welding installation, setting the values of welding voltage and current, welding speed, filler wire feed speeds and welding torch movements along its axes of movement (not shown) . Then, the microprocessor gives a command to move the welding torch 100 to its initial position, the value of which l _dneo can either be selected from the memory unit 4, or set by the switches of the unit 8 forming tasks and coefficients.

Then, from the output 121 of the digital-to-analog conversion unit 15, a reference signal corresponding to a predetermined initial value of the velocity V _for filler wire feeding is output to the input of the power amplification unit 116 of the electric drive 117.

From the output 122 of the digital-to-analog conversion unit 15, the input voltage _source U of the idle wire U is supplied to the input of the filler wire heating source 118, which is necessary to initiate the arc when the wire 102 touches the surface of the welded product 21.

Полученное значение угла умножается на масштабный коэффициент K_α пересчета угла в код временного интервала, и результат записывается в ячейку ОЗУ текущего значения угла отпирания с именем CALP. Этот код далее в соответствии с алгоритмом будет выдан на информационный вход одного из программно-управляемых счетчиков (таймеров) блока 12.Block 207: "Determining the initial value of the unlock angle"
Given the value of the standby current I _ne1 , the initial value of the unlocking angle α ₁ is calculated for the next (K 1) synchronization interval

The obtained angle value is multiplied by the scale factor K _{α of} converting the angle into the time interval code, and the result is written into the RAM cell of the current unlock angle value with the name CALP. This code is further in accordance with the algorithm will be issued to the information input of one of the program-controlled counters (timers) of block 12.

 Block 208: Allow Interrupts.

 Since all the calculation and preparatory operations have been completed, a command is given to allow interruptions of microprocessor 3.

 Block 209: "Reset sign of the initial mode."

 This block and all subsequent ones belong to a cyclically repeating section of the program, in contrast to blocks 201.207 characterizing its initial section. In order to distinguish a cyclically repeating program section, the initial mode flag R in the program status word is reset (R: 0).

 Block 210: "Receiving system information."

 This block is identical to block 204, the only difference is that the microprocessor reads the current setpoint values of the system parameters of the selected operating mode of the welding machine and its control device, which can be changed by the operator at any time using the digital controllers of the unit 8 for generating tasks and coefficients.

 Block 211: "Analysis of the mode code."

 This block is identical to block 205, the difference is that it branches and exits to stop the microprocessor 3. When the operating mode code switch is set to the “operation” bit position (its designation “W”), the mode code is the output 49 of the block 8 of the formation of tasks and coefficients takes a zero value, which is perceived by the microprocessor 3 through the block 9 of the interface as a command to stop and stop the operation of the control device.

 Block 212: "Is a stop necessary?"

 The contents of the W bit "work" in the mode of operation read from the software switches are analyzed. If W 0, then the program proceeds to block 213, if W 1, then to block 214.

 Block 213: Stop.

 Since the W bit took a zero value, the program switched to this block. Here, the control program and the entire control device of the welding installation are stopped and the microprocessor enters the "Dispatcher" program to establish communication with the operator.

 Block 214: "Determining the number of measures in a loop."

Число тактов в цикле равно

Число тактов на интервале фронта Т_ф импульса тока равно

Блок 215: "Расчет следующего значения угла отпирания".Based on the given values of the cycle durations T _c , the front T _f , the top T _c , the fall T _c , the pause T _{p, the} program calculates the number of control cycles in each of these intervals by dividing any of these values by the duration of the control cycle, which is

The number of measures in the loop is

The number of ticks on the interval of the front T _f of the current pulse is

Block 215: "Calculation of the next value of the unlocking angle."

According to the set and current values of I _ne1 , I _ne2 , I _{neK, the} unlocking angle α _{K + 1} for the next valve of the three-phase power bridge in the arc power source is calculated by the microprocessor in accordance with the adopted regulation law. Then, the obtained value of the angle α _{K + 1} is multiplied by the coefficient K _{α /} conversion of the angle into the time interval code, and the result is placed in the CALP RAM cell, this code is subsequently issued in the subsequent program blocks to the information inputs of programmable timers.

Block 216: "There are signs of the requirement for calculating the deviations d _nej , δ _pj ?".

The presence of unit values of the DNJ and DPI attributes of the requirements for calculating deviations, respectively, δ _nej and δ _{pj, is analyzed successively} . If DNJ 0 and DPJ 0, then the deviation calculation is not required, and the program proceeds again to block 208. If DNJ 1 or DPJ 1, then the program proceeds to block 217.

 Blocks 217, 218: "Calculation of the deviation of the real IAC from the reference. Calculation of control actions."

Since the arrays of volt-ampere characteristics are collected, in accordance with formulas (2) and (1), the deviations δ _{nej of the} real V.A.H. are calculated. from the reference and control action of X _nej for the positional electric drive of the burner movement.

Then, according to formula (5), the average deviation δ _pj of the heating power of the filler wire is calculated and according to formula (8) of the control action X _pj for the source of heating of the wire.

 The calculation process may not fit into the remaining interval (Fig. 6) of the time of the current K-th control cycle, therefore, the calculations are performed in stages with the installation of special features indicating the completion of the calculation steps.

 Block 219: "Calculation of control actions over?".

According to the state of the last of the stage signs, it is determined whether the calculation of the control action X _nej or X _{pj is completed} . If this characteristic is equal to zero, then the program returns to the analysis of the previous stage signs. If it is equal to one, then the program proceeds to block 220.

 Block 220: "Set the signs of a change in the values of the control actions."

 In this block, the value of the XNJ RAM cell is replaced, the new value calculated in the previous block 219 is written to it. Then the DNJ flag (DNJ: 0) is reset. The sign GN is established of the requirement to issue a control action to the electric drive 26 (GN: 1).

Provided that the calculation of the control action X _pj is completed, the contents of the XPJ RAM cell are replaced, the new value calculated in the previous block 219 is written to it. Then the DPJ flag (DPJ: 0) is reset. The sign of GP is established for the requirement to issue a control action to the input of the filler wire heating source (GP: 1).

 Block 221: "Interruption from the synchronization pulse with the network."

 When any of the line voltages of the supply network reaches zero level (Fig. 6), the synchronization unit 7 with the network generates a narrow pulse at its pulse output 48, which is fed to the input of the controller unit 11 and fed to the output 41 of the unit through the galvanic isolation unit 100 9 interface and then to the input 34 of the parallel interface 16. This pulse with its leading edge acts on the interrupt system of the microprocessor 3, which enters the interrupt mode. At the same time, he proceeds to the interrupt service routine from synchronization pulses and, as the first of the operations, overwrites the contents of the microprocessor registers in the stacked RAM area of memory unit 4.

 Block 222: "Receiving a byte of information from the synchronization block. RESET GRAVES."

 The microprocessor 3, having received the interrupt signal, sets, in accordance with the program, in the ROM at the output 31 of the parallel interface 6 the address of the synchronization unit 7 with the network and sequentially generates a first “output” cycle and then an “input” cycle. The issued address is supplied to the input 38 of the interface unit 9 and then through the galvanic separation unit 100, the controller unit 11 to the input 75 of the passive discrete signal input unit 14, in which it is decrypted by the “output” signal, as a result, appears on the pulse output 79 of the unit 14 the strobe supplied to the input 46 of the block 7 synchronization with the network. By the input signal, the byte of input information comes from the information output 47 of the synchronization unit 7 with the network to the input 76 of the discrete passive signal input unit 14, and then through the controller unit 11, the galvanic separation unit 10 to the information input 29 of the parallel interface 6. At the same time, the pulse " input "on the input 46, the interrupt requirement trigger is reset in the synchronization unit 7 with the network and at the output 48 of the unit 7 a low voltage level appears, which is fed to the input 63, then through the controller unit 11 and the galvanic circuit unit 10 Thousands separator unit 41 to the output interface 9. As a result, the restoration of the low level at the input 34 “Requirement A” of the parallel interface 6 leads to the termination of the hardware interrupt mode and allows the microprocessor 3 to proceed to the next block of the interrupt service routine from null organs.

 Block 223: "Analysis of the input byte. Selecting the next valve. Starting the timer."

The microprocessor analyzes bit by bit the status code of the polarities of the phases of the line voltage of the network and determines from it the zone of which gate takes place at a given time. Next, a selection is made of the pair numbers of the next “switched on” and “confirmed” valves of the power thyristor bridge of the arc power source 22, i.e. it is determined which code should be displayed from block 6 to block 13 after working out the angle α _{to by the} corresponding counter. Then, in accordance with the number of the valve to be switched on, the number of the timer (software-controlled counter) to be loaded and started is selected. The timer number, which occupies two bits 07 and 06 in the 16-bit output control word, is assigned to the six-bit code of the switched pair of gates (bits 00. 05). The control word generated in this way is entered into the cell of the dynamic array (DM) of the output control words, and the contents of the pointer to the current address of the dynamic array are expanded, i.e. the word is placed in the next free RAM cell of the memory unit 4.

Then, a control code for block 12 of timers containing the address of the selected timer in the high bits 13 and 12 and the binary code of the time interval α _k from the CALP RAM cell in the lower bits is generated and transmitted via information channel 60.67. At the same time, an output signal is issued via control channel 62-69 of the block of timers 12, after which the selected timer is started.

 Block 224: "Receiving information about the value of the current of the welding arc."

 The microprocessor 3 through a parallel interface 6 issues to the interface unit 9 the address of channel 91, through which information from the signal converter 24 about the instantaneous value of the current of the welding arc of the non-consumable electrode is input, and a command to convert this analog signal. After the conversion is completed, block 17 issues a signal for the service requirement of the expansion valve, in response to the microprocessor it generates a signal BBB, which reset the signal expansion valve and reads the current code value of the welding arc.

Block 225: "Is the arc lit?"
In this block, by the magnitude of the current i _ne , an analysis is made whether the welding arc of the non-consumable electrode has been ignited. If the arc is ignited i _ne > 0, then the program proceeds to block 228. If i _ne 0, then the arc is not ignited, the program proceeds to block 226.

 Block 226: "Reset cycle counter."

 Since the arc was not ignited, welding on standby current did not start and a repeat of the procedure for turning on the valves of the power source is required. Therefore, the counter of control clock cycles is reset to K: 0. The flag for calculating the average deviations DNJ: 0 and DPJ: 0 is also reset. The flag for the formation of the front of the current pulse FI: 1 is set.

 Block 227: "Exit from interrupt to block 209".

 In this block, the microprocessor exits from the interrupt mode from the null organs of the synchronization unit 7 with the network, and the program proceeds to block 209.

 Block 228: "Receiving technological information."

The program switches to this block after block 225 in the presence of a non-consumable electrode arc current I _ne > 0. Similarly, the procedure for reading the current value, which is described above in block 224, the microprocessor reads the value of the arc voltage of the non-consumable electrode (NE) U _neK , current i _pK and voltage U _{pK of the} filler wire, and the obtained values of current and voltage are stored in the corresponding RAM arrays of the memory unit 4.

 Block 229: "Increase the measure of the clock."

 The control clock counter K is incremented by one. (K: K + 1).

Block 230: "Cycle j complete?"
An analysis of the code value in the counter of control clock cycles is carried out, whether it has reached the value N predefined in block 207, which characterizes the end of the jth cycle and the welding current pulse. If K <N, then the program proceeds to block 232. If K≥N, then to block 231.

 Block 231: "Reset the cycle counter. Go to the next cycle."

 Since the next j-th cycle is completed, the counter of control clock cycles is reset to K: 0. The program should go to the formation of the current pulse front of the next (j + 1) -th cycle. Therefore, the sign of the beginning of the formation of the front of the current pulse is set by FI: 1.

Block 232: "An array of m values is typed?"
An analysis of the code value in the counter of control clock cycles is carried out, whether it has reached the value m, predetermined in block 214, characterizing the end of the interval of the front of the current pulse. If K <m, then the program proceeds to block 234. If K≥m, then the formation of the front of the current pulse is completed, the program proceeds to block 233.

Block 233: "Setting the sign of the requirement to calculate the average deviation of the VAH"
The flag for the formation of the front of the current pulse FI is reset: 0. The flag for calculating the average value of the deviation δ _{nej is set} ; dynamic real wah from the reference v.a.kh. those. DNJ takes a value of one (DNJ: 1).

Block 234: "Calculation of the current deviation"
The calculation of the current deviation δ _{nec of the} dynamic real v.a.h. from the reference v.a.kh. according to the formula
δ = U _{NEC NEC} -U _et.k.
The result is added to the contents of the RAM cell with the name SUM, in which the sum of deviations δ _nec is accumulated in each control cycle.
Block 235: "Are there requirements for issuing control actions on the burner electric drive or heating source?"
The program analyzes the presence of single values of the GN and GP signs of the requirements for issuing control actions on the burner electric drive or heating source, respectively. If GN 0 and GP 0, then the program proceeds to block 238, if GN 1 or GP 1, then to block 236.

 Block 236: "The formation of the control words of the electric drive of the burner or source of heating."

The output control words are generated for block 15 of the digital-to-analog conversion, in the high bits of which the address of the corresponding output channel is placed, and in the lower bits of the control actions code is X _nej or X _pj , calculated in block 218 (see table).

 Block 237: "Issuance of control actions on the burner electric drive and heating source."

The microprocessor 3 provides the control word codes generated in the previous block 236 through the parallel interface 6 to the pairing unit 9 together with the airborne airborne signal. The control action code X _ney falls into the digital-to-analog conversion unit 15, is converted into an analog voltage signal in it, and from the output 84 of the block 15 is fed to the input of the burner moving electric drive 26. The movement mechanism 18 sets the burner to a new position, depending on the calculated deviation value δ _nej ..

 Then the sign GN of the requirement for issuing a control action is reset, i.e. GN takes a null value (GN: 0).

Similarly, the control action code X _pj falls into the digital-to-analog conversion unit 15, is converted into an analog voltage signal U _{p back} and is output from the block 122 output 122 to the input of the filler wire heating source 118, as a result of which new preset current values I _p and power Q _n heating filler wire. Then, the sign GP of the requirement for issuing a control action X _{pj is} reset (GP: 0).

 Block 238: "Issuing parameter values to the display."

For the convenience of the operator-welder, the basic values of the parameters are issued to the display devices, if any. Such parameters include T _c , T _f , δ _nej , X _nej , δ _pj , X _pj , etc. In this block, the microprocessor generates commands for their output.

 Block 239: "Exit from interrupt to block 209".

 In this block, the contents of the working registers are restored from the stack, the microprocessor leaves the interrupt mode from the null organs of the synchronization unit 7 with the network, and the program proceeds to block 209.

 Block 240: "Timer Interrupt".

 After starting, the selected timer starts to subtract from the initial code written in it in blocks 207, 215, one at a time, with the arrival of each clock pulse from the master high-frequency generator. After counting the time interval corresponding to the initial code at the time of zeroing, it acts through the priority block from the output 66 of the block 12 of the timers to the input 27 of the interrupt system of the microprocessor 3. The latter interrupts its work, analyzes the type of interrupt, determines that the interrupt has occurred from the block of 12 timers and switches to timer interrupt service routine, i.e. on this block 240.

 Block 241: "Reading the control word from the dynamic array."

 The microprocessor 3 reads the next control word from the RAM cell of the memory block 4 with the address CO M dynamic array.

 Block 242: "Turning on the selected pair of valves."

 In accordance with the code in bits 00.05 and the control word read from the dynamic array, the microprocessor generates pulses through blocks 6, 10, 11 to unlock the selected pair of valves. Block 13 distribution of unlocking pulses amplifies them and generates the corresponding voltage signals to the control electrodes of the included valve and the previous included valve to confirm the conductive state of the latter.

 Block 243: "Preparing the DM and reset the timer."

 Preparatory operations are performed in this block, since the information from the first DM cell with the name СО М is used, the contents of all its subsequent cells, starting from the second, are overwritten without change to neighboring cells with lower numbers, i.e. the array is shifted "forward" by one cell. After the shift, the contents of the current address pointer are reduced by 1 step.

 According to the information in bits 07 and 06 of the output control word, the program determines which of the three timers has finished counting the angle and caused the current interrupt, after which it resets the interrupt trigger of this timer by the pulse input signal issued by the microprocessor unit on channel 32-68.

 Block 244: "Removing the unlock pulses."

 Since the next pair of gates is turned on by the unlocking pulses issued in block 242, the microprocessor issues a zero code in bits 00.05 through the parallel interface 6, blocks 10 and 11, in accordance with which block 13 removes voltage pulses from the control electrodes of the included valve pair.

 Block 245: Exit Interrupt.

 The microprocessor exits the interrupt mode from the block 12 of program-controlled counters, and the program returns to the command before which the interrupt occurred.

 With the arrival of a synchronization pulse from the next, null-organ of block 7, the entire cycle of the microprocessor device for controlling the arc welding process is repeated according to the block diagram of the algorithm from block 221 through the interrupt routine from zero-organs (blocks 222.239), then through blocks 209.220 of the main programs and then the interrupt routine (blocks 240, 245) from the timer block for the zone of the next included valve.

 Thus, in comparison with the prototype, the proposed technical solution allows to improve the quality of the weld and expand the technological capabilities of automatic welding by ensuring the maintenance of the length of the arc gap when welding in pulsating DC modes with filler wire by periodically taking the current-voltage characteristics of the arc in the rise interval welding current in each pulse, determining the average value of its deviation from the reference current-voltage characteristics at a pace e with the process, the formation at the pace with the process of the corresponding control signal and the impact on the electric drive of the burner with the electrode to automatically achieve a minimum of mismatch. The specified sequence of operations is performed automatically and synchronously with the alternating voltage of the industrial supply network without the participation of a human operator. High stability of the synchronization of the control process provides increased accuracy and stability of the welding process, which improves the quality of the welded joint. The introduced operation of automatic control and regulation of current, voltage and power in accordance with the proposed method and the elimination of errors of the operator-welder reduces the complexity of the production of welded joints.

Claims (1)

1 Device for controlling the process of arc welding with a non-consumable electrode in a shielding gas medium, comprising a welding unit controlling a microcomputer, a synchronization unit with a network, a unit for generating tasks and coefficients, and an interface unit made in the form of a galvanic separation unit, a controller unit, a timer unit, a distribution unit and amplification of unlocking pulses, a discrete signal input unit, a digital-to-analog conversion unit, an analog signal switching unit, and an analog-to-digital conversion unit, interconnected by information buses of input and output of discrete information, buses of pulse control signals “Input” and “Output”, in which the analog signal switching unit with the first and second inputs is connected to the outputs of the matching converters of the current signal and the arc voltage signal of a non-consumable electrode, the digital-analog block output conversion is connected to the input of the welding torch of the welding unit, the information output of the distribution unit and amplification of unlocking pulses is connected to the power source arc welding non-consumable electrode, characterized in that, in order to expand the technological and functional capabilities of the device by adjusting the feed speed and heating temperature of the filler wire and control the input electric power, the welding unit is equipped with a mechanism and electric feed filler wire with a control input, the source of heating of the filler wire with a control input, power inputs and two output terminals, a shunt and a second matching current transformer the second matching voltage signal converter, the analog signal switching unit is additionally equipped with third and fourth analog inputs, and the digital-to-analog conversion unit has second and third analog outputs, the power inputs of the heating source being connected to the industrial power network, the first power output terminal being connected to the output terminal of the device and the second through the shunt to the current collector of the welding installation, the measuring output of the shunt is connected to the input of the second matching Converter the current signal, the output of which is connected to the third input of the analog signal switching unit, the second output of the digital-to-analog conversion unit is connected to the input of the frequency setting of the filler wire electric drive, the third output of the digital-to-analog conversion unit is connected to the control input of the filament wire heating source, the inputs of the second matching voltage signal converter connected to the output terminal of the device and the current collector, and the output to the fourth input of the switching unit analog signals.

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