RU2251474C1 - Apparatus for automatic control of welding head position - Google Patents

Abstract

FIELD: automatization of welding processes, namely electric arc gas-shield welding of dressed and angular seams under flux.

SUBSTANCE: first circuit for controlling welding head position includes connected in series electric arc power source 1, welding circuit shunt 2; welding current value pickup 3, band filter 4 tuned for oscillation frequency of electrode, timing detector 5, low frequency filter 6. Second inlet of detector 5 is connected to scanning phase pickup 7 whose inlet is connected to oscillator 8 connected to welding head 9. First adder 10, fiat amplifier 11 and drive unit for moving head across butt are connected in series. Second circuit for controlling position of welding head includes connected in series welding voltage pickup 13, Schmitt trigger 14, first inverter 15, analog switch 16 whose control inlet is connected to outlet of scanning phase pickup 7. Two outlets of analog switch 16 are connected to respective inlets of first 17 and second 18 first-order delay units. Outlets of said units are connected to respective inlets of unit 19 for comparing analog signals whose outlet is connected through smoothing filter 20 to second inlet of first adder 10. Outlet of first adder 10 through first amplifier 11 is connected to drive unit 12 for moving head across butt. Circuit for controlling motion speed of welding head along butt includes connected in series rectifier 21, second inverter 22, second adder 23, second amplifier 24, drive unit 25 for feeding welding head along butt, reference voltage setter 26. Inlet of rectifier 21 is connected to outlet of first adder 10. Second inlet of second adder 23 is connected to reference voltage source 26.

EFFECT: enhanced quality of welded joint.

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Description

The alleged invention relates to the field of automation of welding processes, more specifically to the automation of electric arc welding of cut and fillet welds in a shielding gas environment and submerged arc. It can find application in mechanical engineering and instrument making.

Until now, most of the processes of electric arc welding are carried out manually, require a highly qualified welder and can be automated in mass production only under the condition of high-quality cutting of seams and high accuracy of installation of parts in relation to the welding stand. This is due to the fact that in order to obtain a high-quality weld, all other things being equal, continuous alignment of the axis of the burner with the middle of the joint at non-planar joints (convex or concave) is necessary. Thus, this combination is the main condition for the automation of the electric welding process.

There are a number of devices for pointing the electrode to the joint of the welded edges using the arc as a sensing element (see Timchenko VA and other Systems of automatic guidance of the electrode on the connection line using the arc as a sensor // Automatic welding. - 1981. - N 6. - p. 59-64).

A device for controlling the movement of the welding head relative to the axis of the joint during the mechanized welding process, comprising a sensor for welding current (or voltage), an arc deflection sign sensor, analogue integrators, a control circuit, a welding torch movement drive across the joint and a control circuit for this drive (FRG patent No. 2533448 , published on January 27, 2017, IPC ⁵ В 23 К 9/10).

The disadvantage of this device is that when the bend of the weld at the beginning of the bend, the connection becomes less quality.

The closest in technical essence is the device for automatic control of the position of the welding head, containing the first channel for controlling the position of the welding head, which includes a series-connected arc power source, a shunt of the welding circuit, a welding current sensor, a band-pass filter tuned to the electrode oscillation frequency, and a synchronous detector , a low-pass filter, the second input of the synchronous detector is connected to the output of the scanning phase sensor, the input of which is connected to the oscillator, connected to the welding head, a serially connected amplifier and a head moving drive across the butt, a second channel for controlling the position of the welding head, containing a welding voltage sensor in series, a Schmidt trigger, an analog key, the control input of which is connected to the output of the scanning phase sensor, two outputs of the analog key are connected to the corresponding inputs of the first and second inertial links of the first order, the outputs of which are connected to the corresponding inputs of the comparison device ana Ogove signals, whose output is connected via the smoothing filter to the first input of an adder, to the second input of which is connected to the output of low pass filter, and an adder output connected to an input of the amplifier (RF patent №2177860, IPC ⁷ B 23 K 9/10, BI No. 1, 2002).

The objective of the invention is to improve the quality of the welded joint.

This object is achieved in that in a known device containing a scanning phase sensor, the input of which is connected to an oscillator connected to the welding head, the first adder, the first amplifier, the drive moving the head across the joint, the first channel for controlling the position of the welding head, including the series connected arc power source, welding circuit shunt, welding current sensor, band-pass filter tuned to electrode oscillation frequency, synchronous detector, fil low frequency channel, a second channel for controlling the position of the welding head, including a series-connected welding voltage sensor, a Schmidt trigger, an analog key, first and second inertial links of the first order, an analog signal comparison device, a smoothing filter, the second input of a synchronous detector and an analog key control input connected to the output of the scanning phase sensor, the output of the low-pass filter and the output of the smoothing filter are connected to the first and second inputs of the first adder, different the fact that the first and second inverters, a rectifier, a second adder, a second amplifier, a welding head feed drive along the joint, a reference voltage adjuster are introduced into the device, the rectifier, a second inverter, a second adder, a second amplifier and a welding head feed drive along the junction are connected in series, the reference voltage adjuster is connected to the second input of the second adder, the rectifier input is connected to the output of the first adder, and the input of the first inverter is connected to the Schmidt trigger output, and the output to analog my key.

In the device for automatic control of the position of the welding head, a band-pass filter, a low-pass filter, an adder, a synchronous detector, an amplifier, an inverter, a drive, a scanning phase sensor, a welding current sensor, a welding voltage sensor, an analog signal comparison device, a smoothing filter, a Schmidt trigger, inertial links first-order, an analog switch, a reference voltage regulator, a power source, an oscillator are used for their intended purpose and are known in electrical engineering. However, the combination of compounds indicated above was not found in the patent and scientific literature.

The essence of the invention is illustrated in the drawing, which shows a structural diagram of a device for automatically controlling the position of the welding head.

The device for automatic control of the position of the welding head contains a first channel for controlling the position of the welding head, including a serially connected arc power source 1, a shunt of the welding circuit 2, a welding current sensor 3, a band-pass filter 4 tuned to the electrode oscillation frequency, a synchronous detector 5, a low-pass filter 6, the second input of the synchronous detector 5 is connected to the output of the scanning phase sensor 7, the input of which is connected to the oscillator 8 connected to the welding head 9, in series with The first adder 10, the first amplifier 11, the actuator moving the head across the joint 12, the second channel for controlling the position of the welding head, containing the welding voltage sensor 13 connected in series, the Schmidt trigger 14, the first inverter 15, the analog switch 16, the control input of which is connected to the sensor output scanning phase 7, two outputs of the analog key are connected to the corresponding inputs of the first 17 and second 18 inertial links of the first order, the outputs of which are connected to the corresponding inputs of the device I analog signals 19, the output of which is connected through a smoothing filter 20 to the second input of the first adder 10, the output of the first adder through the first amplifier 11 is connected to a drive 12 for moving the welding head 9 across the joint, a channel for controlling the speed of movement of the welding head along the joint, containing a rectifier connected in series 21, the second inverter 22, the second adder 23, the second amplifier 24 and the welding torch feed drive 25 along the junction, the input of the rectifier 21 being connected to the output of the first adder 10, and to the second the input of the second adder 23 is connected to the reference voltage adjuster 26.

A device for automatically controlling the position of the welding head operates as follows.

Oscillator 8 vibrates the welding head 9 relative to the joint of the parts to be welded. When the welding head deviates from the joint in the welding current, harmonic components of different frequencies appear, which are removed from the welding current sensor 3 connected to the welding shunt 2. The first harmonic component is selected by a band-pass filter 4, rectified by a synchronous detector 5 taking into account the signal from the phase 7 sensor scan. As a result, a rectified signal of a certain polarity is formed at the output of the synchronous detector 5, depending on the direction of deviation of the welding head from the joint. This signal is smoothed out by a low-pass filter 6 and fed to the first input of the first adder 10. From the arc source 1, through the welding voltage sensor 13 and Schmidt trigger 14, a rectangular short-circuit signal is supplied to the input of the analog switch 16 through the first inverter 15. In accordance with the signal scan phase sensor 7, the analog switch is switched either to the input of the first inertial link of the first order 17, or to the input of the second inertial link of the first order 18. In the device for comparing analog signals 19 from From the output of the first inertial link of the first order 17 and the signal from the output of the second inertial link of the first order 18, an error signal is generated and, having passed the smoothing filter 20, is fed to the second input of the first adder 10. From the output of the first adder 10 to the drive 12, the head moves across the joint through the first amplifier 11 receives a signal for correcting the position of the welding head. As a result, the welding head begins to move towards the joint line.

When the junction path deviates, the first adder 10 receives the error signals from the low-pass filter 6 and the smoothing filter 20, the output signal from the first adder 10 increases, passes through the rectifier 21 and the second inverter 22, and enters the second adder 23, to the second input of which the reference voltage 26 is supplied with a reference voltage. Therefore, when the joint is bent, the output signal from the second adder 23, which passes through the second amplifier 24 to the feed drive 25 of the welding head 9 along the joint, decreases and the welding head slows down, due to which the weld pool is filled more efficiently. After working off the joint deflection system, at the output of the low-pass filter 6 and the smoothing filter 20, the signal is zeroed and the speed of the welding head 9, determined by the value of the reference voltage, is restored.

Thus, in comparison with the prototype of the proposed device provides a better filling of the weld pool when bending the weld.

Claims (1)

A device for automatically controlling the position of the welding head, comprising a scanning phase sensor, the input of which is connected to an oscillator connected to the welding head, a first adder, a first amplifier, a drive moving the head across the joint, a first channel for controlling the position of the welding head, including an arc power source connected in series , welding circuit shunt, welding current sensor, band-pass filter tuned to the electrode oscillation frequency, synchronous detector , a low-pass filter, a second channel for controlling the position of the welding head, including a series-connected welding voltage sensor, a Schmidt trigger, an analog key, first and second inertial links of the first order, an analog signal comparison device, a smoothing filter, the second input of a synchronous detector and an analog control input keys are connected to the output of the scanning phase sensor, the output of the low-pass filter and the output of the smoothing filter are connected to the first and second inputs of the first adder, from characterized in that the first and second inverters, a rectifier, a second adder, a second amplifier, a welding head feed drive along a joint, a reference voltage adjuster are introduced into the device, the rectifier, a second inverter, a second adder, a second amplifier and a welding head feed drive along a joint are connected in series, the reference voltage adjuster is connected to the second input of the second adder, the rectifier input is connected to the output of the first adder, and the input of the first inverter is connected to the Schmidt trigger output, and the output to the anal govomu key.