JP5756298B2 - Welding power supply and welding machine - Google Patents

Description

  The present invention relates to a welding power source apparatus that performs feedback control based on calculation of an electrode tip voltage and a welding machine including the welding power source apparatus.

  For example, as disclosed in Patent Document 1, the arc welding power source device converts DC power obtained by rectifying AC input power from a commercial power source into high-frequency AC power using an inverter circuit, and the voltage is adjusted by a welding transformer. The high frequency AC power is converted into DC output power suitable for arc welding by a rectifier circuit and a DC reactor. The output power generated by the power supply device is supplied to the electrode supported by the torch, whereby an arc is generated between the electrode tip and the welding target, and welding of the welding target is performed.

  Further, such a welding power supply device detects the output current and the output voltage, and the control device feeds back the output current and output voltage detected at that time to the PWM control of the inverter circuit. Improvement of welding performance is aimed at by carrying out control which makes the output electric power of an appropriate value.

JP-A-8-103868

  By the way, in order to generate a suitable arc, not only the output voltage detected in the power supply device is reflected in the control value of the inverter circuit but also the tip voltage of the electrode where the arc is generated is calculated and calculated. It is preferable to reflect the measured electrode tip voltage in the control value.

  This is because, in practice, the torch (electrode) for welding and the power supply device are often separated from each other, and the two are generally connected via a power cable. is there. Therefore, since the cable length of the power cable differs for each user, not only the resistance value of the cable itself is different, but also when the cable is laid in a straight line, for example, when the cable is laid around the extra length, for example, And the inductance value varies depending on the number of laps. For this reason, in order to further improve the welding performance, the voltage variation of the resistance and the inductance between the power cable and the electrodes outside the power supply device cannot be ignored.

  Therefore, in the aspect in which the output voltage detected in the power supply device is reflected in the control value of the inverter circuit, the voltage value deviating from the true electrode tip voltage is reflected in the control value of the inverter circuit. There is a concern that it may hinder the generation of a suitable arc and hinder further improvement in welding performance.

  When measuring the resistance value and the inductance value used for the calculation of the electrode tip voltage, an operation such as a state in which the electrode tip is short-circuited is required. Therefore, it is desirable that the worker be near the electrode tip. On the other hand, if the operation at the time of measurement is set to be possible only on the power supply side, especially if the power supply is only horizontally with respect to the electrode part, It was difficult for an operator near the tip to operate the power supply device.

  The present invention has been made in order to solve the above-described problem, and the purpose thereof is welding capable of easily measuring the resistance value and the inductance value used for calculating the electrode tip voltage regardless of the installation state. A power supply device for welding and a welding machine provided with the power supply device for welding are provided.

In order to solve the above-mentioned problems, an invention according to claim 1 is directed to an inverter circuit that converts DC power into high-frequency AC power, a welding transformer that adjusts the voltage of the converted AC power, and a secondary side of the welding transformer. DC conversion means for generating DC output power suitable for welding from AC power, and generating an arc for welding with the welding object based on supply of the generated output power to the electrode The tip voltage of the electrode is calculated based on the output current and the output voltage detected by the detection means provided in the power line on the output side of the rectifier circuit provided in the DC conversion means in the apparatus, A welding power supply device further comprising a control means for controlling the inverter circuit based on the calculated tip voltage, wherein the electrode is short-circuited and is generated by the operation of the inverter circuit The resistance value calculating means for calculating the total resistance value on the path to the electrode tip based on the voltage value of the output voltage when the output current is a predetermined current value, and the electrode is short-circuited, And an inductance value calculating means for calculating a total inductance value on the path to the tip of the electrode based on a current attenuation amount when the output current generated by the operation of the inverter circuit is a predetermined current value. Having a measurement mode, and correcting the voltage change applied to the total resistance value and the total inductance value on the path to the electrode tip with respect to the voltage value of the output voltage detected by the detection means, A tip voltage calculating means for calculating a voltage; a torch for supporting and feeding the electrode; and the electrode is a wire electrode, and the electric In addition to the original corresponding operation of the operated switch based on the prescribed operation using at least one switch among the various operation switches provided in each of the operation remote controllers provided in the wire supply device for feeding The gist of the invention is that it comprises switching means for switching the measurement mode to be executable.

  According to the present invention, when switching to the measurement mode for measuring the total resistance value and the total inductance value up to the electrode tip for calculating the electrode tip voltage, the torch and the operation remote controller of the wire supply device are provided respectively. By selectively operating at least one of the various operation switches, switching to the measurement mode is performed separately from the original corresponding operation of the operated switch. In other words, by using a switch that is originally provided in a torch or operation remote controller to perform another operation, it is not necessary to separately provide a switch for performing measurement, and the torch and operation remote control switches in the vicinity of the electrodes are defined. By the operation, it is possible to easily perform the measurement while confirming the state of the electrode tip portion during the measurement. In addition, this makes it possible to easily perform measurement even in the installation state of the power supply device itself that is far away from the electrode.

  According to a second aspect of the present invention, in the welding power source device according to the first aspect, the torch is provided with a torch switch, and the operation remote controller is provided with an inching switch, and the torch switch and the inching switch are combined. The inching operation of the electrode is performed based on the ON operation, and the switching means switches to the measurement mode based on the prescribed operation combining the torch switch and the inching switch. To do.

  In the present invention, at the time of switching to the measurement mode, the operation for performing the inching operation combining the torch switch and the inching switch of the operation remote controller is defined as a prescribed operation such as operating a predetermined number of times within a predetermined time. Thus, it is possible to easily switch to the measurement mode by an operation using both switches.

  According to a third aspect of the present invention, in the welding power supply device according to the second aspect, the switching means is based on a prescribed operation of at least one of the torch switch and the inching switch at the end of the measurement mode. The gist is to perform the termination.

  In the present invention, at the end of the measurement mode, the measurement mode is ended by operating the same torch switch or inching switch operated at the time of switching (starting) to the previous measurement mode. Operation at the end is also easy.

According to a fourth aspect of the invention, in the welding power supply device according to claim 2 or 3, wherein the distal end portion of the torch provided with a contact tip for feeding power to the electrode, in the measurement mode, the Instead of directly short-circuiting the electrode, the contact chip is in a short-circuited state, and the switching means is switched to the measurement mode based on the prescribed operation in combination of the torch switch and the inching switch, The gist of the invention is to house the electrode protruding in the inching operation as an original corresponding operation by operating both the switches in the contact chip.

  In the present invention, when switching to the measurement mode, the original corresponding operation based on the prescribed operation combining the torch switch and the inching switch, that is, the electrode protruding by the inching operation is switched to the measurement mode by the prescribed operation. Housed in the contact tip at the tip of the torch. Thereby, when the electrode is short-circuited at the time of measurement, the contact tip at the tip of the torch is brought into contact with the mating member to make the electrode pseudo-short-circuited easily without requiring a separate operation. It becomes possible.

  The gist of the invention according to claim 5 is the welding power source device according to claim 4, wherein the switching means causes the electrode to protrude from the contact tip by a predetermined amount when the measurement mode ends. .

  In the present invention, the electrode housed in the contact tip at the tip of the torch at the time of switching to the measurement mode is protruded by a predetermined amount from the contact tip at the end of the measurement mode. Thereby, it is possible to easily shift to a welding operation performed by projecting the electrode.

  Invention of Claim 6 controls the inert gas discharge | released from the front-end | tip part of the said torch at the time of the said welding power supply apparatus in any one of Claims 1-5, The gist of the invention is that the gas emission sound is used as an abnormality notification means for notifying an abnormality during actual measurement in the measurement mode.

  In this invention, when notifying the abnormality at the time of actual measurement in the measurement mode, the operator is notified using the sound of the gas released from the tip of the torch. That is, in a welding machine that performs welding using an inert gas, it is possible to easily and reliably notify an operator who is near an electrode farther away from the power supply device without separately using a means for notifying that effect. It becomes possible.

A seventh aspect of the present invention is a welding machine configured to include the welding power supply device according to any one of the first to sixth aspects.
According to the present invention, it is possible to provide a welding machine capable of easily measuring the resistance value and the inductance value regardless of the installation state of the power supply device.

  According to the present invention, it is possible to provide a welding power source device that can easily measure the resistance value and the inductance value used for calculating the electrode tip voltage regardless of the installation state, and a welding machine including the welding power source device. can do.

It is a block diagram which mainly shows the power supply device in the arc welding machine of this embodiment. It is explanatory drawing for demonstrating the change of an inductance value. It is explanatory drawing for demonstrating the calculation method of resistance value and an inductance value. It is a block diagram of the arc welding machine used for description of switching operation to a measurement mode. It is a timing diagram used for description of switching operation to a measurement mode.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
FIG. 1 shows a consumable electrode type arc welding machine 10. In the arc welding machine 10, the wire electrode 12 supported by the torch TH is connected to the plus side output terminal of the welding power source device 11, the welding object M is connected to the minus side output terminal of the power source device 11, and the power source Arc welding is performed by supplying the DC output power generated by the apparatus 11 to the wire electrode 12. At this time, since the wire electrode 12 is consumed during welding, the wire supply device 13 feeds the wire electrode 12 according to the consumption. Output power is supplied to the wire electrode 12 and the welding target M via a power cable 14 connected to the output terminal of the power supply device 11.

  The welding power source device 11 converts three-phase AC input power supplied from a commercial power source into DC output power suitable for arc welding. The AC input power is converted into DC power by a rectifying / smoothing circuit 21 including a diode bridge and a smoothing capacitor, and the converted DC power is converted into high-frequency AC power by an inverter circuit 22. The inverter circuit 22 is configured by a bridge circuit using four switching elements TR such as IGBTs, and PWM control by the control device 31 is performed.

  The high-frequency AC power generated by the inverter circuit 22 is converted to secondary AC power adjusted to a predetermined voltage value by the welding transformer 23. The secondary side AC power of the welding transformer 23 is converted into DC output power suitable for arc welding by a rectifier circuit 24 using a diode and a DC reactor 25.

  A supersaturated reactor having supersaturation characteristics is used for the direct current reactor 25 of the present embodiment. As shown in FIG. 2, the characteristic of the DC reactor 25 is a normal characteristic region A1 in which a high current region that is larger than a predetermined current value Ia including the current value Ip1 is constant at a minimum necessary inductance value La. On the other hand, the low current region where the current value is equal to or less than the predetermined current value Ia is a supersaturation characteristic region A2 in which the inductance value gradually increases linearly as the current value decreases (inductance value Lb at the current value Ip2). In other words, by using the DC reactor 25 having such characteristics, since the inductance value is small in the high current region, the influence on the waveform control for current smoothing is small, and in the low current region, the inductance value is increased to increase the arc. A suitable DC output power is generated over the entire current region so that disconnection is prevented.

  As shown in FIG. 1, the control device 31 performs PWM control on the switching element TR of the inverter circuit 22 to control the DC output power to an appropriate value from time to time. At this time, the control device 31 detects the output current I and the output voltage V from time to time, and performs feedback to the PWM control based on the detected output current I and output voltage V.

  That is, the current sensor 33 is provided on the power supply line of the negative output terminal in the power supply device 11, and the control device 31 outputs the output current I of the power supply device 11 via the current sensor 33 in the processing unit (CPU) 32. Is detected. A voltage sensor 34 is provided between the power supply lines immediately after the rectifier circuit 24, and the control device 31 detects the output voltage V of the power supply device 11 through the voltage sensor 34 in the processing unit 32. The control device 31 calculates the duty of the PWM control based on the output current I and the output voltage V detected at that time by the processing unit 32 and generates a PWM control signal to be output to the inverter circuit 22.

  Here, in the PWM control, it is preferable to use the tip voltage Va of the wire electrode 12 at which an arc is generated as the output voltage V used for the control, but it is difficult to directly detect the tip voltage Va. Therefore, the control device 31 holds in advance a voltage change between the voltage sensor 34 and the electrode 12 in a storage device (not shown), and corrects the voltage change to the output voltage V detected at that time. The tip voltage Va is obtained to perform PWM control using the calculated tip voltage Va.

  By the way, the voltage change between the voltage sensor 34 and the electrode 12 includes the voltage change in the power supply device 11 (voltage change due to the resistance value R1 and the inductance value L1 from the rectifier circuit 24 to the output terminal), the external Voltage variation (voltage variation due to the resistance value R2 and the inductance value L2 from the output terminal to the tip of the electrode 12 via the power cable 14). Since the internal voltage change of the power supply device 11 is not affected by the use state, it can be incorporated in the calculation of the tip voltage Va as a correction term in advance. Since the conditions are different for each user such as the laying state (straight line laying, round laying, and the number of laps), it is greatly affected by the change in the resistance value R2, particularly the inductance value L2.

  Therefore, when the user installs the arc welding machine 10 on the site and puts it in a state of use including the installation of the power cable 14, the internal resistance value R1 and the inductance value L1, and the external resistance value R2 and the inductance value. A resistance value R and an inductance value L obtained by adding up L2 are measured. The measured total resistance value R and total inductance value L are held in the control device 31.

  Note that the power supply device 11 of the present embodiment is provided with a measurement mode for executing processing for measuring the total resistance value R and the total inductance value L. The control device 31 can shift to the measurement mode based on the input). Incidentally, at the time of measurement in the measurement mode, the wire electrode 12 needs to be short-circuited with the welding object M, but in this embodiment, the wire electrode 12 is directly short-circuited to the welding object M as shown in FIG. First, the contact tip THa, which is provided at the tip of the torch TH and supplies power to the wire electrode 12, is short-circuited to the welding object M. In this case, a special jig for short circuit may be produced and used.

  The measurement mode will be described in detail. As shown in FIG. 3, first, the inverter circuit 22 is operated to increase the output current I to the current value Ip1. This current value Ip1 is a current value in the normal characteristic region A1 that is constant at the inductance value La in a single DC reactor 25 having supersaturation characteristics. Actually, as shown in FIG. 2, the characteristic is offset depending on the laying state of the power cable 14 and the total inductance value L is constant at the offset value La1, but the normal characteristic region A1 in consideration of the offset is also provided. Set to current value. And the average voltage value Ve in the area hold | maintained with such electric current value Ip1 is measured. Thereby, first, the total resistance value R is calculated by the following equation (a).

R = Ve / Ip1 (a)

Next, the operation of the inverter circuit 22 is stopped, and time measurement is started from the time T0 at this time. At the same time, sampling of the output current I that changes every moment from the time T0 is performed, and the time when the current value ΔIp1 (Ip1 × 36.8%) corresponding to the time constant is reached is defined as T1, A time (time constant) τ1 between times T1 and T0 is obtained. Thereby, the total inductance value La1 (inductance value La in the case of the reactor 25 alone) that changes in the normal characteristic region A1 is calculated by the following equation (b).

La1 = R · τ1 (= Ve · τ1 / Ip1) (b)

Next, the inverter circuit 22 is operated again, and the output current I is adjusted to a predetermined current value Ip2 in the oversaturation characteristic region A2. After the adjustment, the operation of the inverter circuit 22 is stopped again, and time measurement is started from time T2 at this time. At the same time, the sampling of the output current I that changes every moment from the time T2 is performed, and the time when the current value ΔIp2 (Ip2 × 36.8%) that becomes the current attenuation corresponding to the time constant is reached is defined as T3. A time (time constant) τ2 between times T3 and T2 is obtained. Thereby, the total inductance value Lb1 (inductance value Lb for the reactor 25 alone) that changes in the supersaturation characteristic region A2 is calculated by the following equation (c).

Lb1 = R · τ2 = (Ve · τ2 / Ip2) (c)

Next, as shown in FIG. 2, the calculated total inductance value La1 of the normal characteristic region A1 and the total inductance value Lb1 of the supersaturated characteristic region A2 are linearly complemented, so that the total inductance value L is a function L (I) of the current I. As obtained. The function L (I) of the total inductance value L obtained in this way and the total resistance value R obtained previously are held in the control device 31. This completes the measurement mode.

And the control apparatus 31 is calculating the front-end | tip voltage Va by following Formula (d) from the output current I and the output voltage V at the time of welding operation.

Va = V−L (I) · dI / dt−RI (d)

Incidentally, in terms of specific numerical values, when the inverter circuit 22 is turned on, the current value Ip1 = 400 [A] of the output current I is output for 10 [ms], and then the inverter circuit 22 is turned off. If the average voltage value Ve during this time is 4 [V], from the above equation (a),

R = Ve / Ip1 = 4/400 = 0.01 [Ω]

And the total resistance value R is calculated.

Next, the current value ΔIp1 at which the current value Ip1 is a current attenuation amount corresponding to the time constant τ1 is

ΔIp1 = 400 × 0.368 = 147 [A]

If the time constant τ1 for reaching the output current I from 400 [A] to 147 [A] after turning off the inverter circuit 22 is 3 [ms], the above equation (b)

La1 = R · τ1 = 0.01 × 3 = 0.03 [mH]

In the normal characteristic region A1, the total inductance value La1 including the single inductance value La of the DC reactor 25 is calculated. The current value Ip1 described above needs to be estimated from the specifications of the DC reactor 25 used in advance and set to a value that does not reach the oversaturation characteristic region A2.

Next, the inverter circuit 22 is turned on again, and the output current I is output for 10 [ms] as a current value Ip2 = 20 [A] corresponding to the minimum current of the arc welding machine 10 in the supersaturation characteristic region A2, for example. Then, the inverter circuit 22 is turned off. The current value ΔIp2 at which the current value Ip2 is a current attenuation amount corresponding to the time constant τ2 is

ΔIp2 = 20 × 0.368 = 7 [A]

If the time constant τ2 at which the output current I reaches 7 [A] from 20 [A] after turning off the inverter circuit 22 is 10 [ms], the above equation (c)

Lb1 = R · τ2 = 0.01 × 10 = 0.1 [mH]

In the supersaturation characteristic region A2, the total inductance value Lb1 including the single inductance value Lb of the DC reactor 25 is calculated.

  Then, by performing linear interpolation of La1 = 0.03 [mH] and Lb1 = 0.1 [mH], a function L (I) of the total inductance value L is obtained, and the previously obtained total resistance value R Thus, the tip voltage Va at that time can be calculated from the above equation (d). In addition, the specific numerical value quoted above is an example, and is not limited to this.

  Since the tip voltage Va is appropriately calculated even in the welding power supply device 11 of the present embodiment using the DC reactor 25 having the supersaturation characteristic in this way, an inverter based on the tip voltage Va that is appropriately calculated. The occasional control of the circuit 22 is more appropriately performed. Therefore, the synergistic effect with the use of the reactor 25 having the supersaturation characteristic enables generation of more appropriate DC output power for arc welding over the entire current region.

  The transition to the measurement mode described above is performed based on the operation of an operation switch (not shown) provided in the power supply device 11. In the present embodiment, as shown in FIG. 4, the torch switch (torch provided in the torch TH). SW) 41 and the operation remote controller 42 provided in the wire supply device 13 are used, and the operation can be shifted even from an operation away from the power supply device 11.

  The torch TH is provided with a trigger type torch switch 41 that is turned on by pulling. The torch switch 41 supplies power to the wire electrode 12 when the operator manually turns on to start welding. Further, the torch switch 41 is operated together with an after-mentioned inching switch (inching SW) 42c provided in the operation remote controller 42, whereby the inching operation of the wire electrode 12 is performed. Specifically, when the torch switch 41 is turned on while the inching switch 42c is turned on, the wire electrode 12 having a predetermined length is sent out by one on operation, and the wire electrode from the tip of the torch TH is sent. 12 protrusion amount is adjusted.

  The operation remote controller 42 is originally provided in the wire supply device 13 so that the operator can adjust the output current I and the output voltage V and perform an inching operation while actually watching the welded portion near the wire electrode 12. Specifically, the operation remote controller 42 includes a rotary operation type current and voltage volume switches 42a and 42b for adjusting the output current I and the output voltage V, and a push button type inching switch for performing an inching operation. 42c. Based on various operations of the operation remote controller 42, the adjustment of the output current I and the output voltage V and the inching operation can be easily performed in the vicinity of the welding portion without performing the operation on the power supply device 11 side. In particular, it is suitable when the power cable 14 requires a length of several tens [m], such as when the welding object M is a long object or a large structure.

  Then, using the torch switch 41 and the inching switch 42c of the operation remote controller 42, the operator performs a predetermined operation as shown in FIG. 5, and an operation signal control device corresponding to the predetermined operation. Based on the input to 31, the control device 31 switches to the measurement mode described above.

  First, the operator turns on the torch switch 41 five times within a predetermined time T (for example, several seconds) while the inching switch 42c of the operation remote controller 42 is turned on. Since this operation is the same operation as the inching operation of the wire electrode 12, the protrusion amount of the wire electrode 12 by five times by the five on operations of the torch switch 41 in the on state of the inching switch 42 c. Only protrude. When this operation is completed within a predetermined time T, the control device 31 of the power supply device 11 retracts the wire electrode 12 protruding in the previous inching operation more than the protruding amount to switch to the measurement mode, and the torch TH The wire electrode 12 is housed in the contact tip THa at the tip of the switch, and then the measurement mode is switched.

  Next, the worker brings the contact tip THa at the tip of the torch TH into contact with the welding object M, and pseudo-wires the wire electrode 12 (see FIG. 1). When the torch switch 41 is turned on in this short-circuited state, actual measurement is started using this as a trigger. The actual measurement is completed in about several seconds, and the obtained total inductance value L (function) and total resistance value R are held in a storage device in the control device 31 for calculation of the tip voltage Va. .

  At the end of actual measurement, the operator turns on the torch switch 41 five times. By performing this operation, inching is performed to project the wire electrode 12 accommodated in the contact tip THa at the tip of the torch TH by a predetermined amount, and the measurement mode ends.

  In measurement modes including actual measurement, if a measurement error such as a short circuit failure at the tip of the torch TH, a measurement time shortage, or a measurement value error such as when an abnormal measurement value is acquired, the operator is informed. Abnormality notification is made. This abnormality notification is performed on a display unit or the like provided in the power supply device 11, but in the operation by using the torch switch 41 or the operation remote control 42, the worker is in the vicinity of the torch TH and is from the power supply device 11. Since it is assumed that it is far away, it is necessary to notify in the vicinity. Therefore, in the case of the arc welding machine 10 that performs arc welding while discharging an inert gas (carbon dioxide gas, argon gas, mixed gas thereof, etc.) from the tip of the torch TH, the control device 31 of the power supply device 11 is a gas cylinder 45. By controlling the control valve 46 that controls the supply of the inert gas from the gas, the abnormality notification is performed in advance by the sound of the gas discharged from the tip of the torch TH.

Next, characteristic effects of the present embodiment will be described.
(1) The power supply device 11 (control device 31) measures a total resistance value R and a total inductance value L (function L (I) in this embodiment) up to the tip of the electrode 12 for calculating the tip voltage Va. A measurement mode is provided. When switching to the measurement mode, a prescribed operation combining the torch switch 41 and the inching switch 42c included in the torch TH and the operation remote controller 42 of the wire supply device 13 is performed, so that the operated switch In addition to the original corresponding operations of 41 and 42c, switching to the measurement mode is performed. In other words, by using the switches 41 and 42c that are originally provided in the torch TH and the operation remote controller 42 to perform different operations, these torches in the vicinity of the electrode 12 are not provided with a separate switch for performing measurement. Measurement can be easily performed while confirming the state of the tip portion of the electrode 12 at the time of measurement by the prescribed operation of the switches 41 and 42c of TH and the operation remote controller 42. In addition, this makes it possible to easily perform measurement even when the power supply apparatus 11 itself is installed such that the distance from the electrode 12 is greatly separated.

  (2) When switching to the measurement mode, an operation for performing an inching operation combining the torch switch 41 and the inching switch 42c is performed within a predetermined time T with the inching switch 42c turned on in the present embodiment. By setting the torch switch 41 five times, it is possible to easily switch to the measurement mode by an operation using both the switches 41 and 42c.

  (3) At the end of the measurement mode, the measurement mode is ended by operating the same torch switch 41 that was operated at the time of switching (starting) to the previous measurement mode. Operation can also be facilitated.

  (4) When switching to the measurement mode, the original corresponding operation based on the prescribed operation combining the torch switch 41 and the inching switch 42c, that is, the electrode 12 protruding in the inching operation is switched to the measurement mode by the prescribed operation. At the same time as switching, it is stored in the contact tip THa at the tip of the torch TH. Thereby, when the electrode 12 is short-circuited at the time of measurement, the contact tip THa at the tip of the torch TH is brought into contact with the counterpart member (the welding target M) to make the electrode 12 pseudo short-circuited separately. It can be performed easily without requiring any operation.

  (5) The electrode 12 accommodated in the contact tip THa at the tip of the torch TH at the time of switching to the measurement mode is protruded by a predetermined amount from the contact tip THa when the measurement mode ends. Thereby, the transfer to the welding work which makes the electrode 12 protrude can be performed easily.

  (6) When notifying the abnormality at the time of actual measurement in the measurement mode, the operator is informed using the sound of gas released from the tip of the torch TH. That is, in the welding machine 10 according to the present embodiment that performs welding using an inert gas, an operator who is in the vicinity of the electrode 12 that is farther away from the power supply device 11 can be provided without using a means for informing that effect. Notification can be performed easily and reliably.

In addition, you may change embodiment of this invention as follows.
In the above embodiment, the torch switch 41 is operated five times within the predetermined time T while the inching switch 42c is turned on as the specified operation when switching to the measurement mode. The prescribed operation is not limited to this, and may be changed as appropriate. Further, although the torch switch 41 is operated five times as the prescribed operation at the end of the measurement mode, it may be changed as appropriate.

  In the above embodiment, the measurement mode is switched to or terminated based on the prescribed operation using the torch switch 41 and the inching switch 42c. However, the measurement mode is different from those provided in the torch TH and the operation remote controller 42. It is also possible to carry out using this switch. For example, rotational operation type current and voltage volume switches 42a and 42b provided in the operation remote controller 42 may be used. In addition, when operation switches other than the torch switch 41, the inching switch 42c, and the volume switches 42a and 42b are provided in the torch TH and the operation remote controller 42, those switches may be used.

  In the above embodiment, the DC reactor 25 having the supersaturation characteristic is used. However, a general reactor having a linear characteristic in which the current value and the inductance value change constant may be used. Incidentally, if such a reactor is used, the inductance value can be obtained by measuring the current attenuation once (the function need not be obtained), and the tip voltage Va can be easily calculated.

  In the above embodiment, the gas emission sound emitted from the tip of the torch TH is used when notifying an abnormality during actual measurement in the measurement mode. However, sound generation means and light emission means other than the gas emission sound are provided. Each means may be used in the present invention. In this case, it is preferable to use those provided in the torch TH, the operation remote controller 42, the wire supply device 13 and the like in the vicinity of the electrode 12. Moreover, it is good also as an aspect which does not perform abnormality alert | report.

10 Arc welding machine (welding machine)
11 Welding power supply device 12 Wire electrode (electrode)
13 Wire supply device 22 Inverter circuit 23 Welding transformer 24 Rectifier circuit (DC conversion means)
25 DC reactor (DC conversion means)
31 Control device (control means, tip voltage calculation means, resistance value calculation means, inductance value calculation means, switching means, abnormality notification means)
33 Current sensor (detection means)
34 Voltage sensor (detection means)
41 Torch switch (operation switch)
42 Operation remote control 42c Inching switch (operation switch)
45 Gas cylinder (Abnormality notification means)
46 Control valve (abnormality notification means)
TH Torch THa Contact Tip M Welding Target I Output Current Ip1 Current Value Ip2 Current Value V Output Voltage Va Tip Voltage R Total Resistance Value L Total Inductance Value L (I) Function

Claims (7)

An inverter circuit for converting DC power into high-frequency AC power, a welding transformer for adjusting the voltage of the converted AC power, and DC conversion means for generating DC output power suitable for welding from the secondary AC power of the welding transformer; And generating an arc for welding with the welding object based on the supply of the generated output power to the electrode, and within the apparatus, from the rectifier circuit provided in the DC conversion means Control means for calculating the tip voltage of the electrode based on the output current and the output voltage detected by the detection means provided in the power supply line on the output side, and controlling the inverter circuit based on the calculated tip voltage A welding power supply device comprising:
The total resistance value on the path to the electrode tip is calculated based on the voltage value of the output voltage when the electrode is short-circuited and the output current generated by the operation of the inverter circuit is a predetermined current value. And a resistance value calculating means for performing a short circuit on the electrode, and on the path to the tip of the electrode based on a current attenuation amount when the output current generated by the operation of the inverter circuit is set to a predetermined current value. The total resistance on the path to the tip of the electrode with respect to the voltage value of the output voltage detected by the detection means, having a measurement mode for executing processing including an inductance value calculation means for calculating a total inductance value A tip voltage calculating means for calculating the tip voltage by correcting a voltage change applied to the value and the total inductance value;
Various operation switches provided in each of a torch for supporting and supplying power to the electrode, and an operation remote controller provided in a wire supply device for supplying the electrode according to wear during welding. A welding power source apparatus comprising switching means for switching the measurement mode to be executable separately from the original corresponding operation of the operated switch based on a prescribed operation using at least one switch . In the welding power supply device according to claim 1,
The torch is provided with a torch switch, the operation remote controller is provided with an inching switch, and the inching operation of the electrode is performed based on an ON operation in which the torch switch and the inching switch are combined.
The welding power supply apparatus according to claim 1, wherein the switching means switches to the measurement mode based on the prescribed operation in which the torch switch and the inching switch are combined. The welding power supply device according to claim 2,
The welding power supply apparatus according to claim 1, wherein when the measurement mode ends, the switching means ends the measurement based on a prescribed operation of at least one of the torch switch and the inching switch. The welding power supply device according to claim 2 or 3,
Wherein the distal end portion of the torch contact tip for supplying power to the electrode is provided,
In the measurement mode , instead of directly short-circuiting the electrode, the contact chip is in a short-circuit state,
The switching means is configured to switch the measurement mode based on the prescribed operation combining the torch switch and the inching switch, and to project the electrode protruding in an inching operation as an original corresponding operation by the operation of both switches. The welding power supply device is housed in the contact tip. In the welding power supply device according to claim 4,
The switching means causes the electrode to protrude from the contact tip by a predetermined amount upon completion of the measurement mode. In the welding power supply device according to any one of claims 1 to 5,
Control of the inert gas released from the tip of the torch during the welding,
The welding power supply apparatus characterized in that the gas emission sound is used as an abnormality notification means for notifying an abnormality during actual measurement in the measurement mode.   A welding machine comprising the welding power supply device according to any one of claims 1 to 6.

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