JP4554912B2 - Arc welding machine - Google Patents

Description

  The present invention relates to an arc welding machine in which a set value of welding conditions is switched by opening and closing a torch switch.

  FIG. 7 is an electrical connection diagram of a conventional arc welder. In FIG. 7, a welding power source main circuit INV rectifies commercial AC power, converts it into a voltage suitable for arc machining, and supplies it to the welding torch 1 and the workpiece 3. The welding wire 2 is fed to the workpiece 3 through the welding torch 1 by a feeding roll 4 directly connected to the wire feeding motor M.

  The torch switch TS outputs a torch signal Ts, the welding voltage setting circuit WV sets a welding voltage setting signal Wv having a predetermined value, and the welding current setting circuit WI sets a welding current setting signal Wi having a predetermined value. The crater voltage setting circuit CV sets a crater voltage setting signal Cv having a predetermined value, and the crater current setting circuit CI sets a crater current setting signal Ci having a predetermined value. The crater presence / absence selection circuit CS outputs a crater presence / absence selection signal Cs with a high level when it is selected, and the initial current presence / absence selection circuit SS has an initial current when it is selected with an initial current. The / none selection signal Ss is set to High level and output.

  The main control circuit SC starts to operate in response to the torch signal Ts from the torch switch TS, and when the crater presence / absence setting signal Cs is at the high level and the crater is present, the welding voltage setting signal Wv and the crater voltage setting signal Cv. The main control signal Sc is controlled according to the value of and a welding voltage is output. Further, the wire feed control signal Mc is output according to the values of the welding current setting signal Wi and the crater current setting signal Ci to control the wire feed speed.

  In the arc welding machine of the prior art described above, in the welding in which the welding location is a mixture of downward welding and vertical welding, welding is performed by changing the welding conditions corresponding to the welding location. Therefore, Japanese Patent Laid-Open No. 2000-218367 discloses a technique for switching welding conditions and the like using an open / close signal of a torch switch.

JP 2000-218367 A

  Depending on the weld location of the work piece, there are cases where downward welds and vertical welds may coexist, and the work conditions have been changed depending on the weld location. It was bad. Therefore, in order to improve workability, conventionally, a welding method is used in which welding conditions are used for the downward welding points, and crater conditions are used for the vertical welding points. However, welding was possible only in limited crater conditions at vertical welding locations.

In order to solve the above-described problems, the first invention includes a welding power source main circuit that rectifies a commercial AC power source, converts the commercial AC power source into a voltage suitable for arc machining, and supplies the load to the load, and the presence / absence of a crater filler in the welding mode. A welding mode setting circuit for setting, a welding voltage setting circuit for setting a predetermined welding voltage, a welding current setting circuit for setting a predetermined welding current, and a main for controlling the output in accordance with each of the set welding conditions. An arc welding machine comprising a control circuit,
A second welding voltage setting circuit for setting a predetermined second welding voltage; a second welding current setting circuit for setting a predetermined second welding current; and an ON period from the start of turning on the torch switch. The welding voltage setting value and the welding current setting value are selected when the time is equal to or longer than a predetermined torch monitoring time, and the second welding voltage setting value and the second welding current setting value are selected when the time is less than the torch monitoring time. A torch monitoring time discriminating circuit is provided, and when performing welding in which a downward welded portion and a vertical welded portion are mixed on the workpiece, the crater filler of the welding mode is set at the downward welded portion and the torch switch is set. The ON period is set to be longer than the torch monitoring time, the welding voltage setting value and the welding current setting value are selected and the downward welding is performed, and the welding mode is set to have the crater filler in the welding mode. An arc welding machine characterized in that vertical welding is performed by setting the ON period of the torch switch to be less than the torch monitoring time and selecting the second welding voltage setting value and the second welding current setting value. .

According to a second aspect of the present invention, there is provided a welding power source main circuit that rectifies a commercial AC power source, converts the voltage into a voltage suitable for arc machining, and supplies the voltage to a load, a welding mode setting circuit that sets presence / absence of a crater filler in the welding mode, An initial voltage setting circuit for setting a predetermined initial voltage, an initial current setting circuit for setting a predetermined initial current, a welding voltage setting circuit for setting a predetermined welding voltage, and a welding for setting a predetermined welding current A current setting circuit; a crater voltage setting circuit for setting a predetermined crater voltage; a crater current setting circuit for setting a predetermined crater current setting value; and a main control for controlling an output in accordance with each of the set welding conditions. An arc welding machine comprising a circuit,
A second initial voltage setting circuit for setting a predetermined second initial voltage, a second initial current setting circuit for setting a predetermined second initial current, and a predetermined second welding voltage are set. A second welding voltage setting circuit, a second welding current setting circuit for setting a predetermined second welding current, a second crater voltage setting circuit for setting a predetermined second crater voltage, A second crater current setting circuit for setting a predetermined second crater current; and the initial voltage setting value, the initial current setting value, when an on period from the start of turning on the torch switch is equal to or longer than a predetermined torch monitoring time; A welding voltage setting value, a welding current setting value, a crater voltage setting value and a crater current setting value are selected, and when the torch monitoring time is less than the second initial voltage setting value, the second initial current setting value, the first Welding voltage of 2 A torch monitoring time discriminating circuit for selecting a constant value, the second welding current set value, the second crater voltage set value, and the second crater current set value, and when performing welding and countercurrent welded portions are mixed, the downward welding at the location to set the no crater filler of the welding mode the oN period of the torch switch over the torch monitoring time the welding voltage setting value and the welding current Select a set value to perform downward welding, and set the welding mode with crater filler at the vertical welding location, set the on-period of the torch switch to be less than the torch monitoring time, and set the second initial voltage setting value, The second initial current setting value, the second welding voltage setting value, the second welding current setting value, the second crater voltage setting value, and the second crater current setting value. -Option to perform vertical welding and it is an arc welder according to claim.

  A third aspect of the invention is the arc welder according to claim 1 or 2, wherein the torch monitoring time is 0.5 [second] or more and 2 [second] or less.

  According to the arc welding machine of the present invention, in a welding in which a downward welded part and a vertical welded part are mixed in the work piece, a welding condition corresponding to the welded part can be selected before starting welding by opening and closing the torch switch. Workability can be greatly improved.

  FIG. 1 is an electrical connection diagram of the arc welder of the present invention. The same reference numerals as those in the electrical connection diagram shown in FIG.

  The torch switch TS outputs a torch signal Ts, the welding voltage setting circuit WV sets a predetermined welding voltage setting signal Wv, and the second welding voltage setting circuit WV2 sets a predetermined value of the twenty-first welding voltage. The setting signal Wv2 is set, the welding current setting circuit WI sets a predetermined value of the welding current setting signal Wi, and the second welding current setting circuit WI2 sets the predetermined value of the second welding current setting signal Wi2. The crater voltage setting circuit CV sets a crater voltage setting signal Cv having a predetermined value, and the second crater voltage setting circuit CV2 sets a second crater voltage setting signal Cv2 having a predetermined value. The current setting circuit CI sets a crater current setting signal Ci having a predetermined value, and the second crater current setting circuit CI2 sets a second crater current setting signal Ci2 having a predetermined value. That. The crater presence / absence selection circuit (welding mode selection circuit) CS for selecting the welding mode outputs the crater presence / absence selection signal Cs with a high level when selecting crater presence, and the initial current presence / absence selection circuit SS If selection is made that the initial current is present, the initial current present / absent selection signal Ss is set to the High level and output. Since the initial current setting circuit has the same configuration as described above, the illustration thereof is omitted.

  The welding voltage switching switch SW1 is connected to the a side when the torch monitoring determination signal Ca shown below is at the low level, and selects the welding voltage setting signal Wv. When the torch monitoring determination signal Ca is at the high level, b And the second welding voltage setting signal Wv2 is selected and output as the welding voltage setting signal Wv. The welding current switching switch SW2 is connected to the a side when the torch monitoring determination signal Ca is at the low level and selects the welding current setting signal Wi. When the torch monitoring determination signal Ca is at the high level, the b side To select the second welding current setting signal Wi2 and output it as the welding current setting signal Wi.

  The crater voltage switching switch SW3 is connected to the a side to select the crater voltage setting signal Cv when the torch monitoring determination signal Ca is at the low level, and is connected to the b side when the torch monitoring determination signal Ca is at the high level. Then, the second crater voltage setting signal Cv2 is selected and output as the crater voltage setting signal Cv. The crater current switching switch SW4 is connected to the a side when the torch monitoring determination signal Ca is at the low level and selects the crater current setting signal Ci. When the torch monitoring determination signal Ca is at the high level, the b side To select the second crater current setting signal Ci2 and output it as the crater current setting signal Ci.

  The main control circuit SC starts to operate in response to the torch signal Ts from the torch switch TS. When the crater presence / absence setting signal Cs is low level and no crater is present, the main control circuit SC performs main operation according to the value of the welding voltage setting signal Wv. The control signal Sc is controlled, and the wire feed control signal Mc is output according to the value of the welding current setting signal Wi to control the wire feed speed. When the crater presence / absence setting signal Cs is at a high level and a crater is present, the main control signal Sc is controlled according to values of an initial voltage setting signal, a welding voltage setting signal Wv, and a crater voltage setting signal Cv (not shown), The wire feed speed is controlled by outputting a wire feed control signal Mc according to the values of the initial current setting signal (not shown), the welding current setting signal Wi and the crater current setting signal Ci. Further, an arc period signal Wt is output during the arc generation period.

  The torch monitoring time setting circuit TM operates when a torch monitoring determination signal Ca shown below is at a low level, and outputs a torch monitoring time setting signal Tm for a predetermined period when the torch signal Ts from the torch switch TS is turned on. To do. The main control circuit SC continues to operate even when the torch signal Ts is turned off while the torch monitoring time setting signal Tm is input.

  The OR circuit OR takes the OR logic of the arc period signal Wt, the torch signal Ts, and the torch monitoring time setting signal Tm and outputs it as the OR signal Or.

  The torch monitoring time discriminating circuit CA operates during a period in which the OR signal Or is at a high level, compares the ON period of the torch signal Ts at the start of welding with the torch monitoring time setting signal Tm, and turns on the torch signal Ts. If it is determined that the period is less than the torch monitoring time setting signal Tm, and the determination is made and then the torch signal Ts is turned on again within the period of the torch monitoring time setting signal Tm, the torch monitoring determination signal Ca becomes a high level and is output. . When the ON period of the torch signal Ts is equal to or longer than the torch monitoring time setting signal Tm, the torch monitoring determination signal Ca is output at a low level.

“Embodiment 1”
(Without crater filler)
FIG. 2 is a waveform diagram for explaining the operation of switching the setting values of the welding conditions in accordance with the opening / closing operation of the torch switch at the start of welding without the crater filler (normal welding) of the arc welder of the present invention shown in FIG. . 2A shows the time change of the torch signal Ts of the torch switch TS, FIG. 2B shows the time change of the torch monitoring time setting signal Tm, and FIG. 2C shows the time change of the arc period signal Wt. 2 (D) shows the time change of the OR signal Or, FIG. 2 (E) shows the time change of the torch monitoring determination signal Ca, and FIG. 2 (F) shows the time change of the welding voltage setting signal Wv. 2 (G) shows the time change of the welding current setting signal Wi, FIG. 2 (H) shows the time change of the output voltage Iv, and FIG. 2 (I) shows the time change of the wire feed speed Ms. .

  When the torch signal Ts is turned on by turning on the torch switch TS at time t = t1 shown in FIG. 2A, the torch monitoring time setting circuit TM changes to the state shown in FIG. 2B according to the turning on of the torch signal Ts. A torch monitoring time setting signal Tm for a predetermined period T1 is output.

  The main control circuit SC starts its operation in response to turning on the torch signal Ts, controls the main control signal Sc in accordance with the value of the welding voltage setting signal Wv, and outputs the welding voltage Iv shown in FIG. . Further, the wire feed control signal Mc is controlled according to the value of the welding current setting signal Wi to output the wire feed speed Ms shown in FIG.

  The OR circuit OR takes the OR logic of the torch signal Ts, the arc period signal Wt, and the torch monitoring time setting signal Tm, and outputs the Or signal shown in FIG. The torch monitoring time discriminating circuit CA performs the monitoring operation of the torch signal Ts during the period when the Or signal is at the high level, and the on period T2 of the torch signal Ts and the torch monitoring time setting signal Tm shown in FIG. The torch signal Ts is determined to be less than the monitoring time T1, and the torch signal Ts is determined within the period of the torch monitoring time setting signal Tm after the determination. When the power is turned on again, the torch monitoring determination signal Ca shown in FIG. 2 (E) is set to a high level and output at time t = t2.

  When the torch monitoring determination signal Ca becomes High level at time t = t2, the welding voltage switching switch SW1 connects the contact to the b side, and switches the welding voltage setting signal Wv to the second welding voltage setting signal Wv2 and outputs it. To do. Further, the main control circuit SC controls the main control signal Sc according to the switched value of the second welding voltage setting signal Wv2, and outputs the welding voltage Iv shown in FIG. The welding current switching switch SW2 is also connected to the b side when the torch monitoring determination signal Ca becomes High level, and is switched from the welding current setting signal Wi to the second welding current setting signal Wi2, and the main control circuit SC In accordance with the value of the second welding current setting signal Wi2, the wire feed control signal Mc is controlled to output the wire feed speed Ms shown in FIG.

  At time t = t5 shown in FIG. 2A, when the torch switch Ts is turned from on to off and the torch signal Ts is set to the low level, the welding is finished, and the welding voltage Iv and the wire feed speed Ms are gradually reduced. Stop.

“Embodiment 2”
(With crater filler and no initial current)
FIG. 3 is a waveform diagram for explaining the operation of switching the setting values of the welding conditions in accordance with the opening / closing operation of the torch switch with and without the initial crater filler of the arc welder of the present invention shown in FIG. 3A shows the time change of the torch signal Ts of the torch switch TS, FIG. 3B shows the time change of the torch monitoring time setting signal Tm, and FIG. 3C shows the time change of the arc period signal Wt. 3D shows the time change of the OR signal Or, FIG. 3E shows the time change of the torch monitoring determination signal Ca, and FIG. 3F shows the time change of the welding voltage setting signal Wv. 3 (G) shows the time change of the crater voltage setting signal Cv, FIG. 3 (H) shows the time change of the welding current setting signal Wi, and FIG. 3 (I) shows the time change of the crater current setting signal Ci. 3 (J) shows the time change of the output voltage Iv, and FIG. 3 (K) shows the time change of the wire feed speed Ms.

  When the torch signal Ts is turned on by turning on the torch switch TS at time t = t1 shown in FIG. 3A, the torch monitoring time setting circuit TM responds to the turning on of the torch signal Ts according to FIG. 3B. A torch monitoring time setting signal Tm for a predetermined period T1 is output.

  The main control circuit SC starts operation in response to the torch signal Ts being turned on, controls the main control signal Sc in accordance with the value of the welding voltage setting signal Wv, and outputs the welding voltage Iv shown in FIG. . Further, the wire feed control signal Mc is controlled according to the value of the welding current setting signal Wi, and the wire feed speed Ms shown in FIG.

  The torch monitoring time discriminating circuit CA compares the on period T2 of the torch signal Ts at the start of welding with the monitoring time T1 of the torch monitoring time setting signal Tm, and the value of the on period T2 of the torch signal Ts is the monitoring time. When the torch signal Ts is turned on again within the period of the torch monitoring time setting signal Tm after determining that it is less than T1, the torch monitoring determining signal Ca shown in FIG. 3 (E) is set to the high level at time t = t2. And output.

  When the torch monitoring determination signal Ca becomes High level at time t = t2, the welding voltage switching switch SW1 connects the contact to the b side, and switches the welding voltage setting signal Wv to the second welding voltage setting signal Wv2 and outputs it. Then, the main control circuit SC controls the main control signal Sc according to the switched value of the second welding voltage setting signal Wv2, and outputs the welding voltage Iv shown in FIG. The welding current switching switch SW2 is also connected to the b side when the torch monitoring determination signal Ca becomes High level, and is switched from the welding current setting signal Wi to the second welding current setting signal Wi2, and the main control circuit SC According to the value of the second welding current setting signal Wi2, the wire feed control signal Mc is controlled to output the wire feed speed Ms shown in FIG. Subsequently, in the initial current period from time t2 to t3, when there is no initial current, the main control signal Sc is controlled according to the value of the second welding voltage setting signal Wv2, and the second welding current setting signal Wi2 is set. The wire feed control signal Mc is controlled according to the value of.

  At time t = t3 shown in FIG. 3A, when the torch switch TS is turned from on to off and the torch signal Ts changes from high level to low level, the main control circuit SC is switched from the initial current period to the welding current period. During the welding period, T4 controls the main control signal Sc according to the value of the second welding voltage setting signal Wv2, and outputs the welding voltage Iv shown in FIG. Further, the wire feed control signal Mc is controlled according to the value of the second welding current setting signal Wi2, and the wire feed speed Ms shown in FIG.

  At time t = t4 shown in FIG. 3A, when the torch switch Ts is turned from OFF to ON and the torch signal changes from Low level to High level, the main control circuit SC switches from the welding current period to the crater current period. In the crater period, T5 controls the main control signal Sc according to the value of the selected second crater voltage setting signal Cv2, and outputs the welding voltage Iv shown in FIG. Further, the wire feed control signal Mc is controlled according to the value of the second crater current setting signal Ci2, and the wire feed speed Ms shown in FIG.

  At time t = t5, when the torch switch Ts is turned from on to off and the torch signal Ts is changed from the high level to the low level, the welding is finished, the welding voltage Iv in FIG. 3 (J), and the ear feeding shown in FIG. 3 (K). The feeding speed Ms decreases slowly and stops.

  FIG. 4 is a waveform diagram for explaining the operation when the arc welding machine of the present invention shown in FIG. 1 has a crater filler and does not change the setting value of the welding conditions without opening and closing the torch switch for starting welding without the initial stage. is there. Also, detailed description of the same operation as that of the waveform diagram shown in FIG.

  When the torch signal Ts is turned on by turning on the torch switch TS at time t = t1 shown in FIG. 4A, the torch monitoring time setting circuit TM changes to FIG. 4B according to the turning on of the torch signal Ts. A torch monitoring time setting signal Tm for a predetermined period T1 is output.

  The main control circuit SC starts operating in response to the torch signal Ts being turned on, controls the main control signal Sc in accordance with the value of the welding voltage setting signal Wv, and outputs the welding voltage Iv shown in FIG. The wire feed control signal Mc is controlled in accordance with the value of the welding current setting signal Wi, and the wire feed speed Ms shown in FIG.

  The torch monitoring time discriminating circuit CA compares the ON high level period of the torch signal Ts shown in FIG. 4A with the monitoring time T1 of the torch monitoring time setting signal Tm, and the ON value of the torch signal Ts is determined. When the monitoring time T1 or longer, the torch monitoring determination signal CaLow level shown in FIG. 4E is maintained.

  At time t = t2, when the torch monitoring determination signal Ca is at the low level, the welding voltage switching switch SW1 connects the contact to the a side, selects and outputs the welding voltage setting signal Wv, and the main control circuit SC The main control signal Sc is controlled according to the value of the welding voltage setting signal Wv, and the welding voltage Iv shown in FIG. Also, the welding current switching switch SW2 is connected to the a side when the torch monitoring determination signal Ca is maintained at the low level, and the welding current setting signal Wi is selected and output. The main control circuit SC receives the welding current setting signal Wi. Depending on the value, the wire feed control signal Mc is controlled to output the wire feed speed Ms shown in FIG. Subsequently, during the initial current period from time t2 to t3, when there is no initial current, the main control signal Sc is controlled according to the value of the welding voltage setting signal Wv, and the wire is controlled according to the value of the welding current setting signal Wi. The feeding control signal Mc is controlled.

  At time t = t3 shown in FIG. 4A, when the torch switch TS is turned from on to off and the torch signal Ts changes from high level to low level, the main control circuit SC is switched from the initial current period to the welding current period. During the welding period, T3 controls the main control signal Sc according to the value of the welding voltage setting signal Wv to output the welding voltage Iv shown in FIG. 4 (J), and according to the value of the welding current setting signal Wi. The wire feed control signal Mc is controlled to output a wire feed speed Ms shown in FIG.

  At time t = t4 shown in FIG. 4 (A), when the torch switch Ts is turned on from off and the torch signal changes from low level to high level, the main control circuit SC determines that the welding current is switched to the crater current period. During the crater period, T5 controls the main control signal Sc according to the value of the selected crater voltage setting signal Cv to output the welding voltage Iv shown in FIG. 4 (J), and according to the value of the crater current setting signal Ci. The wire feed control signal Mc is controlled to output a wire feed speed Ms shown in FIG.

“Embodiment 3”
(With crater filler and initial current)
FIG. 5 is a waveform diagram for explaining the operation of switching the set values of the welding conditions in accordance with the opening / closing operation of the torch switch at the start of welding with and without the crater filler of the arc welder of the present invention shown in FIG. Further, detailed description of the same operation as that of the waveform diagram shown in FIG. 2 is omitted, and only differences are described.

  When the torch signal Ts is turned on by turning on the torch switch TS at time t = t1 shown in FIG. 5A, the torch monitoring time setting circuit TM responds to the turning on of the torch signal Ts in FIG. 5B. A torch monitoring time setting signal Tm for a predetermined period T1 is output.

  The main control circuit SC starts operating in response to the torch signal Ts being turned on, controls the main control signal Sc in accordance with the value of the welding voltage setting signal Wv, and outputs the welding voltage Iv shown in FIG. Then, the wire feed control signal Mc is controlled according to the value of the welding current setting signal Wi to output the wire feed speed Ms shown in FIG.

  The torch monitoring time discriminating circuit CA compares the on period T2 of the torch signal Ts at the start of welding with the monitoring time T1 of the torch monitoring time setting signal Tm, and the value of the on period T2 of the torch signal Ts is monitored. When the torch signal Ts is turned on again within the period of the torch monitoring time setting signal Tm after determining that the time is less than the time T1, the torch monitoring determining signal Ca shown in FIG. 5E is set to High at time t = t2. Output as level.

  When the torch monitoring determination signal Ca becomes High level at time t = t2, the welding voltage switching switch SW1 connects the contact to the b side, and switches the welding voltage setting signal Wv to the second welding voltage setting signal Wv2 and outputs it. The crater voltage switching switch SW3 is also connected to the b side and switched from the crater voltage setting signal Cv to the second crater voltage setting signal Cv2. Further, when the torch monitoring discrimination signal Ca becomes High level, the welding current switching switch SW2 is connected to the b side, switched from the welding current setting signal Wi to the second welding current setting signal Wi2, and output, and the crater current switching switch SW4. When the torch monitoring determination signal Ca becomes High level, the connection is made to the b side, and the crater current setting signal Ci is switched to the second crater current setting signal Ci2 and output. Then, during the initial current period from time t2 to t3, when there is an initial current, the main control signal Sc is controlled according to the value of the second initial voltage setting signal Sv2 (not shown), and the second initial current setting (not shown) is set. The wire feed control signal Mc is controlled according to the value of the signal Si2.

  At time t = t3 shown in FIG. 5 (A), when the torch switch TS is turned from on to off and the torch signal Ts changes from high level to low level, the main control circuit SC switches from the initial current period to the welding current period. In the welding period T4, the main control signal Sc is controlled according to the value of the second welding voltage setting signal Wv2 to output the welding voltage Iv shown in FIG. The wire feed control signal Mc is controlled according to the value of Wi2 to control the wire feed speed Ms shown in FIG.

  When the torch switch Ts is turned from OFF to ON at time t = t4 shown in FIG. 5A and the torch signal changes from low level to high level, the main control circuit SC determines that the welding current period has switched to the crater current period. During the crater period, T5 controls the main control signal Sc according to the value of the selected second crater voltage setting signal Cv2 to output the welding voltage Iv shown in FIG. The wire feed control signal Mc is controlled according to the value of the setting signal Ci2 to control the wire feed speed Ms shown in FIG.

  FIG. 6 is a waveform diagram for explaining the operation when the arc welding machine of the present invention shown in FIG. 1 has a crater filler, the initial setting is present, and the welding conditions are not changed without opening and closing the torch switch at the start of welding. is there. Further, the same operation of the waveform diagram shown in FIG. 6 and the waveform diagram shown in FIG. 4 is omitted, and only the difference will be described.

  When the torch signal Ts is turned on by turning on the torch switch TS at time t = t1 shown in FIG. 6A, the torch monitoring time setting circuit TM changes to the state shown in FIG. 6B according to the turning on of the torch signal Ts. A torch monitoring time setting signal Tm for a predetermined period T1 is output.

  The main control circuit SC starts operation in response to the torch signal Ts being turned on, controls the main control signal Sc in accordance with the value of the welding voltage setting signal Wv, and outputs the welding voltage Iv shown in FIG. 6 (J). Then, the wire feed control signal Mc is controlled according to the value of the welding current setting signal Wi to output the wire feed speed Ms shown in FIG.

  The torch monitoring time discriminating circuit CA compares the ON high level period of the torch signal Ts shown in FIG. 6A with the monitoring time T1 of the torch monitoring time setting signal Tm, and the ON value of the torch signal Ts is determined. When the time is equal to or longer than the monitoring time T1, the low level of the torch monitoring determination signal Ca shown in FIG. 6E is maintained.

  When the torch monitoring determination signal Ca is maintained at the low level at time t = t2, the welding voltage switching switch SW1 connects the contact to the a side, selects and outputs the welding voltage setting signal Sv, and the crater voltage switching switch. SW3 also connects the contact to the a side, and selects and outputs the crater voltage setting signal Cv. Further, when the torch monitoring determination signal Ca becomes low level, the welding current switching switch SW2 is connected to the a side, and selects and outputs the welding current setting signal Wi. The crater current switching switch SW4 also has the torch monitoring determination signal Ca set to Low. When the level is reached, the crater current setting signal Ci is selected and output by connecting to the a side. Subsequently, in the initial current period from time t2 to t3, when the initial current is present, the main control signal Sc is controlled according to the value of the initial voltage / voltage setting signal Sv (not shown), and the value of the initial current setting signal Si (not shown) is determined. In response to this, the wire feed control signal Mc is controlled.

  At time t = t3 shown in FIG. 6A, when the torch switch TS is turned from on to off and the torch signal Ts changes from high level to low level, the main control circuit SC is switched from the initial current period to the welding current period. During the welding period, T4 controls the main control signal Sc according to the value of the welding voltage setting signal Wv to output the welding voltage Iv shown in FIG. 6 (J), and according to the value of the welding current setting signal Wi. The wire feed control signal Mc is controlled to output a wire feed speed Ms shown in FIG.

  When the torch switch Ts is turned on from off to on at time t = t4 shown in FIG. 6A and the torch signal changes from low level to high level, the main control circuit SC determines that the welding current period has switched to the crater current period. During the crater period, T5 controls the main control signal Sc according to the value of the selected crater voltage setting signal Cv to output the welding voltage Iv shown in FIG. 6 (J), and according to the value of the crater current setting signal Ci. The wire feed control signal Mc is controlled to output a wire feed speed Ms shown in FIG.

It is an electrical connection diagram of the arc welder of the present invention. FIG. 2 is a first waveform diagram illustrating an operation of the arc welder without a crater shown in FIG. 1. It is a 1st waveform diagram explaining the operation | movement with a crater of an arc welder shown in FIG. It is a 1st waveform diagram explaining the operation | movement with a crater of an arc welder shown in FIG. It is a 1st waveform diagram explaining the operation | movement with a crater of an arc welder and an initial current shown in FIG. It is a 1st waveform diagram explaining the operation | movement with a crater of an arc welder and an initial current shown in FIG. It is an electrical connection figure of the arc welding machine of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Welding torch 2 Welding wire 3 Workpiece 4 Feed roll AC Commercial alternating current power supply CA Torch monitoring discriminating circuit CI Crater current setting circuit CI2 Second crater current setting circuit CV Crater voltage setting circuit CV2 Second crater voltage setting circuit CS Crater presence / absence setting circuit (welding mode setting circuit)
INV Welding power supply main circuit M Wire feed motor MC Wire feed control circuit OR OR circuit SC Main control circuit SS Initial current presence / absence setting circuit SW1 Welding voltage changeover switch SW2 Welding current changeover switch SW3 Crater voltage changeover switch SW4 Crater current switching switch TM Torch monitoring time setting circuit TS Torch switch WG Welding power supply WI Welding current setting circuit WI2 Second welding current setting circuit WV Welding voltage setting circuit WV2 Second welding voltage setting circuit Ca Torch monitoring determination signal Ci Crater Current setting signal Ci2 Second crater current setting signal Cv Crater voltage setting signal Cv2 Second crater voltage setting signal Cs With / without crater selection signal Iv Welding voltage Mc Wire feed control signal Ms Wire feed speed Or OR signal Tm Torch Monitoring Time setting signal Ts Torch signal Sc Main control signal Ss With / without initial current selection signal Wi Welding current setting signal Wi2 First welding current setting signal Wt Arc period signal Wv Welding voltage setting signal Wv2 Second welding voltage setting signal

Claims (3)

Welding power main circuit that rectifies commercial AC power, converts it into a voltage suitable for arc machining, and supplies it to the load, welding mode setting circuit that sets whether or not the crater filler is in the welding mode, and preset welding voltage In an arc welding machine comprising a welding voltage setting circuit, a welding current setting circuit that sets a predetermined welding current, and a main control circuit that controls output according to each of the set welding conditions,
A second welding voltage setting circuit for setting a predetermined second welding voltage; a second welding current setting circuit for setting a predetermined second welding current; and an ON period from the start of turning on the torch switch. The welding voltage setting value and the welding current setting value are selected when the time is equal to or longer than a predetermined torch monitoring time, and the second welding voltage setting value and the second welding current setting value are selected when the time is less than the torch monitoring time. A torch monitoring time discriminating circuit is provided, and when performing welding in which a downward welded portion and a vertical welded portion are mixed on the workpiece, the crater filler of the welding mode is set at the downward welded portion and the torch switch is set. The ON period is set to be longer than the torch monitoring time, the welding voltage setting value and the welding current setting value are selected and the downward welding is performed, and the welding mode is set to have the crater filler in the welding mode. Wherein the ON period of the torch switch below the torch monitoring time by selecting the second welding voltage setting value and the second welding current setting value performs vertical welding, arc welder, characterized in that. Welding power main circuit that rectifies commercial AC power, converts it into a voltage suitable for arc machining, and supplies it to the load, welding mode setting circuit that sets whether or not the crater filler is in the welding mode, and preset initial voltage An initial voltage setting circuit for setting, an initial current setting circuit for setting a predetermined initial current, a welding voltage setting circuit for setting a predetermined welding voltage, a welding current setting circuit for setting a predetermined welding current, A crater voltage setting circuit for setting a predetermined crater voltage; a crater current setting circuit for setting a predetermined crater current setting value; and a main control circuit for controlling an output in accordance with each of the set welding conditions. In arc welding machine
A second initial voltage setting circuit for setting a predetermined second initial voltage, a second initial current setting circuit for setting a predetermined second initial current, and a predetermined second welding voltage are set. A second welding voltage setting circuit, a second welding current setting circuit for setting a predetermined second welding current, a second crater voltage setting circuit for setting a predetermined second crater voltage, A second crater current setting circuit for setting a predetermined second crater current; and the initial voltage setting value, the initial current setting value, when an on period from the start of turning on the torch switch is equal to or longer than a predetermined torch monitoring time; A welding voltage setting value, a welding current setting value, a crater voltage setting value and a crater current setting value are selected, and when the torch monitoring time is less than the second initial voltage setting value, the second initial current setting value, the first Welding voltage of 2 A torch monitoring time discriminating circuit for selecting a constant value, the second welding current set value, the second crater voltage set value, and the second crater current set value, and when performing welding and countercurrent welded portions are mixed, the downward welding at the location to set the no crater filler of the welding mode the oN period of the torch switch over the torch monitoring time the welding voltage setting value and the welding current Select a set value to perform downward welding, and set the welding mode with crater filler at the vertical welding location, set the on-period of the torch switch to be less than the torch monitoring time, and set the second initial voltage setting value, The second initial current setting value, the second welding voltage setting value, the second welding current setting value, the second crater voltage setting value, and the second crater current setting value. -Option to perform vertical welding, the arc welder, characterized in that.   The arc welding machine according to claim 1 or 2, wherein the torch monitoring time is 0.5 [second] or more and 2 [second] or less.

Images