JPS62296963A - Arc welding controlling method - Google Patents

Abstract

PURPOSE:To stabilize the weld quality by resetting a timer to the initial set time and forming a molten pool extending for the set time at the time of performing the arc cutting while the molten pool is formed. CONSTITUTION:A timer system circuit 5 or a different system from a welding controller 2 is provided and an arc cutting signal output circuit 13, the timer 14 and a power source 15 are connected in series respectively with a general purpose outside output terminal 2a of the controller 2. Furthermore, a switch 16 is connected with a general purpose outside input terminal 2b of the controller 2. When the arc cutting is performed while the molten pool is formed according to a storage program of the controller 2, the controller 2 is stopped abnormally and an arc cutting signal is supplied from the signal output circuit 13 to the timer 14 and the timer 14 is cleared and reset to the set time. Since the proper molten pool is formed at all times at the time of the arc cutting, the weld quantity is stabilized by this method.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention a. Field of Industrial Application The present invention relates to an arc welding control method, for example, TIG (TIG).
IG) It is suitable for application to a welding start method for obtaining stable welding during welding.

b. Prior Art TIG welding, which is a type of arc welding, is usually performed as follows. That is, at the start of welding, the tip of the electrode of the torch is brought close to the member to be welded (base material) to generate an arc, thereby forming a molten pool. After a molten pool is sufficiently formed, a welding rod is inserted, and the welding rod and torch are moved along a predetermined welding direction. As a result, the welding rod melts and adheres to the molten pool, and fuses with parts of the two workpieces to be welded to each other to form weld metal between them, and through this weld metal, the two The members to be welded are joined.

In this case, if welding is started before a sufficient molten pool is formed, the weld metal will not be formed well, and
Since this will result in welding defects, it is necessary to form a sufficient molten pool at the start of welding.

Furthermore, recently, automatic TIG welding equipment using robots has been widely adopted in the manufacture of automobile bodies and the like.

In TIG welding using conventional automatic TIG welding equipment, the fifth
As shown in the figure, the molten pool formation time T after arc generation is set by a timer built into the welding control device, and the torch movement operation is automatically performed after the set time elapses, that is, after the molten pool is formed. I have to.

C0 Problems to be Solved by the Invention However, in the conventional case, if arc breakage occurs for some reason during the molten pool formation period (when time TI has elapsed from the start of welding), the welding control device The automatic TIG welding equipment stops abnormally based on the arc breakage detection signal, and then generates an arc again to form a molten pool, but because it uses a timer built into the robot program. The molten pool forming time at this time is the remaining time Tz (Ti=TT+) of the timer, as shown in FIG. For this reason, the torch movement is started before a sufficient /8 molten pool is formed and the welding operation begins, resulting in a problem of poor welding.

The present invention has been made to solve the above-mentioned problems, and its purpose is to always form an appropriate molten pool and perform good arc welding in any case. The object of the present invention is to provide a method for controlling arc welding.

d. Means for Solving the Problems In order to solve the above-mentioned problems, the present invention sets the molten pool formation time using a timer, and moves the torch after the molten pool is formed to weld the workpiece. In the arc welding control method, when arc breakage occurs during the molten pool formation period, the timer is reset to a set time before the molten pool formation starts, and thereby the molten pool The re-formation can always be carried out over the set time.

Hereinafter, the first embodiment of the welding control method according to the present invention will be described.
This will be explained with reference to FIGS.

FIG. 1 schematically shows the configuration of an automatic TIG welding apparatus 1 that implements a welding control method according to the present invention.
A TIG welding machine and an operating arm (robot) that operate based on control signals output from the device 2, 5 a timer system circuit for setting the molten pool formation time, and 6 connected to the TIG welding machine 3 via a cable 7. The torches 8a and 8b are welded members (base metals) to be joined together, and 9 is a conducting wire for grounding these welded members 8a and 8b.

The above-mentioned TIG welding machine 3 is supplied with high frequency power through an electric wire 10a, and is also supplied with cooling water and shielding gas through vibrators 10b and 10c, respectively. On the other hand, a torch 6 is supported at the tip of the operating arm 4, and a reel 11 is attached to the middle part of the torch 6, and a welding wire 1 drawn out from this reel 11
2 is configured to be automatically drawn out in correspondence with the electrode 6a of the torch 6.

Further, in this embodiment, a timer system circuit 5 which is separate from the welding control device 2 is used, and both of these are connected to the second
They are connected to each other in the configuration shown in the figure. That is, a series circuit consisting of an arc breakage signal output circuit 13, a timer 14, and a TFI 15 is connected to the general-purpose external output terminal 2a of the welding control device 2. On the other hand, welding control device 2
A switch 16 is connected to the general-purpose external input terminal 2b, and this switch 16 is configured to be switched from an OFF state to an ON state when the timer 14 is set for the time T.

Next, a welding control method according to the present invention will be explained in relation to the operation of the automatic TIG welding apparatus 1 described above.

First, at the start of welding, a predetermined control signal is input from the device 2 to the drive mechanism (not shown) of the actuating arm 4 according to a program stored in advance in the welding control device 2, whereby the actuating arm 4 is actuated. electrode 6 of torch 6
The tip of a is placed near the joining location of the members to be welded 8a and 8b. Then, high-frequency power is supplied to the electrode 6a of the torch 6 and the electrode 6a is placed under an arc generating state, and the electrode 6a is operated by the operating arm 4 in a small circular motion at a predetermined location, thereby forming a molten pool. be done.

At this time, as shown in FIG. 3, an arc generation signal is supplied from the welding control device 2 to the timer 14 as a timer operation start signal in synchronization with the start of arc generation, that is, the start of molten pool formation. It becomes operational.

On the other hand, the welding '#iI <8 apparatus 2 enters a so-called "waiting for external input" state. Thereafter, when a predetermined time T preset in the timer 14 has elapsed, the switch 16 is turned on based on the time-up signal output from the timer 14, and the external input terminal 2b of the welding control device 2 is turned on. A predetermined command signal is input to this device 2.
The “wait for external input” state is released. Along with this,
Is there a weld on the operating arch 4? 11 A predetermined control signal (program signal) is supplied from the device 2 to operate the torch 6.
The electrode 6a starts moving in a predetermined welding direction (the direction indicated by the first arrow).

If arc generation failure occurs for some reason during the molten pool formation period, the welding control device 2 will enter an "abnormal stop" state based on a detection signal from a sensor not shown, and the arc will break. An arc break signal is supplied from the signal output circuit 13 to the timer 14. As shown in FIG. 4, if arc breakage occurs after time t (however, t<7') has elapsed from the start of welding, the timer 14 is cleared in response to the input of the arc breakage signal, and the timer 14 is cleared before the start of welding. It is completely reset at the set time T.

Thereafter, the automatic TIG welding device 1 is restarted from the beginning after a predetermined period of time based on a program stored in the welding control device 2 in advance.

At this time, the timer 14 is set to the original set time' as described above.
Since it is reset to r, the molten pool forming operation will be performed during the month from the time when welding is restarted to the set time T, and then the to-chiro electrode 6a will be moved for welding. . In TIG welding, the molten pool formation at the start of welding has a large effect on the quality of welding, but in this example, even if arc breakage occurs during the molten pool formation period, an appropriate molten pool is formed when welding is restarted. can always be formed and good welding can be obtained.

Note that the conditions necessary for forming a molten pool will differ depending on the materials and dimensions of the members 8a and 8b, but by changing the setting value of the current 1 m pressure supplied to the electrode 6a of the torch 6, the timer 15 It is possible to form an appropriate molten pool even if the set time T is constant.

In the above-described embodiment, the case of the automatic TIG welding apparatus 1 was described, but the present invention is also applicable to arc welding in general, including not only TIG welding but also MIG welding and the like.

e. Effects of the Invention As described above, in the present invention, when arc breakage occurs at the start of welding, the timer for setting the molten pool formation time is reset to the set time before the start of molten pool formation. Therefore, it becomes possible to re-form the molten pool after the arc breaks over the set time. Therefore, in any case, an appropriate molten pool is formed at the start of welding, and the torch is moved after an appropriate molten pool is formed, so that good and stable welding can always be performed.

[Brief explanation of the drawing]

FIGS. 1 to 4 show an embodiment of the present invention, in which FIG. 1 is a schematic diagram of an automatic TIG welding device used to carry out the method according to the present invention, and FIG. A circuit diagram showing the connection relationship between a welding control device and a timer, FIG. 3 is a time chart for explaining the welding operation of the welding device under normal conditions, and FIG. 4 is a circuit diagram showing the welding operation of the welding device when arc breakage occurs. 5 and 6 are time charts for explaining the operation, and are for explaining the conventional TIG (arc) welding control method, and FIG. 5 is a time chart similar to FIG. FIG. 6 is a time chart similar to FIG. 4. ■... Automatic TIG) displacement device, 2... Welding control device, 2a... General-purpose external output terminal, 2b... General-purpose external input terminal, 3... TIG welding machine, 4... Operation Arm (robot), 5... Timer system circuit, 6... Torch, 8a
, 8b... member to be welded, 12... welding wire,
13... Arc breakage signal output circuit, 14... Timer, 16... Switch. Fig. 3 When welding starts When time is up Fig. 4 When welding starts When time is up Fig. 5 When welding starts Fig. 6 When time is up Fig. 6 Welding Arc cut off Reseno When time starts when it occurs 1'j 7 o'clock procedure amendment departure ) July 29, 1985 Commissioner of the Patent Office Kuro 1) Aki Yu Tono 2 Ha], Indication of the case 1986 Patent Application No. 141587 2, Name of the invention Arc welding control method 3, Person making the amendment Related Patent applicant name (208) Suzuki Motor Co., Ltd. 4, agent 107 (and 2 others) Contents of amendment +11 Amended "high frequency power source" to "power source" in lines 6-7 of page 5 of the specification Masu. (2) On page 6, lines 15 to 17 of the specification, "As it is placed, -------- is formed." was amended to "When it is placed, a molten pool is formed." Masu. that's all

Claims (1)

[Claims] In an arc welding control method in which a timer is used to set a time for forming a molten pool, and a torch is moved after the molten pool is formed to perform arc welding on a workpiece, arc breakage occurs during the molten pool formation period. If this occurs, the timer is reset to a preset time before the start of molten pool formation, so that the molten pool can always be re-formed for the preset time. Method.