JPH0323069A - Automatic welding equipment - Google Patents

Abstract

PURPOSE:To more satisfactorily perform welding at the adjustable speed of a torch by controlling a welding current according to the speed of the torch. CONSTITUTION:A mother board 4 is a main control part of an NC device for a welding machine and forms a memory card 5 wherein various data are stored and an adjustable speed pattern of the torch and transfers a programmable controller (PC)6 to control the torch and the data to control the whole of equipment. The PC6 is provided with a torch operating pattern forming means, a current pattern forming means and a torch operation control means and connected with a machine 9 and a welding power source 10 via a relay board 8. The PC6 outputs the adjustable speed pattern of the torch to the relay board 8 to control the welding current of the welding power source 10. In addition, the PC6 controls the machine 9 and also controls torch position control parts 11-13 according to the adjustable speed pattern of the torch.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to automatic welding equipment.

(Prior art) In conventional automatic welding equipment, welding a during welding is generally
The f flow is provided as shown in FIG.

First, an initial current is applied before the torch is accelerated, then a predetermined welding current is supplied when the torch is accelerated, and this welding current is supplied until the end of the torch deceleration, so that the torch is not decelerated. When Hiiragi is turned on, crater current is supplied for a certain period of time.

(Problem to be Solved by the Invention) However, in such an automatic welding device, the initial current, welding current, and crater current are only supplied in stages regardless of the acceleration/deceleration of the torch. (There was a problem that better welding could not be performed.)

The present invention has been made in view of these conventional problems, and an object of the present invention is to provide an automatic welding device that can perform good welding when accelerating and decelerating a torch.

"Structure of the Invention" (Means for Solving the Problems) In order to solve the above problems, the present invention provides an acceleration/deceleration movement pattern of the welding torch according to the welding specifications of the welded part, as shown in FIG. a torch operation pattern forming means FA for forming a current pattern similar to the acceleration/deceleration operation pattern of the welding torch formed by the means; Control the movement of the welding toe based on the formed movement pattern! lII1 torch operation tlJ Iil means 2;
1. 2nd stage 2 of 1st stage 2: The present invention is characterized by comprising a current stage 3 which performs current control based on the current pattern formed by the current pattern forming means FB.

Further, in the automatic welding apparatus 45, the current pattern is a pulse waveform, and the pulse waveform is formed in such a manner that a base current waveform and a maximum current waveform are alternately switched.

(Function) In the present invention, a current pattern is formed similar to a torch acceleration/deceleration operation pattern, and this current pattern is output in synchronization with the operation pattern.

Further, the current pattern is a pulse waveform, and this pulse waveform is formed by BPA that alternately switches between a base waveform and a waveform that determines the maximum N current.

<Example> Hereinafter, an example of the present invention will be described in detail with reference to the drawings. First, the overall configuration of the white motion welding apparatus of the present invention will be explained with reference to FIG.

In Figure 2, the motherboard 4 is an NCvtW for welding machine.
The main control unit is a memory card 5 that stores various data, and a programmable controller (hereinafter referred to as a PC) that forms the acceleration/deceleration pattern of the torch and controls the torch.
) 6 and sends and receives data to υlla the armor fluid.
I'll do it. Note that here, the device excluding the machine 9 and the welding power source 10 is referred to as the NC device for a welding machine. The motherboard 4 is connected to a CRT (display unit) 7, and also controls display contents. The PC6 performs the torch operation υI explained in FIG.
I [l means 1, welding M flow control means 2, welding flow control means 3
Machine 9, welding power source 10 via relay board 8 with
is connected to. Therefore, the PC 6 is configured to control the welding current of the welding power source 10 by outputting the aforementioned torch acceleration/deceleration pattern to the relay board 8. Further, the PC 6 controls the machine 9 and also controls the torch position control units 11 to 13 according to the acceleration/deceleration pattern of the torch.

Each torch position υItal1 part 11-13 is controlled by a servo motor 17 via a corresponding nervo amplifier 14-16.
~1 and encoders 20-22. The torch position η control unit 11 moves the torch in the X-axis direction of the coordinate axes.
IJI [IL, torch position I control section 12 is in the Y-axis direction, torch position control I2l1 section 13 is 7. Control v1 in the axial direction.

Therefore, in the torch, each servo amplifier 14-16 is driven under the control of each torch position control section 11-13, and this drive drives servo motors 17-19 that drive the torch in each axial direction. In addition, each servo motor 17~
The X.19 revolutions of the torch are detected by encoders 20 to 22 corresponding to each one, and by outputting this detected amount to each torch position control section, the X. This configuration controls movement in each of the Y and Z axis directions. The motor 19 includes a tachogenerator (TG) 23 for speed detection and a brake 24.
is connected to the relay board 8, and further connected to the relay board 8 are an MDI panel 25, a hand box 26, and a welding detection section 27 for detecting welding of a welded portion.

Next, the specific structure of the PC 6 mentioned above will be explained with reference to FIG.

P C 6 Ha, mainly the central processing unit! (CPU) 28,
It also includes a ROM 30 and a RAM 31 connected to the CPU 2 8 via a system bus 29. R.O.
M30 stores the operating program of the PC6,
The RAM 31 also stores various data, and the CPU
28 is υIl by these programs and various data.
It is composed of 1 line for 1 work. Further, the PC 6 includes communication control units 32 to 34 on the moving axes X, Y, and Z of the torch, and outputs movement commands in each axis direction of the torch. Furthermore, the PC 6 has an interface (1/F) 35 for transmitting and receiving data with the motherboard 4, a timer 36 used for counting time as described later, and a digital input/output interface.
It is equipped with 37 outputs (DIO).

Next, signals sent and received between the PC 6 and the relay board 8 will be explained with reference to FIG.

First, the activation signal is an activation command C output from the PCB to the relay board 8. The welding current detection signal is a current detection signal output from the welding current m10 to the relay board 8 when a welding current is detected. That is, when the welding power source 10 receives a start signal, it applies a high frequency voltage between the torch tip and the material (workpiece) to generate an arc, but at this time, when a current flows between the torch and the material, Welding electricity! 1
0 outputs a welding current detection signal to the relay board 8.

The pulse current command 1p and the base current command ib are current patterns formed by the current control means 2 of the relay board 8, and are signals that support the welding current. In the case of the wooden tip, each of these two types of current patterns has a trapezoidal waveform, and is switched at a predetermined period as described later. Further, the torch speed command is an acceleration/deceleration pattern that commands the acceleration/deceleration of the torch, and is formed by the toe Y-operation control stage 1 of the PC 6, and is formed by the welding current control means 2 of the relay board 8.
, is output to the synchronization means 3. Note that the DC/AC switching signal is a signal that switches between supplying the welding current in an alternating current manner as described later and supplying the welding current in a direct current manner as in the conventional case.

Next, the operation of the present invention will be explained.

First, when performing welding, the PC 6 outputs the above-mentioned activation signal to the relay board 8, and then outputs the acceleration/deceleration pattern of the torch. Relay board 8 receives the
A pulse current command II) of a current pattern with a different maximum value according to the acceleration/deceleration pattern, and a base It flow command I
form b. Here, in this example, the waveform of each current command is
As shown in FIG. 5(a), the signals have different trapezoidal waveforms at the highest point. Next, the relay board 8 operates as shown in FIG. 5 (
As shown in b), the operation of the welding power source 10 is tll@ so as to form a current waveform in which two types of trapezoidal waveform currents having different maximum values are alternately switched.

Hereinafter, specific formation of the welding current will be explained. FIG. 6 shows an example of welding current. When the welding power source 10 detects a welding current as shown in Figure 7, after the period of brie-flow TG1 in which inactive bamboo gas such as argon gas is preliminarily applied /lk if 4, the welding current detection signal is changed to N.
This is output to the G device side, but upon receiving this, the PC 6 issues a command to flow the initial II current IS. The initial II current IS is supplied for an initial current time TS, and as this TS elapses, the relay board 8 sends a pulse current command If) and a base current command Ib to increase the welding current step by step at a constant rate. Form.

First, welding current tA in relay board 8
For t[l, 1,000 stages 2, the torch acceleration/deceleration slope α and target speed lax are determined by the torch acceleration/deceleration pattern described above, and the acceleration time Ta is determined from the following equation.

Ta=Vmax/α The acceleration time Ta obtained here is the upslope time TO
shall be.

Next, as shown in FIG. 7, the relay board 8 obtains the number of interruptions during acceleration n@ by dividing Ta by the interruption period Δt. Note that the interrupt period Δt is obtained by the timer 36 mentioned above.

Furthermore, regarding the pulse current command Ip and base current command Ib, by dividing the respective differences between the target pulse N flow IP and base current IB and the initial current Is by the number of interruptions n,
Addition per interrupt period Δ[1ΔIp. Find Δlb. That is, the addition signals ΔIp and Δlb for each interrupt period are obtained by the following equations.

ΔIp = (IP-13)/n Δlb = (113-18)/n The welding current is formed based on the additions ΔIp and Δlb obtained in this way, the cutting period Δt, and the number of cuttings n. Ru. That is, ΔIp and Δib are added alternately and sequentially to each pulse current command ip and base current command 1b at every interrupt period Δt. As a result, as shown in FIG. 6, the peak value of the pulse current can be increased in sequence by synchronizing the welding current with the acceleration time of the torch.

When the upslope operation of the welding Ti flow is completed, the pulse current IP and the base current IB are alternately supplied, and are supplied in an alternating current manner in the same way as the melting Ffi current during the acceleration time. The time Tp of the pulse current IP at this time and the base current 113
The time 18 can be arbitrarily set, and in the example of FIG. 6, it is about 2 + t< of the above-mentioned interrupt period Δ[, but it may be the same time as Δ[.

When this constant speed period ends, the relay board 8 calculates the deceleration start timing from the remaining torch movement am and the torch speed at that time. When this deceleration start timing is recognized, the relay board 8 executes down slope current calculation in the same manner as described above.

First, find the deceleration time opposite to the above, and set this down
1- Obtain the number of interrupts n from the interrupt period To and the interrupt period Δ[.

Next, the current subtraction amounts Δ■p and Δlb for the interrupt period Δl are determined by the following equations.

Δlb = (IC-IP)/n Δlb = (IC-IB)/n However, IC is a crater current.

The welding current is shaped by the subtraction losses ΔIp and Δlb, the interruption period Δ° C., and the number of interruptions n thus obtained.

That is, until the welding current reaches the crater current i, the pulse current commands I
p, fA is calculated sequentially from base current command lb. As a result, as shown in FIG. 6, the welding current can be adjusted to match the deceleration time of the torch, and the peak value of the pulse current can be gradually reduced.

When the downslope time To ends, the crater current I
C during the crater current time Tc (It).

When this crater current time Tc ends, the pulse current command 1p and base current command 1b are cleared, and the start signal is turned off. Thereafter, the welding work is completed after continuing to release an inert gas such as argon gas during the afterflow TG2 period.

As described above, in this embodiment, two different types of trapezoidal currents with a maximum of one shift are alternately switched as the welding if flow, and the current value is sequentially increased 61 in accordance with the acceleration of the torch. In addition, the current value is gradually reduced as the torch decelerates.

Therefore, the welding current is adjusted according to the torch speed.
Therefore, welding 1B can be performed better than the conventional method of supplying a welding current regardless of the acceleration or deceleration of the torch.

The present invention is not limited to the above-mentioned embodiments, but can be implemented in other appropriate forms by making appropriate design changes.

[Effects of the Invention] As explained above, according to the present invention, the welding current is changed according to the speed of the torch.
There is an effect that welding can be performed better at toilJ speed.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an overview of the present invention, and FIG. 2 is a block diagram showing the overall configuration of an automatic welding apparatus according to the present invention. Fig. 3 is a block diagram showing the internal configuration of the programmable controller, Fig. 4 is a time chart of signals sent and received between the PC and the relay board, and Fig. 5 (a) 1 shows the pulse current command and base current command. FIG. 5(b) is an explanatory diagram showing an example of the welding current controlled by the command shown in FIG. 5(a), FIG. 6 is a current waveform diagram showing a specific example of the welding current, and FIG. FIG. 8 is an explanatory diagram schematically showing the calculation operation of the laser board, and FIG. 8 is a time chart showing the relationship between the welding current and the stove speed of the conventional device. 1A...Torch operation pattern forming means 1B...Current pattern forming means 2...Torch operation control means 3...Current control means

Claims (2)

[Claims] (1) A torch operation pattern forming means for forming an acceleration/deceleration movement pattern of the welding torch in accordance with the welding specifications of the welded part, and forming a current pattern similar to the acceleration/deceleration movement pattern of the welding torch formed by the means. a current pattern forming means for controlling the welding torch based on the operation pattern formed by the torch operation pattern forming means; a torch operation control means for controlling the operation of the welding torch based on the operation pattern formed by the torch operation pattern forming means; An automatic welding device characterized by comprising current control means for controlling current based on a formed current pattern. (2) The automatic welding apparatus according to claim 1, wherein the current pattern is a pulse waveform, and the pulse waveform is formed in such a manner that a base current waveform and a maximum current waveform are alternately switched. Welding equipment.