DEVICE FOR DIRECTING THE MOVEMENT OF WELDING ELECTRODE ALONG THE BUTT OF JOINING PARTS

• US 3,855,446 A
• Filed: 11/17/1972
• Issued: 12/17/1974
• Est. Priority Date: 11/17/1972
• Status: Expired due to Term

• Current Assignee: Anatoly Ivanovich Galitsky, Gretel Artashesovna Akopian, Jury Fedorovich Nekrasov, Jury Petrovich Golin, Larisa Akimovna Ivanenko, Leonid Georgievich Kolesnichenko, Valentina Georgievna Kotova, Valery Grigorievich Snezhko
• Original Assignee: Anatoly Ivanovich Galitsky, Gretel Artashesovna Akopian, Jury Fedorovich Nekrasov, Jury Petrovich Golin, Larisa Akimovna Ivanenko, Leonid Georgievich Kolesnichenko, Valentina Georgievna Kotova, Valery Grigorievich Snezhko
• Inventors: Kotova, Valentina Georgievna, Akopian, Gretel Artashesovna, Galitsky, Anatoly Ivanovich, Golin, Jury Petrovich, Snezhko, Valery Grigorievich, Kolesnichenko, Leonid Georgievich, Ivanenko, Larisa Akimovna, Nekrasov, Jury Fedorovich
• Primary Examiner(s): Truhe, J. V.
• Assistant Examiner(s): Peterson, G. R.
• Application Number:
  US05/307,533
• Time in Patent Office: 760 Days
• Field of Search: 219/125R,125PL,137,131WF 250/202
• US Class Current: 219/124.34
• CPC Class Codes: B23K 9/0956 using sensing means, e.g. optical
• CPC Class Codes: B23Q 35/128 Sensing by using optical means

Abstract

A device for correcting the position of a welding electrode relative to the joint of parts being welded and to keep in axial relationship the weld seam and the joint, while the seam width is adjusted at the same time. The device has two photoelectric sensors indicating the position of the joint and the seam, and follow-up and control units associated with the sensors. In the course of welding, as the joint moves relative to the electrode, a control signal is generated which aligns the welding electrode with the joint of the parts being welded. In case of industrial interferences, the resulting displacement of the seam axis relative to the joint is corrected by a seam control system. The device is capable of maintaining a constant width of the seam in the course of welding.

Claims

1. A device for directing the movement of a welding electrode along the joint of parts being welded, comprising:

a first photoelectric sensor indicating the position of said joint and located along the path of the welding process ahead of said welding electrode, the position of said first sensor corresponding to a predetermined position of the electrode;

a follow-up system for tracing the direction of movement of said welding electrode relative to said joint of said parts being welded, said system being connected to said sensor;

a converter in said follow-up system to convert the output signal of said photoelectric sensor into a train of rectangular pulses, the input of said converter being connected to the output of said photoelectric sensor;

a negative signal wave shaper in said follow-up system corresponding to the right-hand position of said photoelectric sensor relative to the axis of said joint of said parts being welded, when viewed in the direction of the welding process, the input of said shaper being connected to the output of said converter;

a positive signal wave shaper in said follow-up system, corresponding to the left-hand position of said photoelectric sensor relative to the axis of said joint of said parts being welded, when viewed in the direction of the welding process, the input of said shaper being connected to the output of said converter;

a synchronizer in said follow-up system and having an input connected to said output of said converter, the output of said synchronizer being connected, respectively, to the other inputs of said positive and negative signal shapers;

an adder in said follow-up system and having inputs connected to respective outputs of said positive and negative signal shapers;

an integrator in said follow-up system and having an input connected to the output of said adder;

a seoncd photoelectric sensor indicating the position of the weld seam and arranged behind said electrode when viewed in the direction of the welding process, said second photoelectric sensor being rigidly connected to said electrode;

a control system to control the movement of said welding electrode relative to the axis of said weld seam, said control system being connected to said second photoelectric sensor indicating the position of the weld seam;

auxiliary wave shapers in said control system to shape positive and negative signals corresponding to the right-hand and lefthand positions of said second photoelectric weld seam position sensor relative to the axis of the weld seam when viewed in the direction of the welding process, the inputs of said Auxiliary shapers being connected to the output of said second photoelectric weld seam position sensor;

an auxiliary adder in said control system and having inputs connected to respective outputs of said auxiliary shapers;

an auxiliary integrator in said control system and having an input connected to the output of said auxiliary adder;

a logic coincidence circuit in said control system and having a first input connected to the output of said auxiliary integrator and having a second input connected to the output of said integrator in said follow-up system;

actuating means in said follow-up system, for moving said welding electrode;

a control unit to control said actuating means and having an input connected to the output of said logic coincidence circuit, the output of said control unit being connected to the input of said actuating means.

2. A device as claimed in claim 1, including an inhibiting unit to inhibit the movement of the welding electrode relative to the axis of said joint, said unit comprising:

a flip-flop with input connected to the output of said negative signal shaper in said follow-up system for tracing the direction of movement of said welding electrode;

a logic OR circuit having one input connected to the output of said flip-flop, and having a second input connected to the output of said negative signal shaper in said follow-up system for tracing the direction of movement of the welding electrode, said OR circuit having a third input connected to the output of said positive signal shaper in said follow-up system;

an inhibiting flip-flop having one input connected to the output of said logic OR circuit, and having another input connected to the output of said synchronizer in the same follow-up system;

a control key with input connected to the output of said inhibiting flip-flop, the output of said control key being connected to the input of said adder in said follow-up system tracing the direction of movement of said welding electrode along the joint of the parts being welded, the output of said control key being also connected to the input of said auxiliary adder in said control system for controlling the movement of the welding electrode relative to the axis of said seam.

3. A device as claimed in claim 1, including a welding current control system comprising:

a measuring unit for measuring the width of the joint of said parts being welded, the input of said measuring unit being connected to the output of said first photoelectric joint position sensor;

a welding current correction unit with input connected to the output of said unit for measuring the width of the joint;

a welding current controller with input connected to the output of said welding current correction unit, the output signal of said welding current controller correcting the welding current of said welding electrode.

4. A device as claimed in claim 2, including a control system to control the feed speed of filler wire, comprising:

a weld seam width measuring unit with input connected to said second photoelectric weld seam position sensor;

a correction unit to correct the feed speed of said filler wire, the input of said correction unit being connected to the output of said weld seam width measuring unit;

a filler wire feed speed controller with input connected to the output of said correction unit to correct the feed speed of the filler wire, the output signal of said filler wire feed speed controller correcting the feed speed of said welding electrode.

5. A device as claimed in claim 4, wherein the output of said control key of said inhibiting unit is connected to the input of said welding current correction unit and to the input of said correction unit of said control system to correct the feed speed of said filler wire.