Soft Bypass Access for Spatter-Free Welding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for controlling the output of welding devices in consumable electrode arc welding, such as short arc welding, struggle to completely prevent unwanted welding spatter due to high current and voltage change rates during the transition between short-circuit dissolution and arc re-ignition.

Innovation Solution

Implementing a method where opposite DC voltage is switched on in the current path based on specific default conditions related to welding process parameters like current, voltage, or resistance, synchronized with the clock frequency of the inverter power source, to actively reduce the welding power and facilitate a spatter-free material transfer by detecting both the initiation and end of the short-circuit state.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If high welding current is used during short-circuit phase, then material transfer efficiency is improved, but welding spatter formation increases

Engineering Contradiction:
Improvematerial transfer efficiencyVSAvoidwelding spatter
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent applies preliminary anti-action by detecting the approach of a weld droplet toward the workpiece (pre-short circuit state) and preemptively reducing the welding current before the short circuit actually occurs. This prevents the excessive current surge that would otherwise cause spatter, while still allowing efficient material transfer by maintaining appropriate current levels throughout the welding cycle.

Inventive Principle:
Principle #9Preliminary anti-action

Solution Approach 2:

The patent implements preliminary action by using sensor detection to identify the pre-short circuit state (when the droplet approaches the workpiece but has not yet contacted it) and taking corrective action by reducing current in advance. This allows the system to prepare for the upcoming short circuit event, ensuring smooth current transition and preventing spatter-causing current spikes.

Inventive Principle:
Principle #10Preliminary action

2Object-generated harmful factors

If welding current is rapidly reduced during short-circuit phase, then spatter formation is reduced, but material transfer consistency deteriorates

Engineering Contradiction:
Improvewelding spatterVSAvoidmaterial transfer consistency
Core Design Contradiction:
Object-generated harmful factorsVSManufacturing precision

Solution Approach 1:

The patent employs feedback control by continuously monitoring the welding process state through sensors that detect droplet position, current, and voltage. The control system uses this real-time feedback to dynamically adjust the welding current, reducing it smoothly during the short-circuit phase while maintaining overall material transfer consistency through closed-loop control that compensates for variations in the welding process.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent applies dynamics by making the welding current a dynamically adjusted parameter rather than a fixed value. The current is continuously modified based on the detected welding state (arc phase, approach phase, short-circuit phase, recovery phase), allowing optimal current levels for each stage of the welding cycle and ensuring both spatter reduction and consistent material transfer.

Inventive Principle:
Principle #15Dynamics

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach significantly reduces welding spatter by actively managing the current drop during both the onset and resolution of the short circuit, ensuring a smoother transition and minimizing spatter formation.

Implementation Method 1

one of the inverter voltages occurs in the at least one current path opposite DC voltage is switched on to support the steepness of the current drop

Methodology Applied
Scientific EffectElectrical voltage opposition: Electrical Resistance

Implementation Method 2

measured values representative of the instantaneous value of the welding process voltage are recorded synchronized with the clock frequency

Methodology Applied
Scientific EffectElectrical measurement: Ohm's Law

Implementation Method 3

Arc is ignited and the welding electrode is melted in the form of drops

Methodology Applied
Scientific EffectArc heating: Electric Arc

Implementation Method 4

the end of the electrode is melted in the form of drops

Methodology Applied
Scientific EffectJoule heating: Joule Heating

Implementation Method 5

the melted material is transferred to the workpiece

Methodology Applied
Scientific EffectGravity: Gravitation

Data Source

PatentEP1949997B1Soft bypass access
Publication Date: 2011.06.22 EWM HIGHTEC WELDING
  • EP1949997B1 patent drawingFigure 1
  • EP1949997B1 patent drawingFigure 2
  • EP1949997B1 patent drawingFigure 3

AI summary

Method for controlling the output of a welding device comprises carrying out a first allowance condition representing the start of an electrical short circuit as a result of drop transition into a second operating phase and a second allowance condition representing the end of an electrical short circuit in connection with the transition of this drop. An independent claim is also included for a welding device for electric arc welding.