Pivot Contact Mechanism for MIG Welding Torch Neck

Solution Overview

Problem

Conventional MIG welding torch neck connectors experience fatigue and require a human interface for changes, making them inefficient and prone to errors due to the need for screw-based clamping mechanisms.

Innovation Solution

A quick-change connector with a pivotally mounted contactor that uses resilient members to establish electrical contact and securely hold the neck in place, allowing for easy insertion and removal without the need for screws, ensuring reliable electrical connections and adaptable to various neck configurations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a screw-based clamping mechanism is used to connect the neck to the torch body, then the neck is securely held in place, but the components experience fatigue and require frequent maintenance, and human intervention is needed for changes

Engineering Contradiction:

Improveconnection reliabilityVSAvoidneck change ease

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The contactor automatically engages with the neck upon insertion and maintains electrical connection and mechanical retention without requiring human intervention for operation. The system serves itself by using the insertion motion to trigger engagement and maintain connection throughout the welding process.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent replaces the traditional screw-based mechanical fastening system with an electrical contactor that uses spring pressure and electrical contact to achieve both mechanical retention and electrical connection. This substitution eliminates the need for threaded fasteners and manual tightening operations.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Strength

If a screw-based clamping mechanism is used to connect the neck to the torch body, then the connection is secure, but the system requires human interface for changes which increases complexity and potential for errors

Engineering Contradiction:

Improveclamping strengthVSAvoidconnector complexity

Core Design Contradiction:

StrengthVSDevice complexity

Solution Approach 1:

The contactor merges the electrical connection function and the mechanical retention function into a single integrated component. The same contactor that provides electrical contact also provides the spring-based clamping force to hold the neck in place, eliminating the need for separate fastening mechanisms.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The contactor automatically engages with the neck upon insertion and maintains electrical connection and mechanical retention without requiring human intervention for operation. The system serves itself by using the insertion motion to trigger engagement and maintain connection throughout the welding process.

Inventive Principle:

Principle #25Self-service

3Reliability

If conventional screw connectors are used, then electrical connection is established, but the fatigue cycling of components reduces reliability over time

Engineering Contradiction:

Improveelectrical connection reliabilityVSAvoidcomponent service life

Core Design Contradiction:

ReliabilityVSDuration of action of stationary object

Solution Approach 1:

The patent replaces the traditional screw-based mechanical fastening system with an electrical contactor that uses spring pressure and electrical contact to achieve both mechanical retention and electrical connection. This substitution eliminates the need for threaded fasteners and manual tightening operations.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The contactor uses a spring-based dynamic retention mechanism that can accommodate thermal expansion and contraction, vibration, and minor misalignments. The spring pressure automatically adjusts to maintain reliable electrical contact and mechanical retention throughout the component's service life, unlike rigid screw fasteners that are subject to fatigue.

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

The solution enables efficient and reliable electrical connections capable of handling over 600 amperes, reduces fatigue, and simplifies the neck-changing process, enhancing the versatility of the welding torch for multiple applications.

Implementation Method 1

Each resilient member may be a helical spring

Methodology Applied

Scientific EffectHelical spring: Spring

Implementation Method 2

The resilient member having a higher spring force engages the head portion of the body member and the other resilient member engages the pivot portion of the body member

Methodology Applied

Scientific EffectElasticity: Elasticity

Data Source

PatentUS9669487B2Electrical contact for MIG welding torch

Publication Date: 2017.06.06 ILLINOIS TOOL WORKS INC

AI summary

A contactor providing for electrical contact in a welding torch includes a body member having first and second opposite sides, and adjacent pivot and head portions. The pivot portion has an outwardly curved contact surface on the second side providing a pivot point. The head portion also has a contact surface on the second side. The pivot portion has a shorter length between the first and second sides than the head portion. The contactor may be pivotally mounted in a torch connector body. At least one resilient member urges the contact surface of the pivot portion into engagement with an inner flange surface of the connector body, and biases the head portion into an opening in the torch connector body. The contact surface of the head portion is engageable with a torch neck inserted into the torch connector body, and provides an electrical connection between the torch body and neck.