Contact Element for Plasma Arc Torch Wear Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Contact start plasma arc torches face issues with component wear and misalignment, leading to reduced productivity and accuracy due to the need for frequent replacement of consumable parts, particularly the power contact, which is not designed to be easily replaceable and requires disassembly, and the stiffness of the power cable affecting the torch's maneuverability.

Innovation Solution

A component for contact start plasma arc torches featuring a hollow body with a channel for slidably receiving an electrode, a contact element with distinct surfaces for electrical communication and physical contact, and a resilient element to impart separation force, allowing for reduced wear on non-consumable components and improved alignment during operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the power contact is made movable to enable contact start operation, then the torch can initiate plasma arcs effectively, but the power contact and cable experience increased wear and reduced reliability

Engineering Contradiction:
Improvecontact start capabilityVSAvoidpower contact durability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The power contact system is segmented into a stationary power contact attached to the torch body and a movable contact element attached to the electrode. This segmentation allows the electrode to move for contact start operation while the stationary power contact remains fixed, eliminating wear on the power contact and improving reliability.

Inventive Principle:
Principle #1Segmentation

2Reliability

If the power contact is made stationary to improve reliability, then the power contact durability increases, but the electrode cannot be moved to initiate contact start plasma arcs

Engineering Contradiction:
Improvepower contact durabilityVSAvoidcontact start capability
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

A contact element is introduced as an intermediary between the stationary power contact and the movable electrode. The contact element is attached to the electrode and moves with it, while the stationary power contact remains fixed. This intermediary allows the electrode to move for contact start operation while the power contact remains stationary, resolving the contradiction between reliability and operability.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Productivity

If consumable components are made easily replaceable to reduce downtime, then productivity improves, but the torch assembly requires more complex disassembly and reassembly procedures

Engineering Contradiction:
Improvecomponent replacement speedVSAvoidassembly disassembly complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The electrode assembly is segmented into modular components (electrode, contact element, and optional resilient element) that can be assembled and disassembled as a unit. This modular segmentation allows rapid replacement of consumable components without requiring complex disassembly of the entire torch assembly, improving productivity while maintaining manageable complexity.

Inventive Principle:
Principle #1Segmentation

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 extends the lifetime of torch components, reduces wear on non-consumable parts, and enhances operational accuracy and productivity by maintaining alignment and reducing the need for frequent replacements, while allowing for easier maintenance and improved maneuverability.

Implementation Method 1

a resilient element to impart a separation force

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 2

a contact element... The first surface facilitates electrical communication with a power supply

Methodology Applied
Scientific EffectElectrical conduction: Conduction (electrical)

Implementation Method 3

The separation causes an arc to be formed between the electrode and the nozzle in the plasma chamber. The arc ionizes the introduced gas to produce a plasma jet

Methodology Applied
Scientific EffectArc ionization: Electric Arc

Data Source

PatentEP2801244B2Component for a contact start plasma arc torch
Publication Date: 2020.04.15 HYPERTHERM INC
  • EP2801244B2 patent drawingFigure 1
  • EP2801244B2 patent drawingFigure 2A~2C
  • EP2801244B2 patent drawingFigure 3A~3B

AI summary

A component for a contact start plasma arc torch is provided. The component includes a hollow body defining a channel with a longitudinal axis. The channel is capable of slideably receiving an electrode body along the longitudinal axis. The component includes a contact element disposed in the hollow body and includes a first surface and a second surface. The first surface is adapted to facilitate electrical communication with a power supply and the second surface is adapted to physically contact a surface of the electrode body when the plasma arc torch is operated in a transferred arc mode. In addition, the second surface is characterized by the absence of physical contact with the surface of the electrode body when the torch is operated in a pilot arc mode.