Induction Welding Inductor Layout for Uniform Composite Heating
Solution Overview
Problem
Existing induction welding systems for fiber reinforced thermoplastic composites face challenges in achieving uniform temperature distribution without hotspots or coldspots, require high current levels, and are inefficient, often necessitating bulky equipment that is not suitable for robotic applications.
Innovation Solution
An inductor unit with a coil unit and soft magnetic element configuration that concentrates current density and power density at the weld interface, allowing for precise temperature control and reduced cooling needs, adaptable to complex geometries, and capable of applying consolidation pressure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If high current levels (300-1000 A) are used to provide sufficient heating power, then the heating capability is improved, but the energy losses increase and system efficiency decreases
Solution Approach 1:
The patent changes the operating parameters by using moderate current levels (10-100 A) instead of high current levels, compensating through increased frequency (20-100 kHz) and optimized inductor design to achieve the required heating power with lower losses
Solution Approach 2:
The patent employs dynamic control of the heating process by adjusting frequency and power levels during welding, allowing precise temperature control at the weld interface while minimizing overall energy consumption and losses in the system
2Power
If high current levels are used to achieve sufficient heating, then the heating effectiveness is improved, but the equipment becomes bulky and heavy requiring transformer and resonance capacitors close by
Solution Approach 1:
The patent transitions from power-frequency operation to high-frequency operation (20-100 kHz), which allows the use of much smaller and lighter inductor components while achieving the same heating effectiveness, eliminating the need for bulky transformers and resonance capacitors
Solution Approach 2:
The patent replaces the traditional mechanical/electrical transformer-based power delivery system with a high-frequency electronic switching system, resulting in significant reduction of equipment size and weight while maintaining heating effectiveness
3Manufacturing precision
If uniform temperature distribution is achieved without hotspots or coldspots, then the weld quality is improved, but the control complexity increases
Solution Approach 1:
The patent applies local quality by concentrating the electromagnetic energy specifically at the weld interface through optimized inductor geometry and positioning, ensuring uniform heating only where needed while leaving other areas unaffected, thereby simplifying overall temperature control
Solution Approach 2:
The patent uses partial action by targeting only the specific region requiring welding with focused electromagnetic energy, avoiding excessive heating of surrounding areas, which simplifies temperature management and improves weld quality
4Reliability
If the inductor unit is designed to apply consolidation pressure on the weld seam area, then the welding effectiveness is improved, but the structural complexity increases
Solution Approach 1:
The patent merges the heating function and consolidation pressure application into a single integrated inductor unit, where the inductor structure itself serves both electromagnetic induction and mechanical pressing functions, thereby reducing overall system complexity
Solution Approach 2:
The inductor unit is designed with multi-functionality, serving simultaneously as the electromagnetic heating source and the mechanical pressure applying device, eliminating the need for separate components and simplifying the overall welding system
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 inductor unit achieves efficient, focused heating with reduced power consumption, enabling shorter cycle times and improved weld quality by minimizing heat-affected zones and allowing for flexible, robotic-friendly design.
Implementation Method 1
The at least one coil unit is configured to induce currents in the electrically conductive element
Implementation Method 2
the induced current is directed from the generative side to the active side of the electrically conductive element and concentrated therein
Data Source
AI summary
An inductor unit for controlled induction welding of at least one fiber reinforced thermoplastic composite workpiece, comprising at least one coil unit, at least one electrically conductive element and at least one soft magnetic element. The electrically conductive element has a generative side and an active side. The active side is configured to face the at least one workpiece to be welded and has a smaller cross-sectional surface area than the generative side. The at least one coil unit is configured to induce currents in the electrically conductive element, and the at least one soft magnetic element is arranged at least partly on the at least one electrically conductive element such that the induced current is directed from the generative side to the active side of the electrically conductive element and concentrated therein.