Laser Welding Clamping Control for Resin Burr and Crack Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing laser welding apparatuses face challenges in applying appropriate clamping force during laser welding of resin members, leading to issues like excessive burrs, cracks, and inadequate melting due to insufficient pressing, which are not effectively addressed by prior technologies that do not adjust clamping force in real-time with the changing state of the resin members during welding.
Innovation Solution
A laser welding apparatus that includes a clamping unit, a laser emitter, a displacement sensor, and a control unit to continuously monitor the displacement of the resin members' contact surfaces and adjust the clamping force accordingly, increasing or decreasing it in response to thermal expansion and softening of the laser beam-absorbing resin member, while also adjusting the laser output to match the state of the resin members.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If clamping force is increased to press resin members against each other, then contact pressure is improved, but excessive burrs and cracks may form due to residual stress
Solution Approach 1:
The clamping force is dynamically adjusted during laser welding based on real-time displacement measurements. The control unit increases clamping force when displacement indicates thermal expansion, and decreases it when displacement reversal indicates softening, preventing both insufficient pressing and excessive force throughout the welding process
Solution Approach 2:
A displacement sensor continuously monitors the displacement of contact surfaces during laser welding and feeds this information back to the control unit. The control unit uses this feedback to automatically adjust the clamping force, creating a closed-loop control system that adapts to the changing state of resin members
2Object-generated harmful factors
If clamping force is decreased to avoid excessive burrs and cracks, then harmful factors are reduced, but insufficient pressing causes fine gaps and inadequate heat transfer
Solution Approach 1:
The clamping force transitions from a static value to a dynamic parameter that adapts throughout the welding process. High clamping force is applied initially to ensure good contact, then adjusted downward as thermal expansion occurs, and further reduced when softening begins, maintaining optimal pressing force at each stage
Solution Approach 2:
The displacement sensor and control system detect thermal expansion and softening early in the welding process, allowing preemptive adjustment of clamping force before problematic conditions develop. This prevents both insufficient pressing and excessive force from occurring
3Manufacturing precision
If clamping force is adjusted in real-time, then welding quality is improved, but device complexity increases
Solution Approach 1:
The manual or static mechanical clamping system is replaced with an automated electromechanical system. The displacement sensor electronically detects contact surface displacement, and the control unit automatically adjusts the clamping force via an actuator, replacing what would otherwise require complex manual intervention or multiple mechanical adjustment mechanisms
Solution Approach 2:
The system uses the resin members' own thermal expansion and softening behaviors as control signals. The displacement sensor detects these natural phenomena, and the control unit automatically responds by adjusting clamping force, allowing the process to self-regulate based on the material's inherent properties without requiring external complex control algorithms
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 configuration ensures appropriate clamping force is applied to prevent burrs and cracks, facilitates heat transfer, and achieves better melting quality by dynamically adjusting forces and laser output based on the resin members' state during welding.
Implementation Method 1
The other one of the two resin members is formed of a laser beam-absorbing resin that absorbs laser beams
Implementation Method 2
The laser beam-absorbing resin member is thermally expanded when absorbing a laser beam during laser welding
Implementation Method 3
joins a first resin member... and a second resin member... by melting the first contact surface and the second contact surface with a laser beam
Implementation Method 4
the laser beam-absorbing resin member, which continues absorbing the laser beam without sufficiently transferring heat
Data Source
AI summary
A first resin member including a first contact surface and formed of laser beam-transmissive resin and a second resin member including a second contact surface, which contacts the first contact surface, and formed of laser beam-absorbing resin are arranged one upon the other. A laser welding apparatus includes a clamping unit abutting the second resin member and applying clamping force to the second resin member, a laser emitter emitting laser beam, a laser controller controlling output of the laser beam, a displacement sensor measuring displacement of the second contact surface in stacking direction of the resin members, and a control unit controlling the clamping unit to adjust the clamping force corresponding to displacement amount of the second contact surface continuously or intermittently obtained from the displacement sensor.