Laser-Welding Ranging Mechanism for Precise Focus Spot Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Laser welding of secondary battery cell tabs is prone to defects due to imprecise location of the laser focus spot, caused by variability in welding distance resulting from factors like tab bending, fixture imprecision, and robotic manipulator errors, with manual measurements leading to significant errors.
Innovation Solution
A ranging system for laser-welding tools that includes a ranging device and coupling mechanism to determine precise welding distances by moving into and out of the laser beam path, using ranging lasers and sensors to ensure accurate focus spot alignment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If manual measurements are used to determine welding distance, then the measurement process is simple and quick, but the measurement precision deteriorates with errors of 1 mm or more
Solution Approach 1:
The patent replaces manual mechanical measurement methods with an automated optical ranging device that uses light-based measurement techniques. The ranging device emits light signals and measures the time of flight or phase shift to calculate distance, substituting human-operated mechanical tools with an automated optical system that achieves sub-millimeter precision while maintaining operational simplicity through integration with the laser-welding tool.
2Measurement precision
If the ranging device remains in the beam path during welding, then the ranging measurements can be continuously taken, but the welding beam is blocked and welding cannot be performed
Solution Approach 1:
The patent implements a dynamic positioning system where the ranging device can rapidly move between two positions: in the beam path for ranging measurements and out of the beam path for welding operations. This dynamic repositioning allows the system to alternate between measurement and welding modes, enabling continuous operation without compromising either ranging capability or welding productivity. The coupling mechanism provides precise control over the ranging device's position relative to the laser beam path.
Solution Approach 2:
The system employs periodic action by alternating between ranging mode and welding mode in a cyclical manner. The ranging device moves into the beam path to take measurements, then moves out to allow welding, creating a periodic sequence of measurement-weld cycles. This periodic operation ensures that both ranging and welding functions are performed systematically without interference, maintaining both measurement precision and welding efficiency.
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
Enables highly accurate measurement of welding distances, reducing errors to within ±1 mm and ensuring high-quality welds by adjusting the laser focus spot before welding.
Implementation Method 1
a ranging device (124) designed and configured to determine a ranging distance to the welding location
Implementation Method 2
a coupling mechanism (128) designed and configured to couple the ranging device (124) in a fixed relationship relative to the laser-welding tool (108) such that: when the ranging device (124) is determining the ranging distance, at least a portion of the ranging device (124) is located in a ranging position in the beam path; and when the laser-welding tool (108) is emitting the welding beam so as to make the weld, the ranging device (124) is located in a welding position out of the beam path
Data Source
AI summary
Ranging systems for laser-welding tools that include laser-based ranging devices that are moved into and out of a corresponding beam envelop that contains one or more laser-welding beams for making welds. In some embodiments, a ranging system of this disclosure includes a coupling mechanism for coupling one or more ranging devices to a laser-welding tool, wherein the coupling mechanism alternatingly moves the ranging device(s) from a welding position to a ranging position or allows the ranging device(s) to be alternatingly moved between such positions. Ranging systems of this disclosure obtain accurate and precise ranging distances that contribute to precisely locating a focus spot of each laser-welding beam relative to each welding location so as to minimize the occurrence of mis-formed weld from improper focus spot locations. Laser-welding systems incorporating such ranging systems and related methods of forming welds are also disclosed.