C-Shaped Laser Beam Oscillation for Low-Dross Sheet Metal Cutting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional laser machining apparatuses for cutting stainless steel sheet metal suffer from poor surface roughness and excessive dross adhesion, resulting in low cut surface quality.
Innovation Solution
A laser machining apparatus and method that incorporates a machining head, a moving mechanism, and a beam vibrating mechanism to vibrate the laser beam in a C-shaped pattern, causing beam spots to overlap and improve the cutting process, thereby enhancing the quality of the cut surface.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If the laser beam is used in a defocused state to cut sheet metal with plate thickness of 3 mm or more, then the kerf width is widened to enable cutting, but the surface roughness of the cut surface deteriorates and dross adhesion increases
Solution Approach 1:
The patent applies mechanical vibration to the laser beam through a beam vibrating mechanism that vibrates the laser beam in both the parallel direction (X-axis) and orthogonal direction (Y-axis) to the cutting advancing direction. This vibration causes the beam spot to trace a C-shaped pattern on the workpiece surface, preventing dross adhesion and improving cut surface quality while maintaining adequate kerf width for cutting 3 mm or more thick sheet metal
Solution Approach 2:
The patent transforms the static focused laser beam into a dynamic vibrating beam. The beam spot position is dynamically controlled to move in a C-shaped vibration pattern, creating time-varying heat input distribution that prevents dross formation and improves surface quality while maintaining the defocused state needed for thick material cutting
2Device complexity
If a fiber laser oscillator or DDL oscillator is used instead of a CO2 laser oscillator, then the device size is reduced and cost is lowered, but the beam waist becomes small and the kerf width becomes narrow
Solution Approach 1:
The patent uses beam vibration to effectively widen the kerf width despite the inherently small beam waist of fiber lasers and DDL oscillators. The C-shaped vibration pattern causes the beam spot to sweep across a wider area, creating a broader kerf that compensates for the narrow beam width while maintaining the advantages of compact, low-cost laser sources
Solution Approach 2:
The patent addresses the narrow kerf width problem by introducing temporal and spatial vibration dimensions to the laser beam. Instead of relying solely on beam width, the C-shaped vibration pattern extends the effective cutting width through controlled beam spot displacement in both X and Y directions, effectively widening the kerf without changing the laser oscillator
3Manufacturing precision
If the laser beam is vibrated in a C-shaped pattern with beam spot overlap, then the cut surface quality is improved and dross adhesion is reduced, but the device complexity increases due to the beam vibrating mechanism
Solution Approach 1:
The patent employs a beam vibrating mechanism that vibrates the laser beam in two directions (parallel and orthogonal to cutting direction) to create a C-shaped vibration pattern. This controlled vibration improves cut surface quality and reduces dross adhesion by preventing molten material from adhering to the cut surface, while the mechanism remains integrated with the existing laser machining apparatus
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 C-shaped vibration pattern allows for improved cut surface quality by reducing dross adhesion and enhancing the kerf width, resulting in a more precise and cleaner cut on stainless steel sheet metal.
Implementation Method 1
a laser machining apparatus and a laser machining method that machine sheet metal made of stainless steel by a laser beam
Implementation Method 2
a fiber laser oscillator or a direct diode laser oscillator (DDL oscillator) that is compact and low cost has been more widely used
Implementation Method 3
a beam vibrating mechanism configured to vibrate the laser beam in both a parallel direction with a cutting advancing direction of the sheet metal and an orthogonal direction orthogonal to the cutting advancing direction
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A control device controls a beam vibrating mechanism to vibrate a laser beam in a C-shaped vibration pattern in which a beam spot is moved from a first irradiation position at a front end in a cutting advancing direction to a second irradiation position at a rear side in the cutting advancing direction and displaced in an orthogonal direction to the cutting advancing direction, and is moved from the second irradiation position to a third irradiation position at a front end in the cutting advancing direction and displaced in the orthogonal direction to the cutting advancing direction, and movement from the first irradiation position to the third irradiation position via the second irradiation position, and movement from the third irradiation position to the first irradiation position via the second irradiation position are repeated. The control device performs control to cut the sheet metal W by causing beam spots in the first to third irradiation positions to overlap one another.