Laser Welding Stator Conductors Asymmetric Bridge
Solution Overview
Problem
Conventional methods for manufacturing stators using laser beam welding face challenges in connecting rod-shaped conductors at large distances without damaging the laser source due to feedback effects, and existing methods are not robust enough to handle variations in component dimensions, leading to potential errors and damage to insulation and other components.
Innovation Solution
The method involves tilting the stator so that the conductor ends are inclined perpendicular to the laser beam, allowing the melt to form an asymmetrical or loop-shaped bridge between conductors, which can span gaps up to 2 mm, and adjusting the laser beam's intensity and movement to ensure the melt solidifies without damaging adjacent components, while maintaining sufficient electrical conductivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional laser beam welding is used to connect rod-shaped conductors, then welding automation and productivity are improved, but the method cannot handle large gaps between conductors and risks damaging the laser source due to feedback effects
Solution Approach 1:
The patent applies asymmetry by tilting the conductor arrangement relative to the laser beam direction. Instead of symmetric perpendicular arrangement, conductors are positioned at an angle (e.g., 45°) to the laser beam, creating an asymmetric welding configuration. This asymmetric setup allows the laser beam to bridge larger gaps between conductors while preventing feedback effects from damaging the laser source, as the angled arrangement directs reflected light away from the laser source.
Solution Approach 2:
The patent introduces a new dimension by tilting the entire conductor assembly relative to the laser beam direction. This dimensional change transforms the traditional perpendicular welding geometry into an angled configuration, enabling the laser beam to effectively bridge gaps of up to 2 mm between conductors while maintaining welding automation and preventing laser source damage through controlled light reflection geometry.
2Manufacturing precision
If conventional laser welding with perpendicular alignment is used, then welding precision is maintained, but the method is not robust enough to handle variations in component dimensions and positional tolerances
Solution Approach 1:
The patent applies preliminary action by pre-tilting the conductor ends at specific angles (e.g., 45°) before the welding process. This preliminary angular positioning creates a wedge-shaped gap configuration that guides the laser beam's energy distribution, allowing the process to automatically compensate for variations in component dimensions and positional tolerances during welding, thereby maintaining precision while increasing robustness.
Solution Approach 2:
The patent changes the geometric parameter of the welding configuration from perpendicular to angled (e.g., 45° tilt). This parameter change transforms the welding geometry to create a wedge-shaped interaction zone between the laser beam and conductors, which provides inherent tolerance compensation for dimensional variations, making the process more adaptable while maintaining welding precision.
3Length of stationary object
If laser beam intensity is increased to bridge larger gaps between conductors, then gap bridging capability is improved, but adjacent components and insulation may be damaged
Solution Approach 1:
The patent uses asymmetric angular positioning of conductors relative to the laser beam to control energy distribution. The angled configuration (e.g., 45° tilt) creates an asymmetric energy density distribution in the wedge-shaped gap, concentrating laser energy where needed to bridge gaps of up to 2 mm while naturally directing excess energy away from adjacent components and insulation, preventing damage without requiring excessive beam intensity.
Solution Approach 2:
By introducing the angular dimension to the welding configuration, the patent creates a three-dimensional energy distribution pattern instead of a two-dimensional perpendicular interaction. This dimensional change allows the laser beam to bridge larger gaps through extended energy path length while the angled geometry naturally limits energy spread to protected areas, preventing damage to insulation and adjacent components.
4Length of stationary object
If conductors are welded at large distances apart, then design flexibility is improved, but welding reliability decreases due to potential errors and defects
Solution Approach 1:
The patent applies preliminary action by pre-positioning conductors at specific angled orientations (e.g., 45° tilt) before welding. This preliminary angular arrangement creates a controlled wedge-shaped gap configuration that guides the laser beam's melting and bridging process, ensuring reliable weld formation even at large conductor separations of up to 2 mm by optimizing energy distribution along the gap.
Solution Approach 2:
The patent introduces angular positioning as an additional dimension to the welding configuration, transforming the gap-bridging problem from a one-dimensional distance challenge into a two-dimensional geometric solution. This dimensional change enables reliable welding at larger conductor distances by using the angular geometry to control and optimize laser energy distribution across the extended gap.
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 approach enables efficient, error-free welding of rod-shaped conductors over larger distances, reduces faulty joints, and protects insulation and other components from damage, allowing for automated and cost-effective manufacturing with improved robustness to positional variations.
Implementation Method 1
laser welding at least one first conductor and one second conductor from the plurality of conductors, so that a bridge is formed as an electrical connection between the first conductor and the second conductor
Implementation Method 2
the material of the first conductor, liquefied by a laser beam
Implementation Method 3
the molten metal, which follows gravity downwards, to run at an angle to the axial direction of the stator
Implementation Method 4
the laser beam is angled relative to the axial direction of the conductors or their ends
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
The invention relates to a stator (10) for an electric machine comprising a stator package (12); a stator winding, which comprises a plurality of rod-shaped conductors (16a, 16b), which are inserted through the stator package (12) in an axial direction (A); wherein at least one first conductor (16b) and an adjacent second conductor (16b) of the plurality of conductors are electrically connected to each other on an end face (20) of the stator package (12) by means of a bridge (34) formed by laser welding; wherein the bridge (34) formed by laser welding extends at an angle to the axial direction (A) between the conductor ends (18a, 18b) of the first conductor (16a) and the second conductor (16b).