Pole Housing Laser Welding for Electric Motors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing pole housings for electric motors are complex, costly, and prone to geometric and constructive unevenness, with inadequate liquid and gas tightness, requiring multiple steps and post-processing.
Innovation Solution
A method involving pre-galvanized sheet metal formed into a cylindrical pole tube using laser welding to connect longitudinal edges, eliminating the need for additional welding and post-processing, with a cover attached via caulking or crimping to ensure fluid-tightness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If traditional tube manufacturing with stress-relief annealing and repeated drawing is used, then the pole housing can be produced, but the manufacturing process becomes complex with many individual steps and high costs
Solution Approach 1:
The manufacturing process is segmented into distinct operational stages: tube formation from sheet metal, laser welding of longitudinal edges, and subsequent machining operations. This segmentation allows each step to be optimized independently, reducing overall process complexity while maintaining precision requirements.
Solution Approach 2:
The tube is pre-formed from sheet metal with predetermined geometry and dimensions before welding and machining. This preliminary forming action establishes the basic structure, reducing the complexity of subsequent operations compared to forming the final geometry through multiple drawing steps.
2Ease of manufacture
If mechanical joining processes like crimping or flanging are used to connect interlocking elements, then the pole housing can be assembled, but geometric and structural irregularities occur with burrs requiring additional post-processing
Solution Approach 1:
The mechanical joining process is replaced with laser welding, which uses thermal energy to fuse materials without mechanical deformation. This substitution eliminates burr formation and geometric irregularities associated with crimping and flanging, achieving both ease of manufacture and high surface quality without post-processing.
3Ease of manufacture
If mechanical joining processes are used to connect tube edges, then the pole housing can be assembled, but sufficient protection against liquid ingress is not achieved
Solution Approach 1:
Mechanical joining is replaced with laser welding to create a continuous, seamless joint between tube edges. The welded joint provides complete liquid tightness by fusing the edges together, eliminating gaps and pathways for liquid ingress that exist in mechanical connections.
Solution Approach 2:
The connection method changes from mechanical (discrete contact points) to thermal (continuous fusion). This parameter change in the joining process transforms the joint characteristics from permeable to impermeable, achieving reliable liquid tightness while maintaining manufacturing simplicity.
4Reliability
If subsequent galvanizing process is applied after tube manufacturing, then corrosion protection is achieved, but the manufacturing time and costs increase
Solution Approach 1:
The sheet metal is pre-galvanized before tube formation and welding operations. This preliminary corrosion protection application eliminates the need for subsequent galvanizing, reducing manufacturing cycle time while maintaining reliable corrosion protection throughout the process.
Solution Approach 2:
Corrosion protection is applied beforehand to the sheet metal, creating a protective barrier before the tube undergoes forming and welding. This prior cushioning prevents corrosion during manufacturing operations and eliminates the need for post-manufacturing galvanizing, reducing overall production time.
5Manufacturing precision
If the tube is cut to length and end faces are ground, then the pole housing dimensions are precise, but the number of manufacturing steps increases
Solution Approach 1:
The tube length and end face geometry are predetermined during the initial sheet metal forming stage. This parameter setting in the forming process eliminates the need for separate cutting and grinding operations, maintaining precision through tooling while significantly increasing production speed.
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 method reduces production steps and costs, enhances manufacturing accuracy, and provides a high-quality, cost-effective, and impermeable pole housing suitable for large-scale production, particularly in the automotive industry.
Implementation Method 1
a pipe shell surface made of pre-galvanized sheet material is joined to form a pole tube by means of a material-bonded laser welding process
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
The invention relates to a method for producing a pole housing (16) for an electric motor, in which a tube shell surface (4) made of a, preferably galvanized, sheet metal material is prepared, in which the tube shell surface (4) made of the sheet metal material is formed into a cylindrical pole tube (2) such that the shell longitudinal edges (6), extending in the tube longitudinal direction (L), of the tube shell surface (4) face one another, and in which the shell longitudinal edges (6) of the tube shell surface (4) are connected together, forming a closed pole tube (2), wherein a provided cover (14) is fastened in a form- and/or force-fitting manner as end shield to an end-face tube end (12a) of the pole tube (2).