Helical Stator Core with Insulator Coupling for Outer Rotor Motor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional clothes washing machines with indirect-coupled BLDC motors experience energy loss and noise due to belt transmission, and the manufacturing of stator cores is complex and material-intensive, with issues of vibration and deformation at high speeds.
Innovation Solution
A stator with a helical core made from a single metal sheet, featuring recesses and insulators to reduce stress and weight, and a coupling mechanism to prevent layer separation, allowing for stable installation and reduced material usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a helical core is used to simplify manufacturing and reduce material loss, then manufacturing complexity and material loss are reduced, but the core cannot be bent if a protrusion is formed for coupling
Solution Approach 1:
The protrusion for coupling is extracted from the core structure and relocated to the insulator. The insulator now includes a protrusion that extends from its inner surface toward the center, which couples the stator to the tub. This allows the helical core to be manufactured without the complexity of forming protrusions while maintaining the coupling function through the insulator's protrusion.
Solution Approach 2:
The coupling function is moved from the radial dimension (protrusion on core) to the axial dimension (protrusion on insulator). The insulator's protrusion extends axially from the inner surface toward the center, providing coupling capability without requiring radial protrusions on the bent core.
2Strength
If a protrusion is formed in the core for coupling, then coupling strength is sufficient, but the core cannot be bent due to excessive width
Solution Approach 1:
The coupling protrusion is extracted from the core and transferred to the insulator. The insulator's protrusion provides the necessary coupling strength to resist fastening forces during high-speed rotation, while the core itself remains simple and bendable without protrusions.
3Device complexity
If an indirect-coupled motor with belt transmission is used, then motor structure is simpler, but energy loss and noise are generated
Solution Approach 1:
The motor rotor is directly coupled to the drum shaft, merging the motor assembly with the drum assembly. This eliminates the belt transmission intermediary, removing energy loss and noise generation while maintaining structural simplicity through direct integration.
4Loss of energy
If direct-coupled BLDC motor is used to eliminate energy loss and noise, then energy efficiency is improved, but stator weight and vibration at high speed cause coupling damage
Solution Approach 1:
The insulator is positioned between the helical core and the coupling protrusion to cushion and distribute the mechanical stresses. The insulator absorbs vibrations and shocks during high-speed rotation (600-2000 RPM), preventing stress concentration that would lead to coupling damage from stator weight and rotor trembling.
Solution Approach 2:
The stator assembly uses composite construction with the insulator material providing electrical insulation and mechanical cushioning properties. The combination of helical core (metal sheets), insulator (insulating material), and coupling protrusion creates a composite structure that handles both electromagnetic function and mechanical stress.
Data Source
AI summary
A stator of an outer rotor type motor is provided. The stator may include a helical core having stacked layers formed by winding a single metal sheet having a predetermined shape in a helical direction, a base and teeth that protrude from the base. The stator may also include an insulator made of electrical insulation material that surrounds the helical core, recesses formed in the base of the helical core that reduce stress due to the winding of the single metal sheet and disposed under the teeth, and auxiliary recesses formed in a bottom of the recesses.