Magnetically Loaded Composite Rotor Manufacturing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for manufacturing magnetically loaded composite (MLC) rotors face issues such as magnetic particle clumping, which causes imbalance and potential destruction of the rotor and stator assembly at high speeds, and the abrasive nature of powdered magnetic material that damages the mandrel and makes rotor removal difficult, leading to micro-cracks and reduced production efficiency.
Innovation Solution
A method involving a rotatable mandrel coated with a release agent and layered with fibre material to prevent magnetic particle penetration, using woven or non-woven fibre materials, and applying a magnetic field to align particles during the curing process, along with intermediate resin-impregnated layers to control particle distribution and enhance structural integrity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a release agent layer is applied to the mandrel to facilitate rotor removal, then ease of manufacture is improved, but the magnetic particles still scratch the mandrel and release agent, reducing reliability
Solution Approach 1:
The patent introduces a sacrificial intermediate layer comprising a first plurality of fibres arranged in a first direction, positioned between the magnetic particles and the mandrel. This intermediate layer acts as a mediator that prevents magnetic particles from scratching the mandrel and release agent during rotor removal, while still allowing easy separation. The intermediate layer is deliberately designed to be less strong than the outer rotor layers, making it the preferred failure plane during removal.
Solution Approach 2:
The sacrificial intermediate layer is applied to the mandrel before the magnetic particle-containing resin is wound onto the mandrel. This preliminary action ensures that the protective barrier is in place before the abrasive magnetic particles are introduced, preventing damage from the outset while maintaining ease of rotor removal.
2Manufacturing precision
If magnetic particles are allowed to flow freely during manufacturing, then manufacturing precision is improved, but particle clumping occurs causing imbalance and potential destruction at high speed
Solution Approach 1:
A non-magnetic intermediate layer is applied to the mandrel before introducing the magnetic particle-containing resin. This preliminary layer prevents magnetic particle clumping by providing a uniform surface that distributes particles evenly during the winding process, eliminating the need for post-manufacturing balancing while ensuring high-speed reliability.
Solution Approach 2:
The non-magnetic intermediate layer acts as a mediator between the mandrel and magnetic particles, preventing direct interaction that causes clumping. This intermediate layer ensures uniform particle distribution throughout the rotor structure, maintaining both manufacturing precision and operational reliability.
3Reliability
If the fibre material is made stronger to prevent particle penetration, then reliability is improved, but magnetic particles still penetrate through to the mandrel surface
Solution Approach 1:
The rotor structure is segmented into distinct layers: an outer functional layer containing magnetic particles, a middle sacrificial intermediate layer, and an inner mandrel interface layer. This segmentation allows each layer to perform its specific function - the outer layer contains particles reliably, while the intermediate layer prevents mandrel damage, achieving both reliability and manufacturing precision.
Solution Approach 2:
Different layers of the rotor are given different properties: the outer layers are made strong for particle containment, while the intermediate sacrificial layer is made deliberately weaker for easy removal. This local differentiation of material properties allows the strong outer layers to prevent particle penetration while the intermediate layer facilitates manufacturing.
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 allows for the successful formation of a magnetically loaded composite rotor with improved structural integrity, facilitating easy mandrel removal and reducing axial creep and micro-cracking, thereby enhancing the rotor's fatigue life and manufacturing efficiency.
Implementation Method 1
applying a magnetic field to align the magnetic particles in a required orientation whilst the resin is in the liquid state prior to gelling
Implementation Method 2
a magnetically loaded tow, including magnetic particles over said fibre material
Data Source
AI summary
A magnetically loaded composite rotor is formed by providing a mandrel 1 having a longitudinal axis 2. A release agent 3 is coated on the mandrel and a fiber material 4 of woven or non-woven material having fibers extending in the direction of the axis 2 is applied over the release agent. A thermoplastic resin impregnated tow 24 including magnetic particles 28 is wound over the fiber material 4, the fiber material substantially preventing the magnetic particles penetrating through to the mandrel.