PM Rotor Magnetic Alignment Molding Without Discrete Magnets
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing manufacturing methods for permanent magnet (PM) motors face challenges such as the need for inventory control of discrete magnets, gluing magnets in the rotor, and a curing step, which are time-consuming and prone to human error.
Innovation Solution
A system and method for manufacturing PM motors that uses a mold with electromagnetic coils to align and inject a magnetic material into rotor cavities, eliminating the need for discrete magnets and adhesives, and allowing for automated and simultaneous magnet insertion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If discrete magnets are used in traditional PM motor manufacturing, then magnetic components can be individually controlled and assembled, but inventory control complexity increases and manufacturing time is extended due to sequential assembly steps
Solution Approach 1:
The patent merges the magnet assembly process with the rotor manufacturing process by injecting magnetic material directly into rotor cavities during injection molding. This combines what were previously separate operations (magnet fabrication, inventory management, and assembly) into a single integrated process, eliminating the need for discrete magnet handling and sequential assembly steps.
Solution Approach 2:
The patent performs preliminary action by pre-positioning magnetic material within rotor cavities during the injection molding process itself, before the rotor is completed. The electromagnetic coils are also pre-positioned in the mold, enabling automatic alignment and orientation of magnetic particles without requiring subsequent magnet assembly operations.
2Reliability
If discrete magnets are glued into the rotor, then magnets can be securely attached, but additional curing steps are required which extend manufacturing time
Solution Approach 1:
The patent replaces the mechanical/glue-based attachment system with an electromagnetic field-based system. Electromagnetic coils generate magnetic fields that orient and secure magnetic particles within the rotor cavities during injection molding, eliminating the need for adhesive materials and curing processes while ensuring reliable magnetic attachment through field-based control.
3Adaptability or versatility
If manual magnet insertion is used, then flexibility in handling different magnet types is maintained, but human error increases and automation is limited
Solution Approach 1:
The patent implements self-service through automated systems where electromagnetic coils automatically generate magnetic fields that orient and position magnetic particles according to predetermined patterns. The injection molding system automatically controls material injection, cooling, and ejection, eliminating manual intervention and associated human errors while maintaining flexibility through programmable control of different magnetic material types and configurations.
4Manufacturing precision
If traditional magnet assembly methods are used, then discrete magnets can be individually positioned, but the supply chain becomes more complex with inventory control requirements
Solution Approach 1:
The patent extracts magnets from the supply chain by transitioning from discrete magnet components to injectable magnetic material. This eliminates the need for separate magnet fabrication, inventory management, and quality control systems, simplifying the supply chain while maintaining positioning accuracy through direct injection and electromagnetic field control during the rotor manufacturing process.
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 reduces manufacturing time, eliminates human error, simplifies the supply chain, and allows for flexible material selection and full automation, resulting in a more efficient and cost-effective production process.
Implementation Method 1
The excited electromagnetic coils align the magnetic material into a desired magnetic orientation prior to solidification of the magnetic material
Implementation Method 2
A PM motor is a type of electric motor that uses permanent magnets to provide a magnetic field, which may interact with one or more windings to produce motion
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A system for manufacturing a rotor for a permanent magnet (PM) motor is provided. The system includes a mold configured to receive a rotor body including a plurality of rotor teeth and defining one or more rotor cavities and a plurality of electromagnetic coils including a plurality of magnetic cores, each of the plurality of magnetic cores configured to align with a respective one of the plurality of rotor teeth, and a plurality of electromagnetic windings. The system further includes a controller configured to, after the rotor body is positioned within the mold, close the mold, after closing the mold, excite the plurality of electromagnetic coils, inject a magnetic material into the one or more rotor cavities, wherein the excited electromagnetic coils align the magnetic material into a desired magnetic orientation prior to solidification of the magnetic material, de-energize the plurality of electromagnetic coils.