Rotor Assembly with Interlocking Shaft Structures
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The manufacturing of permanent magnet electric motors is complex and inefficient, with high tolerance requirements increasing costs and complexity, particularly in methods like thermal shrink-fitting.
Innovation Solution
A rotor assembly for permanent magnet electric motors featuring a shaft arrangement with interlocking shaft structures that compress a magnet member within a jacket member, providing radial compression and improved manufacturability, efficiency, and durability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If thermal shrink-fitting or traditional manufacturing methods are used, then the magnet member can be assembled into the rotor, but the manufacturing process becomes complex and labor-intensive with high tolerance requirements
Solution Approach 1:
The rotor assembly is divided into distinct modular components: a magnet member with integrated shaft structures, a jacket member, and bearing assemblies. Each component can be manufactured independently with standard tolerances and then assembled together, eliminating the need for complex thermal shrink-fitting processes and reducing overall manufacturing complexity
Solution Approach 2:
The shaft structures are integrated within the magnet member, which is then received within the jacket member, creating a nested configuration. The bearing assemblies are received within cavities of the jacket member. This nesting allows components to be assembled in a straightforward sequence without requiring high-precision fitting or thermal processes
2Reliability
If high tolerance requirements are imposed on parts, then assembly quality improves, but manufacturing cost and complexity increase
Solution Approach 1:
By segmenting the rotor into modular components with standardized interfaces, each part can be manufactured using conventional machining processes with standard tolerances. The modular design ensures proper fit and function through design features rather than relying on tight tolerances across all surfaces, thereby reducing manufacturing cost while maintaining assembly quality
Solution Approach 2:
The magnet member serves multiple functions: it provides the magnetic field structure, contains the shaft structures for rotational support, and interfaces with the jacket member for radial compression. This multi-functionality reduces the number of separate components needed and simplifies the overall manufacturing process while maintaining reliable assembly
3Strength
If traditional single-shaft configurations are used, then the structure is simple, but the ability to compress the magnet member radially and secure it within the rotor is insufficient
Solution Approach 1:
Instead of a single shaft, the design uses multiple shaft structures (first and second shaft structures) positioned at different locations within the magnet member. These segmented shaft elements work together to provide distributed radial compression and secure the magnet member more effectively than a single shaft could, while still maintaining a relatively simple overall structure
Solution Approach 2:
The shaft structures extend in multiple dimensions within the magnet member, with some shafts extending radially and others axially. This multi-dimensional arrangement allows the shafts to compress the magnet member radially between themselves and the jacket member, providing superior securing capability compared to traditional single-shaft configurations
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
The solution enables efficient, accurate, and repeatable manufacturing of high-efficiency permanent magnet electric motors with improved durability, reducing manufacturing complexity and costs.
Implementation Method 1
The shaft arrangement and the jacket member cooperate to compress the magnet member radially with respect to the axis of rotation
Data Source
AI summary
A rotor assembly for a permanent magnet electric motor defines an axis of rotation and includes a jacket member and a magnet member. The magnet member is received within the jacket member. The magnet member defines a central aperture with a first end and a second end. The axis of rotation extends through the first end and the second end. The rotor assembly further includes a shaft arrangement with a first shaft structure and a second shaft structure. The first shaft structure is received in the first end of the magnet member, and the second shaft structure is received in the second end of the magnet member. The first shaft structure and the second shaft structure are attached within the magnet member at an internal coupling. The shaft arrangement and the jacket member cooperate to compress the magnet member radially with respect to the axis of rotation.