Multi-Layer Rotor Sleeve Structure for Uniform Pressurizing Force
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rotor designs face challenges in efficiently applying a pressurizing force to the rotor core while maintaining a thin sleeve structure, as the circumferential stress distribution in a single-layer sleeve structure is uneven, leading to inadequate support for permanent magnets during high-speed rotation.
Innovation Solution
A rotor manufacturing method involving a multi-layer sleeve structure, where each layer is fitted with a specific inner diameter to equalize circumferential stress, using a liquid-pressure expansion press-in method to laminate multiple sleeve layers, ensuring uniform pressurizing force application.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single-layer sleeve structure is used, then the device complexity is reduced, but the pressurizing force applied to the rotor core is insufficient and the sleeve thickness cannot be reduced
Solution Approach 1:
The sleeve is divided into multiple layers (first sleeve layer and second sleeve layer) with different functional characteristics. The first sleeve layer provides initial pressurizing force, while the second sleeve layer enhances and distributes this force more effectively, resolving the contradiction between structural simplicity and pressurizing force sufficiency.
Solution Approach 2:
The sleeve employs a composite multi-layer structure where each layer can be made of different materials or have different structural properties. This composite approach allows optimization of pressurizing force distribution while managing sleeve thickness, addressing both the force insufficiency and thickness reduction requirements.
2Ease of manufacture
If a single-layer sleeve structure is used, then the manufacturing process is simplified, but the circumferential stress is not efficiently distributed and the pressurizing force cannot be effectively applied to the outer peripheral portion
Solution Approach 1:
The sleeve is segmented into multiple layers with the second sleeve layer positioned to specifically address stress distribution at the outer peripheral portion. This segmentation allows each layer to be manufactured separately with optimized characteristics, then assembled to achieve superior stress distribution overall.
Solution Approach 2:
The second sleeve layer is designed with specific local properties to enhance circumferential stress distribution at critical regions (outer peripheral portion). By concentrating enhanced stress distribution capabilities where needed, the multi-layer structure achieves superior local performance without excessive overall complexity.
3Weight of moving object
If the sleeve thickness is reduced, then the rotor weight and inertia are decreased, but the pressurizing force becomes insufficient to counteract centrifugal force
Solution Approach 1:
The multi-layer sleeve structure acts as a composite system where the first and second sleeve layers work together to provide sufficient pressurizing force. This composite approach allows the overall sleeve thickness to be reduced while maintaining or enhancing the effective pressurizing force through optimized layer configuration and material properties.
Solution Approach 2:
By segmenting the sleeve into multiple functional layers, each layer can be optimized for specific purposes. The combined effect of multiple thinner layers provides equivalent or superior pressurizing force compared to a single thick layer, reducing overall weight and inertia while maintaining force sufficiency.
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 multi-layer sleeve design enhances the pressurizing force efficiency and allows for higher rotational speeds by evenly distributing stress, reducing sleeve thickness and improving the rotor's operational performance.
Implementation Method 1
the difference between the circumferential stress in the second sleeve layer and the circumferential stress in the first sleeve layer can be suppressed
Implementation Method 2
configured to apply a pressurizing force directed radially inward to the plurality of permanent magnets
Implementation Method 3
When the rotor rotates, the sleeve and the resin prevent the permanent magnets from moving radially outward due to centrifugal force
Data Source
AI summary
A sleeve of a rotor includes a first sleeve layer and a second sleeve layer. The first sleeve layer is arranged on the most radially inward and fitted to an outer peripheral portion of a rotor body. The second sleeve layer is arranged radially outward of the first sleeve layer and fitted thereto. In a fitting step, the outer peripheral portion of the rotor body is pressed and fitted into a first sleeve layer having a first inner diameter that is smaller than an outer diameter of the outer peripheral portion. Then, a first outer peripheral portion of the first sleeve layer fitted to the outer peripheral portion of the rotor body is pressed into a second sleeve layer having a second inner diameter that is smaller than a first outer diameter of the first sleeve layer, and fitted to the second sleeve layer.