Segmented Rotor Structure for Magnet Clamping at High Speed
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rotors of electric machines require high-strength, expensive fibers for magnet clamping, leading to increased manufacturing time and cost, and are prone to deformation under speed load.
Innovation Solution
The rotor design incorporates multiple base bodies arranged circumferentially with radial separations allowing radial movement, clamped by an oversize rotor support or tensioned rotor sleeve, enabling preassembly and reduced deformation, and includes magnetic cooling channels for improved magnet retention and cooling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If high-strength fibers are used for magnet clamping, then magnet retention is improved, but manufacturing cost increases
Solution Approach 1:
The rotor body is divided into multiple base bodies arranged circumferentially with radial separations between them. This segmentation allows the use of standard-strength fibers in the rotor sleeve while achieving effective magnet clamping through the cumulative effect of multiple base bodies working together, thereby reducing manufacturing cost without compromising magnet retention.
Solution Approach 2:
The base bodies are pre-assembled with clearance fit into the rotor sleeve before the rotor support is inserted. This preliminary arrangement allows the oversize rotor support to generate the necessary preload when pressed in, clamping the magnets effectively without requiring high-strength fibers during the assembly process.
2Reliability
If fibers are wound separately for each rotor, then magnet clamping is achieved, but manufacturing time increases
Solution Approach 1:
The rotor sleeve is pre-assembled independently of individual rotors with base bodies inserted in clearance fit. This pre-assembly can be performed in advance and then divided into multiple rotor sleeves, enabling batch manufacturing and significantly reducing the time required for each individual rotor assembly.
Solution Approach 2:
Multiple base bodies are combined in a single rotor assembly with the pre-assembled rotor sleeve. This merging approach allows the rotor support to be inserted and press all base bodies simultaneously into position, achieving magnet clamping for multiple magnets in one operation rather than winding fibers separately for each rotor.
3Speed
If high preloads are applied to reduce deformation, then rotor speed capability is improved, but manufacturing complexity increases
Solution Approach 1:
The rotor body is segmented into multiple base bodies that can be independently positioned and clamped. This segmentation allows the oversize rotor support to distribute the preload evenly across multiple base bodies when pressed in, achieving high preloads necessary for high-speed operation without requiring complex manufacturing processes.
Solution Approach 2:
The rotor support is designed with an oversize parameter that enables it to generate the necessary preload when pressed into the assembled rotor body. This parameter change from exact fit to oversize allows simple pressing operation to achieve the high preloads needed for high-speed rotor operation, reducing deformation under speed load.
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 design simplifies magnet clamping, allows higher preloads, reduces deformation, and enables higher speeds with lower manufacturing costs, while maintaining effective magnet retention and cooling.
Implementation Method 1
by means of an oversize of the rotor support according to a first embodiment
Implementation Method 2
the base bodies are moved in the radial direction towards the rotor sleeve when the rotor support is inserted into the rotor body due to an oversize of the rotor support
Implementation Method 3
by winding the rotor sleeve under tension according to a second embodiment
Implementation Method 4
a preload is generated in the rotor sleeve due to a deformation of the rotor sleeve
Implementation Method 5
a rotor sleeve, which is pre-assembled independently of the individual rotor, has the advantage that it can be manufactured with a multiple length of the rotor and then divided into multiple rotor sleeves
Data Source
AI summary
The invention relates to a rotor (2) of an electric machine (1), comprising a rotor support (4), in particular a rotor shaft, which can be rotated about a rotor axis (3), a rotor sleeve (5), in particular a fiber composite sleeve, and a rotor body (6) which is arranged between the rotor support (4) and the rotor sleeve (5) and which comprises multiple rotor poles (7) and at least one magnet pocket (8) per rotor pole (7) for receiving magnets (9), in particular permanent magnets. The rotor body (6) has at least one base body (10), said base body being supported on the rotor support (4) radially inside the magnet pockets (8) with respect to the rotor axis (3), and outer segment bodies (11) radially outside the magnet pockets (8). The invention is characterized in that—multiple base bodies (10) are provided one behind the other in a circumferential direction,—a radial separation (14) which is continuous in the radial direction is formed between each pair of adjacent base bodies (10) in the region radially within each magnet pocket (8) in order to allow a radial movement of the base bodies (10), and—the base bodies (10) can be clamped between the rotor support (4) and the rotor sleeve (5) in order to clamp the magnets (9) in the magnet pockets (8), in particular by virtue of an oversize of the rotor support (4) or by winding the rotor sleeve (5) under tension.