Rotor Terminal Lamination Structure for Magnet Retention During Assembly
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
During the assembly of a rotor for an electric machine, there is a risk of rotor magnets falling or slipping out of the rotor laminated core due to gravity, particularly when the core is oriented vertically for magnet insertion and subsequent mounting on the rotor shaft.
Innovation Solution
The rotor laminated core features a terminal lamination with a recess that is axially aligned with the magnet pocket in the adjacent lamination, but narrowed to prevent magnet slipping or falling. This design ensures that the rotor magnet bears against the narrowing, preventing it from falling out during assembly, and allows for the flow of potting compound to avoid air pockets.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the rotor laminated core is oriented vertically for magnet insertion, then the magnet insertion process is simplified, but the rotor magnets may fall or slip out due to gravity
Solution Approach 1:
The terminal lamination is designed with a narrowing in the recess before magnet insertion, creating a mechanical stop that prevents magnets from falling out during vertical assembly. This preliminary structural preparation allows safe vertical orientation for insertion while preventing gravity-induced magnet displacement.
Solution Approach 2:
The recess in the terminal lamination is narrowed at its lower end, creating a localized structural feature that provides magnet retention. This local modification allows the majority of the recess to remain open for magnet insertion while the narrowed portion prevents magnet egress, resolving the contradiction between ease of insertion and magnet retention.
2Reliability
If the recess in the terminal lamination is narrowed to prevent magnet falling, then magnet retention is improved, but air pockets may form in the potting compound
Solution Approach 1:
The narrowing in the terminal lamination recess serves dual purposes: it prevents magnet falling while simultaneously creating a controlled exit path for air bubbles during potting. The narrowing acts as a one-way barrier that stops magnets but allows air to escape, converting a potential retention problem into a benefit for both magnet security and potting quality.
3Reliability
If the rotor magnets are secured with potting compound, then magnet retention is ensured, but air pockets may form reducing assembly quality
Solution Approach 1:
The narrowing in the terminal lamination recess acts as an intermediary structure between the magnet and the external environment. During potting, it serves as a controlled interface that allows air bubbles to escape while preventing magnet displacement, thereby ensuring both secure magnet retention and high assembly quality without air pockets.
Data Source
AI summary
A rotor laminated core for a rotor of an electric machine has a plurality of rotor laminations which are stacked axially one on the other and each have a recess. The recesses form a magnet pocket for receiving a rotor magnet. The rotor laminated core has a terminal lamination which is arranged on the axial side of the rotor laminated core and has a further recess which is axially aligned with the recess in the adjacent rotor lamination and is narrowed with respect to the recess in the adjacent rotor lamination.