Step-Shaped Stator Teeth for Bobbinless Motor Winding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In electric motors for compressors, the use of coil bobbins increases the axial dimension, making it difficult to reduce motor size, and coil bobbin-less configurations risk coating damage or disconnection due to sharp edges on the stator core, compromising winding quality.
Innovation Solution
The motor features a stator core with annular electromagnetic steel sheets where the tooth portions' circumferential widths gradually narrow towards the ends, allowing direct winding without bobbins, and uses thin insulating members to prevent damage and disconnection, with flexible insulating sheets that can deform to follow the shoulder portion shape.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If coil bobbins are installed at both end sites of the stator core, then the coil winding is protected during winding, but the axial dimension of the stator increases, causing an increase in motor size
Solution Approach 1:
The invention removes the coil bobbin component entirely from the stator structure. Instead of using traditional coil bobbins that increase axial dimension, the patent extracts this element and replaces it with a modified stator core design featuring rounded shoulder portions that directly guide and protect the coil winding during the winding process, thereby reducing the axial dimension while maintaining winding quality
Solution Approach 2:
The invention introduces rounded shoulder portions on the stator core teeth as intermediary structures. These rounded portions serve as mediators between the coil winding and the sharp edges of the stator core, providing a smooth transition surface that guides the coil winding during winding without requiring separate coil bobbin components, thus solving both the protection and size reduction requirements
2Length of moving object
If coil bobbins are removed to reduce axial dimension, then motor size is reduced, but coating damage or disconnection of coil winding may occur due to sharp edges on stator core
Solution Approach 1:
The invention applies spheroidality by rounding the shoulder portions on the stator core teeth. Instead of sharp edges that could damage the coil winding coating or cause disconnection, the rounded surfaces provide a smooth curvature that guides the coil winding safely during the winding process, eliminating the harmful effects of sharp edges while maintaining the coil bobbin-less design for compact size
3Device complexity
If coil bobbins are installed, then the motor structure is simplified with single-piece stator core, but the axial dimension and overall motor size increase
Solution Approach 1:
The invention extracts and removes the coil bobbin component from the stator assembly. By eliminating this separate component and integrating its guiding and protective functions directly into the stator core structure through rounded shoulder portions, the design achieves structural simplification without the axial dimension penalty of traditional coil bobbin installations
Data Source
AI summary
A method for producing an electric motor provided with a stator core configured by laminating a required number of annular electromagnetic steel sheets having a plurality of tooth portions on an inner periphery thereof. The circumferential widths of the tooth portions become gradually narrower in a stepwise fashion toward an uppermost surface and an undermost surface of the plurality of laminated electromagnetic steel sheets, whereby the shoulder portions on both sides in a circumferential direction of the tooth portions smoothly change. A flexible, planar insulating member is provided having a first portion of a shape similar to a planar shape of said electromagnetic steel sheet, and further comprising flexible ear portions at positions corresponding to shoulder portions on both sides in a circumferential direction of the tooth portions. A coil is wound around the flexible planar insulating member and the respective tooth portions, including the ear portions of said insulating member interposed between the coil winding and the tooth portion, to thereby deform the flexible ear portions to conform the shape of the shoulder portions.