Stator Teeth Stack Bridge Removal for Flux Linkage

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional methods for producing stators for synchronous permanent magnet machines are costly and labor-intensive due to the need for complex interconnections between laminated teeth and yokes, which can lead to reduced flux linkage and efficiency.

Innovation Solution

A method involving a teeth stack with radially arranged teeth forming a circular structure, interconnected by bridges that are later removed, and inserted into a yoke stack with a sealing compound to form a solid unit, allowing for a simpler assembly and increased electromagnetic force.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If conventional methods use complex interconnections between laminated teeth and yokes, then structural stability is improved, but production cost and complexity increase significantly

Engineering Contradiction:
Improvestructural stabilityVSAvoidproduction complexity
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The invention divides the stator into modular components: a yoke with yoke segments and a teeth stack with teeth segments. These segmented components can be manufactured separately and assembled together, simplifying production while maintaining structural stability through the modular design and interlocking segments.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The teeth stack and yoke are prepared in advance as separate pre-assembled units with their respective segments and connections already in place. This preliminary preparation allows for easier final assembly and reduces production complexity during the main assembly process.

Inventive Principle:
Principle #10Preliminary action

2Stability of the object's composition

If conventional methods use complex interconnections between laminated teeth and yokes, then structural stability is improved, but production time increases

Engineering Contradiction:
Improvestructural stabilityVSAvoidproduction efficiency
Core Design Contradiction:
Stability of the object's compositionVSProductivity

Solution Approach 1:

By segmenting the teeth and yoke into separate manufacturable units that can be produced independently and assembled efficiently, the invention reduces production time while maintaining the structural stability needed for motor operation.

Inventive Principle:
Principle #1Segmentation

3Strength

If bridges are used to interconnect adjacent teeth, then mechanical strength is improved, but flux linkage is reduced due to short-circuiting

Engineering Contradiction:
Improvemechanical strengthVSAvoidflux linkage loss
Core Design Contradiction:
StrengthVSLoss of energy

Solution Approach 1:

The invention removes or extracts the bridges that interconnect adjacent teeth, eliminating the harmful short-circuiting effect that reduces flux linkage. The teeth are left as separate entities, improving electromagnetic performance while maintaining structural integrity through alternative design features.

Inventive Principle:
Principle #2Taking out (Extraction)

4Stability of the object's composition

If conventional assembly methods are used, then structural integrity is maintained, but assembly complexity increases

Engineering Contradiction:
Improvestructural integrityVSAvoidassembly ease
Core Design Contradiction:
Stability of the object's compositionVSEase of manufacture

Solution Approach 1:

The segmented design allows the stator to be assembled from discrete, pre-prepared components (yoke segments and teeth segments) that can be easily positioned and connected, simplifying the assembly process while maintaining structural integrity through the modular construction.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3477819B1Method for producing a stator, and teeth stack for a stator
Publication Date: 2021.02.24 ROBERT BOSCH GMBH
  • EP3477819B1 patent drawingFigure 1A~1B
  • EP3477819B1 patent drawingFigure 1C~1D
  • EP3477819B1 patent drawingFigure 1E

AI summary

The invention relates to a method for producing a stator (100, 300, 400) for a synchronous permanent magnet machine, the method comprising a step of providing a teeth stack (110) comprising several teeth (111), wherein the teeth (111) are arranged in a radial direction forming the teeth stack (110) as a circular structure, wherein the teeth (111) each comprise a root end (113) in a radially outward direction of the teeth stack (110) and an inner end (115) in a radially inward direction of the teeth stack (110) and wherein each two adjacent teeth (111) form a gap (111a) in-between and wherein the inner ends (115) of the adjacent teeth (111) are interconnected by means of bridges (114); and a step of providing at least one coil (130, 430) in at least one of the gaps (111a) between adjacent teeth (111) of the teeth stack (110). The method further comprises a step of arranging the teeth stack (110) within a yoke stack (120, 320, 420) such that the root ends (113) of the teeth (111) are in mechanical contact with the yoke stack (120, 320, 420), and a step of removing at least a part of the bridges (114) at the inner end (115) of the teeth (111) such that the teeth stack (110) has a predetermined diameter (152) in the radially inward direction. The invention further relates to a stator (100, 300, 400), a teeth stack (110) and a synchronous permanent magnet machine having a stator (100, 300, 400).