Bar Winding Group Assembly for Variable Hairpin Alignment

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing assembly methods for bar windings in electric machines are limited in their ability to handle conductors with non-circular cross-sections and varying leg lengths, requiring additional gripper assemblies for insertion into stator or rotor cores, and are not adaptable for assembling windings with different hairpin spans or pitches.

Innovation Solution

An assembly apparatus featuring an annular fixture with slots and a conductor insertion device that allows for the precise alignment and insertion of bar conductors with varying leg lengths and cross-sections, using a guiding device to manage the legs and a moving device to rotate them into position, eliminating the need for additional gripper assemblies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional assembly methods are used for bar windings, then round wire conductors can be assembled, but conductors with non-circular cross-sections (rectangular, trapezoidal) cannot be properly handled

Engineering Contradiction:
Improveability to handle different conductor cross-sectionsVSAvoidassembly apparatus configuration
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The assembly apparatus is designed with a universal fixture system that can accommodate multiple conductor types (round wire, rectangular, trapezoidal) through adjustable clamping mechanisms and interchangeable insertion tools, allowing a single device to perform multiple conductor assembly functions without requiring separate specialized equipment for each conductor geometry

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If additional gripper assemblies are used to insert conductors into stator or rotor cores, then conductors with varying leg lengths can be handled, but the assembly process becomes more complex

Engineering Contradiction:
Improveability to handle varying leg lengthsVSAvoidnumber of gripper assemblies
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The apparatus combines the gripping function and the insertion function into a single integrated mechanism. The fixture system incorporates adjustable clamps that can grip conductors of different leg lengths, and the insertion device is designed to work with these clamps to push conductors into the core, eliminating the need for separate gripper assemblies for each conductor variation

Inventive Principle:
Principle #5Merging (Combining)

3Manufacturing precision

If conventional fixtures are used, then assembly can proceed, but alignment precision for conductors with different hairpin spans and pitches cannot be achieved

Engineering Contradiction:
Improvealignment precision for different hairpin spansVSAvoidfixture configuration
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The fixture system incorporates adjustable and reconfigurable elements that can be dynamically positioned to match different hairpin spans and pitches. The fixture includes movable guides and adjustable spacing mechanisms that can be reconfigured for each conductor type, allowing precise alignment without requiring completely different fixtures for each span variation

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP3791462B1Assembly and method of assemblage for a winding group of a bar winding for an electric machine
Publication Date: 2023.12.20 TECNOMATIC
  • EP3791462B1 patent drawingFigure 1~2
  • EP3791462B1 patent drawingFigure 3~4
  • EP3791462B1 patent drawingFigure 5~6

AI summary

An assembly for assembling at least one winding group of a bar winding for an electric machine, said winding group (2) comprising a plurality of bar conductors (4), each bar conductor (4) of said plurality of bar conductors (4) comprising a first leg (6), a second leg (8) and a bridge portion (10) connecting said first leg (6) and said second leg (8) to each other, each of said bar conductors being shaped so that the respective legs (6, 8) are mutually spread by a predetermined distance; - said assembly comprises an annular fixture (12) delimiting a plurality of slots, each slot (16) being adapted to receive at least one portion of either said first leg (6) or said second leg (8), said assembly comprises at least one guiding device (28) which defines an annular containment housing (30), adapted to receive at least partially the legs (6, 8) of said plurality of legs (6,8) of said plurality of bar conductors (4) when they are housed in said plurality of slots (16, 16', 16"), forming at least one radial containment wall (39, 40) for said legs (6, 8).