Motor Coil End Insulation via Axial Offset and Radial Facing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional motors have intricate insulating sheet configurations due to three-dimensionally arranged coil ends, making the structure complex and difficult to simplify.

Innovation Solution

A motor design with a stator core featuring a ring-shaped yoke and radial teeth portions, where first and second coils are wound around these teeth but do not coincide in the axial direction, allowing an insulator to be placed between their facing portions such that either the first coil end is entirely covered or part of the second coil end is exposed, simplifying the insulator configuration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If coil ends are arranged three-dimensionally in radial and axial directions, then insulation between adjacent coils is achieved, but insulating sheet configuration becomes intricate and complex

Engineering Contradiction:
Improveinsulation between coilsVSAvoidinsulating sheet configuration
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent transitions from three-dimensional arrangement of coil ends to a two-dimensional planar arrangement by positioning first and second coil ends on the same end face of the stator core. This dimensional change eliminates the need for complex multi-layer insulating sheets, as insulation can now be achieved with simpler sheet configurations in a single plane.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

Instead of arranging coil ends in the conventional three-dimensional manner with outer and inner coils at different radial positions, the patent inverts the approach by placing both first and second coil ends on the same end face at different circumferential positions. This inversion simplifies the insulating sheet configuration while maintaining effective insulation.

Inventive Principle:
Principle #13The other way round (Inversion)

2Reliability

If multiple insulating sheets are used to cover different coil end portions, then insulation reliability is improved, but manufacturing complexity and assembly difficulty increase

Engineering Contradiction:
Improveinsulation reliabilityVSAvoidinsulator assembly
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent merges the insulation function into a single integrated insulating sheet that covers both first and second coil ends simultaneously. This is achieved by positioning the coil ends adjacently on the same end face, allowing one insulating sheet to perform the insulation function that previously required multiple separate sheets, thereby simplifying manufacturing and assembly.

Inventive Principle:
Principle #5Merging (Combining)

3Device complexity

If coil ends are positioned to face each other in radial direction, then insulator configuration is simplified, but coil winding space and electrical design flexibility are constrained

Engineering Contradiction:
Improveinsulator configurationVSAvoidcoil arrangement flexibility
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The patent segments the coil structure by dividing the winding into first and second coils with distinct coil ends positioned at different circumferential locations on the same end face. This segmentation allows the insulator configuration to be simplified while maintaining electrical design flexibility, as each coil can be independently designed and positioned.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3518392B1motor
Publication Date: 2021.12.08 DMG MORI CO LTD
  • EP3518392B1 patent drawingFigure 1~2
  • EP3518392B1 patent drawingFigure 3
  • EP3518392B1 patent drawingFigure 4

AI summary

A motor comprises a stator core (21), a first coil (31), and a second coil (41) provided adjacent to the first coil (31) in the radial direction. The first coil (31) and the second coil (41) do not coincide in position with each other as seen in the axial direction of the stator core (21). A first coil end portion (36) of the first coil (31) and a second coil end portion (46) of the second coil (41) respectively include a first facing portion (38) and a second facing portion (48) facing each other in the radial direction. The motor (100) further comprises an out-slot insulator (51) interposed at least between the first facing portion (38) and the second facing portion (48) and provided so that at least a part of the first coil end portion (36) and the second coil end portion (46) is exposed. With this configuration, a motor is provided that allows a simplified configuration of the insulator for insulating the coil end portions from each other.