Stator Winding with Protruding Insulating Paper

Solution Overview

Problem

Existing methods for inserting coils into stators in electric drives are time-consuming and costly, and do not fully utilize the coil space, leading to inefficiencies in power output and size constraints, particularly in power tools where a smaller diameter is desired without compromising performance.

Innovation Solution

An automated method using a torsion winding arm to insert coil wire into a stator coil space with insulating paper that protrudes beyond the pole horns, ensuring electrical safety and abrasion protection, allowing for a higher packing density and increased performance with a reduced stator size.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If manual insertion of pre-wound coils is used, then coil insertion is possible, but the process is time-consuming and costly

Engineering Contradiction:

Core Design Contradiction:

Ease of manufactureVSProductivity

Solution Approach 1:

The coil wire is prepared in advance with a fixing means (adhesive coating) applied to individual turns before insertion. This preliminary action allows the coil to be quickly inserted and fixed in the coil space without time-consuming manual wrapping or bandaging operations, thereby increasing productivity while maintaining ease of manufacture

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

A fixing means (adhesive substance) is introduced as an intermediary between the coil wire turns and the coil space. This intermediary enables rapid fixation of the coil in the inserted position without requiring complex manual operations, resolving the contradiction between ease of manufacture and productivity

Inventive Principle:

Principle #24Intermediary (Mediator)

2Ease of manufacture

If pre-wound bobbins are used, then coil insertion is simplified, but the bobbin space cannot be fully utilized

Engineering Contradiction:

Core Design Contradiction:

Ease of manufactureVSQuantity of substance

Solution Approach 1:

The coil wire is prepared in advance with fixing means applied to individual turns, allowing it to be densely packed into the coil space without the gaps that occur with pre-wound bobbins. This preliminary preparation enables both ease of insertion and full utilization of the available coil space

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The coil wire is inserted in a flexible state and then fixed in position using the fixing means, allowing it to conform exactly to the coil space geometry. This parameter change from rigid pre-wound bobbin to flexible insertable wire enables complete space utilization while maintaining manufacturing simplicity

Inventive Principle:

Principle #35Parameter changes

3Device complexity

If air cooling is used, then cooling is simple, but dust particles cause abrasion of the coil wire

Engineering Contradiction:

Core Design Contradiction:

Device complexityVSObject-affected harmful factors

Solution Approach 1:

Individual turns of the coil wire are coated with a fixing means (adhesive substance) before insertion, creating a protective cushion that binds the turns together. This beforehand cushioning protects the coil wire from dust particle abrasion during operation, while the cooling system remains simple air cooling without requiring filtration or sealed enclosures

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This method enables a higher degree of filling in the coil slots, maintaining the required electrical safety distance and providing effective abrasion protection, resulting in increased power output and reduced size of electric motors, specifically allowing for a smaller diameter while maintaining performance.

Implementation Method 1

fixing means for fixing individual turns of the inserted coil wire to one another

Methodology Applied

Scientific EffectAdhesion: Adhesive

Implementation Method 2

insulating paper that protrudes beyond the pole horns, ensuring electrical safety

Methodology Applied

Scientific EffectElectrical insulation: Dielectric

Implementation Method 3

protruding beyond the pole horns, ensuring electrical safety and abrasion protection

Methodology Applied

Scientific EffectAbrasion protection: Abrasion

Data Source

PatentEP2605384B1Method for winding the field coils of a stator and this stator

Publication Date: 2019.10.16

Figure 1~2
Figure 3
Figure 4~5a

AI summary

The method involves inserting an insulating paper into a coil space such that the insulating paper projects from coil grooves in a direction perpendicular to a longitudinal axis (L) of a stator (10) over pole horns (16) within a range of 5-15 mm, where the coil space is limited by the pole horns and a stator wall of the stator. A coil wire (20) is inserted into the coil space using a rotary winding arm. A projecting portion of the insulating paper is drawn radially inside without interfering the insertion of the coil wire. The insulating paper is fixed at a stator body and the inserted wire. Independent claims are also included for the following: (1) a stator for an electric drive (2) a device for manufacturing a stator.