Brushless Motor Stator Radial Dimension Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing brushless motors face challenges with increased radial dimension due to lead wire routing along the radial direction, require multiple terminals for each coil, and inefficient winding operations as each coil needs separate lead wires, limiting manufacturing ease and automation.

Innovation Solution

The design reorients the terminal fixing block's puncture notch along the circumference of the upper insulating bobbin, allowing lead wires to be routed along the circumference, reducing the radial dimension, and uses a single lead wire to wind all coil groups, sharing terminals and optimizing space for component arrangement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If lead wires are routed along the radial direction of the upper insulating bobbin, then terminal fixing is simplified, but the radial dimension of the stator increases

Engineering Contradiction:
Improveterminal fixing simplicityVSAvoidradial dimension of stator
Core Design Contradiction:
Ease of manufactureVSLength of stationary object

Solution Approach 1:

The patent inverts the conventional radial routing approach by routing lead wires along the circumferential direction of the upper insulating bobbin instead. The terminal fixing block is positioned on the circumferential side, and lead wires are guided through circumferential grooves, reversing the traditional radial arrangement to reduce radial dimension while maintaining manufacturing simplicity

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

Solution Approach 2:

The patent transitions from radial (one-dimensional) lead wire routing to circumferential routing, effectively utilizing a different spatial dimension. By arranging terminal fixing blocks and grooves along the circumferential direction rather than radially, the design optimizes space utilization and reduces the radial footprint of the stator

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

2Ease of operation

If each coil is wound with separate lead wires, then winding operations are straightforward, but the number of terminals increases and manufacturing efficiency decreases

Engineering Contradiction:
Improvewinding operation simplicityVSAvoidmanufacturing efficiency
Core Design Contradiction:
Ease of operationVSProductivity

Solution Approach 1:

The patent merges multiple separate lead wire routing operations into a single integrated circumferential routing path. By positioning terminal fixing blocks along the circumferential direction and using continuous grooves, multiple coils can be wound and connected through a unified lead wire arrangement, reducing the total number of terminals and improving manufacturing efficiency

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The circumferential lead wire routing system serves multiple functions simultaneously: it provides terminal fixation, guides lead wires through all coils, and enables efficient electrical connections. This multi-functional design replaces the need for separate terminal fixtures and routing mechanisms for each coil, streamlining the manufacturing process

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

Data Source

PatentEP3323188B1Stator with insulating bobbin in a brushless motor
Publication Date: 2021.10.20 BERGSTROM INC
  • EP3323188B1 patent drawingFigure 1
  • EP3323188B1 patent drawingFigure 2
  • EP3323188B1 patent drawingFigure 3

AI summary

A brushless motor includes a stator core having a plurality of tooth portions; a lower insulating bobbin connected to a lower face of the stator core, the lower insulating bobbin having a plurality of lower slot insulation portions each corresponding to a respective tooth portion; and an upper insulating bobbin connected to an upper face of the stator core, the upper insulating bobbin having a plurality of upper slot insulation portions each corresponding to a respective tooth portions such that the upper slot insulation portions, the tooth portions, and the lower slot insulation portions define a plurality of coil wound portions. The plurality of coil wound portions includes at least one group of coil wound portions with each group having first to sixth coil wound portions. All of the coil wound portions of all groups are wound by a single lead wire.