Single-Phase Brushless Motor Volume Reduction via Segmented Stator

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Solution Overview

Problem

Existing single-phase brushless motors have a larger volume due to reduced effective space in stator coils, making them unsuitable for miniaturization requirements.

Innovation Solution

A mounting structure comprising a stator assembly and a rotor assembly is optimized, with the stator coils wound around a coil bobbin, and magnetic yokes inserted into a through hole, forming an inner hole, and an uneven air gap between the stator and rotor assemblies, which reduces iron and copper losses and increases efficiency, allowing for a smaller motor volume.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If stator coils are wound around stator teeth, then the motor can be constructed with traditional winding method, but the effective space of windings is reduced leading to larger motor volume

Engineering Contradiction:
Improvewinding constructionVSAvoidmotor volume
Core Design Contradiction:
Ease of manufactureVSVolume of moving object

Solution Approach 1:

The stator core is divided into two separate core blocks with U-shaped and inverted U-shaped structures. These segmented core blocks are assembled together to form the complete stator, allowing coils to be wound on the coil bobbin before assembly. This segmentation enables better space utilization and reduces the overall motor volume while maintaining traditional winding advantages.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The coil bobbin is inserted into the coil-receiving recess of the core blocks, and the core blocks are then assembled together to form the complete stator assembly. This nested structure allows efficient use of space and reduces motor volume while maintaining the effectiveness of the winding arrangement.

Inventive Principle:
Principle #7Nested doll (Nesting)

2Device complexity

If traditional stator structure is used, then the motor structure is simple, but the motor volume is larger and cannot meet miniaturization requirements

Engineering Contradiction:
Improvestator structureVSAvoidmotor volume
Core Design Contradiction:
Device complexityVSVolume of moving object

Solution Approach 1:

The stator is segmented into two core blocks that can be assembled together. This segmentation allows for more compact arrangement of magnetic paths and windings, reducing the overall motor volume while maintaining structural simplicity through modular assembly.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention utilizes a three-dimensional assembly approach where the two core blocks are positioned at opposite ends of the coil bobbin and connected through magnetic yokes. This spatial arrangement optimizes the use of available space and achieves miniaturization while keeping the structure relatively simple.

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

3Loss of energy

If efficiency is improved through optimized electromagnetic circuit, then power consumption decreases, but the structural complexity increases

Engineering Contradiction:
Improveiron loss and copper lossVSAvoidmounting structure
Core Design Contradiction:
Loss of energyVSDevice complexity

Solution Approach 1:

The invention introduces localized features such as ventilation slots in the tooth portions and an uneven air gap between stator and rotor assemblies. These local modifications optimize the electromagnetic circuit and improve efficiency by reducing losses, while the overall structure remains relatively simple through targeted rather than comprehensive redesign.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The invention optimizes the air gap configuration between stator and rotor assemblies by creating an uneven air gap rather than a uniform one. This parameter change improves the electromagnetic circuit efficiency and reduces losses without requiring complex additional structures.

Inventive Principle:
Principle #35Parameter changes

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

The optimized structure decreases the motor's volume while maintaining or improving efficiency, meeting the miniaturization requirements of single-phase brushless motors.

Implementation Method 1

Motors, which are devices that convert electric energy into mechanical energy under the principle of electromagnetic induction

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

magnets having two poles... the rotor assembly comprises an integral bearing, one end of the integral bearing being connected to an impeller, and the other end being mounted around the magnets

Methodology Applied
Scientific EffectMagnetic field interaction: Magnetic Field

Data Source

PatentEP3796521B1A single-phase brushless high-speed motor
Publication Date: 2022.08.31 ONCE TOP MOTOR MFG CO LTD
  • EP3796521B1 patent drawingFigure 1~2
  • EP3796521B1 patent drawingFigure 3
  • EP3796521B1 patent drawingFigure 4

AI summary

The present invention relates to the technical field of brushless motor. Disclosed herein is a single phase brushless high-speed motor, comprising: an outer housing, a stator assembly, and a rotor assembly; the stator assembly including a coil bobbin, stator coils and a stator core; a coil-receiving recess being arranged on the outer surface of the coil bobbin and a through hole being defined in the central part of the coil bobbin for connection; the stator core including two W-shaped core blocks, which comprise tooth portions, two opposite ends of the tooth portions being provided with a first magnetic yoke and a second magnetic yoke; the tooth portions of the stator core being engaged with each other to form an inner hole of the stator; the first magnetic yoke and second magnetic yoke of the stator core being inserted into the through hole of the coil bobbin respectively from both sides, thereby forming the stator assembly; the rotor assembly comprising an integral bearing, one end of the integral bearing being connected to an impeller, and the other end being mounted around magnets, which form magnetic body having two poles; wherein a Printed Circuit Board (PCB) assembly is mounted on the coil bobbin. The volume of the single-phase brushless motor is decreased and the requirements for the miniaturization of single-phase brushless motors are satisfied by arranging a mounting structure comprising a stator assembly and a rotor assembly.