Radial-Coil Stepper Motor Layout for Compact Torque Output
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing stepper motors face challenges in reducing their radial size due to the thicknesses of coils, claw poles, and magnetic steel, hindering the development of lightweight and compact designs.
Innovation Solution
A stepper motor design with a rotor assembly and stacked stator assemblies, where solenoids and coils are arranged along the radial direction of the rotatory shaft, utilizing a claw pole assembly and housing configuration to minimize radial thickness and enhance torque performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If coils, claw poles, and magnetic steel are arranged in conventional axial configuration, then motor function is maintained, but radial size cannot be reduced
Solution Approach 1:
The patent applies dimensionality change by reorienting the coil arrangement from axial to radial direction. The coil's central axis extends along the radial direction of the rotatory shaft, transforming the conventional three-dimensional arrangement into a more space-efficient configuration that reduces radial thickness while maintaining functional performance.
Solution Approach 2:
The patent implements nesting by placing the coil inside the claw pole assembly structure. The coil is positioned within the radial space of the claw pole, allowing multiple components to occupy overlapping spatial regions and thereby reducing the overall radial envelope of the motor.
2Volume of moving object
If coil thickness is reduced to decrease radial size, then radial dimension improves, but torque performance deteriorates
Solution Approach 1:
The patent applies parameter changes by modifying the geometric orientation of the coil from axial to radial alignment. This parameter change allows the coil to generate equivalent or superior torque with reduced radial thickness, as the radial orientation optimizes the magnetic field interaction with the rotor magnets.
Solution Approach 2:
The patent implements local quality optimization by concentrating the magnetic field generation in the radial direction where it is most effective for torque production. The coil's radial orientation creates a localized high-density magnetic field interaction zone that maximizes torque density per unit radial thickness.
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 design reduces the motor's radial size, enabling a lightweight and compact structure while improving torque performance and stability by optimizing coil placement and magnetic field distribution.
Implementation Method 1
each solenoid of the respective plurality of solenoids includes a respective iron core and a respective coil wound on the respective iron core
Implementation Method 2
a plurality of magnetic steels arranged along circumference of the rotatory shaft
Implementation Method 3
each stator assembly of the one or more stator assemblies is sleeved on the rotor assembly and includes a respective claw pole assembly arranged around circumference of the rotor assembly, a respective plurality of solenoids arranged along circumference of the respective claw pole assembly
Data Source
AI summary
The present disclosure provides a stepper motor, which belongs to the field of motor technology. The stepper motor includes: a rotor assembly including a rotatory shaft and a plurality of magnetic steels arranged along circumference of the rotatory shaft; and one or more stator assemblies stacked along an axial direction of the rotor assembly. Each stator assembly is sleeved on the rotor assembly and includes a respective claw pole assembly arranged around circumference of the rotor assembly, a respective plurality of solenoids arranged along circumference of the respective claw pole assembly, and a respective housing configured to accommodate the respective claw pole assembly and the respective plurality of solenoids. Each solenoid includes a respective iron core and a respective coil wound on the respective iron core, and a central axis of the respective coil extends along a radial direction of the rotatory shaft.