Rotor, motor, and compressor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional rotors experience vibration due to sudden changes in the air gap and electromagnetic force between the rotor and stator, which are not adequately addressed in existing designs.
Innovation Solution
A rotor design featuring a first arc portion, a straight line portion, and a curved portion with a second arc portion that smoothly connects these, reducing the sudden change in air gap and electromagnetic force, thereby minimizing vibration and fluid resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If an outer shape of one pole of the rotor is composed of a curve of a hyperbolic cosine function, then output torque increases and inductance decreases, but the air gap increases exponentially causing sudden changes in electromagnetic force and generating higher-order electromagnetic force that causes vibration
Solution Approach 1:
The patent modifies the rotor's outer shape parameters by replacing the hyperbolic cosine curve with a composite curve consisting of a first arc portion, a straight line portion, and a curved portion with a second arc portion. This parameter change in the geometric configuration allows the air gap to increase linearly rather than exponentially, suppressing sudden changes in electromagnetic force while maintaining the desired output torque and inductance characteristics
Solution Approach 2:
The patent applies curvature principles by designing the rotor outer shape with specific arc portions having defined radii of curvature. The first arc portion has a radius of curvature R1, and the curved portion includes a second arc portion with radius of curvature R2 where R2 < R1. This controlled curvature distribution ensures smooth transitions in the air gap, preventing abrupt electromagnetic force changes that cause vibration
2Quantity of substance
If the air gap increases exponentially as distance from the center increases, then inductance decreases, but electromagnetic force changes abruptly at the end of the outer shape causing higher-order electromagnetic force and vibration
Solution Approach 1:
The patent changes the functional relationship of the air gap from exponential to linear by redesigning the rotor outer shape. The composite curve (first arc portion + straight line portion + curved portion) ensures that the air gap increases linearly with distance from the center, which maintains appropriate inductance levels while preventing abrupt electromagnetic force changes that generate vibration
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 rotor effectively suppresses vibration and reduces fluid resistance during rotation by maintaining a consistent air gap and smoothly connecting the arc portions, enhancing the motor's performance and reducing noise.
Implementation Method 1
electromagnetic force generated between the rotor and the stator
Data Source
AI summary
A rotor includes a rotor core. The rotor core has an outer shape including a first arc portion provided so as to intersect a d-axis, a straight line portion provided so as to intersect a q-axis, and a curved portion that connects the first arc portion and the straight line portion. The first arc portion has an arc shape centered on an axial center of the rotor core. The curved portion includes an arc-shaped second arc portion that bulges outward in a radial direction of the rotor core. The radius of curvature of the second arc portion being smaller than a radius of curvature of the first arc portion.