Motor Stator Isolation via Dual-Diameter Sealing Barrier
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional sealing systems for motors in robotic manipulators fail to effectively isolate the stator from the rotor and position encoders in varying environmental conditions, such as vacuum, leading to issues like out-gassing and corrosion, which affect the efficiency and reliability of the robotic systems.
Innovation Solution
A sealing system comprising a housing, a motor with a stator and rotor, and an environment barrier with a one-piece sleeve member that extends between the stator and rotor, featuring a first seal interface connecting to the housing at a diameter less than or equal to the inner stator diameter and a second seal interface connecting at a diameter greater than or equal to the outer stator diameter, along with a position encoder integrated with the housing, where the environment barrier separates the stator from the rotor and encoders, using seals and barriers to maintain a hermetic seal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional sealing systems are used to connect the motor to the housing, then the structure is simpler, but the stator and rotor are not effectively isolated leading to out-gassing and corrosion in vacuum environments
Solution Approach 1:
The sealing system is divided into multiple independent seal interfaces (first seal interface at first diameter, second seal interface at second diameter) that create separate sealing zones. This segmentation allows each seal to independently prevent contamination, achieving reliable isolation without requiring a completely redesigned complex system
Solution Approach 2:
The environment barrier extends between the stator and rotor with seal interfaces at different diameters, creating a nested sealing structure where the barrier is positioned within the motor assembly. The first seal interface connects at a diameter less than or equal to the inner stator diameter, while the second seal interface connects at a diameter greater than or equal to the outer stator diameter, forming concentric sealing zones that effectively isolate the stator from rotor contaminants
2Object-affected harmful factors
If the stator and rotor are closely coupled for compact design, then the device size is reduced, but environmental contamination affects the stator from the rotor
Solution Approach 1:
The environment barrier acts as an intermediary component positioned between the stator and rotor. This barrier with its dual seal interfaces creates a protective zone that prevents harmful factors (out-gassing, corrosion) from the rotor environment from reaching the stator, while maintaining the compact motor structure
3Reliability
If seals are added to isolate components, then contamination is prevented, but heat removal efficiency decreases
Solution Approach 1:
The sealing system is designed with local quality by positioning seals at specific locations (first seal interface at first diameter, second seal interface at second diameter) rather than completely blocking heat paths. The seals are placed where they provide maximum contamination protection while minimizing interference with thermal conduction paths from the stator to the housing
Data Source
AI summary
An apparatus including a housing; a motor having a stator and a rotor, where the stator is connected to the housing; an environment barrier extending between the stator and the rotor; and a sealing system connecting the environment barrier with the housing. The sealing system includes a first seal interface and a second seal interface. The first seal interface connects to the housing at a first diameter which is at least partially less than or equal to an inner diameter of the stator. The second seal interface connects to the housing at a second diameter which is at least partially greater than or equal to an outer diameter of the stator.