Motor Unit Seal Design for Moisture Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional motor assemblies with through-holes in the cover allow moisture to enter the housing, potentially leading to malfunction and deterioration of the motor and controller.
Innovation Solution
A motor assembly design that includes a seal between the inner edge of the through-hole and the connector portion, with a groove on the cover's obverse surface communicating with the through-hole to direct water droplets away from the seal, and a labyrinthine gap between the housing body and cover to prevent moisture intrusion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a through-hole is formed in the cover to allow the connector portion to pass through, then the connector can be connected to the external terminal, but moisture can enter the housing through the through-hole
Solution Approach 1:
A seal member is introduced as an intermediary component between the cover and the connector portion. The seal member includes a first sealing portion that contacts the connector portion and a second sealing portion that contacts the inner edge of the through-hole, creating a barrier that prevents moisture from entering through the through-hole while still allowing the connector to pass through and connect to the external terminal.
2Object-affected harmful factors
If the seal is placed directly at the through-hole opening, then moisture intrusion is prevented, but water droplets may accumulate on the seal causing deterioration
Solution Approach 1:
A groove portion is formed on the obverse surface of the cover, extending from the through-hole in a direction away from the housing. This creates a new dimensional feature (the groove) that provides a drainage path for water droplets, allowing them to be guided away from the seal member and preventing accumulation that would lead to seal deterioration.
Data Source
AI summary
A motor assembly includes a motor, a controller, a housing, and a seal. The housing includes a cover that covers the controller from one side in the axial direction. The cover includes a through-hole penetrating in the axial direction. The controller includes a connector portion extending through the through-hole and protruding to one side in the axial direction of the cover. The seal seals an area between an inner edge of the through-hole and the connector portion. An obverse surface on one side in the axial direction of the cover includes a groove portion recessed to the other side in the axial direction. One end of the groove portion communicates with the through-hole.