Vehicle Power Steering Motor Frame End Water Intrusion Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electric motors used as drive sources for vehicle power steering apparatuses face challenges in preventing water intrusion due to temperature expansion and contraction, especially when installed with the rotatable shaft parallel or tilted relative to the gravitational force, leading to water accumulation and potential penetration through gaps formed by frame end flexing.
Innovation Solution
The electric motor design features a stator core with a tubular shape and frame ends that contact the stator core's outer peripheral surfaces, with a relief groove and radially inwardly recessed design to reduce water accumulation and prevent intrusion, using a fixture element to secure the frame ends and maintain structural integrity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the frame end is fitted to the outer side of the stator core to eliminate the case, then the number of components and assembling steps is reduced, but water accumulates at the corner between the frame end and stator core, leading to potential water intrusion
Solution Approach 1:
The frame end is segmented into an integrated structure that includes both the frame end body and a protruding protective portion. This segmentation creates a stepped configuration where the protective portion extends beyond the stator core outer diameter, forming a water-shedding ledge that prevents water accumulation at the corner between the frame end and stator core.
Solution Approach 2:
The protruding protective portion acts as an intermediary element between the frame end and the stator core. It serves as a water-shedding structure that intercepts water before it can reach the corner joint, thereby protecting the interface without requiring additional sealing components or cases.
2Object-affected harmful factors
If the tubular portion is provided to prevent water accumulation, then water intrusion is reduced, but the contact location is radially inwardly displaced from bolt fixation locations, causing frame end flexing and gap formation
Solution Approach 1:
The protective water-shedding function and the structural support function are merged into a single integrated frame end structure. The protruding protective portion is formed as an integral part of the frame end, eliminating the need for separate tubular portions while maintaining both water protection and structural stability through unified design.
Solution Approach 2:
The frame end structure is designed to perform multiple functions simultaneously: it provides structural support for the stator core, serves as a mounting surface for bolts, and incorporates a water-shedding protective portion. This multi-functional design eliminates the need for separate components and ensures structural integrity while preventing water accumulation.
Data Source
AI summary
A first end contact portion of a first frame end contacts one end surface of a stator core. A second end contact portion of a second frame end contacts the other end surface of the stator core and includes an inner tubular part, which contacts the other end surface of the stator core, and a fixing part, which projects radially outward from the inner tubular part and contacts the other end surface. A through-bolt is threaded into the fixing part. An outer diameter of the one end surface is smaller than an outer diameter of an opposing surface of the first end contact portion. An outer diameter of an opposing surface of the inner tubular part is smaller than an outer diameter of the other end surface. A yoke of the stator core includes a relief groove, into which a portion of the through-bolt is fitted.