Vehicle Electrical Connection Box Waterproofing Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrical connection boxes in vehicles are prone to water ingress when exposed to high-pressure washes, as water can enter the space between the inner and outer walls of the housing, compromising their waterproofness.
Innovation Solution
The design incorporates a first housing member with double walls and a second housing member featuring a bulge that protrudes towards the first outer wall, creating an interior space that communicates with the outside through an opening, and includes reinforcing ribs to enhance waterproofing. This configuration changes the orientation of the gap between the inner and outer walls from upward to horizontal, preventing water from entering and using reinforcing ribs to prevent the outer wall from collapsing inward under pressure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional double-wall structure is used with the lower cover fitted to the frame, then the housing members can be assembled together, but water can enter the space between the inner wall and outer wall from the interface between the housing body and the lower cover when exposed to high-pressure washes
Solution Approach 1:
The patent inverts the conventional design by making the inner wall (first inner wall) protrude outward beyond the outer wall (second outer wall) at the lower end. This reversal of the expected configuration creates an overlapping structure where the inner wall covers the outer wall, preventing water from entering the gap between walls while maintaining the double-wall protective structure
Solution Approach 2:
The patent adds a vertical dimension to the waterproofing solution by creating an overlapping configuration where the first inner wall extends downward below the level of the second outer wall. This dimensional change transforms the horizontal gap prevention into a vertical overlap arrangement, effectively blocking water ingress paths that would exist in conventional flush or inward-protruding designs
2Reliability
If the gap between inner and outer walls is oriented upward to drain water, then water can discharge externally, but the outer wall may collapse inward under high-pressure water impact
Solution Approach 1:
The patent applies preliminary anti-action by providing reinforcing ribs on the inner surface of the second outer wall before water pressure can cause collapse. These ribs are pre-positioned to counteract the inward force of high-pressure water, preventing deformation of the outer wall while maintaining the upward-oriented gap for water discharge
Solution Approach 2:
The patent applies local quality by adding reinforcing ribs only at specific locations on the second outer wall where water pressure would cause collapse, rather than uniformly thickening the entire wall. The ribs are strategically positioned to provide localized structural support while maintaining the overall lightweight and water-discharge-friendly design
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An electrical connection box (1) includes: a frame (3) accommodating electronic components (100); and a lower cover (5) located below the frame (3) and closing a lower opening (3b). The frame (3) includes double walls including a first outer wall (31) and a first inner wall (32) and formed along the lower opening (3b). The lower cover (5) includes: a second outer wall (51) located between the first outer wall (31) and the first inner wall (32) in a placement state; and a second inner wall (52) formed inside the second outer wall (51) and along the second outer wall (51). The first inner wall (32) includes: a body (32A) formed in such a manner that a lower end (32a) is located between the second outer wall (51) and the second inner wall (52) in the placement state; and a bulge (32B) protruding toward the first outer wall (31) from an opposed surface (31Aa), being opposite to the first outer wall (31), of the body (32A).