Automotive Wire Harness Lead-out Portion Scratching Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing electrical connection boxes in automobiles are prone to scratching the wire harness when the lower cover is assembled due to the strong rubbing between the inner peripheral surface of the lead-out portion and the outer surface of the wire harness.
Innovation Solution
The design includes a lead-out portion with harness contact portions on the inner peripheral surface that extend along the fitting direction and are spaced in the circumferential direction, reducing the contact area and incorporating recessed portions and a cut portion for drainage, along with a tape-winding portion for improved workability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the lower cover is moved upward to assemble the housing, then the lower cover is fitted to the frame, but the inner peripheral surface of the lead-out portion strongly rubs the outer surface of the wire harness causing scratching
Solution Approach 1:
The inner peripheral surface of the lead-out portion is segmented into multiple harness contact portions that are spaced apart in the circumferential direction. This segmentation reduces the continuous contact area between the lead-out portion and the wire harness, thereby minimizing rubbing and preventing scratching during assembly.
Solution Approach 2:
The harness contact portions are specifically positioned at locations where contact with the wire harness is necessary for structural support, while other areas of the inner peripheral surface are left non-contacting. This local quality approach ensures that contact occurs only where needed, reducing overall friction and scratching risk.
2Object-affected harmful factors
If the contact area between the lead-out portion and wire harness is reduced to prevent scratching, then the wire harness is protected from damage, but the structural support and guidance function may be compromised
Solution Approach 1:
Multiple discrete harness contact portions are distributed around the circumferential direction of the lead-out portion. This segmentation provides multiple discrete support points that collectively ensure stable positioning and guidance of the wire harness while maintaining reduced overall contact area for scratching prevention.
Solution Approach 2:
The harness contact portions work together in combination to provide both support and guidance functions. By merging the functions of multiple spaced contact points, the system achieves reliable wire harness positioning while maintaining the benefit of reduced continuous contact.
Data Source
AI summary
An electrical connection box includes a housing including a frame and a lower cover configured to be fitted to the frame in a fitting direction. At least part of the frame and at least part of the lower cover form a tubular lead-out portion. An axial direction of the lead-out portion extends along the fitting direction, and the lead-out portion allows a wire harness to be pulled out through the lead out portion, the wire harness including an end portion that is to be disposed in an inside of the housing. The lead-out portion includes harness contact portions formed on an inner peripheral surface of the lead-out portion and configured to contact the wire harness. The harness contact portions extend along the fitting direction and are spaced from one another in a circumferential direction of the lead-out portion.