Propeller-Shaped Cable Grommet for Low-Force Harness Insertion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production process for applying bulkhead grommets in vehicles is complex, time-consuming, and requires significant operator effort, making it difficult to efficiently receive and guide electric cables and harnesses with connectors.
Innovation Solution
A grommet with a sleeve body made of flexible material, featuring a propeller-shaped opening that unfolds to increase the cross-sectional area, allowing for easier insertion of cables and harnesses without stretching the material, and providing a flexible and sealing engagement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of moving object
If a standard circular opening grommet is used, then the material structure is simple, but the clearance is insufficient for large diameter cables and requires significant stretching force
Solution Approach 1:
The grommet opening transitions from a static circular shape to a dynamic propeller shape that can unfold during cable insertion. The propeller blades are designed to flex outward when force is applied, progressively increasing the opening area to accommodate large diameter cables without requiring excessive insertion force
Solution Approach 2:
The opening geometry transitions from a two-dimensional circular cross-section to a three-dimensional propeller configuration with radial blades. This dimensional change allows the opening to expand in multiple directions simultaneously, significantly increasing the effective clearance area while distributing the insertion force across a larger structural framework
2Area of moving object
If the grommet opening is enlarged to accommodate large diameter cables, then the clearance increases, but the material must be stretched significantly which risks damage
Solution Approach 1:
The propeller-shaped blades are designed with controlled flexibility, allowing them to unfold dynamically during cable insertion rather than requiring static stretching of the entire grommet material. This dynamic unfolding mechanism increases cross-sectional area while keeping material stress within safe limits
Solution Approach 2:
The grommet opening is segmented into multiple propeller blades rather than being a single continuous circular wall. This segmentation allows each blade to move and unfold independently, distributing the structural stress and enabling area expansion without compromising overall material integrity
3Productivity
If traditional grommet installation methods are used, then the process is simple, but it is time-consuming and requires significant operator effort
Solution Approach 1:
The propeller-shaped opening provides self-guiding characteristics during cable insertion. The unfolded propeller blades naturally guide the cable into the correct position and orientation, reducing the need for operator manipulation and alignment adjustments while speeding up the installation process
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The propeller-shaped grommet design allows for a significant increase in clearance without material stretching, facilitating the assembly of cables and harnesses with larger diameters, reducing operator effort, and enabling potential automation of the harness assembly process.
Implementation Method 1
The grommet comprises a sleeve body of a flexible material having two opposed openings, where at least one of the openings in unloaded condition has a cross sectional shape, as seen in axial insertion direction, of a propeller
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A grommet 1 for receiving cables, such as a harness for a vehicle, the grommet 1 comprising a sleeve body 2 of a flexible material having two opposed openings 4; 6, characterized in that the first opening 4 in unloaded condition has a cross sectional shape, as seen in axial insertion direction, of a propeller.