Fan Shroud Hinge With Dual-Position Locking Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional fan shroud assembly processes face issues with high friction in hinge mechanisms, leading to breakage and increased assembly efforts due to the need for strong retention during shipping and handling, which complicates the movement of a movable segment into position around the cooling fan.
Innovation Solution
A cooling fan shroud with a dual-position locking mechanism and hinge system using a pivot plate and base plate with a loading rib for controlled friction, combined with a ratchet pocket and tab mechanism for secure positioning, allowing easy extension and robust retention of a movable cylindrical segment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a molded pin or clip hinge is used to secure the movable segment during shipping, then the segment is retained securely, but the friction increases assembly difficulty and the clips are subject to breakage
Solution Approach 1:
The hinge mechanism uses a loading rib that provides friction only at specific locations (the interface between the pin and the clip arms) rather than along the entire hinge interface. This localized friction application secures the movable segment during shipping while allowing controlled movement during assembly when the tab engages the ratchet pocket.
Solution Approach 2:
The hinge transitions from a static high-friction connection to a dynamic controlled-movement system. The spring arms can compress to allow movement, and the tab-ratchet mechanism enables transition between locked and unlocked states, making the retention force dynamic rather than constant.
2Reliability
If high friction is used in the hinge to prevent movement during shipping, then the movable segment is securely retained, but the assembly process becomes more difficult
Solution Approach 1:
The hinge is divided into distinct functional components: the pin provides the friction interface, the spring arms provide compliance and retention force, and the tab-ratchet mechanism provides controlled locking. This segmentation allows each component to be optimized for its specific function while working together to reduce overall complexity.
Solution Approach 2:
The loading rib acts as an intermediary element between the pin and the clip arms, providing the necessary friction interface without requiring complex surfaces or mechanisms. The tab serves as an intermediary between the movable segment and the ratchet pocket, enabling controlled engagement and disengagement.
3Device complexity
If a conventional molded pin hinge is used, then the hinge structure is simple, but the clips are subject to breakage at high rates
Solution Approach 1:
The hinge design changes the stress distribution parameters by using spring arms that can compress and flex, rather than rigid molded clips. This allows the material to deform elastically under load, reducing stress concentration points that would lead to breakage while maintaining structural integrity.
Solution Approach 2:
The spring arms are designed to compress beforehand to absorb and distribute applied forces, cushioning against sudden impacts or excessive loads that would cause clip breakage. This preemptive cushioning protects the hinge components from damage during assembly and operation.
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 solution provides a robust and reliable swivel interface with reduced vibrations, easier assembly, and customizable ergonomic performance, ensuring the movable segment remains securely in place during shipping and operation without excessive wear or breakage.
Implementation Method 1
One of the plates includes a loading rib to provide a predetermined frictional resistance
Data Source
AI summary
A cooling fan shroud for an internal combustion engine has a fan port including a fixed cylindrical segment and a movable cylindrical segment mounted by a hinge. A pivot plate on the movable cylindrical segment is compressed with a base plate on a shroud main body so that a loading rib on one plate provides a frictional resistance. A dual-position locking mechanism retains the movable cylindrical segment in an extended position or a retracted position. The mechanism is comprised of a tab extending from the movable cylindrical segment and a ratchet pocket in the main body receiving the tab, wherein the ratchet pocket has a pair of stop notches separated by a deflector rib. The movable cylindrical segment is bendable to allow the tab to ride over the deflector rib in response to a predetermined pivot force applied to the movable cylindrical segment.