Pin Latch Intermediate Position Misalignment Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Pin latches on aerospace vehicles often interfere with keepers due to misalignment or non-ready conditions, failing to latch properly and requiring manual intervention to correct the issue.
Innovation Solution
A pin latch design featuring a guide block, handle, shear pin, and catch-pin mechanism with automatic return and detection capabilities, allowing the latch to detect misalignment and prevent interference by automatically moving to an intermediate position when a keeper is not aligned, thus preventing the shear pin from extracting further and signaling an unlatching condition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the pin latch is designed with a simple two-position mechanism (closed and open), then the device complexity is reduced, but the reliability of latching is compromised due to potential misalignment interference
Solution Approach 1:
The latch mechanism is divided into three distinct positions: closed position, intermediate position, and open position. The shear pin is segmented into multiple sections with different properties - a resilient section that allows bending and a rigid section that provides structural support. This segmentation enables the latch to detect misalignment conditions and automatically return to the intermediate position without requiring complex external detection systems.
Solution Approach 2:
The resilient section of the shear pin is pre-configured with a predetermined bend radius that corresponds to the misalignment detection threshold. Before actual latching occurs, the system is prepared to detect misalignment conditions through the pre-bent configuration of the shear pin, allowing automatic prevention of interference with the keeper.
2Strength
If the shear pin is made rigid to ensure structural strength, then the strength is improved, but the ability to detect misalignment and automatically return is lost
Solution Approach 1:
The shear pin exhibits different mechanical properties at different locations along its length. The resilient section is designed with lower stiffness to allow bending and detection of misalignment conditions, while the rigid section maintains high strength for structural support. This local differentiation of material properties enables the shear pin to simultaneously provide both detection capability and structural integrity.
3Productivity
If manual intervention is required to correct misalignment conditions, then the device complexity remains simple, but the loss of time increases due to manual correction requirements
Solution Approach 1:
The latch mechanism is designed to automatically detect and correct misalignment conditions without requiring manual intervention. When the shear pin encounters a misaligned keeper, the resilient section bends, causing the latch to automatically return to the intermediate position. This self-correcting mechanism eliminates the need for operators to manually diagnose and correct alignment issues, significantly reducing correction time and improving operational productivity.
Data Source
AI summary
A pin latch includes a guide block, a handle having a trigger, and a shear pin housed slidably within the guide block and connected to the handle. The shear pin includes a catch-pin engageable by the trigger, and is slidable between an engageable position and a disengageable position when the handle is moved from a closed position to an open position. Alternately, the pin latch includes a bracket connected to the shear pin and includes a catch-pin, and the handle is moveable to an intermediate position, such that a trigger is disengaged from the catch-pin and the shear pin engages a stop pin. A guide block spring acts on the stop pin to retain releasably the handle in its intermediate position. The guide block includes a finger and the shear pin includes a groove sized and shaped to receive the finger when the pin latch is in an unlatchable position.