Snap Hook Hoop-Loaded Gate Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing snap hooks with locking gates are inefficient in resisting external loads directed to the side and top, leading to potential failure under ANSI standards requiring a minimum of 3500 pounds of side and top load, as thickening the gate results in a larger, heavier hook that is cumbersome for workers.
Innovation Solution
A hook with a J-shaped body and a locking gate mechanism featuring a cylindrical inner gate wall surface and a pivotally mounted gate lock that transitions from a shear-resistant to a hoop-stress-resistant configuration, assisted by a spring for consistent biasing and load distribution, allowing the gate to withstand higher loads without opening.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the gate is thickened to increase strength, then the load-bearing capacity is improved, but the hook becomes larger and heavier
Solution Approach 1:
The patent changes the loading parameter from shear load to hoop stress by redesigning the gate mechanism. The gate is configured to receive loads in hoop stress direction, which allows thinner gate design while maintaining or increasing strength, thereby reducing hook weight without compromising load-bearing capacity
Solution Approach 2:
The patent introduces a curved surface between the gate and gate lock that directs loads in hoop stress. This curved geometry redistributes the stress more efficiently through the gate structure, allowing for reduced material thickness while maintaining structural integrity and strength under load
2Strength
If the gate is thickened to increase strength, then the load-bearing capacity is improved, but the hook structure becomes more complex
Solution Approach 1:
By changing the loading mode from shear to hoop stress, the patent simplifies the overall hook structure. The gate can be thinner and the internal geometry can be optimized rather than simply thickened, leading to a more efficient and less complex design that meets ANSI standards
3Ease of manufacture
If conventional gate design is used, then the manufacturing is simple, but the gate cannot withstand 3500 pounds of side and top load
Solution Approach 1:
The patent changes the fundamental loading parameter from shear to hoop stress, which allows the gate to achieve 3500 pounds load capacity with a design that remains manufacturable. The curved surface geometry and pivot mounting are standard fabrication features that do not significantly complicate manufacturing processes
Solution Approach 2:
The introduction of the curved surface between the gate and gate lock creates hoop stress conditions that naturally distribute loads more effectively. This curved geometry can be manufactured using standard forming processes and does not require complex assembly, maintaining ease of manufacture while dramatically improving load capacity
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 design effectively doubles the strength of the gate by transitioning from shear to hoop-stress resistance, ensuring the hook can withstand significant side and top loads while maintaining a compact and lightweight form for ease of use.
Implementation Method 1
a spring that simultaneously biases both the gate and the gate lock towards the first gate position and the first lock position, respectively
Data Source
AI summary
A snap-hook having a locking element and a gate, where the locking element cooperates with the gate to place stresses on the gate in tension instead of shear is disclosed. The tension loads are achieved by using mating generally cylindrical surfaces on the gate and on the lock.