Spring-Tensioned Fastener for Tool-Free Vibration Locking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional nut-and-bolt fasteners require rotational force for assembly, are prone to loosening due to vibration, and necessitate multiple tools and sizes, making them cumbersome and unreliable, especially in spatially constrained environments like outer space.
Innovation Solution
A fastener system with a bolt and nut featuring integrally formed deflectable spring tensioners that allow unidirectional movement, eliminating the need for rotational force and preventing loosening through frictional engagement and deflection mechanisms.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If rotational force is applied to tighten the nut and bolt, then the fastener can be secured, but it requires tools and time, and may not be possible in spatially constrained environments
Solution Approach 1:
The fastener system uses self-locking teeth on the bolt shaft that automatically engage with corresponding features on the nut during linear movement, eliminating the need for rotational tightening tools or operations. The spring tensioner maintains constant pressure to ensure reliable engagement without requiring external torque application.
2Ease of operation
If conventional threaded fasteners are used, then they can be assembled with standard tools, but they are prone to loosening due to vibration and cyclic loading
Solution Approach 1:
The spring tensioner dynamically adjusts to maintain constant contact pressure between the bolt and nut components, allowing the fastener to self-adjust to vibration and cyclic loading conditions. The deflectable spring ensures continuous engagement of the self-locking teeth, preventing loosening without requiring secondary locking mechanisms.
3Adaptability or versatility
If multiple bolt lengths are stocked for different applications, then appropriate fasteners can be selected for each case, but it increases inventory complexity and cost
Solution Approach 1:
The fastener system is designed with modular components where the bolt length can be varied without changing the fundamental engagement mechanism. The self-locking teeth and spring tensioner configuration remains effective across different lengths, allowing a single design to serve multiple applications while reducing the need to stock multiple specialized fastener types.
4Reliability
If two tools are employed to torque the nut with respect to the bolt, then rotational control is achieved, but the process becomes more complex and time-consuming
Solution Approach 1:
The invention replaces the rotational mechanical system with a linear movement system. Instead of using two tools to apply and control rotational torque, the fastener is assembled by simply pushing the nut onto the bolt shaft, where linear movement automatically engages the self-locking teeth. This eliminates the need for torque tools and significantly reduces assembly time while maintaining secure fastening.
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
Enables easy assembly without tools, prevents loosening under vibration, and allows for secure fastening in various environments, including zero-gravity conditions, while being cost-effective and adaptable to different applications.
Implementation Method 1
The spring tensioner on the head is configured to deflect away from the longitudinal axis towards a proximal end when in deflected configuration so as to reduce the distance the spring tensioner extends beyond the undersurface of the head
Implementation Method 2
The bore and shaft are sized and configured such that the shaft is frictionally engaged within the bore and movable relative to the nut along the longitudinal axis
Data Source
AI summary
A nut-and-bolt fastener is provided. The nut and bolt are configured with a plurality of integrally formed spring tensioners. The spring tensioners are deflectable into channels to then exert a spring-bias force against workpiece members fastened between the nut and bolt. The spring-bias force increases the frictional force against mating teeth of the bolt and nut to lock the nut to the bolt and prevent disengagement of the fastener over time. The spring tensioners are employed in fasteners with helically threaded teeth providing bi-directional movement of the nut with respect to the bolt to increase preload and resist microslippage therebetween or in fasteners with non-helical, circumferential rings of teeth configured to provide unidirectional movement of the nut towards the bolt.