Torque-Sensing Threaded Fastener Neck Structure Without Cavities
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing threaded fasteners for torque detection suffer from asymmetric structural design leading to inaccuracy, costly manufacturing due to required cavities, and exposure of sensing elements to damage, compromising both measurement precision and structural strength.
Innovation Solution
A threaded fastener design featuring a neck with a non-threaded peripheral surface at the junction of the shank and head, equipped with sensing elements protected by a sealing element and covered by a covering element, eliminating the need for cavities and enhancing structural symmetry and manufacturing ease.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a cavity is provided at the junction between the threaded shank and the head to mount the strain gage, then torque detection capability is achieved, but the structural design becomes asymmetric leading to measurement inaccuracy
Solution Approach 1:
The invention extracts the strain gage mounting function from a cavity structure and relocates it to the outer surface of the head. This eliminates the asymmetric cavity while preserving the torque detection capability through surface-mounted strain gages that measure deformation without disrupting the fastener's symmetric structural integrity.
Solution Approach 2:
The invention transitions from three-dimensional cavity embedding to two-dimensional surface mounting. By placing strain gages on the outer surface of the head rather than embedding them in a cavity, the solution maintains structural symmetry while achieving the same torque detection function through a different spatial arrangement.
2Reliability
If a cavity is formed at the junction between the threaded shank and the head, then the strain gage can be mounted, but manufacturing complexity and cost increase
Solution Approach 1:
The invention removes the complex cavity formation step from the manufacturing process by extracting the strain gage mounting function to the head's outer surface. This eliminates the need for difficult machining operations at the shank-head junction, significantly simplifying manufacturing while preserving torque detection functionality.
Solution Approach 2:
Instead of embedding the strain gage into the fastener body through cavity formation, the invention inverts the approach by mounting the strain gage on the external surface of the head. This reversal of the mounting methodology transforms a complex internal machining operation into a simple external attachment process.
3Reliability
If a cavity is formed at the junction between the threaded shank and the head, then the strain gage can be installed, but structural strength is compromised
Solution Approach 1:
The invention extracts the strain gage mounting location from the critical shank-head junction area and relocates it to the head's outer surface. This removes the structural weakness caused by cavity formation while maintaining the ability to detect torque through strategically positioned strain gages that measure deformation without compromising structural integrity.
4Measurement precision
If the strain gage is exposed without protection, then it can detect deformation, but it is vulnerable to damage from collision
Solution Approach 1:
The invention applies beforehand cushioning by providing a protective coating or cover over the strain gage mounted on the head surface. This protective layer shields the fragile sensing element from mechanical damage, collision, and environmental factors while allowing it to continue detecting deformation for torque measurement throughout the fastener's service life.
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
This design enables accurate torque detection with improved structural strength, reduced manufacturing complexity, and enhanced protection of sensing elements, leading to precise and durable torque measurement capabilities.
Implementation Method 1
The sensing element is provided on the neck to detect deformation of the neck
Data Source
AI summary
A threaded fastener capable of torque detection includes: a head and a shank connected together, wherein the shank has a threaded peripheral surface; a neck formed at the junction between one end of the shank and the head; and at least one sensing element and a sealing element, both provided on the neck, wherein the sensing element is configured to detect deformation of the neck, and the sealing element seals the sensing element. The threaded fastener may further include a covering element that covers the sealing element. The threaded fastener can be deformed consistently, allowing the sensing element to obtain relatively accurate detection values.