Ultrasonic Sensor Self-Alignment Thrust Bearing Fastener Tension
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Previous sensor arrangements for measuring ultra sonic sound wave travel times in threaded fasteners face challenges due to misalignment between the sensor and the fastener end surface, leading to signal distortions and unreliable tension calculations.
Innovation Solution
A sensor unit with a movable sensor element and a support member, featuring a spherical thrust bearing for self-alignment and a resilient contact surface, ensures proper contact and alignment with the fastener end surface, minimizing misalignment and signal distortions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a fixed sensor arrangement is used, then the device structure is simple, but misalignment with the fastener end surface occurs leading to signal distortion
Solution Approach 1:
The sensor element is made movable relative to the support member through a thrust bearing, allowing dynamic adjustment of the sensor's angular position. This enables the sensor to self-align with the fastener end surface during operation, transforming a static fixed arrangement into a dynamic adaptive one that maintains reliable contact without requiring complex adjustment mechanisms.
Solution Approach 2:
The sensor element automatically aligns itself with the fastener end surface through the movable support structure and thrust bearing mechanism. The system performs self-alignment without external intervention or complex control systems, using the physical interaction between the sensor, movable support, and fastener surface to achieve proper positioning independently.
2Manufacturing precision
If the sensor is made movable for self-alignment, then alignment accuracy is improved, but the device complexity increases
Solution Approach 1:
The sensor element is made movable relative to the support member through a thrust bearing, allowing dynamic adjustment of the sensor's angular position. This enables the sensor to self-align with the fastener end surface during operation, transforming a static fixed arrangement into a dynamic adaptive one that maintains reliable contact without requiring complex adjustment mechanisms.
Solution Approach 2:
A spherical thrust bearing is used to enable the sensor element to tilt and align with the fastener end surface. The spherical geometry allows for angular adjustment in multiple directions, facilitating precise self-alignment through curved surface contact rather than rigid flat mounting.
3Measurement precision
If perfect alignment is achieved, then signal distortion is eliminated, but the ease of operation decreases due to precise positioning requirements
Solution Approach 1:
The sensor element automatically aligns itself with the fastener end surface through the movable support structure and thrust bearing mechanism. The system performs self-alignment without external intervention or complex control systems, using the physical interaction between the sensor, movable support, and fastener surface to achieve proper positioning independently.
Solution Approach 2:
The sensor element is made movable relative to the support member through a thrust bearing, allowing dynamic adjustment of the sensor's angular position. This enables the sensor to self-align with the fastener end surface during operation, transforming a static fixed arrangement into a dynamic adaptive one that maintains reliable contact without requiring complex adjustment mechanisms.
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 enables accurate and distortion-free transfer of sound waves, resulting in reliable calculations of tension in threaded fasteners by ensuring consistent and even contact pressure and alignment during sound wave induction and echo detection.
Implementation Method 1
sensor elements for this purpose are of a piezo electric type and arranged to generate and induce ultra sonic sound waves into a threaded fastener element
Implementation Method 2
The thrust bearing 22 is arranged to compensate for occurring uneven contact pressure between the contact surface 14 of the sensor element 11 and the end surface of a fastener so as to have the axial force F applied to the sensor element 11 via the spring 16 distributed evenly over the contact surface 14
Implementation Method 3
A further measure taken to ensure a distortion free signal transfer between the sensor element 11 and the end surface of a threaded fastener is the provision of a thin layer of a resinous resilient material on the contact surface 14 of the sensor element 11
Data Source
AI summary
A sensor unit for inducing and indicating ultra sonic sound waves in at least one threaded fastener by physical contact with an end surface thereof, wherein the sensor unit includes: a support casing, a sensor element with forward contact surface for engaging the fastener end surface and movable relative to the support casing between rest and active positions, and a bias spring between the support casing and the sensor element to urge the sensor element into the rest position as the sensor element is out of contact with the fastener end surface and to bias the contact surface of the sensor element into physical contact with the fastener end surface in the active position. The support casing includes a positioning socket, engaged by the sensor element in the rest position, having a non-cylindrical and non-circular cross sectional inner shape and congruent with an outer shape of the sensor element.