Capacitive Water Sensor Assembly for Fuel Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional water-in-fuel sensors rely on dissolved solids to detect water, which can lead to inaccuracies and are prone to corrosion and wear due to direct contact with the fluid.
Innovation Solution
A capacitive sensor assembly with a probe generating an electromagnetic field, using a voltage source to determine water presence based on changes in output voltage and current, eliminating the need for direct contact and additional power lines, and incorporating a housing for electrical insulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional sensors rely on dissolved solids to detect water, then water detection can be achieved, but measurement accuracy deteriorates and the sensor becomes prone to corrosion and wear
Solution Approach 1:
The patent replaces the conventional mechanical/electrical contact-based sensing mechanism with a capacitive sensing mechanism. The capacitive sensor detects water presence through changes in capacitance caused by the dielectric properties of water, eliminating the need for direct contact between sensor elements and the fluid. This substitution resolves the contradiction by providing both high reliability (no corrosion or wear from contact) and high measurement precision (accurate detection based on dielectric constant differences).
Solution Approach 2:
The patent introduces the dielectric property of water as an intermediary for detection. Instead of directly sensing water through contact, the sensor detects changes in the electrical field caused by water's high dielectric constant. This intermediary approach allows accurate water detection without direct sensor-fluid contact, simultaneously improving both reliability and measurement precision.
2Measurement precision
If a capacitive sensor uses a voltage source to detect water presence, then measurement precision improves, but device complexity increases
Solution Approach 1:
The patent makes the signal line serve multiple functions: it provides power to the capacitive sensor, carries the sensing signal, and acts as one of the capacitor plates. This multi-functionality reduces device complexity by eliminating separate power lines and simplifying the overall sensor structure while maintaining high measurement precision through capacitive detection.
Solution Approach 2:
The patent merges the power supply function and sensing function into a single integrated capacitive sensing mechanism. The voltage source serves both to power the sensor and to create the electrical field for detection, while the signal line serves as both a conductor and a sensor element. This merging reduces component count and simplifies the device structure.
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 provides accurate and durable water detection in fuels, avoiding corrosion and improving reliability by directly sensing water without relying on dissolved solids, thus offering enhanced accuracy and longevity compared to conventional sensors.
Implementation Method 1
The sensor body may include a capacitive sensor generating an electromagnetic field
Implementation Method 2
detect or sense the presence of water in a fuel or other fluid, such as a nonsoluble fluid with a low dielectric constant
Data Source
AI summary
A sensor assembly and method of sensing water in a fluid may include a sensor body having a first electrical connection, a second electrical connection, and a probe portion configured to be submerged in a fluid comprising a fuel, a signal input line supplying a signal voltage and power to the sensor from a voltage source to the first electrical connection of the sensor body, a ground line connected to the second electrical connection of the sensor body, and a controller configured to receive a signal output from the signal input line for determining a presence of water in the fluid.