Capacitive Sensor Element With Dielectric Liquid Cavity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional capacitive sensors are complex and costly to produce, with limited robustness against external influences such as impacts, temperature fluctuations, and contamination, which reduces their service life.
Innovation Solution
A capacitive sensor element is created by arranging a first substrate part with a first electrode structure and a second substrate part with a second electrode structure separated by a spacer, forming a cavity that is filled with a dielectric liquid, allowing inclination to be determined by changes in the capacitor area, with the option of using printed circuit boards or ceramic substrates and a hybrid construction for cost-effectiveness and robustness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional capacitive sensors are used with complex designs (pendulums, multiple electrode pairs, ceramic cavities), then measurement functionality is achieved, but production cost and device complexity increase significantly
Solution Approach 1:
The sensor is divided into three separate components: a base with first electrode structure, a cover with second electrode structure, and a spacer. These segments are produced independently and assembled together, simplifying manufacturing while maintaining functionality. The spacer segment specifically creates the cavity without requiring complex integrated structures.
Solution Approach 2:
The base and cover serve multiple functions: they provide structural support, hold the electrode structures, create the sealing cavity when assembled, and provide mounting surfaces for the spacer. This multi-functionality reduces the need for additional specialized components, simplifying overall construction.
2Reliability
If conventional capacitive sensors use pendulums or liquid arrangements, then inclination measurement is enabled, but robustness against external influences (impacts, temperature, contamination) deteriorates
Solution Approach 1:
The spacer acts as a sealing barrier that encloses the cavity, protecting the dielectric liquid from external contamination while allowing the electrode structures to flex slightly with temperature changes. This sealing approach protects against contamination without requiring fragile sealed cavities.
Solution Approach 2:
The invention replaces fragile mechanical pendulum systems with a rigid, sealed capacitor structure filled with dielectric liquid. The measurement is achieved through electrical capacitance changes rather than mechanical movement, eliminating sensitivity to impacts and mechanical wear.
3Measurement precision
If differential capacitance measurement is implemented, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The first electrode structure is divided into two separate parts on the base, each forming a capacitor with the second electrode structure on the cover. This segmentation enables differential measurement by comparing capacitances of two separate capacitor arrangements, improving precision while keeping individual electrode structures simple.
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 the production of capacitive sensors that are simple, inexpensive, and insensitive to external influences, improving their reliability and service life while maintaining sensitivity through differential capacitance measurements.
Implementation Method 1
the first and second electrode structures with the dielectric liquid located between them form a capacitor, the capacitor area of which changes when the sensor element is tilted
Implementation Method 2
The cavity can then be filled with a dielectric liquid, so that the first and second electrode structures with the dielectric liquid located between them form a capacitor
Data Source
Figure 1
Figure 2a~2c
Figure 3a~3b
AI summary
The invention relates to a method for the production of a capacitive sensor comprising the arrangement of a spacer (3) between a base (1) having a first electrode structure (5b) and a lid (2) having a second electrode structure (5a), such that a hollow space (4) is formed between the first electrode structure (5b) and the second electrode structure (5a), that is delimited laterally by the spacer (3). The method further comprises the formation of a liquid-tight connection between the bottom (1) and the spacer (3) and forming of a liquid-tight connection between the spacer (3) and the lid (2).