Silicone Resin Sensor Housing for Void-Free High-Temperature Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sensors face challenges in providing reliable, reproducible measurements while being sustainable and less polluting, due to the use of ecologically questionable materials that lead to inhomogeneous surroundings and thermomechanical stress, leading to fluctuating responses and potential failure.
Innovation Solution
A sensor design using a silicone resin to encapsulate and fix the sensor element and electrical leads within a housing, eliminating voids and bubbles, and employing a lead-free solder to ensure reliable connections and operation up to higher temperatures, with a metal oxide or ceramic housing for stability and insulation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If alumina oxide or silicon oxide filling materials are used, then the housing can be processed, but voids, vesicles and bubbles occur leading to inhomogeneous surrounding and fluctuating measurements
Solution Approach 1:
The patent changes the fundamental parameter of the filling material from inorganic particles (alumina oxide, silicon oxide) to organic polymer (silicone resin). This material parameter change eliminates the need for solvents during processing, preventing void and bubble formation while maintaining manufacturability, thereby resolving the contradiction between ease of manufacture and measurement precision.
Solution Approach 2:
The patent uses silicone resin as a composite filling material that combines the benefits of processability (like inorganic materials) with the advantage of forming homogeneous, void-free structures. The silicone resin creates a uniform composite structure around the sensor element, ensuring consistent thermal contact and reliable measurements.
2Ease of manufacture
If conventional filling materials are used, then the sensor can be assembled, but thermomechanical stress is induced on the sensor element during temperature changes
Solution Approach 1:
The patent changes the thermal expansion parameter of the filling material by using silicone resin, which has a thermal expansion coefficient better matched to the sensor element and housing materials. This parameter change reduces thermomechanical stress during temperature cycling, preventing connection disengagement and element breakage while maintaining assembly capability.
3Ease of manufacture
If epoxy resin is used as filling material, then the sensor can be filled and fixed, but the resin degrades at temperatures above 150°C
Solution Approach 1:
The patent changes the thermal stability parameter of the filling material by selecting silicone resin instead of epoxy resin. Silicone resin maintains its structural integrity and functional properties at temperatures up to 200°C and beyond, whereas epoxy resin degrades above 150°C. This parameter change enables the sensor to operate reliably in high-temperature environments while maintaining the filling and fixing functionality.
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 design enhances measurement reliability, reduces thermomechanical stress, allows for higher temperature operation, and is environmentally friendly, ensuring precise and reproducible measurements under harsh conditions.
Implementation Method 1
The housing is filled with a silicone resin and the sensor element and the electrical leads are fixed in the housing by the silicone resin
Implementation Method 2
Polymeric resins provide a homogenous heat transfer from the environment to the sensor element resulting in a fast thermal response
Implementation Method 3
In applications in which the sensor has to endure temperature rises a filling resin will expand due to the thermal expansion coefficient
Implementation Method 4
employing a lead-free solder to ensure reliable connections and operation up to higher temperatures
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
A sensor (1) is provided which comprises a sensor element (2) and electrical leads (3), whereby the sensor element (2) is connected to the electrical leads (3). Further, a housing (4) is provided, whereby the housing (4) has an opening and the sensor element (2) is arranged in the housing (4) such that the electrical leads (3) protrude through the opening. The housing (4) is filled with silicone resin (5) and the sensor element (2) and the electrical leads (3) are fixed in the housing by silicone resin (5).