Piezoelectric Pressure Sensor Charge Dissipation Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Piezoelectric pressure sensors used in harsh environments like internal combustion engines face issues with micro-friction and fretting corrosion, leading to increased electrical resistance and incorrect measurements due to mechanical instability and temperature effects.
Innovation Solution
A piezoelectric pressure sensor design with a membrane and piezoelectric pickup where the electrode strip is materially connected to the charge dissipation, allowing full-surface electrical contact and reducing contact resistance, and an antistrain sleeve is used to prevent mechanical stress, enabling stable charge dissipation even under strong vibrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If contact springs and tube springs are used to dissipate charges, then charge dissipation is achieved, but micro-friction and fretting corrosion occur leading to increased electrical resistance
Solution Approach 1:
The patent removes the contact springs and tube springs from the charge dissipation path. Instead, charges are dissipated directly through the housing via integrated charge dissipation elements, eliminating the mechanical contact components that caused micro-friction and fretting corrosion. This extraction of problematic components directly resolves the contradiction by eliminating the source of resistance increase while maintaining charge dissipation functionality.
Solution Approach 2:
The housing serves as an intermediary element for charge dissipation. Rather than using springs as mediators between the piezoelectric pickup and the external circuit, the housing itself becomes the charge dissipation path, providing a stable, vibration-resistant conduit for charge flow that does not suffer from contact degradation.
2Stability of the object's composition
If base metals are used in contact surfaces, then mechanical stability is achieved, but diffusion and oxide layer formation occur at high temperatures
Solution Approach 1:
The patent employs composite material structures in the charge dissipation elements, combining materials with complementary properties. The housing and charge dissipation components use material compositions that resist both mechanical degradation and high-temperature oxidation, creating a composite solution that simultaneously addresses mechanical stability and oxidation resistance without relying on base metal contact surfaces.
3Reliability
If complex spring mechanisms are used for charge dissipation, then charge dissipation is achieved, but device complexity increases
Solution Approach 1:
The patent merges the charge dissipation function directly into the housing structure. The housing simultaneously serves as mechanical protection, structural support, and charge dissipation pathway, eliminating the need for separate spring mechanisms. This consolidation reduces device complexity while maintaining reliable charge dissipation through the integrated electrical connection to the external circuit.
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 ensures uncorrupted charge dissipation and mechanical stability, preventing falsification of measurements and allowing for cost-effective production by maintaining electrical contact and reducing the risk of increased resistance.
Implementation Method 1
Piezoelectric crystal material is often used to manufacture a piezoelectric pickup. The piezoelectric crystal material is crystallographically cut in such a way that it has a high sensitivity to a force to be absorbed. Under the action of the force, electric polarization charges are generated on surfaces of the piezoelectric crystal material.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a piezoelectric pressure sensor (1) with a membrane (21) that detects a force; with a piezoelectric sensor (22) on which the detected force generates electrical polarization charges; with an electrode (25) that receives the generated electrical polarization charges and dissipates them via a charge conductor (311); wherein the electrode (25) has a charge tap (251) and at least one electrode strip (252); wherein the charge tap (251) is arranged parallel to an end face (2231) of the piezoelectric sensor (22) on which end face (2231) the force acts; and wherein the electrode strip (252) is partially metallurgically bonded to the charge conductor (311).