Accelerometer Seismic Mass Biasing for Mechanical Prestress
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing acceleration measuring devices, such as accelerometers, require additional components like base plates for mechanical prestress, increasing complexity and cost, while also limiting the mechanical prestress force due to smaller clamping areas.
Innovation Solution
The accelerometer design features a seismic mass with two mass elements and a biasing arrangement that mechanically biases the piezoelectric system elements, eliminating the need for a base plate and allowing for a larger clamping force by distributing the prestress over a larger area, thus reducing production costs and enhancing mechanical prestress.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a base plate is used to mechanically prestress the piezoelectric system, then the mechanical prestress can be achieved, but the device complexity increases and additional components are required
Solution Approach 1:
The invention extracts and eliminates the base plate component from the accelerometer assembly. The seismic mass itself is configured to provide the mechanical prestress function that previously required a separate base plate, thereby reducing device complexity while maintaining the necessary prestress force on the piezoelectric system
Solution Approach 2:
The seismic mass is given multiple functions: it serves both as the inertial sensing element and as the prestressing mechanism for the piezoelectric system. By integrating these functions into a single component, the invention eliminates the need for a separate base plate and reduces overall device complexity
2Strength
If a base plate is used for mechanical prestress, then the prestress can be applied, but the clamping area is limited resulting in reduced prestress force
Solution Approach 1:
The invention transitions from a two-dimensional clamping interface (base plate contact surface) to a three-dimensional distributed prestress mechanism where the seismic mass applies force through multiple contact points and surfaces on the piezoelectric system, effectively increasing the clamping area and resulting prestress force
3Strength
If additional components like base plate are used, then mechanical prestress can be achieved, but production costs increase
Solution Approach 1:
By extracting and removing the base plate component, the invention reduces the number of parts that need to be manufactured, assembled, and quality-checked, thereby lowering production costs while maintaining the mechanical prestress function through the integrated seismic mass design
Solution Approach 2:
The invention merges the prestressing function into the seismic mass component, reducing the total part count and simplifying the manufacturing process. This consolidation eliminates the need for separate base plate production and assembly operations, directly reducing production costs
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
This design enables a more cost-effective production of acceleration measuring devices with increased mechanical prestress force, allowing for improved accuracy and reliability in measuring accelerations without the need for additional components, and can operate within a wider temperature range.
Implementation Method 1
the seismic mass exerts a force proportional to its acceleration on the piezoelectric system, which force generates piezoelectric charges in the piezoelectric system
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to an acceleration measuring device (1) comprising a piezoelectric system (2), a seismic mass (3), and a base plate (4); during an acceleration, the seismic mass (3) applies a force, which is proportionate to the acceleration thereof, to the piezoelectric system (2), said force generates piezoelectric charges in the piezoelectric system (2), and said piezoelectric charges can be electrically picked up as acceleration signals; the piezoelectric system (2) includes two system elements (20, 20'), while the seismic mass (3) includes two mass elements (30, 30'); the preloading arrangement (4) mechanically preloads the system elements (20, 20') in relation to the mass elements (30, 30').