Physical Quantity Sensor Equipotential Shielding Electrode
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing physical quantity sensors face reduced sensing functionality due to electrostatic forces generated between wiring and movable electrodes, inhibiting the rocking motion necessary for acceleration detection.
Innovation Solution
A physical quantity sensor design featuring a movable electrode with a peripherally arranged section of the same potential as the electrode, which surrounds the movable section to reduce electrostatic interference, allowing for accurate rocking and improved sensing functionality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If wiring with different potential is arranged at the periphery of the movable electrode section, then electrical connection is achieved, but electrostatic force is generated that inhibits rocking motion
Solution Approach 1:
The patent applies the equipotentiality principle by providing a shielding electrode that is electrically connected to the movable electrode, ensuring they share the same potential. This eliminates the potential difference between the peripheral wiring and movable electrode, thereby preventing electrostatic force generation that would inhibit rocking motion. The shielding electrode acts as an equipotential barrier, allowing the movable electrode to rock freely while maintaining proper electrical connections.
2Adaptability or versatility
If wiring is placed near the movable electrode for electrical connection, then device functionality is achieved, but sensing precision is reduced due to electrostatic interference
Solution Approach 1:
The patent introduces a shielding electrode as an intermediary element between the wiring and the movable electrode. This intermediary structure serves dual purposes: it maintains the necessary electrical connections for device functionality while simultaneously blocking the electrostatic field interaction between the wiring and movable electrode. By placing this intermediary shielding electrode in the periphery, the patent preserves sensing precision without sacrificing device adaptability.
3Ease of operation
If peripheral wiring is arranged for electrical connection, then device operation is enabled, but unintended displacement and damage occur due to electrostatic forces
Solution Approach 1:
The patent implements preliminary anti-action by pre-establishing the shielding electrode connection to the movable electrode before the device operates. This preliminary configuration ensures that when the device is in operation, the electrostatic force that would otherwise cause harmful unintended displacement and damage is already neutralized. The shielding electrode is positioned and connected in advance to counteract any potential electrostatic interference, protecting the movable electrode from damage while maintaining ease of operation.
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 the physical quantity sensing function by minimizing electrostatic forces, enabling precise detection of acceleration and reducing unintended displacement and damage.
Implementation Method 1
a movable electrode which includes a movable section that has a first movable section which is included at one side and a second movable section which is included at the other side that has a rotational moment, which is generated when acceleration is applied, that is different from the first movable section
Implementation Method 2
a fixed electrode which is included to oppose the large movable electrode section and which forms an electrostatic capacity with the large movable electrode section, and a fixed electrode which is included to oppose the small movable electrode section and which forms an electrostatic capacity with the small movable electrode section
Implementation Method 3
displacement of the movable electrode section when acceleration is applied is inhibited by electrostatic force which is generated between the wiring and the movable electrode section
Data Source
AI summary
A physical quantity sensor has a first movable section, a second movable section that has a rotational moment, which is generated when acceleration is applied, that is different from the first movable section, a movable section that is supported so as to be able to rock about an axis which is positioned between the first movable section and the second movable section, a first detection electrode which is arranged so as to oppose the first movable section, a second detection electrode which is arranged so as to oppose the second movable section, and a frame-form section which is arranged so as to surround at least a portion of the periphery of the movable section in planar view of the movable section and which has the same potential as the movable section.