Diaphragm vacuum gauge with decreased parasitic capacitance
US11768120B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 2022 |
| Grant date | Sep 26, 2023 |
| Priority date | — |
| Expiry date | May 13, 2042 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L21/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An improved diaphragm vacuum gauge including a sensor chip that includes a first electrode provided on a base and a second electrode provided on a diaphragm so as to face the first electrode, the diaphragm and the base being disposed with a gap therebetween, and in which a distance between the first electrode and the second electrode changes in accordance with displacement of the diaphragm caused by pressure of a measurement target medium. The diaphragm vacuum gauge further includes an operational amplifier that converts a current output from the first electrode to a voltage and amplifies the voltage, and a coaxial cable that connects the first electrode and the operational amplifier with each other. Further, the first electrode is connected to a virtual ground of the operational amplifier by a core wire of the coaxial cable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.