System for automatically shifting a measuring range of surface area measuring device
US5311783A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 13, 1992 |
| Grant date | May 17, 1994 |
| Priority date | — |
| Expiry date | Jul 13, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N15/0893
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention is directed to a system for automatically shifting a measuring range equipped in a surface area measuring device. The system for automatically shifting the measuring range is provided with an output value determining circuit receives a signal for detecting a flow rate of supply gases to be outputted from means for measuring a flow rate of supply gases for detecting an amount of the supply gases to be supplied to a sample cell and a signal for detecting a flow rate of discharge gases of the discharge gases to be outputted from means for measuring a flow rate of the discharge gases for detecting an amount of the discharge gases to be discharged from the sample cell, generates a signal for shifting the gain of an amplifier to a low level during a period for desorption of the gases when a differential signal to be outputted from the amplifier for amplifying the difference between the signal for detecting the flow rate of the supply gases and the signal for detecting the flow rate of the discharge gases, and generates a shift signal for shifting the gain of the amplifier to a high level during a period for desorption when the differential signal to be outputted fro…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.