Pressure type flow rate control apparatus
US5791369A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 5, 1997 |
| Grant date | Aug 11, 1998 |
| Priority date | — |
| Expiry date | Mar 5, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/87917
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A pressure type flow rate control apparatus (1) for controlling flow rate of a fluid maintains an upstream side pressure P1 of an orifice at more than about twice a downstream side pressure P2. In addition to an orifice-forming member (5) the apparatus includes a control valve (2) provided at the upstream side of the orifice, a pressure detector (3) provided between the control valve and the orifice, and an operation control device (6) for calculating a flow rate Qc from the detected pressure P1 of the pressure detector as Qc=KP1 (K being a constant) and issuing a difference as a control signal Qy between a flow rate command signal Qs and the calculated flow rate Qc to a drive unit of the control valve. The orifice upstream side pressure P1 is adjusted by opening and closing the control valve, thereby controlling the orifice downstream side flow rate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.