Process for controlling the flow of a fluid in a valve and apparatus for carrying out said process
US4763681A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 1987 |
| Grant date | Aug 16, 1988 |
| Priority date | — |
| Expiry date | Feb 12, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/7761
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Process for controlling the flow of a fluid through a valve having a given section and a movable valve member, in which the pressures of the fluid which are upstream P.sub.upstream and downstream P.sub.downstream of the valve and the position d of the valve member are measured, then the real flow Q.sub.real of the fluid is calculated and compared with a set value Q.sub.0, the difference signal Q.sub.real -Q.sub.0 commanding the displacement of the valve member in the desired direction, said process comprising effecting the real flow calculation by measuring the ratio R=P.sub.upstream /P.sub.downstream which is compared with a predetermined value R and calculating the product Q.sub.sonic =k.times.P.sub.upstream .times.d so that when R>R.sub.0, the product Q.sub.sonic is directly compared with a set value Q.sub.0, the difference signal Q.sub.sonic -Q.sub.0 commanding the displacement of the valve member in the desired direction whereas, when R<R.sub.0, the ratio R is converted into a digital signal whose value corresponds to the address of a memory whose content is converted into an analog correction signal which, after multiplication by Q.sub.sonic, represents a value proportional t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.