Karman's vortex flow meter
US4970902A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Dec 4, 1989 |
| Grant date | Nov 20, 1990 |
| Priority date | — |
| Expiry date | Dec 4, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01F1/662
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A Karman vortex flow meter comprises a vortex generating post 4 disposed in a fluid conduit 1, a plurality of ultrasonic wave transmitters 6a, 6b provided in a wall of the conduit downstream of the post, and an ultrasonic wave receiver 8 provided in a wall of the conduit opposing the transmitters. The transmitters are either juxtaposed at a horizontal sectional face of the conduit and generated ultrasonic waves simultaneously toward the receiver, or they are provided in series in an axial direction of the conduit while the receiver is provided opposite the transmitter on the downstream side. In the latter embodiment the transmitters are connected to a change-over circuit which switches from the downstream transmitter to the upstream one when the detected frequency of the Karman vortex streets in the fluid exceeds a predetermined value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.