Ultrasonic material level measurement
US5644299A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 8, 1994 |
| Grant date | Jul 1, 1997 |
| Priority date | — |
| Expiry date | Jun 8, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S367/908
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Apparatus for indicating material level that includes a pair of ultrasonic transducers on opposed sides of a space for receiving the material at the level to be detected. A swept frequency oscillator is coupled to one of the transducers so that the transducer radiates into the material space ultrasonic energy that continuously sweeps back and forth between a low frequency range at which such energy is transmitted to the other transducer by resonance of the entire apparatus and independent of presence of material in the material space, and a higher frequency range at which such energy is transmitted to the other transducer only when material is present in the space between the transducers. Detection circuitry indicates presence of material between the transducers upon receipt of the higher frequency energy, and failure of the apparatus upon failure to receive the lower frequency energy.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.