Liquid presence and identification sensor
US5507178A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 9, 1994 |
| Grant date | Apr 16, 1996 |
| Priority date | — |
| Expiry date | Nov 9, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2291/102
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A sensor for determining both the presence of a liquid in a container or conduit, and identifying its type has a sensor housing body containing both a pair of piezoelectric elements used as the transmitter and receiver of ultrasonic waves directed across a gap therebetween in an ultrasonic liquid presence detecting circuit and a pair of electrodes exposed to any of such liquid in the gap used in a circuit for identifying the liquid type. The liquid identification circuit is either of the capacitance type, which produces a variable amplitude output signal depending on the type of liquid in the gap between the two electrodes, or operates to measure the difference in response time between pulses applied to each of the electrodes with one serving as a reference.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.