Device for measuring the alcohol content of a gas
US4736619A · kind A · utility
Inventor
Key dates
| Filing date | Sep 19, 1986 |
| Grant date | Apr 12, 1988 |
| Priority date | — |
| Expiry date | Sep 19, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N33/4972
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A device for measuring the alcohol content of a gas includes an improved mechanism for determining the presence of alveolar air in the gas which is exhaled into the device by a test subject. The device has a conduit (11) into which the test subject exhales. Gas from the conduit passes through a nozzle (19) and into an intake opening (18) of a pumping device (14). Upon actuation, the pumping device extracts a first predetermined volume of exhaled air from the conduit, so that an electro-chemical cell (25) can detect the quantity of alcohol in the first predetermined volume of air. To actuate the pumping device, a predetermined value correspondig to a second volume of air must be detected by an evaluation device (28) responsive to a pressure sensitive device (27) for measuring the pressure of the gas in the conduit. In addition, the pumping device will not be actuated until a threshold circuit (35) detects a minimum pressure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.