Patent ID: 7329390
Filing Date: 2008-02-12
Classification: A61B,G01N,Y10S,Y10T

Abstract:
1. A device for measuring breath alcohol, the device comprising: a flow chamber receiving exhaled breathing gas flow of a test subject; a flow diaphragm arranged in said flow chamber for flow through said flow diaphragm from an upstream side of said flow diaphragm to a downstream side of said flow diaphragm; a first gas line in communication with an interior space of said flow chamber upstream of said flow diaphragm; a breath alcohol sensor in communication with an interior space of said flow chamber downstream of said flow diaphragm; a second gas line in communication with said breath alcohol sensor; a differential pressure sensor bridging over said flow diaphragm, a first measuring connection of said differential pressure sensor being connected to said first gas line, a second measuring connection of said differential pressure sensor being connected through said second gas line and said breath alcohol sensor to said interior space of said flow chamber downstream of said flow diaphragm; a throttling element arranged in said second gas line; a sampling system connected to said second gas line, said sampling system generating suction for pulling a gas sample into said breath alcohol sensor and toward or into said second gas line; and an evaluating and control unit connected on an input side to said pressure and alcohol sensors and receiving measured signals of said sensors, said evaluating and control unit being connected on an output side to said sampling system for controlling said sampling system.