| 摘要 |
A breath sampler device for use with an air analyzer. The sampler includes a chamber, an intake port leading into the chamber, an outlet port exiting from the chamber, and a breathing port through which a subject inhales from and exhales into the chamber. An intake check valve provides for unidirectional air flow through the intake port into the chamber, and an outlet check valve provides for unidirectional air flow out of the chamber through the outlet port. An air reservoir having a sampling region is associated with the outlet port. Upon exhalation, the outlet check valve opens and the air which has just been exhaled from the subject's lungs is passed from the chamber into the air reservoir where it replaces the residual air contained in the reservoir sampling region from a previous exhalation. In order to discretely sample this expired air before it can be affected by conditions outside the subject's body, a pressure sensing membrane is provided which responds to the decrease in pressure inside the chamber on subsequent inhalation to actuate a switch which closes a circuit to an electric pump which draws a sample of this expired air from the reservoir sampling region into the analyzer.
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