The invention relates to the technical field of
infrared spectrometer detection and discloses an expiration
detector gas detection device. The device comprises a
gas chamber, a detection part and a
control circuit, wherein the
air chamber comprises more than one
air chamber pipe, medium pipes corresponding to the
air chamber pipes, a first connecting piece and a second connecting piece, the detection part comprises a
light source and a
detector which are respectively arranged on two sides of the air chamber and form a light path, the
control circuit comprises a main board and a
preamplifier board which are electrically connected with each other, the main board provides a pulse type
constant current source, and the pulse type
constant current source is used for supplying power to the
light source in the light path; the front
amplifier board is used for amplifying, filtering and rectifying the
electric signal to form a
light intensity voltage signal. According to the device, a
liquid medium sleeve structure is additionally arranged on the periphery of a current
gas chamber structure, so the temperature of gas in the
gas chamber changes slowly, uniformly and stably, the influence on a test result is reduced, and meanwhile, a more reliable pulse circuit is adopted to control light
waves, the power-on working time of the
light source is shortened, the service life is longer, and flexibility is relatively high.