Measuring chamber for photo-ionisation meter for gas or atmosphere analysis

摘要

The chamber consists of a horizontal bore (2) for the gas flow intercepted by a vertical bore (5) holding the electrodes (6.1,6.2,6.3) from the exciting source (6) opposite an isolating section (7) holding an outer helical electrode (8) and an inner electrode (9) which is either helical or cylindrical in shape. These act as anode and cathode respectively. The outer electrode has gas-permeable sections and there is free space between neighbouring windings (8.1,8.2). This ensures wide dissemination of the gas mixture flowing through the bore in the detector, even if the current speed is very low, giving greater accuracy.