UV gas discharge tubes

Details UV gas discharge tubes UV gas discharge tubes

2005-09-07

2009-08-18

Porta, David P (Department: 2884)

Radiant energy

Invisible radiant energy responsive electric signalling

Including a radiant energy responsive gas discharge device

Reexamination Certificate

active

07576331

ABSTRACT:
In use of a UV gas discharge tube (such as used in flame monitoring apparatus), an electric field is periodically applied in the tube, each application of the field being followed by an ‘off’ period in which the field is removed. During this process, the mean value of the statistical lag Tsis measured over a predetermined time duration (the statistical lag is the time lag after each application of the electric field to the tube before conduction (if any) takes place). If the statistical lag lies within region I, the flame is judged to be present. If the statistical lag lies in region II, the flame is judged to be off (and a warning may be signalled). If the statistical lag lies in region III, a fault in the tube is signalled. This may be a “field emission” fault whereby free electrons are generated by the applied electric field, without the presence of UV radiation or it may be a “multiple counting” fault. Here, contamination of the gas within the tube causes the time required to de-ionise the gas, when the electric field is removed, to be increased. A multiple counting fault may be confirmed by monitoring each conduction of the tube and checking whether there is an immediately following conduction. A multiple counting fault may also be checked by increasing the lengths of the ‘off’ periods of the electric field and checking whether the mean statistical lag increases. The use of a supplementary light source is also disclosed which periodically illuminates the tube to check whether it has become room-light sensitive—that is, sensitive to normal ambient light.

REFERENCES:
patent: 3594746 (1971-07-01), Pileika et al
patent: 4736105 (1988-04-01), Fonnesbeck
patent: 4823114 (1989-04-01), Gotisar
patent: 5026272 (1991-06-01), Takahashi et al.
patent: 5194728 (1993-03-01), Peterson
patent: 5227640 (1993-07-01), Nomura et al.
patent: 37 06 986 (1988-09-01), None
patent: 0 150 233 (1985-08-01), None
patent: 0 274 275 (1988-07-01), None
patent: 1 515 116 (1978-06-01), None
patent: 55-1547 (1980-01-01), None
patent: WO 03091748 (2003-11-01), None

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