Chemistry: electrical and wave energy – Apparatus – Electrolytic
Reexamination Certificate
2000-10-23
2002-08-20
Tung, T. (Department: 1743)
Chemistry: electrical and wave energy
Apparatus
Electrolytic
C205S783000
Reexamination Certificate
active
06436258
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to a galvanic-cell gas sensor comprising a cathode and an anode adapted to come into contact with a gas to be detected and sealed in an electrolyte.
DESCRIPTION OF THE INVENTION
A conventional galvanic-cell gas sensor comprises a holder serving as a container to hold an acid electrolyte and having a window and a diaphragm of a water-repellent film of a macromolecular fluorochemical sealed therein, with a cathode of gold (Au) disposed in a segment holding the electrolyte and an anode of lead (Pb) disposed apart from the cathode.
This type of sensor holding an electrolyte has been required to have a liquid-tightness that in turn calls for a complex sealing structure. The use of lead as the unnecessarily large anode has made it extremely difficult to reduce the size of the container.
The anode A has a rod portion B at one end thereof formed by casting or other method or a rod B′ of a metal having a high corrosion resistance to the electrolyte and planted on the anode, as shown in FIG.
5
. Therefore, the anode has been disproportionally sized considering the service life of the sensor, and has hampered the size reduction of the sensor.
SUMMARY OF THE INVENTION
This galvanic-cell gas sensor eliminates the need to form the anode lead segment on the anode from lead (Pb) sheet, while permitting a reduction in the sensor size by coating an appropriate amount of Pb proportional to the sensor life on the anode through accurate control of coating time.
This galvanic-cell gas sensor eliminates the need to form the lead segment on the anode from lead sheet while permitting to reduce the sensor size by coating an appropriate amount of lead proportional to the sensor life on the anode through accurate control of coating time.
Thus, the object of this invention is to provide a galvanic-cell gas sensor of smaller size by making the anode size proportional to the sensor life.
REFERENCES:
patent: 3322662 (1967-05-01), Mackereth
patent: 3406109 (1968-10-01), Molloy
patent: 3429796 (1969-02-01), Lauer
patent: 3510421 (1970-05-01), Gealt
patent: 3948746 (1976-04-01), Poole
patent: 4175028 (1979-11-01), Payton
patent: 5395507 (1995-03-01), Aston et al.
Connolly Bove & Lodge & Hutz LLP
Riken Keikico., Ltd.
Tung T.
LandOfFree
Galvanic-cell gas sensor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Galvanic-cell gas sensor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Galvanic-cell gas sensor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2930929