05616158 is referenced by 22 patents and cites 21 patents.

A moisture absorbing media filter includes a housing into which a moisture absorbing material is placed, an end cap fabricated from a clear plastic fits over the housing, exhalations pass through the end cap into an impermeable tube which terminates at substantially the middle of a bore contained in the moisture absorbing material. A tapered chamber follows the impermeable tube and terminates at the end of the moisture absorbing material, a reduced passage follows a pellet filter and leads to an outlet opening, a dyeing agent is deposited into the tapered chamber, a predetermined amount of low vapor pressure, water soluble liquid is also deposited into the tapered chamber. Exhalations enter the inlet opening and pass through the impermeable tube into the tapered chamber, low vapor pressure, water soluble liquid deposited in the tapered chamber allows moisture in the gas to be absorbed by the moisture absorbing material but not the gas itself. Moisture absorbed by the filter forces the dyeing agent outward to the cylindrical body of the housing and to the end cap thus indicating that the filter should be discarded. Gas passes through a pellet filter which will not allow the gas to pass if the pellet filter has become substantially saturated with moisture. The gas then passes into a moisture filter which contains a second pellet filter which operates as the first pellet filter and finally, the gas passes into a monitoring system.

Title
Moisture absorbing media filter
Application Number
8/440943
Publication Number
5616158
Application Date
May 15, 1995
Publication Date
April 1, 1997
Inventor
Robert H Ricciardelli
Waukesha
WI, US
Bruce S Biendarra
West Bend
WI, US
Agent
Donald J Ersler
Assignee
Pryon Corporation
WI, US
IPC
B01D 35/143
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