System for controlled humidity tests

Claim 1

A system for controllably measuring permeability of a test gas through a membrane under conditions of controllable relative humidity of the test gas, wherein the test gas is obtained from a source of dry test gas, comprising: (a) a gas bubbler means for bubbling said dry gas through a liquid-filled container to form a humidified test gas reservoir; (b) a gas conduit coupled between said source of dry gas and said gas bubbler, said gas conduit including means for diverting a portion of said dry gas from entering said gas bubbler means; (c) means for controllably connecting and mixing dry test gas from said means for diverting and from said humidified test gas reservoir, and for conveying said mixed dry and humidified test gas; (d) a test cell having a first chamber connected to said means for conveying said mixed dry and humidified test gas, and having a second chamber, said first and second chambers being separated by a membrane; (e) a gas sensor coupled to said second chamber, said gas sensor being adapted to measure trace amounts of said test gas; and (f) temperature control means connected to said gas bubbler means, said gas conduit, said means for conveying said mixed dry and humidified test gas and said test cell, said temperature control means having further means for controlling the temperature of said test gas and for insuring that the temperature of said test gas in said test cell is lower than the temperature of said test gas in all other elements connected by said temperature control means.

Claim 2

A system for controllably measuring permeability of a test gas through a membrane under conditions of controllable relative humidity of the test gas, wherein the test gas is obtained from a source of dry test gas, comprising: (a) a gas bubbler means for bubbling said dry gas through a liquid-filled container to form a humidified test gas reservoir; (b) a gas conduit coupled between said source of dry gas and said gas bubbler, said gas conduit including means for diverting a portion of said dry gas from entering said gas bubbler means; (c) means for controllably connecting and mixing dry test gas from said means for diverting and from said humidified test gas reservoir, and for conveying said mixed dry and humidified test gas; (d) a test cell having a first chamber connected to said means for conveying said mixed dry and humidified test gas, and having a second chamber, said first and second chambers being separated by a membrane; (e) a gas sensor coupled to said second chamber, said gas sensor being adapted to measure trace amounts of said test gas; and (f) temperature control means connected to said gas bubbler means, said gas conduit, said means for conveying said mixed dry and humidified test gas and said test cell, said temperature control means having further means for controlling the temperature of said test gas and for insuring that the temperature of said test gas in said test cell is lower than the temperature of said test gas in all other elements connected by said temperature control means.

Claim 7

A system for measuring the gas permeability of a membrane under conditions of controlled humidity of said gas, by controllably admitting a flow of humidified test gas into a firstchamber and controllably admitting a flow of carrier gas into a second chamber, the first and second chambers being separated by said membrane, comprising: (a) a source of dry test gas and a source of dry carrier gas; (b) a first gas bubbler connected to said source of dry test gas, and a second gas bubbler connected to said source of dry carrier gas; each of said first and second gas bubblers having means for bubbling said connected gas through a liquid reservoir and for collecting said gas above said liquid reservoir in a humidified gas reservoir; (c) first means for controlling the temperature of the gas in each of said humidified gas reservoirs; (d) a first gas mixer coupled between said source of dry test gas and said first gas bubbler humidified gas reservoir, including means for controllably mixing a flow of dry test gas with a flow of humidified test gas; a second gas mixer coupled between said source of dry carrier gas and said second gas bubbler humidified gas reservoir, including means for controllably mixing a flow of dry carrier gas with a flow of humidified carrier gas; (e) second means for controlling the temperature of the respective controllably mixed test and carrier gases; (f) a first gas conduit coupled between said first gas mixer and said first chambe;; a second gas conduit coupled between said second gas mixer and said second chamber; (g) third means for controlling the temperature of the respective gases in the first and second conduits; (h) fourth means for controlling the temperature of the respective gases in said first and second chambers; (i) means coupled to said second chamber for measuring trace quantities of said test gas in said second chamber; and (j) means for adjusting said first, second, third and fourth means for controlling temperature to insure that the gas temperature in said first and second chambers is the lowest of all controlled temperatures.

Claim 8

A system for measuring the gas permeability of a membrane under conditions of controlled humidity of said gas, by controllably admitting a flow of humidified test gas into a firstchamber and controllably admitting a flow of carrier gas into a second chamber, the first and second chambers being separated by said membrane, comprising: (a) a source of dry test gas and a source of dry carrier gas; (b) a first gas bubbler connected to said source of dry test gas, and a second gas bubbler connected to said source of dry carrier gas; each of said first and second gas bubblers having means for bubbling said connected gas through a liquid reservoir and for collecting said gas above said liquid reservoir in a humidified gas reservoir; (c) first means for controlling the temperature of the gas in each of said humidified gas reservoirs; (d) a first gas mixer coupled between said source of dry test gas and said first gas bubbler humidified gas reservoir, including means for controllably mixing a flow of dry test gas with a flow of humidified test gas; a second gas mixer coupled between said source of dry carrier gas and said second gas bubbler humidified gas reservoir, including means for controllably mixing a flow of dry carrier gas with a flow of humidified carrier gas; (e) second means for controlling the temperature of the respective controllably mixed test and carrier gases; (f) a first gas conduit coupled between said first gas mixer and said first chambe;; a second gas conduit coupled between said second gas mixer and said second chamber; (g) third means for controlling the temperature of the respective gases in the first and second conduits; (h) fourth means for controlling the temperature of the respective gases in said first and second chambers; (i) means coupled to said second chamber for measuring trace quantities of said test gas in said second chamber; and (j) means for adjusting said first, second, third and fourth means for controlling temperature to insure that the gas temperature in said first and second chambers is the lowest of all controlled temperatures.