Temperature-controlled apparatus for fluid permeation or the like

Claim 1

Permeation apparatus comprising a cylindrical housing with a metal cylindrical side wall, a hollow cylindrical core with a cylindrical side wall coaxially within said housing, the outer surface of the cylindrical side wall of said core and the inner surface of the cylindrical side wall of said housing delimiting therebetween a thin flow passage for conducting carrier gas between opposite ends of said core over the periphery of said core, the thickness of said flow passage being small compared with the thickness of said housing side wall and said passage having a high ratio of length to thickness, means for admitting carrier gas to one end of said flow passage, means coupling the other end of said flow passage to one end of the interior of said core, closures for said housing at opposite ends thereof, said flow passage being isolated from the interior of the core at said one end of said passage, whereby the carrier gas is constrained to flow along the length of said passage and then to enter the interior of the core at said one end thereof, means for providing an outlet from said core at the opposite end thereof, means for supporting in the interior of said core a permeation fluid container having a wall permeable to fluid in the container, heater means comprising an electrical heater mounted exteriorly of the housing side wall for supplying heat to the exterior of said housing, means including a temperature sensor sensing the temperature of the carrier gas which enters the interior of the core for controlling said heater means to control the temperature in said housing, and insulation means for isolating the exterior of said housing from the ambient.