Retractable humidity sensor for use in corrosion test chambers

摘要

A sensor probe device for monitoring atmosphere within a chamber. The device includes a housing that extends through a wall of the chamber being monitored, and a tubular sleeve that is movably captured within the housing. The sleeve includes an open end for receiving a sensor probe, and a closed end having a plurality of radially spaced apertures that extend through the sleeve wall. The apertures provide an open ribbed portion that exposes the enclosed sensor probe to chamber atmosphere when the sleeve portion is inserted into the chamber. A drive mechanism is attached to either extend the open ribbed portion of the sleeve outward from its shielded position within the housing to an extended position within the chamber, or retract the sleeve portion from the chamber back into its shielded position within the housing. An air supply is provided to inject forced air into the sleeve to maintain sensor probe integrity by purging contaminates through a drain in the sleeve wall, and an external air wipe nozzle is attached to the closed end of the sleeve to provide an air flow along the sleeve to prevent chamber atmosphere from entering the sleeve through the radially spaced apertures.