Temperature monitoring device and thermocouple assembly therefor

Temperature monitoring apparatus for measuring the temperature at a surface of a body, composed of: a hollow guide member (24,26) secured to a support member (28); a hollow guide tube (22) having a first end disposed at the guide member (24,26), the interior of the guide tube (22) being in communication with the interior of the guide member (24,26) and the guide tube (22) being movable relative to the guide member (24,26); a thermocouple assembly (10,16) extending through, and movable relative to, the guide tube (22) and the guide member (24,26) and having an end provided with a tip for engaging the body surface (18); a first biasing element (38) connected between the thermocouple assembly (10,16) and the guide tube (22) for permitting relative movement between the thermocouple assembly (10,16) and the guide member (24,26); and a second biasing element (40) connected between the guide tube (22) and the guide member (24,26) for resiliently urging the first end of the guide tube (22) toward the body surface (18) while permitting relative movement between the first end of the guide tube (22) and the guide member (24,26), the biasing elements acting to resiliently urge the thermocouple assembly (10,16) tip toward the body surface (18). A thermocouple assembly (10,16) including: a cylindrical metal sheath (10) having an exterior surface and a closed end (14) defining a thermocouple tip, and enclosing a thermocouple junction (6) located adjacent the tip; a convection shield (16) having the form of a hollow cylinder disposed around the sheath (10) in the vicinity of the tip; and a coating (17) of a material having a low thermal emissivity on the exterior surface of the shield (16).