Surface-temperature sensing method and apparatus.

摘要

An apparatus suitable for measuring the surface temperature of a moving strip at an elevated temperature comprises a sensing head 10 connected to a pneumatic actuator 23 through a ball joint 22. Air under pressure is supplied to a chamber in the head 10 and flows through a ring of passages 16 to form an air cushion between the sensing head and the surface S whose temperature is to be measured. Part of the air flows inward across the surface S to a central aperture 19 in the bottom plate 17 of the head 18 and its temperature is measured by a thermocouple 21 in the aperture 19. Aperture 19 leads to a cavity 18 above plate 17 and the cavity is vented by passages 20. The temperature recorded by the thermocouple is a measure of the temperature of surface S.