Temperature sensing device

Claim 1

In a combination which includes a continuous-casting mold adapted to contain liquid metal and a mechanism for indicating the level of the liquid metal therein; said mold including spaced apart inner and outer walls, said inner wall containing the liquid metal and being itself of a metal which has a high thermal conductivity, the space between said walls forming a passage through which water circulates to cool said inner wall; said mechanism including a row of vertically spaced temperature sensing devices on said mold and a measuring circuit connected to said devices for indicating the level at which there is an abrupt change in the temperature of said inner wall; the improvement in which each of said devices comprises: a respective probe having a point at one end and being of a metal dissimilar to the metal of said inner wall; and means mounting said probe in said outer wall and insulating said probe therefrom, said probe extending across said passage to said inner wall and being exposed to water circulating through the passage; said mounting means including a housing fixed in said outer wall and having a bore receiving said probe, a spring acting against said housing and said probe urging said probe into contact with said inner wall, whereby said point remains in contact with said inner wall as the parts undergo thermal expansion and contraction and forms therewith a thermocouple transmitting a voltage signal to said measuring circuit, and seals between said housing and said outer wall and between said probe and said housing.