Abstract Apparatus for measuring the temperature at the surface of thin elongated objects such as a metallic wire by measurement of the infrared radiation emitted from the surface of the object comprises a variably heated metallic compensating radiator provided with an opening through which the object passes and a rotatable chopper wheel interposed between the object surface and the compensating radiator. The side of the chopper wheel facing towards the compensating radiator is made radiation reflective and a radiation detector is positioned to receive in alternation the infrared radiation emitted from the surface of the object and which passes intermittently through the rotating chopper wheel and infrared radiation emitted by the compensating radiator and which is reflected intermittently into the detector from the reflective side of the chopper wheel. The detector produces at its output an alternating current signal determined by any temperature differential existing between the object and compensating radiator, and the heat supply to the compensating radiator is varied in accordance with the signal in such sense as to reduce the signal to zero whereby the temperature of the compensating radiator then equals the temperature of the object.
Apparatus for measuring the temperature at the surface of a relatively thin elongated object by measurement of the infrared radiation emitted from the surface thereof which comprises a compensating radiator constituted by a thermally conductive metallic body having a cavity therein, said metallic body including a bore therein communicating with said cavity and through which the elongated object is inserted into said cavity, a rotatable chopper wheel mounted for rotation within said cavity, an infrared radiation detector positioned to receive in alternation the infrared radiation emitted from the surface of the elongated object within said cavity and which passes intermittently through said rotating chopper wheel and infrared radiation emitted from the wall of said cavity and which is reflected intermittently into said detector by the side of said chopper wheel which faces away from the object within said cavity, said detector producing at its output a signal determined in accordance with the temperature differential existing between the portion of the elongated object within said cavity and said metallic body, and means for heating said metallic body in accordance with said signal in such sense as to reduce said signal to zero whereby the temperature of said metallic body then equals the temperature of the elongated object.
Claim 2
Dependent Claim
206 words
Apparatus for measuring the temperature at the surface of a relatively thin elongated object by measurement of the infrared radiation emitted from the surface thereof which comprises a compensating radiator constituted by a thermally conductive metallic body having a cavity therein, said metallic body including a bore therein communicating with said cavity and through which the elongated object is inserted into said cavity, a rotatable chopper wheel mounted for rotation within said cavity, an infrared radiation detector positioned to receive in alternation the infrared radiation emitted from the surface of the elongated object within said cavity and which passes intermittently through said rotating chopper wheel and infrared radiation emitted from the wall of said cavity and which is reflected intermittently into said detector by the side of said chopper wheel which faces away from the object within said cavity, said detector producing at its output a signal determined in accordance with the temperature differential existing between the portion of the elongated object within said cavity and said metallic body, and means for heating said metallic body in accordance with said signal in such sense as to reduce said signal to zero whereby the temperature of said metallic body then equals the temperature of the elongated object.
Claim 3
Dependent Claim
62 words
Apparatus as defined in claim 1 for measuring the surface temperature of a thin elongated object wherein said bore in said metallic body extends completely therethrough between its opposite end faces thereby enabling the thin elongated object to be passed completely through the body thereby bringing successive longitudinal surface portions thereof into communication with said cavity for measurement of its surface temperature.
Claim 4
Dependent Claim
82 words
Apparatus as defined in claim 1 for measuring the surface temperature of a thin elongated object wherein the means for heating said metallic body is constituted by a coil surrounding the periphery thereof, and wherein said bore in said metallic body extends completely therethrough between its opposite end faces thereby enabling the thin elongated object to be passed completely through the body so as to bring successive longitudinal surface portions thereof into communication with said cavity for measurement of its surface temperature.