A pyrometric sensor using a thermistor which is highly resistant to vibrations and heat, comprising a heat-sensing unit formed by inserting a pyrometric thermistor into a metallic protecting tube, connecting lead wires of the thermistor to the protecting tube and a center electrode, and packing a heat-resistant insulating material into said protecting tube. The section of the heat-sensing unit where the thermistor is not located is partly inserted into a hole of an adapter for receiving the protecting tube, an insulating tube is held within the adapter, an upper electrode is secured to the insulating tube by a flange of the electrode itself and a lock nut in thread engagement with a threaded part of the electrode, and the center electrode of the heat-sensing unit is connected to said upper electrode.
A high temperature sensor in which a mixture of a metal fluoride composition and magnesium oxide is filled with pressure into a cylindrical case forming one electrical terminal for supporting a conductive rod forming the other electrical terminal, the high temperature sensor being prevented from malfunction of the sensor due to any vibration and having a high response speed for temperature detection to a change of temperature of the atmosphere.
A sensor used for electrical heating measurement comprises a sensor element having a rod, plural through holes provided straightly through the sensor in the longitudinal direction and plural metal thin wires inserted into and passed through the through holes and an electrically insulating member covering the sensor element, preferably the metal thin wires thinner than through holes are used, spaces around the metal thin wires are filled with ceramics powder and the powder is sintered by heating at lower temperature than the sintering temperature thereof.
An infrared thermal detector includes an infrared thermal sensing element, a load resistor, and a voltage supply means. The infrared thermal sensing element is a pyroelectric material whose electrical conductivity changes with temperature. The circuit and device parameters are chosen such that the detector will have frequency response over a broad band from dc (0 Hertz) to a high frequency determined by the electronic time constant of the circuit. The detector thus has all the advantages of either a pyroelectric detector without a chopper, or a thermistor bolometer having a fast response time.
Here is disclosed a method for measurement of viscosity change in blood or the like comprising steps of disposing a sensor including of an endothermic or exothermic element in blood or the like, stimulating blood or the like so as to cause a viscosity change therein and detecting the viscosity change by continuously measuring any one of changes occurring respectively in an average temperature .theta.w or a surface temperature .theta.s of the sensor containing therein the endothermic or exothermic element, a differential temperature .theta.w-.theta..infin. or .theta.s-.theta..infin. between a temperature .theta..infin. of blood or the like and .theta.w or .theta.s, a kinematic viscosity .nu. of blood or the like and a heat transfer coefficient on the sensor surface. Such measurement may be performed by a sensor comprising an electric insulator through which lead wire extends, metallic wire wound around the electric insulator and connected at opposite ends to the portions of the lead wire exposed on the surface of the electric insulator, and a portion of the electric insulator, around which the metallic wire is wound, being coated with suitable material.
