Abstract: A temperature sensor which can achieve accurate temperature measurement in a magnetic field and accurate temperature measurement over a broader temperature range and, further, provides a temperature sensor which, in the correction of a temperature characteristic on a resistance value of the present temperature sensor, can reduce, to a minimal possible extent, an error between a value found from an approximation equation and a measured value, includes a cylindrical type sensor including a temperature-sensitive device having a micro-crystalline semiconductor thin film formed over an insulating substrate and four electrodes connected to the thin film, a cylindrical container made of a nonmagnetic metal and holding the temperature-sensitive device, together with a helium gas, hermetically sealed therein and four conductors hermetically mounted at the bottom of the container and connected to the corresponding electrodes of the temperature-sensitive device, with the micro-crystalline semiconductor thin film 2 being

Abstract: A ferrite device for sensing temperature is disclosed, which is useful for apparatuses such as hot water vessels, fire alarms, and general electronic apparatuses. More specifically, the ferrite device for sensing temperature is manufactured by stack-printing two or more ferrite layers having different Curie temperatures (Tc). Therefore, a mass production is possible with a low manufacturing cost, and control of the process conditions is easy. The temperature sensing ferrite device includes: upper and lower layers composed of a single ferrite material; a plurality of stacked layers stacked between the upper and lower layers and consisting of two or more ferrite subregions; each of the ferrite subregions of one of the plurality of stacked layers has a composition and a shape that are the same as a ferrite subregion in another of the plurality of stacked layers screw type electrodes provided on the respective ferrite subregions.

Abstract: An optical transmitter for converting a thermocouple voltage into an optical pulse train and a low pass input filter are contained in respective spaces in a soft magnetic housing. The input filter is in lead wires from a thermocouple whose hot junction is embedded in the tip of the insulator of a spark plug of an internal combustion engine. The housing itself forms part of or is connected to the H.T. lead to the centre electrode of the spark plug. The housing is surrounded by insulating material which is itself surrounded by an earthed screening casing. The low pass filter is symmetrically constructed, both electrically and mechanically.The filter prevents interference from reaching the circuitry of the optical transmitter and the housing and the casing prevents the generation and transmission of radio interference.

Abstract: A temperature sensor has a body whose thermal expansion is evaluated in the event of a change in temperature, there being deposited on the body a layer which has a layer structure containing less than 8% by weight of phosphorus, preferably containing up to 3% by weight of phosphorus, up to 2% by weight of an element of main group IV or main group V, in particular antimony, and up to 5% by weight of a transition metal element, in particular cobalt. The percentages by weight resulting from the sum being increased up to 100% with nickel. The layer modifies the magnetic flux in a coil arrangement comprising at least one coil. This change in the magnetic flux in the coil arrangement is evaluated and the change in the magnetic flux being detected as a change in the inductance. The change in length of the body and the change in temperature are deduced therefrom.

Abstract: A method for thermal environment sensing utilizing superconducting materi finds utility in the production of low power cryogenic flow meters, bolometers, level detectors and other types of thermal environment sensors. A device for determining the first and second derivatives (dV/dI and d.sup.2 V/dI.sup.2) utilizes a ramped current until a set value of the first derivative (dV/dI) is achieved, the current supply being placed in a feedback mode to maintain the first derivative constant and monitoring any changes in the second derivative (d.sup.2 V/dI.sup.2) which indicate changes in the thermal environment. Alternatively, the second derivative is maintained constant and the first derivative is measured. Any parameter which is indicative of the non-linearity of the relationship between the voltage and the current can be utilized instead of the second derivative.

Abstract: A temperature history indicator for a boiler tube or other thing can take the form of a clip fixed around the tube or thing. The indicator is made of a ferrite-containing duplex stainless steel non-structural piece of alloy having at least about 63 weight % of iron, 23-27% chromium, 5-11% nickel, and the balance comprising other components no one of which exceeds 2.0%. Preferably, the balance of the alloy includes any one or more of 0.005-0.009% carbon, 0.3-0.8% silicon, 1.0-2.0% manganese, 0.002-0.006% phosphorous, 0.003-0.007% sulphur, 0-0.02% molybdenum, and 0-0.02% copper. The thing is associated beforehand with the alloy in such a way as to irreversibly alter its magnetic properties and after exposure to temperature, the time and/or temperature are deduced by the loss in magnetic permeability.

Abstract: The present invention is a quantitative method for measuring the total heat flux, and of deriving the total power dissipation, of a heat-fluxing object which includes the steps of placing an electrical noise-emitting heat-fluxing object in a liquid helium bath and measuring the superfluid transition temperature of the bath. The temperature of the liquid helium bath is thereafter reduced until some measurable parameter, such as the electrical noise, exhibited by the heat-fluxing object or a temperature-dependent resistive thin film in intimate contact with the heat-fluxing object, becomes greatly reduced. The temperature of the liquid helum bath is measured at this point. The difference between the superfluid transition temperature of the liquid helium bath surrounding the heat-fluxing object, and the temperature of the liquid helium bath when the electrical noise emitted by the heat-fluxing object becomes greatly reduced, is determined.

Abstract: A device is provided for measuring radiant energy, the device comprising a substrate; a bolometer formed from a high T.sub.c superconducting material disposed on the substrate in an area that is about 1.times.5 .mu.m.sup.2 and about 0.02 .mu.m in depth; and a planar antenna disposed on the substrate and coupled to receive radiation and to impart the received radiation to the bolometer.

Abstract: A method and the instrument associated therewith for determining the Curie points of ferromagnetic materials which display no significant abrupt change in heat absorption around the Curie points thereof by means of a conventional thermal analyzer with externally added facilities to provided an external magnetic field. The abrupt change of heat absorption of the ferromagnetic materials is increased by adding the external magnetic field to increase the magnetic anisotropy energy thereof and to strengthen the spontaneous magnetization thereof.

Abstract: A temperature history indicator for a boiler tube or other thing can take the form of a clip fixed around the tube or thing. The indicator is made of a ferrite-containing duplex stainless steel non-structural piece of alloy having approximately 63 weight % of iron, 23-27% chromium, 5-11% nickel, and the balance comprising other components no one of which exceeds 2.0%. Preferably, the balance of the alloy includes any one or more of 0.005-0.009% carbon, 0.3-0.8% silicon, 1.0-2.0% manganese, 0.002-0.006% phosphorous, 0.003-0.007% sulphur, 0-0.002% molybdenum, and 0.006% phosphorous, 0.003-0.007% sulphur, 0-0.02% molybdenum, and 0-0.02% copper. The thing is associated beforehand with the alloy in such a way as to irreversibly alter its magnetic properties and after exposure to temperature, the time and/or temperature are deduced by the loss in magnetic permeability.

Abstract: A superconducting transition edge bolometer is constructed using high critical temperature conducting films by stabilizing a substrate of magnesium oxide or sapphire with a silicon base that is bonded to the substrate using a thermally conductive bonding layer. The base is etched away in the region of the desired radiation detecting portion of the superconductor establishing a controlled thermal connection between the detecting portion and the base which base serves as a thermal bath for the bolometer.

Abstract: A cryogenic microwave test chamber consists of a dry-sample receiving char which is partly immersed in liquid nitrogen. Waveguides from either end of the interior of the dry chamber are connected to and sealed to outgoing waveguides in regions immersed in the liquid nitrogen. Dry nitrogen is introduced through the waveguide and is circulated through the dry chamber to prevent condensation therein during cooling. A heat conductive metal tube surrounds the dry chamber and is spaced therefrom and acts as a heat barrier. Waveguide flanges on the opposite ends of the dry chamber slidably seal the chamber.

Abstract: The present invention provides a hydraulic sensor for quench detection and location in a superconductor, and particularly a superconductor used to form an inductor or a magnet. The sensor consists of an insulating tube (1) adjacent to and preferably co-wound with the super conductor (2) and filled with a supercooled working fluid (3). When joule heating occurs in the superconducting conductor as a result of a portion of it becoming normal, the heat is transferred directly to the corresponding portion of the adjacent tube (1). This heat causes the vapor pressure of the working fluid (3) at that point in the tube to change. This change in pressure propagates in both directions at the speed of sound in the working fluid. By detecting with sensors (6,7) when a change in pressure arrives at the ends (5,6) of the tube (1) and calculating the difference between the arrival times, not only can a quench be detected, but the exact location of the quench initiation region can be determined.

Abstract: A superconducting temperature controller that can sense the temperature of an area and also heat the enclosed area. A superconducting thin film resistor mounted on a substrate is disposed in an enclosed housing that forms a vacuum. Also disposed within the housing is a heat sink that keeps the temperature inside the housing below the transition temperature of the superconducting material that forms the thin film resistor. By applying a constant voltage to the thin film resistor, the temperature of the substrate and thin film resistor can be maintained at a predetermined level that is within the transition temperature region of the superconducting material being used.

Abstract: A level gauge and measurement method are provided using a sensing element comprising a superconductive alloy represented by the formula:Mo.sub.a Ru.sub.b Z.sub.cwherein Z is phosphorous, boron, or a mixture of phosphorous and boron,b has a value of about 20 to about 40,c has a value of about 10 to about 30, anda+b+c=100.The sensing element has a superconductivity critical temperature of at least 4.2K and is useful for measuring the level of liquid helium independently of pressure fluctuations in the reservoir vessel.

Abstract: A temperature sensor comprises a thin layer of material the composition of which varies gradually over the layer thickness. The material is superconductive below a critical temperature the value of which depends on the composition of the material. The layer is connected, by means of electrodes to an electronic circuit for supplying current to the sensor and processing a temperature-dependent signal produced by the sensor.

Abstract: A superconducting device is disclosed with the device having multiple layers of thin film configured to achieve highly sensitive measurements based upon temperature. The device is implemented, in simplest form, as a stripline having a ground plane layer of superconductor, a configured layer of superconductor, and a dielectric layer between the ground plane layer and the configured layer. The device is operated at a temperature just below the transition temperature of the superconducting materials utilized so that the inductance of the device depends substantially upon temperatures encountered, with highest sensitivity resulting when at least one of the superconducting layers has a thickness that is small relative to the magnetic penetration depth of the superconducting material utilized.

Abstract: A temperature testing device in which a sample-receiving sealable chamber from which a specimen can be easily detached and a cooling portion of a refrigeration unit are inserted into a single vacuum vessel, and in which a gaseous refrigerant is circulated between the cooling portion of the refrigeration unit and the sample-receiving chamber so that the sample-receiving chamber can be cooled.

Abstract: A vessel for the storage and monitoring of nuclear fuel materials incorporates a device (12) within its interior for providing an externally detectable signal indicating whether any temperature rise has occurred. The device (12) comprises a magnet (32) attracted towards a boundary wall (11) of the vessel and maintained in that position by a temperature-sensitive element such as a thermal link (38). The magnet (32) is subjected to an oppositely directed force by a spring (30), which is effective to drive the magnet (32) away from the wall (11) in the event of a substantial temperature rise within the vessel thereby producing an externally detectable change in magnetic flux.

Abstract: A thermometer is described having a broad voltage-temperature characteristic rendering it useful in making temperature measurements from below 1.degree. K. to above 500.degree. K. The thermometer employs a gallium aluminum arsenide diode and displays improved sensitivity over more conventional diode devices. In addition to providing for improved polynomial fitting for calibration curve purposes, the diode also exhibits an advantageously low magnetic field dependence.

Abstract: A method and apparatus for contact-free measurements of stress, temperature, torque, or other physical conditions which affect the magnetic properties of a non-ferromagnetic test object 10. The non-contacting magnetic sensor detects the large Barkhausen effect. Magnetic layers 12,14 of thin magnetic material are formed on surface 16 of test object 10. An easy axis of magnetization is formed on the magnetic layers 12,14 making them susceptible to the large Barkhausen effect. A physical condition, such as stress 17,17', is applied to test object 10 and magnetic field 18 is generated by source 19. Magnetic field 18 causes large Barkhausen effects to be generated in magnetic layers 12,14 which are detected by detector 20. The level of the physical condition is a function of the time required for the large Barkhausen effect to occur in the different magnetic layers 12,14.

Abstract: A threshold temperature is detected by providing a sensor (12) comprising a magnet (13) inside a ferromagnetic shield (14) which has a lower Curie point than that of the magnet. Below threshold the sensor is magnetically characterless. Above threshold the sensor displays a magnetic character which is detected at a solid-state magnetometer (16). In one application the sensor is located in a breeder fuel sub-assembly (20) at the breeder/fuel region (22) of a fast-fission nuclear reactor and the magnetometer is located in a fuel sub-assembly (21). In another application the sensor is located inside a sealed containment vessel and the magnetometer is located outside the vessel.

Abstract: A thermometer comprises a first sample space having a liquefiable gas sealed therein and a second sample space partitioned from the first sample space by a pressure difference detecting element and having a liquefiable gas sealed therein in conjunction with an adsorbent. As this thermometer is cooled to cryogenic temperatures, the second sample space is vacuumized by the action of the adsorbent. As the pressure difference detected by pressure difference detecting element at this is equal to the vapor pressure in the first sample space, the temperature can be accurately measured from the detected pressure difference.

Abstract: A detector is disclosed including a temperature sensitive amorphous magnetic alloy which shows a Curie point of not higher than 200.degree. C. and whose composition is represented by the formula:(M.sub.1-a Ni.sub.a).sub.100-z X.sub.zwherein M=Co or Fe; X=at least one of P, B, C and Si; 0.2.ltoreq.a.ltoreq.0.8 when M is Co, or 0.4.ltoreq.a.ltoreq.0.9 when M is Fe; and 15.ltoreq.z.ltoreq.30.

Abstract: A thermometer capable of providing temperature measurement over a wide temperature range comprises at least one temperature detection unit consisting of a first superconductor as a core, and a normal conductor and a second supercondutor sequentially superposed coaxially on the first superconductor; a first power source disposed to pass electric current between the first and second superconductors, a second power source disposed between the opposite terminals of the first superconductor, and a voltmeter connected to the first and second superconductors. This thermometer effects measurement of temperature by fixing the value of the electric current from the first power source and changing the value of the electric current from the second power source thereby causing cyclic change of the voltage and measuring the increment of electric current from the second power which is required to cause one cycle of change of the voltage.

Abstract: A method and apparatus for monitoring the state of the surface of a moving body wherein a four-terminal eddy-current coil circuit is connected in a feedback loop of an RC resonator. The eddy-current coil circuit is placed in proximity to the monitored surface of the moving body and connected in the feedback loop of an RC resonator such that a change in the state of the surface of the moving body results in a change in the conductivity thereof, which conductivity change produces a phase displacement changing the output frequency of the RC resonator. During operation, a first data set is obtained from the coil circuit and RC resonator presenting a first runout profile of the body when the monitored state is in an initial state. The first data set is stored in a memory, and a subsequent profile is derived to obtain a second data set indicative of the operational state of the surface of the moving body.

Abstract: A method for indicating the thermal state of cooking appliances with an optical and/or acoustic signalling device, comprising the steps of: counting forward from a starting number in response to the heating means of the cooking appliance being switched on; and, counting backwards after the heating means of the cooking appliance has been switched off, the signalling device being switched on when the count exceeds a first number and being switched off when the count falls below a second number.

Abstract: A temperature sensor includes a permanent magnet placed on an object whose temperature is to be measured, a magnetically soft member located within the magnetic field of the magnet and an electrical coil placed around the magnetically soft member. The electrical coil is supplied with voltage pulses at one end while the other end is connected to a resistor in series to detect a voltage drop. The time lag of the voltage drop with respect to the voltage pulse is represented by an analog voltage or a digital code. A change in temperature changes the field strength of the magnet and hence the flux in the magnetically soft member. The coil senses the change in flux as a change in the time lag and thus measures the temperature.