Abstract: An air flow rate meter for detecting an air flow rate in a wide operating temperature range. A heating temperature of a heat generating resistor for detecting an intake air flow rate is set on the basis of an intake air temperature or a current flowing through the heat generating resistor. The heating temperature of the heat generating resistor is kept at an optimum value determined from a look up table stored in a read only memory.

Abstract: A method and apparatus for measuring mass flow rates and other characteristics of a fluid in a large conduit uses a sensor circuit having a heater/thermometer, a reference resistor, and a thermometer resistor arranged in four-wire network to enable measurement of all characteristics of the resistor network. That sensor circuit is preferably mounted on an interior wall surface of a support tube. A plurality of such support tubes, each having a plurality of sensors within the support tube, are mounted in an array in the cross section of the duct. A cleaning plate for cleaning the exterior surface of the support tube permits calibration of the network while cleaning. A program for using the circuit to calculate values of interest and to display desirable output data is also disclosed, as is a program for controlling the cleaning/calibration cycle.

Abstract: A flowmeter comprises an output cut-off circuit controlled by a command signal generated by a flow switch, wherein the flow switch generates a command signal switching on the transmission of an electrical signal representing the flow rate of media to an output terminal, when the flow rate of media being measured by the flowmeter is greater than a preset threshold value, and switches off the transmission of the electrical signal representing the flow rate of media to the output terminal, when the flow rate of media is less than the preset threshold value.

Abstract: An ultrasonic rail flaw detection system and technique are described for the detection of flaws in the sides of rail heads. An ultrasonic transducer is oriented, sized, and so-located so as to produce an ultrasonic beam within the head whereby at least a portion of the beam will intersect a lower side corner independent of the curvature of the rail head running surface and the amount of head wear. The presence of premature reflections or the or absence of reflections can be used to detect flaws such as vertical fractures in the rail head. The side-looker is so oriented as to produce a beam in the rail head that lies within 45.degree. to 75.degree. of the normal to the rail surface. The side-looker can further be so located that its beam does not interfere with or be interfered by beams from other transducers used to investigate the rail and mounted in the same wheel assembly as the side-looker.

Abstract: A unit and system for sensing fluid velocity which is particularly well suited for use in the control system of an HVAC unit. A salient feature of the system is the combination of heat generating structure, a plurality of thermally conductive elements, and thermal insulation between the heat generating structure and a fluid flow path. Each of the conductive elements is in thermal communication with the heat generating structure at one end and the fluid flow path at a second end. As a result, heat transfer to the fluid is channelled through the conductive elements. This achieves a distributed heat flow path which results in an efficient and accurate heat flow measurement.

Abstract: A magnetic flowmeter provides a first alternating electrical signal with at least a portion thereof comprising a first electromotive force generated by an electromagnetic interaction between an alternating magnetic field and the velocity of an electrically conductive fluid moving transversely across the alternating magnetic field, wherein the first electromotive force varies as a function of the velocity of the electrically conductive fluid, and a second alternating electrical signal with at least a portion thereof comprising a second electromotive force generated by an electromagnetic induction from the alternating magnetic field and other ambient electromagnetic field, wherein the second electromotive force is independent of the velocity of the electrically conductive fluid, and determines the velocity of the electrically conductive fluid as a function of a phase angle difference between the first and second alternating electrical signals.

Abstract: A compact, 4-chamber gas meter comprising crankpost and valve drive mechanisms whereby each reciprocating valve moves from a stroke shifting point near center to a stroke endpoint and back to said stroke shifting point with each 180.degree. rotation of the crankpost and each stroke of each diaphragm occurs over said 180.degree. rotation of the crankpost.

Abstract: A high volume, low RPM, low noise, low wear and long life flowmeter uses inter-engaging double helical four-lobe rotors. The meter is made with ball bearings or bearingless. The double helical nature of the teeth provides no axial loads and no side loads or end loads, and uses true gear designs with very large pockets. A high contact ratio is provided with only four teeth, reducing and eliminating noise and pulsing output, increasing working volume and decreasing speed and wear.

Abstract: A multi-phase fluid flow meter based on passive and non-intrusive acoustics is described for use in field applications on pipes. The present design uses the pipe's characteristic acoustic frequency and its amplitude variation in conjunction with a differential pressure measurement to obtain the total mass flow rates and mass flow rates of each phase. In addition to the mass flow rates the void/liquid fraction, fluid velocities and densities become viable estimates. Instrument construction is simple and very robust, allowing for use in extreme environments. This includes down hole as well as surface measurements.

Abstract: The flow velocity of the medium is determined with the aid of a temperature-dependent resistor. The measurement probe is located in a partially open measurement chamber. The measurement chamber has an inlet port and an outlet port of different sizes. Only if the flow enters through the smaller inlet port and exits through the larger outlet port, is the actual flow velocity measured. When the flow enters through the outlet port, the measured value is less by about 30%. From this difference the direction of flow can be clearly determined.

Abstract: A pressure detection gage for a semiconductor pressure sensor includes a gage portion, a pair of lead out portions, and an isolation layer. The gage portion is formed on the upper surface of a semiconductor substrate of the first conductivity type, has a predetermined sheet resistance, and serves as a piezoelectric region. The pair of lead out portions are formed as heavily doped semiconductor regions of the second conductivity type on the surface of the semiconductor substrate and are electrically connected to two ends of the gage portion. The isolation layer is formed from a lightly doped semiconductor region of the second conductivity type formed in the semiconductor substrate to surround the lead out portions.

Abstract: There is disclosed an apparatus and method for collection of both dry and wet precipitation. The invention involves the use of a dynamic flowing fluid surface for the collection of precipitation for temporary storage and subsequent analysis. The use of a dynamic system prevents exposure of the collected precipitation to other meteorological conditions which may alter, volatilize or destroy the precipitation material.

Abstract: An arrangement for measuring a liquid flow through a liquid spray nozzle which provides liquid from a header in a flue gas desulfurization system includes a spool having an outlet and connected to the header and the nozzle for channeling the liquid from the header to the nozzle. The outlet permits an amount of the liquid to be channeled out of the spool; and a conduit is connected to the outlet of the spool for channeling the amount of the liquid from the outlet to the outside of the vessel. A measuring device such as a pressure gauge is located outside of the vessel and is operatively connected to the conduit in order to determine the liquid flow of the nozzle based on the pressure of the liquid channeled through the conduit. A flushing device is operatively connected to the conduit for channeling a flushing liquid through the conduit in order to clean the conduit of any deposits or build-up. A plurality of valves are used in order to regulate liquid flow and purge water flow.

Abstract: A mass flow sensor is capable of accurately measuring a mass flow irrespective of changes in the ambient temperature. The mass flow sensor includes at least one heating resistor disposed on a portion of a sensor pipe through which a fluid to be measured flows and a housing for the sensor pipe. The heating resistor and a temperature sensitive resistance constitute a bridge circuit. The temperature sensitive resistance is disposed in the housing. The resistance of the sensor changes in accordance with the change in the temperature of the housing to thereby adjust the change in the resistance of the heating resistor. Further, an improved temperature sensitive matching resistor is suitably used in the mass flow sensor, in which a plurality of temperature sensitive resistances having equal characteristics are integrated.

Abstract: A piston flow meter for measuring gas flow through the flow meter comprising a hollow precision bore flowtube in a vertical orientation, with a movable piston containing a valve assembly for movement in concert with the piston between opposite ends of the flowtube. The valve assembly contains a latching mechanism, preferably a magnetic latch, to provide a positive seal across the piston. The magnetic latch is opened when the piston strikes a spring-loaded stop at the top end of the piston stroke, and is closed at the bottom end of the piston stroke.

Abstract: A flow sensor is disclosed, which has a thin film heater which is formed atop a cavity formed in the substrate, and the thin film heater is formed on its upstream and downstream sides with slits for separating it and temperature sensors from the substrate. The slits have such a small width that a laminar flow of gas can be maintained. In the case where the film heater has a positive resistance temperature coefficient, the thin film heater is disposed such that current flows in a direction of the gas stream, in case when the film heater has a negative temperature coefficient, the thin film heater is disposed such that current flows in a direction perpendicular to the gas stream.

Abstract: A method of quality control for targets intended for use in the sputtering process. A test parameter is established by immersing the target in a tank of liquid, irradiating the target with ultrasonic energy in the Rayleigh frequency range, and integrating the portion of the ultrasonic energy which passes through the target and reflects off the back wall. This test parameter is closely related to the uniformity of a film which may be sputtered from the target onto a substrate.

Abstract: A package burner has a fan rotatably driven at constant speed. Air from the surrounding atmosphere is induced by the fan through an open end of a conduit which guides the air to the fan from which the air is propelled down an outlet passage to mix as combustion air in a chamber with fuel gas from a gas supply nozzle so that flames issue from the chamber. A valve in the conduit or outlet passage can be set to regulate how much air is supplied as combustion air. A fluidic oscillator has an inlet open to the atmosphere and has an outlet open to the interior of the conduit. The observed frequency of the fluidic oscillator is a function of the flow rate of air through the fluidic oscillator and is also a function of the flow rate of air along the conduit. Therefore the measured frequency of the fluidic oscillator can be used to calculate the amount of combustion air being supplied along the conduit in unit time.

Abstract: There is disclosed a micromechanical transducer having only one moving or movable part (1) and a stator (2), the part (1) being movable in relation to the stator and in the form of a flat member which is connected by spring arrangements, such as springs (6), to the stator. The movable part is capable of three-dimensional movement to implement a deflection.

Abstract: A mass flow sensor detects the intensity of a media flow. The mass flow sensor includes a measurement chip, with a dielectric membrane and a frame of monocrystalline silicon. At least one heater is arranged on the membrane. The measurement chip is installed in the in-flow channel of a housing. By means of the structure of the housing, contamination of the measurement chip is reduced, thermal equalization with the media flow is improved, the resistance of the sensor to sudden pressure variations is increased, and the dielectric contacts are improved.