Abstract: A thermal flow sensor has a first, second and third substrate, each having a first side and a second opposite side. The first substrate is connected to the second substrate such that the second side of the first substrate abuts the first side of the second substrate. The third substrate is connected to the second substrate such that the second side of the second substrate abuts the first side of the third substrate. The first, second and third substrate form a multi-layer body structure having at least one edge extending between a first side of the first substrate and the second side of the third substrate. The second substrate has a groove formed therein so as to form a conduit bounded by the second substrate and the second side of the first substrate and the first side of the third substrate. The conduit has an inlet opening and an outlet opening that are formed in the at least one edge.

Abstract: A measurement pickup includes at least four measuring tubes for conveying media to be measured. Each measuring tube has a first in-/outlet end and a second in-/outlet end. During operation, the measuring tubes vibrate, at least at times, especially simultaneously. The measurement pickup further includes an electromechanical exciter mechanism causing the measuring tube to vibrate, as well as a sensor arrangement reacting at least to local vibrations of the measuring tubes for producing at least one measurement signal influenced by vibrations of the measuring tubes.

Abstract: An ultrasonic flowmeter includes a transmission/reception means provided in a flow path for performing transmission/reception using a state change of fluid; repetition means for repeating the transmission/reception; time measurement means for measuring a time of propagation repeated by the repetition means; flow rate detection means for detecting a flow rate based on a value of the time measurement means; and number-of-times change means for changing to a predetermined number of repetition times. With such a structure, an influence caused by a variation of a flow can be suppressed by changing the number of repetition times so as to be suitable for a variation. As a result, reliable flow rate measurement with a high accuracy can be achieved.

Abstract: A waste-material entry prevention member arranged upstream of a flow sensor is a rod- or plate-like member protruding halfway across the cross-section of a flow passage. Hence, vortexes or energy of the vortexes produced in fluid flowing by the waste-material entry prevention member is diffused by a stream of the fluid passing through a space left between the waste-material entry prevention member and the wall surface of the flow passage which the waste-material entry prevention member faces. Thus, production of vortexes is held down. Further, by making the flow sensor generate heat or heating the flow sensor, thermophoresis of the fluid is caused near the surface of the flow sensor. By this, particles contained in the fluid are prevented from accumulating on the flow sensor.

Abstract: Performance of mass flow controller may be vulnerable to pressure transients in a flow path to which the controller is coupled for the purpose of controlling the fluid flow. A system and method are provided for reducing or eliminate performance degradations, instabilities, and/or inaccuracies of a mass flow controller caused by changes in the pressure environment. In particular, a method and system are provided for compensating for pressure transients in the pressure environment of a flow path and mass flow controller.

Abstract: The transducer (1) has at least one at least temporarily vibrating flow tube (101) of predeterminable lumen for conducting a fluid. The flow tube (101) communicates with a connected pipe via an inlet tube section (103), ending in an inlet end, and an outlet tube section (104), ending in an outlet end, and in operation performs flexural vibrations about an axis of vibration joining the inlet and outlet ends. The flow tube (101) has at least one arcuate tube section (101c) of predeterminable three-dimensional shape which adjoins a straight tube segment (101a) on the inlet side and a straight tube segment (101b) on the outlet side. At least one stiffening element (111, 112) is fixed directly on or in close proximity to the arcuate tube segment (101c) to stabilize the three-dimensional shape.

Abstract: An apparatus 10,110 is provided that measures the speed of sound or acoustic disturbances propagating in a fluid or mixture having entrained gas/air to determine the gas volume fraction of the flow 12 propagating through a pipe 14. The apparatus includes an array of pressure sensors disposed axially along the length of the pipe. The apparatus measures the speed of sound propagating through the fluid to determine the gas volume fraction of the mixture using adaptive array processing techniques to define an acoustic ridge in the k-? plane. The slope of the acoustic ridge 61 defines the speed of sound propagating through the fluid in the pipe.

Abstract: A heating resistor type flow measuring device comprising a housing having a support part provided between a frame body and a connector and connected to the mounting part of a fluid passage, a flow rate detection element held on the frame body side of the housing, and an electronic circuit held on the housing and connected electrically to the flow rate detection element and the connector, wherein the electronic circuit is held on the frame body side of the housing and positioned in the fluid passage, a member with the rigidity higher than the material of the main structural member of the housing is formed integrally with the support part, the housing is fixed to the fluid passage through the member with high rigidity. A metal plate is inserted into the support part so as to increase rigidity.

Abstract: A split-flow-type flow sensor apparatus includes a main flow passage and a bypass flow passage, wherein a thermal flow sensor is placed on the wall face of the bypass flow passage. A first rectification member is placed upstream from a diversion part to the bypass flow passage in the main flow passage, and a second rectification member is placed upstream from the thermal flow sensor in the bypass flow passage. A bypass flow passage module is inserted into an opening formed on a side of a main flow passage module. The side opening of the main flow passage module is sealed and an entrance and an exit of the bypass flow passage are positioned in the main flow passage.

Abstract: A method and system for measuring the flow rate of a liquid or gas within a flow channel utilizing a centrally located excitation source and a plurality of sensors. The excitation source is comprised of a heating element coupled with an alternating current generator. Of the plurality of sensors, at least one of the sensors is located in a position upstream of the excitation source location, and additionally a second of the plurality of sensors is located in a position downstream of the excitation source. Instantaneous fluid flow rate is calculated utilizing a high gain differential amplifier electrically coupled to the sensors, wherein the convectively induced inductive gradient of the flowing fluid is compared to the symmetrical zero flow induction gradient. Following such a comparison, a voltage signal proportional to the flow of fluid within the channel is derived.

Abstract: A magnetoinductive flowmeter encompasses a ceramic measuring tube as a conduit for a medium whose flow rate is to be measured, and a measuring electrode featuring a cermet body. The measuring tube is mounted in the wall of the measuring tube with its side that faces the medium conductively or capacitively connecting to the medium while its side facing away from the medium connects to a measuring line. The cross-sectional surface area of the cermet body is larger at its end facing the medium than at its other end facing away from the medium. The result is a measuring electrode that fully meets the respective requirements at either end notwithstanding minimized material consumption in making the electrode. A method for producing a measuring tube for the flowmeter is also disclosed.

Abstract: A housing for a sensor to prevent condensate from collecting in the sensor. The housing includes a deflector to channel condensate forming in the housing away from the sensor. A notch is provided at the base of the sensor to ensure any condensate forming on the sensor itself does not collect at the sensor base. Further the interior of the housing is roughened and treated with an antifogging agent to ensure any condensate falls continuously so droplets do not form.

Abstract: A process meter for measuring at least one physical process variable of a medium stored in a container or flowing in a line, comprising: a transducer including a sensor arrangement providing measurement signals (s1, s2), said sensor arrangement having: at least a first sensor providing at least a first measurement signal (s1) in response to the physical process variable being measured, particularly to changes in the process variable, and at least a first temperature sensor mounted in said transducer for locally sensing a first temperature, T1, in the transducer, and by means of said at least one temperature sensor, at least a first temperature measurement signal (?1) representing the first temperature, T1, in said transducer; and meter electronics which, using at least said first measurement signal (s1) and a first correction value (K1) for the at least first measurement signal (s1), derive at least one measured value (X) currently representing the physical variable, wherein: during operation, said meter elec

Abstract: A thermal flow sensor has a first, second and third substrate, each having a first side and a second opposite side. The first substrate is connected to the second substrate such that the second side of the first substrate abuts the first side of the second substrate. The third substrate is connected to the second substrate such that the second side of the second substrate abuts the first side of the third substrate. The second substrate has a groove formed therein so as to form a conduit bounded by the second substrate and the second side of the first substrate and the first side of the third substrate. A heater is disposed on the first side of the first substrate opposed to the conduit. A first temperature sensor is disposed on the first side of the first substrate opposed to the conduit. A second temperature sensor is disposed on the first side of the first substrate opposed to the conduit.

Abstract: Measurements are obtained by a computing unit based on an output Vh from an indirectly-heated constant-temperature controlling flow rate measuring section (16) and an output Vout from a two-constant-point temperature difference detecting flow rate measuring sections (18a, 18b). In the flow rate measuring section (16), a heating element (163) is feedback-controlled based on a detected temperature by a heat sensing element (162) to obtain an output Vh based on the feedback-controlled condition. An output Vout is obtained from flow rate measuring sections (18a, 18b) based on the detected temperature difference between a heat sensing element (182) disposed on the liquid-flow-direction upstream side of the flow rate measuring section (16) and a temperature sensing element disposed on the downstream side.

Abstract: A procedure for determination of flow and fraction of fluids includes the steps of: determination of Spin-Lattice relaxation times to be measured; assignment of radiofrequency pulse sequences corresponding to each of the fluids to be measured and with the fluid flow; application of a radiofrequency pulse sequence to a first coil; application of a second radiofrequency pulse sequence to the first coil; and application of a third radiofrequency pulse sequence to a second coil.

Abstract: The invention relates to a method of acoustically monitoring the course of a process, in which method the amplitude difference and/or the intensity value of sound are/is measured during the process, and the amplitudes and/or the intensity values of the sound and/or the vibrations are measured continuously or with an adjustable frequency by means of a sound and/or vibration sensor (4), such as a piezoelectric transducer (12), during the entire process or part of the process and are compared mutually and/or with a predetermined threshold value and/or reference value and/or reference pattern for the purpose of drawing, on the basis thereof, conclusions in relation to the progress and/or the course of the process and/or the presence of disturbances and/or deviations in the course of the process.

Abstract: In accordance with the teachings of the present invention, a system and method for regulating bridge voltage in a discrete-time hot-wire anemometer is provided. In a particular embodiment, the hot-wire anemometer includes a bridge circuit including a hot-wire resistor, first and second input terminals, and first and second output terminals, the hot-wire resistor having a resistance dependent at least in part on an airflow past the hot-wire resistor. The hot-wire anemometer further includes a first operational amplifier coupled to the output terminals of the bridge circuit, the first operational amplifier operable to generate an output signal in response to a voltage differential across the first and second output terminals of the bridge circuit, and a second operational amplifier operable to generate an output signal in response to the output signal of the first operational amplifier and to a discontinuous time control signal.

Abstract: The present invention relates to a flowmeter suitable for a micro flow sensor. The flowmeter of the present invention comprises a resistive heater to be inserted into a fluid, AC power with a first frequency supplied to the resistive heater to periodically heat the resistive heater, a signal processing unit for detecting a first signal from the resistive heater in relation to a temperature variation of the resistive heater by the AC power, and obtaining a phase lag of the first signal relative to the heat generation in the resistive heater, and an operation unit for calculating a flow rate based on the obtained phage lag. According to the present invention, the flowmeter of the present invention has a wide measurement range and high measurement accuracy with a simple structure.

Abstract: The flow detecting elements are provided at the sub-passage for making the part of fluid to be measured (gas) flow. The wall of the sub-passage contains a leak hole (through hole) to drain a liquid having entered and accumulated inside the sub-passage. A protrusion for generating a dynamic pressure on the opening is arranged close to the opening of the leak hole on the external surface of the sub-passage. Alternatively, a protrusion located upstream from the leak hole is formed on the inner wall surface of the sub-passage. The former protrusion generates a dynamic pressure in response to the flow velocity of the gas flowing along the external surface of the sub-passage. The latter protrusion produces a separation flow area for separating the flow from the internal surface of the sub-passage (close to the leak hole), whereby the pressure of the separation floe area is reduced.