Abstract: A valve comprising a controller; a heater; and two temperature transducers. The controller sends a close signal to the actuator and records a first temperature signal from the first temperature transducer, then controls the heater to attain a first temperature set point at the second temperature transducer. The controller records a time or an amount of energy required to attain the first temperature set point, then sends an open signal. The controller records a second temperature, controls the heater to attain a second set point at the second transducer, and records a time or an energy required to attain the second temperature set point. The controller classifies a fluid inside based on the first value and a flow rate of the fluid through the fluid path based on the second value.

Abstract: The present invention provides a low-cost intelligent integrated spraying pressure and flow detection device and method. The low-cost intelligent integrated spraying pressure and flow detection device includes an intelligent integrated pressure and flow detection device, a control unit and a calibration system. The intelligent integrated pressure and flow detection device is a device which integrates a pressure detection unit and a flow detection unit and is configured to detect pressure and flow. The control unit is connected to the intelligent integrated pressure and flow detection device and the calibration system. The calibration system is configured to simulate a working condition of the intelligent integrated pressure and flow detection device during field work.

Abstract: A device for detecting air flows includes an air line channeling an air flow. The line (for example a tube) includes at least one first temperature sensor and one second temperature sensor (inside the tube). At least one of the sensors is subjected to periodic temperature fluctuations controlled by at least one heating device, such as a variable-current power source dedicated to the sensor.

Abstract: A gas meter device of the present invention includes an inlet into which a fluid flows, and an outlet from which the fluid flows out, and is configured to derive a flow value of the fluid flowing from the inlet to the outlet.

Abstract: An anemometer and method for analyzing fluid flow is described. In one embodiment, a transistor sensor is heated by applying power to cause its base-emitter junction to rise from an ambient first temperature to a second temperature. The power is removed, and the Vbe is measured at intervals as the junction cools. The Vbe equates to a temperature of the junction. The temperature exponentially decreases, and the time constant of the decay corresponds to the fluid flow velocity. A best fit curve analysis is performed on the temperature decay curve, and the time constant of the exponential decay is derived by a data processor. A transfer function correlates the time constant to the fluid flow velocity. The transistor is thermally coupled to a metal rod heat sink extending from the package, and the characteristics of the rod are controlled to adjust the performance of the anemometer.

Abstract: In a thermal sensor. a capacitor voltage of a capacitor is compared with a reference voltage, and an output voltage is generated based on the comparison. The output voltage has a pulse density indicative of a temperature detected by the thermal sensor. The capacitor is charged or discharged using at least one of a first current signal or a second current signal based on a logic level of the output voltage. The first current signal is a temperature-independent signal, and the second current signal is a temperature-dependent signal dependent on the temperature detected by the thermal sensor. In some embodiments, a clock rate of a clock signal is varied in accordance with the detected temperature to control a timing operation for supplying the first current signal to the capacitor and/or the reference voltage is varied in accordance with the detected temperature.

Abstract: A respiration monitoring system includes a thermoelectric generator that may be mounted within a mask enclosure or free-standing, covering all or part of the nose and/or mouth of a subject. A first temperature sensor is attached to the thermoelectric generator for measuring the subject's breath. A power controller develops a difference between a preset temperature and the subject's breath temperature that is then inserted into a feedback error signal and then into a power controller which regulates the power to the thermoelectric generator to maintain a preset temperature.

Abstract: The design and manufacture method of a silicon mass flow sensor made with silicon Micromachining MEMS, Micro Electro Mechanical Systems) process for applications of gas flow measurement with highly humidified or liquid vapors is disclosed in the present invention. The said silicon mass flow sensor operates with an embedded heater and an adjacent control temperature sensor beneath the integrated calorimetric and thermal dissipative sensing thermistors. When the condensation takes place at the surface of the said silicon mass flow sensor, the embedded heater shall be turned on to elevate the temperature of the supporting membrane or substrate for the sensing thermistors. The elevated temperature shall be adjusted to above the vaporization temperature with the feedback data of the adjacent temperature sensor such that the surface condensation due to the presence of the liquid vapors in a gas flow can be effectively eliminated.

Abstract: The invention relates to a miniaturised sensor having a heating element, and to an associated production method. The sensor includes a substrate, a cavity and a heat-insulating structure suspended above the cavity by areas connecting to the substrate. The heat-insulating structure includes at least two bridges extending above the cavity, the heating element being supported by said bridges, extending transversely thereto.

Abstract: The invention provides a probe for a flowmeter which can be employed in various flow measuring devices utilizing semiconductor or ceramic thermistors. The invention comprises an apparatus for determining the fluid flow rate of a liquid passing through a conduit made of a material having a low thermal conductivity, comprising a probe disposed at least partially inside the wall of the conduit, part of the probe being substantially aligned with an inner surface of the wall, the probe being operationally connected to a control and display unit. The probe comprising a printed circuit board (PCB) on which at least two thermistors are mounted; an upstream thermistor serving for baseline measurements and a spaced apart downstream self-heated thermistor. The control and display unit repeatedly measuring the electrical resistance of the thermistors to generate signals which are electronically processed by the control and display unit to indicate flow rates.

Abstract: Flow-meter device (1) for the measurement of a flow of at least one fluid through a measurement chamber (3) arranged in a housing (2) of the flow-meter device (1). The flow-meter device (1) has at least one rotating element (4) that is mounted so that it can rotate and can be rotated by fluid flowing through the measurement chamber (3) and at least two rotation sensors (5) for the measurement of the rotation of the rotating element (4). The two rotation sensors (5) are arranged on a common sensor carrier (6) and another temperature sensor (7) is also arranged on the common sensor carrier (6).

Abstract: A detecting apparatus for detecting operation of a fan, includes a first current module disposed at an airflow path of the fan, a second current module insulated from the airflow, and an indicating module for giving an indicating signal, having a LED, and a transistor. The first and second current modules being mirror-images of each other. When the fan does not operate, the first and second current modules operate the same. The transistor of the indicating module is turned off, and the LED to be lit. When the fan operates, current flow of the first and second modules are different from each other producing a voltage greater than zero, the transistor of the indicating module is turned on, and the LED does not light.

Abstract: Formation of a structure with through-holes includes attaching two sub-structures to one another. The resulting structure may be used in a sub-assembly for various types of micro components and may serve as a lid or base of a housing that encapsulates one or more micro components. The techniques may provide greater flexibility in the shape of the through-holes and may reduce costs compared with other known techniques.

Abstract: A temperature compensating fluid flow sensing system is provided that comprises a resistance-based sensor element that is included in a constant voltage anemometer circuit configured to establish and maintain a command voltage across the first sensor element and to provide a constant voltage anemometer (CVA) output voltage corresponding to the resistance change in the first sensor element due to heat transfer between the first sensor element and the fluid. A controller is configured to establish the command voltage based on a desired overheat across the sensor and an actual overheat across the first sensor element. A power dissipation (PDR) module is configured to determine at least one fluid flow parameter and an actual overheat value based at least in part on the CVA output voltage and to transmit to the controller the actual overheat for use by the controller in updating the command voltage.

Abstract: In a preferred embodiment, a thermal mass flow meter is provided with: a pipe arrangement that allows a fluid to flow therein, a chip-type heat-generating element that is anchored on the surface on the periphery of the pipe arrangement and used for heating the fluid in the pipe arrangement, and paired chip-type temperature sensors that are anchored at positions on the upstream side and the downstream side of the heat-generating element with the same distance apart therefrom, on the surface of the pipe arrangement, and formed as members separated from the heat-generating element. With respect to the heat-generating element and the paired temperature sensors, convex portions thereof on a side opposite to the side to be anchored onto the pipe arrangement are housed in a concave of a printed-circuit board, and terminals of the heat-generating element and the paired temperature sensors are connected to the wiring layer of the printed-circuit board, and subsequently secured to the printed-circuit board.

Abstract: A fluid flow rate sensor includes a detection circuit which generates a first signal corresponding to an output voltage of a bridge circuit, and a second signal corresponding to a fluid temperature. A control module can more accurately and quickly determine the fluid flow rate based on the first signal, the second signal and a look-up table. The look-up table includes a plurality of curves plotted according to data, indicating relationship among the fluid temperature, the output voltage and the fluid flow rate. The fluid flow rate sensor is inherently temperature compensated and has a shorter response time.

Abstract: A method of monitoring fluid flow uses an optical fiber having a heatable coating. The fiber is disposed within flowing fluid, and the heatable coating heated so that heat is transferred from the coating to the fluid. Optical measurements of the temperature of the heatable coating are made, where the temperature of the heatable coating depends on the flow velocity of the flowing fluid, and the temperature measurement is used to derive information about the flow. The coating may be an electrically resistive layer on the outer surface of the fiber, that is heated by passing electric current through it. This allows distributed flow measurements to be made. Alternatively, discrete measurements can be made if the coating is provided as a thin film layer on an end facet of the fiber. The coating is heated by directing light at a wavelength absorbed by the thin film material along the fiber.

Abstract: A mass airflow sensor is disclosed that includes a heating element comprising an upstream side and a downstream side. Two resistive temperature sensors are placed on each side of the heating element and assuming mass air/liquid flows in a direction from left to right. The resistors are configured electrically in a Wheatstone bridge configuration. A regulated voltage is applied across the mass flow sensing, Wheatstone bridge. The regulated voltage is set high enough to produce self-heating effects on the sensing bridge. The central heating element will also be heated. As mass air/liquid flows across the temperature sensors and the heating element, the upstream (RU1 and RU2) resistors are cooled and the downstream (RD1 and RD2) resistors are heated. The resistance in the resistive temperature sensors changes with temperature creating a differential voltage signal proportional to the regulated voltage applied to the sensing Wheatstone bridge and rate of mass air/liquid flow.

Abstract: A channel substrate containing at least one channel for a fluid is provided. A sensor substrate carrying a thermal flow sensor is arranged adjacent to the channel substrate. The flow sensor contains at least one temperature sensor and at least one heater, which are integrated on the sensor substrate. The heater and the temperature sensor are in thermal contact with the channel in the channel substrate. This arrangement allows to measure the flow of the fluid in the channel, which provides an improved monitoring and control. The sensor substrate can have contact pads connected to bond wires or, using flip-chip technology, the contact pads can be connected to circuit paths to the channel substrate.

Abstract: A device for measuring a volume flow, especially a tidal volume flow sensor, with a flow channel (1) and with a sensor element (6) arranged within the flow channel (1), is shown and described. The task of providing such a device, in which the sensor signal, which is generated by sensor elements arranged in the flow channel, remains as free as possible from distortions during the transmission to an evaluating unit, is accomplished by providing an internal circuit (3), which is arranged within the flow channel (1) and includes the sensor element (6). An external circuit (7) is arranged outside the flow channel (1). The external circuit (7) is designed for contactless, inductive coupling with the internal circuit (3) for supplying same with energy and for reading.

Abstract: A thermo-anemometer-type fluid flow rate sensor design and a method for its operation that overcome the response time limitations of prior known fluid flow rate sensors is disclosed. The fluid flow rate sensor includes a probe having a detection module adapted to change condition in response to the presence of the flow of the fluid, a control module that is electrically connected to the probe that monitors the condition of the detection module over time (e.g., a temperature), determines a rate of change of that condition over time, and generates an output that is indicative of the rate of flow of the fluid, and a I/O module connected to the control module to provide a means for communicating the output of the control module to another device or a user.

Abstract: In a preferred embodiment, a thermal mass flow meter is provided with: a pipe arrangement that allows a fluid to flow therein, a chip-type heat-generating element that is anchored on the surface on the periphery of the pipe arrangement and used for heating the fluid in the pipe arrangement, and paired chip-type temperature sensors that are anchored at positions on the upstream side and the downstream side of the heat-generating element with the same distance apart therefrom, on the surface of the pipe arrangement, and formed as members separated from the heat-generating element. With respect to the heat-generating element and the paired temperature sensors, convex portions thereof on a side opposite to the side to be anchored onto the pipe arrangement are housed in a concave of a printed-circuit board, and terminals of the heat-generating element and the paired temperature sensors are connected to the wiring layer of the printed-circuit board, and subsequently secured to the printed-circuit board.

Abstract: A temperature compensating fluid flow sensing system is provided that comprises a resistance-based sensor element that is included in a constant voltage anemometer circuit configured to establish and maintain a command voltage across the first sensor element and to provide a CVA output voltage corresponding to the resistance change in the first sensor element due to heat transfer between the first sensor element and the fluid. A controller is configured to establish the command voltage based on a desired overheat across the sensor and an actual overheat across the first sensor element. A PDR module is configured to determine at least one fluid flow parameter and an actual overheat value based at least in part on the CVA output voltage and to transmit to the controller the actual overheat for use by the controller in updating the command voltage.

Abstract: Firstly, a supporting frame is produced, whose opening is spanned by an auxiliary layer flush on one side. Following the production of microstructures, flat parts or membranes on the common plane defined by the auxiliary layer and the supporting frame, the auxiliary layer is removed, preferably by etching. In a preferred application, the self-supporting microstructures produced in accordance with the method of the invention are used as electrically heatable resistance grids in a device for measuring weak gas flows.

Abstract: An air meter is provided which enables the improvement of accuracy of internal reference voltages with few IC terminals. A band gap reference power supply circuit 6 supplies an internal reference voltage to a characteristic adjusting circuit 4 and an internal reference voltage VINT to a multiplier circuit 5. the band gap reference power supply circuit 6 comprises a temperature current generating circuit 21 for generating a current proportional to a temperature, a current mirror circuit for duplicating the current of the temperature current generating circuit 21, a reference voltage generating circuit 23 through which the current duplicated by the current mirror circuit 22 is caused to be flowed to generate the internal reference voltage ES, and a reference voltage generating circuit 24 through which the current duplicated by the current mirror circuit 22 is caused to be flowed to generate the internal reference voltage VINT.

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 sensor for measuring a flow speed of a fluid medium includes a housing with a carrier membrane disposed in the housing and being essentially in a form of a vane having a circumference and at least one edge region. Holding elements are arranged over a portion of the circumference connecting the vane to the housing so that only the at least one edge region of the carrier membrane is subjected to mechanical stress caused by the housing. An electrically conductive track with feed lines is installed on the carrier membrane in a region of a neutral fiber for the carrier membrane which does not experience a mechanical strain when the carrier membrane is bent. The electrically conductive track is adapted for being heated relative to the environment by an electrical current flowing through the electrically conductive track.

Abstract: A sensor chip having at least upstream from the sensor region, at least one potential surface that, by electrical interaction with the contaminants in the flowing medium, prevents precipitation in the sensor region.

Abstract: A sensor chip exposed to a flowing medium is provided with an additional heater situated upstream and at a definite distance from the sensor area, resulting in the impurities in the flowing medium being deposited in the area of the additional heater, and in the impurities being unable to reach the sensor area.

Abstract: A thermal anemometer that separates sensor heating from sensor temperature measurement through a switched sampling technique. This approach demonstrates several advantages over the more typical circuitry employing a bridge, which simultaneously heats the sensor and senses the ambient and velocity sensor temperature. In a thermal anemometer in accordance with the present invention, sensor temperature is determined by sampled measurement of its resistance. Sensor temperature is controlled by varying the voltage applied to the sensor with an error value determined by the difference between actual sensor resistance and the desired resistance.

Abstract: A sensor for determining flow rate of a fluid includes a thermistor inserted into a volume through which the fluid flows. The thermistor cycles between its zero-power mode and its self-heated mode. In the zero-power mode, the thermistor is used to determine the ambient temperature of the fluid. In the self-heated mode, the thermistor is used to determine the amount of heat removed by the fluid. The ambient temperature of the fluid, the amount of heat removed by the fluid, and the thermal properties of the fluid are then utilized to determine the flow rate of the fluid.

Abstract: An air meter is provided which enables the improvement of accuracy of internal reference voltages with few IC terminals. A band gap reference power supply circuit 6 supplies an internal reference voltage to a characteristic adjusting circuit 4 and an internal reference voltage VINT to a multiplier circuit 5. the band gap reference power supply circuit 6 comprises a temperature current generating circuit 21 for generating a current proportional to a temperature, a current mirror circuit for duplicating the current of the temperature current generating circuit 21, a reference voltage generating circuit 23 through which the current duplicated by the current mirror circuit 22 is caused to be flowed to generate the internal reference voltage ES, and a reference voltage generating circuit 24 through which the current duplicated by the current mirror circuit 22 is caused to be flowed to generate the internal reference voltage VINT.

Abstract: An air meter is provided which enables the improvement of accuracy of internal reference voltages with few IC terminals. A band gap reference power supply circuit 6 supplies an internal reference voltage to a characteristic adjusting circuit 4 and an internal reference voltage VINT to a multiplier circuit 5. the band gap reference power supply circuit 6 comprises a temperature current generating circuit 21 for generating a current proportional to a temperature, a current mirror circuit for duplicating the current of the temperature current generating circuit 21, a reference voltage generating circuit 23 through which the current duplicated by the current mirror circuit 22 is caused to be flowed to generate the internal reference voltage ES, and a reference voltage generating circuit 24 through which the current duplicated by the current mirror circuit 22 is caused to be flowed to generate the internal reference voltage VINT.

Abstract: A thermal dispersion switch/transmitter for determining flow rate and liquid level in a non-contacting apparatus. A special preparation of one or more small spots in the outside surface of the wall of the conduit, standpipe or container enables one or more thermally sensitive elements to reside very close to the fluid on the opposite side of the wall. A temperature sensor is formed of a raster pattern electrical conductor deposited on a thin, electrically insulative, thermally conductive flat chip. One temperature sensor is time-shared and is periodically self heated and functions as the reference as well as the active or heated sensor of the invention. One alternative is to employ two temperature sensors, one being a reference sensor and the other being the active sensor. An alternative embodiment employs the same construction of one or more small, very thin membrane surfaces to which multiple detectors are mounted inside a probe inserted into the conduit.

Abstract: An improved mass flow sensor interface (“MFSI”) circuit and method are disclosed for sensing and measuring mass flow rate of a gas and provide an output voltage proportional to the mass flow rate in a mass flow controller. The improved MFSI circuit of the present invention includes upstream and downstream mass flow sense elements a precision current source to drive the circuit. The circuit further includes an operational amplifier to sum the voltage upstream of the upstream sense element with the voltage downstream of the downstream sense element. A reference voltage is electrically connected to the positive node of the operational amplifier. An upstream shunting resistor and a downstream shunting resistor share a common junction at the negative node of the operational amplifier and are electrically connected in parallel to the upstream and downstream mass flow sense elements.

Abstract: A system for detecting the level of fluid in a fluid containing vessel. The system includes a device for applying energy to a selected location on the vessel. A sensor in proximity to the location detects the energy level at the location during first and second intervals. A memory device stores data representative of the energy detected by the sensor at each interval, and a logic circuit compares the amount of energy of the first interval to that of the second. Data corresponding to the level of fluid in the vessel may be displayed locally or signaled to remote data receiving and display devices, as appropriate.

Abstract: A method and device, employing positive-temperature-coefficient material, for sensing plural properties of a fluid, such as temperature and flow rate. Can be used in a wind gauge or in a device for sensing position of mechanical elements such as valve diaphragms. Single sensor device, with energy and ohmic resistors, produces two voltages which completely characterize temperature and flow rate of fluid under study.

Abstract: A heating resistor type air flow rate measuring apparatus is provided with a couple of heating resistors placed at the positions where those resistors may interfere thermally each other with respect to an air flow, and a couple of driving circuits for driving those heating resistors. The air flow rate signal is obtained by calculating the difference between the output signals of a couple of heating resistors in terms of heat radiation rate effected by an air flow, and adding the difference value onto the output signal of one of heating resistors.

Abstract: In a ratiometric output type air flow meter with a heat generating resistor, a ratiometric circuit is provided with a divider circuit which is constituted by invariable resistors and divides an external reference voltage Vref and a multiplier circuit. The invariable resistor is grounded, via the invariable resistor. To one of input terminals of the multiplier circuit an output signal V0 of an operational amplifier is inputted, to the other input terminal of the multiplier circuit voltage Vex divided by the invariable resistors is inputted, and the output signal Vout of the multiplier circuit is outputted to an engine control unit. A correction use resistor is connected at the junction of the invariable resistor and a current detection resistor, and is grounded via a ground wiring resistance.

Abstract: An air meter is provided which enables the improvement of accuracy of internal reference voltages with few IC terminals. A band gap reference power supply circuit 6 supplies an internal reference voltage to a characteristic adjusting circuit 4 and an internal reference voltage VINT to a multiplier circuit 5. The band gap reference power supply circuit 6 comprises a temperature current generating circuit 21 for generating a current proportional to a temperature, a current mirror circuit for duplicating the current of the temperature current generating circuit 21, a reference voltage generating circuit 23 through which the current duplicated by the current mirror circuit 22 is caused to be flowed to generate the internal reference voltage ES, and a reference voltage generating circuit 24 through which the current duplicated by the current mirror circuit 22 is caused to be flowed to generate the internal reference voltage VINT.

Abstract: A thermal dispersion switch/transmitter for determining flow rate and liquid level in a non-contacting apparatus. A special preparation of one or more small spots in the outside surface of the wall of the conduit, standpipe or container enables one or more thermally sensitive elements to reside very close to the fluid on the opposite side of the wall. A temperature sensor is formed of a raster pattern electrical conductor deposited on a thin, electrically insulative, thermally conductive flat chip. One temperature sensor is time-shared and is periodically self heated and functions as the reference as well as the active or heated sensor of the invention. One alternative is to employ two temperature sensors, one being a reference sensor and the other being the active sensor. An alternative embodiment employs the same construction of one or more small, very thin membrane surfaces to which multiple detectors are mounted inside a probe inserted into the conduit.