Abstract: A flow sensor includes a substrate, an electrical insulating film, and a flow velocity detection mechanism. In the substrate, a diaphragm portion having a first surface in contact with a measurement target fluid and a thick fixing portion surrounding the diaphragm portion are integrally formed. The electrical insulating film is formed on a second surface of the diaphragm portion which is on a side opposite to the first surface. The flow velocity detection mechanism is arranged on the electrical insulating film. A method of manufacturing a flow sensor is also disclosed.

Abstract: A sensor for measuring the flow velocity of gases. The sensor includes a printed circuit board (1) having an opening (2) formed therein. A pair of first contact elements are disposed on opposing sides of the opening on an upper side of the circuit board (1), and a pair of second contact elements are disposed on opposing sides of the opening on a lower side of the circuit board (1). A first wire (4) with end portions respectively connected to the first contact elements extends across the opening (2) on the upper side of the circuit board (1). A second wire (10) with end portions respectively connected to the second contact elements extends across the opening (2) on the lower side of the circuit board (1).

Abstract: A flow sensor system is provided for measuring the rate of flow of a fluid in a flow channel that is configured to contain the flow. A substrate may be disposed in the flow channel, and a plurality of transducers may be disposed on the substrate in the flow channel. The substrate may also provide a plurality of paths, and each path may conduct a signal. The transducers may be configured to respond to the fluid flow by modifying the signals in relation to the flow. The transducers may be arranged with at least one of the transducers disposed closer to a central longitudinal axis of the flow channel than at least one other transducer. A signal processor may be coupled to at least two of the signals, and the signal processor may calculate the rate of flow of the fluid as a function of the at least two signals.

Abstract: In a flow sensor, a heater is provided in the middle of an insulation thin film stretched above a gap on a substrate. Temperature measuring elements, which in some embodiments are thermopiles, are provided on both sides of the same, and an ambient temperature measuring resistive element is provided on the top surface of the silicon substrate. The thermopiles in some embodiments are made of polysilicon and aluminum, and in some embodiments the polysilicon is doped with phosphorus (P). In some embodiments, the amount of phosphorus is determined such that temperature characteristics of the thermopiles and have an absolute value substantially equal to that of temperature characteristics attributable to factors other than the thermopiles and have a (positive or negative) sign opposite to that of the latter. Thus, the temperature characteristics of the thermopiles cancel the temperature characteristics attributable to factors other than the thermopiles.

Abstract: A heat generation type flow sensor of an enhanced output sensitivity which is destined for use, for example, as an air flow sensor employed in an engine control system of a motor vehicle.

Abstract: A mass flow sensor to be mounted within a duct and measures the mass flow of a fluid stream moving through the duct. The sensor is an elongated thin quartz substrate having a plurality of platinum strips extending in a parallel relationship on the strip, with certain of the strips being resistors connected to an excitation voltage. The resistors form the legs of a Wheatstone bridge. The resistors are spaced a sufficient distance inwardly from the leading and trailing edges of the substrate to lie within the velocity recovery region so that the measured flow is the same as the actual upstream flow. The resistor strips extend at least half-way through the fluid stream to include a substantial part of the velocity profile of the stream. Certain of the resistors detect a change in temperature as the fluid stream moves across the substrate to provide an output signal from the Wheatstone bridge which is representative of the fluid flow.

Abstract: A thermosensitive flow rate sensor includes a detecting element, in which a heating element and a fluid temperature detector are formed so as to be separated from each other on a surface of a flat substrate and a flow rate detection diaphragm is formed under a region where the heating element is formed, and a support having a recess portion, the detecting element being housed inside the recess portion such that a surface of the detecting element is positioned generally in a common plane with a surface of the support and such that a direction of alignment of the heating element and the fluid temperature detector is perpendicular to a direction of flow of a fluid being measured, and a groove being formed in the support so as to pass under a region where the fluid temperature detector is formed in the direction of flow of the fluid being measured.

Abstract: A frame-shaped peripheral wall member is disposed on a holder so as to surround an electrical connection portion between a terminal and a flow rate detecting element, a bottom surface of the peripheral wall member being secured by bonding to the holder and the flow rate detecting element by a heat-curing addition-reaction silicone adhesive. A heat-curing addition-reaction gel containing a fluorine resin as a major constituent is injected and cured inside the peripheral wall member so as to embed the electrical connection portion.

Abstract: A thermo-sensitive flow rate sensor that comprises a plate-like substrate, a part of which is removed so that a space is provided therein, a diaphragm portion formed like a thin layer above the space in such a manner as to be integral with the plate-like substrate, and a heating element constituted by a thermo-sensitive electrically resistant film formed on the diaphragm. Plural holes penetrating the diaphragm portion are bored in an outer peripheral portion of the heating element. Each of the plurality of holes is shaped in such a way as to have obtuse corner portions or to have substantially no corner portions. The thermo-sensitive flow rate sensor measures the flow rate of a fluid, which is to be measured, according to an amount of heat transferred to the fluid from a part heated by energizing the heating element.

Abstract: Construction of a micro-thermocouple sensor designed to be incorporated in a mass flow meter for the circulation of gaseous fluids, includes of the following steps: depositing an insulating layer of several microns by electron gun on the sensor tube, then depositing the components of the thermocouple, by the electron gun, through the nickel masks, at a residual pressure lower than 10−6 torr, at a thickness of several thousand Angstroms, annealing of the capillary tube for one hour, then the mounting of a heating element on the capillary tube treated in this manner.

Abstract: A thermal airflow sensor is made highly resistant to thermal stresses due to cold-heat cycles, highly reliable even in the presence of corrosive gases, and capable of low dispersion of output characteristics. The thermal airflow sensor has a semiconductor sensor element in a dent formed on a ceramic laminated board on which a control circuit and a metallic film are formed. The laminated board area at which the semiconductor sensor element is electrically connected to the laminated board is covered with epoxy resin. The part covered with epoxy resin is placed in the air passage.

Abstract: When a micro-heater heats fluid using an external driving current, an upstream thermopile 8 detects the temperature of the fluid before it is heated to produce a first temperature detected signal and a downstream thermopile 9 detects the temperature of the fluid before it is heated to produce a second temperature detected signal. The flow rate is computed based on the difference signal between both detected signals. A right thermopile 11 and a left thermopile 13, which are arranged in a direction orthogonal to the flow direction of the fluid, detect the temperature of the fluid to produce a right temperature detected signal and a left temperature detected signal. The property of the fluid is computed on these right and left temperature detected signals. The flow rate is corrected on the basis of the property thus computed. The flow rate of an object fluid for measurement can be accurately measured by a flow sensor whose output characteristic varies when the kind or composition of the fluid changes.

Abstract: A sensing device that comprises a micromachined tube on a substrate for resonant sensing of mass flow and density of a fluid flowing through the tube. The sensing device further incorporates on the same substrate at least a second micromachined tube configured for sensing another property of the fluid, such as pressure, viscosity and/or temperature.

Abstract: A pipe line for fluid to be detected is formed so that heat from a flow rate detector in which a thin-film heating element and a thin-film temperature sensing element are laminated on a first surface of a substrate through an insulating layer is transferred to and absorbed by the fluid. In the flow rate detector, the temperature sensing which is affected by the heat absorption of the fluid due to the heating of the thin-film heating element is executed by the thin-film temperature sensing element, and the flow rate of the fluid in the pipe line is detected on the basis of the temperature sensing result. A fin plate extending into the pipe line is joined to a second surface of the substrate of the flow rate detector by a joint member, and the fin plate extends so as to pass through the central portion on the circular section of the pipe line. The dimension of the fin plate in the direction of the pipe line is larger than the dimension L2 of the thickness.

Abstract: A temperature sensing resistance element includes a substrate made of an insulating material, a temperature sensing resistor formed on at least a part of the outer peripheral surface of the substrate to connect both ends of the substrate, a cap-shaped conducting member being electrically connected to the temperature sensing resistor and disposed at each end of the substrate, and a protective film covering at least the temperature sensing resistor. A gap is defined by an inner surface an enlarged portion of the conducting member and a part of the outer surface of the substrate, and the gap is widened gradually toward the end of the opening of the conducting member.

Abstract: A flow-rate detecting device for a heat-sensitive type flow sensor having high reliability. The device includes a planar substrate having first and second through-holes formed therein in juxtaposition with each other, an insulative supporting film formed over one major surface of the substrate so as to cover the through-holes, a fluid temperature measuring resistor formed by a heat-sensitive resistor film deposited at a location of the first through-hole on the supporting film oppositely to the substrate, a heat generating resistor formed of a heat-sensitive resistance film deposited at a location of the second through-hole on the supporting film oppositely to the substrate, an insulative protection film deposited so as to cover the fluid temperature measuring resistor and the heat generating resistor, and a reinforcing film provided for the fluid temperature measuring resistor. The reinforcing film is not provided for the heat generating resistor.

Abstract: A fluid flow rate measuring apparatus for measuring a flow rate of fluid, including a first heating element which is disposed at an upstream side in a direction of flow of the fluid, a first temperature detecting element which is formed in the vicinity of the first heating element, a second heating element which is disposed at a downstream side in the direction of flow of the fluid, a second temperature detecting element which is formed in the vicinity of the second heating element and a power source which is connected to the first and second heating elements and supplies electric power to the first and second heating elements so as to make a temperature of the first temperature detecting element higher by a predetermined value than that of the second temperature detecting element at all times such that the flow rate of the fluid is measured from a ratio of a quantity of the electric power supplied to the first heating element to that supplied to the second heating element.

Abstract: A flow sensor for determining the velocity and direction of a fluid flow including a substrate, a heat source located on the substrate, and a first and a second heat sensor located on the substrate to detect at least a portion of heat generated by the heat source. The first and second heat sensors and the heat source are arranged in a non-linear orientation.

Abstract: A flowmeter includes a heating resistor and a resistive element for detecting the temperature of the heating resistor. The heating resistor is controlled so that the temperature detected by the resistive element approaches a reference temperature determined based on the temperature of the fluid flow. As a result, the temperature of the upstream side of the heating resistor becomes lower than the reference temperature, while the temperature of the downstream side of the heating resistor becomes higher than the reference temperature. Another resistive element is arranged on the upstream side or the downstream side of the heating resistor for detecting the rate of the fluid flow, and the rate and the direction of the fluid flow are detected by comparing the temperature of the resistive element with the reference temperature. This flowmeter is immune to variation in the resistance of the heating resistor.

Abstract: A gas flowmeter capable of reducing a secular change comprises a silicon semiconductor substrate formed with a cavity and a heat element formed above the cavity of the semiconductor substrate by way of an insulating film. The heat element is a silicon (Si) semiconductor thin film impurity-doped at high concentration. Stoichiometrically stable silicon nitride (Si3N4) thin films as barrier layers which less permeate and less absorb hydrogen in the heat generating temperature range of the heat element are formed above and below the silicon (Si) semiconductor thin film.

Abstract: A flow sensor, which can detect flow velocity in a wide range including high flow velocity area with simple structure. A flow sensor includes a substrate having a hollow portion; and a thin film structure portion provided above the hollow portion. The thin film structure portion is provided with a heater formed in a center portion, an upper and a lower stream temperature detectors for detecting temperature of the fluid, a fluid thermometer for detecting temperature of the fluid, and thermal couple films provided on the substrate at a portion, where is between the heater and both temperature detectors. According to this structure, the thermal couple films enhance thermal coupling between the heater and the temperature detectors.

Abstract: A flow rate detecting element measuring the flow rates of various fluids, particularly the intake air of an internal combustion engine. The flow rate detecting element has a thin film layer including a support film and a protective film on one surface of a flat substrate, a heating resistance section and a comparative resistance section thermosensitive resistor having patterns and located between the support film and the protective film. The flat substrate has a recess which penetrates the flat substrate in the thickness direction thereof and facing the heating resistance section and the comparative resistance section. A fluid flow passage communicates with the recess which faces the comparative resistance section for fluid flow into the recess. Flow rate or velocity of a fluid can be measured accurately using the heating resistance section according to the fluid temperature reported by the comparative resistance section.

Abstract: In a sensor chip according to the existing art, contaminants in the medium flowing past the sensor chip result in deposits in the sensor region.

Abstract: A sensor includes a first insulating layer, a second insulating layer having an opening, a plurality of metal wirings, and a plurality of electrodes. Each metal wiring has a contacting area. Each metal wiring is located between the first and second insulating layers. Each electrode has a bonding region located separately from the contacting area. The electrodes are in electrical connect with the contacting areas through the openings. A part of each metal wiring is located beneath each bonding region. The electrodes include any of aluminum, two metals of gold and titan, or three metals of gold, nickel, and titan. When the electrodes include aluminum, the electrodes are annealed such that the surface roughness of the electrode is smaller than 100 angstroms. When the electrodes include the two or three metals, the electrodes are annealed in an atmosphere that a partial pressure of oxygen is lower than 10−1 Pa.

Abstract: A flow rate sensor for performing a flow rate detection of fluid with high accuracy without suffering adverse effect of the environmental temperature condition even when the fluid is viscous fluid having relatively high viscosity or the flow rate is relatively small is provided. The flow rate sensor includes a flow rate detector having a heating function and a temperature sensing function, and a pipe line for fluid to be detected which is formed so that heat from the flow rate detector is transferred to and absorbed by the fluid. The temperature sensing which is affected by a heat absorption effect of the fluid due to the heat is executed in the flow rate detector, and the flow rate of the fluid in the pipe line is detected on the basis of the temperature sensing result. Unit retaining portions formed on a casing in which the pipe line is formed, the unit retaining portions being disposed adjacent to the pipe line.

Abstract: To measure the flow in a liquid, the liquid (1) is led in a duct (2) along a flow sensor (3). The flow sensor (3) is integrated together with a processing and control circuit on a semiconductor substrate. It comprises a heating and, symmetrically thereto, two temperature sensors. The flow is determined from the temperature difference between the temperature sensors and/or from the power dissipation of the heating. For calibrating the sensor, a valve (4) is provided by means of which the duct (2) can be interrupted. This arrangement allows a flow measurement of high accuracy.

Abstract: An airflow sensor including a housing, a flexible substrate, and electrical components. The housing defines an internal compartment and a top face opening. The substrate includes circuitry traces, and defines a front and a back. The substrate is disposed within the compartment such that the back is exposed relative to the opening. The electrical components are electrically connected to the circuitry traces, extending from the front of the substrate opposite the opening, and include a heated temperature sensor spaced from a baseline temperature sensor. During use, airflow interfaces with the substrate back to cool the heated temperature sensor. The extent of this cooling as compared to the baseline temperature sensor is indicative of airflow. The system and method include detecting the presence or absence of airflow based upon a temperature differential between the temperature sensors as well as a rate of change in the temperature differential.

Abstract: A heating element type mass flow sensor has a composition such that a heating resistor is located substantially in a straight line in the direction perpendicular to the air flow direction; at least a pair of resistance temperature-sensing elements are separately arranged upstream and downstream of the heating resistor, respectively; the heating resistors and the resistance temperature-sensing elements are symmetrically arranged with respect to the air flow direction (the x direction) and the direction perpendicular to the air flow (the y direction), that is, in the two-rotation symmetric manner; and slits are shaped in the respective regions near the two end sides of the heating resistor.

Abstract: Grooves into which an adhesive agent is poured are formed on the adhesion face of a sensor element, the adhesion face being adhered to a surface of a sensor-supporting member, which in turn can make the depth of a layer of the adhesive agent between the sensor element and the sensor-supporting member zero, and remove the difference in level between both the top surfaces of the sensor element and the sensor-supporting member.

Abstract: A thermistor layer made of platinum is formed on a thin diamond film. An amount of heat carried away from the diamond film by a fluid is detected as a change in the temperature of the thermistor layer. The rear side of the diamond film is kept in contact with the fluid to prevent the material of the thermistor from being corroded by the fluid. In another aspect of the invention, a heating element and a thermistor are formed on one surface of a thin diamond film. The other surface is kept in contact with a fluid. The diamond film is heated by the heating element in a quite short time of about 0.2 second. The resulting response characteristics of the diamond film are detected by the thermistor. The flow rate is calculated from the response characteristics.

Abstract: A mass flow sensor includes a semiconductor substrate 1, an insulating thin film 2, heaters 311 and 312, temperature measurement resistors 321 and 322, and a protective layer 4. The heaters 311 and 312 are formed on the surface of the insulating thin film 2, and are provided adjacently such that the heater 311 is provided upstream the heater 312 and the heater 312 is provided downstream the heater 311. A cavity 5 is formed below the heaters 311 and 312, and the heaters are thermally insulated from the remaining portion of the semiconductor substrate. The temperature measurement resistors 321 and 322 are formed on the top surface of the insulating thin film 2, and are provided at opposite sides of the heaters 311 and 312, such that the resistors are aligned with respect to the flow passage of a fluid. In the mass flow sensor and the mass flowmeter including the sensor, the flow rate and flow direction of a fluid can be detected by means of merely the heaters 311 and 312, which are active elements.

Abstract: A flow velocity detector, wherein an upstream side temperature sensor (3U1) and a downstream side temperature sensor (3D1) are disposed on both sides of a heater (2-1) with the recessed and projected direction of the heater (2-1) in comb tooth-shape positioned approximately in parallel with the flow direction A of a detected fluid, whereby heat from the heater (2-1) first heats the crank-shaped connection parts (J) of the temperature sensors (3U1, 3D1) in comb tooth shape, respectively, and then transfers through straight line parts (S) along the crank-shapes in the direction approximately in parallel with the flow direction of the detected fluid.

Abstract: The invention relates to an electrode arrangement for an electronic component, also acting as a support for sensors. Said electrode arrangement is mounted on a substrate (1) as a suitably dimensioned surface-structure of two electro-conductive electrodes which are not electrically connected to one another. The electrode arrangement reproduces the conductivities and/or the substance of a sensor-active layer on the conductance of a measuring head or a functional element when said conductivities of the electrode arrangement and/or substance of a sensor-active layer are reproduced in a highly flexible manner. Said electrode arrangement can be produced in a simple and cost-effective manner. The invention provides for a plurality of conductive islands (3) which are not linked or not essentially linked to one another and which are mounted on a dielectric substrate (1) between two electrodes (2) in the form of a planar two-dimensional arrangement.

Abstract: A fluid flow measuring method is provided which is high in the sensitivity and the response and wide in the dynamic range. A flow measuring apparatus measures flow of fluid based on a difference in radiation of heat between an upstream side and a downstream side of a heating member provided in the fluid. The apparatus includes an upstream temperature sensor provided on the upstream side of the heating member for measuring first temperature; a downstream temperature sensor provided on the downstream side of the heating member for measuring second temperature; and a circuit for controlling power to the heating member to maintain an average temperature level of the first temperature measured by the upstream temperature sensor and the second temperature measured by the downstream temperature sensor at a predetermined level.

Abstract: A chemical preconcentrator with integral thermal flow sensor can be used to accurately measure fluid flow rate in a microanalytical system. The thermal flow sensor can be operated in either constant temperature or constant power mode and variants thereof. The chemical preconcentrator with integral thermal flow sensor can be fabricated with the same MEMS technology as the rest of the microanlaytical system. Because of its low heat capacity, low-loss, and small size, the chemical preconcentrator with integral thermal flow sensor is fast and efficient enough to be used in battery-powered, portable microanalytical systems.

Abstract: A sensor assembly has a substrate with a microchannel formed therein through which a fluid can flow. At least one sensor is proximate to the microchannel. The temperature of the at least one sensor or fluid may indicate the condition of the fluid, for example, the flow rate and the presence of gas bubbles and particulate substances.

Abstract: A mass flow sensor is described. To improve the membrane stability of the known mass flow sensor and to increase the thermal conductivity of a membrane having a greater mechanical stability, in particular the membrane has at least one dielectric or nonconducting adjustment layer with a thermal conductivity which is greater than that of a silicon oxide layer of the same thickness, the adjustment layer being used to adjust the thermal conductivity of the membrane. One of the preferred adjustment layers is polycrystalline silicon.

Abstract: A system for characterizing a liquid comprises a sensor for providing an electrical output signal depending on a characteristic of the liquid, and a processing unit for processing the output signal of the sensor to obtain characterizing data of the liquid. The sensor is made as a single sensor/actuator device and can be connected in a plurality of manners to the processing unit. In at least some of these connecting manners the processing unit is adapted to actuate the sensor/actuator device and to process the output signal of the sensor/actuator device to obtain different characterizing data of the liquid.

Abstract: In a thermal air flow sensor, an air flow measuring element and an intake air temperature sensing element of an intake air temperature sensor are mounted on a single support member so as to be positioned within an intake passage. The support member is made of a glass-ceramic material for example and is held by a holder secured to the wall of an intake pipe. The support member has a structure whereby both sides of a portion of the support member located on the side away from the intake pipe wall are easy to be taken away their heat by an air flow moving through the intake pipe. The air flow measuring element and the intake air temperature sensing element are disposed on such a heat-removed surface of the support member and are electrically connected respectively to conductors disposed on the support member, with their electric connections being sealed with resin, whereby the intake air temperature sensor and the air flow sensor can be rendered integral with each other.

Abstract: A flow sensor, which includes a diaphragm, is made such that the diaphragm is flat or outwardly deformed to allow fluid flow rate measurements at higher flow rates. The diaphragm is made of an upper set of insulating films, electric devices, and a lower set of insulating films. The component layers of the diaphragm are formed such that the average stress in the upper set of insulating films is more compressive than the average stress in the lower set of insulating films.

Abstract: A thin-film type flow sensor having a thin-film part in which a plurality of patterned resistor films are sandwiched between a pair of insulator films. The resistance ratios among the resistor films are minimized from one sensor to another made from the same wafer. The flow sensor has a lower insulator film, the resistor films, and an upper film laminated in succession on a substrate. The resistor films include a patterned fluid thermometer, a temperature detector, and a heater. The heater has a wiring configuration in which resistor elements are connected in a parallel manner. The wiring widths of the heater and the thermometer can thus be made identical, so that the resistance ratios become invariant over the wafer surface, irrespective of a disparity in etching variations.

Abstract: A sensor includes a first insulating layer, a second insulating layer having an opening, a plurality of metal wirings, and a plurality of electrodes. Each metal wiring has a contacting area. Each metal wiring is located between the first and second insulating layers. Each electrode has a bonding region located separately from the contacting area. The electrodes are in electrical connect with the contacting areas through the openings. A part of each metal wiring is located beneath each bonding region. The electrodes include any of aluminum, two metals of gold and titan, or three metals of gold, nickel, and titan. When the electrodes include aluminum, the electrodes are annealed such that the surface roughness of the electrode is smaller than 100 angstroms. When the electrodes include the two or three metals, the electrodes are annealed in an atmosphere that a partial pressure of oxygen is lower than 10−1 Pa.

Abstract: A bi-directional mass air flow sensing device for measuring air flow, comprising a bridge circuit coupled across a voltage potential, wherein the bridge circuit comprises a first side including first and second temperature dependent sensor resistors connected in series and disposed on a thermally insulative substrate window in line with an air flow and arranged such that relative to a first direction of air flow, the first sensor resistor is upstream of the second sensor resistor, and a second side in parallel with the first side and including third and fourth temperature dependent sensor resistors connected in series and disposed on the thermally insulative substrate in line with the air flow such that relative to the first direction of air flow, the third sensor resistor is upstream of the fourth sensor resistor, and a temperature dependent balance resistor connected between the first and second temperature dependent sensor resistors on the first side of the bridge circuit.

Abstract: A bi-directional mass air flow sensing device for measuring air flow, comprising a bridge circuit coupled across a voltage potential, wherein the bridge circuit comprises a first side including first and second temperature dependent sensor resistors connected in series and disposed on a thermally insulative substrate window in line with an air flow and arranged such that relative to a first direction of air flow, the first sensor resistor is upstream of the second sensor resistor, and a second side in parallel with the first side and including third and fourth temperature dependent sensor resistors connected in series and disposed on the thermally insulative substrate in line with the air flow such that relative to the first direction of air flow, the third sensor resistor is upstream of the fourth sensor resistor, and a temperature dependent balance resistor connected between the first and second temperature dependent sensor resistors on the first side of the bridge circuit.

Abstract: A flow sensor includes a substrate in which a cavity is formed. A thin film structure is located above the cavity. The thin film structure includes a patterned multilayer film. A dummy film layer is formed or a number of dummy film layers are formed in close proximity to the patterned multilayer film to protect the multilayer film from the effect of reduction gas.

Abstract: A sensing device that comprises a micromachined tube on a substrate for resonant sensing of mass flow and density of a fluid flowing through the tube. The sensing device further incorporates on the same substrate at least a second micromachined tube configured for sensing another property of the fluid, such as pressure, viscosity and/or temperature.

Abstract: The temperature sensing resistance element comprises a substrate made of an insulating material, a temperature sensing resistor formed on at least a part of the outer peripheral surface of the substrate so as to connect both ends of the substrate, a cap-shaped conducting member being electrically connected to the temperature sensing resistor and disposed at each end of the substrate, and a protective film covering at least the temperature sensing resistor. There is provided with a gap which is defined by an inner surface of the enlarged portion and a part of the outer surface of the substrate, and is widened gradually toward the end of the opening of the conducting member.

Abstract: An air-mass sensor having an air mass sensor module provided with two temperature sensors (6, 7) and two heat sensors (4, 5) which are incorporated into two separately acting bridges (I, II) whose bridge output signals (Umv, Umh, Umq) are supplied to a microprocessor (16) incorporated on a common support with the air-mass sensor module. The microprocessor (16) is calibrated such that crude bridge signals (Usv, Ush, Usq) measured in a base mode are inscribed in support places (x1, x2, x3) of support place tables (St2, St3). A customer characteristic curve is filed in the form of measurement points (m1, m2, m3) in the support place tables (St2, St3) and are utilized to adjust the crude bridge signals.

Abstract: To provide a thermosensitive flow rate detecting in which no response lag occurs even if the flow rate change frequency is high, and no error in detection flow rate is produced even if the power source change would occur, a thermosensitive flow rate detecting device is provided which includes: a heat generating resistor provided in fluid to be measured for generating heat by electric power consumed in accordance with a flow rate of the fluid to be measured; a first temperature detecting resistor for detecting a temperature of the fluid to be measured which changes according to the flow rate; and a second temperature detecting resistor for detecting the temperature of said heat generating resistor, further including a bridge circuit provided with the first temperature detecting resistor and the second temperature detecting resistor, the heating current of the heat generating resistor being controlled such that a temperature difference between the first temperature detecting resistor and the second temperature

Abstract: A thermosensitive flow rate sensor includes a detecting element, in which a heating element and a fluid temperature detector are formed so as to be separated from each other on a surface of a flat substrate and a flow rate detection diaphragm is formed under a region where the heating element is formed, and a support having a recess portion, the detecting element being housed inside the recess portion such that a surface of the detecting element is positioned generally in a common plane with a surface of the support and such that a direction of alignment of the heating element and the fluid temperature detector is perpendicular to a direction of flow of a fluid being measured, and a groove being formed in the support so as to pass under a region where the fluid temperature detector is formed in the direction of flow of the fluid being measured.