Abstract: A thermal type flowmeter includes a sensor, a correcting unit, and a flow-rate calculating unit. The sensor outputs a sensor value (first value) corresponding to the state of thermal if fusion in a fluid heated by a heater which is being driven in such a manner that the difference between the temperature of the heater and the temperature of the fluid at a location free from thermal influence of the heater is equal to a predetermined temperature difference. The correcting unit calculates a corrected sensor value (second value) by correcting the sensor value output by the sensor, in accordance with the temperature of the fluid, and outputs the corrected sensor value. The flow-rate calculating unit calculates the flow rate of the fluid from the corrected sensor value calculated by the correcting unit.

Abstract: A thermal flowmeter includes a first thermal resistance element that detects a first temperature of a fluid, a second thermal resistance element disposed downstream to detect a second temperature of the fluid, a control unit that causes the second thermal resistance element to heat to make the second temperature higher than the first temperature by a fixed value, a power measurement unit that measures a power applied to the second thermal resistance element, a power conversion unit that multiplies the power measured by the power measurement unit, by a constant uniquely determined depending on the fluid, thereby converting the power to a power required when the fluid is water, and a flow rate calculation unit that calculates a flow rate of the fluid, by converting the power converted by the power conversion unit to a value of the flow rate, using a flow rate conversion characteristic formula applicable to water.

Abstract: A calorific value calculation formula generating system is equipped with a measuring mechanism for measuring heat dissipation constant values or thermal conductivity values of each of plural mixed gases each containing plural kinds of gas components at plural temperatures; and a formula generation module for generating a calorific value calculation formula having heat dissipation constant or thermal conductivities at the plural temperatures as independent variables and a calorific value as a dependent variable on the basis of calorific value values of the plural mixed gases and the heat dissipation constant values or the thermal conductivity values measured at the plural temperatures.

Abstract: A heat radiation coefficient C [=Ph/(Th?To)] from a microheater is calculated in accordance with a power Ph applied to the microheater which is supported in air and provided in an ambient gas, a heater temperature Th, and an ambient temperature To at this moment. Further, a thermal conductivity ?(T) of the ambient gas is obtained from the calculated heat radiation coefficient C based on a proportional relation [C=K·?(T)] between a thermal conductivity ?(T) of the ambient gas and the heat radiation coefficient C at a measurement temperature T [=(Th?To)/2].

Abstract: To provide a flow meter, and a flow volume controlling device equipped therewith, capable of reducing pressure loss while obtaining a flow rectifying effect in a measurement fluid. A flow meter for measuring the flow volume of a measurement fluid, equipped with a flow path wherein the measuring fluid flows, and a flow rectifier that is disposed within the flow path, where the flow rectifier has holes for rectifying the flow of a measurement fluid, and has an area that is wider than the flow path cross-sectional area in a direction that is perpendicular to the direction in which the flow path extends. The flow volume controlling device is provided with the flow meter, a controlling valve, and controlling means for adjusting the flow volume of a fluid that flows through the flow path of the flow meter through controlling the controlling valves based on information regarding the flow volume detected by the flow meter.

Abstract: To provide a highly accurate flow meter. A Flow meter comprising an inflow opening into which a measurement fluid flows, an outflow opening from which a measurement fluid flows, and a flow path connecting the inflow opening and the outflow opening, wherein the flow path is bent at a first bend portion, wherein: a first porous plate is disposed in the first bend portion of the flow path at an angle relative to the direction in which the flow path extends before and after the first bend portion, and a flow sensor for detecting the flow speed or flow volume of a measurement fluid that flows in the flow path, disposed on the inner wall of the flow path on the outflow opening side of the first bend portion.

Abstract: A heater pattern is arranged on at least one substrate among substrates configuring a package, and a temperature in the package is controlled by controlling a quantity of electricity carried to the heater pattern corresponding to the ambient temperature of a sensor chip in the package.

Abstract: A package is configured by stacking a flat board whereupon a rectangular hole for storing a sensor chip is formed, a flat board whereupon a hole section to be a package inner channel for introducing a measurement target gas into the sensor chip is formed, and a flat board whereupon hole sections which communicate with the package inner channel as an inlet and an outlet of the measurement target gas on the same end surface of the package are formed.

Abstract: To provide a flow meter, and a flow volume controlling device equipped therewith, capable of reducing pressure loss while obtaining a flow rectifying effect in a measurement fluid. A flow meter for measuring the flow volume of a measurement fluid, equipped with a flow path wherein the measuring fluid flows, and a flow rectifier that is disposed within the flow path, where the flow rectifier has holes for rectifying the flow of a measurement fluid, and has an area that is wider than the flow path cross-sectional area in a direction that is perpendicular to the direction in which the flow path extends. The flow volume controlling device is provided with the flow meter, a controlling valve, and controlling means for adjusting the flow volume of a fluid that flows through the flow path of the flow meter through controlling the controlling valves based on information regarding the flow volume detected by the flow meter.

Abstract: To provide a highly accurate flow meter. A Flow meter comprising an inflow opening into which a measurement fluid flows, an outflow opening from which a measurement fluid flows, and a flow path connecting the inflow opening and the outflow opening, wherein the flow path is bent at a first bend portion, wherein: a first porous plate is disposed in the first bend portion of the flow path at an angle relative to the direction in which the flow path extends before and after the first bend portion, and a flow sensor for detecting the flow speed or flow volume of a measurement fluid that flows in the flow path, disposed on the inner wall of the flow path on the outflow opening side of the first bend portion.

Abstract: A heat radiation coefficient C [=Ph/(Th?To)] from a microheater is calculated in accordance with a power Ph applied to the microheater which is supported in air and provided in an ambient gas, a heater temperature Th, and an ambient temperature To at this moment. Further, a thermal conductivity ?(T) of the ambient gas is obtained from the calculated heat radiation coefficient C based on a proportional relation [C=K·?(T)] between a thermal conductivity ?(T) of the ambient gas and the heat radiation coefficient C at a measurement temperature T [=(Th?To)/2].

Abstract: An air suction passage (4A, 4B) is provided with a pick and place confirming sensor (1) comprising a gas flow sensor. The pick and place confirming sensor (1) measures the flow rate of air sucked in from an air suction port (33) of a pick and place nozzle (2). The presence or absence of a part lifted to the pick and place nozzle (2) is detected on the basis of the measurement result.

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: An air suction passage (4A, 4B) is provided with a pick and place confirming sensor (1) comprising a gas flow sensor. The pick and place confirming sensor (1) measures the flow rate of air sucked in from an air suction port (33) of a pick and place nozzle (2). The presence or absence of a part lifted to the pick and place nozzle (2) is detected on the basis of the measurement result.

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: A flow meter is provided which employs a thermal flow sensor and a correcting flow meter, for example, a Karman vortex flow meter such that the output from the thermal flow sensor is corrected by the Karman vortex flow meter, thereby making it possible to accurately and stably measure the flow rate of fluids in a wide range even if the composition of fluids changes.

Abstract: A respiratory air flowmeter includes a flow path forming member, a restricting portion, rectifying lattices, and a sensor. The flow path forming member forms a flow path in which respiratory air flows. The restricting portion and the rectifying lattices are arranged in the flow path in order to stabilize a respiratory air flow. The sensor is mounted in a sensor mounting portion of the flow path forming member, and detects a flow rate of respiratory air flowing in the flow path.

Abstract: A zero point compensating circuit for a microbridge flow meter including an upstream thermal sensor means, a downstream thermal sensor means and a heater means located between said upstream and downstream thermal sensor is provided which comprises a first switch coupled to said heater for turning on and off the same and a current supply circuit coupled to said upstream and downstream thermal sensors for selectively supplying the same with a first current when said first switch is closed and a second current larger than said first current when said first switch is opened such that said upstream and downstream thermal sensors reach a temperature to which they are heated when said heater is on in no flow condition. Thus, an offset caused by discrepancy in the resistance value and thermal coefficients of resistance (TCR) of the upstream and downstream temperature sensors can be removed by the above circuit, thereby making it possible to achieve a precise measurement of small flow rates of a fluid of interest.

Abstract: A flow sensor comprising a flow passage, a rectifying element such as a plurality of screens or a honeycomb structure or both, arranged in the flow passage, a flow passage reducer for reducing the flow passage behind the rectifying element, and a thermal flow sensor, such as for example a micro bridge sensor, mounted at a location immediately behind the reducer. The above structure can largely reduce disturbance in flow to thereby enable highly accurate measurements of a wide range of flow without a low pass filter.

Abstract: A fluid flow speed measuring apparatus comprising a first pipe having an opening exposed into a fluid to be measured, a direction of the opening having an angle larger than a critical negative pressure angle, a second pipe having an opening exposed into the fluid to be measured, a direction of the opening of the second pipe having an angle larger than the critical negative pressure angle and at least one of conditions such as a diameter, a direction, and the number of the openings for determining a magnitude of the negative pressure being different from that of the opening of the first pipe, negative pressure difference detector for detecting a difference between negative pressures acting on the openings of the first and second pipes, and device for calculating a flow speed of the fluid to be measured on the basis of an output from the negative pressure difference detector.