A thermally responsive flow meter may comprise a coil and a plate coupled to the coil. The plate may define a first airflow aperture. The plate may translate in a circumferential direction in response to a thermal expansion of the coil. The thermally responsive flow meter may regulate the flow of air through a second airflow aperture.

A flow measurement device includes a flow rate measurement unit, an arithmetic unit that calculates a difference value between a the first flow rate value and a second flow rate value, and a difference value conversion unit that calculates a flow rate ratio, based on the difference value. An appliance characteristic extraction unit extracts at least one appliance characteristic quantity indicating a characteristic of a flow rate change and a value calculated from a first flow rate value and a second flow rate value, as an appliance characteristic quantity. Furthermore, an appliance inherent characteristic information holding unit holds appliance inherent characteristic quantities indicating a characteristic flow rate state of a specific gas appliance, and an appliance discrimination unit discriminates a gas appliance, based on a comparison between the appliance characteristic quantity and the appliance inherent characteristic quantity.

To obtain a chip package positioning structure capable of adjusting a tilt and a position of a chip package with respect to the circuit board and reducing mounting variations. The chip package positioning and fixing structure that positions and fixes, to a circuit board 4, a chip package 5 in which a flow rate detection element 53 is sealed with a resin so that a detection portion is at least exposed, in which the chip package includes a solder fixation portion 52 that fixes the chip package to the circuit board by soldering, and a positioning portion 514 that performs positioning to the circuit board, and the positioning portion is provided closer to the flow rate detection element from the solder fixation portion.

A system for measuring gas flow generally including a passive acoustic wave generator disposed in a gas flow stream to passively generate an audio signal through vortex shedding, a sound capturing instrument disposed outside the gas stream to produce an electrical signal representative of the acoustic signal, a temperature sensor to obtain temperature measurements indicative of the temperature of the gas flow stream and a control system for determining the gas flow, such as velocity or flow rate, as a function of the acquired acoustic and temperature measurements. The acoustic wave generator includes a corrugated flow channel whose geometric design is so tuned to generate an acoustic emission whose frequency signature varies as a function of the gas flow velocity. The control system may acquires time-domain acoustic data, and process that data to obtain a frequency-domain representation from which gas velocity or gas flow rate can be determined.

Techniques detect a low gas-pressure condition within a region without the use of pressure sensors. In an example, gas usage at a service site is disaggregated to show use by individual appliances. A flowrate of gas at an appliance (e.g., a gas hot water tank) having a generally fixed-rate of gas-consumption is determined. Based at least in part on the flowrate of gas at the appliance, and an historical gas flowrate at that appliance, it is determined if gas pressure at the service site is lower than expected. In an example, failure of the appliance to use its typical fixed-flowrate may indicate low gas pressure at the service site. Information is obtained from a second gas meter at a second service site. Based on the gas pressure at the first and second service sites being lower than expected, a low gas pressure situation may exist in a regional area.

Provided is an internal combustion engine control device capable of more appropriately correcting an output value of a flow rate sensor that measures a flow rate of air flowing through an intake flow path of an internal combustion engine, and further reducing an error between a corrected air flow rate and an actual air flow rate as compared to a conventional device. For this purpose, the internal combustion engine control device of the present invention includes an arithmetic device 100 including a fundamental frequency derivation unit 104 that derives a fundamental frequency, a flow rate amplitude calculation unit 107 that extracts a radio frequency of a plurality of frequencies equal to or higher than the fundamental frequency from a pulsation waveform based on the output value of the flow rate sensor as a flow rate radio frequency and calculates an amplitude of the flow rate radio frequency for each frequency, a correction amount derivation unit 108 that derives a correction amount based on the amplitude of the flow rate radio frequency for each frequency, and a flow rate calculation unit 109 that calculates a flow rate of air by using the output value of the flow rate sensor and the correction amount.

To obtain a low-pressure-loss physical quantity detection device that can detect a plurality of physical quantities of intake air. A physical quantity detection device of the present invention that detects a plurality of physical quantities of a measured gas flowing in a main passage, the physical quantity detection device includes: a circuit board on which a sensor that detects the plurality of physical quantities and an electronic component that controls the physical quantities are mountable; a circuit board accommodating unit that accommodates the circuit board; and a sub-passage in which a flow sensor is disposed. The circuit board is accommodated in the circuit board accommodating unit on an upstream side of the sub-passage, and disposed in parallel with the measured gas flowing through the main passage.

Devices, methods, and systems for operating gas meters are described herein. The systems may include a gas measuring system connectable to a gas line, where the gas measuring system may include a flow rate sensor, a pressure sensor, and a controller in communication with the flow rate sensor and the pressure sensor. The flow rate sensor and the pressure sensor may be configured to sense measures of a gas passing through the gas line. The controller may repeatedly obtain pressure measurements at set pressure measurement times. Measures from the flow sensor may be monitored and when a measure from the flow sensor measure meets a flow rate criteria, the controller may trigger an extra pressure measurement without waiting for a next pressure measurement time. The controller may initiate closing of a gas valve when a measure from the pressure sensor exceeds a threshold value.

Provided is a physical quantity detection device capable of achieving both rigidity improvement and sealability improvement. A physical quantity detection device (20) of the invention includes a housing (100), a cover (200), a chip package (310), and a flow rate sensor (311) supported by the chip package and arranged in a sub-passage. The housing includes: a first adhesive groove 160A which is an adhesive groove to which an adhesive for bonding the cover is applied, extends along a proximal end of the housing, extends in the protruding direction of the housing from the proximal end of the housing to a position on a more distal end side of the housing than the chip package, and is applied with the first adhesive 401; and a second adhesive groove 160B which extends along the sub-passage 134 and is applied with the second adhesive 402. The first adhesive has a higher Young's modulus, and the second adhesive has a higher thixotropy.

Provided is a physical quantity detection device capable of achieving both rigidity improvement and sealability improvement. A physical quantity detection device (20) of the invention includes a housing (100), a cover (200), a chip package (310), and a flow rate sensor (311) supported by the chip package and arranged in a sub-passage. The housing includes: a first adhesive groove 160A which is an adhesive groove to which an adhesive for bonding the cover is applied, extends along a proximal end of the housing, extends in the protruding direction of the housing from the proximal end of the housing to a position on a more distal end side of the housing than the chip package, and is applied with the first adhesive 401; and a second adhesive groove 160B which extends along the sub-passage 134 and is applied with the second adhesive 402. The first adhesive has a higher Young's modulus, and the second adhesive has a higher thixotropy.