A flowmeter is configured to measure a flow rate of a gas flowing through a main passage. The flowmeter includes a housing and a flow rate detector. The housing is made of a resin and includes a bypass passage branched off from the main passage. The flow rate detector is disposed in the bypass passage and transmits detection signals in accordance with the flow rate of the gas flowing through the main passage. The housing includes a non-insulation portion including graphite.

Devices and methods are described herein for directly and accurately measuring sweat flow rates using miniaturized thermal flow rate sensors. The devices (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500) include the flow rate sensors (220, 320, 420, 520, 620, 720, 820, 920, 1020, 1120, 1220, 1320, 1420) in or adjacent to a microfluidic component (230, 330, 430, 530, 630, 730, 830, 930, 1030, 1130, 1230, 1330, 1430, 1530) of a wearable sweat sensing device. The devices and methods optimize the sensitivity of the flow rate sensors, while minimizing the presence of noise, in order to accurately and directly measure sweat flow rates.

A gas flow control system for delivering a plurality of gas flows. The gas flow control system has a gas flow path extending from a gas inlet to first and second gas outlets. First and second flow restrictors are operably coupled to the gas flow path. First and second valves are operably coupled to the gas flow path such that when both first and second valves are in a fully open state, flows of gas from the first and second gas outlets are split according to the impedances of the first and second flow restrictors.

The packaged flow sensor is a packaged flow sensor for use by being fixed to an external substrate and includes a flow sensor chip including a sensor unit configured to detect a flow rate of a fluid, a case member including an opening toward the external substrate and configured to house the sensor unit in a state in which the sensor unit faces the opening, and a fixing member protruding from the case member toward the external substrate and configured to fix the packaged flow sensor to the external substrate.

An object is to improve measurement accuracy of a flow rate measurement device. A flow rate measurement device including: a first void which is formed of one surface of the support body and one surface of the circuit board; a second void which is formed of a surface opposite to the one surface of the circuit board and the housing; and a third void which is formed of a surface opposite to the one surface of the support body and a cover.

A flow sensor including a fluid flow path, a first sensor configured to determine a first measurement of a thermal diffusivity and/or a viscosity of a fluid in the fluid flow path, a second sensor configured to determine a second measurement of a fluid flow velocity and/or a volumetric flow rate of the fluid in the fluid flow path, and at least one processor configured to adjust the second measurement based on the first measurement. A method including receiving fluid in a fluid flow path of a flow sensor, determining a first measurement of a thermal diffusivity and/or a viscosity of the fluid in the fluid flow path, determining a second measurement of a fluid flow velocity and/or a volumetric flow rate of the fluid in the fluid flow path, and adjusting the second measurement based on the first measurement.

A flow sensor including a fluid flow path, a first sensor configured to determine a first measurement of a thermal diffusivity and/or a viscosity of a fluid in the fluid flow path, a second sensor configured to determine a second measurement of a fluid flow velocity and/or a volumetric flow rate of the fluid in the fluid flow path, and at least one processor configured to adjust the second measurement based on the first measurement. A method including receiving fluid in a fluid flow path of a flow sensor, determining a first measurement of a thermal diffusivity and/or a viscosity of the fluid in the fluid flow path, determining a second measurement of a fluid flow velocity and/or a volumetric flow rate of the fluid in the fluid flow path, and adjusting the second measurement based on the first measurement.

A mass flow control apparatus is capable of controlling a flow rate of a fluid to a tool. Pressure of the fluid is regulated by a solenoid valve, which receives signals from a control module. Various set points may be inputted to the control module, whereby control module receives pressure sensor signals from across a flow restrictor and adjusts the solenoid valve to control the fluid flow rate to equal a set point.

A physical quantity measurement device includes a housing forming a measurement flow path through which the fluid flows and a container space that houses a part of a detection unit. An inner surface of the housing includes a housing intersecting surface that intersects an arrangement direction in which the measurement flow path and the container space are arranged, a housing flow path surface extending from the housing intersecting surface toward the measurement flow path, and a housing container surface extending from the housing intersecting surface toward the container space. The housing includes a housing partition that protrudes from the inner surface toward the detection unit and contacts the detection unit between the housing and the detection unit such that the housing partition separates the measurement flow path and the container space from each other.

Devices and methods are described herein for directly and accurately measuring sweat flow rates using miniaturized thermal flow rate sensors. The devices (100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500) include the flow rate sensors (220, 320, 420, 520, 620, 720, 820, 920, 1020, 1120, 1220, 1320, 1420) in or adjacent to a microfluidic component (230, 330, 430, 530, 630, 730, 830, 930, 1030, 1130, 1230, 1330, 1430, 1530) of a wearable sweat sensing device. The devices and methods optimize the sensitivity of the flow rate sensors, while minimizing the presence of noise, in order to accurately and directly measure sweat flow rates.