Thermal mass flow meter

About: Thermal mass flow meter is a research topic. Over the lifetime, 1759 publications have been published within this topic receiving 21878 citations.

Means for determining flow rate and volume of a flowing fluid mass

Abstract: A system which includes a flow meter producing voltage pulses of a frequency proportional to the flow rate of a flowing mass, and a sensing element responsive to a physical condition of the flowing mass with a circuit which produces a DC voltage signal analogous to that condition. A generator provides linear sawtooth voltage pulses against which a comparator circuit compares the analog voltage from the sensing element and circuit. The voltage resultant of the comparison switches a portion of the voltage pulses from the flow meter to a divider circuit element and a subtractor circuit element of the system for conversion of relatively low order changes in the physical condition to their full range equivalents, and for correction of the flow rate or volume as a function of such changes. The flow rate or volume as thus corrected is registered on a suitable flow rate indicator or volume counter.

Pressure type flow control system with flow monitoring, and method for detecting anomaly in fluid supply system and handling method at abnormal monitoring flow rate using the same

Abstract: A pressure type flow control system with flow monitoring includes an inlet, a control valve including a pressure flow control unit connected downstream of the inlet, a thermal flow sensor connected downstream of the control valve, an orifice installed on a fluid passage communicatively connected downstream of the thermal flow sensor, a temperature sensor provided near the fluid passage between the control valve and orifice, a pressure sensor provided for the fluid passage between the control valve and orifice, an outlet communicatively connected to the orifice, and a control unit including a pressure type flow rate arithmetic and control unit receiving a pressure signal from the pressure sensor and a temperature signal from the temperature sensor, and a flow sensor control unit to which a flow rate signal from the thermal flow sensor is input.

Mass-flow sensor with a molded flow restrictor

Abstract: A high mass-flow sensing apparatus and method of forming the same, comprising a flow tube bypassed in a flow path defined by a flow channel, through which a fluid flows. A flow sensor can be disposed in the flow tube for measuring a flow rate of the fluid in the flow channel. A set of narrow rectangular flow restrictors can be molded into the flow tube and adjacent to the flow sensor. Each flow restrictor can include several rectangular cutouts that are molded into upstream and/or downstream portions of the flow tube in order to limit the flow rate of the fluid across the flow sensor. The flow restrictors can laminarize the flow rate of the fluid in the flow tube and thereby reduce flow turbulence and lead to optimal sensing performance of the flow sensor.

Method of flow measurement and flow meter

Abstract: A method of urine flow measurement where liquid in the form of a free-fall jet is collected in a collecting vessel and the vertical force produced by the collecting vessel on a measuring device, for example a scale or the like, is sensed, and the change in time of said force is utilized for obtaining a measure of the flow corresponding to the jet. The method is especially characterized in that the effect of the impulse of the jet on the sensed force is eliminated by deflecting the vertical flow constituted by the jet to a substantially horizontal flow by a rotating device before the liquid is caused to contact the vessel. The invention also relates to a flow meter.