Abstract:
Thermisches Durchflussmessgerät (1), insbesondere zur Bestimmung und/oder Überwachung des Massedurchflusses (Φ Μ ) und/oder der Durchflussgeschwindigkeit (v D ) eines strömungsfähigen Mediums (3) durch eine Rohrleitung (2) mit zumindest drei Sensorelementen (4a, 4b, 4c) und einer Elektronikeinheit (9), sowie ein Verfahren zum Betreiben eines thermischen Durchflussmessgeräts (1), wobei jedes der zumindest drei Sensorelemente (4a, 4b, 4c) zumindest teilweise und/oder zeitweise mit dem Medium (3) in thermischem Kontakt steht, und einen beheizbaren Temperatursensor (5a, 5b, 5c) umfasst, wobei die Elektronikeinheit (9) dazu ausgestaltet ist, jedes der drei Sensorelemente (4a, 4b, 4c) mit einer Heizleistung (P1,P2,P3) zu heizen, dessen Temperatur (T1,T2,T3) zu erfassen, und zumindest zwei der zumindest drei Sensorelemente (4a, 4b, 4c) gleichzeitig zu heizen, kontinuierlich den Massed urchfluss (Φ Μ ) und/oder die Durchflussgeschwindigkeit (v D ) des Mediums (3) zu ermitteln, und gleichzeitig aus einem paarweisen Vergleich der Temperaturen (T11,T12,...) und/oder Heizleistungen (P11, P12,...) eine Aussage über den Zustand (D 1 ,D 2 ,D 3 ) von zumindest einem der zumindest drei Sensorelemente (4a, 4b, 4c) zu treffen, und im Falle dass eine Fehlfunktion und/oder eine Belagsbildung an zumindest einem der zumindest drei Sensorelemente (4a, 4b, 4c) auftritt, eine Korrektur des Messwerts für den Massed urchfluss (Φ Μ ) und/oder die Durchflussgeschwindigkeit (v D ) durchzuführen und/oder eine Meldung über den Zustand des zumindest einen Sensorelements (4a,4b,4c) zu generieren und auszugeben.
Abstract:
A nebulizer (10) comprises a head detachably coupled to a body. The head comprises nebulizing means (42, 40, 44), an air channel (50) and a flow sensor (52). A nebulized liquid is released in an air channel (50) that ends in a mouth piece 70 through which a user inhales (5) and exhales (7). The inhaling and exhaling causes a flow in the air channel which is detected with the flow sensor (52). The nebulizing means are controlled by control means (60, 62) included in the body.
Abstract:
A thermal flow sensor integrated circuit for sensing flow in a channel based on temperature measurements, the integrated circuit having a temperature sensing element (30) on a front side of the integrated circuit arranged to face the channel, and a bond pad (60, 200) coupled electrically to the temperature sensing element, for making electrical contact off the integrated circuit, the bond pad being arranged to face away from the channel. By having the bond pad facing away from the channel, the space needed for the bond pad and any connections to it need not extend beyond the temperature sensing element and get in the way of the channel. Hence the temperature sensing element can be located closer to the channel or in the channel to enable measurements with better response time and sensitivity.
Abstract:
The invention relates to a device for measuring the flow speed of a fluid as well as its direction and its orientation, based on a thermal-sensor measurement principle, that comprises at least three flow measurement probes (1, 1a,..., 1f) each having a sensitive member (2) and an obstacle (3) masking a predetermined measurement area of the sensor, characterised in that the flow measurement probes are attached on carrier posts (7), said carrier posts (7) defining said obstacles (2) that form masking members (4) for an angular sector of the flow measurement probes facing the sensitive member of said probes.
Abstract:
A flow velocity sensor, comprising a base stand having a space part, a thin-film layer formed on the surface of the base stand where the space part is formed, a first temperature measuring resistance element and a second temperature measuring resistance element formed on the thin-film layer and connected in series to each other, a flow velocity calculation means for calculating the flow velocity of fluid based on a temperature difference between the first and second temperature measuring resistance elements, and a control means for controlling the first and second temperature measuring resistance elements so that the averaged temperature of the first and second temperature measuring resistance elements is always higher by a specified temperature than the ambient temperature.
Abstract:
A microscale out-of-plane thermal sensor (10, 100). A resistive heater (12) is suspended over a substrate (14) by supports (16) raised with respect to the substrate to provide a clearance (20) underneath the resistive heater for fluid (22) flow. A preferred fabrication process for the thermal sensor uses surface micromachining and a three-dimensional assembly to raise the supports and lift the resistive heater over the substrate.
Abstract:
This invention is a flow measurement device that has high spatial (less than 1.0 x 1.0 mm 2 ) and temporal resolution (greater than 10s to 100s kHz) to measure flow properties in unsteady and direction-reversing conditions. The present invention can have an oscillating substrate, hot wire prongs, a hot wire attached to the hot wire prong, sensor leads from the prongs to a constant temperature anemometry circuit (CTA), means for the oscillating substrate to oscillate the substrate at a frequency greater than a characteristic cycle frequency of the flow to be measured, at a frequency less than a CTA bandwidth frequency, and such that a frequency and amplitude (A w ) of oscillation are sufficiently large to be detected, and means to obtain two measurements during an oscillation cycle when the hot wire is at its maximum oscillation velocity. Alternatively, the prongs can be eliminated and a hot wire or hot film can be directly applied to the oscillating substrate.