US 11,703,470 B2
Sensor device for determining heat transfer parameters of a fluid
Mark Hornung, Stäfa (CH); and Eric Monnin, Stäfa (CH)
Assigned to Sensirion AG, Stäfa (CH)
Filed by Sensirion AG, Stäfa (CH)
Filed on Jun. 21, 2021, as Appl. No. 17/353,076.
Claims priority of application No. 20181410 (EP), filed on Jun. 22, 2020.
Prior Publication US 2021/0396696 A1, Dec. 23, 2021
Int. Cl. G01N 25/18 (2006.01); G01N 25/48 (2006.01)
CPC G01N 25/18 (2013.01) [G01N 25/482 (2013.01); G01N 25/4826 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A sensor device for determining at least one heat transfer parameter of a fluid of interest, the fluid of interest being a gas, the sensor device comprising:
a support plate having a mounting surface;
a sensor unit comprising at least one heater element and at least one temperature sensor;
a first housing defining an interior and an exterior, the first housing being mounted on the mounting surface of the support plate, the sensor unit being received in the first housing, the first housing comprising a first membrane, the first membrane allowing diffusive gas exchange of the fluid of interest between the exterior and the interior of the first housing; and
a second housing defining an interior and an exterior, the second housing being mounted on the mounting surface of the support plate, the second housing having the form of a cap that is open towards the support plate, the cap defining a circumferential rim that is connected to the support plate, the first housing being received in the interior of the second housing, the second housing comprising a second membrane, the second membrane allowing diffusive gas exchange of the fluid of interest between the exterior of the second housing and the exterior of the first housing,
wherein the second housing comprises a base body, the second membrane being disposed in or on one or more openings of the base body, and
wherein the base body of the second housing comprises or essentially consists of a thermally conductive material having a thermal conductivity of at least 10 W/mK at 20° C.,
wherein the support plate comprises a thermally conductive layer made of a thermally conductive material having a thermal conductivity of at least 10 W/mK at 20° C., at least part of the thermally conductive layer overlapping with a portion of the mounting surface that faces the interior of the second housing, and
wherein the second housing is connected to the thermally conductive layer of the support plate in a thermally conductive manner.