Back to results
US 4,305,112 AGranted
Capacitance humidity sensing element
AssigneeSiemens Aktiengesellschaft
InventorsHermann Heywang, Johann Kammermaier, Joachim Rauhut
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeSiemens Aktiengesellschaft
InventorsHermann Heywang, Johann Kammermaier, Joachim Rauhut
Estimating the term…
A multi-layered capacitive humidity sensing element having a carrier material separated from a water vapor permeable, electrically conductive coating by an insulating layer which is humidity sensitive, and a method for its manufacture is provided. A metal foil is utilized as the carrier material serving both as a support frame and as an electrically conductive layer. A thin gold layer is applied to the insulating layer, which is formed out of a synthetic material. The gold layer is sufficiently permeable to allow water vapor to freely diffuse into the synthetic layer from the surrounding atmosphere, yet remains thick enough to function as an electrically conductive outer layer. The sensing element thus constructed has both a short response time and an improved simplicity of manufacture.
An improved capacitive humidity sensing element of the type in which a carrier consisting of a material which is not humidity sensitive is separated from a water-vapor permeable, electrically conducting coating by a humidity sensitive, insulating layer attached to said carrier wherein the improvement comprises:
An improved capacitive humidity sensing element of the type in which a carrier consisting of a material which is not humidity sensitive is separated from a water-vapor permeable, electrically conducting coating by a humidity sensitive, insulating layer attached to said carrier wherein the improvement comprises:
Dependencies are inferred from the claim text.