Patent ID: 7780348

Claim:
Temperature sensor for a resistance thermometer comprising an electric measuring resistor the resistance material of which consists either of a ceramic material or of a metallic resistance material in combination with a ceramic or a mineral carrier, a protective tube comprising a closed tip and a rear end that provides an access to the inner space of the protective tube and that contains the measuring resistor closely adjacent the closed tip of the protective tube, said protective tube having a restriction at the location of a maximum of packing density of a filler, the restriction being a reduced portion of the protective tube, the protective tube having a wider portion on each side of the reduced portion, the packing density being a maximum at the reduced portion and being less than a maximum on each side of the reduced portion, at least one supply line that is brought out through the rear end of the protective tube, and an electrically insulating filler based on a ceramic or a mineral material that fills the space between the protective tube on the one side and the measuring resistor and its at least one supply line on the other side, wherein the packing density of the filler has a gradient in lengthwise direction of the protective tube.