Patent ID: 6615658
Filing Date: 2003-09-09
Classification: G01F

Abstract:
A system for detecting the level of a liquid in a vessel, comprising:a detector assembly including a thermally conductive substrate; means for supporting said substrate within the vessel, a heater mounted on said substrate within the vessel such that said heater is thermally coupled to the interior of the vessel, said heater being able to be actuated to add heat to the surface of the substrate thermally coupled to the interior of the vessel, and a sensor mounted on said substrate within the vessel in proximity to said heater, said sensor being thermally coupled to the interior of the vessel to detect the temperature therein in proximity to said sensor, said sensor being able to be actuated to generate an electrical signal defining a temperature signal indicative of said detected temperature; a processor electrically connected to said sensor for receiving said temperature signal after actuation of said heater, said processor being programmed to calculate a temperature index proportional to said temperature signal, said processor being further programmed to compare said temperature index to a reference thereby to generate an electrical signal defining an elevation signal indicative of the elevation of the upper surface of the liquid being either above or below said sensor; an interface electrically connected to said processor for receiving said elevation signal for use as the basis for communicating to the user the relative elevation of the liquid upper surface as either above or below said sensor; a power supply electrically connected to said heater, sensor, processor, and interface; a fixture for supporting said substrate in depending relation relative to the upper inner surface of the vessel, said fixture being constructed for connection to the upper portion of the vessel, said fixture being constructed for receiving said substrate for said depending relation support; and wherein said fixture comprises an elongated well having a longitudinal interior chamber, said chamber being accessible through a port which extends through a proximal end of said well, said well having a distal end at which said chamber is closed, said well being constructed for anchoring to the inner surface of the top of the vessel in depending relation thereto, said well being further constructed such that said anchoring provides access to said chamber via said port from outside of the vessel and obstructs access to said chamber from inside of the vessel, said chamber being sized to receive said substrate to provide said depending relation support to said substrate, said substrate being thermally coupled to said well.