Patent ID: 11899033
Assignee: LECO CORPORATION
Field: Measurement (Instruments)
Classification: CPC G  F | IPC F  G

Claim 17:
18. A thermogravimetric analyzer comprising:
a furnace having a base and a cover pivotally coupled to said base for movement between open and closed positions, wherein said base includes a carousel with a plurality of circular crucible-receiving apertures having one of two different diameters for receiving a plurality of crucibles positioned in said apertures of said carousel;
an access port formed in said cover and selectively aligned with one of said crucible-receiving apertures to allow a sample to be positioned from outside of the furnace into said one of said crucibles through said cover when said cover is in a closed position, wherein the access port has an opening smaller than an open mouth of the crucibles;
a heating element in said furnace;
a temperature control circuit for controlling the application of power to said heating element;
at least one temperature sensor positioned in said furnace for detecting the furnace temperature;
an electronic balance in said furnace for weighing said one of said crucibles in the carousel; and
a computer coupled to said temperature sensor and to said temperature control circuit to correlate temperatures during a cycle of operation of said furnace through increasing temperature steps to develop and store temperature control signals for controlling the application of power to said heating element, wherein the computer is coupled to said electronic balance to weigh said one of said crucibles throughout the cycle of operation to analyze the sample.