Access port for a thermogravimetric analyzer furnace
AssigneeLeco Corporation
InventorLarry S. O'Brien
Life of this patent
Estimating the term…
Abstract
The analyzer of the present invention is specifically adapted to provide moisture determinations for foods and other agricultural material. It allows the operator to introduce a precise weight of sample into a crucible in a closed furnace in a controlled environment through an access port in the furnace cover. The access port in the cover can be tapered to allow easy access to an underlying aligned crucible and allow an operator to add and remove sample material from the crucible until a precise desired sample weight is reached as measured by a balance within the furnace. The access port is enclosed by an insulated cover after the samples are sequentially placed in the crucibles.
Claims22
A furnace for a thermogravimetric analyzer, said furnace comprising:
- a base including a rotatable carousel having a plurality of apertures for receiving crucibles;
- a cover movably coupled to said base for movement between open and closed positions to selectively allow access to said carousel;
- a heating element in at least one of said base and cover for heating samples positioned in crucibles;
- and
- said cover including an access port aligned with at least one of said crucible-receiving apertures to allow an operator to position sample material in at least one crucible through said access port when said cover is in a closed position, wherein the access port has an opening that is smaller than the apertures in the carousel that receive the crucibles.
A furnace comprising:
- a base including a rotatable disk-shaped carousel having a plurality of apertures for receiving and holding crucibles;
- a cover coupled to said base and movable between open and closed positions for selectively allowing access to said carousel;
- a heating element in at least one of said base and cover for heating samples to be analyzed placed in one or more crucibles positioned in said crucible-holding apertures of said carousel;
- and
- wherein said cover includes an access port dimensioned to allow an operator to add sample material to a crucible positioned in a crucible-holding aperture of said carousel with said cover in a closed position, said access port selectively aligned with one or more crucible-receiving apertures in said carousel to allow an operator to position sample material in a crucible through said access port, wherein the access port has an opening that is smaller than the apertures in the carousel that receive the crucibles.
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.
Dependencies are inferred from the claim text.