Chemical refill system for high purity chemicals
Patent 5607002 Issued on March 4, 1997. Estimated Expiration Date: 
November 28, 2014. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
November 28, 2014. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 2160062 2536273 2777914 3419695 3646293 3731805 3826139 Liquid level sensor Liquid level sensor Liquid source material container and method of use for semiconductor device manufacturing InventorsAssigneeApplicationNo. 345244 filed on 11/28/1994US Classes:141/198, Level or overflow responsive73/308, Electric73/311, Multiple floats73/313, With electrically controlled indicator73/319, Vertically reciprocable137/209, With gas maintenance or application137/412, Servo relay operation of control141/95, Level or pressure in receiver200/84CMagnetExaminersPrimary: Jacyna, J. CasimerAttorney, Agent or FirmForeign Patent References
International ClassF17C 013/00AbstractA highly reliable digital level sensor assembly is provided to replace optical and capacitance type sensors in high purity chemical delivery systems. The digital level sensor assembly is particularly useful in bulk chemical refill delivery systems for high purity chemicals employing a manifold that ensures contamination free operation and canister change outs with a minimum of valves and tubing.Other References
Field of SearchBy operation of means causing or controlling dispensingFLUENT CHARGE IMPELLED OR FLUID CURRENT CONVEYED INTO RECEIVER Level or pressure in receiver Level or overflow responsive Plural units With gas maintenance or application Servo relay operation of control Electric Multiple floats With electrically controlled indicator Vertically reciprocable Float sensor Vertically reciprocable Magnet | |
