The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 24, 2001
Filed:
Oct. 14, 1999
Charles Michael Birtcher, Valley Center, CA (US);
Thomas Andrew Steidl, Escondido, CA (US);
Martin Castaneda Martinez, Oceanside, CA (US);
Jamshid Jay Hamidi, Escondido, CA (US);
Air Products and Chemicals, Inc., Allentown, PA (US);
Abstract
A chemical delivery system for delivering chemicals having at least a high purity includes at least one first reservoir for containing a fluid and at least one second reservoir for containing the fluid. The system also includes a first conduit, a first fluid sensor, and a controller. The first conduit is for transferring the fluid over time from the at least one first reservoir to the at least one second reservoir. The first conduit is metallic and has a first end in communication with the at least one first reservoir and a second end in communication with the at least one second reservoir. The fluid being transferred from the at least one first reservoir to the at least one second reservoir flows through the first conduit from the first end to the second end. The first fluid sensor is adjacent the first conduit, and the first fluid sensor is adapted to detect a presence of the fluid and to detect an absence of the fluid in the first conduit. The first fluid sensor generates at least one first signal indicative of the presence of the fluid or the absence of the fluid. The controller receives the at least one first signal. The controller is adapted to identify an empty condition in the at least one first reservoir upon receiving the at least one first signal indicative of the absence of the fluid in the first conduit or upon not receiving at least one first signal indicative of the presence of the fluid in the first conduit.