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:
Apr. 03, 2001
Filed:
Apr. 29, 1997
Robert Guy Garber, San Jose, CA (US);
Other;
Abstract
A multiple cartridge filter housing assembly for the high purity filtration of etching liquids, deionized water, slurries and other liquids used in the semiconductor, pharmaceutical and chemical industries. It comprises at least one upper and one lower cartridge within a bottom housing, a top housing and at least one extension housing. A vent tube in the top housing extending to the upper spacer ring in the extension housing generates a first air pocket between its lower end and the top of the housing assembly. The upper end of each cartridge is centered by a flow-through spacer ring. The lower end of each cartridge is sealed, against the pressure drop across the cartridge, and centered by an adapter ring. The adapter rings, except for the bottom one, have a downwardly extending tube with flow-through holes at its lower end such that secondary air pockets are generated above the holes and below the bottom surface of the adapter ring. The first and the second air pockets are in series allowing for multi-dampening of pressure variations in the liquid within and exiting the housing assembly. Nut rings with tension rings at each interface between housing components provide reliable seals inspite of temperature cycling.