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:
Oct. 03, 1978
Filed:
Jul. 05, 1977
Stuart A Hoenig, Tucson, AZ (US);
Ransburg Corporation, Indianapolis, IN (US);
Abstract
A simple, inexpensive, hand-held and operated apparatus for providing a substantially immediate indication of the density of, and charge on, airborne particulate contaminants of a predetermined size or within a predetermined size range includes a first filter for removing particulate contaminants having a size greater than the maximum size of the range, and a second filter for passing all particulate contaminants having size smaller than the minimum size of the range. The two filters are arranged in series in a housing, and a hand-operated pump having a known capacity is used to draw contaminant-laden air through the series filters. A conductive screen is placed against the second filter to provide an electrical indication of the polarity of the charge on the contaminants trapped by the second filter.