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:
Nov. 25, 1980
Filed:
Jun. 30, 1978
A Clifton Lilly, Jr, Richmond, VA (US);
Warren E Claflin, Bon Air, VA (US);
William R Hardesty, Richmond, VA (US);
George R Scott, Mechanicsville, VA (US);
Roger L Hopkins, Richmond, VA (US);
Harry V Lanzillotti, Richmond, VA (US);
Philip Morris Incorporated, New York, NY (US);
Abstract
A web is electrically perforated at high hole density by applying alternating-current voltage across an electrode pair facing the web while pressurized gas is supplied to the electrode gap. Voltage amplitude level and gas flow and direction thereof are selected to provide for the striking of multiple arcs per half-cycle, thereby enabling reduction in spacing between adjacent perforations in the web. Perforation practice involving preselection of cigarette filter tipping paper based on chemical composition of the paper is also disclosed as is apparatus for use in implementing the described practices, wherein electrode support members have gas flow conduits formed integrally therewith and wherein webs are taken up by a capstan drive unit resiliently biased into engagement with a web take-up roll.