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. 23, 2001
Filed:
Sep. 16, 1999
Bjorn von Palffy, South Beloit, IL (US);
Douglas M. Wallace, Roscoe, IL (US);
Jay D. Stradinger, Roscoe, IL (US);
Evac International Oy, Helsinki, FI;
Abstract
A vacuum drainage system having a vertical riser with an aeration point. The aeration point prevents stalls in the vacuum drainage system by breaking up the formation of a solid fluid column in the riser. In certain applications, the aeration point allows the vacuum drainage system to operate in a deliberately flooded condition by regulating air flow into the riser. The aeration point may be provided simply as a hole positions at an optimum height above a bottom of the riser, or it may include apparatus for retaining fluid inside the riser, such as a check valve. In addition, the aeration point may be provided with an automatically adjustable cross-section, so that aeration point is quickly and easily adapted to changing operating parameters in the vacuum drainage system.