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. 24, 1992
Filed:
Jun. 13, 1991
Oy Wartsila AB, Helsinki, FI;
Abstract
A vacuum sewer arrangement comprises a valve controlled air inlet duct to let air into the vacuum sewer at a position downstream of the sewer valve. The sewer valve can then be closed immediately after the sewage has passed into the vacuum sewer, because the air required for the sewage transport is received from the air inlet duct. Hence, the amount of air that flows into the sewer through the sewer valve when the sewer valve opens is small, and when the sewer valve is closed, air flows through the air inlet duct into the sewer, which reduces the pressure difference acting on the sewer valve. These measures tend to considerably reduce the noise level. In the case of a vacuum toilet sewer arrangement, the noise level can be further reduced by providing the toilet bowl with a lid forming a substantially airtight and soundproof closure at the top of the bowl. The volume of air contained in the bowl may be too small for proper discharge of the sewage, in which case additional air can be provided through a separate tube. This tube may be connected to the air inlet duct upstream of its valve.