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. 13, 1990
Filed:
Nov. 10, 1988
Wayne M Wagner, Apple Valley, MN (US);
John A Campbell, Lakeville, MN (US);
William L Burchett, Grinnell, IA (US);
John S Wiese, Bloomington, MN (US);
John R Hiemstra, Apple Valley, MN (US);
Timothy A Bethke, Apple Valley, MN (US);
Donaldson Company, Inc., Minneapolis, MN (US);
Abstract
A muffler assembly includes an inner outlet tube having a tubular portion, a frusto-conical portion and a flange portion having an expanded orifice facing the outlet of an inlet tube. Both the outlet tube and inlet tube extend within a chamber defined in an outer housing. The chamber is divided into two or more subchambers by a baffle which extends between the outlet tube and the housing. One or more holes in the baffle improve the sound attenuation characteristics of the muffler. The invention also comprehends a novel blank used in forming the outlet tube, and three alternative methods which may be used to form the outlet tube.