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:
Jun. 30, 1987
Filed:
Jan. 13, 1986
Wayne M Wagner, Apple Valley, MN (US);
Timothy A Bethke, Apple Valley, MN (US);
Donaldson Company, Inc., Minneapolis, MN (US);
Abstract
The present invention is directed to providing an inexpensive, yet effective, simulation for measuring the sound level of the muffler contribution to the total sound created by a truck during a drive-by. The simulation method includes disconnecting a drive shaft of the drive mechanism of the truck and installing a dynamometer. When the throttle of the engine is increased, the dynamometer applies a load so that the acceleration rate of the drive mechanism compares similarly to the acceleration rates of a truck during an actual drive-by test in accordance with CFR 40, part 202. Sound barriers are placed around sounds sources other than the muffler of the truck. Microphones are used to sense the sound during the test for recording by strip-chart recorders.