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:
Aug. 06, 2002
Filed:
Jan. 03, 2000
Ronald W. Lehman, Brooklyn Park, MN (US);
Gregory J. Engel, Plymouth, MN (US);
Tennant Company, Minneapolis, MN (US);
Abstract
A mobile debris collection machine which has an improved filter system includes a chassis, wheels for supporting the chassis, an operator controlled debris pickup on the chassis and a debris container on the chassis. There is a vacuum system for carrying debris from the pickup to the container, with the vacuum system including a vacuum fan located above the debris container for creating an air stream that moves dust and debris from the pickup toward the container. A filter system for removing dust and debris from the airstream includes a first filter stage formed of a rotating perforated member, a second filter stage that is located downstream of the vacuum fan and includes a mesh filter bag, and a third filter stage, located downstream from the second filter stage and including a pleated panel filter.