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. 06, 1989
Filed:
Sep. 04, 1987
Richard J O'Brien, Burnsville, MN (US);
Douglas C Myhre, Eden Prairie, MN (US);
Rosemount Inc., Eden Prairie, MN (US);
Abstract
A purging air flow system for passing air over a lens to keep it clean and free from particulate contaminants and also for providing a positive flow of air away from the lens has baffles which cause a flow across the lens that is not symmetrical to avoid a dead air or stagnation zone in the center of the lens. The air supply used for such purging is controlled adequately so the flow changes direction and particles are removed from the main flow of purge air by inertial separation prior to the time the air contacts the lens. Such air entrained particles might otherwise deposit on the lens. A flow control orifice also may provide a secondary flow to carry the particles separated from the main flow out of the flow passageway.