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:
Dec. 15, 1992
Filed:
Apr. 22, 1991
James F Pollock, Old Windsor, GB;
United Kingdom Atomic Energy Authority, London, GB;
Abstract
A filter unit (10) for removing particulates from exhaust gases for example from a diesel engine, includes several filter elements (24) arranged so the gas flows through them are in parallel and that no individual element carries more than a fifth of the total flow. Each element (24) comprises a tubular heating element (50) of high voidage electrically conducting material, with a secondary filter layer (52) adjacent to its upstream surface, and with means (53-63) to ensure the gas flow and particulate deposition are substantially uniform over the upstream surface. At intervals the heating elements (50) are electrically energized, in turn, to burn off deposited particulates. At any one time only a subset of the elements (24) is energized through which at that time no more than a fifth of the total gas flow passes. The unit (10) might have thirteen such elements (24), energized one at a time. Alternatively it might have fewer such elements (24) along with a valve to reduce the flow of gas through the element or elements which are at that time being energized.