|Publication number||US20050050870 A1|
|Application number||US 10/763,646|
|Publication date||Mar 10, 2005|
|Filing date||Mar 3, 2003|
|Priority date||Mar 3, 2003|
|Also published as||CN1784257A, EP1601440A2, EP1601440A4, EP1601440B1, US7524360, US20060156702, WO2004078305A2, WO2004078305A3|
|Publication number||10763646, 763646, US 2005/0050870 A1, US 2005/050870 A1, US 20050050870 A1, US 20050050870A1, US 2005050870 A1, US 2005050870A1, US-A1-20050050870, US-A1-2005050870, US2005/0050870A1, US2005/050870A1, US20050050870 A1, US20050050870A1, US2005050870 A1, US2005050870A1|
|Original Assignee||Cheng Shi-Wai S.|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (13), Referenced by (3), Classifications (32), Legal Events (1)|
|External Links: USPTO, USPTO Assignment, Espacenet|
The present disclosure relates generally to an exhaust system, and particularly to a particulate filter for an exhaust system.
Automotive exhaust systems for diesel and other internal combustion engines typically include a filtration system that limits the mass of particulate matter emitted with the exhaust gases. In diesel engine systems, this matter typically includes carbonaceous matter (soot) and ash particles. Present filtering methods to trap the exhaust particulates focus on wall-flow filtration. Wall-flow filtration systems typically have a high filtration efficiency not only for exhaust particulates but also for ash particles. Catalytic or thermal arrangements within the exhaust system, which serve to effect regeneration of the filtration element, cannot remove ash particles, thereby increasing the accumulation of ash particles within the filtration body with time. In view of present particulate filter arrangements, it is desirable to have a more advanced particulate filter that can operate with effective filtration and with limited accumulation of ash particles over time.
In one embodiment, a particulate filter for an exhaust system configured to manage an exhaust flow includes a housing and a wall-flow filtration element contained within the housing. The wall-flow filtration element is configured to trap exhaust particulates and to pass ash particles.
In another embodiment, a particulate filter for an exhaust system configured to manage an exhaust flow includes a housing having a first end and a second end and a wall-flow filtration element arranged within the housing. The wall-flow filtration element includes a ceramic monolith structure having porous internal walls defining inlet and outlet channels, the inlet and outlet channels being separated by the porous internal walls to permit exhaust flow through the pores between the inlet and outlet channels. The inlet channels have inlet ports at one end and first end-plugs at the opposite end and are configured to receive the exhaust flow at the inlet ports, the inlet ports being arranged at the first end of the housing. The outlet channels have outlet ports at one end and second end-plugs at the opposite end and are configured to discharge the exhaust flow at the outlet ports, the outlet ports being arranged at the second end of the housing. The first end-plugs have greater porosity than the second end-plugs.
In a further embodiment, a method for filtering particulates of an exhaust flow of an exhaust system is disclosed. The exhaust flow is received at one end of a particulate filter having a ceramic monolith structure with porous walls defining inlet channels and outlet channels, the inlet channels each having an inlet port at one end to receive the exhaust flow and a porous plug at the opposite end, the outlet channels each having an outlet port at one end to discharge the exhaust flow and an end plug at the opposite end. The exhaust flow is filtered at the ceramic monolith structure as the exhaust flow passes through the porous walls between the inlet and outlet channels, exhaust byproducts are trapped at the porous walls, the end plugs, and the porous plugs, and ash particles are passed through the porous plugs. The exhaust flow is discharged at the outlet ports.
Referring to the exemplary drawings wherein like elements are numbered alike in the accompanying Figures:
An embodiment of the invention provides a particulate filter for an exhaust system of an automotive diesel engine. While the embodiment described herein depicts an automotive diesel engine as an exemplary diesel powerplant using a particulate filter, it will be appreciated that the disclosed invention may also be applicable to other diesel powerplants that require the functionality of the particulate filter herein disclosed, such as a diesel powered generator for example. While the disclosed invention is well suited for filtering the combustion byproducts of a diesel engine, it may also be applicable for filtering combustion byproducts of a gasoline powered engine.
An exemplary exhaust system 100 for an automotive diesel engine (not shown) is depicted in
Each particulate filter 200 has a housing 210, which may be any form of construction and configuration suitable for the purpose, and a filter element 220 suitably contained within housing 210, best seen by now referring to
Inlet channels 230 each have an inlet port 260 at one end 310 and a porous end-plug 270 at the opposite end 320. Outlet channels 250 each have an outlet port 280 at one end 320 and an end-plug 290 at the opposite end 310. Exhaust flow 150 enters filter element 220 at inlet ports 260, passes through porous internal walls 240, and is discharged from filter element 220 at outlet ports 280. In this manner, inlet channels 230 and outlet channels 250 are referred to as being in fluid communication with each other via internal walls 240. To facilitate the trapping of exhaust particulates and the leakage of ash particles at porous end-plugs 270 (the leakage of ash particles is depicted generally at arrows 340 in
In an embodiment depicted in
The process by which particulate filter 200 filters particulates from exhaust flow 150 of exhaust system 100 will now be described with reference to
In an embodiment, particulate filter 200 includes a known suitable heating means, such as electrical heater means or fuel burner means, not shown, to supply necessary heat to effect incineration of particles previously trapped by ceramic monolith structure 220 to effect regeneration thereof. Regeneration of ceramic monolith structure 220 serves to convert a substantial portion of the trapped exhaust particulates into ash particles for subsequent leakage through porous end-plugs 270.
Outlet channels 250 have outlet ports 280 at second end 320 to discharge exhaust flow 150 and end-plugs 290 at first end 310 to block the incoming exhaust flow 150. Exhaust flow 150 is filtered at the ceramic monolith structure 220 as it passes through the porous walls 240 between inlet and outlet channels 230, 250. Exhaust byproducts, such as metallic particles and carbonaceous matter, are trapped at porous walls 240, end-plugs 290, and porous end-plugs 270, whereas ash particles are passed, or more specifically leaked, through porous end-plugs 270. The filtered exhaust flow 150 is then discharged at outlet ports 280.
As discussed above, porous end-plugs 270 have a pore size equal to or greater than about 30 micrometers, and preferably have a pore size equal to or greater than about 30 micrometers and equal to or less than about 60 micrometers. Porous walls 240 and end-plugs 290, due to the pore size at those locations, do not permit leakage of ash particles, thereby trapping some of the ash particles within particulate filter 200.
As disclosed, an embodiment of the invention provides for ash leakage from particulate filter 200 through porous end-plugs 270, thereby reducing or negating the need for mechanical cleaning of the ash particles from the particulate filter 200.
While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.
|Cited Patent||Filing date||Publication date||Applicant||Title|
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|US4390355 *||Feb 2, 1982||Jun 28, 1983||General Motors Corporation||Wall-flow monolith filter|
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|Citing Patent||Filing date||Publication date||Applicant||Title|
|US7716921||Jan 19, 2006||May 18, 2010||Gm Global Technology Operations, Inc.||Exhaust particulate filter|
|US8011177||Aug 3, 2007||Sep 6, 2011||GM Global Technology Operations LLC||Exhaust particulate filter|
|WO2007027864A2 *||Aug 31, 2006||Mar 8, 2007||Gm Global Tech Operations Inc||Exhaust particulate filter|
|International Classification||B01D46/00, B01D46/24, C04B38/00, B01D, F01N3/022|
|Cooperative Classification||B01D46/2451, B01D46/2474, F01N3/0222, B01D46/2455, B01D53/9454, B01D2046/2437, B01D2046/2496, C04B2111/00793, Y02T10/20, B01D46/2459, B01D46/244, B01D2275/30, F01N2330/06, C04B38/0006, B01D2046/2433, F01N2330/60, Y10S55/10, Y10S55/05, Y10S55/30, Y02T10/22|
|European Classification||C04B38/00B, B01D53/94L4, B01D46/24F8D4, B01D46/24F8B4, B01D46/24F8D12, F01N3/022B|
|Feb 23, 2005||AS||Assignment|
Owner name: GENERAL MOTORS CORPORATION, MICHIGAN
Free format text: CORRECTIVE ASSIGNMENT TO CORRECT THE APPLICATION NUMBER PREVIOUSLY RECORDED ON REEL 014414 FRAME 406.;ASSIGNOR:CHENG, SHI-WAI S.;REEL/FRAME:015699/0412
Effective date: 20030307