An exhaust manifold cooling jacket has internal passages for the circulation of liquid coolant and encloses an exhaust manifold such that a gap is created between the exhaust manifold and cooling jacket. Flowing coolant through the jacket regulates outer jacket temperature while enabling high intra-manifold exhaust gas temperatures for thorough intra-manifold combustion and improved emissions. A liquid-cooled exhaust system includes a turbocharger disposed between manifold and elbow, with liquid coolant flowing from manifold to elbow through the turbocharger. Another liquid-cooled exhaust manifold contains an internal exhaust combustion catalyst wrapped in an insulating blanket. In some marine applications, seawater or fresh water coolant is discharged into the exhaust gas stream at an attached exhaust elbow.
|
18. An exhaust manifold cooling jacket, comprising
a housing forming a cavity sized to enclose an exhaust manifold of a combustion engine with a gap therebetween, the housing defining a coolant inlet and a passage therethrough for the flowing of liquid coolant through the cooling jacket, and
a catalytic conversion element disposed within the housing.
1. An exhaust manifold cooling jacket comprising a housing to be attached to a cylinder head of a combustion engine, the housing defining
a cavity sized to enclose an exhaust manifold of the engine and form an insulating space between the exhaust manifold and housing, as attached to the cylinder head,
a coolant passage therein for receiving liquid coolant from an inlet of the jacket and for flowing the coolant through the cooling jacket,
an exhaust passage extending between an inner manifold interface surface of the housing and an exhaust elbow interface surface of the housing, for forming a sealed exhaust conduit for conducting a flow of exhaust from the exhaust manifold through the housing, and
a catalytic conversion element disposed within the housing.
14. A method of altering a combustion engine to enhance exhaust gas cooling for use in a marine environment, the method comprising the step of placing a cooling jacket directly between an upstream exhaust manifold secured to a cylinder head of the engine, and a downstream exhaust elbow of the engine, the cooling jacket comprising a housing defining
a cavity sized to enclose an exhaust manifold of the engine and form an insulating space between the exhaust manifold and housing, as attached to the cylinder head,
a coolant passage therein for receiving liquid coolant from an inlet of the jacket and for flowing the coolant through the cooling jacket,
an exhaust passage extending between an inner manifold interface surface of the housing and an exhaust elbow interface surface of the housing, for forming a sealed exhaust conduit from the exhaust manifold through the housing, and
a catalytic conversion element disposed within the housing.
2. The exhaust manifold cooling jacket of
3. The exhaust manifold cooling jacket of
4. The exhaust manifold cooling jacket of
5. The exhaust manifold cooling jacket of
6. The exhaust manifold cooling jacket of
7. The exhaust manifold cooling jacket of
8. The exhaust manifold cooling jacket of
9. The exhaust manifold cooling jacket of
10. The exhaust manifold cooling jacket of
11. The exhaust manifold cooling jacket of
12. The exhaust manifold cooling jacket of
13. The exhaust manifold cooling jacket of
15. The method of
16. The method of
17. The method of
19. The exhaust manifold cooling jacket of
20. The exhaust manifold cooling jacket of
|
This application claims priority from U.S. Provisional Application No. 60/206,050, filed May 22, 2000, which is incorporated herein by reference.
This invention relates to cooling engine exhaust manifolds and related components, and more particularly to controlling the temperature of engine exhaust components and the exhaust gasses flowing through them.
The exhaust gasses flowing through an exhaust gas manifold of an internal combustion engine are typically very hot, and the exhaust manifold itself may reach very high surface temperatures. To keep the outer surface temperature of the exhaust manifold down for safety reasons, some exhaust manifolds are water cooled, meaning that they contain inner passages through which cooling water flows during engine operation or that they are placed within jackets with cooling water flowing directly across the outer surface of the manifold. Indeed, there are some regulations requiring that exhaust manifolds be provided with cooling jackets for particular applications, such as for marine vessel inspections.
In one aspect, the invention features a cooling jacket having internal passages for flowing water or other coolant through the jacket to moderate jacket temperature. The jacket attaches to the engine cylinder head to enclose and cool the exhaust manifold of the engine, thereby moderating the temperature of the exhaust gas flowing through the manifold and blocking the outer surface of the manifold from unwanted contact with nearby objects or personnel. As the coolant flows through internal passages in the manifold rather than through or across the exhaust manifold, the coolant never comes into contact with the manifold itself. Manifold cooling is achieved via radiant and convective heat transfer to the jacket when an air gap is provided between the outer surfaces of the manifold and the inner surfaces of the cooling jacket, or by conduction through an insulating material placed between the manifold and jacket. Among the various aspects of the invention are the cooling jacket so described, engines equipped with such cooling jackets, and methods of cooling engine exhaust manifolds by incorporating such jackets.
In some embodiments the cooling jacket defines a coolant inlet and a coolant outlet that are both separate from the exhaust stream. In some other cases, particularly applicable to marine engines, for example, coolant enters the jacket through a separate inlet but then joins the exhaust flow as the exhaust leaves the manifold, thereby further reducing exhaust gas temperature.
In another aspect, the invention features a liquid-cooled turbocharger disposed between a liquid-cooled exhaust manifold and a liquid-cooled exhaust elbow, such that manifold cooling fluid flowing to the elbow flows through and cools the housing containing the turbocharger. Preferably, for marine applications, for instance, the cooling fluid is injected into the exhaust stream downstream of the turbocharger, such as in the elbow. In some cases, the manifold cooling fluid flows through the exhaust manifold itself. In some other cases, the fluid cools the manifold by flowing through a channel within a jacket that surrounds the manifold, as discussed above.
In some embodiments, the manifold houses an exhaust conversion catalyst. The exhaust conversion catalyst is arranged within the exhaust stream, such that the exhaust flows through the catalyst, and is isolated from the liquid coolant, which flows around the catalyst. Preferably, the flow of liquid coolant joins the flow of exhaust downstream of the catalyst. In some embodiments, an insulating blanket is placed between the catalyst and the manifold housing to help to insulate the hot catalyst from the surrounding housing, thereby promoting exhaust conversion and avoiding excessive external surface temperatures. The blanket can, in some cases, also help to protect fragile catalysts from shock damage.
In another aspect of the invention, a liquid-cooled exhaust manifold houses an exhaust conversion catalyst arranged within the exhaust stream, such that the exhaust flows through the catalyst, and is isolated from the liquid coolant, which flows around the catalyst. The manifold is adapted to receive and join separate flows of exhaust gas and direct them through the catalyst. The manifold comprises a one-piece housing, preferably of cast metal, forming the internal exhaust flow passages and cavity for receiving the catalyst.
Some aspects of the invention can provide for the ready modification of engines to comply with exhaust manifold cooling requirements, without having to modify the exhaust manifold to either provide for internal cooling or withstand prolonged surface contact with a desired coolant. Furthermore, the temperature of the exhaust gas within the manifold can be maintained at a higher temperature than with normally cooled manifolds, given a maximum allowable exposed surface temperature, enabling more complete intra-manifold combustion and improving overall emissions. Among other advantages, some aspects of the invention help to maintain high exhaust temperatures, such as to promote exhaust catalytic conversion, for example, without producing undesirably high external surface temperatures.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
Like reference symbols in the various drawings indicate like elements.
Referring first to
Referring also to
As shown in
Cooling jacket 20 may be east of any material suitable to the intended environment. For marine applications employing salt water as coolant, a salt resistant aluminum alloy is appropriate. If the cooling jacket is to be mounted directly against a cast iron engine head, or if very high temperatures are anticipated, cast iron may be more appropriate. If aluminum is used and exiting exhaust gas temperatures are high or the exhaust gas is particularly corrosive to aluminum, an iron sleeve may be provided through exhaust port 26.
To completely enclose the exhaust manifold, a backing plate 36 may be employed as shown in
Referring now to
Referring to
Referring next to
As shown in
Although not specifically illustrated, it should be understood from the above disclosure that another advantageous arrangement is to house an appropriately sized catalytic conversion element, such as element 68, within a manifold not adapted to circulate cooling fluid, and then surrounding the manifold with a secondary cooling jacket such as that shown in
Referring now to
A number of embodiments of the invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, a single manifold/jacket assembly may replace the standard exhaust manifold and contain both internal exhaust passages and internal coolant passages, with an internal air space between the coolant passages and exhaust passages such that many of the benefits of the invention are achieved. Because of direct exposure to high temperature exhaust gasses, however, such a combination version would be limited to particular materials, such as cast iron or steel. Accordingly, other embodiments are within the scope of the following claims.
Patent | Priority | Assignee | Title |
Patent | Priority | Assignee | Title |
4068612, | Jan 26 1976 | M & W Gear Company | Turbocharger housing construction for marine turbocharger and device for turbocharging a marine engine |
4091616, | Mar 04 1975 | Gewerkschaft Eisenhutte Westfalia | Catalytic devices for treating exhaust gases of internal combustion engines |
4214443, | Mar 31 1977 | Perkins Engines Limited | Marine engine manifold |
4273080, | Oct 06 1977 | Klockner-Humboldt-Deutz Aktiengesellschaft | Exhaust gas conduit system for multi-cylinder reciprocating piston internal combustion engines |
4463709, | Oct 06 1977 | Klockner-Humboldt-Deutz Aktiengesellschaft | Exhaust gas conduit system for multi-cylinder reciprocating piston internal combustion engines |
4987953, | Mar 09 1990 | Kohler Company | Shared coolant system for marine generator |
4991546, | Jul 05 1988 | SANSHIN KOGYO KABUSHIKI KAISHA, D B A SANSHIN INDUSTRIES CO , LTD , A CORP OF JAPAN | Cooling device for boat engine |
5058660, | Mar 09 1990 | Kohler Co. | Shared coolant system for marine generator |
5067448, | Sep 27 1988 | SANSHIN INDUSTRIES CO , LTD , A CORP OF JAPAN | Exhaust cooling device for small sized boat engine |
5203167, | Oct 25 1991 | BRP US INC | Marine propulsion device internal combustion engine and method for making the same |
5212949, | May 22 1990 | Sanshin Kogyo Kabushiki Kaisha | Exhaust gas cleaning system for a marine propulsion unit |
5239825, | Feb 13 1991 | Sanshin Kogyo Kabushiki Kaisha | Exhaust emission control device for outboard motor |
5253613, | Apr 30 1992 | GENERAL ELECTRIC COMPANY, A CORP OF NY | High power AC traction inverter cooling |
5272874, | Sep 26 1991 | ALPHA COAL WEST, LLC AS SUCCESSOR BY CONVERSION TO ALPHA COAL WEST, INC ; ALPHA AMERICAN COAL COMPANY, LLC; DFDSTE, LLC AS SUCCESSOR BY CONVERSION TO DFDSTE CORP , F K A DRY SYSTEMS TECHNOLOGIES, INC | Exhaust treatment system |
5311738, | Feb 28 1992 | MTU Motoren- und Turbinen- Union Friedrichshafen GmbH | Exhaust gas duct for a row of cylinders of an internal combustion engine |
5408827, | Sep 28 1993 | BRP US INC | Marine propulsion device with improved catalyst support arrangement |
5463867, | Dec 14 1993 | MTU Motoren- und Turbinen-Union Friedrichshafen GmbH | Supercharged internal combustion engine exhaust system |
5488826, | Sep 26 1991 | ALPHA COAL WEST, LLC AS SUCCESSOR BY CONVERSION TO ALPHA COAL WEST, INC ; ALPHA AMERICAN COAL COMPANY, LLC; DFDSTE, LLC AS SUCCESSOR BY CONVERSION TO DFDSTE CORP , F K A DRY SYSTEMS TECHNOLOGIES, INC | Heat isolated catalytic reactor |
5546748, | Nov 27 1992 | Sanshin Kogyo Kabushiki Kaisha | Exhaust system for outboard motor |
5619956, | Jul 15 1993 | CUMMINS POWERGEN IP, INC | Auxiliary power unit for hybrid electric vehicle |
5829249, | Jan 19 1996 | BRP US INC | Internal combustion engine with exhaust passage and reactor having a common wall |
5873330, | Dec 30 1995 | SANSHIN KOGYO KABUSHIKI KAISH; Sanshin Kogyo Kabushiki Kaisha | Cooling arrangement for engine |
5899063, | Nov 23 1994 | Tezet-Service AG | Water-cooled catalyst system |
5911608, | Nov 13 1992 | United Technologies Corporation | Exhaust system for outboard motors |
6155896, | Oct 06 1997 | Yamaha Hatsudoki Kabushiki Kaisha | Exhaust system and control for watercraft |
6360702, | Nov 10 1999 | Isuzu Motors Limited | EGR and oil cooling system |
DE2345383, |
Executed on | Assignor | Assignee | Conveyance | Frame | Reel | Doc |
Date | Maintenance Fee Events |
Date | Maintenance Schedule |
Nov 29 2008 | 4 years fee payment window open |
May 29 2009 | 6 months grace period start (w surcharge) |
Nov 29 2009 | patent expiry (for year 4) |
Nov 29 2011 | 2 years to revive unintentionally abandoned end. (for year 4) |
Nov 29 2012 | 8 years fee payment window open |
May 29 2013 | 6 months grace period start (w surcharge) |
Nov 29 2013 | patent expiry (for year 8) |
Nov 29 2015 | 2 years to revive unintentionally abandoned end. (for year 8) |
Nov 29 2016 | 12 years fee payment window open |
May 29 2017 | 6 months grace period start (w surcharge) |
Nov 29 2017 | patent expiry (for year 12) |
Nov 29 2019 | 2 years to revive unintentionally abandoned end. (for year 12) |