Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
  • F02M26/42—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories having two or more EGR passages; EGR systems specially adapted for engines having two or more cylinders
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B47/00—Methods of operating engines involving adding non-fuel substances or anti-knock agents to combustion air, fuel, or fuel-air mixtures of engines
  • F02B47/04—Methods of operating engines involving adding non-fuel substances or anti-knock agents to combustion air, fuel, or fuel-air mixtures of engines the substances being other than water or steam only
  • F02B47/08—Methods of operating engines involving adding non-fuel substances or anti-knock agents to combustion air, fuel, or fuel-air mixtures of engines the substances being other than water or steam only the substances including exhaust gas
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
  • F02F1/00—Cylinders; Cylinder heads 
  • F02F1/18—Other cylinders
  • F02F1/22—Other cylinders characterised by having ports in cylinder wall for scavenging or charging
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
  • F02M26/17—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories in relation to the intake system
  • F02M26/20—Feeding recirculated exhaust gases directly into the combustion chambers or into the intake runners
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
  • F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
  • F02M26/37—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with temporary storage of recirculated exhaust gas
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
  • F02M26/41—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories characterised by the arrangement of the recirculation passage in relation to the engine, e.g. to cylinder heads, liners, spark plugs or manifolds; characterised by the arrangement of the recirculation passage in relation to specially adapted combustion chambers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
  • F02B75/00—Other engines
  • F02B75/02—Engines characterised by their cycles, e.g. six-stroke
  • F02B2075/022—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle
  • F02B2075/025—Engines characterised by their cycles, e.g. six-stroke having less than six strokes per cycle two
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/10—Internal combustion engine [ICE] based vehicles
  • Y02T10/12—Improving ICE efficiencies

Definitions

• This invention relates to internal combustion engines and particularly internal combustion engines operating on the two stroke cycle and to the management of the combustion process thereof to control the level of contaminants in the exhaust emissions.
• the disclosed method of operating a two stroke cycle crankcase scavenged internal combustion engine comprises selectively delivering exhaust gas from a location downstream of the engine exhaust port directly into the engine crankcase to be delivered together with air in the crankcase to the engine combustion chamber, and controlling the quantity of exhaust gas delivered to the crankcase each engine cycle in accordance with engine operating conditions.
• the exhaust gas is taken from the exhaust system downstream of the exhaust port and thus usually requires some form of external componentry to take the already exhausted gas and reintroduce this gas either indirectly or directly into one or more combustion chambers of the engine.
• This arrangement normally requires some form of external duct work to direct a portion of the exhaust gas into the fresh air or air and fuel charge for admission therewith into one or more combustion chambers of the engine.
• Such constructions represent an additional cost arising from the necessity to manufacture additional componentry and to subsequently assemble same to the engine block and its ancillaries. Thus, additional manufacturing and installation costs are incurred.
• each of the above referred to pending patent applications propose the introduction of the exhaust gas to the combustion chamber of a two stroke cycle engine via the engine crankcase.
• each proposal involves exposing the environment within the crankcase to exhaust gas which, under certain circumstances or conditions, may lead to adverse effects in engine operation and/or durability of components such as reed valves, the crankshaft and connecting rod bearings.
• a method of operating an internal combustion engine having a plurality of cylinders and pistons respectively supported therein said method including communicating at least one cylinder during an expansion stroke of the piston therein with at least one other cylinder of the engine during a compression stroke of the piston therein, said communication being effected when the pressure differential in the communicating cylinders establishes a flow of combusted gas from the at least one cylinder to the at least one other cylinder.
• the communication is preferably independent of an exhaust system of the engine.
• each cylinder of the engine is arranged to supply combusted gas to a first said cylinder and receive combusted gas from a second said cylinder.
• the above method may also conveniently include the step of cooling the combusted gas during transfer thereof.
• an internal combustion engine having a plurality of cylinders and pistons respectively supported therein, the engine including means arranged to provide communication between at least one cylinder and at least one other cylinder, whereby combusted gas from the at least one cylinder during an expansion stroke of the piston therein is passed to the at least one other cylinder during a compression stroke of the piston therein due to the pressure differential therebetween.
• the communication between the cylinders is preferably independent of an exhaust system of the engine.
• each cylinder of the engine communicates with two other cylinders for providing combusted gas to one of the cylinders and for receiving combusted gas from the other one of the cylinders.
• each said cylinder has a port in the wall thereof communicating with a port in the wall of another cylinder, said ports being located in the respective cylinders so that during the expansion stroke of the piston within one of said cylinders, combusted gas passes to another of said cylinders during the compression stroke of the piston therein.
• the communication between respective cylinders is provided by at least one conduit which, at the respective ends thereof, communicates with the ports in the cylinder walls at different levels in respect to the travel of the piston within the cylinders.
• At least one cylinder may be arranged to deliver combusted gas during the respective expansion stroke of the piston therein to a gallery or passage which is in turn connected to at least one other cylinder at a location of lower pressure during the cycle of operation thereof so that combusted gas can pass from the gallery or passage into said at least one other cylinder.
• suitable ports are provided in the wall of each cylinder for the supply of combusted gas to the gallery or passage, and further ports are provided in the wall of each cylinder for the discharge of combusted gas from the gallery or passage to each cylinder.
• the ports of each cylinder may be located at different levels in respect to the travel of the piston within the cylinder.
• the combusted gas is subject to a degree of cooling. This may be achieved by locating the gallery or the passage conveying the combusted gas adjacent the cooling system of the engine and/or by providing specific cooling to the passages, ducts or galleries, by cooling means such as cooling fins on the periphery thereof, or a specific jacket through which a cooling medium such as water or air is passed.
• individual valve means may be provided on the respective ports or on one of each two intercommunicating ports.
• a common duct or gallery is used to receive and/or supply combusted gas to or from more than one cylinder, it may be necessary to provide appropriate valves associated therewith or like controls that may be selectively operated to provide communication between the passage or gallery and the respective cylinders supplying or receiving combusted gas.
• the valves may be appropriate pressure activated valves or may be of the controlled type such as by a programmed electronic control mechanism.
• the method and apparatus disclosed herein for providing combusted gas to the cylinders of a multi-cylinder engine as a means of controlling the combustion process of the engine and thereby reducing undesirable emissions such as NO ⁇ has the advantage that it is independent of the engine exhaust system and that the combusted gases do not come in contact with areas of the mechanisms of the engine which may be adversely affected by the presence of combusted gas such as the air control system in the air intake duct and reed valves, bearings and other components in the case of crankcase scavenged two stroke cycle engines.
• the method and apparatus as disclosed herein may be used exclusively to recycle combusted gas to the combustion chambers of an engine for the purposes of emission control or it may be used in conjunction with other forms of exhaust gas recirculation such as those disclosed in the pending applications of the applicant as identified hereinbefore or any other form of exhaust gas recirculation.
• Figure 1 is a series of schematic representations of a three cylinder two stroke cycle engine showing the interconnection between respective cylinders
• Figure 2 is a diagrammatic representation of a flattened engine cylinder showing the port location therein.
• the engine cylinders are designated 1 , 2 and 3, and it is to be understood that the pistons of the respective cylinders numbered 4, 5 and 6 are connected to a common crankshaft (not shown) in the conventional manner and are respectively 120° out of phase with each other about the axis of the crankshaft.
• a and B which hereinafter, shall be identified by the combined notation of the cylinder and the port notation, thus, in cylinder 1 the ports will be identified as 1A and 1 B, in cylinder 2, 2A and 2B and in cylinder 3, 3A and 3B.
• the ports A and B are displaced from one another in the direction of the axis of the cylinders 1 ,2,3 and thus, as the pistons 4,5,6 move down from the top dead centre position, the port A will firstly be uncovered so as to provide communication with the area of the cylinders 1 ,2,3 above the level of the pistons 4,5,6 and at a later point in the piston travel, the port B will be exposed and communicated with the combustion chamber above the level of the pistons 4,5,6.
• the port A is located above the level of both the exhaust port 10 and the main and auxiliary transfer ports 11 and 12 of the cylinders 1 ,2,3 and accordingly, the port A will be exposed for communication with the combustion chamber prior to the commencement of the exhaust of the combustion gases through the exhaust port 10, and also prior to the opening of the main and auxiliary transfer ports 11 and 12.
• the port B is located so that it will be in communication with the combustion chamber whilst the exhaust port 10 and transfer ports 11 and 12 are also in communication with the combustion chamber. However, the port B will be closed prior to the closing of the exhaust 10 and transfer ports 11 and 12. Both the port A and B are located on the side of the cylinders 1 ,2,3 opposite the exhaust port 10.
• the three representations X, Y and Z of the three cylinder engine as shown in Figure 1 represent respectively the relative disposition of the respective pistons 4,5,6 of the engine when they are in their top dead centre position, that is, in X, the piston 4 is at the top dead centre position in cylinder 1 , in Y, the piston 5 is at the top dead centre position in cylinder 2, and in Z, the piston 6 is at the top dead centre position in cylinder 3.
• the communicating passages 7,8 and 9 between the respective ports A and B are only shown in configurations X, Y and Z where the ports A and B at the respective ends of the passages 7,8,9 are exposed and thus combustion gas is flowing therealong.
• port 3A is in communication with port 2B via the passage 7 thereby permitting combustion gas to flow from cylinder 3 to cylinder 2.
• the ports 1 A and 3B are in communication via the passage 8 with the gas flowing from cylinder 1 to cylinder 3.
• port 2A is in communication with port 1 B whereby combustion gas passes from cylinder 2 to cylinder 1 via the passage 9.
• each of the passages 7, 8 and 9 may be appropriate to incorporate in each of the passages 7, 8 and 9 a control valve to enable a further control to be exercised over the duration and/or timing of the flow of gases between the cylinders 1,2,3 connected by the respective passages 7,8,9.
• appropriate valves would be incorporated in the passages 7, 8 and 9, these being under the control of an ECU programmed in accordance with the required timing and duration of the communication.
• two or more of the ports A and B may be in communication with a distribution gallery to permit the required flow of combustion gas to the respective cylinders 1 ,2,3 prior to commencement of combustion therein.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Exhaust-Gas Circulating Devices (AREA)
• Output Control And Ontrol Of Special Type Engine (AREA)
• Combustion Methods Of Internal-Combustion Engines (AREA)

Applications Claiming Priority (3)

Publications (2)

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ID=3776942

Family Applications (1)

Country Status (7)

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Family Cites Families (3)

• 1994
  • 1994-05-25 EP EP94916093A patent/EP0702751A4/de not_active Withdrawn
  • 1994-05-25 KR KR1019950704881A patent/KR960702057A/ko not_active Withdrawn
  • 1994-05-25 CN CN94191859A patent/CN1121741A/zh active Pending
  • 1994-05-25 CA CA002162038A patent/CA2162038A1/en not_active Abandoned
  • 1994-05-25 JP JP7500019A patent/JPH08510315A/ja active Pending
  • 1994-05-25 WO PCT/AU1994/000270 patent/WO1994028300A1/en not_active Ceased
  • 1994-05-25 BR BR9406286A patent/BR9406286A/pt not_active Application Discontinuation

Non-Patent Citations (2)

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