GB2093909A - I.C. engines operable on less than all cylinders - Google Patents
I.C. engines operable on less than all cylinders Download PDFInfo
- Publication number
- GB2093909A GB2093909A GB8105242A GB8105242A GB2093909A GB 2093909 A GB2093909 A GB 2093909A GB 8105242 A GB8105242 A GB 8105242A GB 8105242 A GB8105242 A GB 8105242A GB 2093909 A GB2093909 A GB 2093909A
- Authority
- GB
- United Kingdom
- Prior art keywords
- chambers
- subset
- gas
- combustion
- inlet
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D21/00—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas
- F02D21/06—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air
- F02D21/08—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air the other gas being the exhaust gas of engine
-
- 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
- F02B75/16—Engines characterised by number of cylinders, e.g. single-cylinder engines
- F02B75/18—Multi-cylinder engines
- F02B75/22—Multi-cylinder engines with cylinders in V, fan, or star arrangement
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D17/00—Controlling engines by cutting out individual cylinders; Rendering engines inoperative or idling
- F02D17/02—Cutting-out
- F02D17/023—Cutting-out the inactive cylinders acting as compressor other than for pumping air into the exhaust system
- F02D17/026—Cutting-out the inactive cylinders acting as compressor other than for pumping air into the exhaust system delivering compressed fluid, e.g. air, reformed gas, to the active cylinders other than during starting
-
- 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
- F02M26/43—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 in which exhaust from only one cylinder or only a group of cylinders is directed to the intake of the engine
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D9/00—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
- F02D9/02—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits concerning induction conduits
- F02D2009/0201—Arrangements; Control features; Details thereof
- F02D2009/0272—Two or more throttles disposed in series
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Output Control And Ontrol Of Special Type Engine (AREA)
Abstract
At partial loads and low speeds fuel is cut off from the cylinders D and the air from these cylinders is supplied to the cylinders A, or mixed with the exhaust gases from the cylinders A. Alternatively, exhaust gases from the cylinders A are supplied to the cylinders D and the exhaust gases from these cylinders may be mixed with the remaining exhaust gases from the cylinders A, Figs. 3 and 4 (not shown). <IMAGE>
Description
SPECIFICATION
Internal combustion engine
This invention relates to internal combustion engines.
In order to improve the fuel economy in 2-or 4 stroke internal combustion engines comprising an engine block a plurality of pistons and cylinders defining a set of at least two combustion chambers, each having an inlet for intake gas and an outlet for exhaust gas, it is known to include selector means in the engine for selectively preventing the supply of fuel to a first subset of the chambers, comprising at least one of the chambers, whereby combustion occurs only in a second subset of chambers, comprising the remaining chamber of chambers. This selector means is usually actuated when the engine is operating at less than full speed and under less than full load, so that the second subset of chambers takes the full load of the engine, with a resulting decrease in fuel consumption without loss of power.
We have found that such selective deactivation of some of the combustion chambers if often accompanied by an increase in the level of hydrocarbons and oxides of nitrogen in the exhaust gases.
According to the present invention, there is provided an internal combustion engine comprising an engine block, a plurality of piston and cylinders defining a set of combustion chambers each having an inlet for intake gas and an outlet for exhaust gas, means for supplying fuel and air to each inlet, and selector means for selectively preventing the supply of fuel to a first subset of chambers comprising at least one of the chambers whereby combustion occurs only in a second subset of chambers comprising the remaining chamber or chambers, characterised by means for purging volatile material from the first subset of chambers with gas, and for heating the said material by contact with gaseous combustion products from the second subset of chambers during or immediately after formation.
By purging volatile material such as hydrocarbon produced by volatilisation of lubrication oil within the second subset of chambers and decomposing this material by contact with the newly formed combustion gases, the level of noxious products in the exhaust gases is reduced.
The purging and heating may be effected in a number of different ways. For example gas from the outlet of either one of the subsets of chambers may be directed into the inlet of the other subset of chambers. If gas from the outlet of the first subset of chambers (i.e. the deactivated chambers) is directed into the inlet of the second subset of chambers (the active chambers) the volatile materials are purged from the first subset of chambers with air and are heated during the combustion process within the first combustion chambers. If gas from the outlet of the activated chambers is directed into the inlet of the deactive chambers, the volatile material is simultaneously heated and purged from the deactivated chambers by the newly formed exhaust gases from the active chambers.This latter system has the advantage that the exhaust gases maintain the deactivated chambers at a high temperature.
Additionally, or alternatively, the volatile material purged from the second by air or by exhaust gases may be heated by mixing gas from the outlets from the two subsets of chambers immediately downstream of the outlet from the second set of chambers.
The means for directing the gas between the two subsets of chambers will normally comprise a conduit interconnecting the outlet or outlets of the first subset of chambers and the inlet or inlets to the second subset of chambers, and a valve for controlling the flow of gas therethrough, the said valve being operable in synchronism with the selector means.
Embodiments of the invention will now be described, by way of example only with reference to the accompanying schematic drawings in which:
Figure 1 and 2 represent engines in accordance with one aspect of the invention,
Figure 3 and 4 represent engines in accordance with another aspect of the invention, and
In the drawings similar parts are identified by like reference numerals.
Referring to Figures 1 and 2, Fig. 1 shows an engine having an engine block 1 which includes six pistons and cylinders defining a set of six similar combustion chambers 2 arranged in a conventional V configuration to form two subsets
A, D of three chambers. Each combustion chamber 2 has an inlet 3, for intake gas, and an outlet 4, for exhaust gas, the inlets and outlets of each subset being connected in common by manifolds 5, 6, 7, 8. The two inlet manifolds 6, 7 are fed from supply lines 9, 10 and the two exhaust manifolds, 5, 8 discharge exhaust lines 11, 1 2. The exhaust manifold 8 from a first subset of chambers D, is also connected by a conduit 13 to the supply line 9 of the second subset of chambers A. This conduit 13 is opened and closed by a valve 14.
When the engine is operating under full load or at high speed, the valve 14 is closed and the inlet 3 to all the cylinders are supplied with fuel and air.
At partial loads and low speeds, however a selector (not shown) of conventional construction operated to prevent the supply of fuel to the inlets to the first subset of chambers, D. At the same time the valve 14 is opened. The second subset of chambers A continues to be supplied with fuel and air. As a result, the load on the second subset of chambers A is increased, arid the engine continues to operate at the same power level but with a reduced fuel consumption. The air supplied to the first subset of chambers D along the supply line 10
reduces pumping losses across the carburettor throttle and avoids undesirably high vacuum levels
in the intake manifold of the first subset of
chambers D, which would increase consumption
of oil in the engine.
The air passing through the first subset of chambers D purges volatile materials such as lubricating oil hydrocarbons from the chambers D.
These materials are passed into the first set of chambers A where they are heated during the combustion process. This contact with the combustion gases in the active chambers breaks down or burns the volatile material so that they do not contaminate the exhaust gases.
In an alternative arrangement, the conduit 13 and the valve 14 are dispensed with, and the gases from the outlet of the first set of combustion chambers D is diverted through a control valve 14' along branch 1 5 of the exhaust line to contact the gaseous combustion products produced in the second set of chambers immediately downstream from the outlets therefrom. The temperature of the combustion products in the immediate vicinity of the outlets to break down the volatile material spurged from the first set of chambers D.
Figure 2 illustrates similar arrangements to those described with reference to Figure 1 for a 4cylinder engine in which the cylinders 2 are arranged in line. The operation of this engine is similar to that of Figure 1.
Referring to Figure 3, an engine similar to that of Figure 1 is illustrated. The'difference between the two engines is that the conduit 13 and valve 14 are replaced by a conduit 20 which interconnects the exhaust line 11 from the second subset of chambers A with the supply line 10 to the first subset of chambers D, this conduit being opened and closed by a valve 21. In addition a further valve 22 is provided in the supply line 10 to prevent passage of air into the first subset of chambers D along the line 10. If desired, an exhaust gas recirculation (EGR) passage 23 (or 23') controlled by a conventional exhaust gas recirculation valve (not shown) may be provided between the two supply lines 9, 10 downstream of the valve 14 to allow exhaust gas from the conduit 20 to pass into the supply line 10.
In operation, under high load or high speed conditions, the valve 21 and the EGR passage 23 (or 23') are closed and the further valve 22 is opened so that all the chambers 2 are supplied with a mixture of air and fuel.
Volatile material, such as lubricating oil hydrocarbons, is therefore purged from the first subset of chambers D and simultaneously heated by the combustion products from the second subset of chambers A. Since the combustion products are newly formed, they heat the volatile material to a temperature sufficiently high to break them down, thereby reducing contamination in the exhaust gases from the engine. The supply of hot combustion products to the deactivated chambers
has the additional advantage that the second subset of chambers D is maintained at a high temperature so that combustion occurs efficiently as soon as the supply of fuel to the second subset of chambers D is restored. Friction on the chambers D is also reduced.
If desired, the engine may be modified so that the gases emerging from the first subset of chambers D are mixed with excess exhaust gases from the second subset of chambers A immediately downstream from the outlet therefrom by passing the gases from the first subset of chambers D through a branch 1 5 of the exhaust line 12, which is opened and closed by a valve 14' in synchronism with the other valves 21, 22. The volatile material purged from the first subset of chambers D is therefore subjected to two heating operations.
Figure 4 illustrates an arrangement similar to
Figure 3 for a 4-cylinder engine in which the combustion chambers are arranged in one line.
Claims (7)
1. An internal combustion engine comprising an engine block, a plurality of piston and cylinders defining a set of combustion chambers each having an inlet for intake gas and an outlet for exhaust gas, means for supplying fuel and air to each inlet, and selector means for selectively preventing the supply of fuel to a first subset of chambers comprising at least one of the chambers whereby combustion occurs only in a second subset of chambers comprising the remaining chamber or chambers, characterised by means for purging volatile material from the first subset of chambers with gas, and for heating the said material by contact with gaseous combustion products from the second subset of chambers during or immediately after formation.
2. An internal combustion engine according to claim 1 wherein the means for purging the said material from the second subset of chambers comprises means for directing gas from the outlet of one of the subsets of chambers into the inlet to the other subset of chambers.
3. An engine according to claim 2 wherein the said one subset comprises the first subset of chambers and comprising air.
4. An engine according to Claim 2 wherein the said one subset comprises the second subset of chambers, the gas comprising combustion exhaust products.
5. An engine according to any one of claims 2 to 4 wherein the said means for directing gas comprises a conduit interconnecting the outlet of the first subset of chambers with the inlet to the second subset of chambers and a valve for controlling the flow of gas therethrough, the said valve being operable in synchronism with the selector means.
6. An engine according to any one of claims 1 to 5 wherein the means for purging the first subset of chambers comprises means for mixing gas from the outlets of the two subsets of chambers immediately downstream of the outlet from the second subset of chambers.
7. An internal combustion engine substantially
as hereinbefore described, and as illustrated in any one of Figures 1 to 5 of the drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8105242A GB2093909A (en) | 1981-02-19 | 1981-02-19 | I.C. engines operable on less than all cylinders |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8105242A GB2093909A (en) | 1981-02-19 | 1981-02-19 | I.C. engines operable on less than all cylinders |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB2093909A true GB2093909A (en) | 1982-09-08 |
Family
ID=10519819
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8105242A Withdrawn GB2093909A (en) | 1981-02-19 | 1981-02-19 | I.C. engines operable on less than all cylinders |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2093909A (en) |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1988002065A1 (en) * | 1986-09-13 | 1988-03-24 | Mtu Motoren- Und Turbinen-Union Friedrichshafen Gm | Multi-cylinder diesel internal combustion engine with low compression ratio in the cylinders |
| WO2001044650A1 (en) * | 1999-12-17 | 2001-06-21 | Mtu Friedrichshafen Gmbh | Exhaust gas recirculation device |
| GB2371087A (en) * | 2000-11-20 | 2002-07-17 | Ford Global Tech Inc | A supercharged engine where cylinders in non-firing mode provide compressed air to the firing cylinders |
| GB2418228A (en) * | 2004-09-21 | 2006-03-22 | Lotus Car | Multiple combustion chamber internal combustion engine with a combustion chamber deactivation system |
| FR2885177A1 (en) * | 2005-04-27 | 2006-11-03 | Renault Sas | Internal combustion engine e.g. diesel engine, has air intake circuit allowing air into combustion cylinders, where part of air flow is aspirated by recirculation cylinder via conduit placed downstream of recirculation cylinder |
| US7765994B2 (en) | 2007-07-12 | 2010-08-03 | Ford Global Technologies, Llc | Cylinder charge temperature control for an internal combustion engine |
| US7779823B2 (en) | 2007-07-12 | 2010-08-24 | Ford Global Technologies, Llc | Cylinder charge temperature control for an internal combustion engine |
| US7801664B2 (en) | 2007-07-12 | 2010-09-21 | Ford Global Technologies, Llc | Cylinder charge temperature control for an internal combustion engine |
| US8020525B2 (en) | 2007-07-12 | 2011-09-20 | Ford Global Technologies, Llc | Cylinder charge temperature control for an internal combustion engine |
| US20140196697A1 (en) * | 2013-01-15 | 2014-07-17 | Southwest Research Institute | Internal Combustion Engine Having Dedicated EGR Cylinder(s) With Intake Separate From Intake Of Main Cylinders |
| US8931256B2 (en) | 2013-01-31 | 2015-01-13 | Electro-Motive Diesel, Inc. | Engine system with passive regeneration of a filter in EGR loop |
| US9021785B2 (en) | 2013-01-31 | 2015-05-05 | Electro-Motive Diesel, Inc. | Engine system for increasing available turbocharger energy |
| US9163586B2 (en) | 2013-01-31 | 2015-10-20 | Electro-Motive Diesel, Inc. | Exhaust system having parallel EGR coolers |
| US9255552B2 (en) | 2013-05-08 | 2016-02-09 | Electro-Motive Diesel, Inc. | Engine system having dedicated donor cylinders for EGR |
| US9347367B2 (en) | 2013-07-10 | 2016-05-24 | Electro-Motive Diesel, Inc. | System having dual-volute axial turbine turbocharger |
| US9644528B2 (en) | 2013-01-31 | 2017-05-09 | Electro-Motive Diesel, Inc. | Engine system with EGR over-pressure protection |
-
1981
- 1981-02-19 GB GB8105242A patent/GB2093909A/en not_active Withdrawn
Cited By (29)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1988002065A1 (en) * | 1986-09-13 | 1988-03-24 | Mtu Motoren- Und Turbinen-Union Friedrichshafen Gm | Multi-cylinder diesel internal combustion engine with low compression ratio in the cylinders |
| US4860716A (en) * | 1986-09-13 | 1989-08-29 | Mtu-Motoren Und Turbinen Union | Multi-cylinder diesel internal combustion engine with low compression ratio in the cylinders |
| WO2001044650A1 (en) * | 1999-12-17 | 2001-06-21 | Mtu Friedrichshafen Gmbh | Exhaust gas recirculation device |
| GB2371087A (en) * | 2000-11-20 | 2002-07-17 | Ford Global Tech Inc | A supercharged engine where cylinders in non-firing mode provide compressed air to the firing cylinders |
| GB2371087B (en) * | 2000-11-20 | 2004-10-06 | Ford Global Tech Inc | A supercharged engine |
| WO2006032886A2 (en) * | 2004-09-21 | 2006-03-30 | Lotus Cars Limited | A combustion chamber deactivation system |
| US7962276B2 (en) | 2004-09-21 | 2011-06-14 | Lotus Cars Limited | Combustion chamber deactivation system |
| WO2006032886A3 (en) * | 2004-09-21 | 2006-05-18 | Lotus Car | A combustion chamber deactivation system |
| GB2418228B (en) * | 2004-09-21 | 2006-11-22 | Lotus Car | A multiple combustion chamber internal combustion engine with a combustion chamber deactivation system |
| JP2008513683A (en) * | 2004-09-21 | 2008-05-01 | ロータス カーズ リミテッド | Combustion chamber operation stop system |
| EP1992809A2 (en) * | 2004-09-21 | 2008-11-19 | Lotus Cars Limited | A multiple combustion chamber internal combustion engine with a combustion chamber deactivation system |
| EP1992809A3 (en) * | 2004-09-21 | 2009-01-07 | Lotus Cars Limited | A multiple combustion chamber internal combustion engine with a combustion chamber deactivation system |
| JP4808719B2 (en) * | 2004-09-21 | 2011-11-02 | ロータス カーズ リミテッド | Combustion chamber operation stop system |
| GB2418228A (en) * | 2004-09-21 | 2006-03-22 | Lotus Car | Multiple combustion chamber internal combustion engine with a combustion chamber deactivation system |
| FR2885177A1 (en) * | 2005-04-27 | 2006-11-03 | Renault Sas | Internal combustion engine e.g. diesel engine, has air intake circuit allowing air into combustion cylinders, where part of air flow is aspirated by recirculation cylinder via conduit placed downstream of recirculation cylinder |
| US7779823B2 (en) | 2007-07-12 | 2010-08-24 | Ford Global Technologies, Llc | Cylinder charge temperature control for an internal combustion engine |
| US7801664B2 (en) | 2007-07-12 | 2010-09-21 | Ford Global Technologies, Llc | Cylinder charge temperature control for an internal combustion engine |
| US8020525B2 (en) | 2007-07-12 | 2011-09-20 | Ford Global Technologies, Llc | Cylinder charge temperature control for an internal combustion engine |
| US7765994B2 (en) | 2007-07-12 | 2010-08-03 | Ford Global Technologies, Llc | Cylinder charge temperature control for an internal combustion engine |
| US8074629B2 (en) | 2007-07-12 | 2011-12-13 | Ford Global Technologies, Llc | Cylinder charge temperature control for an internal combustion engine |
| US8205583B2 (en) | 2007-07-12 | 2012-06-26 | Ford Global Technologies, Llc | Cylinder charge temperature control for an internal combustion engine |
| US9206769B2 (en) * | 2013-01-15 | 2015-12-08 | Southwest Research Institute | Internal combustion engine having dedicated EGR cylinder(s) with intake separate from intake of main cylinders |
| US20140196697A1 (en) * | 2013-01-15 | 2014-07-17 | Southwest Research Institute | Internal Combustion Engine Having Dedicated EGR Cylinder(s) With Intake Separate From Intake Of Main Cylinders |
| US8931256B2 (en) | 2013-01-31 | 2015-01-13 | Electro-Motive Diesel, Inc. | Engine system with passive regeneration of a filter in EGR loop |
| US9021785B2 (en) | 2013-01-31 | 2015-05-05 | Electro-Motive Diesel, Inc. | Engine system for increasing available turbocharger energy |
| US9163586B2 (en) | 2013-01-31 | 2015-10-20 | Electro-Motive Diesel, Inc. | Exhaust system having parallel EGR coolers |
| US9644528B2 (en) | 2013-01-31 | 2017-05-09 | Electro-Motive Diesel, Inc. | Engine system with EGR over-pressure protection |
| US9255552B2 (en) | 2013-05-08 | 2016-02-09 | Electro-Motive Diesel, Inc. | Engine system having dedicated donor cylinders for EGR |
| US9347367B2 (en) | 2013-07-10 | 2016-05-24 | Electro-Motive Diesel, Inc. | System having dual-volute axial turbine turbocharger |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |