AU763652B2

AU763652B2 - Variable displacement diesel engine

Info

Publication number: AU763652B2
Application number: AU67730/98A
Authority: AU
Inventors: Henry W. Cummings
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-03-26
Filing date: 1998-03-26
Publication date: 2003-07-31
Anticipated expiration: 2018-03-26
Also published as: AU6773098A; JP2002507690A; CA2324404A1; EP1066457A4; EP1066457A1

Description

WO 99/49193 PCT/US98/05832 VARIABLE DISPLACEMENT DIESEL ENGINE I FIELD OF THE INVENTION This invention relates to internal combustion engines in general, and in particular to diesel engines for industrial applications such as heating, air conditioning, manufacturing equipment, electricity, marine, and automotive.

This application is a continuation of US S.N. 08/706,998 filed 9/4/96.

II BACKGROUND OF THE INVENTION The Diesel engine, invented and perfected by Rudolfph Diesel in the 1890s, is used extensively for a wide variety of applications, including ships, overland trucks, heating and air conditioning, and-automotive. The size of the engine varies widely depending on the load.

In 1981 the Cadillac Division of General Motors marketed a variable displacement gasoline engine for automotive use.

The -6.0 liter enine would sbwit from eight to four or six cylinders depending on the load perceived by a computer.

When the engine operated in the four or six cylinder mode, fuel was not introduced into the remaining cylinders, so that a saving in fuel was achieved when the engine was operated in the four or six cylinder mode, as compared to fuel consumption in the eight cylinder mode. However, the eight cylinder mode provided the advantage of a powerful full 6.0 liter displacement engine when driving conditions required significant power, such as steep hills, or rapid accelaration. Both full size rear wheel seven passenger, stretch limozines, and smaller front wheel drive models utlilized the 4-6-8 engine.

-1- WO 99/49193 DPT/U f0l 12O3% W O l99/4 93U 70/UJOJ However, the concept was not offered after 1981, and there were class action law suits alleging that the concept was technically unsound, and/or had not been sufficiently developed to be introduced into the auto market commercially.

However, the Inventor's 1981 4-6-8 works fine.

Many Diesel engines must operate on widely varying load conditions. For example, a Dieset locomotive and a Diesel overland truck experience much greater loads going up hill in the Rocky Mountains than going down such mounatains, or over flat farmland of much of the midwest.

Marine Diesels require much less power going down river than up river.

Industrial Diesel engines that provide power for air conditioning and/or heating systems experience lower loads in evenings and on weekends, when only a fraction of full power is required.

Many other examples of the load variations Diesel engines experience will be apparent to those skilled in Diesel engine art.

As described in Motor Trend, May 1993 v45 n5 p 7 8, the 1993 Honda VTEC engine utilizes a variable displacement system which acts on all six cylinders which utilizes a hydraulic system for controlling the valves in this variable displacement system.

-2- WO 99/49193 PCT/US98/05832 III SUMMARY OF THE INVENTION A. OBJECTS OF THE INVENTION One object of the present invention is to reduce the operating cost of diesel engines when operating on light and intermediate load conditions.

Another object is to reduce maintenance costs by varying the cylinders used under low and intermediate load conditions.

Another object is to have availablehigh power when unexpected heavy load conditions arise.

Other objects will be apparent from the following SUMMARY, DESCRIPTION OF PREFERRED EMBODIMETS'c, DRAWINGS and CLAIMS.

B. SUMMARY In accordance with the present invention the variable displacement concept of the 1981 automobile gasoline engine is utilized to reduce Diesel fuel costs when the Diesel engines are operating on light and intermediate loads.

Keeping Diesel engines running on all cylinders, on light or intermediate load, for many automotive, locomotive, marine and industrial applications is fuel inefficient, causes unnecessary wear of engine parts, and/or is expensive.

In accordance with the invention, +ke number of operative cylinders of Diesel engines is reduced under low load, and/or intermediate load operating conditions by not providing fuel to selected cylinders, under light and/or intermediate load conditions, and then under heavy load conditions, more cylinders, or all cylinders are activated and provided with fuel for combustion.

WO 99/49193 PCTIUS98/05832 In accordance with another embodiment of the present invention, prior to restoring fuel to inactive cylinders if the inactive cylinders have become below minimum operating temperature, the respective glow plugs of the previously inactive cylinders are Artivated to heat up the cylinders prior to re-introducing fuel.

In accordance with another embodiment of the invention the shut down of selected cylinders under light load and reactivation under heavy load is computer controlled including control of reactivation of the respective glow plugs prior to reintroduction of fuel into the previously deactivated cylinders to insure that the previously inactive cylinders are sufficiently warm for the combustion process.

In accordance with another embodiment of the invention, the computer controls selection of cyt 4 "ders to be operated at low and intermediate load, to alternate and/or switch operative cylinders, so that cylinder, piston, plug, valve and other parts wear is generally even, whereby cylinder repair is reduced and maintenance cost is reduced.

In accordance with another embodiment of the present invention, the computer controls cylinder selection during low and intermediate load conditions to select cylinders to be operated whereby the temperature of the inactive -4- WO 99/49193 PCT/US98/05832

L

cylinders is prevented from becoming sufficiently coolfto cause significant stress between cylinders due to contraction and/or expansion of cylinder, piston, plug or other parts in the engine.

In accordance with another embodiment of the invention, in applications where it is not possible to vary the specific cylinders to not be given fuel, the computer reactivates some additional, or all additional cylinders if the temperature of one or more inactive cylinders, or other parts of the engine become sufficiently cool to cause significant stress between cylinders or between other engine parts due to contraction and/or expansion of engine parts.

THE DRAWINGS Figure 1 is a schematic perspecive view of one embodiment of a "V" lype Diesel engine of the present invenion.

Figure 2 is a schematic perspective view illustrating the valve assemblies which may be used in he present invention.

Figure 3A is a schamatic perspective view of the valve selector assembly with the cylinder in operative posiion.

Figure 3B is a schamatic perspecive view of the valve selector assembly in the blocking position with the cylinder in inoperative.

Figure 4 is a schematic side elevaion view of a cam shaft, cam, push rod, rocker arm and valve which may be used in the present invention.

Figure 5 is a schematic perspective view of an in-line Diesel engine which may be utilized in the present invention.

WO 99/49193 PCT/US98/05832 Figure 6 is a schematic illustration of a Computer Controlled Variable Displacement Diesel engine with cylinders, glow plugs and cylinder temperature sensors for each cylinder being controlled by the computer.

Figure 7 is a schematic illustration of a Flow chart of the computer control utilized in the present invention including computer controlled glow plug and cylinder activation and deactivation sequence of the present invention.

Figure 8 is a flow chart of a computer controlled glow plug and cylinder activation sequence for individual cylinders.

Figure 9 is an illustration of an automobile powered by the variable displacement Diesel engine of the invention.

Figure 10A is a vertical schematic illustration of an office building which is heated and cooled by the Variable Displacement Diesel Engine of the invention.

Figure 10 is a view looking in the direction of the arrows along the line 10-10 in Figure Figure 10B is an illustration of an overland truck powered by the variable displacement Diesel engine of the invention.

Figure 11 is an illustration of a railway locomotive powered by the variable displacement Diesel engine of the invention.

Figure 12 is an illustration of a marine tug boat powered by the variable displacement Diesel engine of the invention.

-5/1 DESCRIPTION OF PREFERRED EMBODIMENTS In accordance with one embodiment of the present invention, an automotive diesel engine is provided with means for deactivating one or more cylinders during low load and/or moderate load conditions, and with means for re-activating some or all of the deactivated cylinders under greater or full load.

In accordance with the invention, the number of operative cylinders of an automotive Diesel engine for example, but not limited to a Diesel engine similar to, a General Motors 5.7 liter V-8 Diesel engine is reduced under low load, and/or intermediate load operating conditions by not providing Diesel fuel to selected cylinders, under light and/or intermediate load conditions, and then under heavy load conditions, more cylinders, or all cylinders are activated and provided with fuel for combustion.

In accordance with another embodiment of the present invention, prior to restoring fuel to inactive cylinders if the inactive cylinders have become below minimum operating temperature as determined by a temperature sensor, the computer S: activates the respective glow plugs of the previously inactive cylinders to heat up the cylinders prior to re-introducing fuel.

As an example, when the engine is subject to low load, such as cruising in relatively flat highway or going down hill, two or four cylinders may be deactivated, preferably four.

If four cylinders are deactivated under moderate load such as encountering a hill with a small incline, then two additional cylinders are activated by the computer as the hill is *oo* encountered.

0. The shut down of selected cylinders under light load and •go* reactivation under moderate and/or heavy load is computer controlled including control of reactivation of the respective glow plugs prior to reintroduction of fuel into the previously deactivated cylinders to insure that the previously inactive cylinders are sufficiently warm for the combustion process.

-6- In accordance with another embodiment of the present invention, means are provided for maintaining closed during deactivation one or both of the inlet and exhaust valves of each cylinder which is deactivated.

In accordance with another embodiment of the invention, the computer controls selection of cylinders to be operated at low and intermediate load, to alternate and/or switch operative cylinders, so that cylinder, piston, plug, valve and other parts wear is generally even, whereby cylinder repair is reduced and maintenance cost is reduced. In accordance with another embodiment of the present invention, the computer controls cylinder selection during low and intermediate load conditions to select cylinders to be operated whereby the temperature of the inactive cylinders is prevented from becoming sufficiently cool to cause significant stress between cylinders due to contraction and/or expansion of cylinder, piston, plug or other parts in the engine.

In one specific embodiment of the invention, a General Motors eight cylinder, 5.7 liter Diesel engine is provided with S means to deactivate two or four cylinders during periods of light or moderate engine load. As an example, the means to deactivate S the cylinders may comprise generally a Modulated Displacement system utilized in the 1981 Cadillac 6.0 liter 4-6-8 gasoline engine, modified to the extent necessary, or desirable to adapt to and computer control the 5.7 liter General Motors Diesel engine.

Information about the two engines, the Modulated System, and the Computer System are publicly available, for example in the 1981 Cadillac Service Information Manual, including Appended Electrical and Mechanical Wiring Diagrams, available from General Motors, Cadillac Motor Division, Detroit Michigan 48232; many Public Libraries, and Haynes Publishing Company, hereby incorporated into the present application by this reference.

The engines are similar in size as to block, bore, stroke and displacement, with the Diesel displacement slightly smaller.

However, because of the similar engine size, the Modulated Displacement principles and computer control utilized in liter V-8 may be utilized in the General Motors 5.7 liter Diesel engine to deactivate four and/or two cylinders with relatively small modifications.

In a preferred embodiment temperature sensors are provided in at least the cylinders to be deactivated, and preferably in all cylinders to monitor the temperature of the deactivated cylinders, and preferably the temperature of the cylinders which remain active.

If the computer senses that the temperature of deactivated S: cylinders has become lower than the temperature necessary for spontaneous combustion, in one embodiment, the glow plug for that or those cylinders are turned on to enable spontaneous combustion if load conditions change, such as encountering a hill, or a need to accelerate. After proper operating temperature is reached, if the load does not change, the glow plugs are turned off until the temperature again drops below operating temperature range, or an increased load occurs, and the cylinders are again activated.

In accordance with another embodiment of the invention, S after the computer turns on the glow plug or plugs of cylinders deactivated, such cylinders are reactivated until the cylinder temperature again reaches a desired operating temperature, even if the load condition does not increase.

In accordance with another embodiment, temperature sensors for each cylinder are not provided, and the computer senses lowering of temperature in the cooling fluid, and activates glow plugs of deactivated cylinders after a pre-determined temperature drop and optionally reactivates such deactivated cylinders even if load conditions do not increase.

While the later embodiment, which does not require adding additional sensors is less expensive, it does not provide for as accurate control of cylinder temperature and optimum conditions for spontaneous combustion of previously deactivated cylinders.

As described on pages 6A-37A of the 1981 Cadillac Information Manual the MD system senses Engine Revolutions per minute, Coolant Temperature, Throttle Position, and Absolute Pressure in the Intake Manifold.

In accordance with one or more previous embodiments the MD system is modified to sense and process in a computer engine control system other variables including, but not limited to, individual cylinder temperature, and the pressure or absence of the operation of the glow plugs for given cylinders. Information obtained from sensors is sent to a suitable electronic computer processing unit (ECP) containing one or more computer programs to assimilate and process the data obtained from the sensors. The ECP processes the data and determines the number of operating cylinders required for the given load condition.

In accordance with one embodiment, four valve selectors are utilized to deactivate either four or two cylinders to enable the engine to operate on either four or six cylinders, after start up on eight cylinders, and operation on eight cylinders on heavy load conditions.

In another embodiment four valve selectors are used to deactivate four cylinders, and operation of four cylinders occurs S on low or moderate load conditions, and eight cylinder operation occurs on start up and heavy load conditions. While this embodiment causes somewhat more operation on eight cylinders, and a small increase in fuel consumption, under both four and eight cylinder operation, the engine loads are relatively balanced and engine vibration is reduced as compared to 4-6-8 operation when some engine vibration occurs in the six cylinder operation mode.

In one embodiment, valve selectors are installed on cylinders 1, 4, 6 and 7. In the four cylinder mode, cylinders 1, 4, 6 and 7 are deactivated. In the six cylinder mode, only cylinders 1 and 4 are deactivated.

In accordance with another embodiment of the present invention, the valve system utilized in the General Motors 4-6-8 gasoline engine is utilized to control the active cylinders in a 5.7 liter diesel engine illustrated in Figures 1 and 2.

In Figs. 1 and 2, a 5.7 liter diesel engine 10 is shown including a lower block 12 having cylinders therein 14 to receive pistons (not shown). Block 12 receives a head 16, a gasket 17, inlet valves 18 and exhaust valves 19. Inlet valves 18 and exhaust valves 19 are controlled by a rocker arm assembly including push rods 22, rocker arms 24, a rocker arm pivot 26, a pedestal 28, and springs 29. Temperature sensors are shown at Figure 4 is a view illustrating a cam shaft 42, having a cam 8a. 44, with a cam lobe 46 which causes movement in the push rod o o which causes pivotal movement of the rocker arm 24 and opening and closing of the valve 18.

Specifically, as shown in Figs. 3A 3B, valve selector .0*0 a 0.0 assemblies 30 are mounted on the intake and exhaust rocker arms 24 above the rocker arm fulcrum point 26. The valve selector assemblies 30 include a solenoid valve 34 which activates a piston 36 which is connected to a blocking plate 38.

During conventional active operation Figure 3A, the rocker o00.

arm 24 pivots near the center fulcrum point 26, of the rocker oY arm. As the operative cam 42 reaches its highest point 46, Figure •coo 4, the valve 18 is open allowing the fuel and air mixture to 0eo0 enter cylinders 14.

oo As shown in Figures 3B, when the solenoid valve 34 is activated, and the piston 36 is moved from the position shown in Figure 3A left to right to the position illustrated in Figure 3B, wherein the blocking plate 38 has been moved from the position shown in Figure 3A to the position shown in Figure 3B. In this position the pivot point has been moved to the position shown in Figure 3B at 32, whereby when the cam is again at its high point the valves will not open because the rocker arm does not pivot at the center point 26, but rather at the pivot point 32. This allows the rocker arm to slide up and down on its mounting stud The valve selector operation is not limited to a V8 engine and may be utilized generally from example in Diesel V6 engine.

Furthermore, the cam shaft for the Diesel engine may be located above the valves and a valve selector operation utilized as described in detail in U.S Patents 4,546,734 and 4,615,307, hereby incorporated into the present application by this reference.

Moreover, the Diesel engine may be an overland truck engine, a train locomotive engine, a marine Diesel engine for ships and/or barges, or a Diesel engine for industrial power plant applications, including, but not limited to heating and air .98 conditioning of office buildings or plants.

oo For many applications the computer is programmed not to activate the valve selector operation until a high or overdrive gear is reached by the transmission. For heavy load applications .ego all cylinders should be activated in low gears.

The number of cylinders to be deactivated will vary with the type of engine. For example. Six cylinder in line-overland truck engines may deactivate either three or preferably two cylinders at light load. V-8, V-12, and V-16 engines will be programmed to deactivate more cylinders in light or even moderate load applications. Proper computer programming and control is necessary to achieve successful operation.

The particular valve selector arrangement will also vary with the application. For appropriately sized V type engines, selectors of the type used by General Motors in the 4-6-8 gasoline engine may be used. For other applications dimensions -11and load carrying members in the selector assemblies may be modified to meet particular applications. Moreover the particular valve selector design will depend upon dimensions of the engine, loads to be encountered, and projected life before overhaul.

As an example, the Cummins Mil (brochure hereby incorporated into this application by this reference) is a computer controlled six cylinder engine which may be readily provided with valve selectors, and the computer programs modified to achieve valve selector operation, and even greater fuel economy, and perhaps less wear and longer life between overhauls.

Figure 5 illustrates an in-line six cylinder M11 computer controlled Cummins Diesel engine 50 including a high strength cylinder block 52 having cylinders 54 receiving pistons 60. The pistons 60 are connected to connecting rods 64 which are in turn connected to a hardened crank shaft 66. A gear train 68 drives a cam shaft having lobes 72 which control movement of push rods 74 which pivot rocker arms 76 to move valve stem 78 and open and close valves Two or more valve selectors 82 constructed in the same manner as valve selector 30 including solenoid valve 84, having a piston and a blocking plate 88, appropriately dimensioned for the Mll engine are then installed to deactivate two or three cylinders under low or moderate load conditions when the transmission is in high and/or overdrive gear under the control of the CELECT Plus computer 90 whose program 92 is modified to include a deactivation-activation program 94 to control deactivation and activation of selected cylinders 54, and control a.

S operation of the glow plugs.

Alternatively the valve selector operation described in U.S S Patents 4,546,734 and/or 4,516,307 may be utilized under the a control of computer 90 and a deactivation-activation program 94.

Figure 6 illustrates a computer 7 controlling cylinders 1,2,3 in an N Cylinder diesel engine with the sensors 15,25,35, glow plugs lGP 2GP, and 3GP, injectors 11,21,31, intake valves lVi,2Vi,3Vi, exhaust valves lVe,2Ve,3Ve, and valve -12actuators/deactivators lVa,2Va,3Va, for all cylinders. The computer 7 receives the cylinder temperatures from Sensors 15,25,35, the Load L from a load sensor Ls, data from other sensors Sx,Sy,etc. and computes which cylinders should be deactivated and activated, when the glow plugs of various cylinders are to activate prior to activating cylinders, and sends electrical signals to the Valve Actuator/Deactivators lVa,2Va,3Va, Glow Plugs 1GP,2GP,3GP, and fuel injectors 11,21,31 to activate and deactivate various cylinders, depending on the load, the temperature of the individual cylinders, and other commonly computer controlled variables.

The computer as an example may be the Electronic Diesel Control (EDC) processing init described in DIESEL FUEL INJECTIONS, Bosh, 1994 EREF TJ 797 D55,pp 186-191, hereby incorporated into the present application by this reference.

The control of the various cylinders in monitored and controlled in a manner illustrated in Figures 7 and 8. Figures 7 and 8 illustrate a Summary of the Computer Glow Plug and Cylinder Activation Sequence used by the computer in controlling activation and deactivation of cylinders and glow plugs during operation. A sample Computer Program is found in the Application Appendix in Pseudo code.

The program 500 includes a first step 502 of turning on the engine which is activated by the ignition key and includes the Step of activating the program 600 in Figure 8 which activates the glow-plugs for all cylinders and heating up all cylinders prior to ignition. At Step 504 when minimum operating temperature S is reached in each cylinder the starter motor for the engine is turned on at Step 506.

.o At step 508 the program obtains the temperature and loads for all cylinders. In some embodiments it may be activated by S reaching a selected transmission gear such as after the engine reaches high gear for an automotive embodiment.

-13- At Step 510, if any cylinders are below a minimum operating temperature the cylinder flags for operating the glow plugs in the program 600 in Figure 8 are activated.

At Step 512 the program determines whether the load L is less than a selected load Ll.If the load is less than L1 at Step 514 this program calls the program 600 to activate glow plugs to warm up any cold cylinders.

At Step 516 cylinders are deactivated and remain deactivated until the load exceeds L1.

If the answer to the load evaluation Step 512 is negative at Step 518, the Program determines if the load is less than a larger load L2. If the answer is affirmation at Step 520, cylinders are deactivated which are not needed for medium loading. After cylinders have been deactivated at 520, Step 522 calls program 600 to warm up any cold cylinders. If the answer to the question at Step 518 is negative, in Step 524 it is determined whether or not 6 cylinders are running with the start cylinder program 600.

At step 526, the program asks if the load is greater than D. load L3. If the answer is affirmative, then additional cylinders are turned on with the program at 600.

It is to be noted that if the load is less than L1 at Step 512 and, for example, only 4 cylinders are operated, nonetheless eeoc at 514 the program calls the start cylinder program 600 to be certain that all cylinders are at a minimum operating temperature and, if they are not, they are warmed up in accordance with program 600. The same applies to a situation where the load is S less than L2, but a time period has elapsed and it is necessary to check at Step 520 to make sure that deactivated cylinders are .30 nonetheless at a minimum temperature to avoid thermal stress of the engine.

.In program 600 in the first step, 602, the program orders that the temperature for a given cylinder be read at 604.At step 606 if the temperature of the cylinder is less than a predetermined temperature T1 then at Step 608 the glow plug for -14that cylinder is activated. If the answer to the question at Step 606 is in the affirmative, the cylinder is activated at Step 610.

At step 612 if the cylinder temperatures was initially below T1 so that the glow plug was activated at step 608, at step 612 the cylinder will be required to operate for at least 10 minutes to warm-up the cylinder to avoid thermal stress in the engine.

After these steps are taken this Program for a given cylinder is deactivated at Step 614, and the same Steps are taken for another cylinder, until all cylinders are so processed. Thus the program 600 operates continuously for each of the cylinders in the engine.

Figure 9 illustrates an automobile embodiment 120 in which an automobile 122 is powered by a Variable Displacement Diesel Engine of the present invention 124 having electrical wires 126 connecting the engine cylinders 127 to a computer 128 for controlling the operation, activation and deactivation of the cylinders in accordance with the present invention.

Figures 10 and 10A illustrate a building 100 having floors 102 which may be used for manufacturing and/or office work such ."2Q as administration. The building 100 including floors 102 is heated and cooled during the seasons of the year by a variable

S.

displacement Diesel engine 104 constructed and operated according to the principles of the present invention which drives a load comprising a heating and air conditioning unit 106 by means of shaft 108.

During evenings, weekends, and holidays the load experienced by unit 106 may be significantly reduced, allowing deactivation of cylinders in the Diesel engine 104 in accordance with the present invention by computer 109.

o@ 0 Figure 10B illustrates an overland truck embodiment in which O o an overland truck 130 having a trailer 132 is powered by a o oo Variable Displacement Diesel Engine of the present invention 134 having electrical wires 136 connecting the engine cylinders 137 to a computer 138 for controlling the operation, activation and deactivation of the cylinders in accordance with the present invention.

Figure 11 illustrates a train-locomotive embodiment in which a train 140 having a locomotive 142a and cars 142b, 142c, 142n, is powered by a Variable Displacement Diesel Engine of the present invention 144 having electrical wires 146 connecting the engine cylinders 147 to a computer 148 for controlling the operation, activation and deactivation of the cylinders in accordance with the present invention.

Figure 12 illustrates a marine embodiment in which a tug boat 150 having a cargo deck 152 is powered by a Variable Displacement Diesel Engine of the present invention 154 having electrical wires 156 connecting the engine cylinders 157 to a computer 158 for controlling the operation, activation and deactivation of the cylinders in accordance with the present invention.

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*55 Soo* 06o o 0°ooo giv0 -16- WO 99/49193 PTU9/53 PCTIUS98/05832

APPENDIX

COMPUTER PROGRAM void StartCvlinder(irn Cylinder) mnt T1=MfinTemp; Tempf Cylinder] GetTexnp(Cylindcr) if( Tempf Cylinder] T I) Cylinder is warm so start it ActivateCvlinder(Cyline)., if( Cold[Cylinder) WarmnTimefCylinderl 10.0; ColdICylinderl

FALSE;

else Cylinder is cold so warm it StartGlowPlug(Cyljnder); void running() float Li LowloadValue; float L2 MedLoad Value; float L3 HighLoadValue, Initialize warmtime and cold cylinder flags for( Cold[i] =FALSE; WarmTime 0.0; Continue looping while engine is running while( running) Obtain current load from sensor Sq L Get-oado; Obtain current temperatures of each cylinder and identify cold cylinders*/ for( i= I Templil GetTemp(i); if( Temp[i] T2) Coldf ii TRUE; elseif(Templil T3) if(WarmTimelil 0.0 WarmTimetl WarmnTiine[iJ DeltaTime; if(L Li) Deactivate 4 cylinders unider light loading for(i1l;i<9;i++)( if( cold[iJ 1* Warm up all cold cylinders StartCylinder(i); elseif( i>4)f Deactivate 4 cylinders under light loading if not being warmed up if( WarnTimij DeactivateCylinder(i); 24- 17 WO 99/49193 WO 9949193PCTIUS98/05832 elseif (L forQi=l;i<9;i++){ if( cold[il Warm up all cold cylin.rders loading StartCylinder(i); elseif( i>6) Deactivate 2 cylinders under medium loading if not being warmed up if( WarmTime[i] DeactivateCvlinder(i); else( 1. Greater than medium loading make sure 5&6 are running StartCylinder(6); if( L L3 Heavy loading -start 7and 8* StartCylinder(7); StartCylinder(8);

Claims

1. A method of operating a variable displacement Diesel engine including: providing a Diesel engine having a plurality of cylinders with pistons moveable within said cylinders; said pistons connected to a crank shaft; said cylinders at least partially defining combustion chambers in said engine; supplying Diesel fuel to said combustion chambers; operating valve means for introducing air and fuel for combustion into said combustion chambers, and for allowing combustion gasses to exit from said combustion chamber; applying a load to said crank shaft; under computer control reducing the number of operative cylinders under reduced load operating conditions including discontinuing the supply of fuel to selected cylinders; under increased load conditions, computer controlled activating additional cylinders, including providing said deactivated cylinders with fuel for combustion. S

2. A method of operating a variable displacement Diesel engine including: providing a Diesel engine having a plurality of cylinders with pistons movable within said cylinders; said pistons connected to a crank shaft; said cylinders at least partially defining combustion chambers in said engine; supplying Diesel fuel to said combustion chambers; activating glow plugs for heating said combustion chambers to minimum operating temperature; operating valve means for introducing air and fuel "2 for combustion into said combustion chambers, and for allowing combustion gasses to exit from said combustion chamber; applying a load to said crank shaft; under computer control reducing the number of operative cylinders under reduced load operating conditions including discontinuing the supply of fuel to selected cylinders; under increased load conditions, computer controlled activating additional cylinders, including providing said deactivated cylinders with fuel for combustion; and computer -19- controlled activating the respective glow plugs of the previously inactive cylinders if the temperature of said inactive cylinders has become below a minimum operating temperature, to heat up the deactivated cylinders and then re-introducing fuel into said deactivated cylinders.

A method of operating a variable displacement Diesel engine according to claim 2 including controlling the shut down of selected cylinders under light and/or intermediate load and reactivation under heavy load by computer and computer controlling reactivation of the respective glow plugs prior to reintroduction of fuel into the previously deactivated cylinders.

4. A method of operating a variable displacement Diesel engine according to claim 1 or 2 including controlling by computer selection of cylinders to be operated at low and intermediate load, and selection of cylinders to alternate and switch.

5. A method according to claim 4 wherein the Diesel engine S powers an automobile.

6. A method according to claim 4 wherein the Diesel engine powers an overland truck.

7. A method according to claim 4 wherein the Diesel engine :26 powers a railway locomotive.

8. A method according to claim 4 wherein the Diesel engine powers a marine vehicle.

9. A method according to claim 4 wherein the Diesel engine powers an industrial plant.

10. A method according to claim 4 wherein the Diesel engine powers heat and air conditioning equipment.

11. A method of operating a variable displacement Diesel engine according to claim 4 including sensing the temperature of the cylinders and computer controlling cylinder selection during reduced load conditions to select cylinders to be operated whereby the temperature of inactive cylinders in prevented from becoming sufficiently cool to cause excessive stress between cylinders. JUN.16'2003 11:11 61732210661 AER O 37 .0 AHEARN FOX #3776 P.004

12. A method of operating a variable displacement Diesel engine according to claim 4 including sensing the temperature of cylinders and other parts of the engine; reactivating by computer additional cylinders if the temperature of at least one. inactive cylinder, or other parts of the engine become sufficiently cool to cause excessive -stress between cylinders or between engine parts due to contraction and/or expansion of engine parts.

13. A variable displacement Diesel engine including an engine block having a plurality of cylinders with pistons movable within said cylinders; said pistons connected to a crank shaft; said cylinders at least partially defining combustion chambers in said engine; means for supplying Diesel fuel to said combustion dtaii~ber; valv6 means for iftkddfftcizg 'air and fuel f~bIW into said combustion chamber and for allowing combustion gasses to exit from said combustion chamber; means for applying a variable load to said crank shaft; characterized by the provision of computer controlled means for reducing the number of operative cylinders under reduced load R~tj^na -n#Iif49 lv4 I- IU. ULfr.L) of fuel to selected cylinders under reduced load conditions; and under increased load conditions computer controlled means for activating additional cylinders including means for supplying deactivated cylinders with fuel for combustion.

14. A variable displacement Diesel engine including an engine block having a plurality of cylinders with pistons movable within said cylinders; said pistons connected to a crank shaft; said cylinders at least partially defining combustion chambers in said engine; means for supplying Diesel fuel to said combustion chamber; glow plugs for heating said combustion chambers to minimum operating temperature; valve means for introducing air W and fuel for combustion into said combustion chamber and for allowing combustion gasses to exit from said combustion chamber; means for applying a variable load to said crank shaft; characterized by the provision of computer controlled means for -21- 16/06 '03 MON 11:05 [TX/RX NO 94421 JUN.16'2003 11:12 61732210661AHPNFO#36P.0 AHEARN FOX #3776 P.005 reducing the number of operative cylinders under reduced load operating conditions including means for discontinuing the supply of fuel to selected cylinders under reduced load conditions; and under increased load conditions computer controlled means for activating additional cylinders including means for supplying- deactivated cylinders with fuel for combustion, and computer controlled means for activating the respective glow plugs of the previously inactive cylinders if the previously inactive cylinders have become below a minimum operating temperature, to heat up the deactivated cylinders and then re-introducing fuel to said deactivated cylinders.

A variable displacement engine according to claim 13 or 14 wherein the computer controls selection of cylinders to be operated at low and intermediate load, to alternate and switch operative cylinders.-

16. A variable displacement Diesel engine according to claim including temperature sensor means connected to said computer and wherein the computer controls cylinder selection during reduced temperature of inactive cylinders is prevented from becoming sufficiently cool to cause significant stress between cylinders.

17. -A variable displacement Diesel engine according to claim 16 including temperature sensing means connected to said computer and wherein the computer reactivates additional cylinders if the temperature of one or more inactive cylinders, or other parts of the engine become sufficiently cool to cause significant stress between cylinders or between engine parts due to contraction or expansion of engine parts.

18. A variable displacement Diesel engine according to claim 16 wherein temperature sensing means are provided in the engine o which are read by said computer to control activation and deactivation of cylinders.

19. A variable displacement Diesel engine according to claim 18 wherein the Diesel engine is provided with a cooling system for -22- 16/06 '03 MON 11:05 [TX/RX NO 9442] JtN.16'2003 11:12 61732210661 AER O 37 .0 AHEARN FOX #3776 P.006 cooling the cylinders in the engine and a f luid exit Conduit is connected to the last cylinder cooled by the system and wherein temperature sensing means are provided in the coolant fluid exit conduit after the last cooled cylinder of the engine.

A variable displacement Diesel engine according to claim 19 wherein the Diesel engine is provided with a cooling systemr for cooling the cylinders in the engine and a fluid entrance conduit is connected to the first cylinder cooled by the system and wherein temperature sensing means are provided in the coolant fluid entrance conduit before the first cooled cylinder of the engine,

21. A variable displacement Diesel engine according to claim is wherein temperature sensing means are provided in the cylinder wall of each cylinder in the engine.

22. A variable displacement Diesel engine according to claim 18 wherein temperature sensing means are provided in each cylinder in the engine adjacent the combustion chamber for that cylinder.

23. A variable displacement Diesel engine according to claim 13 or 14a Whpe04 m i-~j qa~j-. ae -typ Dvm eacl engine

24. A variable displacement Diesel engine according to claim 23 wherein the Diesel engine is an automotive Diesel engine.

A variable displacement Diesel engine according to claim 24 wherein the Diesel engine is a 5.7 liter V-B Diesel engine.

26. A variable displacement Diesel engine according to claim 13 or 14 wherein the Diesel engine is an in-line type Diesel engine.

27. A variable displacement Diesel engine according to claim 13 or 14 wherein said Diesel engine powers and overland truck engine.

28. A variable displacement Diesel engine according to claim 13 or 14 wherein said Diesel engine powers a railway locomotive Q engine.

29. A variable displacement Diesel engine according to claim 13 or 14 wherein said Diesel engine powers a marine Diesel engine.

A variable displacement Diesel engine according to claim 13 16/06 '03 MON 11:05 [TX/RX NO 9442] JUN.16'2003 11:12 61732210661 AH{EARN FOX #3776 P.007 or 14 wherein said Diesel engine powers an industrial plant Diesel engine.

31. A variable Displacement Diesel engine according to claim wherein said Diesel engine powers heat and air conditioning equipment. *see *see 0 0 0600 00. *0#00 -24- 16/06 '03 MON 11:05 [TX/RX No 9442]