GB2325709A

GB2325709A - Combustion-product engine

Info

Publication number: GB2325709A
Application number: GB9809267A
Authority: GB
Inventors: John Lindsay Douglas; John Logan Douglas
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-05-30
Filing date: 1998-04-30
Publication date: 1998-12-02
Anticipated expiration: 2018-04-30
Also published as: GB2325709B; GB9711058D0; GB9809267D0

Abstract

The engine has an induction/compression section 2 and a power/exhaust section 3 linked by a passage containing the combustion chamber 1. The engine may be a modified Vee internal combustion reciprocating-piston engine, fig.1, or a rotary engine, fig.4. The inlet duct 4 from the induction/compression section 2 to the combustion chamber 1 may contain two valves 6, 7 between which a compressed gas reservoir is formed. The outlet duct 5 may have a single valve 8. The rotary version may comprise, for each of the sections 2, 3, a pair of rotors 10, 11 (fig.5), one rotor 10 having a ridge which engages a groove in the other rotor 11. In a modified rotary engine (figs. 6-8) the valve action is replaced by passages 16-18 in the rotors. The duration available for gas movement, mixing and combustion in the combustion chamber 1 can be kept constant even when the revolution rate alters.

Description

A MODIFIED INTERKA1 COMBUSTION ENGINE Over a century ago man invented the combustion engine. At first a fire produced steam for a reaction turbine, then he used a piston n a cylinder to produce useful energy. He discarded the boxers when the fuel was burnt in a cylinder and drove a reciprocating piston. the internal combustion engine blossomed and now is a beautiful machine used worldwide, but unseen problems were developing and are only now being recognised as both urgent and mandatory - pollution and the dearth of fuel.

Pollution is with us locally and worldwide but it is acknowledged that there are other causes of pollution than the internal combustion engine Here both these problems arise in the combustion chamber. The only clean combustion would be with pure oxygen and hydrogen and that is neither practical nor safe. Most of the fuels used are hydrocarbons mixed with elements such as sulphur, air the main source of oxygen contains nitrogen. The power developed by an internal combustion engine depends on the amount of fuel burnt and that depends on the available supply of oxygen, for practical purposes air. In a reciprocating internal combustion engine the only part of the cycle allotted to combustion alone is at Top Dead Centre. To increase this point means infringing on the compression and/or power stage, the conditions in the combustion chamber are critical, ideally the chamber is full of air, compressed to the degree required, the fuel may be already mixed with the air or may be added. The Oxygen of the air must be in molecular contact with the fuel, throughout the chamber, temperature and pressure have ideal values. Combustion is started by a spark or by injection of fuel,the burn should be complete before the power stage starts.

If all the requirements are provided it means that the combustion stage, starting early, infringes into the compression stage and combustion is still proceding during the power stage. it is hoped that this engine will allow for the critical requirements to be satisfied at varying speeds.

According to the present invention there is provided an engine comprising a section for induction and compression (section I/C) and a section for power and exhaust (section P/E) these sections are linked by a combustion chamber or by more than one combustion chamber and share a common drive which may be adjustable so that when the engine rotates through 360- Top Dead Centre (T.D.C.) of section I/C can be different from T.D.C.

section P/E by a fixed or a varying amount, this allows the interval between the compression stage and the power stage to be increased or decreased ; a duct from section I/C to the combustion chamber contains two valves, sited at the ends, between these valves the duct serves as a reservoir for compressed gas ; the use of a reservoir for compressed air avoids the charging of the combustion chamber being determined by the timing of T.D.C. of the induction/compression section, and charging is quick by high pressure air all the time and not by a gradual build up of pressure the the layout of the valves may vary but some form of resevoir is used ; a duct from the combustion chamber to section P/E has one valve ; when all three valves are closed combustion can take place in a closed combustion chamber, the shape of which is decided by that best for combustion and not because of the shape of pistons and valves and where the critical conditions can be controlled ; in particular the duration of combustion depends on the relation of T.D.C. of section I/C to the T.D.C. of section P/E ; combustion can be started by spark our compression, the actual burn is quick, it is estimated that.the flame travels at 2 to 5 kilometres per second and would take a maximum of 1.25 x lO-S seconds to cross a combustion chamber of 5cm. diameter time is needed to move the gases and to distribute and mix the fuel giving molecular contact between oxygen and fuel throughout the chamber in both petrol and diesel production engines combustion may be started 30 before T.D.C. and even then unburnt fuel may appear in the exhaust gases once the burn is satisfactory the valve from the combustion chamber to section P/E opens and the power stage starts, when the combustion chamber has emptied the valve close to the combustion chamber on the duct from section I/C opens and the compressed air held in the duct (reservoir) blows through the combustion chamber scavenging it into the section P/E and so to the exhaust the combustion chamber is then ready to receive another charge with modifications (see example later), one form of the engine could be developed with no valves, no lubrication in the two casings and no radiator ; the use of ceramic or other heat resisting materials for the combustion chamber and other parts subjected to great heat could permit a "hot" engine, not requiring a radiator (see later) ; implementing the invention may take different forms and three examples are described ; some of the points given for one example may be applicable to the others e.g a "hot" combustion chamber Example I Figs. 1, 2, 3 - there is provided an engine comprising a modified Vee internal combustion reciprocating engine fig.l the the number of paired cylinders is not important and any angle between the two banks can be accepted (see later), the great advantage is using a provan design and the availability of parts ; in this type of engine the cylinders are in two banks in a Vee formation with a common crankshaft and crankcase, here a bank is used for an induction/compression section 2 and the other bank for a power/exhaust section 3 the cylinder heads are modified to give the gas flow described ; a pair of cylinder heads one from each bank are bridged by a combustion chamber 1 with an inlet duct 4 from the induction/compression section cylinder, carrying two valves 6 and 7 ; between these the duct functions as a reservoir, an outlet duct 5 from the combustion chamber to the power/exhaust section 3 has one valve ; a downward stroke of the piston in the induction/compression section induces air ideally from a blower, when the piston passes Bottom Dead Centre (B.D.C.), an inlet valve in that cylinder head closes, the two valves 4 in the duct to the combustion chamber open, the exit valve 5 in the duct from the combustion chamber closes, the combustion chamber can now be charged ; as the rising piston reaches the T.D.C. all the valves are shut, the combustion chamber is full of air for combustion, started by ignition or by compresslon, when the burn has proceeded adequately, the exit duct 5 from the combustion chamber to the power/exhaust section opens and the gases start the power stage, the power stage has been delayed by the duration due to the angle of the Vee between the two banks of cylinders (see later) as the power stroke finishes this cylinder head exhaust valve opens, the valve7 close to the combustion chamber in the inlet duct to the combustion chamber also opens allowing the reservoir of compressed air in duct (reservoir) or gallery 4 (see later) to flush through the combustion chamber into the emptying cylinder in the power/exhaust section and through to an exhaust manifold ; some variation in the point and duration of combustion is possible in the timing of the valve and the time of combustion commencing if the angle of the Vee between the two banks of cylinders is not suitable the air compressed by the induction/compression section is blown through a valve (at each cylinder) into a duct or channel common to all the induction/compression section cylinders, in the figures it is represented by duct 4 ; from this shared reservoir of compressed air, air for each combustion chamber is admitted through a valve to that combustion chamber, this arrangement allows wide variations in the angle between the banks for for heat transfer the two banks of cylinders and the combustion chambers would be water cooled as in the original engine but this would utilise a radiator which means lost heat (fuel) a modified design would be similar to that described for a hot engine (see later) no radiator for combustion chamber; lubrication would be that used in the original engine, a turbo compressor and a catalytic converter could be used, a big advantage of this design is that it used known technology and parts are available Svample IS figs. 4, 5 - there is provided a rotary internal combustion engine comprising, a case, a combustion chamber, 1, and rotors ; the case is devided into a section2for induction/compression and a separate section(s) 3 for power/exhaust ; these sections are linked by the combustion chamber, each section contains at least a pair of rotors 10 and 11 cf equal outside diameter, one rotor 10 in each pair consists of a hub with a ridge on its outer surface parallel to the rotor axis, the paired rotor 11 has a groove on its outer surface complementing the ridge, which meshes closely this this arrangement forming a space or cylinder 12 round the hub of the ridge carrying rotor 10 bounded by the close fitting casing and parts of the periphery of the paired rotor 11 so that when the rotors turn through 360 the ridge meshes in the groove at one point namely Top Dead Centre (T.D.C.) ; this point closes the cylinder to permit free rotation the paired rotors are mounted on parallel axes and are synchronised outside the casing ; the drive between section induction/compression and section power/exhaust contains a coupling 9 which can be fixed or automatically operated thus allowing the timing of T.D.C. of the two sections to be different and section power/exhaust 3 can lag behind section induction/compression 2 allowing variation in the duration of the combustion time, the valves to and from the combustion chamber 1 would be activated by the relevant section shaft ; when the engine is running air is induced into the induction/compression section by the ridge as it passes an inlet manifold through the casing to the cylinder, just after T.D.C.

induction continues for almost 360 only being stopped as the ridge nears T.D.C. ; the air substantially cannot pass through the small gap between the rotors at T.D.C., and is compressed by the ridge on the next rotation and passes through an exit manifold through the casing just before T.D.C. this this manifold leads by a duct 4 with two valves 6 and 7 to the combustion chamber, l from from the combustion chamber a duct 5 with a valve communicates with an inlet manifold to the power/exhaust section cylinder ; the induction/compression and power/exhaust sections have similar designs, air flow is through a blower to the inlet manifold of the induction/compression section, the air is compressed and passes through the two valves in the duct 4 to the combustion chamber ; this is isolated between the two sections the valve in the exit duct 5 from the combustion chamber to section power/exhaust is closed and the combustion chamber 1 is charged ; the valves 6 and 7 in the duct 4 to the combustion chamber now close trapping compressed air between them and closing the combustion chamber ; combustion started by ignition or compression 13 commencing in the closed chamber ; after the burn is complete, opening of the exit valve 8 duct 5 allows the hot combustion gases into the power/exhaust section, behind the ridge of that section, starting a power stage : as the power stage ends the exhaust stage starts and the valve 7 close to combustion chamber on the duct 4 from the induction/compression section opens the reservoir allowing a blast of the air to scavenge the combustion chamber into, the emptying power/exhaust section and se to the exhaust manifold ; the valves in the duct to the combustion chamber are timed from the shaft of the induction/compression section ; the valve in the duct from the combustion chamber to the power/exhaust section is timed by the shaft to that section ; further power/exhaust rotors may be added to step the cooling of the exhaust rather like a compound or triple expansion steam engine avoiding a turbine in the exhaust there is a lot of heat to be harvested from the casing and the outside of the combustion chamber and ducts, these would be air cooled and the hot air added at a suitable point in the exhaust system ; if it is possible the combustion chamber, the ducts and valves, rotors and casing could be of ceramic or other heat resisting material and a "hot" engine could be built such a combustion chamber could be cooled by the scavenging air as it flushed the chamber, although this is hot air it is cooler than the gas after combustion, the incoming air of the next charge would not need to be so hot or compressed as the heat gained in cooling the combustion chamber would compensate, a preheat could be fitted to assist starting in cold conditions; such an engine would be built without lubrication in the casing, the rotors and the casing are not in contact and the rotor bearings could be outside the casing or of ceramic type, such an engine would not need a radiator and the exhaust gas would have given up its energy to the extra power/exhaust rotors; xa3le III Figs. 6, 7, 8 - provides a rotary form where the valve action is given by the passage of ducts 16 17 and 18 in the rotors across complimentary ducts and manifolds through the casing in the induction/compression section as the ridge approaches T.D.C. the compressed air in the cylinder passes through two parallel ducts 16 and 17 down to the hub side 20 and across the small gap to the duct 4 to the combustion chamber 1 these ducts are of different size, the first one 1? to open for only a short time is small allowing only enough air down to the combustion chamber to scavenge it and then that opening closes, the larger duct 16 opening later, as the rotor turns allows the cylinder 12 to charge the combustion chamber and then that passage through the gap to the casing is also closed ; in the power/exhaust section the ridged rotor has only one duct 21 which passes from the hub side to the cylinder just after the ridge, as the ridge passes T.D.C., this allows the combusted gases to start the power stage; to allow the combustion chamber to empty completely the lumen of the duct is continued as a groove 23 on the side of that hub, this groove is prolonged long enough to allow the combustion chamber to empty and then allow the scavenging air through the combustion chamber and into the power/exhaust system small all the gaps between the rotors and the casing are as small as possible so that no substantial amount of gas is lost and blow past is minimal ; the rotors are synchronised outside the casing, the drive to the two sections is similar to that of example II so that variation off duration of combustion is retained extra extra power/exhaust sections avoid the need for an exhaust turbine ; engraving or machining the relevant points of blowpast may help to reduce this problem, this engine could be all rotary, no lubrication in the casing, no radiators, economical.

INDEX OF FIGURES Fig. 1: Example I - diagram of Vee engine showing modifications.

Fig. 2: Example I - gas flow.

Fig. 3: Example I - valve action.

Fig. 4: Example II - rotary with valves similar to those of Ex. I.

Fig. 5: Illustration applies to both Example II and III T.D.C. of section induction/compression and of section power/exhaust are different either by a fixed lag or a lag varied by automatic control.

Fig. 6: Example III - using rotors with ducts to provide valve action.

Fig. 7: Example III - sections induction/compression and power/exhaust have paired rotors .. one with a ridged hub and the other with a complementing grooved circumference .. the two mesh and are synchronised outside the casing. Figure 7 shows the ridge carrying rotor of the induction/compression section, where the ridge passing the inlet manifold just after T.D.C.

induce air into the cylinder, 24, and as the air cannot suabstantially pass the gas lock at T.D.C., the air is compressed by the next rotation of the ridge and is forced through ducts 16 and 17 in the rotor down to the hub of the rotor where it can cross the narrow gap to an outlet manifold leading by duct 4 to the combustion chamber (see text for function of ducts 16 and 17).

Fig. 8: Example III - shows the ridged rotor in this power/exhaust section .. combusted gases pass from the combustion chamber through duct 5 to cross the narrow gap to duct 22 (18) in the rotor hub side and so to the cylinder by duct 18 , the combustion chamber is able to continue emptying through groove 23 and this track closes after scavenging has cleared through the combustion chamber.

INDEX OF PARTS 1. Combustion chamber.

2. Induction/compression section .. (may be a bank of cylinders or a pair of rotors).

3. Power/exhaust section . (may be a bank of cylinders or a pair of rotors).

4. Duct from induction/compression section to combustion chamber .. may be enlarged between 5 and 6 valves to form a reservoir shared by all the induction/compression sections cylinders.

5. Duct from combustion chamber to power/exhaust section.

6. Valve, close to induction/compression section, in duct 4.

7. Valve, close to combustion chamber in duct 4.

8. Valve in duct 5.

9. Coupling on drive to induction/compression section from power/exhaust section; may be fixed or variable.

10. Rotor with ridge on the hub . such rotors are in both induction/compression and power/exhaust sections.

11. Rotor with groove on the circumference . such rotors are in both induction/compression and power/exhaust sections.

12. Cylinder round hub ridge bearing rotor.

13. Fuel injector or ignition terminal on combustion chamber.

14. Shaft driving sections induction/compression and power/exhaust.

15. Ridge on rotor hub circumference.

16. Duct from cylinder to side of hub - larger diameter induction compression section, see text.

17. Duct from cylinder to side of hub - smaller diameter induction compression section, see text.

18. Duct from side of hub of ridge carrying rotor to cylinder behind ridge .. power/exhaust section.

19. Circumference of hub of ridge carrying rotor.

20. Side of hub, ridge carrying rotor, in induction/compression section.

21. Side of hub, ridge carrying rotor, in power/exhaust section.

22. Opening of duct 18 on hub side and extended by groove 23.

23. Groove on hub side to extend duct 18.

24. Cylinder .. leading ridge = compression, following ridge = induction.

25. Piston in Vee engine.

26. Air inlet.

27. Exhaust.

Claims

1. According to the present invention there is provided an engine comprising a section for induction and compression (section I/C) and a section for power and exhaust (section P/E) these sections are linked by a combustion chamber or by more than one combustion chamber and share a common drive which may be.

adjustable so that when the engine rotates through 360 Top Dead Centre (T.D.C.) of section I/C can be different from T.D.C.

section P/E by a fixed or a varying amount, this allows the interval between the compression stage and the power stage to be increased or decreased ; a duct from section I/C to the combustion chamber contains two valves, sited at the ends, between these valves the duct serves as a reservoir for compressed gas ; the use of a reservoir for compressed air avoids the charging of the combustion chamber being determined by the timing of T.D.C. of the induction/compression section, and charging is quick by high pressure air all the time and not by a gradual build up of pressure the the layout of the valves may vary but some form of resevoir is used ; a duct from the combustion chamber to section P/E has one valve ; when all three valves are closed combustion can take place in a closed combustion chamber, the shape of which is decided by that best. for combustion and not because of the shape of pistons and valves and where the critical conditions can be controlled ; in particular the duration of combustion depends on the relation of T.D.C. of section I/C to the T.D.C. of section P/E ; combustion can be started by spark or compression, the actual burn is quick, it is estimated that the flame travels at 2 to 5 kilometres per second and would take a maximum of 1.25 x 10-5 seconds to cross a combustion chamber of 5cm. diameter ; time is needed to move the gases and to distribute and mix the fuel giving molecular contact between oxygen and fuel throughout the chamber ; in both petrol and diesel production engines combustion may be started 30 before T.D.C. and even then unburnt fuel may appear in the exhaust gases once the burn is satisfactory the valve from the combustion chamber to section P/E opens and the power stage starts, when the combustion chamber has emptied the valve close to the combustion chamber on the duct from section I/C opens and the compressed air held in the duct (reservoir) blows through the combustion chamber scavenging it into the section P/E and so to the exhaust ; the combustion chamber is then ready to receive another charge with modifications (see example later), one form of the engine could be developed with no valves, no lubrication in the two casings and no radiator the the use of ceramic or other heat resisting materials for the combustion chamber and other parts subjected to great heat could permit a "hot" engine, not requiring a radiator (see later) ; implementing the invention may take different forms and three examples are described some some of the points given for one example may be applicable to the others e.g a "hot" combustion chamber.

2. An internal combustion engine as claimed in claim 1 wherein there is provided means of separating the function of induction/compression from that of power/exhaust such that the duration of each rotation available for the gases and fuel to be moved, mixed to a molecular state of contact can be controlled so that increase in the rate of revolution of the engine does not reduce this duration thereby preventing the desired conditions being provided.

An An internal combustion engine as claimed in claim 1 wherein there is provided an engine comprising a modified Vee internal combustion reciprocating engine, the number of paired cylinders is not important and any angle between the two banks can be accepted, the great advantage is using a provan design and the availability of parts ; in this type of engine the cylinders are in two banks in a Vee formation with a common crankshaft and crankcase, here a bank is used for an induction/compression section 2 and the other bank for a power/exhaust section

3 ; the cylinder heads are modified to give the gas flow described fig. 2 ; a pair of cylinder heads one from each bank are bridged by a combustion chamber 1 with an inlet duct 4 from the induction/compression section cylinder1 carrying two valves 6 and 7 ; between these the duct functions as a reservoir, an outlet duct 5 from the combustion chamber to the power/exhaust section 3 has one valve 6 ; a downward stroke of the piston in the induction/compression section induces air ideally from a blower, when the piston passes Bottom Dead Centre (B.D.C.), an inlet valve in that cylinder head closes, the two valves in the duct 4 to the combustion chamber open, the exit valve 8 in the duct 5 from the combustion chamber closes, the combustion chamber can now be charged ; as the rising piston reaches the T.D.C. all the valves are shut, the combustion chamber is full of air for combustion, started by ignition or by compression, when the burn has proceeded adequately, the exit duct 5 from the combustion chamber to the power/exhaust section opens and the gases start the power stage, the power stage has been delayed by the duration due to the angle of the Vee between the two banks of cylinders (see later) ; as the power stroke finishes this cylinder head exhaust valve opens, the valve7 close to the combustion chamber in the inlet duct to the combustion chamber also opens allowing the reservoir of compressed air in duct (reservoir) or gallery 4 (see later) to flush through the combustion chamber into the emptying cylinder in the power/exhaust section and through to an exhaust manifold ; some variation in the point and duration of combustion is possible in the timing of the valve and the time of combustion commencing ; if the angle of the Vee between the two banks of cylinders is not suitable the air compressed by the induction/compression section is blown through a valve (at each cylinder) into a duct or channel common to all the induction/compression section cylinders, in the figures it is represented by duct 4 from from this shared reservoir of compressed air, air for each combustion chamber is admitted through a valve to that combustion chamber, this arrangement allows wide variations in the angle between the banks ; for heat transfer the two banks of cylinders and the combustion chambers would be water cooled as in the original engine but this would utilise a radiator which means lost heat (fuel) a modified design would be similar to that described for a hot engine (see later) no radiator for combustion chamber; lubrication would be that used in the original engine, a turbo compressor and a catalytic converter could be used, a big advantage of this design is that it used known technology and parts are available.

4. An internal combustion engine as claimed in claim 1 and claim 2 wherein there is provided, figs. 4 and 5, a rotary internal combustion engine comprising, a case, a combustion chamber, 1, and rotors ; the case is divided into a section 2 for induction/compression and a separate section(s) 3 for power/exhaust ; these sections are linked by the combustion chamber, each section contains at least a pair of rotors 10 and 11 of equal outside diameter, one rotor 10 in each pair consists of a hub with a ridge on its outer surface parallel to the rotor axis, the paired rotor 11 has a groove on its outer surface complementing the ridge, which meshes closely ; this arrangement forming a space or cylinder 12 round the hub of the ridge carrying rotor 10 bounded by the close fitting casing and parts of the periphery of the paired rotor 11 so that when the rotors turn through 360 the ridge meshes in the groove at one point namely Top Dead Centre (T.D.C.) ; this point closes the cylinder to permit free rotation the paired rotors are mounted on parallel axes and are synchronised outside the casing ; the drive between section induction/compression and section power/exhaust contains a coupling 9 which can be fixed or automatically operated thus allowing the timing of T.D.C. of the two sections to be different and section power/exhaust 3 can lag behind section induction/compression 2 allowing variation in the duration of the combustion time, the valves to and from the combustion chamber 1 would be activated by the relevant section shaft when the engine is running air is induced into the induction/compression section by the ridge as it passes an inlet manifold through the casing to the cylinder, just after T.D.C.

induction continues for almost 360 only being stopped as the ridge nears T.D.C. ; the air substantially cannot pass through the small gap between the rotors at T.D.C., and is compressed by the ridge on the next rotation and passes through an exit manifold through the casing just before T.D.C. ; this manifold leads by a duct 4 with two valves 6 and 7 to the combustion chamber, 1 ; from the combustion chamber a duct 5 with a valve 8 communicates with an inlet manifold to the power/exhaust section cylinder ; the induction/compression and power/exhaust sections have similar designs, air flow is through a blower to the inlet manifold of the induction/compression section, the air is compressed and passes through the two valves in the duct 4 to the combustion chamber ; this is isolated between the two sections the valve in the exit duct 5 from the combustion chamber to section power/exhaust is closed and the combustion chamber 1 is charged ; the valves 6 and 7 in the duct 4 to the combustion chamber now close trapping compressed air between them and closing the combustion chamber ; combustion started by ignition or compression 13 commencing in the closed chamber ; after the burn is complete, opening of the exit valve 8 duct 5 allows the hot combustion gases into the power/exhaust section, behind the ridge of that section, starting a power stage : as the power stage ends the exhaust stage starts and the valve 7 close to combustion chamber on the duct 4 from the induction/compression section opens the reservoir allowing a blast of the air to scavenge the combustion chamber into, the emptying power/exhaust section and so to the exhaust manifold ; the valves in the duct to the combustion chamber are timed from the shaft of the induction/compression section ; the valve in the duct from the combustion chamber to the power/exhaust section is timed by the shaft to that section ; further power/exhaust rotors may be added to step the cooling of the exhaust rather like a compound or triple expansion steam engine avoiding a turbine in the exhaust there is a lot of heat to be harvested from the casing and the outside of the combustion chamber and ducts, these would be air cooled and the hot air added at a suitable point in the exhaust system ; if it is possible the combustion chamber, the ducts and valves, rotors and casing could be of ceramic or other heat resisting material and a "hot engine could be built such a combustion chamber could be cooled by the scavenging air as it flushed the chamber, although this is hot air it is cooler than the gas after combustion, the incoming air of the next charge would not need to be so hot or compressed as the heat gained in cooling the combustion chamber would compensate, a preheat could be fitted to assist starting in cold conditions; such an engine would be built without lubrication in the casing, the rotors and the casing are not in contact and the rotor bearings could be outside the casing or of ceramic type, such an engine would not need a radiator and the exhaust gas would have given up its energy to the extra power/exhaust rotors.

5. An internal combustion engine as claimed in claims 3 and 4 wherein is provided a reservoir to contain the compressed air delivered by the Induction/Compression section; such a reservoir Cor duct) being common to all the Induction/Compression sections means the charging of a combustion chamber can be carried out by compressed air immediately the relevant pathway opens - quickly filling the combustion chamber (which in many engines is only 50% full of air) and taking less time the combustion chambers are not served/charged by one Induction/Compression unit only thus allowing more freedom in timing the combustion point.

6. An internal combustion engine as claimed in claims 1,3 and 4 wherein there is provided means of controlling the conditions of combustion as it takes place in a dedicated isolated chamber; it is accepted that some 25% of the energy supplied to such an engine is lost by the need to cool the combustion area; this energy has to be conducted from the inside of the chamber through the wall and disipated by a radiator; we claim that the heat lost should not leave the inside of the combustion chamber but should be absorbed, by heating the incoming fresh charge of air; in the designs suggested the combustion chamber is scavenged by compressed air which gives energy to the Power/Exhaust section; this scavenging air is hot but not at temperature of combusted gas and will start the cooling of the combustion chamber, further cooling is given by the fresh charge of air to fill the combustion chamber; this charge for combustion to take place needs to be hot but this heat should be from cooling the combustion chamber from the inside; a smaller combustion chamber and a smaller quantity of fuel would be required and no radiator.

7. An internal combustion engine as claimed in claim 1 wherein there is provided, figs. 6,7 and 8, a rotary internal combustion engine comprising a case, a combustion chamber and rotors and where the valve action is provided by the.passage of ducts in the rotor hubs across complimentary ducts and manifolds through the casing ; the case is divided into a section for Induction/Compression and a separate section for Power/Exhaust, these sections are linked by the combustion chamber and a drive each section contains at least a pair of rotors, fig. 5, 10 and 11, of equal outside diameter, one rotor in each pair consists of a hub with a ridge on its outer surface parallel to the rotor axis, the paired rotor has a groove on the outer surface complementing the ridge which meshes closely, this arrangement forming a space or cylinder round the hub of the ridge carrying rotor bounded by the close fitting case and parts of the periphery of the paired rotor so that when the rotors turn through 360 the ridge meshes in the groove at one point namely Top Dead Centre (T.D.C.), this point closes the cylinder ; to allow free rotation the paired rotors are mounted on parallel axes and are synchronised outside the casing ; the drive between section Induction/Compression and section Power/Exhaust contains a coupling which can be fixed or automatically operated allowing the timing of T.D.C. of the two sections to be different and section Power/Exhaust can lag behind section Induction/Compression allowing variation in the duration of the combustion time, the valve action is provided by the passage of ducts in the relevant ridged rotor hubs, figs 7 and 8, across complementing ducts and manifolds through the casing ; as there are no valves there is no compressed air reservoir as claimed in claim 5.

8. An internal combustion engine as claimed in claim 1 wherein is provided means of increasing the efficiency of the Power/Exhaust section of the rotary type of engine described the paired rotors in the section Power/Exhaust can be repeated allowing the exhaust gases to expand further whilst still compressed and hot ; this will also mean that this type of engine would have a power output over 3604.

9. A rotary internal combustion engine as claimed in claim 1, claim 4 and claim 7 wherein no lubrication within the casing of Induction/Compression or Power/Exhaust sections is needed as there is no contact between rotors and the casing. The necesssary bearings can be sited outside the casing.

10. An internal combustion engine substantially as described herein with reference to figures 1 to 8 of the accompaning drawings.