AU2013201827A1

AU2013201827A1 - Rotary combustion engine

Info

Publication number: AU2013201827A1
Application number: AU2013201827A
Authority: AU
Inventors: Maurice ELLIS
Original assignee: Individual
Current assignee: Individual
Priority date: 2012-05-28
Filing date: 2013-03-22
Publication date: 2013-12-12
Also published as: WO2013177613A1

Abstract

A rotary engine (100) including a drum (102), a shaft (104) connected to said drum (102) adapted for rotary motion, propulsion chamber means (106, 108) formed in said drum (102) for receiving a fuel mixture, combustion chamber means (110, 112) external to said 5 drum (102) for ignition of said fuel mixture and exhaust chamber means (117, 119) formed in said drum (102) for expelling burnt fuel from said combustion chamber means (117, 119). The fuel mixture is ignited when said propulsion chamber means (106, 108) overlaps said combustion chamber means (117, 119) in order to rotate said propulsion chamber means (106, 108) thereby rotating said drum (102) and said shaft (104). 113 lIba 1/6i 12C)

Description

ROTARY COMBUSTION ENGINE Field of the Invention This invention relates to a rotary combustion engine. Background of the Invention 5 The existing internal combustion engine (ICE) has internal seals which wear very quickly and therefore need replacing. This is inefficient and costly not only in terms of the replacement needed but the time lost due to such engine not being in use. The conventional internal combustion engine also has the disadvantage of not being balanced. That is, much energy is dissipated where the piston or pistons of the engine are 10 continually opposed to inertia. The amount of torque and power in a ICE is generally limited by the length of the crank and the amount of space available within the engine compartment. In existing jet engines, similar to the operation of a turbine, fuel is compressed and then ignited which in turn produces thrust or kinetic energy in order to propel a 15 vehicle. However such a process is extremely inefficient in that the amount of energy input to the engine only results in 50% to 60% of equivalent energy output. In terms of the energy produced jet engines simply use too much fuel. The present invention seeks to overcome the abovementioned disadvantages and provides an engine which is applicable for many different vehicles, particularly 20 motorcycles, machinery and marine vehicles. The above references to and descriptions of prior proposals or products are not intended to be, and are not to be construed as, statements or admissions of common general knowledge in the art in Australia. 2 Summary of the Invention According to an aspect of the invention, there is provided a rotary engine including: a drum; 5 a shaft connected to said drum adapted for rotary motion; propulsion chamber means formed in said drum for receiving a fuel mixture; combustion chamber means external to said drum for ignition of said fuel mixture; and exhaust chamber means formed in said drum for expelling burnt fuel from said 10 combustion chamber means; wherein said fuel mixture is ignited when said propulsion chamber means overlaps said combustion chamber means in order to rotate said propulsion chamber means thereby rotating said drum and said shaft. The burnt fuel is preferably forced into the exhaust chamber means upon overlap 15 between the exhaust chamber means and the combustion chamber means as the exhaust chamber means rotates with the drum. The rotary engine may further include exhaust duct means positioned externally of the drum for expelling the burnt fuel from the engine upon overlap between the exhaust chamber means and the exhaust duct means. The rotary engine may further 20 include a combustion and exhaust jacket surrounding said drum and containing said combustion chamber means and said exhaust duct means. Preferably the combustion chamber means includes at least one compartment for enabling combustion of the fuel mixture. The engine may further include ignition means in said at least one compartment. 3 The combustion chamber means may have at least two compartments linked by a duct to enable distribution of the fuel mixture for combustion and/or burnt fuel between the compartments. The rotary engine may further include a cooling jacket surrounding the 5 combustion and exhaust jacket containing compressed air for supply to the propulsion chamber means. The compressed air is preferably at a pressure of at least 140psi. The engine preferably further includes an inlet duct for injecting fuel for the fuel mixture into the propulsion chamber means when the inlet duct is aligned with the rotating propulsion chamber means. The engine may include a seal arrangement abutting 10 the cooling jacket to seal the air inside the cooling jacket. The seal arrangement preferably includes one or more fins having apertures therethrough to enable passage of burnt fuel through exhaust shaft means from the exhaust duct means. During a revolution of the drum, the propulsion chamber means preferably receives the fuel mixture and upon further rotation of the drum the fuel mixture is ignited 15 when the propulsion chamber means overlaps with the combustion chamber means in order to maintain rotary movement of the drum and thereafter when the exhaust chamber means overlaps with the combustion chamber means the burnt fuel is removed upon further rotation of the exhaust chamber means. Brief Description of the Drawings 20 A preferred embodiment of the invention will hereinafter be described, by way of example only, with reference to the drawings in which: Figure 1 is a sectional end view of a rotary engine through line A-A of Figure 2 according to an embodiment of the invention; Figure 2 is a sectional side view of the rotary engine of Figure 1; and 4 Figure 3 is a view similar to Figure 2 showing an arrangement for reintroducing pressurised gases from propulsion chambers into a fin seal assembly casting of the engine. Detailed Description of the Preferred Embodiment 5 Referring to Figure 1 there is shown a rotary engine 100 that includes a work drum 102, a shaft 104 connected to the work drum 102 which rotates with the drum 102. Referring also to Figure 2, the engine 100 further includes a pair of diametrically opposed propulsion chambers 106, 108, a pair of diametrically opposed combustion chambers 110, 112 and a pair of diametrically opposed exhaust chambers 117, 119. Air 10 inlet chambers 133, 147 provide openings where air is pumped into respective propulsion chambers 106, 108. Although this embodiment of the engine 100 has a pair of propulsion chambers, combustion chambers and exhaust chambers, the engine 100 may include as many of each of these chambers depending on the particular application and power output 15 required. Each propulsion chamber 106, 108 is located internally of the exterior surface of drum 102 while each combustion chamber 110, 112 is located externally of the external surface of the drum 102. Fin assembly openings 139, 141 are located diametrically opposed about shaft 104 while a pair of exhaust ducts 114 and 116 diametrically opposed 20 about the shaft 104 are located externally of the external surface of the drum 102. The ducts 114, 116 remove burnt gases through respective exhaust pipes 120 and 122. Each of the combustion chambers 110 and 112 together with the exhaust ducts 114, 116 are contained within a combustion and exhaust jacket 105 that surrounds the drum 102. A minimum clearance exists between the working drum 102 and the 25 combustion and exhaust jacket 105 which can require fine machining. This can be 5 aligned with removable shims in between the work drum 102 and the combustion and exhaust jacket 105 during the setting up of the conical bearings. Located around the combustion and exhaust jacket 105 is a cooling jacket 118 which allows air to be supplied under pressure around the drum 102 and the combustion 5 and exhaust jacket 105. The air in the cooling jacket 118 is compressed and is kept at a minimum of 140 psi whereby air is pumped into the cooling jacket 118 and maintained at least at that pressure. Alternatively, apart from supplying the air by a tube or a number of tubes, this can be supplied additionally through a turbo or similar device. The turbo can be running in tandem or alongside the engine 100 in order to supply air at that pressure. 10 A propeller or fan 115 runs off the rotating shaft 104 in order to circulate the air and cool the air within the cooling jacket 118. The supply of air through the turbo and/or separate tubes are essentially one way valves to prevent any air escaping in a reverse direction. This assists in maintaining the pressure at least at 140 psi which is needed in order to supply air to the propulsion chambers 106, 108 when air is mixed and ignited. 15 A seal assembly made up of an inner fin 126, middle fin 128 and outer fin 130 abuts one side of the cooling jacket 118 and more particularly against lip 127 around the shaft 104. These fins can be placed on a sleeve that fits over shaft 104 to abut lip 127. The fin seal assembly enables sealing of the air inside the cooling jacket 118 and also has apertures therethrough for the shafts 120 and 122 to remove burnt gases from the exhaust 20 ducts 114 and 116. The inner fin 126 is made strong enough to prevent loss of compression during combustion and distortion. A lubricated skimmer pad, made of ceramic material, can be built in between the inner fin 126 and the cooling jacket 118 to maintain the predetermined distance between the sleeve and drum 102. With reference to Figure 2 the operation of one cycle of the engine will 25 hereinafter be described. 6 The following description pertains to propulsion chamber 106, combustion chamber 110, exhaust chamber 119 and exhaust duct 114. The same description can be applied to the operation of the propulsion chamber 108, combustion chamber 112 (made up of four chambers 112A, 112B, 112C and 112D), exhaust chamber 117, exhaust duct 5 116, duct 135 and electrical circuit 137. Initially liquid fuel, such as LPG, is injected into the propulsion chamber 106, which has previously been charged with hot air from inlet 133, through inlet duct 132 which then expands to gas. Inlet ducts 132, 135 extends through cooling jacket 118 and the exhaust and combustion jacket. The change from liquid fuel into fuel vapour 10 provides energy to start the engine 100, along with initially compressed air of 140 psi from an electric air compressor. Air will need to be introduced at fan 115 to move combustion chambers 106, 108 onto inlet chambers/ducts 133, 147 respectively to take on the initial charge of air for the start procedure. The compressed air is provided from the cooling jacket 118 to the propulsion chamber 106 through an opening in the 15 combustion and exhaust jacket 105 at air inlet ducts 133, 147 or through ducts 132, 135 from turbo pumps while the engine is running. The liquid petroleum gas can be initially pumped by air, wind or solar energy or any other suitable means and the conversion of this liquid fuel into vapour during the cycle adds this latent energy as well to the energy released by combustion. This liquid fuel can be introduced at timed intervals through the 20 use of a solenoid valve which is controlled by a computer. In other words the correct amount of fuel for the fuellair mix is controlled by computer and high speed oscillations of a solenoid valve. An electric element can be provided at inlet ducts 132, 135 to stop freezing of the ducts if required. The action of the expanded mixture propels or pushes against the forward wall 25 107 of propulsion chamber 106 and when the forward wall 107 is aligned with the left 7 side of the first combustion chamber 1 10A, an electrical circuit 113, in the form of high voltage electrodes, provides a spark or discharge to ignite the fuel/air mixture. When the shaded region, which represents the mixture of air and fuel, of the propulsion chamber 106 is approximately co-existent (overlapping) with the combustion chamber 1 1OA the 5 explosion releases energy which makes the gas within the two chambers 106 and 1 10A propel the propulsion chamber 106 clockwise. The electrical circuit 113 is also connected to each of the other three combustion chambers 110B, 1IOC and 1 OD in order to ignite or bum the fuel/air mixture in those chambers when the propulsion 106 is aligned with the respective combustion chambers. Alternatively the sequence of firing in 10 each of the four combustion chambers 1 10A to 1 IOD can be timed to coincide with the alignment with the propulsion chamber 106. A series of interconnecting tubes 134 enables complete combustion of the fuel and any residual unburnt gas in each of the chambers 11OA to 1 OC to be transferred to chamber 1 IOD and included with unburnt gas in 11OD and thereafter expelled together. The overall volume of the combustion 15 chamber 110 is about ten times that of the propulsion chamber 106 to allow for the expansion of the gas mixture burning. Four chambers 1 OA to IOD are made available to fit within the confines of the combustion and exhaust jacket 105. As the propulsion chamber 106 travels clockwise so too does the following exhaust chamber 119. When the exhaust chamber 119 aligns with each of the 20 combustion chambers 1 10A to 1 OD, due to the lower pressure than compared to when the gas mixture was ignited and the convex base 121 pulls down the burnt gases so that as the exhaust chamber 119 moves in a clockwise direction, the burnt gases in each of the combustion chambers 1 IOA to 1 OD are forced downwardly and carried. Further rotation of the exhaust chamber 119 aligns with the exhaust duct 114 which expels the 25 burnt gas through that duct and out through the exhaust pipe 120 with assistance from 8 cross-flow of compressed air introduced from the cooling jacket through small holes in the fin assembly opening wall on the opposite side of the fin assembly opening from the exhaust duct. Each of the apertures or openings, illustrated by dotted lines 139, 141 in the three fins 126, 128 and 130 are kept open at all times and permit the passing of burnt 5 gas from exhaust duct 114, 116 to exhaust pipes 120, 122. These fins also rotate with the work drum 102. The seal arrangement also guards against the loss of pressurised air located in the cooling jacket 118 near the shaft 104 and any leakage of compression from combustion that is not carried forward to exhaust by the flow of gases during that cycle. A further pair of fin seals 150, 152 is located on the opposite side of drum 102 abutting 10 against the wall of cooling jacket 118. Lubricated skimmer and alignment pads can be fitted in between the fins 126, 128 and 130 (or 150, 152) to centralize the drum 102 in the combustion and exhaust jacket 105. The arrangement shown in Figure 2 has four ignitions per revolution due to the existence of the two propulsion chambers 106 and 108 which are each fired twice per revolution. A three bank model will produce nine 15 ignitions per revolution of the drum 102 where up to 30,000 rpm is expected to be possible. This revolution range may need to be governed to control the power output of the motor to a manageable level. The current internal combustion engines use a sudden increase in pressure followed by a decrease to crank the drive shaft while the jet turbine uses a continuous flow of high pressure gases to produce the drive required. The rotary 20 combustion engine described herein uses both methods of energy conversion and consideration will also have to be given to this governed revolution range to ensure maximum efficiency is achieved from the engine. It is to be noted that as the leading walls of the respective propulsion chambers 106, 108 are just about aligned with the first respective combustion chambers 11OA and 25 1 12A, the trailing exhaust chambers 119 and 117 have expelled about half of the burnt 9 gases through respective exhaust ducts 116 and 114. As propulsion chamber 106 passes exhaust duct 114 it is about to start a new combustion phase, as air is pumped in at air inlet 147 and liquid gas injected at duct 135, as liquid fuel is injected, expanded into a gas and burnt in the next set of combustion chambers I 12A to I 12D. Openings 145 and 5 143 are used to clear the contents of respective propulsion chambers 106 and 108. The entire drum 102, fin seals 126, 128, 130, 150 and 152, combustion and exhaust jacket 105 and the cooling jacket 118 are encased in a solid engine wall or block 136 which is secured to the cooling jacket 118 by fasteners 138. Fasteners 140 and associated housings are adjustable fixings in order to square the work drum 102 with the 10 work shaft 104 and to position the drum 102 inside the combustion and exhaust jacket 105. A pair of laterally adjustable conical bearings 142 centralize the drum 102 and provide the contact between the working components and the outer casing 136. Removable shims can be inserted to ensure correct clearance between the two major components of the motor. Threaded adjusters 146 are provided for loading the bearings 15 and for the positioning of the work drum 102. There would be a need for two additional housings added outside the conical bearing housing to accommodate a set of sturdy needle bearings to manage the centrifugal forces of the motor (not illustrated). Variations in the engine 100 can be accommodated. For example, increasing the size of the drum increasing the fulcrum effect, that is more torque and power can be 20 delivered as the drum rotates shaft 104. The size of the combustion chambers can be increased to allow for a greater volume of residual burnt gas. The propulsion chambers and the combustion chambers will be subject to extremely high temperatures, probably in excess of 1000*C. They will need ceramic inserts to cope with such temperature conditions. The inserts may need to include pegs on their inner surfaces to allow a gap 25 between them and the metal components in order to provide extra insulation for them 10 from the extreme heat. This will also need to be considered in the sizing of the chambers. The exhaust chambers and the area on the drum between the propulsion chambers and the exhaust chambers will need to be considered in the same manner. The leading and closing edges on the openings in the fins 126, 128, 130, 150 and 152 will be 5 subject to the same temperature and will necessitate these components of the seals to be manufactured as a ceramic casting. The engine 100 according to this embodiment provides essentially one moving part, being drum 102. This gives a balanced engine as the drum rotates in a circular motion, unlike the off-centre, reciprocating motion of a piston and crank of an internal to combustion engine. There are no internal seals that are prone to wearing with the present invention. Furthermore, combustion takes place on the outer periphery of the drum 102 and there is no change in direction of any of the components, fighting or acting against inertia. The jet turbine is not suitable for use in motor vehicles as it has a serious power 15 lag caused by the time required for the motor to wind up to a productive torque revolution range and this will not be the case with the rotary combustion engine being described herein. A serious problem with the jet turbine is the concentration of an enormous amount of heat around the main working bearing and this causes a lot of downtime due to 20 high maintenance requirements. The concentration of the heat of combustion is around a periphery of the engine described herein, well away from the main working bearings. Therefore, this makes heat and wear management a minor concern. The currently used internal combustion engine is limited in the type of fuel it can operate on, whereas the engine described herein runs on a range of fuels such as petrol, aviation kerosene, LPG,

II

ethanol, natural gas and any other fuel dependent on fuel delivery systems available or able to be developed. The kinetic energy can be taken from the engine in either a clockwise or anti clockwise direction depending on which end of the web shaft is used. It can be observed 5 from the drawings that there is no lubricating oil within the vicinity of the combustion chamber as there is with the current ICE, thus lessening the opportunity for air pollution. The engine described herein is suitable to be used instead of the currently used two-stroke motor as it is almost as simple but has a much improved power to size ratio and would once again produce large gains in the area of air pollution control. 10 Diesel motors are a major pollution problem when they are not running in perfect or good condition and this would be about 50% of current diesel motors. This problem would be alleviated with the use of the low wear and low maintenance engine described herein. Referring to Figure 3, in addition to, or as an alternative, having openings 145 15 and 143 to clear the contents of respective propulsion chambers 106 and 108, the pressurised gases can be taken from the fin seal assembly casting 154 at opening or end 155 to tube or duct 158 and reintroduced into the casting 154 through the other end 156 of tube 158 in a direction opposite to the flow of gases in the fin seal assembly. This will produce an equal pressure open barrier and thus contain the pressurised gases from the 20 combustion at that point. The tube or duct 158 can include a one-way valve 157 to assist in its operation. The same principle and methodology is applied to casting 153. This will need to be done at different points around the centre of the castings 153 and 154, as indicated by way of example at points 160, 161, to produce an even barrier as shown in Figure 2 by dotted lines. The barrier is shown in Figures 1 and 3. Additional ducting 25 arrangements described above can be used at the lower portion of casting 154 as well. 12

Claims

1. A rotary engine including: a drum; a shaft connected to said drum adapted for rotary motion; 5 propulsion chamber means formed in said drum for receiving a fuel mixture; combustion chamber means external to said drum for ignition of said fuel mixture; and exhaust chamber means formed in said drum for expelling burnt fuel from said combustion chamber means; 10 wherein said fuel mixture is ignited when said propulsion chamber means overlaps said combustion chamber means in order to rotate said propulsion chamber means thereby rotating said drum and said shaft.

2. A rotary engine according to claim 1 wherein the burnt fuel is forced into the exhaust chamber means upon overlap between the exhaust chamber means and the 15 combustion chamber means as the exhaust chamber means rotates with the drum.

3. A rotary engine according to claim 1 or claim 2 further including exhaust duct means positioned externally of the drum for expelling the burnt fuel from the engine upon overlap between the exhaust chamber means and the exhaust duct means.

4. A rotary engine according to claim 3 further including a combustion and exhaust 20 jacket surrounding said drum and containing said combustion chamber means and said exhaust duct means.

5. A rotary engine according to claim 4 wherein the combustion chamber means includes at least one compartment for enabling combustion of the fuel mixture.

6. A rotary engine according to claim 5 further including ignition means in said at 25 least one compartment. 13

7. A rotary engine according to claim 4 or claim 5 wherein the combustion chamber means has at least two compartments linked by a duct to enable distribution of the fuel mixture for combustion and/or burnt fuel between the compartments.

8. A rotary engine according to any one of claims 3 to 7 further including a cooling 5 jacket surrounding the combustion and exhaust jacket containing compressed air for supply to the propulsion chamber means.

9. A rotary engine according to claim 8 wherein the compressed air is at a pressure of at least 140psi.

10. A rotary engine according to claim 8 or claim 9 further including an inlet duct for 10 injecting fuel for the fuel mixture into the propulsion chamber means when the inlet duct is aligned with the rotating propulsion chamber means.

11. A rotary engine according to claim 10 further including a seal arrangement abutting the cooling jacket to seal the air inside the cooling jacket.

12. A rotary engine according to claim 11 wherein the seal arrangement includes one 15 or more fins having apertures therethrough to enable passage of burnt fuel through exhaust shaft means from the exhaust duct means.

13. A rotary engine according to any one of the preceding claims wherein during a revolution of the drum, the propulsion chamber means receives the fuel mixture and upon further rotation of the drum the fuel mixture is ignited when the propulsion chamber 20 means overlaps with the combustion chamber means in order to maintain rotary movement of the drum and thereafter when the exhaust chamber means overlaps with the combustion chamber means the burnt fuel is removed upon further rotation of the exhaust chamber means. 25 14