FR2828711A1 - INTERNAL COMBUSTION, TWO-STROKE CYCLE ENGINE WITH INDEXED OSCILLATING PLATE CONNECTION AND INDEXED COMPRESSOR - Google Patents

Abstract

The invention relates to a two-stroke cycle internal combustion heat engine having a connecting rod with indexed swash plates and an indexed mounted compressor. The two swash plates (15, 16) control the pistons (30, 31, 32) and are fixed at an angle alpha such that the exhaust-side piston (30) is always ahead of the transfer-side piston (31), thereby creating an asymmetry in the transfer/exhaust diagram. The cylinder (4) of the compresser is fixed at an angle beta such that its piston (32) is disposed close to the top dead centre thererof when the transfer ports of the engine cylinder (1) have just been closed by the piston (31). In this way, fresh gases are delivered continuously during the entire transfer phase. As a result, the gas flush is optimised and the engine performs well over a wide rotation speed range. Under certain conditions, the inventive engine, which is light, compact and moderately complex, does not burn oil. Said engine is suitable for motorisation in relation to model making with light vehicles.

Description

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 The present invention relates to a two-cycle internal combustion engine.

 The thermal engines, with two-stroke cycle of classic design called three lights, use the crank rod system as connecting rod. This simple and economical mechanism, although it is the most used on this type of engine, is not the best suited. Indeed, by considering a cylinder and piston couple, it can be seen that said piston combines the functions of the engine piston and the compressor piston, that it opens and that it closes the exhaust and transfer lights. All these functions follow each other in an unchanging chronological order. The diagram representing the opening advance and the closing delay of the exhaust and transfer lights is symmetrical. The sweeping of cool and hot gases is critical, resulting in poor efficiency and a low effective range of rotational speeds.

 The engine, subject of the present invention, by an original architecture, proposes to provide a solution to optimize the scanning of fresh and hot gases. Consequently, to offer a much better efficiency and a greater effective range of rotational speeds.

The first objective is to obtain an asymmetrical diagram in advance at the opening and at the delay at the closing of the exhaust and transfer lights. The second objective is to obtain a continuous blowing of fresh gases throughout the opening period of the transfer lights.

 The first objective is achieved thanks to a linkage to two oscillating plates carried by the same main shaft. The engine pistons are coaxial and head to tail, they are specialized, the engine piston on the exhaust side to open and close the exhaust lights, the engine piston on the transfer side to open and close the lights of

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 transfer. Note: The skirt of the engine pistons never messes up the exhaust and transfer lights. The two oscillating plates are wedged together at an angle a, so that the engine piston on the exhaust side is always ahead of the engine piston on the transfer side, in other words, for an opening angle identical to the exhaust lights and transfer, the exhaust lights will always be open and closed first. This connecting rod assembly with indexed oscillating plates has the following advantages: The diagram in advance at the opening and at the delay at the closing of the exhaust and transfer lights is well asymmetrical. In fact, the transfer lights will still be open, while the exhaust lights will already be closed, implying a judicious choice of the angle a and of the opening angles of the exhaust and transfer lights. Between the moment when the engine piston on the exhaust side has just passed through its top dead center and the moment when the engine piston on the transfer side will go through its top dead center, the volume of the combustion chamber will practically not change. The pistons take up low radial loads. The transfer lights being closed last, a return of a pressure wave by the exhaust device is not necessary and an overfeeding of the engine is possible.

 The use of swashplates as connecting rods is not without causing some problems. The first is to be able to control several pistons. The second is to be able to make an effective connection between the oscillating plates and the connecting rod heads, knowing that on an oscillating plate, there are two remarkable positions where the connecting rod heads have a simple trajectory which is planar and in an arc of a circle. All the other possible hooking positions will give the rod ends a complex trajectory in the shape of an eight in three dimensions.

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The third is to be able to link a piston to a connecting rod whose head has a complex trajectory, in fact, said connecting rod at its oscillating foot with in addition, an effect of alternating rotation along its longitudinal axis. The fourth is to be able to stabilize the plate of a swash plate, so that it does not turn on itself, and that it can take up the tangential forces induced by the thrust of the engine pistons.

 The first problem is solved by the following design of a swash plate. An oscillation ring is machined from an inclined bore, the point of symmetry of said bore being the center of oscillation, said bore being adjusted on the main shaft. A plate carrying on its periphery one or more crank pins, the axis of a crank pin passing through the center of oscillation. A sliding or rolling device forms a connection with a degree of freedom in rotation between the oscillation ring and the plate. The center of gravity of the swash plate is confused, except for tolerance, with its center of oscillation. This design is compact, rigid, balanced and can offer several crankpins per swash plate.

 The second problem is solved by the use of a ball joint with two degrees of freedom in rotation, called a ball joint with guide tracks. A ball joint with guide tracks consists of a spherical ring which adjusts on a crank pin of the plate, of one or two bearings covering the spherical bearing of said spherical ring and the said bearing or bearings being fixed to a connecting rod head. One or both of the bearings are provided with guide tracks, said guide tracks come to adjust on the low or high part or on the low and high parts of the crank pin. The trajectory of said guide tracks takes up the same trajectory but slightly amplified as at the guide part or parts of the crankpin. The guide tracks neutralize a degree of freedom in rotation along the longitudinal axis

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 of a connecting rod while allowing the two remaining degrees of freedom in rotation, an amplitude of rotation at least slightly greater than the angle of oscillation of the oscillating plates. This design stabilizes the rod heads with complex trajectories. The shape taken by the spherical sliding surfaces of the bearings, minimizes the axial play induced by the normal radial play of operation of the ball joint with guide tracks.

 The third problem is solved by a ball joint which is both axial and radial, called a mixed ball joint.

A mixed ball joint has three degrees of freedom in rotation, and can regain strength in all directions. The mixed ball joint consists of a wide-spherical ring and one or two bearings, themselves with large spans, covering said spherical ring. It should be noted that the amplitude of the oscillation of a connecting rod foot of a connecting rod whose head has a complex trajectory is always very low, a few degrees.

 The fourth problem is solved by the use of couples formed by a slide rod and a slide. A sliding rod has two flat and parallel surfaces on either side of its head, said flat surfaces being parallel to the longitudinal axis of said sliding rod. The slide rod is adjusted sliding in a slide. Said slide has two parallel sliding surfaces and opposite, said slide is in the extension of a driving cylinder, it is aligned with the trajectory of the driving pistons, it is placed in a crankcase. The sliding rod and sliding rod couple takes up the positive or negative tangential forces induced by the plate of the swash plate when a driving piston pushes or pulls on said plate, it prevents said plate from turning on itself, thus forcing the oscillation ring to go into rotation.

The couple connecting rod and slide, eliminates only one

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 degree of freedom in translation and leaves only a degree of freedom in rotation, all following the normal to the sliding surfaces. A sliding rod is advantageously linked to the crankpin of the swash plate by a ball joint with guide tracks. This design gives a simple trajectory to the head of the slide rod, making possible a connection by a tubular axis between the driving piston and the foot of said slide rod. Note: It is possible to install two slide rods with their slides by swash plate, noting that the two slide rods must be diametrically opposite.

 The second objective is achieved by the use of a piston compressor which is attached to the engine and whose volume is freely defined. The compressor is set at an angle P relative to the associated engine cylinder, so that said compressor coming or going to end its delivery phase, with its compressor piston still close or on its top dead center, when the piston engine on the transfer side of the engine cylinder associated with said compressor, going from its bottom dead center to its top dead center, will just close the transfer lights. The cylinder of said compressor incorporates an inlet device with free valves and a discharge pipe leading the fresh gases with regard to the transfer lights of the engine cylinder associated with said compressor. The compressor piston is controlled by one of the two oscillating plates. The compressor is attached to one of the crankshaft housings. The axis of the compressor cylinder is parallel to the axis of a driving cylinder. This design with an attached and indexed compressor has the following advantages: The blowing of fresh gas during the entire transfer phase is effective. In fact, the compressor discharge phase begins shortly before the transfer side motor piston opens the transfer ports, said phase

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 discharge end when the transfer side engine piston will completely close the transfer lights. The dead volumes within the compressor and the discharge pipe are low, the reaction to the suction and discharge of fresh gases is very strong.

The filling coefficient is constant over a wide range of rotational speeds. The volume of the compressor being freely defined, said volume will depend on said filling coefficient. The precompression phase is short-lived, the blowing is done at low pressure, the power consumption is reduced.

 The combination of crankshaft linkage with indexed oscillating plates and an indexed attached compressor as they have just been described, does indeed offer an engine having an optimized sweeping of fresh and hot gases.

 The design of the engine as it has just been described above, requires an atypical preparation of said engine. The crankshaft cannot be greased with a lubricant mixed with the fuel, the lubrication must be clean for the crankshaft. The lubricant used for the lubrication of the crankshaft must not reach the combustion chamber or the exhaust and transfer lights. The two engine pistons of the same engine cylinder have the same combustion chamber.

 The first preparation consists in circulating lubricant under low pressure in the crankshaft. Oil transfer rings via hydraulic connections create a tight, rotational connection between the crankshaft housings and the crankshaft, networks of channels drilled in the construction parts of said crankshaft, conduct the lubricant between all the slippery surfaces and to the rolling elements. It should be noted that other lubrication systems can be used, such as, for example, bubbling or projection.

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 The second preparation consists in equipping all the pistons with an oil scraper segment, said segments placed on the engine pistons being always below the exhaust and transfer ports. The third preparation consists in placing a neck nozzle in the center of the engine cylinder. The diameter of the neck is approximately equal to half the diameter of the bore of the engine cylinder. The volume of the neck, therefore by extrapolation of its length, being defined by the volumetric ratio. The combustion chamber thus obtained has a smaller surface area. The narrowing at the neck of the nozzle causes strong turbulence in the combustion chamber when approaching the two engine pistons.

The whole of the description above can be applied to an engine having two possible variants. By naming by motor entity, the association of an engine assembly with a compressor assembly:
The first variant is an engine with a driving entity. A connecting tube must connect the two crankshaft housings to minimize the effects of pressure and depression caused by the rear of the pistons. The engine has a good Power / Weight ratio, it has fewer constructive parts.

 The second variant is an engine with two driving entities. The axes of the drive cylinders and the axis of the main shaft belong to the same plane. There is no connecting tube. The engine has a more constant torque, it allows strong displacements.

 The engine, subject of the present invention can see one of these embodiments as described below with the aid of a detailed example and referenced.

 Figures 1 and 2 are the overall drawings of an engine with a drive unit, spark ignition, direct air cooling. It complies with this

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 invention. Note: the engine block in figure 1 is dissociated from the engine shaft with its connecting rod in figure 2 to make the reading of the drawings clearer.

Figures 3 to 9 are detailed drawings taken from the drawings of Figures 1 and 2
FIG. 10 is a graph which synthesizes the kinematics of the engine as it is drawn and presented from FIG. 1 to 9.

 FIG. 11 is an overall drawing of an engine with two drive units, with spark ignition, with direct air cooling. It is in accordance with the present invention. Note: the engine block is dissociated from the engine shaft with its crankshaft to make the reading of the drawings clearer.

 Referring to Figure 1, Plate 1/6. The engine block essentially consists of: An engine cylinder 1, including the jacket 2 on the exhaust side where the exhaust lights are machined and the jacket 3 on the transfer side where the transfer lights are machined, the central interior part of the driving cylinder 1 is the combustion chamber in the form of a neck nozzle. Of a compressor cylinder 4 wedged at an angle ss, including an inlet with free valves 5 and a delivery pipe 6, said delivery pipe 6 is connected to the engine cylinder 1 with regard to the transfer lights. The compressor cylinder 4 is fixed to the crankcase 7. A connecting tube 8 connects the two crankcases 7 and 9. The slides 10 and 11 are attached and fixed in the crankcases 7 and 9. The covers 12 and 13 support the two bearings of the motor.

 Referring to Figure 2, Plate 1/6. The main shaft consists essentially of: A main shaft 14 on which are adjusted inter alia, the two oscillating plates 15 and 16, said oscillating plates 15 and 16 are separated by two identical spacers 17 and 18,

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 said spacers 17 and 18 are separated by a ring 19 whose tenons are not aligned, it is this ring 19 which gives the angle setting a between the two oscillating plates 15 and 16. Also carried by the main shaft, the front outlet 20 used as a PTO, the rear outlet 21 used by a magnetic flywheel not shown in the drawing also serving as a flywheel. On the two outputs 20 and 21 are adjusted two bearings 22 and 23 forming the bearings of the motor.

 Referring to Figure 2, Plate 1/6. The crankshaft consists essentially of: two oscillating plates 15 and 16 carrying on their crank pins the ball joints with guide tracks 24, 25 and 26, said ball joints with guide tracks 24, 25 and 26 form the connection with on the one hand, the compressor connecting rod 27, the head of which has a complex trajectory, and on the other hand, the two sliding connecting rods 28 and 29, said sliding connecting rods are adjusted sliding in the slides 10 and 11 (fig. 1). An engine piston 30 on the exhaust side, a motor piston 31 on the transfer side and a compressor piston 32. It should be noted that the engine piston 30 on the exhaust side works under severe conditions, unlike the engine piston 31 on the transfer side , it is not cooled by the presence of fresh gases at the transfer lights. The following solution was adopted for the engine piston 30 on the exhaust side, a light alloy body covered by a cap made of cupro-alloy.

 Referring to Figure 3, Plate 2/6. A swash plate consists of: An oscillation ring 33 on which two bearings 34 and 35 are adjusted, said bearings 34 and 35 are adjusted in the plate 36. The two oscillating plates have the same design, except that the swash plate on the transfer side has only one crankpin.

 Referring to Figure 4, Plate 2/6. A ball joint with guide tracks consists of: A spherical ring 37

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 coming to fit on a crank pin of a plate 36 and held in place by a screw 39 via a washer 38. From a first bearing 40 having a protuberance where the guide tracks are machined, the trajectory of the machining of said guide tracks takes the same trajectory but slightly amplified as at the guiding part of the crankpin, the guiding part is the large diameter of the crankpin, the guide tracks adjusting to this large diameter. A second bearing 41 without protuberance but using the same machining of the guide tracks of the first bearing 40, in order to keep the symmetry of the spherical sliding surfaces between the two bearings 40 and 41.

The two bearings thus produced allow a complete rotation along the X axis, a rotation slightly greater than the angle of oscillation along the Y axis, no rotation along the Z axis, the Z axis being the longitudinal axis. a connecting rod. The two bearings 40 and 41 are positioned between them and with respect to the connecting rod by a stud screw 42 which fits between the two bearings 40 and 41 and which is screwed into the connecting rod head. Two threaded rings 42 and 43 are screwed into the connecting rod head and trap the ball joint with guide tracks. All the connecting rod heads are fitted with ball joints with guide tracks according to the same machining and mounting design except for the fact that for the two slide connecting rods 28 and 29, the bearing 40 is replaced by a bearing 41.

 Referring to Figure 5, Plate 3/6. The engine piston assembly is made up of: A slide rod 28 with its two sliding surfaces, equipped with a bearing 44 in which a tubular pin 45 is slidably adjusted, itself adjusted sliding in the engine piston 30, two rods 46 and 47 trap the tubular axis 45 in the engine piston 30. An oil scraper segment 48 retains the oil in the crankcase and a sealing segment 49 contains the gases under pressure in the cylinder

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 engine. The stud screw 42 positions the ball joint with guide tracks. The second engine crew with the same design.

 Referring to Figure 6, Plate 3/6. The compressor piston assembly is made up of: A compressor connecting rod 27 fitted with a spherical ring 50 with a large bearing held in place by a screw 51. Two bearings 52 and 53 with large spherical bearing surfaces cover the spherical ring 50 and are adjusted in the compressor piston 32. The assembly is held in place by six screws 54 via the ring 55, the six screws 54 are screwed in the compressor piston 32. A segment 56 combines the sealing and scraper functions of oil. The scraped oil is discharged to the bearings 52 and 53 by a series of channels coming from drilling. The stud screw 42 positions the ball joint with guide tracks. The compressor connecting rod 27 sees its connecting rod head have a complex trajectory and its connecting rod foot is oscillating. The spherical ring 50 and the two bearings 52 and 53 form a mixed ball joint.

 Referring to Figure 7, Plate 4/6. The lubrication circuit of a connecting rod assembly essentially consists of: An oil connection 57 opening into an oil transfer ring 58. A series of channels coming from drilling directs the lubricant to all the slippery surfaces and the rolling elements of the swash plate. The second swash plate has the same lubrication circuit. The lubricant after use is collected in the crankshaft housings, it is filtered and cooled then returned to the lubrication circuit.

 Referring to Figure 8, Plate 4/6. The combustion chamber forms a neck nozzle, the neck of which is equal to half the diameter of the bore of the engine cylinder 1.

The geometry of the chamber makes it easy to house the candle 59.

 Referring to Figures 9 and 10, Plate 5/6. Numerical values will be used, it is a

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 possible solution among a large number of others, ranging from the slow engine with torque to the fast engine with power, including the economical engine. For the example proposed, the following values were used: An oscillation angle of 150 for the two oscillating plates, a setting to the oscillating plates a = 150, a setting to the compressor P = 110, an opening angle to the lights exhaust OE = 1300, an opening angle to the transfer lights OT = 1150, ro = 0 when the engine piston 30 on the exhaust side is in bottom dead center. Note: the two oscillating plates can have different oscillation angles. The following results are obtained: An advance at the opening of the exhaust lights AOE = 295, an advance at the opening of the transfer lights AOT = 317. 50, that is to say between the opening of the exhaust lights and the opening of the transfer lights, a DOT = 22.5 offset, which gives time for the evacuation of hot gases still under pressure when the exhaust lights open. A delay in closing the exhaust lights RFE = 650, a delay in closing the transfer lights RFT = 72. 50, i.e. between closing the exhaust lights and closing the transfer lights, a DFT offset = 7.5, the period during which fresh gases will continue to be blown into the engine cylinder by the transfer lights, while the exhaust lights will be closed by the engine piston 30 on the exhaust side. Note: there is no specific diagram for the admission period, this being regulated by free valves 5 and therefore variable depending on the engine speeds. The graph in Figure 10 summarizes the kinematics of an engine with a drive unit.

The piston space curve is very close to a sinusoid. The curve [A] in solid line represents the engine piston 30 on the exhaust side, the curve [B] in line

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pointillé représente le piston moteur 31 côté transfert, la courbe [C] en trait mixte représente le piston compresseur 32. La ligne en trait continu [D] représente la hauteur des lumières d'échappement. La ligne en trait pointillé [E] représente la hauteur des lumières de transfert. Le point [F] confirme qu'à la fermeture des lumières de transfert, que le piston compresseur 32 est très proche de son point mort haut. La zone [G] est le lieu où le volume de la chambre de combustion ne varie pratiquement pas, a est l'angle de calage entre les deux plateaux oscillants, ss est l'angle de calage du compresseur.

dotted line represents the drive piston 31 on the transfer side, the curve [C] in dashed line represents the compressor piston 32. The line in solid line [D] represents the height of the exhaust ports. The dotted line [E] represents the height of the transfer lights. Point [F] confirms that when the transfer lights close, that the compressor piston 32 is very close to its top dead center. Zone [G] is the place where the volume of the combustion chamber practically does not vary, a is the setting angle between the two oscillating plates, ss is the setting angle of the compressor.

 Referring to Figure 11, Plate 6/6. It is an engine with two driving entities according to the second variant. To switch from an engine with one drive unit to an engine with two drive units, it suffices to double said drive unit as it has just been presented, to make some minor modifications to the casings, the cylinders and the crankshaft . The axes of the two engine cylinders 1 and 60 and the axis of the main shaft 14 belong to the same plane.

 The motor of the present invention has a manufacture of average complexity, it is light, rigid and compact, it has a good efficiency and a wide effective range of rotational speeds. Its combustion chamber is compatible with a controlled ignition, or a compression ignition, or a compression ignition and hot spot. A careful design of the engine pistons with for example an anti-friction coating, can allow operation without adding lubricant to the fuel, thus, the engine will not burn oil. The present engine may be suitable for the motorization which ranges from model making to light vehicles.

Claims (10)

claims 1: Internal combustion engine, two-cycle cycle characterized on the one hand: By a connecting rod assembly with two oscillating plates (15,16) whose two oscillating plates (15,16) are carried by the same main shaft (14 ) and are wedged together at an angle (a), so that for the same engine cylinder (1), the engine pistons (30,31) being coaxial and head to tail, the engine piston (30) side exhaust is always ahead of the engine piston (31) transfer side, in other words, for an opening angle identical to the exhaust and transfer lights, the exhaust lights will always be open and closed first. On the other hand, by ball joints with guide tracks (24, 25, 26) connecting all the heads of the connecting rods (27, 28, 29) to the crank pins of the oscillating plates (15, 16). On the other hand, by a mixed ball joint (50-52-53) connecting the foot of the compressor rod (27) to its compressor piston (32). On the other hand, by couples formed by a slide rod (28,29) and by a slide (10,11), the slide rod (28,29) being linked to its driving piston (30,31) by a tubular axis ( 45), the sliding rod adjusting sliding in a slide (10,11). On the other hand, by an attached compressor which is set at an angle (ss) relative to the engine cylinder (1) which is associated with it, so that the compressor coming or going to complete its delivery phase, at its compressor piston (32) still close or at its top dead center, when the engine piston (31) on the transfer side of the engine cylinder (1) associated with said compressor, going from its bottom dead center to its top dead center, will just close the transfer lights of said engine cylinder (1). On the other hand, by a lubrication system specific to the connecting rod assembly. On the other hand, by sealing the oil rise on all of the engine pistons (30,31) and compressor (32). And other <Desc / CRUD Page number 15>  part, by a combustion chamber common to the two engine pistons (30,31) taking the form of a neck nozzle.  2: internal combustion engine, two-cycle cycle, according to claim 1, characterized in that a swash plate (15,16) consists of an oscillation ring (33) machined from an inclined bore , the point of symmetry of said bore being the center of oscillation. A plate (36) carrying on its periphery one or more crank pins, the axis of a crank pin passing through the center of oscillation. A sliding or rolling device (34, 35) forming a connection with a degree of freedom in rotation between the oscillation ring (33) and the plate (36). The center of gravity of the swash plate (15,16) being confused, except for tolerance, with its center of oscillation.  3: internal combustion engine, two-cycle cycle, according to claim 1, characterized in that a ball joint with guide tracks (24, 25, 26) consists of a spherical ring (37) coming adjust on a crank pin oscillating plates (15,16), one or two bearings (40,41) adjusted sliding on the spherical bearing of said spherical ring (37). One or both of the bearings (40,41) are provided with guide tracks which adjust on the low or high part or on the low and high parts of said crank pin. The trajectory of said guide tracks takes up the same trajectory but slightly amplified as with the guide part or parts of said crankpin. Said guide tracks neutralize a degree of freedom in rotation along the longitudinal axis (Z) of a slide rod (28,29) or of a compressor rod (27) while allowing the two remaining degrees of freedom in rotation ( axes X, Y), an amplitude of rotation at least slightly greater than the angle of oscillation of the oscillating plates (15, 16). <Desc / Clms Page number 16>  4: internal combustion engine, two-cycle cycle, according to claim l, characterized in that a mixed ball joint consists of a spherical ring (50) with a large span and one or two bearings (52,53 ) themselves with wide spans. Said mixed ball joint allowing an amplitude of oscillation of a few degrees and being able to regain forces in all directions.  5: internal combustion engine, two-cycle cycle, according to claim 1, characterized in that said torque formed by a slide rod (28,29) and a slide (10, 11), has for one part, a slide rod having two plane and parallel surfaces on either side of its head, said surfaces being aligned with the longitudinal axis of said slide rod (28,29) and normal to the axis of the tubular axis (45) of its big end. And for another part, a slide (10, 11) having two planar, parallel and opposite surfaces, said slide being in the extension of a driving cylinder (1), and being aligned with the trajectory of the driving pistons (30, 31). The couple connecting rod slide (28,29) and slide (10, 11), eliminates only one degree of freedom in translation and leaves only one degree of freedom in rotation, the whole, according to the normal to the sliding surfaces .  6 internal combustion engine, two-stroke cycle, according to claim lr characterized in that the attached compressor has its compressor cylinder (4) fixed to one of the crankshaft housings (7) and its compressor piston (32 ) controlled by one of the oscillating plates (15).  7: Internal combustion engine, two-stroke cycle, according to claims 1 and 6, characterized in that the attached compressor integrates into its cylinder <Desc / Clms Page number 17>  compressor (4) an inlet device with free valves (5) and a discharge pipe (6) leading the fresh gases with regard to the transfer lights of the engine cylinder (1) which is associated with said compressor cylinder (4).  8: internal combustion engine, two-cycle cycle, according to claim 1 characterized in that the engine piston (30) on the exhaust side has its light alloy body, said body being covered by a cap made of cupro-alloy.  9: Internal combustion engine, two-cycle cycle, according to any one of claims 1 to 8, characterized in that the first variant of the engine is an engine with a driving entity and a connecting tube (S ) connects the two crankshaft housings (7,9).  10: Internal combustion engine, two-cycle cycle, according to any one of claims 1 to 8, characterized in that the second variant of the engine, is an engine with two motive entities, the axes of the engine cylinders (1 , 60) as well as the axis of the main shaft (14) belonging to the same plane.