Axial internal combustion engine Duke Engine

We are accustomed to the classic design of internal combustion engines, which, in fact, has existed for a century. The rapid combustion of the combustible mixture inside the cylinder leads to an increase in pressure, which pushes the piston. That, in turn, turns the shaft through the connecting rod and crank.

Classic internal combustion engine

If we want to make the engine more powerful, first of all we need to increase the volume of the combustion chamber. By increasing the diameter, we increase the weight of the pistons, which negatively affects the result. By increasing the length, we lengthen the connecting rod and increase the size of the entire engine as a whole. Or you can add cylinders - which, naturally, also increases the resulting engine volume.

ICE engineers for the first aircraft encountered such problems. They eventually came up with a beautiful "star" engine design, where the pistons and cylinders are arranged in a circle relative to the shaft at equal angles. Such a system is well cooled by air flow, but it is very large. Therefore, the search for solutions continued.

In 1911, the Macomber Rotary Engine Company of Los Angeles introduced the first of the axial (axial) internal combustion engines. They are also called “barrel” engines, engines with a swinging (or oblique) washer. The original design allows the pistons and cylinders to be placed around the main shaft and parallel to it. The rotation of the shaft occurs due to a swinging washer, which is alternately pressed by the piston connecting rods.

The Macomber engine had 7 cylinders. The manufacturer claimed that the engine was capable of operating at speeds from 150 to 1500 rpm. At the same time, at 1000 rpm it produced 50 hp. Made from materials available at the time, it weighed 100 kg and measured 710 x 480 mm. Such an engine was installed in pioneer aviator Charles Francis Walsh's plane, Walsh's Silver Dart.

The brilliant and slightly crazy engineer, inventor, designer and businessman John Zachariah DeLorean dreamed of building a new automobile empire to counter the existing ones, and making a completely unique “dream car.” We all know the DMC-12, which is simply called the DeLorean. Not only did it become a screen star in the movie “Back to the Future,” but it was also distinguished by unique solutions in everything from an aluminum body on a plexiglass frame to gullwing doors. Unfortunately, against the backdrop of the economic crisis, the production of the car did not justify itself. And then DeLorean had a long trial on a false drug case.

But few people know that DeLorean wanted to complement the unique appearance of the car with a unique engine - among the drawings found after his death were drawings of an axial internal combustion engine. Judging by his letters, he conceived of such an engine back in 1954, and began development seriously in 1979. The DeLorean engine had three pistons, and they were arranged in an equilateral triangle around the shaft. But each piston was double-sided - each end of the piston had to work in its own cylinder.

Drawing from DeLorean's notebook

For some reason, the birth of the engine did not take place - perhaps because developing a car from scratch turned out to be a rather complicated undertaking. The DMC-12 was equipped with a 2.8-liter V6 engine Peugeot developments, Renault and Volvo with a capacity of 130 hp. With. An inquisitive reader can study scans of DeLorean's drawings and notes on this page.

Exotic option axial motor- “Trebent engine”

However, such engines were not widely used - in large aviation there was gradually a transition to turbojet engines, and in cars to this day a scheme is used in which the shaft is perpendicular to the cylinders. The only interesting thing is why such a scheme did not take root in motorcycles, where compactness would come in handy. Apparently they failed to offer any significant benefit over the design we are used to. Now such engines exist, but they are installed mainly in torpedoes - due to how well they fit into the cylinder.

A variant called "Cylindrical Energy Module" with double-sided pistons. Perpendicular rods in the pistons describe a sinusoid, moving along a wavy surface

The main distinguishing feature of an axial internal combustion engine is its compactness. In addition, its capabilities include changing the compression ratio (combustion chamber volume) simply by changing the angle of the washer. The washer swings on the shaft thanks to a spherical bearing.

However, the New Zealand company Duke Engines presented its modern version of the axial internal combustion engine in 2013. Their unit has five cylinders, but only three fuel injection nozzles and not a single valve. Also interesting feature motor is the fact that the shaft and washer rotate in opposite directions.

Not only the washer and shaft rotate inside the engine, but also a set of cylinders with pistons. Thanks to this, it was possible to get rid of the valve system - at the moment of ignition, the moving cylinder simply passes by the hole where fuel is injected and where the spark plug is located. During the exhaust stage, the cylinder passes by the gas outlet.

Thanks to this system, the number of required spark plugs and injectors is less than the number of cylinders. And per revolution there are a total of the same number of piston strokes as in a 6-cylinder engine of conventional design. At the same time, the weight of the axial motor is 30% less.

In addition, engineers from Duke Engines claim that the compression ratio of their engine is superior to conventional analogues and is 15:1 for 91 gasoline (for standard automotive internal combustion engines this figure is usually 11:1). All these indicators can lead to a reduction in fuel consumption, and, as a result, to a reduction in the harmful effects on environment(or to increase engine power - depending on your goals).

The company is now developing the engines for commercial use. In our age of mature technologies, diversification, economies of scale, etc. It’s hard to imagine how you can seriously influence the industry. Duke Engines apparently understands this too, and therefore intends to offer its engines for powerboats, generators and small aircraft.

Duke engine low vibration demonstration

The invention can be used in engine building. The internal combustion engine includes at least one cylinder module. The module includes a shaft having a first multi-lobe cam axially mounted on the shaft, a second adjacent multi-lobe cam, and a differential gear drive to the first multi-lobe cam for rotation about an axis in the opposite direction about the shaft. The cylinders of each pair are located diametrically opposite to the shaft with cams. The pistons in a pair of cylinders are rigidly interconnected. Multi-lobe cams have 3+n lobes, where n is zero or an even integer. The reciprocating motion of the pistons in the cylinders imparts rotational motion to the shaft through the connection between the pistons and the surfaces of the cams with several working lobes. The technical result is to improve torque and engine cycle control characteristics. 13 salary f-ly, 8 ill.

The invention relates to internal combustion engines. In particular, the invention relates to internal combustion engines with improved control of various cycles during engine operation. The invention also relates to internal combustion engines with higher torque characteristics. Internal combustion engines used in automobiles are typically reciprocating engines in which a piston oscillating in a cylinder drives a crankshaft through a connecting rod. There are numerous disadvantages in the traditional piston engine design with crank mechanism, the disadvantages are mainly due to the reciprocating motion of the piston and connecting rod. Numerous engine designs have been developed to overcome the limitations and disadvantages of traditional crank-type internal combustion engines. These developments include rotary engines, such as the Wankel engine, and engines in which a cam or cams are used instead of at least crankshaft and in some cases also the connecting rod. Internal combustion engines in which a cam or cams replace the crankshaft are described, for example, in Australian Patent Application No. 17897/76. However, while advances in this type of engine have made it possible to overcome some of the disadvantages of traditional crank-type piston engines, engines using a cam or cams instead of a crankshaft have not been used to their full extent. There are also cases of using internal combustion engines with counter-moving interconnected pistons. A description of such a device is given in Australian patent application No. 36206/84. However, neither this subject matter disclosure nor similar documents suggest that the concept of counter-moving interlocking pistons can be used in conjunction with anything other than a crankshaft. The objective of the invention is to create a cam internal combustion engine rotary type, which can have improved torque and more high performance engine cycle management. The object of the invention is also to create an internal combustion engine, which makes it possible to overcome at least some of the disadvantages of existing internal combustion engines. In a broad sense, the invention provides an internal combustion engine including at least one cylinder module, said cylinder module comprising: a shaft having a first multi-lobe cam axially mounted on the shaft, and a second adjacent multi-lobe cam. and a differential gear drive to the first cam with several working projections for rotation around an axis in the opposite direction about the shaft; - at least one pair of cylinders, the cylinders of each pair are located diametrically opposite to the shaft with cams with several working projections that are inserted between them; - a piston in each cylinder, pistons in a pair of cylinders are rigidly interconnected; wherein the multi-lobe cams comprise 3+n lobes, where n is zero or an even integer; and in which the reciprocating motion of the pistons in the cylinders imparts rotational motion to the shaft through the connection between the pistons and the surfaces of the multi-lobe cams. The engine can contain from 2 to 6 cylinder modules and two pairs of cylinders per cylinder module. Pairs of cylinders can be located at an angle of 90 o to each other. Advantageously, each cam has three lobes, and each lobe is asymmetrical. The rigid piston coupling includes four connecting rods extending between a pair of pistons with connecting rods equally spaced around the periphery of the piston, the connecting rods being provided with guide bushings. The differential gear can be mounted inside the engine with reverse rotating cams, or on the outside of the engine. The engine may be a two-stroke engine. In addition, the connection between the pistons and the surfaces of the multi-lobe cams is carried out through roller bearings, which may have common axis, or their axes can be offset relative to each other and the piston axis. From the above, it follows that the crankshaft and connecting rods of the conventional internal combustion engine are replaced by a linear shaft and multi-lobe cams in the engine according to the invention. Using a cam instead of a connecting rod/crankshaft arrangement allows for more effective control of piston positioning during engine operation. For example, the period at which the piston is at top dead center (TDC) can be extended. Next from detailed description According to the invention, despite the presence of two cylinders in at least one pair of cylinders, in reality a double-acting cylinder-piston device is created using opposing cylinders with interconnected pistons. The rigid piston interconnection also eliminates distortion and minimizes contact between the cylinder wall and the piston, thereby reducing friction. The use of two counter-rotating cams makes it possible to achieve higher torque than with traditional internal combustion engines. This is because as soon as the piston begins its power stroke, it has maximum mechanical advantage over the lobe of the cam. Turning now to more specific details of internal combustion engines in accordance with the invention, such engines, as indicated above, include at least one cylinder module. An engine with one cylinder module is preferred, although engines can have two to six modules. In motors with multiple modules, a single shaft passes through all modules either as a single element or as interconnected shaft parts. Likewise, cylinder blocks of engines with multiple modules can be formed integrally with each other or separately. A cylinder module usually has one pair of cylinders. However, engines according to the invention can also have two pairs of cylinders per module. In cylinder modules having two pairs of cylinders, the pairs are typically located at an angle of 90° to each other. With regard to multi-lobe cams in engines according to the invention, a three-lobe cam is preferred. This allows for six ignition cycles per cam revolution in a two-stroke engine. However, engines can also have cams with five, seven, nine, or more lobes. The cam lobe can be asymmetrical to control piston speed at a particular stage of the cycle, for example to increase the time the piston remains at top dead center (TDC) or bottom dead point (BDC). It is estimated by those skilled in the art that increasing the duration at top dead center (TDC) improves combustion, while increasing the duration at bottom dead center (BDC) improves scavenging. By adjusting the piston speed using the working profile, it is also possible to adjust the piston acceleration and torque application. In particular, this makes it possible to obtain more torque immediately after top dead center than in a traditional piston engine with a crank mechanism. Other design features, provided by variable piston speed, include regulation of the opening speed of the bore in relation to the closing speed and regulation of the compression speed in relation to the combustion speed. The first multi-lobe cam may be mounted to the shaft by any method known in the art. Alternatively, the shaft and first cam with multiple lobes can be manufactured as a single element. The differential gearing, which enables reverse rotation of the first and second multi-lobe cams, also synchronizes the reverse rotation of the cams. The cam differential gearing method may be any method known in the art. For example, the bevel gears may be mounted on opposing surfaces of the first and second cams with multiple lugs with at least one gear therebetween. Preferably, two diametrically opposed gears are installed. A support element in which the shaft rotates freely is provided for the support gears, which provides certain advantages. The rigid coupling of the pistons typically includes at least two connecting rods that are mounted between them and secured to the bottom surface of the pistons adjacent to the periphery. Preferably, four connecting rods are used, equally spaced around the periphery of the piston. The cylinder module contains guide bushings for the connecting rods that interconnect the pistons. Guide bushings are typically configured to allow lateral movement of the connecting rods as the piston expands and contracts. The contact between the pistons and the cam surfaces helps reduce vibration and friction losses. There is a roller bearing on the underside of the piston to contact each cam surface. It should be noted that the interconnection of the pistons, including a pair of counter-moving pistons, allows the clearance between the contact area of ​​the piston (whether a roller bearing, carriage, or the like) and the cam surface to be adjusted. Moreover, this method of contact does not require grooves or the like in the side surfaces of the cams to produce a traditional connecting rod, as is the case with some engines of similar design. This characteristic engines of a similar design when overspeeding leads to wear and excessive noise, these disadvantages are largely eliminated in the present invention. The engines according to the invention can be two-stroke or four-stroke. In the first case, the fuel mixture is usually supplied with supercharging. However, any type of fuel and air supply can be used together in a four-stroke engine. The cylinder modules according to the invention can also serve as air or gas compressors. Other aspects of the engines of the invention correspond to what is generally known in the art. However, it should be noted that only a very low pressure oil supply is required to the differential gearing of the multi-lobe cams, thus reducing power loss by oil pump. Moreover, other engine components, including pistons, may receive oil through splashing. In this regard, it should be noted that spraying oil onto the pistons using centrifugal force also serves to cool the pistons. The advantages of the motors according to the invention include the following: the motor has a compact design with few moving parts; - engines can operate in any direction when using cams with several symmetrical working projections; - engines are lighter than traditional ones piston engines with a crank mechanism; - engines are more easily manufactured and assembled than traditional engines;
- a longer break in piston operation, which is made possible by the design of the engine, makes it possible to use a lower compression ratio than usual;
- parts with reciprocating motion, such as connecting rods of the piston-crank shaft, have been eliminated. Further advantages of the engines according to the invention due to the use of multi-lobe cams are the following: the cams can be more easily manufactured than crankshafts; cams do not require additional counterweights; and the cams double the action as a flywheel, thus providing more motion. Having considered the invention in a broad sense, we now give specific examples of the invention with reference to the accompanying drawings, which are briefly described below. Fig. 1. Cross-section of a two-stroke engine, including one cylinder module with a cross-section along the cylinder axis and a cross-section with respect to the engine shaft. Fig. 2. Part of the cross section along line A-A of Fig. 1. Fig. 3. Part of the cross section along line B-B of Fig. 1 showing detail of the lower part of the piston. Fig. 4. Graph showing the position of a specific point on the piston when crossing one asymmetrical lobe of the cam. Fig. 5. Part of the cross section of another two-stroke engine, including one cylinder module with a cross section in the plane of the central shaft of the engine. Fig. 6. End view of one of the engine gear blocks shown in FIG. 5. Fig. 7. Schematic view of a part of the engine, showing the piston in contact with the three-lobe cams, which rotate in the reverse direction. Fig. 8. Part of the piston having bearings in contact with the offset cam. Identical positions on the figures are numbered identically. In fig. 1 shows a two-stroke engine 1 including one cylinder module which has one pair of cylinders consisting of cylinders 2 and 3. Cylinders 2 and 3 have pistons 4 and 5 which are interconnected by four connecting rods, two of which are visible at positions 6a and 6b . The engine 1 also includes a central shaft 7, to which cams with three working projections are connected. Cam 9 is actually the same as cam 8 as shown in the figure due to the pistons being at top dead center or bottom dead center. Pistons 4 and 5 contact cams 8 and 9 via roller bearings, the position of which is generally indicated by positions 10 and 11. Other design features of engine 1 include a water jacket 12, spark plugs 13 and 14, oil sump 15, sensor 16 oil pump and balance shafts 17 and 18. The location of the intake ports is indicated by positions 19 and 20, which also corresponds to the position of the exhaust ports. In fig. 2 shows in more detail the cams 8 and 9 together with the shaft 7 and the differential gear, which will be briefly described. The cross section shown in FIG. 2, rotated 90 o with respect to FIG. 1 and the cam lobes are in a slightly different position compared to the positions shown in FIG. 1. Differential or synchronizing gear includes bevel gear 21 on the first cam 8, a bevel gear 22 on the second cam 9, and drive gears 23 and 24. The drive gears 23 and 24 are supported by a gear support 25, which is attached to the shaft housing 26. The shaft housing 26 is preferably part of a cylinder module. In fig. 2 also shows the flywheel 27, pulley 28 and bearings 29-35. The first cam 8 is substantially integral with the shaft 7. The second cam 9 can rotate in the opposite direction to the cam 8, but is time-controlled to the rotation of the cam 8 by a differential gear. In fig. 3 shows the underside of the piston 5 shown in FIG. 1 to introduce the detail of roller bearings. In fig. 3 shows a piston 5 and a shaft 36 extending between the bosses 37 and 38. Roller bearings 39 and 40 are mounted on the shaft 36, which correspond to the roller bearings as indicated by numerals 10 and 11 in FIG. 1. The interconnected connecting rods can be seen in cross section in FIG. 3, one of them is indicated by position 6a. Shown are the couplings through which the interconnected connecting rods pass, one of which is indicated at 41. Although FIG. 3 is made on a larger scale than FIG. 2, it follows that the roller bearings 39 and 40 can come into contact with the surfaces 42 and 43 of the cams 8 and 9 (Fig. 2) during engine operation. The operation of the engine 1 can be assessed from FIG. 1. The movement of piston 4 and 5 from left to right during the power stroke in cylinder 2 causes rotation of cams 8 and 9 through their contact with roller bearing 10. As a result, a “scissors” effect occurs. Rotation of cam 8 causes rotation of shaft 7, while reverse rotation of cam 9 also causes rotation of cam 7 via differential gearing (see FIG. 2). Thanks to the scissor action, more torque is achieved during the power stroke than in a traditional engine. Indeed, the piston diameter/piston stroke ratio shown in FIG. 1 can strive for a significantly larger configuration area while maintaining adequate torque. Another design feature of the engines in accordance with the invention, shown in FIG. 1, is that the equivalent of the crankcase is sealed against the cylinders, unlike traditional two-stroke engines. This makes it possible to use fuel without oil, thus reducing the components released into the air by the engine. The piston speed control and duration at Top Dead Center (TDC) and Bottom Dead Center (BDC) when using an asymmetrical cam lobe are shown in FIG. 4. Fig. 4 is a graph of a specific point on the piston as it oscillates between midpoint 45, top dead center (TDC) 46, and bottom dead center (BDC) 47. Thanks to the lobe of the asymmetrical cam, the speed of the piston can be adjusted. First, the piston remains at top dead center 46 for a longer period of time. The rapid acceleration of the piston at position 48 allows for higher torque during the combustion stroke, while more low speed The piston in position 49 at the end of the combustion stroke allows for more efficient bore adjustment. On the other hand, more high speed the piston at the beginning of the compression stroke 50 allows for faster closure for improved fuel economy, while the low piston speed at the end 51 of this stroke provides greater mechanical benefits. In fig. 5 shows another two-stroke engine having a single-cylinder module. The engine is shown in partial cross section. In fact, half the engine block has been removed to show internal part engine. The cross section is a plane coinciding with the axis of the central engine shaft (see below). Thus, the engine block is divided along the centerline. However, certain engine components are also shown in cross section, such as pistons 62 and 63, bearing bosses 66 and 70, triple lobe cams 60 and 61, and a bushing 83 associated with cam 61. All of these items will be discussed below. Engine 52 (FIG. 5) includes a block 53, cylinder heads 54 and 55, and cylinders 56 and 57. A spark plug is included in each cylinder head but is not shown in the drawing for clarity. The shaft 58 is rotatable in a block 53 and is supported by roller bearings, one of which is indicated at 59. The shaft 58 has a first three-lobe cam 60 attached thereto, the cam located adjacent a three-lobe cam 61 that rotates in the opposite direction. . Engine 52 includes a pair of rigidly interconnected pistons 62 in cylinder 56 and 63 in cylinder 57. Pistons 62 and 63 are connected by four connecting rods, two of which are indicated at 64 and 65. (Connecting rods 64 and 65 are in a different plane from the rest parts of the cross section of the drawing. Likewise, the contact points of the connecting rods and pistons 62 and 63 are not in the same plane of the rest of the cross section. The relationship between the connecting rods and pistons is essentially the same as for the engine shown in Fig. 1. -3). The bridge 53a extends within the block 53 and includes holes through which the connecting rods pass. This bridge holds the connecting rods and, therefore, the pistons in line with the axis of the cylinder module. Roller bearings are inserted between the undersides of the pistons and the surfaces of the three lobe cams. With respect to the piston 62, a support boss 66 is mounted on the underside of the piston, which supports a shaft 67 for roller bearings 68 and 69. The bearing 68 contacts the cam 60, while the bearing 69 contacts the cam 61. Preferably, the piston 63 includes itself identical to the supporting boss 70 with shaft and bearings. It should also be noted, in view of the support boss 70, that the bridge 53b has a corresponding hole to allow passage of the support boss. The bridge 53a has a similar opening, but the portion of the bridge shown in the drawing is in the same plane as the connecting rods 64 and 65. The reverse rotation of the cam 61 relative to the cam 60 is carried out by a differential gear 71 mounted on the outside of the cylinder block . Housing 72 is provided to hold and cover gear components. In fig. 5, housing 72 is shown in cross section, while gear 71 and shaft 58 are not shown in cross section. The gear train 71 includes a sun gear 73 on a shaft 58. The sun gear 73 is in contact with the drive gears 74 and 75, which in turn are in contact with the planet gears 76 and 77. The planet gears 76 and 77 are connected through shafts 78 and 79 to a second set of planetary gears 80 and 81, which are mounted with sun gear 73 on bushing 83. Bushing 83 is coaxial with respect to shaft 58 and the distal end of the bushing is attached to cam 61. Drive gears 74 and 75 are mounted on shafts 84 and 85, the shafts are supported by bearings in a housing 72. A portion of the gear train 71 is shown in FIG. 6. Fig. 6 is an end view of shaft 58 as viewed from the bottom of FIG. 5. In FIG. 6, sun gear 73 is visible near shaft 57. Drive gear 74 is shown in contact with planet gear 76 on shaft 78. The figure also shows a second planet gear 76 on shaft 78. The figure also shows a second planet gear 80 in contact with sun gear 32 on bushing 83. From Fig. 6 it follows that clockwise rotation of, for example, shaft 58 and sun gear 73 has a dynamic effect on counterclockwise rotation of sun gear 82 and sleeve 83 through pinion gear 74 and planetary gears 76 and 80. Therefore, cams 60 and 61 can rotate in the opposite direction. Other design features of the engine shown in FIG. 5 and the operating principle of the motor are the same as the motor shown in FIG. 1 and 2. In particular, the downward thrust of the piston gives the cams a scissor-like action that can cause reverse rotation via differential gearing. It should be emphasized that while in the engine shown in FIG. 5, ordinary gears are used in the differential gear, bevel gear can also be used. Likewise, ordinary gears can be used in the differential gear train shown in FIG. 1 and 2, engines. In the engines exemplified in FIG. 1-3 and 5, the axes of the roller bearings are aligned, which are in contact with the surfaces of the cams with three working projections. To further improve torque characteristics, the roller bearing axles can be offset. An engine with an offset cam which is in contact with bearings is shown schematically in FIG. 7. This figure, which is a view along the central shaft of the engine, shows a cam 86, a counter-rotating cam 87, and a piston 88. The piston 88 includes support bosses 89 and 90 that carry roller bearings 91 and 92, bearings are shown in contact with the working lobes 93 and 99, respectively, of the cams with three working lobes 86 and 87. From FIG. 7 it follows that the axes 95 and 96 of the bearings 91 and 92 are offset relative to each other and relative to the piston axis. When the bearings are located at a certain distance from the piston axis, the torque increases by increasing mechanical advantage. A detail of another piston with offset bearings on the underside of the piston is shown in FIG. 8. Piston 97 is shown with bearings 98 and 99 housed in housings 100 and 101 on the underside of the piston. It follows that the axes 102 and 103 of the bearings 98 and 99 are offset, but not to the same extent as the bearings in FIG. 7. It follows that a greater separation of the bearings, as shown in FIG. 7, increases torque. The above specific embodiments of the invention relate to two-stroke engines, it should be noted that general principles refer to two- and four-stroke engines. It is noted below that many changes and modifications can be made to the engines as shown in the above examples without departing from the scope and scope of the invention.

All diagrams open in full size on click.

ONCOMING TRAFFIC

Peculiarity two-stroke diesel Professor Peter Hofbauer, who devoted 20 years of his life to working at the Volkswagen concern, is two pistons in one cylinder moving towards each other. And the name confirms this: Opposed Piston Opposed Cylinder (OPOC) - opposing pistons, opposing cylinders.

A similar scheme was used in aviation and tank building back in the middle of the last century, for example, on the German Junkers or the Soviet T-64 tank. The fact is that in a traditional two-stroke engine, both windows for gas exchange are blocked by one piston, and in engines with opposing pistons, an inlet window is located in the stroke zone of one piston, and an exhaust window in the stroke zone of the second. This design allows you to open the exhaust window earlier and thereby better clean the combustion chamber from exhaust gases. And close it in advance to save some working mixture, which in a two-stroke engine is usually discharged into the exhaust pipe.

What is the highlight of the professor’s design? In the central (between the cylinders) location of the crankshaft, serving all the pistons at once. This decision led to a rather intricate connecting rod design. There are a pair of them on each crankshaft journal, and the outer pistons have a pair of connecting rods located on both sides of the cylinder. This scheme made it possible to get by with one crankshaft (previous engines had two of them, located at the edges of the engine) and make a compact, lightweight unit. In four-stroke engines, air circulation in the cylinder is ensured by the piston itself, in an OPOC engine - turbocharging. For better efficiency, an electric motor helps to quickly accelerate the turbine, which in certain modes becomes a generator and recovers energy.

The prototype, made for the army without regard to environmental standards, with a mass of 134 kg develops 325 hp. A civilian version has also been prepared - with about a hundred less power. According to the creator, depending on the version, the OROS engine is 30–50% lighter than other diesel engines of comparable power and two to four times more compact. Even in width (this is the most impressive dimensional measurement) OROS is only twice as large as one of the most compact automobile units in the world - two-cylinder Fiat Twinair.

The OPOC engine is an example of modular design: two-cylinder blocks can be assembled into multi-cylinder units by connecting them electromagnetic couplings. When full power not required; to save fuel, one or more modules can be turned off. Unlike conventional engines with switchable cylinders, where the crankshaft moves even the “resting” pistons, mechanical losses can be avoided. I wonder how things are going with fuel efficiency and harmful emissions? The developer prefers to avoid this issue in silence. It’s clear that the positions of two-stroke bikes are traditionally weak here.

SEPARATE MEALS

Another example of moving away from traditional dogma. Carmelo Scuderi encroached on the sacred rule of four-stroke engines: the entire working process must take place strictly in one cylinder. The inventor divided the cycle between two cylinders: one is responsible for the intake of the mixture and its compression, the second for the power stroke and exhaust. At the same time, the traditional four-stroke engine, called a split cycle engine (SCC - Split Cycle Combustion), runs in just one revolution of the crankshaft, that is, twice as fast.

This is how this motor works. In the first cylinder, the piston compresses the air and supplies it to the connecting channel. The valve opens, the injector injects fuel, and the mixture rushes under pressure into the second cylinder. Combustion in it begins when the piston moves downward, unlike the Otto engine, where the mixture is ignited a little earlier than the piston reaches top dead center. Thus, the burning mixture does not interfere with the piston moving towards it in the initial stage of combustion, but, on the contrary, pushes it. The creator of the engine promises a specific power of 135 hp. per liter of working volume. Moreover, with a significant reduction in harmful emissions due to more efficient combustion of the mixture - for example, with a reduction in NOx output by 80% compared to the same indicator for traditional internal combustion engine. At the same time, they claim that SCC is 25% more economical than naturally aspirated engines of equal power. However, an extra cylinder means additional mass, increased dimensions, and increased friction losses. I can’t believe it... Especially if we take as an example the new generation of supercharged engines made under the motto of downsizing.

By the way, an original recovery and supercharging scheme “in one bottle” called Air-Hybrid was invented for this engine. During engine braking, the stroke cylinder is switched off (the valves are closed), and the compression cylinder fills a special reservoir with compressed air. During acceleration, the opposite happens: the compression cylinder does not work, and stored air is pumped into the working one - a kind of supercharging. Actually, with this scheme, full pneumatic mode is not excluded, when the air pushes the pistons alone.

POWER FROM AIR

Professor Lino Guzzella also used the idea of ​​accumulation compressed air in a separate tank: one of the valves opens the path from the cylinder to the combustion chamber. Otherwise it's conventional engine with turbocharging. The prototype was built on the basis of a 0.75-liter engine, offering it as a replacement for... a 2-liter naturally aspirated engine.

To evaluate the effectiveness of his creation, the developer prefers to compare it with hybrid power units. Moreover, with similar fuel savings (about 33%), Guzzella’s design increases the cost of the engine by only 20% - a complex gas-electric installation costs almost ten times more. However, in the test sample, fuel is saved not so much due to supercharging from the cylinder, but due to the small displacement of the engine itself. But compressed air still has prospects in the operation of a conventional internal combustion engine: it can be used to start the engine in the “start-stop” mode or to drive the car at low speeds.

THE BALL IS SPINING, SPINING...

Among the unusual ICE motor Herbert Hüttlin has the most remarkable design: traditional pistons and combustion chambers are placed inside a ball. The pistons move in several directions. Firstly, towards each other, forming combustion chambers between them. In addition, they are connected in pairs into blocks, mounted on a single axis and rotating along a tricky trajectory specified by a ring-shaped washer. The piston block housing is combined with a gear that transmits torque to the output shaft.

Due to the rigid connection between the blocks, when one combustion chamber is filled with the mixture, exhaust gases are simultaneously released into the other. Thus, for turning the piston blocks by 180 degrees, a 4-stroke cycle occurs, and for a full revolution, two working cycles occur.

First demonstration of a spherical engine at Geneva Motor Show attracted everyone's attention. The concept is certainly interesting - you can watch the work of a 3D model for hours, trying to figure out how this or that system works. However, a beautiful idea must be followed by embodiment in metal. And the developer has not yet said a word about even the approximate values ​​of the main indicators of the unit - power, efficiency, environmental friendliness. And, most importantly, about manufacturability and reliability.

FASHION THEME

The rotary vane engine was invented a little less than a century ago. And, probably, they would not have remembered it for a long time if the ambitious project of a Russian people's car had not appeared. Under the hood of the “e-mobile,” although not immediately, a rotary-blade engine should appear, and even paired with an electric motor.

Briefly about its structure. The axis contains two rotors with a pair of blades on each, forming combustion chambers of variable size. The rotors rotate in the same direction, but with at different speeds- one catches up with the other, the mixture between the blades compresses, a spark jumps. The second one begins to move in a circle in order to “push” the neighbor on the next circle. Look at the figure: in the lower right quarter there is intake, in the upper right quarter there is compression, then counterclockwise there is a stroke and exhaust. The mixture is ignited at the top point of the circle. Thus, during one rotation of the rotor there are four power strokes.

The obvious advantages of the design are compactness, lightness and good efficiency. However, there are also problems. The main one is the precise synchronization of the operation of the two rotors. This task is not easy, and the solution must be inexpensive, otherwise the “e-mobile” will never become popular.

It is not an exaggeration to say that most self-propelled devices today are equipped with internal combustion engines of various designs, using different operating concepts. In any case, if we talk about road transport. In this article we will look at the internal combustion engine in more detail. What it is, how this unit works, what its pros and cons are, you will find out by reading it.

Operating principle of internal combustion engines

The main principle of operation of an internal combustion engine is based on the fact that fuel (solid, liquid or gaseous) burns in a specially allocated working volume inside the unit itself, converting thermal energy into mechanical energy.

The working mixture entering the cylinders of such an engine is compressed. After its ignition using special devices, a overpressure gases that force the cylinder pistons to return to initial position. This creates a constant work cycle that converts kinetic energy into torque using special mechanisms.

To date internal combustion engine device can have three main types:

• often called lung;
• four-stroke power unit, allowing to achieve higher power and efficiency values;
• with increased power characteristics.

In addition, there are other modifications of the basic circuits that make it possible to improve certain properties of power plants of this type.

Advantages of internal combustion engines

Unlike power units, providing for the presence of external chambers, the internal combustion engine has significant advantages. The main ones are:

• much more compact dimensions;
• more high performance power;
• optimal efficiency values.

It should be noted, speaking about the internal combustion engine, that this is a device that in the vast majority of cases allows the use of various types of fuel. It could be gasoline diesel fuel, natural or kerosene and even ordinary wood.

Such universalism brought this engine concept well-deserved popularity, widespread distribution and truly world leadership.

Brief historical excursion

It is generally accepted that the internal combustion engine dates back to the creation of a piston unit by the Frenchman de Rivas in 1807, which used hydrogen in a gaseous aggregate state as fuel. And although since then the internal combustion engine device has undergone significant changes and modifications, the basic ideas of this invention continue to be used today.

The first four-stroke internal combustion engine was released in 1876 in Germany. In the mid-80s of the 19th century, a carburetor was developed in Russia, which made it possible to dose the supply of gasoline to the engine cylinders.

And at the very end of the century before last, the famous German engineer proposed the idea of ​​​​igniting a combustible mixture under pressure, which significantly increased power ICE characteristics and the efficiency indicators of units of this type, which previously left much to be desired. Since then, the development of internal combustion engines has proceeded mainly along the path of improvement, modernization and the introduction of various improvements.

Main types and types of internal combustion engines

Nevertheless, the more than 100-year history of units of this type has made it possible to develop several main types of power plants with internal combustion of fuel. They differ from each other not only in the composition of the working mixture used, but also in design features.

Gasoline engines

As the name implies, units in this group use various types of gasoline as fuel.

In turn, such power plants are usually divided into two large groups:

• Carburetor. In such devices, the fuel mixture is enriched with air masses in a special device (carburetor) before entering the cylinders. After which it is ignited using an electric spark. Among the most prominent representatives of this type are VAZ models, the internal combustion engine of which for a very long time was exclusively of the carburetor type.
• Injection. This is a more complex system in which fuel is injected into the cylinders through a special manifold and injectors. It can occur either mechanically or through a special electronic device. Common Rail direct injection systems are considered the most productive. Installed on almost all modern cars.

Injection gasoline engines is generally considered to be more economical and provide more high efficiency. However, the cost of such units is much higher, and maintenance and operation are much more difficult.

Diesel engines

At the dawn of the existence of units of this type, one could very often hear a joke about the internal combustion engine, that this is a device that eats gasoline like a horse, but moves much slower. With the invention of the diesel engine, this joke partially lost its relevance. Mainly because diesel is able to run on fuel much more Low quality. This means it will be much cheaper than gasoline.

The main fundamental difference between internal combustion is the absence of forced ignition of the fuel mixture. Diesel fuel is injected into the cylinders using special nozzles, and individual drops of fuel are ignited due to the pressure of the piston. Along with its advantages, the diesel engine also has a number of disadvantages. Among them are the following:

• much less power compared to gasoline power plants;
• large dimensions and weight characteristics;
• difficulties with starting under extreme weather and climatic conditions;
• insufficient torque and a tendency to unjustified power losses, especially at relatively high speeds.

Besides, engine repair diesel type, as a rule, is much more complex and expensive than adjusting or restoring the functionality of a gasoline unit.

Gas engines

Despite the cheapness of natural gas used as fuel, the design of internal combustion engines running on gas is disproportionately more complex, which leads to a significant increase in the cost of the unit as a whole, its installation and operation in particular.

On power plants similar type liquefied or natural gas enters the cylinders through a system of special gearboxes, manifolds and injectors. Ignition of the fuel mixture occurs in the same way as in carburetor gasoline units - with the help of an electric spark emanating from the spark plug.

Combined types of internal combustion engines

Few people know about combined ICE systems. What is it and where is it used?

We are, of course, not talking about modern hybrid cars, capable of running on both fuel and an electric motor. Combined engines internal combustion is usually called such units that combine elements various principles fuel systems. Most a prominent representative families of such engines are gas-diesel units. In them, the fuel mixture enters the internal combustion engine block in almost the same way as in gas units. But the fuel is ignited not with the help of an electric discharge from a candle, but with an ignition portion of diesel fuel, as happens in a conventional diesel engine.

Maintenance and repair of internal combustion engines

Despite the fairly wide variety of modifications, all internal combustion engines have similar fundamental designs and circuits. However, in order to carry out high-quality maintenance and repair of an internal combustion engine, it is necessary to thoroughly know its structure, understand the principles of operation and be able to identify problems. To do this, of course, it is necessary to carefully study the design of internal combustion engines of various types, to understand the purpose of certain parts, assemblies, mechanisms and systems. This is not an easy task, but very exciting! And most importantly, it is necessary.

Especially for inquisitive minds who want to independently comprehend all the mysteries and secrets of almost any vehicle, an approximate fundamental internal combustion engine diagram is shown in the photo above.

So, we found out what this power unit is.

The utility model relates to the field of engine building. A design has been proposed for an engine operating on a two-stroke cycle with supercharging and a combined gas exchange scheme, in which during the first phase the cylinder is purged and filled with one air according to the usual crank-chamber gas exchange scheme, during the second phase the cylinder is pressurized, over-enriched in the carburetor, compressed in the compressor fuel mixture through inlet ports in the cylinder having intake phases exceeding exhaust phases. To prevent combustion products from entering the cylinder into the receiver during the expansion stroke, the windows are closed with a special ring that acts as a spool, controlled by a cam or eccentric on the journal of the crankshaft, or any other shaft rotating synchronously with it.

The engine is made with two opposing cylinders mounted on one common crankcase, and three crankshafts, of which one has two cranks located at an angle of 180° relative to each other. The cylinders contain pistons with two piston pins connected by connecting rods to crankshaft cranks, symmetrically located relative to the cylinder axis. The pistons consist of a head with compression rings and a double-sided skirt. The lower part of the skirt is made in the form of an apron covering the exhaust ports when the piston is at top dead center (TDC). When the piston is at bottom dead center (BDC), the apron is located in the area occupied by the crankshafts. The upper part of the skirt, when the piston is at TDC, enters the annular space located around the combustion chamber. Each engine cylinder is equipped with an individual compressor, the pistons of which are connected by means of a rod to the engine pistons of the opposing cylinders.

The economic effect of reducing fuel consumption at a gasoline cost of 35 rubles/l. will be about 7 rubles/kWh, i.e. a 20 kW engine will save about 70,000 rubles or 2,000 liters of gasoline over a service life of 500 hours.

Considering the presence of high energy-economic indicators in terms of power, weight and dimensions, ensured by the use of a 2-stroke cycle, supercharging, a 25-30% reduction in fuel consumption, while maintaining the engine life within the same limits of 5,001,000 operating hours by reducing the load on the connecting rod bearings of the crankshafts when doubling, the proposed engine design in a 2- or 4-cylinder version with a power of up to 2060 kW can find application in power plants of aircraft, planing small vessels with engines in the form of air or propellers, portable motorized products used by the population, in the departments of the Ministry of Emergency Situations, the Army and the Navy, as well as in other installations where low specific weight and dimensions are required.

The proposed utility model relates to the field of engine building, in particular, to two-stroke carburetor internal combustion engines (ICE), which transmit forces from gas pressure to the piston by a crank of crankshafts symmetrically located relative to the cylinder axis and rotating in opposite directions.

These engines have a number of advantages, the main ones of which are the possibility of balancing the inertia forces of reciprocating moving masses due to the counterweights of the crankshafts, the absence of forces causing increased friction of the piston on the cylinder walls, the absence of reactive torque, high specific energy-economic parameters in terms of power and weight and dimensions, reduced loads on the connecting rod bearings of the crankshaft, which mainly limit the engine life.

A two-stroke carburetor engine with a crank-chamber gas exchange circuit is known, containing a cylinder, a piston with two piston pins placed in it, two crankshafts symmetrically located relative to the cylinder axis, each of them connected by a connecting rod to one of the piston pins. ( Two stroke engine internal combustion. Patent RU 116906 U1. Bednyagin L.V., Lebedinskaya O.L. Bull. 16. 2012).

The engine is distinguished in that the piston is made in the form of a head with a double-sided skirt, the lower part of the skirt, when the piston is at bottom dead center (BDC), is located in the area occupied by the crankshafts, the upper part of the skirt, when the piston is at top dead center (TDC), partially enters the annular space located around the combustion chamber, with the intake and exhaust ports located at two levels: the inlet ports are located above the piston head when it is at BDC, the exhaust ports are located above the upper edge of the skirt.

The engine design is known, made according to the scheme one cylinder - two crankshafts, providing increased power through the use of supercharging (Two-stroke internal combustion engine with supercharging. Application 2012132748/06 (051906). Bednyagin L.V., Lebedinskaya O.L. Received FIPS 07/31/12), where a compressor (supercharger) cylinder is placed coaxially with the engine cylinder, the piston of which is connected to the engine piston by means of a rod, the external discharge cavity of the pump is connected by channels to the crankcase space, from which its internal cavity is isolated using a sealing sleeve placed on the rod and fixed between the two halves of the crankcase. The external cavity of the compressor provides additional supply of the fuel mixture to the engine crankcase. To ensure additional charging, the engine cylinder is equipped with additional inlet (purge) windows located above the main ones, with intake phases exceeding exhaust phases, while check plate valves are placed between them in the plane of the cylinder and crankcase connector, preventing burnt fuel products from entering the cylinder into the crankcase when the pressure in it exceeds the pressure inside the crankcase. The specified engine is a prototype of the proposed PM design.

All carburetor two-stroke engines with a crank-chamber gas exchange scheme (purging and filling the cylinder with fresh fuel mixture), including the prototype, have a common significant disadvantage - increased consumption fuel associated with the loss of part of the fuel during purging, carried out directly by the fuel mixture.

Work to eliminate this drawback is practically carried out in one direction - purging with clean air and using direct fuel injection into the cylinder. The main difficulty holding back the introduction of direct fuel injection systems on two-stroke engines is high price fuel supply equipment, which on small engines or engines that operate occasionally (for example, a fire engine pump), at current prices, does not pay for itself over the entire period of their operation.

The second reason is the problem of ensuring operability fuel equipment and the quality of mixture formation due to the need to double the frequency of fuel supply to the cylinder when using a two-stroke cycle and further increase it, taking into account the growing trends in speed modes of internal combustion engines, and especially small ones operating on a two-stroke cycle.

However, one should not expect that the creation of new, more advanced equipment for “two-stroke” engines will increase the economic feasibility of its use on the above engines, because it will be even more expensive.

The technical result of the proposed engine design is a reduction specific consumption fuel to a value of 380410 g/kWh, which is 2530% lower than that of commercially produced two-stroke carburetor engines with a crank-chamber gas exchange scheme (Prospects two-stroke internal combustion engines on general aviation aircraft. V. Novoseltsev (http://www.aviajournal.com/arhiv/2004/06/02.html), while maintaining high energy and other indicators that ensure its competitiveness.

To achieve this result, a set of design solutions was used:

1. A two-stroke internal combustion engine is used, with two opposing cylinders installed on one common crankcase, which ensures the transmission of forces from gas pressure to the crankshaft cranks, symmetrically located relative to the cylinder axis. The use of this scheme allows you to use their advantages indicated above and rationally place piston compressors with their drive for supercharging.

2. To implement a two-stroke cycle of engine operation with crank-chamber purge and improve its parameters, the volume of the crank chamber is reduced, for which a piston in the form of a head with a double-sided skirt is used, ensuring the placement of the lower skirt in the crankshaft area, and the upper one in the annular area, located around the combustion chamber.

3. The engine cylinders are equipped with three sets of windows located at different levels: purge windows above the bottom of the piston head, when it is at BDC, exhaust windows above the upper edge of the piston skirt. At the same time, the “time-cross-section” of the windows increases, the phenomenon of “short circuit” - direct emission of the (fuel) mixture from the exhaust windows into the exhaust windows is eliminated, the level of residual gases decreases, the entire perimeter of the exhaust windows becomes available for the outflow of exhaust gases and is reduced by almost half their path; which helps maintain gas exchange parameters with increasing speed limit engine. It should also be noted that the device that ensures the asymmetry of the valve timing is located in a thermally low-load zone, which distinguishes it favorably from similar devices operating in the exhaust gas channels of sports car engines.

4. Inlet windows located above the purge windows, with intake phases exceeding exhaust phases, to prevent combustion products from entering the cylinder into the receiver 10 during the expansion stroke, unlike the prototype, are closed by ring 11, which acts as a spool controlled by a cam or eccentric on the trunnion crankshaft (or any other shaft rotating synchronously with it).

5. To save fuel, a design has been proposed that ensures the use of a combined gas exchange scheme by first purging the cylinders with clean air from the crank chamber, then recharging them (supercharging) with a re-enriched fuel mixture through the use of separate compressors for each cylinder.

6. The inlet tract of the fuel mixture, containing the carburetor(s), check plate valves (VVVs), suction and discharge cavities of the compressor, receiver and inlet windows of the cylinder, is separated from the crankcase space, which is equipped with its own individual air intake system used for purging cylinders

7. Each cylinder of the engine and compressor is made in one block, while the synchronous movement of their pistons in opposite directions is achieved by connecting the compressor piston with the engine piston of the opposite cylinder.

8. The necessary directions of rotation of the crankshafts and purge air flows are ensured by the use of three crankshafts, one of which is made with two cranks located at an angle of 180° to each other, which ensures the movement of the pistons in opposite directions.

9. To reduce the dimensions of the engine, the lower piston skirt is made in the form of a one-sided “apron”, which provides coverage of the exhaust ports when it is positioned at TDC.

10. To maintain pressure in the receiver when the engine piston moves in the TDC direction, the compressor discharge cavity is separated from it by a check plate valve.

Design solutions that have features that characterize the novelty of the proposed model:

1. Push-pull design carburetor engine in an opposed design with two opposing cylinders mounted on one crankcase and three crankshafts, ensuring the transmission of forces from the piston to the cranks of the crankshafts, symmetrically located relative to the cylinder axis (items 1 and 2; hereinafter, see above);

2. A combined gas exchange scheme, in which during the first phase the cylinder is purged and filled with air alone, and in the second phase the cylinder is pressurized with an over-enriched fuel mixture (see above, point 5).

3. A separate inlet tract of the fuel mixture, including the cylinder inlet windows, separated from the crankcase space (item 6).

4. Drive of the compressor pistons due to their connection with the engine pistons of opposite cylinders (item 7), ensuring the movement of the engine and compressor pistons in opposite directions.

5. A piston with a lower skirt made in the form of a one-sided “apron” (item 9).

6. A device that ensures asymmetrical valve timing (clause 4).

7. Placement of the engine and compressor cylinders in one block (item 7).

The layout of the proposed engine model is shown in the drawings: Fig. 1 shows a horizontal section along the cylinder axes. Figure 2 - vertical section A-A along the axes of the crankshafts, which also shows a gearbox that provides kinematic connection crankshafts between each other and the possibility of creating a four-cylinder modification by installing a similar two-cylinder engine on the lower side of the gearbox is visible.

The cylinders 1 contain pistons 2 placed in them with two piston pins, each of which is connected by a connecting rod 3 to the cranks of the crankshafts 4, symmetrically located relative to the axis of the cylinders. The piston consists of a head with compression rings and a double-sided skirt. The lower part of the skirt is made in the form of a one-sided apron covering the exhaust ports when the piston is at TDC. When the piston is at BDC, the apron is located in the area occupied by the crankshafts. The upper part of the skirt, when the piston is in the (TDC) position, enters the annular space 5 located around the combustion chamber, which is connected to it by tangential channels. Each engine cylinder is equipped with an individual compressor 6, made in the same block, the pistons 7 of which are connected by means of rods 8 to the engine pistons of opposite cylinders 2.

The engine cylinders are equipped with inlet ports 9 located above the purge ports, with intake phases exceeding exhaust phases. To prevent combustion products from entering the cylinder into the receiver 10 during the expansion stroke, the windows are closed with a ring 11, which acts as a spool, controlled by a cam or eccentric on the journal of the crankshaft 4 (or any other shaft rotating synchronously with it). The control mechanism is shown in Fig.3.

The discharge cavity of the compressor is connected by channels not to the crankcase space, but to the receiver, from where the fuel mixture, previously over-enriched in the carburetor, enters the cylinder through the intake windows, where, mixing with the air coming from the crankcase during purging and residual gases, it forms a working fuel mixture. Between the suction cavity of the compressor, isolated from the crankcase space, and the carburetor, check plate valves are installed (not shown in the figure), ensuring the flow of the fuel mixture into the compressor. To supply air used for purging, similar valves are installed on the crankcase on the cylinder side of the engine. Valves 12 installed at the mixture outlet from the compressor are designed to maintain pressure in the receiver when the engine piston moves in the TDC direction.

The adopted layout with three crankshafts ensures a rational arrangement of the engine and compressor cylinders to organize the flow of the fuel mixture from the compressor to the engine, reduces the resistance to the flow of scavenging air when it is bypassed from the crankcase to the cylinder, increases manufacturability due to the manufacture of cylinders in one block, and allows for low cost create a four-cylinder modification, or a gearbox with shafts rotating in opposite directions.

Thus, a reduction in specific fuel consumption is achieved by using instead of air-fuel mixture only one air into which fuel for the work process is supplied, mainly after completion of the purging process in the form of a re-enriched fuel mixture from the compressor, carried out by supercharging, through the inlet windows, when the outlet windows are closed by the upper edge of the piston skirt.

Since the labor intensity of manufacturing an engine with the proposed combined gas exchange scheme compared to the labor intensity of manufacturing a similar engine made with crank-chamber purging of the cylinders with a fuel-air mixture will practically not change, the economic effect of its use will be determined only by the reduction in fuel losses during gas exchange, which when purging with the fuel mixture makes up about 35% of its total consumption (G.R. Ricardo. High-speed internal combustion engines. State scientific and technical publishing house of mechanical engineering literature. M. 1960. (p. 180); A.E. Yushin . Direct fuel injection system in two-stroke internal combustion engines. In the collection "Improving the power, economic and environmental indicators of internal combustion engines", VlGU, Vladimir, 1997., (p. 215).

The economic effect of using the proposed engine design with combined system gas exchange, ensuring a reduction in specific fuel consumption compared to the previous crank-chamber scheme using a fuel mixture for purging, at a gasoline cost of 35 rubles/l. will be about 7 rubles/kWh, i.e. a 20 kW engine will save about 70,000 rubles or 2,000 liters of gasoline over a service life of 500 hours. In the calculations, it was assumed that fuel losses during purging will decrease by 80%, because possibility of the fuel mixture getting into exhaust system reduced only in the duration of simultaneous opening of the intake and exhaust windows from 125° crankshaft rotation to 15°. Placement of inlet and outlet windows on different levels gives reason to believe that fuel losses will be reduced even more or stopped altogether.

Considering the presence of high energy-economic indicators ensured by the use of a two-stroke cycle, supercharging, a 25-30% reduction in fuel consumption, while maintaining the engine life within the same limits of 5,001,000 operating hours by reducing the load on the connecting rod bearings of the crankshafts when doubling them, the proposed engine design in 2 or 4-cylinder version with a power of up to 2060 kW can find application in power plants of aircraft, planing small vessels with propulsion in the form of air or propellers, portable motor products used by the population, in the departments of the Ministry of Emergency Situations, the Army and Navy, as well as in others installations where small specific gravity and dimensions are required.

1. A two-stroke internal combustion engine with supercharging and a combined gas exchange scheme, transmitting force from gas pressure on the piston simultaneously to two crankshafts symmetrically located relative to the cylinder axis, containing built-in compressors coaxially with the cylinder axis, the pistons of which are connected by means of a rod to the engine pistons, cylinders equipped with inlet windows located above the purge ports, with intake phases exceeding exhaust phases, with one common crankcase, characterized in that it is made in a two-cylinder opposed design, with oppositely moving pistons, with three crankshafts, one of which has two cranks, contains a separate inlet tract of the fuel mixture, isolated from the crank chamber, including a carburetor, check plate valves, a compressor with suction and discharge cavities and a receiver connected to the inlet windows of the cylinder, through which the over-enriched fuel mixture enters the engine cylinders, while the compressor pistons are kinematically connected to pistons of opposing engine cylinders.