SK8962003A3 - Four-stroke engine with opposed pistons - Google Patents

Abstract

Engine consists of a cylinder (1) with opposed a first and second piston (2.1, 2.2) with a first and second piston rod (3.1, 3.2) and with a first and second crankshaft (4.1, 4.2). The first crankshaft (4.1) has a first satellite gear (5.1), which fit into fixed a first gear rim, or a tooth gear (6.1) with a internal toothing and the second crankshaft (4.2) has a second satellite gear (5.2), which fit into fixed a second gear rim or a tooth gear (6.2) with a internal toothing. The first piston rod (3.1) of the first piston (2.1) is coupled by a second end with offset axes seating a first auxiliary shaft (7.1) on the first satellite gear (5.1) and the second piston (3.2) rod of the second piston (2.2) is coupled by a second end with offset axes seating a second auxiliary shaft (7.2) on the second satellite gear (5.2). The crankshaft (4.1, 4.2) has a tooth gear (8.1, 8.2). The tooth gear (8.1, 8.2), that is fixed on the crankshaft (4.1, 4.2) fitted into a reducer (12) with a internal or external toothing. The cylinder (1) in a first part has an intake automatic valve (9) and a exhaust automatic valve (10), and in a second part has an petrol or diesel unit (11).

Description

Technical field

The invention relates to a four-stroke engine with counter-pistons in a modification of a spark-ignition or compression-ignition engine, preferably provided with a reducer. Reducer motors are preferably mounted in helicopters. The invention falls within the field of mechanical engineering in terms of production and, in terms of use, falls within the field of aircraft technology in particular.

BACKGROUND OF THE INVENTION

Nowadays, jet engines are used to drive helicopters where the output shaft speed is about 50000 rpm. However, such high speeds are unacceptable for the rotor blades of the helicopter drive. Therefore, in the helicopter power unit downstream of the jet engine is a reducer, which reduces the speed to 500 rpm. Speed reducers with a reduction ratio of 100 are of massive construction and have a high weight, which is a significant disadvantage. In addition, jet engines have a high fuel consumption.

Multi-cylinder internal combustion engines with the opposite movement of two pistons in one common cylinder are also known in aircraft technology. These engines are always in two-stroke modifications. From a constructional point of view, these engines are characterized by an arrangement where two crankshafts are used on both ends of the cylinders. A typical such engine is the six-cylinder two-stroke in-line diesel engine Jumo 205. The disadvantage of this engine is its large volume and weight. This engine is not usable to drive helicopters.

For the helicopter drive there are limited possibilities in terms of a suitable drive for the rotor blade drive. Therefore, there has been a demand to create a powerplant for helicopters that would ensure a minimum pumping volume of the powerplant at a minimum weight. In doing so, it should be a drive unit with maximum fuel savings, which tends to be four-stroke engines with the simplest design. As a result of this effort, a four-stroke engine with counter-rotating pistons, in particular with a reducer, in a modification of the spark ignition or compression ignition engine of the present invention is described.

SUMMARY OF THE INVENTION

The above drawbacks are overcome by a four-stroke engine with counter-piston pistons in a modification of the spark ignition or compression ignition engine of the present invention, which is based on at least one cylinder with two counter-rotating first and second pistons with first and second connecting rods and first and second crankshaft. The first crankshaft is provided with a first satellite gear geared to a fixed anchored first ring or internally toothed gear. The second crankshaft is provided with a second satellite sprocket engaging a fixed anchored second rim or internally toothed gear. The first connecting rod of the first piston is coupled to the second end with an eccentric bearing of the first auxiliary shaft on the first satellite gear. The second connecting rod of the second piston is coupled with the second end with an eccentric bearing of the second auxiliary shaft on the second satellite gear. Each crankshaft is equipped with a toothed drive or transmission wheel. The cylinder is provided with at least one intake valve and at least one exhaust valve in one part of its length. In the second part of its length, the cylinder is equipped with a positive-ignition or compression-ignition device.

For the functionality of the engine, it is essential that the transmission ratio between the ring gear or the internal gear and the satellite gear is 3: 1 or 3: 2.

From the point of view of the possible utility parameters of the engine, it is advantageous if the engine is arranged in a configuration where it consists of an even number of at least four cylinders arranged in an N-angle where the N - even number. The configuration would be such that one first eccentric bearing of the first auxiliary shaft on the first satellite gear is fitted with the first connecting rod of the first piston of the N th cylinder and the second connecting rod of the second piston of one adjacent cylinder. Also, a second connecting rod of the second piston of the N-th cylinder and a first connecting rod of the first piston of the second adjacent cylinder are mounted by one eccentric second auxiliary shaft mounted on the second satellite gear. In this case, each gear transmission fixedly attached to the crankshaft fits into a gear reducer with internal or external toothing.

Another essential feature of a four-stroke counter-piston engine in a modification of a spark ignition or compression ignition engine according to the present invention is that the first rims or the internal gear teeth are rigidly connected to the second rims or the internal gear teeth.

From a practical point of view, it is advantageous if the four-stroke engine with counter-rotating pistons in the modification of the spark-ignition or compression-ignition engine according to the invention comprises a reducer with internal or external toothing whose output axis is intended to drive helicopter blades. The internal gearing of the reducer appears to be more advantageous because more teeth are engaged between the gear transmission gear and the reducer itself.

The advantages of a four-stroke engine with counter-piston pistons in the modification of the spark-ignition or compression-ignition engine according to the invention are evident from its external effects. In particular, the effect of the engine according to the invention is that the speed of the reciprocating internal combustion engine is substantially lower than that of the turbojet engine, so that the required 500 rpm can be achieved in a single transmission. The transmission is realized by the gear ring of the reducer and the gear transmission and is controlled by the size of the gear transmission diameter. The transmission can also be changed by replacing the reducer realized by the central gearwheel, which is thus engaged from the inside of the gearwheels.

In terms of construction, the engine is ideal for fitting in a helicopter because it is a substantially flat disc construction due to the disposition of its cylinders preferably in a 6-angle such that torque can be removed from the center of the assembly. By using reciprocating internal combustion engines, the helicopter drive is much less noisy than a jet engine, and fuel consumption is considerably less since it is a four-stroke engine. The advantage of this engine arrangement is also advantageous in that it can be implemented in the diesel engine version or in the petrol engine version.

BRIEF DESCRIPTION OF THE DRAWINGS

A four-stroke engine with counter-pistons in a modification of a spark ignition or compression ignition engine according to the invention will be explained in more detail in the specific embodiments shown in the drawings, wherein FIG. 1 shows, in front view, the kinematic arrangement of one cylinder with two pistons and two crank mechanisms. Fig. 2 shows a side view of the kinematic arrangement of one crank mechanism. In FIG. 3 shows the gear ratio between the ring gear and the satellite gear. In FIG. 4.1 and 4.2 show, in six phases, the operation of a four-stroke engine with counter-rotating pistons. In FIG. 5 shows an arrangement of a six-cylinder engine with cranks and a reducer. In FIG. 6 shows the force load of the engine piston.

EXAMPLES

It is to be understood that individual embodiments of the engine of the invention are presented for illustration and not as limitations of the technical solutions. Those skilled in the art will find or be able to ascertain, using no more than routine experimentation, many equivalents to specific embodiments of the engine design specifically described herein. Such equivalents will also be included within the scope of the following claims.

The dimensioning of such an engine and the appropriate choice of its materials and construction arrangements cannot be a problem for those skilled in the art, and therefore these features have not been solved in detail.

Example 1

In this example of a particular embodiment of the present invention, the basic design of a four-stroke positive-ignition SI engine with a reducer is shown as shown in FIG. 1. The four-stroke engine consists of one cylinder 1 with two opposing pistons 2.1, 2.2. The engine thus comprises two crankshafts 4.1 and 4.2, wherein the first crankshaft 4.1 is arranged in front of the first open face of cylinder 1 and the second crankshaft 4.2 is arranged in front of the second open face of cylinder 1. The central axis of the first crankshaft 4.1 is rotatably mounted in a central axis a fixed anchored first rim or first gear 6.1 with internal toothing. The central axis of the second crankshaft 4.2 is rotatably mounted in the central axis of the second annular gear or the second internally toothed gear 6.2. The central crankshaft axes 4,1 and 4.2 are mounted in bearings. Both crankshafts 4.1, 4.2 are each provided with one gear or transmission wheel 8.1, 8.2. The two gear wheels 8.1, 8.2 are each fixedly attached to their crankshaft 4.1, 4.2 and with their teeth engage in a gear reducer 12 with internal or external toothing as shown in FIG. 2. The bearings of the crankshaft bearings 4 are rigidly connected to each other as they form a static engine frame as shown in FIG. 2. Cylinder 1 and the intake and spark manifold mechanisms (not shown) are also attached to the static engine frame. In each case on the centered axis of the first crankshaft 4.1, the first gearwheel 5.1 is fixed by its toothing to the internal toothing of the first ring gear or the first internally toothed gear 6.1. On the center axis of the second crankshaft 4.2, the second gearwheel 5.2 is attached by its toothing to the internal toothing of the second ring gear or the second internally toothed gear 6.2. The first connecting rod 3.1 of the first piston 2.1 of the cylinder 7 is rotatably mounted on a first auxiliary shaft 7.1, which is eccentrically mounted on the first gear satellite 5.1. The second connecting rod 3.2 of the second piston 2.2 of the cylinder 1 is rotatably mounted on a second auxiliary shaft 7.2, which is eccentrically mounted on the second gearwheel 5.2. For the construction of cylinder 7, it is essential that the spark plug is located in the central part of cylinder 1 and that the intake and exhaust ducts are located separately in the peripheral parts of the cylinder TZ, it is essential that the transmission ratio between the rim or gear 6.1, 6.2 the satellite gear 5.1, 5.2 was 3: 1 as shown in FIG. 3. In a variant embodiment, the transmission ratio may also be 3: 2. The gear ratio of the rim or gear 6.1, 6.2 with internal gear and the satellite gear 5.1, 5.2 ultimately changes the speed of the gear reducer 12.

The function of the four-stroke counter-piston engine constructed in accordance with the present invention is as follows and is evident from the individual bars shown in FIG. 4.1 and 4.2. The triangular trajectories of one selected point from the toothed satellite 5.1 and 5.2 also help to understand the function of the engine, which is shown in fig. 1. Finally, the stroke trajectory h gives an idea of the movements of the two pistons in one cylinder 1. shown in FIG. 5. The selected point from the satellite gear 5 shown in FIG. 1, moving in the direction of the arrow along the trajectory, represents the suction cycle when the pistons 2.1, 2.2 move away from each other at 180 ° to 270 ° crankshaft from the bottom dead center. 4.1, 4.2 as shown in FIG. 5. The suction cycle is also shown in FIG. 4.1b. Trajectory b represents the tact of compression when the pistons

2.1, 2.2 approach each other within a rotation range of 270 ° to 360 ° of crankshaft 4.1, 4.2 as shown in Figs. 5th

The compression cycle is also shown in FIG. 4.1c. Trajectory c is an expansion bar when the pistons 2.1, 2.2 are approached at top dead center within a 0 ° to 90 ° crankshaft rotation range

4.1, 4.2 and gradually move away from each other as shown in FIG. 5. The expansion cycle is also shown in FIG. 4.2d. The start of this cycle is an empty part of the cycle for both pistons, with a constant distance between the pistons but moving together for some time. Trajectory d represents the stroke of the exhaust when the pistons

2.1, 2.2 gradually approach each other up to the dead center in the range of 90 ° to 180 ° crankshaft 4,1, 4,2 as shown in fig. 5. The exhaust cycle is also shown in FIG. 4.1a. In FIG. 4.1 also shows the position of the top dead center HU. In FIG. 6a shows the unfavorable lateral loading of the piston from a conventional crankshaft. Finally, FIG. 6b shows the favorable lateral stress of the piston to the lateral pressure in the structure according to the invention. The lateral stress of the piston according to the invention is less than that of a conventional crank arrangement because it is given by the angle β in the formula F _n - F. tg β.

Example 2

In this example of a particular embodiment of the invention, the application structure of a four-stroke SI engine with a forced feed and a reducer is shown as shown in FIG. 5. This engine assembly consists of six four-stroke single cylinder engines sufficiently described in Example 1. The individual cylinders 1 are arranged in a hexagon. The engine therefore also comprises six crankshafts 4.1 and 4.2 and the mechanisms connected to them. The configuration would be such that one first eccentric bearing of the first auxiliary shaft 7.1 on the first satellite gear 5.1 is fitted with the first connecting rod 3.1 of the first piston 2.1 of the first cylinder 1 and the second connecting rod 3.1 of the second piston 2.2 of one adjacent cylinder 7 in this case the sixth cylinder 1. The same five also between the combinations of the first and second cylinders 7, the second and third cylinders 1, the third and fourth cylinders 7, the fourth and fifth cylinders 7, and finally the fifth and sixth cylinders 1. 8.1, 8.2 are fixedly attached to the respective crankshafts which fit with their teeth into the internal gear reducer 12.

Example 3

In this example of a particular embodiment of the invention, a four-stroke compression engine with forced-action counter-pistons is described. The engine is sufficiently described in Examples 1 and 2. The only difference is in the configuration of the diesel engine, as is clear from the name itself.

In a further improved version, the engine may be provided with a gear reducer 12 realized by a gear that is in contact with the gear wheels 8.1, 8.2 from the inside thereof. For clarity, the ratio of the diameter of the reducer 12 and the transmission wheels is shown

8, 8, 8, it is possible to select the gear ratio of the speed reduction and thus ultimately to select the speed of the rotor blades of the helicopter drive.

Industrial usability

The four-stroke engine with counter-rotating pistons in the modification of the spark-ignition or compression-ignition engine according to the invention finds application in the aircraft industry, especially in helicopter constructions.

Claims (5)

PATENT CLAIMS A four-stroke engine with counter-pistons in a positive-ignition or compression-ignition engine modification, characterized in that it consists of at least one cylinder (1) with two first and second pistons (2.1, 2.2) arranged opposite to each other with first and second connecting rods (3.1, 3.2) and first and second crankshafts (4.1, 4.2) such that the first crankshaft (4.1) is provided with a first satellite gear (5.1) engaging a fixed anchored first ring or internally toothed gear (6.1) and a second crankshaft (4.2) ) is provided with a second satellite gear (5.2) engaging a fixed anchored second rim or internally toothed gear (6.2), the first connecting rod (3.1) of the first piston (2.1) being coupled with a second end with an eccentrically mounted first auxiliary shaft (7.1) on the first satellite gear (5.1) and wherein the second connecting rod (3.2) of the second piston (2.2) is coupled with the eccentric ý a second auxiliary shaft (7.2) mounted on the second satellite gear (5.2), each crankshaft (4.1, 4.2) being equipped with a gear or transmission wheel (8.1, 8.2); wherein each gearwheel (8.1, 8.2) fixedly attached to the crankshaft (4.1, 4.2) fits into an internal or external gear reducer (12); the cylinder (1) is provided with at least one intake valve (9) and at least one exhaust valve (10) in one part of its length; the cylinder (1) is provided with a positive-ignition or compression-ignition device (11) in the second part of its length. A four-stroke engine with counter-pistons in a positive-ignition or compression-ignition engine modification according to claim 1, characterized in that the transmission ratio between the inner ring gear or the gear (6) and the satellite gear (5) is 3: 1 or 3 : 2. A four-stroke engine with counter-pistons in a positive-ignition or compression-ignition engine modification according to claims 1 and 2, characterized in that it consists of an even number of at least four cylinders (1) arranged in an N-angle, where N = even so the eccentric mounted first auxiliary shaft (7.1) on the first satellite gear (5.1) is fitted with a first connecting rod (3.1) of the first piston (2.1) of the N-th cylinder (1) and a second connecting rod (3.2) of the second piston (2.2) of one adjacent cylinder ( 1) and a second connecting rod (7.2) on the second satellite gear (5.2) is fitted with a second connecting rod (3.2) of the second piston (2.2) of the first cylinder (1) and a first connecting rod (3.1) of the first piston (2.1) the second adjacent cylinder (1). A four-stroke engine with counter-piston engines in a positive-ignition or compression-ignition engine modification according to claims 1 to 3, characterized in that the first rims or the internal gear teeth (6.1) are rigidly connected to the second rims or the internal gear teeth (6.2). . A four-stroke engine with counter-piston engines in a spark-ignition or compression-ignition engine modification according to claims 1 to 4, characterized in that the internal or external gear reducer (12) comprises a helicopter blades output axis (13).