WO2006082455A1

WO2006082455A1 - Arrangement for piston machines to influence the force/moment arising during operation on the supports of the cylinder block having a main shaft casing

Info

Publication number: WO2006082455A1
Application number: PCT/HU2006/000011
Authority: WO
Inventors: Geza Halmai
Original assignee: Ricardo Deutschland Gmbh
Priority date: 2005-02-02
Filing date: 2006-01-31
Publication date: 2006-08-10
Also published as: HU0500168D0; EP1904758A1; HUP0500168A2

Abstract

The invention is an arrangement (1) for piston type machines or power machines, for influencing the force/torque arising during operation on the clamping/supporting members (17) of the cylinder block (2) with a main shaft casing, which arrangement (1) has a main shaft (5) running on bearings in the cylinder block (2) with a main shaft casing, and the said main shaft (5) has a first flywheel (21) connected torsionally rigidly to it, and it has at least another second flywheel (22), the first (21) and the second flywheel (22) are linked by a dual shaft engaged drive unit (4) and it has a power output shaft (23). According to our invention the first (21) and the second flywheel (22) has geometrical axes parallel with each other, and they are preferably identical, the drive unit reversing mechanism connecting them is designed as a drive unit (4) with constant momentary ratio transmission, the first flywheel (21) is torsionally rigidly linked to the first shaft (30) of the reversing drive unit (4) with constant momentary ratio transmission, the second flywheel (22) is torsionally rigidly connected to the second shaft (27), the cylinder block (2) with a main shaft casing is torsionally rigidly connected to the gear case (24) of the reversing drive unit (4) with a constant momentary ratio transmission, the power output shaft (23) is linked torsionally rigidly or via a drive unit to the second flywheel, the angular momentum of the first (21) and second flywheel (22) is the same in an absolute sense, in a way that the angular momentum of all the unidirectionally turning members is to be imputed in the angular momentum of the first flywheel, and the angular momentum of the second flywheel includes the angular momentum of all the members rotating in the same direction.

Description

Arrangement for piston machines to influence the force/moment arising during operation on the supports of the cylinder block having a main shaft casing

The invention is an arrangement for piston machines or power machines for influencing the periodically changing force/torque arising during operation on the clamping/supporting members of the cylinder block with a main shaft casing, and for reducing the extent of change, where the word 'operation' has the following meaning: the initial (start-up) revolutions, as well as running with a uniform and varying number of revolutions.

It is a well-known characteristic of power machines and compressors having a crankshaft, a connecting rod running on bearings on the said crankshaft, and a piston linked to the end of the said connecting rod that during operation - if they are suspended flexibly - their crankcases make an oscillating movement or - in the case of a rigid suspension - they exert vibrating forces or torques many times higher than the weight of the engine or power machine on the machine foundation. The vibrating forces and torques can be reduced by balancing. However - partly due to conceptual and partly to practical reasons - this balancing is never perfect.

Literature dealing with compensation (see Hans List/Anton Pischinger: Die Verbrennungskraftmaschine III. Springer Verlag. Wien New York) gives a detailed discussion of the mass forces generated by pistons moving back and forth, their balancing, the extent of (tilting and transversal) torques resulting from the spatial location of the mass forces and the options of compensating these torques. It deals in details with the options of balancing the rotary (crankshaft) and partly turning (connecting rod) parts. It also details comprehensively the inequality of output angular velocity and the methods of reducing the so-called degree of inequality, but it does not deal with the torque generated as a result of a change in the angular momentum of the flywheel (the moment vector in this case is parallel with the main shaft). The train of thoughts is not described, but could be assumed that the output angular velocity only fluctuating by some percent at the most also results in 'a uniform output torque as a result of the always prevailing torsional flexibilities, and therefore again a uniform reaction torque atises on the suspention points of the cylinder block of a piston machine. However, this is not so.

In motorcycles, such a solution is applied for compensating the spinning effect of the crankshaft and the flywheel, in which a substantial mass, e.g. the coupling, the unified generator and the starter motor are turning in an opposite direction with the crankshaft, by means of a gear drive unit. In the case of cardan shaft motorcycles, where the crankshaft is parallel with the longitudinal axis of the vehicle, the gyroscopic moment influences the stability of the vehicle when negotiating a curve, and the masses turning in an opposite direction than the crankshaft serve for improving this stability. Regardless of the fact that the objective of these approaches is different than that of this invention, in principle the accomplishing of this objective' as an additional result could not be ruled out. To this end, however, a special reversing drive unit would be required. The approach closest to this invention is the patent specification WO 03/004845. The object of the invention is a piston engine, which is integrated with an electric machine, preferably for hybrid drive vehicles. The specification describes that the balancing shaft and the electric machine are turning intentionally in an opposite direction to that of the crankshaft, thereby (partially) compensating the reaction torque which is generated cyclically during the combustion of the fuel/air mixture. The specification states that a mass rotating in an opposite direction with a higher revolution than the crankshaft is more effective than a mass turning in an opposite direction with the same number of revolutions. The specification states correctly that the difficulties caused by a cyclical reaction torque are more serious in the case of three-cylinder engines than in a four- cylinder engine, but it is not recognised that a cyclical reaction torque does not arise only as a result of combustion peak pressures, but also due to the . linear alternating movement of the pistons. This patent specification makes reference to the inventor Paul Heron, whose US patent 3,402,707 has already covered the principle of fully balancing (eliminating) the angular momentum, but both documents referred to present a generally applied common gear drive unit for compensating a cyclical reaction torque. Our finding is, however, that it is not suitable for this function, because the angular vibration amplitudes are of a comparable extent with the backlash. '

The objective of this invention is to create an approach for' reducing as much as possible the fluctuation of the torque arising on the supports of the cylinder block casing. The basis of the invention is the recognition that the energy storage role of the flywheel implies inevitably a fluctuation in its revolutions and as a result in its angular momentum, which change in the angular momentum may only be generated inevitably by the torque fluctuations - ultimately at the suspension points of the cylinder block casing. If it is ensured that all the rotating components in the cylinder block casing are in a constrained coupling with each other and that the resulting angular momentum is zero (∑θ_nω_n = 0, where angular speeds of an opposite direction are to be shown with a negative sign), there will be no fluctuation in the angular momentum in spite of the fluctuation in the revolutions, i.e. a fluctuation in reaction torque resulting therefrom does not arise either at the suspension points of the cylinder block. When balancing the whole angular momentum, for example the high torque peak generated by the combustion pressure does not appear on, the suspension points of the cylinder block, because the casing of the drive unit generating an opposite sense of rotation provides exactly the same but opposite direction torque than the one required for accelerating the flywheels. As a result of the rigid link between the cylinder block and the reversing drive unit casing, only the difference between the reaction torque of the cylinder block and the reaction torque of the drive unit generating an opposite sense of rotation appears, i.e. the reaction torque of the uniform output torque. Furthermore, the basis of the invention is the recognition that since the fluctuations in revolutions appear with the frequency or upper harmonics 'of combustion cycles, and the absolute value of fluctuations is low, a suitably accurate and zero-backlash reversing drive unit is required for balancing the angular momentum.

Furthermore, the basis of the invention is the recognition that the backlash in a reversing drive unit made with a backlash can be eliminated by such a pre-tensioning, where the pre-tensioning torque is provided by the output/input torque proper. This effect is generated in case the second flywheel is not located on the 'blind shaft' in parallel with the useful flow of energy, but in series therewith.

Furthermore, the basis of our invention is the recognition that in order to make a zero- backlash reversing drive unit, it could be advantageous when the revolutions of the flywheel turning in the opposite direction are lower than those of the crankshaft (this does not contradict the specification WO 03/004845 mentioned above: if the aim is only to compensate the angular momentum with as low a rotating mass as possible, then an accelerating transmission is to be used actually). The subject of the invention is an arrangement for piston type or power machines for influencing the force/torque arising during operation on the clamping/supporting members of the cylinder block with a main shaft casing, which arrangement has a main shaft running on bearing in the cylinder block with a main shaft casing, a first flywheel linked to this main shaft torsionally rigidly, and it has at least one more second flywheel, the first and second flywheels are coupled by a dual shaft engaged drive unit, and it also has an output shaft. .

According to the invention, the geometrical axes of the first and second flywheels are parallel and preferably identical with each other, and the drive unit coupling them is designed as a reversing, constant momentary ratio transmission, the first flywheel is torsionally rigidly linked to the first shaft of the reversing constant momentary ratio transmission, the second flywheel is coupled torsionally rigidly with its second shaft, the cylinder block with a main shaft casing is linked torsionally rigidly to the casing of the reversing, constant momentary ratio transmission, the power output shaft is engaged to the second flywheel torsionally rigidly or via a drive unit, the angular momentum of the first and second flywheel is identical in the absolute sense in a way that the angular momentum of all the members rotating unidirectionally (in the same direction) with it is to be included in the angular momentum of the first flywheel, and the angular momentum of all the members rotating in the same (identical) direction with it is to be included in the angular momentum of the second flywheel.

The object of the invention furthermore is a piston compressor or internal combustion piston engine, which has a crankcase cylinder block with clamping/supporting members, and in the former it has a crankshaft running oh bearings, with a connecting rod running on bearings thereon and coupled to a piston, it has a first flywheel coupled torsionally rigidly to the crankshaft, the first and second flywheels are coupled by a dual shaft engaged drive unit, and it has an output shaft.

According to the invention, the geometrical axes of the first and second flywheels are parallel and preferably identical with each other, the drive' unit linking them is designed as a reversing constant momentary ratio zero-backlash drive unit, the first flywheel is torsionally rigidly coupled with the first (input) shaft of the reversing constant momentary ratio transmission, the second flywheel is torsionally rigidly coupled to the second shaft of the reversing constant momentary ratio transmission, the cylinder block with a crankcase is coupled torsionally rigidly with the drive unit casing of the reversing constant momentary ratio transmission, the angular momentum of the first and second flywheels is identical in an absolute sense in a way that the angular momentum of all the members rotating unidirectionally (in the same direction) with it is to be included in the angular momentum of the first flywheel, and the angular momentum of all the members rotating in the same direction with it is to be included in the angular momentum of the second flywheel.

In the preferential embodiment of the compressor or motor embodying the invention, the reversing constant momentary ratio transmission is designed as a zero-backlash gear drive unit, preferably as a pseudo epicyclical drive unit, the first sun wheel of which is fixed rigidly to the crankshaft, the outer toothing of which engages the outer toothing of the first pseudo epicyclical gears, which engage the inner toothing of the first gear rim, and the second flywheel is coupled torsionally rigidly to the first gear rim, the stationary shafts of the first pseudo epicyclical gears are secured to the drive unit casing of the gear drive unit secured rigidly to the cylinder block having a crankcase, and preferably on the same shafts second pseudo epicyclical gears are embedded, the toothing of which also engages the teeth of the second gear rim engaging torsionally rigidly the first gear rim, and it also engages the teeth of the second sun wheel, the output shaft is fixed

1 torsionally rigidly to the second sun wheel, ^~ and between the first and second sun wheels, by means of a force and motion transfer coupling a tangential wedging unit is installed, which performs the joint zero-backlashing functions of the reversing constant momentary ratio transmission and the reversing drive uriit. The second gear rim, the second pseudo epicyclical gears and the second sun whebl make up a reversing drive unit.

In a further preferential embodiment of the compressor/engine embodying the invention, the tangential wedging unit arranged between the first and second sun wheels is designed as a recess confined by support surfaces in a Wheel disc , and as a nose with a support surface protruding into the said recess and arranged on the other wheel disc. A pressure spring, hereinafter spanner spring is fitted between the two facing support surfaces, the said spanner spring is preferably designed as' a Belleville spring/Belleville spring column, the largest displacement of which is selected in a way that it is longer than the extent necessary for the joint backlash switching of the teeth of the first and second sun wheels, those of the pseudo epicyclical gears and those of the gear rim. The approach embodying the invention enables the achieving of a drive unit of a comfort degree already used as a standard in vehicles fitted with a piston engine based on a large number of cylinders, for example in cars, but this is accomplished with a piston engine which has a low number of cylinders, e.g. by using a three-cylinder engine instead of six cylinders, or for example a two cylinder engine instead of a four- cylinder one. If the swept volume is the same with a lower number of cylinders, the dimensions of each cylinder are larger, and this makes a, favourable influence on the engine parameters, including the environmental characteristics.

In the arrangement embodying the invention, i.e. in the case of a piston compressor or internal combustion piston engine, we have determined as one of the characteristics of the reversing drive unit coupling the first flywheel and the second flywheel turning in an opposite direction that it is of the constant momentary ratio transmission type. This means the following: the ratio of the angular velocities of the two shafts rotating in opposite directions provides the transmission, which is constant with such a small error even within one turn that it represents an angular ' acceleration fluctuation of approximately one magnitude lower than the angular acceleration fluctuation of the first flywheel. We have determined as one characteristic, of the reversing constant momentary ratio transmission that it is of the zero-baeklash type. This means the following: the constant momentary ratio transmission mentioned above is retained when the sign of the torque acting on any shaft of the drive unit changes, i.e. the drive unit has a zero-backlash even in the vicinity of zero torque. From 'the aspect of the invention, a gear drive unit pre-stressed tangentially and made with a backlash can be considered to be also of the zero-backlash type if the pre-stressing is selected in a way that the changeover of the engaging tooth side does not occur at ariy functional working point of the piston machine. '

It can be proven that the process in time of the reaction tofque arising on the suspension members is independent of the extent of the moment of inertia of the flywheel, and it is far from being smooth. The lower the number of cylinders, and the higher the combustion peak pressure and the revolutions, the higher is the imbalance. With high revolutions, the engine weight per one output unit can be reduced; a high combustion peak pressure is one way to achieve a lower specific fuel consumption; and, a lower number of cylinders — assuming a given output — necessitates or enables a larger cylinder size. It is well known that the increasingly stricter environmental regulations can be met easier in the case of a larger cylinder size. It is doubtless that these considerations mark the significant directions of developing vehicle engines, but they are acting against the - also justified - requirement of smooth running. Our invention provides a solution for eliminating this contradiction. It is to be emphasised that our invention does not replace the well known balancing methods, but it can be applied by retaining, supplementing and in fact enhancing them. Enhancing means that in spite of being aware for many decades already of the processes for balancing the second order mass forces of linearly moving members, they have been, used very rarely in practice. On the basis of our invention, the reason becomes obvious: because in the case of two and three cylinder engines the vibration forces stemming from the unbalanced nature of a change in angular momentum are higher than the vibration forces resulting from the unbalanced second order mass forces, the balancing of the latter could not result in an appropriately smooth running. However, after balancing the angular momentum, it will be worth balancing the second order mass forces and tilting torques, too. We would like to note here that certain members -. cardan shafts, homokinetic articulated shafts, rubber tyres - making up the drive train of vehicles also serve as a torsion spring, and hence the unequal angular velocity of the engine flywheel hardly appears in the imbalance of the torque. Therefore, the vibration transferred to the body of the vehicle is decisively determined by the vibration forces arising on the clamping points of the crankcase. The generally applied flexible clamping of the crankcase extremely efficiently reduces the transferred vibration, and yet this method has its limits. On the one hand, when the engine is started up, the rising angular velocity may take into resonance the swinging system consisting of the flexible clamping and the crankcase, and on the other an excessively soft suspension enables a higher amplitude vibration of the crankcase, which could be the source^' of an air-borne noise. Our invention enables reducing by one magnitude the forces/ torques making the crankcase to vibrate, which substantially reduces both above mentioned disadvantages. The invention is described in details by way of implementation examples, which is the crank drive of a series three-cylinder piston engine depicted by figures, where Fig. 1 is a view of the crank drive of a piston engine, Fig. 2 is a view of the reversing gears without the gear rim, Fig. 3 is a view of a structural detail of the reversing unit, Fig. 4 is a view of the sun wheel of the reversing drive unit, Fig. 5 is the wedging spring unit of the zero-backlash unit,

Fig. 6 shows a change in the resultant of the axial moment vectors acting on a prior art piston engine crankcase, as a function of the crank angle,

Fig. 7 shows a change in the resultant of the axial moment vectors acting on the crankcase of the piston engine embodying the invention, as a function of the crank angle.

The arrangement embodying the invention is shown by way of an implementation example of the crank drive of a three cylinder piston engine, where the arrangement 1 consists of the crankcase type cylinder block 2, the crank drive 3 and the reversing zero- backlash gear drive unit 4, the latter having the first sun wheel 30, the first pseudo epicyclical gears 28, the shafts 26, the inner toothed first gear rim 27 and the casing 24. The cylinder block 2 has only been shown symbolically with a small detail and with its supporting members 17, while the cylinder bores and the main bearings of the crankshaft 5 are not shown. The horizontal pins 6 of the crankshaft 5 fit into the main bearings (not shown) of the cylinder block 2, the crank arms 7 adjoin the horizontal pins 6, the two neighbouring crank arms 7 are connected by the stroke pin 8, to which the connecting rod 9 is fitted, and at the end of the connecting rod stem 11 , there is a small connecting rod eye 12 which fixes the pin 13 turning on a bearing in bore 15 of the piston 14. A counterweight 16 is fitted on the crank arm 7, in the given case fixed in a releasable way, the size of the counterweights 16 is selected in a prior art way, i.e. the crankshaft 5 is dimensioned in a well known way to balance the mass forces resulting from the straight movement of the piston 14, and those stemming from the movement of the connecting rod 9 and connecting rod stem 11. The peripheral division of the stroke pins 8 of the three cylinder crankshaft 5 is of the 120 degree type. With its adjoining formation 20, the first flywheel 21 is fixed torsionally rigidly to the adjoining formation 19 located at the end 18 of the crankshaft 5. The first sun wheel 30 of the reversing zero-backlash gear drive unit 4 engages torsionally rigidly; the adjoining formation 19 of the end 18 of the crankshaft 5, which adjoining formation can be located in the given case on the flywheel 21. The second shaft of the reversing zero-backlash gear drive unit 4, which is represented in the current case by the first gear rim 27, engages torsionally rigidly the second flywheel 22. The angular momentum of the first flywheel 21 and the second flywheel 22 is identical in an absolute sense. The reversing zero-backlash gear drive unit 4 casing 24, which in our example is only a stator frame, is fixed at the adjoining surfaces 25 to the crankcase cylinder block 2 by releasable joints not shown.

The stationary shafts 26 of the reversing zero-backlash gear drive unit 4 are secured to the casing 24, and the first (28) and the second (29) pseudo epicyclical gears are running on bearings on the said stationary shafts. There are three shafts 26 at equal peripheral spacings. The teeth 10 of the first pseudo epicyclical gears 28 engage the teeth 31 of the first sun wheel 30, which joins the first flywheel 21 or it is fixed co-rotationally torsi onally rigidly to the end 18 by releasable fixing members not shown. The teeth 10 of the first pseudo epicyclical gears 28 engage also the teeth 33 of the inner toothed first gear rim 27. The second gear rim 32 has a disc 34 running on bearing on the power output shaft 23, and to the latter torsionally rigidly the second sun wheel 35 is secured, axially located between the disc 34 and the first sun wheel 30. The second gear rim 32 engages torsionally rigidly the first gear rim 27 (shown in^1" one piece in the figure). The teeth 31 of the second sun wheel 35 engage the teeth 10 of the second pseudo epicyclical gears 29. The second gear rim 32, the second pseudo epicyclical gears 29 and the second sun wheel 35 jointly make up the reversing drive unit 34.

The tangentially moving wedging unit 36 arranged between the first (30) and second

(35) sun wheels is designed as a recess 39 confined by the supporting tangential surfaces 38 located in the disc 37 of the first sun wheel 30, and as a nose 42 having a supporting tangential surface 41 and arranged on the disc 40 of the second sun wheel 35 protruding therein. The spanner spring 43 is fitted between the two facing support surfaces 38 and 41, and the largest displacement of the spanner spring 43 is selected in a way that it is longer than the extent necessary for the joint backlash switching of the teeth 31 of the first 30 and second 35 sun wheels, the teeth 10 of the first 28 and second

29 pseudo epicyclical gears and the teeth 33 of the first 27 and second 32 gear rims.

The spanner spring 43 arranged between the two facing support surfaces 38 and 41 is designed as a Belleville spring/spring column.

The angular momentum of the first flywheel 21 and the second flywheel 22 is selected to be identical in a way that the angular momentum of all the members rotating in the same (identical) direction with it is to be included in the angular momentum of each, i.e. the angular momentum of the first flywheel 21 includes the angular momentum of the crankshaft 5, the counterweight 16, the first sun wheel 30, the second sun wheel 35, and the power output shaft 23, i.e. the angular momentum of these units is added to that of the said first flywheel 21. The angular momentum of the second flywheel 22 includes that of the first 28 and second 29 pseudo epicyclical gears, the first gear rim 27 and the second gear rim 32.

The arrangement.1 functions as follows:

The combustion exerts its pressure on the pistons 14, and as a result the angular velocity increases slightly. Next, a proportional angular velocity change of opposite direction arises on the second flywheel, i.e. the angular momentum of the arrangement 1 does not change. This is because the first flywheel 21 and the first sun wheel 30 fixed on the crankshaft 5 turn counterclockwise - when viewed from the flywheel end of the crankshaft 5 - and the first 28 and the second 29 pseudo epicyclical gears turn clockwise on the stationary shafts 26. The inner toothed gear rims 27 and 32 also turn clockwise, and this represents part of the second flywheel 22, the second pseudo epicyclical gears 29 driven by it drive the second sun wheel 35, which turns opposite (counterclockwise), but in an identical direction with the crankshaft 5. The power output shaft 23 fixed to the second sun wheel 35 turns together with the former, which carries the output torque, by which it drives the work equipment not shown. Balance with the output torque is kept by the shafts 26 carrying the first 28 and second 29 pseudo epicyclical gears, and by the casing 24 carrying them, via its supporting members 17. The zero-backlash torsionally rigid relationship is provided by the wedging unit 36 arranged between the first sun wheel 30 and the second sun wheel 35, as well as by the torque guided across them to drive the machine.

The arrangement 1 has the advantage that when fitted into the vehicle, the sense of rotation of the power output shaft 23 is identical with that of the crankshaft 5. The preferential functional result achieved by the arrangement 1 is shown clearly by comparing the torque diagrams shown in Figs. 6 and 7. m Fig. 6, as a function of the angular displacement (Φ), the torque acting on the prior art three cylinder four stroke series engine crankshaft and the crankcase cylinder block as well as on the support members thereof is shown by curve A, while curve B depicts the torque taken from the flywheel. In Fig. 7, as a function of the angular displacement, the torque of the arrangement 1 - in the implementation example in the case of a three cylinder four stroke series engine - acting on the crankcase 2 and on its support members 17 is depicted by curve C, while curve D shows the torque taken from the power output shaft 23.

It is a precondition of the operation above that even the smallest change in the angular velocity of the first flywheel 21 is followed by the second flywheel 22 of opposite rotation, in spite of the high frequency and the extremely low amplitude, the magnitude of which in the case of internal combustion piston engines in the car category is 0.01 radian. Consequently, for example in the case of a gear of 100mm diameter, the tangential direction vibration amplitude is 50 x 0.01 rad = 0.5mm, which is comparable with the size of the usual backlash, that is approx. 0.15 to 0.4mm. In the case of a usual second flywheel located on a blind shaft with a gear drive unit having a backlash, the balancing of the angular momentum cannot be achieved. To balance the angular momentum, according to our invention an appropriately accurate toothing is required, along with ensuring that the torque transferred by the reversing drive unit does not change sign for a single moment.

In one group of piston engines, like for example the free piston mechanical rectifier engine (e.g. patent description US 3,868,932) or crank drive engines having more than three cylinders, the pre-stressing resulting from the series energy flow according to the invention - even without pre-stressing the spring — could be sufficient to ensure a zero- backlash operation. Our invention only demands from the second flywheel to turn in an opposite direction and that the absolute rate of its angular momentum should be identical with that of the first flywheel. If for example the angular velocity of the second flywheel is ω₂ = -0.4CO₁ the moment of inertia of the second flywheel must be 2.5 times as high as that of the first flywheel. It is to be noted that in this case the first flywheel of the piston engine is able to provide a negative torque of 2.5Mi_oad size to the main shaft of the engine, at the boundary of terminating pre-stressing.^'

Claims

1. Arrangement for (1) piston type machines or power machines, for influencing the force/torque arising during operation on the clamping/supporting members (17) of the cylinder block (2) with a main shaft casing, which arrangement (1) has a main shaft (5) running on bearings in the cylinder block (2) with a main shaft casing, and the said main shaft (5) has a first flywheel (21) connected torsionally and rigidly to it, and it has at least another second flywheel (22), the first (21) and the second flywheel (22) are linked by a dual shaft engaged drive unit (4) and it has an output shaft (23), characterised in that the first (21) and the second flywheel (22) has geometrical axes parallel with each other, and they are preferably identical, the drive reversing mechanism connecting them is designed as a drive unit (4) with permanent momentary ratio transmission, the first flywheel (21) is torsionally and rigidly linked to the first shaft (30) of the reversing drive unit (4) with constant momentary ratio transmission, the second flywheel (22) is torsionally and rigidly connected to the second shaft (27),^ the cylinder block (2) with a main shaft casing is torsionally and. rigidly connected to the gearcase (24) of the reversing drive unit (4) with a constant momentary ratio transmission, the power output shaft (23) is linked torsionally and rigidly or via a drive unit to the second flywheel, the angular momentum of the first (21) and second flywheel (22) is the same in an absolute sense, in a way that the angular momentums of all the unidirectionally turning members are to be imputed in the angular momentum of the first flywheel, and the angular momentum of the second flywheel includes the angular momentum of all the members rotating in the same direction.

2. Piston compressor or internal combustion piston engine, which has a cylinder block (2) with a crankcase, with clamping/supporting members (17); in the former it has a crankshaft (5) running on bearings and on this unit there is a bearing supported connecting rod (9) linked to the piston (14), and it also has a first flywheel (21) connected torsionally and rigidly to the crankshaft (5), the first (21) and second flywheel (22) are connected by a dual shaft engaged drive unit (4) and it also has a power output shaft (23), characterised in that the geometrical axes of the first (21) and second flywhcci \ΔΔ) are parauei wim eacn other, the engaged drive unit is designed as a reversing zero-backlash drive unit (4) with permanent momentary ratio transmission, the first- flywheel (21) is torsionally rigidly connected to the first (input) shaft (30) of the reversing drive unit (4) with constant momentary ratio transmission, the second flywheel (22) is torsionally rigidly connected to the second shaft (27) of the reversing drive unit (4) with constant momentary ratio transmission, the cylinder block (2) with the crankcase is connected torsionally rigidly to the gearcase (24) of the reversing drive unit (4) with constant momentary ratio transmission, the angular momentum of the first (21) and the second flywheel (22) is identical in an absolute sense in a way that the angular momentums of all the unidirectionally turning members are to be imputed in the angular momentum of the first flywheel, and the angular momentum of the second flywheel includes the angular momentum of all the members rotating in the same direction.

3. An arrangement according to any of the Claims 1-2 or a compressor or motor characterised in that the reversing drive unit (4) with constant momentary ratio transmission is designed as a zero-backlash gear drive unit.¹

4. A compressor or motor according to Claim 2 characterised in that the reversing zero-backlash gear drive unit (4) is designed as a pseudo epicyclical drive unit, the first sun wheel (30) of which is rigidly fixed to th6 crankshaft (5), and the outer gear teeth (31) of the former engage the outer gear teeth (10) of the first pseudo epicyclical gears (28), which said outer teeth (10) engage the inner gear teeth (33) of the first gear rim (27) to which the second flywheel (22) is connected torsionally and rigidly, the shafts (26) of the first pseudo epicyclical gears (28) are secured to the gearcase (24) rigidly fixed to the cylinder block (2) with' the crankcase and preferably on the same shafts (26) second pseudo epicyclical gears (29) are embedded, the teeth (10) of which engage the teeth (33) of the second gear rim (32), the first gear rim (27) and the second gear rim (32) are connected with each other torsionally rigidly, the teeth (10) of the second pseudo epicyclical gears (29) engage the teeth (31) of the second sun wheel (35), hence designed as a reversing drive unit (34), .the power output shaft (23) is i connected torsionally rigidly to the second sun wheel (35), a tangential wedging unit (36) is fitted between the first (30) and second sun wheel (35) by a force and motion transmission, and this unit (36) makes sure that there is no backlash between the teeth of the reversing gear drive unit (4) with constant momentary ratio transmission and the reversing drive unit (34).

5. The compressor or motor according to Claim 3 characterised in that the tangential wedging unit (36) arranged between the first (30) and second sun wheel (35) is designed with support surfaces (38) as a confined recess (39) in one of the wheel disks (37) and into this protrudes a nose ^"(42) which has a support surface (41) arranged on the second wheel disk (40); a spanner spring (43) is mounted between the two opposite support surfaces (38, 41) and the largest displacement of the spanner spring (43) is chosen in a way that it is more than the displacement necessary for the joint backlash switching of the following parts: the teeth (31) of the first sun wheel (30) and second sun wheel (35), the teeth (10) of the first and second pseudo epicyclical gears (28, 29) and the teeth (33) of the first and second gear rims (27, 32).

6. The compressor/motor according to Claim 4 characterised in that the spanner spring (43) is arranged between the two opposite support surfaces (38, 41).