1 Combustion engine having mutually connected pistons Field of the invention The present invention is related to a combustion engine having two sets of mutually connected pistons combined with a steam engine comprising cylinders for combustion and steam. Background The efficiency of the Otto motor is known to be relatively low in relation to the energy of the fuel to be combusted. Several attempts have been made to increase the efficiency. Still, however, combustion engines produce large heat losses to the atmosphere. Engines of the above mentioned type are disclosed e.g. in GB 125 395, GB 125 174, GB 189 373, GB 300 631, US 2 237 014 and DE 10 2004 013 854. Summary of the invention With the combustion engine according to the present invention an efficiency increase is achieved in relation to conventional combustion engines. The combustion engine may be a two-stroke or four-stroke engine with optional type of fuel. In a development a further efficiency increase is obtained by utilization of the large amounts of heat from the combustion process of the combustion engine for operation of a steam engine connected to the combustion engine. In a first aspect, the present invention provides a combustion engine comprising interconnected combustion cylinders, characterized in that at least two sets of combustion cylinders are provided, wherein each set of combustion cylinders are opposed combustion cylinders having pistons interconnected by a common piston rod, wherein said common piston rod in each set of combustion cylinders is connected to a first shared balance arm, which first shared balance arm is connected to a flywheel 2 arm, in turn connected to a flywheel, and in use the exploitable energy is taken from the kinetic energy of said balance arm and flywheel, and wherein at least two sets of two opposed working steam cylinders are provided, each set of two opposed working steam cylinders having a pair of pistons that are connected by a common piston rod, said common piston rod of each set of two opposed working steam cylinders connected to a second shared balance arm, that said first balance arm and said second balance arm being rigidly connected by a connection, wherein each combustion cylinder comprises a heat exchanger having a cooling jacket in contact with the combustion cylinder in fluid connection with an inlet on one of said steam cylinders, wherein said steam cylinder has an outlet in fluid connection with a temperature regulator, in fluid communication with said cooling jacket to form a fluid circuit, wherein in use, the heat from each combustion cylinder vaporises cooling fluid to steam in its cooling jacket, which steam from the cooling jacket is transferred to a steam cylinder and steam finishing a working stroke returns via a temperature regulator to the cooling jacket, having the effect of cooling the combustion cylinder and driving the steam cylinder. Throughout this specification - the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps. Nothing above should be read as necessarily falling within the common general knowledge. Brief description of the drawings The invention is described below with reference to the accompanying drawings, in which: 2a Figure 1 is a block diagram of a combustion engine connected to a steam engine where four cylinders in a two-stroke combustion engine are connected with four cylinders in a steam engine; Figure 2 is a partial block diagram of a flywheel connected to the block diagram arrangement in Figure 1 with a modified common balance arm.
3 Examples The invention is exemplified below with reference to the drawings in non-limiting examples of the implementation of the invention. With reference to Fig. 1, the combustion engine comprises combustion cylinders 1, 2, 3 and 4 where opposed pistons of combustion cylinders 1 and 3 are connected with a common piston rod 5 and pistons of the opposed combustion cylinders 2 and 4 are connected with a common piston rod 6. The piston rods 5 and 6 are connected with a balance arm 7 which coordinate the movements of the piston rods. One end of the balance arm 7 is connected to a flywheel (not shown in Fig. 1). In the interests of simplicity, only the features of combustion cylinder 1 are enumerated. However, each combustion cylinder 2, 3 and 4 has the same features as that in combustion cylinder 1. Combustion cylinder 1 has a cooling jacket 9. Furthermore the combustion cylinder 1 has a valve 10 for fuel, a valve 24 for air inlet to the combustion cylinders and a valve 11 for exhaust gas. A steam engine is connected to the combustion engine. Each cylinder 1, 2, 3 and 4 is connected to an associated steam cylinder 14, 16, 15 and 17, respectively. Again, in the interests of simplicity, only the features of combustion cylinder 1 and its connection with steam cylinder 14 is described. However, each combustion cylinder 2, 3 and 4 and associated steam cylinders 16, 15 and 17 has the same features as that in combustion cylinder 1. The cooling jacket 9 is connected with a heat exchanger 12 (other heat exchangers are provided for each of the combustion cylinders 2, 3 and 4 as 12b, 12a and 12c) where the heated cooling water is further heated by the exhaust gas from the exhaust gas valve 11 until the cooling water is in the state of superheated steam. Cooled exhaust gas thereafter is released to the atmosphere or to other possible use. The superheated steam is transferred to steam cylinder 14 in the steam engine through a pipe line 13. Upon executed work in the steam cylinder 14 steam/condensate is returned to the cooling jacket 9 as cooled condensate.
4 The pistons of the steam cylinders 14 and 15 are connected with a common piston rod 19 and the pistons of steam cylinders 16 and 17 are correspondingly connected with a common piston rod 20. Said piston rods 19 and 20 are connected with a balance arm 18. The rocking movements of the balance arms 7 and 18 are coordinated by a connection 21. In Figure 1, the combustion cylinder 1 is disclosed at the end of a working stroke. The heated cooling water in the cooling jacket 9 is conducted to the heat exchanger 12 through the pipe line 13 and further to the steam cylinder 14. The exhaust gas is flushed out of by air from the air inlet 24 and through a valve to the heat exchanger 12 for heating and vaporization of the cooling water. Thereafter fuel is guided through the valve 10 for compressing and combustion. The steam from the heat exchanger 12, which is transferred through the pipe line 13, brings the steam cylinder 14 to perform a working stroke in the steam cylinder 14 by forcing the piston rod 19 downwardly in the figure whereby the piston rod 5 of the combustion cylinder 1 thereby is pressed upwardly. By the return stroke of the steam cylinder 14, steam from the steam cylinder 14 is forced through the pipe line 22 to a temperature regulator 23 (other heat exchangers are provided for each of the combustion cylinders 2, 3 and 4 as 23a, 23c and 23b) whereby cooled cooling water is transferred from the temperature regulator 23 to the cooling jacket 9 around the combustion cylinder 1. With arm 8, the movements of the mutually connected balance arms 7 and 18 may turn a flywheel (not shown in Fig. 1). The combustion cylinder with the piston connected with the piston rod 5 and the steam cylinder 15 work oppositely of the combustion cylinder 1 and the steam cylinder 14. Correspondingly the combustion cylinder 4 and the steam cylinder 17 work together with the combustion cylinder 1 and the steam cylinder 17 by the heat exchanger 12 and the temperature regulator 23. The combustion cylinder 2 and the 5 steam cylinder 16 work oppositely of the combustion cylinder 1 and the steam cylinder 14. Correspondingly the combustion cylinder 2 of the combustion engine is connected with the steam cylinder 16, the combustion cylinder 3 is connected with the steam cylinder 15 and the combustion cylinder 4 is connected with the steam cylinder 17. Hereby pipe lines correspond with the pipe lines 13, 22 and temperature regulators corresponding with the temperature regulator 23 being connecting the cylinders. The steam cylinder 16 is located on top of the combustion cylinder 2. Balance arm 18 is bolted on top of balance arm 7, so they operate together. The geometry between the connection of the balance arm 7 to the piston rods 5 and 6 and connection of the balance arm 18 to the piston rods 19 and 20 in relation to the turning point of the coordination connection 21 as well as the distance to the turning point of the flywheel arm 8 of the balance arm 7 is optimized as regards to achieving as large moment of force as possible. At the same time the output of the steam engine in relation to the heat development of the combustion engine is optimized thereby to achieve optimal efficiency. With reference to Fig. 2, a simplified block diagram of an engine of the invention is shown. This engine is almost identical to that as shown in Fig. 1. However, in place of two interconnected balance arms 7 and 18 in Fig. 1, there is a single common balance arm 26. Additionally, connected to flywheel arm 8 is a flywheel 25. In use, kinetic energy generated by the operation of the engine can be taken from flywheel 25 and/or balance arm 26. In use, the flywheel 25 may be used to: give a convenient input from a starter mechanism (not shown) to the combustion engine to enable the starting the engine; keep the engine running smoothly; and to absorb vibration, depending on its construction.
6 An art-skilled worker will appreciate that the general teachings in the present invention may be used to create different implementations of the invention without departing from the scope of the invention, which is limited only by the appended claims.