WO2017085364A1

WO2017085364A1 - Combustion engine with curved combustion cylinders

Info

Publication number: WO2017085364A1
Application number: PCT/FR2016/000180
Authority: WO
Inventors: Martial ROBERT
Original assignee: Robert Martial
Priority date: 2015-11-16
Filing date: 2016-11-09
Publication date: 2017-05-26
Also published as: FR3043721B1; FR3043721A1

Abstract

This combustion engine (10) comprises at least one primary combustion cylinder (20) and at least one secondary combustion cylinder (22), each one curved about an axis of curvature (X-X') that the combustion cylinders (20, 22) share in common. The engine (10) also comprises, for the or each primary combustion cylinder (20), a primary drive piston (40) mounted mobile inside the primary combustion cylinder (20) between a first position near a first end (26) of the cylinder (20) and a second position near a second end (28) of the cylinder (20), and, for the or each secondary combustion cylinder (22), a secondary drive piston (42) mounted mobile inside the secondary combustion cylinder (22) between a first position near a first end (26) of the cylinder (20) and a second position near a second end (28) of the cylinder (20). Each of the primary and secondary drive pistons (40, 42) belongs to an oscillating member (14) mounted with rotational mobility with respect to the combustion cylinders (20, 22) about the axis of curvature (X-X'), the primary and secondary drive pistons (40, 42) being arranged in such a way that when the primary drive piston (40) is in its first position, the secondary drive piston (42) is in its second position, and vice versa.

Description

Incinerated combustion engine with combustion cylinders

The present invention relates to an explosion engine, of the type comprising:

at least one primary combustion cylinder and at least one secondary combustion cylinder, each of said combustion cylinders having a first end and a second end,

for each of the combustion cylinders, a fuel injector for injecting a fuel into the combustion cylinder, said injector being placed at the first end of the combustion cylinder,

for the or each primary combustion cylinder, a primary driving piston mounted movably inside the primary combustion cylinder between a first position near the first end and a second position near the second end, and

for the or each secondary combustion cylinder, a secondary drive piston movably mounted inside the secondary combustion cylinder between a first position near the first end and a second position near the second end. Engines of this type are known and commonly used in many fields, such as automotive, marine, railway or aeronautical propulsion, or the generation of electrical energy. These engines are driven by the blast, in each combustion cylinder, a mixture of fuel and combustion fluid (usually air) which propels the piston mounted in said combustion cylinder from its first end to its second end.

Two main types of internal combustion engines are known: the four-stroke engine and the two-stroke engine. In each of these types of engines, the combustion cylinders are straight and the pistons move linearly in these cylinders, the pistons being articulated to a crankshaft allowing the conversion of the rectilinear motion of the pistons into a rotational movement of an engine axis. The guide of the piston in the combustion cylinder is carried out by the cylinder itself, which requires a very precise dimensioning of the parts to prevent their blockage and makes it essential lubrication of the assembly to minimize friction. A lubrication of the parts is also necessary at the piston-crankshaft joint, no ball bearing can not be installed at this location because of the violence of shocks caused on this joint by the explosion of the fuel mixture-oxidant fluid. This lubrication is ensured by means of an oil, which, for the four-stroke engine, is contained in a crankcase and must be changed regularly and which, for the two-stroke engine is injected into the combustion cylinders at the same time as the fuel.

The four-stroke engine is so called because its cycle is broken down into four main stages (intake, compression, combustion, exhaust) requiring two round trips of the piston in the combustion cylinder. These multiple movements of the piston within a single cycle cause significant energy losses due to the friction of the constituent parts of the engine between them. It is estimated between 55 and 65% friction energy losses for recent four-stroke engines, and over 75% for older engines still in service today.

The cycle of the two-stroke engine is broken down into only two main stages (intake-compression and combustion-exhaust) and thus has the advantage of reducing the movements of the piston during the cycle, and therefore the energy losses by friction. The yield losses by friction of a two-stroke engine are thus theoretically less than half that of a four-stroke engine. This type of engine, however, has the disadvantage of being very polluting, because of the poor quality of the combustion of the oil injected into the engine to lubricate it, and because of fuel leakage passing directly into the fuel system. exhaust without being previously burned, these leaks also making the engine fuel-hungry.

As can be seen, existing explosion engines thus have many disadvantages: low yields, significant pollution, significant consumption of fuel. Another disadvantage of these known engines is their cost, because of the precise machining of pistons and combustion cylinders necessary for a guide without locking the pistons in their cylinders.

An object of the invention is to provide an explosion engine with improved efficiency. Another objective is that this combustion engine has a reduced cost.

For this purpose, the subject of the invention is an explosion engine of the aforementioned type, in which each of the combustion cylinders is curved around a common axis of curvature for the combustion cylinders, and in that each of the driving pistons primary and secondary part belongs to an oscillating member rotatably mounted relative to the combustion cylinders around the axis of curvature, the primary and secondary drive pistons being arranged so that when the primary drive piston is in its first position, the secondary drive piston is in its second position, and vice versa.

According to particular embodiments of the invention, the combustion engine also has one or more of the following characteristics, taken separately or in any combination (s) technically possible (s): a space is provided at the periphery of each of the primary and secondary drive pistons between said primary or secondary drive piston and a curved cylindrical wall of the primary or secondary combustion cylinder inside which said driving piston is mounted,

each of the combustion cylinders has a feed inlet of the combustion cylinder with oxidizing fluid,

the combustion engine comprises, for each of the combustion cylinders, a supply system for said combustion cylinder with combustion fluid, said supply system comprising:

a cylindrical chamber for receiving the oxidizing fluid, said cylindrical chamber having a proximal end and a distal end and having a volume greater than an internal volume of the combustion cylinder, an inlet duct of the oxidizing fluid in the cylindrical chamber, opening in the proximal end of the cylindrical chamber,

an outlet duct of the combustion fluid outside the cylindrical chamber, fluidly connecting the proximal end of the cylindrical chamber to the supply inlet of the combustion cylinder, and

a supply piston displaceable inside the cylindrical chamber between its proximal and distal ends, said supply piston being mounted on the oscillating member so that when the corresponding driving piston is in its first position , the supply piston is near the distal end of the cylindrical chamber and, when the corresponding drive piston is in its second position, the supply piston is close to the proximal end of the cylindrical chamber ,

the cylindrical chamber is curved around the axis of curvature and the supply piston is integral with the oscillating member,

the supply system comprises a non-return valve to prevent the combustion fluid contained in the cylindrical chamber from being forced back into the inlet duct,

the cylindrical chamber has a volume greater than the volume of the combustion cylinder fed by the supply system,

the supply inlet of the combustion cylinder is formed in the first end of the combustion cylinder,

each of the combustion cylinders comprises a curved cylindrical wall in which is provided an outlet for the combustion products outside the combustion cylinder, the combustion engine comprises, for each combustion cylinder, an ignition member placed at the first end of the combustion cylinder,

the combustion engine comprises a shaft for supporting the oscillating member, fixed with respect to the combustion cylinders and substantially coaxial with the axis of curvature, and a ball bearing interposed between the support shaft and the oscillating member; ,

the oscillating member is in one piece,

the primary and secondary combustion cylinders are arranged symmetrically with respect to one another relative to a plane of symmetry of the cylinders fixed with respect to the combustion cylinders and including the axis of curvature, and

- The primary and secondary pistons are arranged symmetrically relative to each other relative to a fixed plane of symmetry of the pistons relative to the oscillating member and including the axis of curvature.

Other features and advantages of the invention will appear on reading the description which follows, given solely by way of example and with reference to the appended drawings, in which:

Figure 1 is a schematic partial sectional view of an engine according to a first embodiment of the invention, the engine being in a first configuration,

FIG. 2 is a view similar to that of FIG. 1, the motor being in a second configuration,

FIG. 3 is a view similar to that of FIG. 1, the motor being in a third configuration,

Figure 4 is a schematic partial sectional view of an engine according to a second embodiment of the invention, and

Figure 5 is a schematic partial sectional view of an engine according to a third embodiment of the invention.

The engine 10 shown in Figure 1 is an explosion engine. This motor 10 is, in the example shown, embedded in a motor vehicle. Alternatively, the engine 10 is on board another type of vehicle, such as a boat or an aircraft, or integrated with a generator or a mobile tool such as a chainsaw or a lawn mower.

The motor 10 comprises a frame 12 and an oscillating member 14 mounted to move relative to the frame 12 between two extreme positions, represented in FIGS. 1 and 3. All the parts of the frame 12 are fixed relative to one another and the pieces of the oscillating member 14 are also fixed relative to each other. The frame 12 comprises a primary combustion cylinder 20 and a secondary combustion cylinder 22. Each cylinder 20, 22 comprises a cylindrical wall 24 centered on a central axis AA 'of the cylinder, and two axial ends 26, 28 flanking the cylindrical wall 24 , said axial ends 26, 28 comprising a first end 26 and a second end 28. The cylindrical wall 24 preferably has a radial section, taken in a radial plane perpendicular to the central axis A-A ', circular or oval.

Each of these cylinders 20, 22 is curved around an axis of curvature X-X 'common to said cylinders 20, 22; in other words, the central axis AA 'of each of the cylinders 20, 22 is curved in a plane orthogonal to the axis X-X', said central axis AA 'having as center of curvature a point of the axis XX '. Each of the cylinders 20, 22 has a regular curvature; in other words, the radius of curvature of the cylinder 20, 22, that is to say the distance from its central axis AA 'to the axis X-X', is substantially equal for any point of the combustion cylinder 20, 22.

Each cylinder 20, 22 also has an inlet 30 for supplying the cylinder 20, 22 with oxidizing fluid, and an orifice 32 for the exit of the combustion products from the cylinder 20, 22. In the example shown, the inlet of supply 30 is formed in the first end 26 of the cylinder 20, 22, and the outlet port 32 is formed in the cylindrical wall 24.

The primary and secondary combustion cylinders 20, 22 are arranged symmetrically with respect to each other relative to a plane P _c of symmetry of the cylinders fixed relative to the frame 12 and including the axis of curvature X-X '.

The oscillating member 14 is mounted to move relative to the frame 12 in rotation around the axis X-X '. For this purpose, the frame 12 comprises a shaft 34 for supporting the oscillating member 14, substantially coaxial with the axis XX 'and around which is mounted the oscillating member 14. Preferably, a ball bearing 36 is, as shown, interposed between the support shaft 34 and the oscillating member 14, so as to avoid friction between these two parts.

The oscillating member 14 is preferably monobloc.

The oscillating member 14 comprises an arm 38 extending substantially radially from the support shaft 34 and two driving pistons 40, 42 each extending substantially orthoradially from the arm 38 opposite the arm 38.

The arm 38 is arranged so that, for each combustion cylinder 20, 22, the second end 28 of the cylinder 20, 22 is closer to the arm 38 than its first end 26. The driving pistons 40, 42 are each engaged in a respective combustion cylinder 20, 22: one thus distinguishes a primary driving piston 40, engaged in the primary combustion cylinder 20, and a secondary driving piston 42, engaged in the secondary combustion cylinder 22.

Each drive piston 40, 42 comprises a piston head 44, wide, and a rod 46 for connecting the piston head 44 to the arm 38, narrow. The piston head 44 has substantially a cylinder shape whose axis is oriented orthoradially with respect to the axis of curvature XX 'and whose diameter is smaller than the internal diameter of the combustion cylinders 20, 22, so that space is provided at the periphery of the piston head 44 between said piston head 44 and the cylindrical wall 24 of the combustion cylinder 20, 22 in which the driving piston 40, 42 is engaged.

Each driving piston 40, 42 extends through the second end 28 of the combustion cylinder 20, 22 in which it is engaged. It is mounted movably inside said combustion cylinder 20, 22 between a first position, in which the piston head 44 is close to the first end 26 of the cylinder 20, 22, and a second position, in which the head of piston 44 is close to the second end 28 of the cylinder 20, 22.

Each piston 40, 42 carries at its periphery sealing members 48 for sealing between the piston 40, 42 and the cylinder 20, 22 in which it is engaged. These sealing members 48 are preferably housed, as shown, in peripheral grooves formed in the piston head 44. These sealing members 48 are typically segments, as conventionally used in combustion engines.

The primary and secondary drive pistons 40, 42 are arranged such that when the primary drive piston 40 is in its first position, the secondary drive piston is in its second position 42, and vice versa. For this purpose, the primary and secondary drive pistons 40, 42 are arranged symmetrically with respect to each other with respect to a plane P _P symmetry plane fixed relative to the oscillating member 14 and including the 'X-X axis'.

In the example shown, the plane of symmetry Pp includes the radial axis of extension of the arm 38, so that the pistons 40, 42 extend orthoradially in opposite directions from the arm 38.

There is at least one position of the oscillating member 14 with respect to the frame 12 in which the plane of symmetry P _P and P _c coincide.

The engine 10 also comprises, for each of the combustion cylinders 20,

22, a system 50A, 50B supplying said combustion cylinder 20, 22 in fluid oxidizer. This supply system 50A, 50B comprises a cylindrical chamber 52A, 52B for receiving the oxidizing fluid, a conduit 54A, 54B for entering the oxidizing fluid into the cylindrical chamber 52A, 52B, a conduit 56A, 56B for discharging the oxidizing fluid. out of the cylindrical chamber 52A, 52B, and a supply piston 58A, 58B movable within the cylindrical chamber 52A, 52B. There is a primary power supply system 50A, comprising a primary cylindrical chamber 52A, a primary inlet duct 54A, a primary outlet duct 56A and a primary supply piston 58A, for supplying the primary combustion cylinder 20 , and a secondary supply system 50B, comprising a secondary cylindrical chamber 52B, a secondary inlet duct 54B, a secondary outlet duct 56B and a secondary supply piston 58B, for supplying the secondary combustion cylinder 22 .

For each supply system 50A, 50B, the cylindrical chamber 52A, 52B, the inlet duct 54A, 54B and the outlet duct 56A, 56B belong to the frame 12, the supply piston 58A, 58B belonging to him to the oscillating member 14.

The cylindrical chamber 52A, 52B is bordered by a cylindrical wall 60 centered on a central axis CC of the chamber, and extends between two axial ends 62, 64 surrounding the cylindrical wall 60, said axial ends 62, 64 comprising a proximal end 62 near the inlet conduits 54A, 54B and output 56A, 56B, and a distal end opposite the inlet conduits 54A, 54B and output 56A, 56B. The cylindrical wall 60 has a radial section, taken in a radial plane perpendicular to the central axis C-C, which is preferably circular or oval.

The cylindrical chamber 52A, 52B is curved around the axis of curvature X-X '; in other words, the central axis CC of the chamber 52A, 52B is curved in a plane orthogonal to the axis X-X ', said central axis CC having as center of curvature a point of the X-X axis . The cylindrical chamber 52A, 52B has a regular curvature; in other words, the radius of curvature of the cylindrical chamber 52A, 52B, that is to say the distance from its central axis CC to the axis X-X ', is substantially equal for every point of the chamber cylindrical 52A, 52B.

The cylindrical chamber 52A, 52B is preferably arranged, as shown, at a distance from the axis X-X 'greater than the distance of the cylinder 20, 22 that it feeds the axis X-X'.

The cylindrical chamber 52A, 52B has a volume greater than the volume of the cylinder 20, 22 that it feeds.

In the example shown, the primary cylindrical 52A and secondary 52B chambers are arranged symmetrically with respect to each other with respect to the plane of symmetry P _c . The inlet conduit 54A, 54B and the outlet conduit 56A, 56B both open into the proximal end 62 of the cylindrical chamber 52A, 52B. The outlet duct 56A, 56B thus fluidically connects the proximal end 62 of the cylindrical chamber 52A, 52B to the supply inlet 30 of the cylinder 20, 22 supplied by the supply system 50A, 50B.

The supply piston 58A, 58B extends substantially orthoradially from the arm 38 opposite the arm 38. It comprises a piston head 66, wide, and a rod 67 connecting the piston head 66 to the arm 38 , narrow. The piston head 66 has substantially a cylinder shape whose axis is oriented orthoradially with respect to the axis of curvature XX 'and whose diameter is smaller than the inside diameter of the cylindrical chamber 52A, 52B, so that space is provided at the periphery of the piston head 66 between said piston head 66 and the cylindrical wall 60 bordering the cylindrical chamber 52A, 52B.

The supply piston 58A, 58B carries at its periphery a sealing member 68 for sealing between the piston 58A, 58B and the cylindrical wall 60. This sealing member 68 is preferably housed, as shown in FIG. a peripheral groove formed in the piston head 66. This sealing member 68 is typically a segment, as conventionally used in combustion engines.

The supply piston 58A, 58B is mounted on the arm 38 so that when the driving piston 40, 42 engaged in the cylinder 20, 22 fed by the supply system 50A, 50B is in its first position, the supply piston 58A, 58B is in proximity to the distal end 64 of the cylindrical chamber 52A, 52B and, when said drive piston 40, 42 is in its second position, the supply piston 58A, 58B is near the proximal end 62 of the cylindrical chamber 52A, 52B. For this purpose, in the example shown, the supply piston 58A, 58B extends from the arm 38 in the same direction as the driving piston 40, 42 engaged in the cylinder 20, 22 fed by the control system. 50A, 50B, and the cylindrical chamber 52A, 52B is disposed so that its proximal end 62 is closer to the arm 38 than its distal end 64; this configuration makes it possible to maximize the compactness of the motor 10. The proximal end 62 of the cylindrical chamber 52A, 52B is then provided, as shown, with a sealing element sealing between the proximal end 62 and the piston supply 58A, 58B.

The supply system 50A, 50B also comprises a non-return valve 69 disposed in the supply duct 54A, 54B to prevent the combustion fluid contained in the cylindrical chamber 52A, 52B from being forced back into the inlet duct 54A, 54B when the supply piston 58A, 58B is brought closer to the proximal end 62 of the chamber 52A, 52B.

The oxidizing fluid is typically air.

Alternatively (not shown), each supply system 50A, 50B is constituted by a turbocharger.

The engine 10 also includes a valve system 70 for regulating the combustion fluid inlets and the combustion product outlets in and out of the cylinders 20, 22.

This valve system 70 comprises, for each cylinder 20, 22, an inlet valve 72 and an outlet valve 74. The valve system 70 also comprises a system 76 for driving the inlet and outlet valves 72 and 74 each cylinder 20, 22.

The inlet valve 72 is mounted movably relative to the frame 12 between a closed position in which it closes the supply inlet 30 of the cylinder 20, 22 and an open position in which it releases the supply inlet 30. The outlet valve 74 is mounted movably relative to the frame 12 between a closed position in which it closes the outlet orifice 32 of the cylinder 20, 22 and an open position in which it releases the outlet orifice 32.

The drive system 76 is adapted to move the inlet 72 and outlet 74 valves between their respective obstruction and release positions. For this purpose, the drive system 76 comprises, in the example shown, a cam and gear system that is slaved to the movements of the oscillating member 14 via a crank-rod device 78. (Not shown), the drive system 76 comprises a distribution chain, or a solenoid displacement system controlled by the movements of the oscillating member 14 by means of a position sensor adapted to identify the position of the organ oscillating 14.

The engine 10 also comprises, for each cylinder 20, 22, a fuel injector 80 for injecting a fuel into the interior of said cylinder 20, 22 and, in the example shown, an ignition member 82 for engaging the combustion in the cylinder 20, 22.

The injector 80 and the igniter 82 are both located at the first end 26 of the combustion cylinder 20, 22.

The engine 10 also comprises a starter 84. This starter 84 is formed, in the example shown, by a toothed gear geared to the drive system of the valves 76 and driven by an electric motor (not shown) fed by a battery of start (not shown). The engine 10 further comprises a system 86 for charging the starter battery. This charging system 86 comprises, in the example shown, a gear gear meshing on the drive system of the valves 76 and driving an alternator (not shown) electrically connected to the starter battery.

The motor 10 finally comprises a motor shaft (not shown), extending along an axis substantially parallel to the axis XX 'and rotatably mounted relative to the frame 12 about said axis, and a member 90 for converting the oscillations of the oscillating member 14 in a rotation of the motor shaft about its axis. This conversion member 90 is, in the example shown, formed by a connecting rod-crank system consisting of an angled connecting rod 92, articulated by a first pivot point 94 to the oscillating member 14 so as to be pivotable relative to the oscillating member 14 about an axis substantially parallel to the axis X-X ', and a crank 96, integral with the shaft and articulated to the connecting rod 92 by a second pivot point 98 spaced from the first pivot point 94 so as to be pivotable relative to the connecting rod 92 about an axis substantially parallel to the axis X-X '.

The drive shaft is preferably kinematically connected to an alternator 100 of the vehicle so that the drive shaft and the alternator 100 rotate jointly about their respective axes; this kinematic connection is typically formed by a gear, a transmission belt, or a direct connection of the motor shaft to the rotor of the alternator 100. The alternator 100 is, in the example shown, electrically connected to an electric battery 102 of electric motor supply 104 driving the wheels 106 of the motor vehicle, each electric motor 104 being advantageously clean to a wheel 106 of the vehicle.

The operation of the motor 10 will now be described with reference to Figures 1 to 3.

The engine 10 is initially started and is in a first configuration, shown in FIG. 1, in which the primary driving piston 40 is in its first position and the secondary driving piston 42 is in its second position. The inlet 72 and outlet 74 valves of the primary cylinder 20 are closed, and the inlet 72 and outlet 74 valves of the secondary cylinder 22 are open.

The ignition member 82 is then activated, which triggers a deflagration of the fuel-oxidant mixture present in the primary cylinder 20. Under the effect of this deflagration, the primary driving piston 40 is propelled away from the first end 26 of the primary piston 20. In doing so, it is the assembly of the oscillating member 14 which pivots about the axis X-X ', in a first direction, and thus the supply piston 58A primary moves to the proximal end 62 of the primary cylindrical chamber 52A, the secondary drive piston 42 moves to the first end 26 of the secondary cylinder 22, and the secondary supply piston 58B moves to the end distal 64 of the secondary cylindrical chamber 52B.

As soon as the movement movement of the secondary drive piston 42 to the first end 26 of the secondary cylinder 22 starts, the inlet and outlet valves 72, 74 of the secondary cylinder 22 close. The oxidant fluid present in the secondary cylinder 22 is then compressed by the displacement of the secondary drive piston 42 towards the first end 26 of the cylinder 22.

At the same time, the displacement of the secondary supply piston 58B towards the distal end 64 of the secondary cylindrical chamber 52B causes a depression in the chamber 52B, under the effect of which the non-return valve 69 opens, thus allowing the entry of oxidizing fluid which fills the secondary cylindrical chamber 52B.

When the piston head 44 of the primary drive piston 40 passes the outlet port 32, as shown in FIG. 2, the inlet 72 and outlet 74 valves of the primary cylinder 20 open. The oxidant fluid contained in the primary cylindrical chamber 52A, which is compressed by the displacement of the primary supply piston 58A towards the proximal end 62 of the chamber 52A, then enters the primary cylinder 20 via its feed inlet 30 and fills the primary cylinder 20 by expelling the combustion products, which escape through the outlet port 32.

When the piston head 44 of the secondary drive piston 42 passes the outlet port 32, the injector 80 of the secondary cylinder 22 injects fuel into the secondary cylinder 22. Then, when the secondary drive piston 42 reaches its first position, as shown in Figure 3, the ignition member 82 of the secondary cylinder 22 is activated.

This activation of the ignition member 82 triggers a deflagration of the fuel-oxidant mixture present in the secondary cylinder 22, under the effect of which the secondary drive piston 42 is propelled away from the first end 26 of the secondary cylinder 22. In doing so, it is the assembly of the oscillating member 14 which pivots about the axis X-X ', in a second direction opposite to the first. Thus, the primary drive piston 40, which had reached its second position, returns to its first position, the primary supply piston 58A, which had reached the proximal end 62 of the primary feed chamber 52A, returns to its first position. the distal end 64 of this chamber 52A, and the secondary supply piston 58B, which had reached the distal end 64 of the secondary supply chamber 52B returns to the proximal end of this chamber 52B.

As soon as the movement movement of the primary drive piston 40 to the first end 26 of the primary cylinder 20 begins, the inlet and outlet valves 72, 74 of the primary cylinder 20 close. The oxidizing fluid present in the primary cylinder 20 is then compressed by the displacement of the primary drive piston 40 towards the first end 26 of the cylinder 20.

At the same time, the displacement of the primary supply piston 58A towards the distal end 64 of the primary cylindrical chamber 52A causes a depression in the chamber 52A, under the effect of which the non-return valve 69 opens, thus allowing the entry of combustion fluid which fills the primary cylindrical chamber 52A.

When the piston head 44 of the secondary drive piston 42 passes the outlet port 32, the inlet 72 and outlet 74 valves of the secondary cylinder 22 open. The oxidant fluid contained in the secondary cylindrical chamber 52B, which is compressed by the displacement of the secondary supply piston 58B towards the proximal end 62 of the chamber 52B, then enters the secondary cylinder 22 via its feed inlet 30 and fills the secondary cylinder 22 by expelling the combustion products, which escape through the outlet port 32.

When the piston head 44 of the primary drive piston 40 passes the outlet port 32, the injector 80 of the primary cylinder 20 injects fuel into the primary cylinder 20. Then, when the primary drive piston 40 reaches its first position, the ignition member 82 of the primary cylinder 20 is activated again: the previous steps are repeated.

The embodiments shown in Figures 4 and 5 are variants of the engine 10 in which the engine 10 comprises a plurality of primary combustion cylinders 20 and a plurality of secondary combustion cylinders 22. It should be noted that, in these variants, the primary and secondary combustion cylinders 22 are in equal numbers.

The fact that, in the examples shown, the combustion cylinders 20, 22 are all arranged in the same radial plane to the X-X 'axis is only one embodiment of the invention. Alternatively, the combustion cylinders 20, 22 are arranged in different planes.

Thanks to the invention described above, the friction of parts are minimized: the guiding of the driving pistons 40, 42 being ensured not by the combustion cylinders 20, 22 themselves, but by the pivoting of the organ oscillating 14 around the support shaft 34, at the interface of which is disposed a ball bearing, allows in effect of limiting the friction between the pistons 40, 42 and the cylinders 20, 22 to the only friction necessary to maintain the seal between these parts.

The energy losses by friction are thus minimized, which allows the engine 10 to have a much better performance than conventional explosion engines. In addition, it is not necessary to precisely dimension the pistons 40, 42 and the cylinders 20, 22, which allows to lower the manufacturing cost of these parts and thus the overall cost of the engine 10. Finally, only one Minimal lubrication of the parts is necessary, resulting in significant savings in lubricating product.

Claims

1. - An explosion engine (10) comprising:

at least one primary combustion cylinder and at least one secondary combustion cylinder, each of said combustion cylinders having a first end and a second end;

for each of the combustion cylinders (20, 22), a fuel injector (80) for injecting fuel into the combustion cylinder (20, 22), said injector (80) being located at the first end ( 26) of the combustion cylinder (20, 22),

for the or each primary combustion cylinder (20), a primary drive piston (40) movably mounted within the primary combustion cylinder (20) between a first position proximate the first end (26) and a first second position near the second end (28), and

for the or each secondary combustion cylinder (22), a secondary drive piston (42) movably mounted within the secondary combustion cylinder (22) between a first position near the first end (26) and a second position near the second end (28),

characterized in that each of the combustion cylinders (20, 22) is curved around a common axis of curvature (Χ-Χ ') to the combustion cylinders (20, 22), and in that each of the driving pistons primary and secondary (40, 42) part of an oscillating member (14) rotatably mounted relative to the combustion cylinders (20, 22) about the axis of curvature (Χ-Χ '), the driving pistons primary and secondary (40, 42) are arranged so that when the primary drive piston (40) is in its first position, the secondary drive piston (42) is in its second position, and vice versa.

The combustion engine (10) according to claim 1, wherein a space is provided at the periphery of each of the primary and secondary drive pistons (40,

42) between said primary or secondary drive piston (40,42) and a curved cylindrical wall (24) of the primary or secondary combustion cylinder (20,22) within which said drive piston (40,42) ) has climbed.

3. - A combustion engine (10) according to claim 1 or 2, wherein each of the combustion cylinders (20, 22) has an inlet (30) for supplying the combustion cylinder (20, 22) with oxidizing fluid.

4. - A combustion engine (10) according to claim 3, comprising, for each of the combustion cylinders (20, 22), a system (50A, 50B) for supplying said combustion cylinder (20, 22) with oxidizing fluid. said supply system (50A, 50B) comprising:

a cylindrical chamber (52A, 52B) for receiving the oxidizing fluid, said cylindrical chamber (52A, 52B) having a proximal end (62) and a distal end (64) and having a volume greater than an internal volume of the combustion cylinder (20, 22),

a conduit (54A, 54B) for entering the oxidizing fluid into the cylindrical chamber (52A, 52B), opening into the proximal end (62) of the cylindrical chamber (52A, 52B),

a conduit (56A, 56B) for exiting the oxidant fluid from the cylindrical chamber (52A, 52B), fluidically connecting the proximal end (62) of the cylindrical chamber (52A, 52B) to the supply inlet ( 30) of the combustion cylinder (20, 22), and

a supply piston (58A, 58B) movable within the cylindrical chamber (52A, 52B) between its proximal and distal ends (62, 64), said supply piston (58A, 58B) being mounted on the oscillating member (14) so that when the corresponding driving piston (40, 42) is in its first position, the supply piston (58A, 58B) is near the distal end (64) of the cylindrical chamber (52A, 52B) and, when the corresponding driving piston (40, 42) is in its second position, the supply piston (58A, 58B) is close to the proximal end (62) of the cylindrical chamber (52A, 52B).

The combustion engine (10) according to claim 4, wherein the cylindrical chamber (52A, 52B) is curved about the axis of curvature (Χ-Χ ') and the supply piston (58A, 58B). is integral with the oscillating member (14).

The combustion engine (10) according to claim 4 or 5, wherein the supply system (50A, 50B) comprises a non-return valve (69) for preventing the oxidant fluid contained in the cylindrical chamber (52A, 52B) to be forced back into the inlet duct (54A, 54B).

7. - A combustion engine (10) according to any one of claims 4 to 6, wherein the cylindrical chamber (52A, 52B) has a volume greater than the volume of the combustion cylinder (20, 22) fed by the combustion chamber system. power supply (50A, 50B).

The combustion engine (10) according to any one of claims 3 to 7, wherein the supply inlet (30) of the combustion cylinder (20, 22) is formed in the first end (26) of the combustion cylinder (20, 22).

9. - An explosion engine (10) according to any one of the preceding claims, wherein each of the combustion cylinders (20, 22) comprises a curved cylindrical wall (24) in which an outlet opening (32) is provided. combustion products from the combustion cylinder (20, 22).

10. - A combustion engine (10) according to any one of the preceding claims comprising, for each combustion cylinder (20, 22), an ignition member (82) placed at the first end (26) of the combustion cylinder (20, 22).

1 1. - A combustion engine (10) according to any preceding claim, comprising a shaft (34) for supporting the oscillating member (14), fixed relative to the combustion cylinders (20, 22) and substantially coaxial with the bending axis (Χ-Χ '), and a ball bearing (36) interposed between the support shaft (34) and the oscillating member (14).

12. - Motor explosion (10) according to any one of the preceding claims, wherein the oscillating member (14) is in one piece.

13. - An explosion engine (10) according to any one of the preceding claims, wherein the primary and secondary combustion cylinders (20, 22) are arranged symmetrically relative to each other relative to a plane of symmetry. cylinders (Pc) fixed with respect to the combustion cylinders (20, 22) and including the axis of curvature (Χ-Χ ').

14. - An explosion engine (10) according to any one of the preceding claims, wherein the primary and secondary pistons (40, 42) are arranged symmetrically relative to each other relative to a plane of symmetry of the pistons. (P _P ) fixed relative to the oscillating member (14) and including the axis of curvature (Χ-Χ ').

15. - An explosion engine (10) according to any one of the preceding claims, wherein the first end (26) of each combustion cylinder (20, 22) is closed by a wall extending across the axis. (Α-Α ') of the combustion cylinder (20, 22).