FR2491130A1 - INTEGRATED TURBOCHARGER CYLINDER HEAD - Google Patents

Abstract

A cylinder head (12) in an internal combustion engine containing at least one cylinder comprises a chamber (18) which is suitable for the accommodation of a turbocharger (19), which is designed as an insert. The chamber is connected to the combustion spaces (17) of the engine by way of passages (15, 16), which are controlled or monitored by valves (13, 14) on the cylinder. The chamber is preferably of cylindrical form, at least one end being closed off by a removable part (33 and/or 34), which allows the insert to be pushed in. The turbocharger contains a rotor coil with a compressor wheel (24) and a turbine wheel (25) which are fitted on a common shaft (26) and enclosed in a housing (27). The compressor and turbine wheels are preferably designed so that they have an axial inlet and an axial outlet. Worm-like passages (20, 21) in the enveloping wall of the chamber are opened in the direction of the latter by way of peripheral grooves (22, 23). The housing comprises a central body, which has two radially projecting, peripheral flanges (28, 29), which pass into the grooves and which are preferably provided with guide vanes (30, 31). The chamber may be formed so that the turbocharger is fitted transversely to the engine or at its side, the axis of rotation of the turbocharger lying either vertically or horizontally. A turbocharger may serve one or more cylinders.

Description

 The present invention relates to the supercharging of internal combustion engines, and in particular of motor vehicle engines, where the increased demand for reduction in weight and volume means that the available space is more reduced but where the requirements concerning maintenance and easy replacement of components are high.

 The use of ceramic materials in exhaust pipes, casings and turbine rotors makes it possible to produce light and compact supercharging units, and an object of the present invention is to provide simplified and compact casings capable of supporting the supercharging units and connecting them to the engine making good use of the space available, which are also inexpensive and efficient while simultaneously offering good possibilities for maintenance and troubleshooting.

 A supercharging device according to the invention is characterized in that the lines which communicate with the exhaust and intake openings of the engine are assembled in a casing in one piece, the longitudinal axis of which is substantially parallel to a plane longitudinal median passing through the cylinders, and in which is mounted at least one turbine / compressor assembly comprising an outlet and an inlet directed axially.

 Preferably, the casing comprises a cylindrical cavity, completely open at least at one of its ends, while the turbine / compressor assembly is mounted in a cylindrical housing capable of sliding in the cavity in the axial direction.

 As a variant, the outlet and inlet conauites are individually assembled in one half of a casing which is divided by a plane perpendicular to its longitudinal axis, and includes a cavity provided for directly receiving the rotors of the turbine / compressor assembly .

 When it is a multi-cylinder engine, the exhaust and intake manifolds may include at least two turbine / compressor assemblies operating in parallel.

 The turbocharger housing which projects freely from the engine block is well suited for the connection of a second exhaust turbine at its exhaust end. The shaft of this second turbine can transform the residual energy <a contained in the exhaust gas into mechanical power, for example by being connected to the crankshaft of the engine by means of a reduction gear. Alternatively, the shaft may be arranged to drive at least some of the engine auxiliaries, for example an electric generator, or to drive a hydraulic pump or a flywheel accumulator when it is a generator of hybrid power.

 The invention is described below with reference to the accompanying drawings.

 FIG. 1 schematically represents an internal combustion engine with four cylinders provided with a supercharging device according to the invention.

 Figure 2 is a vertical section of the supercharging assembly according to the invention.

 FIG. 3 represents one half of the casing intended for the turbine / compressor assembly of FIG. 2.

 Figure 4 shows a corresponding section of a modified form of a turbocharger.

 FIG. 5 is an exploded view of the casing and of the turbine / compressor assembly.

 FIG. 6 is a side view of a device illustrating the arrangement of the connection pipes allowing better use of the space available.

 Figure 7 is a horizontal view of an exhaust manifold of a six-cylinder engine and comprising two supercharging assemblies.

 FIG. 8 is a side view of an exhaust and intake manifold according to an arrangement according to FIG. 7.

 Figure 9 shows a possible location for the supercharger when it is a V-engine.

 FIG. 10 represents an engine similar to that of FIG. 1 but comprising a second exhaust gas turbine capable of being driven by the flywheel of the engine.

 FIG. 11 shows on a slightly larger scale a combustion chamber disposed between the turbocharger and the second gas turbine of FIG. 10.

 FIG. 12 represents a three-cylinder engine comprising a supercharging assembly and a second gas turbine driving an auxiliary.

 FIG. 13 shows on a slightly larger scale the combustion chamber disposed between the turbocharger and the second exhaust gas turbine of FIG. 12.

 Figure 14 shows a motor corresponding to that of Figure 12, but whose rotor shafts are arranged horizontally.

 FIG. 15 is a diagrammatic section of the turbocharger of FIG. 14.

 FIG. 16 represents a double volute intended to transfer the gases from the turbine of the turbocharger to the second exhaust turbine.

 Figure 17 shows a modified arrangement of the rotor assembly.

 FIG. 1 very schematically represents an internal combustion engine with four cylinders 10, comprising a supercharging device 11 arranged according to the invention.

The exhaust and intake openings are assumed to be located on the same side of a longitudinal median plane passing through the engine, and to illustrate this principle, the exhaust pipes 12 and the air pipes 13 are more strongly separated. than this is the case in a practical embodiment. The device 11 is arranged so that its longitudinal axis is vertical and an exhaust pipe 14 is fixed at its lower end, while a pipe 15 coming from an air filter and / or a carburetor is fixed to its upper end. This arrangement makes it possible to obtain a compact installation comprising a minimum of pipes, in comparison with current installations of turbochargers.

 The turbocharger assembly comprises a rotor core 16 comprising a turbine wheel 17 and a compressor wheel 18 which are mounted on a common shaft 19. The core of the turbine, in the embodiment shown in FIG. 2, is mounted in a cylindrical housing 20 which is divided in any suitable manner, for example along a longitudinal median plane, so as to easily enclose the core 16 of the rotor.

 The air pipes 13 and the exhaust pipes 12 are formed inside a casing 21, which is produced here in a single piece but which can optionally be divided along a plane perpendicular to the axis of the rotor. In the latter case, it comprises a first half to which the air pipes 13 are connected and a second half to which the exhaust pipes are connected 12. In the embodiment shown, the casing 21 comprises a cylindrical chamber 22 in which the rotor housing can slide through the upper part, so as to rest on a support suitable for the lower part of the casing, or on a flange provided at its upper part. The rotor housing 20 is provided with blades and / or suitable guide passages which adapt against corresponding passages in the wall defining the cavity 22.

 Figure 3 shows one half of a housing 20 of the rotor, the friend of the rotor having been removed.

 In the modified embodiment shown in Figure 4, the air and exhaust pipes 13 and 12 respectively are each formed by two halves 25 and 26 which together form the casing of the supercharging assembly. In this case, the housing halves are shaped inside so as to directly receive the wheels 17, 18 of the rotor and to cooperate with them. Between the latter is provided a space for a bearing 27 which is mounted in the enveloping half 25 of the casing.

 Figure 5 is an exploded view of the components of Figure 4. Annular members with guide vanes 28a and diffuser elements 28b are mounted on the housing 27 of the bearing rotors.

 FIG. 6 is a side view of a casing and represents a modification of the connections in order to better use the space available around the motor, and which is particularly suitable for V-motors or installations where the motor is mounted in a tilted position. The housing is divided into two halves perpendicular to the axis of the rotor and the two housing halves are fixed to each other by means of elastic fittings 29 which preferably include metal bellows or other elastic members resistant to high temperatures. These can be so-called O-rings, or in the shape of an "E" or "U" which allow limited movement. It is also possible to use conjugated cylindrical surfaces comprising metallic annular members in the shape of an O "or" U ".

 As mentioned above, considerable advantages can be obtained by using ceramic materials, especially on the hot gas side of the system, while light metal materials such as alloys can be used on the air side. Al or Mg, or composite materials.

Different thermal movements then appear in the two halves of the casing, and these movements must be compensated for by appropriate clearances and effective gaskets and seals of an elastic nature.

 Figure 7 shows the exhaust manifold 30 of a six-cylinder engine. So that the supercharging device does not extend too loip outside and on the side of the engine block, one can advantageously use two small turbochargers 31 mounted side by side. Their exhausts are advantageously brought together in a common exhaust pipe 32, as shown in FIG. 8 which is a side view of an arrangement similar to that of FIG. 7, the intake manifold 33 being against the exhaust manifold . Considerable advantages are provided by the system described above when small turbochargers are produced in series.

 FIG. 9 shows a possible location for arranging the turbochargers 34 when it is a V-shaped engine 35. A turbocharger is preferably located outside each row of cylinders of the engine. Due to the compactness of the engine, it is possible to keep approximately the same width "B0" for a turbocharged engine or for a naturally aspirated engine.

 The turbocharger assemblies have approximately the same shape as that shown in FIG. 6. If the width "B" of the space available in the engine allows it, the exhaust and intake pipes may be of a more straight shape, and this is indicated in dashed lines on the right side of the figure. The assemblies then extend outside the engine over the distance "b" on each side.

 In the embodiments shown, the turbocharger assemblies have been fixed so that their axes of rotation are substantially vertical, which makes it possible to give them a simple shape. However, it is possible to mount the assemblies so that the axes of rotation are horizontal, in which case the manifolds connected respectively to the exhaust openings and to the intake openings are preferably connected to the opposite ends of the casing. The rotor friend can be fixed in the same way as described with reference to Figures 2 and 4.

 The embodiments where the casing extends freely from the engine block are well suited to the installation of a second exhaust gas turbine in installations where all of the energy of the exhaust gases does not is not used to compress the supply air. However, a combustion chamber can be provided to increase the extracted power.

 FIG. 10 represents an engine of the same type as that shown in FIG. 1. The exhaust and air pipes 13, 12 are connected to a casing 11 which surrounds the core of the rotor of the turbocharger (not shown). The air intake is indicated at 15 and a second exhaust gas turbine 40 having a horizontal shaft 41 is fixed to the exhaust pipe 14.

 A two-stage gear train 42 and a flywheel (not shown) connect the shaft 41 of the turbine to the power output shaft 43 of the engine, which passes through the housing 44 which partially surrounds the flywheel (not shown) of the motor. A gear or belt transmission, possibly of the variable type, can be used to transmit the excess energy of the exhaust gases to the output shaft 45.

 The power of the supercharging turbine 17 can be increased by sending fuel to the exhaust line 12. The exhaust gases usually contain a sufficient quantity of oxygen to continue to maintain a certain combustion, and at the high temperature of the gas the injected fuel gasifies and ignites quickly.

 A gaseous or liquid fuel is easily used, but it is possible to use a solid fuel, possibly in suspension in a liquid or included in a gel. The injection device can be of the usual type comprising burners and is indicated in the drawing by a pipe 46.

 It is possible in a similar manner, as a variant or in combination with the auxiliary burner described above, to send auxiliary fuel to the second exhaust gas turbine 40.

 FIG. 11 shows in more detail a combustion chamber 47 arranged in conjunction with the exhaust end of the casing 11. The combustion chamber is provided for a reverse flow, which makes it possible to obtain a flame of greater length. and facilitates the gasification of the fuel sent by means of a line 48 to a burner 49 fixed to the lower end of the combustion chamber and provided with means for forming a vortex. The combustion chamber preferably includes a conical intake diffuser which determines a reduction in the speed of the gases. The ignition is ensured by means of a candle 50, possibly in conjunction with a flame support 51.

 FIG. 12 represents a three-cylinder engine 55 comprising a supercharging device mounted in a casing 11, of the same type as described above. A box 56 contains the transmissions connected to the auxiliary devices associated with them. A second exhaust gas turbine 40 is also connected here to the exhaust pipe 14 coming from the casing 11, and it can be used to drive an electric generator or a hydraulic pump to charge an accumulator, for example of the flywheel type. 59, which is often used for hybrid power generators.

 A pipe 46 which supplies fuel to the exhaust pipe 14 is also provided. The combustion chamber 58 (see also FIG. 13) supplied with fuel by a pipe 48 is fixed to the exhaust pipe coming from the casing 11 of the turbocharger.

 The turbocharger turbine 17 and the second exhaust gas turbine 40 can be provided with guide vanes and / or an adjustable bypass device to improve the efficiency or increase the output power, or to obtain a high degree flexibility. Turbochargers of the turbine type are generally the most suitable, but it is possible to use rotors of the displacement type, for example with radial wings.

 Figure 14 shows an engine 60 of the same type as that of Figure 12 and comprising a turbocharger assembly 61, 62 and a second exhaust gas turbine 63, which are arranged so that their axes are horizontal. Whenever possible, the same references are used as those in FIG. 12.

 The shape of the turbocharger assembly appears clearly in FIG. 15. The compressor 61 and the turbine 62 which drives the latter are both of the radial type, the second being capable of receiving the gases according to a current directed inward. The second gas turbine 63 is of similar design.

 The exhaust of the turbocharger turbine 62 passes through an axial passage and a double volute 64 - see FIG. 16 - to the second gas turbine 63. The chambers 65 and 66 of the double volute are shaped so as to obtain a regular stream of gas and a natural diffuser action.

 Any one or both internal walls are provided, in the transition zone from one chamber to the other, with a lip 67 which can pivot and which makes it possible to adjust the dimension of the passage of the current.

 A combustion chamber 68 is provided in the exhaust pipe 14 upstream of the turbocharger turbine 62 to increase its power. The compressor 61 may be provided with adjustable inlet and outlet vanes 69a, b, and the two turbines 62, 63 are provided with inlet guide vanes 69d, c.

 FIG. 17 represents a development of the installation according to FIG. 15.

 The engine 70 is of the same type as described above and it is provided with an air compressor 71 which is driven by a first rotor 72 of an exhaust gas turbine. A second and a third turbine rotor 73 and 74 respectively are also provided, mounted in series downstream of the first rotor. The turbine rotors 73 and 74 are located in the same vertical plane and the transfer of gases from the first to the second takes place via a double volute 75 of the same type as that described in FIG. 16.

 A planetary gear 76 connects the shafts of the two turbine rotors 73 and 74. The output shaft 76 of the gear can be used to drive auxiliaries, or connected to the power take-off shaft 77. The motor is in additionally provided with another power draw shaft 77a indicated in dashes.

 An auxiliary shaft 78 makes it possible to transfer the power in two directions between the shaft on which the compressor 71 and the first turbine rotor 72 and the gear are mounted. A combustion chamber 79 is fixed in the exhaust pipe 13 upstream of the first turbine rotor 72. Adjustable guide vanes 80a, b, c, d are provided at the inlet of the compressor and at the entrances of all the turbine rotors.

 When the exhaust pipes, the combustion chamber and the turbines are mostly made of a ceramic material, the life of these components is important and as long as that of the engine.

Rotors mounted in air bearings do not require much maintenance.

 The ceramic materials have a specific weight which is about a third of that of steel, which makes it possible to obtain a very light assembly. Due to the high specific power that can be obtained, the installation of the motor needs only a reduced space. The volume of exhaust gas turbines is approximately half that of current installations.

 When it comes to Otto engines, a knock control device is preferably provided which detects possible variations in the internal pressure in the cylinder and actuates a valve in a bypass line. The motor can then be operated at an effective average braking pressure without having a tendency to knock.

This brings the possibility of automatic adaptation to fuels of variable octane number and / or quality.

 Water injections can also be used, and to obtain an effective melanye of the water, the latter is preferably sent by a nozzle upstream of the compressor of the turbocharger.

 Turbine rotors made of ceramic material are well suited to the use of exhaust gases obtained by combustion of a solid fuel such as pulverized coal.

 The invention is not limited to the embodiments shown, and the shape and location of the associated components can be modified in various ways while remaining within the scope of the appended claims.

Claims (10)

REVEriDICATIOWS  1. A turbocharger device for an internal combustion engine, characterized in that the pipes (12, 13) which communicate with the engine intake and exhaust openings are assembled in a single-piece casing (11), the l longitudinal axis is substantially parallel to the longitudinal median plane passing through the cylinders, and in which is mounted at least one turbine / compressor assembly (16) having an outlet and an inlet (14, 15) directed axially.  2. Turbocharger device according to claim 1, characterized in that the casing (11) comprises a cylindrical cavity (22) open completely at least at one of its ends, and in that the turbine / compressor assembly (16 ) is mounted in a cylindrical housing (20) capable of being slid into the cavity in the axial direction.  3. A turbocharger device according to claim 1, characterized in that the intake and exhaust pipes (12, 13) are assembled, each separately, in a half (25, 26) of a housing (la) which is divided in a plane perpendicular to its longitudinal axis and which comprises a cavity capable of directly receiving the rotors (25, 26) of the turbine / compressor assembly.  4. Turbocharger device according to one of claims 1 to 3, and used with a multi-cylinder engine, characterized in that the exhaust and intake manifolds (30, 33) comprise at least two turbine / compressor assemblies (31) operating in parallel.  5. A turbocharger device according to claim 4, characterized in that the exhaust system is provided with an exhaust passage (32) common to all the turbine / compressor assemblies.  6. Turbocharger device according to one of claims 1 to 5, characterized in that a second exhaust gas turbine (40) is mounted at the exhaust end of the casing (11) and comprises a shaft ( 41) connected to means (43, 47) in order to transform the residual energy contained in the gases into mechanical power.  7. A turbocharger device according to claim 6, characterized in that the shaft of the second exhaust turbine (40) is connected by means of a reduction gear (42) to the crankshaft (45) of the engine, preferably in conjunction with a steering wheel mounted on it.  8. A turbocharger device according to claim 6, characterized in that the shaft of the second exhaust turbine (40) is arranged to drive at least one of the auxiliaries (47) of the engine.  9. Turbocharger device according to one of claims 1 to 8, characterized in that it comprises means (46) for sending fuel to the exhaust pipe (12) between the engine outlet and the turbine of the turbocharger .  10. A turbocharger device according to one of claims 6 to 8, characterized in that it comprises means (48) for sending fuel to the exhaust passage between the turbine of the turbocharger and the second turbine (40).