WO2016045829A1

WO2016045829A1 - Supercharging system for an internal combustion engine and method therefor

Info

Publication number: WO2016045829A1
Application number: PCT/EP2015/067489
Authority: WO
Inventors: Gabriele Sgroi; Matthias Miller; Steffen Meyer-Salfeld; Daniel Conzelmann; Yvan Gauthier; Giovanni Cornetti
Original assignee: Robert Bosch Gmbh
Priority date: 2014-09-22
Filing date: 2015-07-30
Publication date: 2016-03-31
Also published as: DE102015204313A1

Abstract

The invention relates to a supercharging system (10) for an internal combustion engine, said supercharging system having a turbocharger (16). According to the invention, an auxiliary compressor (11) that can be driven by a hydraulic drive (12) is arranged so that it can be connected to the supercharger (16), the hydraulic drive (12), when activated, mechanically transmitting its hydraulic drive energy to the auxiliary compressor (11) by means of a hydraulic medium, in order to connect the auxiliary compressor (11) to the turbocharger (16). Preferably, the auxiliary compressor (11) is connected during the supercharging-pressure build-up phase of the supercharging system (10).

Description

title

Charging system for an internal combustion engine and method for description

The invention relates to a charging system for an internal combustion engine and a drive device, which is particularly suitable for an auxiliary compressor of such a charging system, and a method, in particular for operating such a charging system.

State of the art

In new generation diesel engines, turbocharging almost exclusively takes place. This serves on the one hand to increase the specific engine power and on the other hand to save fuel by otherwise using lost exhaust enthalpy. Unsatisfactory when charging by turbocharger, however, is their transient response, because the boost pressure typically takes about 1 to 3 seconds, because only about sufficient exhaust gas mass flow and thus turbine power boost pressure can be built. However, the exhaust gas mass flow in turn depends on the boost pressure, so that the structure of both variables is in mutually dependent relationship with each other and thus develops a relatively slow dynamics. In addition, the fuel injection amount is limited during construction, since at low boost pressure less air in the cylinders of the internal combustion engine is present and therefore also less oxygen, which is available for combustion. Accordingly, the engine power of the internal combustion engine is dimensioned during the boost pressure construction significantly lower than the stationarily achievable engine power.

From US 2003/0037546 AI a hydraulic turbine drive for a compressor for use in internal combustion engines is known. In this case, the turbine drive on a turbine wheel with turbine blades. Concentric with the turbine wheel is provided an outer ring having a plurality of nozzles formed therein for accelerating the fluid impinging on the turbine blades by a fluid medium distributed into the nozzles via an inlet channel and an inlet cavity, resulting in rotation of the turbine wheel. A disadvantage of this prior art, however, is that the turbine drive is only suitable for pressures in the range of about 1500 psi, ie in the order of about 100 bar.

Advantages of the invention

The charging system with the characterizing features of claim 1 has the advantage that the transient behavior of turbocharged internal combustion engines is significantly improved by a drivable by a hydraulic drive auxiliary compressor is assigned to the turbocharger, the hydraulic drive when actuated by a hydraulic medium its hydraulic drive energy to the auxiliary compressor mechanically mediated to the auxiliary compressor connect the turbocharger. This advantageously makes it possible to increase the torque which can be achieved transiently or else stationarily by the internal combustion engine. In addition, reduced pollutant emissions combined with low fuel consumption can be achieved by the comparatively high compression of the fresh air supplied.

The charging system according to the invention is suitable for use in particular in commercial vehicles with integrated therein hydraulic device, such as in excavators or wheel bearings or the like.

Further advantageous developments and refinements of the invention will become apparent from the measures listed in the dependent claims.

An embodiment of the invention may consist in that the additional compressor is arranged upstream of the turbocharger in the flow direction of the fresh air gases. As a result, the additional compressor works in the switched-on state as Vorverdichterstufe. Another embodiment of the invention may consist in that the additional compressor is downstream of the turbocharger in the flow direction, so that the additional compressor operates in the switched-on state as a post-compressor stage for the coming of the turbocharger air.

In order to operate the hydraulic drive for connecting the associated additional compressor, a hydraulic pump with the hydraulic drive via valve switching means can be connected. The hydraulic pump can be used when the inventive charging system in a commercial vehicle, such as an excavator or wheel loader, be the existing hydraulic pump of the commercial vehicle. For this purpose, the valve switching means may comprise at least one valve which in a

Supply line between the hydraulic pump and the hydraulic drive is arranged to lock in its blocking position the supply line to the hydraulic drive and release in its switched on passage position, the supply line. According to another embodiment of the invention, the valve switching means at least a first and a second valve, which are arranged in a supply line between the hydraulic pump and the hydraulic drive, wherein the valve switching means release the supply line to the hydraulic drive when both valves are switched to passage, whereas the Supply line is blocked when both valves are switched to the blocking position. Preference is given to the two

Valves arranged in series in the supply line. This embodiment opens up an extended range of functions, which comes into play in particular if, according to a preferred embodiment, a hydraulic accumulator is provided which can be filled with the hydraulic medium via a hydraulic pump and which can be connected to the hydraulic drive via the valve switching means.

For this purpose, the first valve in the flow direction downstream second valve in its open position connects the hydraulic accumulator via at least one line to the hydraulic drive when the first valve is switched to its blocking position. This allows the hydraulic accumulator or pressure accumulator as needed, i. if there is a transient load request, the stored one within a short time

Dispense hydraulic medium to the hydraulic drive in order to switch on or activate the additional compressor.

To fill the hydraulic accumulator during a deactivated state of the additional compressor with the hydraulic medium is, according to a further education

Provided measure that the first valve in its open position connects the hydraulic pump with the hydraulic accumulator via at least one line when the second valve is switched to its blocking position. In its locked position, the second valve ensures that the supply of hydraulic fluid to the hydraulic drive during the filling of the hydraulic accumulator is blocked. According to one embodiment of the invention, it is provided that in a line section extending between the two valves, a check valve is arranged such that a return flow of the hydraulic medium to the hydraulic pump is blocked via the first valve.

A preferred development of the invention, with which a largely automated operation of the auxiliary compressor and thus of the charging system is possible, is that a control device for detecting the operating state of the charging system and for controlling the valve switching means is provided, which is associated with the additional compressor, in dependence on detected

Operating state of the charging system to actuate the valve switching means.

According to a further development measure, a transmission can be arranged between the additional compressor and the hydraulic drive in order to convey the drive energy of the hydraulic drive to the auxiliary compressor. A transmission is only required if the speeds of the hydraulic drive and the associated additional compressor differ from each other.

According to one development of the invention, the hydraulic drive may comprise a turbine and at least one injector which are arranged relative to one another such that a jet of the hydraulic medium which can be generated by the injector detects at least one turbine active element of the turbine in order to drive the turbine. By combining an injector with a hydraulic turbine, a high pressure range on the order of a few kbar can be achieved with fast cycle times due to the characteristics of the injector. A

Embodiment may consist in that the hydraulic drive comprises a Pelton turbine, wherein the turbine active elements are formed as arranged on a circumference of a turbine blades blades and the injector generated by the beam is directed approximately tangentially to the circumference of the turbine wheel to sequentially detect the blades. This is faster

Speed build-up in a hydraulic drive formed by an injector and a Pelton turbine possible because the Pelton turbine has a low moment of inertia in relation to the turbine power. According to another embodiment, the hydraulic drive may comprise a Tesla turbine, wherein the turbine NEN active elements are arranged as arranged on a turbine axis of a turbine wheel and axially spaced apart from each other by slots discs and the jet, which can be generated by the injector, is directed approximately parallel to the surface of at least one of the disks on an outer edge of the disks. By combining an injector with a Tesla turbine again significantly higher speeds can be achieved in a hydraulic drive formed thereby.

An advantageous embodiment of the invention may be that is provided as the hydraulic medium for operating the hydraulic drive diesel fuel. As a result, instead of a hydraulic pump for supplying the hydraulic medium, a diesel high-pressure pump which is present in any case on a diesel internal combustion engine as standard can be used in a cost-saving manner.

According to an advantageous embodiment of the invention, the additional compressor may be designed as a positive displacement. Since positive displacement superchargers are typically characterized by a relatively low drive speed level of about 5,000 to 10,000 revolutions per minute, the hydraulic drive for the

Conveniently, additional compressors are selected from a wide variety of different and available series hydraulic motor types, including, for example, axial piston, radial piston, external gear, internal gear or vane motors.

If, according to one embodiment of the invention, the additional compressor is designed as a volumetric compressor, preferably as a spiral charger or G-charger, then a fast response can also be achieved for a specially designed additional compressor, especially at relatively low speeds, since spiral-wound or G-type superchargers are used. Chargers belong to the group of displacement loaders. According to a further embodiment of the invention, the additional compressor can be realized as a screw compressor or Roots compressor, since such compressors also belong to the group of displacement loaders and thus achieve a relatively high efficiency at low speeds.

A drive device, which is particularly suitable for an auxiliary compressor of such a charging system, has a turbine with turbine reaction elements for absorbing the kinetic energy of a fluid. In this case, according to the invention, at least one injector is provided, which is arranged in such a way to the turbine that a jet of the fluid, which can be generated by the injector, of at least one of the

Turbine elements detected to drive the turbine. In contrast to The prior art according to US 2003/0037546 AI is achieved by combining an injector with a hydraulic turbine, a significantly higher pressure range up to the order of about 3000 bar at very fast cycle times, as with an injector due to its characteristics rapid opening and closing possible is. As a result, the inventive

Drive device particularly suitable as a hydraulic drive for an additional compressor.

An embodiment of the drive device may consist in that the turbine is designed as a Pelton turbine, wherein the turbine active elements are formed as arranged on a circumference of a turbine blades blades and the injector generated by the beam is directed approximately tangentially to the circumference of the turbine wheel to successively to detect the blades. Since the Pelton turbine typically has an extremely low moment of inertia in relation to the achievable performance, in combination with the characteristic properties of the injector, a fast speed build-up in the drive device is possible.

Another embodiment of the drive device may consist in that the turbine is designed as a Tesla turbine, wherein the turbine active elements are arranged as arranged on a turbine axis of a turbine wheel and axially spaced from each other by slots discs and the injector generated by the beam about parallel to the surface of at least one the discs is directed to an outer edge of the discs. By combining an injector with a Tesla turbine, very high speeds are advantageous

Compared to the technically usable speed range of a Pelton turbine achievable. In addition, even at low rotational speeds in the vicinity of the turbine standstill still a relatively high torque can be achieved. The inventive method is used in particular for operating the

Charging system and includes the following steps of detecting the current operating condition, in particular the boost pressure of the charging system, the activation of the auxiliary compressor depending on the detected operating state of the charging system, wherein the auxiliary compressor associated hydraulic raulikantrieb is actuated by supplying a hydraulic medium, and

Deactivating the auxiliary compressor when reaching or exceeding a certain boost pressure levels in the charging system, wherein the hydraulic drive is shut off by shutting off the supply of hydraulic medium to the hydraulic drive. The auxiliary compressor is preferably activated during the boost pressure buildup phase of the supercharging system.

A variant of the method may consist in enabling a passage from a hydraulic pump to the hydraulic drive to activate the auxiliary compressor. The then flowing from the hydraulic pump to the hydraulic drive hydraulic medium sets the hydraulic drive in motion, which in turn carries the coupled additional compressor. The auxiliary compressor activated thereby compresses the incoming fresh air and thus supports the turbocharger when building up the boost pressure.

According to an alternative variant of the method, a passage from a hydraulic accumulator containing the hydraulic medium to the hydraulic drive is released to activate the additional compressor.

An advantageous and expedient development of the method according to the invention is that in the deactivated state of the additional compressor of the hydraulic accumulator is filled with the hydraulic medium by a passage from the hydraulic pump is released to the hydraulic accumulator.

drawings

Embodiments of the invention are explained in more detail in the following description and in the accompanying drawings. The latter show in strongly schematic views:

1 is a diagram of an additional compressor with a hydraulic drive and a transmission arranged therebetween,

2 is a schematic of a first embodiment of a supercharging system for an internal combustion engine, wherein the supercharging system includes an air cleaner, a turbocharger, a charge air cooler, a throttle, an engine block having a plurality of cylinders, wherein the supercharger is upstream with an associated control unit upstream of the turbocharger, 3 shows a diagram of a second embodiment of the supercharging system, wherein the additional compressor with the associated control unit downstream of the turbocharger,

Fig. 4 is a schematic representation of a first embodiment of a circuit arrangement for the hydraulic drive and the auxiliary compressor with a hydraulic pump and a directional control valve, the directional control valve in a first position blocks a connecting line between the hydraulic pump and the hydraulic drive and releases the connecting line in a second position .

5 is a schematic representation of a second embodiment of the circuit arrangement for the hydraulic drive and the additional compressor,

6 is a diagram of a hydraulic drive formed from a Pelton turbine and a Magnetinjektor,

7 is a cross-sectional view of the booster compressor together with the hydraulic drive formed by Magnetinjektor and Pelton turbine of FIG. 6,

8 is a partially sectioned view of the hydraulic drive of Fig. 7,

9 shows a flow chart with the essential method steps of a first embodiment variant of a method for operating the charging system, and

10 shows a flow chart with the essential method steps of a second variant of the method for operating the charging system.

Description of the embodiments

Fig. 1 shows schematically a section of an inventive

Charging system 10 for an internal combustion engine, wherein the charging system 10 is an additional compressor 11, a hydraulic drive 12 for the auxiliary compressor 11th and a arranged between additional compressor 11 and hydraulic drive 12 transmission 13 has. The auxiliary compressor 11 comprises a compressor housing 11 ^' and a compressor wheel 11 ^" received therein, which is driven by the hydraulic drive 12 via the intermediate gear 13 to suck in fresh air according to arrow 14, to compress and then the compressed air according to

Arrow 15 a - not shown in the figure - to supply turbocharger. The hydraulic drive 12 associated with the auxiliary compressor is preferably designed as a hydraulic motor, for example as an axial piston motor, external gear motor or vane motor, and is operated with a hydraulic medium, which is supplied via a first hydraulic connection 12 ^' and can flow away again via a second hydraulic connection 12 ^" Alternatively, the transmission can be designed as a friction gear The auxiliary compressor 11 serves to support a turbocharger, especially during transient processes, in that the additional compressor compresses air, as long as the turbocharger For this purpose, the additional compressor can be designed as a radial compressor Alternatively, the additional compressor can be used advantageously as a volumetric compressor, eg as a spiral loader a be educated; In this case, an intermediate gear is dispensable, since the additional compressor and the hydraulic drive operate in the same speed range. Spiral loaders are - as is known in the art - the group of

Supercharger. Fig. 2 schematically illustrates a first embodiment of the

Charging System 10. The charging system 10 includes a turbocharger 16 having its compressor side 16 ^'received in an intake branch 17 of the charging system 10. On the other hand, the turbine side 16 ^"of the turbocharger 16 is accommodated in an exhaust branch 18, with the compressor side 16 ^' and the turbine side 16 ^{" being} connected via a shaft 16 ^"' In the intake branch 17 is a charge air cooler 19 downstream of the compressor side 16 ^'of the turbocharger 16 is arranged to cool down the air compressed by the turbocharger, which then passes into the engine 21 via a throttle valve 20 located downstream of the charge air cooler 19. From the engine 21, the exhaust gas flows into the exhaust branch 18. Part of the exhaust gases becomes via an exhaust gas recirculation line 18 ^' , in which an exhaust gas cooler 22 with downstream Exhaust gas recirculation valve 22 ^'is arranged, branched off and fed back to the input of the internal combustion engine 21. Optionally, a secondary line 27 is provided, which is arranged parallel to the exhaust gas cooler 22, wherein in the secondary line 27, a valve 27 ^{'is received on the} input side, with which the secondary line 27 can be opened or blocked. The majority of the exhaust gases passes in the exhaust branch 18 to the turbine side 16 ^"of the turbocharger 16, wherein a parallel to the turbine side 16 ^" extending Wastegate- line can be opened or closed by means of a wastegate valve 23 received therein input side. The exhaust gases flowing through the turbine side 16 ^" drive the compressor side 16 ^'of the turbocharger 16 via the shaft 16 ^"' . In the intake branch 17 of the additional compressor 11 is provided, which is upstream of the compressor side 16 ^'of the turbocharger 16, so seen in the flow direction of the fresh air arranged in front of this, the additional compressor 11 is driven by means of - not shown in Fig. 2 - hydraulic drive. Upstream of the additional compressor 11, an air filter 24 is arranged on the intake side in the intake branch 17.

The fresh air flowing through the air filter 24 passes on the one hand to the additional compressor 11 and on the other hand to a parallel to the auxiliary compressor 11 extending bypass line 25 in which a bypass valve 25 ^' is added. The charging system 10 is now controlled so that the auxiliary compressor 11 is operated during the supercharger pressure build-up, wherein the bypass valve 25 ^' in his

Locking position is switched and thereby blocks the bypass line 25 and after reaching a predetermined charge pressure of the additional compressor 11 is switched off again, wherein the bypass valve 25 ^{'is switched} to its open position in which the bypass line 25 is opened and thereby from the air filter 24th incoming fresh air is deflected around the additional compressor 11 to avoid flow losses due to throttle effects. For the sake of clarity, the element denoted by reference numeral 11 in FIG. 2 comprises not only the auxiliary compressor but also the associated hydraulic drive and, if necessary, an intermediate transmission. In this case, hydraulic connections 11-1 and 11-2 are provided for the supply and removal of a hydraulic medium, which connect the hydraulic drive of the additional compressor with a hydraulic pump. For controlling the auxiliary compressor 11 and the associated hydraulic drive, a control device 26 is provided which is connected electronically via an electrical signal line 26 ^' to the auxiliary compressor and the hydraulic drive via valve switching means (to be explained below). In addition, the controller 26 is electronically on Sensors connected to the respective current operating condition of the internal combustion engine 21 and the charging system 10, in particular to detect the boost pressure.

3 schematically illustrates the charging system 10 according to a second embodiment, which differs from the first embodiment shown in FIG. 2 essentially in that the additional compressor 11 is arranged downstream of the compressor side 16 ^'of the turbocharger 16 in the intake branch 17, as viewed in the direction of flow of the fresh air is. With regard to the remaining details of the embodiment of Fig. 3, reference is made to the comments on the embodiment of Fig. 2. In FIG. 3, the same reference numerals designate the same or similar elements as in FIG. 2. For the sake of clarity, the element designated by reference numeral 11 in FIG. 3 includes not only the auxiliary compressor but also the associated hydraulic drive and, if required, one intermediate gearbox. The turbocharger 16 is arranged with its compressor side 16 ^'seen in the flow direction of the fresh air downstream of the air filter 24 in the intake branch 17. The intercooler 19 is arranged immediately behind the compressor side 16 ^'of the turbocharger. The charge air cooler 19 is seen in the flow direction of the fresh air, the additional compressor 11 with the parallel thereto bypass line 25 downstream, in which the bypass valve 25 ^' is added. After the additional compressor 11, the throttle valve 20 is arranged in front of the input side of the internal combustion engine 21. In this second embodiment, the additional compressor 11 thus operates in post-compression function. To control the auxiliary compressor 11 and the associated hydraulic drive and the other components of the

Charging system according to the second embodiment is the control device 26, which in this case performs substantially the same functions as in the first embodiment. Thus, when the auxiliary compressor 11 is deactivated, the control device 26 opens the bypass valve 25 ^' in order to guide the incoming air via the bypass line 25 about the additional compressor 11 in order to avoid flow losses.

The charging system according to the invention is not only suitable for wastegate configurations, but also for other configurations such as variable turbine geometries. Fig. 4 shows very schematically an embodiment of a circuit arrangement of a hydraulic part of the charging system according to the invention. In this case, the auxiliary compressor 11 is associated with a hydraulic drive 12, which drives the auxiliary compressor 11. In order to supply the hydraulic drive 12 with a hydraulic medium, for example oil, a hydraulic pump 30 is provided, which is connected to the suction side of a tank 34 with the hydraulic medium and can be designed, for example, as a gear or axial piston pump with a fixed or variable displacement volume , A valve 31, which is designed as a multi-way valve and is controllable by the control device 26, not shown in FIG. 4, is received in a hydraulic supply line 32 which leads from the hydraulic pump 30 to the hydraulic drive 12. In its first position, the valve 31 shuts off the passage from the hydraulic pump 30 to the hydraulic drive 12 by the valve 31 connecting a line section of the supply line 32 extending between the hydraulic pump 30 and the valve 31 to a line 33 leading from the valve 31 to the tank 34 leads. As a result, in this position of the valve 31, the hydraulic medium coming from the hydraulic pump returns to the tank 34. In its second position, the valve 31 releases a passage from the hydraulic pump 30 to the hydraulic drive 12 by the valve 31 extending between the hydraulic pump 30 and the valve 31 extending line section of the supply line 32 separates from the line 33 and instead connects this line section with a running between the valve 31 and the hydraulic drive line section of the supply line 32. Via the passage thus produced, the hydraulic pump 30 can supply the hydraulic drive 12 with the hydraulic medium. The control of the valve 31 by means of the control device 26 in this case so that the valve 31 is switched only during the active operation of the auxiliary compressor 11 in its second position in which the passage from the hydraulic pump 30 to the hydraulic drive 12 is released, and during the deactivated state of the additional compressor 11 in its first position, ie blocking position, remains switched.

FIG. 5 shows a highly diagrammatic view of a modified embodiment of a circuit arrangement of the hydraulic part of the charging system according to the invention, as compared to FIG. 4. This modification differs from the variant illustrated in FIG. 4 essentially in that, instead of the valve 31 (FIG. 4), a valve block 40 with additional functions is provided in order to by means of a hydraulic accumulator or pressure accumulator 49 to be able to supply the hydraulic drive 12 with the hydraulic medium during the active phase of the auxiliary compressor 11. For this purpose, the valve block 40 comprises two valves 41, 42, which are designed as electrically controllable directional valves, in the preferred embodiment as a solenoid valves, and also a pressure sensor 43, a

Here, in Fig. 5, like reference numerals designate the same or similar elements or components as in Fig. 4. The valves 41, 42 are in the leading from the hydraulic pump 30 to the hydraulic drive 12 hydraulic supply line 32 in flow direction - seen consecutively, ie taken in series.

In its first position, the first valve 41 blocks the passage from the hydraulic pump 30 to the second valve 42 and thus to the hydraulic drive 12, by the valve 41 having a first line section of the supply line 32 extending between the hydraulic pump 30 and the first valve 41 with a line 33 connects, which leads from the first valve 41 to the tank 34. In its second position, the first valve 41 opens a passage to the second valve 42, in which the first valve 41 connects the first line section of the supply line 32 with its second line section, which extends between the first valve 41 and the second valve 42. If in this case the second valve 42 is in its first position, that is to say in its blocking position, then the passage is to the hydraulic drive

12 shut off. Due to the open position of the first valve 41 and the blocking position of the second valve 42, however, a passage to the hydraulic accumulator 49 is released because a branched off from the second line section of the feed line 32 line 46 is connected to a line 47, which leads to the hydraulic accumulator 49. As a result, 40 in this switching state of the valve block

Hydraulic pump 30 fill the hydraulic accumulator 49 with the hydraulic medium. In its second position, when the first valve 41 is in the open position, the valve 42 releases the passage from the hydraulic pump 30 to the hydraulic drive 12 by connecting the second line section of the supply line to a third line section located between the second valve 42 and the hydraulic drive 12 extends. In the open position of the second valve 42 and in the blocking position of the first valve 41, however, the hydraulic accumulator 49 can supply the hydraulic drive 12 with the hydraulic medium, since the lines 46 and 47 are connected via the open second valve 42 to the third line section of the supply line 32. The pressure limiting valve 44 is received in the line 47 and thereby serves to secure the maximum permissible pressure for the hydro- memory 49 and the hydraulic drive 12. The coupled to the line 47 pressure sensor 43 is used for pressure detection in the lines 46 and 47 and transmits the corresponding measurement data to the - not shown - control device 26; upon reaching a predetermined pressure threshold, the pressure relief valve 44 is activated, which then opens to relieve the hydraulic accumulator 49 and remove from the hydraulic accumulator 49 a certain amount of hydraulic medium to the tank 34 via line 47 until the pressure falls below the predetermined pressure threshold. The check valve 45 accommodated between the two valves 41, 42 in the second line section of the supply line 32 is upstream of the line 46 in the conveying direction and thereby prevents backflow of the hydraulic medium to the hydraulic pump 30. The control or interaction of the individual elements or components in FIG 5 takes place by means of the control device 26 (not shown in FIG. 5) in such a way that the hydraulic accumulator 49 is filled when the hydraulic drive 12 can provide sufficient or excess power for the operation of the auxiliary compressor 11. The discharge of the hydraulic accumulator 49, however, takes place when a transient load is to be delivered to the auxiliary compressor 11.

6 shows a sectional view of a realization of the hydraulic drive, which is particularly suitable for driving the auxiliary compressor 11 and is formed by an injector 50 and a Pelton turbine 51. Such an injector is commonly used in diesel engines to inject fuel into the engine's combustion space, while a Pelton turbine is typically used in hydroelectric power plants for power generation by converting the pressure and velocity energy of water in the Pelton turbine into rotational energy is then converted by a generator into electrical energy. In the arrangement according to the invention, the injector 50 and the Pelton turbine 51 are positioned to each other so that the outlet-side injector facing the Pelton turbine 51 and the

Injektorlängsachse 50 ^" , along which extends a Injektordruckkammer, approximately tangent to the circumference of the Pelton turbine 51 is aligned so that a generated by the injector 50 and at the injector via a received there injector needle exiting fluid jet 50 ^' a respective top and Fluid jet 50 ^' facing turbine blade 52 of the turbine 51 detects and thereby set the blade assembly of the turbine 51 to the turbine rotation axis 53 in motion. For this purpose, the fluid, which may be, for example, water, diesel fuel, hydraulic oil or the like, fed under high pressure into the injector and greatly accelerated at the outlet side or injection port side injector under pressure release, the fluid jet 50 ^'is formed, which then successively impinges on the blades 52 arranged on the circumference of the turbine. The injector 50 fulfills the one hand, the function of the beam formation and on the other hand, a valve function of turning on and off the turbine and thus the hydraulic drive. By virtue of its characteristic properties, the injector 50 can open and close relatively quickly, so that high dynamics can be achieved during switching on and off operations of the Pelton turbine 51. Furthermore, by clocked control of the injector 50 average loads can be generated because with injectors of the newer generation very high pressures in the pressure range up to 3 kbar and very fast cycle times can be achieved. Since the Pelton turbine 51 typically has an extremely low moment of inertia relative to its power, along with the characteristic injector characteristics, rapid speed build-up in the turbine 51 is possible, which aids in dynamic processes. An increase in efficiency of the inventive arrangement of injector 50 and Pelton turbine 51 can be achieved by a negative pressure is generated in the turbine chamber, as there are lower losses in the turbine 51 due to undesirable braking of the fluid jet in air.

FIG. 7 shows in a view analogous to FIG. 1 the additional compressor 11 together with an embodiment of the hydraulic drive 12 as part of the charging system according to the invention, wherein the hydraulic drive 12 for the auxiliary compressor 11 by the arrangement comprising the injector 50 and the Pelton turbine 51 Fig. 6 is realized. Advantageously, results from the inventive combination of an injector 50 with a Pelton turbine 51 taking advantage of the low moment of inertia of the Pelton turbine 51 and the rapid beam formation by means of the injector 50, a fast response of the auxiliary compressor, causing high speeds of the Pelton turbine and thus the Hydraulic drive 12 are possible, so that a transmission between additional compressor 11 and hydraulic drive 12 is dispensable.

FIG. 8 illustrates the hydraulic drive of FIG. 7, wherein a first hydraulic connection 12 ^' serves to supply the hydraulic fluid and to the injector while a second hydraulic port 12 ^" serves to recirculate the hydraulic fluid and is provided end to a return line 54 of the Pelton turbine 51. A modified embodiment of the arrangement of Figures 7 and 8 is that a turbine is a Tesla turbine For this purpose, the injector is arranged with respect to the Tesla turbine such that a fluid jet generated at its exit-side injector end faces an inlet at the outer edge of and axially spaced from each other on a turbine axis of the Tesla turbine As they pass through the slots, the fluid jet generated by the injector transfers its kinetic energy to the respective surfaces of the discs, whereby the latter are known per se Wirkprinzi p the Tesla turbine in a rotational movement about its rotation or

Turbine axis are offset. The progressively decelerated fluid jet eventually exits the Tesla turbine via an outlet near the axis of rotation. Advantageously, very high speeds compared to the technically usable speed range when using a Pelton turbine can be achieved by the inventive combination of an injector with a Tesla turbine. As a result, a hydraulic drive formed by such a combination is suitable for a naturally occurring additional high-speed compressor. FIG. 9 shows a flowchart, generally designated by 100, showing the essential method steps of a first embodiment of the method according to the invention, which is implemented in the control device 26 and is used to operate the charging system 10, i. the interaction of the individual components of the charging system is used. The first embodiment of the method corresponds to the circuit arrangement of FIG. 4. In a first method step 110, the current operating state of the charging system 10, in particular the charging pressure, is continuously recorded and evaluated or analyzed by means of the control device 26. If the control device 26 recognizes on the basis of the recorded and evaluated measurement data that there is a boost pressure build-up phase, then in an adjoining process step

120 the additional compressor 11 is activated or switched on by the control The control device 26 controls electrically the valve switching means 31, whereupon the passage from the hydraulic pump 30 to the hydraulic drive 12 for the hydraulic fluid via the supply line 32 is released. The hydraulic medium flowing to the hydraulic drive 12 then sets the hydraulic drive 12 in

Gang, which in turn drives the auxiliary compressor 11. In a further method step 130, the control device 26 continuously checks whether a predetermined charge pressure has been reached. For this purpose, a comparison of the continuously detected boost pressure measurement data with the predetermined boost pressure level is performed. If this comparison step 130 reveals that the predetermined boost pressure level has been reached or even exceeded, the deactivation or deactivation of the auxiliary compressor 11 takes place in an immediately following method step 140 in that the control device 26 controls the valve switching means 31 in such a way that the passage from the hydraulic pump 30 is shut off to the hydraulic drive 12 for the hydraulic fluid, whereupon the hydraulic drive 12 and thus the

Switch off additional compressor 11. Subsequently, there is a return to step 110. If, however, the comparison step 130 that the predetermined boost pressure level has not yet been reached, while the line for the operation of the auxiliary compressor 11 is kept open until - waited until the predetermined boost pressure level is reached.

The predetermined boost pressure level can be calculated according to an embodiment in dependence on the fresh air or gas mass flow through the additional compressor, the gas inlet temperature detected upstream of the auxiliary compressor and the gas pressure detected upstream of the auxiliary compressor in order to reach the additional compressor when it reaches its stuffing limit or Its maximum design of its volume flow or its maximum allowable speed can be switched off. In such a case, the predetermined boost pressure level is determined as a dynamic quantity.

10 is a flowchart, generally designated 200, showing the essential steps of a second embodiment of the method of the invention implemented in the controller 26 and used to operate the charging system 10, i. the interaction of the individual

Components of the charging system is used. The second embodiment of the invention In a first method step 210, the current operating state of the charging system, in particular the boost pressure by means of a pressure sensor, which is arranged in the intake branch between the bypass and the engine, continuously recorded and evaluated or analyzed by means of the control device 26 , If the control device 26 recognizes on the basis of the recorded and evaluated measurement data that there is a boost pressure build-up phase, the auxiliary compressor 11 is activated or switched on in a subsequent process step 220; In this case, the control device 26 first checks whether the hydraulic accumulator 49 is sufficiently filled with the hydraulic medium; if the result is positive

Test controls the controller 26, the valves 41, 42 of the valve block 40 so that the first valve in its blocking position and the second valve 42 switches to its open position, whereby a passage from the hydraulic accumulator 49 is released to the hydraulic drive 12. If the result of the test is negative, i. if the hydraulic accumulator is not sufficiently filled or empty, the

Activating the valves 41, 42 such that both the first valve 41 and the second valve 42 switch to open or open position, so that a passage from the hydraulic pump to the hydraulic drive is released; at the same time by the control device - not shown in Figure 5 - valve, which is preferably part of the hydraulic accumulator or the hydraulic accumulator, e.g. in

Line 46, may be upstream, connected in blocking position to fluidly decouple the hydraulic accumulator from the unlocked passage. In both cases, the hydraulic fluid then flows to the hydraulic drive 12, whereupon the hydraulic drive 12 starts and drives the auxiliary compressor 11. In a further method step 230, the control device 26 continuously checks whether a predetermined charge pressure has been reached. For this purpose, a comparison of the continuously detected boost pressure measurement data with the predetermined boost pressure level is performed. If this comparison step 230 reveals that the predetermined charge pressure level has been reached or even exceeded, the deactivation or deactivation of the additional compressor takes place in an immediately following method step 240

11, in that the control device 26 controls the valves 41, 42 of the valve block 40 in such a way that the passage for the hydraulic medium to the hydraulic drive 12 is shut off, whereupon the hydraulic drive 12 and therefore the additional compressor 11 are switched off. In a following step 250, the hydraulic accumulator 49 is filled by the controller 26 holding the first valve 41 open and the second

Valve 42 blocks and optionally the - not shown in Fig. 5 - valve of Hydraulic accumulator switches in the open position. Subsequently, a return to step 210 takes place. If, however, the comparison step 230 reveals that the predetermined charge pressure level has not yet been reached, then while the line is kept open for the operation of the auxiliary compressor, it is waited until the predetermined charge pressure level is reached.

In summary, in a supercharging system 10 with a turbocharger for an internal combustion engine, an auxiliary compressor 11 that can be driven by a hydraulic drive 12 is assigned to the turbocharger 16, wherein the hydraulic drive 12 mechanically mediates its hydraulic drive energy to the auxiliary compressor 11 when actuated by means of a hydraulic medium Additional compressor 11 turn on the turbocharger 16. A control device 26 is used to detect the operating state of

Charging system 10 and for controlling the valve switching means 31 and 40, 41, 42, wherein the control device 26 is associated with the additional compressor 11 and the hydraulic drive 12 to operate in response to the detected operating state of the charging system 10, the valve switching means. For switching on or activating the auxiliary compressor 11, a passage from the hydraulic pump 30 to the hydraulic drive or a passage from the hydraulic medium-containing hydraulic accumulator 49 to the hydraulic drive is released by means of the valve switching means. The auxiliary compressor 11 is preferably activated during the boost pressure buildup phase of the charging system 10.

Claims

claims

Charging system for an internal combustion engine, wherein the supercharging system has a turbocharger, characterized in that one of a hydraulic drive (12) drivable additional compressor (11) the turbocharger (16) is assigned switchable, wherein the hydraulic drive (12) when actuated by means of a hydraulic medium its hydraulic drive energy to the auxiliary compressor (11) mechanically mediated to the auxiliary compressor (11) the turbocharger (16) zuzuschalten.

2. Charging system according to claim 1, characterized in that the additional compressor (11) in the flow direction of the turbocharger (16) is arranged upstream.

3. Charging system according to claim 1, characterized in that the additional compressor (11) downstream of the turbocharger (16) is arranged in the flow direction.

4. Charging system according to one of claims 1 to 3, characterized in that via valve switching means (30; 40, 41, 42), a hydraulic pump (30) with the hydraulic drive (12) is connectable.

5. Charging system according to one of claims 1 to 4, characterized in that the valve switching means comprise at least one valve (30) which is arranged in a feed line (32) between the hydraulic pump (30) and the hydraulic drive (12) in order to Blocked position to block the supply line (32) to the hydraulic drive (12) and release in its switched on passage position the supply line (32).

6. Charging system according to one of claims 1 to 4, characterized in that the valve switching means comprise at least a first and a second valve (41, 42) in a supply line (32) between the hydraulic pump (30) and the hydraulic drive (12). are arranged, wherein the valve switching means (41, 42) the supply line (32) to the hydraulic drive (12) release when both valves (41, 42) are switched to passage, whereas the supply line (32) is locked when both valves (42 , 42) are switched in blocking position.

7. Charging system according to claim 6, characterized in that a hydraulic accumulator (49) is provided which can be filled via a hydraulic pump (30) and which can be connected via valve switching means (41, 42) to the hydraulic drive (12).

8. Charging system according to claim 7, characterized in that the first valve (41) in the flow direction downstream second valve (42) in its open position the hydraulic accumulator (49) via at least one line (46, 47) connects to the hydraulic drive (12) when the first valve (41) is switched to its blocking position.

9. Charging system according to claim 7 or 8, characterized in that the first valve (41) in its open position, the hydraulic pump (30) with the hydraulic accumulator (49) via at least one line (46, 47) connects when the second valve (42 ) is switched to its blocking position.

10. Charging system according to one of claims 6 to 9, characterized in that in a between two valves (41, 42) extending line portion, a check valve (45) is arranged such that a return flow of the hydraulic medium to the hydraulic pump (30) through the first Valve (41) is blocked.

Charging system according to one of Claims 4 to 10, characterized in that a control device (26) is provided for detecting the operating state of the charging system (10) and for controlling the valve switching means associated with the auxiliary compressor (11) in dependence on detected operating state of the charging system to actuate the valve switching means.

12. Charging system according to one of claims 1 to 11, characterized in that a transmission (13) between the auxiliary compressor (11) and the hydraulic drive (12) is arranged to impart the driving energy of the hydraulic drive (12) to the additional compressor (11) ,

13. Charging system according to one of claims 1 to 12, characterized in that the hydraulic drive (12) comprises a turbine (51) and at least one injector (50), which are arranged to each other such that one of Injek- tor (50) producible jet (50 ^' ) of the hydraulic medium detects at least one turbine acting element (52) of the turbine (51) to drive the turbine.

14. A charging system according to claim 13, characterized in that the hydraulic drive (12) comprises a Pelton turbine, wherein the turbine active elements (52) are formed as arranged on a circumference of a turbine blades blades and the jet generated by the injector approximately tangential to the circumference of Turbine is directed to sequentially detect the blades.

15. Charging system according to claim 13, characterized in that the hydraulic drive (12) comprises a Tesla turbine, wherein the turbine active elements are arranged as arranged on a turbine axis of a turbine wheel and axially spaced apart from each other by slots discs and the jet can be generated by the injector approximately parallel to Surface of at least one of the discs is directed to an outer edge of the discs.

16. Charging system according to one of claims 1 to 15, characterized in that the hydraulic medium is designed to operate the hydraulic drive as a diesel fuel.

17. Charging system according to one of claims 1 to 16, characterized in that the additional compressor (11) is designed as a positive displacement.

18. Charging system according to claim 17, characterized in that the additional compressor (11) is designed as a volumetric compressor, preferably as a spiral loader.

19. Charging system according to claim 17, characterized in that the additional compressor (11) is designed as a screw compressor.

20. Drive device in particular for an additional compressor of a

Charging system, wherein the drive device comprises a turbine (51) with turbine operating elements (52) for receiving the kinetic energy of an impinging fluid, characterized in that at least one injector (50) is provided, which is arranged in such a way to the turbine (51), that one of the jector (50) producible beam (50 ^') of the fluid for sensing at least one of the turbine operating elements (52) to drive the turbine (51).

21. Drive device according to claim 20, characterized in that the turbine (51) is designed as a Pelton turbine, wherein the turbine active elements (52) are formed as arranged on a circumference of a turbine blades blades and the injector (50) producible jet (50 ^' ) is directed approximately tangentially to the circumference of the turbine wheel to sequentially detect the blades.

22. Drive device according to claim 20, characterized in that the turbine (51) is designed as a Tesla turbine, wherein the turbine active elements are arranged as arranged on a turbine axis of a turbine wheel and axially spaced apart from each other by slots discs and the injector (50) producible Beam (50 ^' ) is directed approximately parallel to the surface of at least one of the discs on an outer edge of the discs.

23. A method in particular for operating the charging system according to one of claims 1 to 16 with the following method steps:

- detecting (110; 210) the current operating state, in particular the charging pressure of the charging system;

Activating (120; 220) the auxiliary compressor as a function of the detected operating state of the charging system, wherein the hydraulic drive assigned to the auxiliary compressor is actuated by supplying a hydraulic medium,

- deactivating (140; 240) the auxiliary compressor when reaching or exceeding a predetermined boost pressure level in the charging system, wherein the hydraulic drive is shut off by shutting off the supply of the hydraulic medium.

24. The method according to claim 23, characterized in that the additional compressor is activated during the boost pressure build-up phase of the charging system.

25. The method according to claim 23 or 24, characterized in that for activating the additional compressor, a passage from a hydraulic pump is released to the hydraulic drive.

26. The method of claim 23 or 24, characterized in that for activating the auxiliary compressor, a passage of a hydraulic medium containing the hydraulic accumulator (49) is released to the hydraulic drive.

27. The method according to claim 26, characterized in that in the deactivated state of the additional compressor of the hydraulic accumulator (49) is filled with the hydraulic medium (250) by a passage from the hydraulic pump to the hydraulic accumulator (49) is released.