EP2681428A1

EP2681428A1 - Turbo-compound system, in particular of a motor vehicle

Info

Publication number: EP2681428A1
Application number: EP12705072.2A
Authority: EP
Inventors: Markus Kley
Original assignee: Voith Patent GmbH
Current assignee: Voith Patent GmbH
Priority date: 2011-03-02
Filing date: 2012-02-18
Publication date: 2014-01-08
Also published as: JP2014511455A; CN103189617A; US20140075935A1; WO2012116787A1; DE102011012861A1; BR112013019759A2

Abstract

The invention relates to a turbo-compound system, in particular of a motor vehicle having an internal combustion engine which has an output shaft; having an exhaust-gas power turbine which is arranged in the exhaust-gas flow of the internal combustion engine and has an impeller wheel which is mounted fixedly on a turbine shaft so as to rotate with it; the exhaust-gas power turbine is drive-connected via a step-up gear mechanism to the output shaft of the internal combustion engine, in order to transmit drive power via the step-up gear mechanism to the output shaft; having a hydrodynamic coupling which has an impeller and a turbine wheel which form, with one another, a toroidal working chamber which can be filled with working medium via an inlet, in order to transmit torque hydrodynamically from the impeller to the turbine wheel; wherein at least one gearwheel of the step-up gear mechanism is lubricated with working medium of the hydrodynamic coupling, and the step-up gear mechanism is arranged in the drive connection between the hydrodynamic coupling and the exhaust-gas power turbine. The invention is characterized in that the step-up gear mechanism is configured as a planetary gear mechanism, comprising a sun gear, at least one planetary gear, which is mounted on a planetary carrier, and an internal gear which are in engagement with one another; and a lubricant channel is arranged in the planetary carrier in order to lubricate at least the sun gear, internal gear and/or at least one planetary gear with working medium.

Description

Turbo-compound system, in particular of a motor vehicle

The present invention relates to a turbo-compound system, that is to say a system in a drive train, in particular of a motor vehicle, having an internal combustion engine for driving the drive train, in the exhaust gas flow of which an exhaust gas utilization turbine is arranged. The exhaust gas turbine can, for example, be arranged in the exhaust gas stream in front of or behind the exhaust gas turbine of an exhaust gas turbocharger. By means of the exhaust gas turbine, the exhaust gas of the internal combustion engine is deprived of energy and converted into mechanical energy or drive power. This then serves the additional drive of the output shaft of the engine, usually the crankshaft. Such turbo-compound systems are known. Thus, EP 0 751 027 Bl describes the arrangement of a hydrodynamic coupling in such a turbo-compound system in order to transfer the energy obtained from the exhaust gas of the internal combustion engine from an exhaust gas turbine to the crankshaft. To this end, the hydrodynamic coupling comprises an impeller and a turbine wheel, which form a working space which can be filled with working fluid

To transfer torque from the impeller to the turbine wheel. With the

Exhaust gas turbine while a gear is coupled, which is designed as a spur gear, comprising two gears. To the impeller, a gear is connected, which meshes with a gear of the turbine shaft of the exhaust gas turbine. With the turbine impeller, an output shaft is rotatably connected, which has a central resource supply channel, by means of

Working medium can be supplied to the working space. At the same time metered a partial flow for lubrication of a bearing assembly on which the impeller is supported, branched off. A general disadvantage of such spur gears are the relatively high radial forces occurring during operation, which make high demands on the storage of meshing gears. This is particularly disadvantageous when used in turbo-compound systems with rapidly rotating exhaust gas turbines. Furthermore, with relatively small spur gears only relatively low

Translations feasible, so that the meshing gears must be performed relatively large construction. Finally, in spur gears, the shafts which are in driving connection with one another via the spur gears must always be arranged parallel to one another. This in turn leads to a larger space of such a transmission.

The present invention has for its object to provide a turbo-compound system, which is improved over the embodiments according to the prior art. In particular, the space requirement of such a turbo-compound system should be reduced. At the same time an optimal and effective lubrication of the bearing assembly of the transmission of the turbo-compound system is to be ensured.

The object of the invention is achieved by a turbo-compound system with the features of claim 1. In the dependent claims are

indicated advantageous and particularly expedient embodiments of the invention.

An inventive turbo-compound system, in particular a

Motor vehicle, comprising an internal combustion engine having an output shaft and an exhaust gas turbine, which in the exhaust stream of

Internal combustion engine is arranged and has an impeller which is rotatably mounted on a turbine shaft. The exhaust gas turbine is about a transmission gear in a drive connection with the output shaft of

Internal combustion engine to transmit drive power through the transmission gear to the output shaft. Furthermore, a hydrodynamic coupling provided, which has an impeller and a turbine wheel, which together a toroidal, can be filled via an inlet with working fluid

Form working space to transfer torque hydrodynamically from the impeller to the turbine wheel. It is at least a gear of the

Transmission gear lubricated with working fluid of the hydrodynamic coupling. The transmission gear is further arranged in a drive connection between the hydrodynamic coupling and the exhaust gas turbine.

According to the transmission gear is designed as a planetary gear, comprising a sun gear, at least one planetary gear and a ring gear, which are engaged with each other. The one planetary or a variety of

Planetary wheels are mounted on a planet carrier. In the planet carrier, a lubricant channel for lubricating at least the sun gear, ring gear and / or at least one planetary gear or the plurality of planet wheels is arranged with working fluid.

Advantageously, the impeller or turbine is rotatably mounted on an input shaft. Here is the hydrodynamic coupling and the

Transmission gear assigned to a common working fluid supply, which is arranged in the input shaft and fluidly connected to the inlet of the hydrodynamic coupling or connectable. Over the common working medium supply can thus working medium the working space of the

fed hydrodynamic coupling and at the same time the bearings of the

Planetary gear and preferably the planetary gear bearings are optimally lubricated. As a result, the life of such a turbo-compound system is significantly increased.

The invention will now be explained by way of example with reference to exemplary embodiments and the figures.

Show it: Figure 1 shows a basic structure of the drive connection between the

Exhaust gas turbine and the crankshaft of the internal combustion engine; Figure 2 shows an embodiment according to the figure 1 with additional

Turbocharger;

Figure 3 shows a preferred embodiment of a hydrodynamic coupling of the turbo-compound system.

FIG. 1 shows a drive train between an exhaust gas turbine 3 and an output shaft 2, for example a crankshaft, of an internal combustion engine 1. In power transmission direction of the exhaust gas turbine 3 to the engine 1, a transmission gear 8 and a

hydrodynamic coupling 4 arranged one behind the other. The hydrodynamic coupling 4 comprises an impeller 5 and a turbine wheel 6, which has a

Working space 7, in which a hydrodynamic circulation flow can form, limit. Here, in the present case, the impeller 5 rotatably with an input shaft 11 and the turbine 6 also rotatably with a

Output shaft 10 of the hydrodynamic coupling 4 connected. The latter is here via a gear pair in drive connection with the output shaft 2 of the

Internal combustion engine 1. It is advantageous if the hydrodynamic coupling 4 is designed as a controllable clutch. According to the transmission gear 8 is designed as a planetary gear, comprising a sun gear 12, two planetary gears 13 and a ring gear 14.

Of course, it is conceivable that instead of the two illustrated planetary gears 13, fewer or more planetary gears are provided. To support the planet gears 13, a planetary carrier 15 is provided, which is rotatably connected to the input shaft 11 and the secondary side of Transmission 8 forms. The planet carrier 15 could also be formed by the input shaft 11.

On the primary side of the transmission gear 8, the sun gear 12 is rotatably connected to a turbine shaft 9, on which a not shown turbine runner is rotatably mounted.

In the present case, the ring gear 14 is fixed, which is not mandatory. The operation of the powertrain shown is as follows: The exhaust gas exiting the internal combustion engine 1 acts on the turbine runner of the exhaust gas turbine 3, whereby drive power is transmitted to the sun gear 12 via the turbine shaft 9. The meshing with the sun gear 12 and the ring gear 14 planet gears 13 transmit the power through the

Planet carrier 15 and the input shaft 11 to the impeller 5. When filling the working space 7, preferably at a full filling, is

Torque or rotational power of the input shaft 11 via the

Turbine 6, the output shaft 10 and the gear pair transmitted to the output shaft 2 of the engine 11.

FIG. 2 shows the article from FIG. 1 according to a further development. In this case, substantially the same components are provided with the same reference numerals. In addition to the exhaust gas turbine 3, an exhaust gas turbine 17 is a

Exhaust gas turbocharger 16 is provided, which viewed in the flow direction of the exhaust gas of the exhaust gas turbine 3 is connected upstream. Thus, the exhaust gas leaving the internal combustion engine 1 first acts on the exhaust gas turbine 17. The exhaust gas exiting from the exhaust gas turbine 17 or flowing past it is fed to the exhaust gas utilization turbine 3. With the exhaust gas turbine 17 is a

Fresh air compressor 18 of the exhaust gas turbocharger 16 in drive connection to one out To compress the ambient sucked airflow and supply the internal combustion engine 1 to its charge.

As can be seen in Figures 1 and 2, the output shaft 10, the

Input shaft 11 and the turbine shaft 9 arranged concentrically with each other. However, this does not necessarily have to be the case.

In the figure 3 is a preferred embodiment of the hydrodynamic

Clutch 4 of the turbo-compound system according to the invention in one

Axial section through the axis of rotation of the hydrodynamic coupling 4 shown. Again, the same components are provided with the same reference numerals as before.

As can be seen in FIG. 3, an axial bore is introduced both in the output shaft 10 and in the input shaft 11. The latter or both serve as common, the hydrodynamic coupling 4 and the

Of course, the axial bore could be incorporated exclusively in the output shaft 10 or the input shaft 11, or only one of the two holes for working fluid supply can be used. In the present case, the

Output shaft 10 and the input shaft 11 arranged concentrically with each other, wherein the facing surfaces form a gap. So can one

Partial flow from the working medium supply 19 in the region of the separation gap between the impeller 5 and turbine 6 (symmetry plane) and an inlet 20 into the working space 7 to fill it.

On the input side of the hydrodynamic coupling 4, the planet carrier 15 is designed to rotate with the input shaft 11. The latter could also be formed integrally with the input shaft 11. The planet carrier 15 has in its interior a lubricant channel 21, which is flow-conductively connected to the working medium supply 19. The planet carrier 15 in each case has a boom, comprising a first section extending in the radial direction and a second section extending in the axial direction. On the latter, a planetary gear 13 is mounted in each case. The number of cantilevers is dependent on the number of planetary gears 13. The lubricant channel 21 opens here in each case in the axially extending portion of the boom, there in the region of the bearing assembly of the planetary gear 13 to lubricate this.

The lubricant channel 21 can also be used for lubrication of a bearing assembly, not shown, of the ring gear 14 and / or the sun gear 12. For this purpose, the lubricant channel can open in the region of the bearing arrangement of the corresponding gear.

The lubricant channel 21 can via a plurality of radial and / or

Axial holes in the planet carrier 15 can be realized.

Due to the use of a planetary gear relatively low radial forces are achieved in the operation of the exhaust gas turbine compared to the spur gear, whereby the bearing assembly of the transmission is less heavily loaded. At the same time can be achieved by the planetary gear relatively large translations, at the same time compact design of the transmission and thus the entire turbo compound system. Finally, by the construction according to the invention, the input, output and the turbine shaft are performed concentrically with each other, which allows additional compactness of the turbo-compound system. LIST OF REFERENCE NUMBERS

1 internal combustion engine

2 output shaft

3 exhaust gas turbine

4 hydrodynamic coupling

5 impeller

6 turbine wheel

7 workspace

8 Transmission gears

9 turbine shaft

10 output shaft

11 input shaft

12 sun wheel

13 planetary gear

14 ring gear

15 planet carrier

16 turbocharger

17 exhaust gas turbine

18 fresh air compressors

19 working fluid supply

20 inlet

21 lubricant channel

Claims

claims

1. Turbo-compound system, in particular of a motor vehicle,

1.1 with an internal combustion engine (1) having an output shaft (2);

1.2 with an exhaust gas turbine (3), in the exhaust stream of

Internal combustion engine (1) is arranged and having an impeller which is rotatably mounted on a turbine shaft (9);

1.3 the exhaust gas turbine (3) is connected via a transmission gear (8) in a drive connection with the output shaft (2) of the internal combustion engine (1) to transmit drive power via the transmission gear (8) to the output shaft (2);

1.4 with a hydrodynamic coupling (4) which has an impeller (5) and a turbine wheel (6), which together form a toroidal, via an inlet (20) filled with working fluid working space (7) to hydrodynamically torque from the impeller (5 ) to the turbine wheel (6) to transfer; in which

1.5 at least one gear of the transmission gear (8) with working fluid of the hydrodynamic coupling (4) is lubricated, and

1.6 the transmission gear (8) in the drive connection between the

hydrodynamic coupling (4) and the exhaust gas turbine (3) is arranged; characterized in that

1.7 the transmission gear (8) is designed as a planetary gear,

comprising a sun gear (12), at least one on a planet carrier (15) mounted planet gear (13) and a ring gear (14) which are engaged with each other; and

1.8 in the planet carrier (15) a lubricant channel (21) for lubrication

at least of the sun gear (12), ring gear (14) and / or at least one planetary gear (13) is arranged with working fluid.

2. Turbo-compound system according to claim 1, characterized in that that the impeller (5) or turbine wheel (6) rotatably on a

Is mounted input shaft (11);

2.1 with one of the hydrodynamic coupling (4) and the

Transmission gear (8) associated common

Working medium supply (19) which is arranged in the input shaft (11) and flow-conductively connected to the inlet (20) or connectable; in which

2.2 the lubricant channel (21) flow-conducting with the common

Working medium supply (19) is connected.

3. Turbo-compound system according to claim 1 or 2, characterized

characterized in that the lubricant channel (21) extends substantially in the radial direction of the hydrodynamic coupling (4).

4. turbo-compound system according to one of claims 1 to 3, characterized in that the turbine shaft (9) of the exhaust gas turbine (3) rotatably connected to the sun gear (12) or is in drive connection therewith or in such can be brought ,

5. turbo-compound system according to one of claims 1 to 4, characterized in that the impeller (5) of the hydrodynamic coupling (4) with the planet carrier (15) is connected or is in drive connection therewith or in such can be brought ,

6. turbo-compound system according to one of claims 1 to 5, characterized in that the lubricant channel (21) in the region of

Bearing arrangement, via which the ring gear (14), sun gear (12) and / or at least one planet gear (13) is supported in the planetary gear, opens. Turbo-compound system according to one of claims 1 to 6, characterized in that the output shaft (2), the clutch shaft (11) and the turbine shaft (9) are arranged concentrically with each other.

8. turbo-compound system according to one of claims 1 to 7, characterized in that the working medium supply (19) in the form of a in the axial direction through the input shaft (11) extending channel, in particular over the entire axial length, advantageously in both end faces of Input shaft (11) opening, running channel is executed.