WO2015044242A1

WO2015044242A1 - Bearing housing ventilation system for a turbocharger arrangement

Info

Publication number: WO2015044242A1
Application number: PCT/EP2014/070433
Authority: WO
Inventors: William Gizzi
Original assignee: Abb Turbo Systems Ag
Priority date: 2013-09-27
Filing date: 2014-09-25
Publication date: 2015-04-02
Also published as: DE102013110726A1

Abstract

The invention relates to a bearing housing ventilation system for a turbocharger arrangement. The bearing housing ventilation system for a turbocharger arrangement (10) comprises a compressor-side housing (12) through which a compressor-side working medium flows, a turbine-side housing (13) through which a turbine-side working medium flows, and a bearing housing (11). The bearing housing (11) is arranged between the compressor-side housing (12) and the turbine-side housing (13), and a leakage flow from one or both of the two housings (12, 13) enters the bearing housing. The bearing housing ventilation system comprises at least one jet pump (2) with which a suction medium can be suctioned and conducted by means of a propellant jet, the working medium of one or both housings being used as the propellant in order to suction the leakage flow as the suction medium from the bearing housing (11).

Description

Bearing housing ventilation system for a turbocharger assembly

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a bearing housing ventilation system for a

A turbocharger assembly for bleeding the bearing housing of a turbocharger and a multi-stage turbocharger assembly with a Lagergehäuseentlüftungssystem.

STATE OF THE ART

It is known from the prior art that during operation of a turbocharger, so-called blow-by losses may occur. Under blow-by losses is usually a leakage mixture, which can also be referred to as leakage flow to understand oil and gas. This leakage mixture collects in the oil-bearing

Lagergehäusaum a turbocharger after it penetrates via a compressor-side housing and / or a turbine-side housing via leaking areas in the bearing housing space. The leakage mixture passes through an oil drain line into the oil system and into the crankcase space of the engine connected to the turbocharger. These resulting gas losses must be vented to a pressure build-up in

Crankcase of the engine to compensate. A known from the prior art solution of venting the crankcase is described in US 2009/0308364. Therein a jet pump is used. A first port of the jet pump is connected to an output of a compressor-side housing of a turbocharger, a second

Connection of the jet pump is connected to the crankcase of the engine and a third port of the jet pump is connected to the input of the compressor side housing to supply the suctioned from the crankcase of the engine leakage mixture back to the compressor side housing. A pressure differential between the first and third ports of the jet pump creates a vacuum in the second port to exhaust the leakage mixture from the crankcase of the engine. However, before the aspirated leakage mixture can be re-supplied to the turbocharger, the oil contained in the leakage mixture must be eliminated. Because the oily leakage mixture would otherwise contaminate the compressor side of the turbocharger, which would thereby lose efficiency. The oil separation is usually via an oil separator, which must be installed in addition, otherwise the

Compressor side of the turbocharger should be cleaned regularly during maintenance.

In addition, there is a risk that the oily leakage mixture on the hot diffuser walls of the turbocharger precipitates and begins to coke from a certain temperature. This in turn leads to a loss of efficiency and a significant maintenance overhead of the turbocharger.

SUMMARY OF THE INVENTION It is an object of the present invention to further develop a bearing housing bleeding system for a turbocharger assembly so that a leakage flow existing in the bearing housing of a turbocharger assembly is easily and inexpensively removed and a loss of oil in the bearing housing is minimized. In addition, the maintenance of the turbocharger to be reduced, which is caused by the leakage flow.

The object is solved by the features of independent claim 1.

In particular, the object is achieved by a bearing housing ventilation system for a

Turbochargeranordnung solved, wherein the turbocharger assembly comprises a compressor-side housing, which is flowed through by a compressor-side working fluid, a turbine-side housing, which is flowed through by a turbine-side working fluid and a bearing housing, wherein the bearing housing between the compressor-side housing and the turbine-side housing is arranged, and wherein from one of the two or both housing a leakage flow in the respectively adjacent arranged

Bearing housing penetrates. The bearing housing ventilation system comprises at least one jet pump with which a suction medium can be sucked in and conveyed by means of a motive medium jet, wherein the working medium of one of the two is used as a propellant

Housing is used to suck the leakage flow as a suction medium from the housing adjacent to the arranged bearing housing. Through the use of a jet pump, which is used to vent the bearing housing of the turbocharger assembly, the advantage is achieved that can be dispensed with the use of a motor-driven pump, for their operation otherwise an additional power supply would be required. The suction of the leakage flow is thereby with a reduced energy consumption, since no additional energy source for operating the jet pump is needed.

Due to the arranged adjacent to the bearing housing housing with the as

Treibmedium used working medium give short ways for the

inventive ventilation system

Another advantage of the present invention is that pressure build-up in the crankcase space is prevented or at least substantially reduced. Because the leakage flow is already sucked in the bearing housing, it is avoided that large amounts of the leakage flow from the bearing housing into the engine compartment occur.

Another advantage of the present invention is also that a

Engine system, which may include a crankcase ventilation, can be made smaller, since a smaller pump and a smaller oil separator is necessary. In addition, the existing measures to reduce the leakage flow, such as built-piston ring systems, supported, since by the suction of the

Leakage flow reduces the amount of leakage flow that can pass from the turbocharger into the crankcase space.

PREFERRED EMBODIMENTS OF THE INVENTION

In a preferred embodiment of the present invention, the jet pump is connected to an outlet of the compressor-side housing, so that the driving medium flows from the compressor-side housing to the jet pump.

In a preferred embodiment of the present invention, the jet pump is connected to an inlet of the turbine-side housing for the driving medium to flow from the turbine-side housing to the jet pump.

In a preferred embodiment of the present invention, the leakage flow extracted from the bearing housing of the turbocharger assembly is supplied to an inlet of the compressor-side housing. Prior to feeding, it may be advantageous that the oily components of the leakage flow are separated by an oil filter, so that the compressor stage of the turbocharger is not contaminated by oil-containing components, which would otherwise reduce the efficiency of the turbocharger.

In a preferred embodiment of the present invention, the leakage flow extracted from the bearing housing of the turbocharger assembly is supplied to an outlet of the turbine-side housing.

In a preferred embodiment of the present invention, the jet pump is designed as a venturi nozzle or as a Laval nozzle. The use of such a nozzle has the advantage that for the operation of the jet pump no additional electrical energy source

must be provided.

In a preferred embodiment of the present invention, a filter element is provided which is connected to the jet pump and the bearing housing. This is the advantage that an oil separation of the leakage flow is made before the extracted from the bearing housing leakage flow enters the jet pump. The compressor stage is then not included in the leakage flow

Contaminated oil components when the leakage flow is discharged back after exiting the jet pump via an inlet in the compressor-side housing of the turbocharger. In this way, the maintenance can be reduced. At the same time, the oil loss of the oil system is reduced to a minimum. In a preferred embodiment of the present invention, a check valve is provided which is connected to the jet pump and the bearing housing. The check valve is preferably integrated in a line which carries the suctioned leakage flow. This has the advantage that a backflow of sucked leakage flow is prevented. In addition, it prevents in this way that no hot and high pressure air from the compressor side of the turbocharger passes into the bearing housing. In a preferred embodiment of the present invention is a

Turbocharger arrangement provided with a Lagergehäuseentlüftungssystem.

In a preferred embodiment of the present invention, a multi-stage turbocharger arrangement is provided with a number of turbochargers, each turbocharger each comprising a compressor-side housing, which is flowed through by a compressor-side working fluid, a turbine-side housing, which is flowed through by a turbine-side working fluid and a bearing housing , wherein from one of the two or both housing a leakage flow penetrates into the bearing housing. The multi-stage turbocharger assembly includes a first-stage turbocharger having a bearing housing ventilation system and at least one second one

Stage formed turbocharger, wherein the bearing housing of at least the second stage of the turbocharger assembly is connected to the bearing housing ventilation system of the first stage of the turbocharger assembly. The advantage for such a multi-level

Turbocharger arrangement is that only a single bearing venting system with a correspondingly sized jet pump must be used to vent the individual bearing housings of the number of interconnected stages of turbochargers.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described below with reference to exemplary embodiments, which are explained in more detail with reference to drawings. Hereby show:

Fig. 1 shows a bearing housing ventilation system for a turbocharger assembly according to a first embodiment of the present invention;

Fig. 2 shows a bearing housing ventilation system for a turbocharger assembly according to a second embodiment of the present invention;

3 shows a bearing housing ventilation system for a multistage turbocharger arrangement according to a third embodiment of the present invention;

4 shows a bearing housing ventilation system for a multistage turbocharger arrangement according to a fourth embodiment of the present invention. In the following description, identical reference numerals are used for the same and like-acting parts.

DETAILED DESCRIPTION OF THE DRAWINGS

Fig. 1 shows a first embodiment of a bearing housing ventilation system 1 for a turbocharger assembly 10. The bearing housing ventilation system 1 is connected to the

Turboladerordnung 10 connected, which as a single-stage turbocharger assembly 10th

is trained. The turbocharger assembly 10 is connected to a motor 40. The

Turbocharger assembly 10 includes a bearing housing 1 1, which on the compressor side with the compressor-side housing 12, which is flowed through by a compressor-side working fluid, and on the turbine side with a turbine-side housing 13, which is flowed through by a turbine-side working fluid, wherein the bearing housing 1 1, as shown in Fig. 1, between the compressor-side housing 12 and the turbine-side housing 13 is arranged, and wherein from one of the two or both housings 12, 13, a leakage flow, a mixture of gas and lubricating oil, in the bearing housing penetrates. This may occur, for example, due to leaks between the bearing housing and the turbine-side and / or the compressor-side housing. The bearing housing 1 1 also includes an engine-side oil inlet 24 and an oil outlet 25th Dear the oil inlet 24 lubricating oil passes from the engine system 40 into the bearing housing 1 1 of the turbocharger assembly 10. Dear the oil outlet 25, the lubricating oil passes from the bearing housing 1 1 of the turbocharger 10 in the crankcase of the engine 40th Das

Turbine-side housing 13 includes an inlet 42, wherein the exhaust gases of the engine 40 are passed through the inlet 42 in the turbine-side housing 13. The turbine-side housing 13 also includes an outlet 27 through which exhaust gases are discharged into the environment.

The bearing housing venting system 1 in FIG. 1 includes a jet pump 2 connected to a compressor side housing 12 of the turbocharger assembly 10 for flowing a motive medium jet from the compressor side housing 12 into the jet pump. Alternatively, the jet pump 2 could be connected to the turbine-side housing 12 of the turbocharger arrangement 10, as shown in FIG. The jet pump 2 is designed in such a way that a suction medium called a leakage flow can be sucked out of the bearing housing 11 and conveyed by means of a driving medium jet, the working medium of the compressor-side housing 12 being used as the driving medium. The jet pump 2 is connected as follows to the turbocharger 10 of FIG. 1: The jet pump 2 is connected to the bearing housing 1 1 via a line 30. Furthermore, the jet pump 2 is connected to an outlet 26 of the compressor-side housing 12, so that the driving medium flows from the compressor-side housing 12 to the jet pump 2. The compressed air outlet 26 is also connected to the engine 40 via an inlet 43 for allowing compressed air to flow from the compressor side housing 12 to the engine 40. The compressor-side housing 12 further includes an inlet 23, through which the leaked from the bearing housing 1 1 leakage flow can be returned to the compressor side housing 12 when the leakage flow exiting the jet pump 2. Through the inlet 23, however, air is sucked from outside into the compressor-side housing 12. Alternatively, the sucked leakage flow can also be discharged via an outlet on the jet pump 2 into the environment (not shown).

Alternatively, a number of jet pumps could be used. In Fig. 1, a filter element 16 and a check valve 17 is disposed between the bearing housing 1 1 and the jet pump 2. The optional filter element 16, which may be formed, for example, as a cyclone, contributes to the separation of the oil-containing constituents from the leakage flow. The optional check valve 17, which is arranged in the line 30 between the bearing housing 1 1 and the jet pump 2, ensures that no hot and high pressure air flows from the compressor side into the bearing housing 1 1. The

Jet pump 2 is fluidically connected to the bearing housing 1 1 and the compressor-side housing 12. The jet pump 2 can be designed as a venturi nozzle or as a Laval nozzle.

FIG. 2 shows a second embodiment of a bearing housing ventilation system 1 for a turbocharger assembly 10 of the present invention. The embodiment according to FIG. 2 differs from the embodiment shown in FIG. 1 in that the jet pump 2 is connected to the bearing housing 11 of the turbocharger arrangement 10 via the line 30. Furthermore, the jet pump 2 is connected to the inlet 42 of the turbine-side housing 13 via the line 29. As a result, the driving medium can flow from the turbine-side housing 13 to the jet pump 2. The driving medium jet is thus fed in Fig. 2 by the working medium of the turbine-side housing 13. Alternatively or additionally, between the jet pump 2 and the bearing housing 1 1, a filter element 16 and a

Check valve 17 may be arranged, as shown in FIG. 2. The extracted from the bearing housing 1 1 leakage flow is through the filter element 16 of his

Oil components isolated. A possible return of the sucked from the bearing housing 1 1 of the turbocharger assembly 10 leakage flow is such that an outlet 28 of the jet pump 2 is connected to the outlet 27 for exhaust gases of the turbine-side housing 13. About the outlet 27 at the same time the exhaust gases from the turbine-side housing 13 are discharged into the environment. Alternatively, the suctioned leakage flow can also be discharged via an outlet 28 of the jet pump 2 into the environment.

3 shows a bearing housing ventilation system 1 for a multi-stage turbocharger assembly 50. The turbocharger assembly 50 includes a first stage turbocharger 51 and a second stage turbocharger 52. The first and second stages of the turbocharger assembly 50 are identically constructed in this embodiment and are no different from the turbocharger assemblies of the embodiments of FIGS. 1 and 2. The first stage turbocharger 51 is connected to a bearing housing ventilation system 1. The

Bearing housing ventilation system 1 consists of a jet pump 2 and an optional filter element 16. The jet pump 2 of the bearing housing ventilation system 1, as shown in Fig. 1, with the bearing housing 1 of the first stage turbocharger 51 and the compressor-side housing 12 of the turbocharger 51st connected to the first stage. The optional filter element 16 is disposed between the bearing housing 1 1 of the first stage turbocharger 51. Another optional filter element 16 may be disposed between the bearing housing 1 1 of the second stage turbocharger 52 and the jet pump 2. Alternatively, a check valve 17 (not shown) between the

Bearing housing 1 1 of the first stage turbocharger 51 and / or the bearing housing 1 1 of the second stage turbocharger 52 and the jet pump 2 may be arranged. The outlet 26 of the compressor-side housing 12 of the turbocharger 51 of the first Stage is connected to the inlet 23 of the compressor-side housing 12 of the second-stage turbocharger 52. The exhaust outlet 53 of the turbine-side housing 13 of the second-stage turbocharger 52 is connected to the inlet 54 of the turbine-side housing 13 of the turbocharger 51 of FIG. Stage connected. A conduit 30 connects the bearing housing 1 1 of the 2nd stage turbocharger 52 with the jet pump 2 of the bearing venting system 1 of the turbocharger 51 of FIG. Stage, so that a leakage flow is sucked out of the bearing housing 1 1 of the second stage turbocharger 51 and conveyed to the jet pump 2. The bearing housing 1 1 of the turbocharger 51 and the bearing housing 1 1 of the turbocharger 52 in each case comprises an oil outlet 25, which is connected to the motor 40. The bearing housing 1 1 of the turbocharger 51 and the bearing housing 1 1 of the turbocharger 52 each includes an oil inlet 24, which is connected to the motor 40, respectively. The turbocharger assembly 50 may consist of an arbitrary number of individual turbocharger stages with a corresponding interconnection. The advantage of the multistage turbocharger arrangement 50 shown in FIG. 3 is that only a single bearing venting system 1 with a correspondingly dimensioned

Jet pump 2 must be used to vent the individual bearing housing 1 1 any number of series-connected individual turbocharger stages.

4 shows another example of a bearing housing ventilation system 1 in a multi-stage turbocharger assembly 50 having a first stage turbocharger 51 and a second stage turbocharger 52. The turbocharger assembly 50 differs from the multi-stage turbocharger assembly 50 shown in FIG. 3 in that the jet pump 2 of the bearing housing ventilation system 1 is now connected to the turbine-side housing 13 of the first stage turbocharger 51. The jet pump 2 is, as already described in detail in the embodiment of FIG. 2, with the bearing housing 1 1 of the turbocharger 51 of the first Stage and via the line 30 with the inlet 42 of the turbine-side housing 13 of the turbocharger 51 of the first Stage connected. The outlet 26 of the compressor-side housing 12 of the turbocharger 51 of the first Stage is connected to the inlet 23 of the compressor-side housing 12 of the second-stage turbocharger 52. The outlet 26 of the compressor-side housing 12 of the second-stage turbocharger 52 is connected to the inlet 43 of the engine 40. The jet pump 2 comprises a first one

Connection, which the jet pump 2 with the bearing housing 1 1 of the turbocharger 51 of the 1st Stage connects. The bearing housing 1 1 of the turbocharger 52 of the second stage is connected via a line 30 to the first port of the jet pump 2. The jet pump 2 comprises a second port, which via a line 29 to the inlet 42 of

turbine-side housing 13 of the turbocharger 51 of the first Stage is connected. Alternatively, the sucked leakage flow can be discharged via the jet pump 2 into the environment (not shown). The jet pump 3 comprises a third connection, which alternatively with the exhaust gas outlet 27 of the turbine-side housing 13 of the turbocharger 51 of the first Stage may be connected when the sucked leakage flow is to be returned to the turbine-side housing 13. Alternatively, in line 30, an additional filter element 16 may be installed, which separates the oil from the

sucked leakage flow from the bearing housing 1 1 of the second stage turbocharger 52 before it flows into the jet pump 2.

LIST OF REFERENCE SIGNS

I bearing housing ventilation system

2 jet pump

10 turbocharger arrangement

I I bearing housing

12 compressor side housing

13 Turbine-side housing

16 filter element

17 check valve

23 entry in compressor-side housing

24 oil inlet from the motor side

25 Oil outlet from bearing housing of the turbocharger assembly 26 outlet from the compressor side housing

27 Outflow from turbine-side housing

28 exit

29 line

30 line

40 engine

42 entry in turbine-side housing

43 entry in engine

50 turbocharger arrangement

51 turbocharger of the 1. step

52 2nd stage turbochargers

53 Exhaust gas outlet of the turbocharger of the 2nd stage

54 Abgaseinritt the turbocharger of the 1st step

Claims

1 . Bearing housing ventilation system (1) for a turbocharger assembly (10), wherein the turbocharger assembly (10) a compressor-side housing (12), which is flowed through by a compressor-side working fluid, a turbine-side housing (13), which is flowed through by a turbine-side working fluid and a bearing housing ( 1 1), wherein the bearing housing (1 1) between the compressor-side housing (12) and the turbine-side housing (13) is arranged, and wherein one of the two or both housings (12, 13) a leakage flow into the bearing housing penetrates, comprising:

at least one jet pump (2) with which by means of a driving medium beam a

Suction medium can be sucked in and transported

wherein the working medium of one of the two housings (12, 13) is used as the driving medium to suck the leakage flow as the suction medium from the bearing housing (1 1).

2. Lagergehäuseentlüftungssystem (1) according to claim 1, characterized in that the jet pump (2) with an outlet (26) of the compressor-side housing (12) is connected, so that the driving medium from the compressor-side housing (12) to the jet pump (2) flows ,

3. Lagergehäuseentlüftungssystem (1) according to claim 1, characterized in that the jet pump (2) with an inlet (42) of the turbine-side housing (13) is connected, so that the driving medium from the turbine-side housing (13) to the jet pump (2) flows ,

4. Lagergehäuseentlüftungssystem (1) according to claim 1, characterized in that the from the bearing housing (1 1) of the turbocharger assembly (10) sucked leakage flow to an inlet (23) of the compressor side housing (12) is supplied.

5. Lagergehäuseentlüftungssystem (1) according to claim 1, characterized in that from the bearing housing (1 1) of the turbocharger assembly (10) sucked leakage flow to an outlet (27) of the turbine-side housing (13) is supplied.

6. Lagergehäuseentlüftungssystem (1) according to one of the preceding claims, characterized in that the jet pump (2) is designed as a Venturi nozzle.

7. Lagergehäuseentlüftungssystem (1) according to any one of the preceding claims, characterized in that a filter element (16) is provided, which with the jet pump (2) and the bearing housing (1 1) is connected to an oil separation from the leakage flow to effect, before sucked out of the bearing housing (1 1)

Leakage flow into the jet pump (2) occurs.

8. Lagergehäuseentlüftungssystem (1) according to any one of the preceding claims, characterized in that a check valve (17) is provided, which with the jet pump (2) and the bearing housing (1 1) is connected to a return flow of the sucked leakage flow prevent.

9. Turbocharger arrangement (10) with a bearing housing ventilation system (1) according to one of claims 1 to 8.

10. A multi-stage turbocharger assembly (50) comprising a number of turbochargers (51, 52), each individual turbocharger (51, 52) each having a compressor-side housing (12) through which a compressor-side working fluid flows, a turbine-side housing (13). , which is flowed through by a turbine-side working fluid and a bearing housing (1 1), wherein from one of the two or both housings (12, 13) enters a leakage flow into the bearing housing (1 1) ,, comprising:

a first stage formed as a turbocharger (51) with a

Bearing housing ventilation system (1) according to one of claims 1 to 8; and at least one second stage turbocharger (52), wherein the second stage bearing housing (11) of the turbocharger (52) is connected to the first stage bearing housing venting system (1) of the turbocharger (51).