CH715786B1 - Turbocharger. - Google Patents

Abstract

Turbocharger, with a turbine (2) for expanding a first medium, the turbine (2) having a turbine housing and a turbine rotor (5), with a compressor for compressing a second medium using in the turbine (2) when expanding the energy obtained from the first medium, the compressor having a compressor housing and a compressor rotor which is coupled to the turbine rotor (5) via a shaft (8), with a bearing housing (9) which is arranged between the turbine housing and the compressor housing and in which the shaft (8) via a bearing (18) facing the turbine (2) is mounted, with a closing disk (22) which is located on a side of a bearing ring or a bearing bushing (19) of the bearing (18 ) connects to the bearing ring or bearing bush (19). A turbulence chamber (24) open in the direction of the bearing ring or the bearing bush (19) is built into the closing disc (22) on an axial surface (23) facing the bearing ring or the bearing bush (19) of the bearing (18) facing the turbine (2). introduced, which collects and derives the oil which escapes from a lubricating gap (20) of the bearing (18).

Description

The invention relates to a turbocharger.

The basic structure of a turbocharger is known to the person skilled in the art addressed here. A turbocharger has a turbine in which a first medium is expanded. A turbocharger also has a compressor in which a second medium is compressed using the energy obtained in the turbine when the first medium expands. The turbocharger turbine has a turbine housing and a turbine rotor. The compressor of the turbocharger has a compressor housing and a compressor rotor. A bearing housing is positioned between the turbine housing of the turbine and the compressor housing of the compressor, the bearing housing being connected to the turbine housing on the one hand and to the compressor housing on the other hand. A shaft is mounted in the bearing housing, via which the turbine rotor is coupled to the compressor rotor.

A turbocharger with a compressor, a turbine and a bearing housing is known from DE 10 2010 038 527 A1. A shaft, via which the turbine rotor is coupled to the compressor rotor, is mounted in the bearing housing, specifically via a plurality of plain bearings. A sliding bearing, which serves to support the shaft in the bearing housing, faces the turbine. Another sliding bearing, which serves to mount the shaft in the bearing housing, faces the compressor. The bearing facing the turbine is adjoined by a closing disk which, if the plain bearing has a floating bearing ring or a floating bearing bush, limits the axial displacement of the bearing ring or the bearing bush in the direction of the turbine, and which then, if the Bearing bush or the bearing ring is fixed, the holding of the bearing bush or the bearing ring is used.

An essential requirement with regard to the operational reliability of a turbocharger consists in the oil-tightness of the bearing of the shaft, in particular towards the turbine wheel of the turbine. On the hot turbine side in particular, there is a risk that oil escaping from the bearing housing could ignite. For this reason, shaft seals for supporting the shaft in the bearing housing are essential components for the operational safety of turbochargers.

There is therefore a need for a turbocharger in which simple means can be used safely and reliably to provide oil-tightness for mounting the shaft in the bearing housing, in particular adjacent to the turbine. Proceeding from this, the object of the present invention is to create a new type of turbocharger.

[0006] This object is achieved by a turbocharger according to claim 1. According to the invention, on an axial surface facing the bearing ring or the bearing bush of the bearing facing the turbine, a turbulence space is introduced into the closing disk which is open in the direction of the bearing ring or the bearing bush and collects and drains oil escaping from a lubricating gap of the bearing. According to the invention, it is proposed that the closing disk, which adjoins the bearing ring or the bearing bush of the bearing of the shaft facing the turbine, adjacent to the turbine, has a turbulence chamber which is open in the direction of the bearing ring or the bearing bush. Oil escaping from the lubricating gap of the bearing can enter the turbulence chamber open in the direction of the bearing ring or the bearing bush and be collected and settled there. The turbulence chamber drains away collected and calmed oil in the direction of an oil drain in the area of the bearing housing. In this way, oil-tightness for the bearing of the shaft in the bearing housing can be ensured, in particular adjacent to the turbine. The operational reliability of the turbocharger can thus be increased with simple means.

According to a further development of the invention, the turbulence chamber of the lens which is open in the direction of the bearing ring or the bearing bush is limited on a side facing away from the bearing ring or the bearing bush by a closed axial wall and on a radially outer side by a closed radial wall. The turbulence chamber of the cover disk, which is open in the direction of the bearing ring or the bearing bush, is delimited on a radially inner side facing the shaft by a web which, starting from the axial wall, forms the open turbulence chamber on the side facing away from the bearing ring or the bearing bush is limited, extends in the axial direction to the axial surface facing the bearing ring or the bearing bush and ends at a distance from this axial surface. Such a contouring of the turbulence chamber of the cover disc, which is open in the direction of the bearing ring or the bearing bush, is particularly preferred in order to reliably collect and calm oil escaping from the lubricating gap of the bearing.

Preferably, the open turbulence chamber is contoured such that an extension of a chamfer of the bearing ring or bearing bush facing the turbulence chamber intersects the closed axial wall. These details also serve to safely catch and calm the oil that escapes from the lubricating gap of the bearing.

The web, which delimits the turbulence chamber radially on the inside, defines a sealing gap to the shaft, the axial length of which is preferably between 0.1 times and 0.7 times the axial thickness of the lens and/or the radial width of which is preferably between between 2 and 20 times the radial bearing clearance between the bearing ring or bearing bush and the shaft. These details of the closing disc, namely the web delimiting the turbulence chamber radially inwards in sections, are advantageous in order to reliably collect the oil which leaves the lubricating gap.

Preferred developments of the invention result from the dependent claims and the following description. Exemplary embodiments of the invention are explained in more detail with reference to the drawing, without being limited thereto. 1 shows a cross section through a turbocharger, FIG. 2 shows a detail of a turbocharger according to the invention, FIG. 3 shows a detail of FIG. 2, and FIG. 4 shows a further detail of a turbocharger according to the invention.

shows the basic structure of a turbocharger 1. A turbocharger 1 has a turbine 2 for expanding a first medium, in particular for expanding exhaust gas from an internal combustion engine. Furthermore, a turbocharger 1 has a compressor 3 for compressing a second medium, in particular charge air, using energy obtained in the turbine 2 during the expansion of the first medium.

The turbine 2 has a turbine housing 4 and a turbine rotor 5. The compressor 3 has a compressor housing 6 and a compressor rotor 7. The compressor rotor 7 is coupled to the turbine rotor 5 via a shaft 8, which is mounted in a bearing housing 9 with the bearing housing 9 positioned between the turbine housing 4 and the compressor housing 5 and connected to both the turbine housing 4 and the compressor housing 5 .

The turbine housing 4 of the turbine 2 comprises an inflow housing 11 and an outflow housing 12. The inflow housing 11 can be used to supply the first medium to the turbine rotor 5 to be relaxed in the region of the turbine 2. The expanded first medium flows away from the turbine 2 via the outflow housing 12 in the area of the turbine rotor 5 .

In addition to the inflow housing 11 and the outflow housing 12, the turbine housing 4 comprises an insert piece 13, with the insert piece 13 running in particular in the area of the inflow housing 11, specifically adjacent to the turbine rotor 5 radially on the outside adjacent to rotor blades 14 of the turbine rotor 5.

The turbine housing 4 further includes a nozzle ring 15. The nozzle ring 15 is also referred to as the turbine nozzle.

1 also shows a sealing cover 16 in the connection area of the inflow housing 11 and the bearing housing 9. The sealing cover 16 is also referred to as the bearing housing cover or heat shield.

The inflow housing 11 of the turbine 2 is connected to the bearing housing 9 via a fastening device 17, which is preferably designed as a clamping claw. A radially outer section of the sealing cover 15 is clamped in this connection area between the bearing housing 9 and the inflow housing 11 of the turbine. A section of the nozzle ring is preferably also clamped in this connection area.

As already stated, the turbine rotor 5 and the compressor rotor 7 are coupled via the shaft 8, which is mounted in the bearing housing 9. Bearings are used to support the shaft 8 in the bearing housing 9, namely a bearing facing the turbine 2 and a bearing facing the compressor 3, in order to support the shaft 8 along its axial extension via these bearings at at least two axial positions. 2 shows a section of a turbocharger in the area of a bearing 18 which serves to support the shaft 8 in the bearing housing 9 on a side of the shaft 8 or bearing housing 9 facing the turbine 2 or the turbine wheel 5 of the turbine 2 .

This bearing 18 facing the turbine or the turbine wheel 5 is a radial plain bearing which comprises a bearing ring or a bearing bush 19 . Between the bearing ring or the bearing bush 19 and the shaft 8 there is a lubricating gap 20 which can be supplied with oil via a bore 21 in the bearing housing 9 .

At the bearing ring or the bearing bush 19 of the bearing 18 closes on the turbine 2 or the turbine wheel 5 side facing a cover plate 22 at. Then, when the bearing ring 19 or the bearing bush of the bearing 18 is accommodated in a floating manner in the bearing housing 9, the closing disc 22 limits the axial mobility of the bearing ring or the bearing bush 19. In the case of a fixed bearing ring or a fixed bearing bush 19, the closing disc 22 holds the bearing ring or the bearing bush 19 fixed in the axial direction.

During operation, oil can escape from the lubricating gap 20 between the bearing ring 19 or the bearing bush and the shaft 8, also in the direction of the turbine wheel 5 To ensure turbine 2, a turbulence chamber 24 open in the direction of the bearing ring or the bearing bush 19 is formed according to the invention in the closing disk 22, which is designed in one piece or in one piece, on an axial surface 23 facing the bearing ring or the bearing bush 19. Oil escaping from the lubricating gap 20 in the region of a chamfer 25 of the bearing ring or bearing bush 19 facing the turbulence space 24 can be collected in this turbulence space 24 and settled in the turbulence space 24 .

The turbulence chamber 24 runs around in the circumferential direction and has an oil drain opening 26 at one circumferential position, via which the oil collected and calmed in the turbulence chamber 24 can be discharged in the direction of an oil drain of the bearing housing 9 . This oil drain opening 26 has an opening angle β between 5° and 90° in the circumferential direction.

As already stated, the turbulence chamber 24 is open in the direction of the bearing ring 1 or the bearing bush 19 of the bearing 18 . This turbulence space 24 , which is open in the direction of the bearing ring or the bearing bush 19 , is delimited on a side facing away from the bearing ring or the bearing bush 19 by a closed axial wall 27 and radially on the outside by a closed radial wall 28 . Starting from the axial wall 27, which delimits the turbulence space 24 on the side facing away from the bearing ring or the bearing bush 19 of the bearing 18, a web 29 extends in the direction of the bearing ring or the bearing bush 19, which radially inwardly adjoins the turbulence space 24 to the shaft 8 is limited in sections and which ends at a distance in front of the axial surface 23 of the end disk 22 facing the bearing ring or the bearing bush 19 . Accordingly, the web 29 has an axial length that is less than the axial thickness or width of the cover plate 22.

The web 29, which defines a sealing gap 30 towards the shaft 8, has an axial length which is between 0.1 times and 0.7 times the axial thickness or axial width of the end disk 22.

The radial width of the sealing gap 30 between the web 29 of the cover disk 22 and the shaft 8 is between 2 and 20 times the radial bearing play between the bearing ring 19 of the bearing 18 and the shaft 8.

In order to optimally collect the oil escaping from the lubricating gap 20 of the bearing 18 in the region of the turbulence chamber 24, which is designed to be open in the direction of the bearing ring or the bearing bush 19, the turbulence chamber 24 is contoured in particular in such a way that an extension of that chamfer 25 of the bearing ring or bearing bush 19, which diverges in the direction of the turbulence chamber 24, intersects the closed axial wall 27 which delimits the turbulence chamber 24 on the side remote from the bearing ring or bearing bush 19.

In Fig. 3, this extension of the chamfer 25 is shown in dashed lines. The extension of the chamfer 25 intersects the closed axial wall 27, in particular in the transition area to the closed radial wall 28, which delimits the turbulence chamber 24 radially on the outside.

With the invention it is therefore proposed that in the cover plate 22, which is arranged between the turbine wheel 5 and the bearing 18, which supports the shaft 8 on the side facing the turbine 2 in the bearing housing 9, in the direction of the bearing ring or the bearing bush 19 of the bearing 18 open turbulence space 24 is introduced. Oil that escapes from the lubricating gap 20 between the bearing ring or the bearing bush 19 of the bearing 18 and the shaft 8 reaches the area of the turbulence chamber 24, where it is collected and calmed down and via the turbulence chamber 24 running in the circumferential direction in the direction of the oil drain opening 26 the lens 22 out. In this way, the collected oil can be drained off in a defined manner.

The turbulence chamber 24 is delimited radially on the inside by the web 29, radially on the outside by the radial wall 28 and on the side facing away from the bearing ring or the bearing bush 19 by the axial wall 27. An extension of the chamfer 25 of the bearing ring or the bearing bush preferably intersects 19 this axial wall 27. Adjacent to the bearing ring or the bearing bush 19, the turbulence chamber 24 is open.

In the region of that bearing which supports the shaft 8 on the side facing the compressor 3, a cover plate, as described above, can also be arranged.

Reference List

1 Turbocharger 2 Turbine 3 Compressor 4 Turbine housing 5 Turbine rotor 6 Compressor housing 7 Compressor rotor 8 Shaft 9 Bearing housing 10 Silencer 11 Inflow housing 12 Outflow housing 13 Insert 14 Rotor blade 15 Nozzle ring 16 Sealing cover 17 Fastening device 18 Bearing 19 Bearing ring/bearing bush 20 Lubricating gap 21 Bore 22 Closing disk 23 Axial surface 24 turbulence space 25 chamfer 26 oil drainage opening 27 axial wall 28 radial wall 29 web 30 radial gap

Claims (10)

1. Turbocharger (1), with a turbine (2) for expanding a first medium, the turbine (2) having a turbine housing (4) and a turbine rotor (5), with a compressor (3) for compressing a second medium using energy obtained in the turbine (2) when the first medium expands, the compressor (3) having a compressor housing (6) and a shaft connected to the turbine rotor (5). (8) has a coupled compressor rotor (7), with a bearing housing (9) arranged between the turbine housing (4) and the compressor housing (6), in which the shaft (8) is mounted via a bearing (18) facing the turbine (2), with an end disk (22) which adjoins the bearing ring or the bearing bush (19) on a side of a bearing ring or a bearing bush (19) of the bearing (18) facing the turbine (2) that faces the turbine (2), characterized in that ,that introduces a turbulence space (24) open in the direction of the bearing ring or the bearing bush (19) into the closing disk (22) on an axial surface (23) facing the bearing ring or the bearing bush (19) of the bearing (18) facing the turbine (2). is the oil, which escapes from a lubricating gap (20) of the bearing (18), catches and drains. 2. Turbocharger according to Claim 1, characterized in that the cap (22) is made in one piece. 3. Turbocharger according to claim 1 or 2, characterized in that the turbulence chamber (24) runs in the circumferential direction and has an oil drain opening (26) at a circumferential position. Turbocharger according to Claim 3, characterized in that the oil drain opening (26) has a circumferential opening angle of between 5° and 90°. 5. Turbocharger according to one of claims 1 to 4, characterized in that the in the direction of the bearing ring or the bearing bush (19) open turbulence space (24) of the cover disc (22) on a side facing away from the bearing ring or the bearing bush (19) by a closed axial wall (27) and is delimited on a radially outer side by a closed radial wall (28). A turbocharger according to claim 5, characterized in that the open turbulation space (24) is contoured such that an extension of a chamfer (25) of the bearing ring or bushing (19) facing the turbulation space (24) intersects the closed axial wall (27). 7. Turbocharger according to claim 6, characterized in that the extension of the turbulence chamber (24) facing chamfer (25) of the bearing ring (19) or the bearing bush (19) intersects the closed axial wall (27) in the transition area to the closed radial wall (28). 8. Turbocharger according to one of claims 1 to 7, characterized in that in the direction of the bearing ring or the bearing bush (19) open turbulence space (24) of the cover plate (22) on a radially inner side facing the shaft (8) by a Web (29) is limited. 9. Turbocharger according to claim 8, characterized in that the web (29), starting from the axial wall (27) which limits the open turbulence chamber (27) on the side facing away from the bearing ring or the bearing bush (19), in the direction of the dem Bearing ring or the bearing bush (19) facing axial surface (23) extends and at a distance from this axial surface (23) ends. 10. Turbocharger according to claim 8 or 9, characterized in that the web (29) defines a sealing gap (30) to the shaft (8), the axial length of which is between 0.1 and 0.7 times the axial thickness of the Closing disc (22) and/or its radial width is between 2 and 20 times the radial bearing play between the bearing ring (19) or the bearing bush and the shaft (8).