WO2011087663A2

WO2011087663A2 - Bearing housing of an exhaust-gas turbocharger

Info

Publication number: WO2011087663A2
Application number: PCT/US2010/060212
Authority: WO
Inventors: Thomas Fitting
Original assignee: Borgwarner Inc.
Priority date: 2009-12-22
Filing date: 2010-12-14
Publication date: 2011-07-21
Also published as: WO2011087663A3

Abstract

The invention relates to a bearing housing (1) of an exhaust-gas turbocharger (24), having a mounting bore (2), having a bearing device (3) which has two bearing bushes (4, 5) which are arranged in the mounting bore (2) and between which a spacer (6) is arranged, having a rotational speed sensor (7) which engages into a sensor recess (8) of the spacer (6), and having a rig pin (9) which is screwed into a pin bore (10) and which engages with its pin head (19) into a pin recess (11) of the spacer (6), wherein the pin recess (11) is designed as a slot which is open to one end (12) of the spacer (6).

Description

BEARING HOUSING OF AN EXHAUST-GAS TURBOCHARGER

DESCRIPTION The invention relates to a bearing housing according to the preamble of claim 1 and to a spacer according to the preamble of claim 9 and of claim 14.

A generic bearing housing has a mounting bore in which a bearing device is arranged for mounting the shaft of the exhaust-gas turbocharger. Said bearing device has two bearing bushes, the spacing to one another is determined by a spacer arranged between the bearing bushes. In this way, a two-part floating bush bearing arrangement is preferably formed, wherein as a result of the rotation of the shaft, a torque is transmitted to the bearing bushes via the oil film, thereby causing a co-rotation of the bearing bushes at approximately half of the shaft rotational speed. Said torque is in turn transmitted by the bearing bushes at the end side to the spacer, such that, to prevent the co-rotation of the spacer, a so-called rig pin must be inserted into said spacer. Said rig pin is for example a screw which is screwed into the bearing housing from the outside and the screw end of which engages into a recess of the spacer. This prevents the co- rotation of the spacer, and this is necessary because a sensor for sensing the rotor shaft engages into a bore, which is arranged diametrically opposite the rig pin, of the spacer. Said sensor must be situated with its sensor head directly at the shaft surface without making contact with the shaft and without the sensor being damaged by a co-rotation of the spacer which would occur without the rig pin.

It is an object of the present invention to provide a bearing housing of the type specified in the preamble of claim 1 which can be assembled in a simple manner in relation to the prior art and which enables reliable prevention of the co-rotation of the spacer and therefore damage to the rotational speed sensor.

Said object is achieved by means of the features of claim 1.

Since the pin recess is designed as a slot which is open to one end of the spacer, it is possible to use both an internally situated rig pin and also an externally situated rig pin in the form of a cylinder-head screw screwed into the bearing housing, since in particular if an internally situated rig pin is provided, said rig pin is firstly screwed through the bore of the rotational speed sensor from the inside into the bearing housing, and subsequently the spacer can, by means of the pin recess which is open at one side or is in the form of a slot, be pushed over the cylinder-head screw or rig pin which is already located in the housing. Here, in the case of an internally situated rig pin, a collar which is preferably provided prevents the rig pin from being able to migrate toward the rotor shaft, and thereby damage the latter, in the event of a breakaway. The subclaims relate to advantageous refinements of the invention.

In particular, the pin recess may be designed as a slot which is fully open at one side and which has a U-shaped configuration in plan view.

As an alternative to this, it is possible for the slot to be only partially open by retaining a web arranged on the inner circumference of the body of the spacer, wherein, in this embodiment too, it is ensured that, in the case of a rig pin being screwed into the bearing housing in advance, said rig pin can be inserted into the pin recess from the only partially open side thereof.

It is also possible for the spacer to additionally be provided with a flattened portion in the region of the pin recess. In a further alternative embodiment, it is likewise possible instead of a pin recess to provide merely a flattened portion on the body of the spacer, which flattened portion is arranged diametrically opposite the sensor recess. In this embodiment, the end of the rig pin bears against the flattened portion and thereby ensures the action of the rig pin as an anti-twist facility, as is the case with the provision of a pin recess.

It is preferably possible for the pin recess to be formed with entry radii.

The rig pin may, as explained above, be designed either as an internally situated or as an externally situated cylinder-head screw.

In the case of the internally situated cylinder-head screw, the collar already explained above is provided between the screw head and the thread section in order that, in the event of a loosening of the rig pin, it is ensured that said rig pin cannot migrate in the direction of the rotor shaft and thereby damage the latter.

The invention also relates to a spacer according to Claims 9 to 13 and Claim 14 as an object which can be handled independently.

Further details, advantages and features of the present invention will emerge from the following description of exemplary embodiments on the basis of the drawing, in which:

Figure 1 shows a view of an exhaust-gas turbocharger according to the invention which can be provided with a bearing housing according to the principles of the present invention;

Figure 2 shows a horizontal section through the bearing housing according to the invention for illustrating the arrangement of a spacer with internally situated rig pin, wherein for simplicity of the illustration the bearing device is not illustrated;

Figure 3 shows a horizontal section in a perspective illustration of an embodiment of the bearing housing according to the invention, with the bearing device, the rotational speed sensor and a rig pin being illustrated, Figure 4 shows a perspective illustration of an embodiment of the spacer according to the invention,

Figure 5 shows a side view of an embodiment of a rig pin according to the invention,

Figure 6 shows a side view of an alternative embodiment of a rig pin designed as an internally situated cylinder-head screw,

Figure 7 shows an illustration, corresponding to Figure 3, of the bearing housing according to the invention,

Figure 8 shows a partial view of a further embodiment of the spacer according to the invention,

Figure 9 shows an illustration, corresponding to Figure 4, of the embodiment of the spacer according to Figure 8,

Figure 10 shows an illustration, corresponding to Figure 3, of a further embodiment of the bearing housing according to the invention, and

Figure 11 shows an end view of a third embodiment of the spacer according to the invention.

Figure 1 illustrates an exhaust-gas turbocharger 24 according to the invention which has a turbine 26 and a compressor 25 which are connected to one another via a bearing housing 1 in which a shaft 27 is mounted.

As can be seen from the horizontal sectional illustration through the bearing housing 1 in Figure 2, in which for simplicity of the illustration a bearing device 3 (see Figure 3) is not illustrated, the bearing housing 1 has a mounting bore 2 and a sensor bore 8A. A spacer 6 having a pin recess 11 at one side is arranged in the mounting bore 2, into which pin recess engages a pin head 19 of a rig pin 9, which in this case is designed as an internally situated cylinder-head screw, in order to prevent rotation of the spacer 6. The rig pin 9 has a thread section 20 which is screwed into an internal thread 10A likewise provided in the pin bore 10 of the bearing housing 1. Provided between the pin head 19 and the thread section 20 of the rig pin 9 is a collar 18 which prevents the rig pin 9 from migrating in the direction of the shaft 27 and thereby damaging the shaft 27. Figure 6 shows an enlarged side view of the rig pin 9, which is designed as an internally situated cylinder-head screw, with the pin head 19, the collar 18 and the thread section 20.

As can be seen from the perspective horizontal sectional illustration of Figure 3, the mounting bore 2 of the bearing housing 1 has a mounting device 3 with two bearing bushes 4, 5, between which the spacer 6 is arranged. Arranged diametrically opposite the rig pin 9 which is screwed into the pin bore 10, and which is designed here according to an alternative embodiment as an externally situated cylinder-head screw, is a rotational speed sensor 7 which engages into a sensor recess 8 of the spacer 6 (see Figure 4). Figure 5 shows a side view of the rig pin 9 with the free end 19' and the tliread section 20, which rig pin is designed in this embodiment as an externally situated cylinder-head screw.

As can be seen from the perspective view of Figure 4, the spacer 6 also has an oil supply bore 22 and an oil discharge bore 23 which are arranged on the circumference diametrically oppositely between the sensor recess 8, which is designed as a slot, and the pin recess 11, which is designed in this embodiment as a slot which is fully open at one side. At the open end 12 of the spacer 6, the pin recess 1 1 has in each case one entry radius 16 and 17 on each side in order to facilitate an insertion of the already screwed-in rig pin 9 into the pin recess 11 during assembly.

Figure 7 shows a perspective illustration of the bearing housing 1 with the bearing device 3 and the rotational speed sensor 7, but in said illustration, in contrast to the illustration in Figure 5, a further embodiment of the spacer 6 as illustrated in the perspective partial view of Figure 8 and in the overall view of Figure 9 is provided.

As can be seen from Figure 8, the spacer 6 in this embodiment has a pin recess 1 1 ' which is designed as an only partially open slot. Here, the cylindrical body 21 of the spacer 6 has, at its end 12, a web 13 arranged on the inner circumference 14. The web 13 is generated by a removal of material proceeding from an outer circumference 14a of the spacer 6. This ensures that the rig pin 9 which has been screwed into the bearing housing in advance can be inserted into the pin recess 1 Γ of the spacer 6 over the web 13 and prevent said spacer 6 from rotating.

Figures 10 and 1 1 show a further embodiment of the spacer 6 according to the invention. Here, as can be seen from Figure 1 1, the body 21 of the spacer 6 has a flattened portion 15 on a side of the body 21 arranged diametrically opposite the sensor recess 8. In this embodiment, to prevent the spacer 6 from rotating, the rig pin 9 bears with its head 19 against the flattened portion 15. It is likewise possible to combine a flattened portion 15 of said type with a pin recess 1 1 or 1 1 ' which is fully or partially open at one side.

To supplement the disclosure, in addition to the above written disclosure of the invention, reference is hereby explicitly made to the diagrammatic illustration thereof in Figures 1 to 1 1. LIST OF REFERENCE SYMBOLS

1 Bearing housing

2 Mounting bore

3 Bearing device

4, 5 Bearing bush

6 Spacer

7 Rotational speed sensor

8 Sensor recess

8 A Sensor bore

9 Rig pin

10 Pin bore

! OA Internal thread

1 1 Pin recess as a slot fully open at one side

1 1 ' Pin recess as an only partially open slot

12 End of the spacer

13 Web

14 Inner circumference

14A Outer circumference

15 Flattened portion

16, 17 Entry radii

18 Collar

19 Pin head

19' Free end of the externally situated cylinder-head screw for engagement into the pin recess 1 1 , 1 Γ

20 Thread section

21 Cylindrical body

22 Oil supply bore

23 Oil discharge bore

24 Exhaust-gas turbocharger

25 Compressor

26 Turbine

27 Shaft

Claims

1. A bearing housing (1) of an exhaust-gas turbocharger (24),

having a mounting bore (2);

- having a bearing device (3) which has two bearing bushes (4, 5) which are arranged in the mounting bore (2) and between which a spacer (6) is arranged;

having a rotational speed sensor (7) which engages into a sensor recess (8) of the spacer (6); and

having a rig pin (9) which is screwed into a pin bore (10) and which engages with its pin head (19) into a pin recess (1 1) of the spacer (6);

wherein

the pin recess (1 1) is designed as a slot which is open to one end (12) of the spacer (6).

2. The bearing housing as claimed in claim 1, wherein the pin recess (1 1) is designed as a slot which is fully open at one side.

3. The bearing housing as claimed in claim 1, wherein the pin recess (1 1 ) is designed as an only partially open slot (1 Γ), such that a web (13) arranged on the inner circumference (14) of the spacer (6) is retained.

4. The bearing housing as claimed in one of claims 1 to 3, wherein the spacer (6') has a flattened portion (15) in the region of the pin recess ( 1 1 ; 11 ').

5. The bearing housing as claimed in claim 1 or 2, wherein the pin recess (11) is provided with entry radii (16, 17).

6. The bearing housing as claimed in one of claims 1 to 5, wherein the rig pin (9) is designed as a cylinder-head screw with a collar (18) between the pin head (19) and a thread section (20).

7. The bearing housing as claimed in claim 6, wherein the rig pin (9) is designed as an internally situated cylinder-head screw.

8. The bearing housing as claimed in one of claims 1 to 5, wherein the rig pin (9) is designed as an externally situated cylinder-head screw.

9. A spacer (6, 6') of an exhaust-gas turbocharger bearing device (3) liaving a cylindrical body (21);

having a sensor recess (8) on one side of the body (21);

having a pin recess (1 1 ; 1 Γ) on a side of the body (21) arranged diametrically opposite the sensor recess (8); and

having an oil supply bore (22) and an oil discharge bore (23) arranged diametrically opposite said oil supply bore (22),

wherein

the pin recess (11) is designed as a slot which is open to one end (12) of the body (21).

10. The spacer as claimed in claim 9, wherein the pin recess (1 1) is designed as a slot which is fully open at one side.

11. The spacer as claimed in claim 9, wherein the pin recess (1 Γ) is designed to be partially open such that a web (13 ) arranged on the inner circumference (14) of the body (21) is retained.

12. The spacer as claimed in one of claims 9 to 11, wherein the body (21) has a flattened portion (15) in the region of the pin recess (1 1 ; 1 Γ).

13. The spacer as claimed in one of claims 9 to 12, wherein the pin recess (1 1) is provided with entry radii (16, 17).

14. A spacer (6) of an exhaust-gas turbocharger bearing device (3),

having a cylindrical body (21);

having a sensor recess (8) on one side of the body (21); and

wherei

a flattened portion (15) on a side of the body (21) is arranged diametrically opposite the sensor recess (8).