EP2603702A1

EP2603702A1 - Flow compressor, in particular for the supercharging of an internal combustion engine

Info

Publication number: EP2603702A1
Application number: EP12715595.0A
Authority: EP
Inventors: Christian GROTHE
Original assignee: Voith Patent GmbH
Current assignee: Voith Patent GmbH
Priority date: 2011-04-29
Filing date: 2012-04-07
Publication date: 2013-06-19
Also published as: JP2014512485A; DE102011019006B3; CN103154525A; WO2012146344A1

Abstract

A flow compressor, in particular for the supercharging of an internal combustion engine, having a compressor housing; having a compressor rotor which is rotatably mounted in the compressor housing; having an inflow duct for the medium to be compressed, which inflow duct extends in the flow direction of the medium to be compressed from a compressor inlet to the compressor rotor; having a recirculation duct for the medium to be compressed, which recirculation duct branches off from the inflow duct in the region of the compressor-rotor-side end of the inflow duct and opens out in the inflow duct in the region of the compressor-inlet-side end; having a sound shielding ring which is inserted in the inflow duct and/or in the recirculation duct in the region of the compressor-inlet-side end in order to shield against sound waves of the medium to be compressed which flows back via the recirculation duct; wherein the sound shielding ring is inserted in a positively locking manner in the compressor housing by means of a snap-action connection. The invention is characterized in that - the sound shielding ring has a multiplicity of detent projections which engage into an undercut of the compressor housing; - the sound shielding ring has a multiplicity of tongues which are connected to a circumferentially encircling annular main body and which are provided with the detent projections, and the tongues project from the compressor-inlet-side end into the recirculation duct in the direction of the compressor rotor.

Description

Flow compressor, in particular for charging an internal combustion engine

The present invention relates to a flow compressor, in particular for charging an internal combustion engine, in detail according to the preamble of claim 1.

Flow compressors of the generic type are driven for example by means of an exhaust gas turbine, wherein the flow compressor and the

Exhaust gas turbine can be arranged on a common shaft to form a turbocharger. However, there is also a mechanical drive of the flow compressor, for example by means of the crankshaft of the

Internal combustion engine to be charged with the flow compressor into consideration. Finally, the present invention is also in

Flow compressors outside the charging of internal combustion engines applicable.

For map spread of the compressor map, it is known in the housing of the compressor at the compressor rotor end of the inflow channel for the medium to be compressed, in particular air, to introduce so-called recirculation slots, via which a part of the medium to be compressed, already from a compressor inlet through the inflow into the vicinity of

Compressor impeller has flowed, flows outside the inlet channel in the direction of the compressor inlet side end of the inflow and mixed there with subsequent flowing into the inflow channel medium. For this purpose, the recirculation slots are outside of the inflow channel

extending channel or a plurality of such channels with one or more orifices directly in the compressor inlet in the

Inlet channel open or in the flow direction of the medium to be compressed behind the compressor inlet, however, with sufficient distance from the

Rezirkulationsschlitzen. The sequence of recirculation slots, the channel outside the inflow channel for returning the medium to be compressed and the mouth or mouths is also referred to as a recirculation channel. Due to the opposite direction of flow of the medium to be compressed in the inflow channel opposite flow direction of the medium in

Recirculation channel there is a risk of unwanted sound propagation out of the inlet side of the compressor. A known measure therefore envisages the use of a sound shielding ring in the inflow channel or in the recirculation channel in the region of the end of the compressor inlet which separates the

To prevent or attenuate the propagation of sound waves out of the compressor inlet. Such Schallabschirmring is conventionally in the

Inlet duct inserted at the compressor inlet and secured by a bolted flange against falling out. The disadvantage is that the retrofitting of existing flow compressors with such Schallabschirmring not or only by reworking or replacement of components of the housing and / or the flange is possible, resulting in undesirable costs. Furthermore, the design of such a Schallabschirmrings and the design of the receiving components of the compressor housing or the flange for the individual case must be adapted to each other.

In the figure 1 is an axial section through a flow compressor with a Schallabschirmring 10, between the compressor housing 1 and a

Connection flange 2 is clamped, shown.

For prior art reference is made to the following documents:

DE 198 23 274 Cl

DE 42 12 653 B4 US Pat. No. 7,624,575 B2

WO 2006/090152 Al

EP 0 913 585 Al

WO 2011/044344 A2

US 5,333,990 A.

The present invention is based on the object, a

Specify flow compressor with a Schallabschirmring said type, in which the installation of the Schallabschirmrings particularly cost-effective, safe and advantageous subsequently possible.

The object of the invention is achieved by a flow compressor with the features of claim 1. An alternative embodiment according to the invention is described in claim 9. In the dependent claims advantageous and particularly expedient embodiments of the invention are given.

The flow compressor according to the invention, in particular as

Flow compressor for charging an internal combustion engine, for example driven via an exhaust gas turbine or mechanically driven via the

Internal combustion engine itself, is executed, has a housing and a rotatably mounted in the housing compressor impeller. Furthermore, an inflow channel for the medium to be compressed, usually air, provided in

Flow direction of the medium to be compressed from a compressor inlet extends to the compressor impeller.

According to the invention, a recirculation channel is provided for the medium to be compressed. The recirculation channel branches off, as described above, in the region of the compressor impeller-side end from the inflow channel and opens in the region of the compressor inlet-side end in the inflow channel, wherein hereunder both a Mouth in the compressor inlet and behind the compressor inlet in

Intake channel is to be understood.

Furthermore, a Schallabschirmring is provided, which is in the range of

Compressor inlet side end is inserted in the inflow and / or in the recirculation channel to shield sound waves of the flowing back via the recirculation channel to be compressed medium. The sound shielding ring can

For example, be inserted into the inflow and / or recirculation, starting from the compressor inlet.

According to the Schallabschirmring is now inserted by means of a snap connection form fit in the housing of the compressor. Such

Snap connection is achieved by the elasticity of the Schallabschirmrings and / or associated therewith the region of the housing, wherein when inserting the Schallabschirmrings one of the two joining parts or both joining parts

(Schallabschirmring and associated area of the housing) elastic

deformed / deformed, so that there is a positive undercut releasable or non-detachable connection. The undercut causes the Schallabschirmring form-fitting against pushing out by the in

Recirculation channel flowing back medium or by the flowing medium or vibrations in the inlet channel and the like is reliably prevented.

According to the invention, a plurality of locking projections on the

Schallabschirmring provided which engage in corresponding undercuts of the housing or a circumferential or over a portion of the circumference circumferential undercut of the housing.

Of course, it is also possible to additionally provide such a latching projection or a plurality of latching projections in the housing itself. The one or more locking projections are usually positioned on an elastically resilient portion of the Schallabschirmrings and / or the housing and may additionally or alternatively also be made of elastic material itself.

It is particularly favorable if the undercuts in the housing are formed by one or more slits extending at least partially in the radial direction, which form the branch of the recirculation channel in the region of the compressor rotor-side end of the inflow channel. Such slots are also referred to as recirculation slots.

The Schallabschirmring has, according to an embodiment of the invention, a plurality of circumferential at an over the circumference annular

Main body connected tongues, which are provided with the latching projections, in particular at its the base body facing away from the free end. Accordingly, the tongues can be elastically deformable radially outwards and / or inwardly to produce the desired elasticity, thus enabling the latching projections to slide over the region of the housing delimiting the undercut when the sound shielding ring is inserted.

For example, the tongues may protrude into the recirculation channel from the compressor inlet side end in the direction of the compressor inlet and the

Wear locking projections on their free, the compressor impeller end facing.

To achieve an effective sound shielding, the

Projecting Schallabschirmring in the region of the compressor inlet radially from the outside into the inflow, in particular with its annular body, which the protruding, in particular in the radial direction elastic

bears yielding tongues. An embodiment of the invention provides that both the

Inlet passage and the recirculation passage extend in the direction of the rotational axis of the compressor impeller to form an axial-axial compressor or an axial-radial compressor. The extension of the recirculation channel is guided at least insofar in the axial direction as the return of the recirculated medium takes place in the direction of the compressor inlet.

The Schallabschirmring can in particular be made in one piece, advantageously urgeformt one piece.

It is advantageous if the Schallabschirmring made of plastic or sheet metal or steel, at least partially or entirely made of spring steel, the latter to achieve the desired elasticity.

The Schallabschirmring can breakthroughs, especially in his in

Have longitudinal direction of the inlet channel extending portion to the

To increase flow cross-section for the recirculated medium. This is especially true for a closed over the circumference area, for example, instead of individual tongues.

According to an alternative embodiment of the invention is the

Schallabschirmring poured into the compressor housing. This can be done by a prior to or during the casting of the compressor housing inserted into the mold insert (inlay) or the Schallabschirmring can be made by the potting compound itself, that is, compressor housing and

Schallabschirmring are made of the same material. When using an insert this can for example be made of plastic again. However, other materials are also considered. Regarding the Extent of the Schallabschirmrings in the flow compressor applies what was previously said to the embodiment with snap connection.

Instead of casting or pouring an insert to the compressor housing or in the compressor housing, the casting of a

Insert on a connected to the compressor housing, in particular bolted flange, in particular connecting flange for the air to be compressed, or pouring into this be provided to the

Sound shielding produce.

The invention will be described by way of example with reference to exemplary embodiments.

Figure 2 shows a first embodiment with a means of a

Snap connection form-fitting inserted into the compressor housing Schallabschirmring;

Figure 3 is a molded on the compressor housing Schallabschirmring;

Figure 4 a cast in the compressor housing as an insert

Sound shield ring.

In the figure 2 is in an axial section through the compressor housing 1 the

Compressor impeller 3, which rotates on the compressor shaft 4, shown. In the area of the compressor inlet 5, a connection flange 2 is connected to the compressor housing 1 to an air line for the air to be compressed as

Compressor (not shown) to connect to the compressor housing 1. The areas leading the compressor medium (air) are shown in black, see the suction-side flow guide region 6 and the pressure-side flow guide region 7. The suction-side flow guide region 6 comprises the inflow channel 8 extending from the compressor inlet 5 to the compressor impeller 3 and the recirculation channel 9 outside, here radially outside, of

Inlet 8 from the compressor impeller end to the

compressor inlet side end of the inflow channel 8 extends. To connect the recirculation 9 at the inflow 8 are in the range of

Compressor wheel-side end of the inflow channel 8 Rezirkulationsschlitze 11 provided in the compressor housing 1, via which the medium to be compressed flows from the inflow passage 8 in the recirculation passage 9. At the

In the compressor inlet end of the inflow channel 8 or in the region thereof are provided openings 12, via which the medium to be compressed flows from the recirculation channel 9 into the inflow channel 8. The

In the present embodiment, a Schallabschirmring 10 is provided in the region of the compressor inlet 5, which in the embodiment shown an annular base body 13 integrally connected thereto, in the axial direction of the compressor (in Direction of the compressor shaft 4) extending tongues 14 has. This Schallabschirmring 10 is shown in Figure 2a again in an axial section and in Figure 2b in a plan view in the axial direction. Especially here it is clear that the tongues 14 carry at their free axial end latching projections 15, which are intended to be in the recirculation slots 11 of the

Compressor housing 1 to lock. In the present case, the sound shielding ring 10 has an annular base body 13 closed over the circumference with three tongues 14 connected thereto. Of course, the number of Tongues 14 can be changed or a circumferential over the entire circumference tongue 14 may be provided. Such should have breakthroughs for the compressor medium. The provision of locking projections 15 which engage in the recirculation slots 11, and thus project radially inwardly from the tongues 14, is favorable because the recirculation slots 11 for branching the recirculating medium are usually provided when a Schallabschirmring 10 is required. Thus, for mounting the Schallabschirmrings 10 special modifications to the compressor housing 1 can be saved and retrofitting an existing compressor with a Schallabschirmring 10 according to the invention is easily possible, especially without post-processing of the compressor housing 1. Figure 3 shows an alternative embodiment of the invention, wherein the Schallabschirmring 10 is molded on the compressor housing 1. Instead of casting directly on the compressor housing 1, it would alternatively be possible to cast it onto the connecting flange 2. 4 shows an embodiment with a Schallabschirmring 10, which is cast in the form of an insert in the compressor housing 1. Here too, pouring the insert into the connecting flange 2 would be an alternative option.

LIST OF REFERENCE NUMBERS

1 compressor housing

2 connection flange

3 compressor impeller

4 compressor shaft

5 compressor inlet

6 suction-side flow guidance area

7 pressure-side flow guidance area

8 inflow channel

9 recirculation channel

10 sound shielding ring

11 recirculation slots

12 mouths

13 basic body

14 tongues

15 locking projection

Claims

claims

1. flow compressor, in particular for charging a

Combustion engine,

1.1 with a compressor housing (1);

1.2 with a Verdichteria ufrad (3) which is rotatably mounted in the compressor housing (1);

1.3 with an inflow channel (8) for the medium to be compressed, in the flow direction of the medium to be compressed by a

Compressor inlet (5) extends to the compressor impeller (3);

1.4 with a recirculation channel (9) for the medium to be compressed, which branches off in the region of the compressor impeller end from the inlet channel (8) and in the region of the compressor inlet end in the

Inflow channel (8) opens;

1.5 with a Schallabschirmring (10), in the range of

Compressor inlet side end in the inlet channel (8) and / or in the

Rezirkulationskanal (9) is used to shield the sound waves of the back over the recirculation channel (9) to be compressed medium; in which

.6 the Schallabschirmring (10) is positively inserted by means of a snap connection in the compressor housing (1);

characterized in that

the Schallabschirmring (10) has a plurality of latching projections (15) which in an undercut of the compressor housing (1)

, intervention;

the sound shielding ring (10) has a plurality of tongues (14) connected to a peripheral annular body (13) provided with the detent projections (15) and the tongues (14) from the compressor inlet side end in the direction of

Compressor impeller (3) protrude into the recirculation passage (9).

2. flow compressor according to claim 1, characterized in that the undercut by one or more at least partially in

Radial direction extending recirculation slots (11) in the compressor housing (1) is formed, which form the junction of the recirculation channel (9) in the region of the compressor impeller-side end of the inflow channel (8).

3. flow compressor according to one of claims 1 or 2, characterized

in that the latching projections (15) are provided on the free end of the tongues (14) facing away from the base body (13).

4. flow compressor according to one of claims 1 to 3, characterized

characterized in that the Schallabschirmring (10) in the region of

Compressor inlet (5) protrudes radially from the outside into the inflow passage (8), in particular with its annular base body (13).

5. flow compressor according to one of claims 1 to 4, characterized

characterized in that the inflow channel (8) and the

Rezirkulationskanal (9) in the direction of the axis of rotation of the compressor impeller (3) extend.

6. flow compressor according to one of claims 1 to 5, characterized

in that the sound shielding ring (10) completely covers the recirculation channel (9) on the end facing the compressor inlet (5).

7. flow compressor according to one of claims 1 to 6, characterized

characterized in that the Schallabschirmring (10) is made in one piece.

8. flow compressor according to one of claims 1 to 7, characterized in that the Schallabschirmring (10) is made of plastic.

9. flow compressor, in particular for charging a

Combustion engine,

9.1 with a compressor housing (1);

9.2 with a compressor impeller (3) which is rotatably mounted in the compressor housing (1);

9.3 with an inflow channel (8) for the medium to be compressed, extending in the flow direction of the medium to be compressed by a

Compressor inlet (5) extends to the compressor impeller (3);

9.4 with a recirculation channel (9) for the medium to be compressed, which branches off in the region of the compressor impeller end from the inflow channel (8) and in the region of the compressor inlet end in the

Inflow channel (8) opens;

.5 with a Schallabschirmring (10), in the range of

Compressor inlet side end in the inlet channel (8) and / or in the

Rezirkulationskanal (9) is provided to shield the sound waves of the back over the recirculation passage (9) to be compressed medium;

characterized in that

.6 the Schallabschirmring (10) in the compressor housing (1) or connected to this flange (2) made of the same material as the compressor housing (1) or the flange (2) or in the form of an insert is cast.