EP3559469A1

EP3559469A1 - Scroll compressor

Info

Publication number: EP3559469A1
Application number: EP17825232.6A
Authority: EP
Inventors: Frank Obrist; Christian SCHMÄLZLE; Christian Busch
Original assignee: OET GmbH
Current assignee: OET GmbH
Priority date: 2016-12-22
Filing date: 2017-12-22
Publication date: 2019-10-30
Also published as: WO2018115424A1; DE102016125384A1

Abstract

A scroll compressor having a movable displacer spiral (13), which is connected to an eccentric bearing (16) for conjoint rotation and which engages in a stationary counterspiral (14) in such a way that radially inwardly moving chambers are formed between the windings of the displacer spiral (13) and the counterspiral (14), wherein the counterspiral (14) is situated in a housing (10) with a peripheral wall (11) that is cylindrical at least in portions, wherein the outside diameter of the peripheral wall (11) is larger than an outside diameter of the stationary counterspiral (14) and at most 110% of the outside diameter of the stationary counterspiral (14).

Description

Scroll compressor

description

The invention relates to a scroll compressor according to the preamble of

Claim 1. Furthermore, the invention relates to an exhaust gas purification system and a motor vehicle with such a scroll compressor. A scroll compressor of the type mentioned is known for example from JP 2006/144635 A.

JP 2006/144635 A describes a scroll compressor which is used as a compressor for a motor vehicle air conditioning system. The known scroll compressor comprises a movable displacement spiral which is mounted eccentrically. The Verdrängerspirale engages in a stationary counter-spiral, which in one

partially cylindrical housing is arranged. With the movement of the displacement spiral arise between the positive displacement spiral and the counter-spiral inwardly migrating chambers, leading to a compression of the

Scroll compressor flowing carbon dioxide leads. The well-known scroll compressor has a solid construction. In particular, the housing is equipped with a strong peripheral wall to withstand the high pressures in the CG air conditioning circuit. Disadvantages are

in particular the high external dimensions and the high weight of the known scroll compressor.

In modern motor vehicles, it is necessary to carry out an exhaust gas aftertreatment in order to be able to meet the increasing legal requirements for permissible pollutant emissions. In particular, due to the decreasing limit values, it is often necessary to use a soot particle filter even in vehicles with a directly injecting gasoline engine. Of the

Particulate filter must be regenerated at regular intervals or

be reprocessed. This is usually done by burning out or cleaning the particulate filter while driving. This will be high

Temperatures needed. These can be achieved by injecting additional oxygen into the exhaust gas. Insofar there is a need for one Compressor, which additionally introduces oxygen into the exhaust gas, thus ensuring effective regeneration or reprocessing of the particulate filter.

The object of the invention is to develop a scroll compressor of the type mentioned in such a way and adapt that this as

Compressor is suitable for supplying oxygen into an exhaust gas stream.

In particular, the scroll compressor should have a compact design and low weight in order to be easily integrated into existing exhaust systems can. Another object of the invention is to provide an exhaust gas purification system and a motor vehicle with such a scroll compressor.

This object is achieved with respect to the scroll compressor by the subject-matter of claim 1, in view of the exhaust gas purification system by the subject-matter of claim 13 and H inblick on the motor vehicle by the subject-matter of claim 15.

Thus, the invention is concretely based on the idea of specifying a scroll compressor with a movable displacement spiral, wherein the displacement spiral is rotatably connected to an eccentric bearing. The displacement spiral engages in a stationary counter-spiral so that between the turns of

Verdrängerspirale and the counter-spiral radially inwardly migrating chambers are formed. The counter-spiral is arranged in a housing with an at least partially cylindrical peripheral wall. According to the invention, it is provided that an outer diameter of the circumferential wall is at most 10%, in particular at most 8%, in particular at most 6%, larger than an outer diameter of the counter-spiral.

The invention has the advantage that a compact design with low weight is ensured by adjusting the ratio between the outer diameter of the peripheral wall of the housing and the outer diameter of the counter-spiral. This is especially true when scaling the

Scroll compressor according to the invention. As far as that predicted

In any case, it is ensured that the scroll compressor is particularly compact. At the same time, compliance with the diameter ratio ensures that the scaling of the Scroll compressors and thus possibly associated higher pressures in the compressor circuit sufficient stability of the scroll compressor is.

For common dimensions of scroll compressors, in particular for use as a compressor in an exhaust gas purification system, it is expedient if the

Peripheral wall has a wall thickness which is between 1.5 mm and 4.5 mm, in particular between 2 mm and 3.5 mm, in particular 3 mm. It has been found that such wall thicknesses are sufficient to ensure efficient operation of the scroll compressor, to ensure the robustness of the scroll compressor and at the same time bring about a compact design with low weight.

With regard to the compact dimensions of the scroll compressor is preferably provided when the housing has an outer diameter of at most 130 mm, in particular at most 120 mm, in particular at most 110 mm. With these outer dimensions it is ensured that the scroll compressor can be well integrated into existing installation spaces of a motor vehicle. This avoids a costly redesign of vehicle components. In a particularly preferred embodiment of the invention it is provided that the housing is pot-shaped, in particular as a one-piece deep-drawn part is formed. On the one hand, the cup-shaped design of the housing facilitates the assembly of the scroll compressor and, on the other hand, reduces the necessary components, so that the scroll compressor as a whole can be manufactured inexpensively. A further improvement in terms of manufacturing costs and manufacturing costs is achieved in that in preferred

Embodiments of the invention, the housing has a bottom which is integrally connected to the peripheral wall. In other words, the bottom can be formed integrally in the cup-shaped housing. Specifically, the bottom can be formed by a thermoforming process on the housing.

With regard to a particularly simple integration of the scroll compressor in an exhaust gas purification system is advantageously provided that the ground a

Having fluid inlet which is coaxial with the peripheral wall. This ensures, on the one hand, that air flowing into the scroll compressor is conducted directly into the scroll compressor without any prior deflection can be. On the other hand, it is achieved by the coaxial arrangement of the fluid inlet that the scroll compressor can be easily integrated into an air hose line. A further improvement of the installation possibility of the scroll compressor is achieved in preferred embodiments in that the housing has a housing cover, which has a fluid outlet, wherein the fluid outlet is aligned coaxially to the peripheral wall. In other words, the fluid outlet may be coaxially aligned with the fluid inlet. Thus, a flow path is generated by the scroll compressor, the input side leads coaxially into the scroll compressor and the output side leads out coaxially from the scroll compressor. In this way, the scroll compressor can be integrated particularly easily into existing hose lines or pipelines. An additional deflection of hose lines is avoided, so that overall the scroll compressor is particularly compact integrated into an exhaust gas purification system.

The housing cover of the housing, in particular of the cup-shaped housing, may preferably be fixedly connected to the peripheral wall of the housing.

In particular, the housing cover can be welded to the circumferential wall. A solid, in particular sealing connection, is expedient in order to achieve a high efficiency of the compressor power of the scroll compressor.

Furthermore, in a preferred Ausführu ngsform of the invention

Scroll compressors provided that the eccentric bearing is connected to a shaft which is rotatably mounted in a shaft bearing. The shaft bearing is

preferably within the housing, in particular at the bottom of the housing arranged. The shaft bearing may in particular be aligned coaxially with a fluid inlet of the housing. The inlet-side shaft bearing may be disposed in a carrier that spans the bottom via the fluid inlet. The carrier may have a plurality of through openings, which are traversed by air. The arrangement of the inlet-side shaft bearing at the bottom of the housing also ensures a compact design, in particular small outer dimensions in the longitudinal axial direction, sure. In a further preferred embodiment of the invention

Scroll compressors is provided that the displacement spiral and / or the counter-spiral are formed from plastic. The use of a

Plastic material is on the one hand appropriate to the weight of the

Reduce scroll compressors. On the other hand, it is for the intended

Application as air compressor, where no high pressures are expected, sufficient. The use of a plastic material for the Verdrängerspirale and / or the counter-spiral is also advantageous because of the

Plastic material, the displacement spiral and the counter-spiral can slide well on each other. Friction losses are thus reduced. At the same time, such a designed scroll compressor is characterized by a low noise.

The housing and / or the housing cover, however, may be formed of steel and / or aluminum. The use of a metal increases the overall stability of the scroll compressor. In particular, the scroll compressor is thus protected against rockfalls to which the scroll compressor is possibly exposed depending on the installation in a motor vehicle. Particularly advantageous is the use of aluminum as a material for the housing, since this is corrosion resistant and very light.

The scroll compressor can be run dry. This reduces the maintenance of the scroll compressor. In particular, a separate lubrication of the scroll compressor is unnecessary. This reduces the operating costs of the

Scroll compressor.

In preferred embodiments of the invention it is provided that four inwardly migrating chambers are formed between the turns of the positive displacement spiral and the counter-spiral. Overall, therefore, both the

Verdrängerspirale, as well as the counter-spiral in each case two spirals, wherein the two spirals of the displacement spiral engage in the two spirals of the counter-spiral. As a result, a total of four migratory chambers are formed between the spirals. In other words, the scroll compressor is preferably designed to be double-flowed. A subsidiary aspect of the invention relates to an exhaust gas purification system of a gasoline engine with a scroll compressor described above. In the exhaust gas purification system may preferably be provided that the

Scroll compressor is arranged in front of a soot particle filter and / or in front of a catalyst, so that by means of the scroll compressor, a secondary air flow into an exhaust gas stream upstream of the soot particle filter and / or upstream of the catalyst can be introduced. The scroll compressor is used in this constellation as

Air compressor, which makes it possible in the exhaust gas flow in addition to air, and thus to inject oxygen. In this way, the exhaust gas is enriched with oxygen and only then enters the soot particle filter. Within the soot particle filter, the oxygen can exert its effect by the

Increase combustion temperatures in the soot particle filter. Thus, the soot particle filter is burned or regenerated. In the context of the present application, a motor vehicle with a gasoline engine and a previously described exhaust gas cleaning system is also disclosed and claimed.

The invention is explained in more detail below with reference to an embodiment with reference to the accompanying schematic drawings. Show in it

Fig. 1 is a longitudinal sectional view through an inventive

Scroll compressor according to a preferred embodiment;

Fig. FIG. 2 is a cross-sectional view through the compressor assembly including the positive displacement spiral and the counter-spiral of the scroll compressor of FIG. 1; and FIG. 3 to 6 are each a longitudinal sectional view through an inventive

Scroll compressor according to a preferred embodiment in different phases of a preferred manufacturing process.

In Fig. 1, a scroll compressor is shown in a longitudinal sectional view. The scroll compressor comprises a movable displacement spiral 13, which engages in a counter-spiral 14. The displacement spiral 13 and the counter-spiral 14 together form a compressor assembly 32. The displacement spiral 13 is rotatably connected to an eccentric 16. The eccentric bearing 16 is connected eccentrically to a shaft 15 by means of a bearing pin 16a. The total eccentric connection between the displacement spiral 13 and the shaft 15 ensures that the displacement spiral 13 within the housing 10 orbits in the stationary counter-spiral 14.

The shaft 15 is in an inlet side shaft bearing 17 and a

outlet side shaft bearing 25 stored. The exhaust side shaft bearing 25 is disposed in a center plate 24 that separates the compressor assembly 32 from a drive assembly 31. The drive assembly 31 includes a

Electric motor 18 having a stationary stator 18a. Within the stationary stator 18a rotates a rotor 18b, which is advantageously arranged on the shaft 15 or formed as part of the shaft 15. Specifically, the shaft 15 may form a rotor 18b of the electric motor 18. For this purpose, the shaft 15 in the region of the stator 18a on the circumference distributed permanent magnets. The electric motor 18 is so far preferably designed as a brushless DC motor. The shaft 15 has, at an inlet side end, a journal 16b which extends into the inlet side shaft bearing 17. The bearing pin 16 b is formed integrally with the shaft 15. The inlet-side shaft bearing is held in a carrier 26. The carrier 26 spans over a fluid inlet 21 of a housing 10 of the scroll compressor.

Concretely, the scroll compressor has a housing 10, which may in particular be cup-shaped. The housing 10 comprises an at least partially cylindrical peripheral wall 11 and a bottom 12. The bottom 12 is preferably formed integrally with the peripheral wall 11. However, it is also possible that the bottom 12 and the peripheral wall 11 form separate components which are fixedly connected together to form the housing 10.

Within the housing 10, in particular in a housing interior 30, the drive assembly 31, the compressor assembly 32 and the middle plate 24 are arranged. In particular, the electric motor 18 is disposed within the housing 10.

The housing 10 has a fluid inlet 21 in the region of the bottom 12. The fluid inlet 21 is preferably arranged coaxially to the circumferential wall 11 and preferably designed as a connecting piece. Coaxially with the fluid inlet 21, the shaft 15 is also aligned. The fluid inlet 21 allows the supply of a fluid, in particular of air, into the housing interior 30

Fluid inlet 21 is formed in the bottom 12 of the housing 10. In the area of the bottom 12, the carrier 26 is arranged in the housing interior 30. The carrier 26 has at least one passage opening 26a, so that fluid flowing in via the fluid inlet 21 can flow into the housing interior 30, in particular into a suction space 30a. The suction space 30 a extends from the bottom 12 to the center plate 24 and receives mainly the electric motor 18.

The housing 10 has a total of a motor portion 10 a and a

Compressor section 10b on. The motor portion 10a extends in

Substantially, from the bottom 12 to the middle plate 24. The motor portion 10a includes the suction space 30a of the housing 10 in this respect. The motor portion 10a integrally merges into the compressor portion 10b, in which the center plate 24 and the compressor assembly 32 is disposed. The compressor section 10b has an outer diameter which is larger than the outer diameter of the motor section 10a. In other words, the housing 10 follows the

Outer contours of the compressor assembly 32 and the drive assembly 31 to ensure the most compact external dimensions.

The peripheral wall 11 of the housing 10 is at least partially cylindrical. In particular, the peripheral wall 11 is in

Compressor section 10b formed cylindrical. In the compressor section 10b, the peripheral wall 11 of the housing 10 has an outer diameter which is at most 10% larger than the outer diameter of the counter-spiral. As shown in FIG. 1 is clearly visible, the wall thickness of the peripheral wall 10 is comparatively small, whereby the scroll compressor receives a total of a compact design. The housing 10 is closed at the end with a housing cover 20, wherein the housing cover 20 has a fluid outlet 22. The fluid outlet 22 is coaxial with the circumferential wall 11, in particular coaxially with the fluid inlet 21, aligned. The fluid outlet 22 is formed by a connecting piece, which is formed integrally with the housing cover 20. The housing cover 20 preferably extends through the housing interior 30 and abuts against an inner circumferential surface of the circumferential wall 11. The housing cover 20 may in particular be welded to the circumferential wall 11 of the housing 10. In Fig. 1 is also clearly visible that in the region of the motor portion 10a of the housing 10 outside the housing 10 further components are arranged.

In particular, an electronics compartment 19 is provided, which is the electronic

Control of the scroll compressor receives. On one side of the housing 10 opposite the electronics compartment 19, cooling fins 23 are provided in the region of the motor section 10a of the housing 10. The electronics chamber 19 and the cooling fins 23 each extend radially so far that their

Outer peripheral surfaces with the outer peripheral surface of the peripheral wall 11 in the compressor section 10b is aligned. Overall, the scroll compressor thus receives a uniform outer diameter.

In Fig. 1, the housing 10 with the compressor section 10b and the motor section 10a and the bottom 12 is overall pot-shaped. The housing 10 may simply be designed as a deep-drawn part. The fluid inlet 21 is preferably integral with the bottom 12

formed. Likewise, the bottom 12 for receiving the carrier 26 a

Recess 27 have. The recess 27 preferably passes directly into the fluid inlet 21.

In Fig. 2 is a cross-sectional view through the compressor assembly 32, in particular the displacement spiral 13 and the counter-spiral 14. The illustration according to FIG. FIG. 2 shows a view from above of a dome 28 of the displacement spiral 13 which extends over the eccentric bearing 26.

As shown in FIG. 2 is clearly visible, the displacement spiral 13 and the

Gegenspirale 14 each two spiral turns on. The spiral turns of the displacement spiral 13 and the counter-spiral 14 engage each other, so that at Movement of the displacement spiral 13 migratory chambers are formed. The traveling chambers convey fluid entering the scroll compressor from the fluid inlet 21 to the fluid outlet 22

Compressor assembly 32 four migratory chambers formed. Of the

Scroll compressor therefore has a double-flow design.

Hereinafter, a preferred method for manufacturing or mounting the scroll compressor with reference to FIG. 3 to 6 explained in more detail: For the preparation of the scroll compressor first the housing 10th

provided, wherein the housing 10 is preferably cup-shaped. The production of the housing 10 can be done for example by a deep-drawing process. In this case, the bottom 12 and the fluid inlet 21 are preferably formed directly with the production of the housing 10. Further, in the deep-drawing process in the housing 10, a recess 27 may be formed, which extends annularly around the fluid inlet 21. Alternatively, it can be provided that the bottom 12 is provided as a separate component and with the

Peripheral wall 11 is firmly connected. The recess 27 is preferably integrally formed in the bottom.

In the housing 10, the inlet-side shaft bearing 17 is inserted with the carrier 26. In this case, the carrier 26 is positioned in the recess 27. Further, the stator 18 a of the electric motor 18 is inserted or inserted into the motor portion 10 a of the housing 10. As can be clearly seen in FIG. 3, a further subassembly comprising the shaft 15 and the rotor 18 b is also guided coaxially via a cover opening 33 of the housing 10 into the housing interior 30. In this case, the bearing pin 16 b is inserted into the inlet-side shaft bearing 17, as shown for example in Fig. 4. Further, the center plate 24 is inserted coaxially via the lid opening 33 in the housing 10.

It is preferably provided that the central plate 24 with the shaft 15 and the rotor 18 b forms a compact, preassembled unit, which is uniformly inserted into the housing 10. This facilitates the assembly of the scroll compressor, since in this way an alignment of the shaft 15 to the outlet side

Shaft bearing 25 does not have to be within the housing 10. In a next step, the compressor spiral 13 is inserted into the housing interior 30 via the cover opening 33. This is the Dom 28 with the

Eccentric bearing 16 mounted on the bearing pin 16a of the shaft 15 (Fig. 4).

Subsequently, the counter-spiral 14 via the lid opening 33 in the

Housing interior 30 introduced coaxially. The compressor spiral 13 and the counter-spiral 14 are aligned so that their spiral turns

mesh. In this way, the compressor assembly 32 within the housing 10, in particular in the compressor section 10b, composed. The counter-spiral 14 is preferably press-bonded to the peripheral wall 11 of the housing 10 simultaneously with insertion into the housing 10.

Concretely, the displacer coil 14 enters the compressor section 10b of FIG

Housing 10 is pressed. After complete assembly of the internal components of the scroll compressor within the housing interior 30 of the housing cover is inserted into the lid opening 33. The housing cover 20 can be pressed into the cover opening 33 with the housing 10, in particular the peripheral wall 11 (FIG. 5). In a final step, in particular for sealing and stabilizing the connection between the housing cover 20 and the housing 10, a

Welding process in which the housing cover 20 is welded to the housing 10. A welding process is shown in FIG. 6 represented by a flash.

LIST OF REFERENCE NUMBERS

10 housing

10a engine section

10b compressor section

11 peripheral wall

12 floor

13 displacement spiral

14 counter-spiral

15 wave

16 eccentric bearings 16a bearing pin

16b bearing journal

17 inlet side shaft bearing

18 electric motor

18a stator

18b rotor

19 electronics room

20 housing cover

21 fluid inlet

22 fluid outlet

23 cooling fins

24 middle plate

25 Outlet shaft bearing

26 carriers

26a passage opening

27 deepening

28 Dom

30 housing interior

30a intake

31 drive module

32 compressor assembly

33 lid opening

Claims

claims

Scroll compressor with a movable Verdrängerspirale (13) which is rotatably connected to an eccentric bearing (16) and engages in a stationary counter-spiral (14) such that between the turns of the Verdrängerspirale (13) and the counter-spiral (14) radially inwardly migrating chambers are formed, wherein the counter-spiral (14) in a housing (10) with an at least partially cylindrical

Circumferential wall (11) is arranged,

d a d u rch e ke n ze i c h n et that

an outer diameter of the circumferential wall (11) is at most 10%, in particular at most 8%, in particular at most 6%, greater than an outer diameter of the counter-spiral (14).

Scroll compressor according to claim 1,

d a d u rch e ke n ze i c h n et that

the peripheral wall (11) has a wall thickness which is between 1.5 mm and 4.5 mm, in particular between 2 mm and 3.5 mm, in particular 3 mm.

Scroll compressor according to claim 1 or 2,

d a d u rch e ke n ze i c h n et that

the housing (10) has an outer diameter of at most 130 mm, in particular at most 120 mm, in particular at most 110 mm.

Scroll compressor according to one of the preceding claims,

d a d u rch e ke n ze i c h n et that

the housing (10) cup-shaped, in particular as a one-piece deep-drawn part, is formed and a bottom (12) which is integrally connected to the peripheral wall (11).

Scroll compressor according to claim 4,

I do not know that the bottom (12) has a fluid inlet (21) coaxial with

Peripheral wall (11) is aligned.

Scroll compressor according to one of the preceding claims,

d a d u rch e ke n ze i c h n et that

the housing (10) has a housing cover (20) with a fluid outlet (22), wherein the fluid outlet (22) is aligned coaxially with the circumferential wall (11).

Scroll compressor according to claim 6,

d a d u rc h e ke n ze i c h n et that

the housing cover (20) fixedly connected to the peripheral wall (11), in particular welded, is.

Scroll compressor according to one of the preceding claims,

d a d u rch e ke n ze i c h n et that

the eccentric bearing (16) is connected to a shaft (15) which is rotatably mounted in an inlet-side shaft bearing (17), wherein the inlet-side shaft bearing (17) within the housing (10), in particular on the bottom (12) is arranged.

Scroll compressor according to one of the preceding claims,

d a d u rch e ke n ze i c h n et that

the displacement spiral (13) and / or the counter-spiral (14) is / are made of plastic.

Scroll compressor according to one of the preceding claims,

d a d u rch e ke n ze i c h n et that

the housing (10) and / or the housing cover (20) is / are made of steel and / or aluminum.

11. Scroll compressor according to one of the preceding claims,

d a d u rch e ke n ze i c h n et that

the scroll compressor is dry running.

12. Scroll compressor according to one of the preceding claims,

d a d u rc h e ke n ze i c h n et that

between the turns of Verdrängerspirale (13) and the counter-spiral (14) four inwardly migrating chambers are formed.

13. An exhaust gas purification system of a gasoline engine with a scroll compressor according to one of the preceding claims.

14. The exhaust gas purification system according to claim 13,

d a d u rch e ke n ze i c h n et that

the scroll compressor is arranged in front of a soot particle filter and / or in front of a catalyst such that a secondary air flow can be introduced into an exhaust gas flow upstream of the soot particle filter and / or in front of the catalyst by means of the scroll compressor.

15. Motor vehicle with a gasoline engine and an exhaust gas purification system according to claim 13 or 14.