WO2019185351A1

WO2019185351A1 - Turbomachine, in particular a compressor device

Info

Publication number: WO2019185351A1
Application number: PCT/EP2019/056255
Authority: WO
Inventors: Thomas RACHOW; Peter Philipp; Thomas Lang
Original assignee: Robert Bosch Gmbh
Priority date: 2018-03-27
Filing date: 2019-03-13
Publication date: 2019-10-03
Also published as: CN111936748B; JP6973981B2; EP3775568B1; CN111936748A; DE102018204619A1; JP2021516311A; EP3775568A1

Abstract

The invention relates to a turbomachine (10), in particular a compressor device, comprising at least one bearing device (36; 36a; 36b) for a rotatably mounted shaft (14), wherein: the at least one bearing device (36; 36a; 36b) has at least one bearing element (40, 42; 48) for radially and/or axially bearing the shaft (14); a pressurised gaseous medium can be applied to the at least one bearing element (40, 42; 48) in order to bear the shaft (14); the shaft (14) is connected to a drivable or driven flow element (16), in particular a compressor wheel (18); the flow element (16) is arranged in a housing (20) enclosing at least part of the flow element (16); and the pressurised medium can be supplied at least indirectly from the turbomachine (10) to the at least one bearing element (40, 42; 48).

Description

description

title

Turbomachine, in particular compressor device

State of the art

The invention relates to a turbomachine, in particular a Verdichtereinrich device, with the features of the preamble of claim 1.

Such a turbomachine with a compressor device, such as is part of a turbomachine, has a shaft to be stored, wherein in the storage area, the shaft typically has a peripheral speed of more than 100 meters per second and / or a speed of more than

100,000 min ¹ may have. Since, at such high peripheral speeds or rotational speeds of the shaft, conventional rolling bearings which have oil / grease lubrication can not ensure the required service life, it is known to design the bearing device for the shaft as a compressed air-supported bearing, such that pressurized air from an external

Supply device is supplied in the form of a pressure source in a bearing bore of the bearing device. Such a pressure source for supplying the bearing device with compressed air consists for example of a separate

Compressor or a separate, from an additional device

pressurized pressure accumulator, whereby the known from the prior art compressor devices are relatively expensive or have a high device complexity.

From the post-published DE 10 2017 211 033 A1 of the Applicant, a generic turbomachine is known which does not require an additional separate supply device or compressed air source for providing the gaseous medium for the storage facility, since the compressor stage in the region of a pressure outlet, where increased by the compressor stage Pressure of the medium or the air is applied, with a supply device in the form of a Pressure accumulator is coupled, which in turn provides the air for the bearings of the storage facility or supplies them with pressurized air.

Furthermore, it is common or known in compressor devices, the

Compressor stage, in particular in the form of a compressor wheel to store rotatably in a housing. Between the housing and the compressor stage design-related gaps are formed, can flow through the pressurized medium or gas. Although it is attempted to seal these leakage gaps in particular by means of separate sealing elements, since leakage losses are synonymous with an efficiency reduction of the compressor device. However, such sealing elements require an additional

Space and increase the design effort and the manufacturing cost of the compressor device.

Disclosure of the invention

The turbomachine according to the invention, in particular Verdichtereinrich device, with the features of claim 1 has the advantage that the (gaseous) medium with little device complexity of the at least one bearing device can be fed. For this purpose, it is provided according to the invention that between the at least one flow element and the housing in a region in which the medium has an increased pressure, a leakage gap is formed, wherein the medium from the leakage gap is at least indirectly fed to the at least one bearing device, and / / or that the least one flow element has at least one pressure outlet bore for the medium via which the medium can be supplied, at least indirectly, to the at least one bearing device.

There are thus two alternative structural designs (which may optionally be used in combination) proposed, on the one hand, the use of the present in such turbomachinery leakage gap as a source for the under elevated pressure medium, or a special structural design of the flow element (compressor stage or Turbine rad) by at least one pressure outlet bore, wherein on the Druckauslass- bore the compressed in relation to an original state compressed medium of at least one bearing device can be fed.

In the event that the provision of the pressurized medium takes place from the region of the leakage gap, such a structural design of the turbomachine or compressor device has the particular advantage that the otherwise existing sealing devices are designed to be particularly simple in construction or to avoid leakage losses can even be omitted entirely, while in a solution in which at least one pressure outlet hole is provided in the region of the flow element, it is possible in a particularly simple manner, by a corresponding positioning and number or cross section of the Druckauslassbohrungen both the amount, and the Pressure of the storage of the wave required Medi order to influence or adjust in a particularly simple manner.

Advantageous developments of the turbomachine according to the invention, in particular compressor device are listed in the subclaims.

In a preferred embodiment of the turbomachine, it is provided that the leakage gap is connected via at least one pressure line for the medium immedi applicable to the at least one bearing device. What is meant by this is that the connection between the leakage gap and the bearing device takes place exclusively via a corresponding (pressure) line and, in contrast to the aforementioned prior art, for example, no pressure accumulator designed as a separate component is required.

In a similar manner, it is provided in the provision of at least one pressure outlet hole in a preferred embodiment that the at least one pressure outlet bore is connected via at least one pressure line for the medium immedi applicable to the at least one bearing device.

In particular, in the event that the pressure or the amount of the provided by the Strö determination machine or compressor device medium for we least one storage device varies, it may alternatively be provided that in the flow path of the at least one pressure line as a separate component trained pressure accumulator is arranged. The pressure accumulator ensures that at times small amounts or low pressures of the medium sufficient (gaseous) medium is ready for storage of the shaft.

In particular, in the latter solution with a separate accumulator, but also for the case in which the medium via the pressure line directly from the region of the leakage gap or the at least one Druckauslassboh tion of the bearing device can be supplied, it can be provided that the we least one storage device a pressure regulating device is connected upstream, which regulates the pressure or the amount of medium which can be supplied to the bearing device. In this way, in particular, the bearing of the shaft is negatively influenced, excessive pressures of the medium are avoided.

To reduce the constructive effort or the size of the Strö tion machine, in particular compressor device, it may be provided in particular in a variant in which the medium from the region of the leakage gap is Won, that the area of the leakage gap is formed dichtungsele mentfree.

In a constructive variant of the turbomachine, in particular compaction tereinrichtung, whose flow element has a radial design ausgebil detes compressor wheel, wherein the at least one pressure outlet hole is arranged on egg nem pitch circle diameter about the rotational axis of the shaft and cooperates with a arranged in a separate component annular groove, whose at least one passage bore facing away from the at least one bearing device is connected. Such a configuration has the part before that upon rotation of the compressor wheel, the pressure outlet hole at least temporarily in operative connection with the annular groove and thus the bearing device is arranged.

In a particularly preferred embodiment of the last proposal made, it is provided that the separate component ring-shaped or disc-shaped and is arranged stationarily in relation to the flow element that the least one pressure outlet hole is formed as a through hole extending between two opposite axial end faces of the flow element extends, and that the annular groove is designed as a radially encircling the axis of rotation, circular-shaped annular groove. Such a configuration in particular special of the annular groove has the advantage that during the entire rotation of the flow element about its axis of rotation always a pneumatic connection between the at least one pressure outlet bore and the bearing means via the annular groove can be formed.

A further structural design which reduces the expense of the bearing device, provides that the bearing device is a thrust bearing which acts on opposite end faces of a bearing disc connected to the shaft, and that the medium acts only on the end face of the bearing disc facing the flow element. Such an embodiment provides that on the end face of the bearing disc facing away from the flow element, the bearing device is either supplied via a different medium source, or else via a bearing element of a different construction, e.g. a foil bearing, a storage via spiral grooves or the like has.

Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments and from the drawing.

This shows in:

Fig. La

and

Each lb a simplified longitudinal section in the region of a Verdichterein direction, is provided in the gaseous medium for supplying a ger ger or radial bearing designed as Axialla or radial bearing from the range of a leakage gap,

2 shows a longitudinal section through a modified compressor device, is provided in the medium for a storage facility in the range of Druckauslassboh ments on a compressor wheel, Fig. 3 shows a detail of a comparison with FIGS. 1 and 2 modified compressor device using an intermediate Druckspei Chers and

Fig. 4 is a comparison with FIGS. 1 and 2 modified compressor device, wherein the bearing device is supplied only at one end face with medium from the compressor device.

The same elements or elements or the same function are provided in the figures with the same reference numerals.

The turbomachine shown greatly simplified in FIGS. 1a and 1b is, for example, part of a fuel cell system, an air conditioning system, a heat pump, a turbocharger, a turbine for a fuel cell system or a heat recovery turbine. In the illustrations of Fig. La and lb, the turbomachine in the form of a compressor device 10 is ausgebil det.

The compressor device 10 comprises a shaft 14 which is mounted in a rotation axis 12 and to which an end face of a compressor stage 16 in the form of a compressor wheel 18 of radial design is connected in a rotationally fixed manner to the shaft 14. The compressor stage 16 or the compressor wheel 18 is surrounded by a housing 20 having an inlet region 22, is sucked through the gaseous medium, in particular air, in the compressor device 10, and upon rotation of the shaft 14 about the axis of rotation 12 through the compressor stage 16 is compressed or increased in pressure so that it exits in the region of an outlet region 24 of the housing 20 under increased pressure and can be supplied to a consumer, not shown.

Between a radially surrounding the axis of rotation 12 peripheral edge region 26 of the compressor 18 and a receiving opening 28 for the compressor 18 in the housing 20, a radially encircling leakage gap 30 is formed, via which the pressure in its increased pressure relative to the inlet portion 22 increased medium can escape. By way of example, the region of the leakage gap 30 on the side facing away from the Ge 20 of an annular, to the leakage gap 30 back open collecting element 32 is surrounded, via which the leaking from the leakage gap 30 medium via at least one pressure line 34 directly to a La gereinrichtung 36 for the shaft 14 can be fed.

The bearing device 36 is formed in FIG. La as a thrust bearing and has two opposite end faces of a non-rotatably connected to the shaft 14 nen NEN bearing plate 38 arranged, annular bearing elements 40, 42. The two bearing elements 40, 42 each have feed holes 44, 46, via which the pressurized medium from the pressure line 34 acts on the end faces of the bearing ring 38 and provides a corresponding pressure pad to an axial bearing of the shaft 14 to the housing 20th to enable.

In Fig. Lb, the bearing means 36a in contrast forms out as a radial bearing and comprises a shaft 14 radially enclosing bearing element 48, the supply via feed bores 50, 52 and the at least one pressure line 34 immediacy bar with pressurized medium from the leakage gap 30 can be supplied ,

In Fig. 2, a modified compressor device 10 is shown, in which a compressor 55 at least one, but preferably a plurality of evenly spaced on a pitch circle diameter about the axis of rotation 12 arranged Druckauslassbohrungen 56 in the form of through holes 58 which are parallel to the shaft 14 extend. The Druckauslassbohrun conditions 56 connect the housing 20 facing the end face of the compressor wheel 55, which is present at the medium under pressure, with the rear end face 60 of the compressor 55th

While the number and diameter of the pressure outlet bores 56 determines the amount of fluid available to the bearing means 36a, the radial distance of the pressure outlet bores 56 from the axis of rotation 12 determines the level of pressure of the medium for the bearing means 36a.

The compressor 55 is positioned on the side facing away from the housing 20 at least in the region of the pressure outlet bores 56 in register with a ringförmi gene, stationarily arranged element 62. The element 62 has a radial on the same pitch circle diameter as the pressure outlet bores 56 circumferential annular groove 64, which in turn is arranged via at least one pressure line 66 with the bearing means 36a in operative connection.

In Fig. 3 the case is shown, in which the at least one pressure line 34, 66 with the interposition of a pressure accumulator 70 and a Druckregelein device 72 with the bearing means 36, 36 a is connected.

Finally, FIG. 4 shows the case in which the bearing ring 38 of the bearing device 36 b has a bearing element 40 on one of the compressor stages 16, which is supplied with pressurized medium by the compressor device 10, while the other Front side of the bearing ring 38 with the bearing element 76 either via a different (pressure) source 74 in the direction of the housing 20 is subjected to force. Alternatively, the Lagerele element 76 may also be a bearing element 76, which is not designed as gasdruckbeaufschlagtes bearing element 76.

The compressor device 10 described so far can be modified or modified in many ways, without dodging from the idea of the invention. For example, the compressor stage 16 may have a compressor wheel designed in an axial construction. Also, the principle of action can also on one

Turbine or working machine are applied. In this case, instead of the compressor stage 16 or the compressor wheel 18, a work stage or a turbine wheel is used accordingly.

Claims

claims

1. Turbomachine (10), in particular compressor device with

at least one bearing device (36; 36a; 36b) for a rotatably arranged shaft (14), wherein the at least one bearing device (36; 36a; 36b) comprises at least one bearing element (40,42; 48) for the radial and / or axial mounting of the shaft (14), wherein the at least one bearing element (40, 42; 48) is pressurized with pressurized gaseous medium for supporting the shaft (14), wherein the shaft (14) with a drivable or driven flow element (16), in particular a compressor wheel (18) is connected, wherein the

Flow element (16) in a flow element (16) at least partially surrounding housing (20) is arranged, and wherein the pressurized medium at least indirectly from the turbomachine (10) the at least one bearing element (40, 42, 48) can be fed, characterized in that between the at least one flow element (16) and the housing (20) a leakage gap (30) is formed, wherein the medium from the leakage gap (30) at least indirectly at least one

Storage device (36, 36a) can be fed, and / or that the

Flow element (16) has at least one pressure outlet bore (56) for the medium, via which the medium at least indirectly to the at least one bearing means (36; 36a, 36b) can be fed.

2. Turbomachine according to claim 1,

characterized,

in that the leakage gap (30) is connected to the at least one bearing device (36; 36a; 36b) via at least one pressure line (34) for the medium.

3. Turbomachine according to claim 1 or 2,

characterized,

in that the at least one pressure outlet bore (56) is connected at least indirectly via at least one pressure line (66) for the medium to the at least one bearing device (36; 36a; 36b).

4. Turbomachine according to claim 2 or 3,

characterized,

that in the flow path of the at least one pressure line (34; 66) designed as a separate component pressure accumulator (70) is arranged for the medium is.

5. Turbomachine according to one of claims 2 to 4,

characterized,

in that the at least one bearing device (36; 36a; 36b) is preceded by a pressure-regulating device (72) which regulates the pressure of the medium.

6. Turbomachine according to one of claims 2 to 5,

characterized,

the region of the leakage gap (30) is designed to be free of sealing elements.

7. Turbomachine according to one of claims 2 to 6,

characterized,

in that the flow element (16) is designed as a compressor wheel (18) designed in a radial design such that the at least one pressure outlet bore (56) is arranged on a pitch circle diameter about the axis of rotation (12) of the shaft (14) and with one in a separate one Component (62) of ordered annular groove (64) cooperates, the at least one passage bore (56) facing away from the at least one bearing device (36, 36 a) is connected.

8. Turbomachine according to claim 7,

characterized, in that the component (62) is of annular design and is arranged stationarily in relation to the flow element (16), that the at least one pressure outlet bore (56) is designed as a through-bore (58) which extends between two opposite axial end faces of the flow element (16 ), and in that the annular groove (64) is designed as a circular annular groove (64) running radially around the axis of rotation (12).

Turbomachine according to one of claims 1 to 8,

characterized,

in that the bearing device (36b) is a thrust bearing which acts on opposite end faces of a bearing disc (38) connected to the shaft (14), and that the medium acts only on the end face of the bearing disc (38) facing the flow element (16) , 10. Turbomachine according to one of claims 1 to 9,

characterized,

the turbomachine is designed as a compressor device (10).