WO2020064799A1

WO2020064799A1 - Film gas bearing device for mounting a rotor and method and use

Info

Publication number: WO2020064799A1
Application number: PCT/EP2019/075806
Authority: WO
Inventors: Jürg SCHIFFMANN; Eliot Guenat; Karim Shalash
Original assignee: Ebm-Papst Mulfingen Gmbh & Co. Kg
Priority date: 2018-09-26
Filing date: 2019-09-25
Publication date: 2020-04-02
Also published as: DE202018105842U1; DE102018216520A1; CN210050203U

Abstract

In the case of film gas bearings for rotors, there is an interest in high load-bearing capability and robust mounting, in particular even at high rotational speeds. Stability and positional tolerance in the radial direction are further important requirements. A film gas bearing device (10) is provided for mounting a rotor (12) by means of gas (G), with a rotor-side top film device (14) and with a bump film device (15) which supports the top film device in a bearing bush, wherein the film gas bearing device comprises a plurality of recesses (17) which run obliquely with respect to the axial direction (x) and obliquely with respect to the circumferential direction (α), are arranged in at least one axial section (17.3, 17.4, 17.5) of the bearing system, and are set up to build up a pressure in a radial gap (13) of the bearing system, which radial gap (13) is formed between the rotor and the top film device, in particular even in an unstructured axial section (17.6). As a result, a robust and tolerant bearing with a high load-bearing capability in the radial direction and also for high rotational speeds can be provided. Furthermore, the invention relates to a method and to a use for a film gas bearing device of this type.

Description

Foil gas storage device for storing a rotor and method and

use

TECHNICAL AREA

The present invention relates to a device for supporting a rotor or a shaft by means of gas, e.g. for air storage, especially for oil-free storage. In particular, the invention relates to a device for supporting a rotor in the radial direction and / or at high rotational speeds. Last but not least, the present invention also relates to the use of radial foil gas bearings.

In particular, the invention relates to a device and a method according to the preamble of the respective independent claim.

BACKGROUND OF THE INVENTION

So-called foil gas bearings or foil bearings have proven to be useful for mounting a rotor or a shaft, in particular in the radial direction and / or at high rotational speeds. Foil gas bearings are used, for example, in pumps at high speeds of rotation of the respective rotor. Comparatively small friction losses and / or comparatively long lifetimes can be achieved by means of foil gas bearings. In particular in the case of storage in the radial direction, position tolerances can also be compensated for. In particular, load gas fluctuations in the radial direction (transverse to the axis of rotation of the rotor) can be absorbed by means of foil gas bearings, so that

Foil gas bearings can also have a damping function.

Conventional foil gas bearings consist of foil layers with largely flat, flat surfaces. A surface which is arranged in particular statically relative to the rotor (top foil or so-called top foil) delimits an air gap and is elastically deformable and yields to a pressure generated in the air gap in particular as a function of a rotational speed. The top film is caused by the pressure conditions and by movements of the rotor in the radial direction

deformed. As a result, the rotor or the shaft can be mounted in a position-tolerant manner in the radial direction. In particular, a pressure field leads within a bearing gap between the rotor and the adjacent top foil to a deformation of the top foil. The type of cushioning provided by the top film also defines the properties of the entire bearing. The top film is stored on a further film (bump film) on a carrier

(for example bearing bush) is supported. The properties of the foil gas bearing, in particular the load-bearing capacity in the radial direction, are therefore strongly predefined by the configuration of the foils (top foil and bump foil) and by the rotor interacting with the foils. When designing and optimizing foil gas bearings, there is therefore interest in being able to influence and optimize the effects of the foils on the rotor and on the formation of the pressure ratios as precisely as possible, especially in the radial direction.

The patent specification EP 2 375 089 B1 describes a dynamic foil gas storage with web-like foils with holding surfaces and connecting surfaces.

Based on this prior art, there is interest in improving the technical possibilities and features of film bearings, particularly with regard to the requirements for radial bearings.

SUMMARY OF THE INVENTION

The object is to provide a device for gas storage or air storage of a rotor (or a shaft), with which the rotor can be supported with a high load-bearing capacity, in particular in the radial direction and / or in particular at high rotational speeds. In particular, the object is to enable efficient, oil-free mounting of a high-speed rotor, at least in the radial direction, in such a way that a comparatively high radial force can be applied to the rotor and it can also be supported in a position-tolerant manner, in particular also with advantageous side effects with regard to friction

Development of heat and stability.

This object is achieved by a film gas storage device according to claim 1 and by a method according to the respective subordinate method claim. Advantageous developments of the invention are given in the respective

Sub-claims explained. The characteristics of those described below Exemplary embodiments can be combined with one another, unless this is explicitly denied.

A foil gas bearing device is provided for storing a rotor by means of gas, with a rotor-side top foil device for radial

Bearing of the rotor in a bearing bush, and with a bump film device supporting the top film device in the bearing bush in the radial direction on a carrier. The bump film device is preferably set up for a damping deformation of the top film device, in response to a pressure exerted on the bearing level or by the rotor.

It is proposed according to the invention that the foil gas bearing device comprises a plurality of recesses which run obliquely to the axial direction x and obliquely to the circumferential direction a, which are arranged in at least one axial section of the bearing and are designed to build up a pressure in a between the rotor and the top Film device formed radial gap of the storage, in particular also in an unstructured axial section. This provides a robust, position-tolerant, stable bearing, even at high speeds, even at high loads.

It has been shown that the recesses in particular in the

arrangement according to the invention can increase the pressure in the warehouse. As a result, the rotor lifts even at a comparatively low speed and becomes contactless with the top film even at a low speed, so that friction can also be reduced, particularly in start-stop applications. This also has a positive effect on the life of the bearing. The arrangement according to the invention provides advantages in particular also in the starting behavior of radial foil bearings.

In contrast to previously tried-and-tested technologies, in particular in contrast to the film bearings described above, the field of application of the film gas bearings can also be expanded with simple means according to the invention with high system security. A high radial load-bearing capacity can also be achieved. Furthermore, the friction loss of the bearing can be minimized. In particular, a combination of the technical features “recesses” and “unstructured axial section, in particular a centrally arranged axial section” enables an improvement the bearing properties. In particular, a radial foil bearing with recesses in the form of spiral grooves can be provided for this.

A conventional radial foil gas storage usually has two foil parts: the so-called top foil (top foil), and the so-called bump foil (bump foil), the top foil resting on the flexible, damping bump foil, and where the top foil together with the rotor limits or delimits the gas film in the radial direction on both sides. The flexible bump foil can be an (elastic)

Enable deformation of the top foil and predefine the type of damping, especially when pressurized or under pressure (pressure field of the gas film) at high rotational speeds. This also enables a comparatively large positional tolerance (relatively high deflection of the shaft without risking mechanical contact). This also has advantages in terms of alignment errors, manufacturing tolerances or thermal effects (thermal expansion).

A technical difficulty is caused by the fact that foil bearings react comparatively sensitively to aerodynamic instabilities. A

Experience has shown that the damping effect that can be produced in connection with frictional forces between the top foil and the rotor does not in itself provide a sufficiently effective measure to get a better grip on this aerodynamic instability. There is therefore a further need for optimization.

Proceeding from this, the invention is based on the concept of producing high stability and good damping and load-bearing properties by providing recesses on the top of the top film device and / or on the rotor, in particular recesses in the form of grooves, which recesses are set up to pump gas axially inwards with a relative rotary movement between the rotor and the top film device.

The recesses can already act alone in a static arrangement (as static grooves), that is to say based solely on a rotation of the rotor relative to the top film device. However, the recesses can also be dynamic

Arrangement act, so when they are rotated together with the rotor. The Recesses are set up to convey gas into the air gap of the bearing (in particular in the sense of: pumping gas), in particular with the effect of increasing the pressure of the gas film in the air gap, in particular on at least one

predefinable axial position.

The recesses or grooves are advantageously arranged in a spiral, at least in sections. The recesses can be designed or arranged as inward (axially inward) pumping grooves. The recesses can in particular begin exactly on the outside of the respective outer edge. The recesses can, in particular, run or be arranged axially inward up to a more centric axial position. For example, the recesses extend to just before half the total axial extent of the bearing surface (almost half the axial length of the bearing or the bearing gap).

The recesses, in particular grooves, are advantageously arranged in an axially outer angle (on an axial outer edge) of 110 to 175 °, in particular greater than 115 ° or greater than 120 ° or greater than 125 ° with respect to the circumferential direction. The recesses, in particular grooves, are advantageously arranged in an axially inner angle (in particular at an axial position adjacent to an unstructured axial section) of 115 to 155 °, in particular greater than 120 ° or greater than 130 ° or greater than 135 ° in relation to the circumferential direction. This delivers high efficiency, in particular an optimal pumping effect.

Here, an outer angle ß on one / the axial outer edge of the

Recesses relative to the circumferential direction may be smaller than an inner angle g at an inner axial position or an inner end of the recesses, in particular with respect to the axial direction. This enables, in particular, expedient alignment of a gas film (specification of a flow path) in the circumferential direction, in particular in an unstructured axial section.

The recesses, in particular grooves, can be arranged or introduced in an orientation from the inside to the outside, at least partially and / or in sections in the circumferential direction and / or in sections in the axial direction. The recesses, in particular grooves, can be arranged in opposite directions or be introduced, at least partially and / or in sections in the circumferential direction and / or in the radial direction in sections.

Thanks to the configuration according to the invention, the geometry of the recesses on the top film device or on the rotor, for example, can also be easily optimized and adapted to the respective application or the desired pressure conditions or relative speeds or gas densities, in particular to maximize the load-bearing capacity and / or Increase in efficiency (reduction of loss of effectiveness). For example, a

A large number of axial sections can be provided, in particular if the air gap has a comparatively large axial extent. In this way, the heat balance can also be optimized. In other words, the removal of thermal energy in particular can be ensured in a simpler way. Furthermore, the

Recesses according to the invention can be produced in a comparatively straightforward manner, in particular in a simple, inexpensive manner

Manufacturing step.

The recesses according to the invention, in particular in the form of

Spiral grooves, in an arrangement on a statically arranged, flexibly mounted surface of a gas bearing and / or in a dynamically rotating arrangement on the surface of the rotor (in particular integrally in the material of the rotor

provided), deliver in particular in combination with at least one

unstructured axial section a noticeable improvement in load-bearing capacity and running properties. In contrast to the present invention, an arrangement deviating therefrom has hitherto been used in the prior art, namely an essentially flat upper side of the top film was provided, or a structuring of any surfaces could not be sufficient

ensure satisfactory improvements in the bearing characteristics.

The foil gas storage device can be specifically designed to accommodate im

Be set up essentially radially aligned forces. In this case, the film gas storage device can also be referred to as a film gas radial storage device. According to one exemplary embodiment, the top film device is structured on its upper side by the recesses, in that the recesses are incorporated into a top film of the top film device, corresponding to a static one

Arrangement of the recesses. This also makes it possible to ensure the advantages according to the invention regardless of the configuration of the rotor.

According to one exemplary embodiment, the rotor is structured on the upper side thereof by the recesses, in that the recesses are worked into the surface of the rotor, in accordance with a dynamic, rotating arrangement of the recesses. This also makes it possible to ensure the advantages according to the invention by means of the rotor or to additionally support the effect.

According to one embodiment, the recesses define one

Flow path inward axially, which predefined flow path ends at an unstructured axial section, in which a gas film can form without a predetermined structure. On the one hand, this enables a targeted influence on a pumping action, on the other hand, there remains the possibility that a carpet of carpets can develop freely depending on the operating state of the bearing, in particular even with minimized friction. This can also have an advantageous effect on the load-bearing capacity.

According to one exemplary embodiment, when the rotor rotates, the recesses are designed to convey gas in at least one axial direction, in particular in both opposite axial directions. The delivery in opposite directions, in particular towards at least one unstructured axial section, provides a good effect. The measures according to the invention can be implemented particularly efficiently.

Advantageous (in particular geometric) configurations of the recesses are described in more detail below.

According to one embodiment, the recesses run from axially outside to axially inside to an unstructured axial section of the

Foil gas storage device and end there. According to one embodiment, the recesses run on both sides from axially outside to axially inside to an unstructured axial section of the

Foil gas storage device and end there at an axial distance from one another. This arrangement has proven to be particularly effective. According to one exemplary embodiment, the recesses are designed to build up a pressure in / in the unstructured axial section of the film gas bearing device. The recesses can preferably be provided in full.

According to one embodiment, the recesses are in two axial

Sections arranged and aligned in opposite directions, in particular each with a spiral course, in particular at least approximately the same amount relative to the axial direction. It has been shown that the opposing alignment of the recesses, even with a top film, can provide an advantageous effect in terms of viscous pumping action for increasing the pressure in the gap between the top film and the rotor. This also has a positive effect on the stability of the bearing in the radial direction.

According to one embodiment, the recesses are in two axial

Sections arranged and open into a in each of the sections

intermediate unstructured axial section. According to one

Embodiments are the recesses in two axial sections

arranged, which are axially at least approximately the same length, and the recesses open into / in the unstructured axial section arranged in between, which is axially at least approximately as long as a single structured

Section. This also provides advantageous aerodynamic properties or can promote smooth running and high load-bearing capacity.

According to one exemplary embodiment, the recesses form two structured axial sections which have an unstructured one arranged between them

Limit the axial section, wherein the two axial sections and the unstructured axial section arranged between them are provided over the entire axial length of the rotor and / or the top film device or can also protrude beyond it. This can provide a particularly effective, stable bearing even with little axial installation space. In the case of a single radial bearing point, the axial sections can also protrude beyond the top film device. With very short rotors, especially with a small ratio of axial length to diameter, a radial bearing point can be sufficient. In the case of rotors, the total axial length of which is significantly greater than their diameter, the axial extent of the radial bearing is smaller than the total length, usually two or more radial bearing points being provided.

According to one embodiment, the recesses extend from an outer edge of the top film device and / or of the rotor and extend axially inwards. This also favors a pumping action.

According to one exemplary embodiment, the recesses are designed to convey (or pump) gas axially inward when the rotor rotates. This also favors the generation of a comparatively high gas pressure or

Gas flow.

According to one embodiment, the recesses are designed as grooves or as grooves. As a result, the recesses can also be produced in a comparatively simple manner. Grooves or grooves can also be individually designed in terms of geometry, shape and depth.

According to one embodiment, the recesses have a constant depth, at least over a length section greater than half the length of the

Recesses, in particular up to an axially inner end of the

Recesses or until shortly before. This also enables largely constant flow conditions within the respective recess.

According to one embodiment, the recesses have a continuous run-out area with a continuously decreasing depth at / at the respective inner end. In particular, this favors a transfer of gas flows out of the recesses into a gap between two flat surfaces. This can favor the formation of a stable gas film. Advantageous orientations of the recesses are described in more detail below.

According to one embodiment, the recesses run at least in sections in the axial direction. This enables efficient inward pumping.

According to one embodiment, the recesses are curved at least in sections. According to one embodiment, the

Recesses at least in sections spiral. This also provides advantages in terms of friction, conservation of momentum and the most homogeneous possible pressure conditions.

According to one exemplary embodiment, the respective recess runs at least in sections in a straight line without curvature (radius of curvature zero), in particular axially on the outside. This also favors the feeding of gas, especially into

Dependency of a speed or a configuration of the rotor or one

Distance between the top foil device and the rotor.

According to one exemplary embodiment, an outer angle on an axial outer edge of the recesses is greater than 125 ° or greater than 130 °, in particular with respect to the circumferential direction. According to one embodiment, an inner angle at an inner edge or at an axially inner end is

Recesses greater than 130 ° or greater than 135 °, especially in relation to the circumferential direction. This also provides a good effect in terms of stability and load-bearing capacity and smoothness.

Advantageous arrangements of the recesses are described in more detail below.

According to one embodiment, the recesses extend from one / the outer edge of the top film device or the rotor at least to 1/3 of the available axial bearing surface. This also enables one To generate a stabilizing effect based on fluid dynamics phenomena, especially due to varying cross-sectional profiles in individual axial sections. The axial length of the recesses can also in

Depending on the design of the rotor can be selected.

According to one exemplary embodiment, the recesses extend from a respective outer edge at least to 1/3 of the axial length of the top foil device or of the rotor. This also enables an effective pumping in of gas in connection with the formation of a gas film axially further inside. Depending on the desired interaction between the top foil device and the rotor, a more or less wide gas film (in particular without interaction with recesses) may be desired. For this purpose, an unstructured axial section in size and

Position can be adapted to the respective application.

According to one exemplary embodiment, the recesses extend from an outer edge of the top film device or of the rotor to a maximum of 2/5 of the axial length of the top film device or of the rotor. This leaves space axially on the inside for the formation of a gas film independently of recesses, in particular if the gas film is to be as little turbulent as possible or should be disturbed as little as possible by recesses.

According to one embodiment, the recesses of an axial section all extend from an axial outer edge to the same

Axial position to an unstructured axial section. This can make it possible to exert a very targeted influence on the gas transport inward axially, and it is also possible to exert an influence on the gas distribution, in particular depending on the design or size of an unstructured axial section arranged axially more centrally. Last but not least, friction can be minimized.

According to one embodiment, the foil gas bearing device is set up for oil-free radial bearing of the rotor exclusively by means of gas, in particular by means of air. As a result, the storage can be further simplified or optimized. Furthermore, a wide range of applications can be opened up. According to one embodiment, the top film device is flexible. The top film device can be provided from a flexible material. The storage properties can then also be determined by the material properties and / or by the manner in which the bump film device is arranged. In this way, a damping function can also be fulfilled by means of the top film device, in particular depending on the manner in which the top film device is supported by the bump film device.

According to one embodiment, the recesses in the top film device are arranged statically or can be arranged statically relative to the rotor. The relative rotary movement is then determined exclusively by the manner in which the rotor rotates. Last but not least, this also makes it possible to provide a simple, robust, low-maintenance bearing arrangement.

The aforementioned task is also solved in particular by a

Foil gas storage device set up for storing a rotor by means of gas, with a rotor-side top foil device for radial mounting of the rotor in a bearing sleeve, and with a bump foil device supporting the top foil device in the bearing sleeve in the radial direction on a carrier, the

Foil gas storage device comprises a plurality of obliquely extending to the axial direction x and obliquely to the circumferential direction a, which in

at least one axial section of the bearing are arranged and set up to build up a pressure in a radial gap of the bearing formed between the rotor and the top film device and also in an unstructured axial section, the top film device being structured on the upper side by the recesses or the rotor is structured on its upper side by the recesses, the recesses being one

Define the flow path axially inward, which predefined flow path ends at the unstructured axial section, the recesses running on both sides from axially outside to axially inward to the unstructured axial section and ending there at an axial distance from one another, the recesses being provided in full, the recesses being grooves or are designed as grooves, the recesses being arranged in at least two axial sections are and are oriented in opposite directions, the recesses running at least in sections spirally, and the foil gas bearing device being designed for oil-free radial bearing of the rotor exclusively by means of gas, in particular by means of air or also by means of gaseous refrigerant. This results in numerous advantages mentioned above.

The aforementioned task is also solved by using a

Foil gas storage device, in particular one previously described

Foil gas storage device, for radial storage of a rotor oil-free exclusively by means of gas, a top film device of the film gas storage device being arranged relative to the rotor and relative to the direction of rotation of the rotor such that or is arranged on the top of the top film device and / or on the top of the rotor recesses made therein extend obliquely to the axial direction x and obliquely to the circumferential direction a and are arranged in at least one axial section of the bearing and are set up to build up a pressure in a radial gap of the bearing formed between the rotor and the top film device and in particular also in an unstructured axial section, in particular use of the foil gas storage device in a heat pump or in a device with a heat pump. This results in the aforementioned advantages.

The above-mentioned object is also achieved by a foil gas storage device, in particular a previously described foil gas storage device, produced by structuring the top foil device and / or the rotor on the respective top side by a plurality of recesses running obliquely to the axial direction x and obliquely to the circumferential direction a, which are arranged in at least one axial section of the bearing such that the

Foil gas bearing device is set up to build up a pressure in a radial gap of the bearing formed between the rotor and the top foil device and in particular also in an unstructured axial section. This results in the aforementioned advantages. The aforementioned object is also achieved by a method for providing a foil gas storage device, in particular one described above

Foil gas storage device for storing a rotor by means of gas, comprising the steps of: providing a bump foil device which can be supported on a carrier in a bearing bush for supporting a top foil device in the radial direction; Arranging and fastening the top film device on the bump film device for radial mounting of the rotor; wherein the top foil device is arranged in such a way that a plurality of recesses of the foil gas bearing device, which run obliquely to the axial direction x and obliquely to the circumferential direction a, which are provided on the top of the top foil device and / or on the rotor, in at least one axial section of the bearing are arranged and set up to build up a pressure in a radial gap of the bearing formed between the rotor and the top film device, in particular also in an unstructured axial section. This results in the aforementioned advantages.

According to one embodiment, the method also includes structuring the top of the top film device (or the top film) and / or the rotor by introducing the recesses. This allows the properties of the

Foil gas storage device can be adapted even more specifically to an application. In particular, a radial foil gas bearing device with recesses in the form of spiral grooves can be provided, in particular spiral grooves arranged in opposite directions on both sides.

BRIEF DESCRIPTION OF THE FIGURES

The invention is described in more detail in the following drawing figures, reference being made to the other drawing figures for reference signs which are not explicitly described in a respective drawing figure. 1 and 2 each show a perspective view of a rotor (shaft) arranged axially in alignment in a perspective view to the side and from the front for arrangement and radial mounting in a bearing bush

Foil gas storage device according to one of two exemplary embodiments.

DETAILED DESCRIPTION OF THE FIGURES 1 shows a film gas bearing device 10 in which a rotor 12 (here: shaft) is mounted in the radial direction r. A gap or air gap 13 is formed between the rotor 12 and a top foil device 14, which gap is filled with gas G, in particular ambient gas or ambient air. The top film device 14 is supported on a bump film device 15 (so-called bump foil; or compliant foil) and can thereby also be damped in a certain sense, and the bump film device 15 is supported on a carrier 16 in a bearing bush 1.

The rotor 12 rotates relative to the top film device 14. The direction of rotation a of the rotor or, correspondingly, the circumferential direction or a corresponding angle of rotation is indicated by the dashed line arrow. The axial direction is indicated by the arrow x (viewed counterclockwise in the x direction), and the radial direction is indicated by the arrow r.

Pressure conditions occur in the air gap 13, depending on the ambient pressure, relative rotational speed and bearing load. By means of the

Arrangement can be influenced on these pressure conditions, as explained in more detail below.

1 shows a first exemplary embodiment. Recesses 17 are provided on the top 12a of the rotor 12, in particular in the form of grooves, the recesses 17 being machined into the material of the rotor. The recesses 17 are arranged in two axial sections 17.4 and 17.5 and run in opposite directions in such a way that the inner ends 17.1 of the recesses open into an unstructured axial section 17.6, in particular for pumping gas / air into this unstructured axial section 17.6, ie for setting the pressure conditions in particular also in an area centrally axially centric with respect to the entire axial bearing section 17.3, which is the radial

Storage of the rotor is provided. The length ratios of the individual axial sections are indicated by the reference numerals x1, x2, x3 and x4, where xO in each case marks an axial outer edge (starting point) of the respective recess. This axial outer edge can also be the outer edge 12.3, 14.3 of the rotor or the top film device. For example, x1 and x4 are at least approximately the same size. For example, the unstructured section 17.6 is at least approximately as large as x1 and / or as x4. Especially with only one bearing point, x3 (absolute axial

Extent of the recesses) must be at least approximately as large as the absolute length of the rotor. For example, the outer end edges (axial outer edges) xO of the recesses coincide with the axial start or end of the rotor. In this case, x3 can also be greater than the axial extent of the top film device. With elongated rotors and several bearings, x3 is significantly smaller than the absolute rotor length.

It has been shown that the total axial length of the respective structured radial bearing can usually be selected to be somewhat larger than the absolute length of the top foil device, in particular if the recesses (grooves) are arranged on the rotor. The structured areas then protrude beyond the ends on the left and right of the fixed bushing.

In Fig. 1, an outer angle β or inner angle g of the recesses is also indicated with respect to the circumferential direction. According to a variant, the angles are at least approximately the same size (for example in the range of 135 °). According to another variant, the inner angle is larger, i.e. the recess extends further inward at an acute angle to the circumferential direction.

A further exemplary embodiment is described in FIG. 2. The recesses 17 are integrated in the top film device 14, namely in a top film 14.2 on the top 14a.

The radially outward-facing underside 14b can remain unstructured.

The top foil device 14 defines with its top 14a the position of the radial bearing (in the sense of a bearing plane or cylindrical

Bearing surface).

In both exemplary embodiments (FIGS. 1 and 2), an advantageous bearing characteristic can be set by moving from the outside axially to the inside on both sides a pump effect is generated, with the effect of a pressure build-up, in particular in the at least approximately axially centrally arranged unstructured axial section 17.6. On the one hand, this provides high stability, on the other hand, a very good-natured, (position) tolerant bearing characteristic.

The top foil device 14 and / or the rotor thus has a multiplicity of individual recesses 17, in particular in each case in the form of grooves, the recesses extending over at least one axial section 17.4, 17.5 which, depending on the requirements, can be significantly smaller than the absolute axial length of the rotor or the bearing section 17.3.

The following colloquial term is conceivable for such a structured top film 14.2 or for the structured top film device 14:

Grooved top foil.

In the variants shown, the recesses run at least in sections in a spiral and are provided over their entire circumference, be it on / in the rotor or in the surface of the top film device. The recesses 17 can be used to pump gas or air axially inwards, namely along a flow path defined by the recesses (indicated by a dotted line in FIG. 1), in particular to adjust the characteristics of a gas film formed between the rotor 12 and the top film device 14 to be able to, in particular for regulating the flow and pressure conditions with relative rotation of the rotor relative to a statically arranged top

Foil setup. Reference list

1 bearing bush

10 foil gas storage device

12 rotor

12a top

12.3 Outside edge

13 gap, in particular air gap

14 Grooved Top Foil

14a upper side (radially inner side)

14b underside (radially outer side)

14.2 Top film

14.3 Outside edge

15 bump film setup

16 carriers

17 individual recess, in particular groove

17.1 inner (axial) end of a recess in the axial direction

17.3 axial bearing section (with or without recesses)

17.4 first axial section, structured with recesses

17.5 second axial section, structured with recesses

17.6 unstructured axial section

G gas, in particular ambient gas or gaseous refrigerant

xO outer end edge (axial outer edge) of recesses

x1, x2, x4 axial length of the recesses or inner axial position of a

inner end of the recesses

x3 absolute axial extent of the recesses (axial bearing section) a direction of rotation of the rotor, or circumferential direction or angle of rotation

ß outer angle of the recesses, particularly with respect to the

Circumferential direction

g inner angle of the recesses, in particular with respect to the

Circumferential direction

x axial direction or axis of rotation of the rotor or shaft

r radial direction

Claims

1. foil gas storage device (10) set up for storing a rotor (12) by means of gas (G), with a rotor-side top foil device (14) for radial mounting of the rotor in a bearing bush (1), and with a the top foil device in the Bearing sleeve (15) supporting a bearing bush in the radial direction on a support (16),

characterized in that the film gas bearing device (10) comprises a plurality of recesses (17) which run obliquely to the axial direction (x) and obliquely to the circumferential direction (a) and which are arranged in at least one axial section (17.3, 17.4, 17.5) of the bearing and are set up to build up a pressure in a radial gap (13) of the bearing formed between the rotor and the top film device, in particular also in an unstructured axial section (17.6).

2. Foil gas storage device according to claim 1, wherein the top foil device (14) on its upper side (14a) is structured by the recesses (17) by the recesses (17) in a top foil (14.2) of the top foil device (14 ) are incorporated; and / or wherein the rotor on its upper side (12a) is structured by the recesses (17) in that the recesses are worked into the surface of the rotor (12).

3. Foil gas storage device according to one of the preceding claims, wherein the recesses (17) define a flow path axially inward, which predefined flow path ends at an unstructured axial section (17.6).

4. foil gas storage device according to one of the preceding claims, wherein the recesses (17) on both sides from axially outside to axially inside to an unstructured axial section (17.6) of the foil gas storage device (10) and end there at an axial distance from one another; and / or where the

Recesses (17) are set up to build up a pressure in / in the unstructured axial section (17.6) of the foil gas bearing device; and / or wherein the recesses (17) are provided in full; and / or where the

Recesses (17) are designed as grooves or as grooves.

5. Foil gas storage device according to one of the preceding claims, wherein the recesses (17) are arranged in two axial sections (17.4, 17.5) and are oriented in opposite directions, in particular in each case with a spiral course, in particular at least approximately the same amount relative to the axial direction;

and / or wherein the recesses (17) form two structured axial sections (17.4, 17.5) which delimit an unstructured axial section (17.6) arranged between them, the two axial sections and the unstructured axial section arranged between them over the entire axial length of the Rotor and / or the top film device are provided; and / or wherein the recesses (17) extend from an outer edge (12.3, 14.3) of the top film device and / or of the rotor and extend axially inwards.

6. Foil gas storage device according to one of the preceding claims, wherein the recesses (17) are curved at least in sections; and / or wherein the recesses (17) run at least in sections in a spiral shape; and / or wherein the respective recess (17) extends at least in sections in a straight line without curvature, in particular axially on the outside.

7. foil gas storage device according to one of the preceding claims, wherein the foil gas storage device (10) is set up for oil-free radial mounting of the rotor (12) exclusively by means of gas (G), in particular by means of air; and / or wherein the top film device (14) is flexible; and / or wherein the recesses (17) of the top film device can be arranged statically.

8. Use of a foil gas storage device, in particular one

Foil gas bearing device (10) according to one of the preceding claims, for the radial bearing of a rotor oil-free exclusively by means of gas, a top foil device (14) of the foil gas bearing device being arranged relative to the rotor (12) and relative to the direction of rotation of the rotor such that on the top (14a) of the top film device (14) and / or on the top (12a) of the rotor (12) arranged or incorporated therein recesses (17) obliquely to the axial direction (x) and obliquely to the circumferential direction (a) and at least one axial section (17.3, 17.4, 17.5) of the bearing are arranged and set up to build up a pressure in a radial gap (13) of the bearing formed between the rotor and the top film device and in particular also in an unstructured axial section (17.6), in particular Use of the foil gas storage device in a heat pump or in a device with a heat pump.

9. foil gas storage device, in particular foil gas storage device (10) according to one of the preceding device claims, produced by structuring the top foil device (14) and / or the rotor (12) on the respective upper side (14a, 12a)

a plurality of recesses (17) running obliquely to the axial direction (x) and obliquely to the circumferential direction (a), which are arranged in at least one axial section of the bearing in such a way that the foil gas bearing device (10) is set up to build up a pressure in between the rotor (12) and the top film device (14) formed radial gap (13) of the bearing and in particular also in an unstructured axial section (17.6).

10. A method for providing a film gas storage device, in particular a film gas storage device (10) according to one of the preceding

Device claims for supporting a rotor (12) by means of gas (G), with the steps:

Providing a bump film device (15) which can be supported on a carrier (16) in a bearing bush (1) for supporting a top film device in the radial direction;

Arranging and fastening the top film device (14) on the bump film device (15) for the radial mounting of the rotor;

g e k e n n e i c h n t through the steps:

wherein the top film device is arranged in such a way that a plurality of recesses (17) of the film gas storage device (10) which run obliquely to the axial direction (x) and obliquely to the circumferential direction (a) and which are located on the top of the top film device and / or are provided on the rotor (12), are arranged in at least one axial section of the bearing and are set up to build up a pressure in a between the rotor and the top film device (10) formed radial gap (13) of the bearing, in particular also in an unstructured axial section (17.6).