Bearing system for rotary atomizers

Abstract

The present invention relates to a bearing system for a drive turbine of a rotary sprayer (1), comprising a rotatable turbine shaft (3) for receiving a bell cup (2) used to spray paint, and radial bearings (13-15) for rotatably supporting the turbine shaft (3). The present invention provides that the radial bearing comprises at least one foil bearing (12) or spiral groove bearing.

Description

[Technical Field]

[0001] The present invention relates to a bearing system for a drive turbine of a rotary atomizer. [Background technology]

[0002] Modern paint installations for painting automotive body parts typically use rotary atomizers as the applicator. A so-called bell cup rotates at high speed to shake off the paint to be applied from the bell cup's spray rim. The bell cup is driven by a compressed air turbine having a rotatably mounted turbine shaft with a bell cup at its end. The turbine shaft is typically supported by a hydrostatic air bearing.

[0003] One drawback of using hydrostatic air bearings to support the turbine shaft is that compressed air of high purity, i.e., with low oil content and few and small sized solid particles, is required.

[0004] Another drawback of known air bearings is their sensitivity to shock forces.

[0005] Furthermore, known air bearings also have limited emergency operating characteristics.

[0006] For the technical background of the present invention, please refer to US Pat. No. 5,629,499, US Pat. No. 5,629,499, as well as the Wikipedia articles "Spiral groove bearing" and "Foil bearing." [Prior art documents] [Patent documents]

[0007] [Patent Document 1] US Patent Application Publication No. 2003 / 0169951 [Patent Document 2] U.S. Patent No. 9,970,481 Summary of the Invention [Problem to be solved by the invention]

[0008] The invention is therefore based on the problem of providing an improved bearing system for supporting a turbine shaft in a rotary atomizer. [Means for solving the problem]

[0009] This problem is solved by a bearing system according to the invention as set forth in the main claim.

[0010] Firstly, following the prior art, the bearing system according to the invention comprises a rotatable turbine shaft serving to receive a bell cup, which can be screwed onto the end of the turbine shaft, for example as known per se from the prior art.

[0011] Furthermore, in keeping with the prior art, the bearing system according to the invention also includes at least one radial bearing for rotatably supporting the turbine shaft.

[0012] The invention is characterized in that the radial bearing comprises at least one foil bearing. Such foil bearings are known per se from the prior art (see, for example, the Wikipedia article "Foil bearing"). However, their use for supporting a turbine shaft in a rotary atomizer has not previously been proposed. A particular feature of this is the wide operating range in view of the low available starting torque and speed of the atomizer turbine.

[0013] Alternatively, the radial bearing can be formed by at least one spiral groove bearing, also called a spiral slot bearing.

[0014] In a preferred embodiment of the invention, the foil bearing first comprises a cover foil that is substantially cylindrical or free-formed and surrounds the turbine shaft.

[0015] Furthermore, the foil bearing preferably includes a spring foil that is substantially cylindrical and at least partially surrounds the cover foil, the spring foil exerting a radially inward spring force on the cover foil.

[0016] For example, the spring foil may have a variation of ±50%, ±25%, ±10%, or ±5%. 9 N / m 3 The surface stiffness may be

[0017] Furthermore, the foil bearing preferably has a bearing shell that encases the spring foils, the spring foils being supported on the outside of the bearing shell and pressing the cover foils radially inward. The bearing shell may be cylindrical or have multiple arcs, for example.

[0018] For example, the spring foil may be formed as a wire mesh, as a corrugated foil with protruding bumps, as a metal foil with a bent structure, or as an elastomeric foil, to name a few.

[0019] Furthermore, it should be mentioned that the spring foil can be manufactured by etching, although other methods are also possible.

[0020] Furthermore, it should be mentioned that the cover foil may be coated with a wear-reducing coating on the turbine shaft side (i.e., inside) to reduce friction and wear during operation.

[0021] Furthermore, it should be mentioned that the bearing shell and the cover foils may have different radii distributed on the periphery, as is also known for example from hydrodynamic air bearings.

[0022] The turbine shaft is preferably mechanically driven by a compressed air turbine having a rotatable turbine wheel, which thus has a drive air supply for providing drive air for driving the turbine wheel, and further has an exhaust guide for discharging the expanded drive air from the compressed air turbine, as known per se from the prior art.

[0023] In this case, it is also possible for the supplied drive air and / or the exhaust air to be partially guided through the foil bearing, for example radially from the outside in. Thus, the drive air supply can branch off a portion of the drive air and guide it through the foil bearing.

[0024] Additionally, expanded drive air from the exhaust supply can be directed, for example axially, through the foil bearing.

[0025] The spring foils, cover foils and / or bearing shells may have radially passing holes therethrough that allow the diverted drive air to pass radially from outside to inside.

[0026] In a preferred embodiment of the present invention, the radial bearing does not include only a single foil bearing, but also at least two foil bearings, which may be axially adjacent to one another or spaced apart from one another, e.g., spacer rings may be arranged between adjacent foil bearings.

[0027] For example, the two foil bearings may be arranged on different sides of the turbine wheel of the compressed air turbine. In another embodiment of the invention, on the contrary, the two foil bearings are arranged on the same side of the turbine wheel of the compressed air turbine.

[0028] The above description essentially relates to the design of the radial bearing as a foil bearing. Furthermore, the bearing system according to the invention preferably comprises an additional axial bearing which also supports the turbine shaft in the axial direction. This axial bearing is preferably designed as an aerodynamic spiral groove bearing, which spiral groove bearings are known from the prior art. See, for example, the Wikipedia article "Spiral groove bearing."

[0029] Therefore, the spiral groove bearing preferably first includes a rotating disk that is torsionally fixedly connected to the turbine shaft and rotates together with the turbine shaft during operation. The spiral groove bearing further includes a first stationary disk fixedly arranged in the bearing system, the rotating disk and the first stationary disk being adjacent to each other in a substantially planar parallel relationship. The first stationary disk preferably has a spiral groove on its end face, as is known per se from conventional spiral groove bearings.

[0030] In a preferred embodiment of the invention, the spiral groove bearing additionally comprises a second stationary disk fixedly arranged in the bearing system, the rotating disk and the second stationary disk being adjacent to each other in a substantially planar parallel manner, and a plurality of spiral grooves are also arranged on the end face of the second stationary disk facing the rotating disk or the stationary disk, which are known per se from conventional spiral groove bearings and therefore do not require a detailed description.

[0031] The two stationary discs are preferably axially preloaded, i.e. pressed against one another, by at least one spring.

[0032] Between the two stationary discs there is preferably a spacer (eg, a spacer bolt), which adjusts the axial distance between the two stationary discs to reduce starting friction.

[0033] The above-mentioned rotating disk of the spiral groove bearing may, for example, be formed by the turbine wheel or may be torsionally fixedly connected to the turbine wheel. In a preferred embodiment of the invention, the spiral groove bearing is arranged on both sides of the turbine wheel. In this way, the axial bearing also acts as a seal and reduces leakage losses of the turbine.

[0034] In one variant of the invention, the bearing shell of the foil bearing has a substantially constant internal cross section in the axial direction, while the cover foil of the foil bearing has an internal cross section that tapers in the circumferential direction, thereby forming a plurality of wedges, which may be formed not only by the shape of the spring foil but also by the bearing shell.

[0035] On the other hand, in another variant of the invention, the bearing shell and the cover foil of the foil bearing each have an internal cross section that tapers axially, in particular conically, towards the bell cup.

[0036] Overall, it should be mentioned that the bearing system according to the present invention preferably generates at least 50 W, 100 W, 200 W, or 300 W of frictional heat during operation to avoid condensation within the bearing system.

[0037] It should further be mentioned that the spring foils of the foil bearing allow a specific radial spring movement, while the spring foils have a specific bearing diameter, and the ratio between said spring movement and said bearing diameter is preferably less than 0.1, 0.05, 0.01, 0.005, or 0.0033.

[0038] It should further be mentioned that the bearing system may include a labyrinth seal for sealing the rotatable turbine shaft, which preferably surrounds the turbine shaft annularly and is located at the distal end of the turbine shaft, i.e., on the front side where the bell cup can be attached.

[0039] In the bearing system according to the present invention, the radial bearing may comprise an aerostatic air bearing in which the supplied compressed air forms an air cushion for the bearing, or alternatively, the radial bearing may comprise an aerodynamic air bearing in which the air cushion for the bearing is generated by the movement of the air bearing.

[0040] Finally, it should be mentioned that the present invention does not only claim protection for the above-mentioned bearing system, but rather also claims protection for a complete rotary atomizer having such a bearing system for supporting the turbine shaft.

[0041] Further advantages of further embodiments of the invention are set out in the dependent claims and will be explained in more detail below together with the description of preferred embodiments of the invention with reference to the drawings. [Brief explanation of the drawings]

[0042] [Figure 1] 1 is a schematic cross-sectional view of a rotary atomizer according to the present invention. [Figure 2] FIG. 2 is a front view of the stationary disk of the spiral groove bearing of the rotary atomizer of FIG. 1; [Figure 3A] 3 is a schematic cross-sectional view of another embodiment of a rotary atomizer according to the present invention; FIG. [Figure 3B] Enlarged detail of Figure 3A. [Figure 4A] 3B is a modification of the embodiment according to FIG. 3A. [Figure 4B] Enlarged detail of Figure 4A. [Figure 5] 1 is a simplified schematic cross-sectional view of a foil bearing according to the present invention; [Figure 6] A modification of the foil bearing in FIG. 6. [Figure 7] Schematic cross-sectional view of a spiral groove bearing for use as an axial bearing. [Figure 8] 2A to 2C show various modifications of the embodiment according to FIG. 1. [Figure 9] 2A to 2C show various modifications of the embodiment according to FIG. 1. [Figure 10] 2A to 2C show various modifications of the embodiment according to FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0043] 1 shows a simplified schematic diagram of a rotary sprayer 1 according to the present invention, which can be used, for example, to deliver paint to be applied in a painting system for painting automotive body parts. To this end, rotary sprayer 1 includes a bell cup 2, which is attached to a turbine shaft 3 and rotates at high speed about axis of rotation 4 during a painting operation.

[0044] The rotary atomizer 1 is conventionally driven by a compressed air turbine having a turbine wheel 5 which projects radially from the turbine shaft 3 and has turbine blades 6 at its end. In operation, the turbine wheel 5 with its turbine blades 6 is fed with drive air by an air supply 7. Within the rotary atomizer 1, a drive air line 8 branches off from the air supply 7 and is directed towards the turbine blades 6.

[0045] Axialwise, the turbine wheel 5 is adjacent to two fixed stationary discs 9, 10, which are plane-parallel to the end faces of the turbine wheel 5 and form, together with the turbine wheel 5, a spiral groove bearing for axially supporting the turbine shaft 3. For this purpose, as shown in FIG. 2 with reference to the stationary disc 9, the two stationary discs 9, 10 each have a spiral groove 11 on the side facing the turbine wheel 5. Thus, together with the turbine wheel 5, the two stationary discs 9, 10 form an axial bearing within the rotary atomizer 1.

[0046] Furthermore, the rotary atomizer 1 also includes a radial bearing for supporting the turbine shaft 3. The radial bearing is designed as a foil bearing 12 and includes a cover foil 13, a spring foil 14, and a bearing shell 15, the bearing shell 15 being formed by the atomizer housing. The spring foil 14 is mounted between the bearing shell 15 and the cover foil 13. The spring foil 14 rests against the outside of the bearing shell 15 and presses the cover foil 13 inward. The foil bearing 12 is basically known in terms of its structure and operation from the prior art, and therefore will not be described in detail.

[0047] One of the advantages of the novel use of foil bearings 12 in rotary atomizer 1 is its lower susceptibility to the action of impact forces.

[0048] It should be mentioned that a bearing air line 16 branches off from the air supply 7 to introduce part of the drive air radially from outside to inside into the foil bearing 12 .

[0049] Furthermore, it should be mentioned that the rotary atomizer 1 has a labyrinth seal 17 at the distal end of the turbine shaft (but within the rotary atomizer 1).

[0050] Figures 3A and 3B show cross-sectional views of another embodiment of a rotary atomizer 1 according to the invention, which largely corresponds to the previous embodiment illustrated in Figures 1 and 2, so that to avoid repetition reference is made to the previous description and the same reference numerals are used for corresponding details.

[0051] A special feature of this embodiment is that two foil bearings 12.1, 12.2 are provided to support the turbine shaft 3. In this case, the two foil bearings 12.1, 12.2 are arranged axially next to each other and sandwich only an air gap 18 between them, the function of which will be explained in more detail below.

[0052] The two foil bearings 12.1, 12.2 have bearing shells 15.1, 15.2 respectively, which have radially extending through holes 19.1, 19.2 to allow bearing air supplied from a bearing air line 16 to pass radially through the bearing shells 15.1, 15.2 as shown by the arrows. The supplied bearing air then leaks out again through an air gap 18 as shown by the arrows.

[0053] Figures 4A and 4B show a variant of the embodiment according to Figures 3A and 3B, to avoid repetition reference being made to the previous description of Figures 3A and 3B. A special feature of this embodiment is that the two foil bearings 12.1, 12.2 are arranged on different sides of the turbine wheel 5.

[0054] Furthermore, as can be seen in FIG. 4B, part of the expanded exhaust of the compressed air turbine can be conducted through the foil bearings 12.1, 12.2.

[0055] Figure 5 shows a simplified schematic cross-sectional view of a foil bearing 12 according to the present invention, which for the most part corresponds to the embodiment of the foil bearing 12 described above, so that to avoid repetition, reference is made to the previous description and the same reference numerals are used for corresponding details.

[0056] In the embodiment according to FIG. 5, the bearing shell 15 and the cover foil 13 each have an internal cross section that tapers conically in the axial direction towards the bell cup 2 .

[0057] 6, on the other hand, the bearing shell 15 has a substantially constant internal cross section in the axial direction, except that the cover foil 13 now has an internal cross section that tapers conically in the axial direction towards the bell cup 2.

[0058] Finally, Figure 7 shows a further embodiment of a spiral groove bearing for a turbine shaft 3 according to the invention, which partly corresponds to the previous embodiment, so that to avoid repetition reference is made to the previous description and the same reference numerals are used for corresponding details.

[0059] Here, the spiral groove bearing includes a rotating disc 20 that projects radially from the turbine shaft 3 and rotates together with the turbine shaft 3 .

[0060] On either side of the rotating disc 20 there are two plane-parallel stationary discs 21, 22 which lie plane-parallel to the end faces of the rotating disc 20 and each contain a spiral groove, as known per se from conventional spiral groove bearings.

[0061] The axial distance between the two stationary discs 21, 22 is adjusted by a spacer bolt 23 to reduce starting friction.

[0062] It should be mentioned here that the two stationary discs 21 , 22 are preloaded by two springs 24 , 25 , i.e. the two springs 24 , 25 press the two stationary discs 21 , 22 against the rotating disc 20 .

[0063] 8-10 show different variants of the embodiment according to FIG. 1, and therefore, to avoid repetition, reference is made to the previous description and the same reference numerals are used for corresponding details.

[0064] In the variant according to FIG. 8, a special feature is that the spiral groove bearing 26 serves as an axial bearing, while the further spiral groove bearing 27 forms the radial bearing.

[0065] In the variant according to FIG. 9, a special feature is that the foil bearing 28 serves as the axial bearing, while the spiral groove bearing 29 forms the radial bearing.

[0066] In the variant according to FIG. 10, a special feature is that foil bearing 30 serves as an axial bearing, while foil bearing 31 also forms a radial bearing.

[0067] Therefore, the present invention allows any combination of spiral groove bearings and foil bearings as axial or radial bearings.

[0068] The present invention is not limited to the preferred embodiment described above. Rather, numerous variations and modifications are possible that utilize the concepts of the present invention and are therefore within the scope of the present invention. In particular, the present invention claims protection for the subject matter and features of the dependent claims independently of the claims to which they refer, and in particular without the features of the main claim. And the present invention includes different aspects of the invention that enjoy protection independently of each other.

[0069] [Note] [Appendix 1] A bearing system for a drive turbine of a rotary sprayer (1) for the application of paint, comprising: a) a rotatable turbine shaft (3) for receiving a bell cup (2) used to spray the paint; b) a radial bearing for rotatably supporting the turbine shaft (3); and A bearing system, characterized in that the radial bearing comprises at least one foil bearing (12, 12.1, 12.2) or spiral groove bearing (27; 29).

[0070] [Appendix 2] The foil bearings (12, 12.1, 12.2) are a) a cover foil (13, 13.1, 13.2) that is substantially cylindrical and surrounds the turbine shaft (3); b) spring foils (14, 14.1, 14.2) that are substantially cylindrical and at least partially surround the cover foils (13, 13.1, 13.2), the spring foils (14, 14.1, 14.2) exerting a radially inward spring force on the cover foils (13, 13.1, 13.2), and preferably having a surface stiffness of substantially 1·109 N / m³ ±50%, ±25%, ±10%, or ±5%; c) a bearing shell (15, 15.1, 15.2) encasing said spring foil (14, 14.1, 14.2), said bearing shell (15, 15.1, 15.2) optionally being cylindrical or optionally having a plurality of circular arcs; 2. The bearing system of claim 1, comprising:

[0071] [Appendix 3] a) the spring foils (14, 14.1, 14.2) are a1) As wire mesh, a2) a bump foil having a bump protruding into the spring foil (14, 14.1, 14.2), a3) as a metal foil with a bent structure, or a4) as an elastomer foil, formed, and / or b) said spring foils (14, 14.1, 14.2) are produced by etching; and / or c) said cover foils (13, 13.1, 13.2) are coated with a wear-reducing coating, and / or d) the cover foils (13, 13.1, 13.2) have two different radii distributed around the circumference; 10. A bearing system as described in appended claim 2.

[0072] [Appendix 4] a) a compressed air turbine having a rotatable turbine wheel (5) for driving said turbine shaft (3); b) a drive air supply (7, 8) for supplying drive air for driving the turbine wheel (5); c) an exhaust guide for discharging the expanded driving air from the compressed air turbine; 4. A bearing system according to any one of claims 1 to 3, comprising:

[0073] [Appendix 5] a) the drive air supply of the compressed air turbine branches off a portion of the drive air and directs it through the foil bearings (12, 12.1, 12.2), in particular radially from the outside to the inside; and / or b) the exhaust guide of the compressed air turbine guides the expanded driving air at least partially through the foil bearings (12, 12.1, 12.2), in particular axially; 10. A bearing system as described in claim 4.

[0074] [Appendix 6] 6. The bearing system according to claim 5, wherein the spring foils (14, 14.1, 14.2) and / or the cover foils (13, 13.1, 13.2) and / or the bearing shells (15, 15.1, 15.2) have radially penetrating holes for guiding the branched driving air radially from the outside to the inside.

[0075] [Appendix 7] a) the radial bearing comprises at least two foil bearings (12, 12.1, 12.2) arranged axially, in particular with a spacer ring between adjacent foil bearings (12, 12.1, 12.2); b) the two foil bearings (12, 12.1, 12.2) are arranged on different sides or on the same side of the turbine wheel (5) of the compressed air turbine; 7. A bearing system according to any one of clauses 1 to 6.

[0076] [Appendix 8] 8. A bearing system according to any one of claims 1 to 7, comprising at least one additional axial bearing for supporting the turbine shaft (3), the axial bearing preferably comprising at least one spiral groove bearing or other bearing, in particular a Rayleigh step bearing.

[0077] [Appendix 9] a) the axial bearing comprises a spiral groove bearing (9-11) and the radial bearing comprises a foil bearing (12), or b) the axial bearing comprises a spiral groove bearing (26) and the radial bearing comprises a spiral groove bearing (27), or c) the axial bearing comprises a foil bearing (28) and the radial bearing comprises a spiral groove bearing (29); or d) the axial bearing comprises a foil bearing (30) and the radial bearing comprises a foil bearing (31); 10. A bearing system as described in claim 8.

[0078] [Appendix 10] The axial bearing is a) a rotating disc (5, 20) that is torsionally fixedly connected to the turbine shaft (3) and that rotates together with the turbine shaft (3) during operation; b) a first stationary disc (9, 21) fixedly arranged within said bearing system; 10. The bearing system of claim 8 or 9, wherein the rotating disc (5, 20) and the first stationary disc (9, 21) are adjacent to each other in a substantially planar parallel relationship.

[0079] [Appendix 11] a) the axial bearing has a second stationary disc (10, 22) fixedly arranged within the bearing system, the rotating disc (5, 20) and the second stationary disc (10, 22) being adjacent to each other in a substantially planar parallel relationship; b) the two said stationary discs (21, 22) are preferably axially preloaded against each other by at least one elastic element (24, 25); c) spacers (23), preferably arranged between the two stationary discs (21, 22), in particular in the form of spacer bolts (23), which adjust the axial distance between the two stationary discs (21, 22) in order to reduce starting friction; 11. The bearing system of claim 9 or 10.

[0080] [Appendix 12] a) the rotating disk (5, 20) of the axial bearing is preferably torsionally fixedly connected to the turbine wheel (5) of the compressed air turbine or is formed by the turbine wheel (5), in particular with a spiral on the stator side, and / or b) spiral axial bearings are preferably arranged axially on both sides of the turbine wheel (5); 12. A bearing system according to any one of clauses 9 to 11.

[0081] [Appendix 13] a) the bearing shell (15, 15.1, 15.2) has a substantially constant internal cross section in the axial direction, while the cover foil (13, 13.1, 13.2) has an internal cross section that tapers circumferentially or axially, in particular conically, towards the bell cup (2), or b) the bearing shells (15, 15.1, 15.2) and the cover foils (13, 13.1, 13.2) each have an internal cross section that tapers axially, in particular conically, towards the bell cup (2); 13. A bearing system according to any one of clauses 2 to 12.

[0082] [Appendix 14] a) the bearing system generates at least 50 W, 100 W, 200 W, or 300 W of frictional heat during operation at full load to avoid condensation within the bearing system; and / or b) the spring foils (14, 14.1, 14.2) allow a specific radial spring travel, while the spring foils (14, 14.1, 14.2) have a specific bearing diameter, and the ratio of the spring travel to the bearing diameter is less than 0.1, 0.05, 0.01, 0.005, or 0.0033; 14. A bearing system according to any one of clauses 1 to 13.

[0083] [Appendix 15] a) the bearing system has a labyrinth seal (17) for sealing the turbine shaft (3); b) the labyrinth seal (17) surrounds the turbine shaft (3), preferably annularly; c) the labyrinth seal (17) is preferably arranged axially between the bell cup (2) and the radial bearing; d) the labyrinth seal optionally has a ring-shaped or spiral groove-shaped structure; 15. A bearing system according to any one of clauses 1 to 14.

[0084] [Appendix 16] a) the radial bearing comprises an aerostatic air bearing in which the supplied compressed air forms an air cushion for the bearing; or b) the radial bearing includes an air dynamic pressure air bearing, in which an air cushion for the bearing is generated by movement of the air bearing; 16. The bearing system of any one of clauses 1 to 15.

[0085] [Appendix 17] A rotary atomizer (1) having a bearing system according to any one of claims 1 to 16. [Explanation of symbols]

[0086] 1 rotary sprayer 2 Bell Cups 3 Turbine shaft 4 Bell cup rotation axis 5. Spiral groove bearing turbine wheel and rotating disc 6. Turbine blades 7 Air supply for drive air and bearing air 8 Drive Air Line 9, 10 Stationary disc of spiral groove bearing 11 Spiral groove on the stationary disk of a spiral groove bearing 12, 12.1, 12.2 Foil bearings for turbine shaft support 13, 13.1, 13.2 Cover foil 14, 14.1, 14.2 Spring foil 15, 15.1, 15.2 bearing shells 16 Bearing Air Line 17 Labyrinth Seal 18 Air gap between two foil bearings 19.1, 19.2 Holes in bearing shell for supplying bearing air 20 Spiral groove bearing rotating disc 21, 22 Stationary disc of spiral groove bearing 23 Spacer bolts between stationary discs of spiral groove bearings 24, 25 Spring for axial preload of stationary disc of spiral groove bearing 26 Spiral groove bearing as an axial bearing 27 Spiral groove bearings as radial bearings 28 Foil bearings as axial bearings 29 Spiral Groove Bearings as Radial Bearings 30 Foil bearings as axial bearings 31 Foil bearings as radial bearings

Claims

1. A bearing system for a drive turbine of a rotary sprayer (1) for the application of paint, comprising: a) a rotatable turbine shaft (3) for receiving a bell cup (2) used to spray the paint; b) a radial bearing for rotatably supporting the turbine shaft (3); c) a compressed air turbine having a rotatable turbine wheel (5) for driving said turbine shaft (3); d) a drive air supply (7, 8) for supplying drive air for driving said turbine wheel (5); e) an exhaust guide for discharging the expanded driving air from the compressed air turbine; and f) said radial bearing comprises at least one foil bearing (12, 12.1, 12.2); g) g1) the drive air supply of the compressed air turbine branches off a portion of the drive air and directs it through the foil bearing (12, 12.1, 12.2); and / or g2) A bearing system, characterized in that the exhaust guide of the compressed air turbine guides the expanded driving air at least partially through the foil bearings (12, 12.1, 12.2).

2. 2. A bearing system according to claim 1, comprising at least one additional axial bearing for supporting the turbine shaft (3).

3. The axial bearing is a) a rotating disc (5, 20) that is torsionally fixedly connected to the turbine shaft (3) and that rotates together with the turbine shaft (3) during operation; b) a first stationary disc (9, 21) fixedly arranged within said bearing system; 3. A bearing system according to claim 2, wherein the rotating disc (5, 20) and the first stationary disc (9, 21) are adjacent to each other in a substantially planar parallel relationship.

4. A bearing system as described in claim 3, characterized in that the axial bearing has a second stationary disk (10, 22) fixedly arranged within the bearing system, and the rotating disk (5, 20) and the second stationary disk (10, 22) are adjacent to each other so as to be substantially planarly parallel.

5. 5. A bearing system according to claim 1, wherein the spring foils (14, 14.1, 14.2) and / or the cover foils (13, 13.1, 13.2) and / or the bearing shells (15, 15.1, 15.2) have radially penetrating holes for directing the branched driving air radially from the outside to the inside.

6. a) the axial bearing comprises a spiral groove bearing (9-11) and the radial bearing comprises a foil bearing (12), or b) the axial bearing comprises a spiral groove bearing (26) and the radial bearing comprises a spiral groove bearing (27), or c) the axial bearing comprises a foil bearing (28) and the radial bearing comprises a spiral groove bearing (29); or d) the axial bearing comprises a foil bearing (30) and the radial bearing comprises a foil bearing (31); A bearing system according to any one of claims 2 to 4.

7. a) the rotating disk (5, 20) of the axial bearing is torsionally fixedly connected to or formed by the turbine wheel (5) of a compressed air turbine, and / or b) spiral axial bearings are arranged axially on both sides of the turbine wheel (5); 5. A bearing system according to claim 3 or 4.

8. a) the foil bearings (12, 12.1, 12.2) comprise bearing shells (15, 15.1, 15.2) and cover foils (13, 13.1, 13.2); b) b1) the bearing shell (15, 15.1, 15.2) has a substantially constant internal cross section in the axial direction, while the cover foil (13, 13.1, 13.2) has an internal cross section that tapers circumferentially or axially towards the bell cup (2), or b2) the bearing shells (15, 15.1, 15.2) and the cover foils (13, 13.1, 13.2) each have a tapered internal cross section; A bearing system according to any one of claims 1 to 7.

9. A bearing system for a drive turbine of a rotary sprayer (1) for the application of paint, comprising: a) a rotatable turbine shaft (3) for receiving a bell cup (2) used to spray the paint; b) a radial bearing for rotatably supporting the turbine shaft (3); and c) said radial bearing comprises at least one foil bearing (12, 12.1, 12.2); d) the foil bearings (12, 12.1, 12.2) comprise bearing shells (15, 15.1, 15.2) and cover foils (13, 13.1, 13.2); e) e1) the bearing shell (15, 15.1, 15.2) has a substantially constant internal cross section in the axial direction, while the cover foil (13, 13.1, 13.2) has an internal cross section that tapers circumferentially or axially towards the bell cup (2), or e2) A bearing system characterized in that said bearing shell (15, 15.1, 15.2) and said cover foil (13, 13.1, 13.2) each have a tapered internal cross section.

10. The foil bearings (12, 12.1, 12.2) are a) a cover foil (13, 13.1, 13.2) that is substantially cylindrical and surrounds the turbine shaft (3); b) spring foils (14, 14.1, 14.2) that are substantially cylindrical and at least partially surround the cover foils (13, 13.1, 13.2), the spring foils (14, 14.1, 14.2) exerting a radially inward spring force on the cover foils (13, 13.1, 13.2); c) bearing shells (15, 15.1, 15.2) enclosing the spring foils (14, 14.1, 14.2); 10. A bearing system according to any one of claims 1 to 9, comprising:

11. a) said spring foils (14, 14.1, 14.2) a1) as a wire mesh, a2) a bump foil having a bump protruding into the spring foil (14, 14.1, 14.2), a3) as a metal foil with a bent structure, or a4) as an elastomer foil, formed, and / or b) said spring foils (14, 14.1, 14.2) are produced by etching; and / or c) said cover foils (13, 13.1, 13.2) are coated with a wear-reducing coating, and / or d) said cover foils (13, 13.1, 13.2) have two different radii distributed on the circumference; 11. The bearing system of claim 10.

12. a) the radial bearing comprises at least two foil bearings (12, 12.1, 12.2) arranged axially; b) the two foil bearings (12, 12.1, 12.2) are arranged on different sides or on the same side of the turbine wheel (5) of the compressed air turbine; A bearing system according to any one of claims 1 to 11.

13. The bearing system generates frictional heat during operation at a rate of at least 50 W at full load to avoid condensation within the bearing system. A bearing system according to any one of claims 1 to 12.

14. a) the bearing system has a labyrinth seal (17) for sealing against the turbine shaft (3); b) the labyrinth seal (17) surrounds the turbine shaft (3); A bearing system according to any one of claims 1 to 13.

15. a) the radial bearing comprises an aerostatic air bearing in which the supplied compressed air forms an air cushion for the bearing; or b) the radial bearing includes an air dynamic pressure air bearing, in which an air cushion for the bearing is generated by movement of the air dynamic pressure air bearing; A bearing system according to any one of claims 1 to 14.

16. A rotary atomizer (1) comprising a bearing system according to any one of claims 1 to 15.

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