EP2552595A1

EP2552595A1 - Axial turbine for a rotary atomizer

Info

Publication number: EP2552595A1
Application number: EP11708997A
Authority: EP
Inventors: Michael Baumann; Marcus Frey; Frank Herre; Bernhard Seiz; Harry Krumma; Timo Beyl; Stephan Scholl; Jürg SCHIFFMANN
Original assignee: Duerr Systems AG
Current assignee: Duerr Systems AG
Priority date: 2010-03-31
Filing date: 2011-03-02
Publication date: 2013-02-06
Anticipated expiration: 2031-03-02
Also published as: JP2017018956A; JP6097683B2; US20130017068A1; CN102834183B; DE102010013551B4; JP2013527793A; CN102834183A; DE102010013551A1; DE102010013551A8; EP2552595B1; US9604232B2; WO2011120619A1; ES2612904T3; JP6282701B2

Abstract

The invention relates to a turbine rotor (17) for a drive turbine (10) of a rotary atomizer (38), having a rotatably supported turbine shaft (17) having the potential for mounting an atomizer wheel, and having at least one drive turbine wheel (4-6; 25-27) having a plurality of turbine blades (34), wherein the turbine blades of the drive turbine wheel are impinged on during operation by a drive fluid in order to drive the turbine rotor (17). The invention proposes that the drive turbine wheel is designed for the drive fluid to axially impinge on the turbine blades. The invention further relates to a complete drive turbine (10) having such a turbine rotor and to a complete rotary atomizer and individual components of the drive turbine (10) according to the invention.

Description

DESCRIPTION Axial turbine for a rotary atomizer

The invention relates to a turbine rotor for driving a rotary atomizing turbine and a drive turbine with such a turbine rotor and other components of a rotary nungs, such as a bearing unit, an intermediate sleeve, a deflection ring and a stator.

In modern paint shops for painting automotive body components, rotary atomizers are usually used as the application device, which have a bell cup as the application element, which is well known from the prior art. The drive of the conventional rotary atomizers is usually carried out pneumatically by a drive turbine, which is blown with compressed air, wherein the drive turbine is designed as a radial turbine.

This means that the compressed air serving as drive fluid flows in a plane aligned radially to the rotational axis of the bell cup onto the turbine blades of the drive turbine. The use of a radial turbine to drive a rotary atomizer offers the advantage that the required drive torque can be achieved by using a drive turbine wheel with a correspondingly large diameter. A disadvantage of using a radial turbine to drive a rotary atomizer, however, is the limited drive power, resulting in a sufficiently fine atomization in the speed range of 8000-80. OOOU / min. can hardly increase more than 650, which also causes the Lackausflussrate to values of about 1000 ml / min. is limited. This fundamental disadvantage of a radial turbine can not be remedied by an enlargement of the radial turbine, as this is not possible due to space and weight reasons. An increase of the maximum possible drive power by raising the pressure level or the air flow rate of the drive air is practically impossible since this leads to higher capital expenditures. Operating costs would result. The invention is therefore based on the object at a

Rotationszerstäuberturbine to increase the maximum possible drive power.

This object is achieved by a turbine rotor according to the invention according to the main claim. In addition, the invention also includes a complete drive turbine with such a turbine rotor according to the invention. Furthermore, the invention also includes further components of a rotary atomizer adapted according to the invention, such as an intermediate sleeve, a bearing unit, a drive turbine wheel, a deflection ring and a stator ring.

The invention comprises the general technical teaching of using a rotary atomizer for driving a rotary atomizer, in which the drive fluid (for example compressed air) axially flows the turbine blades of the drive turbine wheel, i. parallel to the axis of rotation of the bell plate.

The invention therefore comprises a turbine rotor with a rotatably mounted turbine shaft with a mounting option for a bell cup. One way to mount the bell cup on the turbine shaft is that the bell cup is screwed onto the turbine shaft serving as the bell shaft, which is known from the prior art is well known. Another possibility for mounting the bell cup on the bell shaft serving as the turbine shaft is that the bell cup is fixed by a clamping or latching connection to the turbine shaft, as described for example in DE 10 2009 034 645, so that the content of this patent application of This description of the assembly of the bell cup on the turbine shaft is fully attributable. However, the invention is not limited to the above-mentioned examples with regard to the mounting of the bell cup on the turbine shaft, but basically also allows other types of installation.

In addition, the turbine rotor of the present invention includes at least one turbine impeller having a plurality of turbine blades, the turbine blades of the power turbine impeller being impelled by a drive fluid (e.g., compressed air) during operation to drive the turbine rotor. It is important here that the drive turbine wheel is connected to the turbine shaft in a manner safe against rotation in order to be able to transmit torque from the drive turbine wheel to the turbine shaft. One possibility for this is that the turbine shaft and the drive turbine wheel are made in one piece as a single component. In the context of the invention, however, it is alternatively also possible for the drive turbine wheel and the turbine shaft to be separate components which are connected to one another only in a manner secured against rotation.

The invention now provides that the drive turbine wheel for an axial flow of the turbine blades with the

Drive fluid is designed. In contrast, the drive turbine wheels are designed in the conventional radial turbine for a radial flow of the turbine blades. This departure from the conventional principle of a radial turbine to the principle according to the invention of an axial turbine advantageously makes it possible to increase the maximum possible drive power since the axial turbine according to the invention can have a plurality of drive turbine wheels (stages) arranged one behind the other.

In a preferred exemplary embodiment of the invention, the turbine rotor therefore has a plurality of (eg 2, 3, 4 or 5) drive turbine wheels arranged axially one behind the other, the individual drive turbine wheels each having a plurality of turbine blades which are designed for axial flow with the drive fluid (eg compressed air) , In the preferred embodiment of the invention, the drive turbine wheels extend in the axial direction together over a certain drive length and are arranged in a turbine housing with a certain outer diameter, wherein the ratio between the outer diameter of the turbine housing on the one hand and the drive length on the other hand preferably greater than 0.4 0.6 and / or less than 0.78-1. However, the invention is not limited to the above-mentioned exemplary values with regard to the dimensioning of the turbine housing and the drive turbine, but in principle also feasible with other dimensions.

It should also be mentioned that the drive turbine wheels are preferably surrounded by stator rings with a specific maximum outer diameter, the ratio between the outer diameter of the stator rings on the one hand and the drive length on the other hand being preferably in the range of 0.4-0.5. However, with regard to the dimensioning of the stator rings and the drive length, the invention is not based on the present invention. standing confined exemplary values, but in principle also feasible with other dimensions.

In the turbine rotor according to the invention, the individual turbine blades of the drive turbine wheel have a specific

Blade height in the radial direction, wherein the blade height is measured in this sense between the radially inner blade shoulder on the one hand and the radially outer blade end. The blade height is in this case preferably in the range of 0.5-50 mm, however, the invention is basically also feasible with other values of the blade height.

In the abovementioned exemplary embodiment with a plurality of drive turbine wheels arranged axially one behind the other, the individual drive turbine wheels may have a different blade height, wherein the blade height may increase in the flow direction and / or counter to the spray direction of the rotary atomizer. It should also be mentioned that in the preferred exemplary embodiment of the invention, the turbine blades of the drive turbine wheel are designed in such a way that the drive fluid (eg compressed air) flows through the turbine blades counter to the spray direction of the rotary atomizer. The drive fluid is in this case first performed by the robot side of the drive turbine to the bell cup side of the drive turbine and then deflected by 180 °, so that the drive fluid then flows against the discharge direction through the axial turbine. However, in the context of the invention, there is also the possibility in principle that the drive fluid flows through the axial turbine in the direction of discharge of the rotary atomizer, in which case no deflection of the drive fluid is required. The above-defined blade height of the individual turbine blades of the drive turbine wheel is preferably in a certain ratio to the diameter of the turbine shaft, wherein a ratio of 0.01-2.5 or

0.015-0.5 has proved to be advantageous. However, with regard to the dimensioning of the blade height, the invention is not restricted to the abovementioned ranges of values, but in principle can also be implemented with other values of the blade height.

Moreover, in the preferred embodiment, the individual turbine blades preferably have a constant blade root diameter, which is the distance between the blade lobes and the axis of rotation. However, there is also the alternative possibility that the blade base diameter is different in the adjacent drive turbine wheels. For example, the basic blade diameter can decrease from one drive wheel to the next drive wheel in the flow direction, so that the flow cross section in the flow direction then also increases, which is desirable in terms of flow.

Further, in the preferred embodiment of the invention, a certain blending density of the power turbine wheel is provided, wherein the blasting density may be, for example, in the range of 20-60 turbine blades per power turbine wheel. The blending density of the individual drive turbine wheels may be different, wherein the blending density of the drive turbine wheels may increase from one drive turbine wheel to the next drive turbine wheel in the flow direction. Alternatively, however, it is also possible for the blending density of the drive turbine wheels to be shifted from one drive turbine wheel to the next drive turbine wheel counter to the flow direction. increases. In addition, there is also the possibility that the different drive turbine wheels of the axial turbine have the same blading density. In the preferred embodiment of the invention, the drive turbine wheel is formed as a one-piece or multi-piece ring which is detachably mounted on the turbine shaft. For example, the drive turbine wheel designed as a ring can be clamped on the turbine shaft, in particular by a press fit or by thermal shrinking.

It should also be mentioned that the turbine blades of the drive turbine wheel can be produced by an additive manufacturing process, whereby such generative

Production methods are also known under the keyword "rapid prototyping".

In addition, the axial turbine according to the invention preferably also has a brake turbine wheel in order to be able to decelerate the rotary atomizer as quickly as possible, which is known per se from the prior art. For this purpose, the brake turbine wheel according to the invention has a plurality of turbine blades which, during operation, can be flowed in by a brake fluid (for example compressed air) in order to decelerate the turbine rotor. The individual turbine blades of the brake turbine wheel are preferably designed for radial flow with the brake fluid (e.g., pressurized air), as is the case with conventional brake turbine wheels. For example, the Bremsturbinenrad therefore be designed as a Pelton turbine wheel.

The Bremsturbinenrad can be arranged in this case in the axial direction between two bearing points of the turbine shaft. It However, alternatively, there is also the possibility that the Bremsturbinenrad is arranged in the axial direction outside of the two bearing points of the turbine shaft. It should also be mentioned that the brake turbine wheel preferably has a substantially larger diameter than the drive turbine wheel. This is desirable so that a sufficiently large braking torque can be generated. With regard to the blade profile of the individual turbine blades of the drive turbine wheel or of the brake turbine wheel, there are many possibilities within the scope of the invention. For example, the turbine blades may have a symmetric or semi-symmetrical profile, an S-beam profile, or a beam profile, to name just a few examples.

However, in the preferred embodiment of the invention, the turbine blades have a certain preferred geometry. Thus, the individual turbine blades preferably have an entry angle in the range of 65-75 °, whereas in the prior art an entry angle of approximately 60 ° is usual. By contrast, the outlet angle of the turbine blades preferably corresponds to the entry angle with a tolerance range of ± 10 ° or even ± 5 °. The outlet angle of the turbine blades, however, is preferably in the range of 55 ° -75 °. This results in the preferred embodiment, the result that the sum of the inlet angle and the outlet angle is preferably in the range of 110 ° -145 °. It should also be mentioned that the turbine rotor according to the invention has a certain specific speed n _s , which is calculated according to the following formula: ω · V ⁰ · ⁵ with:

V: volumetric flow at inlet [m ³ / s]

e: Specific work [J / kg]

ω: rotational speed [rad / s].

It should be noted that the specific speed n _{s is} preferably in the range of 0.1-0.3, whereas the specific speed in conventional axial turbines is usually in the range of 0.5-1.

In the turbine rotor according to the invention, the turbine shaft has a plurality of bearings to rotatably support the turbine shaft, wherein the bearings can be particularly hardened, for example. The drive turbine wheel is in this case preferably in the axial direction between the two bearing points. This advantageously allows a large axial distance between the bearing points, which in turn advantageously leads to a greatly increased tilting rigidity. In the case of handling the rotary atomizer by means of a painting robot, this enables significantly higher robot acceleration values and thus also higher painting speeds for non-linear painting paths. The bearing points of the turbine shaft in this case have a certain bearing length in the axial direction, while the turbine shaft has a certain shaft diameter. In the turbine rotor according to the invention, the bearing length is preferably in a certain ratio to the shaft diameter, wherein this ratio is preferably in the range of 0.8-1.2, wherein a value of 1 has proven to be particularly advantageous. However, the invention can in principle also be realized with other values. It should also be mentioned that the turbine shaft is preferably hollow, which is known per se from the prior art. Preferably, however, the shaft inner diameter of the hollow turbine shaft is so large that the turbine shaft a

Paint tube with at least two main needles and record at least two returns, whereas conventional rotary atomizer usually have only a single main needle and a single main needle valve. On the other hand, the rotary atomizer according to the invention with at least two main needle valves allows very little color change times and losses since it is possible to paint over one main needle valve while the next color is already pressed against the second main needle valve. In a color change then only the line area must be flushed downstream of the previously used main needle valve. For a simple application, however, one can also imagine a color tube with a smaller diameter, i. the existing space is not used.

In addition, there is also the possibility that the shaft inner diameter of the hollow turbine shaft is so large that the hollow turbine shaft can accommodate two mixing elements for two-component material (e.g., stock paint and hardener).

The shaft inner diameter of the turbine shaft is therefore preferably in the range of 20-40 mm.

It should also be noted that the turbine shaft in the axial direction is preferably shorter than 15 cm, 14 cm or 13 cm, wherein the bearing points preferably have an axial distance of more than 3 cm, 6 cm or 10 cm. The invention thus claims protection for the above-described turbine rotor according to the invention as a single component. In addition, however, the invention also claims protection for a complete drive turbine for a rotary atomizer with such a turbine rotor. Furthermore, protection is also claimed for a rotary atomizer with an axial turbine according to the invention and for a painting robot with a rotary atomizer, which in contrast to the prior art contains an axial turbine.

The drive turbine according to the invention is preferably characterized by a certain specific mechanical drive power, wherein the specific drive power is preferably 0.6 Wmin / Nl, 0.7 Wmin / Nl, 0.8 Wmin / Nl or even 0.9 Wmin / nl. The specific mechanical drive power in this sense is the ratio between the mechanical drive power of the drive turbine on the one hand and the volume flow of the input drive fluid (for example compressed air) on the other.

In addition, the drive turbine according to the invention can be characterized by a specific mechanical drive power, which is preferably in the range of 0.7 W / g-1.5 W / g. The specific mechanical drive power in this sense is the ratio between the mechanical drive power of the drive turbine on the one hand and the mass of the drive turbine on the other.

Further, the specific mechanical drive power is preferably in the range of 1.5 W / cm ³ -10 W / cm ³ , wherein the specific mechanical drive power in this sense, the ratio between the mechanical drive power on the one hand and the space of the drive turbine on the other hand. The inventive use of an axial turbine allows thus advantageously a larger power density than conventional radial turbines.

The inventive principle of an axial turbine for driving a rotary atomizer allows a drive power of more than 1000 W or even more than 1400 W.

Moreover, a thermal efficiency of more than 50%, 60% or even more than 70% can be realized, in particular at a speed of between 40000 rpm and 60,000 rpm and with a volume flow of the drive fluid (e.g.

Compressed air) between 800 Nl / min and 1200 Nl / min.

It should also be mentioned that the specific mechanical drive power can be greater than 0.1 W / mbar, 0.2 W / mbar, 0.3 W / mbar or even greater than 0.4 W / mbar, the specific Drive power in this sense is the ratio between the mechanical drive power on the one hand and the pressure difference between the inlet and outlet on the other.

It has already been mentioned above that the driving fluid (for example, compressed air) flows through the axial turbine preferably counter to the spraying direction, but the driving fluid is supplied from the robot side. This leadership of

Drive fluid makes a deflection of the drive fluid required, for which purpose preferably a deflection ring is provided. In the preferred embodiment of the invention. However, the deflection of the drive fluid is only partially in the deflection ring. Thus, the drive fluid preferably enters the deflection ring at right angles to the rotational axis of the rotary atomizer and then exits the deflection ring against the direction of discharge of the rotary atomizer in order to flow against the drive turbine wheel. The deflection ring thus causes only a deflection by a deflection angle of about 90 °. The remaining 90 ° of the total required deflection angle of 180 ° can then be realized outside the drive turbine. However, it is within the scope of the invention also possible that the deflection realized the entire required deflection angle of 180 °.

In addition, in the preferred exemplary embodiment of the invention, the deflection ring also has a further function in that the deflection ring distributes the drive fluid uniformly over the entire annular flow cross section of the axial turbine, thereby achieving a uniform flow.

Furthermore, there is the possibility that in the deflection ring, a stator is integrated, which may for example be integrally formed on the deflection ring.

Furthermore, the deflecting ring can also form a seal or contain a separate seal to seal an annular gap between the deflecting ring and the turbine shaft towards the bell cup.

In addition to the turbine rotor described above in detail, the drive turbine according to the invention preferably has a turbine housing and at least one shaping air line for supplying a shaping air ring, wherein the shaping air line is preferably led at least partially through the turbine housing.

In addition, the drive turbine according to the invention preferably also has a bearing unit in which the turbine rotor is rotatably mounted. A special feature of the drive turbine according to the invention in the preferred embodiment is that a color tube for supplying the coating agent to be applied by the hollow turbine protrudes nenwelle and is attached to the bearing unit, in particular by a screw. In contrast to the conventional rotary atomizers, the bearing unit can therefore be bolted directly to the paint tube to form a unit. This makes it possible, with appropriate tolerances and an end face introduced during assembly between the color tube and turbine shaft centering that concentricity and plan support are much better ensured, so that no relative movement between the bearing unit and the paint tube takes place.

Furthermore, the drive turbine according to the invention preferably comprises an intermediate sleeve which encloses a radial bearing, the deflection ring and / or parts of the turbine rotor. The intermediate sleeve is preferably made of a mechanically strong material, such as aluminum, steel or an alloy, whereas the surrounding housing may consist of a mechanically less resilient material, such as plastic. In this case, the intermediate sleeve preferably also has the task of feeding the deflecting ring already explained in detail above with the drive fluid, wherein part of the required deflection of the drive fluid can also take place within the intermediate sleeve. Furthermore, in the preferred embodiment, the drive turbine according to the invention preferably has at least one stator ring with a plurality of guide vanes, wherein the stator ring surrounds the turbine shaft in an annular manner and is arranged in a stationary manner.

The drive turbine according to the invention preferably has a novel bearing flange to connect the drive turbine mechanically and fluidically with a rotary atomizer, in which the drive turbine is installed and in the mounted state is driven by the drive turbine. The novel bearing flange according to the invention differs from conventional bearing flanges of known drive turbines in that the various connections are distributed over two connection levels, wherein the two connection levels are axially spaced from one another. In this case, the first connection plane is preferably arranged proximally, ie on the robot or machine side. On the other hand, the second connection plane is preferably arranged distally, ie on the side of the bellcup. The first connection level preferably contains all supply air connections for air feeds, in particular for shaping air, drive air, storage air and brake air. The second connection level of the bearing flange, on the other hand, contains all exhaust air connections for air recirculation.

In this case, the first connection plane is preferably designed substantially in the form of a ring, wherein the supply air connections are arranged distributed in the end face of the ring over the ring. The exhaust ports in the second connection plane are then preferably arranged substantially centrally within the ring of the first connection plane.

In addition, the second connection plane of the bearing flange preferably has a keyway for receiving a passpipe mounted on the color tube side for preventing rotation and centering a color tube.

Furthermore, the second connection plane of the bearing flange may have at least one thread set for fastening a color tube.

In addition, there is the possibility that the second connecting plane of the bearing flange has a substantially planar contact surface on its distal side. Furthermore, the bearing flange preferably contains at least one through-hole for the passage of an optical waveguide for speed detection of the drive turbine, wherein the through-hole for the optical waveguide is preferably arranged in the second connection plane.

In addition, it should be mentioned that the exhaust air connection for brake air and / or bearing air is preferably offset radially outwards relative to the other exhaust air connections (for example for engine drive air and steering air).

It should also be mentioned that the exhaust air connection for the drive air preferably has a substantially larger cross section than the other exhaust air connections.

In addition, the first connection plane of the bearing flange can have an axially aligned dowel pin and / or an axially aligned receiving bore for such a dowel pin in order to position the drive turbine.

Furthermore, the novel bearing flange according to the invention preferably also differs by the seal of the terminals. Thus, axial seals (eg O-rings) are preferably used instead of the conventionally used radially sealing O-rings in the bearing flange according to the invention. As a result, larger channel cross sections can be realized. Another advantage is that in the conventionally used radially sealing O-rings pressed nipples are required, the elimination thus increases the mounting comfort in the bearing flange according to the invention. In addition, it should also be mentioned that the rotary atomiser according to the invention preferably carries a bell cup with a specific diameter in the range of 30-80 mm, the outside diameter of the turbine or bell-plate shaft being in the range of 24-28 mm. In the context of the invention, therefore, a particularly advantageous ratio between the diameter of the bell cup, on the one hand, and the shaft diameter, on the other hand, is desired, this ratio preferably being in the range of 1.07-3.33.

Finally, it should be noted that the invention also claims protection for the above individual components (for example, intermediate sleeve, bearing unit, stator ring, deflection ring, bearing flange, etc.), irrespective of the other technical features and components.

Other advantageous developments of the invention are characterized in the subclaims or are explained in more detail below together with the description of the preferred embodiments of the invention with reference to FIGS. FIG. 3 is an exploded view of an inventive device. FIG. 3 is an exploded view of an axial turbine according to the invention for driving a rotary atomizer, a schematic perspective view to illustrate the mounting of several rotor rings of the axial turbine on the turbine shaft

Embodiment of an axial turbine for driving a rotary atomizer, FIG. 4 shows a sectional view of the front region of the drive turbine according to FIG. 3,

5 shows a cutaway perspective view of the turbine housing of the drive turbine from FIGS. 3 and

6 shows a cutaway perspective view of the intermediate sleeve of the drive turbine according to FIGS. 4 and 5, wherein a radial bearing and a deflection ring are already mounted in the intermediate sleeve,

7 shows a cutaway perspective view of the drive turbine itself, the drive turbine comprising a plurality of stator rings and a plurality of rotor rings, FIG.

8 shows a cutaway perspective view of a radial-axial bearing of the drive turbine from FIGS. 3 to 7, FIG.

9 shows a cutaway perspective view of the turbine shaft of the drive turbine with a brake from FIGS. 3 to 8, FIG. 10 shows a schematic representation of the blade geometry of the turbine blades,

11 shows a side view of a rotary atomizer according to the invention with the drive turbine according to FIGS. 3 to 9, FIG.

Figure 12A is an end view of the bearing flange of the ^' power turbine with numerous connections, and Figure 12B is a slightly perspective view of the bearing flange of the drive turbine.

1 shows a schematic representation of a drive turbine 1 according to the invention for driving a turbine shaft 2, which carries a conventional bell cup 3 in operation at its distal end 2.

In contrast to conventional radial turbines, the drive turbine 1 is designed as an axial turbine. This means that the drive air flows through the axial turbine in the axial direction.

For this purpose, the drive turbine 1 a plurality of rotor rings 4, 5, 6, which may be shrunk onto the outer surface of the turbine shaft 2, as will be described in detail with reference to Figure 2.

In addition, the drive turbine 1 has a plurality of stator rings 7, 8 which are each arranged between two of the adjacent rotor rings 4-6.

In this case, the drive air is supplied on the robot side and flows in the axial direction initially outside the drive turbine 1 as far as a deflection ring 9 which deflects the drive air by 180 ° and introduces it into the first rotor ring 4.

It should also be mentioned that the annular flow cross-section of the drive turbine 1 increases in the flow direction (ie from left to right in the drawing). Furthermore, it can be seen that the blade base diameter of the rotor rings 4, 5, 6 is constant, whereas the blade height of the rotor rings 4, 5, 6 is different, in order to the in Strö- direction of flow to realize increasing flow area.

From the likewise schematic representation in Figure 2 it can be seen that the rotor rings 5, 6 simply in axial

Direction to the turbine shaft 2 can be pushed to mount the rotor rings 5, 6 on the turbine shaft 2. The assembled rotor rings 5, 6 can then be fixed on the turbine shaft 2, for example by a press fit or by thermal shrinkage.

A preferred exemplary embodiment of a drive turbine 10 according to the invention will now be described below with reference to FIGS. 3 to 9, wherein the drive turbine 10 comprises a turbine housing 11, an intermediate sleeve 12 with a radial bearing 13 and a deflection ring 14, a turbine unit 15 with stator and rotor rings, a radial-axial bearing 16, a turbine shaft 17 with a molded Bremsturbinenrad 18, a spacer ring 19 and a bearing flange 20 has.

In the following, the structure and the function of the turbine housing 11 will now be described with reference to the perspective views in Figures 4 and 5 first. First, it should be mentioned that the turbine housing 11 has on its front side a directing air ring with a plurality of shaping air nozzles, via the shaping air nozzles 21, a shaping air jet can be discharged to form the emitted from the bell cup spray jet of the coating agent, which in itself from the prior Technique is known.

In this exemplary embodiment, the turbine housing 11 consists of a mechanically load-bearing material (eg an aluminum alloy). Umlegierung) and is partially surrounded by a cover 11 ', which consists of plastic.

In the turbine housing 11, an electrical through-connection 22 is located in the front region, which cooperates with a correspondingly adapted through-connection 23 in the intermediate sleeve 12 (see FIG. 6) and enables electrical contacting. In the following, the function and the construction of the intermediate sleeve 12 will now be described with reference to the perspective views in Figures 4 and 6.

In the front region, the intermediate sleeve 12 carries the radial roller 13 for supporting the turbine shaft 17.

Behind it in the axial direction is the ümlenkring 14, which has the task of deflecting the radially entering the deflection ring 14 drive air at right angles to the rear, so that the drive air enters the axially located behind the deflection ring 14 turbine unit 15, wherein the turbine unit 15 in FIG not shown.

However, it can be seen from FIGS. 4 and 6 that the intermediate sleeve 12 has a plurality of radial bores 24 distributed over the circumference, into which correspondingly adapted grub screws can be screwed in order to fix the turbine unit 15 in the axial direction, as can be seen in particular from FIG is.

The construction and operation of the turbine unit 15 will now be described with reference to FIGS. 4 and 7. Thus, the turbine unit 15 in this embodiment consists of a plurality of rotor rings 25, 26, 27, the on arranged the turbine shaft 17 and are connected against rotation with the turbine shaft 17.

The rotor rings 25, 27 are surrounded by a plurality of stator rings 28, 29, wherein the stator rings 28, 29 are fixedly mounted and do not rotate during operation.

From FIG. 7, it can further be seen that the turbine unit 15 has an annular flow cross-section which widens in the flow direction with an expansion angle α, so that the through-flow cross-section of the downstream rotor ring 27 is greater than that

Flow cross-section of the upstream rotor ring 25. This is aerodynamically useful because the drive air relaxes when flowing through the turbine unit from one stage to the next stage. The expansion angle α can for example be in the range of 5 ° -10 ° and is determined by fluidic considerations. The operation and construction of the turbine shaft 17 will now be described with reference to FIGS. 4 and 9.

At its distal end, the turbine shaft 17 has, both inside and outside, an annular groove 30, 31 which is intended for

Assembly of a bell plate is used. Alternatively, however, there is also the possibility that the turbine shaft 17 carries at its distal end an internal thread on which the bell cup can be screwed.

In addition, the turbine shaft 17 has two bearing points 32, 33, on which the turbine shaft is mounted in the radial bearing 13 and in the radial-axial bearing 16. Finally, the turbine shaft 17 still has the molded-on brake turbine wheel 18 in order to be able to brake the turbine shaft 17 as quickly as possible with the bell plate mounted thereon. The Bremsturbinenrad 18 is in this case formed as a Pelton turbine wheel and therefore has numerous turbine ^¬ nenschaufeln, which are designed for a radial flow with drive air, as it is known per se from the prior art. It should be noted that the Bremsturbinenrad 18 in the axial direction outside of the two bearings 32, 33 is arranged ^¬ . In contrast, the turbine unit 15 of the drive turbine 10 is in the mounted state axially between the two bearings 32, 33rd

Furthermore, FIG. 10 shows a schematic illustration of a turbine blade 34 with a front edge 35 and a trailing edge 36. The front edge 35 of the turbine blade 34 is angled in this direction to an axial direction 37 shown schematically by an entry angle _IN approximately equal to 70 °. In addition, the trailing edge 36 of the turbine blade 34 is angled at an outlet angle α ₀ υτ relative to the axial direction 37, wherein the _{inlet angle ΪΝ is} approximately equal to the outlet angle α ₀ οτ.

Finally, FIG. 11 shows a rotary atomizer 38 according to the invention with the drive turbine 10 shown schematically, which drives a bell cup 39. In addition, in this drawing, a valve unit 40 is shown schematically. Finally, the drawing also shows an electrode ring 41 for external charging of sprayed from the bell cup 39 coating agent. The structure and mode of operation of the bearing flange 20, which is already shown in perspective in FIG. 3, will now be described below with reference to FIGS. 12A and 12B. It is noteworthy here that the bearing flange 20 has two connection levels El, E2, which are axially spaced, as can be seen from Figure 3.

The first connection level El contains all supply air connections LL1-LL3, ML1-ML2, BR1 and LL1, namely for steering air, engine air or drive air, engine bearing air and brake air.

By contrast, the second connection level E2 contains all exhaust air connections AL_MLL1, AL_ML, AL_BR1.

It should also be mentioned that the first connection plane E1 is formed proximally in the form of a ring, the different supply air connections LL1-LL3, ML1-ML2, BR1 and MLL1 being arranged in the end face of the ring.

In contrast, in the distally arranged second connection plane E2, the exhaust air connections AL_MLL1, AL_ML, AL_BR1 are arranged substantially centrally within the ring of the first connection plane E1.

Furthermore, the bearing flange 20 also comprises threaded inserts GWE_T for the turbine, threaded inserts GWE_FR for a color tube, a hole LWL for an optical waveguide for rotary Numeric detection and a feather key PF and a centering pin ZS.

It is also important that the various supply air connections LL1-LL3, ML1-ML2, BR1 and MLL1 and the exhaust connections AL_MLL1, AL_ML, AL_BR1 are not sealed by radial sealing O-rings, unlike conventional drive turbine flanges by axially (flat) sealing O-rings. This offers the advantage that larger channel cross sections can be realized. In addition, the ease of assembly is increased by eliminating the nipples otherwise required for radially sealing O-rings. The invention is not limited to the preferred embodiments described above. Rather, a variety of variants and modifications is possible, which also make use of the inventive idea and therefore fall within the scope. In particular, the invention also claims protection for the subject-matter of the sub-claims, independently of the subject-matter of the claims referred to above.

Reference sign list

1 drive turbine

2 turbine shaft

3 bell plates

4 rotor ring

5 rotor ring

6 rotor ring

7 stator ring

8 stator ring

9 deflection ring

10 drive turbine

11 turbine housing

11 'cover

12 intermediate sleeve

13 radial bearings

14 deflection ring

15 turbine unit

16 radial-axial bearings

17 turbine shaft

18 brake turbine wheel

19 spacer ring

20 bearing flange

21 shaping air nozzles

22 via

23 via

24 radial bore

25 rotor ring

26 rotor ring

27 rotor ring

28 stator ring

29 stator ring

30 ring groove

31 ring groove 32 storage location

33 storage location

34 turbine blade

35 leading edge of the turbine blade

36 trailing edge of the turbine blade

37 axial direction

38 rotary atomizer

39 bell plates

40 valve unit

41 electrode ring

Expansion angle of the flow cross-section

Inlet angle of the turbine blades

Οίουτ outlet angle of the turbine blades

LL1 supply air connection for shaping air 1

LL2 supply air connection for shaping air 2

LL3 supply air connection for shaping air 3

ML1 supply air connection for engine air 1

ML2 supply air connection for engine air 2

GWE_T threaded insert for turbine

G E_FR Threaded insert for paint tube

El First connection level

E2 Second connection level

AL MLL1 exhaust air connection for engine bearing air 1

AL_ML exhaust air connection for engine air

AL_BR1 exhaust air connection for brake air 1

BR1 supply air connection for brake air 1

MLL1 supply air connection for engine bearing air 1

L L Hole for optical fibers

PF feather key

ZS centering pin

Claims

1. Turbine rotor (17, 25, 26, 27) for a drive turbine (1, 10) of a rotary atomizer (38), with

a) a rotatably mounted turbine shaft (2, 17) with a mounting option for a bell cup (3, 39), and

b) at least one drive turbine wheel (4-6; 25-27) with a plurality of turbine blades (34), wherein the turbine blades (34) of the drive turbine wheel (4-6; 25-27) are in operation by a drive fluid to the turbine rotor ( 17, 25, 26, 27), characterized

c) that the drive turbine wheel (4-6, 25-27) for axial flow of the turbine blades (34) with the

Drive fluid is designed.

2. turbine rotor (17, 25, 26, 27) according to claim 1,

characterized.,

a) that axially in succession more drive turbine wheels

(4-6, 25-27) are arranged, wherein the individual drive turbine wheels (4-6, 25-27) each have a plurality of turbine blades (34) which are designed for axial flow with the drive fluid, and / or b in that the drive turbine wheels (4-6; 25-27) extend together in the axial direction over a certain drive length and are arranged in a turbine housing (11) with a certain outer diameter, the ratio between the outer diameter of the turbine housing (11) and the drive length is greater than 0.4, 0.5, 0.6 or 0.625 and / or less than 1, 0.9, 0.8 or 0.780, and / or c) that the drive turbine wheels (4-6, 25-27) extend together in the axial direction over a certain drive length and are surrounded by stator rings (7, 8, 28, 29) with a certain maximum outside diameter, the ratio between the outer diameter of the stator rings (7, 8; 28, 29) and the drive length is greater than 0.4 and / or less than 0.5.

3. turbine rotor (17, 25, 26, 27) according to one of the preceding claims, characterized

a) that the turbine blades (34) of the drive turbine wheel (4-6; 25-27) have a specific blade height in the radial ^direction between a radially inner blade shoulder and a radially outer blade end,

b) that the blade height is greater than 0.5mm, 1mm, 2mm,

5mm and / or smaller than 60mm, 50mm, 25mm, 20mm, 15mm, 10mm, and / or

c) the drive turbine wheels (4-6; 25-27) have different blade heights, wherein the blade height increases in the flow direction and / or counter to the spray direction of the rotary atomizer (38), and / or

d) that the turbine blades (34) of the drive turbine wheel (4-6; 25-27) are adapted to the

Drive fluid, the turbine blades (34) against the spray direction of the rotary atomizer (38) flows, or

e) that the turbine blades (34) of the drive turbine wheel (4-6; 25-27) are adapted to the

Drive fluid, the turbine blades (34) in the discharge direction of the rotary atomizer (38) flows.

4. turbine rotor (17, 25, 26, 27) according to one of the preceding claims, characterized by

a) a certain ratio between the blade height of the drive turbine wheel (4-6; 25-27) on the one hand and the diameter of the turbine shaft (2; 17) on the other hand, wherein the ratio is greater than 0.01, 0.012 or 0.015 and / or less than 3 , 2.5, 2, 1.5, 1 or 0.5, and / or

b) a certain blade base diameter, wherein the

Blade ground diameter is constant, and / or

c) a certain blending density of the drive turbine wheel (4-6; 25-27), wherein the blasting density is greater than 15, 17 or 19 turbine blades (34) per drive turbine wheel (4-6; 25-27) and / or less than 80, 70 or 60 turbine blades (34) per drive turbine wheel (4-6; 25-27), and / or

d) that the drive turbine wheels (4-6; 25-27) have different blading densities, and / or e) that the blading density of the drive turbine wheels

(4-6, 25-27) increases from one drive turbine wheel (4-6; 25-27) to the next drive turbine wheel (4-6; 25-27) in the flow direction, or

f) that the blading density of the drive turbine wheels

(4-6; 25-27) increases from one power turbine wheel (4-6; 25-27) to the next power turbine wheel (4-6; 25-27) counter to the flow direction.

5. turbine rotor (17, 25, 26, 27) according to one of the preceding claims, characterized in that

a) that the drive turbine wheel (4-6; 25-27) is formed as a one-piece or multi-part ring, which is detachably arranged on the turbine shaft (2; 17), and / or b) that the ring is clamped on the turbine shaft (2; 17), in particular by a press fit or by shrinking, and / or

c) that the turbine blades (34) of the drive turbine wheel (4-6; 25-27) are produced by an additive manufacturing process, and / or

d) that the drive turbine wheel (4-6; 25-27) and the turbine shaft (2; 17) are integrally formed, in particular by machining a blank of the turbine shaft (2; 17).

6. turbine rotor (17, 25, 26, 27) according to claim one of the preceding claims, characterized in that

a) that a Bremsturbinenrad (18) with a plurality of turbine blades (34) is provided, wherein the turbine blades (34) of the Bremsturbinenrades (18) can be flowed during operation of a brake fluid to decelerate the turbine rotor, and / or

b) that the Bremsturbinenrad (18) is designed for a radial Beströ- tion with the brake fluid, and / or

c) that the Bremsturbinenrad (18) is a Pelton turbine wheel, and / or

d) that the Bremsturbinenrad (18) in the axial direction between two bearing points (32, 33) or outside of the La- places (32, 33) is arranged, and / or

e) that the Bremsturbinenrad (18) has a substantially larger diameter than the Antriebsturbinenrad (4-6, 25-27).

7. Turbine rotor (17, 25, 26, 27). according to one of the preceding claims, characterized in that the turbine blades (34) of the Antriebsturbinenrads and / or the Bremsturbinenrades (18) respectively

a) a symmetrical profile, b) a semi-symmetrical profile,

c) an S-beating profile or

d) have a club profile.

8. turbine rotor (17, 25, 26, 27) according to one of the preceding claims, characterized in that

a) that the turbine blades (34) of the drive turbine wheel and / or the Bremsturbinenrades (18) each have a front edge (35) which are aligned with a certain inlet angle (cti _N ) relative to the axis of rotation (37) of the turbine rotor, and / or

b) that the turbine blades (34) of the Antriebsturbradrads and / or the Bremsturbinenrades (18) each have a trailing edge (36) which is aligned with a certain _{outlet angle} (α _0ϋ τ) relative to the axis of rotation (37) of the turbine rotor, and / or

c) that the sum of the _{inlet angle} (α _ίΝ ) and the _{outlet angle} (α _ουτ ) is greater than 90 °, 100 ° or 110 ° and / or less than 160 °, 150 ° or 145 °, and / or

d) that the outlet angle (α ₀ υτ) with a tolerance range of ± 10 ° or ± 5 ° corresponds to the inlet angle (cc _IN ), and / or

e) that the outlet angle (α _ου τ) is greater than 55 °, 60 ° or 65 ° and / or less than 85 °, 80 ° or 75 °.

9. turbine rotor (17, 25, 26, 27) according to one of the preceding claims, characterized in that

a) that the turbine rotor has a certain specific speed n _s , which is calculated according to the following formula: co ^■ V ⁰ ' ⁵

n _s =

e0,75

With V: volumetric flow at inlet [m ³ / s]

e: Specific work [J / kg]

ω: rotation speed [rad / s], and

b) that the specific speed n _{s is} less than 0.4 or 0.3 and / or greater than 0.07 or 0.1.

10. turbine rotor (17, 25, 26, 27) according to claim one of the preceding claims, characterized in that

a) that the turbine shaft (2; 17) several bearings

(32, 33) for rotatably supporting the turbine shaft (2; 17) in each case a bearing, and

b) that the drive turbine wheel (4-6, 25-27) in axial

Direction between the two bearing points (32, 33) is arranged.

11. Turbine rotor (17, 25, 26, 27) according to one of the preceding claims, characterized in that

a) that the bearing points (32, 33) of the turbine shaft (2;

17) each have a certain bearing length in the axial direction, and

b) that the turbine shaft (2; 17) has a certain shaft diameter, and

c) that the bearing length has a certain ratio to the shaft diameter, and

d) that the ratio is greater than 0.6, 0.7 or 0.8 and / or less than 1.4, 1.3 or 1.2.

12. Turbine rotor (17, 25, 26, 27) according to one of vorherge existing claims, characterized

a) that the turbine shaft (2; 17) is hollow and has an internal shaft diameter sufficient to accommodate a paint tube with two main needles and two returns, and / or b) that the turbine shaft (2; 17) is hollow and has an internal shaft diameter sufficient to accommodate two mixing elements for two-component material, and / or

c) that the turbine shaft (2; 17) is hollow and has an internal shaft diameter of more than 18mm, 19mm or 20mm and / or less than 22mm, 21mm or 20mm.

13. turbine rotor (17, 25, 26, 27) according to one of claims 9 to 12, characterized in that

a) that the bearing points (32, 33) have an axial distance of more than 3cm, 6cm or 10cm, and / or b) that the turbine shaft (2; 17) in the axial direction is shorter than 15cm, 14cm or 13cm.

14. Drive turbine (1, 10) for a rotary atomizer (38) with a turbine rotor (17, 25, 26, 27) according to one of the preceding claims.

15. Drive turbine (1; 10) according to claim 14,

marked by

a) a specific specific mechanical drive power as a ratio between the mechanical drive power on the one hand and the volume flow of the supplied drive fluid on the other hand, the specific drive power is greater than 0.6 Wmin / Nl, 0.7 Wmin / Nl, 0.8 Wmin / Nl or 0.9 Wmin / Nl, and / or

b) a specific specific mechanical drive power as the ratio between the mechanical drive power on the one hand and the mass of the drive turbine (1;

10) on the other hand, wherein the ratio is greater than 0.7W / g, 0.8W / g, 0.9W / g or lW / g and / or less than 2W / g, l, 7W / g, l, 6W / g, or 1, 5W / g, and / or c) a certain specific mechanical drive power as a ratio between the mechanical drive power on the one hand and the installation space of the drive turbine (1, 10) on the other hand, wherein the ratio is greater l, 5W / cm ³ , 2W / cm or l, 5 / cm and / or less than

10W / cm ³ , 6W / cm ³ , 4.5W / cm ³ , and / or

d) a mechanical drive power of more than 1000W,

1200W, 1300W or 1400, and / or less than 100kW, 50kW, 25kW, 10kW, 5kW or 2kW, and / or

e) a thermal efficiency of more than 50%, 60% or 70%, in particular at a speed between 40000min ^"1 and 60000min ^{" 1} and a flow rate of the drive fluid between 800Nl / min and 1200Nl / min, and / or

f) a specific mechanical drive power of more than 0.1, 0.2 0.3 or 0.4 W / mbar as the ratio between the mechanical drive power on the one hand and the pressure difference between the inlet and outlet on the other.

16. Drive turbine (1, 10) according to one of claims 14 to 15, characterized

a) that the drive turbine (1, 10) has a deflection ring (9;

14) to redirect the drive fluid, wherein the drive fluid transversely, in particular at right angles, to

The spray direction of the rotary atomizer (38) enters the deflecting ring (9; 14) and exits the deflecting ring (9; 14) counter to the spraying direction of the rotary atomizer (38) to flow into the driving turbine wheel (4-6; 25-27); or

b) that the drive turbine wheel (4-6; 25-27) has an annular flow cross section and the deflection ring (9; 14) distributes the drive fluid uniformly over the entire flow cross section, and / or c) that the deflecting ring (9; 14) has an integrated and / or integrally molded stator, and / or d) that the deflecting ring (9; 14) forms a seal or contains a separate seal to form an annular gap between the deflecting ring (9 14) and the turbine shaft (2; 17) to the bell cup (3; 39) to seal.

17. Drive turbine (1; 10) according to one of claims 14 to

16, characterized by

a) a turbine housing (11) and

b) at least one shaping air line for supplying a shaping air ring with shaping air for shaping the spray jet emitted by the rotary atomizer (38), the shaping air line being guided at least partially through the turbine housing (11).

18. Drive turbine (1, 10) according to one of claims 14 to

17, characterized by

a) a bearing unit for rotatably supporting the turbine rotor and

b) a color tube for supplying the coating agent to be applied, wherein the color tube protrudes through the hollow turbine shaft (2, 17) and is fastened to the bearing unit, in particular by a screw connection, and / or

c) an adjustable centering device for centering the color tube in the hollow turbine shaft (2; 17).

19. Drive turbine (1, 10) according to one of claims 14 to

18, characterized by an intermediate sleeve (12) for receiving a radial bearing (13) and / or the deflecting ring (9; 14) and / or a part of the turbine rotor.

20. Drive turbine (1; 10) according to claim 19,

characterized,

a) that a turbine housing (11) is provided, wherein the turbine housing (11) consists of plastic, while the intermediate sleeve (12) made of metal, in particular aluminum, and / or

b) that the intermediate sleeve (12) feeds the deflection ring (9, 14) with the drive fluid, and / or

c) that the intermediate sleeve (12) deflects the drive fluid, wherein the drive fluid in the discharge direction in the

Intermediate sleeve (12) enters and transversely, in particular at right angles, emerges from the intermediate sleeve (12) inwards towards the direction of discharge and passes into the deflecting ring (9, 14).

21. Drive turbine (1, 10) according to one of claims 14 to

20, characterized by at least one stator ring (7, 8, 28, 29) with a plurality of guide vanes, wherein the stator ring (7, 8, 28, 29) surrounds the turbine shaft (2, 17) in an annular manner and is arranged stationary.

22. Drive turbine (1, 10) according to one of claims 14 to

21, characterized

a) that the drive turbine (1, 10) has a bearing flange

(20) for mechanically and fluidically connecting the drive turbine (1; 10) to a rotary atomizer (38) into which the drive turbine (1; 10) is installed, and / or

b) that the bearing flange (20) on the connection side has a first connection plane (El) and a second connection plane (E2), and / or

c) that the first connection plane (El) of the bearing flange

(20) axially from the second connection plane (E2)

is spaced, and / or d) that the first connection plane (El) of the bearing flange (20) is arranged proximally and the second connection plane (E2) is arranged distally, and / or

e) that the first connection level (El) of the bearing flange

(20) all supply air connections (LL1-LL3, ML1-ML2, BR1,

MLL1) for air feeds, in particular for shaping air, drive air, internal clearance and brake air, and / or

f) that the second connection plane (E2) of the bearing flange

(20) contains all return air connections (AL_LL1, AL_ML, AL_BR1) for air returns, and / or

g) that the first connection plane (El) of the bearing flange

(20) is formed substantially in the form of a ring, wherein the supply air terminals (LL1-LL3, ML1-ML2, BR1, MLLL) are arranged distributed in the end face of the ring over the ring, and / or

h) that the exhaust air connections (AL_MLL1, AL_ML, AL_BR1) in the second connection plane (E2) are arranged substantially centrally within the ring of the first connection plane (El), and / or

i) that the second connection plane (E2) of the bearing flange

(20) has a keyway for receiving a color tube side mounted key (PF) for preventing rotation and centering of a color tube, and / or j) that the second connection plane (E2) of the bearing flange

(20) has at least one threaded insert (GWE_T, GWE_FR) for fixing a color tube, and / or k) that the second connection plane (E2) of the bearing flange

(20) has on its distal side a substantially planar support surface, and / or

1) that the bearing flange (20) has at least one through-hole (LWL), in particular in the second connection plane, for carrying out an optical waveguide for speed detection of the drive turbine, and / or m) that the exhaust air connection (AL_MLL1, AL_BR1) for brake air and / or bearing air are offset radially outwards relative to the other exhaust air connections (AL_ML), and / or

n) that the exhaust air connection (AL_ML) for drive air has a substantially larger cross section than the other exhaust connections (AL_MLL1, AL_BR1), and / or o) that the first connection level (El) of the bearing flange

(20) has an axially aligned dowel pin and / or an axially aligned receiving bore for a dowel pin to position the drive turbine, and / or

p) that the supply air connections (LL1-LL3, L1-ML2, BR1,

MLL1) and / or the exhaust ports (AL_MLL1, AL_ML, AL_BR1) are sealed by an axial seal.

23. Intermediate sleeve (12), bearing unit, drive turbine wheel (4-6, 25-27), deflection ring (9, 14), stator ring (7, 8, 28, 29) or bearing flange (20) according to one of the preceding claims 19 or 20 as a single component.

24. Rotary atomiser (38) with a drive turbine (1, 10) according to one of claims 14 to 21.

25. Use of an axial turbine for driving a rotary atomizer (38).