EP3088090B1 - Varnishing device and method of coating an external surface of a varnishing object - Google Patents

Description

The invention relates to a painting device for painting an outer surface of a Lackierobjekts, with an output device for providing a continuous or discontinuous paint stream and with a receiving device for receiving and positioning a Lackierobjekts opposite to the output device, wherein the output device has a dispensing nozzle and a fluidically communicating connected to the dispensing nozzle paint conveyor includes, which is designed for a pressurized delivery of paint to the dispensing nozzle. Furthermore, the invention relates to a method for painting an outer surface of a Lackierobjekts.

From the WO 02/20174 A1 discloses an apparatus for holding a substrate that includes a rotating member that is rotatable about a first axis on which a plurality of substrate holders are disposed, the substrate holders being rotatable about a second axis to perform a method in which a substantially uniform coating is applied to a substrate by moving at least one nozzle of a substrate coating station spaced from the substrate holders parallel to the substrate at a predetermined speed and a coating on the substrate, while the substrate holders are rotated about the respective axes.

From the EP 1 155 748 A1 An ejection method is known in which a predetermined amount of liquid is supplied from a liquid reservoir to an ejection valve, wherein prior to starting the ejection of the liquid, pressure is applied to the liquid by means of an urging member based on a predetermined specific value, a pressure near one Discharge port is kept at the predetermined specific value when the liquid ejection is finished, so that a discharge rate of the liquid is kept constant by the discharge port.

The EP 1 262 244 A2 discloses a device for coating a compressor piston with a rotation support device for rotatably supporting both ends of a piston and a pair of first coating material applicators mounted above the rotation support device so as to be movable up and down, the two coating material applicators each having a first nozzle each applying a coating material on an outer surface of the piston and simultaneously applied coating material to a uniform film thickness, wherein a second coating material applicator is provided having a second nozzle which applies coating material to a bridge portion of the piston ,

From the DE 10 2005 055 162 A1 A method of efficiently applying an insulating resin to ceramic lamination bodies having complex shapes is known. For this purpose, an application device is used which has a holding section for holding a ceramic lamination body, a nozzle head portion having a plurality of nozzles for ejecting an insulating resin, and a moving means for relatively moving the nozzle head portion along the coating direction, the positions of the openings of the nozzles and / or the diameters of the openings depending on the shapes of the side surfaces of the ceramic lamination body can be varied.

The US 8,409,666 B2 discloses a bicycle helmet manufacturing method comprising the steps of uniformly coating a base layer of an impact absorbing shell with a resin, coating the base layer with a protective resin layer, applying a pattern to the protective resin layer, and spraying a clear coat on the pattern.

The JP 2006 248573 A discloses a method for producing a film-bound can body in which a film is first prepared which is subsequently cured with ultraviolet irradiation. For film formation, ultraviolet curing ink is ejected from an ink jet printer to adhere the ink to the surface of a substrate, then an adhesive is applied, and heating and drying of the printing layer are performed. In a film bonding step, the printed film is applied to a cylindrical can body to set and cure the printed film on the can body in a subsequent ultraviolet irradiation step.

From the US 5,254,164 is a coating process for applying coatings is known in which the objects to be coated on radially aligned mandrels a turret and are held with negative pressure on the mandrels.

The US 5 288 322 A discloses an apparatus for applying a color pattern to textile articles having conveying means comprising a plurality of cylindrical article carriers, and to a plurality of printing stations for printing the articles which are relatively movably mounted to the article carriers, the article carriers being an extension of the respective applied textile article to ensure a reliable fixation of the textile article.

From the DE 675 593 C1 is a device for applying paint on objects which are rotated about its own axis and about a parallel to its second axis, known, wherein for zonal spraying of the workpieces circumferential bands for limiting the color areas on two opposite sides are arranged such that the Spray jet is limited immediately before the color surface of the two oppositely moving strand of an endless belt to the width of the ink zone to be produced.

The US 2010/330144 A1 discloses three-dimensional porous tubular scaffolds for cardiovascular, peripheral vascular, nerve conduction, bowel, bile duct, urinary tract, and bone repair / reconstruction, and methods and apparatus for making the same.

According to one of the Applicant known, printed unpublished prior art is for a painting of a Lackierobjekts, which may be in particular an aerosol can blank having a substantially cylindrical outer surface, a paint application to the, preferably previously printed, outer surface by means of a Roll arrangement provided. With the aid of the roller arrangement, paint from a storage container is first applied to a plurality of rollers aligned parallel to one another, wherein adjacent rollers roll against each other and thereby achieve a homogenization of a paint film. An applicator roller is finally in direct contact with the outer surface of the Lackierobjekts and applies the paint contact with the outer surface.

The object of the invention is to provide a painting device and a method for painting an outer surface of a Lackierobjekts in which a compact structure for the painting and a contactless paint application are guaranteed on the Lackierobjekts and operated in a small, enclosed volume of space or performed can occur without this undesirable paint mist.

This object is achieved for a painting device of the type mentioned with the feature of claim 1. It is provided that the paint delivery device is designed for providing a hydrostatic pressure on the paint and that the outlet nozzles are designed for an output of paint threads in, at least predominantly, in particular exclusively, dependence on the hydrostatic pressure on the paint. This refinement of the paint delivery device and the discharge nozzles ensures that the paint can be applied as a paint thread, ie as a compact strand without fogging of paint particles, and applied contactlessly to the outer surface of the paint object. In particular, no additional fluid, such as compressed air, is required to convey the paint from a reservoir to the outlet nozzle (s).

The discharge process for the paint threads depends essentially on the hydrostatic pressure applied by the paint delivery device to the paint, the viscosity of the paint, which is specified in most paints and can be adjusted by suitable temperature control at a certain interval, on the geometry of the outlet nozzle and from the distance between an orifice of the outlet nozzle and the painting object.

It is particularly advantageous if the lacquer can be discharged from the outlet nozzle without electrostatic or electrodynamic influences on the lacquer, so that the lacquer in this respect does not have to have any special properties, such as a specifiable electrical conductivity. Preferably, it is provided that for the construction of a hydrostatic pressure on the paint optionally a pressurized air supply of a reservoir is made or the paint is conveyed to the outlet nozzles with a pumping device. Preferably, the pumping means is arranged away from the outlet nozzles and is designed in particular as a paint delivery pump. Further, the invention provides that the outlet nozzles are geometrically designed so that the pressurized paint without an additional conveying fluid, in particular compressed air, emerges in a filamentary form from the outlet nozzle and can be applied to the outer surface of the oppositely arranged Lackierobjekts. It is preferably provided that the outlet nozzles are arranged relative to the receiving device, that the exiting paint threads are applied obliquely downwards or in the vertical direction down to the outer surface of the Lackierobjekts. By suitable selection of the geometry of the outlet nozzles and the hydrostatic pressure on the paint, which is provided by the paint conveyor, at least for small distances between Lackierobjekt and outlet nozzle an arbitrary orientation of the outlet nozzles are provided in space, so that the exiting paint threads can also be applied obliquely upward or vertically upwards on the outer surface of the Lackierobjekts. In the painting process, there is always a spacing between the output device and the paint object, so that it is a contactless painting process. In particular, such a coating method has the advantage that no spray mist is produced during paint application to the object to be painted, as occurs in compressed air spray systems.

It is expedient if the receiving device for a rotary mounting of the Lackierobjekts is formed about a rotational axis which is aligned transversely to a nozzle axis, which determines a Lackaustrittsrichtung from the dispensing nozzle. In such an orientation of the receiving device and the painting object to be accommodated against the at least one outlet nozzle, an advantageous application of paint to the painting object perpendicular / normal and thus parallel to a surface normal of the outer surface of the painting object is ensured. Furthermore, a relative movement between the object to be painted and the outlet nozzle can be achieved with the aid of the pivot bearing for the object to be painted around the axis of rotation. Thus, the painting object embodied by way of example as a cylinder sleeve can be coated with lacquer in an efficient manner on its entire outer surface, which at least substantially corresponds to a cylinder jacket surface. It is particularly advantageous if a cross-section of the painting object is circular and the receiving device is arranged with its axis of rotation relative to the outlet nozzle such that during a rotation of the painting object about the axis of rotation always an at least substantially equal distance between the painting object and outlet nozzle is present. The outlet nozzle is exemplarily designed as a circular cylindrical bore in a nozzle plate, wherein a bore axis is identical to the nozzle axis. Furthermore, it can be provided by way of example that the nozzle axis is aligned normally on an end face of the nozzle plate. It is particularly advantageous if only dispensing nozzles and no paint ejection-influencing, in particular none, fluid outlet nozzles for a pressurized auxiliary fluid, in particular compressed air, are arranged in the nozzle plate.

In an advantageous embodiment of the invention, it is provided that the output device is arranged linearly movable relative to the receiving device and comprises a controlled or controlled controllable actuating means for a linear movement along the axis of rotation. In this way, a superposition of two relative movements can be made during the painting process, by a full-scale application of paint is made possible on the outer surface of the Lackierobjekts. The first relative movement between the object to be painted and the dispensing nozzle is caused by the rotational movement of the receiving device about the axis of rotation. The second relative movement between the object to be painted and the dispensing nozzle takes place through the linear movement of the dispensing device along the axis of rotation. Accordingly, a paint thread discharged in a continuous or discontinuous manner from the discharge nozzle can be laid spirally or otherwise on the outer surface of the paint object. The adjusting means may be a fluidic drive or an electric drive, for example a pneumatic cylinder or an electric spindle drive, which is controlled by a suitable control device.

It is preferably provided that a plurality of output devices are arranged circumferentially circular to the axis of rotation. In this case, the dispensing devices can be arranged offset along the axis of rotation to allow an arrangement of dispensing nozzles with respect to the Lackierobjekt, in which with as few revolutions of the Lackierobjekts around the axis of rotation complete or at least provided in a predeterminable coating is possible. By way of example, it is provided that one or more of the output devices are arranged linearly movable relative to the receiving device and at least two output devices can be moved synchronously or independently of one another along the axis of rotation. It is preferably provided that nozzle axes adjacently arranged output device occupy an acute angle, in particular an angle less than 45 degrees, whereby a particularly compact arrangement of the output devices is made possible.

In a further embodiment of the invention it is provided that the output device comprises a plurality, in particular along a straight line aligned parallel to the axis of rotation, preferably arranged evenly distributed, dispensing nozzles. Preferably, the dispensing nozzles are arranged in a uniform pitch relative to one another, in which the lacquer threads impinging on the outer surface of the lacquer object reliably come into contact with adjacently applied lacquer threads, so that a closed lacquer surface can be created.

In a further embodiment of the invention, provision is made for a valve device to be formed between the paint delivery device and the delivery nozzle for a temporary interruption of the fluidically communicating connection. With the aid of the valve device, which is preferably an electromechanical valve, in particular a solenoid valve, is a highly dynamic influence on the paint flow between the paint conveyor and dispensing nozzle is possible. It is preferably provided that the valve device is arranged immediately upstream of the dispensing nozzle, so that a paint volume that can not be influenced by the switching position or control position of the valve device is kept as low as possible. As a result, an undesirable drop formation in the vicinity of the dispensing nozzle is reduced. By way of example, the valve device can be designed as a needle valve which, at a transition from a paint delivery channel, which can be called a valve chamber, to the dispensing nozzle, engages with a valve needle in a valve seat formed directly on the dispensing nozzle and thus minimizes the volume of paint that can not be influenced.

It is advantageous if the paint delivery device and / or the output device and / or the receiving device is assigned a tempering device, in particular a heating device, for a temperature control of the paint and / or the paint object. Since a job of the paint on the outer surface of the Lackierobjekts takes place as a paint thread, it is advantageous if the paint thread is easily flowable when hitting the outer surface to wet the largest possible surface area of the outer surface with paint. For this purpose, it is advantageous if the painting object can be heated to a favorable temperature for the paint with a tempering device, in particular a heating device, assigned to the receiving device. Additionally or alternatively it can be provided that the paint delivery device and / or the output device is associated with a tempering, with the aid of a temperature of the paint can be kept in a vorgebaren temperature interval to spend a stable paint thread from the dispensing nozzle. This is especially important when a rotational movement of the Lackierobjekts is performed around the axis of rotation at a high angular velocity to take this case due to aerodynamic effects no tearing of the paint thread in purchasing, creating a more uneven paint the outer surface of the Lackierobjekts would occur.

According to the invention, it is provided that the output device is arranged as a processing station on a machine frame and that the machine frame is assigned a plurality of movably mounted receiving devices which are designed for a, in particular discontinuous, transport of painting objects between the processing stations along a, in particular circular section, movement path. The machine frame is preferably a machine frame of a printing machine, on which several processing stations are provided for processing the painting object. In this case, the processing stations also include the intended for painting the Lackierobjekts output device and additional facilities and / or arrangements that are designed for printing the Lackierobjekts and / or preparing the Lackierobjekts on the painting and / or for further processing of the Lackierobjekts after painting. For a transport of the Lackierobjekte between the respective processing stations a plurality of receiving devices are provided which are arranged in particular on a common, rotatably mounted, workpiece rotary table, which is provided with a rotary drive. It is preferably provided that the rotary drive carries out a discontinuous movement, in particular a rotary step movement, of the workpiece rotary table and thus of the receiving devices. Thus, the receiving devices and each recorded on the receiving devices Lackierobjekte along a circular path-shaped movement path between the individual processing stations, which are preferably arranged in the same angular pitch and the same radial distance to a rotational axis of the rotary drive, are moved. The rotary drive can be, for example, an electric direct drive with a stator fixedly mounted on the machine frame and a rotor rotatably mounted with respect to the stator, in particular integrated in the workpiece rotary table, which performs the desired rotational movement about a preferably vertically oriented axis of rotation by charging with electrical energy , The receiving devices are preferably designed as mandrels, on which the sleeve-shaped Lackierobjekte can be plugged. Alternatively, the receiving means may also be formed as a chuck, in which the painting objects are partially inserted and tensioned.

It is further provided according to the invention that the output device along the path of movement downstream of a designed as an ink jet printing device, printing device is arranged, which is designed for at least partially printing the outer surface of the Lackierobjekts before performing the painting. The printing device is designed to carry out a contactless ink-jet printing process, which can also be referred to as a digital printing process and in which a distribution of printing ink can be determined individually for each painting object.

Furthermore, the invention provides that the processing stations and the receiving devices are accommodated in a volume of space that is bounded by boundary walls and separated from an environment and in which a constant room temperature and / or a predeterminable overpressure the environment is present. As a result, reproducible conditions for the printing process can be ensured. In addition to controlling or regulating the room temperature and / or the predeterminable overpressure, it is also possible to influence the prevailing gas composition in the room volume and / or to influence a prevailing moisture content in the room volume in the typically gaseous atmosphere in the room volume.

The object of the invention is achieved for a method for decorating an outer surface of a Lackierobjekts with the following steps: at least partially printing the outer surface of the Lackierobjekts with a first output device in a formed as an ink jet printing process, pressurized providing a paint from a paint conveyor to a dispensing nozzle of a second Output device and outputting of the paint through the dispensing nozzle on the painting object, wherein during the printing operation and / or during the painting a relative movement between at least one output device and the Lackierobjekt is carried out by means of a receiving device for the Lackierobjekt, wherein the relative movement at least one rotation of the Lackierobjekts to a Includes rotational axis relative to the output device, wherein a radial distance of the output devices to the painting object and an orientation of the Ausgabeinri tions against the object to be painted and a peripheral speed of the object to be painted are adapted to the flow properties of the paint to be processed in such a way that a paint thread is continuously applied to the outer surface of the object to be painted.

In an advantageous development of the method it is provided that the relative movement between a linear movement Paint object and dispensing nozzle along the axis of rotation comprises.

In a further refinement of the method, it is provided that linear movements are coordinated with a plurality of dispensing devices in such a way that lacquer threads of different dispensing devices are placed crossed on the outer surface of the object to be painted and this causes an advantageous wetting of the outer surface of the object to be painted with the applied lacquer.

In a further embodiment of the method it is provided that at least one dispensing nozzle is associated with a valve device, which performs a dynamic provision and shutdown of a fluidically communicating connection between paint conveyor and dispensing nozzle, in particular for adaptation to different product lengths of Lackierobjekts.

Figur 1

eine schematische Draufsicht auf eine Druckmaschine mit einem drehbeweglich gelagerten Werkstückrundtisch und mehreren Arbeitsstationen zur Bedruckung und Inspektion von zylindrischen Gegenständen,

Figur 2

eine schematische Vorderansicht einer als Druckstation ausgebildeten Arbeitsstation der Druckmaschine,

Figur 3

eine schematische Vorderansicht einer als Lackierstation ausgebildeten Arbeitsstation der Druckmaschine,

Figur 4

eine schematische Draufsicht auf die Lackierstation gemäß der Figur 3,

Figur 5

eine schematische Schnittdarstellung einer Ausgabeeinrichtung, die zur Bereitstellung von Lackfäden ausgebildet ist, und

Figur 6

eine stirnseitige Ansicht der Ausgabeeinrichtung gemäß der Figur 5.

An advantageous embodiment of the invention is shown in the drawing. Showing:

FIG. 1

a schematic plan view of a printing machine with a rotatably mounted workpiece rotary table and several workstations for printing and inspection of cylindrical objects,

FIG. 2

a schematic front view of a designed as a printing station workstation of the printing press,

FIG. 3

FIG. 2 is a schematic front view of a workstation of the printing machine designed as a varnishing station. FIG.

FIG. 4

a schematic plan view of the painting station according to the FIG. 3 .

FIG. 5

a schematic sectional view of an output device which is designed to provide lacquer threads, and

FIG. 6

an end view of the output device according to the FIG. 5 ,

One in the FIG. 1 schematically illustrated printing machine 1 comprises a rotatable about a rotation axis 2 mounted on a machine frame not shown workpiece rotary table 3 and a plurality, each paired on the workpiece rotary table 3, serving as receiving devices workpiece holders 4. The workpiece holders 4 are individually rotatable about rotational axes 5 with not shown drive means stored. The workpiece holders 4 are provided for receiving sleeve-shaped objects 6, in particular designed as aerosol can blanks or tube blanks, formed at least substantially with a circular-cylindrical cross-section. Preferably, the workpiece holders 4 are formed as pins on which the hollow body, in particular as a closed hollow cylinder, formed and also referred to as Lackierobjekte objects 6 can be plugged. By way of example, it is assumed that each of the workpiece holders 4 is assigned its own drive motor, which can be controlled separately and is not shown, and which enables a rotational movement of the respective workpiece holder 4 about the respective axis of rotation 5. This possibility for, in particular controlled, rotation of the respective workpiece holder 4 is in particular used in carrying out the printing operation and the painting process described in more detail below.

In one of the workpiece holders 4 during a rotary movement of the workpiece rotary table 3 about the rotation axis 2 swept annular portion-shaped area, which can be referred to as a movement path 7 and extending in the circumferential direction around the workpiece rotary table 3, a plurality of workstations 8 to 18 are arranged, leading to a processing and / or examination of the transported objects 6 are formed. Since it is in the view according to the FIG. 1 is a plan view and the workstations 9 to 17 are usually arranged in the vertical direction above the workpiece holders 4, the workstations are shown 9 to 17 only in dashed lines. The function and arrangement of the work stations 8 to 18 described in detail below, depending on the intended processing for the objects 6 freely selectable, it can also workstations with other functions are provided or completely eliminated.

The work station 8 is a loading station, also referred to as a feed station, on which the cylindrical objects 6 are pushed in pairs onto the workpiece holders 4 by a suitable transport device 19, which is coupled to a conveying system, not shown, for the cylindrical objects 6.

At the workstation 9, a neutralization of electrical charges, which may be present on an outer surface 25 of the article 6, is provided purely by way of example. Such neutralization is particularly advantageous in plastic articles 6 and may optionally accounts for objects 6 made of metal. For the electrical (electrostatic) neutralization of the objects 6, the workstation 9 comprises a non-illustrated neutralization arrangement, with which the discharge of the article 6 can be performed. By way of example, the neutralization arrangement comprises two electrodes arranged at a distance from each other, to which an electric alternating field is applied in each case by a control device likewise not shown in more detail. In this case, an electrical voltage and a frequency of the alternating electric field are matched in a manner to the distance of the electrodes, that in the vicinity of the electrodes existing gas, in particular air, can be ionized. With the help of the liberated ions, a charge balance with the electrical charges, which are present on the outer surface 25 of the article 6, take place. The now electrically neutral object 6 is then conveyed along the movement path 7 to the subsequent workstation 10.

Downstream along the path of movement 7, the workstation 10 is provided following the workstation 9, which is purely an example of a cleaning arrangement. By way of example, the cleaning station is designed as a suction device, which is designed for contactless suction of the outer surface 25 of the article 6.

On the downstream along the path of travel 7 downstream of the workstation 10 arranged workstation 11 is purely exemplary, an optical scanning of the cylindrical objects 6 to determine a rotational position of the cylindrical objects 6, for example, a correct rotational orientation of the cylindrical objects 6 for a on the Workstation 12 taking place printing to ensure. This is of particular importance when the outer surface of the objects 6 to be printed is provided with features which are intended to be fitted in a predetermined manner with the printed image to be applied. These features may be, for example, local embossing and / or embossing in and / or out of the outer surface of the article 6 and / or pre-printed areas, which in turn should serve as a primer for subsequent printing.

The object 6 is now in the course of a further rotational stepping movement of the workpiece rotary table 3 about the rotation axis 2 successively to the work station 12, 13 and 14 moves, which are each purely exemplarily designed as printing stations to each with the help of printing devices 51, as exemplified in the FIG. 2 are shown to be printed. When carrying out the printing operation, it is provided that the object 6, which is designed as an example with a circular-cylindrical cross-section, rotates about the in-mold FIG. 1 shown rotational axis 5 performs and during the rotational movement by a in the FIG. 2 schematically illustrated printhead 52, which is exemplarily an inkjet printhead, can be printed. During the printing operation, ink droplets (not shown) are dispensed from the printhead 52, which is arranged by way of example at a distance of 1 mm to 5 mm from the outer surface of the object 6 and which is driven by a pressure control device 53 with electrical signals. Preferably, the discharge nozzles 52 of the print head 52, which are likewise not illustrated in detail and exit at an exit surface 54, are aligned in such a way that the ink droplets are emitted at least almost perpendicularly to the outer surface 25 of the object 6.

The work station 15 arranged downstream of the workstation 14 along the movement path 7 is designed as an example as an inspection device and makes it possible to determine a print quality of the print image applied by the printing station 21 to the peripheral surface of the object 6.

The further workstation 16 is used for further processing of the cylindrical objects 6 by applying a protective lacquer to the printing at least on partial surfaces of the article 6, as described below in connection with FIGS FIGS. 3 to 6 will be described in more detail.

At the workstation 18 takes place an unloading process in which the cylindrical objects 6 are withdrawn by means of a transport device 20 of the mandrel-like workpiece holders 4 and fed to a non-illustrated further transport system.

The workpiece turntable 4 performs the stepwise processing of the cylindrical objects 6 at the respective workstations 8 to 18 a rotary step movement by the angle W, in which each paired workpiece holders 4 from one of the respective workstation 8 to 18 opposite position in one of each subsequent workstation 8 to 18 opposite position to be transported. In this case, the rotational step movement takes place as a sequence of acceleration from standstill, a deceleration from the achieved target speed and a subsequent downtime. Preferably, a non-illustrated drive for the workpiece turntable 3 is designed such that the acceleration and deceleration of the workpiece rotary table 3 are completely freely adjustable over a wide range and the downtime and to the requirements of processing the respective cylindrical objects 6 can be adapted to the workstations 8 to 18.

The in the FIGS. 3 to 6 Painting device shown in more detail is for applying a paint, in particular a clearcoat, formed on the outer surface 25 of the Lackierobjekts 6 and includes, by way of example, three similarly designed output devices 21, 22, 23, which according to the illustration of FIG. 3 are arranged circular to the axis of rotation 5 of the receiving device 4. As from the representation of FIG. 4 can be removed, the output devices 21, 22, 23 along the axis of rotation 2 of the receiving device 4 are arranged at different positions. By way of example, it is assumed that the output devices 21, 22, 23 can be moved parallel to the axis of rotation 2 by means of adjusting means (not shown), as symbolized by the respective movement arrows.

The output devices 21, 22, 23 are each formed identically, the structure is in the FIG. 5 shown in more detail and will be described in more detail below. Each of the output devices 21, 22, 23 has, by way of example, a number of outlet nozzles 26 on an output surface 24. By way of example, the outlet nozzles 26 are arranged along a straight line, in particular aligned parallel to the axis of rotation 5, in the same pitch, wherein positions of the outlet nozzles 26 in the FIG. 4 are shown schematically at the output device 22 by circles. How further from the FIG. 4 can be removed, the output means 21, 22, 23 are provided for the provision of lacquer threads on the outer surface 25 of the article 6. For example, as shown in FIG FIG. 4 during rotation of the article 6 about the axis of rotation 5, only an output of paint threads 27 through the output device 23, while the output devices 21 and 22 are deactivated by way of example at this time. In this case, a radial distance of the output devices 21, 22 and 23 to the object 6, an orientation of the output devices 21, 22 and 23 relative to the object 6 and a peripheral speed of the article 6 are adapted to flow properties of the paint to be processed such that one in the FIGS. 4 . 5 and 6 each schematically illustrated paint thread 27 is applied continuously to the outer surface 24 of the article 6. In this case, a diameter and a flow speed of the lacquer thread 27 are chosen so that when striking the article 6 due to the flow properties of the lacquer a closed lacquer surface on the outer surface 24 of the article 6 can be achieved.

As from the representation of FIG. 5 can be removed, the exemplary closer, for reasons of clarity, greatly simplified output device 21 comprises a main body 28 which is made of a dimensionally stable material, for example of a metallic material. In the exemplary plate-shaped base body 28 outlet nozzles 26 are introduced, the nozzle axes 45 are aligned, for example, normal to the output surface 24. Starting from one of the output surface 24 opposite mounting surface 29 receiving bores 30 for magnetic drives 32 are introduced into the main body 28. By way of example, the magnetic drives 32 are designed as magnetic coil drives having a circular-cylindrical shape and are completely accommodated in the main body 28. Each of the magnetic drives 32 comprises a linearly mounted nozzle needle 33, which passes through the base body 28, starting from the magnetic drive 32 and which projects into a valve chamber 34. The valve chamber 34 has a larger diameter than the nozzle needle 33, so that between the nozzle needle 33 and the valve body 34, an annular space 35 is formed. In the annular space 35 opens a supply channel 36, which is in fluidic communication with a supply connection 37. Connected to the supply connection 37 is a paint delivery device 38 which is designed by way of example as a paint pump and which in turn is coupled in fluidic communication with a storage container 39. Furthermore, the paint delivery device 38 is electrically connected to a paint control device 31, which is designed to provide electrical energy to the paint delivery device 38 in order to effect a promotion of paint from the reservoir 39 to the outlet nozzles 26. The magnetic actuators 32 are also electrically connected to the paint control device 31 and can be selectively controlled by the latter in order to selectively release or block a valve seat 40 provided at the transition between the valve body 34 and the outlet nozzle 26 with the aid of the respective nozzle needle 33. In this way, a fluidly communicating connection between the reservoir 39 via the supply port 37 and the supply channel 36 and the annular space 35 can be blocked or released to exit nozzle 26. By way of example, according to the illustration of FIG. 5 only one outlet nozzle 26 released from the associated nozzle needle 33, so that only there a paint thread 37 can be issued, which can be placed on the outer surface 24 of the oppositely arranged, rotated about the axis of rotation 5 item 6.

As from the representations of FIGS. 5 and 6 can be removed, takes place a promotion of the paint thread 27 exclusively by hydrostatic pressure on the paint, which from the reservoir 39 by means of the paint conveyor 38th is removed. The representation of the lacquer thread 27 is not selected to scale for reasons of clarity, in practice, a considerably thinner design of the outlet nozzle 26 and the resulting lacquer thread 27 is provided.

As shown in the dashed line in the FIG. 6 2, an optional air nozzle 41, which has a slot-shaped air outlet 42 which extends along its axis of rotation 2 at its greatest extent, can be arranged downstream of the output device 21 in the direction of rotation. With the aid of the air nozzle 41, an air jet is emitted perpendicular to the outer surface 25 of the article 6 in order to overcome a surface tension of the coated on the outer surface 25 paint thread 27 so that it spreads as widely as possible on the outer surface 25 and thus an advantageous distribution of the paint is possible.

By way of example, it is provided that the painting control device 31 and the pressure control device 53 are electrically connected, in particular as bus users, and are controlled in a coordinated manner by a higher-level control device (not shown), in particular a programmable logic controller (PLC).

Claims (12)

1. Coating device for coating an outer surface (25) of an item (6) to be coated like an aerosol can blank or a tube blank, having a discharge means (21, 22, 23) for providing a continuous or discontinuous flow of coating and having a receiving means (4) for receiving and positioning an item (6) to be coated opposite the discharge means (21, 22, 23), wherein the discharge means (21, 22, 23) comprises a discharge nozzle (26) and a coating conveying means (38) which is connected in a fluidically communicating manner to the discharge nozzle (26) and is configured for a pressurised conveying of coating to the discharge nozzle (26), wherein the coating conveying means (38) is configured to provide a hydrostatic pressure on the coating and wherein the discharge nozzles (26) are configured to discharge threads of coating (27), at least mainly, in particular exclusively subject to the hydrostatic pressure on the coating, wherein the discharge means (21, 22, 23) is arranged as a processing station (8 to 18) on a machine frame and wherein a plurality of movably mounted receiving means (4), which are configured to transport items (6) to be coated between the processing stations (8 to 18) along a movement path (7) are arranged at the machine frame, wherein the discharge means (21, 22, 23) is arranged along the movement path downstream of a printing device (51) which is configured as an ink-jet printing device and which is configured to at least partly print the outer surface (25) of the item (6) to be coated before the coating procedure is carried out, wherein the processing stations (8 to 18) and the receiving means (4) are accommodated in a spatial volume which is bordered by boundary walls and is separated from a surroundings and in which a constant room temperature and/or a predeterminable excess pressure compared to the surroundings is present.
2. Coating device according to Claim 1, characterised in that the receiving means (4) is configured to rotationally mount the item (6) to be coated about a rotational axis (5) which is oriented transversely to a nozzle axis (45) which determines a coating discharge direction from the discharge nozzle (26).
3. Coating device according to either Claim 1 or 2, characterised in that the discharge means (21, 22, 23) is arranged such that it is linearly movable with respect to the receiving means (4) and comprises an adjusting means which can be controlled in an open loop or closed loop for a linear movement along the rotational axis (5).
4. Coating device according to Claim 1, 2 or 3, characterised in that a plurality of discharge means (21, 22, 23) are arranged in a circulatory manner with respect to the rotational axis (5).
5. Coating device according to any one of the preceding claims, characterised in that the discharge means (21, 22, 23) comprises a plurality of discharge nozzles (26) which are preferably arranged in an identical spacing, in particular along a straight line oriented parallel to the rotational axis (5).
6. Coating device according to any one of the preceding claims, characterised in that a valve device (32, 33, 40) for a temporary interruption in the fluidically communicating connection is configured between the coating conveying means (38) and the discharge nozzle (26).
7. Coating device according to any one of the preceding claims, characterised in that the coating conveying means (38) and/or the discharge means (21, 22, 23) and/or the receiving means (4) is allocated a temperature-control means, in particular a heating means to control the temperature of the coating and/or of the item (6) to be coated.
8. Coating device according to any one of the preceding claims, characterised in that the receiving means (4) are configured for a discontinuous transport of the items (6) to be coated, between the processing stations (8 to 18) along a circle segment-shaped movement path (7).
9. Method for decorating an outer surface (25) of an item (6) to be coated like an aerosol can blank or a tube blank, comprising the steps: the at least partial printing of the outer surface (25) of the item (6) to be coated using a first discharge means (51) in a printing procedure configured in particular as an ink-jet printing method, the pressurised supply of a coating from a coating conveying means (38)to a discharge nozzle (26) of a second discharge means (21, 22, 23) and the discharge of the coating through the discharge nozzle (26) onto the item (6) to be coated, and during the printing procedure and/or during the coating procedure, a relative movement between at least one discharge means (21, 22, 23; 52) and the item (6) to be coated is performed by a receiving means (4) for the item (6) to be coated, the relative movement comprising at least one rotation of the item (6) to be coated about a rotational axis (5) with respect to the discharge means (21, 22, 23; 52), wherein a radial distance of the discharge means (21, 22, 23; 52) from the item (6) and an orientation of the discharge means (21, 22, 23; 52) with respect to the item (6) and a circumferential speed of the item (6) are adapted to the flow characteristics of the coating to be processed such that a thread of coating (27) is applied continuously to the outer surface (24) of the item (6).
10. Method according to claim 9, characterised in that the relative movement comprises a linear movement between the item (6) to be coated and the discharge nozzle (26) along the rotational axis (5).
11. Method according to claim 9, characterised in that linear movements of a plurality of discharge means (21, 22, 23) are coordinated such that threads of coating (27) from the different discharge means (21, 22, 23) are deposited in a crossed manner on the outer surface (25) of the item (6) to be coated, thereby achieving an advantageous wetting of the outer surface (25) of the item (6) to be coated with the applied coating.
12. Method according to claim 9, characterised in that allocated to at least one discharge nozzle (26) is a valve device (32, 33, 40) which performs a dynamic establishment and disconnection of a fluidically communicating connection between coating conveying means (38) and discharge nozzle (26), in particular to adapt to different product lengths of the item (6) to be coated.

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