DE202016103010U1 - Apparatus for direct inkjet printing of containers - Google Patents

Abstract

Device (1, 21) for directly printing on inkjet containers (2), comprising at least one carousel (3, 23) for holding the containers (2), and printheads (4, 4) at least part of the carousel (3, 23). 24), characterized by a flow guide (7, 17, 18, 27) for selectively supplying gas flows in a region between at least one print head (4, 24) and container (2).

Description

The invention relates to a device for direct inkjet printing of containers according to the preamble of claim 1.

As is known, containers can be directly printed on rotary machines during continuous transport of the containers. For this purpose, ink jet heads are preferably moved during printing with the containers. Due to the comparatively high transport speeds on such rotary machines, printheads and containers to be printed are exposed to a wind. This creates, for example, air turbulence which can affect the trajectories of the ink drops and cause undesirable distribution of ink mist in the area of the printheads and the containers.

As a remedy in the DE 10 2009 013 477 B4 Enclosures proposed for rotating on rotary machines printheads. The enclosures limit the spread of paint mist and reduce wind currents caused by air currents in the printhead area.

A disadvantage of such housings, however, is the correspondingly limited access to the printheads. For feeding, printing and removing the container, these and the housings must be moved relative to each other, for example by means of lifting devices, and / or the housings are to be opened and closed in a suitable manner. This causes an undesirable expenditure on equipment for lifting devices, pivot mechanisms, cam controls or the like.

There is therefore a need for a device for direct printing of containers, which allows a containment of disturbing air currents in the region between the printheads and the container alike as a simple supply and removal of the container.

The stated object is achieved with a device according to claim 1. Accordingly, this is for direct inkjet printing of containers, such as bottles, in particular PET bottles, or the like, formed and for this purpose comprises at least one carousel for holding the containers and at least partially circumferentially with the carousel tracking printheads.

According to the invention, the device comprises a flow guide for selectively supplying gas flows into an area between at least one print head and container.

The flow guide is oriented to direct a flow of gas, particularly air, between a container and a printhead to affect the flight of ink droplets. As a result, for example, a flow, which is caused by a suction of ink mist, counteracted. Alternatively, the wind can be counteracted, as described below.

The containers can be aligned on the carousel in particular relative to the print head, for example via a rotation about a container longitudinal axis.

In particular, the flow-guiding element may be a countercurrent device for generating gas flows that follow the printheads, which counteract the wind in a pressure range between the printhead and the container. As a result, caused by the transport movement of the carousel air turbulence or currents in the area of the printheads and the container can be reduced. This promotes proper ejection of ink drops in the print area and allows controlled handling of ink / ink mist, for example by suction in the area of the printheads. The gas flows are to be understood as countercurrents in the area of the print heads.

In particular, the flow guide may be oriented to the container and printhead such that a tangent applied to one end of the flow director is directed substantially in the direction of a region between the printhead and the container, preferably, it may penetrate or intersect that region.

The gas flows are in particular air flows. However, other technical gases are also conceivable.

The carousel includes, for example, circumferentially evenly and self-rotatable supports for the containers, such as turntables and centering for a stationary transport of the container on the carousel or swivel mount for a floor-free hanging transport of the container on the carousel.

Preferably, the flow guiding element or the countercurrent device comprises flow baffles which catch the airstream in catchment areas on the print heads, deflect them and guide them in the same direction as the direction of rotation of the carousel into the pressure areas. This allows a passively operated counterflow device mutatis mutandis such that the deflected gas flow through the transport movement of the printheads and containers on the carousel is produced. An additional actively operated countercurrent device is then unnecessary.

The collecting areas are preferably located on the side of the print heads facing away from the containers and / or above the print heads and / or below the print heads. The trapping areas then do not restrict the space available for ejecting ink drops or restricting access to the printheads for feeding / retrieving the trays. The collecting areas open towards the direction of rotation of the carousel forward.

The flow baffles preferably delimit flow channels which have a larger cross-section towards the collecting area than towards the pressure area. The flow channels thus taper towards the pressure area. This results in a direction of flow from the collecting area to the pressure area, in particular also in the event that the flow channel points towards the pressure area in the direction of rotation of the carousel facing forwards.

Preferably, the position of the flow baffles with respect to the print heads is adjustable, in particular manually or by motor. As a result, the gas flows can be adjusted specifically to a pressure gap formed between the print heads and the containers and / or to the travel wind caused by the transport speed. Preferably, the gas flows generated by the countercurrent device can be specifically adapted to compensate for the respective wind generated in the region of the printheads and the container.

Also contemplated is automatic control in which the flow between the container and printhead (e.g., directly next to the trajectory of the pressure droplets) is measured and the flow director is motorized depending on the measurement result. As a measured value, for example, alternatively or additionally, a camera inspection of the printed image on the printed container could serve.

Adjustable can be, for example, an angle of the flow caused by the flow. But also a distance of the flow guide to the container or print head.

Preferably, the flow guide element or the countercurrent device for blowing the pressure areas comprises at least one central compressed gas source with pressure lines to the print heads. Alternatively or additionally, the countercurrent direction can comprise decentralized blower for blowing the pressure areas. Decentralized fans are preferably individually powered by motors.

The central compressed gas source and / or decentralized fans are actively operated and can therefore be used independently of the transport speed of the printheads and containers to reduce or compensate for air currents generated by airstream. The strength of the flow can continue to represent a manipulated variable in the above regulation.

Preferably, the device further comprises suction for ink / color mist above and / or below and / or adjacent to the print areas. The exhaust systems are effective above and / or below the pressure ranges in a range in which gas flows from the flow control element or the countercurrent device at least partially compensate for the wind. As a result, such pressure mist can be controlled and effectively vacuumed.

Preferably, the carousel is designed for a ground-free and hanging in rotary brackets transport the container. This allows transport of the containers in neck handling and thus handling of the containers in an area that is not usually equipped by direct printing.

Preferably, the carousel is formed for a clamped on turntables stationary transport of the container. This allows a particularly stable positioning and orientation of the containers for direct printing.

A feeding and a removal of the container in and out of the carousel can be done in the neck handling.

Preferably, the printheads are mounted radially inwardly of the containers and outwardly on the carousel. This allows unimpeded access to the area of the print heads from the outside for feeding and removal of the containers on the carousel. The collecting areas are then preferably radially within the print heads and thus in an otherwise largely unused area of the carousel. Accordingly, for example, adjustment devices for flow baffles or the like can be arranged comparatively easily radially within the print heads on the carousel.

In a further advantageous embodiment, the printheads are arranged radially outside the container, pointing inwards and running over a predetermined machine angle with the containers. The printheads then run, for example, in the periphery of the carousel over the predetermined machine angle with the containers. The machine angle is then seen in the transport direction of the container between an inlet region and an exit area of the carousel. The supply and the removal of the containers are then not hindered by the running printheads.

Preferably, then several printheads on at least one carriage together in / against the direction of rotation of the carousel are oscillating movable. The printheads are then used to print a group of containers simultaneously while the printheads are traveling. The printheads are then returned to print on the next group of containers. This allows a high machine performance of the device.

Preferably, the carousel is continuously rotatable. This also enables high machine performance. The axis of rotation of the carousel is in particular vertically aligned and cuts in particular the center of the earth.

In particular, the containers are rotated relative to the carousel about a vertical axis during the printing.

It is also possible to arrange at least two, preferably three or more, printheads in a printing station, which moves along with the carousel, wherein the printheads are arranged in the same horizontal plane and the receptacle of the container of this printing station is vertically movable and the container after entering the containers in another plane transported in the carousel in the plane of the printheads.

Under ink is any kind of liquid or viscous decorating agent, i.a. Color, lacquer or commercial "ink" understood.

Preferably, the apparatus comprises a plurality of counter-current rotating carousels connected in series and each associated with a particular printing ink. This allows multi-color direct printing on containers having the aforementioned features and advantages.

Preferred embodiments of the invention are illustrated in the drawings. Show it:

1 a schematic representation of a first preferred embodiment of the device;

2 a schematic plan view of the first embodiment with a plurality of printing modules;

3 a schematic plan view of a printhead and to be printed container of the first embodiment with a passive countercurrent device;

4 a schematic plan view of a printhead and to be printed container of the first embodiment with an active countercurrent device;

5 a schematic plan view of a second preferred embodiment of the device;

6 a schematic representation of the second embodiment; and

7 a schematic representation of an enclosure for the container.

As the 1 can detect, includes the device 1 for direct printing of containers 2 at least a carousel 3 on the printheads 4 for direct printing of the containers 2 radially inside the container 2 lying, facing outward and permanently with the carousel 3 are arranged running along. For holding and aligning the containers 2 are at the carousel 3 in circumferentially even intervals turntable 5 and centering tulips 6 trained in a known manner. It would also be conceivable, however, rotating brackets for holding and aligning the bottom floor hanging 2 (not shown).

In the field of printheads 4 are accompanying flow guide elements or countercurrent devices 7 with flow baffles 7a arranged. The term "flow baffle" is defined functionally in terms of a flow conducting surface, wall or the like. The flow baffle 7a can be made of metal or plastic or other materials.

With signs 101 is schematically shown the bearing on which the carousel rotates. With 102 is a stator and with 103 a runner of a drive ( 102 . 103 ) of the carousel. character 104 indicates a linear guide of the centering tulips 6 ,

The flow guide elements 7 In this view, AA obscure the view of the printheads 4 ,

The 1 shows a schematic section along a in the 2 indicated section line AA through the carousel 3 , Preferably, the device comprises 1 other carousels in series 3.1 and 3.2 with appropriate function. The individual carousels 3 . 3.1 . 3.2 For example, they are to be understood as printing modules which are assigned to different printing inks. For multi-color printing or the like, further functionally corresponding carousels may also be provided in the device 1 to be available.

The 3 shows a schematic section from above along one in the 1 indicated section line BB and represents an enlargement of the in 1 indicated image lower left at the character BB dar. Furthermore illustrates the 3 the operating principle of the passive countercurrent device 7 (or flow guide) during the transport of the print heads 4 and the container 2 in the direction of rotation 3a of the carousel 3 , Accordingly, the transport movement causes a (in the 3 schematically indicated by block parts) Fahrtwind 8th ,

With the help of the countercurrent device 7 becomes airstream 8th collected and in the form of a gas flow 9 in a print area 10 between the printhead 4 and the container 2 diverted. The gas flow 9 affects the wind 8th in the printing area 10 at least partially compensating for proper ink ejection 11 and a suction of pressure mist 12 in the area of the print head 4 to enable.

As the 3 also schematically indicates, forms the flow guide 7 and in particular the flow baffle 7a around the printhead 4 leading around a flow channel 13 off, relative to the printhead 4 oncoming wind 8th in a catchment area 14 captures and in this way the gas flow 9 forces.

The flow direction of the gas flow 9 to the print area 10 This enforces that, for example, orthogonal to the direction of rotation 3a defined input-side cross-section 15 of the flow channel 13 to the catchment area 14 is larger than an output-side cross-section 16 to the print area 10 out.

The catchment area 14 is like in the 3 indicated, preferably on the container 2 opposite side 4a of the printhead 4 educated. To have unimpeded access to the turntables 5 or the like holders during feeding and when removing the container 2 to ensure is the catchment area 14 then radially inside the printheads 4 arranged horizontally.

Additionally or alternatively, the catchment area 14 above and / or below the printhead 4 be educated. For example, the flow channel could 13 in the form of a suitable to the printhead 4 be formed around running funnel or the like.

The flow guide 7 and in particular the flow baffle 7a could, for example, by means of a (in the 3 only schematically indicated) bracket 7b in its position relative to the printhead 4 be attached adjustable. For example, the holder could 7b for adjusting spatial coordinates x, y, z (see 1 and 3 ) and / or a rotational position α of the flow guide 7a with respect to the printhead 4 be educated.

The adjustment of the flow guide 7a is possible both manually and by motor. This allows the flow channel 13 to the airflow to be compensated in the pressure range 10 adjust, for example, the relative speed of the airstream 8th and / or the distance between the printhead 4 and the container 2 is predetermined.

The 4 shows in one of the 3 corresponding schematic representation of an alternative embodiment of a working as a countercurrent flow guide 17 with a central compressed air source 17a , a rotary distributor 17b and in the area of the printheads 4 ending pressure lines 17c for blowing in the pressure areas 10 essentially in the same direction as the direction of rotation 3a of the carousel 3 ,

The compressed air source 17a is in contrast to the flow guide 7 or flow baffle 7a actively driven and operates preferably independent of the rotational speed of the carousel 3 , Accordingly, gas flows can be 9 with the active countercurrent device or with the flow guide element formed thereby 17 particularly flexible to the flow conditions in the pressure range 10 adjust to the wind 8th compensate there at least proportionally.

Also indicated is another flow guide element operating as an actively driven countercurrent device 18 in the form of one with the printhead 4 circulating blower or the like. This is then preferably powered by an individual motor and can be just as flexible to the flow conditions in the pressure range 10 at wind 8th to adjust.

The described counterflow devices or flow guide elements 7 . 17 . 18 could also be combined with each other to the wind 8th counteracting gas flows 9 both economical and flexible in the printing sector 10 to create.

As a flow guide could also be a blade of a fan watch (not shown), which a directed flow in the pressure range 10 brings.

One (in the 1 and 3 indicated) printhead longitudinal axis 106 is particularly vertically aligned in the 3 and 4 she goes to the Picture plane into it. Along the print head longitudinal axis 106 a plurality of nozzles for ejecting ink is arranged.

In the field of printheads 4 , in particular above the pressure range 10 and / or below and / or adjacent, is preferably a suction 19 for the pressure mist 12 educated. This is representative only in the 3 schematically above the print head 4 indicated.

The 5 shows in the schematic plan view of a second preferred embodiment 21 the device with a carousel exemplified 23 , a printhead 24 , an entrance star 25 and an outlet star 26 , The second embodiment 21 differs from the first embodiment 1 essentially by the printhead 24 over a given machine angle in the direction of rotation 23a during a printing process with the containers 2 runs along and after completion of the printing process in the opposite direction 23b moves back again, in the sense of a partial oscillation of the printhead 24 ,

The 6 shows a schematic section through the second embodiment 21 along one in the 5 indicated section line AA. Accordingly, in the area of the printhead 24 a working as a countercurrent flow guide 27 with at least one flow baffle 27a educated. While running the printhead 24 with the container 2 in the direction of rotation 3a of the carousel 3 the flow baffle works 27a essentially in the same way as the flow baffle 7a the first embodiment 1 ,

Accordingly, the flow guide begins 27 relative to the printhead 24 oncoming wind 8th preferably in an upper collecting area 28 above the printhead 24 and / or in a lower catchment area 29 below the printhead 24 and directs a forced gas flow / counterflow in one of the flow guide element 27 limited flow channel towards the pressure area 10 ,

Also the flow guide 27 the second embodiment 21 is preferably in its position and / or rotational position with respect to the print head 24 Adjust to the gas flow / counterflow to the flow conditions in the pressure range 10 for at least proportionate compensation of the wind 8th adjust.

Schematically indicated in the 6 a further radially inside the container 2 lying protective wall 23c as well as a direct drive 23d of the carousel 3 and an optional direct drive for the turntable 5 ,

Preferably, multiple printheads 24 together on one in the direction of rotation 23a and in the opposite direction 23b of the carousel 3 oscillating transport unit 30 arranged. Multiple printheads 24 can then, for example, on a slide or the like together during printing with the respective associated containers 2 move along and in a pressure pause against the direction of rotation 23a move back. The containers 2 be in the second embodiment 21 preferably directly printed in groups.

In the second embodiment 21 are the printheads 24 radially outside the container 2 and formed facing inwards. Accordingly, the printheads become 24 only within a transport area of the infeed star 25 to the outlet star 26 with the containers 2 moved. This provides unhindered access to the containers from the outside during the feeding and removal of the containers 2 given.

The passive and / or active countercurrent devices described with respect to the first embodiment 7 . 17 . 18 and / or the suction 19 may also be present in the second embodiment.

The printheads 4 . 24 Suitable for direct inkjet printing on containers 2 such as bottles, cans or the like.

7 shows an enclosure 110 in which the container is 2 during printing by printhead 4 located. The enclosure includes lateral walls 110a . 110b and a lid 110c and the turntable 5 as ground. On the lid is a suction 111 arranged for pressure mist. The enclosure is not completely sealed, but includes a gap between the side walls 110a . 110b and the floor 5 is arranged. The side walls may also be a closed cylinder.

To counteract the flow created by the suction, is above the print head 4 a flow guide in the form of an injection 117 arranged by gas. The flow created by the injection counteracts the flow through the suction.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102009013477 B4 [0003]

Claims (15)

Contraption ( 1 . 21 ) for direct inkjet printing of containers ( 2 ), with at least one carousel ( 3 . 23 ) for holding the containers ( 2 ), and at least partially with the carousel ( 3 . 23 ) running printheads ( 4 . 24 ), characterized by a flow guide ( 7 . 17 . 18 . 27 ) for selectively feeding gas flows into an area between at least one print head ( 4 . 24 ) and containers ( 2 ). Apparatus according to claim 1, wherein the flow guide ( 7 . 17 . 18 . 27 ) as countercurrent means for generating with the printheads ( 4 . 24 ) accompanying gas flows ( 9 ), the airstream ( 8th ) in a printing area ( 10 ) between printhead ( 4 . 24 ) and containers ( 2 ) counteract. Apparatus according to claim 1 or 2, wherein the flow guide ( 7 . 27 ) Flow baffles ( 7a . 27a ), the airstream ( 8th ) in catchment areas ( 24 . 28 . 29 ) on the printheads ( 4 . 24 ), deflect and in the same direction with the direction of rotation ( 3a . 23a ) of the carousel ( 3 . 23 ) into the pressure areas ( 10 ) conduct. Apparatus according to claim 3, wherein the catchment areas ( 24 . 28 . 29 ) on the containers ( 2 ) facing away ( 4a ) of the print heads ( 4 ) and / or above the printheads ( 24 ) and / or below the printheads ( 24 ). Apparatus according to claim 3 or 4, wherein the flow baffles ( 7a . 27a ) Flow channels ( 10 ), which belong to the catchment area ( 24 . 28 . 29 ) a larger cross section ( 15 . 16 ) than to the print area ( 10 ). Device according to one of claims 3 to 5, wherein the position of the flow baffles ( 7a . 27a ) with respect to the printheads ( 4 . 24 ) is adjustable, in particular motor. Device according to one of the preceding claims, wherein the flow guiding element ( 17 . 18 ) for blowing the pressure areas ( 10 ) at least one central compressed gas source ( 17a ) with pressure lines ( 17c ) to the printheads ( 4 ) and / or decentralized fans. Device according to at least one of the preceding claims, further comprising suction devices ( 19 ) for pressure mist ( 12 ) above and / or below the pressure ranges ( 10 ). Device according to at least one of the preceding claims, wherein the carousel is designed for a bottom-free transport of the containers suspended in rotary holders. Device according to at least one of the preceding claims, wherein the carousel ( 3 . 23 ) for one on turntables ( 5 ), the transport of the containers ( 2 ) is trained. Device according to at least one of the preceding claims, wherein the print heads ( 4 ) radially inside the containers ( 2 ) and pointing outward on the carousel ( 3 ) are attached. Device according to at least one of the preceding claims, wherein the print heads ( 24 ) radially outside the container ( 2 ), pointing inwards and arranged to run along a predetermined machine angle with the containers. Apparatus according to claim 12, wherein a plurality of print heads ( 24 ) on at least one transport unit ( 30 ) together in / against the direction of rotation ( 23a ) of the carousel ( 23 ) are oscillatingly movable. Device according to at least one of the preceding claims, wherein the carousel ( 3 . 23 ) is formed continuously rotatable. Device according to at least one of the preceding claims, comprising a plurality of carousels connected in series and assigned to a specific printing ink ( 3 . 3.1 . 3.2 ) with flow guide elements ( 7 . 17 . 18 . 27 ).

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