EP1164010B1 - Device for decorating articles - Google Patents

Abstract

The appliance incorporates a continuously circulating conveyor (14) conveying the objects (18) each carried by a holder (16) along a conveyor track. The track has at least one handling unit and at least two transfer units, one of which is a supply unit, and the other a discharge unit. The object during printing is rotated on its lengthwise axis in a first direction , and, after printing, is rotated back to its original position in the opposite direction on its lengthwise axis.

Description

The invention relates to a device for decorating dimensionally stable individual objects, for. As for decorating bottles made of glass or plastic, using the screen printing process.

The use of modern printing inks, which are free of environmentally harmful components and curable by means of, for example, UV rays (see, for example, US Pat. No. 5,985,376), leads to a demand for printing machines, in particular screen printing machines with very high throughput.

Since light glass bottles, especially light glass bottles for drinks, are used increasingly in the future, it is not always possible to provide register marks on the bottles in the form of recesses, in particular in the bottom or at the bottom edge, into which any register pins or the like intervene. around the object in the circumferential direction z. B. in within the object carrying the holder to align in a certain way. This alignment is particularly necessary if, as usual in particular for multi-color printing, successively several partial printing images are applied to an object, which then complement each other to form an overall printed image.

An apparatus for printing on individual objects, which operates on this principle, is disclosed in US 3,842,733.

The invention according to claim 1 is based on the object of making available a device for decorating individual objects, for example bottles, in which the object is brought into a defined angular position in the holder and retains this angular position during the entire pass, so that a renewed Register or pass the object is no longer required. It should also continue the movement of the holder during the passage through the machine can be done in a precisely controllable and thus also exactly definable manner, so that achievable in particular with multiple printing the highest degree of accuracy and thus quality of the printed image is.

The solution to this problem can be summarized to the effect that the object about its longitudinal axis reciprocating rotational movements performs, which may be 360 °, possibly even a little more, the arrangement being such that the rotational movement in a first direction during the printing process takes place, in which the object is rolled on the screen printing stencil. After completion of the printing operation, the object is rotated back about its longitudinal axis back to its original position, wherein depending on the arrangement of the individual treatment stations along the transport path during this second rotational movement, the object can also pass a drying station, preferably a UV station and thereby just applied Printing ink is at least as far as dried and solidified that another partial printed image can be applied without affecting the quality of the first partial printed image would be affected.

As a particularly expedient embodiment has been found, in which the holders or their receptacles for the objects via a pivotally mounted, movable with the holder toothed element is rotated, which is in engagement with a gear attached to the receptacle, this toothed element is provided with a cam roller which engages in a mounted on the machine frame first curve whose course is chosen so that during the movement of the holder along the transport path along which the curve runs, the above-described rotations of the object about its longitudinal axis be effected. Such curves can be carried out with extremely great precision, and in the case of an endless curve, in which the cam roller is always in engagement with the curve, also a guarantee for maintaining a position of the holder and thus of the fixed in the latter object is given can be defined and controlled at any point of the transport path.

On the other hand, using a curve with cam rollers makes it impossible to rotate the object in certain sections along the transport path. This can be achieved without any special effort in that the curve is substantially parallel to the transport path in the respective sections. This is z. B. be useful in the areas of the transport path in which the objects to be printed are entered into the device or the printed objects are removed from the device. In either case, such a transfer will be easier to accomplish if the brackets do not rotate.

The reciprocating rotation of the objects is particularly advantageous for objects which od laterally projecting extensions od over the contour thereof. The like., For. As handles or handles are provided, since these require only one-way rotation in a footprint that is not present in the majority of cases. In any case, there is the possibility of the objects during the conveyance, for example, during transport on the belt or during transfer depending on the position of the handle or, if such is not present, for example, from the position of a seam on the outer surface of the Object is designed to align, so that the objects occupy a defined angular position in the circumferential direction during insertion into the respective holder relative to this, which is then maintained during the entire run through the treatment stations.

Furthermore, the invention relates to a device for Bedrukken dimensionally stable individual objects with a continuously circulating transport device for the transport of each carried a holder objects along a transport path, in which the transport device is provided with an odd number of holders for the objects and in the transport direction behind each at least two printing stations a drying station is provided and each time the objects through the transport path printing takes place only in one of the at least two printing stations located in front of the common drying station and the printing stations, in which an object is printed during one revolution, have a distance from each other which is an even multiple of the distance of two adjacent recordings in the transport direction, and the distance between two Printing stations, which are arranged in the transport direction in front of a common drying station, an odd multiple of the distance between two adjacent recordings amounts. The above-described arrangement of the printing stations and the drying stations has the advantage of lower investment costs, since not every screen printing station needs to be followed by a special drying station. Furthermore, this device allows greater flexibility in its applicability, since it is possible to provide, for example, an object with a multicolor print, the number of colors corresponding to the number of printing stations with which the device is provided. On the other hand, it is possible to use the device for printing objects, each with a printed image, which consists of partial printing images whose number z. B. corresponds to half of the printing stations located in the machine. It would be compared to the first application, the double performance, based on the number of printed objects per unit time to achieve.

Fig. 1

eine perspektivische Ansicht einer Druckmaschine, wobei die dem Betrachter zugekehrten Handhabungs- und Behandlungsstationen zur Erzielung einer besseren Übersicht weggelassen sind,

Fig. 2A

eine Draufsicht der Transporteinrichtung der Druckmaschine für die zu behandelnden Objekte in einer ersten Position der Steuerungseinrichtung für die Halterungen,

Fig. 2B

eine der Fig. 2A entsprechende Darstellung, in welcher die Steuerungseinrichtung für die Halterungen eine andere Position einnimmt,

Fig. 3

eine Ansicht einer Halterung mit darin befindlichem Objekt etwa in Richtung der Pfeile III-III der Fig. 2,

Fig. 4

eine Ansicht der Halterung etwa in Richtung des Pfeiles IV der Fig. 3,

Fig. 5

eine Draufsicht der die Rotation der Objekte bewirkenden Kurve,

Fig. 6

eine Ansicht etwa in Richtung des Pfeiles VI der Fig. 2A, wobei in Fig. 6 Teile weggelassen sind,

Fig. 7

eine Draufsicht, die etwa der Fig. 6 entspricht, wobei weitere Teile weggelassen sind.

In the drawing, an apparatus for printing glass bottles is shown in the diagram as an embodiment of the invention. Show it:

Fig. 1

a perspective view of a printing machine, wherein the viewer facing handling and treatment stations are omitted for clarity,

Fig. 2A

a top view of the transport device of the printing machine for the objects to be treated in a first position of the controller for the brackets,

Fig. 2B

2 is a representation corresponding to FIG. 2A, in which the control device for the holders occupies a different position,

Fig. 3

a view of a holder with therein object approximately in the direction of arrows III-III of Fig. 2,

Fig. 4

a view of the holder approximately in the direction of arrow IV of Fig. 3,

Fig. 5

a top view of the rotation of the objects effecting curve,

Fig. 6

a view approximately in the direction of arrow VI of Fig. 2A, wherein in Fig. 6 parts are omitted,

Fig. 7

a plan view corresponding approximately to the Fig. 6, wherein further parts are omitted.

The printing press 10 has an annular disk 14 which continuously revolves in the direction of the arrow 12 and to which holders 16 for the objects 18 to be decorated are attached at regular intervals over the circumference. Along the circumference of the annular disc 14, the necessary for the handling and treatment of objects facilities, such as transfer stations with the transfer devices 22 and 30, screen printing stations I to VI and drying stations A to C are arranged. In Fig. 1 of the drawing transfer stations and the screen printing stations I and II are not shown for clarity.

In particular, Fig. 2A shows that in the direction of rotation 12, which corresponds to the transport direction of the objects 18 in the printing press, after each two printing stations I and II, III and IV or V and VI, a drying station A or B or C is arranged , It follows that, if the ink must be dried after each printing operation, the object is printed in each case only in one of the two located in the transport direction 12 before a drying station screen printing station. In this case, during a passage of an object through the device, this can only be printed in three of the screen printing stations, with the result that for the application of a printed image which contains six colors, two passes of the object are required. Consequently, the printing stations can be subdivided into two groups, with the printing stations of the first group each applying a printed image on the first passage of the object. The printing stations I, IV and V belong to this group in the exemplary embodiment shown in the drawing. The printing stations II, III and VI, in which a partial print image is only applied during the second pass under the said condition, belong to the second group. It follows that when printing the objects during the first pass the printing stations II, III and VI of the second group are passed, without causing a printing occurs. The same applies to the printing stations of the first group during the second pass of the objects. From Fig. 2 it follows that the distance between the printing stations I and IV, in which the first two successive imprints are performed during the first pass, the distance of ten brackets 16 corresponds. The distance between the printing station IV and the printing station V, in which the third printing takes place during the first pass corresponds to the distance of four brackets 16 in radians. The distance between the printing station V and the printing station II, in which the fourth printing operation takes place in two passes of the objects, corresponds to the spacing of sixteen holders 16. The distance of the printing station III, in which the fifth printing is performed, corresponds to the printing station II the distance of four brackets. Finally, the distance between the printing station III and the printing station VI, in which the last printing is performed, the distance of ten brackets.

Due to the fact that an odd number of shots, namely, twenty-seven, is provided, the printing stations of the two aforementioned groups in the circumferential direction, ie in the transport direction 12, offset from each other so that the Astand between the printing stations of a group of the Printing stations of the other group each an odd multiple of the distance between two adjacent recordings. For this purpose, reference is made in particular to FIGS. 2A and 2B of the drawing.

The objects 18 to be printed are fed to the printing press 10 via a conveyor belt 20 (FIGS. 2A, 2B) on which the objects are arranged upright. The transfer of the objects 18 to be printed from the conveyor belt 20 into one of the holders 16 of the printing machine takes place in the feed station using a first transfer device 22 which has a plate 24 rotating continuously about a vertical axis in the direction of the arrow 23, with three on its Perimeter at equal intervals on its underside near the circumference mounted grippers 26 (Fig. 6, 7) is provided. Each gripper 26 detects the first in the transport direction 28 of the conveyor belt 20 to be printed object 18 and performs it in the course of the continuous rotation of the plate 24 in the region of each located in the feed station of the printing machine 10 bracket 16th

In the conveying direction 28 of the conveyor belt 20 extending substantially tangentially to the transport device of the printing press 10, the conveyor belt 20 behind the first transfer device 22 is provided at a short distance from the same a second transfer device 30 which is formed in the same way as the first transfer device 22 and in the transport direction 12 of the transport device 14 is arranged in front of this and serves to remove the finished printed bottles of each of the removal station continuous holder 16. The removed bottles are also parked on the conveyor belt 20, which thus also serves to promote the printed bottles.

When the object passes through the machine twice, only every second object arriving in the removal station is provided with a complete print image, so that only every second object, namely the completely printed object, for example, with all colors, is removed from the respective object by means of the transfer device Holder 16 removed becomes. This has the consequence that only every second holder 16, which passes through the feed, is empty and therefore only in every second holder by the transfer device 22, an object to be printed can be introduced. In the embodiment shown in the drawing, therefore, the two transfer devices 22, 30 are provided with only three grippers 26 which are arranged at equal intervals of 120 ° in radians around the circumference of the respective transfer device. It is obvious that in each case when an object 18 '(FIGS. 6, 7) passes the two transfer devices 22 and 30 for carrying out the second circulation after the first pass has ended, that peripheral area of the respective transfer device 22 or 30 passes through the removal station or feed station, to which no gripper is attached or such, if present, is not operated.

If the objects are printed in only one of the two aforementioned groups of printing stations and thus led out of the machine after a run, the transfer devices 22, 30 are provided with six grippers, which then have a distance of 60 ° in radians each other, since Each object arriving in the removal station must be removed by the transfer device 30 and thus an object must be entered in the delivery station into each of these passing holders by means of the transfer devices 22.

Instead of the plate 24 shown in the drawing, the transfer devices 22, 30 with other peripheral devices, such. As chain conveyors whose course can be adapted to the circular transport path of the transport device 14, or be provided by other means.

The printing machine 10 shown in the drawing is, as already mentioned, provided with twenty-seven brackets 16, that is, an odd number of brackets whose configuration is shown in particular in FIGS. 3 and 4. Each holder 16 has a lower support part 32 in the form of a Receiving and an upper support member 34 which is formed like a spike in the embodiment shown in the drawing and engages in its operative position, for example, in the opening at the neck of a bottle-like object 18. This upper support member 34 may be conically tapered in the usual way to its free end. It is guided on two vertical rods 36 which are supported by a mounted on the annular disc 14 base 38. The upper support member 34 is supported by a carriage 40 to which a rotatable about a horizontal axis cam roller 42 is mounted, which is engaged in the position of the holder 16 shown in Fig. 3 with a cam portion 44, the part of a circular, on Machine frame attached first curve 46 is.

The approximately plate-shaped lower support member 32 is supported by a coaxial shaft 48, at the receiving end 32 facing away from a gear 50 is fixed. With the latter, a toothed segment 52 is engaged, which is rotatably mounted on the annular disc 14 about a vertical axis 54.

On a projection 56 of the toothed segment 52, a cam roller 58 is mounted, which engages in a second curve 60. The latter is stationarily mounted on the machine frame below the transport device representing annular disc 14. The course of along the entire defined by the annular disc 14 endless transport path extending curve 60 is chosen so that by a take place during the transport movement of the holder 16 pivoting the cam roller 58 and thus of the toothed segment 52 about the axis 54, a rotation of the gear 50 and Thus, the receptacle 32 is effected such that the object 18 carried by the support members 32, 34 is rotated about its longitudinal axis with respect to its circumference, depending on the angular positions to be taken in certain treatment stations. In this case, the upper non-driven support member 34 is taken from the object 18.

The course of the curve 60 along the transport path for the objects, which causes a reciprocating pivoting of the toothed segment 52, can be seen in particular in FIG.

As long as the respective holder 16 is located in a region of the curve 46 in which the cam roller 42 assigned to the holder occupies the position shown in FIG. 3 of the drawing and presses the upper holder member against the object seated in the receiver 32, the latter is shown in FIG Bracket 16 fixed so that it can not move relative to the two Halterunsteilen. For this purpose, it is expedient that the upper support member 34 is mounted in a conventional manner about the longitudinal axis of the object 18 rotatably mounted on its carriage 40. To remove a printed object from the holder 16 and to insert an object to be printed in the same, the holder must be opened. For this purpose, the upper support member 34 is moved vertically. This is effected in the region of the removal station and the feed station by a corresponding course of the curve 46, which is provided in the region of the latter two stations with a stationary portion 62 which is offset from the main portion of the curve 46 upwards by a distance which sufficient to raise in the region of a first transition portion 64 between the main portion and the upper cam portion 62, the cam roller 42 and thus the carriage 40 so far that the upper support member 34 is disengaged from the object in the holder. The arrangement is such that at the latest at the moment of release of the object 18 by the upwardly displaced second support member 34 it is detected by one of the gripper 26 of the second transfer station 30 and held by this gripper, which then immediately performs an upward movement, to lift the object out of the receptacle 32 and to bring it in the course of the further rotation of the plate 24 in a position above the belt 20 and then by means of a downward movement on the belt 20, on which the object is then transported. The object thus retains during conveyance through the belt 20 during the pass through the treatment stations and when removed on the belt 20 after printing and in the transfer stations its standing position unchanged.

During the further transport of the now empty holder along the area in which the upper curve section 62 is, the holder remains open, so that in the shortly following feeding a new object to be printed by a gripper 26 of the first transfer means 22 in the Is brought portion of the open bracket 16 and inserted by a downward movement of the gripper in the receptacle 32 of the holder. The vertical movement component of each gripper 26, which causes the insertion of the object to be imaged in the receptacle 32 or the lifting of the printed object from this, allows an embodiment of the holder 16, in which the receptacles 32 need not perform vertical movement.

The process of inserting the object 18 into the holder 16 must be completed when the holder in the course of its transport movement in the direction of the arrow 12 reaches the second transition section 66 between the upper curve 62 and the curve main section 46. In this second transition section, the second support member 34 is moved by corresponding lowering of the cam roller 42 down to its operative position, in which the cam roller is again at the level of the main curve portion 46, and then in the further course of the transport movement is performed in the latter until it returns to the area of the first transition section 64.

In a stationary arrangement of the two transition sections 64 and 66 in the position shown in FIG. 1, each holder 16 would be opened in each first circulation in the first transition region 64 and remain open until passing through the second transition section 62. However, such an arrangement is not possible if the objects 18 travel more than one round in the printing press before they exit the respective holder of the transport device are taken out. In order to enable a treatment of the objects in which they perform more than one circulation, in the embodiment of the invention shown in the drawing along the upper curve portion 62, a below it located second curve portion 44 is provided, which is also arranged stationary. Further, below the respective transition section 64 and 66, a linear transition section 68, 70 is provided, wherein in each case an inclined transition section 64 and 66 and a linear transition section 68, 70 are mounted on a common carrier 72 and 74, the function of a switch Has. In particular, Fig. 1 of the drawing shows that by appropriate vertical displacement of the two carriers 72 and 74, a respective requirements corresponding curve can be adjusted.

Since in the embodiment shown in the drawing each two printing stations is arranged downstream of a common drying station, as already explained, six times printing each object this would pass through the transport path of the printing press 10 almost twice and introduced by the transfer device 22 in the printing machine 10 object first are printed in the printing station I, whereupon the printed image applied there is dried in the drying station A, before the second printed image is applied to the same object in the printing station IV. This second print image is dried in the drying station B, whereupon the object in the printing station V following the drying station B is provided with the third print, which is dried in the drying station C. The latter is located in front of the removal station to which the second transfer device 30 is assigned.

Since the object provided with three print images at this point in the stations II, III and VI is still to be provided with a total of three further print images, it is not taken out of the press after this first run. Rather, the two supports 72, 74 are displaced upwards into the position according to FIG. 1, in which the horizontal connecting sections 68, 70 establish the connection between the lower curved section 44 and the curved main section 46. Since the cam portion 44 is at the same height as the cam main portion 46, the cam roller 42 of the upper support member 34 does not undergo a change in its height so that the second pass support member 34 remains engaged with the object 18 '(Figure 6) , At the end of the second pass, the two carriers 72, 74 are moved into the position shown in Fig. 1 of the drawing upon reaching the removal station with the result that the cam roller 42 of the next support 72 reaching the holder 16 is moved upward and the second support member 34 disengages from the object 18, so that the latter can be removed in the manner already described from the printing machine 10 by a gripper of the second transfer means 30.

In the case of the above-described six-fold printing of each object, every second object reaching the removal station is taken out of its holder of the transport device 14. Accordingly, only every second arriving in the feeder station is empty and to be provided with an object to be printed. Consequently, the carriers 72, 74 are to be adjusted after each passage of an object. This has the consequence that in the portion of the transport path between the two straps 72, 74, the cam rollers 42 of this area passing brackets 16 are alternately performed in the lower curve portion 44 and the upper curve portion 62, as opened by two immediately consecutive brackets 16, the one and the other is closed.

In the embodiment shown in the drawing, each of the two supports 72, 74 is provided with an extension 76 on which a cam roller 78 is mounted. This cooperates with a circumferential curve 80. Both curves 80 are rotated via a common toothed belt 82. Point of time the displacement of the respective carrier 72, 74 results at a certain rotational speed of the respective curve 80 from the course of the same. It is of course also possible, deviating from the representation in the drawing (Fig. 1) to provide a separate drive for each carrier. In this case, both carriers 72, 74 independently, z. B. timed, operated.

In particular, Fig. 5 reveals the course of the second curve 60, in which the cam rollers 58 of the toothed segments 52, on which an example in Fig. 5 is shown, all holders 16 are guided. In particular, the course of the curve 60 is selected so that in each printing station I to VI, the curve 60 in the transport direction 12 has a rising portion 84 a, which begins shortly before the point at which the object 18 comes into contact with the screen printing stencil, and ends shortly after the point at which the printing process ends. At this rising curve portion 84a is followed by a falling curve portion 85a, which extends to the beginning of the next, again rising curve portion 84b. "Rising" curve section here means that the curve 60 in the transport direction 12 undergoes an increase in diameter, while "falling" curve section means that the curve 60 in this section in the transport direction 12 undergoes a reduction in diameter. In each rising curve section, a pivoting movement is transmitted to the toothed segment 52 which, via the toothed wheel 50, rotates the bottle 18 held by the receptacle 32 by up to 360 ° and possibly also beyond. The rising portion is assigned to a respective printing station, so that the rotation of the object 18 in a first direction in which it rolls on the screen printing stencil.

Fig. 2A of the drawing shows in connection with the printing station I, the position of the toothed segment 52, not shown in Fig. 2A holder in the transport movement in the direction of arrow 12 straight in the front in the transport direction region of the printing station I rising Section 84a of the curve 60 has run in and thus has begun the first clockwise rotation of the associated holder with the bottle about its longitudinal axis. At this time, the screen printing stencil 89 is in contact with the object to be decorated. This is generally achieved by an appropriate positioning of the squeegee 90, by which the screen printing stencil 89 is pressed against the surface to be printed of the object. In the further course of the printing process, the object is unrolled on the template 89, the squeegee 90 undergoes a corresponding synchronous displacement to the end position 90 ', in which the printing operation is terminated. Fig. 2B shows that in this position 52 ', the sector gear has almost completed its rotation. This also corresponds to the position 58 'of the cam follower 58 which is near the transition 86 (Figure 5) from the rising portion 84a to the falling portion 85a. The vertical axis of rotation of the toothed segment, which moves in a circular path in contrast to the cam roller 58, assumes the position 54 '.

For example, in the position 90 'located squeegee, the stencil 89, which has undergone a slight pivoting about the vertical axis 91 during the printing operation with the doctor brought out of contact with the object by the squeegee 90 is slightly withdrawn from the object with the Result that due to the elasticity of the stencil this comes out of contact with the object.

The aforementioned Elstizität the stencil can lead to a certain delay, so a deformation of the template. However, since all occurring during the printing process movements in each case only one direction run - the objects rotate during the printing process in a clockwise direction about its longitudinal axis, which inevitably results in the direction of movement of the doctor in the transport direction 12 - occurs the template delay in all printing stations in the same direction , so that the position of the applied in the individual printing stations partial print images to each other visually not changed.

When passing the following falling curve portion 85a (FIG. 5), the toothed segment 52, after it had come to a stop in the transition region 86, pivoted back again by the same angle of at least 360 ° in its initial position, with the result that the object again in his starting position is turned back. After reaching the position 90 ', the squeegee 90 is moved back to its original position. This also applies to the template 89, if this had been postponed during the printing process.

The above-described movements of the holders and thus of the objects take place in connection with the passage of each printing station and immediately following the printing process, so that again reaching the printing station II associated rising curve portion 84b (Fig. 5) again a rotational movement of the object in the first direction takes place. This is followed in turn by a falling curve section 85b. As it passes, the bottle is rotated back counterclockwise to its original position. However, the screen printing stencil station II remains out of contact with the object, which had previously been printed in the station I and the station II happened only on the way to the drying direction A behind it in the transport direction 12. The drying process may already begin on passing the falling portion 85b of the curve 60 and extend to the beginning of the following rising portion 84c associated with the printing station III. In the drying station A, the drying of the printed image applied in the printing station I takes place. After the drying process, the object passes the next printing station III, without a printing process takes place. Again, the template thus remains in the printing station III out of contact with the object 18. While passing the printing station III is also according to the rising portion 84c, a rotation of the object in the first direction and then according to the subsequent falling portion 85c the Rotation back to the starting position, which occupies the object when the cam roller 58 in the inner transition region 86 of the curve 60 between the falling curve section 85c and the subsequent rising curve section 84d, which is associated with the printing station IV is located. In the latter, after the object has previously been subjected to the first drying operation in the drying station A, the application of the second printed image takes place, wherein the object is rotated about its longitudinal axis in the first direction during the passage of the curve section 84d in the manner already described. During the passage of the subsequent curve section 85c, the object reaches the area of the drying station B, in which the printing ink applied in station IV is dried. Since the object from its circumferential angular position, which it occupies after completion of the printing process in the station IV, again for the possibly taking place in the station V printing process must be returned to its original position, the entire peripheral surface is at least as far as they a print image is provided exposed to the action of the radiation in the drying station B, so that a sufficient drying is ensured.

The same applies to the other drying stations A and C. The course of the curve 60 is selected so that during the printing and irradiation the object rotates at a constant speed about its longitudinal axis.

After passing through the drying station B, the cam roller 58 of the toothed segment 52 in the next printing station V associated rising curve section 84e passes with the result that the object to be printed in the printing direction, ie the first direction, is rotated, wherein in the printing station V at the first pass the application of the third printed image takes place. Thus, the template of the printing station is brought into contact with the object here. When passing the subsequent falling curve section 85e, the return rotation of the object about its longitudinal axis to the starting position takes place again. The Object which had been printed in the station V passes the station VI without coming into contact with the printing stencil thereof. The printing station VI is also associated with a rising curve section 84f, followed by a falling section 85f. As the latter passes, the object passes into the area of the drying station C in which the ink applied in the printing station V is dried.

The region of the curve 60 located behind the drying station C in the transporting direction 12 runs essentially coaxially to the axis of rotation 88 of the conveyor 14, since in the area of the transfer stations 30 and 22 there is no rotation of the objects about their longitudinal axis so as to simplify the transfer.

In the course of the previous run through the printing stations I to VI, the object was printed only in three printing stations, namely the stations I, IV and V. If the object is also to be printed in the other printing stations II, III and VI, a repeated pass through the machine is required. This assumes that the holder 16 remains closed during the passage of the feed station and the removal station, that is, the upper support member 34 remains in its lower position, which is shown for example in Fig. 3. Therefore, it is necessary to adjust the carrier 72 so that the horizontally extending connecting portion 72 makes the connection between the cam main portion 76 and the lower cam portion 44 in the region of supply and removal station, so that the cam roller 42 maintains its lower position and the holder remains closed and thus passes through the supply and removal station and, after passing through the correspondingly adjusted second carrier 74, continues its second passage.

Since the bottle located in the holder had already been printed in the station I in the first pass, the bottle remains when passing through the station I out of contact with the screen stencil of the same, but they already in Rotational movements described in connection with the first passage due to the guidance of the cam roller 58 in the curve 60 performs. This also applies when passing the printing station II, but here the bottle receives its fourth printing. Thereafter, the bottle again passes for drying the drying station A. In the course of further movement in the transport direction 12, the bottle is provided with a further printed image in the stations III, and after drying in the drying station B, in the station VI. The applied in the station VI printed image is dried in the drying station C before the now z. B. six different colors finished printed bottle in the removal station is led out of the press.

Since the holder 16 must be opened to this end, it is necessary to provide the first carrier 72 immediately before the holder 16 arrives in the removal station so that the first transition section 64, which is inclined with respect to the horizontal, reaches its operative position which makes the connection between the main curve portion 46 and the likewise stationary upper curve portion 62, so that the holder 16 is opened when passing through the first transition portion 64. Since in this area the holder does not perform any rotational movement, it is readily possible to take the bottle from the open holder in the removal station and to insert a bottle to be printed into this now empty holder when passing through the feed station. Upon reaching the second carrier 74, this must be set as shown in FIG. 1 so that in turn the connection between the upper curve section 62 and the subsequent thereto in the transport direction 12 curve main section 46 is made. When passing through the second transition section 66, the holder is closed, so that the gripper of the transfer device, which had held the bottle until then, can be opened.

The bottle then passes through the printing machine in the manner described above, taking a total of nearly 720 ° travels before it is removed from the machine. In this case, it is necessary to adjust the carriers 64 and 66 after passing each holder, since the bottles respectively arriving in the removal station are alternately those which are ready to be printed and brought out of the machine, and such (18 '; in Fig. 6) which require a second pass through the printing machine for application of the second series of print images.

Notwithstanding the procedure described above, it is also possible, in such cases in which the objects are to be provided with only three print images, ie, for example, for producing a three-color print image, the objects out after only one pass from the machine, where a group of objects in the printing stations I, IV and V and the other, equally large group of objects in the printing stations II, III and VI is printed. The objects of both groups can be provided with the same print images. But it is also possible to provide the two groups of objects with different print images.

In any case, an accurate alignment of the objects is ensured in the circumferential direction, since, after the respective holder 16 is finally closed, the object relative to the holder maintains its position and changes in the position of the object, in particular its angular position in the circumferential direction, inevitably in dependence Course of the second curve 60 and are possible only in dependence on the course of this curve.

It has already been mentioned that with triple printing and use of all printing stations, the throughput of the machine with respect to the number of objects per unit of time is twice as large as with sixfold printing. As a result, twice as many objects must be taken out of the machine in the removal station and twice as many objects must be fed into the feed station of the machine. Since twice the number of objects has to be handled per time unit, The two transfer devices 22 and 30 must be adapted accordingly at the same rotational speed of the transfer devices and the annular disc 14. In the embodiment shown in the drawing (see Fig. 2), the transfer stations are formed so that the respective plate 24 can be provided near its periphery with six grippers 26. This number of grippers is required when the second of the above-described operating possibilities is used, in which the objects are led out of the printing press after one pass and three times printing. In the other case, ie with sixfold Bedrukkung and therefore half throughput, each plate 24 would be equipped with three grippers, the rotational speed of the plate 24 is the same in both cases.

In the case of only one pass of the objects, the two carriers are permanently set according to the illustration of FIG. 1 so that the cam roller 42 controlling the upper holding part 34 always passes through the upper curve section 62 between the two carriers 72, 74, since each holder protrudes the sampling station must be opened and closed after the feed station.

FIGS. 2A and 2B show that the toothed segments 52 of the individual holders 16 are dimensioned so that the paths of movement of the toothed segments 52 of two directly adjacent holders 16 overlap one another. For this reason, it may be necessary to arrange the tooth segments 52 of adjacent holders in height offset from each other, so as to achieve a mobility of the tooth segments, which is not limited by the presence of adjacent tooth segments.

The gear 50 for transmitting the movement to the respective toothed segment 52, regardless of the diameter of the surface to be printed of the respective object have the same diameter, so that there is no need, the To replace gears 50 of the brackets, if given a change from one lot to be imprinted objects on another lot another object diameter. Changes in the diameters of the objects can be compensated with unchanged diameter of the gear 50 that during the printing process, the screen stencil are compensated either in the direction of movement of the object in the transport direction 12 or opposite thereto, said movement of the template substantially tangential to the circular transport path can be done, which is determined by the annular disc 14.

Due to the fact that the object also moves during the printing on a circular path, it may be necessary during printing to adjust the position of the screen printing stencil 89 to that of the object. Thus, the angular position of the substantially vertically extending template can be adapted to the position of the object to be printed, as described for example in US-PS 4,798,135. Another possibility is to move the screen printing stencil during printing to the center of the machine fulcrum so as to compensate for the changing distance of the jacket surface of the object to be printed on the screen printing stencil arranged tangentially to the transport path. But it is also possible to use a slightly curved template, wherein the template is arranged approximately coaxially to the transport path along which the objects are moved. Moreover, there is the possibility already mentioned, by means of a certain elastic deformation of the template by appropriate positioning of the associated doctor blade to bring the template into contact and out of contact with the object to be printed and so to influence the printing process and the relative position of the doctor blade to the object and to control.

The two transfer devices 22 and 30 are, as already mentioned, provided with a plurality of gripper systems, which are designed so that when entering or removing the object, a match of the positions of the gripper on the one hand and the holder on the continuously rotating annular disc on the other. This can be achieved in that each gripper performs additional movements relative to the plate 24 carrying it, in order, on the one hand, to have the time to insert the object vertically into the respective holder or to lift it out by a vertical movement. However, as already mentioned, other transfer devices can also be used in order to input or remove the objects from the holders 16.

When an embodiment of twenty-seven pickups, six printing stations, and three drying stations is described above, it is not intended to be limiting. Rather, it is readily possible to provide the printing machine with, for example, four printing stations and two drying stations, which are then arranged in a corresponding manner, ie one drying station in the transport direction behind two printing stations, wherein the odd number of shots may be, for example, twenty-one.

Claims (16)

1. Apparatus for printing on dimensionally stable individual articles (18), wherein the apparatus is provided with a continuously circulating transport device (14) for transporting the articles (18) carried by a respective holder (16) along a transport path with which there are associated at least one treatment station (I, II, III, IV, V, VI; A, B, C) and at least two transfer stations (22, 30) of which one is in the form of a feed station in which the articles to be printed upon are put on or in the holders (16) disposed at the transfer device (14), and the other is in the form of a removal station in which the printed articles are removed from the holders (16) of the transport device, characterised in that during the printing operation the article (18) is rotated about its longitudinal axis in a first direction determined by the printing procedure and the transport direction and after termination of the printing procedure the article is rotated back into its initial position by rotation about its longitudinal axis in an opposite second direction.
2. Apparatus according to claim 1 characterised in that the articles (18) do not experience any rotation about their longitudinal axis in the transfer stations (22, 30).
3. Apparatus according to claim 1 characterised in that the articles (18) assume in the holder (16) a position in which their longitudinal axis extends substantially vertically.
4. Apparatus according to claim 1 characterised in that the holders (16) for the articles to be decorated on the transport device (14) are of a two-part configuration such that the article (18) is inserted at its lower end in a holder portion (32) in the form of a receiving means and is held at its upper end by a holder portion (34) which is reciprocatable between a position in which it is in engagement with the article and holds it in its position in the holder (18) and a position in which it is out of engagement with the article.
5. Apparatus according to claim 1 characterised in that the lower receiving means (32) of the holder for the articles is connected to a gear (50) which is coaxial with respect to the longitudinal axis thereof and which is drivable by a rotatably supported element (52) which is provided with a corresponding tooth arrangement and which in turn is provided with a cam roller (58) which is arranged at a spacing from its axis of rotation (54) and which is in engagement with a cam (60) mounted to the machine frame structure, and the rotary movement of the lower receiving portion (32) is determined by the configuration of said cam (60).
6. Apparatus according to claim 5 characterised in that the cam (60) is endless.
7. Apparatus according to claim 5 characterised in that the cam (60) extends substantially parallel to the transport path at least in the region of the transfer stations (22, 30).
8. Apparatus according to claim 5 characterised in that the diameter of the gear (50) is independent of the diameter of the articles (18) to be printed upon and relative adaptation of the peripheral speed of the surface of the article which is to be printed upon to the transport speed is effected by suitably setting the speed at which the screen printing stencil (89) is moved.
9. Apparatus according to claim 4 characterised in that provided in each transfer station (22, 30) is a transport element (24) which circulates continuously in a horizontal plane and which carries grippers (26), by means of which the articles (18) to be printed upon are introduced into the respective holder (16) or the printed articles are removed from the respective holder.
10. Apparatus according to claim 9 characterised in that the grippers (26) are mounted movably upwardly and downwardly on the respective transport element (24) and the articles to be printed upon are fitted into the receiving means (32) of the holder (16) by means of a downward movement of the respective gripper (26) and the printed article is removed from the receiving means (32) by means of an upward movement of the respective gripper (26).
11. Apparatus in particular according to claim 1 characterised in that the transport device (14) is provided with an odd number of holders (16) for the articles (18) and provided in the transport direction (12) downstream of at least two respective printing stations (I, II; III, IV; V, VI) is a respective drying station (A, B, C) and on each passage of the articles (18) through the transport path printing is effected only in one of the at least two screen printing stations disposed upstream of the common drying station and the printing stations in which an article is printed upon during a circulating pass are at a spacing from each other which is an even multiple of the spacing of two adjacent receiving means (32) in the transport direction and the spacing between two printing stations which are provided upstream of a common drying station in the transport direction is an odd multiple of the spacing of two adjacent receiving means (32).
12. Apparatus according to claim 9 characterised in that the article (18) performs as many passes through the transport path (18) as there are printing stations (I - VI) between two drying stations (A, B, C) and in each pass is printed upon in another of said printing stations.
13. Apparatus according to claim 9 characterised in that the article (18) is respectively printed upon only in one of the screen printing stations (I - VI) disposed upstream of a common drying station (A - C) and after a pass is removed from the apparatus.
14. Apparatus according to claim 9 characterised in that a total of six screen printing stations (I - VI) are arranged along the transport path and the article (18) for carrying out six printing operations which are performed in succession on the same article is moved a total of twice past the screen printing stations and is printed upon in each case only in one of the two screen printing stations arranged upstream of a common drying station (A, B, C).
15. Apparatus according to claim 4 characterised in that the upper upwardly and downwardly movable holder portion (34) is provided with an extension portion which is in engagement with a cam (46) provided on the machine frame structure and the position of the holder portion (34) during transport along the transport path is dependent on the configuration of the cam (46).
16. Apparatus according to claim 13 characterised in that disposed in the region of the transfer stations are two cam portions (44, 62) for positioning of the upper holder portion (34), of which the one (44) produces the closed position of the upper holder portion (34) and the other (62) produces the open position thereof and both cam portions (44, 62) are alternatively operative or inoperative in dependence on whether the printed article (18) which in the transport path is approaching the removal station is removed in the removal station by the transfer device or is removed only after at least one further pass along the transport path.

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