VACUUM CYLINDER UNIT FOR TRANSFERRING LABELS

Abstract

The invention relates to a vacuum cylinder unit for transferring labels to containers in a vacuum-supported manner, and a labeling device equipped with said unit. The vacuum cylinder unit comprises a drive shaft and a vacuum cylinder which is coupled thereto in a centered and driving manner by means of a zero-point clamping system. Because the zero-point clamping system comprises a clamping pin which is integrated into the vacuum cylinder and a clamping chuck which is rigidly connected to the drive shaft for securing the clamping pin, the vacuum cylinder can be manually lifted off the drive shaft by a small vertical stroke and the majority of the weight of the zero-point clamping system can be moved into the region of the drive shaft. This also reduces the amount of equipment needed for the vacuum cylinder which is designed as a format-specific interchangeable part.

Claims

1. A vacuum cylinder unit for transferring labels to containers in a vacuum-supported manner in a labeling device for containers, the vacuum cylinder unit comprising: a drive shaft; and a vacuum cylinder coupled to the drive shaft in a centered and driving manner by a zero-point clamping system, wherein the zero-point clamping system comprises; a clamping pin integrated into the vacuum cylinder; and a clamping chuck, wherein the clamping chuck is rigidly connected to the drive shaft for securing the clamping pin.

2. The vacuum cylinder unit of claim 1, wherein the clamping chuck comprises a spring-loaded pretensioned locking mechanism which can be pneumatically opened.

3. The vacuum cylinder unit of claim 2, further comprising a stationary lower part in which a compressed air duct is formed for supplying compressed air and a groove open at a top of the stationary lower part is formed with a coupling element that can be moved vertically therein, wherein the coupling element is formed such that with no supply of compressed air it lies in the groove with no contact with any components that are rotating in working mode and when the compressed air is supplied it is lifted off the groove such that it docks at a pneumatic connection for the clamping chuck to the pneumatic opening thereof.

4. The vacuum cylinder unit of claim 3, wherein the coupling element and the groove on an input side in this respect run around an entire circumference of an axis of rotation of the vacuum cylinder in an annular shape in order to connect the clamping chuck to the compressed air duct independently of a rotational position of the vacuum cylinder relative to a base frame.

5. The vacuum cylinder unit of claim 4, wherein an output-side groove that is open at a bottom of the output-side groove is formed on an underside of a support plate which is rigidly connected to the clamping chuck and at which the coupling element can dock when the compressed air is supplied in order to produce the pneumatic connection to the clamping chuck via the output-side groove.

6. The vacuum cylinder unit of claim 5, wherein the output-side groove is designed to be annularly formed about the axis of rotation of the vacuum cylinder over the entire circumference.

7. The vacuum cylinder unit of claim 1, further comprising an external compressed air connection for supplying compressed air by a pressure hose.

8. The vacuum cylinder unit of claim 5, wherein indexing holes and/or indexing pins circumferentially surrounding the clamping pin are formed on the vacuum cylinder for specifying a relative rotational position of the vacuum cylinder relative to the drive shaft.

9. The vacuum cylinder unit of claim 2, wherein the clamping chuck is designed for the pneumatic opening of the zero-point clamping system by application of compressed air at a pressure of 4-8 bar.

10. The vacuum cylinder unit of claim 9, wherein the clamping chuck further comprises an opening mechanism for a forced opening of the zero-point clamping system when the compressed air is not being applied.

11. The vacuum cylinder unit of claim 1, wherein the clamping pin has an engagement length of 10 to 50 mm relative to the clamping chuck.

12. A labeling device for containers, the labeling device comprising: a vacuum cylinder unit, which unit is arranged for directly transferring labels to the containers.

13. The labeling device of claim 12, which is designed to transfer labels provided from rolls and coated with hot-melt adhesive.

14. A labeling machine comprising the labeling device of claim 13 and comprising a continuously rotatable container carousel for positioning the containers during the label transfer.

15. A labeling machine comprising the labeling device of claim 12 and comprising a continuously rotatable container carousel for positioning the containers during the label transfer.

16. The vacuum cylinder unit of claim 1, further comprising a stationary lower part in which a compressed air duct is formed for supplying compressed air and a groove open at a top of the stationary lower part is formed with a coupling element that can be moved vertically therein, wherein the coupling element is formed such that with no supply of compressed air it lies in the groove with no contact with any components that are rotating in working mode and when the compressed air is supplied it is lifted off the groove such that it docks at a pneumatic connection for the clamping chuck to a pneumatic opening thereof.

17. The vacuum cylinder unit of claim 16, wherein an output-side groove that is open at a bottom of the output-side groove is formed on an underside of a support plate which is rigidly connected to the clamping chuck and at which the coupling element can dock when the compressed air is supplied in order to produce the pneumatic connection to the clamping chuck via the output-side groove.

18. The vacuum cylinder unit of claim 17, wherein the output-side groove is annularly formed about an axis of rotation of the vacuum cylinder over an entire circumference of the axis of rotation.

19. The vacuum cylinder unit of claim 7, wherein the pressure hose has an air pressure gun connected thereto.

20. The vacuum cylinder unit of claim 1, wherein indexing holes and/or indexing pins circumferentially surrounding the clamping pin are formed on the vacuum cylinder for specifying a relative rotational position of the vacuum cylinder relative to the drive shaft.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] A preferred embodiment of the invention is illustrated in the drawing. In the figures:

[0028] FIG. 1 shows a section through the vacuum cylinder unit;

[0029] FIG. 2 shows a partial region of the vacuum cylinder unit when the coupling element is inactive;

[0030] FIG. 3 shows the partial region with docked coupling element; and

[0031] FIG. 4 is a schematic plan view of a labeling device.

DETAILED DESCRIPTION

[0032] As can be seen in FIG. 1, in a preferred embodiment the vacuum cylinder unit 1 comprises a drive shaft 2 and a vacuum cylinder 3, which are centered with respect to an axis of rotation 1a by means of a zero-point clamping system 4 and are coupled to one another so as to transmit torque.

[0033] The zero-point clamping system 4 comprises a clamping pin 5, which is fastened to the vacuum cylinder 3 and which points downwards during working operation, and a clamping chuck 6, which is rigidly connected to the drive shaft 2, for securing the clamping pin 5 by gripping it.

[0034] The clamping chuck 6 comprises a spring-loaded pretensioned locking mechanism 7 which can be pneumatically opened by applying compressed air 8, as is known, for example, from the System Zero Clamp?.

[0035] The vacuum cylinder unit 1 further comprises a stationary lower part 9 in which a compressed air duct 10 for supplying the compressed air 8 and a groove 11 open at the top toward the vacuum cylinder 3 is formed with a coupling element 12 which is vertically movable therein and is annularly formed around the entire circumference; see the representations detailed in this respect in FIGS. 2 and 3.

[0036] As can be seen in FIG. 2, the coupling element 12 is arranged in the groove 11 on the input side with respect to the compressed air supply in such a way that, without the compressed air 8 being applied to the input-side groove 11, it rests on the bottom 11a of the input-side groove 11 by the force of gravity and during working operation does not touch rotating components of the vacuum cylinder unit 1 arranged above it.

[0037] As shown in FIG. 3, the coupling element 12 is designed in such a way that, when compressed air 8 is applied to the input-side groove 11, it is lifted to such an extent that the coupling element 12 produces a pneumatic connection from the input-side groove 11 to a groove 13 arranged above the coupling element 12 and on the output side in relation thereto.

[0038] The output-side groove 13 is formed in a support plate 14 that is downwardly open, which plate is rigidly and permanently connected to the clamping chuck. The support plate 14 is also rigidly connected to the drive shaft 2 and consequently rotates during the working operation of the vacuum cylinder unit 1.

[0039] The compressed air 8 is supplied only when the vacuum cylinder unit 1 is stationary, so that the coupling element 12 can pneumatically dock at the then non-rotating support plate 14. In unpressurized working operation, the coupling element 12 in this respect rests against the bottom of the groove 11 and then does not touch the support plate 14.

[0040] In the support plate 14, at least one connecting line 15 (indicated only schematically) is formed between the output-side groove 13 and a compressed air connection (not shown) of the clamping chuck 6. Accordingly, the compressed air 8 applied to the input-side groove 11 can reach the clamping chuck 6 via the coupling element 12, the output-side groove 13 and the connection duct 15 in order to pneumatically open it.

[0041] In the coupling element 12, suitable grooves and/or holes (in each case not shown) could be formed, which on the one hand offer sufficient flow resistance to the compressed air 8 to lift the coupling element 12 and on the other hand enable sufficient passage of the compressed air 8 from the input-side groove 11 into the output-side groove 13 to pneumatically open the clamping chuck 6.

[0042] The input-side and output-side grooves 11, 13 and the coupling element 12 between them are preferably in each case annular in shape in order to enable the clamping chuck 6 to be acted upon with the compressed air 8 even independently of the rotational position of the support plate 14 and the vacuum cylinder 3 still coupled thereto with respect to the base frame 9. That is to say, the vacuum cylinder 3 can be pulled off upwards in any rotational position relative to the base frame 9 with a suitable application of compressed air to the clamping chuck 6. This enables an ergonomic handling of the vacuum cylinder 3 during format-specific replacement.

[0043] In principle, however, it would also be conceivable to form the input-side groove 11, the output-side groove 13 and/or the coupling ring 12 arranged therebetween only partially circumferentially or over a certain machine angle range (not shown), which is why the support plate 14 with the vacuum cylinder 3 must then be brought first into a rotary position suitable for the mutual alignment of the grooves 11, 13 relative to the base frame 9, before the compressed air 8 can be applied and the clamping chuck 6 can thereby be opened.

[0044] For supplying the compressed air 8, the support frame 9 preferably comprises an external compressed air connection 16 to which, for example, a compressed air hose (not shown) can be connected. For example, an air pressure gun or similar valve could be present on the pressure hose in order to manually trigger and terminate again the temporary supply of the compressed air 8.

[0045] As indicated in FIG. 1, indexing pins and/or indexing holes 17 surrounding the clamping pin 5 can be present in the region of the zero-point clamping system 4, for example on the vacuum cylinder 3, in order to fix the rotational position of the vacuum cylinder 3 relative to the drive shaft 2. In the region of the clamping chuck 6, corresponding openings and/or pins are thereby provided. This indexing then serves only to fix the relative rotational positions relative to one another, while the torque transmission between drive shaft 2 and vacuum cylinder 3 is effected by the zero-point clamping system 4, i.e., the force-fitting connection between clamping pin 5 and clamping chuck 6.

[0046] The zero-point clamping system 4 preferably automatically closes by means of spring pretensioning, but could in principle additionally be tightened mechanically. For separating and putting together the zero-point clamping system 4, said system is pneumatically opened, for example by applying an air pressure of 4 to 8 bar to the input-side groove 11. By pressure relief, the zero-point clamping system 4 locks in a centering and force-fitting manner by itself and remains permanently locked without the renewed application of pressure.

[0047] Preferably, the clamping chuck 6 further comprises an opening mechanism for the forced opening (not shown) of the zero-point clamping system 4 in the absence of an application of compressed air suitable for this purpose. As a result, the vacuum cylinder 3 can even be replaced if the compressed air 8 is not available.

[0048] The clamping pin 5 preferably has an engagement length 18 to be overcome during lifting of at most 50 mm with respect to the clamping chuck 6 in order to enable an ergonomic replacement of the vacuum cylinder 3.

[0049] For the sake of completeness, it should also be mentioned that suction elements 19 known in principle on the vacuum cylinder 3 are arranged uniformly distributed for receiving/dispensing labels.

[0050] FIG. 4 shows, by way of example and schematically, a labeling device 21 for labeling containers 22 (only one shown), In particular bottles, with which, for the direct transfer of labels 23 (only one shown) to the containers 22, the vacuum cylinder unit 1 is arranged with an exchangeable vacuum cylinder 3.

[0051] The labels 23 are provided, for example, from rolls 24 and coated by a gluing unit 25 with hot-melt adhesive. The labeling device 21 shown is thus preferably a hot-adhesive labeling assembly.

[0052] Alternatively, a corresponding coupling of a vacuum cylinder unit 1, but also in the case of a cold-adhesive labeling assembly (not shown), would be conceivable, and/or, in the case of gripper cylinders, transfer cylinders or the like, rotating units which would have to be replaced in their entirety on labeling devices in a format-dependent manner.

[0053] The labeling device 21 is then preferably a component of a labeling machine 31 which comprises a continuously rotatable container carousel 32 for positioning the containers 22 during the label transfer, and at least one labeling device 21 docked in a manner known in principle at the periphery of the container carousel 32.

[0054] The described arrangement of the zero-point clamping system 4 with clamping pin 5 arranged on the vacuum cylinder 3 and with clamping chuck 6 arranged on the drive shaft 2 enables an ergonomic replacement of the vacuum cylinder 3 in the event of format changes and also reduces the costs for the individual vacuum cylinders 3 to be kept available in a format-specific manner.

[0055] For the exchange of the vacuum cylinder 3, the motor connected to the drive shaft 2 is switched off and the vacuum cylinder unit 1 is brought to a standstill, i.e., without a running rotary drive.

[0056] As soon as the vacuum cylinder 3 is no longer rotating, the compressed air 8 can be applied, for example, at the external compressed air connection 16 and the coupling element 12 can thereby be lifted from the bottom of the groove 11 and docked to the output-side groove 13 located above it. As a result, the compressed air 8 flows via the input-side groove 11 and the coupling ring 13 into the output-side groove 13 and from there via at least one connection duct 15 to the clamping chuck 6.

[0057] The compressed air 8 applied there opens the clamping chuck 6 in such a way that the clamping pin 5 can be released and the vacuum cylinder 3 can be lifted upward from the drive shaft 2.

[0058] While compressed air 8 continues to be applied, a suitable vacuum cylinder 3 can be set in place for another label format by inserting its clamping pin 5 into the clamping chuck 6.

[0059] The clamping pin 5 is then mechanically secured in the clamping pin 6 by spring pretensioning and locked thereby in a torsionally rigid manner.

[0060] That is to say, when the clamping pin 5 is inserted into the clamping chuck 6, it is acted upon with the compressed air 8 and thus opened. By switching off the supply of compressed air, the clamping chuck 6 automatically closes around the clamping pin 5 by means of spring pretensioning.

[0061] For the correct assignment of the rotational position of the vacuum cylinder 3 to the drive shaft 2, indexing pins and/or indexing holes 17 present on the vacuum cylinder 3 are preferably brought into engagement with corresponding structures in the region of the clamping chuck 6. The torque required during working operation is then transferred by the force-fit of the zero-point clamping system 4 from the drive shaft 2 to the vacuum cylinder 3.

[0062] The absolute rotational position of the drive shaft 2/of the clamping chuck 6 can thereby be freely selected thanks to the pressure coupling over the full circumference on the coupling element 12.

[0063] After the zero-point clamping system 4 is closed by switching off the supply of compressed air, the vacuum cylinder unit 1 and the labeling device 21/labeling machine 31 associated therewith can resume working operation.

[0064] Although the present disclosure has been described with various embodiments, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as falling within the scope of the claims.

[0065] The present disclosure should not be read as implying that any particular element, step, or function is an essential element, step, or function that must be included in the scope of the claims. Moreover, the claims are not intended to invoke 35 U.S.C. ? 112(f) unless the exact words means for are followed by a participle.