US-12617576-B2 - Vacuum cylinder unit for transferring labels

US12617576B2US 12617576 B2US12617576 B2US 12617576B2US-12617576-B2

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.

Inventors

Christian Holzer
Gundolf Kipper

Assignees

KRONES AG

Dates

Publication Date: 20260505
Application Date: 20220414
Priority Date: 20210526

Claims (15)

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, and wherein the clamping chuck comprises a spring-loaded pretensioned locking mechanism which can be pneumatically opened.
2 . 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 the pneumatic opening thereof.
3 . The vacuum cylinder unit of claim 2 , wherein the coupling element and the groove on an input side 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.
4 . The vacuum cylinder unit of claim 3 , 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.
5 . The vacuum cylinder unit of claim 4 , wherein the output- side groove is annularly formed about the axis of rotation of the vacuum cylinder over the entire circumference.
6 . The vacuum cylinder unit of claim 1 , further comprising an external compressed air connection for supplying compressed air by a pressure hose.
7 . The vacuum cylinder unit of claim 4 , 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.
8 . The vacuum cylinder unit of claim 1 , 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.
9 . The vacuum cylinder unit of claim 8 , 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.
10 . 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, wherein the clamping pin has an engagement length of 10 to 50 mm relative to the clamping chuck.
11 . 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.
12 . The vacuum cylinder unit of claim 11 , 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.
13 . The vacuum cylinder unit of claim 12 , 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.
14 . The vacuum cylinder unit of claim 6 , wherein the pressure hose has an air pressure gun connected thereto.
15 . 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, 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

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a 371 National Stage of International Application No. PCT/EP2022/059999, filed Apr. 14, 2022, which claims priority to German Patent Application No. 102021113498.6, filed May 26, 2021, the disclosures of which are incorporated herein by reference. TECHNICAL FIELD The invention relates to a vacuum cylinder unit, and to a labeling device equipped with said unit for labeling containers. BACKGROUND Vacuum cylinder units are known components of labeling units for applying labels provided from rolls to containers, such as bottles, by means of hot-melt adhesive. The vacuum cylinder has the task here of transporting the labels provided with adhesive to the transport path of the containers in a vacuum-supported manner and transferring them to said containers. The vacuum cylinder is matched to the labels in a format-specific manner and for a format change can be pulled off upwards from the associated rotary drive. With regard to a torque transmission and good concentricity accuracy, a combination of a drive shaft with a polygonal cross-section and a correspondingly positive-locking hub on the vacuum cylinder has proven effective for this purpose. The polygonal shaft then extends substantially over the entire height of the vacuum cylinder, so that it has to be lifted off over the entire length of the polygonal connection during the format change and thus has to be pulled from the drive shaft. Due to the relatively high weight of the vacuum cylinder and the generally restricted access during changeover work, this procedure is very unfavorable from an ergonomic point of view. As a remedy, generic vacuum cylinder units have been proposed, for example in DE 10 2011 090 190 A1, DE 10 2013 212 132 A1 and DE 20 2013 103 475 U1, in which the polygonal shaft is replaced by a self-centering connection of a clamping pin to a clamping chuck. Such connections are also referred to as zero-point clamping systems. In the generic devices, the drive shaft has a comparatively short shaft stub at its upper end for this purpose, and the associated vacuum cylinder has a suitable clamping chuck which can be locked in a centering manner on the shaft stub. It is true that to remove the vacuum cylinder the distance to be overcome manually during the format change can thereby be reduced compared to devices having polygonal shafts. However, the clamping chuck and the associated actuating mechanism increase the weight of the vacuum cylinder, thereby partially nullifying the ergonomic advantages in the lifting of the vacuum cylinder. In addition, the clamping chuck and the associated actuating mechanism increase the amount of equipment needed for the vacuum cylinder designed as an interchangeable part, which increases the cost of its purchase to an undesired extent. The zero-point clamping systems of the generic vacuum cylinder units have therefore not yet become established, so that there is still a need to improve the ergonomics in the replacement of vacuum cylinders and thereby also to minimize as far as possible the costs for vacuum cylinders available in a format-specific manner. SUMMARY The stated object is achieved with a vacuum cylinder unit. Accordingly, said unit serves for vacuum-supported label transfer in a labeling device for containers and comprises a drive shaft and a vacuum cylinder coupled thereto in a centered and driving manner by means of a zero-point clamping system for transmitting torque. According to the invention, the zero-point clamping system comprises a clamping pin integrated into the vacuum cylinder and a clamping chuck connected to the drive shaft for securing the clamping pin. The clamping pin is the passive component in the zero-point clamping system, the clamping chuck is the actively closing/opening component. All components to be actuated for opening/closing the zero-point clamping system can thus be moved into the region of the drive shaft that is not to be exchanged during the format change. Consequently, the comparatively heavy and expensive clamping chuck with the associated actuating elements does not have to be lifted/replaced when the vacuum cylinder is being replaced, so that the ergonomics are improved and a comparatively favorable design of the vacuum cylinder becomes possible. In other words, the clamping pin arranged on the replaceable vacuum cylinder is comparatively lightweight and cost-effective. Suitable zero-point clamping systems are known, for example, under the name “Zero Clamp®” and generally comprise a clamping chuck housing made of hardened stainless steel, a steel cone for play-free clamping of the associated pin, an associated precision radial spring, a spring leaf, and preferably a locking mechanism, which closes by means of spring force and can be pneumatically opened. The clamping chuck preferably comprises a spring-loaded pretensioned locking mechanism which can be pneumatically opened, i.e., by applying compressed air. The