Abstract:
A rotary embossing device, in particular for making Braille embossments, includes a drive shaft and at least one embossing tool disposed thereon. The embossing tool includes a roller body, a mounting system and a tool sleeve. The tool sleeve is mounted to the roller body by the mounting system. The mounting system includes at least one mounting ring disposed between the roller body and the tool sleeve. The at least one mounting ring is advantageously engaged with an adjustment device for rotating the at least one mounting ring to adjust the angular position of the tool sleeve. The mounting ring includes at least one elastomeric ring and the mounting system further includes an axially displaceable mounting cover for compressing the at least one elastomeric ring. Tool sleeves can therefore be easily and quickly mounted and adjusted.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the priority, under 35 U.S.C. §119, of German Patent Application DE 10 2013 001 247.3, filed Jan. 25, 2013; the prior application is herewith incorporated by reference in its entirety. 
       BACKGROUND OF THE INVENTION 
     Field of the Invention 
       [0002]    The invention relates to a rotary embossing device for embossing flat materials such as sheets, blanks, webs of paper, cardboard, plastics and composite materials. The rotary embossing device includes a drive shaft and at least one embossing tool disposed thereon. The embossing tool has a roller body, a mounting system and a tool sleeve. The tool sleeve is mounted to the roller body by the mounting system. 
         [0003]    Folding boxes are packages made of cardboard or corrugated board or, to a more limited extent, of plastics. Depending on their construction, glue is applied to one or more locations of such a folding box during the folding process. In general, folding boxes are produced from blanks. The blanks are usually cut out in a flat-bed or rotary die cutter. The blank needs to be folded along multiple lines and to be glued at least along one edge. The folded boxes are flat when they exit the folder-gluer and may be stacked in compact stacks or packaged in cardboard shipping boxes. The folding boxes may be erected and filled manually or automatically in a packing machine. 
         [0004]    In addition to the folds required to produce folding boxes, further crease lines are pre-folded in the folder-gluer as a preparation of the following production step. That is done to facilitate the erection and the subsequent filling of the box. 
         [0005]    If the folding boxes are used to package pharmaceuticals, it is mandatory for the name of the product to be written, for example embossed, onto the folding box in letters for the blind, also referred to as Braille letters. Such a requirement frequently also applies to blister packs, which also need to be embossed with Braille letters or other types of embossments. 
         [0006]    In accordance with the prior art, the Braille letters may be embossed during the die cutting process in the die cutting machine when the blanks are being produced. However, that is a laborious process since a sheet to be cut contains multiple blanks, and for each blank, a pair of tools formed of a male tool and a female tool needs to be provided. 
         [0007]    Alternatively, the embossment may be created in a rotary embossing device that includes two rotating embossing tools and may, for instance, be part of a folder-gluer. 
         [0008]    Known Braille embossing devices in general are formed of an upper rotary tool, the male braille tool, and a lower rotary tool, the female Braille tool. The male Braille tool has a defined number of raised Braille embossing dots on its embossing side. The female Braille tool in general has the maximum possible number of Braille dot depressions so that it is a universally usable tool. The number of depressions or cells depends on whether the Braille embossment to be applied is based on the common 6-dot system or on the 8-dot system. 
         [0009]    A plurality of different Braille embossments is necessary in particular for producing packaging for pharmaceuticals. For that purpose, the male Braille tool needs to be changed for every new job to be produced, requiring a plurality of male Braille tools to be kept in stock in a tool storage room. 
         [0010]    German Utility Model DE 20 2008 017 133 U1 discloses leaving the roller bodies unchanged and only changing the tool to reduce storage requirements. The tool is attached to the circumferential surface of the roller body by magnets and is held thereon during operation by magnetic force. 
         [0011]    German Patent Application DE 10 2010 036 011 A1, corresponding to U.S. Patent Application Publication No. 2012/0048131, discloses a tool for a rotary embossing device for embossing flat, sheet-shaped material. The device includes two rotating embossing tools in the form of a male tool and a female tool for creating the embossments. At least the male tool is formed of a roller body to which a continuous, annular tool sleeve or a slotted tool sleeve is attached. The tool sleeves are fixed by mounting systems that are described in detail. The male tool sleeve has raised embossment dots on its circumferential outer surface, in accordance with the job to be embossed. Those dots interact with corresponding depressions in the circumferential outer surface of the universal female tool. 
         [0012]    The disadvantages of mounting systems of that type include the fact that they have high mass inertial forces, which may result in imbalances, and that they are difficult to access by a machine operator, a fact which makes changing the embossment sleeve a complex and time-consuming process. 
         [0013]    A further disadvantage is that when two or more male embossing tools are mounted to the same drive shaft, relative synchronization between the two is impossible. However, for reasons of manufacturing tolerances, such synchronization is necessary to produce high-quality printed products. That is true in particular for meeting the legal requirements for embossing Braille letters for the blind. The prior art only discloses ways to synchronize the male embossing tool and the associated female embossing tool by rotating their drive shafts relative to each other. However, that method only allows both (or several) male embossing tools to be corrected by the same angular degree. 
       SUMMARY OF THE INVENTION 
       [0014]    It is accordingly an object of the invention to provide a rotary embossing device with a mounting system and an angular adjustment, which at least partly overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices of this general type and which allows easy mounting and adjustment of a tool sleeve. 
         [0015]    With the foregoing and other objects in view there is provided, in accordance with the invention, a rotary embossing device for embossing flat or planar materials such as sheets, blanks and webs of paper, cardboard, plastics and composite materials. The rotary embossing device of the invention comprises a drive shaft and an embossing tool disposed thereon, the embossing tool including a roller body, a mounting system, and a tool sleeve, which is mounted to the roller body by the mounting system. A rotary counter-tool may be mounted to a parallel further drive shaft. In order to process the planar material, the material is transported between the two tools. In accordance with the invention, the mounting system includes at least one mounting ring disposed between the roller body and the roller sleeve and used to mount the tool sleeve. In contrast to the mounting systems of the prior art, the mounting ring has a low mass moment of inertia. Advantageously, the at least one mounting ring is in engagement with an adjustment device for rotating the at least one mounting ring to adjust the angular position of the tool sleeve about an axis of rotation of the embossing tool. Thus, the tool sleeve is likewise rotated relative to the drive shaft. The rotation is attained by a displacement of the mounting ring along the roller body surface, which is preferably cylindrical. This feature provides adjustability of the angular position of the mounting ring and thus of the tool sleeve relative to the drive shaft and thus relative to a counter-tool that may potentially be provided. If multiple embossing tools are provided on one and the same drive shaft, it is possible for the tool sleeves of the embossing tools to experience different angular adjustments and thus to be adjusted relative to each other. 
         [0016]    In accordance with another particularly advantageous and thus preferred development of the rotary embossing device of the invention, the adjustment device in particular includes a positioning element that is movable in particular in an axial direction and is assigned an adjustment mechanism in particular disposed inside the roller body, and a groove is formed on the interior surface of the mounting ring, the positioning element being displaceable in the groove, with a displacement causing an adjustment of the mounting ring. The groove in the mounting ring is in particular aligned at an acute angle relative to the axial direction. The adjustment mechanism is easily accessible from outside the embossing tool, easily allowing the operator to adjust the mounting ring by actuating the adjustment mechanism. A further advantage is that the adjustment device has a very compact construction and has only a low moment of inertia. 
         [0017]    In accordance with a further alternative embodiment of the rotary embossing device of the invention, the adjustment device includes a cam disc that is supported in the roller body and the rotation of which causes the mounting ring to be adjusted. 
         [0018]    In accordance with an added alternative embodiment of the invention, the adjustment device includes a worm gear/spur gear system and the interior surface of the mounting ring has a toothing. A rotation of the worm gear is transmitted to the mounting ring by the spur gear and the toothing causes the mounting ring to be adjusted. 
         [0019]    With the objects of the invention in view, there is also provided a rotary embossing device, in particular a rotary embossing device constructed in accordance with the above description. In accordance with the invention, the mounting system includes a mounting ring disposed between the tool body and the tool sleeve to mount the tool sleeve. The mounting ring advantageously includes at least one elastomeric ring and the mounting system further includes a mounting cover that is axially movable to compress the at least one elastomeric ring. When the at least one elastomeric ring is compressed by the mounting cover, the at least one elastomeric ring expands in the radial direction, resulting in a mounting of the tool sleeve. This construction of the rotary embossing tool advantageously provides easy mounting of the tool sleeve, in that the tool sleeve may firstly be slid onto the mounting ring and then the tool sleeve is mounted by a rotation of the mounting cover and is thus fixed to the roller body. 
         [0020]    In accordance with another particularly advantageous and thus preferred development of the rotary device of the invention the mounting ring includes a plurality of elastomeric rings and in particular a respective stiff spacer ring between each two elastomeric rings. This allows the mounting force of the mounting system to be particularly evenly distributed and to act onto a large area of the tool sleeve to hold the tool sleeve in a particularly secure way. 
         [0021]    In accordance with a further advantageous development at least one end of the roller body has an exterior threading and the mounting cover has a complementary interior threading to screw the mounting cover onto the roller body, fixing the mounting ring on the roller body. At the same time, screwing on the mounting cover causes the mounting cover to be axially displaced and the elastomeric ring to be compressed. 
         [0022]    In accordance with an added feature of the invention, the elastomeric material may in particular be acrylonitrile butadiene rubber. 
         [0023]    In accordance with a first embodiment, the tool sleeve is tubular and has a continuous circumferential surface. In accordance with an alternative second embodiment, the tool sleeve is likewise tubular, but has a slotted circumferential surface. In the second case, in accordance with a particularly advantageous embodiment, the mounting ring includes a connecting piece and the two longitudinal edges of the tool sleeve are connectible to the connecting piece, in particular in a form-locking way. The elastomeric rings and spacer rings may be fixed to the connecting piece. The groove of the adjustment device may likewise be disposed in the connecting piece. A form-locking connection is one which connects two elements together due to the shape of the elements themselves, as opposed to a force-locking connection, which locks the elements together by force external to the elements. 
         [0024]    In accordance with a concomitant feature of the invention, the tool may advantageously be used in a Braille embossing device in a folder-gluer. 
         [0025]    Other features which are considered as characteristic for the invention are set forth in the appended claims, noting that any combination of the described invention and the described advantageous further developments of the invention also form an advantageous further development of the invention. Further advantages and embodiments that are advantageous in structural and functional terms are set forth in the dependent claims and the description of exemplary embodiments with reference to the appended figures. 
         [0026]    Although the invention is illustrated and described herein as embodied in a rotary embossing device with a mounting system and an angular adjustment, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. 
         [0027]    The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which corresponding elements and components are indicated by identical reference symbols and in which, for reasons of clarity, the figures are not drawn to scale. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         [0028]      FIG. 1  is a diagrammatic, perspective view of an embossing apparatus including an embossing device of the invention; 
           [0029]      FIG. 2  is an exploded, perspective view of the embossing device; 
           [0030]      FIG. 3  is an exploded, perspective view of an alternative embodiment of the embossing device; and 
           [0031]      FIGS. 4A and 4B  are perspective views of two alternative embodiments of an angle adjustment device. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0032]    Referring now to the figures of the drawings in detail and first, particularly, to  FIG. 1  thereof, there is seen an embossing apparatus that includes a rotary embossing device  1  constructed in accordance with the invention and shown in a partially disassembled condition. The rotary embossing device  1  includes an upper tool embodied as a male tool  2  and a lower tool embodied as a female tool  3 . The male tool  2  is formed of a roller body  4  to which a tool sleeve  5  is fixed. The tool sleeve  5  has raised embossing dots on its circumferential surface. For reasons of visibility, the raised dots are not shown in  FIG. 1 . The female tool  3  likewise includes a roller body  6 , having an outer circumferential surface  7  with corresponding depressions (which are likewise not shown in  FIG. 1  for reasons of clarity). The depressions may be formed either directly in the outer circumferential surface  7  of the roller body  6  of the female tool  3  or, in a manner analogous to the male tool, in a tool sleeve, which is not shown in any detail herein and which is fixed to the roller body  6  of the female tool  3 . Both the male tool  2  and the female tool  3  are protected against contact by protective boxes  8 ,  9 . The male tool  2  is supported on a (non-illustrated) flange and is driven by a drive shaft  12 . Furthermore, the male tool  2  is laterally guided by an upper tool-guiding element  10  that is supported on a crossbar  15 . The female tool  3  is supported on a (non-illustrated) flange and is driven by a lower drive shaft  13 . Furthermore, the female tool  3  is laterally guided by a lower tool-guiding element  11  that is supported on a lower crossbar  16 . Further rotary tools may be provided on the drive shafts  12 ,  13  in parallel with the illustrated rotary tools  2 ,  3 . A position of a further male tool  2 ′ is indicated by a first dot and a position of a further female tool  3 ′ is indicated by a second dot. The drive shafts  12 ,  13  are driven by servomotors  14 . An embossing device of this kind allows sheet-shaped, blank-shaped, or web-shaped printing substrates to be provided with an embossment, in particular a Braille embossment, by passing the printing substrates between the male tool  2  and the female tool  3  using a commonly known and thus non-illustrated belt transport system. 
         [0033]      FIG. 2  illustrates a rotary embossing device  1  of the invention that may be slid onto a diagrammatically-illustrated drive shaft  12  and may be fixed to a diagrammatically-illustrated crossbar  15  by using a tool-guiding element  10 . A roller body  4  is supported on ball bearings  10 . 2  of a tool carrier  10 . 1  and has an internal polygon that has a complementary construction relative to an exterior polygon of the drive shaft  12 . Polygonal shafts or a shaft and a fitting key may be used instead of a polygon, in which case the roller body likewise has a complementary construction. Thus, the roller body  4  is supported on the tool carrier  10 . 1  and is driven by the drive shaft  12 . A mounting ring  31  is slid onto the roller body  4 . The mounting ring  31  is formed of a plurality of elastomeric rings  32 . A respective spacer ring  33  is disposed between every two elastomeric rings  32 . Both the elastomeric rings  32  and the spacer rings  33  are fixed to a connecting piece  34  and are held together in this way. One end of the roller body  4  is provided with an exterior threading  38 , onto which a mounting cover  36  provided with an interior threading  37  may be screwed. Engagement locations for a tool may be provided in the mounting cover  36  to allow the mounting cover  36  to be easily rotated. These engagement locations may be bores for a face pin spanner wrench. When the mounting cover  36  is screwed on, the mounting ring  31  is secured. 
         [0034]    This device is used to receive job-dependent tool sleeves  17  having different structures which may, for instance, be provided with raised portions to create Braille dots. In the illustrated case, the tool sleeve is a slotted tool sleeve  17 . This tool sleeve  17  may be slid onto the mounting ring  31  without difficulty. The longitudinal edges of the tool sleeve  17  in the region of its slot engage in specifically formed grooves of the connecting piece  34 , causing the tool sleeve  17  to be fixed on the mounting ring  31 . In order to ensure a secure fit of the tool sleeve  17 , tension needs to be created in the mounting system  30 . This is done by screwing the mounting cover  36  further onto the roller body  4 . This screwing movement causes the elastomeric rings  32  to be compressed or squeezed and to expand in a radial direction. Due to the expansion of the elastomeric rings  32 , the tool sleeve  17  is mounted and is securely pressure-fitted onto the roller body  4 . A screwing movement s for mounting purposes is indicated by a double-headed arrow in  FIG. 2 . 
         [0035]    If an angular adjustment of the tool sleeve  17  needs to be made relative to a non-illustrated counter-tool or relative to a (non-illustrated) further rotary embossing tool  2  mounted to the shaft  12 , the angular adjustment may easily be achieved by actuating the adjustment device  20 . For this purpose, the adjustment device  20  includes a positioning element  21 , which is pin-shaped and may be actuated by an adjustment mechanism  23 . The adjustment mechanism  23  includes a threaded pin that has a hexagonal socket, for example, which is easily accessible from outside of the male tool  2 . Actuation of the hexagonal socket causes the headless screw to be rotated. The positioning element  21  has a matching interior threading and is displaced in an axial direction by the rotation. The adjustment mechanism  23  is integrated in the roller body  4 . Only a pin of the positioning element  21  protrudes from the offset circumferential surface of the roller body  4 . This pin of the positioning element  21  engages in a groove  22  formed on the interior side of the connecting element  34 . A groove  22  (indicated by a dashed line in  FIG. 2 ) is oriented in the connecting element  34  in such a way that it is aligned at an acute angle relative to the axial direction. Thus, an axial displacement of the positioning element  21  due to an actuation of the adjustment mechanism  23  results in an angular adjustment of the connecting element  34  and thus of the entire mounting ring  31  together with the entire tool sleeve  17 . In order to illustrate this aspect, the orientation of the groove  22  is indicated by a dashed line in  FIG. 2 . A resultant adjustment movement j in the circumferential direction of the tool sleeve  17  to correct the angular position of the tool sleeve  17  is indicated by an arrow. 
         [0036]      FIG. 3  illustrates an alternative embodiment of the rotary embossing device  1  for using continuous tool sleeves  18 . The continuous tool sleeve  18  has a recess  19  on its circular edges. The connecting piece  34 , which is connected to the mounting ring  31  and inserted between the roller body  4  and the mounting ring  31 , has a protrusion  35  that is complementary to the recess  19 . When the tool sleeve  18  is slid onto the mounting ring  31 , the recess  19  engages in the protrusion  35  so that the continuous tool sleeve  18  is fixed to the tensioning ring  31 . The mounting of the tool sleeve  18  is achieved in the way described above, i.e. by a further screwing-on(s) of the mounting cover  36 . The angular adjustment of the tool sleeve  18  may likewise be achieved with the aid of an adjustment device  20  as described above, which causes the connecting piece  34 , the mounting ring  31  and thus the tool sleeve  18  to rotate in a circumferential direction by using a groove (indicated by a dashed line). 
         [0037]      FIG. 4A  illustrates a first alternative embodiment of the adjustment device  20 . The adjustment device  20  has a worm gear/spur gear system  25 ,  26 . The worm gear  25  is provided with a hexagonal socket, which is easily accessible from outside through a bore in the connecting piece  34 . The worm gear  25  engages in a spur gear  26  that is provided with an exterior toothing. The exterior toothing of the spur gear  26  in turn engages in a toothing  27  on the inside of the connecting piece  34 . The interaction between the worm gear  25  and the spur gear  26  results in a very high degree of gear reduction and thus in a very accurate adjustment of the position of the connecting piece  34  relative to the roller body  4 . 
         [0038]      FIG. 4B  illustrates a further alternative embodiment of the adjustment device  20  including a cam  24 . The cam  24  is inserted in the roller body  4  and is supported for rotation by a journal  28  that engages in a bore in the roller body  4 . The cam  24  has a hexagonal socket on its surface which is not visible in  FIG. 4B , for initiating a rotary movement of the cam disc  24  from outside the rotary embossing device  1 . The cam disc  24  is located in the region of a connecting piece  34 . For this purpose, the connecting piece  34  has a groove  39  on its interior side for receiving the cam disc  24 . A longitudinal bore  39 . 1 , which is only visible in outline in  FIG. 4B , is formed in the region of the groove  39  in the connecting piece  34 . The longitudinal bore  39 . 1  ensures that the (non-illustrated) hexagonal socket of the cam disc  24  remains accessible to the operator of the machine. Rotation of the cam disc  24  causes the connecting piece  34  to be displaced relative to the roller body  4  through the groove  39 , resulting in an angular adjustment of the mounting ring  31  and thus of a tool sleeve  17 ,  18 .