The present invention relates to a spacer sleeve for printing-press cylinders of variable-format printing presses.
Spacer sleeves are used in variable-format printing presses to compensate for a change, with printing-press cylinders which remain the same, in the diameter of the printing formes or rubber blankets which results during the format change. Here, the spacer sleeves are pushed onto the respective printing-press cylinder and serve as a carrier for, printing plates or printing sleeves, or else rubber blankets or rubber sleeves.
According to the prior art, spacer sleeves are manufactured from non-metallic materials for reasons of cost and weight. However, spacer sleeves made from non-metallic materials of this type are not precise in terms of their shape and dimensions, with the result that they can be used only to a limited extent, in particular for offset printing. The spacer sleeves which are known from the prior art therefore have to be subjected to a grinding operation to provide the outer diameter of the spacer sleeves with a precise shape and dimensions. Overall, this is a disadvantage.
An object of the present invention is to provide a novel spacer sleeve for printing-press cylinders of, in particular, variable-format printing presses.
This object is met by a spacer sleeve having a first inner metallic carrier layer and a second outer metallic covering layer. At least one dimensionally stable intermediate layer is arranged between the first metallic carrier layer and the second metallic covering layer, the at least one intermediate layer determining, in particular, the thickness or wall thickness of the sleeve.
In the context of the present invention, a spacer sleeve for variable-format printing presses is proposed which comprises at least two metallic, sleeve-like or tubular layers, that is to say the first, inner metallic carrier layer and the second, outer metallic covering layer. At least one intermediate layer is positioned between the two sleeve-like, metallic layers. The thickness of the at least one intermediate layer determines the wall thickness of the spacer sleeve. That is, the first and second layers are made of a metallic sheet and the thickness of the at least one intermediate is dimensioned so that the diameter of the spacer sleeve is sized for a particular application. Spacer sleeves can be manufactured precisely in terms of their shape and dimensions with the aid of the present invention, with the result that they can be used, in particular,. for offset printing without any subsequent grinding treatment.
The at least one intermediate layer is advantageously connected fixedly to the inner metallic carrier layer and/or to the outer metallic covering layer.
The at least one dimensionally stable intermediate layer is preferably formed from a metallic or non-metallic material, in particular from a foamed material such as PU foam or metal foam.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.
In the drawings, wherein like reference characters denote similar elements throughout the several views:
The inner metallic carrier layer 11 delimits a hollow space 14, by means of which the spacer sleeve 10 can be pushed onto a printing-press cylinder. Accordingly, the inner metallic carrier layer 11 of the spacer sleeve 10 is in contact with the printing-press cylinder when the spacer sleeve is received on the printing press cylinder (the printing press cylinder is not shown in the Figures). The diameter and wall thickness of the spacer sleeve 10 is determined primarily by the thickness of the dimensionally stable intermediate layer 13.
In the embodiment in
In the exemplary embodiment from
In the embodiments shown in FIGS. 1 to 4, the spacer sleeves 10, 15 and 18 shown there all serve for the accommodation of a device which forms a functional surface and which can be released or removed without being destroyed. These devices may be printing formes, such as printing plates or printing sleeves, or ink transfer devices, such as rubber blankets or rubber sleeves. The spacer sleeves 10, 15 and 18 serve primarily to provide diameter compensation in the event of a format change on a printing press. As has been explained already, the thickness or wall thickness of the spacer sleeves is determined primarily via the dimensionally stable intermediate layers.
A common feature of all the spacer sleeves according to the present invention which are shown in FIGS. 1 to 5 is that they have two metallic layers, that is to say an inner metallic carrier layer and an outer metallic covering layer, at least one dimensionally stable intermediate layer being positioned between these two metallic layers. In the mounted state, the inner metallic carrier layer of the spacer sleeves is in contact with a printing-press cylinder. The outer metallic covering layer of the spacer sleeves serves for the accommodation of a device which forms a functional surface and which can be released or, as an alternative, it is also possible for a further functional layer to be applied non-releasably to the outer metallic covering layer.
It is to be pointed out that it is also possible to use the metallic covering layer of the spacer sleeves 10, 15 and 18 of the exemplary embodiments according to FIGS. 1 to 4 directly as a printing forme which can be erased and have images set on it again. The spacer sleeve then forms a printing forme for printing presses which operate according to the direct imaging principle. Printing presses of this type which operate according to the direct imaging principle are marketed by the applicant under the product name “DICOweb”.
Finally, it is to be pointed out that the metallic, sleeve-like layers 11 and 12 of the spacer sleeves are preferably formed from a welded metal sheet. The spacer sleeves according to the present invention can be used as paper guide rolls or can serve as carriers of coated rolls in an inking unit of the printing press.
Thus, while there have shown and described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Moreover, it should be recognized that structures and/or elements shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.
Number | Date | Country | Kind |
---|---|---|---|
10 2004 048 634.4 | Oct 2004 | DE | national |