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瓦楞纸机和旋转印刷机英文文献和中文翻译(3)

时间:2020-09-26 16:23来源:毕业论文
The carrier bands may themselves be constructed as printing forms, and the carrier bands may either extend over the full width of the paper web or else the carrier bands may extend over only a part of

The carrier bands may themselves be constructed as printing forms, and the carrier bands may either extend over the full width of the paper web or else the carrier bands may extend over only a part of the width of the paper web, as it is described with reference to the second embodiment. In both cases the actual surface area portions which participate in the printing, extend only over a part of the width of the paper web, unless in a specific special case several identical patterns are arranged adjacent one another .The carrier bands assure that a printing station can be changed over in the briefest possible time, because only the carrier band must be exchanged. The tension rollers at the printing station must then be readjusted for the possibly different loop-length of the carrier band. This is also possible in the shortest amount of time. The printing stations are provided approximately corresponding to double, triple or a multiple the number of patterns. Advantageous appears the arrangement of approximately twenty printing stations for a width of the paper web of approximately 2.5 m. At this width and with the 35 stated number of printing stations it is possible to work with three or even four pattern areas of different printed pictures adjacent one another. It is understood that only one part of the printing stations is used for the production run being printed at any moment, with each printing station printing only a one color and in the event of multi-color printing several colors being applied per pattern area by different printing stations in sequence ,The other printing stations can be changed over in this time period and are then available for printing the next 45 successive run or order. If a printing order is completed , then it is only necessary to switch off the corresponding printing stations; the new printing stations are switched on. This is effected without interrupting the manufacture of the corrugated- paper.

In doing so, the following difficulty occurs.

In the integration of the special printing stations with the carrier bands carrying the printing forms a peculiar- ity occurs, in contradistinction to normal rotary printing machines which work with printing cylinders of different diameters. The carrier bands which carry the printing forms do not rest on the circumference of the printing cylinders, but are guided in form of a loop and supported on supporting and tension rollers. The actual printing cylinder carries no printing forms but serves 60 only to press and guide the carrier band.

In these special printing stations which are integrated according to the invention there is no association be- tween the angular speed of the printing cylinder and the angular speed of the carrier band. While the carrier band has the same circumferential speed on the printing cylinder as the printing cylinder itself, it is not possible to arrive here at a relationship between the angular speed of the carrier band  and the angular speed of the printing cylinder.

This is in contrast to a normal rotary printing ma chine in which the printing forms are on the circumference of the printing cylinder. There, it is always possible to determine that after a complete revolution of the printing cylinder the printing form begins again with certainty, respectively that the identical portion is used for printing. Because this specific association is missing in the printing stations integrated according to the present invention, a relative rapport between the inpidual printing stations must be achieved in a different manner. This relative rapport is, of course, necessary only for those printing stations which must print one over the other with pattern rapport in a printing order.

     This will be explained by way of an example in more detail. While the corrugated paper machine operates and for example a certain number of printing stations is in printing operation, it is assumed that the printing stations No. 1, No. 5 and No. 7 in a row of 10 printing stations are standing still, so that they can be switched over for the next following printing order requiring a three-color print. 瓦楞纸机和旋转印刷机英文文献和中文翻译(3):http://www.youerw.com/fanyi/lunwen_61831.html

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