Printing unit

Abstract
A printing unit has at least four cylinders that form a printer. At least two of these four cylinders rotate independently of each other. At least one of the cylinders in the group of at least four cylinders has a set up rotational speed that is not zero and that is different from a production rotational speed of that cylinder.
Description




FIELD OF THE INVENTION




The present invention is directed to a printing unit The printing unit has at least four cylinders that form two pairs. Transfer cylinders of the two pairs cooperate in a print-on position.




BACKGROUND OF THE INVENTION




A four-cylinder printing unit is known from DE 196 03 663 A1. Two transfer cylinders which cooperate with each other are fixedly coupled to each other and can be selectively driven by the drive mechanism of one or of both associated forme cylinders, or via a transverse shaft which can be connected to the motors. In one mode of operation, one of the forme cylinders can be stopped for a plate change, while the associated transfer cylinder continues to run synchronously with the second forme cylinder.




EP 0 997 273 A2 discloses a mode of operation of a four-cylinder printing unit a forme cylinder is moved away from the remaining cooperating cylinders. In one example, the moved-away forme cylinder can be rotated by a drive motor, and in another example it can be rotated by an auxiliary motor.




A printing unit with two pairs of cylinders is known from EP 0 621 133 A1. Each of the cylinders of at least one pair has its own drive motor, which is independent of the remaining cylinders.




In accordance with the article “Digitaler Direktantrieb an Druckmaschinen” [Direct Digital Drive for Printing Presses], in Druckspiegel September 1999, cylinders and rollers can be separately controlled, for example in the course of independent change of several printing plates or while changing a rubber blanket, wherein the remaining units are stopped. It is also possible to operate each printing location, or printing group, independently of the others.




SUMMARY OF THE INVENTION




The object of the present invention is directed to providing a printing unit.




In accordance with the present invention, this object is attained by providing a printing unit with at least four cylinders that include a first pair with a first forme cylinder and a first transfer cylinder, as well as a second pair with a second forme cylinder and a second transfer cylinder. The two transfer cylinders cooperate in a print-on position. At least one of the transfer cylinders has a set-up rotational speed which differs from a production rotational speed and from zero. The associated forme cylinder also has a set-up rotational speed which differs from the production rotational speed and from a zero rotational speed.




The advantages which can be obtained by the present invention reside, in particular, in that a large operational diversity and variability of a printing unit or a cylinder assembly is created.




For example, it is possible in this way to move cylinders or groups of cylinders independently of each other at different rotational speeds, or also in different directions of revolutions, which may be required, for example, for a printing forme or for a rubber blanket change, when drawing in a paper web, or in the course of independent inking or washing of rollers and cylinders. In particular, different actions when setting up at set-up rotational speeds, or speeds different from the stop or zero rotational speed, or the production rotational speed for the individual cylinder types are therefore possible next to each other and with a paper web either running or stopped.




The simultaneous meeting of several different demands made on different components of a printing group or a printing unit is particularly advantageous by use of the printing unit in accordance with the present invention. For one, the operational modes contribute to time savings and therefore to a lowering of the production costs, and furthermore make possible the performance of various set-up operations at production speed or at draw-in speed of the running paper web. A flying plate change for single- or doubled-sided imprint operations is possible. For example, in advantageous operational states, a printing forme is changed or pre-inked, while the associated transfer cylinder continues to rotate at production speed. Washing, pre-inking or also a change of the dressing can take place.




An advantageous mode of operation of the printing unit, in the case of two pairs, each having a forme and a transfer cylinder, is the rotation of one of the forme cylinders at a setup rotational speed, while the remaining cylinders continue to rotate at production rotational speeds. Also, both transfer cylinders can be stopped or can rotate at a rotational speed for drawing in a paper web, or at production rotational speed while one of the forme cylinders, or both, are inked.




Variable operational modes are also provided, in an advantageous manner for four-cylinder printing units, and in particular for eight-cylinder printing units which are constituted by two four-cylinder printing units, in particular in respect to a flying plate change, or to an imprinter functionality. For example, the printing operation can be maintained, while one or several forme cylinders, whose rotational speed and also direction of rotation in part is different from the production rotational speed, are changed.




For example, a Y- or a lambda-shaped six-cylinder printing unit can be flexibly employed for a 2/1 print run, or also for a flying plate change, or for a imprint function during 1/1 printing, if one of the forme cylinders is operated at a rotation speed and in a direction of rotation for the change, while all of the remaining cylinders rotate at a production rotational speed. The transfer cylinder assigned to the forme cylinder to be changed is, for example, operated at the same time at a rotational speed and in a direction of rotation for washing, or for other set-up functions. This correspondingly also applies to a seven-, nine- or ten-cylinder printing unit.




For reasons of flexibility and of savings of time, as well as of waste, the operational states provided by the printing unit of the present invention are of great importance in the course of fitting prior to start-up, or at the end of the printing operation. For example, the forme cylinder and the transfer cylinder can simultaneously pass through different set-up programs.




The independent operation of the rollers for ink application, which are assigned to the forme cylinders, is also advantageous. For example, washing or pre-inking can take place regardless of the rotational speed and the direction of rotation of the forme cylinder and while the forme cylinder also passes through a set-up program.











BRIEF DESCRIPTION OF DRAWINGS




Preferred embodiments of the present invention are represented in the drawings and will be explained in greater detail in what follows.




Shown are in:





FIG. 1

, a schematic view of a forme and transfer cylinder of a printing group with an associated roller in accordance with the present invention,





FIG. 2

, a schematic view of a four-cylinder printing unit,





FIG. 3

, a schematic view of a six-cylinder printing unit,





FIG. 4

, a schematic view of an eight-cylinder printing unit,





FIG. 5

, a schematic view of a four-cylinder printing unit with the forme cylinder moved away, and in





FIG. 6

, a schematic side elevation view of a four-cylinder printing unit with two forme cylinders moved away.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




A printing unit of a printing press, in particular a rotary printing press, as shown in

FIG. 1

, has a first cylinder


01


, for example a forme cylinder


01


, and a second cylinder


02


cooperating with the forme cylinder


01


in a print-on position. The second cylinder


02


may be, for example, a first transfer cylinder


02


of a printing group


03


. The forme cylinder


01


can cooperate with an inking roller


04


, in particular an ink application roller


04


, a screen roller


04


, or an anilox roller


04


. In a print-on position, the transfer cylinder


02


cooperates with a web


06


, for example a web


06


of material to be imprinted, and in particular, a paper web


06


.




The forme cylinder


01


can be rotated independently of the transfer cylinder


02


, as a function of the operational state of the printing united. It can rotate at times at rotational speeds and/or directions of rotation which are different from the transfer cylinder


02


. The transfer cylinder


02


also rotates independently of the forme cylinder


01


at times.




In what follows, the operational states of the printing unit are defined by the rotational speed or by the effective circumferential speed on the surfaces, which are called “speeds” for short in what follows. The operational states mentioned by means of the term “rotational speed” are to be applied in the same way as the term “speed”.




The forme cylinder


01


can assume one, or several of the following operational states: it can be stopped, i.e. it rotates at a rotational speed “zero” NFZ. It can also rotate at a production rotational speed RFZ or a set-up rotational speed RFZ which, as a rule, is different from the stopped state NFZ and the production rotational speed PFZ.




The set-up rotational speed RFZ, in turn, can be a rotational speed DWFZ required for a change of the printing forme, a rotational speed VEFZ required for pre-inking, or a rotational speed WFZ required for washing. A further set-up rotational speed RFZ can also be a rotational speed TFFZ necessary for dry running, i.e. a speed necessary for accomplishing ink removal from the forme cylinder


01


on the web


06


, or a rotational speed EFZ for use in drawing in the web


06


. In the case of a direct image transfer to the surface of the forme cylinder


01


or onto the printing forme on the forme cylinder


01


, the set-up rotational speed RFZ can also represent a rotational speed BBFZ required for image transfer.




The transfer cylinder


02


can also selectively assume one or several of the following operational states. It can be stopped, so that it rotates at a rotational speed “zero” NÜZ, it can rotate at a production rotational speed PÜZ or a set-up rotational speed RÜZ, which, as a rule, is also different from both the NFZ and the production rotational speed PFZ. The set-up rotational speed RÜZ can again be a rotational speed AWÜZ for changing the dressing, a rotational speed EÜZ for drawing in a web


06


, a rotational speed WÜZ for washing, or a rotational speed VEÜZ for pre-inking the transfer cylinder


02


.




The production rotational speed PFC for the forme cylinder


01


lies, for example, between 20,000 and 50,000 revolutions per hour (r/h), and preferably between 35,000 to 45,000 r/h. The production rotational speed PÜZ of the transfer cylinder


02


also lies between 20,000 and 50,000 r/h, and preferably at 35,000 to 45,000 r/h.




The rotational speed VEFZ of the forme cylinder


01


characteristic for pre-inking, for example, lies in the range between 6,000 and 12,000 r/h.




The rotational speed VEÜZ of the transfer cylinder


02


lies, for example, between 6,000 and 12,000 r/h.




For washing the forme cylinder


01


, the rotational speed WFZ, for example, lies between 200 to 1,000 r/h, and in particular between 300 and 800 r/h, while the rotational speed WÜZ for washing the transfer cylinder


02


can lie between 300 and 40,000 r/h, for example, and in particular between 300 to 6,000 r/h.




The rotational speed EFZ, for example, of the forme cylinder


01


turning along for drawing in the web


06


lies between 600 and 2,000 r/h, for example, and in particular between 300 to 800 r/h, which approximately corresponds to a draw-in speed of the web


06


between 6 to 30 m/min, and in particular between 6 to 12 m/min.




The rotational speed EÜZ of the transfer cylinder


02


for drawing in the web


06


is, for example, 300 to 2,000 r/h, and in particular between 300 to 800 r/h, which rotational speed approximately corresponds to a draw-in speed of the web


06


between 6 to 30 m/min, and in particular between 6 to 12 m/min.




To accomplish an automatic change of a printing forme on the forme cylinder


01


, the rotational speed DWFZ of the forme cylinder


01


can lie between 300 r/h and 2,000 r/h, and in particular between 300 r/h and 1,000 r/h, wherein, as a rule, a reversal of the direction of rotation of the forme cylinder


01


also takes place during the changing process. However, the rotational speed DWFZ of the forme cylinder


01


can also lie between 120 and 300 r/h during a so-called tip operation. With a direct image transfer to the print forme or to the outer cylinder surface of the forme cylinder


01


, for example by use of laser diodes, the rotational speed BBFZ of the forme cylinder


01


as a rule lies above the production rotational speed PFZ, for example above 50,000 r/h, and in particular above 70,000 r/h for web-fed printing presses, and above 5,000 r/h, and in particular between 5,000 and 30,000 r/h, for sheet printing presses.




The rotational speed AWÜZ for changing the dressing or blanket on the transfer cylinder


02


lies between 300 and 2,000 r/h, and in particular between 300 and 1,000 r/h. If the change of the dressing is performed manually, which is preferred at present, the rotational speed of the transfer cylinder


02


can also lie between 120 and 1,000 r/h.




The rotational speed TFFZ of the forme cylinder


01


for dry running, such as required for ink removal from the forme cylinder


01


, lies between 2,000 and 4,000 r/h.




The rotational speeds for the forme cylinders


01


and for the transfer cylinders


02


preferably relate to cylinders


01


,


02


each of double circumference, i.e. to cylinders


01


,


02


on each of whose circumference two printing forms can be fastened, one behind the other in the circumferential direction of the cylinder. The circumferences for this are a function of the production format and lie, for example, between 900 mm and 1,300 mm. The rotational speeds of the forme cylinder


01


,


02


would have to be doubled in case of the use of cylinders


01


,


02


of single circumference. This correspondingly applies to printing groups


03


, wherein a forme cylinder


01


of single circumference cooperates with a transfer cylinder


02


of double or twice the circumference.




For one or for several of the rotational speed ranges of the forme cylinder


01


and the transfer cylinder


02


discussed above, either left or right directions of rotation are possible. These directions of rotation are defined in the subsequent drawing figures which depict side elevation views of the cylinders


01


,


02


.




The above-mentioned operational states, as well as the discussed preferred rotational speeds, should also be applied to further forme cylinders, transfer cylinders added in the course of the subsequent description.




The inking roller


04


, which is embodied as a screen or as an anilox roller


04


, or as a rubber-coated ink application roller


04


, can also either be stopped, so that it rotates at a rotational speed “zero” NW, or it can operate at a production rotational speed PW, or at a set-up rotational speed RW. The setup rotational speed RW can be a rotational speed VEW suitable for pre-inking, a rotational speed WW usable for washing, or a rotational speed WLW intended for the continued running of the inking roller


04


.




The preferred rotational speed ranges of the inking roller


04


are a function of the printing process and/or the configuration of the printing unit, or of the inking system.




In the following discussion, a differentiation is to be made between a simple rubber-coated ink application roller


04


, an anilox roller


04


or a screen roller


04


, as well as a screen roller


04


of twice the circumference. The inking roller


04


embodied as a simple rubber-coated ink application roller


04


preferably has approximately one-third the circumference of a forme cylinder


01


of double circumference. A screen roller


04


that is directly cooperating with the forme cylinder


01


, can have the circumference of a forme cylinder


01


of single circumference or, particularly in case of letterpress or flexographic printing, of a forme cylinder


01


of twice the circumference.




For example, the production rotational speed PW lies between 40,000 and 100,000 r/h for the anilox rollers


04


or for the screen rollers


04


of single circumference which are directly cooperating with the forme cylinder


01


, and between 60,000 and 150,000 r/h in the case of the ink application roller


04


. The production rotational speed PW of the screen roller


04


of twice the circumference lies between 20,000 and 50,000 r/h, for example.




The rotational speed VEW for pre-inking the inking roller


04


lies between 12,000 to 24,000 r/h, for example, in the case of the anilox roller


04


or the screen roller


04


being of single circumference, and between 18,000 and 36,000 r/h in the case of an ink application roller


04


.




For washing the inking roller


04


, the rotational speed WW, for example, lies between 600 and 1,600 r/h in the case of the anilox roller


04


or the screen roller


04


being of single circumference, and between 900 and 2,400 r/h in the case of an ink application roller


04


.




During continued running of the inking roller


04


, to counter any drying of the ink, the rotational speed WLW preferably lies between 3,000 and 6,000 r/h for a screen roller


04


of twice the circumference, between 6,000 and 12,000 r/h for a screen roller


04


of single circumference, and between 9,000 and 18,000 r/h for an ink application roller


04


.




As mentioned above, the operational states are also defined by effective circumferential speeds, or speeds for short, of the rotating bodies.




The production speed PFZ of the forme cylinder


01


lies between 6.4 and 16 m/s, for example, and in particular between 11 and 15 m/s. The same applies to the transfer cylinder


02


, if one is provided.




The speed PWFZ of the forme cylinder


01


, used for an automated changing of the printing forme, lies between 0.32 and 0.64 m/s, for example, and for a manual change, for example, lies between 0.10 and 0.32 m/s. For pre-inking the printing forme, the speed VEFZ of the forme cylinder


0


.


1


lies, for example, between 1.9 and 3.9 m/s, while for washing of the printing forme WFZ it lies between 0.06 and 0.32 m/s, for example, and in particular between 0.10 and 0.26 m/s. During dry running TFFZ of the printing forme, the speed of the forme cylinder


01


lies, for example, between 0.64 and 1.3 m/s. As a rule, the speed of the forme cylinder


01


for image transfer BBFZ is greater than 16 m/s, and in particular is greater than 22 m/s for web-fed printing presses, and for sheet-fed printing presses this speed is greater than 1.6 m/s, and lies, in particular, between 1.6 and 9.6 m/s. For drawing in the web


06


, the speed EFZ of the forme cylinder


01


lies, for example, between 0.10 and 0.50 m/s, and in particular lies between 0.10 and 0.2 m/s.




The same values, or ranges of values, are as advantageous for the transfer cylinder


02


as for the forme cylinder


01


for the respective operational states of pre-inking VEÜZ, for changing the dressing AWÜZ and for drawing in the web EÜZ. The speed AWÜZ of the transfer cylinder


02


for a manual changing of the dressing lies between 0.04 and 0.32 m/s. During washing WÜZ of the transfer cylinder


02


, its speed lies, for example, between 0.10 and 13 m/s, and in particular between 0.10 and 1.9 m/s.




The speeds of the inking roller


04


in the operational states where it is placed against the forme cylinder


01


are based on the speed of the latter, so that, for example, the production speed PW of the inking roller


04


also lies in the range between 6.4 and 16 m/s, and in particular between 11 and 15 m/s. If the inking roller


04


is embodied as a screen roller


04


, its circumference can then approximately correspond to the circumference of a forme cylinder


01


of single circumference, for example. If the circumference of the screen roller


04


has been selected to be greater, for example between 1.0 and 1.2 m, the above mentioned rotational speeds PW should be selected to be less. This correspondingly applies in the case in which the inking roller


04


is embodied as an ink application roller


04


. The rotational speed to be selected is again a function of the inking rollers


04


, which, for example, lies between 0.35 and 0.5 m.




For pre-inking, the speed of the inking roller


04


lies, for example, between 1.9 to 4.0 m/s, and for washing the speed lies between 0.08 and 0.3 m/s. For continued running, the speed of the inking roller


04


lies, for example, between 0.95 and 1.95 m/s.




In case where the circumference of the screen roller


04


lies in the lower circumferential range or below, such as is advantageous, for example, in case of a double-sized forme cylinder


01


during direct printing operations, in an advantageous embodiment the above mentioned ranges of the rotational speeds for the screen roller


04


should be increased by the appropriate rotational speed, for example by 0 to 30%, and in particular by 10 to 20%, so that the range for the speed is approximately maintained.




Suitable, or desired rotational speeds for the rotating bodies


01


,


02


,


04


, which are embodied as cylinders


01


,


02


and rollers


04


, can be determined by the advantageous speeds, if the effective circumferences for various diameters are known.




In the drawing figures, the inking rollers


04


are generalized and are represented with a uniform diameter for the sake of simplicity. The operational states are described by rotational speeds in the preferred embodiments. However, the same embodiments can also be read from the speeds characterizing the operational speeds.




To limit the number of drawing figures, the arrangement of the cylinders


01


,


02


and rollers


04


in

FIGS. 1

to


4


is represented in which the rotatable bodies


01


,


02


and


04


are spaced apart from each other. The states of cylinders


01


,


02


, or rollers


04


, which are placed against or away from each other, ensue from the descriptions of the preferred embodiments and they can therefore not be taken from the mentioned drawing figures alone.

FIGS. 5 and 6

represent states described in the preferred embodiments for placing cylinders, or rollers, against or away from each other.




A first group of examples are shown with reference to FIG.


1


and form first to eighth preferred embodiments, and describe advantageous operational states for a first cylinder pair


07


consisting of the forme cylinder


01


and the cooperating transfer cylinder


02


.




In a first example, the forme cylinder


01


rotates at the set-up rotational speed RFZ for the purpose of pre-inking, in this case at the rotational speed VEFZ characteristic or required for pre-inking. The transfer cylinder


02


is in the stopped state NÜZ, for example in order not to further convey an already drawn-in web


06


, which results in a reduction of waste. The forme cylinder


01


can have a cooperating inking roller


04


, which is either coupled with it or, in an advantageous manner, also rotates independently of the forme cylinder


01


. In the present preferred embodiment, it rotates in the opposite direction of rotation at the set-up rotational speed RW corresponding to the circumferential speed of the forme cylinder and is placed against the latter. The set-up rotational speed RW, in this case the rotational speed VEW, for pre-inking the inking roller


04


need not be identical to that of the forme cylinder


01


. Instead it is a function of the circumferential ratio between the forme cylinder


01


and the inking roller


04


.




In a second example, the forme cylinder


01


continues to rotate at the rotational speed VEFZ for pre-inking, while the transfer cylinder


02


rotates at the rotational speed RÜZ corresponding to the rotational speed WÜZ for washing the transfer cylinder.




In a third example, the forme cylinder


01


rotates at the rotational speed VEFZ for pre-inking, while the transfer cylinder


02


rotates at the set-up rotational speed RÜZ corresponding to the rotational speed EÜZ for drawing in the web


06


.




In a fourth example, the forme cylinder


01


rotates at the rotational speed RFZ, in this case at the rotational speed DWFZ for changing the printing forme. At the same time, the transfer cylinder


02


rotates at the rotational speed EÜZ for drawing in the web


06


. In the case of a direct image transfer to forme cylinders


01


, the forme cylinder


01


rotates at the rotational speed BBFZ for transferring images to the forme cylinder


01


.




In the fifth example, the forme cylinder rotates at the rotational speed BBFZ for image transfer to the forme cylinder


01


, while the transfer cylinder


02


is in the stopped state NÜZ. The forme cylinder


01


and the transfer cylinder


02


are moved away from each other. The inking roller


04


is moved away and is, for example, in the stopped state NW.




In the sixth example, the forme cylinder


01


rotates at the rotational speed DWFZ for changing the printing forme, while the transfer cylinder


02


rotates at the rotational speed WÜZ for washing. Here it is also possible, in the case of a direct image transfer to forme cylinders


01


, that the latter alternatively rotates at the rotational speed BBFZ for transferring images. The forme cylinder


01


and the transfer cylinder


02


are moved away from each other. The inking roller


04


is moved away from the forme cylinder


01


and, for example, rotates also at the set-up speed rotational speed RW, the rotational speed VEW for pre-inking, the rotational speed WW for washing the inking roller


04


, or the rotational speed WLW for continued running of the inking roller


04


for preventing it from drying out.




In the seventh example, the forme cylinder


01


is in the stopped state NFZ while the transfer cylinder


02


rotates at the rotational speed EUZ for drawing in the web


06


. The inking roller


04


can be in or out of contact.




In the eighth example also, the forme cylinder


01


is in the stopped state NFZ, while the transfer cylinder


02


, however, rotates at the rotational speed WUZ for washing the transfer cylinder


02


. Here too, the inking roller can be in or out of contact.




In a group of examples shown in

FIG. 2

, specifically ninth to fourteenth examples, the first pair


07


cooperates in a print-on position via the web


06


with a second pair


08


of cylinders


09


,


11


consisting of, for example, a second forme cylinder


09


and a second transfer cylinder


11


. In principle, all of the operational states in the first to eighth examples of the first pair


07


are possible for the second pair


08


, parallel and independently of the operational state of the first pair


07


. However, the second pair


08


could be mechanically coupled. In what follows, some advantageous operational modes are described for a four-cylinder printing unit


12


, for example a bridge printing unit


12


.




In a ninth example, the two transfer cylinders


02


,


11


are placed against each other and each rotate, together with one of the forme cylinder


09


,


01


, at the production rotational speed PFZ, PÜZ, while the other one of the two forme cylinder


01


,


09


rotates at one of the set-up rotational speeds RFZ. In this case, the set-up rotational speed RFZ represents, for example, the rotational speed BBFZ for image transfer. The forme cylinder


09


,


01


rotating at the production rotational speed PFZ is preferably placed against the associated transfer cylinder


11


,


02


and rotates in the opposite direction of rotation to the cooperating transfer cylinder


11


,


02


which, in turn, rotates in the opposite direction to the other transfer cylinder


02


,


11


.




In a variation of the ninth example, the forme cylinder


01


,


09


, which is not rotating at the production rotational speed PFZ can also be rotating at the rotational speed VEFZ for pre-inking the forme cylinder


01


,


09


.




In a tenth example, the two transfer cylinders


02


,


11


rotate at the production rotational speed PÜZ, the same as in the ninth example, while the two forme cylinders


01


,


09


rotate at the production rotational speed RFZ, in particular at the rotational speed BBFZ for image transfer, and are moved away from the transfer cylinder


02


,


11


.




In an also advantageous variation of the tenth example, the forme cylinders


01


,


09


are at the rotational speed VEFZ for pre-inking.




In an eleventh example depicted in

FIG. 6

, the two transfer cylinders


02


and


11


rotate at one of their set-up rotational speeds RÜZ, for example at a rotational speed EÜZ for drawing in the web


06


, while both forme cylinders


01


,


09


are moved away from each associated transfer cylinder and rotate also at one of their set-up rotational speeds RFZ, for example at the rotational speed PWFZ for changing the printing forme, or alternatively at the rotational speed BBFZ for image transfer. The forme cylinders


01


,


09


and the associated transfer cylinders


02


,


11


are not placed against each other. The inking roller


04


is also moved away from the forme cylinder


01


.




In the same way, and as mentioned in connection with the first eight examples, only one of the forme cylinders


01


,


09


can rotate at one of its set-up rotational speed RFZ, while the assocaited transfer cylinder


02


,


11


has one of its set-up numbers RÜZ.




In a twelfth example, one of the two forme cylinders


01


,


02


from the eleventh example is in the stopped state NFZ.




In the thirteenth example depicted in

FIG. 6

, the two transfer cylinders


02


,


11


are in the stopped state NÜZ, while at least one of the two forme cylinders


01


,


09


rotates at the rotational speed VEFZ for pre-inking. In an advantageous embodiment, the inking cylinder


04


shown, in dashed lines in

FIG. 6

, which also rotates at its rotational speed VEW for inking, is placed against this forme cylinder


01


,


09


.




In the fourteenth example, also depicted by referring to

FIG. 6

, both transfer cylinders


02


and


11


rotate at the rotational speed EÜZ for drawing in the web


06


, while at least one of the two forme cylinders


01


,


09


, and preferably both of the forme cylinders


01


,


09


, are in the stopped state NFZ.




In a third group of examples, specifically examples fifteen to twenty as shown in

FIG. 3

, a third pair


13


of cylinders


14


,


16


, consisting, for example, of a third forme cylinder


14


and a third transfer cylinder


16


, are or can be placed against either the transfer cylinder


02


, or


11


of one of the two pairs


07


,


08


. In principle, all of the operational states of the first to eight examples are possible for this third pair


13


, parallel and independently of the operational state of the first pair


07


or the second pair


08


, as well as parallel and independently of the operational states of the four-cylinder printing unit


12


. The cylinders


14


,


16


of the third pair


13


could also be mechanically coupled with each other, or could be operated in any other way in accordance with the conventional prior art. In what follows, some advantageous modes of operation for a six-cylinder printing unit


17


, for example a Y-printing unit


17


, or lambda-printing unit


17


, will be described.




In a fifteenth example, two of the forme cylinders


01


,


09


,


14


, for example the forme cylinders


01


and


09


, as well as the two associated transfer cylinders


02


,


11


, rotate at the production rotational speed PFZ, PÜZ, while the third forme cylinder


14


rotates at the set-up rotational speed RFZ. In the present example, the associated transfer cylinder


16


is placed against the first transfer cylinder


02


of the first pair


07


and also rotates at the production rotational speed PÜZ.




In the sixteenth example, the third transfer cylinder


16


from the fifteenth example is moved away from the first transfer cylinder


02


, as well as from the third forme cylinder


14


, and is in the stopped state NÜZ.




In the seventeenth example, the third transfer cylinder


16


from the fifteenth example is moved away from the first transfer cylinder


02


, as well as from the third forme cylinder


14


as in the sixteenth example, but rotates at the setup rotational speed RÜZ, and in particular the rotational speed WÜZ for washing the transfer cylinder


02


,


11


,


16


.




In the eighteenth example, the three transfer cylinders


02


,


11


,


16


rotate at the rotational speed EÜZ for drawing in the web


06


, while the forme cylinders


01


,


09


,


14


are in the stopped state NFZ.




In the nineteenth example, the three transfer cylinders


02


,


11


,


16


rotate at the rotational speed EÜZ for drawing in the web


06


, while at least two of the forme cylinders


01


,


09


,


14


rotate at the set-up rotational speed RFZ, in particular the rotational speed DWFZ for changing the dressing, or alternatively at the rotational speed BBFZ for image transfer to the forme cylinders


01


,


09


,


14


.




In the twentieth example, the three transfer cylinders


02


,


11


,


16


are in the stopped state NÜZ, while at least two of the forme cylinders


01


,


09


,


14


rotate at the set-up rotational speed RFZ, and in particular at the rotational speed BBFZ for image transfer to the forme cylinders


01


,


09


,


14


.




In a fourth group of examples, as shown in FIG.


4


and specifically examples twenty one and twenty eight, the third cylinder pair


13


is not placed against the first or second cylinder pair


07


,


08


, but instead constitutes a second four-cylinder printing unit


22


together with a fourth pair


18


of cylinders


19


,


21


, for example a fourth forme cylinder


19


and a fourth transfer cylinder


21


. This second four-cylinder printing unit


22


, configured, for example as a second bridge printing unit


22


, forms an eight-cylinder printing unit


23


together with the first four-cylinder printing unit


12


. In principle, all of the operational states in the first to eighth examples, as well as the ninth to fourteenth examples, are possible for the cylinder pairs


13


,


18


, or for the second four-cylinder printing unit


22


, which may be operating parallel and independently of the operational state of the first cylinder pairs


07


,


08


or the first four-cylinder printing unit


12


.




The cylinders


19


,


21


of the fourth cylinder pair


18


can also be operated in any other way in accordance with the conventional prior art, for example they can be mechanically coupled with each other. The two bridge units


12


,


22


can be arranged, respectively vertically oriented next to each other, or respectively horizontally oriented on top of each other, or can be mirrored along an imagined horizontal line, forming a so-called H-unit. In what follows, some advantageous modes of operation for the eight-cylinder printing unit


23


are described.




In the twenty-first example, all cylinders


01


,


02


,


09


,


11


of the first lower four-cylinder printing unit


12


which, for example, is vertically oriented, rotate at the production rotational speed PFZ, PÜZ. Also, one of the two pairs


13


,


22


arranged at the top, the pair


13


in this example, as well as the transfer cylinder


21


of the fourth pair


18


, rotate at the production rotational speed PFZ, PÜZ. The transfer cylinders


02


,


11


of the lower four-cylinder printing unit


12


, as well as the transfer cylinders


16


,


21


have been placed against each other. The forme cylinder


19


of the fourth pair


18


rotates at one of its set-up rotational speeds RFZ, for example at the rotational speed BBFZ for image transfer to the forme cylinders


01


,


09


,


14


,


19


. The two transfer cylinders


02


,


16


arranged at the left on top of each other, rotate in the same direction of rotation, for example left-rotating, while the two associated transfer cylinders


11


,


21


rotate in the opposite direction, for example right-rotating. The respectively associated forme cylinders


01


,


09


,


14


, which rotate at the production rotational speed PFZ, rotate opposite the respective cooperating transfer cylinder


02


,


11


,


16


. Upper and lower four-cylinder printing units


12


,


22


can also be interchanged.




In the twenty-second example, all cylinders


14


,


16


,


19


,


21


of the second, for example horizontally oriented upper four-cylinder printing unit


22


rotate at the production rotational speed PFZ, PÜZ. Also, the two transfer cylinders


02


,


11


, which are arranged at the bottom, of the first or second cylinder pair


07


or


08


rotate at the production rotational speed PÜZ. The transfer cylinders of the lower four-cylinder printing unit


12


, as well as the transfer cylinders


16


,


21


, are each placed against each other. The forme cylinders


01


,


09


of the first and second cylinder pair


07


,


08


are moved away from the transfer cylinders


02


,


11


, wherein at least one of the two forme cylinders


01


,


09


rotates at one of its set-up rotational speeds RFZ, for example at the rotational speed BBFZ for image transfer to the forme cylinders


01


,


09


,


14


,


19


. The upper and lower four-cylinder printing units


12


,


22


, or the pairs cylinder


07


,


08


,


13


,


18


arranged at the left and right in the examples, can be interchanged.




In a twenty-third example, the cylinders


14


,


16


,


19


,


21


of the upper four-cylinder printing unit


22


, as well as the unit


12


, rotate at the production rotational speed PFZ, PÜZ. The transfer cylinders


02


,


11


,


16


,


21


are placed in pairs against each other, while the two forme cylinders


01


,


09


of the lower four-cylinder printing unit


12


are moved away and rotate at a set-up rotational speed RFZ, in particular the rotational speed BBFZ for image transfer. In an advantageous variation of the twenty-third example, the forme cylinders


01


,


09


are in the stopped state NFZ.




In a twenty-fourth example, all four transfer cylinders


02


,


11


,


16


,


21


rotate at one of their set-up rotational speeds RÜZ, for example at the rotational speed EÜZ for drawing in the web


06


, which is not specifically represented in

FIG. 4

, while at least one of the forme cylinders


01


,


09


,


14


,


19


, and in an advantageous embodiment at least the two forme cylinders


01


,


09


,


14


,


19


of at least one of the two four-cylinder printing units


12


,


22


rotates at one of its set-up rotational speeds RFZ, for example at the rotational speed DWFZ for changing the printing forme, or alternatively at the rotational speed BBFZ for image transfer to the forme cylinders


01


,


09


,


14


,


19


. The remaining forme cylinders


19


,


14


,


09


,


01


are, for example, in the stopped state NFZ.




In the twenty-fifth example, all but two cylinders


01


,


02


,


09


,


11


,


14


,


16


,


19


,


21


rotate as in the twenty-fourth example, but two forme cylinders


01


,


09


,


14


,


19


of at least one four-cylinder printing unit


12


,


22


rotate at the rotational speed VEFZ for pre-inking.




In a twenty-sixth example, each of the cylinders


01


,


02


,


14


,


16


,


19


,


21


of the three cylinder pairs


07


,


13


,


18


rotates at the production rotational speed PFZ, PÜZ, while the forme cylinder


09


of the second cylinder pair


08


rotates at one of its set-up rotational speeds RFZ, for example at the rotational speed VEFZ for pre-inking, and the associated transfer cylinder


11


rotates at one of its set-up rotational speeds RÜZ, for example the rotational speed WÜZ for washing of the transfer cylinder


11


. However, in this case, the transfer cylinder


11


can also be in the stopped state NÜZ, or can rotate at the rotational speed AWÜZ for the change of the dressing.




In another advantageous alternative of the twenty-sixth example, the forme cylinder


09


, which is not at the production rotational speed PFZ, rotates at the rotational speed DWFZ for changing the printing forme or, in the case of a forme cylinder


09


for direct image transfer, at the rotational speed BBFZ for image transfer.




In a twenty-seventh example, all four transfer cylinders


02


,


11


,


16


,


21


are in the stopped state NÜZ, while the two forme cylinders


01


,


09


,


14


,


19


of at least one of the two four-cylinder printing units


12


,


22


rotate at the set-up rotational speed RFZ, and in particular at the rotational speed VEFZ for pre-inking the printing form. In an advantageous embodiment, all of the forme cylinders


01


,


09


,


14


,


19


rotate at the rotational speed VEFZ for pre-inking the printing forme.




In a twenty-eighth example, one transfer cylinder


02


,


11


,


16


,


21


, for example the transfer cylinder


02


, rotates at the set-up rotational speed RÜZ, in particular at the rotational speed WÜZ for washing the transfer cylinder


02


, while the associated forme cylinder


01


,


09


,


14


,


19


, for example the forme cylinder


01


, rotates at one of its set-up rotational speeds RFZ, for example at the rotational speed VEFZ for pre-inking. However, corresponding to the cylinder pair


12


from the first to eighth examples, two transfer cylinders or, corresponding to the ninth to fourteenth examples for the four-cylinder printing unit


12


,


22


, all four transfer cylinders


02


,


11


,


16


,


21


can be operated at one of their set-up rotational speeds RÜZ, for example WÜZ for washing, and the associated forme cylinders


01


,


09


,


14


,


19


at one of their set-up rotational speeds RFZ, for example the rotational speed VEFZ for pre-inking.




In the described examples, at least the cylinders


01


,


02


,


09


,


11


,


14


,


16


,


19


,


21


,


24


,


32


are driven by their own drive motor. In a preferred embodiment, however, all cylinders


01


,


02


,


09


,


11


,


14


,


16


,


19


,


21


,


24


,


32


of the described printing units can be individually driven by their own drive motors without a driven coupling to another cylinder


01


,


09


,


11


,


14


,


16


,


19


,


21


,


24


,


32


, or inking system. In that case, the drive motors then drive the respective cylinder


01


,


02


,


09


,


11


,


14


,


16


,


19


,


21


,


24


,


32


, or the inking system, during set-up operations, as well as during production.




The employment of position-regulated and/or rpm-regulated electric motors is of particular advantage. This also applies to the drives of the rollers


04


, which can either have their own drive motor, or the inking system containing the roller


04


has a drive motor, which is independent of the cylinders


01


,


02


,


09


,


11


,


14


,


16


,


19


,


21


,


24


,


32


.




While preferred embodiments of a printing unit in accordance with the present invention have been set forth fully and completely hereinabove, it will be apparent to one of skill in the art that changes in, for example, the specific type of web being printed, the overall size of the printing unit, and the like could be made without departing from the true spirit and scope of the present invention which is accordingly to be limited only by the following claims.



Claims
  • 1. A printing unit with at least four cylinders comprising:a first cylinder pair including a first forme cylinder and a first transfer cylinder; a second cylinder pair including a second forme cylinder and a second transfer cylinder, at least said first and second transfer cylinders cooperating in a print-on position of the printing unit; and a separate drive motor for each cylinder in each said cylinder pair, said forme cylinder and said transfer cylinder in each said first and second cylinder pair being driven by their own drive motor and not being in connection with other ones of the cylinders during set-up and production operations of the printing unit, each said individually drive transfer cylinder being operable selectively at one of a plurality of transfer cylinder speeds, including a set-up rotation speed for washing said transfer cylinder or for drawing in a web, a production rotational speed, and a zero rotational speed, said transfer cylinder set-up rotational speed, production rotational speed and zero rotational speed each being different from the others, said forme cylinder in each said cylinder pair being operable selectively at one of a plurality of forme cylinder speeds including a set-up rotational speed, a production rotational speed and a zero rotational speed each being different from the others, said forme cylinder and said transfer cylinder in each said cylinder pair each being simultaneously operable at a selected one of said transfer cylinder speeds and said forme cylinder speeds independently.
  • 2. The printing unit of claim 1 wherein said first and second cylinder pairs form a first four-cylinder printing unit.
  • 3. The printing unit of claim 1 further including a third cylinder pair including a third forme cylinder and a third transfer cylinder, said first, second and third cylinder pairs forming a six-cylinder printing unit.
  • 4. The printing unit of claim 2 further including a second four-cylinder printing unit, said first and second four-cylinder printing units being arranged adjacent each other and forming an eight-cylinder unit.
  • 5. The printing unit of claim 1 wherein said forme cylinder set-up rotational speed is equal to a rotational speed for a change of a printing forme on said forme cylinder.
  • 6. The printing unit of claim 1 wherein said forme cylinder set-up rotational speed is equal to a rotational speed for an image transfer to said forme cylinder.
  • 7. The printing unit of claim 1 wherein said forme cylinder set-up rotational speed is equal to a rotational speed for pre-inking said forme cylinder.
  • 8. The printing unit of claim 1 wherein said forme cylinder set-up rotational speed is equal to a rotational speed for a dry running of said forme cylinder.
  • 9. The printing unit of claim 1 further including a separate one of said drive motors for all cylinders in the printing unit.
  • 10. The printing unit of claim 1 wherein each said separate drive motor is a position-regulated electric motor.
  • 11. The printing unit of claim 1 wherein each said separate drive motor is an rpm-regulated electric motor.
  • 12. The printing unit of claim 1 wherein said production rotational speed is determined by a desired circumferential speed.
  • 13. The printing unit of claim 1 wherein said set-up rotational speed is determined by a desired circumferential speed.
  • 14. A printing unit with at least four cylinders comprising:a first cylinder pair including a first forme cylinder and a first transfer cylinder; a second cylinder pair including a second forme cylinder and a second transfer cylinder, at least said first and second transfer cylinders cooperating in a print-on position of the printing unit; and a drive motor for at least each of said transfer cylinder and said forme cylinder in each said at least first and second cylinder pairs, each said drive motor driving its associated cylinder and not being coupled to any one of the cylinders remaining in each said cylinder pair during set-up operation and production of the printing unit, at least each individually driven forme cylinder being operable selectively at one of a plurality of forme cylinder speeds including a set-up rotational speed for pre-inking or image transfer to said forme cylinder, a production rotational speed, and a zero rotational speed, said plurality of forme cylinder speeds all being different from each other, said transfer cylinder in each said cylinder pair being operable selectively at one of a plurality of transfer cylinder speeds including a zero rotational speed and a production rotational speed not equal to said zero rotational speed, said forme cylinder and said transfer cylinder being simultaneously operable at selected ones of said forme cylinder speeds and said transfer cylinder speeds independently.
  • 15. The printing unit of claim 14 wherein said first and second cylinder pairs form a first four-cylinder printing unit.
  • 16. The printing unit of claim 14 further including a third cylinder pair including a third forme cylinder and a third transfer cylinder, said first, second and third cylinder pairs forming a six-cylinder printing unit.
  • 17. The printing unit of claim 15 further including a second four-cylinder printing unit, said first and second four-cylinder printing units being arranged adjacent each other and forming an eight-cylinder unit.
  • 18. The printing unit of claim 14 further including a separate one of said drive motors for all cylinders in the printing unit.
  • 19. The printing unit of claim 14 wherein each said separate drive motor is a position-regulated electric motor.
  • 20. The printing unit of claim 14 wherein each said separate drive motor is an rpm-regulated electric motor.
  • 21. The printing unit of claim 14 wherein said production rotational speed is determined by a desired circumferential speed.
  • 22. A printing unit with at least four cylinders comprising:a first cylinder pair including a first forme cylinder and a first transfer cylinder; a second cylinder pair including a second forme cylinder and a second transfer cylinder, said first and second transfer cylinders cooperating in a print-on position of the printing unit; and a drive motor for each of said forme cylinder and said transfer cylinder in each of said at least first and second cylinder pairs, each said drive motor driving its associated cylinder with not driving coupling to another one of said cylinders during set-up and production of the printing unit, at least one of said first and second transfer cylinders having a rotational speed for washing said transfer cylinders or for drawing in a web which differs from a production rotational speed and a zero rotational speed of said transfer cylinder, said associated forme cylinder of said one of said first and second cylinder pairs having a zero rotational speed while said transfer cylinder is in said rotational speed for washing said transfer cylinder or for drawing in a web.
  • 23. The printing unit of claim 22 wherein said first and second cylinder pairs form a first four-cylinder printing unit.
  • 24. The printing unit of claim 22 further including a third cylinder pair including a third forme cylinder and a third transfer cylinder, said first, second and third cylinder pairs forming a six-cylinder printing unit.
  • 25. The printing unit of claim 23 further including a second four-cylinder printing unit, said first and second four-cylinder printing units being arranged adjacent each other and forming an eight-cylinder unit.
  • 26. The printing unit of claim 22 further including a separate one of said drive motors for all cylinders in the printing unit.
  • 27. The printing unit of claim 22 wherein each said separate drive motor is a position-regulated electric motor.
  • 28. The printing unit of claim 22 wherein each said separate drive motor is an rpm-regulated electric motor.
  • 29. The printing unit of claim 22 wherein said production rotational speed is determined by a desired circumferential speed.
Priority Claims (2)
Number Date Country Kind
100 46 374 Sep 2000 DE
100 46 370 Sep 2000 DE
PCT Information
Filing Document Filing Date Country Kind
PCT/DE01/03561 WO 00
Publishing Document Publishing Date Country Kind
WO02/24455 3/28/2002 WO A
US Referenced Citations (17)
Number Name Date Kind
4960048 Sarda Oct 1990 A
5103730 Sarda Apr 1992 A
5447102 Pfeiffer et al. Sep 1995 A
5617788 Horiguchi et al. Apr 1997 A
5660108 Pensavecchia Aug 1997 A
5787806 Seyfried et al. Aug 1998 A
5983793 Volz et al. Nov 1999 A
5983794 Emery Nov 1999 A
6032579 Richards Mar 2000 A
6032582 Franz et al. Mar 2000 A
6055907 Endisch et al. May 2000 A
6332397 Bolza-Schünemann et al. Dec 2001 B1
6408748 Hajek et al. Jun 2002 B1
6446553 Costin et al. Sep 2002 B1
6499402 Sikes et al. Dec 2002 B1
6543354 Straube et al. Apr 2003 B1
6578481 Beisel Jun 2003 B1
Foreign Referenced Citations (10)
Number Date Country
44 30 693 Mar 1996 DE
197 32 330 Feb 1997 DE
196 03 663 Aug 1997 DE
196 40 649 Apr 1998 DE
197 23 043 Dec 1998 DE
197 33 644 Feb 1999 DE
198 22 893 Nov 1999 DE
0 621 133 Oct 1994 EP
0 997 273 May 2000 EP
63125336 May 1988 JP
Non-Patent Literature Citations (1)
Entry
“Digitaler Direktantrieb an Druckmaschinen,” Druckspiegel, Sep. 1999, pp. 53-56.