CN1116986A

CN1116986A - Printing unit for a WEB-FED printing machine

Info

Publication number: CN1116986A
Application number: CN94116304A
Authority: CN
Inventors: 拉普·约阿希姆; 阿尔弗雷德·海因茨
Original assignee: De la Rue Giori SA
Current assignee: KBA Notasys SA
Priority date: 1993-09-17
Filing date: 1994-09-15
Publication date: 1996-02-21
Anticipated expiration: 2014-09-15
Also published as: AU7290994A; EP0649740B1; ATE168071T1; RU94033483A; EP0649740A1; RU2114741C1; KR950008126A; CA2117665A1; DE59406405D1; CN1051281C; JPH07148913A; CA2117665C; JP3464536B2; KR100336921B1

Abstract

The printing unit has two cylinders (1, 4) which exhibit printing saddles separated by cylinder grooves (3, 6). The paper web (7) passing the printing nip is transported in pilgrim-step operation in order to print adjoining formats. The two cylinders (1, 4) can be adjusted at an angle, with respect to the position of their printing saddles (2, 5) interacting in the nip, offset with respect to one another by a circumferential distance which is approximately equal to the difference between the circumferential length (S) of a printing saddle and the circumferential length (B) of a printed image. Consequently, the printed zone is only approximately as large as the printed image, and the printing-free zone available for drawing back the paper web is correspondingly enlarged.

Description

The printing unit that is used for web press

The present invention relates to a kind of printing unit that is used for web press, it has the cylinder of two crew-served formation printing roll gaps, as at the sheet-fed printing unit, cylinder has many printing saddles that separated by cylinder gap, so that adopt the different space of a whole page adjacent to each other on roll web, to print by the printing roll gap, this roll web paper web is transferred with a variable velocity in so-called Pilger mode (periodic) lining, and after each printing operation finishes, when paper web during through a cylinder gap periphery with respect to two cylinders be pulled and be accelerated again, like this, continuous printed image will enrank and is not stayed the gap.

Such printing unit has been done introduction for 360 li at United States Patent (USP) 5,062.The printing unit that these are known or have the hectographic printing parts of two crew-served blanket cylinders, on these two blanket cylinders all at the printed image of last printing ink, so that the paper positive and negative is printed, or have intaglio printing parts with the crew-served plate cylinder of an impression cylinder.The advantage of using the sheet-fed printing unit to print on continuous roll web paper web is and time-consumingly to make plate cylinder and impression cylinder or the blanket cylinder with continuous seamless circumferential surface with no longer needing difficulty; And can use the cylinder made from comparatively simpler method, they have spaced-apart printing saddle, and can install not really difficultly, adjust and change indivedual formes or printing blanket individually on each printing saddle.In addition, provide a kind of like this possibility with so-called Pilger mode (periodic) delivery roller paper, promptly can be owing to existing the gap of not printing to waste paper between the image, also can produce image adjacent to each other, therefore, cylinder gap can make and can not produce the not blank tape of printing between the continuous printed image.For this reason, as United States Patent (USP) 5,062,360 are introduced, the conveying of roll web is controlled by a control system, like this, and behind the one-step print EO, when cylinder gap that no longer nipped paper web aligns mutually through two cylinders, roll web at first is braked, and motion backward is last then, between the printing saddle of two cylinder pairings subsequently, clamped again, so that before then carrying out printing operation, accelerate to running speed again.Roll web is selectable with respect to the distance that the periphery of two cylinders is pulled, thereby realizes very close to each other, the continuous printed image of printing.Therefore, for this purpose, must control the Pilger motion mode, in this mode, after the Pilger step, roll web is positioned at same position at least approx with respect to the printing roll gap between two cylinders, that is to say as on the position identical in the machine before the Pilger step.

Because the result who adopts the Pilger step motion suitably to cooperate, just may utilize one one and same printing machine, even be under the various different space of a whole page situations at the image that will print, that is to say under short space of a whole page situation, also can make the printing image adjacent to each other and do not stay the gap.The forme that has the identical size of shorter printed image by installation can change printing surface, and the Printing Zone still remains unchanged, and does not shorten.

In known such web press, two cylinders are always installed relative to each other, in this mode, installation of its printing saddle need make it can be relatively strict mutually during co-operating in the printing roll gap, as illustrated in fig. 1 and 2, circumferential length is respectively arranged is three

printing saddles

2 and 5 of S to two cylinders 1 and 4.Therefore, simultaneously, the length D of Printing Zone (along it, roll web 7 is sandwiched between two cylinders) always strictly is equal to the circumferential length S that prints saddle, says with the circumferential length B of printed image (that is to say and the space of a whole page) irrelevant exactly.

The not Printing Zone that is present between two Printing Zones according to cylinder gap length G is always identical with the time interval that obtains by withdrawal roll web paper web.

Fig. 1 represents the beginning of printing operation, and Fig. 2 represents the end of printing operation, that is to say after cylinder rotates through an angle corresponding to Printing Zone length D along the direction shown in the arrow.If the maximum permission space of a whole page prints, that is to say if the circumferential length of the as many as printing saddle of the circumferential length of printed image, so, behind each printing operation, roll web paper web 7 is passing through cylinder gap 3 in free-moving mode and must be braked by this way in 6 o'clock, regain, and quicken again, promptly rely on print speed printing speed, can obtain to slow down and quicken, and the time by groove, when printing begins again, it seems still at same position, just as the position that was arrived before the Pilger step with respect to the printing roll gap.

Yet, if print the less space of a whole page, as illustrated in fig. 1 and 2, the circumferential length B of printed image is less than the circumferential length S of printing saddle, so, behind each printing operation, roll web paper web 7 must be retracted, and quickens through a bigger distance again, so that guarantee when printing begins again, the position of roll web is adjusted (opposite with the direction of motion) more backward with respect to the position of cylinder nip, its distance is the poor of Printing Zone length D and printed image length B, that is to say distance D-B.

In an example according to Fig. 1 and 2, printing starting point A overlaps with visual starting point, and the printing terminal point E of Printing Zone is positioned at the back of visual terminal point F, and their gap is D-B, represents their gap here with Z.Therefore, in this case, in case begin printing again, if on the roll web paper web, obtain continuous and very close to each other printed image mutually, roll web 7 must be with respect to nip between two cylinders along the direction opposite with the direction of motion distance of deflected length Z backward, as shown in Figure 1.

In fact, the length D of Printing Zone is always constant, even also is so when making the printed image that uses the less space of a whole page, therefore, exists following various shortcoming:

Behind each printing operation,, this means because the roll web paper web must be regained the length of a segment distance Z in addition, for the less space of a whole page, that is to say that for redundance Z compare with the mode of printing of the maximum print space of a whole page, roll web will produce a sizable deceleration and accelerated motion.Simultaneously, must consider following situation:

After the roll web paper web is through the Printing Zone d/d the time, it at first according to the size of the size of print speed printing speed and the obtainable deceleration segment distance that moves again, stops up to it.It is the most critical that this segment distance roll web has been passed by, because the accelerating period after roll web is static, it must be reconsidered into.Therefore, the roll web paper web must be regained 2 times of these distances, like this, after consequential acceleration, reaches print speed printing speed on the same point that it arrives again before the Pilger step.

If the length of printing saddle is slightly larger than the length of printed image, roll web can not be decelerated immediately after the printed image terminal point so, but further is transferred with print speed printing speed before the Pilger step can begin.As previously mentioned, this segment distance must be included in the Pilger step in addition.

Yet,, must reduce the speed of machine owing to be subjected to the restriction that roll web slows down and quickens.Like this, this loss of productivity ratio has double action, and promptly between each on-stream period, short printed image has produced, and in addition, its speed must reduce.

Also have, particularly in intaglio printing, roll web stands the high pressure compacting, this pressure can be up to 80 tons on every meter roll web web width, and are subjected to the compacting of the very smooth chrome-plated surface of forme, like this, after paper web is regained, and during the printing operation that then carries out, to being forced through on the paper web but the part Z that does not have an ink printing when printing, its quality will be poorer than the printing quality on the roll web paper web of not pressing.Fig. 1 and 2 has represented the roll web part Z of excessive pressurized and the part P of double pressurized.The compacting of part Z among Fig. 1 comes from printing operation formerly.

The objective of the invention is the shortcoming of avoiding above-mentioned, and a kind of printing unit is provided, it can not reduce productivity ratio during using a less space of a whole page instead, and can not carry out the secondary compacting to the roll web paper web.

According to the present invention, and utilize the described means of claim 1 characteristic can realize purpose of the present invention.

Introduce the present invention below by the detailed description to the embodiment of a demonstration in conjunction with the accompanying drawings.

Fig. 1 and 2 represents the known printing operation situation of sheet-fed press when in the Pilger mode roll web paper web of sending into being printed;

Fig. 3 and 4 expressions one are according to printing unit of the present invention and operational circumstances thereof.

Fig. 3 represents the beginning of one-step print operation, and Fig. 4 represents the end of this printing operation, even also say after two cylinders have rotated through an angle corresponding to printing length D.

Two cylinders 1 that draw among Fig. 3 and 4 and 4 (for example) are plate cylinder 4 and the impression cylinders 1 in the intaglio printing parts.The rotation direction of cylinder is represented by curved arrow.Two cylinders respectively have the

printing saddle

2 and 5 of three same sizes, and their circumferential length is S, and they are equally arranged at interval along their periphery, and are that the

cylinder gap

3 and 6 of G is spaced-apart by circumferential length.Printing blanket is installed on the printing saddle 2 of impression cylinder 1, and intaglio plate is installed on the printing saddle 5 of plate cylinder 4.Printed image on forme has a circumferential length B, and it is less than the length S of each printing saddle 5.

In the example of discussing, forme is to install like this, and the terminal point E of printed image overlaps with the terminal point of printing saddle 5 in the rotation direction back, and the starting point A of printed image B is with respect to the slightly skew of starting point of printing saddle 5.As shown in the figure, impression cylinder 1 is installed with respect to plate cylinder 4 angledly, like this,

printing saddle

2 and 5 crew-served and that belong to two cylinders is offset mutually on nip between the cylinder, in this case, the circumferential length D of Printing Zone (wherein crew-served galley saddle clip is lived roll web paper web 7) says the space of a whole page that includes only printing exactly, that is to say the circumferential length B that includes only printed image.Certainly, in fact printed image must slightly be longer than in the Printing Zone, thereby can be for the usefulness of the free edge that is imprinted on the printed image on the roll web paper web.

According to Fig. 3 and 4, the end points in the rotation direction front of the printing saddle 2 of impression cylinder 1 is offset a gap that equals S-B with respect to the end points that prints saddle 5 fronts.As mentioned above, this side-play amount is actually very little.

During printing operation, because these two cylinders 1 and 4 results that arrange like this, the nipped zone of roll web paper web dwindles, the circumferential length B of the space of a whole page that is substantially equal to print, the zone that its result does not print is added to length G+ (S-B), there is the more time to be used to regain the roll web paper web, that is to say to can be used to slow down and quicken.In addition, because the roll web paper web gains freedom at once after the terminal of printed image, so it does not need to regain extraly, and can be decelerated.So the roll web paper web must directly be clamped in the front of the starting point A of printed image, and gains freedom again immediately after the terminal point E of printed image.Its advantage is, stable deceleration with quicken momentum (they with drive relevant) situation under, the not Printing Zone by prolongation can increase machine speed.The length B of printed image is more little, and the Printing Zone is just not big more, and this is useful for the roll web paper web that is used for regaining relatively large part.

The another one advantage is that during printing operation, the roll web paper web does not have other part to be pushed down outside printed image, does not therefore just have the secondary that acts on the roll web secondary pressures partially P as shown in Figure 2 to suppress.

In the embodiment shown in Fig. 3 and 4, cylinder 1 can be a plate cylinder also, and cylinder 4 can be an impression cylinder.In this case, in the front of rotation direction, the starting point A of printed image overlaps with the terminal point of the printing saddle of plate cylinder, and like this, this plate cylinder is offset with respect to impression cylinder along the direction with direction of rotation.

The beneficial effect of the skew between, two crew-served cylinders above-mentioned in order to make full use of, the printed image on forme must or its starting point A overlaps with the starting point of corresponding printing saddle, or its terminal point E overlaps with the terminal point that prints saddle accordingly.

Embodiment shown in Fig. 3 and 4 also can be the hectographic printing parts that have two crew-served blanket cylinders, or only utilize the blanket cylinder of an inking to carry out the single face hectographic printing, or utilize the blanket cylinder of two inkings to carry out the positive and negative hectographic printing.Above-mentioned all advantages also are applicable to such hectographic printing parts.

The length D of Printing Zone and angle can be determined automatically.For this reason, in the embodiment shown in Fig. 3 and 4, one release member K is fixed on the circumference of impression cylinder, when requiring starting point (that is to say the starting point A of printed image) when the Printing Zone exactly through the line between the axle of two cylinders 1 and 4, release member K will move and pass through and excitation device its response, hard-wired or sensor I; Its position as shown in Figure 3.The response of sensor I produces a signal, and this signal enters by in the counter that is fixed on the rotary transmitter control on the plate cylinder 4, and this counter is a kind of impulse generator, and it is read a number and stores this reading.Similarly, have a release member L to be fixed on the plate cylinder 4, like this, the terminal point when the Printing Zone of plate cylinder that is to say that the terminal point E of printed image passes through the moment of described connecting shaft line exactly, and release member L is just through a fixing excitation device or sensor M; Its position as shown in Figure 4.The signal that sensor M produces causes the storage of second reading.Described two readings are as the reference value, so that be used for controlling carry-over pinch rolls, these carry-over pinch rolls are with Pilger step Move Volumes coil paper paper web 7.Difference between two readings can be used for measuring Printing Zone and Printing Zone not effectively, and the roll web paper web is freely in Printing Zone not.This mensuration is used to calculate the most appropriate deceleration and the accelerated motion during the Pilger step, thereby the roll web paper web is retracted and acceleration again, so that guarantee the no gap printing of roll web.Sensor I and M (for example) can be inductive pick-up or optical pickocff, if inductive pick-up, release member K or L can be iron blocks so.

Usually, the time interval between these two signals and two signals is represented measured value, and this measured value determines the angle position and the length of Printing Zone respectively under cylinder 1 and 4 given velocities of rotation.

Claims

1. printing unit that is used for web press, it have two crew-served, form the cylinder (1 of printing roll gap, 4), as in a sheet-fed printing unit, they have many by cylinder gap (3,6) the printing saddle (2 that separates, 5), so that on reel paper web (7), stamp the different space of a whole page adjacent to each other by the printing roll gap, this reel paper web is transferred with a variable velocity in so-called Pilger mode (periodic) lining, after each printing operation finishes, when it during through a cylinder gap with respect to two cylinders (1,4) periphery is pulled, and be accelerated again, like this, continuous printed image is just formed a line and is not stayed the gap, wherein, two cylinders (1,4) install mutually angledly, on them, crew-served in the printing roll gap, printing saddle (2,5) space of a whole page size is depended in position) circumferential distance of skew, this circumferential distance equals to print saddle (2 at least, the circumferential length (B) of circumferential length 5) (S) and printed image poor, like this, the length (D) of utilizing two galley saddle clips through the nip between the printing roll gap to stay in the Printing Zone of its reel paper web between two equals the circumferential length (B) of printed image.

2. printing unit as claimed in claim 1, it is characterized in that, first release member (K) is fixed on the periphery of cylinder (1), the starting point that goes up printing saddle (2) at cylinder (1) with respect to the rotation direction of cylinder corresponding to the starting point (A) of printed image, first sensor (I) to this release member response is fixed near this roll circumference face place, second release member (L) is fixed on the periphery of another cylinder (4), go up the terminal point (E) of the terminal point of printing saddle at this cylinder (4) corresponding to printed image, second sensor (M) to this release member (L) response is fixed near this roll circumference face place, described release member and sensor are to install like this and design, when the printing saddle (2) of first cylinder (1) through two cylinders (1,4) first sensor (I) produces one first signal during the line of axis, when crew-served with described printing saddle, the terminal of printing saddle (5) that belongs to second tin roller (4) is during through described line, second sensor (M) produces a secondary signal, the described signal and the time interval between two signals are represented the measured value of the circumferential length of angle position and Printing Zone, so that control its operation in the Pilger mode during by Printing Zone not at roll web paper web (7).