EP0005715A1 - Transfer cylinder with two sheet-supporting surfaces for convertible perfecting printing machines - Google Patents

Abstract

A transfer drum for face and reverse printing presses has two opposing sheet support surfaces (15) which are each formed by two comb-like groups of sheet supports (8, 11). A device (9) for detecting the leading edge of the sheet is provided on one of the two sheet carrier groups (8, 11) of each sheet supporting surface (15). The two arch support groups forming an arch support surface (8, 11) can be adjusted relative to one another about the rotational axis of the transfer drum. Furthermore, each arch support (8, 11) is firmly connected to a diametrically opposed arch support of the other arch support surface to form a unit and is arranged on the axis (3) of the transfer drum. At least one of the two sheet support units is radially adjustable on the axis of the transfer drum. This adjustability enables the concentricity and shape errors of the transfer drum to be corrected.

Description

The invention relates to a transfer drum for perfecting machines with two sheet support surfaces, each of which is formed by two interlocking sheet carrier combs, one sheet carrier comb having a device for detecting the leading edge of the sheet and at least one of the two interlocking sheet carrier combs being adjustable relative to the other about the axis of rotation of the transfer drum .

The manufacture of the transfer drums of the type mentioned at the outset requires a very high level of accuracy because the sheets transported by the two sheet support surfaces must be transferred in exactly the same way, otherwise duplication occurs.

• In der Regel bestehen solche Umführtrommeln aus einem feststehenden Trommelteil mit zwei sich diametral gegenüberliegenden Einrichtungen zum Erfassen der Bogenvorderkante und einem um die Rotationsachse verstellbaren Trommelteil mit zwei sich ebenfalls diametral gegenüberliegenden Einrichtungen zum Erfassen der Bogenhinterkante. Der jeweilig transportierte Bogen liegt auf der Bogentragfläche glatt auf. Unter Umständen sind z. B. Saugvorrichtungen vorhanden, um diese Auflage sicherzustellen. Wenn nun eine der Bogentragflächen zufolge eines Rundlauf- oder Formfehlers höher liegt als die andere, fällt die Lage des Druckendes zweier aufeinanderfolgender Bogen unterschiedlich aus. Die Folge davon ist ein rhytmisches Dublieren bei dem Druck nach der Bogenwendung. Ein Rundlauffehler von beispielsweise 0,02 mm kann, je nach Bogenlänge, bereits ein Dublieren von ca. 0,05mm zur Folge haben.

The cause is the following:

• As a rule, such transfer drums consist of a stationary drum part with two diametrically opposed devices for gripping the leading edge of the sheet and an adjustable drum part with two diametrically opposite devices for grasping the trailing edge of the sheet. The respectively transported sheet lies flat on the sheet supporting surface. Under certain circumstances. B. suction devices available to ensure this support. If one of the sheet wings is higher than the other due to a runout or shape error, the position of the print end of two consecutive sheets is different. The consequence of this is a rhythmic duplication when printing after the sheet is turned. A concentricity error of 0.02 mm, for example, can already result in a duplication of approx. 0.05 mm, depending on the length of the sheet.

In the case of perfecting presses known on the market, a height which may have been determined after the printing of the machine hen Difference of the sheet support surfaces of the transfer drum by sticking the lower lying sheet support surface with adhesive strips, for. B. aluminum foils, balanced. However, the adhesive strips can come off again by cleaning the surfaces. In addition, applying the various adhesive strips is cumbersome and time-consuming,

The invention provides a remedy here. According to the task, a device is to be provided on the transfer drum of a perfecting machine, by means of which, after the printing of the machine, duplication phenomena which can be attributed to concentricity or shape errors of the transfer drum can be eliminated.

According to the invention, this object is achieved in that parts of the arch wings or the arch wings as a whole are radially adjustable. This not only makes it possible to compensate for radial runout and form errors, but also for later changes to the adjustable parts of the transfer drum.

A particularly advantageous embodiment of the invention, consisting of a basic drum body with arch supports and the device for grasping the leading edge of the drum, and a hollow body with arch supports partially encompassing the basic drum body and a device for grasping the trailing edge of the bow, provides that the hollow body is provided on the basic drum body two cylinder journals are mounted on a slide ring, that play is provided between the cylinder journal and the slide ring and that adjusting screws are arranged in the hollow body, which act on the slide ring and locally eliminate the play between the inner surface of the slide ring and the cylinder journal running surface or adjust the arc carrier radially len.

This embodiment of the invention not only permits the radial adjustment of the entire arch support surfaces, but also enables the adjustable hollow body to be adjusted and aligned in a very simple manner during the initial assembly or during subsequent repair assemblies without play.

A further advantageous embodiment of the invention relates to a transfer drum with a sheet carrier comb composed of individual sheet support segments, at one end of which the device for detecting the leading edge of the sheet is provided, and with a further sheet carrier comb likewise formed from individual sheet support segments, at one end of which a device for detecting the The trailing edge of the arch is arranged, all of the arch support segments being mounted on a common axis.

In such a transfer drum, some or all of the arch support segments are mounted on the axle via a slide ring, play being provided between the inner surface of the slide ring and the axle and furthermore adjusting screws are arranged in the arc support segments provided with a slide ring, which act on and through the slide ring Deforming the slide ring Eliminate the clearance between the inner surface of the slide ring and the axle locally or adjust the arch support segments radially.

In addition to the advantage of compensating concentricity and shape errors, the inventive measures here also offer the possibility of adjusting the individual arch support segments to one another in a simple manner.

The two mentioned embodiments of the invention can also experience such a modification that, with the elimination of the slide rings, the set screws act directly on the cylinder running surface or on the axle. There is also the possibility, if one disregards the adjustment of the entire arch support surface, certain surface parts of the arch support surfaces, e.g. B. in the form of rails, adjusting bolts or blocks adjustable in height. You can also provide the arch support combs or the arch support segments with adjusting screws, by means of which the arch supports can be deformed, in such a way that the free ends of the arch support can be adjusted radially.

The invention is explained in more detail below with reference to some embodiments shown in the drawing.

• Fig. 1 eine Seitenansicht einer Umführtrommel mit zwei Bogentragflächen, bei der ein Teil der Bogentragflächen durch Stellschrauben radial verstellbar ist,
• Fig. 2 einen Längsschnitt durch die Umführtrommel nach Fig. 1, .
• Fig. 3-5 ein Lager des auf den Zylinderzapfen der Umführtrommel verstellbar angeordneten Hohlkörpers mit unterschiedlicher Einstellung der Stellschrauben,
• Fig. 6 eine Umführtrommel mit zwei Bogentragflächen, die aus zwei Gruppen von auf einer Achse aufgesteckten Bogentragsegmenten gebildet ist,
• Fig. 7 die Umführtrommel gemäß Fig. 6, wobei vier Bogentragsegmente an ihren Lagerungen mit Stellschrauben versehen sind,
• Fig. 8 eine Umführtrommel nach der Erfindung mit radial verstellbaren Klötzchen in den Bogentragflächen, und zwar unmittelbar vor der Einrichtung zum Erfassen der Bogenhinterkante und
• Fig. 9 eine Umführtrommel nach der Erfindung, bei der mittels Stellschrauben die hinteren Enden der Bogenträger in radialer Richtung nach außen gebogen werden können.

It shows:

• 1 is a side view of a transfer drum with two bow wings, in which a part of the bow wings is radially adjustable by adjusting screws,
• 2 shows a longitudinal section through the transfer drum according to FIG. 1.
• 3-5 a bearing of the hollow body which is adjustably arranged on the cylinder journal of the transfer drum with different adjustment of the adjusting screws,
• 6 shows a transfer drum with two arch support surfaces, which is formed from two groups of arch support segments plugged onto an axis,
• 7, the transfer drum according to FIG. 6, four arch support segments being provided with adjusting screws on their bearings,
• Fig. 8 is a transfer drum according to the invention with radially adjustable blocks in the sheet supporting surfaces, namely immediately before the device for detecting the sheet trailing edge and
• Fig. 9 is a transfer drum according to the invention, in which the rear ends of the sheet carrier can be bent in the radial direction to the outside by means of adjusting screws.

The transfer drum according to FIGS. 1 and 2 essentially consists of two main parts, namely the drum base body 1 and the hollow body 2. The drum base body 1 is firmly attached to the axis 3, on the free cylinder journal 4 and 5 of which the hollow body 2 has a sliding ring 6 is rotatably mounted.

The drum base body 1 is provided with two diametrically opposed sheet carrier combs 7, each of which is equipped on one side with comb carriers 8 arranged in the manner of a comb and on its other side with a device 9 for detecting the leading edge of the sheet.

The hollow body 2 is provided in the same way with diametrically opposed arch support combs 10 which have arch supports 11 on the side facing the adjacent arch support comb 7, which are arranged like a comb and on their other side carry a device 12 for detecting the trailing edge of the arch.

In the two bearing hubs 13 of the hollow body, the slide rings 6 already mentioned are attached by means of a press fit; in addition, four adjusting screws 14, which act on the slide ring 6, are screwed into each bearing hub 13 evenly distributed over the circumference.

In each case an arch support comb 7 and an arch support comb 10 together form an arch support surface 15. By displacing the hollow body 2 about the axis 3, they can be arranged offset with respect to one another ten arch supports 8 and 11 are pushed into one another or into their outer position according to FIG. 1. The position of the arch carrier combs 7 and 10 shown in FIG. 1 corresponds to the largest arch format.

Figures 3, 4 and 5 show the special arrangement of the bearing of the hollow body 2. As already mentioned, the slide ring 6 is fastened in the bearing hub 13 by means of a tight fit. A clearance 18 of 0.05 mm, for example, is provided between the inner surface 16 of the slide ring and the running surface 17 of the cylinder pins 4 and 5, respectively.

After loosening the lock nuts 19, all adjusting screws 14 are screwed into the position according to FIG. 4. The slide ring 6 is deformed in the manner shown. The result is a local pushing out of the game. The cylinder pins 4 and 5 are now set without play. The lock nuts 19 are tightened again.

In this setting, the transfer drum is installed in the perfecting machine.

If duplication occurs due to the above-mentioned errors in the printing of the perfecting machine, the hollow body can be adjusted radially by a maximum of the entire play, one arch support 11 being lowered and the opposite arch support 11 being raised radially outwards. FIG. 5 shows the corresponding setting of the adjusting screws 14 and the slide ring 6. The adjusting screw 14, which is located at the bottom or at the top in FIG. 5, remained unaffected by the setting in the illustrated case. Only the left adjusting screw 14 was screwed out for the entire game and the right adjusting screw 14 for the entire game. The result is a corresponding eccentric displacement of the hollow body 2 around the game 18. Of course, if necessary, the hollow body 2 could also have the same game 18 can be shifted eccentrically using the upper and lower set screws.

The adjustment of the arch carrier combs 10 of the hollow body 2 is sufficient to completely eliminate the rhythmic duplication phenomena that have occurred.

Figures 6 and 7 show a transfer drum with two arch support surfaces 15, in which two groups of arch support segments 20 and 21 are threaded on the axis, in such a way that the arch support segments 20 and 21 alternate. The arch support segments 20 are firmly attached to the axis 3 and are combined to form arch support combs 7 by means of diametrically opposite devices 9 for detecting the front edge of the arch.

The other arch support segments 21 are likewise connected to one another, specifically by means 12 for detecting the trailing edge of the arch. The arch support segments 21 thus form the two diametrically opposite arch support combs 10.

Since all arch support segments 21 are mounted such that they can be adjusted about the axis 3, the arch supports 8 and 11 of the arch support surfaces 15 can be pushed into one another or into the position shown.

As can be seen in FIG. 7, the bearing hubs 13 of four arch support segments 21, which are arranged at a certain distance from one another, are each rotatably arranged on the axis 3 via a sliding ring 6. The bearing hubs 13 of these arch support segments 21 have the previously mentioned set screws 14 symmetrical to the circumference. The design of the bearing of all four arch support segments 21 equipped with set screws 14 corresponds entirely to that shown in FIGS. 3, 4 and 5. The four arch support segments 21 provided with set screws 14 can therefore be adjusted radially if required. Since the remaining arch support segments 21 are supported with a certain play and are connected to one another overall via the device 12 for detecting the trailing edge of the arch, the adjustment has an effect on the entire arch support comb 10. Even with a transfer drum, which is composed of individual arch support segments 20, 21, there is thus the possibility of compensating for shape and concentricity errors by adjusting some arch support segments 21 according to the invention. Of course, all adjustable arch support segments 21 can be mounted on the axis 3 via a slide ring 6 with the aid of set screws 14.

The sheet transfer drum shown in FIG. 8 with two sheet support surfaces 15 is similar in structure to that shown in FIGS. 1 and 2. Here, too, a drum base body 1 is fixed on the axis 3, while the hollow body 2 is mounted so as to be adjustable about the axis 3. The compensation of a possible concentricity or shape error is not, however, carried out by adjustment measures on the mounting of the hollow body 2, but parts of the arch support surface 15 itself are designed to be radially adjustable.

In the two diametrically opposed arch carrier combs 10 of the hollow body 2, the two devices 12 for grasping the trailing edge of the arch have radially adjustable adjusting blocks 22 in front of them.

During the installation of the transfer drum according to FIG. 8, the sheet guiding surface 23 of the blocks 22 is at the same height as the sheet support 15. However, if a runout error is found in the imprint, this can be remedied by placing one of the blocks 22 radially in this way is adjusted so that its sheet guiding surface 23 is higher than the sheet support surface 15. By such a simple measure, the incorrect position of the print end can be corrected with low concentricity errors.

FIG. 9 also shows a basic structure of the transfer drum, as has already been described with reference to FIGS. 1 and 2. However, 15 adjustment options are provided neither on the two bearings of the hollow body 2 nor in its arch support surface. Rather, a set screw 24 is screwed into the arch carrier combs 10 at the level of each arch carrier 11 in such a way that its free end 25 abuts against a stop 26 which is provided at the end of the arch carrier 11 on the inner edge 27 thereof. By unscrewing these set screws 24 from the arch support comb 10 in the direction of the end of the arch support 11, each of the arch supports 11 can be bent or deformed radially outward. This possibility of adjustment also offers an opportunity to remedy duplication phenomena which are due to form and concentricity errors or to increased play due to improper handling of the machine in operation.

Small manufacturing tolerances cannot be ruled out even with the most precise manufacture of machine parts in the order of the size of transfer drums of the type mentioned, provided that the economy of manufacture is to be preserved. The invention offers the possibility of eliminating even the smallest manufacturing inaccuracies which could still have a negative effect on the printed image.

PARTS LIST

• 1 drum base
• 2 hollow bodies
• 3 axis
• 4 cylinder pins
• 5 cylinder pins
• 6 slide ring
• 7 arch carrier combs
• 8 arch supports
• 9 Device for grasping the leading edge of the sheet
• 10 arch carrier combs
• 11 arch supports
• 12 Device for detecting the trailing edge of the sheet
• 13 bearing hubs
• 14 set screws
• 15 arch wings
• 16 inner surface of the sliding ring
• 17 cylinder journal tread
• 18 game
• 19 lock nuts
• 20 arch support segments
• 21 arch support segments
• 22 blocks
• 23 sheet guiding surface
• 24 set screws
• 25 free end
• 26 stop
• 27 inner edge

Claims (3)

1. Transfer drum for face and offset printing presses with two diametrically opposed sheet support surfaces, which are formed by two comb-like interlocking groups of sheet supports, one of the two sheet support groups of a sheet support surface having a device for detecting the front edge of the sheet and both sheet support groups forming an arc support surface to each other about the axis of rotation the transfer drum are adjustable and each arch support is also fixedly connected to a diametrically opposite arch support of the other sheet support surface and is arranged on the axis of the transfer drum,
characterized,
that some or all of the diametrically opposed and firmly connected arch supports (8 and 11) are mounted together radially adjustable. 2. transfer drum according to claim 1, in which two diametrically opposed sheet carrier groups belong to a drum base body and each of them is provided with a device for detecting the leading edge of the sheet, while the other two sheet carrier groups are arranged on a hollow body partially encompassing the drum base and one each Have means for detecting the trailing edge of the sheet, characterized in that a) that the hollow body (2) is mounted on the two cylinder pins (4, 5) provided on the drum base body (1), each via a slide ring (6), b) that between the cylinder pin (4 or 5) and slide ring (6) play (18) is provided c) and that in the hollow body (2) adjusting screws (14) are arranged, which act on the slide ring (6) and by deforming the slide ring (6) eliminate the play (18) between the inner surface of the slide ring (16) and the cylinder journal running surface (17) or radially adjust the arch support (11). 3. transfer drum according to claim 1, in which two diametrically opposed arch support groups are composed of arch support segments and each of them is provided with a device for detecting the leading edge of the sheet, while the other two arch support groups likewise consist of individual arch support segments and each have a device for detecting the trailing edge of the sheet ,
characterized, a) that some or all of the arch support segments (21) are mounted on the axle (3) via a slide ring (6), b) that play is provided between the inner surface of the slide ring (16) and the axis (3), c) and that in the arch support segments (21) provided with a slide ring (6), set screws (14) are arranged which act on the slide ring (6) and by deforming the slide ring (6) the play (18) between the slide ring inner surface (16) and remove the axle (3) locally or adjust the arch support segments (21) radially.

Images