Device and method for supporting a printing cylinder

Abstract

The invention relates to a printing unit (1) comprising a plurality of printing cylinders (2), wherein at least one printing cylinder (2) is rotatably mounted in a bearing position on a first side by means of a first bearing unit (6) and on a second side by means of a second bearing unit (7) in an operating state, wherein the first bearing unit (6) can be disengaged and, by means of an adjusting device (8), can be set aside for setup purposes and returned to the bearing position and engaged to restore the operating state. It is therefore the object of the present invention to find a solution for gently sliding the first bearing unit (6) onto the first bearing journal (4) and to prevent tilting and damage to the first bearing or the bearing seats and running surfaces of the first bearing journal (4).The problem is solved by a device in which the first bearing unit (6) and / or the adjusting device (8) comprises at least one driver (9), wherein the at least one driver (9) can be brought into contact with the associated pressure cylinder (2) at least temporarily when the first bearing unit (6) is moved into the bearing position.

Description

[0001] The invention relates to a printing unit comprising a plurality of printing cylinders, wherein at least one printing cylinder is rotatably mounted in a storage position on a first side by means of a first bearing unit and on a second side by means of a second bearing unit in an operating state, wherein the first bearing unit can be disengaged and set down for setup purposes by means of an adjusting device and can be brought back into the storage position and engaged again to establish the operating state.

[0002] Furthermore, the invention relates to a method for receiving a first bearing journal of a printing cylinder by a first bearing unit, wherein the first bearing unit, which can be moved by means of an adjusting device, is brought into a storage position in which the first bearing unit can be pushed onto the first bearing journal of the printing cylinder.

[0003] Printing units are known from the prior art in which a change of the functional surface and / or the circumference of at least one printing cylinder is possible, for example by means of printing form sleeves, sleeves for changing the transfer cylinder or sleeves of different thicknesses for changing the cylinder circumference and thus the printing length.

[0004] In this context, all cylinders used in state-of-the-art printing processes are referred to as printing cylinders. A printing cylinder can thus be designed, for example, as a printing form cylinder (also known as a plate cylinder in offset printing), a transfer cylinder (also known as a blanket cylinder in offset printing due to its covering with a printing blanket known as a rubber blanket), or even as an impression cylinder.

[0005] If such sleeve-shaped sleeves need to be replaced, this is only possible by sliding the sleeve sideways onto the corresponding printing cylinder due to the circumferentially closed sleeve.

[0006] For example, EP 2 388 141 A2 discloses a format-variable printing unit in which a plurality of printing cylinders are arranged in a spatially variable manner in order to be able to exchange or change the corresponding printing cylinders.

[0007] DE 199 37 796 A1 discloses a printing unit concept in which the printing cylinders are mounted in linear guides so that they can be adjusted relative to one another, so that if the cylinder diameter changes, the distance between the cylinders can be adjusted.

[0008] In the printing units known from the prior art, a printing cylinder is mounted on both sides, i.e. on both sides of the functional surface. With such double-sided mounting, which is particularly necessary for medium and larger web widths to achieve print quality, a printing cylinder comprises a second bearing journal on its second side, on which a second bearing, usually a roller bearing, is arranged. The second bearing is arranged in a second bearing unit. The second bearing unit can, for example, be the side wall or be arranged in the side wall if the spatial position of the printing cylinder is not to be changed or is to be changed only slightly. Whereas in spatially adjustable printing cylinders the second bearing unit is arranged so that it can be spatially adjusted relative to the side wall.Such a printing cylinder further comprises, on its first side, a first bearing journal, which is mounted in a first bearing unit, which is usually also designed as a rolling bearing. The first bearing unit comprises both the corresponding rolling bearing and a receptacle for this bearing.

[0009] In order to replace the packing or a closed sleeve on the printing cylinder, the first bearing unit must be removed in front of the printing cylinder, viewed in the direction of the longitudinal axis of the printing cylinder, which is also referred to as disengaging the first bearing unit. To do this, for example, the first bearing unit is pulled from the first bearing journal of the printing cylinder in the longitudinal direction of the printing cylinder and then the first bearing unit is moved by means of an adjusting device in a plane perpendicular to the longitudinal axis of the printing cylinder so that the printing cylinder is accessible in the direction of its longitudinal axis, thus enabling the printing cylinder to be retooled. While the first bearing unit is moved away from the printing cylinder, the printing cylinder is usually held exclusively in the second bearing unit. It is also possible for the printing cylinder to be additionally supported in addition to the second bearing unit.

[0010] After the conversion process, such as changing a sleeve on the printing cylinder, the printing cylinder must be stored again in the first bearing unit. For this purpose, the first bearing unit, if necessary with the first bearing installed therein, is moved to the original position so that the first bearing unit is then pushed onto the first bearing of the printing cylinder in the direction of the longitudinal axis of the printing cylinder.

[0011] However, particularly with very long printing cylinders and / or very slim printing cylinders, the problem arises that due to the unavoidable bending of the printing cylinder and / or the bearing play in the second bearing unit required for function and service life, the position of the first bearing journal after removal of the first bearing unit deviates slightly from its original position when supported on both sides, which can lead to problems when sliding the first bearing unit onto the first bearing journal, such as canting or the risk of damage to the running surfaces of the first bearing.

[0012] It is therefore the object of the present invention to find a solution for gently sliding the first bearing unit onto the first bearing journal and to avoid tilting and damaging the first bearing or the bearing seats and running surfaces of the first bearing journal.

[0013] The present object is achieved by a device according to claim 1 and by a method according to claim 11.

[0014] The object is achieved by a device in which the first bearing unit and / or the adjusting device comprises at least one driver, wherein the at least one driver can be brought at least temporarily into contact with the associated printing cylinder when the first bearing unit is moved into the storage position.

[0015] The object is achieved by a method in which, when the first bearing unit is moved into the storage position, the printing cylinder is at least temporarily supported by at least one driver attached to the adjusting device and / or to the first bearing unit.

[0016] These solutions have the advantage that with very little technical effort, without additional control technology effort and regardless of the extent of the displacement of the first bearing journal of the printing cylinder, the printing cylinder is brought into a position in which the first bearing unit can be pushed onto the first bearing journal of the printing cylinder without the risk of tilting and without the risk of damage.

[0017] According to one embodiment of the invention, the at least one driver is arranged in a non-contact manner with the printing cylinder during operation, meaning that the driver is not in contact with the printing cylinder during operation. This embodiment has the advantage that no wear can occur on the printing cylinder and the at least one driver, and that no interference factors can occur during printing.

[0018] According to a further embodiment of the invention, the adjustment device performs a linear or pivoting movement. The solution according to the invention can thus be implemented in all known variable-format printing units, regardless of the adjustment movement of the first bearing unit and / or the corresponding printing cylinder.

[0019] According to a further embodiment of the invention, the at least one driver is designed to be immobile. This embodiment, according to which the at least one driver is immobile and thus statically attached to the first bearing unit or to the adjustment device, offers the advantage of a technically simple, maintenance-free, and consequently very cost-effective solution.

[0020] According to a further embodiment of the invention, the at least one driver is designed to be movable. Although this embodiment requires a somewhat more technically complex solution, it allows the driver to be moved into a position in which the first bearing journal of the printing cylinder is very precisely aligned with the first bearing unit. After the first bearing unit has been pushed onto the first bearing journal, the at least one driver can be moved away from the printing cylinder, so that there is no longer any contact between the at least one driver and the printing cylinder.

[0021] According to a further embodiment of the invention, the at least one driver is designed as a stud bolt and / or has the structure of a ring segment. This embodiment offers the advantage of a very cost-effective and technically easy-to-retrofit solution.

[0022] According to a further embodiment of the invention, the at least one driver comprises a rotatable element, such as a rotatably mounted sleeve or a roller bearing, which is at least temporarily in contact with the printing cylinder. Such a configuration has the advantage that, upon contact of the at least one driver with the printing cylinder, a rotational movement of the printing cylinder is possible without impairments such as friction or wear.

[0023] Preferred developments of the invention will become apparent from the dependent claims and the following description. Various embodiments of the invention are explained in more detail, without being limited thereto, with reference to the drawings. Herein: Fig. 1A basic structure of an exemplary printing unit Fig. 2A basic structure of a printing cylinder including bearings on both sides Fig. 3A printing cylinder with a parked first bearing unit Fig. 4A printing cylinder mounted in the second bearing unit with corresponding bearing play Fig. 5A printing cylinder with a driver in contact Fig. 6A printing cylinder immediately before sliding the first bearing unit Fig. 7A printing cylinder after sliding the first bearing unit onto the first bearing journal Fig. 8An exemplary design of the driver Fig. 9Another exemplary design of the driver

[0024] Fig. 1shows the basic structure of an exemplary printing unit 1. This comprises a plurality of printing cylinders 2 arranged essentially one above the other, with the printing material web 9 running between two printing cylinders 2. In the case of the printing unit 1 being designed as an offset printing unit for single-sided printing of the substrate web 9, the upper printing cylinder 2, which is in contact with the forme rollers arranged above, is designed as a plate cylinder, whereas the middle printing cylinder 2 is designed as a transfer cylinder, which is also referred to as a blanket cylinder. The lowest printing cylinder 2 shown is designed as an impression cylinder in an offset printing unit.However, since the present invention is applicable to all corresponding printing cylinders 2 regardless of the design of the printing cylinders 2, the term “printing cylinder 2” is used hereinafter exclusively for all such printing cylinders 2 which, in a modified form, are also used in printing units 1 for other printing processes.

[0025] If the section length is to be changed in so-called format-variable printing units 1, the diameters and thus the circumferences of the corresponding printing cylinders 2 are exchanged. Fig. 1In the example shown, the diameters of the upper printing cylinder 2 and the middle printing cylinder 2 would be changed by swapping the sleeves 10 attached to the corresponding printing cylinders 2. Due to the closed outer surface of such sleeves 10, these sleeves 10 can only be removed from the front of a corresponding printing cylinder 2. Due to the variable diameters of such printing cylinders 2, either these diameter-adjustable printing cylinders 2 and / or the adjacent printing cylinders 2 are mounted accordingly in an adjustable manner. This can be achieved, for example, by the relevant printing cylinder(s) 2 being adjustably mounted in or on levers.

[0026] In the Fig. 1In the example shown, the middle pressure cylinder 2 is mounted on the upper pivoting lever, which serves as the adjusting device 8, and is adjusted during the pivoting movement of the adjusting device 8, symbolized by a curved arrow. Fig. 1 In the example shown, the lower pressure cylinder 2 is mounted in the lower adjustment device 8 for linear movement and can thus be adjusted in its position. However, the adjustment device 8 can be designed in any desired manner, namely as a pivotable lever, as two levers pivotable relative to one another, and / or as an adjustment device 8 mounted in a linear guide.

[0027] The upper printing cylinder 2, designed as a forme cylinder, can, for example, be arranged at least on one side in the Fig. 1 be mounted on a side wall not shown in the drawing, provided that this pressure cylinder 2 does not have to be spatially changed or only slightly changed in its position.

[0028] Fig. 2shows the top view of an exemplary bearing of any printing cylinder 2, on which a sleeve 10 is mounted. The cylinder 2 is mounted so as to be rotatable about its longitudinal axis 13. For this purpose, the printing cylinder 2 comprises a first bearing journal 4, wherein the first bearing journal 4 is mounted in a first bearing unit 6. The first bearing unit 6 comprises both the bearing, which is usually designed as a rolling bearing, and the associated housing in which the bearing is held. Since it is completely irrelevant for the present invention whether and how the bearing is arranged in the bearing housing, the term first bearing unit 6 is used exclusively below, this term comprising the bearing and the housing in which the bearing is arranged. It is also possible for the bearing to be split, so that the inner ring of the bearing is mounted on the first bearing journal 4, whereas the rolling elements and the outer ring remain in the housing.Even in such a case, due to a lack of relevance to the present invention, only the terms first bearing journal 4 and first bearing unit 6 are used.

[0029] The first bearing unit 6 is connected to an adjustment device 8, which can be designed, for example, as a pivotable lever or as a linearly movable element. The adjustment device 8 serves to change the position of the first bearing unit 6 in a substantially stationary printing cylinder 2, in order to enable a replacement of the sleeve 10.

[0030] In the case of a variably mounted printing cylinder 2, the adjustment device 8 serves both to park the first bearing unit 6, for example to change the sleeve 10, and to change the spatial position of the printing cylinder 2 when the first bearing unit 6 is mounted on the printing cylinder 2, in order to be able to change the position of the printing cylinder 2 required for printing when the sleeves 10 have different thicknesses.

[0031] In the Fig. 2 The printing cylinder 2 shown as an example comprises, on the side facing away from the first bearing pin 4, a second bearing pin 5, on which the printing cylinder 2 is rotatably mounted in a second bearing unit 7. In the case of the Fig. 2 as well as in the Figures 3 to 7In the printing cylinder 2 shown as an example, the second bearing unit 7 is installed in a fixed position in the side wall 11, whereby it should be noted at this point that the second bearing unit 7 can also be designed to be movable, for example if the printing cylinder 2 has to be changed in its spatial position relative to the other printing cylinders 2 in order to adapt to sleeves 10 of different thicknesses for printing.

[0032] The Fig. 2 The position of the first bearing unit 6 shown is referred to as the bearing position, since the printing cylinder 2 is stably mounted and the first bearing unit 6 is aligned with the second bearing unit 7.

[0033] Fig. 3 shows a state of the printing cylinder 2 from Fig. 2, in which the first bearing unit 6 is positioned away from the front side of the bearing. For this purpose, the first bearing unit 6 is first pulled away from the first bearing seat by the length a in the axial direction and thus in the direction of the longitudinal axis 13 of the printing cylinder 2, so that the first bearing is no longer seated on the first bearing seat 4. This process is also referred to as disengaging the first bearing seat 6. After the first bearing unit 6 has been pulled away from the first bearing journal 4 in the axial direction, the first bearing unit 6 is moved by the distance y in a direction perpendicular to the longitudinal axis 13 of the printing cylinder 2, so that the front side of the printing cylinder 2 is no longer covered by the first bearing unit 6. In this state, the first bearing unit 6 is in a sleeve change position, since in this sleeve change position of the first bearing unit 6 the sleeve 10 can be pulled off the printing cylinder 2 or pushed onto it.

[0034] Fig. 4shows a state of the printing cylinder 2, which occurs after the first bearing unit 6 has been pivoted away and / or after a sleeve 10 has been replaced. Due to the bearing play required for operation in the second bearing unit 7, in which the printing cylinder 2 is thus exclusively held, and / or due to a possible deflection, particularly in the case of very long and very slim printing cylinders 2, the first bearing journal 4 sags downwards by the amount Δy compared to the bearing position when the first bearing unit 6 is parked, which in Fig. 4This is illustrated by the fact that the longitudinal axis 13 of the printing cylinder 2 in the region of the first bearing seat 4 is no longer located in the bearing position indicated by the dimension y, but is offset downwards by the dimension Δy. Such positional deviations of the first bearing seat 4 relative to the bearing position, which are caused by the bearing play of the second bearing unit 7 and / or by the deflection of the printing cylinder 2, are unproblematic with an appropriate bearing design, but can lead to problems when sliding the first bearing unit 6 back into the storage position.

[0035] Fig. 5 shows the printing cylinder 2 with the first bearing unit 6 parked, wherein the first bearing unit 6 is opposite the one shown in Fig. 3 and Fig. 4 shown position has been adjusted essentially by the amount y-Δy in the direction perpendicular to the longitudinal axis 13 of the printing cylinder 2, and thus has not yet reached the height of the storage position.

[0036] As from Fig. 5 As can be seen, the Fig. 5 In the example shown, the adjusting device 8 has a driver 9 which is designed in such a way that this driver 9 can be brought into contact with the corresponding associated pressure cylinder 2 at least temporarily when the first storage unit 6 is moved into the storage position, that is to say when the first storage unit 6 reaches a position shortly before the height of the storage position, in order to be able to raise it essentially by the amount Δy.

[0037] Although in Fig. 5 an embodiment is shown in which the driver 9 is fastened to the adjusting device 8, such as a swivel arm or a displacement device displaceably arranged on a linear guide, it is also possible to fasten the driver 9 to the first bearing unit 6.

[0038] Fig. 5shows an embodiment in which only one driver 9 is arranged on the adjusting device 8. However, it is also possible to attach a plurality of drivers 9, such as a plurality of stud bolts or elements fastened to stud bolts, to the adjusting device 8 and / or to the first bearing unit 6.

[0039] Fig. 6 shows the printing cylinder 2 from Fig. 5 , the first bearing unit 6 opposite Fig. 5 by the amount Δy perpendicular to the longitudinal axis 13, so that the printing cylinder 2 is essentially in its storage position, since the printing cylinder 2 has also been raised by the driver 9 by the amount Δy, since the printing cylinder 2 is supported at least during this period and thus temporarily on the driver 9. In the Figures 4 to 7In the example shown, the pressure cylinder 2 is in contact with the driver 9 in the area of ​​its pin 3, but it is arbitrary where the pressure cylinder 2 is supported on the driver 9.

[0040] As from Fig. 6 As can be seen, by supporting the printing cylinder 2 on the driver 9, the longitudinal axis 13 of the printing cylinder 2 and the first bearing unit 6 are again in alignment, which is sufficient to allow the first bearing unit 6 to be pushed onto the first bearing journal 4 without tilting and without damaging the bearing of the first bearing unit 6 or the first bearing seat 4.

[0041] Fig. 7 shows the printing cylinder 2 from Fig. 6 , whereby in Fig. 7In the state shown, the first bearing unit 6 has been pushed completely onto the first bearing journal 4 and thus fully re-engaged, so that the driver 9 has also been moved on the journal 3 in the direction of the second bearing journal 5, since the driver 9 engages the printing cylinder 2 on the journal 3 and supports it there. The printing cylinder 2 is thus again fully supported by the first bearing unit 6 and the second bearing unit 7 and is therefore ready for operation.

[0042] In the Fig. 7In the state shown, the printing cylinder 2 is in an operating state, since the printing cylinder 2 is in the storage position, is fully supported and is therefore basically ready for operation. In this case, the driver 9 can either still be in contact with the printing cylinder 2, preferably with a pin 3 of the driver 9. However, it is advantageous if, in this operating state, the driver 9 is arranged so as not to make contact with the printing cylinder 2 or the pin 3 of the printing cylinder 2, which is achieved, for example, by there being a small gap of, for example, a few tenths of a millimeter between the driver 9 and the printing cylinder 2.While such a gap means that the printing cylinder 2 is not exactly in the bearing position before the second bearing unit 7 engages the first bearing journal 4, such minor deviations do not lead to any problems or damage when sliding the first bearing unit 6 onto the first bearing journal 4, especially if the first bearing journal 4 has a bevel or chamfer. Rather, such a contact-free arrangement of the driver 9 to the printing cylinder 2 offers the advantage of zero wear and the avoidance of other potential problems such as oscillations or vibrations.

[0043] The driver 9 can be designed either as a movable or a fixed device. A fixed device has the advantage of enabling a simple and cost-effective design; however, the printing cylinder 2 is not exactly in its bearing position before the first bearing unit 6 is pushed onto the first bearing journal 4, provided the driver 9 is arranged without contact with the printing cylinder 2 in the operating state.

[0044] However, if the required tolerances of the first bearing require exact alignment of the longitudinal axis 13 of the printing cylinder 2 with the first bearing unit 6, it is also possible to make the driver 9 movable. For example, the driver 9 can be adjusted or pivoted toward the printing cylinder 2 to temporarily raise the printing cylinder 2 when the first bearing unit 6 is moved into the engaged position, so that after the second bearing unit 7 is pushed on, at least one driver 9 is moved away from the printing cylinder 2 or pivoted away again in order to be arranged without contact with the printing cylinder 2 in the operating state.

[0045] Although not in the Figures 4 to 7shown, it is also possible, additionally or alternatively, to adjust the driver 9 in the extension of the longitudinal axis 13 of the printing cylinder 2, so that the required area for at least temporarily supporting the driver 9 on the printing cylinder 2 is reduced, so that this in the extension of the longitudinal axis 13 is smaller than the adjustment movement of the first bearing unit 6 in the extension of the longitudinal axis 13.

[0046] Fig. 8shows an exemplary embodiment of a driver 9, in which the driver 9 has the contour of a ring segment, so that secure support of the printing cylinder 2 or a pin 3 of the printing cylinder 2 on the driver 9 is possible. The ring-segment-shaped driver 9 can be fastened, for example, by means of stud bolts to the adjustment device 8 and / or to the first bearing device 6. However, it is also possible to design the driver 9 as at least one stud bolt, which supports the printing cylinder 2 when it is moved into the storage position.

[0047] Fig. 9 shows an exemplary embodiment in which the driver 9 is designed in two parts and has a substantially V-shaped contour, so that the printing cylinder 2 or a pin 3 of the printing cylinder 2, which can be a forme cylinder or a transfer cylinder, can assume a stable position therein when supported.

[0048] The contour of the at least one driver 9 can in principle be selected as desired, provided that it enables secure support of the printing cylinder 2, which depends in particular on whether the adjusting device 8 and thus also the first bearing unit 6 attached thereto executes a linear or circular arc-shaped movement.

[0049] The driver 9 can in principle be made of any dimensionally stable material, preferably the driver 9 is made of metal, plastic or a composite material.

[0050] Although not in the Figures 8 and 9As shown, it is also possible for the driver 9 to comprise at least one rotatable element, such as a rotatably mounted disc, a rotatably mounted ring, or a roller bearing, wherein the rotatable element is brought into operative connection with the printing cylinder 2. Thus, it is possible for the printing cylinder 2 to be set in rotation while the first bearing unit 6 is being pushed onto the first bearing journal 4 in order to enable easier engagement of the first bearing unit 6. List of reference symbols

[0051] 1Printing unit 2Printing cylinder 3Pivot 4First bearing pin 5Second bearing pin 6First bearing unit 7Second bearing unit 8Adjustment device 9Carrier 10Sleeve 11Side wall 12Track 13Longitudinal axis

Claims

1. Printing unit (1) comprising a plurality of printing cylinders (2), wherein at least one printing cylinder (2) is rotatably mounted in a storage position on a first side by means of a first bearing unit (6) and on a second side by means of a second bearing unit (7) in an operating state, wherein the first bearing unit (6) can be disengaged and set aside for setup purposes by means of an adjusting device (8) and can be set and re-engaged into the storage position to establish the operating state, characterized in that the first bearing unit (6) and / or the adjusting device (8) comprises at least one driver (9), wherein the at least one driver (9) can be brought at least temporarily into contact with the associated printing cylinder (2) when the first bearing unit (6) is moved into the storage position.

2. Printing unit (1) according to claim 1, characterized in that the at least one driver (9) is arranged in the operating state without contact with the printing cylinder (2).

3. Printing unit (1) according to one of claims 1 or 2, characterized in that the adjusting device (8) performs a linear movement or a pivoting movement.

4. Printing unit (1) according to one of claims 1 to 3, characterized in that at least one driver (9) is designed to be immovable.

5. Printing unit (1) according to one of claims 1 to 3, characterized in that at least one driver (9) is designed to be movable.

6. Printing unit (1) according to one of claims 1 to 5, characterized in that the at least one driver (9) is designed as at least one stud bolt and / or has a contour of a ring segment.

7. Printing unit (1) according to one of claims 1 to 5, characterized in that the at least one driver (9) comprises at least one rotatable element.

8. Printing unit (1) according to one of claims 1 to 7, characterized in that at least one driver (9) engages a pin (3) of the printing cylinder (2).

9. Printing unit (1) according to one of claims 1 to 8, characterized in that the driver (9) is made of metal, plastic or a composite material.

10. Printing unit (1) according to one of claims 1 to 9, characterized in that the printing cylinder (2) is a forme cylinder or a transfer cylinder.

11. Method for receiving a first bearing journal (4) of a printing cylinder (2) by a first bearing unit (6), wherein the first bearing unit (6) which is movable by means of an adjusting device (8) is brought into a storage position in which the first bearing unit (6) can be pushed onto the first bearing journal (4) of the printing cylinder (2), characterized in that when the first bearing unit (6) is moved into the storage position, the printing cylinder (2) is at least temporarily supported by at least one driver (9) attached to the adjusting device (8) and / or to the first bearing unit (6).

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