This application claims the priority of German Patent Document No. DE 10 2013 102 729.6, filed Mar. 18, 2013, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a folding device of a printing press. The invention furthermore relates to a method for operating the folding device.
From practice, folding devices of printing presses with the help of which transverse folds and/or longitudinal folds can be formed on signatures which are severed from a printed, in particular web-like, substrate are already known. Here, pin-type folding devices and gripper-type folding devices are distinguished in principle, namely dependent on whether so-called folding knife cylinders of the folding devices utilize pins or grippers for position fixing of the signatures to be folded on the folding knife cylinder. From practice it is likewise already known to collect multiple signatures into a signature stack during the folding of the signatures.
From DE 44 26 987 A1 a folding device of a printing press with multiple cylinders is known, namely with a cutting cylinder, a pin and folding knife cylinder, a folding jaw cylinder and a gripper and folding knife cylinder. By way of the cutting cylinder, signatures can be severed from the printed substrate. Between the pin and folding knife cylinder and the folding jaw cylinder, first transverse folds can be formed on the signatures and between the folding jaw cylinder and the gripper and folding knife cylinder, two transverse folds can be formed on the signatures.
From DE 44 26 987 A1 it is known furthermore that the pin and folding knife cylinder, the folding jaw cylinder and the gripper and folding knife cylinder each consists of two cylinder bodies or cylinder segments that can be twisted relative to one another. Thus, the relative position of the cylinder bodies of the pin and folding knife cylinder, the relative position of the cylinder bodies of the folding jaw cylinder and the relative position of the cylinder bodies of the gripper and folding knife cylinder is variable in order to change a cut-of and/or a positive overlap setting.
Thus it is possible according to this prior art to change the circumferential distance between the pins which are assigned to a first cylinder body of the pin and folding knife cylinder and the folding knives which are assigned to a second cylinder body of the pin and folding knife cylinder by twisting the cylinder segments of the same. On the folding jaw cylinder, the circumferential relative position between folding jaws which are assigned to the first cylinder body of the folding jaw cylinder and which are involved in the forming of the first transverse fold and the folding jaws which are assigned to the second cylinder body of the folding jaw cylinder and which are involved in the forming of the second transverse fold is variable by twisting the cylinder body of the same. In the region of the gripper and folding knife cylinder, the circumferential distance between the grippers which are assigned to the first cylinder body of the gripper and folding knife cylinder and the folding knives which are assigned to the second cylinder body of the gripper and folding knife cylinder is variable by twisting the cylinder body of the same.
As explained above, a cut-off changeover, for example from parallel fold to delta fold can be performed because of this. The so-called positive overlap can also be adjusted.
In particular when with the folding device known from DE 44 26 987 A1 for the cut-off changeover and/or positive overlap changeover the cylinder bodies of the pin and folding knife cylinder, folding jaw cylinder and gripper and folding knife cylinder are twisted relative to one another, the relative position between the interacting assemblies of different cylinders remains unchanged here. Accordingly, the relative position on the one hand between the folding knives of the pin and folding knife cylinder and the folding jaws of the folding jaw cylinder which are involved in the forming of the first transverse fold on the other hand remains the same.
Starting out from this, the object of the present invention is based on creating a new type of folding device of a printing press and a method for operating the folding device.
According to the invention, the relative position between at least two interacting cylinders in the circumferential direction is variable in such a manner that the circumferential relative position of assemblies which interact during the folding and are assigned to the cylinders is variable. With the invention, a folding device of a printing press is proposed for the first time, in which the circumferential relative position of different assemblies interacting during the folding and which are assigned to different cylinders is variable. Thus, for example, the circumferential relative position between folding knives of the pin and folding knife cylinder and folding jaws of a folding jaw cylinder is variable. Likewise, the circumferential relative position between folding knives of the gripper and folding knife cylinder and folding jaws of the folding jaw cylinder is variable. Because of this, the function of the folding device can be improved in particular when in a so-called collecting mode a multiplicity of signatures are collected on top of one another in a so-called collecting mode and forms then have to be formed on thick signature stacks. According to an advantageous further development of the invention, the circumferential relative position between the interacting assemblies of the cylinder is variable with the help of a driving system of the cylinders. Preferentially, the interacting cylinders for this purpose are coupled via helical spur gears on the drive side, wherein the circumferential relative position between the interacting assemblies of the cylinders is variable through an axial shifting of at least one of the helical spur gears. Alternatively, the interacting cylinders are coupled via spur gears and a phase shifter gearbox on the driving side, wherein the circumferential relative position between the interacting assemblies of the cylinders can then be varied through the phase shifter gearbox. Furthermore, the interacting cylinders can be alternatively driven via individual drives, wherein the circumferential relative position between the interacting assemblies of the cylinders can then be varied through the individual drives.
Changing the circumferential relative position between the interacting assemblies of the cylinders with the help of the driving system of the cylinders is particularly simple and therefore advantageous. Particularly preferred is a configuration of the invention, in which the cylinders of the folding device are coupled on the driving side via helical spur gears, wherein through axial shifting of at least one of the helical spur gears the circumferential relative position of the respective assemblies of the cylinders which are involved during the folding can then be varied.
According to an advantageous further development of the invention, the circumferential relative position between the folding knives which are assigned to the, or each, folding knife cylinder and folding jaws which are assigned to the folding jaw cylinder and which interact with the folding knives is variable in particular in such a manner that each folding knife, adjustable to the product thickness with respect to the distance from a folding jaw, can be introduced into an opened folding jaw preferentially in the middle.
With this configuration of the invention a bending of the folding knife or of the folding jaw when forming the fold can be counteracted in particular when a multiplicity of signatures are collected on top of one another into a thick signature stack since even with a thick signature stack the respective folding knife can then always be introduced respect to the product thickness optimal position into the respective opened folding jaws preferentially in the middle, independently of the set maximum opening of the folding jaws.
Preferred further developments of the invention are obtained from the following description. Exemplary embodiments of the invention are explained in more detail with the help of the drawings without being restricted to these.
The present invention relates to a folding device and to a method for operating such a folding device.
This function principle can also be transferred to gripper folding units.
In order to be able to optimally utilize the folding devices 10 for different product thicknesses, but the adjusting travel of the moveable folding strip 21 or folding strips 21 however being predetermined because of the control elements and being limited as a rule, the maximum opening of the folding jaw 19 or folding jaws 19 can be variably set with suitable embodiment.
The folding device 10 of
Thus it is evident from
For forming a second transverse fold on a signature 16 between the folding jaw cylinder 13 and the gripper and folding knife cylinder 22, a gripper 24 of the gripper and folding knife cylinder 22 grips a signature provided with a first transverse fold in the region of the first transverse fold, wherein the folding knife 23 of the gripper and folding knife cylinder 22 presses this signature 16 into an opened folding jaw 19b of the folding jaw cylinder 13 subject to forming a second transverse fold on the signature 16.
In the exemplary embodiment of
In an analogous manner, the gripper and folding knife cylinder 22 is also formed of two cylinder bodies, wherein a first cylinder body of the same carries the grippers 24 and a second cylinder body of the same carries the folding knives 23, the circumferential distance of which is variable by twisting the cylinder bodies of the gripper and folding knife cylinder 22.
This is also evident from
Furthermore,
The gear 31 which is assigned to the cylinder body 25 of the pin and folding knife cylinder 12 is in engagement with a gear 31 in a further gear plane, which is assigned to the cutting cylinder 11. In a further gear plane, further gears 31 are in engagement, namely the gear which is assigned to the cylinder body 28 of the folding jaw cylinder 13 and the gear 31 of the gripper and folding knife cylinder 22 which is assigned to the cylinder body 30.
For the cut-off changeover and/or positive overlap changeover in the region of the cylinders 12, 13 and 22, the respective cylinder bodies 25, 26 and 27, 28 and 29, 30 respectively are twisted relative to one another, this being carried out by driving the gears 32, 33. With such a cut-off changeover or positive overlap changeover, the cylinder bodies 25 and 26 can be twisted relative to one another in the region of the pin and folding knife cylinder 12 in order to set the circumferential distance between the pins 17 and the folding knives 18. In the region of the folding jaw cylinder 13, the cylinder bodies 27 and 28 can be twisted relative to one another in order to change the distance between the folding jaws 19a and 19b. In the region of the gripper and folding knife cylinder 22, the cylinder bodies 29 and 30 can be twisted relative to one another in order to set the circumferential distance between the grippers 24 and the folding knives 23.
According to the prior art, this twisting during the cut-off changeover and/or positive overlap changeover is effected in such a manner that the relative position between the assemblies assigned to the different cylinders and interacting during the folding remains unchanged. Accordingly, the circumferential relative position between the folding knives 18 of the folding knife cylinder 12 and the folding jaws 19a of the folding jaw cylinder 13 and the folding jaws 19b of the folding jaw cylinder 13 and the folding knives 23 of the gripper and folding knife cylinder 22 remains unchanged according to the prior art.
In terms of the present invention the relative position of at least two interacting cylinders of the folding device 10 is variable in the circumferential direction in such a manner that the circumferential relative position of the assemblies assigned to the different cylinders which interact during the folding is variable. The circumferential relative position between the assemblies of the different cylinders which interact during the folding can be preferentially varied with the help of the drive system of the cylinders.
Thus it is possible in the exemplary embodiments of
Thus,
As already mentioned, the folding knife cylinder 12, which carries the folding knives 18, in the exemplary embodiment of
In the exemplary embodiment of
To this end, as already explained in connection with
Changing the circumferential relative position between the folding jaws 19b of the folding jaw cylinder 13 and the folding knives 23 of the gripper and folding knife cylinder 22 can be effected by twisting the cylinder body 30 of the gripper and folding knife cylinder 22 carrying the folding knives 23 and/or by twisting the cylinder body 28 of the folding jaw cylinder 13 carrying the folding jaws 19b.
With the folding device 10 of
Furthermore, the circumferential relative position between the cutting knives 15 of the cutting cylinder 11 and a cutting bar system 40, which in the shown exemplary embodiments of
Accordingly, the object of the present invention is to twist assemblies on a folding device 10 which are assigned to different cylinders of the folding device 10 and which interact during the folding with respect to their circumferential relative position. Thus, the circumferential relative position between the folding knives and folding jaws which are assigned to the different cylinders is preferentially varied in order to ensure a preferentially middle dipping of the respective folding knife into the respective folding jaw even during the transverse folding of thick signature stacks and the wide opening of the folding jaws which is required for this purpose. This change of the circumferential relative position of assemblies assigned to different cylinders and interacting during the folding is entirely different from the twisting of the cylinder bodies of a cylinder which takes place during the cut-off changeover and/or positive overlap changeover.
As already explained, the changing of the circumferential relative position between the assemblies of different cylinders of the folding device which interact during the folding is carried out preferentially with the help of a driving system of the cylinders involved, wherein according to
According to a first advantageous configuration of the invention it is proposed to couple the respective interacting cylinders, i.e., in
This axial adjustment of a helical spur gear and thus the adjustment of the circumferential relative position between the assemblies of the different cylinders which interact during the folding can take place in steps or alternatively continuously.
The axially shiftable gear or spur gear 31 of the folding jaw cylinder 13 in this case is assembled of two segments, namely of a radially inner segment 41 and a radially outer segment 42, wherein the radially inner segment 41 of the helical gear or spur gear 31 is clamped and thus axially non-shiftably mounted on the shaft of the folding jaw cylinder 13 with the help of clamping rings 43, and wherein the radially outer segment 42 of the helical gear or spur gear 31 is axially shiftably guided on the radially inner segment 41 according to the arrow 44, namely via a splined profiling 45 which is shown in the cross section C of
The axial shifting of the helical gear 31 or of the outer segment 42 of the same is effected with the help of pneumatic cylinders 45 in the exemplary embodiment of
By way of the axial repositioning of the radially outer segment 42 of the gear 31 of the folding jaw cylinder 13 relative to the helical gear 31 of the folding knife cylinder 12, which is assigned to the cylinder body 26 of the folding knife cylinder 12, which carries the folding knives 18, described above, the circumferential relative position of the cylinder body 26 of the folding knife cylinder 12 is variable relative to the folding jaw cylinder 13 and thus the circumferential position of the folding knives 18 of the folding knife cylinder 12 relative to the folding jaws 19, 19a of the folding jaw cylinder 13, namely in such a manner that each folding knife 18 during the operation dips into a folding jaw with respect to the product thickness optimal position, preferentially in the middle, which folding jaw during the operation can be adjusted variably or variably wide.
It is pointed out here that the axial repositioning of helical gears for changing the circumferential relative position of assemblies of different cylinders of the folding device which interact during the folding is preferred but that this change of the circumferential relative position can also be brought about in another way. Thus, interacting cylinders can be coupled via spur gears or gears and a phase shifter gearbox, wherein the change of the circumferential relative position between the assemblies which are assigned to the different cylinders and which interact during the folding can then be varied through the phase shifter gearbox. It is also possible to drive the cylinders of the folding device via individual drives, wherein the changing of the circumferential relative position between the assemblies of the different cylinders which interact during the folding can then be varied through the individual drives. As already explained, the circumferential relative position between the assemblies which interact during the folding and which are assigned to different cylinders is variable continuously or in steps.
The invention furthermore relates to a method for operating such a folding device, wherein during the operation the circumferential relative position of at least two cylinders or of assemblies which are assigned to at least two cylinders and which interact during the folding is varied, namely preferentially in such a manner that the circumferential relative position of folding knives of one or multiple folding knife cylinders to the folding jaws of a folding jaw cylinder is varied, namely in particular in such a manner that each folding knife when forming a fold is introduced into an opened folding jaw in the middle. In the process, the variation of the circumferential relative position can be effected dependent on a thickness of a signature stack to be folded consisting of multiple individual signatures.
The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.
Number | Date | Country | Kind |
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10 2013 102 729.6 | Mar 2013 | DE | national |