The invention relates to a sheet-processing machine, in particular a rotary press, containing at least one processing station in the form of a printing unit, a stacking station for holding a stack formed from processed sheets, a delivery with an endless conveyor transporting the processed sheets in the direction of the stack, after-grippers which follow an after-gripper path during operation and which take over the processed sheets from the endless conveyor and release them over the stack, a mechanism guiding the after-grippers, and a drive for actuating the mechanism.
A machine of this type is disclosed in German Patent No. 627 851. The mechanism guiding the after-grippers belonging to the delivery disclosed therein is constructed in the form of two chain drives, whose drive is provided by a gear wheel of the impression cylinder of a preceding printing unit and interposed gear wheels. For the purpose of adapting the delivery to different formats of the processed sheets, the phase angle of the chain drives has to be adjusted with respect to the machine angle setting. Furthermore, the stops provided for forming the stack for the leading edges of the sheet have to be set to a respective position corresponding to the format and precautions have to be taken that opening and closing movements of the after-grippers take place at the correct location in each case. The possible adjustment travel of the after-grippers during the phase adjustment is determined by the length of the chain runs of the mechanism. The length must therefore correspond to the maximum required adjustment travel and thus has a direct influence on the overall length of the delivery.
The trailing edges of the sheets are always deposited at one and the same location, irrespective of their format. In the case of smaller formats, that side of the stack facing an operator and pointing downstream with respect to the transport direction is moved in the direction of the printing unit and, in particular, makes access more difficult, for example for removing a proof or changing the stack.
It is accordingly an object of the invention to provide a sheet-processing rotary press with a delivery containing after-grippers that overcomes the above-mentioned disadvantages of the prior art devices of this general type, in which accessibility to the stack during the processing of sheets with a format that is smaller than the maximum processable format is not impaired.
With the foregoing and other objects in view there is provided, in accordance with the invention, a sheet-processing machine. The machine contains at least one processing station being a printing unit, a stacking station for holding a stack formed from processed sheets and disposed downstream of the printing unit, a delivery with an endless conveyor transporting the processed sheets in a direction of the stack and disposed downstream of the printing unit, and after-grippers following an after-gripper path during operation for taking over the processed sheets from the endless conveyor and releasing the processed sheets over the stack. A mechanism is provided for guiding the after-grippers. The mechanism is set to positions correlating with different formats of the processed sheets. A drive is provided for actuating the mechanism. The drive keeps the mechanism at one and the same phase angle with respect to the printing unit in each of the positions.
In order to achieve the object, provision is made for the mechanism that guides the after-grippers to be adjustable to positions which are correlated with different formats of the processed sheets, and for the drive that actuates the mechanism to keep the mechanism at one and the same phase angle with respect to the printing unit in each of the positions.
Positions correlated with the different formats of the processed sheets are in this case to be understood to include those which the mechanism assumes in the case of a respective format when the leading edges of the sheets are placed at one and the same location in order to form the stack, irrespective of the format of the sheets, so that even stacks formed from small-format sheets assume the same distance from the downstream end of the delivery as stacks formed from large-format sheets.
In accordance with an added feature of the invention, the mechanism and the drive form one structural unit disposed to be displaced with respect to the delivery.
In accordance with another feature of the invention, the endless conveyor and the mechanism have a torque-transmitting connection with each other. The torque-transmitting connection is a telescopically constructed drive shaft or a flexible drive having an endless flexible drive unit acting on the mechanism. During a change in the positions of the mechanism, the flexible drive is driven such that the mechanism is not actuated.
In accordance with an additional feature of the invention, the endless conveyor contains a first conveyor and a second conveyor. The first conveyor has and bears first gripper bars for gripping leading gripper edges of the processed sheets, and the second conveyor has and bears second gripper bars for gripping trailing gripper edges. A rotary coupling is provided and operates in a first operating state or a second operating state. In the first operating state, the rotary coupling produces a drive connection between the first conveyor and the second conveyor. In the second operating state, the rotary coupling releases the second conveyor for a phase adjustment with respect to the first conveyor. The torque-transmitting connection between the mechanism and the endless conveyor exists with the second conveyor.
In accordance with a further feature of the invention, an actuating drive is provided and has a drive connection to the second conveyor through the rotary coupling in a second operating state of rotary coupling and, in a first operating state of the rotary coupling, the actuating drive is uncoupled from the second conveyor.
In accordance with a further added feature of the invention, a further actuating device actuated rotationally is provided and has an actuating wheel for setting the positions of the mechanism. A drive connection is provided between the actuating wheel and the actuating drive.
In accordance with another further feature of the invention, the delivery has a sheet guide device that can be set to different formats of the processed sheets, and the sheet guide device has ends with clearances formed therein. The after-grippers engage in the clearances and take over the processed sheets from the endless conveyor.
In accordance with another additional feature of the invention, the sheet guide device has a stationary first guide section and a second guide section following the stationary first guide section in a direction of the stack and adjoins the stationary first guide section. The second guide section can be adjusted for accommodating different formats of the processed sheets. The first stationary first guide section and the second guide section have mutually facing end sections which inter-engage in a manner of a comb, and the clearances are formed in the second guide section.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a sheet-processing rotary press with a delivery containing after-grippers, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
The subject of the invention can be used irrespective of whether the sheet-processing machine contains a delivery whose endless conveyor clasps the sheets only at their leading edges or a delivery whose endless conveyor also clasps the trailing edges.
In the first of the aforementioned cases, in order to guide the sheets in the delivery, recourse can be had, for example, to the teaching disclosed in German Patent No. 627 851 but whose application is recommended only when the sheets are to be printed exclusively on one side.
Referring now to the figures of the drawing in detail and first, particularly, to
Although only one printing unit is indicated, it goes without saying that the machine, in its equipment for multicolor printing, contains a corresponding number of printing units, in the case of a machine equipped for recto and verso printing of one side of the sheets in each case with a specific number of colors (including black), twice the number of printing units and a turner station being provided, which transfers sheets 8, optionally turned or unturned, to a subsequent printing unit.
Instead of the printing unit 1, a finishing or post-treatment unit, such as a varnishing unit or a perforating unit, etc., can also be provided as the last processing station upstream of the delivery 2.
Moreover, it goes without saying that a feeder loading the machine with the sheets is connected upstream of a first processing station, the feeder, just like the delivery, advantageously being equipped for non-stop operation.
In order to transfer in particular the trailing edges of the sheets 8 from a sheet-carrying cylinder of the last processing station—here from an impression cylinder 1.1—to the endless conveyor 3, in the present exemplary embodiment according to
The endless conveyor 3 contains a first conveyor carrying first gripper bars 6 for gripping leading gripper edges, and a second conveyor carrying second gripper bars 7 for gripping trailing gripper edges, whose phase angle with respect to the first conveyor can be varied in order to adapt to a respective format of the processed sheets and, for this purpose, is for example constructed by using the teaching disclosed in German Patent DE 12 60 482.
The first and second gripper bars 6 and 7 respectively carried by the lower runs of the endless conveyor 3 constructed as chain conveyors take over the sheets 8 from the transfer drum 5 and transport them in the direction of a stack 9 to be built up in a stacking station 2.3, whose upper side is always kept at a substantially constant level—what is known as the production level—by a lifting mechanism. Of the lifting mechanism, a platform 10 carrying the stack 9 and lifting chains 11 carrying the platform are indicated.
To transfer the sheets 8 to the stack 9, after-grippers 12 following a closed after-gripper path 14 during operation are provided, which take over the processed sheets from the endless conveyor 3, more precisely from the second gripper bars 7, guide them along a transport path determined by the lower runs of the endless conveyor 3 and release them above the stack 9. The after-grippers 12 are disposed on a non-illustrated after-gripper bar, which is guided by a mechanism, not specifically illustrated in
In the event that they are configured as clamping grippers, the after-grippers 12 close under a spring force, in a known manner, and open as a result of rotation of a gripper shaft carrying the after-grippers 12 by a cam follower configuration disposed on the gripper shaft and a gripper opening cam deflecting the latter appropriately. In this case, a respective sheet 8 is taken over at a trailing gripper edge of the same by the after-grippers 12 of one of the second gripper bars 7 guiding the sheet 8 and is transferred to the stack 9.
In an alternative configuration, the after-grippers 12 are constructed as suction grippers and can then advantageously be used in particular when the rotary press is configured exclusively for recto printing operation. The suction grippers then grip the sheets 8 on their unprinted underside and, to this extent, do not need any trailing gripper edge.
The mechanism has in particular a drive wheel 15 which, in the configuration illustrated by way of example here, is driven uniformly via a transmission drive 17 by a motor 16—preferably a geared motor. The motor 16 is disposed on a carrier 18 connected to the gearbox 13. The motor 16 and the transmission drive 17 form a drive 19, which thus, together with a mechanism 24 accommodated in the gearbox 13, forms one structural unit. The gearbox 13 is guided along a stationary rectilinear guide 20 in such a way that the structural unit formed by the mechanism 24 and the drive 19 can be displaced along a horizontal line with respect to the delivery 2.
A mounting 21 likewise fitted in a fixed location bears an actuating motor 22, preferably with a step-down transmission connected downstream, whose output is formed by a threaded spindle 23 which is parallel to the rectilinear guide and which engages with a nut thread permanently disposed on the carrier 18. By appropriate activation of the actuating motor 22, the aforementioned structural unit and therefore, in particular, the mechanism 24 guiding the after-grippers 12 can be set to positions which are correlated with different formats of the processed printing materials.
The drive 19 is configured in such a way that the after-grippers 12 pass through the after-gripper path 14 in the same time as that in which the trailing edge of a following sheet, starting from a specific time, reaches the location assumed by the trailing edge of a preceding sheet at the same time.
The major part of the after-gripper path 14 runs underneath the transport path already mentioned. Only for the purpose of taking over a respective sheet 8 do the after-grippers dip into the transport path. The orientation of the after-grippers 12 in the running direction of the sheets 8 transported by the endless conveyor 3 otherwise remains unchanged during the passage of the after-gripper path 14.
A displacement of the mechanism 24 guiding the after-grippers 12, by the actuating motor 22 and threaded spindle 23, from a first position correlated with the format of a processed sheet 8 into a position correlated with a different format is carried out as required with the motor 16 stopped, that is to say with the machine stopped, or else during the operation of the latter—that is to say with the machine running—for example for the case of position corrections to the gearbox 13. In any case, however, the preset phase angle needed to take over the sheets 8 by the after-grippers 12 from the grippers of a respective second gripper bar 7 and to transfer the sheets 8 to the stack 9, of the mechanism 24 guiding the after-grippers 12 with respect to the printing unit 1 is maintained.
Components corresponding to the components disposed outside the side frame 2.1 (see
The aforementioned fixing of the after-gripper bar 12.1 is carried out to the respective guided mechanism element 24.3. In order to implement the after-gripper mechanism, precautions not illustrated in
In
In a manner analogous to the configuration according to
The step-up ratio between the sprocket shaft 29 and the common drive shaft 30 of the mechanism 24 that guides the after-grippers depends on whether the turn sprocket 3.1 revolves with a single turn or, for example, a half turn. In the case of single-turn revolution, a step-up ratio of 1:1 has to be provided, 1:2 in the case of half-turn revolution.
The configuration reproduced in
The configuration according to
The endless conveyor 3 is constructed as a chain conveyor and contains a first conveyor 31 and a second conveyor 32. A respective one of the conveyors contains a pair of endless chains in the form of roller chains and, during operation, a respective chain of a pair circulates along the inside of a respective one of the side frames 2.1 and 2.2, not illustrated here. The chains of the first conveyor 31 guide the already mentioned first gripper bars 6 for gripping leading gripper edges of the sheets 8, and the chains of the second conveyor 32 guide the likewise already mentioned second gripper bars 7 for gripping the trailing gripper edges of the sheets 8. In order to grip the trailing gripper edges of the sheets 8 by the gripper bars 7, recourse is made, for example, to the teaching disclosed in Published, Non-Prosecuted German Patent Application DE 100 14 417 A1. To this extent, an illustration of the devices required for this purpose is dispensed with at this point. However, it goes without saying that the trailing gripper edges of the sheets 8 can also be gripped by the second gripper bars in another way.
A respective chain of the first conveyor 31 is disposed in the immediate vicinity of a respective side frame 2.1 or 2.2, wraps around a respective first drive sprocket 33 and, in the same way as a respective chain of the second conveyor 32, in particular in regions of direction changes of the chain, runs along chain guides not illustrated here. A respective chain of the second conveyor 32 runs along a chain path which is congruent with the chain path through which the first chains pass and wraps around a respective second drive sprocket 34. The second drive sprockets 34 are disposed between the first drive sprockets 33, in each case in the immediate vicinity of the latter, and their phase angle with respect to the first drive sprockets 33 can be adjusted in a manner explained in more detail later.
The first and second drive sprockets 33 and 34—as explained in more detail later—have a common torque-transmitting connection in production printing operation with a gear wheel of a gear train provided to drive the machine and, in a manner likewise explained in more detail later, are disposed on a sprocket shaft 35, which bears a gear wheel driving the latter and meshing with the aforementioned gear wheel of the gear train and, in the mode of illustration of
The gearbox 13 containing the mechanism 24 for guiding the after-grippers 12 not illustrated in
The drive wheel 15 of the mechanism 24 is incorporated in a flexible drive 36, driven by the endless conveyor 3 during operation, in such a way that a flexible drive run 37 of the flexible drive 36 running parallel to the non-illustrated rectilinear guide 20 for the gearbox 13 (see
As explained in more detail below, in the configuration according to
For this purpose, inter alia, a rotary coupling 40 according to
The construction of the rotary coupling 40, its function and its interaction with an actuating drive to be explained in more detail later can be gathered from
The rotary coupling 40, which can be adjusted from a first into a second operating state and vice versa, is reproduced in the first operating state in
As already indicated at an earlier point and now explained in more detail, the first drive sprockets 33 and the second drive sprockets 34 are disposed on the sprocket shaft 35. The latter is constructed as a hollow shaft. The sprocket shaft 35 is mounted in the side frames 2.1 and 2.2 such that it can rotate, only the side frame 2.2 being reproduced in
The rotary coupling 40 contains an inner coupling ring 44 which is firmly connected to the gear wheel 41—and thus to the sprocket shaft 35 and the first drive sprockets 33—on which tilting levers 46 are supported in radial recesses 45 in the same and, in the first operating state, illustrated in
However, in the first operating state of the rotary coupling 40, illustrated in
As already indicated at an earlier point and previously explained in more detail, during production printing operation of the machine, therefore, the first and second drive sprockets 33 and 34 jointly have a torque-transmitting connection to a gear which is not illustrated here but meshes with the gear wheel 41 and belongs to a gear train provided to drive the machine.
In order to bring about the aforementioned axial displacement of the pressure sleeve 50 in the direction of the disk spring pack 47, a piston-cylinder unit 52 which, for example, can be actuated hydraulically, having a cylinder 53 and a piston 54 is provided. The piston-cylinder unit 52 is connected by a connection 55 to a pressure medium system, not illustrated here, and, in the second operating state, is under the action of a corresponding pressure medium, for example hydraulic fluid.
The cylinder 53 is rotatably mounted on a section of the drive shaft 42 which projects beyond the outer coupling ring 48 and which follows sections of the drive shaft 42 which successively pass through the sprocket shaft 35, the gear wheel 41 and the pressure sleeve 50, and is supported via an axial bearing 52.1 on a shoulder 56 at the end of that section of the drive shaft 42 which projects beyond the outer coupling ring 48.
In the second operating state of the rotary coupling 40, which is illustrated in
The piston 54 is provided with a toothed ring 54.1. Meshing with the latter is a pinion 57.1 of an actuating drive 57, already mentioned at an earlier point and now explained in more detail, which here contains a motor 57.2 which is flange-mounted on a mounting 58 fixed to the side frame 2.2 via studs. The pinion 57.1 is configured to be broad such that, in both operating states of the rotary coupling, that is to say in the extended and non-extended state of the piston 54, it meshes with the toothed ring 54.1.
At an end of the piston 54 facing the outer coupling ring 48, the former bears at least one driver 59 which, in the extended state of the piston 54, produces a form-fitting connection between the piston 54 and the outer coupling ring 48.
The phase angle of the second conveyor 32—represented here by the second drive sprocket 34—can thus be adjusted by the actuating drive 57 for the purpose of rotation with respect to the first conveyor 31—represented here by the first drive sprocket 33—in the second operating state of the rotary coupling 40, to be specific on the basis of the drive connection between the actuating drive 57 and the second conveyor 32 which exists in the second operating state of the rotary coupling 40. When setting the endless conveyor 3 from one format of the processed sheets to another, a corresponding adjustment is carried out and used to set the distance of the second gripper bars 7, guiding the trailing gripper edges of the sheets 8, from the first gripper bars 6 guiding the leading gripper edges of the sheets 8.
After adjustment has been carried out, the rotary coupling 40 is set back into its first operating state, in which the actuating drive 57 is then uncoupled from the second conveyor 32. For this purpose, the connection 55 provided on the cylinder 53 is depressurized, so that, by a return spring 52.2 (see
As
As
In order to set the mechanism 24, in other words the gearboxes 13, to positions correlated with the format of the processed sheets 8, an actuating device that can be actuated rotationally is provided and, for this purpose, is provided with an actuating wheel 13.4. In the present exemplary embodiment, the actuating device is constructed in the form of a spindle drive 66 which can be actuated by the aforementioned transmission drive 65.
According to
Overall, therefore, there are actuating unit in the form of the toothed ring 54.1 of the piston 54, in the form of the transmission drive 65 and in the form of the spindle drive 66 which, in the second operating state of the rotary coupling 40, that is to say when the second conveyor 32 is uncoupled from the first conveyor 31, can be actuated jointly and in a mechanically coupled manner by the actuating drive 57 to the effect that a change in the phase angle of the second conveyor 32 with respect to the first conveyor 31 is carried out in order to adapt the distance of the second gripper bars 7 from the first gripper bars 6 to a different format of the sheets 8, and to adjust the mechanism 24 to a position correlated with this format.
However, these adjustment operations proceed without any change in the phase angle of the mechanism 24 with respect to the printing unit 1. For this purpose, the parameters of the transmission drive 65 (see
In the case of the configuration of the flexible drive 36 according to
As opposed to the configuration according to
In the section of a flexible drive 36′ reproduced in
Again, given a half-turn configuration of the drive sprockets 33 and 34, there is the same diameter ratio between the pitch circle of the drive wheel 39 (see
In an alternative refinement, the torque for driving the flexible drive 36′ according to
In the case of a direct rotationally fixed connection between a deflection sprocket of the second conveyor 32 and the aforementioned drive wheel for the alternative drive of the flexible drive 36′, it goes without saying that this drive wheel has the same diameter as the drive wheel 39, in the same way as that of the second drive sprockets 34 and otherwise—in the configuration present here of the mechanical coupling between the adjustment operations to match the position of the second gripper bars 7 and the after-grippers 12 to the respective format of the processed sheets 8—also the first drive sprocket 33, so that, during a position change to the gearboxes 13, standstill of the drive wheel 15 and therefore the mechanism 24 is again established.
If the sheet-processing machine has a delivery with an endless conveyor that grips the sheets 8 only at their leading edges, then it is equipped with a sheet guide device over which the sheets 8 are drawn. For the case in which the machine is configured for optional operation in the recto and verso printing processes or in the recto printing process, the aforementioned sheet guide device for the first operating mode is preferably configured to produce an air cushion between a respective sheet 8 and a guide surface provided on the sheet guide device. For this purpose, the sheet guide device is connected to a pneumatic system by which sheet-carrying air streams are expelled from air passage openings that are provided in the guide surface.
For the case of the second operating mode, the aforementioned air passage openings communicate with a vacuum generator belonging to the pneumatic system, so that the sheets 8 drawn over the sheet guide devices rest in a defined way on the guide surface.
The sheet guide device can preferably be set to different formats of the sheets 8.
The sheet guide device 67 contains a stationary first guide section 67.1 and a second guide section 67.2 which follows the former in the direction of the stack 9, adjoins the stationary guide section 67.1 and can be set to different formats of the sheets 8, the first guide section 67.1 and the second guide section 67.2 having mutually facing end sections 67.1′ and 67.2′ which interengage in the manner of a comb.
In the position illustrated in
In order to set the second guide section 67.2 to smaller formats, the latter, together with the after-gripper bar 12.1, is displaced in the direction of the stack 9 and, for this purpose, is preferably fixed to the gearboxes 13.
At an end of the second guide section 67.2 facing the stack 9, clearances 69 are formed, in which the after-grippers 12—which can be constructed as clamping or else sucking grippers—engage in order to take over the sheets 8 from the endless conveyor 3.
The end sections 67.1′ and 67.2′ interengaging in the manner of a comb are dimensioned such that, when the second guide section 67.2 is set to the smallest processable format of the sheets 8, the end sections 67.1′ and 67.2′ still intermesh, so that, when processing sheets 8 with a format smaller than the maximum format, a guiding action transversely with respect to the sheet running direction is maintained on the part of the sheet guide device 67, at least in some sections.
Number | Date | Country | Kind |
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102 49 737 | Oct 2002 | DE | national |
Number | Name | Date | Kind |
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3413732 | Koch et al. | Dec 1968 | A |
3861672 | Norton | Jan 1975 | A |
5011125 | Spiegel et al. | Apr 1991 | A |
5431386 | Blaser | Jul 1995 | A |
5988633 | Henn et al. | Nov 1999 | A |
6578846 | Maul et al. | Jun 2003 | B2 |
Number | Date | Country |
---|---|---|
627 851 | Mar 1936 | DE |
1 260 482 | Feb 1968 | DE |
24 58 446 | Jul 1975 | DE |
38 36 254 | May 1990 | DE |
196 28 620 | Jan 1998 | DE |
100 14 417 | Sep 2001 | DE |
446462 | Apr 1936 | GB |
Number | Date | Country | |
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20040113350 A1 | Jun 2004 | US |