A device for clamping a sheet-like roller covering around a roller

Abstract

The device (2) for clamping a roller covering around a roller (10) having a pair of clamping rails (11, 12) comprises a plurality of identical clamping units (4) arranged on a common pivot beam (13), the partial rails (11, 12) of which together form the second clamping rail (12) of the clamping rail pair, the clamping units (4) each having a first lock (50) assigned to the first clamping rail (11) and a second lock (58) assigned to each partial rail (44), the locks (50, 58) selectively holding or releasing the roller covering.

Description

[Technical Field]

[0001] The present invention relates to a device for clamping a sheet-like roller covering around the outer circumferential surface of a rotatable roller according to the preamble of claim 1 . [Background technology]

[0002] EP 0 401 500 A1 discloses a device for adjusting and clamping a flexible printing plate on a plate cylinder of a rotary printing press. In this case, a pair of clamping rails are oriented parallel to the axis of rotation of the plate cylinder. The clamping rails extend over substantially the entire length of the plate cylinder and are pivotally supported on the cylinder body by a lever. This allows for the correction of angular misalignment of the printed image by slightly shifting the position of the printing plate on the plate cylinder.

[0003] In known devices, manual application of roller covers to rollers is tedious. Often, the covers partially slip off the first pair of clamping rails before they can be fully latched onto the second clamping rail and secured by clamping. Wide roller covers, in particular, are difficult to handle and require two people to install.

[0004] A large amount of force is required to press the roller cover into the undersized retaining groove, making removal of the roller cover difficult. Furthermore, the force required significantly increases the risk of damaging the roller, especially when a hammer is used as an aid.

[0005] The concave expansion of the printing plate can be compensated for by a divided clamping rail, as described in DE 10 2010 045 036 A1. For this purpose, the clamping rail is divided into several segments in the axial direction, allowing the clamping force to be applied to each segment individually. Gradual latching of the roller cover onto the partial rails, with each clamping immediately following, facilitates handling during installation, but leads to undesirable uneven expansion of the roller cover. In particular, the sequence of the individual clamping processes influences the expansion and thus the printed image. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] European Patent Application Publication No. 0401500 [Patent Document 2] German Patent Application Publication No. 102010045036 Summary of the Invention [Problem to be solved by the invention]

[0007] It is therefore an object of the present invention to provide an improved device compared to the prior art, which overcomes at least one of the drawbacks of the prior art described. [Means for solving the problem]

[0008] This problem is solved by a device / method having the features of claim 1. Advantageous configurations are evident from the dependent claims.

[0009] For this purpose, a clamping device is provided for clamping the roller cover over the outer periphery of a rotatable roller, where the roller can be a printing cylinder and the roller cover can be a printing plate, and the clamping device has a pair of clamping rails on the outer periphery of the roller, parallel to the rotation axis of the roller, each of which forms an undercut in the form of a notch, into which the leading or trailing edge of the roller cover can be latched.

[0010] The pair of second clamping rails is composed of several identical partial rails in its longitudinal direction. Each of these partial rails is attached to a carriage of one clamping unit. The carriage can move approximately in the circumferential direction with one of the partial rails. In this case, the position of the carriage determines the distance of the partial rail relative to the pair of first clamping rails and thus the clamping force of the roller cover. For this purpose, each clamping unit is equipped with a drive that acts separately on each carriage.

[0011] The clamping device has a lock assigned to the second clamping rail, which is arranged relative to the second clamping rail in such a way that in its closed position, the lock secures the roller cover against accidental slipping out of the holding part of the partial rail when the roller cover is not clamped, and in its open position, the lock releases the roller cover relative to the respective partial rail.

[0012] Preferably, a common switch is assigned to each separate clamping drive, allowing the clamping units to be individually activated. Therefore, for example, when using a narrow roller cover, unnecessary clamping units can be switched off. Furthermore, if necessary, wide roller covers can be stretched or twisted unevenly in an appropriate manner by switching off individual clamping units.

[0013] Preferably, the lock is configured as a lever with a rotation axis so that the leg of the lever can move in a plane oriented approximately tangentially to the roller circumference. It is particularly advantageous if the lock is attached to the carriage of the clamping unit and assigned to a partial rail of this clamping unit. The locking or release of the roller cover is therefore independent of the position of the clamping carriage. This prevents the roller cover from accidentally releasing during premature loosening.

[0014] It is advantageous to arrange the same clamping units on a common pivot beam with a pivot axis arranged approximately radially relative to the roller, so that angular misalignment of the roller covering can be corrected by pivoting this beam.

[0015] The pivoting beam is preferably assigned a feed device with a controllable adjustment drive. In this way, angular misalignment of the roller cover can be automatically corrected without manual intervention. Cam control of the pivoting movement by a cam roller rolling on a cam is particularly advantageous. The cam configuration allows the desired force profile for the pivoting to be set.

[0016] Preferably, the feed device has a push rod which is guided through a hollow shaft in the roller, in this way the drive element, which is particularly sensitive to movement, can be arranged outside the roller and fixed to the frame.

[0017] The invention will now be described by way of example with reference to the drawings, to which reference is made for all details not specifically mentioned in the description. [Brief explanation of the drawings]

[0018] [Figure 1] 1 shows a schematic perspective view of a printing cylinder with a clamping device; [Figure 2] 1 shows a schematic perspective view of a detail of a feed device for pivoting the clamping device; [Figure 3] 1 shows a schematic view of a detail of a feed device for pivoting the clamping device; [Figure 4] 1 shows a schematic view of a clamping unit in different states; [Figure 5] 1 shows a schematic perspective view of a detail of the clamping device. [Figure 6] 1 shows a schematic perspective view of a detail of the clamping device. [Figure 7] 4 shows the lock switching logic of the clamping device. DETAILED DESCRIPTION OF THE INVENTION

[0019] A printing cylinder 1 having a clamping device 2 according to the present invention is shown in Figure 1. A groove 17 penetrates the outer surface 103 of the central cylinder 10. This groove 17 extends in the axial direction y, parallel to the rotation axis 100 of the printing cylinder 1, and accommodates the clamping device 2. The printing cylinder is journalled to the machine frame 5 via shaft attachments 16 located on both sides of the central cylinder 10, as shown in Figure 3.

[0020] The first clamping rail 11 and the second clamping rail 12 cooperate to form a clamping rail pair of the clamping device 2. The clamping rails 11, 12 are axially oriented parallel to one another on the outer peripheral surface 103 of the cylinder 10. In the circumferential direction, the clamping rails 11, 12 have a variable distance 70 from one another. The first clamping rail 11 and the second clamping rail 12 each form an undercut 45 in the form of a groove that opens in the circumferential direction of the cylinder 10. The openings of these two grooves face each other. A printing plate can be hung in the opening by its leading or trailing edge. The narrowing of the distance 70 between the two clamping rails 11, 12 clamps the hung printing plate and thus fixes it to the cylinder 10.

[0021] The clamping rail pair is attached to a beam 13 of the clamping device 2. This beam 13 extends in the axial direction y in a groove 17 of the printing cylinder 1. The beam 13 is mounted so as to be pivotable about an axis 101 extending radially relative to the printing cylinder 1. A slight pivoting 202 of the clamping rails 11, 12 about the radial axis 101 makes it possible to correct the angular position of the printed image. For this purpose, a feed device 3 is provided. For this purpose, the feed device 3 has a controllable positioning drive 34. The positioning drive 34 communicates with the control device 6 via a data line 60.

[0022] The positioning drive 34 acts on the pivotable beam 13 of the clamping device 2 via a transmission that passes axially through the hollow shaft 16 of the printing cylinder 1. To this end, a spindle transmission 35 of the feeder 3 connects the positioning drive 34 to a push rod 36 that extends axially within the hollow shaft 16 of the printing cylinder 1. An arm 37 of the feeder 3, connected to this push rod 36, passes through the end face 104 of the central cylinder 10 and engages in a groove 17 of the printing cylinder 1. The arm 37 is supported in the groove 17 by a linear guide 33. The linear guide 33 is oriented parallel to the rotation axis 100 of the printing cylinder 1 and allows the arm 37 to move linearly in the axial direction 201. A cam roller 31 is attached to the end of the arm 37 that protrudes into the groove 17. The cam roller 31 interacts with a cam 30 of the pivoting beam 13. The beam 13 is supported by a compression spring 32 against the groove 17 so that the beam 13 always abuts against the cam roller 31 of the feed device 3. The linear sliding 201 of the arm 37 causes the cam roller 31 of the arm 37 to roll on the cam 30 of the beam 13, which results in a pivoting movement 202 of the beam 13 about its pivot axis 101.

[0023] The second clamping rail 12 is composed of several partial pieces 44 arranged one after the other in the axial direction y. Each of the partial rails 44 is a component of one of several identical clamping units 4. The structure of one such clamping unit is shown in Figures 4 to 6. The clamping unit 4 consists of a clamping carriage 40. This clamping carriage 40 is held on the pivoting beam 13 of the clamping device 2 by a linear guide 43 and supports one of the partial rails 44. The linear guide 43 is oriented approximately radially with respect to the central cylinder 10 of the printing cylinder 1 and determines the direction of the linear clamping movement 200. For this purpose, the linear guide 43 includes two mutually parallel guide rails.

[0024] The clamping carriage 40 of the clamping unit 4 is operated by a separate drive, which moves the carriage between two end positions. The end position in which the printing plate is clamped is shown in FIG. 4a. A compression spring 41 holds the clamping carriage 40 in this end position and applies a clamping force to the partial rail 44. To release the printing plate, the compression spring 41 is overcome by a hydraulic cylinder 42, so that the clamping carriage 40 occupies another end position, as shown in FIGS. 4b to 4d. Each clamping unit 4 Each clamping unit has a separate switch 38 for driving the clamping carriage 40. In a simple form, this switch 38 can be a manually operated valve (not shown). In this way, the individual clamping units 4 can be switched off or on. 4 For automatic operation of the individual clamping units 4 The pressure lines are combined into a central pressure line as shown in Figure 7. The central pressure line includes a directional control valve that is mechanically controllable as a common switch 39. The common valve and each of the individual valves are arranged in an AND circuit configuration with each other.

[0025] Each tightening unit 4 The clamping device 2 has a first lock 50 assigned to the first clamping rail 11. This first lock 50 is arranged opposite the cutout groove of the first clamping rail 11 for holding the printing plate and is configured to release the holding part for changing the printing plate and to lock it for clamping the printing plate. To this end, this first lock 50 is attached to the pivoting beam 13 of the clamping device 2 and can occupy a closed position 301 shown in Figures 4a to 4c and an open position 300 shown in Figure 4d.

[0026] The first lock 50 is in the form of a lever 53 with two legs 61, 62 arranged at right angles to one another. The first lock 50 is journalled in a rotary bearing 54 of the carriage 40 so as to be pivotable about an axis radial to the printing cylinder. In the closed position 301 of the first lock 50, the first leg 61 of the first lock 50 is aligned parallel to the first clamping rail 11. The small opening width 71 between the first clamping rail 11 and the first lock 50 reliably prevents the inserted printing plate from slipping out. In this case, the second leg 62 faces the second clamping rail 12, and its rear second abutment surface 52 is held by a magnet 55.

[0027] Open position 300 In the closed position 301, the second leg 62 of the first lock 50 is oriented parallel to the first clamping rail. The open width 71 is greater than in the closed position 301, so that the printing plate can be easily latched or removed. In this case, the first leg 61 faces the second clamping rail 12 and is held by the magnet 55 via the first contact surface 51 arranged on its back side. To operate the first lock 50, a grip 57 is provided, which is attached to a lever 53 on a rotary bearing 54.

[0028] The second lock 58 of each clamping unit 4 is arranged opposite the retaining groove of the assigned partial rail on the respective clamping carriage 40. The second lock 58 corresponds in function and structure to the first lock 50 and will therefore not be described further.

[0029] The clamping device 2 comprises a plurality of identical clamping units as described above. 4 a clamping unit 4 are arranged on a common pivot beam 13.

[0030] The individual states of the individual clamping units 4 during plate changing and clamping are shown in Figures 4a to 4d. The printing plate itself is not shown. Figure 4a begins with the clamping state, in which the printing plate is clamped and both locks 50, 58 are held in their closed position 301. When the separate valves are open, the hydraulic cylinder 42 overcomes the clamping spring 41 in the open position of the common directional control valve, moving the carriage 40 to the end position shown in Figure 4b. The spacing 70 between the clamping rails 11, 12 is widened, relaxing the latched printing cylinder. Opening the second lock 58 shown in Figure 4c releases the first edge of the printing plate, allowing it to unwind from the printing cylinder. With the first lock also in its open position 300, as shown in Figure 4d, the printing plate can be completely removed. The process of mounting and clamping the printing plate is reversed. The present application relates to the invention described in the claims, but also includes the following as other aspects. 1. 1. A device for clamping at least one generally sheet-like, flexible roller cover, in particular a printing plate, substantially around the circumferential surface (103) of a roller (10), in particular a printing cylinder, comprising: The roller (10) is supported rotatably about a rotation axis (100) in the axial direction of the roller (10), and at least a first rail (11) disposed on the outer circumferential surface of the roller (10) and substantially parallel to the rotation axis (100) of the roller (10); a second rail (12) formed from at least two partial rails (44) arranged on the outer circumferential surface of the roller (10) and substantially parallel to the rotation axis (100) of the roller (10); The first rail (11) and the second rail (12) each have at least one undercut (45) that holds at least one roller cover in a form-fitting manner; the at least one first rail (11) and the at least one second rail (12) have a variable spacing (70) relative to each other in the circumferential direction of the roller (10); 1. An apparatus comprising two clamping units (4) spaced apart from one another in the direction of the rotation axis (100) of the rollers (10), each clamping unit (4) having at least a carriage (40) movable in the approximate circumferential direction of the rollers (10), a drive (42) drivingly connected to at least one carriage (40), and a partial rail (44) arranged on the carriage (40) and forming a second rail (12), The device is characterized in that at least one lock (58) is arranged opposite at least one of the at least one second rails (12), and the at least one lock (58) has an open position (300) and a closed position (301) alternately with respect to the at least one partial rail (44) assigned to it, and the lock (58) forms a closable holding portion together with the at least one second rail (12) assigned to it. 2. The device according to claim 1, characterized in that at least two clamping units (4) each have a separate switch (38) assigned to at least one drive device (42), each group of at least two clamping units (4) has another common switch (39), and each of the separate switches (38) of the at least two clamping units (4) of a common group is connected to at least one common switch (39) of the same common group in the form of an AND circuit. 3. 3. The device according to claim 1 or 2, characterized in that at least one lock (53) is formed by a lever (53) having two legs (61, 62) and rotatable about an axis (102), the axis of rotation (102) extending approximately radially relative to the roller (10), and the two legs (61, 62) of the lever (53) together form a plane oriented approximately perpendicular to the axis of rotation (102) of the lock (53). 4. 4. The device according to any one of claims 1 to 3, characterized in that at least one of the at least two clamping units (4) has at least one lock (53) assigned to at least one partial rail (44) of the same clamping unit (4). 5. 5. The device according to any one of claims 1 to 4, characterized in that a beam (13) is provided, the beam (13) extending substantially parallel to the rotation axis (100) of the roller (10) and being at least slightly rotatable relative to the roller (10) about a pivot axis (101), and at least two clamping units (4) are arranged on the beam (13), the pivot axis (101) of the beam (13) extending perpendicular to the rotation axis (100) of the roller (10). 6. 6. The device according to claim 5, characterized in that at least one feeder (3) of at least one beam (13) is provided with at least one controllable adjusting drive (34), and the at least one controllable adjusting drive (34) is connected to the control device (6) by at least one data line (60) for exchanging signals. 7. 7. The device according to claim 5 or 6, characterized in that the feeding device (3) comprises at least one cam (30) and at least one cam roller (31) that rolls on the at least one cam (30). 8. 8. The apparatus according to any one of claims 5 to 7, characterized in that at least one push rod (36) of the controllable feed device (3) is provided, the at least one push rod (36) being arranged collinearly with the rotation axis (100) of the roller (10) and extending through the hollow shaft (16) of the roller (10). [Explanation of symbols]

[0031] 1 Printing cylinder 2. Clamping device 3 Feeder, turning 4 Clamping unit 5 Machine Frame 6. Control device 10 Torso 11 First Rail 12 The Second Rail 13 Beam 15 Rotary bearing 16 hollow shaft 17 Groove 20 Cover 30 Cam 31 Cam Roller 32 Compression spring 33 Linear guide 34 Positioning drive unit 35 Spindle transmission device 36 Push rod 37 Arm 38 Switch 39 Group Switch 40 Fastening carriage 41 Compression spring 42 Hydraulic cylinder 43 Linear guide 44 Fastening device 45 Undercut 50 First Lock 51 first contact surface 52 Second contact surface 53 Lever 54 Rotary bearing 55 Magnet 56 Holder 57 Grip 58 Second Lock 60 data lines 61 First Leg 62 Second Leg 70 intervals 71 Open width 100 Rotation axis 101 Swivel axis 102 Rotation axis 103 Outer surface 104 End face 200 Linear tightening motion 201 Linear Feed Motion 202 Circular Movement 203 First Rotational Motion 204 Second Rotational Motion 300 open placement 301 Closed Configuration

Claims

1. 1. A device for clamping at least one generally sheet-like, flexible roller cover, in particular a printing plate, substantially around the circumferential surface (103) of a roller (10), in particular a printing cylinder, comprising: The roller (10) is supported rotatably about a rotation axis (100) in the axial direction of the roller (10), and at least a first rail (11) disposed on the outer circumferential surface of the roller (10) and substantially parallel to the rotation axis (100) of the roller (10); a second rail (12) formed from at least two partial rails (44) arranged on the outer circumferential surface of the roller (10) and generally parallel to the rotation axis (100) of the roller (10); The first rail (11) and the second rail (12) each have at least one undercut (45) for retaining at least one roller cover in a form-fitting manner; the at least one first rail (11) and the at least one second rail (12) have a variable spacing (70) relative to each other in the circumferential direction of the roller (10); 1. A device comprising at least two clamping units (4) spaced apart from one another in the direction of the rotation axis (100) of the roller (10), each clamping unit (4) having at least a carriage (40) movable in the substantially circumferential direction of the roller (10), a drive (42) drivingly connected to at least one carriage (40), and a partial rail (44) arranged on the carriage (40) and forming a second rail (12), At least one lock (58) is arranged opposite at least one partial rail (44) of at least one second rail (12), and the at least one lock (58) has an open position (300) and a closed position (301) alternately with respect to the at least one partial rail (44) assigned to it, and the lock (58) forms a closable holding part together with the at least one partial rail (44) assigned to it; 1. A device characterized in that at least one lock (58) is formed by a lever (53) having two legs (61, 62) rotatable about a rotation axis extending approximately radially relative to the roller (10), the two legs (61, 62) of the lever (53) together forming a plane oriented approximately perpendicular to the rotation axis of the lock (58).

2. 2. The device according to claim 1, characterized in that the at least two clamping units (4) each have a separate switch (38) assigned to at least one drive (42), each one group of at least two clamping units (4) has another common switch (39), and each of the separate switches (38) of the at least two clamping units (4) of a common group is connected in the form of an AND circuit to at least one common switch (39) of the same common group.

3. 3. The device according to claim 1, wherein at least one of the at least two clamping units (4) has at least one lock (58) assigned to at least one partial rail (44) of the same clamping unit (4).

4. 4. The device according to claim 1, further comprising a beam (13) extending substantially parallel to the rotation axis (100) of the roller (10) and at least slightly rotatable relative to the roller (10) about a pivot axis (101), on which at least two clamping units (4) are arranged, the pivot axis (101) of the beam (13) extending perpendicular to the rotation axis (100) of the roller (10).

5. 5. The device according to claim 4, characterized in that at least one feed device (3) of at least one beam (13) is provided with at least one controllable adjusting drive (34), the at least one controllable adjusting drive (34) being connected to the control device (6) by at least one data line (60) for exchanging signals.

6. 6. The device according to claim 4 or 5, characterized in that the feed device (3) comprises at least one cam (30) and at least one cam roller (31) rolling on the at least one cam (30).

7. 7. The device according to claim 4, wherein at least one push rod (36) of the controllable feed device (3) is provided, the at least one push rod (36) being arranged colinearly with the rotation axis (100) of the roller (10) and extending through the hollow shaft (16) of the roller (10).

Images