EP3397492A2

EP3397492A2 - Pressure plate clamping rail

Info

Publication number: EP3397492A2
Application number: EP16819550.1A
Authority: EP
Inventors: Hans-Georg Eitel; Michael Rother
Original assignee: Manroland Sheetfed GmbH
Current assignee: Manroland Sheetfed GmbH
Priority date: 2015-12-31
Filing date: 2016-12-21
Publication date: 2018-11-07
Anticipated expiration: 2036-12-21
Also published as: EP3397492B1; DE102016125012A1; CN108430778B; WO2017114719A3; WO2017114719A2; CN108430778A

Abstract

The invention relates to a device for clamping flexible pressure plates by means of lifting elements (39, 40) which are in the form of a knee lifting drive and arranged in a manner parallel to an axis on a lower rail (43). In order to improve the clamping effect, the lower rail (43) is mounted so that it can be moved linearly and radially with respect to the plate cylinder (1) and with respect to an upper rail (44). One or more spring elements (47) acting upon the lifting elements (39, 40) are provided for moving the lower rail into a clamping position by displacing the lifting element (39, 40) into a working position. One or more expandable pneumatic or hydraulic elements (50) for moving the lower rail (43) into an open position by moving the lifting elements (39, 40) from the working position are provided.

Description

The invention relates to a device for clamping flexible printing plates on the plate cylinder of a rotary printing press according to the preamble of patent claim 1.

By DE-OS 26 26 503 a printing plate clamping device has become known, in which a pressure plate end is clamped between parallel clamping surfaces of a housing-fixed plate support and a perpendicular thereto guided terminal block. A movement of the terminal block via a plurality of axially parallel toggle mechanisms on which, in each case in the region of the toggle joint, an eccentric acts. The eccentrics are arranged on a common shaft and are operated together when rotating the shaft. The movement of the toggle mechanisms takes place via a stretched position into a stable upper dead center position against a respective stop formed as a second eccentric. To move the toggle joints out of their stable top dead center position, the second eccentrics are pivoted by means of a second common shaft against the direction of action of the first eccentric.

A disadvantage of the devices shown in DE-OS 26 26 503 are that the pressure plate clamping device must be operated by hand or with tools, which leads to the extension of set-up times. In addition, an automatic operation is not possible.

From DE 37 31 039 A1 a device for clamping flexible printing plates on the plate cylinder of a rotary printing machine is known. In this device, a plurality of toggle linkage are arranged axially parallel to operate a terminal block. The toggle linkage is made by means of several springs in an extended position and brought by means of a pneumatically actuated device from this extended position.

Furthermore, plate clamping rails and Lackformträgerspannschienen in sheetfed offset presses for the automated clamping and clamping of printing plates or paint mold carriers from DE 10 2007 002 785 B4 and DE 20 2007 002 299 U1 are known, which work with at least one hose segment on each side of a Clamping movement of the slide rails generating toggle lever drive are arranged.

The invention has for its object to provide a clamping device for flexible printing plates on the plate cylinder of a rotary printing machine, which makes it possible that an operation of the clamping device can be done without tools.

The object is achieved by the characterizing part of claim 1.

The achievable with the invention advantages are in particular that can be dispensed with tools when retooling the printing press. Consequently, no intervention points for the tools need to be provided on the plate cylinder. In particular, it is possible by the device according to the invention to provide a remote or foot control, so that an operator when retooling the machine has his hands free.

The pressure hose no longer presses directly on the knee lever to open the rail. The force of the pressure hose is guided centrally via pressure pieces on the spring. The pressure pieces run through the lever segments, which are thus simultaneously axially guided in their position. Thus, the force of the pressure hose is given to the compression spring without loss of leverage. This allows an efficient design. The device is suitable for clamping different thicknesses / thicknesses. In the following, only printing plates are mentioned. The clamping force changes only slightly depending on the material thickness to be clamped. A setting behavior or wear of the components for generating the clamping force is automatically compensated and only leads to negligible clamping force changes, in particular, only to slight increases in the clamping force.

Due to the concept, the components involved in the clamping process can be executed mainly with standard tolerance values. The clamping force can be adjusted individually depending on the design interpretation in the simplest way.

If no pressure plate is clamped in the plate clamping rail, the system can nevertheless close completely depending on the design, so that the clamping rail can remain in the printing machine even without a clamped plate, since the mechanism is biased and nothing can move uncontrollably when moving. Alternatively, a stop for fixing the rail elements can be provided for the basic position.

The closing process generates no noise. The toggle lever drive does not deflect, so that no direction of force reversal can occur within the movable bottom rail. It must also be compensated no loss of clamping, because the toggle lever drive shortens again after passing through the top dead center and thereby takes away clamping force.

Force changes are slowly building up and down. This protects the design. A knee lever moves the lower rail. Depending on the position of the toggle lever, the plate tension rail is closed (the plate is clamped) or the plate tension rail is open.

The positions of the toggle lever are achieved as follows:

- A spring presses laterally, against the toggle joint (this assumes a convex position to the spring), thereby the knee lever end points, which on one side of the housing and on the other side at the Be movable lower rail are fastened, pressed apart. The rail is closed and the plate is clamped.

To open the plate clamping rail, e.g. pressurized a pressure hose with compressed air. The pressure hose is positioned concavely to the knee lever on the opposite side to the spring. The pressure hose works against the spring force, the

Toggle ends shorten and the bottom rail moves down. An integrated stop limits the opening stroke. Instead of a pressure hose, another power source can be used.

- If the pressure hose is vented, the pending spring force generates a surplus of force again and the plate tension rail closes.

The toggle never kills. The clamping force results from the force triangle, which exerts the spring by means of the angular position of the toggle lever on the lower rail in the closing direction.

As the material of the pressure plate to be clamped becomes stronger, the force triangle deteriorates in the sense that the less resultant force for closing the plate tension rail is generated, but the spring force increases because the spring is more biased in this position. In the usual plate thickness clamping range of 0.2 to 0.4 mm and in the case of paint carrier thicknesses of up to approx. 2 mm (in the case of paint carriers), almost identical resulting clamping forces result depending on the geometric design.

By adjusting the spring position to the knee lever, the clamping force can be adjusted. Change e.g. Clamping lever lengths or positions of Klemmhebel- end points due to wear or exploitation of manufacturing tolerances of the components involved, the resulting behavior ultimately results as in the power structure for clamping different material thicknesses. The influence on the clamping force is low or at most leads to a Klemmkrafterhöhung, since the toggle is further stretched by wear.

Depending on the design, a theoretical overpressing of the lower rail into the upper rail can take place, so that the system also jams, if no record is found. Toggle levers, springs and bottom rail can be divided into different segments via the format width. As a result, manufacturing tolerances of the components can be better compensated. A uniform clamping force over the entire clamping range is achieved.

By means of improvement measures, an influence by lateral forces is avoided, which arise in the prior art according to FIG. 1 and when using a pressure hose in the case of direct contact with the toggle levers. Transverse forces pull the two toggle segments apart in their common pivot point. Manufacturing tolerances are pressed into their final position, which reduce the opening gap, but negatively affect the accuracy and reproducibility of the clamping operation before a subsequent clamping operation.

In the solution according to the invention but now no lateral forces occur more. Therefore, the lower clamping rail can be easily and with little force e.g. Press downwards in the direction of the "rail opening" function by means of a pull or compression spring, a lever, etc. Thus, the toggle lever package always remains under sufficient play-avoiding pressure and is virtually constantly internally in a backlash-free connection but free in the plate clamping rail and no connecting elements to the lower clamping rail, to the housing or between the toggle lever segments are necessary among each other.

Therefore, the clamping system is inexpensive and easy to install.

The pressure piece is made in two parts. A second smaller pressure piece is designed axially displaceable in the first pressure piece. Thus, individual springs on the thread in the first pressure piece by means of a screw, supported on the rail body, pressed (assembly / disassembly / repair) without the pressure hose is inflated.

The second smaller axially displaceable pressure piece remains in its position and thus does not cause any opening of the rail. If at least two pressure pieces are passed through a toggle package this axial displacement necessary, otherwise the system will be damaged. If this axial displaceability were not given, the second spring would work against the first spring via the toggle joint package and would lead to tension forces and damage within the rail.

Execution technology includes a toggle package three springs. Several toggle assemblies are inserted within a plate tension rail.

In addition to a solution of the prior art, two exemplary embodiments of the invention are illustrated below with reference to drawings and explained in more detail in a description. It shows

1 shows a section through a known plate fastening device, FIG. 2 shows an embodiment of a plate fastening device,

FIGS. 2a / 2b show two force diagrams for a plate fastening device;

FIG. 3 shows a detail of a plate fastening device,

FIG. 4 shows a partial view of the clamping effect of toggle lever rails of the plate fastening device,

5 shows a detailed view of the plate fastening device and FIG. 6 shows a partial view of the plate fastening device in partial section.

Figure 1 shows a device according to the prior art. A plate cylinder 1 is provided with a cylinder channel 2 for receiving two plate clamping rails 3, only one of which is shown here. A plate clamping rail 3 is provided on the bottom 5 with a rail body 4 extending over the length of the plate cylinder 1. The rail body 4 is displaceable in the cylinder channel 2 in the direction of a left and a right side boundary 6, 7. In the axis-parallel direction a plurality of bearing points 8 for pivotally receiving the respective lower end 1 1 are arranged by lower rail couplings 9 a toggle lever drive, the upper end 12 are pivotally connected to a then lower end 13 of upper rail nenkopeln 10, wherein upper ends 14 of the upper Rail coupling 10 are pivotally mounted in bearing points 15. Camps- Points 15 are arranged on a clampable for clamping the pressure plates relative to the rail body 4 upper rail 16. This has a T-shape and is arranged with a trained as a bearing 17 rounded foot in one of the left side boundary 6 associated recess 18 of the rail body 4. The left end of the upper rail 16 forms the terminal block 19 and works against a plate support 20 at the top of the rail body 4, so that there the end of a pressure plate 21 is clamped. On an upper side on the right side boundary 7 of the rail body 4, a guide rail 22 is fixed, which supports the upper rail 16 in the clamping movement.

Under the guide rail 22 is formed between a wall of the rail body 4, the coupling 9 and 10 over the cylinder length reaching pressure chamber 23 in which one or more inflatable elastic tubes 24 are added. In the left-hand side boundary 6 of the rail body 4, a compression spring 26 acting on each toggle lever drive 9, 10 is arranged in a respective recess 25. The compression springs 26 are based on the bottom of the recesses 25 and press the toggle lever drive 9, 10 at least in an extended position. The hoses 24 are arranged counteracting the compression springs 26 and deflect the toggle linkage 9, 10 from the extended position to open the upper rail 16 to solve the Plattenklemmung against the Plattenläläge 20.

On the left wall of the cylinder channel 2 a plurality of recesses 27 are provided in the rail body 4, in each of which an inflatable, elastic bellows 28 is mounted and is supported on the channel wall. On the opposite channel wall a plurality of compression springs 29 are each arranged in a respective recess 30 of the rail body 4 for displacement of the rail body 4. These

Compression springs 29 act horizontally between the rail body 4 and the channel side wall against the force of the bellows 28 for displacement of the rail body 4 approximately to a circumferential direction to the plate cylinder 1 in the cylinder channel 2. In Figure 2, the inventive basic shape of a novel plate clamping device 3 is shown, the one Includes pressure plate clamp and for those in the The following general requirements for proper pressure plate clamping apply in more detail.

A plate tension rail containing a pressure plate clamping device must be suitable for clamping pressure plates or paint mold carriers with different plate thicknesses. In the following, only printing plates are mentioned for this purpose. The clamping force should change as little as possible depending on the material thickness to be clamped. It should be noted, however, that mainly low-compression materials such as aluminum plates, plastic clichés or high-strength rubber or printing blankets should be provided for clamping in such pressure plate clamping rails.

A setting behavior or wear of the components for generating the clamping force should be compensated automatically and may only lead to negligible, the clamping effect does not worsen clamping force changes.

Due to the inventive concept, the components involved in the clamping process can be carried out mainly with standard tolerance values.

If required, the clamping force itself or its basic setting can be made individually adjustable in a simple way by appropriate design interpretation.

The functional sequence of the clamping process itself is controlled in a conventional manner via one or more pneumatic valves. If no pressure plate is clamped, the system nevertheless closes completely, depending on the design of the toggle lever drive contained here, so that the plate clamping rail can remain in the printing machine even without a clamped pressure plate. The mechanism is so biased and can not move uncontrollably when moving the plate cylinder.

In a simple way, ensuring the prestressing of the non-tensioned system can also be achieved by an intrinsic stop. consequences. Such a stop directly to the toggle elements or with the interposition of the pressure hose or

The closing process generates no noise. The used toggle lever drive is designed so that it does not overturn over its dead center with clamped pressure plate, so that there can be no direction of force reversal with an unwanted reduction in clamping force on the movable bottom rail.

Furthermore, in comparison to systems which overshoot the dead center of the toggle lever drive in an end position at a stop, no clamping force loss must be compensated. This is necessary because the effective length of the toggle lever drive again shortens after passing through the top dead center and thereby the clamping force is reduced. Furthermore, force changes slowly build up and down and protect the moving parts and bearings of the device. In Figure 2 it is shown that for Druckplattenklemmung a toggle lever drive with a lower arm 39 and an upper arm 40 is used, which are connected by a toggle joint 42 together. The toggle lever (elements 39, 40, 42) is supported in a rail body 41 and disposed between a lower rail 43 and the rail body 41 vertically movable for the purpose of pressure plate clamping. The toggle joint 42 connects the lower and upper links 39, 40. The upper link 40 is supported upwardly against the vertically movable lower rail 43, which by the pivotal movement of the toggle lever (elements 39, 40, 42) linearly towards an upper rail 44 is moved. The upper rail 44 is a fixed or rigidly mounted part on the rail body 41. Depending on in what current position (stretched or kinked) the toggle lever (elements 39, 40, 42) is the clamping function of the plate clamping rail 3 is closed and a pressure plate 45 is clamped between the lower rail 43 and the upper rail 44 or the clamping function of the plate clamping rail 3 of upper 44 and lower rail 43 is open. Furthermore, a sleeve-shaped pressure piece 46 is longitudinally movably arranged in the rail body 41, which is loaded by a compression spring 47 and is associated with one of the compression spring 47 opposite effective surface of the toggle joint 42. The compression spring 47 is supported on the rail body 41 in an annular groove 47a serving as spring guide.

If, with the inclusion of the annular groove 47a of the respectively serving to guide a compression spring 47 bottom portions 48 as a. 41 adjustable insert element is formed by a thread in the rail body, each of these elements thus formed in the region of an annular groove 47a for presetting or adjustment of the spring force of each acting there compression spring 47 relative to the toggle lever 39, 40, 42 are used.

The rail body 41 is closed by means of a cover 51, which thus forms a pressure chamber 49 with respect to the toggle lever drive 39, 40, 42. Further, rail body 41 and cover 51 in the upper space a parallel guide for the vertical movement of the lower rail 43rd

In the pressure chamber 49, a pressure hose 50 is arranged, which is coupled to at least one pneumatic line via a valve control. By means of the valve control, the pressure hose 50 can be supplied with compressed air, so that the pressure hose 50 is inflated and under the support on the cover 51 exerts a force against the toggle lever drive 39, 40, 42. The force applied by the pressure hose 51 acts on the toggle lever drive against the force of the spring 47th

The positions of the toggle lever are achieved as follows:

- The longitudinally movably arranged in the rail body 41, sleeve-shaped pressure member 46 is loaded by the compression spring 47 which is supported in the annular groove 47a on the rail body 41 and arranged in the region of the toggle joint 42 against the upper 40 and the lower arm 39 (convex home position for Compression spring 47) presses. The upper and lower toggle end points 39a, 40a, which on the lower side on the rail body 41 in

Cylinder channel 2 of the plate cylinder 1 and on the upper side at the movable chen lower rail 43 are pivotally mounted or articulated, are pressed apart. The nip of the plate clamping rail 3 is closed by moving the lower rail 43 upwards relative to the rail body 41, so that the pressure plate 45 is clamped between the movable lower rail 43 and the fixed upper rail 44. The clamping surfaces on the upper rail 44 and the lower rail 43 are roughened or structured for improved power transmission.

To open the plate clamping rail 3, e.g. a pressure hose 50 is supplied with compressed air. The pressure hose 50 is positioned on the concave side of the toggle lever drive 39, 40, 42 on the opposite side to the pressure piece 46 loaded by the compression spring 47. The pressure hose 50 operates when pressurized against the spring force of the compression spring 47, so that the toggle lever ends 39a, 40a their distance shortening to move toward each other and the lower rail 43 moves relative to the rail body 41 linearly downwards and away from the upper rail 44th means an integrated stop that can act on the handlebars 39, 40 or the pressure piece 46, the opening travel of the toggle lever drive 39, 40, 42 limit. Instead of a pressure hose 50, another flexible power source in the manner of a pneumatic muscle can be used.

- If the pressure hose 50 is vented again, the spring force from the compression spring 47, the toggle lever drive 39, 40, 42 stretch again and the clamping function of the plate clamping rail 3 closes again. Here, the toggle lever 39, 40, 42 never moves over its dead center and thus does not respond to a release position. This can be realized by a stop.

The clamping force of the plate clamping rail 3 can be derived from a force triangle, which results from the force K _F and direction of force of the compression spring 47, the length and the angular position of the elements of the toggle lever 39, 40, 42 and the thickness of each thrilling pressure plate 45. Thus, a vertical force component is exerted as a clamping force K _K on the lower rail 43 in its closing direction against the upper rail 44. This effect is shown schematically in FIGS. 2a and 2b. Thus, from a horizontally acting on a lower end of a link 40 spring force F _{F is} a vertically acting at an upper end of the arm 40 clamping force F _K , which corresponds to the inclination of the upper arm 40 due to the thickness of the pressure plate 45 to be clamped to the lower rail 43 trains.

If, according to FIG. 2b, the material of the pressure plate to be clamped becomes thicker, the effect of this force triangle of K _F and K _{K is} worsened in the sense that a lower resultant force is generated for closing the clamping gap of the plate clamping rail 3 or for clamping a pressure plate , At the same time, however, there is a greater effective spring force, since the compression spring 47 is also more strongly biased in this more strongly deflected position.

Plate thicknesses of 0.2 to 0.4 mm are usually used for offset printing plates and up to approx. 2 mm for paint mold carriers. This results in a function of the geometric design, a nearly identical resulting clamping force. The two following practical examples are arbitrarily chosen to show that considerably differences in thickness provoke comparatively small clamping force differences in the plate clamping rail:

- Panel thickness 1, 9 mm clamping force 1 .151 N

- Plate thickness 0.27 mm clamping force 1 .310 N

If, for example, clamping lever lengths or the length of the links or positions of clamping lever end points change in the illustrated arrangement due to wear or utilization of manufacturing tolerances of the components involved, this has no effect on the clamping action of the plate clamping rail 3, since such dimensional changes act as the clamping of printing plates with different material thicknesses. The influence on the clamping force is low and causes by a slight extension of the toggle lever system rather an increase in force and thus in any case no deterioration in function. Depending on the design of the lever lengths of the handlebars 39, 40 can theoretically be carried over its dead center position during the installation of the lower rail 39 relative to the upper rail 40, if no pressure plate 45 is provided in the nip. Thus, the system jams the plate clamping rail 3 and is automatically in a secure state even without use for a printing process.

The toggle lever drive 39, 40, 42 and the compression springs 47 may be arranged several times next to each other over the format width or the length of the plate cylinder 2. This also applies in particular if the lower rail 43 or the entire rail body 41 is divided into a plurality of possibly different lengths of segments in order to achieve a further adjustability. In this case, each of the segments can be assigned independently toggle lever drives 39, 40, 42 and compression springs 47. In this way, manufacturing tolerances between the different components can be better compensated. This achieves the most uniform possible clamping force over the entire clamping area.

The arrangement and dimensioning of the compression springs 47 is designed such that the clamping force applied to the lower rail 43 always corresponds to at least one minimum clamping force, by means of which secure clamping of the pressure plate 45 in the clamping gap between upper 44 and lower rail 43 is ensured.

FIG. 3 shows a further development of the embodiment according to FIG. 2, the orientation of the plate clamping rail 3 being rotated by 180 degrees in the illustration. The toggle lever drive with lower arm 39 and upper arm 40 is connected to a not visible here toggle joint 42 (see Fig. 4) and is supported between the rail body 41 and the vertically movable lower rail 43 from. The upper arm 40 is supported upwardly with an upper end 40 a in a bearing 43 a on the underside of the lower rail 43 from. The lower link 39 is supported at the bottom with a lower end 39 a in a bearing 41 a in the interior of the rail body 41 from. Furthermore, in a guide opening 41 b in the rail body 41 longitudinally movable a sleeve-shaped first pressure piece 52 is arranged, which sits on an annular collar 52 a on a compression spring 47 and inside a cylindrical sleeve opening 52 c has.

The first pressure piece 52 is formed on its cylindrical outer side with a sufficiently large clearance relative to the guide opening 41 b, so that it can not come to tilting or increased friction during longitudinal movement of the pressure member 52 within the guide opening 41 a.

The pressure piece 52 is under a coaxial force effect which is applied by the pressure spring 47 on the annular collar 52a. At the pressure spring 47 opposite side of the annular collar 52a is formed on the pressure piece 52 an active surface, from which the force of the compression spring 47 is centrally introduced to the toggle joint 42.

The compression spring 47 is supported on its lower side in an annular groove 47a on the rail body 41 which is concentric with the guide opening 41b and serves to guide the compression spring 47b.

Again, if necessary for the purpose of Federachstellung as adjustable to be executed bottom portion 48 is located on the rail body 41. The first pressure piece 52 is further provided in extension of the guide opening 41 b with a hollow cylindrical extension 52 b. The extension 52b extends through the region of the toggle joint 42 in the region of an opening 55. The opening 55 is formed by corresponding, approximately semicircular recesses in the mutually facing sides of the links 39, 40.

The plungers 52 thus project with the cylindrical extension 52b through the links 39, 40 which serve as lever segments of the toggle lever drive, so that at the same time the links 39, 40 are guided and secured parallel to the plate cylinder axis in the respective working position. The first pressure piece 52 is associated with a further, mushroom-shaped pressure piece 53, which is provided with a bolt-shaped projection 53b in the interior of the guide Opening 52c is slidably disposed in the first pressure piece 52 and at the opposite end has an effective surface 53a, which has a larger diameter than the opening 55 between the links 39 and 40. The second pressure piece 53 and the toggle lever 39, 4, 42 opposite is again Pressure hose 50 disposed in a closed by a cover 51 pressure chamber 49 within the rail body 41.

The rail body 41 also forms here with the cover 51 in the upper region a parallel guide for the vertical movement of the lower rail 43rd

The pressure hose 50 is again coupled to at least one pneumatic line via a valve control, via which the pressure hose 50 is supplied with compressed air and inflated, so that it is supported on the cover 51 via the second pressure piece 53 a force against the toggle lever drive 39, 40, 42 exciting compression spring 47 exerts. The force applied by the pressure hose 51 acts on the second pressure piece 53 on the first pressure piece 52 and thus against the force of the spring 47th

To limit the distance of the toggle lever drive in the direction of the pressure chamber 49, the lid 51 is provided with a stop surface 51 a, which extends over the bottom of the lid 51 in the region of the toggle joint 42.

Alternatively, such stops can also be integrated on the pressure pieces 53, for example in the area of the effective surface 53a, that they bear against the rear wall of the lid 51 (see FIG. 5).

For introducing force during pneumatic inflation of the pressure hose 50 on the active surface 53a of the second pressure piece 53, a force-guiding element 56 in the form of a sheet is provided. The force-conducting element 56 may be fastened to the pressure hose 50 and extends over a plurality of pairs of the first 52 and second pressure pieces 53 arranged on a common toggle lever drive. The assignment of such force-conducting elements 56 to respective toggle lever drives 39, 40, 42 is shown in FIG. Here is per toggle lever drive a force 56th over all openings 55 and thus also over the there arranged in the assembled state pressure pieces 52, 53 shown.

Figure 4 shows basically two toggle mechanisms 39, 40, 42, wherein the arrangement of the openings 55 in the transition of the links 39, 40 is shown on both sides to the toggle joint 42. The links 39, 40 are each arranged as a paired packet between the rail body 41 and the lower rail 43: Each toggle lever drive each has three openings 55, which in each case a pair of pressure pieces 52, 53 is assigned.

In Figure 3 and Figure 4, a tension spring 54 is also shown in each case, which engages the lower rail 43 and is secured to the rail body 41. One or two such tension springs 54 are each associated with a toggle lever drive, but can also be assigned as needed to a plurality of toggle drives and serve to maintain contact between the loosely interacting individual elements of the toggle lever lower rail 43, upper arm 40 and lower arm 39 at the joints or hinge points 41st a, 42 and 43a.

Of course, instead of the illustrated tension springs 54, for the above-mentioned purpose, it is also possible, for example, in a suitably constructively adapted arrangement. Compression springs or other non-positive holding devices are used.

In Figure 5 and Figure 6 functional details of a toggle lever drive are shown, which again emphasize the simplicity of the construction of the plate clamping rail. FIG. 5 shows the function of assembling the toggle lever drive. Compared to FIG. 3, here each force-conducting element 56 is connected to a pressure piece 53 by means of a holding element 57 of a latching connection which is arranged on the active surface 53a of the second pressure piece 53. Thus, all of a toggle drive associated with a second pressure pieces 53 can be hooked by means of the holding elements 57 and easily associated with the first pressure pieces 52 in the openings 55 of a toggle lever drive on a force. For this purpose, the (according to the embodiment) three plungers 52 of a toggle lever 39, 40, 42 associated with the corresponding openings 55 (see Figure 4) on compression springs 47 on the rail body 41 corresponding to the respective annular grooves 47a used.

Furthermore, each retaining element 57 can serve as a stop for limiting the opening movement of the toggle lever drive in the direction of the cover 51. In this case, each pressure piece 53 then abuts, via a respective holding element 57, against the vented pressure hose 50 present on the cover 51, and the toggle lever drive is in a play-free secured and opened state with the assistance of the tension spring 54. In this case, no separate stop surface 51 a is provided on the lid 51, since it is now formed by the lid 51 itself.

For mounting the clamping mechanism of the plate clamping rail:

In order to use the respective upper 40 and lower arms 39 together with the respective lower rail 43 in the rail body 41, the compression springs 47 must be biased, otherwise the toggle lever drive would come in an extended position and could not be inserted. Therefore, each first pressure piece 52 is clamped by means of a retaining screw 58, which is screwed into a thread in the interior of the guide opening 52c, against the respective pressure spring 47 resting against the rail body 41. The retaining screw 58 can be tightened against the stop on the rail body 41 against a shoulder on the cylindrical collar 52 a of the first pressure piece 52, so that the pressure piece 52 reaches its lowest possible position in the rail body 41. This given under bias of the retaining screw 58 mounting starting position of a toggle lever drive is shown in Figure 5 in solid lines. Thus, the upper 40 and lower arm 39 can be easily inserted into the bearings 41 a, 43 a on the rail body 41 and also inserted lower rail 43 by joining their toggle joint 42.

Finally, for this assembly process, the lower rail 43 is still secured by means of the tension spring 54, wherein the tension spring 54 in Figure 5 for clarity because not shown. By the spring force of the tension spring 54, the lower rail 43 is pulled by its bearing 43 a against the upper arm 40, so that the upper arm 40 hired by the toggle joint 42 against the lower arm 39 and the lower arm 39 in the bearing 41 a the rail body 41 is provided without play.

Thereafter, the second pressure pieces 53 are inserted into the guide holes 52 c of the first pressure pieces 52. In a preferred embodiment, this process can take place together with the force-conducting elements 56 latched to the holding elements 57, to which the pressure hose 50 belonging to the unit is then inserted.

Alternatively, the plungers 53 are used individually when the force-transmitting elements 56 are loosely inserted or shared with a respective pressure hose 50, e.g. be connected by gluing, installed.

Finally, at the end of the assembly process, the lid 51 is fixed on the rail body 41 for closing the plate clamping rail 3. In this case, the guide of the lower rail 43 is ensured with little play between the corresponding guide surfaces on the rail body 41 and on the cover 51.

In each case an air supply connected to each of the pressure hoses 50 inserted inside the plate clamping rail 3 is required for operating the plate clamping rail by means of compressed air. These air supply lines are led out of the plate clamping rail 3 by openings, not shown in the figures, in the cover 51. Only then can the retaining screws 58 with washers 59 are removed from the composite of the plate clamping rail. The after removal of the retaining screws 58 adjusting mounting position is shown in dashed lines, in which case the toggle lever under load by the compression spring 47 on the or the pressing pieces 52 in a nearly extended clamping position between the rail body 41 and the upper rail 44 adjacent lower rail 43 is located. In the sequential removal of the retaining screws 58, a pressure piece 52 is then employed after the other by its compression spring 47 against the toggle lever drive. The toggle lever drive is then supported via the second pressure piece 53 on the cover 51. The buildup of force from the various compression springs 47 takes place successively and without excess force, since the toggle mechanisms can move independently of the pressure pieces 52, 53.

The end position of the toggle lever drive is drawn by dashed lines, wherein the pressure piece 53 is supported with the holding element 56 of the latching device on the pressure hose 50 which bears against the inner wall of the lid 51.

Finally, FIG. 6 also shows functional details of a toggle lever drive with regard to the embodiments of the bearings of the links 39, 40 and the toggle joint 42. Here, the cylindrical extension 52a of the first pressure piece 52 has been omitted for clarity.

The lower arm 39, the upper arm 40 and the lower rail 43 are relative to each other and with the rail body 41 by loose bearings 41 a, 42, 43 a (sliding bearings) coupled. The joint function of these bearings 41 a, 42, 43 a is ensured by the holding force of the tension spring 56. For this purpose, the tension spring 56 is fastened under a predefined tension between the lower rail 43 and the rail body 41, wherein the force flow resulting from the tension includes the toggle lever drive. Thus, the components lower link 39, upper link 40 and lower rail 43 with each other and the rail body 41 in the bearings 41 a, 42, 43 a coupled together without play.

Frequent switching movements during the opening and closing of the plate clamping rail for clamping printing plates result in setting effects in the bearing points 41 a, 42, 43 a and minimal wear on the bearing surfaces during operation of the printing press. This effect has the effect that the handlebars 39, 40 align themselves between the bearings 41 a and 43 a in their end position when clamping a pressure plate in a relatively stretched position rather. This leads to an increased clamping force, which keeps the system reliable. In summary, the main effects of the novel plate clamping rail can be characterized as follows:

The pressure hose 50 no longer presses directly on the toggle lever drive to open the clamping of the plate clamping rail. The force of the pressure hose 50 is guided centrally via pressure pieces 53 on the compression spring 47. Thus, the force of the pressure hose 52 is given to the compression spring 47 without losses due to deteriorated leverage.

The toggle lever drive used is designed so that it does not overturn over the dead center when the pressure plate 45 is clamped, so that there can be no reversal of the force direction within the movable lower rail 43.

Furthermore, in comparison to systems which overshoot the dead center of the toggle lever drive in an end position at a stop, no clamping force loss must be compensated. This would be necessary because the effective length of the toggle lever drive shortens again after passing through the top dead center and thereby the clamping force is reduced.

The pressure piece is guided in an opening 55 through the toggle lever drive. The plungers 52 thus protrude through the lever segments (links 39, 40), which are thus simultaneously axially guided in their position.

Since two intermeshable pressure pieces 52, 53 are provided per pressure spring 47, the first pressure piece 52 can centrically introduce the spring force when closing on the toggle lever drive. The second pressure piece 53 directs the force of the pressure hose 50 via the first pressure piece 52 against the compression spring 47th

The second pressure piece 53 is designed to be axially displaceable in the first pressure piece 52, so that individual compression springs 47 can be pretensioned via a thread in the interior of the first pressure piece 52 by means of a retaining screw 58, supported on the rail body, in order to carry out assembly, disassembly or repairs. The pressure hose 50 then does not have to be inflated.

The second axially displaceable pressure piece 52 then remains in its position and thus causes no opening of the plate clamping rail. 3

If at least two pressure pieces 52 are guided by a toggle lever drive, this axial displaceability is necessary, since otherwise the second pressure spring in each case is required. 47 would work against the first spring via the toggle package and cause tension forces and damage within the plate tension rail. A tension spring device serves to maintain contact between the loosely interacting elements lower rail 43, upper arm 40 and lower arm 39. Other devices, such as compression springs, are also conceivable.

Attitudinal changes are not necessary per se. Variants of settings for different plate thicknesses are possible. Toggle levers, compression springs and bottom rail can be divided over the format width in different and possibly different width segments. As a result, manufacturing tolerances of the components can be better compensated. A uniform clamping force over the entire clamping range is achieved.

LIST OF REFERENCE NUMBERS

1 plate cylinder

2 cylinder channel

3 pressure plate clamping device, plate clamping rail

4 rail body

5 floor

6 left side boundary

7 right side boundary

8 bearing point

9 lower rail couplings, lower handlebars

10 upper rail couplings, upper link

1 1 lower ends

12 upper ends

13 lower ends

14 upper ends

15 bearing point

16 upper rail

17 bearings

18 recess

19 terminal block

20 plate support

21 pressure plate

22 guide rail

23 pressure room

24 hose

25 recess

26 compression spring

27 recess

28 bellows (pneumatic) 29 compression spring

30 recess

39 lower handlebars

39a lower handlebar end / bearing point of the toggle lever drive in the rail body 40 upper link

40a Upper bar end / bearing point of the toggle lever drive on the lower rail

41 rail body

41 a storage location

41 b guide opening

42 Toggle joint

43 lower rail

43a depository

44 upper rail

45 printing plate, printing form

46 pressure piece

47 compression spring

47a ring groove

47b guide opening

48 bottom part of the annular groove

49 pressure chamber

50 pressure hose

51 Lid

51 a stop surface

52 first pressure piece

52a ring-shaped collar

52b sleeve-shaped extension

52c bore / guide hole / thread

53 second pressure piece

53a effective area

53b bolt-shaped extension mainspring

opening

Kraftleitelement

Stop / retaining element retaining screw

washer

Claims

claims

Device for clamping flexible printing plates (45) on a plate cylinder (1) of a sheet-fed offset printing press with plate clamping rails (3) arranged axially parallel in a cylinder channel (2), with a toggle lever drive for producing a clamping movement with at least one upper and one lower lever element (39, 40) , wherein the lever elements (39, 40) by means of a toggle joint (42) are coupled, and with a spring arrangement which is arranged in the region of the toggle joint (42) acting on the toggle lever drive, so that by the action of the spring arrangement in the Plate clamping rail (3) the clamping movement for pressure plates (45) by displacement of the lever elements (39, 40) is executable in a clamping position, and with one or more, expandable pneumatic or hydraulic elements (50) for opening the plate clamping rail (3) for displacing the lever elements (39, 40) from a clamping position into an opening position associated with the toggle lever drive,

characterized,

a lower rail (43) which carries out the clamping movement in conjunction with the lever elements (39, 40) is provided,

in that the lower rail (43) is arranged displaceably linearly and substantially radially with respect to the plate cylinder (1) with respect to a top rail (44) fixedly connected to a rail body (41) of the plate clamping rail (3), and that for moving the lower rail (43) into one Opening position relative to the upper rail (44) one or more expandable pneumatic or hydraulic elements (50) are provided, which are arranged to displace the lever members (39, 40) from the clamping position into an open position on the the Kniehebeltrieb stressing spring arrangement acting.

Device according to claim 1, characterized in that the spring arrangement is formed by individually arranged compression springs (47).

Device according to claim 1 or 2, characterized

in that the compression springs (47) are supported on the rail body (41) of the plate tension rail (3) and act on a respective first transmission element (52), each first transmission element (52) being longitudinally movably guided on the rail body (41) a compression spring (47) and centrally on the toggle joint (42) is arranged acting.

Device according to one or more of claims 1 to 3,

characterized,

in that the pneumatic or hydraulic elements (50) are connected between a cover (51) connected to the rail body (41) for closing the plate clamping rail (3) and a second transmission element (52) displaceably coupled to each first transmission element (52) against a stop (Fig. 53) are arranged supporting.

Device according to one or more of claims 1 to 4,

characterized in that the expandable elements are designed as pneumatically inflatable, elastic pressure hoses (50).

Device according to one or more of claims 1 to 5,

characterized in that the lever elements designed as a lower arm (39) and upper arm (40) and under a non-positive or positive guidance in an open bearing, which forms the toggle joint (42) are hinged together.

7. Device according to claim 1 to 6, characterized in that the compression springs (47) on a rail body (41) of the plate clamping rail (3) supporting and are arranged displaceable on at least one adjustable adjusting element, in such a way that by means of the adjusting elements the clamping force of the plate clamping rail (3) is adjustable.

8. Device according to one or more of claims 1 to 7,

characterized,

in that the pressure hoses (50) are arranged in such a way that the force components produced during inflation are introduced directly onto the second transmission elements formed as second pressure pieces (53) and without touching the handlebars (39, 40), so that this action causes the pressure pieces (53 ) is directed solely against the compression springs (47).

9. Device according to one or more of claims 1 to 8,

characterized,

in that each of the first pressure pieces (52) projects through an opening (55) in the toggle lever drive (39, 40, 42) with one end opposite the compression spring (47), so that the pressure pieces (52) control the position of the control arms (39, 40). axially in the direction of the plate cylinder (1) in position.

10. Device according to one or more of claims 1 to 9,

characterized,

the second pressure piece (53) is arranged so as to be axially displaceable in the first pressure piece (52) such that each first pressure piece (52) can be prestressed relative to the rail body (41) by means of a retaining screw (58) for selectively biasing the compression spring (47) cooperating therewith is and that at least two plungers (52) by a toggle lever drive (39, 40, 42) are performed. Device according to one or more of claims 1 to 10,

characterized,

that for contact between the loosely cooperating elements lower rail 43, upper arm 40 and lower arm 39, a tension spring or compression spring or mechanical position assurance against the assignment to the rail body (41) is provided.

Device according to one or more of claims 1 to 1 1,

characterized,

in that the toggle mechanisms (39, 40, 42), compression springs (47) and the bottom rail (43) are divided over the format width into different segments.