EP2552685A1

EP2552685A1 - Method for producing material boards in a continuously operating press, and a continuously operating press

Info

Publication number: EP2552685A1
Application number: EP11719164A
Authority: EP
Inventors: Gernot Von Haas
Original assignee: Dieffenbacher GmbH Maschinen und Anlagenbau
Current assignee: Dieffenbacher GmbH Maschinen und Anlagenbau
Priority date: 2010-03-26
Filing date: 2011-03-26
Publication date: 2013-02-06
Also published as: CN102917865A; WO2011116986A1; CN102917865B; DE102010003368A1

Abstract

The invention relates to a method and press for producing material boards in a continuously operating press (1) for pressing press material (16) into material boards, wherein a plurality of press frames (2) are arranged at substantially regular supporting intervals in the press (1). Said press frames connect the upper and lower press tie-bars (14, 15) and support the press plates (3), which are arranged at the top and the bottom in the longitudinal direction of the press (1). At least one upper and/or lower adjusting device (12) is/are provided for adjusting the press nip (13) and/or the pressing power between the press plates (3) and the press frames (2). Two endless steel belts (10) that transfer the pressing power and draw the press material (16) through the press (1) are provided. The belts are guided via driving and tail pulleys (17, 18) around the press tie-bars (14, 15) and are supported by the press plates (3) via stationary or mutually rotating supporting elements rolling with the axes thereof transversely to the belt running direction. The method according to the invention is characterised in that at least one press plate (3, 5) is held during operation of the press (1) at least partly in a clamped position, the clamped position is produced by at least one actuating device (12) operatively connected to the press plate (3, 5), and in the actuating device (12) at least two pressure chambers acting in opposite directions are pressurised with a positive pressure greater than zero. (1406).

Description

Process for producing material plates in a continuous press and a continuously operating press

The invention relates to a process for the preparation of

Material plates in a continuous press after the

The preamble of claim 1 and to a continuously operating press according to the preamble of claim 10.

Presses for compression of pressed material usually have the following structure. A number of press frame forming the base frame of the press has a central opening (window frame) and supports two press plates in this opening. At least one of these press plates can by means of

Cylinder piston arrangements, which are usually supported on the press frame, are adjusted in height and thus at a distance from the second press plate. Due to the arrangement of the press plates and the

Cylinder piston arrangements in the gap of the press frame results in a closed power flow for pressing the pressed material into plate-shaped end products by consecutively running cyclically performed

Pressings. The press frames are separated from each other in most cases, but may also have two or more press frame cross-connecting respectively connecting couplings.

So-called double belt presses are to be regarded as a special case, but the pressed material is not directly with the press plates, but with

CONFIRMATION COPY circulating, the pressed material through the press pulling, brought steel strips in contact. To form a closed power flow, a steel belt runs from the associated press plate supported by with rotating rolling rods through the gap of the press frame, where it is guided in the return outside the press frame. The steel belts are driven and deflected on the inlet and outlet side by drive and deflection drums.

With regard to the press frame, two different systems have been proven, on the one hand a "built" press frame of several parts (modular design), at least one table and a tappet plate and this connecting on two sides pull tabs, known from DE 196 22 213 A1 or a one-piece Press frame in frame construction, known from DE 34 13 396 C2. In addition to the assembly, the main difference between the two frame designs that the cylinder piston assemblies must be located in the one-piece press frame directly between the press plate and press frame, whereas in built press frame also on the

Connecting points, for example, between pull tabs and table and / or ram plate, cylinder piston arrangements can be provided. The

Press plates are usually heated or cooled by flowing fluids depending on the application.

In continuous presses, in addition to clock presses in

the present application is the main focus, go through the Pressed material during the run different process phases. Initially, the compaction takes place almost to nominal size of the finished plate product.

Already here, heat is introduced into the pressed material via the heated steel strips. With increasing temperature the pressed material becomes more elastic, whereby the compression can be done with less effort. From a certain temperature and a corresponding moisture plasticization occurs. The compression generated thereby remains permanent and the restoring forces continue to fall. The initial compaction zone is followed by a heat-through zone, in which the set thickness of the pressed material is typically not changed. In the Durchheizzone only continues to heat until reaching the required setting temperature in all layers of the material to be pressed

brought in. The Durchheizzone follows the setting zone in which the middle layer largely sets. At the end of the press finally follows one

Deaeration zone in which the pressure is reduced so that trapped steam can escape and the vapor pressure is reduced. In the way

said calibration zone, which extends over part of the Durchheizzone to the end of the press, pressure and thickness variations in the press nip must be avoided, since in this area take place the Abbindereaktionen and these fluctuations in the final product have a negative impact on the quality and bending strength.

The presses known in the art have several plunger cylinders across the width of the press for applying the pressing pressure in a press frame on, wherein the press nip adjustment outside return cylinder, preferably one to two times per press plate (approximately every two to five press frame) are arranged. The retraction cylinders can also be used in parts a running transversely to the production direction

Bending moment in the press plate initiate, the retracting cylinders are explicitly not a part of the support structure, here press frame, to be and are arranged to reinforce the bending moment completely outside of the press plates (DE 101 14 379 A1). This has proven itself in principle, but can no longer meet the new requirements for modern thin board productions. It has been found that by introducing the bending moments over a two to four meter wide press plate to high fluctuations arise or the controllability is not optimal. Usually, the press plate is controlled by the way (distance control of the press nip). If a deviation is detected, be it in the middle or on the outside, the bending stress of the press plate is changed by changing the pressure in the plunger cylinder and / or via the outer retraction cylinder. This type of control has many disadvantages. On the one hand, it is found that the distances between the two cylinders can be very wide; on the other hand, although preferably incompressible oil is used in the cylinders, fluctuations in the pressure range over the width of up to 0.5 N / mm ² nevertheless result ,

Particularly problematic is this far from each other bending line (Middle / outside) in the thin plate production with low back pressure from the pressed material out.

As already stated, the previous presses due to the

Efficiency preferably either plunger cylinder for applying a pressing pressure on the pressed material on the tribological system

Press plate, roll bar, steel strip and are by means of a

Return cylinder is reset in position or there are double-acting hydraulic cylinders arranged for lifting / lowering in the different pressure chambers (ring and cylinder chamber) with pressure

be charged.

DE 10 2008 025 176 A1 discloses a method for operating a press and a continuously operating press, which preferably discloses a hydraulic cylinder with associated retraction cylinder in each press frame of the calibration area, usually the last third of the press section in the production direction. In particular, it is provided that the hydraulic cylinders of individual, preferably adjacent, press frames communicate with each other during the pressing in order to obtain an optimum distance control in the calibration range, depending on a thickness measurement to be carried out after the press. This method has proven itself in principle, but also has like other control engineering solutions the problem that the controlled system can be very long. A estimated maximum length for a 50 m long press line and a first press frame in the last third compared to a press fixture results in about 10 m, which corresponds to a 10 seconds control time at a production speed of 10 m / s.

Also, the problem of a necessary fine adjustment of the bending of the press plates or the press nip is not discussed in detail.

For in particular in the light plate production with less than 500 kg / m ³ plate density with or without Schäumungszusätzen it is found that after the main compression and adjustment of the press nip of the back pressure from the pressed material is reduced after the compression area and partly lower than the weight of the upper frame construction , For example, found in an upper piston construction, in which the press plates

Hydraulic cylinders are suspended, already a fundamental pressure on the steel strip, which results from the weight of the press plate.

Basically, this property is even desirable, but it provides for the fundamental entrapment of the rolling rods between the upper

Press plate and the steel strip, which in turn assumes a counter-pressure by the clamping force of the acted upon in the direction of the end faces of the press drive and idler drums.

If now a pressed material mat is introduced into the press nip, the result is the

Problem, especially in the production of thin plates with a low specific back pressure, that in this initial pressure range, a control of the double-acting hydraulic cylinder and / or a Plunger- withdrawal cylinder arrangement can only be roughly performed.

Even a closed-loop control is very difficult to build up very low pressures around this area of the "quasi" zero crossing, which regularly leads to overshoot of the regulation in the control technology implementation during the production of lightweight panels

Thickness variations manifested on the finished material plate.

Also, especially in the production of lightweight panels there is the problem that due to the lack of counter pressure from the pressed material mat out the press plates uncontrolled, usually in the middle of the longitudinal extent

(Production direction), can bend due to internal thermal stresses. In an exemplary upper piston construction with hydraulic cylinders on the upper press plate, it may happen that too little back pressure, despite the distance control on the long sides of the press plates (press nip) the upper and / or the lower press plate in the longitudinal direction (production direction) in the middle of the mat or bending in the direction of the pressed material. It results from the experience of a 0.3 to 2 mm, depending on the plate thickness to be produced, lower material plate thickness in the middle of the material plate relative to the longitudinal side edges. The pressure differences that can occur here are in a range of less than 0.1 N / mm ² , in particular less than 0.05 N / mm ² surface pressure on the pressed material. On such pressure differences on the press plates, the previously known presses, especially the continuously operating presses, can not be set, since these preferably form pressure pads via a plurality of hydraulically interconnected pressure cylinder or the pressure control is close to the zero range.

The invention has for its object to provide a method for pressing material to be pressed, in which it is possible as low as possible

To be able to compensate pressure differences in the pressed material. Next, a press, in particular a continuously operating press, are created, in which the acting force of the hydraulic cylinder can be adjusted as finely as possible, in particular, should be avoided

Pendulum pressure control in the range of very low pressures, respectively, when switching between two directions of force, can be compensated easily. In an extension of the task to use the process or the plant engineering design of the press bending a press plate or the simulation of a bending line due to a

Program or due to the bending of a corresponding one

Heating plate can be simplified.

The solution to this problem for the method is that at least one press plate is held at least partially in a clamped position during operation of the press, the clamped position at least one operatively connected to the press plate adjusting device is realized and in the adjusting device at least two oppositely acting pressure chambers are subjected to a positive pressure greater than zero.

The solution to the problem for a press is that at least part of the hydraulic system of the press is designed such that at least one part of a press plate can be held in a clamped position, at least with one adjusting device.

With regard to terminology, the invention is understood to mean the following terms: Operation of the press is understood not only as a producing operation of a material plate, but also as an idling operation during production changes or test drives, preferably meant the onset or heated state of the press. With a restrained situation, the

hydraulic fixation of a press plate circumscribed with two oppositely acting forces. The continuously operating press, well-known to those skilled in the art, produces an endless strip of material, which is fed to the press by means of suitable splitting devices

Material plates is cut. The term "hydraulic cylinder" is understood to mean a linear pressure unit, which consists of at least one cylinder-piston arrangement and acts by means of hydraulic means, for generating compressive forces. Opposing acting pressure chambers are understood, depending on the type of hydraulic cylinder used such that the forces of at least one double acting actuator opposite to the press plate attack respectively at least partially cancel. An adjusting device is not limited to a hydraulic cylinder, but may also be formed from a plurality of hydraulic cylinders. The teaching of the invention stands out in particular from the prior art that at least two pressure chambers are pressurized and the

resulting force difference, acting on one or at adjacent locations on the press plate, initiating a force in the press plate.

For more complicated arrangements, several hydraulic cylinders may also be interconnected to one "actuator." For example, with 7 or 9 hydraulic cylinders across the width, preferably the outer hydraulic cylinders will be used, with nine hydraulic cylinders 1 + 2 + 3 and 7 + 8 + 9 as one

Regarded adjusting device, in which the pressure chambers of the adjusting devices can be hydraulically connected and the middle hydraulic cylinders 4, 5 and 6 are considered individually controllable and adjustable adjusting devices. The person skilled in the art is hereby required, in accordance with a specification for a continuously operating press, to create the number of hydraulic cylinders and the hydraulic circuit per se in order to meet the requirements of optimum control and regulation. The invention further relates to the space of a pressure cylinder under a pressure chamber, which can be pressurized by means of hydraulic means in order to act on a piston with a force. A double-acting cylinder has in the Usually an annular space (the cylinder contains a piston, so that not the entire cylindrical surface is available as a pressure surface, usually the

Return direction) and a cylinder chamber in which the complete cylindrical surface for pressure transmission is available, mostly used for

Realization of the greatest force of a piston / cylinder arrangement. The different forces do not arise from the direct pressures in the pressure chambers, but from the dimensions of the pressure surfaces of the

Pressure chambers. The term lightweight panels is understood to mean material panels having a weight of less than 500 kg / m ³ , preferably a weight of less than 440 kg / m ³ . With a press plate is a surface, the pressing pressure of the

Stellvorrichtung described uniformly on the rolling rods respectively the steel strip distributing metal plate, which preferably fluid channels for

Temperature level control receives and in particular preferably has a temperature in the three-digit Celsius range during operation. The support elements between the press plates and the endless steel belts may be arranged stationarily as individual rolling bearings or as circumferentially arranged rolling rods. Common both variants have the orientation of

Rolling bearing axes transverse to the production direction. The hydraulic system of a press has at least one control and / or a control device, which supplies the necessary adjusting devices and possibly also other hydraulic means requiring devices of the press with hydraulic pressure and controls accordingly. With the inventive solution for the process and for the continuously operating press, which, moreover, also detached from the process

can be operated independently according to the teaching, the following advantages.

For a production of lightweight plate or thick plates with fillers (plastics, aerogels or the like.) With a low density, the consequence is the previous practice of interconnecting hydraulic cylinders across multiple press frame and / or of several cylinders across the width to so-called pressure pad at least partially, if not completely, leaving and preferably the margins and the

Central area (possibly also divided several times) selectively targeted individually and in particular clamped the press plate in critical areas of the press line, by acting on both pressure chambers of a double-acting cylinder (ring and cylinder space) and / or in the

Application of two oppositely acting cylinders (preferably adjacent cylinders) by pressurizing both cylinders with a pressure greater than zero, wherein the force to be adjusted on the press plate (pressure / train) results from the difference of the two opposing forces from the applied pressure chambers.

In particular, it is now possible in the light plate production, with the arrangement of appropriate hydraulic cylinders and their systems from 10% of Press length at each frame, the press plate at least partially

(For example, only in a track or in the middle of the press plate on the press length) in a clamped position and depending on the occurring bending forces of the press plate to compensate or control so that a uniform thickness of the material plate is formed across the width. Preferably, at least one press plate in the middle (in the production direction) is pulled away from the pressed material.

Preferably in an upper piston construction in which the upper

Press plate with several mounted on the upper press bar

Hydraulic cylinders is held in single and / or double-acting design, there is the problem that acts at a 0.15 m thick press plate, a weight of 0.15 * 7000 kg / m ³ + cylinder or piston weight on the material to be pressed. This results in a quasi-minimal pressure of about 0.05 N / mm ² . This weight always affects the pressed material. At the same time this can

Minimal pressure with conventional presses not or only with difficulty over low values, preferably in the Zentelbereich, changed. It is therefore intended to apply pressure not always always a pressure chamber, for example, the return cylinder with upward pressure chambers or the opposite acting on the press plate pressure chambers for

Application of a pressing force on the pressed material, but it is both oppositely acting on the press plate pressure chambers driven with a positive pressure, which mutually in their effect on the press plate completely (posture) or nearly compensating (force generation). About the forces acting on the piston forces in two opposite directions can now advantageously change by slightest changes in the pressures in the pressure chambers acting on the press plate force in the smallest areas. This is possible precisely in the tenth range of the surface pressure, because no control with pressure of a nearly incompressible medium is close to a "non-pressure", but the change targeted via a proportional valve or a throttle or with a sensitive already under a pre-pressure hydraulic circuit set / In particular, when regulating a

Annular space there is still an increased sensitivity through the opposite the cylinder chamber lower pressure surface.

Preferably, at least the weight of the press plate and partially the associated adjusting devices is compensated at each frame. In addition, the low pressure or the desired press nip (thickness of the material plate) should be set exactly, which is particularly advantageous with clamped driving of at least one cylinder, preferably one or more cylinders in the region of the longitudinal center extension,

is carried out. If it turns out that the opposite

Press plate by a few tenths of a millimeter up to about a millimeter bends (bowls), this or the actuator must not be used to adjust the entire press nip, but should the upper press plate, in the exemplary variant, against the outer Adjust adjusting devices and / or against fixed stops. In particular, in a clamped storage and the outer hydraulic cylinder, this possibility arises even in both bending directions, since the outer

Actuators in both directions (clamped driving) can absorb forces, act as quasi attacks and thus counteract a change in the press nip at a non-occurring change in the pressures in their pressure chambers. The method allows in particular in three or more adjusting devices across the width of a bending of the press plate, which can be set very fine.

In other designs of continuously operating presses, a sub-piston construction is preferably used, with the upper one

Fixed press plate firmly on the upper press bar. The press nip is thereby adjusted by means of the hydraulic cylinder adjustable distance between the two

Pressenholme set, which at the same time also the weight of the

Compensate the ram plates and the hydraulic cylinder. The lower one

Press plate is arranged on at least three transversely

Hydraulic cylinders stored in a press frame and can thus be adjusted upwards. In addition to a floating support while the lower press plate against, preferably outboard, stops (arranged on the lower press member) can be driven and pulled by the hydraulic cylinder down to bend them. For more exact settings of the bending line but is also a clamped Driving style, conceivable at least in the middle of the panel. For this purpose, the press plate is mounted in a floating manner on the adjusting devices and subjected to different pressure in accordance with the proposed pressure changes in at least one hydraulically clamped adjusting device.

In a very design and equipment technically complex

Embodiment of a continuously operating press is provided that in a predetermined range, over at least two press frame, in an area after the compression zone and / or in the calibration range or even over the complete main press area with or without

Compaction zone (inlet area) each actuator, preferably designed as a double-acting hydraulic cylinder or as two oppositely acting plunger, individually driven and there the press plate can be kept in a clamped position.

Preferably, an adjusting device comprising at least one double-acting hydraulic cylinder with at least one cylinder space and at least one annulus and / or at least two oppositely arranged in the direction of action single-acting hydraulic cylinder, each with at least one cylinder chamber can be used. The changes in the pressure in a pressure chamber are preferably via a throttle and / or a

Proportional valve performed. In particular, it is now possible the changes in a pressure chamber, the pressure on the pressed material in one Range of less than 0.5 N / mm ² .

Particularly advantageous is the use of at least three adjusting devices in a press frame, when the outer adjusting devices the

Keep the press plate in a clamped position and the middle one

Adjusting device is used for bending and / or compliance with the plan parallelism against the opposite second press plate. In this case, in at least three adjusting devices in a press frame by means of at least one lying in the vicinity or on the longitudinal center line of the press actuator press plate relative to the longitudinal edges of the press plate by 0.1 to 1, 2 mm down or moved up. Now, a bending stress in the use of at least three adjusting devices in a press frame in a

Press plate are initiated when the pressure is changed in at least one pressure chamber at least one adjusting device. It can be moved to introduce a bending stress in a press plate, only the central actuator in the clamped position and only in a pressure chamber of this actuator, the pressure can be changed. Particularly preferably, at least the outer adjusting devices are controlled according to the path and independently of each other.

In a further advantageous embodiment, several

Hydraulic cylinder combined to form an actuator and together driven. This can be an advantage, especially if more than three hydraulic cylinders on a press frame, if only a regular bend over the longitudinal center line of the press to be performed and the

Example, more than 3 cylinders are arranged. It is arbitrary whether several central Zydraulikzylinder be defined to one actuator or more external or even more than 3 Stellvorrichtugnen a press frame. Preferably, however, the structure will be symmetrical to the longitudinal center line of the press.

Further advantageous measures and embodiments of the subject matter of the invention will become apparent from the dependent claims and the following description with the drawing.

Show it:

Figure 1 is a schematic representation of a continuously operating

Press in side view with a press length L and four simplified technological press areas with particular attention to the arrangement of the press frame according to the prior art,

Figure 2 is a schematic representation of a possible adjusting device on the press plate left as a double-acting cylinder and right as two single-acting cylinder with opposite

Effect on the press plate, 3 is a front view of a built press frame of table and platen and these connecting pull tabs,

FIG. 4 shows a front view of a frame sheet in window frame construction,

Figure 5 is a side schematic representation of the press frame in

rear pressing area of a press line,

Figure 6 is a schematic plan view of the press frame from above with

Representation of a transverse to the direction of production series hydraulic cylinder S1 to S5 on a press frame,

Figure 7 is a representation of an embodiment with five easy on the

Press plate acting plunger cylinder and three associated return cylinders across the width of a press frame and the three actuating devices thus produced,

8 shows a side view of a part of the press frame according to FIG. 7, FIG.

Figure 9 shows an enlarged view of a preferred

Embodiment with three arranged on an upper movable press plate over the width of a press frame adjusting devices and arranged on the lower press rail press plate, wherein the press plates are aligned plane-parallel,

Figure 10 shows the bulging of the lower press plate due to thermal

Expansion of the press plate and / or the press frame insufficient sufficient back pressure in the pressed material and Figure 11 shows the bending of the upper press plate by changing the pressure behavior in the middle actuator.

A continuously operating press 1 according to FIG. 1 consists of an upper and a lower press bar 14 and 15, which are held on a press carrier 19 by means of press frames 2. On the front sides of the

Pressenholme 14 and 15 are inlet side idler drums 18 and

On the outlet side drive drums 17 are attached, around which the steel belts 10 are deflected at the top and bottom and driven. Not shown, at least in this figure, the rolling elements or rollers 23, which are arranged between the flat and 22 in the production direction in series lower and upper press plates 3 and 5 and the steel strips 10 and for a possible frictionless and supported passage of the steel strips 10 through the Press 1 care. The press section L, technologically is understood as meaning the two-sided contact of the steel strips 10 at the top and bottom with the pressed material 16, is thematically in the four zones, compression zone I,

Durchheizzone II, setting zone III and vent zone IV, einteilbar, which are shown only sketchy and in practice merge into each other or even overlap in parts. Basically, however, it should be noted that in the inlet region or the compression zone I the pressed material 16 must first be compressed at high pressure and usually to final dimensions, whereas the outlet side a calibration zone or a holding zone is present, which usually the material plate or the Exiting strand sets in its thickness and rather low holding forces needed. Accordingly, the press frame 2 can be arranged to support the press plate 3 and 5 on the outlet side at a further distance from each other as the inlet side.

Figure 2 shows the exemplary arrangement or execution of a possible adjusting device 12 on a press frame 2. In the left drawing, a double-acting hydraulic cylinder with a piston 30 is shown as adjusting device 12, wherein the adjusting device 12, an annular space 29 and a

Cylinder chamber 28 for pressurization with hydraulic pressure. The corresponding hydraulic circuit is not shown here. The two indicated arrows of the pressure chambers (annular space 29 and cylinder space 28) begin with their vectorial beginning in a pressure chamber and indicate the direction of action of this pressure chamber on the heating plate. To make this clearer, this means that when the annular space 29 is acted upon

Press plate 3 is pulled up, with an increase in the pressure in the cylinder chamber 28, the press plate 3 is pressed down respectively increases the pressure on the pressed material if it is assumed that the press frame 2 are considered as a rigid abutment. In the right drawing is a possible representation of two single-acting

Hydraulic cylinder, preferably designed as a plunger cylinder shown. Again, the two arrows show effect from the pressure chambers in opposite directions, with the deflection of the force on the right Hydraulic cylinder a retraction rod 27 and a cantilever is arranged on the press frame. In this embodiment, this forms the left hydraulic cylinder (double acting) and the two right

Hydraulic cylinder (single acting) in each case one adjusting device 12.

In FIGS. 3 and 4, the two main structural differences are compared with known press frames 2, wherein in FIG. 3 a built press frame 2 consists of at least one slide plate 7, at least one table plate 8 and pull tabs 21 connecting them. In this construction, it is possible to arrange the adjusting devices 12, for example as a double-acting hydraulic cylinder between the pull tabs 21 and the plunger plate 7. An alternative arrangement of Plungerzylindern would be an arrangement of the press frame on both sides arranged return cylinders (not shown here). Preferably, these are also

Actuators 12 on the press frame 2, and thus indirectly on the

Press plates acting, operated in a clamped position to the setting of the press nip 13 gentle and easy to perform. The press plates 3 and 5 are then hinged directly to the ram plate 7 and the table top 8 and form the rolling surface for the rolling rods (not shown) of the continuous steel belts 10, which pull the pressed material 16 through the press 1. Here, as an exemplary embodiment, only a central adjusting device 12 may be provided on the press plate in order to avoid and / or control bending. For more complex press designs, previously preferred Spread found, but at least one press plate 3 and / or 5 supported by adjusting devices 12 and could optionally also against fixed

Attacks are taken when deemed necessary.

Preferably, however, as optional and dashed lines shown at least three adjusting devices 12 are arranged across the width respectively in the press frame 2, of which at least one is driven in a clamped position and in both pressure chambers (ring and cylinder chamber) is pressurized. In particular, preferably the outside / longitudinal side of the

Pressing plates 3, 5 on the press frame 2, a fixed support 11 (black) is arranged, which serves as a fixed point and allows about the central actuator 12, the press plate 3 up or in an opposite arrangement of the actuators 12, the press plate 5 to pull down to prevent and / or achieve a bend. An example of a bend is shown in FIGS. 9 to 11.

According to Figure 4, instead of a built press frame 2 and a window frame construction in the form of a frame plate 9 as

Press frame 2 are arranged. In this application of a

Frame plate 9, the cylinder piston assemblies preferably be hinged directly to the press plates 3 and 5.

FIGS. 5 and 6 clearly show the outlet-side end of a continuously operating press 1 in a cut and simplified side view. and top view, the machine elements between the steel strips 10 and the press frame are not shown in Figure 5. According to FIG. 6, five adjusting devices 12 each are arranged in tracks Si to S5 over the width of the press frame 2. In a particularly preferred embodiment, a plurality of tracks S1 to S ₅ can thus be driven by control technology to adjusting devices 12 in a clamped position, in particular over a complete press plate 3, 5 or over a plurality of press plates 3, 5. Particularly preferred is a comprehensive control / regulation of the adjusting devices 12 in the tracks S1 to S _fifth

FIG. 7 shows an illustration of an embodiment with five plunger cylinders 24 acting on the upper press plate 3 and three associated withdrawal cylinders 25 across the width of a press frame 2 and the three actuators 12 thus formed. Two outer plunger cylinders 24 each having a retraction cylinder 25, the over one

Retraction linkage 27 on the press plate 3 acts an adjusting device 12. The inner / middle plunger cylinder 24 forms with a retraction cylinder 25, an adjusting device 12 from. Further, this Wegaufnehmer 20 are shown that record a change in the way and the

Pressure control of the individual pressure chambers of the actuators 12th

support. Preferably, also the lower press plates 5

Position transducer on to detect any bending. corresponding FIG. 7 shows a side view showing three press frames 2 arranged one behind the other in the direction of production 22.

In FIGS. 9 to 11, conceivable bending scenarios of the press plates 3 and 5 are shown, which are not shown to scale and somewhat exaggerated for clarity. In Figure 9 is a regular operation, preferably a production of a material plate with sufficient back pressure from the pressed material to avoid bending of the press plates.

FIG. 10 now shows the bending of the lower press plate 5, which bulges in the middle and thus significantly reduces the press nip in the longitudinal center region. The bulge may be due to lack of back pressure from the pressed material 16, in particular in a thin plate production and / or due to thermal stresses. Also the press frame 2 below, at built

Press frame here the table top 8, may be due to thermal

Bulge expansion here by a few tenths of a millimeter and the

Press plate 5 with bend. To counteract this circumstance quickly, at least one, in particular in the production of lightweight panels

Actuator 12, preferably all arranged adjusting devices 12, driven in a clamped position and positive pressure in the pressure chambers. After determination of the deflections below, for example by thickness measurement at the output end of the press 1 or by displacement transducer of the lower press plate 5, as shown in Figure 11, the hydraulic pressure in

Cylinder chamber 28 lowered and / or reinforced in the annular space 29. To get a bend are either the two outer Adjusting devices also adjusted in the clamped position, so both pressure chambers (annulus 29 and cylinder chamber 28) are pressurized to counteract the bending moment in the press plate 3 through the central actuator 12 can. At the same time, the two outer ones ensure

Actuators 12 that the press nip remains the same on the long sides. Alternatively, the upper press plate 3 could be based on the outer longitudinal sides against fixed supports 11 (not shown here), which receive the bending moment and allow bending of the press plate 3 by the central actuator 12 upwards.

A press 1 suitable for this purpose is characterized in that at least one part of the hydraulic system is suitable for driving at least one adjusting device 12 in the clamped position by acting on both pressure chambers and selectively changing the pressures in the pressure chambers as required.

Preferably, pressure is released in the case of changes to be set minimally, since this can be better controlled with small quantities of oil

Supply hydraulic pressure at high pressures. In extreme cases, it may be necessary to reduce the pressure in the cylinder chamber 28 to 0. 1406

List of Reference Numerals: DP 1406

1. Press 20. Transducer

2. Press frame 21. Pull tabs

3. Press plate above 22. Production direction

4. Intermediate piece 23. Rolling rods

5. Press plate below 24. Plunger cylinder

6. Fixed bearing 25. Retraction cylinder

7. ram plate 26. support slab

8. Table plate 27. Retraction rod

9. Frame plate 28. Cylinder space

10. Steel bands 29. Annular space

1 1. solid support 30. piston

12th adjusting device

13. Pressing gap

14. upper press bar I compaction zone

15. Lower press beam II Durchheizzone

16. Pressed material III setting zone

17. Drive drums IV Deaeration zone

18. idler pulleys

L pressing section

19. Press carrier

Claims

claims

1. A process for the production of material plates in a continuously operating press (1) for the pressing of pressed material (16)

Material plates, where

- in the press (1) a plurality of the upper and the lower press beam (14, 15) connecting and the top and bottom in the longitudinal direction of the press (1) arranged press plates (3) superimposed

Press frame (2) are arranged substantially at regular support intervals,

- At least one upper and / or lower adjusting device (12) for adjusting the press nip (13) and / or the pressing pressure between the press plates (3) and the press frame (2) and

two endless steel belts (10) pulling the pressing pressure (16) through the press (1), which are guided around the press spars (14, 15) via drive and deflection drums (17, 18) and extend from the press plates (3 ) supported by stationary or with rotating, with their axes transverse to the strip rolling direction supporting elements, characterized in that at least one press plate (3, 5) is held during operation of the press (1) at least partially in a clamped position, the clamped position by at least one with the

Press plate (3, 5) operatively connected actuator (12) realized is applied and in the adjusting device (12) at least two oppositely acting pressure chambers with a positive pressure greater than zero.

A method according to claim 1, characterized in that as adjusting device (12) at least one double-acting

Hydraulic cylinder with at least one cylinder chamber (28) and at least one annular space (29) and / or at least two in

Direction of action oppositely arranged single-acting

Hydraulic cylinders are each used with at least one cylinder chamber (28).

Process according to claims 1 or 2, characterized

characterized in that changes in the pressure in a pressure chamber preferably via a throttle and / or a

Proportional valve to be performed.

Method according to one or more of the preceding claims, characterized in that the changes in a pressure chamber causes the pressure on the pressed material in a range of less than 0.5 N / mm ² . Method according to one or more of the preceding claims, characterized in that when using at least three adjusting devices (12) in a press frame (2), the outer adjusting devices (12) hold the press plate (3, 5) in a clamped position and the middle Adjusting device (12) for bending and / or compliance with the plane parallelism against the opposite second press plate (3, 5) is used.

Method according to one or more of the preceding claims, characterized in that when using at least three adjusting devices (12) in a press frame (2) by means of at least one in the vicinity or on the longitudinal center line of the press (1) lying actuator (12), the press plate (3, 5) relative to the longitudinal edges of the press plate (3, 5) by 0.1 to 1.2 mm is moved downwards or upwards.

7. The method according to one or more of the preceding claims, characterized in that for introducing a bending stress in the use of at least three

Adjusting devices (12) in a press frame (2), in at least one pressure chamber at least one adjusting device (12) of the pressure is changed. Method according to one or more of the preceding claims, characterized in that for introducing a bending stress into a press plate (3, 5) on which at least three adjusting devices (12) are arranged transversely to the production direction (22), only the central adjusting device (12) is moved in the clamped position and only in a pressure chamber of this actuator (12), the pressure is changed.

9. The method according to one or more of the preceding claims, characterized in that at least the outer adjusting devices (12) are regulated by the way and independently.

Continuously working press for the production of material plates by pressing of pressed material (16), wherein

Press frame (2) are arranged substantially at regular support intervals,

- At least one upper and / or lower adjusting device (12) for adjusting the press nip (13) and / or the pressing pressure between the press plates (3) and the press frame (2) and two endless steel belts (10) pulling the pressing pressure (16) through the press (1), which are guided around the press spars (14, 15) via drive and deflection drums (17, 18) and extend from the press plates (3 ) on stationary or with rotating, with their axes transverse to the direction of tape rolling

Supporting support elements, and wherein in the press a

Hydraulic system is arranged for control and / or regulation, characterized in that at least a part of the hydraulic system is designed such that at least with an adjusting device (12) at least a part of a press plate (3, 5) can be held in a clamped position.

Press according to claim 10, characterized in that the pressure chambers of the adjusting device (12) are pressurized independently of each other with pressure.

12. Press according to claims 10 or 11, d a d u r c h

characterized in that in the part of the hydraulic system for controlling or regulating the pressure in the pressure chambers of an adjusting device (12) at least one proportional valve and / or a

Throttle is arranged. Press according to one or more of claims 10 to 12, in particular for carrying out the method according to one or more of claims 1 to 9.