EP3002240A1 - Brake for printed sheets - Google Patents

Abstract

Method for operating a device for braking and positioning a printing sheet in a processing machine, wherein along the feed direction of the sheet at least one means are present which exerts a braking force on the sheet, and so the positioning of the sheet in connection with the operation of a downstream processing station accomplishes, characterized in that a first means is operated for acting on the print sheet pneumatic braking force triggering pulses that at least a second means for providing at least one force acting on the sheet braking force generating frictional force is operated that intermittently by the first and / or second means, generate uniform or oscillating braking forces on the sheet, and that the braking forces are guided by a control unit, which with variable resulting from the queried operating parameters St euerungsprofilen and / or operated by stored control profiles.

Description

The present invention relates to an apparatus and a method for decelerating and positioning a printing sheet in a processing machine with at least one braking force generating means.

This deceleration and positioning of the signature is available for a basic operation, which is preferably associated with the production of folded signatures in a folder, the folder typically being provided with a transverse folding and / or longitudinal folding means.

The printing sheets are typically processed from a roll of paper, which is first printed by a printing press (digital or offset) and then guided inline into the folder, the braking and positioning of the sheet first creates the conditions that the fold qualitatively and consistently during the Whole production can be maintained, even at high beats.

With the assured positioning of the sheet before the folding operation also printed paper rolls can be used. Also loose sheets can be fed isolated to the folding device, which also has to be ensured that a secure previous positioning takes place before the folding device.

State of the art

The folding of the various substrates (papers), particularly in the longitudinal fold, is particularly demanding from a process engineering point of view, since the printed sheet is deflected by 90 ° from the feed direction by means of a sword and fed to a so-called folding roller pair. Before the printed sheet parts are fed by means of a sword or other folding device to the pair of folding rollers, the printed sheet part, typically coming from a Querfalzeinrichtung, must be braked in a very short time (a few milliseconds or fractions of milliseconds) from 0 to the feed rate. In today known Längsfalzeinrichtungen happens either with a signature stop or with a combination of sheet stop and brush.

The purpose of the brush is to decelerate and smooth the incoming printed sheet parts within the brush width. The printed sheet parts usually come with the folded edge (transverse fold) ahead in the Längsfalzeinrichtung. But it can also be unfolded (ie without transverse fold) fed to the Längsfalzer.

The longitudinal folding process is fundamentally state of the art. The main problem with the sheet deflection in the folding rollers is mainly the braking of the printed sheet on the so-called sheet stop. In this case, the entire deceleration energy is generated abruptly by the impact of the sheet at the sheet stop. As a result, the single printed sheet is compressed in the area of the sheet stop, or in the case of a stiff sheet, a portion of the energy is converted in the form of a spring-back.

The compression of the printed sheets, depending on the speed and paper type, can lead to injuries of the folded edge and thus to bad products. When springing back the printed sheets, they can also easily twist relative to the optimum geometric position: during the subsequent sword insertion time, this leads to oblique or parallel folds. To these negative Various measures have already been proposed, which are components of the state of the art, to reduce or eliminate effects.

For example, the brake brush or brushes are in the area in front of the sheet stop. These must each be set to the product thickness. The disadvantage of this solution is that the brake brushes are subjected to a strong mechanical wear and the thickness adjustment on the paper is usually complex. It can also be the feeding upper bands are guided only to the end of the printed sheet part. Thus, a repelling is prevented or the product is returned to the stop again. In this case, however, injuries to the printed sheet at the stop are not prevented. Also conceivable is a combination with the upper solution. Other known systems are actively controlled braking devices that brake the sheet at the end so that they are only aligned at the stop.

Out DE19921169 C2 a device for braking paper sheets has become known. In this device, the products are advantageously braked and stopped at the rear, so that they can be stretched and smooth on the pad, z. B. rest a folding table. The device has a compact and simple construction with few components. This device is easy to control. The device can be used as a sheet brake on folding tables, as a brake in slowing down stations or in front of the compartments of paddle wheels, so that the products, as described, can be processed undamaged. Paper sheets are transported by a non-illustrated conveyor belts, for example, to a folding table of printing machines. These paper sheets may be products cut from paper web cross cutters which may be unfolded or single or multiple folded. These may be collected or unsaved products. On a frame, a carrier is attached, which runs above along the direction of paper travel. At its end facing away from the frame, an electromagnet is arranged on the carrier. In the bobbin an anchor preferably moves perpendicular to the direction of movement and surface of the paper sheets. At its executed to the trajectory end of the armature carries a brake shoe to which a brake pad is attached. The brake shoe is by means of a spring element, for. As a leaf spring made of spring steel or plastic material, resiliently connected by a recording on the carrier. However, it would also be conceivable to use a helical spring which is received directly by the armature and is supported both on the housing of the electromagnet and on a shoulder of the armature. By electrical control of the electromagnet, a magnetic flux field is generated, is pressed by the force of the paper sheet from the anchor on the brake shoe with its brake pad against another, fixed to the support brake lining.

Out DE4307383 A1 is a device for braking bows, especially paper sheets out. The bows are guided by a high-speed band section, consisting of several, spaced apart subbands and upper bands, one after the other to a braking device. While the outlet-side guide rollers of the sub-bands are located in front of the braking device, the upper bands extend further into the region of the braking device. The braking device consists of a arranged below the inlet plane baffle extending over the working width. At the web outlet end of the baffle a slot nozzle is arranged, is blown from the compressed air against the sheet travel direction over the top of the baffle and is directed by its upwardly curved end upwards. The airflow creates a negative pressure that pulls the trailing edge of the sheets down and brakes the sheets at the same time. Immediately following the air nozzle, a machine-wide, circulating lap cloth follows, which is moved at the slower speed. The bends deflected downwards by the air flow from the nozzle release from the top bands and lay on the cloth. In this case, the leading edge of the subsequent, still unbraked printed sheet slides over the trailing edge, it forms a scale flow, which is transported on with the slower filing speed.

Presentation of the invention

The invention is based on the object at a device and method of the type mentioned printing sheets from a high speed in a very short time accurate position, stable and completely decelerate before these sheets are then subjected to the intended further processing.

In most cases, this position-accurate braking is closely related to further processing of the sheet, in which the exact positioning is a prerequisite to achieve the desired quality.

However, there are also cases in which the positionally precise braking of the printed sheet represents only an intermediate step, which does not have to be directly or necessarily in operative connection with a subsequent further processing.

Regardless of which final purpose pursues this positionally accurate braking, the invention is therefore based on the object that on the one hand, the sheets are not damaged or injured in this deceleration, and on the other hand, that their positioning over the entire production always remains an exact.

Starting from a preferably operated further processing, the printed sheets are fed to their positionally accurate braking a folding device, such further processing, as already mentioned, is not exclusive and mandatory to understand.

• Vorzugsweise soll diese Abbremsung durch pneumatische Mittel erfolgen, welche bremskraftauslösende Luftimpulse injizieren, und bei welchen die resultierende Bremskraft im weiteren Sinn direkt und/oder indirekt auf den Druckbogen wirkt.

The invention here proposes a qualitative and economic development of the prior art, in which it is a device and a method goes, with the aim to accomplish a positionally accurate braking of the sheet:

• Preferably, this deceleration is to be effected by pneumatic means which inject braking force-triggering air pulses, and in which the resulting braking force acts in a broader sense directly and / or indirectly on the printed sheet.

In the direct implementation, it is so that the braking force-triggering air pulses are directed directly to the sheet and there implement their effect, the number, strength and place of action of these air pulses are adapted to the given conditions.

In the indirect implementation, it is such that the braking force-triggering air pulses act on at least one mechanical element, which is arranged intermediately between the sheet and ejection source of the air pulse, such that the effective braking effect on the sheet is then effected by said element, wherein such an element may have different dynamic configurations.

In addition, the positionally accurate braking of the sheet in the feed direction can at least partially accomplish by a producible acting on the sheet negative pressure, which can be achieved by suitable provisions within the table-like documents, usually located below the conveyor belts, with effect against the sheet. Thus, the friction between the surface of the table-like documents and underside of the sheet increases in such a way that this frictional force can be preferably used as a fine adjustment for an accurate final positioning of the sheet. As already mentioned above in connection with the air pulses, the number, strength and place of action can also be adapted to the prevailing conditions for the implementation of the negative pressure on the printed sheet.

The two braking forces, so the braking force-triggering pulses on the sheet, they are operated directly or indirectly, and the increase in friction by negative pressure, can be interdependent to each other or control independently, the braking force of the two changed case by case resp. can be adjusted.

Of course, an additional braking force can be accomplished by at least one mechanically activatable element which can be used for fine adjustment, for example, in addition to the force acting on the sheet pneumatic brake force-triggering pulses, such a mechanical element readily by an autonomous control or in the above sense purely by air pulses can be operated.

By means of said braking force-triggering provisions on the printed sheet, a continuous optimization of the applied braking and friction forces can be achieved by using a controlled procedure in which the said precautions are used interdependently or occasionally.

Such an approach, which provides for the inclusion of direct and / or indirect braking and deceleration by triggering additional friction effects on the sheet, particularly advantageous when it comes to supplying the sheet before or after the folding process, for example, a dandruff or to achieve a corresponding Schuppenentflechtung or scale separation.

1. 1. Die positionsgenaue Abbremsung im Sinne eines punktgenauen Stillstandes des Druckbogens wird allein durch bremskraftauslösende Impulse und/oder durch weitere Bremskrafteinbringungen bewerkstelligt. Bei letzteren Mitteln lässt sich dies beispielsweise durch Bildung eines auf den Druckbogen wirkenden Unterdruckes und/oder durch den Einsatz mindestens eines mechanischen Elementes erzielen.
2. 2. Die positionsgenaue Abbremsung im Sinne eines punktgenauen Stillstandes des Druckbogens lässt sich durch bremskraftauslösende Impulse und/oder durch weitere Bremskrafteinbringungen, wie oben unter Ziff. 1 beschrieben, bewerkstelligen, welche dafür sorgen, dass die Zustellgeschwindigkeit des Druckbogens bezogen auf die vorgegebene Endposition soweit abgebremst wird, dass sie betragsmässig annähernd Null ist oder gegen Null strebt. Der endgültige punktgenaue Stillstand des Druckbogens wird dann unter Zuhilfenahme eines Anschlages bestimmt, auf welchen der Druckbogen mit seiner Remanenz Geschwindigkeit auftritt. Da diese Remanenz Geschwindigkeit mikroskopisch klein ausfällt, besteht keine Gefahr, dass die vordere Kante des Druckbogens in Zustellrichtung beim Anprall gegen die Anschlagfläche verletzt werden oder von dieser Anschlagfläche zurückfedern resp. zurückspringen könnte. Diese sanft vollzogene Endstellung des Druckbogens hat darüber hinaus den Vorteil, dass sich dieser ganz an den Verlauf der Anschlagfläche angleichen kann, wodurch daraus eine maximierte genaue Ausrichtung des Druckbogens gegenüber der Anschlagfläche resultiert.

Thus, according to the invention, a plurality of orientations can be provided for pure position-accurate braking in the sense of a punctiform standstill of the printed sheet in the feed direction.

1. 1. The precise positioning deceleration in the sense of a pinpoint standstill of the sheet is accomplished only by braking force triggering pulses and / or by further braking force entries. In the case of the latter means, this can be achieved, for example, by forming a negative pressure acting on the printed sheet and / or by using at least one mechanical element.
2. 2. The precise positioning deceleration in the sense of a pinpoint standstill of the sheet can be determined by braking force triggering pulses and / or by further braking force, as described above under no. 1, which ensure that the feed rate of the printing sheet with respect to the predetermined end position is braked so far that it is approximately zero in magnitude or tends towards zero. The final punctiform stop of the signature is then determined with the aid of a stop on which the signature with its remanence speed occurs. Since this remanence speed is microscopically small, there is no danger that the leading edge of the sheet in the feed direction are injured in the impact against the stop surface or spring back from this stop surface resp. could jump back. This gently completed end position of the printed sheet also has the advantage that it can be fully aligned with the course of the stop surface, resulting in a maximized accurate alignment of the sheet relative to the stop surface results.

Here, the following procedure is relevant: The speed of the sheet is slowed down at about 10 cm before the stop by means of a sheet brake, that this occurs only with a low kinematic residual energy at the stop, wherein the impact of the press sheet at impact <1 m / s is. With such a final speed no injuries of the sheet are possible, and the sheet undergoes no springback because of excessive impact speed.

The course of the deceleration of the delivery speed of the printed sheet can preferably be provided according to an e-function or quasi (similar) e-function, wherein a truncation of the original curve by another mathematical course is also possible. Truncation is generally understood to mean the truncation or separation of something, usually in the figurative sense (truncation of Latin truncare). As an example, it could be stated that the course of the e-function at a certain point is no longer performed monotonically, but in its place, the continuation of the braking process is perceived by another mathematical function.

In both cases described, para. 1 and 2, the dynamics of the combustion-inducing provisions must take into account the way the sheets are transported. If conveyor belts are used for transporting the printed sheets, then the control of all braking-force-inducing provisions must be in operative connection with the kinematic force exerted by the conveyor belts on the printed sheets. Thus, the braking effect by the means provided is basically not in collision with the kinematic forces exerted by the conveyor belts, with certain constellations is not excluded that an at least partial superposition of the two forces (braking force and transport force) is deliberately sought.

1. a) Es lassen sich intermittierende, gleichmässige oder oszillierende bremskraftauslösende Impulse anbringen, welche die Bremskraft direkt, semi-direkt oder indirekt auf den Druckbogen anbringen. Solche Impulse lassen sich mit der nötigen Intensität und Kraftentfaltung vorzugsweise durch den Einsatz einer gesteuerten Luftzuführung erreichen.
2. b) Die bremskraftauslösenden Impulse lassen sich vorzugsweise durch pneumatische Luftimpulse oder reibungsauslösende Elemente bewerkstelligen, wobei auch autonom betriebene elektronisch oder hydraulisch Elemente zum Einsatz kommen können. Auch diese letztgenannten Elemente können eine direkte oder indirekte Bremskraft auf den Druckbogen ausüben.
3. c) Vorzugsweise erfolgen die pneumatisch betriebenen bremskraftauslösenden Impulse durch mindestens einen direkt auf den Druckbogen gerichteten Luftstrahl, der auf ein intermediär oberhalb des Druckbogens angeordnetes flexibles Element bläst, wobei dieses Element mit der Form eines Hebels direkt auf Grund des Luftstrahls nachgibt oder über eine Lagerung beweglich ist.
4. d) Wird die Hebelwirkung des genannten Elementes direkt umgesetzt, so ist beispielsweise von Vorteil, wenn dieses Element aus einem faserverstärkten textilähnlichem Band besteht, womit eine Nachgiebigkeit in Abhängigkeit seiner Federkonstante resultiert.
5. e) Wirkt der Luftimpuls beim Einsatz eines Hebels auf einen Hebelarm, kann die Normalkraft und infolgedessen die resultierende Bremskraft durch Hebelgesetz verstärkt werden.
6. f) Mit den beschriebenen Vorkehrungen lassen sich vorteilhaft auch asymmetrisch zusammengesetzte Falzbögen verarbeiten, ausgehend von der Tatsache, dass solche Falzbögen den Nachteil haben, dass die Masse links und rechts unterschiedliche Werte aufweist. Zu diesem Zweck kann erfindungsgemäss die Kraft des Luftimpulses und infolgedessen auch die daraus resultierende Bremskraft durch automatische Druckregler eingestellt werden. Dabei werden die notwendigen Einstellwerte automatisch von der Steuerung resp. von dem übergeordneten Prozessleitsystem errechnet und umgesetzt.
7. g) Die bremskraftauslösenden Impulse können gleichzeitig oder zeitunterschiedlich mit gleichen oder unterschiedlichen Bremskraftgrössen auf eine vordere und/oder eine hintere Kante des Druckbogens in Zustellrichtung wirken, womit bei dieser Vorkehrung gleichzeitig eine Glättung resp. Streckung des Druckbogens erreicht werden kann.

As regards the technical nature of the braking forces and their integration and use in comparison to an inventive exact positioning of the sheet in the feed direction, the following relationships can be seen:

1. a) It can be intermittent, uniform or oscillating brake force triggering impulses attach, which attach the braking force directly, semi-directly or indirectly on the sheet. Such pulses can be achieved with the necessary intensity and power development, preferably by the use of a controlled air supply.
2. b) The braking force-triggering pulses can be accomplished preferably by pneumatic air pulses or friction-triggering elements, whereby autonomously operated electronic or hydraulic elements can be used. These latter elements can exert a direct or indirect braking force on the sheet.
3. c) Preferably, the pneumatically operated braking force-triggering pulses by at least one directly directed to the sheet of air air blowing on an intermediate above the sheet arranged flexible element, said element with the shape of a lever yields directly due to the air jet or movable over a storage is.
4. d) If the leverage of said element implemented directly, it is for example advantageous if this element consists of a fiber-reinforced textile-like band, which results in a yield depending on its spring constant.
5. e) If the air pulse acts on a lever arm when using a lever, the normal force and consequently the resulting braking force can be increased by lever law.
6. f) With the described arrangements can be processed advantageously also asymmetrically assembled signatures, starting from the fact that such signatures have the disadvantage that the mass has different values left and right. For this purpose, according to the invention, the force of the air pulse and consequently also the resulting braking force can be adjusted by automatic pressure regulators. The necessary settings are automatically made by the controller resp. calculated and implemented by the higher-level process control system.
7. g) The braking force-triggering impulses can act simultaneously or with different time with the same or different braking force on a front and / or a rear edge of the sheet in the feed direction, which at the same time a smoothing resp. Stretching of the sheet can be achieved.

Accordingly, the device for braking and accurate positioning of a printing sheet in a processing machine on means which develop a pneumatic and / or mechanical braking force and / or otherwise frictional force on the sheet along the feed direction of the sheet.

This accurate positioning of the signature is related to the operation of a downstream processing station and is then to be oriented so that accurate positioning is in close interdependence with the operational needs of the downstream processing station.

In particular, the pneumatically operated braking force-inducing pulses and the negative pressure frictional forces can be optimally used when it comes to generating intermittent, uniform or oscillating braking forces on the sheet.

Advantageously, this can be provided by a control unit, which provides control profiles resulting from the requested operating parameters, wherein it is also possible for control profiles stored as required to be retrieved.

The intermittent, uniform or oscillating braking force-inducing impulses to the signature, which can not be achieved only by air delivery, are for a direct, semi-direct or indirect braking action on the signature designed, so that the achievable braking forces can be related to mechanical, electronic, hydraulically operated components.

In particular, when it comes to designing a deceleration and positioning of scale deposited sheet, the application of a force acting on the lower surface of the sheet in the feed direction negative pressure proves to be particularly advantageous because it does not interfere with the arches formed arches is not interfering destroyed, which is always to be feared if only a pure vertical or quasi-vertical air supply is provided. Such a negative pressure can also be controlled well, so that the friction introduced thereby can finely adjust the position of the printed sheets, whereby it is not ruled out in this procedure that further complementary braking forces can be used.

Thus, another possibility for a targeted braking of the sheet along the feed direction is provided, which is that a negative pressure is created on the underside of the sheet, wherein the sheet is printed by the suction effect on the pad, and so for a further braking by friction ensures.

Both the active Lufteindüsung on the sheet and its deceleration by the vacuum-induced suction can be operated both individually and in combination with each other, with an intermittent control between the two is also possible.

Thus, if air-dependent braking forces are used, it is advantageous if each air-operated nozzle is controlled individually by a switching valve, taking into account the feed rate and the nature of the printed sheet.

A controlled interdependence between the individual switching valves increases the targeted effect of the air jets, so that proactively against further on the Sheet resulting operational incongruities in the downstream processing operations Remedur can be created.

• Aufgrund der vorgegebenen Produktionsdaten wie Falzschema, Papiergewicht, Papierbreite, Abschnittlänge, wird der zur Bremsung benötigte Luftdruck berechnet und die Informationen an den automatischen Druckregler geschickt. Dabei können die Druckbogen, je nach Falzschema, auf der linken und rechten Seite unterschiedliche Werte aufweisen.

The invention also relates to a method for a position-accurate braking of the printed sheet in the sense of a pinpoint standstill according to the above orientations 1 or 2, wherein for better understanding, the operational processes of the downstream processing station should be included summarily:

• Based on the preset production data such as folding scheme, paper weight, paper width, section length, the air pressure required for braking is calculated and the information is sent to the automatic pressure regulator. Depending on the folding scheme, the printed sheets may have different values on the left and right sides.

The pressure accumulator in the flow direction before the pneumatic switching valve is filled by means of a pressure regulator to the calculated pressure.

As far as the downstream processing station is a folding operation, the sheet entering / leaving the folding area is detected at the trailing edge by means of a light barrier. At the same time, the light barrier serves for clock-accurate synchronization of the folding blade and thus compensates for any irregularities during the transport of the printed sheet.

Due to the triggered trigger signal, a signal for activating the pneumatic switching valve is triggered taking into account dead time and speed compensation.

Then the air stored in the pressure accumulator is released suddenly, whereupon the air nozzle emits a pulse-like burst of air.

The released air blast can now either directly (unreinforced) act on the sheet or indirectly (reinforced) on a lever (in the present case formed by a fiber-reinforced textile fabric), which transfers the force induced by the air blast force on the sheet.

The printed sheet is pressed onto a table-like base and thus generates by friction an inherent on the sheet transferable braking force.

If required, a braking force can be exerted on the trailing edge of the printed sheet simultaneously or with a time shift. Thus, the mass of the leading sheet-fed part (kinetic energy) causes, due to the energy released by the braking effect, a material stretch which leads to a stiffening effect of the printed sheet.

The braking force dynamics are selected such that the printed sheet is reliably decelerated in the sense of the two orientations 1 or 2 according to the invention as described above, or if it rests against the sheet stop, or the folding blade takes over the sheet. When a sheet stopper is operative, the tucking point can insert slightly delayed.

But it is a strong further orientation of the invention that the exact positioning of the sheet in the sense of a pinpoint standstill can be achieved by the described braking forces and their control even without a stop.

After delivery of the air pulse, the pneumatic switching valve is closed immediately and the pressure regulator fills the air reservoir again with the preset pressure and is available for the next cycle.

However, operation with an air reservoir is not indispensable: the pulsed release of a given amount of air under a certain pressure can also be achieved by a dynamic designed control, which provides directly for a continuous supply of compressed air.

The inventive method for a positionally accurate braking of the sheet can therefore be supplemented by the activation of a negative pressure acting on the sheet.

1. 1. Gegenüber herkömmlichen Lösungen zeichnet sich die Erfindung dadurch aus, dass praktisch keine mechanisch bewegten Teile im Einsatz stehen und somit praktisch keine Verschleisserscheinungen entstehen können, auch nicht bei hohen Taktzahlen.
2. 2. Die zur Erzeugung der kurzen Luftimpulse benötigten Schnellschaltventile sind erprobte Elemente und sind dementsprechend operativ stabil, dies im Gegensatz zu Bremsbürsten nach Stand der Technik, welche immer sehr genau auf die Papierdicke der Druckbogen eingestellt werden müssen, und somit auch einem ständigen Verschleiss ausgesetzt sind.
3. 3. Vorteilhaft ist es auch, dass die erfindungsgemässen Vorkehrungen zur Erzielung einer positionsgenauen Abbremsung im Sinne eines punktgenauen Stillstandes des Druckbogens durch die im Bereich des Falzschwertes an sich minimierte Platzverhältnisse nicht eingeschränkt werden, was im Staufall eine einfache Zugänglichkeit zur Behebung einer Havarie sicherstellt.
4. 4. Die Druckbogen bleiben während der beschriebenen Operationen von jeglicher Beeinträchtigung oder Verletzung verschont.

The main advantages of the invention can be summarized in summary as follows:

1. 1. Compared with conventional solutions, the invention is characterized by the fact that virtually no mechanically moving parts are in use and thus virtually no signs of wear can occur, even at high cycle rates.
2. 2. The quick-change valves required for the generation of the short air pulses are proven elements and accordingly are operationally stable, unlike brake brushes according to the prior art, which always have to be set very accurately to the paper thickness of the printed sheet, and are therefore exposed to constant wear ,
3. 3. It is also advantageous that the provisions according to the invention for achieving a position-accurate braking in the sense of a pinpoint shutdown of the printed sheet are not limited by the minimized in the Falschschwertes space itself, which ensures easy accessibility to repair an accident in storage.
4. 4. The printed sheets remain free from any damage or injury during the described operations.

Brief description of the figures

In the following, the invention will be explained with reference to the drawing, to which reference is expressly made with regard to all details essential to the invention and details of which there is no further details. All elements that are not essential to the immediate understanding of the invention have been omitted, the same elements are given the same reference numerals in the various figures.

Figur 1

eine Gesamtübersicht einer Längsfalzvorrichtung mit Einbezug eines Transportbandes für die Zustellung von Druckbogen;

Figur 2

die Darstellung einer Abbremsung und Positionierung des Druckbogens im Zusammenhang mit der Anbringung eines Luftimpulses als Bremskraft;

Figur 3

die Anbringung einer Bremskraft auf ein intermediäres mechanisches Element

In the drawing shows:

FIG. 1

an overall view of a longitudinal folding device with inclusion of a conveyor belt for the delivery of printed sheets;

FIG. 2

the representation of a deceleration and positioning of the sheet in connection with the attachment of an air pulse as a braking force;

FIG. 3

the application of a braking force to an intermediate mechanical element

Ways to carry out the invention

• Die positionsgenaue Abbremsung im Sinne eines punktgenauen Stillstandes des Druckbogens allein durch bremskraftauslösende Impulse und/oder durch weitere Bremskrafteinbringungen bewerkstelligt wird. Bei letzteren Mitteln lässt sich dies beispielsweise durch Bildung eines auf den Druckbogen wirkenden Unterdruckes und/oder durch den Einsatz mindestens eines mechanischen Elementes erzielen.

FIG. 1 shows the environment of a Längsfalzeinrichtung 100, which consists essentially of a longitudinal folder 101, which is operable with a folding blade 102. Furthermore, the configuration of the folding roller pair 103 emerges from the figure. The operation of this longitudinal folding device 101 is symbolized by the longitudinally folded printed sheet 104 shown. Of course, the folding of the sheet also by a not shown in detail Querfalzeinrichtung take place, which is in operative connection with the shown Längsfalzvorrichtung 101, or can be operated as an autonomous unit. The printed sheet 105 is brought in via conveyor belts 106, and brought to a standstill position exactly at the folding position 107, either via a first provision, according to which:

• The position-accurate braking in the sense of a pinpoint standstill of the sheet alone by braking force triggering pulses and / or accomplished by further braking force inputs. In the case of the latter means, this can be achieved, for example, by forming a negative pressure acting on the printed sheet and / or by using at least one mechanical element.

Or about a second provision, according to which
the positionally accurate braking in the sense of a pinpoint standstill of the sheet by bremskraftauslösende pulses and / or by further braking forces, as described above, accomplish, which ensure that the delivery speed of the sheet is braked so far relative to the predetermined end position, and that they approximate amount Zero or zero. The final punctiform standstill of the sheet is then determined with the aid of a not shown in the figures stop on which the sheet with its remanence speed occurs.

Since this remanence speed is microscopically small, there is no danger that the leading edge of the sheet in the feed direction are injured in the impact against the stop surface or spring back from this stop surface resp. could jump back. This gently completed end position of the printing sheet also has the advantage that it can be fully aligned with the course of the stop surface, resulting in a maximized accurate alignment of the leading edge of the sheet results with the stop surface.

• Die Geschwindigkeit des Druckbogens wird bei ca. 10 cm vor dem nicht näher gezeigten, aber für den Fachmann geläufigen Anschlag mittels Bremskrafteinbringungen soweit abgebremst, dass dieser nur noch mit einer geringen kinematischen Restenergie am Anschlag auftritt, wobei beim Anprall die Geschwindigkeit des Druckbogens < 1 m/s beträgt. Mit einer solchen Endgeschwindigkeit sind keine Verletzungen des Druckbogens möglich, und der Druckbogen erfährt auch keine Rückfederung wegen zu grosser Aufprallgeschwindigkeit.

The following procedure is relevant for this last-mentioned provision:

• The speed of the sheet is braked at about 10 cm before the stop not shown in detail, but familiar to those skilled by Bremskrafteinbringungen that this occurs only with a low kinematic residual energy at the stop, wherein the impact of the press sheet <1 m / s is. With such a final speed no injuries of the sheet are possible, and the sheet undergoes no springback because of excessive impact speed.

The course of the deceleration of the delivery speed of the printed sheet can preferably be provided according to an e-function or quasi (similar) e-function, wherein a truncation of the original curve by other mathematical courses is also possible. Truncation is generally understood to mean the truncation or separation of something, usually in the figurative sense (truncation of Latin truncare). As an example, it could be stated that the course of the e-function at a certain point is no longer continued, and in its place the continuation of the braking course is perceived by another mathematical function.

However, in both of the arrangements described above, the dynamics of the arrangements which give rise to the effect of combustion must take into account the manner in which the printed sheets are transported. If conveyor belts are used for transporting the printed sheets, then a control unit 117 must take into account all braking force-triggering provisions in operative connection with the kinematic force exerted by the conveyor belts on the printed sheets. Thus, the braking effect by the means provided in principle should not be in collision with the kinematic forces of the conveyor belts, with certain constellations is not excluded that an at least partial superposition of the two forces (braking force and transport force) is deliberately sought.

Furthermore, a trailing printing sheet 108 with which the clock-wise operation of the longitudinal folding device 100 is to be shown can be seen from the FIGURE.

• Aufgrund der vorgegebenen Produktionsdaten wie Falzschema, Papiergewicht, Papierbreite, Abschnittlänge, wird der zur Bremsung benötigte Luftdruck berechnet und die Informationen über die Steuereinheit 117 an den automatischen Druckregler geschickt, unter Berücksichtigung, dass je nach Falzschema der Druckbogen auf der linken und rechten Seite unterschiedliche Werte aufweist;

The operation of such a longitudinal folding device in operative connection with an accurate positioning of the printing sheet 105 is as follows:

• Based on the given production data such as folding scheme, paper weight, paper width, section length, the pressure required for braking air pressure is calculated and the information sent via the control unit 117 to the automatic pressure regulator, taking into account that depending on the folding scheme of the sheets on the left and right side different values having;

Furthermore, due to the predetermined production data such as folding scheme, paper weight, paper width, section length, the pressure required for braking the air pressure is calculated to decelerate the sheet 105 and sent the information via the control unit 117 to the automatic pressure regulator 109, taking into account that depending on the folding scheme of Sheet can have different values on the left and right sides.

The introduction of the amount of air on the sheet is made by the air nozzle 110 shown, which acts directly. When calculating the required air volumes, it is simultaneously taken into account that in order to neutralize any flapping movements which may occur in the incoming signature 105, a further amount of air may be required, which is also taken into account. Of course, then it should be taken into account that even after the complete deceleration of the printing sheet 105 further stabilizing air entrainment on the printed sheet 105 could be necessary.

Accordingly, the pressure accumulator 111 lying in the flow direction in front of a pneumatic switching valve is filled by means of pressure regulator 109 to the calculated pressure.

The incoming / fed in the fold area / sheet fed sheet 105 is detected at the trailing edge by means of a light barrier not shown in detail, this photocell is the clock synchronization of Falzschwertes 102 at the same time, the operation of the light barrier and irregularities within the tape transport of the sheet 105 recognizes and on the Control unit 117 compensates.

Due to the triggered trigger signal, a signal for activating the pneumatic switching valve is triggered taking into account dead time and speed compensation.

Then the air stored in the pressure accumulator 111 is released abruptly, whereupon the air nozzle 110 releases a force acting on the sheet 105 pulse-like burst of air.

The released air blast can now act on the one hand directly on the sheet 105, or on a lever (See FIG. 2 , Pos. 112), which transfers the air blast and the corresponding resulting force on the sheet. Of course, it is also possible to provide a configuration in which the air blast acts on both the print sheet 105 and the lever 112, the direct and indirect introduction of braking power also being intermittent and with different pulse intensities of the air pulses (see FIG FIG. 2 , Pos. 114) can be controlled by means of the control unit 117.

The sheet 105 is thereby during the Zustellvorganges and / or during the folding process by the pneumatically induced forces on a table-like Pad pressed and then generated by friction, a braking force on the sheet.

In this case, an additional braking force can be directed to the trailing edge of the printing sheet 105 even if required, simultaneously or out of phase, whereby a stiffening of the printed sheet 105 results due to the material stretching triggered by the braking action.

The braking time (See FIG. 3 , Pos. 115) is selected so that the sheet 105 is reliably decelerated to 0, and, in the figurative sense, even when using a sheet signature stop, as described above. This specification can also be achieved if the deceleration of the print sheet 105 to 0 that fictitious fixed edge ( FIG. 3 , Pos. 113) has reached, in which the folding blade 102 takes over the sheet 105 as intended. Thus, the detection of the print sheet 105 by the folding blade 102 can be adjusted so that this coincides with the fictitious fixed edge 113 of the sheet end.

A not shown in detail possibility for a positionally accurate braking of the print sheet 105 can be achieved by activating an additional braking force, which is based on friction. This can preferably be achieved by the formation of a negative pressure acting on the underside on the printed sheet, whereby this possibility can readily be used in cooperation with the other braking forces explained. FIG. 2 further shows the folding position 116 of the printing sheet 105.

FIG. 3 shows the geometric relationships and the resulting forces in the course of the deceleration of the sheet. Such values, namely the distances 230 and 240 as well as the forces F _impuls (200), _braking (210), _normal (220) occurring during the braking process are of a qualitative nature and are based on a controlled deceleration, with a parameterization of these values for a control / regulation of the deceleration process is also possible.

After delivery of the air pulses ( FIG. 2 , Pos. 114), the pneumatic switching valve is immediately closed and the pressure regulator 109 fills the compressed air reservoir 111 again with the preset pressure and is available for the next cycle.

Claims (27)

Apparatus for braking and positioning a printing sheet in a processing machine, wherein along the feed direction of the sheet at least one means are present which exerts a braking force on the sheet, and so the positioning of the sheet in connection with the operation of a downstream processing station can be accomplished, thereby in that at least a first means for acting on the printing sheet pneumatic brake triggering pulses is designed such that at least a second means for providing at least a force acting on the sheet braking force generating friction force available, that by the first and / or second means intermittent, uniform or oscillating braking forces can be generated on the sheet, and that the braking forces are guided by a control unit, which with variable resulting from the queried operating parameters Steuerungsp rofilen and / or operable by stored control profiles. Apparatus according to claim 1, characterized in that the intermittent, uniform or oscillating braking forces can be converted by a direct, semi-direct or indirect effect on the sheet. Device according to one of claims 1, 2, characterized in that the braking forces by mechanically, electronically, hydraulically, pneumatically caused directly or indirectly directed to the sheet pulses are operable. Device according to one of claims 1-3, characterized in that the braking force acting from above on the print sheet, an increase the friction between a table-like pad and the sheet causes. Apparatus according to claim 4, characterized in that the braking force acting from above on the printed sheet is caused by an air supply and / or by a mechanical element. Apparatus according to claim 5, characterized in that the mechanical element for the exercise of a braking force is arranged autonomously or intermediately with respect to the printed sheet and actuated via the air supply. Apparatus according to claim 6, characterized in that the mechanical element is designed in the form of a lever which is made flexible by its spring constant or yielding over a bearing. Device according to one of claims 1-7, characterized in that on the printing sheet to increase the friction in the feed direction acting on the sheet negative pressure force is accomplished. Device according to one of claims 1-8, characterized in that the deceleration of the sheet is supplemented by a further braking force, which is aligned with the trailing edge of the sheet in the feed direction. Device according to one of claims 1-9, characterized in that the downstream processing station consists of at least one Längsfalzeinrichtung and / or Querfalzeinrichtung. Apparatus according to claim 10, characterized in that at least one folding device is mechanically and / or pneumatically operable. Method for operating a device for braking and positioning a printing sheet in a processing machine, wherein along the feed direction of the sheet at least one means are present which exerts a braking force on the sheet, and so the positioning of the sheet in connection with the operation of a downstream processing station accomplished, characterized in that at least a first means for acting on the printing sheet pneumatic brake triggering pulses is operated such that at least a second means for providing at least a force acting on the sheet braking force generating frictional force is operated to intermittently through the first and / or second means , uniform or oscillating braking forces are generated on the sheet, and that the braking forces are guided by a control unit, which with changeable from the queried operating parameters resulting control profiles and / or operated by stored control profiles. Method for operating a device for braking and positioning a printing sheet in a processing machine, wherein along the feed direction of the sheet at least one means are present which exerts a braking force on the sheet, and so the positioning of the sheet in connection with the operation of a downstream processing station accomplished, characterized in that the positioning in terms of a pinpoint standstill of the sheet is accomplished by braking force triggering pulses and / or by further bremskrafteinbringende means, wherein the latter means is the formation of a negative pressure acting on the sheet and / or by the use at least one mechanical element is accomplished. Method for operating a device for braking and positioning a printing sheet in a processing machine, wherein along the feed direction of the sheet at least one means are present which exerts a braking force on the sheet, and so the positioning of the sheet in connection with the operation of a downstream processing station accomplished, characterized in that the positionally accurate deceleration in terms of a pinpoint standstill of the sheet accomplished by braking force triggering pulses and / or by further braking forces, which are operated so that the feed speed of the sheet is braked so far relative to the predetermined end position that they in terms of absolute value is close to zero or tends towards zero. A method according to claim 14, characterized in that the speed of the sheet is slowed down at approximately 10 cm in front of a stop surface arranged by means of Bremskrafteinbringungen so far that the sheet applies only with a low kinematic residual energy at the stop. A method according to claim 14, characterized in that the predetermined end position is determined by a stop, and that prevails at the impact of the sheet against the stop a final speed of <1 m / s. A method according to claim 14, characterized in that the course of the delay concerning the delivery speed of the sheet is accomplished by an e-function or quasi e-function. A method according to claim 17, characterized in that the curve of the delay has at least one truncation. A method according to claim 12, characterized in that the intermittent, uniform or oscillating braking forces are converted to the sheet by direct, semi-direct or indirect acting means. A method according to claim 12, characterized in that the braking forces by mechanically, electronically, hydraulically, pneumatically driven directly or indirectly directed to the sheet forces are operated. A method according to claim 12, characterized in that the braking forces acting on the printed sheet produce an increase in the friction between a table-like base and the printed sheet. A method according to claim 12, characterized in that to increase the friction on the printing sheet in the feed direction acting on the underside of the sheet negative pressure is accomplished. Method according to one of claims 12, 19-22, characterized in that at least one of the braking forces acting on the printed sheet during the delivery of the printing sheet is supplemented by a further braking force which acts on or in the region of the trailing edge of the printed sheet. Method according to one of claims 12, 19-23, characterized in that at least one braking force is used in connection with the scale formation or scale separation of the printed sheets transported in the feed direction. Method according to one of claims 12, 19-24, characterized in that at least one braking force used for the deceleration of the printing sheet is subsequently used as a transverse folding brake in relation to the printed sheet during the operational process in the downstream processing station. Method according to one of claims 12, 19-25, characterized in that at least one pneumatically operated braking force is controlled by at least one nozzle of a switching valve, taking into account the speed of delivery and the nature of the sheet. Method for decelerating and positioning the sheet in the feed direction and for delaying the sheet during the Falzmäsche retraction and / or against the occurring flap movements in the drawn sheet with the following steps: - Based on the given production data such as folding schedule, paper weight, paper width, section length, the air pressure required for braking is calculated and the information sent to the automatic pressure regulator, taking into account that depending on the folding scheme of the sheets on the left and right side have different values; - Due to the specified production data such as folding scheme, paper weight, paper width, section length, the air pressure required for braking is calculated to decelerate the sheet during Falzmlegt indentation and / or against the occurring flapping movements in the drawn sheet and sent the information to the automatic pressure regulator, taking into account in that, depending on the folding scheme, the printed sheet has different values on the left and right sides; - The pressure accumulator in the flow direction before the pneumatic switching valve is filled by means of a pressure regulator to the calculated pressure; - The incoming / fed in the fold area / sheet is detected at the trailing edge by means of a light barrier, this photocell is the clock synchronization of Falzschwertes simultaneously, the photocell detects irregularities within the tape transport of the sheet and compensated by the controller; - Due to the triggered trigger signal, a signal for activation of the pneumatic switching valve is triggered, taking into account dead time and speed compensation; - Then the air stored in the accumulator air is released suddenly, after which the air nozzle releases a pulse-like burst of air; - The released air blast now acts directly on the sheet or indirectly on a lever, which transmits the air blast and the corresponding normal force to the sheet; - The sheet is pressed during the Zustellvorganges and / or during the folding process on a table-like surface and generated by friction, a braking force on the sheet; - If necessary, an additional braking force is applied simultaneously or out of phase to the trailing edge of the printing sheet, whereby stiffening of the printed sheet occurs due to the material stretching triggered by the braking effect; - The braking time is chosen so that the sheet is safely decelerated to 0, or if it rests uniformly on the sheet stop, or the folding blade takes over the sheet or delayed so far during the folding process; - After delivery of the air pulses, the pneumatic switching valve is closed immediately and the pressure regulator refills the air reservoir with the preset pressure and is available for the next cycle.

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