JP2007277008A - Active sheet induction/sheet guide element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressing means for fixing a sheet, a sheet stream, a web, a printing product or a printing product stream to a carrying means. <P>SOLUTION: This pressing means 5 can be formed as a pressing roller, a presser plate, a presser bar, a brush, a brush rail or a cylinder. For improving handling, the pressing means 5 is formed of one or a plurality of active springs. The spring may be composed of a complex of one or a plurality of piezoelectric actuators, or this pressing means itself can also be formed of the active spring. In a monitoring device to paper feeding, a probe element is formed of one active spring formed of the complex of one or a plurality of piezoelectric actuators in case, or itself is formed of one active spring. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an active sheet guidance / guide element and a monitoring device for use in a rotary printing press or post-printing machine according to the preamble of claim 1 or 2.

  Pressing means such as pressing rolls, pressing plates, pressing bars, brushes, brush rails, or pressing rolls are used in various ways in rotary printing presses, copiers, and post-processing machines for printed products. These pressing means are used to prevent the printed product from being lifted by fixing the printing substrate or the printed product to a conveying device such as a conveying belt or a cylinder for smooth conveyance. The pressing means is also used, for example, to prevent damage to the printed product, for example, to prevent sheet end lifting when the sheet is redirected on a cylinder, for example. The printing substrate referred to in the present invention may be a sheet, cardboard sheet, cardboard sheet, paper or cardboard web, cardboard web, metal plate, plastic sheet, or plastic film web. The printed product referred to in the present invention may be any printing substrate printed by any printing method, such as a folded box cut product, a bonded folded box, a folded printed product, a pamphlet or a booklet, and individual items thereof. It may also be a printed product formed from a printed printing substrate such as

  In addition to being used in printing presses as is known, pressing means are used in many different applications in post-processing equipment for printed products. For example, Patent Document 1 describes a stacker used for a copying machine, which is suitable for separating continuous elements. The stacker includes a conveyor belt, and a holder is attached above the conveyor belt. The holder holds a series of freely rotatable balls that press the seat against the belt. At this time, a divided stack is formed, and the positions are shifted in the lateral direction to separate the printed products from each other. Patent Document 2 describes a presser for fixing a stack of sheet-like materials. This presser is attached to a holding arm that is adjustable in height and can be fixed.

  Patent document 3 describes an apparatus for aligning sheets of recording media. In this case, each sheet is collected one after another on the outer periphery of the drum. A concave portion is provided in the outer peripheral portion of the drum, and a drivable transport roll is provided in the concave portion. The transport roll interacts with a pressing roll that can pivot with respect to the transport roll. The conveying roll and the pressing roll are used on the one hand to press the bundled sheets against the drum and on the other hand to discharge the entire bundle. Various pressing means are also known to support sheet transport from folding machines, assorting machines, and folding box bonding machines. All these applications usually require adjustment of the height of the pressing means or the pressing pressure. On the contrary, these requirements are clearly higher in part than in a printing press. This is because, unlike a planar printing substrate, a folded or stamped or other subsequent processed product is fixed by the pressing means. Depending on the backrest when aligning the signatures of the brochure, the crease or fold angle of the folding box assembly further increases the requirements on the pressing means. This is because the printed products are not flat, and often present in a scale-like fashion.

  The pressing means must satisfy two basic requirements. That is, the pressing means must apply sufficient force to the printing substrate or printed product so that the printing substrate is fixed in the desired position. At the same time, the pressure should not be too great to prevent damage to the printing substrate or printed product.

  Finding a compromise between these two requirements, especially if the printing substrate and the printed product are sensitive to pressure. Particularly difficult is the situation in which the printing substrate or printed product is conveyed as a scaly stream. This is because the pressing pressure changes depending on the number of sheets. Attempts to prevent damage to the print substrate by elastically attaching the pressing means. In most cases, the pressing pressure of such pressing means is adjusted by a fixed or adjustable spring. The adjustment of the spring force is usually done by hand, but this is no longer acceptable with today's highly automated printing and post-processing machines. A suitable representative of such pressing means is disclosed in Patent Document 4 as a pressing plate provided on a side mark and in Patent Document 5 as a pressing roll provided on a conveyor belt in an embodiment.

  Adjustment to the thickness of the printing substrate or the thickness of the printed product is usually done by hand in most known solutions for pressing means. There are certainly solutions that automatically adjust the height of the presser, but these solutions are usually very expensive and expensive.

  Therefore, Patent Document 6 describes a pressing tool for a corrugated cardboard product, which includes a pressing brush, and this brush is fixed to an arm by a fixing rod. In this case, the lever arm is connected to the cam disk via a single bar. In this case, the turning movement is adapted by the control device.

  In order to be able to adjust the top mark of the paper feed mark on the sheet-fed press to the thickness of the sheet being processed, the registration mark is aligned with the feed point made possible by the swivel movement. It is known from Patent Document 7 that the height of the paper spot is adjusted by an adjustment driving device. Accordingly, the registration mark can be moved perpendicularly to the sheet feed table, and the distance between the top mark and the sheet feed table can be adapted to the thickness of the material.

  Patent Document 8 describes an apparatus that adjusts a sheet pressing tool in accordance with a side mark on a sheet material that arrives at a processing place in a printing machine and is conveyed on a sheet feeding table. The height adjustment of the presser is performed by adjusting the presser according to the height of the printing material by using an adjustment driving device.

  The solutions listed so far are very expensive and the pressing pressure cannot be adapted dynamically during the conveying process by adjusting and / or controlling the pressing pressure. Such dynamic matching is useful, for example, when the printing substrate or printed product spreads out in a fan shape or overlaps in a scaly manner. Due to the dynamic fit, the pressing pressure for fixing is sufficient to ensure that the printed substrate or printed product is pressed down at any point, but the pressing pressure is not enough to damage the printed substrate or printed product at any point in time. You can prevent it from becoming too big to be dangerous. In addition, all the adjustable pressing means mentioned so far only control to a fixed reference value. This reference value can certainly be modified later with many pressing means, but is not intended to be changed dynamically. There is also no known automatic correction or adjustment of the pressing means, for example by measuring the pressing pressure. With these features, the setup process should be significantly easier and faster.

  For some applications, the pressing means must also be timed. This timing adjustment is necessary to ensure that the printing substrate or the printed product enters the pressing gap between the pressing means and the conveying device, for example, the rotating shaft, without any trouble. A typical application of such timing adjustment is a timing roll in a sheet feeding device of a sheet-fed printing machine. Patent Document 9 shows a sheet conveying apparatus in a machine for processing a sheet. This device is attached to a timing-adjusted shaft and can be pressed against the conveying shaft with an adjustable pressing pressure. The device comprises a roll mounted for rotation, the roll being mounted for adjustable height and axial movement. Similarly, Patent Document 10 includes an apparatus for conveying a sheet to a printing machine that processes the sheet. This device is attached to the timing-adjusted shaft with an adjustable pressure relative to the transfer cylinder. Patent Document 11 describes one timing roll, and an element capable of adjusting the height of the timing roll is a leaf spring having a predetermined deflection curve. The deflection curve of the leaf spring is calculated so that the pressing pressure can be changed within a predetermined range. As an alternative solution, the height-adjustable element consists of two levers, and the timing roll can be adjusted to the desired pressure via the center of rotation and the compression spring.

  Also in other areas of the printing press, timing-adjusted pressing means are known. Patent Document 12 describes a sheet smoothing device including a single bar above a paper feed plate of a printing press. This bar is movably moved up and down and is located in the gripping end region of the supplied sheet, and is sometimes lifted by the controller when pulling out the sheet by the pre-gripper to smooth the gripping end of the subsequent sheet It is lowered again. Patent Document 13 describes a similar device, but the pressing means is a brush rail whose timing is adjusted.

  It is useful to provide a timing-adjusted pressing means for fixing the sheet to the cylinder for guiding the sheet to prevent the sheet end from being lifted. Fixing the print sheets continuously is advantageous when the entire sheet is to be inspected by a sheet inspection apparatus or when the print sheet is to be printed by an ink jet apparatus. In either case, the change in spacing due to the lift of the end of the sheet results in an error. The problem is that this fixing is performed with a fixed roll. Otherwise, the pressing means comes into contact with the gripper of the cylinder that guides the sheet of the printing press, which may cause vibration. Moreover, contact with the gripper results in increased friction.

  It is generally known that a piezoelectric element can be constructed from a material having an appropriate crystal structure by using a so-called piezoelectric effect. When an external voltage is applied to the piezoelectric and current limiting ceramic, a mechanical reaction of the piezoelectric element occurs. This reaction results in a settable push or pull depending on the crystal structure and voltage supply range. U.S. Pat. Nos. 6,057,049 and 5,075,859 propose, among other things, adjusting the spacing between the probe element and the printing material or printing material stream with a piezoelectric actuator formed from a piezoelectric material.

  Patent document 14 shows the apparatus which conveys a banknote. This device comprises, inter alia, a friction roll in contact with the banknote. This friction roll has an idling function and is for preventing a plurality of sheets from being conveyed simultaneously. The distance from the conveyed object is adjusted by a piezoelectric actuator. This piezoelectric element can show a change in length up to 15 μm, and a change in distance of up to 300 μm between the probe roll and the opposing roll can be obtained from this change in length via a lever transmission mechanism. The device described in Patent Document 14 clearly has a control function, but does not have a transfer function. The conveyance of banknotes is performed by a roll pair different from this apparatus. The probe roll moves slightly up and down by a piezoelectric actuator to ensure that any banknote is conveyed. It is also described in this patent publication that the probe roll is dynamically adapted (timing adjustment) according to the production speed with respect to the conveyed product. This timing adjustment or vertical movement is introduced by a piezoelectric actuator and converted by a lever arm.

  Patent Document 15 describes an apparatus and method for controlling a sheet stream structure or a sheet stream. In this case, at least one probe element is movable in the direction of the opposing pressing element while conveying the sheet to the sheet processing machine. Through this opposing pressing element, a sheet stream that is displaced in a scaly manner or a sheet stream composed of individual sheets is guided, that is, conveyed. This method is advantageous in that the probe element leans against the sheet stream, ie is pressed with a defined force and detects this sheet stream while it is being guided through a machine such as a sheet-fed press. During the monitoring of the sheet stream, the probe element is positioned relative to the sheet stream depending on the momentary thickness of the sheet stream, and the pressing force pressing the probe element against the sheet stream is set to one settable value. Or move constantly to maintain a range of values that can be set. With a suitable sensor system, the path of the probe element is detected, which is moved towards a counter-pressing element, which is preferably fixed, for example formed by a feed tray. This makes it possible to determine or measure the thickness of the sheet stream very accurately, so that double sheets and defective sheets are detected without problems, for example an error signal is output. Furthermore, by using the change in the distance of the probe element relative to the opposing pressing element, and taking into account the instantaneous mechanical speed at that time, it is possible to detect sheets that arrive too early, sheets that are too late, and sheets that are skewed. This method is excellent in terms of high accuracy and has high functional safety. Furthermore, it is particularly advantageous that the pressing force of the probe element relative to the opposing pressing element is kept constant, so that the measurement conditions are not affected by the sheet thickness at that time and are constant. Therefore, measurement of sheet thickness or sheet stream thickness and / or automation of sheet stream monitoring is possible without problems.

  The monitoring device described in Patent Document 15 is characterized in that the probe element can move together with the adjusting device in the direction of the sheet stream. In this case, the adjusting drive device comprises at least one piezoelectric actuator, is formed from this piezoelectric actuator, and at least the first sensor system is provided for detecting the displacement of the probe element that can be displaced from the rest position. It has been. The piezoelectric actuator is attached to a rigid carrier, which is provided at a fixed location relative to the sheet stream. The monitoring device further comprises a piezoelectric actuator, which interacts with at least one lever mechanism, which is connected to the probe element and has at least one lever.

The disadvantages of the above solution are, on the one hand, that the use of separate sensors and piezoelectric actuators is relatively expensive and that there is a loss of measurement accuracy associated with the lever and the lever bearing which can possibly occur. Is to occur. There is a limit to the mechanical monitoring devices used via the lever, especially for very thin paper, so it is usually non-contact, such as capacitive measurement, to sense and control very thin paper Equation measurement methods have been proposed and used. Patent Document 15 does not propose anything about a vibration damping method. The vibration of the measurement system can be caused by impulses caused by the passing sheet edge or printed product edge and by rhythmic movement or resulting from the non-roundness of the probe roll. However, for thin paper, these vibrations result in measurement accuracy that is difficult to use to detect very thin paper thickness differences.
US Pat. No. 5,439,209 German Patent Invention No. 1015552 German Patent Invention No. 19811198 German Patent Application No. 10357864 German Patent Application Publication No. 3145364 German Patent Invention No. 3227092 German Patent Invention No. 4239254 German Patent Application No. 10222055 French Patent Invention No. 2318090 Specification U.S. Pat. No. 1,910,506 European Patent No. 0679593 German Patent Invention No. 3521590 German utility model No. 8703993 specification US Pat. No. 5,443,257 European Patent No. 1172317

  An object of the present invention is a pressing means for a printing press or a post-printing processing apparatus, the pressing pressure of which can be freely selected and remotely adjusted, and can be dynamically changed during the passage of a sheet Is to constitute the means. Furthermore, this pressing means has the possibility of static and dynamic automatic adjustment. In addition, this pressing device can guarantee timing adjustment with little vibration.

  This problem is solved by the features of claim 1 or claim 2.

  Useful developments emerge from the dependent claims.

  The object of the invention is solved by the fact that the pressing means can be moved relative to the printing substrate or printed product by means of an active spring, or the pressing means itself is formed by an active spring.

  The active spring is a composite made of a spring material and a piezoelectric composite film. The active spring can have various structures and can be formed as a leaf spring, a cup spring or a coil spring. Piezoelectric composites are conventional piezoelectric materials, preferably piezoelectric fibers incorporated into a polymer matrix. The piezoelectric fiber and the piezoelectric filament formed therefrom are preferably formed from piezoelectric ceramics, which can be very well incorporated into the polymer matrix in the form of fibers. Incorporating piezoelectric fibers into the polymer matrix provides protection against mechanical and / or chemical loads and also allows for use in flexible applications. Piezoelectric fibers are very well protected from breakage during bending by being incorporated into the polymer matrix. This is because the piezoelectric fiber itself is rather brittle. In a preferred embodiment according to the present invention, the piezoelectric actuator is formed as a flexible film, which can be adapted to the various contours of the spring element, and the piezoelectric composite film can be fixed over the spring material over the entire surface. become able to. Piezoelectric composite films provide a high performance / volume ratio, are light in weight, and require less space. As a result, the piezoelectric composite material can be combined with the spring material to form an active spring. Switching speeds and control speeds are usually above 1 kHz, so that a supply adaptation can be made while the printing substrate or printed product passes.

  This active spring is made of a composite material formed of, for example, a plate spring having a thickness range of 0.1 to 3.0 mm and a piezoelectric composite film. With this piezoelectric composite material, the active spring can be controlled and added with a preload. The properties of the leaf spring are maintained and additional preloading of the spring can be introduced independently of the spring loading. By selecting the spring geometry, it is possible to freely select the ratio between force and path. Since length variations in the range of up to 20% are possible, it can be used in various areas of printing and post-processing machines. The performance of the piezoelectric composite is almost completely inherited by this spring, and the resulting loss is almost only a bending loss.

  The advantage of an active spring is that the structure is simple and that the preload can be changed during the passage of the printing substrate or printed product.

  Next, the present invention will be described in more detail with reference to the drawings.

  FIG. 1 shows a simple embodiment of the pressing means according to the invention. A piezoelectric composite material 2 is bonded to the leaf spring 1 or fixed in another appropriate form. The leaf spring 1 in this case, in a preferred embodiment, comprises a hardened lower surface 3 and is fixed to the mount 4 at its end. On the opposite side, a pressing roll is fixed to the composite body of the leaf spring 1 and the piezoelectric composite material 2. This roll is arranged, for example, facing a conveying means such as a conveying cylinder or a conveying belt. The pressing roll can be moved in a direction toward or away from the conveying means by changing a spring load by the piezoelectric composite material.

  There is a clear difference between Patent Document 14 and Patent Document 15. This is because the piezoelectric composite does not act on the lever mechanism, is not attached to a rigid carrier fixed in place, and is a component of a flexible spring. With this piezocomposite, the springs are controlled and addable preload is applied, thus ensuring the displacement of the pressing means. In a particular feature of the invention, the pressing means is directly connected to the active spring, i.e. the spring acts directly on the pressing means. Accordingly, it is possible to adjust the pressing means having a simple structure with high accuracy. This results in a significantly cheaper structure and the adjustment is also precisely transmitted to the pressing element. This is because this active spring acts directly and there is no need to use further lever mechanisms, often with play. In another advantageous embodiment according to the invention, the pressing means are formed from the active spring itself. In this case, the effect on the printing substrate or printed product is obtained most directly.

  Another advantage of the piezoelectric actuator is that it can be used actively as a piezoelectric actuator and passively as a sensor. In the latter case, a voltage is generated when the piezoelectric element is deformed by a mechanical action, and this voltage is read. The voltage signal read is proportional to the force acting in the case of a pressure sensor and proportional to the deformation acting in the case of a path sensor. In order to measure and control the position movement of the pressing means by the action of the piezoelectric actuator, Patent Document 15 proposes to measure and control the position movement path using a separate sensor. This method allows the formation of a control circuit, but is itself expensive and the overall configuration is expensive and complex. The solution according to the invention therefore proposes to simultaneously use an active spring formed of a spring element combined with a piezoelectric composite film as an actuator and a sensor. In an advantageous manner, in this case the actuator and the sensor are integrated as one part. After all, it is advantageous that no additional components are required as a sensor, thereby first providing cost and space benefits.

  In the first feature of the present invention, the principle of the actuator / sensor, part of the piezoelectric ceramic fiber of the piezoelectric composite film is used as an actuator and the other piezoelectric ceramic fiber is used as a sensor. In this case, there are a large number of piezoelectric ceramic fibers that are used in the actuator mode and operate actively, whereas a few piezoelectric ceramic fibers that are used in the sensor mode and operate passively, or vice versa. . Since the absolute value of expansion is rather small, but the associated load is rather large, in the preferred embodiment, a large number of active piezoelectric ceramic fibers operating in the actuator mode have a small number of passive piezoelectric ceramic fibers operating in the sensor mode. Facing each other. Contact with the outside of the passive fiber and the active fiber is in this case made via separate electrodes, that is to say that readout by the sensor part and actuation by the actuator part are possible separately.

  Alternatively, the spring material can be bonded to two separate piezoelectric composite films. In this case, one piezoelectric composite film operates as an actuator, and the other piezoelectric composite film operates as a sensor. This can be done, for example, by gluing the actuator part to one side of the leaf spring and gluing the sensor part to the opposite side of the leaf spring.

  By simultaneously operating the active spring as a sensor and actuator, the pressing means can always be brought into contact with the printing substrate or printed product without causing excessive pressing. A control device is intermediately connected between the actuator and the sensor, and a closed control circuit is provided. The actuator part of the active spring brings the pressing means into contact with the printing substrate or printed product. A pressure is applied to the spring during contact, and this pressure is measured at the sensor portion. The pressing pressure can then be increased or decreased by a defined value or maintained at a controlled level. The entry or measurement of the sheet thickness can in this case advantageously be omitted completely. In an advantageous application embodiment, the sensor signal for measuring the pressing pressure is filtered with a low-pass filter, so that only the low-frequency sensor signal is used for the evaluation of the pressing pressure. Instead of filtering with a low-pass filter, it is also possible to limit the evaluation of impulses detected by the sensor to only those impulses that exceed a specific pulse amplitude as a threshold value. This procedure prevents the active seat guidance / guide element vibration referred to in the present invention from causing a change in contact pressure. Due to this active and self-adjusting pressing pressure adaptation, even scrambling sheet streams can be transported optimally without individual sheets being subjected to excessive pressure from the pressing means. Each time the scaly irregularities pass, the sensor part receives a large impulse with displacement direction data, and at that time, the actuator means moves the pressing means following the direction determined from the impulse transition, Precise fitting is performed by the control circuit. Then, by learning and storing the obtained value, it can be used in the subsequent manufacturing process. This procedure is clearly advantageous over the inflexible way of controlling with reference values as used in EP 172317. This is because individual parameters such as paper structure, paper hardness and bending stiffness are learned by the automatic learning algorithm.

  In another aspect of the invention, the pressing means timing adjustment in the sense that the active spring not only provides adaptation to various surfaces but also completely lifts the pressing means from the printing substrate surface or printed product surface. Also do. Such timing adjustment is useful for preventing the edges of the printing substrate or printed product from being inclined or hitting when they are inserted into the gap between the pressing means and the conveying means. is there. After passing, the pressing means can be timed again and lowered onto the printed substrate, onto a sheet stream formed from the printed substrate, or onto the printed product. This descent can be done by controlling the reference value or by using the control algorithm described above.

  The active spring can be fully undertaken to adapt to the surface of the printing material and / or to adjust the timing of the pressing element. Thus, an active spring or a device comprising an active spring can be suspended directly on a rigid suspension device, for example a rigid cross member. This has the great advantage that the timing-adjusted shaft and the associated drive, such as used for suspending a timing roll in a sheet-fed paper feeder, for example, can be omitted altogether. Therefore, for example, a sheet feeding device for processing sheets can be clearly constructed at an advantageous cost.

  A double sheet can also be detected by the impulse response value using the above-described apparatus. If a plurality of sheets are sandwiched between the pressing means and the conveying means, or if there is additional material waste, or if there are other obstacles that change the distance from the pressing means, the sensor portion detects it. be able to. If more sheets than expected are pulled in at the same time, the impulse response will be greater than expected, or if other faults occur, such as paper faults, the faults will occur at an unexpected time. Both abnormal events can be detected and identified, for example, by exceeding a threshold. If such a double sheet occurs or if any failure is identified, the printing or post-processing device can be shut down to prevent machine damage in subsequent processing steps.

  A great advantage of using the device according to the invention simultaneously as a timing roll and a double sheet prevention device is that the feeding device of a printing or post-processing machine for processing sheets can be greatly simplified. Currently, such a sheet feeder typically includes separate timing rolls and multiple sheet monitoring devices. By combining the two functions, i.e., the timing roll conveyance function and the multiple sheet monitoring apparatus monitoring function, into one unit, significant cost reduction can be obtained. In addition, the operation of such a paper feeder is significantly simplified. This is because the user only has to adjust one device at best, and in some cases, the adjustment can be omitted altogether if an intelligent control or adjustment function is used.

  When three or more devices according to the invention are arranged across the width of the machine, sheets that arrive too early, too late, or skewed can be detected and the corresponding machine operation can be started. This detection can be done by comparing the point of impulse response of the sensor portion of the piezoelectric actuator with a given reference point. If the impulse occurs earlier than the reference point, there will be a sheet that arrives too early, if the impulse is late, there will be a sheet that arrives too late, and if the impulses are not equal on both devices, then the diagonal sheet Exists.

  Inaccuracies in the pressing element, eg non-circularity of the pressing roll, due to timing adjustment movements and / or due to changes in spacing due to scaly streams and / or vibrations from other parts and / or And / or the surface structure of the printing substrate or printed product may induce vibrations in the system that make it impossible to measure its thickness, at least when the paper is thin. A clue to deal with this would be to make the suspension system for the pressing system as stable as possible. By separating the piezoelectric actuators in the actuator and sensor parts, the impulse response supplied from the sensor part of the piezoelectric actuators can be filtered by, for example, a high-pass filter, and feedback provides these actuator parts with reverse control. Vibration can also be actively prevented. Thereby, a relatively high frequency or high frequency vibration can be actively overcome. This has the great advantage that the suspension of the spring and / or the pressing element does not have to be designed to be very heavy. The lightweight design reduces the weight to be moved, thus improving the system reaction time and also has the positive effect of reducing costs. Such active damping is possible even when the displacement of the suspension is measured with other suitable path measurement systems.

  As shown in FIG. 2, one or more sheet guiding devices (5) or sheet guiding devices (5) according to the present invention can be arranged above the transport roll (6) of the sheet feeding device. In this case, the sheet is lifted from the stack (10) by the suction head (11) of the sheet feeding device, and is taken in between the sheet guiding device (5) and the transport roll (6) according to the present invention.

  As further shown in FIG. 2, one or more sheet guidance devices (5) according to the present invention can be located at one or more locations on a sheet feed stand (8) of a sheet-fed printing press. .

  The present invention further includes providing a sheet guiding device in a sheet feeding plate region of a printing machine for guiding a sheet. This sheet guiding device is disposed above the sheet feeding plate and across the sheet conveying direction, and is movable up and down so that the timing can be adjusted. The seat guiding device can be implemented as a cylinder, bar or brush rail. In such a sheet guiding device, timing adjustment or constant adaptation of the pressing pressure is useful. Otherwise, it will be difficult to separate the sheet to be pulled out from the arrived sheet. This is because if the sheet guidance device is in constant contact, the subsequent sheet underneath may be pulled upward by the sheet being pulled out, partially or across its width. In the case of sheets with very high bending stiffness, the pressure on the printing material can also be very large. This is because the pre-gripper of the printing press that guides the sheet is displaced when the sheet is pulled, and this displacement causes the sheet end to more strongly press the rigid sheet guiding device. For pressure sensitive printing materials such as corrugated paper or plastic film, the surface can be damaged if the pressure is too high. Operators attempt to prevent this damage by setting the sheet guidance device to a higher position, but then the advantageous effect of the sheet guidance device in taking the incoming sheet into the top mark position of the printing press. It becomes difficult to get and even impossible. This is achieved by adjusting the timing of the sheet guiding device and lowering it, that is, when a new sheet arrives at the feeding area of the printing press, the sheet guiding means is lowered by a certain amount and the sheet is pulled out into the printing press. Can be prevented by raising it again by a predetermined amount. According to the invention, this timing adjustment of the seat guiding element is introduced by one or more active springs, or the seat guiding elements are formed by the active springs themselves. Unlike the known solution of mechanical timing adjustment, the user can change the lower and upper points for each fine adjustment, or a reference value can be derived from the thickness of the printing material, for example, Both points can be adjusted based on the reference value. In this case too, it is another advantage that it can be operated with active vibration damping, i.e. the seat guiding element can be designed to be clearly lighter. Therefore, the weight that needs to be moved during the timing adjustment is reduced, which can significantly improve the dynamic characteristics of the timing adjustment.

  In one particular embodiment of the invention, the pressing force of the sheet guiding element is detected by a sensor part of the active spring, and in the control circuit, the pressure applied to the printing material is controlled by control of the actuator part of the active spring. Hold constant within a certain tolerance. This solution offers an advantageous application, especially when processing printing materials with high bending stiffness in a sheet-fed press. Regardless of bending stiffness, format, and printing speed, pressure is always applied to ensure sheet guidance. When the sheet to be carried out is fully withdrawn, there is no pressure applied by the sheet to be carried out, and the active spring lowers the sheet guiding element, thereby ensuring good uptake of the incoming sheet to the top mark.

  The invention further comprises a sheet guiding element according to the invention, which is arranged above the side mark of the sheet press. When a new sheet arrives, the sheet guiding element is lifted by the active spring and lowered during the page pulling operation. This ensures a reliable page pulling process even in the case of wavy printing materials.

  The present invention also includes one or more active sheet guide elements that secure the cylinder guiding the sheet or roll web in a printing press or post-processing machine by applying a pressing pressure. In this case, the pressing pressure can be fighted by the active spring. In one expanded configuration, the active spring may introduce another timing adjustment motion. This may be necessary, for example, in the case of a machine that guides the sheet and the sheet is fixed to the cylinder by a gripper. When the gripper passes under the sheet guiding element, the active spring can always lift the sheet guiding element.

It is a figure which shows the actuator by this invention. It is a figure which shows a sheet feeding apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Leaf spring 2 Piezoelectric composite material 3 Hardened lower surface 4 Mount 5 Pushing roll 6 Conveyance roll 7 Conveyance means 8 Feeding base 9 Conveyance cylinder 10 Stack 11 Suction head

Claims (26)

  In a pressing means for applying pressure to the conveying means to fix a sheet, a sheet stream composed of a large number of continuous sheets, a web, a printed product, or a printed product stream composed of a large number of continuous printed products, the conveying means comprises a sheet A transfer cylinder of a printing machine or a rotary printing machine or a copy machine, a conveyance belt of a printing machine or a copy machine or a post-processing machine, or a gathering cylinder of a copying machine or a post-processing machine, and the pressing means includes a pressing roll, a pressing plate, A pressing means that is a presser bar, a brush, a brush rail, or a cylinder, wherein the pressing means (5) is formed from a composite comprising a spring material (3) and one or more piezoelectric actuators (2). By one or more active springs or by a pressing means itself formed from an active spring Pressing means characterized in that it is arranged so as to be movable in the direction of the conveying means (6, 7, 8, 9) or away from the conveying means by means of a piezoelectric actuator (2) which is a component of the active spring .   In a machine for processing sheets, in particular for monitoring the supply of sheets to a sheet-fed press, at least one probe element arranged above or below the sheet stream and movable in the direction of the sheet stream and in the opposite direction A monitoring device, wherein the probe element contacts the sheet stream only in case of an error, the probe element (5) from the spring material (3) and one or more piezoelectric actuators (2) It is possible to move towards or away from the sheet stream by an active spring formed from a composite comprising, or the probe element (5) itself is formed from an active spring , Monitoring device.   The one or more of the piezoelectric actuators (2) of the active spring are formed from a flexible piezoelectric composite film that is a fixed composite with a spring material (3). The pressing means according to claim 1 or the monitoring device according to claim 2.   3. The pressing means according to claim 1 or the monitoring device according to claim 2, characterized in that an additional addable preload can be applied by the piezoelectric actuator (2) of the active spring.   The pressing means according to claim 1 or the monitoring device according to claim 2, characterized in that the one or more active springs are formed as leaf springs, cup springs or coil springs.   6. The spring material (3) forming one or more of the active springs is formed from a leaf spring having a thickness of 0.1 to 3.0 mm. The monitoring device according to claim 2 or 5, wherein the pressing means.   The piezoelectric actuator (2) in the active spring or the active spring itself operates simultaneously or alternately as an actuator for generating force and / or path and / or as a sensor for measuring force and / or path The pressing means according to claim 1 or the monitoring device according to claim 2, characterized in that:   8. The pressing means or monitoring device according to claim 7, characterized in that the sensor part and the actuator part of the piezoelectric actuator (2) are integrated into one part.   9. Pressing means or monitoring according to claim 8, characterized in that the sensor part and the actuator part of the piezoelectric actuator (2) are each formed from separate piezoelectric ceramic fibers and integrated into one piezoelectric composite film. apparatus.   The pressing means according to claim 9, characterized in that a smaller number of piezoelectric ceramic fibers of the piezoelectric actuator (2) are provided in the piezoelectric composite film as sensor portions and more as actuator portions. Monitoring device.   9. The pressing means or monitoring device according to claim 8, characterized in that the sensor part and the actuator part of the piezoelectric actuator (2) are each formed from a piezoelectric composite film and bonded to the spring material (3). .   An adjusting device is provided together with the sensor portion and the actuator portion of the piezoelectric actuator (2), and a signal from the sensor portion of the piezoelectric actuator can be supplied to the adjusting device, and a control signal can be generated by the adjusting device. The control signal can be supplied to an actuator part of the piezoelectric actuator to produce an action of movement and / or force on or coupled to the probe element (5). The pressing means or the monitoring device according to any one of 7 to 11.   An adjusting device is provided together with the piezoelectric actuator (2) acting as a sensor, a filter device is assigned to the adjusting device, and the signal of the sensor can be supplied to the filter device. The pressing means or monitoring device according to any one of claims 1 to 12, characterized in that the vibration transmitted from the guide element or the conveying element for cutting can be cut off from the signal of the sensor.   An adjusting device is provided together with the piezoelectric actuator (2) acting as a sensor, a filter device is assigned to the adjusting device, and the signal of the sensor can be supplied to the filter device. The vibration transmitted from the guide element or the conveying element for detecting the sensor can be detected from the signal of the sensor, and the control device can preferably supply a control signal for attenuating the high-frequency vibration to the piezoelectric actuator (2) The pressing means or monitoring device according to claim 13, wherein   An adjusting device is provided together with the piezoelectric actuator (2) acting as a sensor, and a control device is assigned to the adjusting device, and a signal of the sensor can be supplied to the control device. 15. The lower and / or upper threshold value of the impulse value of the signal to be transferred, which is generated by the sensor from vibrations transmitted from the guiding element or the conveying element for setting, can be set. The pressing means or the monitoring device according to any one of the above.   When a storage device is assigned to the adjustment device and / or the control device, the signal transition value and / or the impulse transition value of the sensor and / or actuator can be stored, and when the sheet is conveyed, 16. The value according to any one of claims 12 to 15, characterized in that the value can be recalled to control and / or monitor the sensor function and / or the actuator function of the piezoelectric actuator (2). Pressing means or monitoring device.   The adjusting device and / or the control device together with the piezoelectric actuator (2) keeps the force that can be applied from the actuator to the sheet to be guided to a sheet to be guided constant within an allowable range based on the value measured by the sensor. The pressing means or monitoring device according to any one of claims 12 to 16, characterized in that the value of the signal transition and / or impulse transition of the actuator can be generated.   In particular, the pressing means (5) together with the guide element (5) is provided in the sheet feeding area of the sheet printing machine in order to guide the sheet when feeding the sheet printing machine. The pressing means or monitoring device according to claim 17, characterized in that:   In order to guide the sheet when feeding to the sheet-fed printing press, the pressing means (5) together with the guide element (5) is provided in a side mark area for positioning both side edges of the sheet. The pressing means or the monitoring device according to any one of claims 1 to 17, characterized by:   20. Pressing according to claim 19, characterized in that, when feeding a sheet, the pressing means (5) is arranged in the side mark area so as to be able to be pulled up from the sheet guide surface and / or the sheet surface. Means or monitoring device.   The pressing means (5) guides the printing material to a region where the printing material is guided by a sheet-fed or rotary printing machine so that the printing material can contact the cylinder surface by controlling the force. The pressing means or the monitoring device according to any one of claims 1 to 17, wherein the pressing unit or the monitoring device is provided so as to be allocated to a body surface.   22. The pressing means or monitoring device according to claim 21, characterized in that the pressing means (5) is arranged to be pulled up from the surface of the printing material in an interrupted area of the cylinder surface.   The pressing means (5) is formed as a probe element, which probe element is to be guided by the active spring, coupled to the piezoelectric actuator (2) or formed by the piezoelectric actuator itself and / or 23. Pressing means according to any one of claims 1 and 3 to 22, or any one of claims 2 to 22, characterized in that it can contact a sheet or web of printing material to be sensed. The monitoring device according to one item.   The pressing means (5) is assigned to a sheet feeding base (8) for conveying a sheet stream, which overlaps in a scaly manner, to a sheet processing machine in one operation cycle, and the pressing means (5) 24. Pressing according to claim 23, characterized in that it is provided for monitoring the relative position of the sheet with respect to the transport path to the processing machine and / or for monitoring the layering of sheets that are skewed and stacked. Means or monitoring device.   The pressing means (5) is assigned to the transport cylinder (9) of the sheet feed table (8) and transports the sheet stream, which is displaced in a scaly manner, to the sheet processing machine in one operation cycle. Means (5) for monitoring the layer formation of the sheets that overlap in a scaly manner and / or for ensuring that individual sheets from the sheet stack (10) provided in the sheet feeding device are fed to the sheet feed stand (8). And / or the sheet feeding table for guiding the sheet conveyed from the sheet stack (10) on a substantially horizontal plane to the sheet processing machine by descending in the area of the conveying cylinder (9). 24. The pressing means or monitoring device according to claim 23, characterized in that it is provided to change the orientation to the plane of 8).   The pressing means (5) is assigned to a conveying cylinder (6), and the conveying cylinder conveys individual sheets from the sheet stack (10) to the sheet processing machine as a sheet stream that overlaps in a scaly manner in one operation cycle. In order to be assigned to the sheet stack (10) of the paper feeding device (8) and for the pressing means (5) to monitor the layer formation of the scalyly stacked sheets and / or the sheet stack In order to reliably convey individual sheets from (10) to the sheet feeding table (8) and / or to monitor the relative position of the sheet with respect to the sheet conveyance path and / or the conveyance cycle to the sheet processing machine. 24. The pressing means or monitoring device according to claim 23, characterized in that it is provided for the purpose.

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