EP1268329B1 - Device for cutting paper webs - Google Patents

Abstract

An apparatus for cutting paper webs includes a paper feeding means (102), a cutting means (108) and a paper delay means (106) which is arranged between the paper feeding means (102) and the cutting means (108) and delays the paper web (112), which is being fed, in such a manner that a position where the cutting means (108) cuts the paper web (112) is determined on the paper web (112). A buffer means (104) is arranged between the paper feeding means (102) and the paper delay means (106) so as to receive an accumulating length of the paper web (112) in the form of a loop during the delay of the paper web (112). A control means (190) controls the paper feeding means (102) and the paper delay means (106) in such a manner that the loop (195) received in the buffer means (104) does not fall short of a minimum height (h).

Description

The present invention relates to a device for cutting paper webs according to the preamble of the claim 1. In particular, the present refers Invention on a device for cutting paper webs, which is part of a complex paper handling system forms.

Paper handling systems are mainly used by large companies, Banks, insurance companies, service companies, etc. applied. With these companies the paper handling systems are used to process large amounts of paper, such as invoices, reminders, Bank statements, insurance policies or checks. Those to be handled by such a paper handling system In many cases, single papers are made by high-speed printers generated the letters, forms etc. on a Print on the paper web. This paper web is typically can be fed to the printer from a large supply roll and is fed to the paper handling system after printing. Before the paper handling system, however, the appropriate Single paper collation operations etc. can perform, it is necessary that the paper web printed by the high speed printer is cut so that the paper handling system individual Leaves are fed. For this purpose Cutting machines that use a knife or another Have type of cutting device, wherein the to be cut Paper web by means of a paper feed device is fed to the knife. These paper handling systems are often designed so that the handling different Allows papers of different sizes becomes. This flexibility regarding the used Formats through the paper handling system require paper webs can be cut in different formats can.

Another important point in paper handling systems is that depending on a control this Handling systems different numbers of papers are required for respective processes, that is, that one For example, five additional pages are attached to a specific letter whereas another letter is just one Page must also be added. To feed to ensure at a different rate it is necessary that the cutting machine is also able not just to cut different formats, but this also with different speeds the paper handling system supply.

The cutting systems listed above, which are part of a complex paper handling system fundamentally different requirements than so-called rotary cutting machines, such as in print shops the production of daily newspapers. Such Rotary cutting machines are used only for paper webs to cut in a predetermined format. Through the It is the specification of only one format for these machines possible to constant the paper web to the rotary knife Drive speed, the drive speed depending on the fixed format and the rotation speed of the rotary knife is set. The conversion to a different format is with such rotary cutting machines with a lot of effort, because the drive speed of the rotary knife and the feeding speed of the paper web depends on the new format must be set. An automatic Setting the respective parameters to a new one Format requires with such rotary cutting machines a considerable control effort.

In addition to the systems described above, cutting machines are also known in the prior art, in which the paper web is advanced by a desired cutting length 1 by means of a drive over the cutting edge of a cross-cutting device, which can be formed by a lifting or rotary knife, and held in the cutting position , While the paper is now in the cutting position, the cross cutting device cuts off the paper that is fed over the cutting edge. In order to obtain a high throughput (cuts per hour), the paper web must be advanced by the cutting length in the shortest possible time so that the paper web is again in the desired cutting position. In order to achieve this, the paper web must be accelerated to a maximum speed V _max in the shortest possible time and braked again in such a way that when the paper web is at a standstill, the cutting length 1 was advanced.

The disadvantage of this approach is that the very high acceleration and the very high maximum speed a very restless movement of the paper web the feed into the machine. This also leads to that the paper feed has errors due to creasing occur, or even a tear in the paper web occurs. As a result, the maximum possible acceleration and limits the maximum possible speed. 5 is such a cutting machine described in more detail.

The cutting machine 500 includes a paper feed device 502 which is driven by a motor 502a. As can be seen in FIG. 5A, the paper feed device 502 comprises a first drive roller 504 which is driven by the motor 502a at a speed V ₁ . A feed element, preferably in the form of a feed belt 508 or a feed chain, is guided through the drive roller 504 and a guide roller 506. A paper web 512 extends from a supply area 510 via a diversion and guide device 514 to the feed device 502.

In the cutting machine shown in FIG. 5A, the paper web 512 is provided with a perforated edge, in which evenly spaced holes for guiding and driving the paper web are provided. To ensure the drive and guidance of the paper web 512, the guide belt 508 of the feed device 502 has a plurality of teeth 508a which engage with the holes in the perforated edge of the paper web 512. The paper web 512 is fed to a cutting device 516 by means of the feed device 502. The cutting device 516 comprises a so-called drop knife 518, which is essentially in the form of a guillotine. This drop knife is movably guided between two guides 520, 522. The cutting device further comprises a counter cutting edge 524, against which the drop knife 518 moves in the direction perpendicular to the paper web 512 during its cutting movement. The drop knife 518 is actuated by means of a motor 526 which, for example, drives a belt drive consisting of a drive roller 528a, a guide roller 528b and a belt 530 at a speed V ₂ . At an eccentric position of the guide roller 528b is attached one end of a connecting rod 532, the opposite end of which is connected to the drop knife 518. In combination with the drive 526, the connecting rod 532 and the guides 520, 522, the drop knife executes a continuous up and down movement when the motor 526 is driven. In the paper running direction after the cutting device 516, a paper discharge device 534 is provided, which serves to move the cut pieces of paper further. This paper discharge device comprises a drive roller 538 actuated by a motor 536. The motor 536 drives the drive roller 538 at a constant speed V ₃ . In general, the speed V _{3 of} the drive roller 538. is higher than the feed speed of the paper web 512, so that a safe removal of the cut papers is ensured. In addition to the drive roller 538, the paper discharge device 534 comprises a guide roller 540, the cut papers moving between the drive roller 538 and the guide roller 540. The guide roller 540 is biased by a spring 542 to press the paper and against the drive roller 538.

The following is based on that shown in Figures 5B and 5C Diagrams of the basic operation of that shown in Fig. 5A described cutting machine explained in more detail.

At time t = 0, the motor 502a is driven to drive the feeder 502 so that the paper is accelerated to a speed V ₁ . At time t ₁ , the predetermined speed v _{1 is} reached and is maintained until time t ₂ . When the time t ₂ is reached, a position of the paper web 512 in which the cutting is to take place is already in the vicinity of the cutting device 516. The drive of the feed device is controlled in such a way that the paper web 512 is braked from the time t ₂ that this is stopped at time t ₃ . As soon as the time t _{3 is} reached, the motor 526 is driven and accelerated to the speed V ₂ , which is reached at the time t ₄ . This speed is maintained until time t ₅ and the speed is reduced to zero until time t ₆ . During the course of time from t ₃ to t ₆ , the upward and downward movement of the connecting rod 532 results in the cutting movement of the drop knife 518 and the paper web is cut at the desired position. The paper discharge device 534, which is continuously driven by the motor 538 at the speed V ₃ , ensures that the cut paper is transported further. As soon as the time t _{6 has been} reached, the control of the speeds described with reference to FIGS. 5B and 5C begins again and the paper web 512 is fed further in the direction of the cutting device 516 until the corresponding cutting position on the paper web 512 is reached.

With the cutting machines described with reference to FIG. 5A are cutting capacities of up to 19,000 standard forms per Hour or cuts per hour with dimensions of the resulting format of 304.8 (12 inches) x 210 mm.

A disadvantage of the cutting machine described with reference to FIG. 5A is that their operation requires constantly accelerating a large mass, namely the paper web. This constant acceleration and deceleration of the Paper web does not allow continuous operation. This constant accelerations and decelerations lead to the fact that the life of the components used, in particular the used motors 502a, 526, decreases significantly. The attainable Accelerations or decelerations and thus the achievable cutting performance is also limited by that it pulls out when the accelerations are too high the guide hole edges or to tear off the paper web cross-perforated material comes. Furthermore, this leads to jerky Accelerate the paper mass fed to one high noise emissions.

Another problem with these known cutting machines is that because of the slow paper travel speed, through constant acceleration and braking is limited, the suitability for a so-called There is no online operation. The label On-line operation refers to an operating mode a paper web for a high-speed printer is fed, this is printed and directly at speed the printer to the cutting machine becomes.

In the known cutting machines from the prior art a supply stack 510 is therefore provided, into which finished printed paper webs from a remote one Printers are introduced and from there the cutting machine are fed. The slow paper speed also has an upper limit on the performance of such known cutting machines result in the current known machines in the mentioned about 19,000 standard forms per hour or cuts per hour for dimensions the resulting format of 304.8 (12 inches) x 210 mm. .

Another reason for the limitation of Performance of these known machines is that there are performances of over 19,000 cuts per Hour comes to chaotic appearances of the paper web, caused by the constant acceleration and deceleration become and not suppress technologically or are to be controlled.

Paper handling systems are already in the prior art known that a paper web to be cut continuously feed to a knife without cutting the paper web to stop it.

DE-OS 2165194 relates to a method and a device for feeding material to sheet processing and sheet processing Machinery. A web of material is created by means of a pull section fed from a roll of material to a knife cylinder. The material web is cut in such a way that the material web when reaching the knife cylinder by means of Suckers are held on the knife cylinder and initially a so-called paper strip is cut off and the thus generated leading edge of the web that continues is held by the suction cup, by rotating the knife cylinder is passed on to a guide cylinder. The The front edge of the material web is turned on another turn of the cylinder held on the guide cylinder and with the Conveyed web speed until the material web one Cutting area reached in which a bow through the knife is cut off. Between the roll of material and the knife a loop is formed during operation that builds up during the cutting process and after cutting is dismantled again.

DE-PS-723878 relates to a conveyor for railways, especially paper webs, on sheeters and folding machines. A paper web is evenly one over rolls Knife fed, being between the knife and the rollers a suction pad is arranged, which holds the paper web, so that no further transport of paper in the direction of Knife. This holding effect forms one Loop due to the continuously feeding paper.

The paper handling systems described above are one too cutting paper web continuously during the cutting process However, feeds pose a significant problem in terms of the cutting accuracy once the speed the paper feed exceeds a certain value. It was found that the cutting accuracy, whose tolerances are in the tenths of a millimeter range, from depends on the formation of the paper loop. The loop shows from a paper feed speed, the greater than 0.8 m / s, a behavior that can no longer be reproduced. This no longer reproducible behavior of the loop leads to unacceptable fluctuations in cutting accuracy.

Other cutting machines known in the art that e.g. described in DE 196 24 277 include a between a paper feeder and a cutter arranged buffer device that the during the delay of the paper web accrued length of the paper web picks up and at the same time the formation of a loop controls the accumulated paper web and the vibrations the loop dampens, and for a reproducible loop behavior leads.

The disadvantage of this device just described is in that the loop with high during the feed phase Speed is stretched so that despite the damping don't let the popping noises be avoided. Further each of these stretches represents a significant mechanical Strain on the paper web, which is disadvantageous is that there is a risk of tearing the paper web hides, or leads to creasing, which leads to problems leads when feeding the paper web.

The present invention has for its object a improved device for cutting paper webs too create that has a high performance simple and inexpensive way to implement is high at high paper feed speeds Has cutting accuracy and mechanical stress the paper web is reduced.

This object is achieved by a device according to claim 1 solved.

The present invention provides an apparatus for Cutting paper webs with a paper feed device, a cutting device, a paper delay device, a buffer device and a control device. The paper delay device is between the paper feeder and the cutter arranged and delayed the fed paper web in such a way that a position is determined on the paper web at which the cutting device cuts the paper web. The buffer device is between the paper feeder and the paper retarder arranged to during the delay of the paper web is an accumulating length of Record a paper web in the form of a loop. The Control device controls the paper feed device and the paper delay device such that the recorded in the buffer device Loop does not fall below a minimum height.

Generally speaking, the present invention relates to one Machine for cutting an endless paper web with and without transport hole edges, in which the paper web by one Cutting length 1 over the cutting edge of a cross cutting device advanced and during the duration of the cut in this position is held. The paper webs to be processed are either pre - folded as a stack, are from a roll or are processed online by a printer fed.

The device according to the invention decouples the high dynamics the paper feed for cutting from the paper feed in the machine and thus allows a higher acceleration and maximum speed when feeding the paper web into the Cutting position within the machine at a substantial lower acceleration and maximum speed at the Feed the paper web into the machine. Will the device operated in continuous operation, which 'by a continuous Sequence of advancing and cutting marked an almost continuous paper feed can be achieved become. Furthermore, the loop is never complete is reduced, so avoid stretching the paper is ensured that no unnecessary mechanical Loads during the feed phase by the Stretching can be exercised on the paper, so the danger errors due to tearing or wrinkling of the paper web be reduced.

An advantage of the present invention is that the errors just described, e.g. the creasing or the tear of the paper web, further reduced thereby be that the dynamics of the movement of the paper web at the Paper feed into the machine is reduced. Another The advantage is that due to the avoidance of a complete stretching of the paper web in the feed phase the noise generated by the fed paper web is reduced becomes.

Another advantage of the present invention is that a feed of the paper web with essentially constant speed is possible when the paper web to determine the position at which the cutting takes place should be delayed in the short term.

The advantage of the present invention is that due to the uniform feeding speed of the paper web no constant acceleration and deceleration of the paper web is more necessary, so that a constant on / off switching the motors can be dispensed with, resulting in a significant increase in the life of these motors and the other components.

Another advantage of the present invention is that the device according to the present invention the paper running speed for machines from the State of the art with a double paper running speed can be driven. This leads to a doubling the performance of devices according to the present Invention is 24,000 cuts per hour.

Yet another advantage of the present invention is there in that by feeding the paper web with constant Speed the device according to the present Invention driven in a continuous operation can be, which means that this is right at the exit a high-speed printer can connect, so that the rearrangement and temporary storage of the paper web eliminated.

Preferred developments of the present invention are defined in the subclaims.

Fig. 1

ein erstes Ausführungsbeispiel der erfindungsgemäßen Vorrichtung;

Fig. 2

eine vergrößerte Darstellung der Puffereinrichtung für das in Fig. 1 dargestellte Ausführungsbeispiel;

Fig. 3

ein zweites bevorzugtes Ausführungsbeispiel der vorliegenden Erfindung;

Fig. 4

eine vergrößerte Darstellung der Puffereinrichtung für das in Fig. 3 dargestellte Ausführungsbeispiel; und

Fig. 5A - 5C

eine Darstellung einer Schneidemaschine nach dem Stand der Technik.

Preferred exemplary embodiments of the present invention are explained in more detail below with reference to the accompanying drawings. Show it:

Fig. 1

a first embodiment of the device according to the invention;

Fig. 2

an enlarged view of the buffer device for the embodiment shown in Fig. 1;

Fig. 3

a second preferred embodiment of the present invention;

Fig. 4

an enlarged view of the buffer device for the embodiment shown in Fig. 3; and

5A-5C

an illustration of a cutting machine according to the prior art.

1, a first is preferred below Embodiment of the present invention described in more detail.

Fig. 1 shows the schematic representation of a cutting machine 100 according to a first embodiment of FIG present invention. The cutting machine 100 includes one Feed device 102, a buffer device 104, a Conveying device 106 and a cutting device 108, that in a conveying direction indicated by arrows 110 , the paper web 112 are arranged one after the other.

The feed device 102 comprises a pair of drive rollers 114a, 114b. The drive roller 114a is driven by a motor 116 driven as schematically by the connection 116a is shown. The drive roller 114b is on one "L" -shaped support element 118 arranged over a Bearing 120 is rotatably mounted. That is via a spring 122 Carrier element 118 and thus the drive roller 114b over the Bearing 120 biased against the drive roller 114a and pushes against it.

The paper web is between the drive rollers 114a and 114b 112 passed through which through the two roles 114a, 114b is driven. The paper web 112 is from a - not shown - paper supply, for example in the form of a pre-folded stack or a roll in Direction of the feed device 102 fed, this additionally a deflection and guide plate 124 for proper Feed the paper web 112 to the feeder 102 has.

The buffer device 104 comprises a bottom plate 130 which essentially from the feed device 102 to the conveyor 106 extends. In the area where the paper web is to be taken up in the buffer device, the bottom plate has a plurality of openings 132, that allow air to pass through. In the case of FIG. 1 illustrated embodiment at least the paper web is at rest in the areas adjacent to the feeder 102 and the conveyor 106 on the floor pan 130, and air passes through openings 132 is generated by a fan 134 which is below the floor panel 130 arranged in the area of the buffer device 104 is. The bottom plate 130 forms a lower guide device the buffer device.

In addition to the bottom plate 130, the buffer device 104 includes a first upper guide 136 and a second upper guide device 138, each as guide plates can be trained. The first guide plate 136 extends from the buffer device 104 to the feeder device 102 and is bent such that the guide plate 136 essentially in the area of the buffer device 104 perpendicular to the conveying direction 110 of the paper web 112 is arranged and in the area of the feed device 102 essentially parallel to the conveying direction 110 is arranged. The guide plate extends in a similar manner 138 from the buffer device 104 to the conveyor device 106, the guide plate 138 being bent in this way is that it is essentially in the area of the buffer device 104 arranged perpendicular to the paper conveying direction 110 and essentially in the area of the conveyor 106 parallel to the conveying direction 110 of the paper web 112 is arranged.

The buffer device 104 further comprises a sensor device 140 in the illustrated embodiment by a light emitting diode or a laser diode 140a is formed, which is arranged adjacent to the guide plate 138 is. The diode 140a emits light in the direction of the first guide plate 136 and on one arranged thereon reflective element 140b, which reflects the light beam reflected back to a detector 140c, which in turn is adjacent is arranged to the guide plate 138. The sensor device 140 is used to determine a height in the To determine buffer device 104 forming loop, wherein in Fig. 1 an example of a minimum and a maximum Loop height of the building paper web is shown is. The sensor device 140 detects a height h of the paper loop 195 in the buffer 104 and inputs corresponding detection signal to the controller 190. The "height" of the loop is the distance it is around extends in a direction perpendicular to one Plane in which the paper web 112 is fed and cut will is.

1 also shows a second sensor device 150, between the buffer device 104 and the conveyor 106 is arranged which is a light emitting Element 150a, e.g. a laser diode or a light emitting Diode, and includes a detector element 150b. The presence can be determined by means of this sensor device a paper web and / or format recognition features arranged thereon be detected to control the cutting device serve.

The conveyor 106 is by a pair of drive rollers 160a, 160b formed, which is similar in structure to the pair of drive rollers 114a, 114b. A motor 162 drives it Roll 160a as shown schematically by connection 162a is shown. The drive roller 160b is at an "L" shape Carrier element 164 arranged, which is rotatable at 166 is stored. The support element is via a spring 168 164 and thus the drive roller 160b against the drive roller 160a biased. Between the drive rollers 160a and 160b the paper web 112 moves through it. The paper web will through the conveyor 106 towards the cutting machine 108 moves, which also serves the paper web 112 to stop when reaching a cutting position.

The cutting device 108, shown only schematically comprises a lifting knife 170 which is guided by two guide devices 172, 174 is performed. Between the knife 170 and a counter cutting edge 176, the paper web 112 is passed through. The knife 170 is connected via an active connection 178 an actuator 180 connected, which in turn can be driven via a motor 182, as is the case with the connection 182a is shown.

The individual drive elements 116, 162 and 182 of the cutting device 100 by a control device 190 driven, this control device on the one hand ensures that in the feed phase the paper web around the Length 1, which represents the desired cutting length, advanced is pressed and then the cutting of the paper web is actuated becomes. On the other hand, the control device 190 sure that the accumulated in the buffer device Paper loop does not fall below the minimum height a suitable control of the corresponding drive elements.

Furthermore, there is a paper discharge device (not shown in FIG. 1) provided in the paper direction after the Cutting device is arranged. The paper discharge device includes e.g. a pair of drive rollers between which the cut paper is guided.

The paper web is fed during operation 112 into the machine 100 and the feed of the paper web 112 in the machine with stop for cutting through the two separate Drive units 102, 106, ie the drive "inlet" with motor and the drive "feed" with motor.

The "inlet" drive 102 pulls the paper web 112 into the Machine 100 and feeds the paper web 112 into one Loop 195 in the buffer device 104. The loop forms between the loop guide plates 136, 138 and when a maximum height of the loop is reached, the Control device 190 that the drive "inlet" 102nd is stopped.

During the drive "feed" 106 the paper web 112 under the cross cutter 108 with high acceleration and Advancing speed by the cutting length 1 causes the drive "inlet" 102 at the same time the re-feeding of the Paper web in the loop 195 of the buffer device 104.

The "feed" drive 106 preferably runs at a higher rate Maximum speed as the drive "inlet" 102, so that the loop 195 between the guide plates 136, 138 first dismantles. During the time of the drive "Feed" 106 delays the paper web to cut off to effect the advanced path 112 is building the loop in the buffer device 104 again.

The advantage of this arrangement is that the high dynamics of the paper feed for cutting essentially limited to the paper web stored in the loop. The fan 134 supports one from below even and calm loop formation and dampens at the same time the movement of the paper in the loop.

The drive control 190 causes: while the paper web 112 from the drive "feed" 106 um a cutting length 1 is advanced, the loop height Not less than the minimum. This will make an undesirable Stretch and thus unwanted bangs and an even more undesirable mechanical load on the paper web safely avoided.

According to a further exemplary embodiment of the present According to the invention, the control device 190 is also designed in order to reach a maximum loop height if the drive "feed" 106 is stopped, ie when cutting or when cutter 108 is stopped, one does not exceed the maximum height.

In continuous operation of the device 100, i.e. cyclical Feed and cutting, the drive control 190 provides Feed speed so that there is an almost constant Sets the speed of the incoming paper web 112.

The advantage of the embodiment described in Fig. 1 is in that, unlike those from the prior art Technology known devices, a full extension the paper web during the feed phase of the paper web 112 avoids, and so the associated disadvantages. Another The advantage is that, as can be seen, none additional stamp element or other stop element is provided, but the required paper delay is carried out by the conveyor 106, by means of which the paper delayed or stopped during the cutting process becomes.

2 is an enlarged view of the buffer device shown. Furthermore, they are immediately before and after conveyor devices 102 arranged in the buffer device and 106. 2 are those based on FIG. 1 elements already described with the same reference numerals provided, and a new description of the same takes place Not. As can be seen, the drive roller is 114a the feed device 102 mounted on a shaft 200, on which a pulley 202 is arranged. Over a strap 116a is the wheel 202 with the motor 116 (not shown in FIG. 2) connected.

Similarly, the drive roller 160a is the conveyor 106 arranged on a shaft 204 which is a pulley 206 which does not have a belt 162a with the Motor 162 shown is connected.

Another preferred one is described below with reference to FIG. 3 Embodiment of the cutting machine according to the invention shown, which is similar to that of FIG. 1. Instead of the double action of the drive device 106 for conveying and decelerating the paper web realizes this embodiment this functionality in two separate facilities. The buffer device 104 additionally comprises a hood to further dampen vibrations support. The functionality of the buffer device and the control of the individual motors is similar to the embodiment shown in Fig. 1, so that ensured is that the paper loop in the buffer 104 is a does not fall below the minimum height.

The cutting machine 300 comprises a feed device 302, a cutting device 304 and one between the Feeder 302 and cutter 304 arranged paper retarder 306. The paper feeder 302 carries a paper web 308 with in substantially constant speed. The paper delay device 306 delays the feeding of the paper web 308 to the cutting device 304 such that on the Paper web 308 is a position where the Cutting device 304 performs the cutting of the paper web. The direction of paper travel is illustrated by arrow 310.

The feed of the paper web 308 can, for example, from a high speed printer (not shown). The feed takes place via a deflection and guide device 312. In the embodiment shown in FIG. 3 is the paper web 308 with a perforated Provided edge in which evenly spaced holes are arranged by means of which the paper web is driven and to be led. The feeder 302 includes a drive roller 314, a guide roller 316 and a through the Drive roller 314 and the guide roller 316 guided feed element 318. Element 318 is with a plurality of Teeth 318a provided with the in the perforated edge of the Paper web 308 arranged holes engage and the Guide and drive paper web 308 in this way.

Between the feeder 302 and the paper retarder 306 a buffer device 320 is provided, which serves to record the length of the paper web, that during the deceleration of the paper web by the deceleration device runs. An example of the buffer facility is described in more detail below with reference to FIG. 4.

The buffer device comprises a lower guide device 322, which is referred to as the floor panel, and an upper guide device, that of two guide plates 324a and 324b consists. Between the lower and the upper guide device the paper web 308 to be cut moves. Further The buffer device 320 comprises a cover 324c. On the lower guide device 322 there are two nozzles 326a, 326b arranged, through which air preferably exits. The Nozzles are provided for air between the paper web 308 and blow the lower guide 322 while paper retarder 306 the path of the paper web 308 delayed so that the paper web 308 is even without causing undesirable distortions or Kinking the paper web 308 comes. The nozzles 326a, 326b can be controlled so that this only during activation the delay device are effective and during the movement of the paper web 308 by the delay device 306 are not activated.

The function of the lower and upper guide device and the hood is described below with reference to FIG. 4, in the same elements with the same reference numerals are. The nozzles are not shown in FIG. 4, to keep the presentation clear.

The lower guide device 322 is through a floor panel formed, which is angled relative to the plane of the paper feed is formed to the in the buffer device 320 entering paper web 308 from the plane of the paper feed deflect, which causes the formation of a loop becomes. The floor panel 322 has a plurality of recesses 372, by the air coming from the nozzles (Fig. 3, 326a and 326b) is delivered in the area between the bottom plate 322 and the paper web 308 is introduced. This additionally supports the formation of the loop 370 on the effect of the angled floor panel 322.

The upper guide device 324 serves to ensure that in the event that paper web 308 is due to of the blown air to the upper guide device 324 applies the paper web 308 through the upper guide device 324 safely to the paper delay device can be performed. The upper guide device includes a first guide plate 324a and a second guide plate 324b. The guide plates 324a, 324b each include a first section 374a, 374b, which under a Paper Feed Direction Angle (Arrow 376) are arranged. As indicated by arrows 378 is the angle at which the first sections 374a, 374b are arranged, adjustable. The guide plates also include 324a, 324b second sections 380a, 380b, respectively substantially parallel to the paper feed direction 376 extend and with the first sections 374a, 374b are connected. The guide plates 324a, 324b are on the second sections 380a, 380b of fasteners 382a, 382b attached. According to one embodiment are the fastening devices 382a, 382b as lockable Bearing designed to adjust the angle of the first Sections 374a, 374b. As can be seen in Fig. 4 is the second sections 380a, 380b of the guide plates 324a, 324b arranged to together with the floor panel 322 an input section 384 and an output section 386 of the buffer device 320.

As shown in FIG. 3, according to another embodiment the second guide plate 324b of the buffer device 320 on the one guide device 336a of the Paper delay device attached.

The cover 324c is that shown in FIG. 4 Embodiment on the second sections 380a, 380b the guide plates 324a, 324b attached. This will create a Air chamber 388 formed in the at high paper feed speeds occurring in the loop formation Vibrations are damped. The hood 324c also serves the sound absorption.

The buffer device 320 comprises - as in the first exemplary embodiment - A sensor device, by a light emitting Element 323a and a light receiving element 323b is formed. Element 323a is adjacent to the guide plate 324a and emits light in the direction of the guide plate 324b and on that arranged thereon Element 323b. The sensor device 140 determines the Height of the loop forming in the buffer device 320 370th

Due to the configuration of the buffer device described above 320 the behavior of the loop 370 becomes high Paper feed speeds, for example above of 0.8 m / s, reproducible again, so that no negative Influencing the cutting accuracy occurs. The tolerances the cutting accuracy can be maintained and there are no incorrectly cut sheets of paper on.

In the following, reference is again made to FIG. 3. The Paper delay device 306 includes a stamp member, that is held in a stamp member receptacle 330 is. The paper delay device 306 comprises also a counter stamp 332, the paper web 308 between passed the stamp 328 and the counter stamp 332 is. The stamp 328 is over the stamp member receiver 330 connected to a piston 334. The Piston 334 is guided in a guide device 336a, 336b. The piston 334 is biased by a spring 338 in such a way that that the spring force is effective to the punch 328th to be separated from the counter-stamp 332. The piston is on one End facing away from the stamp with a roller 340. The actuation of the stamp, i.e. whose movement against the Counter stamp 332 is made by means of a cam disc or Camshaft 342 communicating with roller 340. 'The camshaft 342 comprises a first part 342a which causes that the punch 328 pressed against the counter punch 332 is when the roller 340 with this area 342a in Connection is. Roll 340 is in a second Area 342b of the cam plate 342, so through the the spring 338 exerted spring force of the punch 328 by the Counter stamp 332 separated.

In other words, it means that the paper is delayed while the roller 340 is in the area 342a of the cam 342 is located, and that no delay on the paper is exercised while the roller 340 is in the area 342b of the cam plate 342.

Between the paper delay device 306 and the Cutting device 304, a guide device 344 is arranged, the one drive roller 346 and one guide roller 348, between which the paper web 308 is guided.

The guide roller 348 is against the drive roller by a spring 350 346 preloaded. The transport speed the guide device 344 is several times higher than the transport speed of the feed device 302. Thereby is achieved that during the deceleration process Accumulated loop until the next clamping cycle is removed again, the minimum height in the buffer device is not undercut.

The cutter 304 includes that shown in FIG Embodiment a drop knife 352 that between two guide devices 354, 356 is guided. The Knife 352 may be in the form of a guillotine knife be and is substantially perpendicular to the direction of paper travel arranged. Between knife 352 and one Counter-cutting edge 358, the paper web 308 to be cut is guided. The cutting machine 300 further includes a paper discharge device 360 in the paper feed direction after the Cutting device 304 is arranged. The paper discharge device 360 includes a drive roller 362 and a guide roller 364, between which the cut paper passed is. The roller 364 is countered by a spring 366 the drive roller biased. To ensure safe management of the cut paper from cutter 304 to the Ensuring paper discharge is a horizontal one Guide device 368 provided.

, It should be noted that the paper discharge device 360 removes the paper at a higher speed, than this by means of the feed device 302 is supplied. The speed of the paper guide devices 344, 360 are approximately the same size. This poses sure that the cut papers are safe from the cutter 300 can be removed.

The paper web 308 can be on or on, for example both sides by a printer device (not shown) be printed. The printer setup is located here with respect to the paper running direction in front of the paper feed device 302nd

The individual drive elements of the cutting device 300 by a control device (not shown in FIG. 3) controlled, this control device on the one hand ensures that the paper web in the feed phase is advanced by the desired cutting length, and then the cutting of the paper web is actuated. On the other hand the control device ensures that the in the buffer device Accumulated paper loop the minimum height not fall below by a suitable control of the corresponding drive elements. The sensor device detects a height h of the paper loop 370 (FIG. 4) in the buffer device 320 and gives a corresponding detection signal to the controller. The "height" of the loop is that Distance that it extends in one direction the perpendicular to a plane in which the paper web is fed and is cut is.

In the embodiment shown in FIG. 3, this is Knives 352 arranged in the cutting device 304, for example a drop knife. In the case of using a Fall knife, the paper delay device 306 is such controlled that the paper web 308 during cutting by the action of the stamp 328 on the paper web 308 is completely stopped.

According to an embodiment of the present invention can with respect to the paper feed direction in front of the paper feed device a so-called format recognition device is arranged be as it is known per se in specialist circles. This format recognition device controls the respective drives the paper feed device, the paper delay device and the paper cutter in such a way that cutting the paper web according to the predetermined Format.

Again, according to another embodiment, can be adjacent a detection device to the paper delay device be arranged, the predetermined marks captured on the paper web in order depending on the capture this marking the paper delay device and to control the cutting device in such a way that the paper web is cut according to the predetermined format.

The one located adjacent to the delay device Detection device can for example be a bptoelectronic Be converter of the appropriate markings can capture on the paper web.

According to a further exemplary embodiment, the cutting machine can comprise a cutting device which there as Rotary knife is executed. The rotary knife includes a roller to which a blade is attached. In one case can the blade at a fixed angular position of the roller be arranged and together with the shear bar an appropriate shape of the blade and the shear bar, as it is known per se in specialist circles, one Apply scissors to the paper web to be cut. This requires that the paper delay device the paper web completely during cutting stops.

A further embodiment of the rotary knife can be such be that the blade is not at a fixed angular position the roller is attached, but from a first Angular position extends continuously to a second angular position. It is also required that the paper delay device the paper web only to determine the Position where the cut is to be made, and then the further movement of the paper web with a Allows speed to match the speed of rotation the rotary knife is adjusted so that a Set the cutting edge that is perpendicular to the direction of the Paper web runs. The onward transport of the paper web from the paper delay device to the cutter takes place by means of the guiding device, which ensures that the speed described above is adjusted to to make the straight cut. A difference from the feeding speed of the paper web in the Cutting machine is compensated by the provided buffer.

Below are some performance parameters of a cutting machine, as described for example with reference to FIG. 3 was specified.

The cutting machine 300 described with reference to FIG. 3 has an output of 24,000 cuts per hour on, with dimensions of the resulting format of 304.8 x 210 mm. This corresponds to about 7 cuts per Second. The constant paper feed speed at such a cutting machine is 2.03 m / s.

Instead of the knife drives described above, the knife can the cutting device also by a continuous driven motor with subsequent switchable 1-speed clutch are driven.

It will be apparent to those skilled in the art that the present invention not on the exemplary embodiments described above is limited. In fact, it is also possible that 1 arrangement with that known from FIG. 3 Double element solution with regard to the delay device to realize the paper web. Likewise, in the case of FIG. 1 executed embodiment additionally a hood the buffer device 104 may be provided to the damping continue to improve. Likewise, the one shown in FIG Embodiment instead of the stamp a conveyor, as in the exemplary embodiment in FIG. 1 Is used.

Instead of the sensors described above, other Sensor arrangements familiar to experts for detecting the Loop height can be used. It is the same for professionals can be seen that the in the examples described above components used can be replaced as required can.

Claims (22)

1. Apparatus for cutting paper webs, comprising:

   a paper feeding means (102; 302);

   a cutting means (108; 304);

   a paper delay means (106; 306) which is arranged between the paper feeding means (102; 302) and the cutting means (108; 304) and delays the paper web (112; 308), which has been fed, in such a manner that a position where the cutting means (108; 304) cuts the paper web (112; 308) is determined on the paper web (112; 308);

   a buffer means (104; 320) arranged between the paper feeding means (102; 302) and the paper delay means (106; 306) so as to receive, during the delay of the paper web (112; 308), an accumulating length of the paper web (112; 308) in the form of a loop; and

   a control means (190),

   characterized in that
   the control means (190) controls the paper feeding means (102; 302) and the paper delay means (106; 306) such that the loop (195; 370) received in the buffer means (104; 320) does not fall short of a minimum height (h); and
   the paper delay means (106; 306) is a paper conveying means arranged between the buffer means (104; 320) and the cutting means (108; 304) and is controllable so as to stop or delay the paper web (112; 308).
2. Apparatus as claimed in claim 1, characterized in that
   the paper feeding means (102; 302) and the paper conveying means (106; 306) are arranged substantially in the same paper conveying plane.
3. Apparatus as claimed in claim 1 or 2, characterized in that
   in continuous operation, the control means (190) sets the pull-in speed such that a substantially constant speed of the fed paper web (112) is achieved.
4. Apparatus as claimed in any of claims 1 to 3, characterized in that
   the buffer means (104; 320) comprises a sensor (140; 323a, 323b) which detects the height (h) of the loop (195; 370) in the buffer means (104; 320), the control means (190) controlling the paper feeding means (102; 302) and the paper delay means (106; 306) depending on a detection signal of the sensor (140; 323a, 323b).
5. Apparatus as claimed in any of claims 1 to 4, characterized in that
   the control means (190) controls the paper feeding means (102; 302) and the paper delay means (106; 306) in such a manner that the loop (195; 370) received in the buffer means (104; 320) does not exceed a maximum height (h).
6. Apparatus as claimed in any of claims 1 to 5, characterized in that the paper conveying means is formed by a pair of drive rolls (160a, 160b).
7. Apparatus as claimed in any of claims 1 to 6, characterized by
   a fan means (134; 326a, 326b) which subjects the paper web (112; 308) in the area of the buffer means (104; 320) to an air flow so as to support the formation of the loop (195; 370) in the buffer means (104; 320).
8. Apparatus as claimed in claim 7, characterized in that
   the control means (190) controls the fan means (134; 326a, 326b).
9. Apparatus as claimed in any of claims 1 to 8, characterized in that
   the buffer means (104; 320) includes means for guiding (132, 136, 138; 322, 324a, 324b) the paper web (112; 308) accumulated.
10. Apparatus as claimed in claim 9, characterized in that
    the guiding means comprises a lower guiding means (132; 322) in the form of a lower plate, the lower plate including a plurality of recesses (132; 372).
11. Apparatus as claimed in claim 10, characterized in that
    the guiding means includes an upper guiding means having a first guiding plate (136; 124a) and a second guiding plate (138; 124b), each comprising a first portion arranged under an angle with respect to the paper feeding direction (110; 310), and each comprising a second portion arranged substantially in parallel with the paper guiding direction (110; 310), the angle at which the first portions are arranged being adjustable.
12. Apparatus as claimed in any of claims 1 to 11, characterized in that
    the buffer means (320) includes means for damping oscillations of the accumulated paper web (112; 308).
13. Apparatus as claimed in claim 12, characterized in that
    the damping means is formed by a hood (324c) enclosing the guiding means (322, 324a, 324b) and forming an air chamber.
14. Apparatus as claimed in any of claims 1 to 13, characterized in that
    the cutting means (108; 304) includes a falling knife arranged substantially perpendicularly to the paper web (112; 308) to be cut, or a rotary knife.
15. Apparatus as claimed in claim 14, characterized in that
    the paper delay means (106; 306) fully stops the paper web (112; 308).
16. Apparatus as claimed in any of claims 1 to 15, characterized in that
    the paper web (308) is provided with guiding perforations; and
    the paper feeding means (302) includes a tractor means (318a) for guiding the paper web (308).
17. Apparatus as claimed in any of claims 1 to 16, characterized by
    printer means arranged in the paper conveying direction upstream of the paper feeding means (102; 302) so as to print on the paper web (112; 308).
18. Apparatus as claimed in any of claims 1 to 17, characterized by
    a paper removal means (360) arranged in the paper conveying direction downstream of the cutting means (304) so as to pass on the individual papers which have been cut, respectively.
19. Apparatus as claimed in claim 18, characterized in that
    the paper removal means (360) removes the individual papers, which have been cut, at a higher speed than that at which the paper feeding means (302) feeds the paper web (308).
20. Apparatus as claimed in any of claims 1 to 19, characterized in that
    a format recognition means is arranged in the paper conveying direction upstream of the paper feeding means (102; 302), the format recognition means controlling the respective drives of the paper feeding means (102; 302), of the paper delay means (106; 306) and of the cutting means (108; 304) in such a manner that the paper web (112; 308) is cut in accordance with a predetermined format.
21. Apparatus as claimed in any of claims 1 to 19, characterized in that
    a detection means is arranged adjacent to the paper delay means (106; 306), the detection means detecting predetermined markings on the paper web (112; 308) so as to control the paper delay means (106; 306) and the cutting means (108; 304), depending on the detection of these markings, in such a manner that the paper web (112; 308) is cut in accordance with a predetermined format.
22. Apparatus as claimed in claim 21, characterized in that
    the detection means includes an optoelectronic means.

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