EP3077306B1 - Apparatus and method for cutting a web material into part-webs and spreading the part-webs - Google Patents

Description

The invention relates to a cutting and spreading device according to the preamble of claim 1.

The processing of sheet-like flat materials in the form of packaging films, in particular shrink films on packaging machines and especially on shrink packers is known. With the respective packaging film thereby products or product-filled packaging materials, such as. Bottles, cans, soft packs etc., but also packaged from such products or packaging. In a subsequent shrink tunnel of the packaging machine then shrinking the film takes place in such a way that this firmly attaches to the respective product or packaging and thereby a stable, salable package or container is obtained. Likewise, winding machines are known in which packaging or containers of packaging are wrapped in a packaging film.

The webs of sheet material used for packaging, for example packaging or shrink film, are usually provided in a web width which is greater than the web width required for further processing. It is therefore known to cut the original or conveyed web of flat material in a cutting and spreading device one or two times in the web longitudinal direction, so as to produce two or three single webs, having the required web width for packaging. In order to enable the processing of the single webs, it is also necessary to separate these single webs after cutting, i. to spread.

In known cutting and spreading devices, both the positionally accurate feed of the web material to be cut and the required spread of the partial webs obtained by the cutting in a Einrichtungsphase is set once, by aligning the web material supply relative to the cutting and spreading and / or by angular adjustment of used within the spreader, skewed Deflection rollers, such as in GB 2 239 965 A and EP 0 309 818 A2 shown. After a format change, for example, when using a new web material with a different width these adjustment and adjustment are carried out new. Due to dynamic processes during operation of the cutting and spreading device, deviations in the positional feed of the web material to the cutting device or within the spreading device can occur, which lead to fluctuating widths of the part webs or a positionally shifted feeding of the part webs to the following packaging station. This can lead to optically disturbing deviations or errors in the packaging of the containers, which can be recognized only on the finished packaged container. As a result, after a plant stop a reorientation of the web material or the spread must be made, which is time consuming and cost-causing.
Furthermore, in common cutting and spreading the part webs wider than necessary for the actual packaging process cut out of the web material to create in the transverse direction of the partial webs tolerance ranges that can be used in the subsequent packaging station to avoid packaging errors.

Proceeding from this, it is an object of the invention to provide a cutting and spreading device, which allows a precise cutting of the web material and subsequent spreading of the resulting partial webs. Furthermore, the film width should, for reasons of material savings, have as constant a minimum width as possible with which a secure packaging of the packaging material in the packaging station is possible. To solve this problem, a device according to the patent claim 1 is provided.
The invention initially relates to a device for cutting a web material into a plurality of sub-webs by longitudinal cutting and spreading of the sub-webs. The device comprises a dispensing device for providing the web material, at least one cutting device for generating at least one longitudinal section in the web material and at least one spreading device, by means of which the partial webs obtained after the at least one longitudinal section are deflected at least partially transversely to their conveying direction and spaced apart by the deflection. Furthermore, a first Provided control loop, by means of which the position of the web material is controlled transversely to the conveying direction before being fed to the cutting device. Furthermore, a second, cooperating with the spreading device control circuit is provided by means of which a control of the deflection of at least one sub-web takes place transversely to its conveying direction. This spreading device includes two separate, separately operating control loops for the left and right outer sub-web.
In particular, a supply of the web material to the cutting device in a desired position is achieved by the first control loop. This ensures that the longitudinal cuts are made at a predetermined position in the web material and thus partial webs of a desired width are obtained. The width of the individual partial webs can be chosen absolutely and relative to each other as desired. Preferably, a central feed of the web material to the cutting device is achieved by the first control loop. This central feed is particularly advantageous for the production of partial webs with the same widths.

By means of the second control circuits, the spreading of the partial webs is achieved to a desired desired spread, i. the respective partial webs leave the spreading device with a defined distance relative to each other. In particular, a change in position of the respective partial webs is achieved within the spreader such that the opposing longitudinal edges of two juxtaposed partial webs to each other have a defined distance. The juxtaposed partial webs leave the spreading device preferably parallel to one another and in a common conveying plane.

The implementation of the first and second control circuits ensures that partial webs of a defined width and in a predetermined spread are permanently provided by means of the device according to the invention, so that in the subsequent packaging station the packaging of packaging can be made into containers of high, consistent quality. Furthermore, the widths of the partial webs can be reduced by the control according to the invention due to lower required tolerance limits, which leads to a significant material savings in the web material used.

According to a further embodiment, the first control circuit comprises at least one sensor unit for detecting the position of the web material transversely to its conveying direction, a control unit and an actuator, by means of which the position of the web material is changeable transversely to its conveying direction. Preferably, a pair of sensor units may also be provided on opposite sides of the web material. About this at least one sensor unit, a measurement signal can be obtained which indicates the position of the web material relative to the sensor unit and thus relative to the cutting device. The sensor unit is preferably coupled to the control unit, which receives the measurement signal and generates a control signal on the basis of this measurement signal. Based on this control signal, the control of the actuator, which causes a change in the feed position of the web material by acting on a Bahnjustiereinrichtung.

According to a further embodiment, the second control circuit comprises at least one sensor unit for detecting the position of a partial web transversely to the conveying direction, a control unit and an actuator, which cooperates with the spreading device and influenced by this interaction, the amount of deflection of the partial web transverse to its conveying direction. Via the sensor unit of the second control circuit, a further measurement signal can be obtained, which indicates the position of the respective partial path relative to the sensor unit. On the basis of this measurement signal, the distance can be determined, which have two side webs arranged side by side to each other. The sensor unit is preferably coupled to the control unit, which receives the measurement signal and determines the distance of the sub-paths arranged side by side on the basis of this measurement signal. This determined actual distance is compared by means of the control unit with a desired distance. Furthermore, a control signal is generated, which depends on the deviation of the actual distance from the desired distance. Based on this control signal, the control of the actuator, which causes a change in the spread of the partial webs by acting on an adjustment mechanism in the spreading.

According to a further embodiment, the first control circuit cooperates with the dispensing device and is for displacing the dispensing device relative to the cutting device transversely to the conveying direction of the web material or a rotation of the dispensing device relative to the cutting device formed around a perpendicular to the conveying direction vertical axis. For example, the dispensing device is arranged on a slide which can be displaced linearly in the transverse direction, on which the actuator of the first control loop acts and effects the displacement of the dispensing device. Alternatively, the dispensing device can be arranged on a rotating about a vertical vertical axis of rotation frame on which the actuator of the first control circuit acts and thus causes a rotation of the dispensing device. The change in position of the dispensing device can cause a change in the feed position relative to the cutting device.

A particular advantage of the aforementioned, displaceable dispensing device is that it can be easily retrofitted in existing packaging machines.

According to a further embodiment, the first control loop cooperates with a path adjusting device provided between the dispensing device and the cutting device, which is designed to effect a displacement of the web material transversely to its conveying direction by turning and / or displacement. The web alignment device may in particular contain a plurality of rollers by means of which the web material is deflected several times. The web alignment device may, in particular, comprise a rotary frame which is rotatable about a vertical axis, in particular a vertical vertical axis, in order to effect a positional change. Particularly preferably, the web alignment device can have a first deflecting roller at the inlet, a second deflecting roller at the outlet and between these deflecting rollers a pair of rollers held on the revolving frame. The pair of rollers is preferably arranged vertically offset from the plane spanned by the first and second deflection roller. By rotation of the rotating frame, the orientation of the axes of rotation of the roller pair relative to the axes of rotation of the first and second guide roller can be changed, which leads to the change in position of the web material in the transverse direction. The main advantage of the provision of a Bahnjustiereinrichtung in the conveying path of the web material between the dispensing device and the cutting device is that even existing systems can be retrofitted by inserting the Bahnjustiereinrichtung with little effort.

According to a further embodiment, the spreading device has a plurality of pairs of rollers associated with the individual sub-webs, wherein the axes of rotation of the pairs of rollers are at least partially changeable by inclinations in their orientation. Preferably, the axes of rotation of the rollers of a pair of rollers are changed uniformly in magnitude and direction. Due to the inclination of the axes of rotation of the roller pairs, a change in position of the subsidized by the pair of rollers sub-web and thus a change in the distance of this sub-web can be achieved to adjacent sub-webs.

According to a further embodiment, the angular position of the axes of rotation of a pair of rollers in the same direction by means of an adjusting mechanism is changeable. The adjustment mechanism may, for example, have a slidably held receptacle, in each of which a bearing point of the two rollers of the roller pair is held. By the displacement of the recording can thus the angular position of the axes of rotation of the rollers of the pair of rollers amount and direction are changed.

According to a further embodiment, the actuator of the second control circuit acts on the adjusting mechanism of the spreading device. This can be achieved by the second control loop an adjustment of the spreading caused by the spreading.

According to a further embodiment, the sensor unit of the first control loop is designed to detect a longitudinal edge of the web material and / or a pair of mutually opposite sensor units for simultaneous detection of both longitudinal edges of the web material is provided. The detection of the longitudinal edges of the web material is advantageous because they are easily detectable, for example by ultrasonic sensors. Furthermore, upon detection of the longitudinal edges of the web material reference marks for determining the position of the web material relative to the cutting device can be dispensed with.

According to a further embodiment, the sensor unit of the second control loop is designed to detect a longitudinal edge of a partial web, which was laterally deflected by the spreading device. The detection of the longitudinal edges of the partial web is advantageous because they are also easily detectable are, for example by ultrasonic sensors. Furthermore, reference markings for determining the spread can be dispensed with when the longitudinal edges of the partial web are detected.

According to a further embodiment, a plurality of second control circuits are each provided with at least one sensor unit and an actuator, wherein the individual sensor units are each assigned to different sub-webs and wherein each sensor unit is designed to detect a longitudinal edge of its associated, laterally deflected by the spreader sub-web. This allows the spread of all determined by the spreader in their position sub-webs determined.

According to a further embodiment, the sensor units are at least partially formed by ultrasonic sensors. Ultrasonic sensors can be used with any soundproof material such as plastic, paper or metal. Ultrasonic sensors allow the edges to be determined even from transparent sheet materials. In addition, ultrasonic sensors are insensitive to dirt and thus have a high detection reliability.

According to a further embodiment, the sensor units are at least partially forked or U-shaped and have two opposing legs. Thus, the sensor unit can be arranged such that the sensor unit surrounds the web material or the partial web.

According to a further exemplary embodiment, a first leg of the sensor unit has a transmitter for emitting a measuring signal and a second leg of the sensor unit has a receiver which is designed to receive the measuring signal. Thus, a lying between the transmitter and the receiver longitudinal edge of the web material or the sub-web can be optimally recognized. Preferably, the transmitter is an ultrasonic transmitter and the receiver is an ultrasonic receiver.

According to the invention, the spreading device has means for compensating for the path difference between partial webs which travel through paths of different lengths relative to one another. There is one
provided third control circuit, which cooperates with the means for compensating the path difference and controls these means such that the partial webs at least partially pass through equally long distances within the spreader. The means for compensating the path difference can be formed, for example, by at least one displaceable roller. By the means for compensating the path difference between partial webs it is achieved that the partial webs, regardless of the degree of change in position, which have experienced the respective partial web within the spreader, leave the spreader without a longitudinal offset.

According to a further embodiment, the third control circuit has at least two sensor unit and a control unit for detecting a path difference between two partial paths with different deflection and an actuator which, depending on the determined path difference, drives the means for compensating the path difference. The sensor units can be assigned to different partial webs and designed to detect reference marks on the partial webs. Thus, based on the measurement signals obtained by the sensor units by the control unit, a longitudinal offset of the partial webs relative to one another can be determined. The control unit is preferably designed to provide a control signal, which is transmitted to the actuator. This actuator is in operative connection with the means for compensating the path difference or the longitudinal offset in order to eliminate this by the controlled action.
According to a further embodiment, the sensor units are adjustable by motor transversely to the conveying direction of the web material or the partial webs. In particular, the adjustability is controlled by a central control unit, for example a control unit controlling the entire machine. As a result, the sensors can be moved to the required nominal positions depending on the format of the processed web material or the required spread. This achieves a simplified changeover during format changes.

Fig. 1

beispielhaft in einer Drauf- und Seitenansicht eine erfindungsgemäße Vorrichtung zum Schneiden und Spreizen von Bahnmaterial in einem ersten Ausführungsbeispiel;

Fig. 2

beispielhaft in einer Drauf- und Seitenansicht eine erfindungsgemäße Vorrichtung zum Schneiden und Spreizen von Bahnmaterial in einem zweiten Ausführungsbeispiel;

Fig. 3

beispielhaft in einer Drauf- und Seitenansicht eine erfindungsgemäße Vorrichtung zum Schneiden und Spreizen von Bahnmaterial in einem dritten Ausführungsbeispiel;

Fig. 4 - 7

beispielhaft Darstellungen zur Einrichtung einer Vorrichtung zum Schneiden und Spreizen von Bahnmaterial gemäß dem zweiten Ausführungsbeispiel aus Fig. 2;

In the context of the invention, web materials are understood in particular to be plastic films, paper, metal or textile webs or other materials provided in web form. The sheet materials may be provided in particular in roll form.
Actuator in the sense of the invention, in particular motor drives, such as linear drives or rotary drives, etc. understood.
Sensor units in the sense of the invention are understood to mean any sensors, in particular ultrasonic sensors, infrared sensors, color line sensors, photosensitive sensors, or also CCD sensors (CCD: charge-coupled device).
Further developments, advantages and applications of the invention will become apparent from the following description of exemplary embodiments and from the figures.
The invention will be explained in more detail below with reference to the figures of several embodiments. Show it:

Fig. 1

by way of example in a top and side view of an apparatus according to the invention for cutting and spreading of web material in a first embodiment;

Fig. 2

by way of example in a top and side view of an apparatus according to the invention for cutting and spreading of web material in a second embodiment;

Fig. 3

by way of example in a top and side view of an apparatus according to the invention for cutting and spreading of web material in a third embodiment;

Fig. 4-7

Illustrative representations for the establishment of an apparatus for cutting and spreading of web material according to the second embodiment Fig. 2 ;

In the FIGS. 1 to 3 is shown in plan and side view of an inventive cutting and spreading device 1 in different embodiments. The cutting and spreading device 1 will be described below with the aid of a three-dimensional Cartesian coordinate system with x-y and z-axis. The device comprises a dispensing device 2, by means of which the web material 10 to be processed is provided. The dispensing device 2 may in particular comprise a device for holding a supply of the web material 10, in particular a mandrel for receiving a roll of the web material. Furthermore, the dispensing device 2 can also comprise a plurality of such devices for holding a supply of the web material 10 and a connecting device 2.1, for example a splicing device. By means of this connecting device 2.1, after the consumption of a first supply 2.2 of the web material 10, the end of this web material can be connected to the beginning of the web material provided by the second supply 2.2 '. This can be done without interruptions of the overall system a change of the web material supply. In particular, the web material 10 may be provided in roll form, wherein the web material 10 is obtained from the web material supply by unwinding.

The web material 10 passes in the conveying direction FR, which runs parallel to the x-axis, following first a cutting device 3, which is designed to introduce longitudinal sections into the web material 10. The cutting device 3 may in this case in particular contain cutting blades which are engaged by engagement in the web material 10 effect longitudinal cuts, thereby separating the web material 10 into a plurality of sub-webs 10a, 10b, 10c. The web material 10 has, in particular, a longitudinal direction LR extending in the conveying direction FR (negative x direction) and a transverse direction QR (y direction) running perpendicular to the longitudinal direction LR, ie the web material 10 extends with its broad side in the y direction. The web material 10 has a width b in the transverse direction QR. By the cutting device 3, the web material 10 is cut at least once, preferably at least twice in the longitudinal direction LR. This results in the partial webs 10a, 10b, 10c, which have a reduced width with respect to the web material 10. Preferably, the web material 10 is cut by the cutting device 3 into a plurality of equally wide partial webs 10a, 10b, 10c. Deviating from this, however, it is also possible that the partial webs 10a, 10b, 10c have different widths.

Following in the conveying direction FR on the cutting device 3, the partial webs 10a, 10b, 10c then pass through a spreading device 4, by means of which the partial webs 10a, 10b, 10c in the transverse direction QR, i. spread in the y direction, i. spaced apart from each other. In the embodiment shown, the cutting device 3 and the spreader 4 are combined as a cutting spreader, i. the cutter 3 and the spreader 4 are formed by a common device component. Alternatively, the cutting device 3 and the spreading device 4 can also be formed by different, separate device components. Subsequently, the spaced partial webs 10a, 10b, 10c are guided parallel to each other by a dancer shaft means 6 having a plurality of dancer waves parallel to each other and then fed to a packaging station, not shown. The web material 10 may be, for example, a plastic film web. The packaging station can be formed, for example, by a film winding station or a film shrinking station.

The cutting and spreading device 1 has a plurality of control circuits 20, 30, by means of which during operation of the cutting and spreading device 1 dynamically both the positional supply of the web material 10 to the cutting device 3 and the spreading, ie the spacing of the partial webs 10a, 10b, 10c are mutually controllable. In particular, a first control loop 20 is provided, by means of which the feeding of the web material 10 to Cutting device 3 in the transverse direction QR, that is controllable in the y-direction. The first control circuit 20 comprises at least one sensor unit 21, 21 ', which is connected to a control unit 22 in order to transmit a measurement signal detected by the sensor unit 21, 21' to the control unit 22. Furthermore, the first control circuit 20 additionally comprises an actuator 23, which is actuated by a control signal provided by the control device 22 and is mechanically connected to a web alignment device 5 for changing the feed position or feed position of the web material 10, so that by acting on the actuator 23 Bahnjustiereinrichtung 5 feeding the web material 10 to the cutting device 3 in the transverse direction QR, ie in the y direction can be influenced.

The at least one sensor unit 21, 21 'is provided for example between the dispensing device 2 and the cutting device 3 and designed to detect the actual position of the web material 10 in the y direction. The sensor unit 21, 21 'may be, in particular, a sensor which detects the longitudinal edge of the web material 10, ie an edge running in the conveying direction FR. In particular, the sensor unit 21, 21 'U-shaped with two spaced-apart sensor legs and for embracing the longitudinal edge of the web material 10 may be formed. In this case, a first sensor leg above the web material 10 and a second sensor leg opposite the first sensor leg may be provided underneath the web material 10. The first sensor leg can in this case have a transmitting element emitting a measuring signal and the second sensor leg can have a receiving element receiving this measuring signal. Preferably, the sensor unit 21, 21 'can be formed by an ultrasonic sensor. Alternatively, other types of sensors, such as infrared sensors, color line sensors, photosensitive sensors, or CCD sensors (CCD: Charge-Coupled Device) can be used. Furthermore, in order to detect the position of the web material 10 in the transverse direction QR (y direction), a pair of sensor units 21, 21 'may also be used, wherein the sensor units 21, 21' are preferably arranged opposite one another at different longitudinal edges of the web material 10. As a result, not only the absolute position of these longitudinal edges but also the width b of the web material 10 can be continuously determined by this sensor unit pair at the same time.

An actual position or an actual position of the web material 10 in the y direction is determined by the at least one sensor unit 21, 21 'and transmitted to the control unit 22 as a measurement signal. The control unit 22 compares the received actual position or an actual position of the web material 10 with a desired position. This desired position is either stored in the control unit 22 or the control unit 22 has access to an external memory area in which this desired position is stored. Alternatively, the desired position can also be provided by a central control unit 50, for example a machine control system controlling the entire packaging station. Based on the actual position and the desired position, the control unit 22 determines a control signal, which is transmitted to the actuator 23. The actuator 23 cooperates with the web alignment device 5, by means of which the feed position of the web material in the y-direction is variable. Depending on the control signal, the actuator thus adjusts the feed position of the web material 10 to the cutting device 3 in order to minimize the deviation of the actual position from the desired position. As a result of this dynamic control during the ongoing processing of the web material 10, the positionally correct feeding of this web material 10 to the cutting device 3 in the y-direction can thus be ensured, i. Ideally, the web material 10 is fed in the desired position of the cutting device 3.

As in FIG. 1 shown, the Bahnjustiereinrichtung 5 may be associated with the dispensing device 2 or be part of this dispensing device 2. Thus, for example, the web stock 2.2, for example, a winding mandrel, on which the web material is arranged, be arranged on a carriage which is actuated by the actuator displaced in the y-direction. Alternatively, it is also possible to make the entire dispensing device 2 displaceable in the y-direction. This dispensing device 2 may for example contain a plurality of web material stores 2.2, 2.2 ', guide means for the web material 10, in particular guide rollers and / or the connecting device 2.1.

FIG. 2 shows a further alternative of a Bahnjustiereinrichtung 5, namely with a rotating frame 8. In this case, that of the dispensing device 2, which in the embodiment according to FIG. 2 is formed stationary, provided web material 10 via a first guide roller 8.1, an offset from the first guide roller 8.1 arranged roller pair 8.2 and a second, in turn offset to the pair of rollers 8.2 arranged deflecting 8.3 led to the cutting device 3. Preferably, the axes of rotation of the first and second guide rollers 8.1, 8.3 clamp a first plane which is parallel to a second plane which is spanned by the axes of rotation of the roller pair 8.2. The rollers of the roller pair 8.2 are coupled to change the feed position of the strip material 10 to the cutting device 3 via the rotary frame 8, which is rotatable about a vertical, extending in the z-direction, ie perpendicular to the conveying direction FR and the transverse direction QR extending vertical axis HA. As a result of the rotation of the rotary frame 8, the feed position of the strip material 10 is changed as a function of the direction of rotation, that is, the web material 10 is displaced in the positive or negative y direction.

The first control circuit 20 associated, at least one sensor unit 21, 21 'is arranged in the embodiment shown between the pair of rollers 8.2 and the second guide roller 8.3. Alternatively, it is also possible to provide the sensor unit 21, 21 'between the second deflecting roller 8.3 and the cutting device 3. The control of the feed position of the web material 10 to the cutting device 3 is equivalent to the embodiment described above FIG. 1 , wherein the actuator 23 in the embodiment according to FIG. 2 acting on the rotating frame 8 and thereby causes its rotation about the vertical axis HA in response to the control signal.

The aim of the first control loop 20 is to feed the web material 10 in relation to its orientation in the transverse direction QR in the correct position of the cutting device 3, in order to obtain a desired partial web width in the part webs 10a, 10b, 10c formed by cutting. The cutter 3 has cutting blades for obtaining N partial webs 10a, 10b, 10c (N-1), where N is a natural number.

The cutting device 3 and the following spreading device 4 following in the conveying direction FR are preferably designed as a combined cutting-spreading device, as described in the patent application German patent application DE 10 2009 008 936 A1 The disclosure of this patent application is incorporated in its entirety in the disclosure of this application. In particular, the partial webs 10a, 10b, 10c obtained after cutting are distributed over different roller pairs of the spreader 4 guided. The spreader 4 includes in particular a plurality of pairs of rollers 4.1, 4.2, 4.3, which are each assigned to a part web 10a, 10b, 10c to be processed and by which the respective part webs 10a, 10b, 10c are deflected several times. The rollers are at least partially accommodated in such a way in the spreading device 4, that the axis of rotation is pivotable, namely pivotable within the xy plane. As a result of this pivotability of the axes of rotation of the rollers, during the deflection of the respective partial web 10a, 10b, 10c, a change in position of the partial web 10a, 10b, 10c in the y-direction and thus a spreading of the partial webs 10a, 10b, 10c relative to one another can be achieved. In particular, the pivotability of the axes of rotation of belonging to a pair of rollers 4.1, 4.2, 4.3 rollers selected such that they are swivel in terms of magnitude and direction. The number of roller pairs in the spreader 4 corresponds to the number of sub-webs 10a, 10b, 10c to be processed.

In order to obtain the spreading of the partial webs 10a, 10b, 10c, the rolls of that pair of rolls around which the partial web to be laterally displaced in the transverse direction QR is inclined, are inclined so that the axis of rotation of the roll encloses an acute angle with the Y axis , The change in position of the respective partial web 10a, 10b, 10c by deflection at the inclined rollers of its associated pair of rollers depends directly on the angular amount by which the rollers of the pair of rollers were tilted. This allows the change in position of a partial web 10a, 10b, 10c and thus the spread of these partial webs to each other directly by the inclination of the rollers of the respective pairs of rollers 4.1, 4.3 influence.

In the in FIGS. 1 to 3 In the embodiments shown, the cutting device 2 has two cutting blades, so that three partial webs 10a, 10b, 10c are obtained from the web material 10 by the cutting device 2. It is understood that this design is chosen arbitrarily and the cutting and spreading device 1 according to the invention can contain any number of cutting blades in the cutting device 2 and thus can process any number of partial webs. In the event that an odd number of partial webs 10a, 10b, 10c is processed, preferably the position of the middle partial web 10b remains unchanged, ie the middle partial web 10b is associated with a pair of rollers in which the axes of rotation of Rolls run exactly perpendicular to the conveying direction FR. All other partial webs, ie in the embodiment shown, the partial webs 10a and 10c, which are to experience a change in position in the transverse direction QR by the spreader 4, a second control circuit 30 is associated with at least one sensor unit 31, a control unit 32 and an actuator 33. As a result, the positional changes of the individual partial webs 10a, 10c can be controlled independently of one another.

The sensor unit 31 is, as already described above with respect to the sensor unit 21, preferably designed to detect a longitudinal edge of its associated sub-web 10a, 10c. For this purpose, in turn, a U-shaped sensor unit 31 may be used, which is preferably an ultrasonic sensor. By means of the at least one sensor unit 31, an actual position or an actual position of the partial track 10 a, 10 c assigned to the sensor unit 31 is determined with respect to the y-direction and transmitted as a measuring signal to the control unit 32. The control unit 32 compares the received actual position or an actual position of the partial web 10a, 10c with a desired position. This desired position is either stored in the control unit 32 or the control unit 32 has access to an external memory area in which this desired position is stored. Alternatively, the desired position can also be provided by the central control unit 50, for example a machine control system controlling the entire packaging station. Based on the actual position and the desired position, the control unit 32 determines a control signal, which is transmitted to the actuator 33. The actuator 33 cooperates with an adjusting mechanism of the spreading device 4, by means of which the inclination of the respective sub-path deflecting roller pair 4.1, 4.2, 4.3 is variable. Depending on the control signal is carried out by the actuator 33 thus an adjustment of the inclination of the rollers of the respective pair of rollers and thus a change in position of the subsidized by the rollers part web 10a, 10c, thereby minimizing the deviation of the actual position of the desired position. By this dynamic control during the ongoing processing of the web material 10 so that the correct position forwarding of the partial webs 10a, 10b, 10c can be ensured to the packaging station.

Preferably, when processing an even number of partial webs, each partial web and when processing an odd number of partial webs are all Part tracks except the middle part of a track 30 associated with a second loop. The control units 32 of these second control circuits 30 can be formed at least partially by a single control unit 32.

Depending on the number of processed by the spreader 4 partial webs 10 a, 10 b, 10 c and depending on the degree of spreading can be traversed by the change in position in the transverse direction QR the sub-webs 10 a, 10 b, 10 c within the spreader 4 different path lengths, so that a longitudinal offset Δl between the partial webs 10a, 10b, 10c can occur. To compensate for this longitudinal offset .DELTA.l, a third control circuit 40 is provided which comprises at least two sensor units 41, 41 ', a control unit 42 and an actuator 43. The two sensor units 41, 41 'are in this case assigned to different partial webs 10a, 10b, so that the longitudinal offset Δl can be determined by the sensor units 41, 41'.

The sensor units 41, 41 'are preferably designed for the detection of reference marks, which are formed for example by suitable locations on the printed image of the partial webs 10a, 10b, 10c or by specially provided for this purpose print marks. Before cutting the web material 10 into the part webs 10a, 10b, 10c, these reference marks form a line transverse to the conveying direction FR, i. the reference marks come to lie on a line parallel to the y-axis. Thus, the offset of the reference marks to each other corresponds to the longitudinal offset .DELTA.l.

The sensor units 41, 41 'are connected to the control unit 42 for transmitting the measurement signals provided by the respective sensor units 41, 41'. The magnitude determination of the longitudinal offset .DELTA.l can be determined from the time offset, the reference marks are detected by the sensor units 41, 41 'and the conveying speed of the web material 10. Depending on the time offset with which the reference marks are detected by the respective sensor units 41, 41 ', a control or control signal is generated by the control unit 42, by means of which the actuator 43 is controlled.

The actuator 43 is operatively connected to a Weglängenverstellmechanik the spreader 4, which is controlled by the actuator 43, the path length, the one of the two partial webs, which were used for longitudinal displacement measurement, passes through, changed in such a way that the longitudinal offset .DELTA.l is eliminated. The Weglängenverstellmechanik can be formed, for example, to change the distance between rollers of a pair of rollers, which deflects the respective partial web. Preferably, in the embodiment shown, the Weglängenverstellmechanik acts on the central part of web 10b, so that at the same spread of the three partial webs 10a, 10b, 10c at the same time the Längsversatze .DELTA.l between the two partial web pairs (middle partial web to the respective outer partial webs) are resolved.

Preferably, the sensor units 21, 21 ', 31, 41, 41' slidably, in particular motor-displaced relative to the web material 10 and the partial webs 10a, 10b, 10c may be arranged. The sensor units 21, 21 ', 31, 41, 41' can be used in particular in the transverse direction QR, i. be slidably provided in a direction parallel to the y-direction. Each sensor unit 21, 21 ', 31, 41, 41' is preferably assigned a respective drive 9, via which an adjustment of the sensor units 21, 21 ', 31, 41, 41' takes place in the transverse direction QR. By means of the respective drives 9, the sensor units 21, 21 ', 31, 41, 41' can be transversely to the conveying direction FR of the web material as a function of the width b of the web material 10 and the spreading of the part webs 10a, 10b, 10c caused by the spreading device 4 10 to the desired position. The drives 9 can in this case in particular be connected to the central control unit 50, which effects, for example, the overall control of the cutting and spreading device 1, so that the sensor units 21, 21 ', 31, 41, 41' controlled by the central control unit 50 are dependent on predetermined parameters, for example, the width of the web material 10 or the spreading to be effected in a defined desired position procedure.

The embodiment according to FIG. 3 corresponds essentially to the previously described embodiments according to FIGS. 1 and 2 , where the in FIG. 3 cutting and spreading device 1 shown only the first control circuit 20 for positionally accurate feeding of the web material 10 to the cutting device 3 and the second control circuit 30 for controlling the spreading of the partial webs 10a, 10b, 10c. In this embodiment, which is designed in particular for processing a fixed format of a web material, the dynamic control caused by the third control loop 40 is dynamic Longitudinal displacement control replaced by a manually adjustable and fixed for the format to be processed Weglängenverstellmechanik. Furthermore, in this embodiment, a motor displacement of the sensor units 21, 21 ', 31 due to the use of a fixed format of the web material 10 is omitted.

The following is based on the FIGS. 4 to 7 the commissioning of the cutting and spreading device 1 or the new device with a web material 10 to be cut and spread is described. First, the web material 10 is threaded through the spreader 2 via the web adjusting device 5, the cutter 3, the spreader 4, and the dancer shaft device 6 formed by the rotating frame 8. The cutting blades of the cutting device 3 are not engaged with the web material 10. In the spreader 4, the strip material is guided over the adjustable in their angular adjustment roller pairs 4.1, 4.3. The sensor units 21, 21 ', 31, 41, 41' are positioned outside of their working range by the higher-order control unit 50.

As in FIG. 5 The cutting blades 3.1 of the cutting device are subsequently brought into engagement with the web material 10 so that it is separated into the part webs 10a, 10b, 10c. In addition, the sensor units 21, 21 ', 31, 41, 41' are moved by the central control unit 50 to its desired position. Subsequently, as in FIG. 6 shown by the dashed line, the middle part of the web 10b severed in the transverse direction QR, passed over the pair of rollers 4.2 and the part of the web ends obtained by cutting again connected to each other.

The following will, as in FIG. 7 represented by the central control unit 50 causes the spreading of the spreading device 4 by tilting the roller pairs 4.1, 4.3 set to a desired target spread. Here, the tilting of the rollers of the roller pairs 4.1, 4.3 causing actuator 33 can be controlled by the central control unit 50. After setting the desired spread, the longitudinal edges of the partial webs 10a, 10c come to lie within the detection range of the sensor units 31, 31 '. Alternatively, with a motorized adjustment of the sensor units 31, 31 ', it is possible for the method of the sensor units 31, 31' to be in their respective desired position and to set the spread to the desired spread takes place simultaneously. After completion of these steps, the continuous registration of the web material 10 to the cutting device by the first control circuit 20, the regulation of the spreading of the partial webs 10a, 10b, 10c by the second control circuit 30 and. With continuous conveying of the web material 10 by the cutting and spreading if necessary, the regulation of the longitudinal offset .DELTA.l by the third control circuit 40 begin.

LIST OF REFERENCE NUMBERS

1

Cutting and spreading device

2

dispenser

2.1

splicing

2.2, 2.2 '

Sheet stock

3

cutter

3.1

cutting blade

4

spreading

4.1 - 4.3

roller pair

5

Bahnjustiereinrichtung

6

Dancers wave device

8th

rotating frame

8.1

first deflecting roller

8.2

roller pair

8.3

second guide roller

9

drive

10

sheeting

20

first control loop

21, 21 '

sensor unit

22

control unit

23

actuator

30

second control loop

31

sensor unit

32

control unit

33

actuator

40

third control loop

41, 41 '

sensor unit

42

control unit

43

actuator

50

central control unit

b

width

FR

conveying direction

HA

vertical axis

LR

longitudinal direction

QR

transversely

.DELTA.l

longitudinal offset

Claims (15)

1. Apparatus for cutting a web material (10) into a number of part-webs by longitudinally cutting and spreading the part-webs, comprising a dispensing device (2) for providing the web material, at least one cutting device (3) configured to create at least one longitudinal cut in the web material, and at least one spreading device (4) by means of which the part-webs (10,10b,10c) obtained following the at least one longitudinal cut are deflected at least in part transversely to the conveying direction (FR) thereof, and are spaced apart from one another by the deflection, wherein provision is made for a first control circuit (20) by means of which the position of the web material (10) transversely to the conveying direction (FR) thereof is controlled prior to feeding to the cutting device (3), and that provision is made of at least one second control circuit (30) which interacts with the spreading device (3) and by means of which the deflection of at least two part-webs (10a,10c) transversely to the conveying direction (FR) thereof is controlled, and wherein the first control circuit (20) comprises at least one sensor unit (21, 21') for detecting the position of the web material (10) transversely to the conveying direction (FR) thereof, a control unit (22), and an actuator (23), by means of which the position of the web material transversely to the conveying direction (FR) thereof can be changed, wherein
   the second control circuit (30) comprises at least one sensor unit (31) for detecting the position of a part-web (10a, 10c) transversely to the conveying direction (FR) thereof, at least one control unit (32), and at least one actuator (33), which interacts with the spreading device (4), and, by way of this interaction, influences the amount of the deflection of the part-web (10a, 10c) transversely to the conveying direction (FR) thereof, characterised in that
   the spreading device (4) comprises means for compensating for the path difference between part-webs (10a, 10b, 10c), which run through path stretches which are of different lengths relative to one another, and that a third control circuit (40) is provided, which interacts with the means for compensating for the path difference, and which actuates these means in such a way that the part-webs (10a, 10b, 10c) run at least partially through path stretches of equal length, and
   wherein, by means of the one control arrangement for the deflection of the at least two part-webs (10a, 10c) transversely to the conveying direction (FR) thereof, the deflection of the two outer part-webs (10a, 10c) takes place, wherein no such control arrangement is provided for the part-web (10b) arranged between them.
2. Apparatus according to claim 1, characterised in that the third control circuit (40) comprises at least two sensor units (41, 41') and a control unit (42) for detecting a path difference between two part-webs (10b, 10c) with different deflection, and an actuator (43), which actuates the means for compensating the path difference depending on the path difference which is detected.
3. Apparatus according to claim 2, characterised in that the sensor units are allocated to different part-webs and are configured for the detection of reference marks on the respective part-webs.
4. Apparatus according to any one of the preceding claims, characterised in that the first control circuit (20) interacts with the dispensing device (2), and is configured so as to displace the dispensing device (2) relative to the cutting device (3) transversely to the conveying direction (FR) of the web material (10), or to incur a rotation of the dispensing device (2) relative to the cutting device (3) about a vertical axis running perpendicular to the conveying direction (FR).
5. Apparatus according to any one of the preceding claims, characterised in that the first control circuit (20) interacts with a web adjustment device (5), which is provided between the dispensing device (2) and the cutting device (3), which is configured such as to effect a displacement of the web material (10) transversely to the conveying direction (FR) thereof, by rotation and/or by displacement.
6. Apparatus according to any one of the preceding claims, characterised in that the spreading device (4) comprises a plurality of roller pairs, allocated to the individual part-webs (10a,10b,10c), wherein the rotation axles of the roller pairs can be at least partially changed by oblique sections in their alignment.
7. Apparatus according to claim 6, characterised in that the angled sections of the rotation axles of a roller pair can be changed in the same direction by means of an adjustment mechanism.
8. Apparatus according to claim 7, characterised in that the actuator (33) of the second control circuit (30) takes effect on the adjustment mechanism of the spreading device (4).
9. Apparatus according to any one of the preceding claims, characterised in that the sensor unit (21, 21') of the first control circuit (20) is configured so as to detect a longitudinal edge of the web material (10) and/or that a pair of mutually opposed sensor units (21, 21') are provided for the simultaneous detection of both longitudinal edges of the web material (10).
10. Apparatus according to any one of the preceding claims, characterised in that the sensor unit (31) of the second control circuit (30) is configured for the detection of a longitudinal edge of a part-web (10a, 10c), which was deflected laterally by the spreading device (4).
11. Apparatus according to any one of the preceding claims, characterised in that a plurality of second control circuits (30) are provided in each case with at least one sensor unit (31) and an actuator (33), that the individual sensor units (31) are allocated in each case to different part-webs (10a, 10c), and that each sensor unit (31) is configured so as to detect a longitudinal edge of the part-web (10a, 10c), allocated to it and deflected laterally by the spreading device (4).
12. Apparatus according to any one of the preceding claims, characterised in that the sensor units (21,21',31) are formed at least partially by ultrasonic sensors.
13. Apparatus according to any one of the preceding claims, characterised in that the sensor units (21, 21', 31) are configured at least partially in fork shape or U-shape, and exhibit two mutually opposed limbs.
14. Apparatus according to claim 13, characterised in that a first limb of the sensor unit (21, 21',31) comprises a sensor for emitting a measurement signal, and a second limb of the sensor unit (21, 21',31) comprises a receiver, which is configured to receive the measurement signal.
15. Apparatus according to any one of the preceding claims, characterised in that the sensor units (21, 21', 31, 31', 41, 41') can be adjusted by means of a motor transversely to the conveying direction (FR) of the web material (10) or of the part-webs (10a, 10b, 10c).

Images