EP0000411B1 - Method and apparatus for cutting sheets into individual leaves, and the subsequent orderly stacking of same - Google Patents

Description

The invention relates to a method for cutting sheets into single sheets, in which the material to be cut is fed to a conveying device and brought to a cutting device, the cutting always taking place when the sheets have been conveyed through the cutting device by a cut length.

When producing blocks, brochures, books or the like, there is the problem that the mostly different pages or sheets printed on large sheets have to be brought into an orderly order before binding or stapling. The usual procedure is to fold the sheets several times, and then to cut and separate the individual sheets at the desired locations. The disadvantages of this known method are the relatively complicated folding process step, which is difficult to insert into continuous processing and requires separate machines, and on the other hand an increased waste of paper.

From GB-PS 1311483 a device for cutting paper webs into single sheets is known, in which the web is divided longitudinally into parallel strips in a first operation and these strips are guided one above the other. In a further step, the strips run through rotating cutting cylinders, which are provided with knives parallel to the axis of the cylinders. Endless conveyor belts remove the resulting single sheets. The known device is not applicable when sheets are to be cut into single sheets. In addition, it does not allow the individual sheets to be stacked in an orderly manner.

US Pat. No. 2,639,772 shows a device for tearing sheets into single sheets, the material to be torn being brought to a first separating device and the tearing always taking place when the sheets are conveyed through the separating device by a width of the single sheets. The sheets are then placed on top of one another in a scale before further separation. The known arrangement has the disadvantage that the sheets are fed one after the other to the first separating device and have to be processed further. Only when all single sheets of a sheet are available can you start feeding a new sheet. There is therefore no continuous operation, and tearing of sheets is not suitable for the production of printing material. On the other hand, the sheets are not inevitably guided, so that the known device works so imprecisely that an exact cutting is not possible.

The invention has set itself the task of demonstrating a method of the type mentioned, in which a simple and economical way of cutting sheets into individual sheets and a subsequent orderly stacking of the same is possible while eliminating the folding process.

The method according to the invention is characterized in that the sheets to be cut are superimposed in a scale-like manner and are passed through the cutting device by a width of the individual sheets.

Likewise, according to the invention, a device is shown which enables such simplified processing. This device is characterized in that the sheets to be cut are arranged in a scale-like manner on the conveying device, and that the cutting device can be actuated by a width (b) of the individual sheets after the sheets have passed through.

Likewise, according to the invention, a device is shown which enables such simplified processing. This device is characterized in that a conveying device is provided, to which sheets are fed individually or in groups, and which conveys the sheets in the direction of a cutting device, and in that the cutting device is actuated whenever the scales lying one above the other by the width of the individual sheets they were promoted through.

• Fig. 1 eine Draufsicht auf eine schematisch dargestellte Vorrichtung zur Durchführung des Verfahrens, gemäss einer ersten Alternative,
• Fig. einen Schnitt längs der Linien A-A in Fig. und
• Fig. 3 einen Schnitt durch die Vorrichtung gemäss Fig. 1 längs der Linien B-B;
• Fig.4 eine Draufsicht auf eine schematische Darstellung der Vorrichtung zur Durchführung des Verfahrens, gemäss einer zweiten Alternative,
• Fig. einen Schnitt längs der Linien A-A der Fig. 4 und
• Fig. 6 einen Schnitt durch die Vorrichtung gemäss Fig. 4 iängs der Linie B-B und
• Fig. 7 ein Beispiel eines Bogens, der in der mit aufsteigenden Ziffern bezeichneten Reihenfolge zu Einzelblättern zugeschnitten werden soll.

Further features of the invention and their advantages result from the following description with reference to the drawings. Show it

• 1 is a plan view of a schematically illustrated device for performing the method, according to a first alternative,
• Fig. A section along the lines AA in Fig. And
• 3 shows a section through the device according to FIG. 1 along the lines BB;
• 4 shows a plan view of a schematic representation of the device for carrying out the method, according to a second alternative,
• Fig. A section along the lines AA of Fig. 4 and
• 6 shows a section through the device according to FIG. 4 along the line BB and
• Fig. 7 shows an example of a sheet which is to be cut into single sheets in the order designated by ascending numerals.

In the method according to the invention, material sheets 1 with the dimensions WxH are to be processed into an ordered stack 11 of strips. In most cases, one would like individual pages with a size of wxh, so that this first process is followed by a processing process of the same type, which is preferably perpendicular to the material flow of the first process.

The material sheet 1 consists for example of paper, cardboard, plastic, metal foil or similar flat material. The intermediate product (which in some cases can also be the end product) is an ordered stack of strips with dimensions bxH and the end product is an ordered stack of single sheets with dimensions bxh, in the order as can be seen in FIG. 7. Instead of a simple material sheet, folded sheets as well as sheet groups consisting of several sheets can be used.

In the first alternative method according to the invention, the movements are gradual. As can be seen from FIGS. 1 to 3, a conveyor table 4 or a similar depositing device is provided, which can be moved horizontally in the direction of a cutting device 7, 8 and back again into the starting position. A hold-down device 2 can be moved in a predominantly vertical direction and serves to hold down the sheets located on the table 4 and at the same time as a stop for new material sheets placed on the table.

In front of the cutting device there is a storage table 5 on which the scale-like layers of material sheets 1 are conveyed from the conveyor table 4. A further hold-down device 3 is arranged above the table 5 and is operated alternately with the hold-down device 2.

The material sheets are conveyed in incremental units that correspond to the width b of the single sheets.

The device works as follows: A sheet of material 1 is placed on the table 4, the table moves each sheet of material inserted by the format width b to be cut in the direction 6 to the knife 7, 8. At the foremost point of its movement, the sheet is through the lowering hold-down 3 held. When the hold-down device 2 is open, the table returns to its starting point without a material sheet and enables a new material sheet to be placed on it. The process is repeated continuously, the hold-down device 2 holding the scale-thickening material in place during the advance of the table and thus ensuring the safe feed 6. When the table returns (opened hold-down 2), the lowered hold-down 3 prevents the material from going back. The material thus transported under the knife 7, 8 is cut. Material strip layers with the dimensions wxH are created. Depending on the size BxH of the original format and height b of the single format, the number of material strips is always the same after the setting has been made. Now the process of scaling is repeated in the lateral direction. This time the material strip layer 11 is the starting product. It is placed on the back and forth table 12. The lateral feed in the direction 15 to the knife 13 corresponds to the dimension h. The hold-down device 14 prevents the material strips from remaining. Finally, a stack in the final format bxh is cut from the knife 13.

All individual formats of a sheet of material 1 are assigned certain individual formats of the other sheets of material because of the always the same position. Therefore, individual formats can be processed (printed) differently before the collection process, the order of processing e.g. by the printer, in a desired order.

The reference numerals 16 and 17 indicate the cutting planes for cutting the material strips 11 and the final formats. 9 and 10 denote the extremely small amount of paper waste that results for each complete stack of strips. In Fig. 3, 18 denotes the finished stack, arranged in the desired order, which is now further processed e.g. Stapling or sizing.

The step unit of the conveyor table 4 is preferably adjustable, so that different widths b can be produced. The same applies to the conveyor table 12 of the cross conveyor. The transition from longitudinal to transverse conveying takes place mechanically or pneumatically by gripping arms or similar movement means, and always when a corresponding stack 11 has been completely built up.

It is essential in the invention that the different movements are synchronized with one another, that is to say that the feeding of the material sheets 1, the movement of the table 4 and the hold-down devices 2, 3 as well as the actuation of the knife 11 and also the removal of the material strip 11 to one another in one fixed relationship, which is adjustable depending on the dimensions of the desired final formats.

4 to 6 show a further embodiment of a device as it can be used for another alternative of the method according to the invention.

Conveyor belts 21, 42, which could also be replaced by conveyor drums, serve as the conveying device here. Although the first alternative of the method according to the invention, namely step conveyance, could also be carried out with the conveyor belt, this conveyor belt is particularly suitable for continuous processing. The conveyor belt moves in the direction 24, preferably at a constant speed. Material sheets 23 are fed to it step by step, the feed speed depending on the conveying speed of the conveyor belt 24 and on the dimensions of the final formats. A plurality of cutting devices 26 can be provided, which are actuated alternately or simultaneously, and also depending on the feed and conveying speed of the material sheets.

The cutting devices 26 are shown here as a guillotine knife, hitting against a pad 28 _S, this may be to plan or around rotating suppression ^g knives act. The conveyor belt is made of a resistant material, preferably nylon, which the knives will only wear over the long term. Niederhal ter 25 are pressed against the paper during the cut, these hold-down devices either being moved separately from the knives or attached to them - leaving the cutting edge free. The distance between the knives is preferably adjustable so that different formats can be processed. This is indicated by arrow 27. This type of processing in turn creates a stack of material strips 29 which is transferred to the cross conveyor by suitable gripping means. The cross conveyor can be constructed in the same way and work as the device just described. However, a combination with the device according to FIGS. 1 to 3 is also possible, just as the longitudinal conveying according to alternative 1 and the transverse conveying according to alternative 2 could run.

4 to 6 show an alternative form of a hold-down device, which is designed as a conveyor belt 22 in this second embodiment. One or more adjacent rollers could also take the place of the conveyor belt.

• die Messerebenen sind mit den Bezugszeichen 40 und 41 versehen; weitere entsprechende Teile sind Förderband 42, Gegenplatte 47, Niederhalter 43, Niederhalter 44, Messer 45 und Pfeil der Verstellmöglichkeit 46.

As already mentioned above, a similar arrangement is provided for the cross conveying, in which the parts are provided with the following reference numerals:

• the knife levels are provided with the reference numerals 40 and 41; Further corresponding parts are conveyor belt 42, counter plate 47, hold-down device 43, hold-down device 44, knife 45 and arrow of the adjustment option 46.

• Ein Materialbogen 23 mit den Abmessungen BxH nach dem anderen wird auf einem ständig in Richtung 24 laufenden Transportband 21 abgelegt. Aus der zeitlichen Differenz zweier abgelegter Materialbögen ergibt sich eine schuppenförmige Ablage. Die Geschwindigkeit des Transports ist so einzuregulieren, dass die Überlappung gleich der Formatgrösse ist. Das so schuppenförmig laufende Material wird durch den mit gleicher Geschwindigkeit laufenden Niederhalter 22 festgehalten. Das oder die Messer 26 schneiden die Materialstreifenlagen 29 ab. Diese werden auf einem zweiten Transportband 42 ebenfalls schuppenförmig abgelegt. Die mitlaufenden und festen Niederhalter 43 bzw. 44 ermöglichen das Abschneiden der Endformate durch das oder die Messer 45.

The operation of this device, apart from the continuous delivery, is similar to that of alternative 1. The following process takes place in detail:

• A sheet of material 23 with the dimensions WxH after the other is deposited on a conveyor belt 21 which is constantly running in the direction 24. The time difference between two stored material sheets results in a scale-like storage. The speed of the transport is to be adjusted so that the overlap is equal to the size of the format. The material, which runs in the form of a scale, is held in place by the hold-down device 22, which runs at the same speed. The knife or knives 26 cut off the material strip layers 29. These are also deposited in a scale-like manner on a second conveyor belt 42. The moving and fixed hold-down devices 43 and 44 enable the end formats to be cut off by the knife or knives 45.

The second alternative of the method according to the invention has the advantage of continuous machining, it also being possible to increase the speed considerably.

If the material sheets are conveyed quickly, one should also consider lowering the speed during the cut in order to obtain an exact cut.

The first dimension in the description was the width of the individual formats. Of course, processing can also start with the other dimension, namely the height.

For the sake of clarity, it should be pointed out again that in the case of transverse processing, one layer of material strip corresponds to one sheet of material 1 in longitudinal processing. The layers of material strips are thus lined up in a scale-like manner on the conveyor table 12 or on the conveyor belt 42.

The method according to the invention is also particularly suitable for tear-off calendars.

Claims (10)

1. A process for cutting sheets into individual sheets where the material to be cut is supplied to a feeding device and is fed to a cutting device the cutting being effected whenever the sheets have been fed through the cutting device by the cut length, and for orderly stacking the individual sheets, characterized in that the sheets (1) to be cut are layed one upon the other in a partially overlapping manner and are fed through the cutting device (7, 8) by the width (b) of the individual sheets.

2. A process according to claim 1, characterized in that the individual cut sheets are stacked up until they reach a desired height and are then conveyed away.

3. A process according to claim 1 or 2, characterized in that the individual cut sheets are stacked in a partially overlapping manner and fed through a further cutting device by the height (h) of the individual sheets.

4. A process according to one of claims 1 to 3, characterized in that the sheet supplying, the sheet feeding, the cutting and the conveying away are synchronized with each other.

5. Device for cutting sheets into individual sheets and subsequent orderly stacking of said individual sheets including a feeding device (4) to which the material to be cut is supplied, and a cutting device (7, 8) which is actuated whenever the sheets have been fed through by a cut length, characterized in that the sheets (1) to be cut are arranged in a partially overlapping manner on the feeding device (4) and that the cutting device (7, 8) is arranged to be actuated each after feeding through of the sheets (1) by a width (b) of the individual sheets.

6. Device according to claim 5, characterized in that the feeding device comprises a feeding table (4) which is moved towards the cutting device (7, 8) in stepping units corresponding to the width of the individual sheets and back again and that in the region of the table (4) and/or in the region which is upstream of the cutting device (7, 8) hold down means (2, 3) are provided which hold down the sheets in the forward and backward movement of the table (4) against the table or against a support (5) of the cutting device (7, 8) respectively.

7. Apparatus according to claim 5, characterized in that the feeding device is a conveyer belt (21) or a conveyer drum and that the feeding device (21) is moved in step units which correspond to the width of the individual sheets.

8. Apparatus according to anyone of the preceding claims, characterized in that several cutting devices (26) are arranged in succession in the direction of feeding of the sheets which are actuated alternately or simultaneously.

9. Apparatus according to anyone of the preceding claims, characterized in that the cutting device (7, 8) is of a shears-like construction or has a form of a striking knife (27, 28) of a straight construction.

10. Apparatus according to anyone of the preceding claims, characterized in that the one or more hold down means are in the form of a roller or conveyer belt operated synchronously with the feeding device (21).

Images