EP2535153A1 - Three-knife trimmer - Google Patents

Abstract

The three-cutter has the head and foot cutting portions that are arranged between the press laths (4) and conveyor belt (2). Three cutting units are provided with the cutter guide portion (7). A supporting bar (1) is arranged between conveyor belt and cutter bar (3). The two ends of the supporting bar are connected with the cutter guide portion. The zigzag strips (1a) are formed in the middle of the supporting bar.

Description

Technical environment

The invention relates to a three-knife trimmer for book or booklet block, in which in one or two cutting stations a head-footcut and frontal cut of the blocks in scissor cut against counter knife or crushed against cutting strips, with a total of three cutting units for head, foot and front, the each consist of knives, pressure bars, counter-cutting edges and the associated drive elements, a feed station, an export station and a transport device, which transports the blocks from the import via the two cutting positions in the export in steps.

State of the art

An essential process step in the production of books and brochures is the three-side trimming. A block is cut at a standstill at the head, foot and at the front, while it is held exactly in position.

Processing individual books requires minimal set-up time. It is optimal if the format adjustment can take place during ongoing material transport. The cut quality should be as good as it is standard in a normal production. Achieving the optimum cut quality requires that the block is pressed over the entire surface during the cut.

The personalized design of books with individual formats was made possible by digital printing and must be made possible in the print finishing in economic and technical terms.

The operation of the mini pads must be extremely safe and possible without specially trained personnel. Production committee and setting committee must be avoided.

Three-side trimming is usually carried out in a station by cutting the block pressed between a cutting table and a press plate in a single operation in a first operation on the head and foot and in a second operation on the front. The order of the cuts can also be reversed. The blades cut in a squish cut against cutting edges. When cutting, the knife penetrates slightly into the plastic cutting bar.

The movement of the knife takes place obliquely against the vertical at an angle of about 20 ° to 45 °. They make a slightly oscillating movement, whereby they are slightly unparallel with respect to the table at the incision in the block and thus not abruptly cut across the entire width in the block. In the lowest position, the knife edges are parallel to the table. When cutting the block between a plate corresponding to the format and a table corresponding to the format is pressed over the entire surface, whereby cutting errors such as a mushroom cut are avoided. The format-dependent tables and press plates must be exchanged for each format. For small runs and especially for individual books such machines are completely unsuitable because of the set-up time.

In the US 200210148339 (Zechini ), the pressing is done by pressure bars, which are set on the head and foot together with the knives on Formathöhe and are stationary on the front and which are all pneumatically or hydraulically operated separately. They press the block against cutting edges, which are adjusted to size on the head and foot with the knives and are fixed on the front. The lack of full-surface pressing does not allow optimal cutting quality There are also known three-knife trimmer, where working in two positions in a row. The head and foot cut takes place in one position and the front cut in the other position.

In the US3722336 (Sarring ) introduces a three-knife trimmer, which performs head-foot trimming and frontal cutting in succession in two separate stations. There are three cutting units available, of which the head and the foot cutting unit are adjustable to format height and the front cutting unit is stationary integrated into the frame. The cutting units contain knife guide, pressure bars and counter cutting. In order to avoid the sagging of the blocks, support rails are used in the region of the head and foot knives between a centrally arranged transport belt and the head and foot cutting units, as a result of which no full-area pressing is achieved and the cut quality suffers.

In the EP 1132183A2 (Horizon ) a further possible solution is proposed. Side cut and front cut are made in different positions. There are separate cutting units for head-foot and front section, wherein the head cutting unit and the foot cutting unit are mutually adjustable according to the format and the front cutting unit is stationary. Knife, pressure bar and cutting bar are each located on a common frame. The knives are driven by cranks and linkage from a common motor. The pressure bars are moved by spindles from another common motor. The block is transported between head and foot unit by a pair of pliers. The pressing takes place only by strips next to the knife.

In order to achieve a flatness of the block for an exact cut, format-dependent patches are used between the clamp transport and the cutting units for the head and foot. For individual products and very small runs, replacement of the filler pieces is not acceptable. If one dispenses with the format parts, cutting differences such as e.g. Mushroom cut, i. Overall, a poor cut quality.

In the EP1215021A2 (Wohlenberg ), the block is clamped at the head, foot and front between cutting bars and pressure bars. It is proposed here not to press the block in the area between the mutually adjustable on form height cutting bars, but to support. For this purpose, a support surface corresponding to the smallest format is available in the middle. The free area between this middle support is then covered by a flexible band that adjusts like a roller blind on the format height during format adjustment and can prevent extreme sagging of the block when cutting. This tape is by no means able to avoid buckling during pressing and thus cutting deviations.

The middle support is opposite to the size of the smallest format corresponding ram, which presses the block in the cut only in the middle, which although format parts are avoided but no good cut quality can be achieved.

In the DE 10101843B4 , as well as in the US2009 / 0165616 and the EP 1225015 (Rathert / Muller Martini ) proposes a solution of a 2-station three-knife trimmer with 3 compact cutting units, where in the first station of the head and foot section and in the second station of the front section takes place.

In the front cutting station, the block is pressed over its entire surface during cutting by means of a press plate and a table which cover the largest format.

In the head and foot cutting station, the block is pressed next to the knives by cutter bars and pressure bars Between the recess in the middle for the feed dog and the cutting bars below or the pressing bars at the top, telescopic intermediate pieces are provided, which provide for the flatness of the block when cutting. They usually replace strips or format parts used as support. It is envisaged to make the telescoping intermediate pieces like a roller shutter, wherein the one side of the shutter is attached to the cutting bar or the pressure bar and moves horizontally in format adjustment. The other end is deflected next to the central transport in a radius down or up.

This creates the disadvantage that in the transport nip, through which the conveyor runs, and next to the deflection of the roller shutter support is not supported and not pressed area of the block, which in particular bulges elastic paper, which can lead to cutting deviations. Due to the flat design of the shutters, which are worn only at the ends of the shutter members, only a minimal pressure can be generated.

The alternatively proposed solution for the design of the telescoping intermediate pieces as accordion or bellows is in principle a variety of load-bearing lines that have more or less depending on the format and run parallel to the head and foot knife. Between the webs can the paper Wavy bulging parallel to the head and foot and thus cutting inaccuracy arise.

The telescoping spacers are mechanically sensitive and subject to constant adjustment, e.g. with single-book production the danger to be jammed. Because of the lack of format parts and thus short set-up time, this version is suitable for processing small runs and only limited for single-book production. Since the telescopic spacers do not allow 100% pressing during cutting, the quality is limited.

Object of the invention

The present invention is based on the object to provide a three-knife trimmer, which is specially designed for the requirements in the processing of individual books and short runs. The main requirements are: extremely short changeover time and good cutting quality.

Solution of the task

The object is achieved in that the blades cut against cutting edges or counter blade, that the block is held at the top and bottom section and the front section by pressure bars next to the knives and that in the format-dependent variable space between the cutting edges or counter knives one hand and the space between the pressure bars on the other hand, a plurality of zigzag-shaped support webs are arranged.

The cut is made by three cutting units, which can be accommodated in one or preferably in two stations. The head unit and the foot unit are arranged on a frame format adjustable block height, the front cutting unit is fixedly mounted on the frame.

The cutting units comprise a knife guide, wherein the knife is guided in a conventional manner in a skew-cut movement, a pressure bar, which is driven vertically, for example via racks, and a cutting table, which carries a removable plastic cutting strip.

The knife movement takes place in the usual way via a crank mechanism with a crankshaft, a crank, a coupling rod or a control cam with transmission linkage. This achieves a high rigidity and accuracy of the lower position of the knife. The units can be driven by a common drive or by individual drives. The movement of the pressure bars can be done by control curves on the blade drive, by separate motors, pneumatic cylinders or hydraulic cylinders.

The transport of the blocks through the machine is preferably carried out by an upper belt and a lower belt. The straps are soft and non-slip to prevent print marks on the paper and have recesses in the places, regardless of the format of the block back. They close for transport and lift the blocks slightly above the table level, so that no marks are created on the books during transport due to friction against support elements and pressing elements. For this they are slightly ahead of the cutting table level or the press level.

After the end of the transport stroke, the belts open so far that the surface forms a plane with the pressure bar or with the cutting bar. The upper belts are connected to the movement of the pressure bars and thus follow the stroke of the pressure bars in addition to their own opening and closing movement. The belts thereby make a contribution to achieving a full-surface support of the blocks.

To achieve high cutting quality, a full-surface planning of the block and a strong pressure right next to the knife edges is essential. This is particularly important for the processing of digital prints, which are primarily used for individual books and are very puffy due to the ripple due to strong drying when printing the bow and have many air pockets. Only a whole-area pressure can prevent waves, such as would occur on the parallel to the knives running recesses in the table, as cutting inaccuracy. Ripple of the outer leaves results in a length error due to the bulge and this then leads to mushroom cut.

If the cut is carried out in two stations, it is easy to realize a whole-area pressing with a tabletop and press plate that corresponds to the largest format for the front cut.

At the head and foot station, the gaps between the belt conveyor at the bottom and the cutting bars and between the belt conveyor at the top and the pressure bars must be filled in such a way that no wave formation with wave direction parallel to the knife results, and a strong pressing takes place directly next to the cutting plane.

This effect is of course easy to achieve with flat, exactly adapted to format patches, the replacement and preparation for the production of short runs and individual books would not give an acceptable set-up time.

To solve the problem, the technical teaching described above is proposed.

Several support webs are arranged horizontally displaceable in the intermediate region. They are guided outside the format in guides. The support webs have recesses in the format area at the top, in which zigzag-shaped strips along the webs are inserted flush with the edges. The upper edge is exactly flush with the cutting edge plane and the surface of the lower belt or the pressure bar plane and the surface of the upper belt.

For small format, the zigzag strips are tightly nestled. Likewise, the support webs are close together. With increasing enlargement of the block format, the distances of the webs are larger. It remains with the largest format but with a positive overlap of the adjacent zigzag stripes.

The support webs are guided among each other by guide pins, whereby the maximum distance is limited and the support webs are held in a vertical position. In miniature format, these bolts can dip into the carrier of the belt conveyor or into the cutting bars or pressure bars.

Although, of course, there are gaps between the zigzag strips, there can be no wave formation on the block because a wave can not follow the zigzag shape, but only a straight line.

The top edges of the zigzag strips are rounded and polished, so that no pressure markings are created at the relatively low pressure force. The risk of sanding marks is less than with closed boards, because dust grains come out of contact behind the zigzag strips, and less than with straight lands, because there is no linear contact with the paper in the direction of movement. In addition, the block is lifted by the transport belt during transport and thus has no or only minimal contact with the supporting grid consisting of the supporting webs.

The zigzag-shaped support webs may alternatively be made in elastic material such as rubber. In order to keep the zigzag shape, they are then reinforced on the support webs with equally zigzag-shaped metal strips. The free portion of the elastic zigzag strip may collapse or buckle upon contact with the block.

The contact area with the block is soft. Pressure marks are avoided if the block in the back is slightly thicker. This is less important for hard block processing than for softcover processing.

The elastic inserts in the support webs are preferably carried out only at the top in the press plate plane. At the bottom of the cutting plane, they could interfere with transport due to a higher coefficient of friction if the block is not lifted during transport.

The smallest format results from the sum of the thickness of the support webs plus transport and cutting strips. The largest format results from the width of the extended support webs minus a slight overlap plus transport belt and cutting strips. With a 3 mm support web thickness and a zigzag width of 25 mm, this results in a very large format range.

In a one-station trimmer, according to a known design without a trimming table, the front trimming bar runs at right angles directly in front of the ends of the height-adjustable head and foot trimming strips. When adjusting to a small format, it projects laterally beyond this. The area between a central fixed beam, in which eg a transport belt can be located, and the Cutting bar on head and foot is filled by supporting grid of zigzag-shaped supporting webs. The support webs reach up to the front cutting bar.

In order to avoid the replacement of a full-surface format-matched ram, pressing bars are provided in addition to the cutting planes of the head and foot knives, which are set to format together with the knives. The gaps between a central solid pressing beam, e.g. can also accommodate a transport belt, and the pressure bars for head and foot are in turn filled by support grid with zigzag-shaped support webs. In the area of the central press beam, which extends directly to the cutting plane of the front knife, this takes over the pressure bar function. However, it is not sufficient between the central pressing beam and the head and foot pressing strips to let the supporting grid close to the front knife. In addition to the front section there would be no continuous pressing line but only points through the ends of the zigzag webs. This could result in cutoffs and marks on different papers.

There is therefore between the support grid and front knife a pressing element consisting of two parts, which are attached to the head and foot strips end and push the free ends when adjusted to a smaller size in the middle fixed press beams, for which they are deflected by 90 ° become. The central pressing beam contains two slots for this purpose. The front press members are formed, for example, of thick belts which are deflected to be deflected into the slots of the central press beam by slotting on the inner radius side. They are supported at the top by a frame which is connected to the central pressing beam, and in which the support webs are arranged with the zigzag plates slidably in grooves. The pressing belts thus form a pressing surface along their front diameter corresponding to their thickness. In the deflection area of the belts, the central pressing beam takes over the pressing function.

figure description

Fig. 1

eine Draufsicht auf die Tragstege mit Zickzackblechen bei Größtformat,

Fig. 2

einen Schnitt durch die Kopf- und Fußschneidstation rechtwinklig zu den Messern,

Fig. 3

einen Querschnitt parallel zu der Kopf- und Fußmesserrichtung,

Fig. 4

einen Schnitt durch einen Tragsteg mit elastischem Zickzackeinsatzstück,

Fig. 5

eine Draufsicht auf einen Zickzackstreifen mit elastischem Einsatzstück,

Fig. 6

einen Schnitt durch einen Ein-Stationen-Dreischneider parallel zu Kopf- und Fußmesser,

Fig. 7

eine Draufsicht auf die Schneidtischebene eines Ein-Stationen-Dreischneiders,

Fig. 8

eine Draufsicht auf den Pressleistenbereich eines Ein-Stationen-Dreischneiders,

Fig. 9

einen Schnitt rechtwinklig zu Kopf- und Fußmesser eines Ein-Stationen-Dreischneiders und

Fig. 10

eine perspektivische Darstellung eines Tragsteges mit Zickzackblech.

An advantageous embodiment of the invention is described below and illustrated in the following figures. It shows:

Fig. 1

a top view of the support webs with zigzag sheets at maximum size,

Fig. 2

a section through the head and foot cutting station at right angles to the knives,

Fig. 3

a cross section parallel to the head and Fußmesserrichtung,

Fig. 4

a section through a support bridge with elastic zigzag insert,

Fig. 5

a top view of a zigzag strip with elastic insert,

Fig. 6

a section through a one-station trimmer parallel to head and foot knife,

Fig. 7

a top view of the cutting table level of a one-station trimmer,

Fig. 8

a top view of the pressure bar area of a one-station trimmer,

Fig. 9

a section perpendicular to the head and foot knife of a one-station trimmer and

Fig. 10

a perspective view of a support bar with zigzag.

In the head and foot cutting station are between the pressure bars and the top belt and between the counter-bar and the bottom belt empty areas in which the product could sag, with the size of the empty areas changed depending on the format height.

The proposal to close these areas provides in accordance with Fig. 1 to 3 in that a plurality of support webs 1 are mounted between the lower transport belt 2 and the cutting bar 3 with the pressure bars 3a and the upper transport belt 2 and the pressure bars 4 and are mounted laterally displaceable in the guides 7.

On the support webs 1 zigzag-shaped strips 1a are mounted in recesses, such as Fig. 10 shows. They nestle in the smallest format, as in Fig. 1 shown. The minimum distance between the center of the conveyor belt 2 and the cutting plane of the knife M is K corresponding to half the smallest format. In the largest format still just a coverage ü of the adjacent zigzag-shaped strips remains 1a. The maximum distance between the center of the transport belt 2 and the cutting plane of the knife M is G, corresponding to half the largest size. There is no unsupported zone that runs parallel to the head of the block. It arises Although cavities between the zigzag strips 1a, but allow no wave formation on the block. Sagging and wavy bulging and thus a deviation in the cut of the head and foot cut are prevented.

So that the webs remain perpendicular to the horizontal adjustment v, each support web 1 has at least one guide pin 20 which engages through a plurality of adjacent webs. The guide pins 20 for the various support webs 1 are distributed over the entire web length attached. When sliding to the smallest size, the guide pins can slide into the transport area in the middle between the pre-grooving 2a and the Rücktrumm 2a of the conveyor belt 2, as in Fig. 2 to see where only one connecting pin for a support bar is shown left and right.

The support webs 1 are guided at the ends by guides 7. These have grooves 7a, protrude into the lugs of the support webs 1 and where the support webs 1 are displaced to format.

In order to get no pressure marks in products with an arching back through the zigzag strips, in the region of the position of the back in a recess in the zigzag strip 1a, an elastic member 1b is preferably used made of rubber (see Fig. 3, 4 and 5 ).

So that the elastic member 1b can hold its zigzag shape, it is reinforced at the transition to the strip 1a by a sheet metal strip 1c overlapping the parts 1a and 1b, a part of the strip 1b projecting freely by the dimension x and thickened or swaged by a thickening Spot can dodge.

The insertion of the elastic part 1b takes place only at the top in the press plane. At the lower table level, the zigzag sheets are made of a low friction material with a polished, rounded top edge so that individual sheets of delivered blocks do not get caught.

So that the imported blocks have no friction on the lower support grid of support webs 1 and grinding marks are avoided, the block is at Transport by the Vortrumm 2a of the lower belt 2, for example, a pneumatic cylinder 8 slightly raised by the stroke h1.

When pressing the block before cutting and during cutting, the surface of the protrusion 2a of the lower belt is flush with the supporting grid and cutting edges at a height.

The upper conveyor belt 2 tensions the block against the lower belt during transport. The upper support grid with the guides 7 and the pressure bars 4 are in a position around the stroke h2 ventilated relative to the block.

When pressing are support grid, Vortrumm 2a of the conveyor belt and pressure bars on the same level and press on the block. The protrusion of the upper belt has to compress to the stroke h2, for. over the spring 9.

If a cylinder is used instead of the spring, a short-term release of the transport belt can be achieved for an additional alignment of the block in the cutting position.

For adjustment to block thickness, the guides 7, the pressure bars 4 and the upper conveyor belt 2 are adjusted together in height.

The supporting webs 1 with the zigzag strips 1a can also be used in a one-station three-knife trimmer, cutting bars 3 with cutting strips 3a being provided in a manner known per se on the head and foot, which can be adjusted to form height via spindles 11 in accordance with the adjustment path v (please refer Figure 6 ... 9 ). End of the head and Fußschneidkisten is the front cutting bar 10 with the cutter bar 10 a, whose length l corresponds to the largest format, and which protrudes on both sides depending on the format more or less on the head and Fußschneidleisten.

In the middle is a fixed table bar 12, in which, for example, a transport belt can be accommodated, which brings the block up to the cutting position. The table bar is firmly connected to the front cutting bar 10 and the guide 7 and fixed to the machine frame. Between the cutter bar 3 and the central table bar 12 arise empty spaces whose size depends on the format. It is intended to fill the empty areas by supporting webs 1 with zigzag strips 1a. The support webs are guided in grooves 7a of the guide 7 and in grooves 13 of the front cutting beam 10. This creates a continuous support surface.

In addition to the head and foot knives M are the pressure bars 4. They are set together with the knives M by means not shown adjustment to block height.

In the center of the machine C is a narrow central pressing beam 14, which is lifted by the stroke h3 or lowered for pressing on the rod 14a with means not shown in the usual way. It reaches right up to the cutting plane of the front knife FM. At the central pressing beam 14 are the end of the guide 7 with the grooves 7a and the guide 15 with the grooves 15a.

The guide 15 must cover the largest format and is therefore in front of the pressure bars 4 and the head and foot meter M for smaller formats. So that the agitated movement a of the knife M does not collide, the guide 15 is arranged higher.

The empty areas between the central beam 14 and the pressure bars 4 are filled by support bars 1 with zigzag bars 1a, which are guided in the grooves 7a and 15a, respectively.

Since the zigzag strips 1 a are not suitable to produce the pressing pressure in addition to the front knife, are located next to the front knife FM elastic strips 16 which are connected end to the head and foot press strips 4, and the adjustment of the head and foot press 4 Format slide with their free end over a deflection with the radius R in slots 17 of the central press beam 14. The elastic pressure bar is realized for example by a strip of a rubber-like material greater Shore hardness of the thickness d, which is made bendable by notches.

To record the pressing force, the elastic pressure bar 16 is supported upwardly by the guide 15.

In the area of the possible back position, elastic regions of the zigzag strips can again be used as previously described.

The central press beam 14 is recessed outside the miniature size on the block contact side and padded with an elastic material such as foam so that thicker block spines are not crushed.

When transported through a top belt and a bottom belt, the top belt has recesses in the coating at the location where the block spine is.

Claims (14)

Three-knife trimmer for book or booklet blocks, in which one or two cutting stations perform a head-footcut and frontal cutting of the blocks in a scissor cut against a counter knife or in a squeeze against cutting bars, with a total of three cutting units for head, foot and front, each consisting of knives, Pressure strips, counter-cutting edges and the associated drive elements, a feed station, an export station and a transport device which transports the blocks from the import via the two cutting positions to the export in steps,
characterized in that
cutting the blades against cutting edges or counter blade that the block is held at the top and bottom section and the front section by pressure strips next to the knives and that in the format dependent variable space between the cutting edges or counter knives on the one hand and the space between the pressure bars on the other hand, a plurality are arranged by zigzag-shaped support webs. Three-knife trimmer according to claim 1,
characterized in that
in a one-station three-knife trimmer cut against cutting strips, the front cutting bar fixed to the end of the shape height adjustable head and Fußschneidleisten and arranged at a right angle to these, and that the front pressure bar automatically in their length to the distance between head - and foot knife according to the format height. Three-knife trimmer according to claim 1
characterized in that
the transport of the blocks through a arranged in the center of the machine transport device with belt and upper belt takes place, which clamp the blocks from above and below and transport in steps. Three-knife trimmer according to claim 3,
characterized in that
the upper belt and the lower belt are vertically movable and form a plane with the cutting strips or the pressure strips as part of a support plane in the closed state and project in the released state relative to the press belt plane or the cutting edge plane, so that the block can be transported without friction. Three-knife trimmer according to claim 1,
characterized in that
in a single-station cutter and in the head and foot of a two-station cutter both sides both between the pressure bars and the upper conveyor belt and the cutting bars and the upper conveyor belt in order to adapt to the format height each have a plurality of support webs are provided on different formats are displaced and form a complete table level or press level. Three-cutter according to one of claims 1 to 5
characterized in that
in the format range, the support webs are excluded on the block contact side and zigzag-shaped strips are inserted flush with the edge of the recess, wherein when adjusted to small formats, the zigzag contours are telescopically. Three-knife trimmer according to claim 6,
characterized in that
in the largest format, the contours of the adjacent zigzag stripes still just overlap. Three-knife trimmer according to one of claims 1 to 7,
characterized in that
the support webs are guided at their ends relative to the frame in height by guides, for example, the support webs have at their ends pins which are displaceable in a groove darführung perpendicular to the head and foot knives. Three-knife trimmer according to one of claims 1 to 8,
characterized in that
all support webs are provided with at least one guide pin attached thereto, which passes through the adjacent support webs and holds the support web in the vertical direction and prevents too large a distance between the support webs. Three-knife trimmer according to claim 1,
characterized in that
when performing top and bottom incision and from the front incision in a station, cut all the knives against cutting edges, with the format adjustable head and foot trimmings end up to the front incision and there is a seamless transition from cutting edge to cutting edge, and that in the middle a stationary central narrow table is present, which is the same height with the cutting strips. Three-knife trimmer according to one of claims 1 to 10,
characterized gakennzeichnet that
next to all knives pressure bars are arranged, which press and hold the block against the cutting strips and that in the middle of a central narrow pressing beam is available, which is adjustable in height to block thickness and which is vertically movable for pressing and airing. Three-knife trimmer according to one of Claims 1, 10 and 11,
characterized in that
The front pressure bar consists of two parts, which are flexible, which are attached to the end of the head and foot press strips and their free Ends at format adjustment. Slide over a 90 ° turn in slots in the central press bar Three-knife trimmer according to one of Claims 1, 10, 11 and 12,
characterized in that
In the voids between the cutting strips and the central table on the one hand and between the pressure bars and the central pressing beam on the other hand support webs are arranged with zigzag strips. Three-knife trimmer according to one of claims 1 or 13,
characterized in that
In the area of the possible back position, the zigzag plates of the press plane have elastic inserts.

Images