FR2801244A1 - METHOD AND DEVICE FOR FOLDING FLAT COPIES OF PRINTED PRODUCTS, AS WELL AS FOLDED AND FOLDING MACHINE - Google Patents

Abstract

The invention aims to avoid ruptures at the folds of the inner layers of printed products, magazines assembled by staples for example. The inner layers are folded by means of members provided with recesses. Thus, the backs of folds (6), in particular of the middle layers (4) of printed products, consist of segments (42) folded longitudinally which alternate with non-folded segments (41) which retain a roundness (8). The staples are placed in the unfolded segments (41). The sharp fold area in the middle of the print is thus better preserved and the detachment of the middle pages is avoided.Applicable to folders installed after presses for newspaper printing.

Description

I The invention relates to a method of folding flat copies of

  printed products and the like, such as printed products produced in presses installed as a result of web printing presses, a device for folding flat copies of printed products and the like, in particular for implementing this process, as well as a folded copy of a printed product or the like, obtained in particular by the above-mentioned process and / or device and a folding machine, in particular a folding machine installed following a printing press and applying

  of the above method and / or device.

  From the state of the art, in particular from document EP 0 663 363 B1, there is already known a device intended to guide strips and having at least one core of a roller on which are arranged annular lamellae, as well as a process for manufacturing this device. The latter is designed to guide strips of paper, textile or plastic and the annular lamellae disposed on the core of the roller are made of elastic material. The slats are placed symmetrically with respect to the median plane in the direction of the axis of the roll core and threaded one at a time.

  following the others, symmetrically, from the middle. They are applied

  axially against each other and together form an almost closed surface. In these annular lamellae, at least one deflection point is provided and their cross section is roughly in Z. When the lamellae are exposed to a radial pressure, caused for example by a tension exerted by a strip passing over the roller, their outer periphery moves axially and symmetrically with respect to the axial median plane. The cylindrical surface, however, maintains parallelism with the axis of the roller. The annular lamellae known by this solution according to the state of the art, are preferably manufactured in

  rubber, natural rubber, plastics or the like.

  Document DE-OS 29 05 548 relates to a folding roller in the lateral surface of which linings of flexible plastic are inserted. Between the linings, the surface areas of the metal constituting the roller were left free, from which the inserted linings protrude radially to a small extent. The linings are prefabricated rings of a plastic material which is slightly elastically deformable and endowed with rubber elasticity for example. The rings can be placed, under prestressing, in annular grooves provided in the lateral surface of the roller and they have, over their entire width, a groove formed by

  grooves oriented at least approximately parallel to the axis of the road

  water folds. The metal areas of the surface, located between the rings, on the contrary have a smooth, non-striated surface. This solution aims to provide a folding roller allowing a particularly safe transport and an unimpeded flow of air, a roller which can be manufactured more simply and more economically, has a longer service life and whose parts mainly exposed to the wear be more

easily renewable.

  From document DE 37 43 642 A1, another folding roller is finally known. This has a part forming a cylindrical core, on which are slidably arranged, for the purpose of forming hollows at predetermined locations, sleeve-shaped surface parts of material endowed with rubber elasticity and surface parts made of form of metal sleeves. In order to maintain the metal sleeves in rotation, carrying externally a knurling, their inner surface has circumferential grooves in which are

  mounted O-rings made of a material endowed with elastic rubber

  tick. These seals allow the axial displacement of the metal sleeves,

  but at all times maintain their maintenance in a fixed place, by rubbing

  ment, in circumferential direction. This solution makes it very easy to adjust the hollows between the different sleeves in

  depending on the linear adhesive applications planned each time.

  In the case of folded multilayer copies, for example of folded products comprising 8, 16, 24, 32, 48 or even 64 pages, a fold failure

  can occur in the innermost layers of the example

  please. When a print of this type is opened, the different layers of which are held together by fasteners such as staples, for example, a fold failure can cause the innermost layer to fall off - also called middle layer - of the copy, it can be a newspaper or a magazine for example, since it is no longer held in place by the staples. It should be noted in this regard that the middle layer is subjected to a sharp bending of about 180, which places very high demands on the printing medium concerned. By printing, subsequent drying, re-humidification and cooling of the web, the printing medium has already been subjected to a succession of alternating thermal influences, which could have modified its mechanical properties in a very unfavorable way. . In particular, the mechanical stability of the strip could have been considerably reduced by embrittlement, so that high consecutive stresses - for example in the form of a sharp folding at 180 - favoring the appearance of ruptured folds. The layers enveloping the middle layer are relatively insensitive to the appearance of ruptured folds since the back of the fold becomes more and more rounded from the layer

  median, with each layer adding around it.

  Starting from the technical problem which has just been indicated and from the solutions sketched out according to the state of the art, the invention aims to avoid the appearance of ruptures of folds in folded copies, in particular of products

  printed, and significantly increase the quality of copies.

  In accordance with the invention, starting from a folding method of example

  please flat, in particular of printed products and the like, the examples

  plaires being composed of several layers and the folding operations producing open ends and closed backs of folds on the copies, this is obtained by the fact that the back of the fold is formed from the inner layers of the copy with interruptions by segments

not folded.

  With regard to the device for folding flat copies, in particular printed products and the like, in particular for placing

  work of the folding process according to any one of the claims

  previous, the copies being composed of several layers and the folding operations producing zones with open ends and zones with closed backs of folds on the copies, the zones with backs of folds being formed on the copies by folding members, the l at least one acts linearly on the layers of a multilayer folded copy, the desired result is obtained, in accordance with the invention, by the fact that the folding members have recesses and form on the layers of the copy a back fold comprising segments folded longitudinally

and unfolded segments.

  The advantages achievable by the solution according to the invention are of various kinds. Thanks to the distribution along the length of the fold back of unfolded areas, the excessive weakening of the print medium is avoided. The unfolded segments in the back of the fold of the innermost layers of a multilayer copy give greater

  mechanical resistance to these layers, which prevents excessive weakening

  sement, parallel to the orientation of the fibers, in the region of the back of the fold of the middle layer in particular. In the backs of folds of the layers thus treated, bridges are formed in this way, formed by the printing medium and offering, thanks to the fact that any weakening by folding is avoided in the areas of assembly of the layers in particular, a base

  reliable for fasteners, such as staples.

  According to an advantageous improvement of the method proposed by the invention, the unfolded segments of the layers located most inside the specimen, remain rounded and thus offer sufficient space for the closure of the assembly elements of the layers of the 'exemplary,

  staples for example. The unfolded segments of the fold back are preferably

  They are placed in the places where the staples are later placed in the copy in order to hold the different layers together. The stapling position and hence the location of the unfolded segments of the back of the fold are preferably provided in places which depend on the format, for example in the head area and the foot area of a copy of format

  A4 or in the edge areas of a delta folded copy.

  In order to minimize the mechanical stress on the print medium, the backs of folds to be produced are preferably parallel to

  the orientation of the fibers in the print medium.

  According to a variant of the method according to the invention, a fold back, provided with non-folded segments which interrupt it, can be formed by driving layers of copies or copies into a slot between folding rollers . The formation of the fold back, proposed by the invention, is thus applicable for producing a second longitudinal fold in a folder; according to another variant of the method, the fold back, interrupted by unfolded segments, is formed during a transverse folding operation during the transfer of layers of a copy from the periphery of a guide cylinder-copies to the guide cylinder copies

  following, constituting for example a folding cylinder with jaws.

  The device proposed by the invention for folding flat copies composed of several layers, comprises folding members provided

  of hollow and forming, on the different layers of a multi-copy

  diaper, a fold back interrupted by unfolded segments. It is advantageous for the hollows of the folding members to have a width corresponding to the longitudinal dimension of an unfolded segment on the back of folds of the layers of a copy. In combination with the longitudinal dimensions thus chosen of the unfolded segments, the depth of the recesses provided in the folding members can create a surrounding space.

  assembly elements, such as staples for example.

  The different hollows of the folding members are preferably arranged according to the format. In particular, recesses for stapling positions of a first folded format may be placed at a distance A from one of the ends of the gross length of the layers of a copy, and recesses for stapling positions of 'a second folded format can be placed at a distance B, from an end of the gross length of the layers of a copy, which corresponds to approximately half of this length. The hollows of the folding members can be produced in the form of circumferential annular grooves and closed in themselves in cooperating folding rollers, which delimit between them a folding slot. According to another embodiment, the recesses are pockets formed in the lateral surfaces of folding rollers. In this case, the length of the pockets in the circumferential direction can be defined by a

  sector in an arc of a circle of the lateral surface of the folding roller considered.

  Finally, the recesses can be provided on a folding knife forming part of a second longitudinal folding device. In this case, the recesses, again arranged according to the format, are formed in the folding edge of the knife, edge by which the knife acts linearly on the layers to be folded of a copy when they are inserted between the folding rollers. The method and the device proposed by the invention make it possible to produce folded copies, each composed of several layers, the ends of which are open and which have an area with a closed fold back, the layers situated inside having a back a fold comprising unfolded segments having a round. The solution proposed in accordance with the invention for forming a fold on flat specimens, whether it is a transverse fold, a longitudinal fold, a delta fold, a double parallel fold or a similar fold is advantageously applicable to folding machines which can be installed following web or sheet printing presses. Such a folder can be equipped with sets of sizes, but it can also be a folder operating without sizes. Next to a possible application in

  downstream of sheet-fed presses, the solution according to the invention is also applied

  cable particularly advantageously to web printing machines, for example to web presses for printing

newspapers or city works.

  According to another aspect of the invention, a folded copy, in particular of a printed product or the like, composed of several layers and having open ends and closed areas on the back of fold, obtained in particular by the process and / or the device according to the invention, is characterized in that the back of folds of layers located inside the copy, comprises non-folded segments having a roundness and

segments folded longitudinally.

  The invention also provides a folder for folding flat copies, in particular of printed products, in particular applying the method and / or the device according to the invention, the copies being composed of several layers and the folding operations producing ends. open and fold backs closed on the copies, the fold back areas of the copies being formed by folding members, at least one of which acts linearly on the flat layers of a copy, a folder which is characterized in that the folding members have recesses and form on the layers of the copy a fold back comprising

  longitudinally folded segments and non-folded segments.

  Other characteristics and advantages of the invention will emerge more

  clearly from the following description of several examples of

  non-limiting embodiment, as well as the accompanying drawings, in which:

  - Figure 1 shows a folded multilayer copy of a printed product

  mé whose back is oriented in the direction of transport and whose ends of the layers are open; - Figure la shows the most inwardly located layer of a copy according to Figure 1; - Figure lb shows the embodiment according to the invention of the back of fold segments of an inner layer according to the method proposed by the invention; - Figure 2 shows two cooperating folding rollers, delimiting between them a folding slot, the peripheral surfaces of which are provided with circumferential recesses located one opposite the other; - Figure 2a shows on a larger scale a hollow formed in the peripheral surface of a folding roller according to Figure 2; - Figure 2b shows a folded example from a folding table and entering a folding slot between two cooperating folding rollers according to Figure 2; - Figure 3 shows folding rollers, delimiting between them a folding slot, in the peripherals of which are formed pockets located one opposite the other; - Figure 3a shows the entry of a multilayer copy into a slot between two cooperating folding rollers made according to Figure 3; - Figure 3b shows the dimensions of the pockets in the peripheral surfaces of the folding rollers according to Figure 3; FIG. 4 is the side view of a folding member in the form of a folding knife which can be driven with upward movements and

  lowering and intended for a second longitu-

  dinal in a folder; - Figure 5 shows the positions of assembly elements in non-folded segments of a fold back for an A4 format and for a delta format; and Figure 6 is a schematic perspective view of a segment not

  folded on a fold back of a middle layer of a multi-copy

folded layer.

  Figure 1 shows a multilayer copy 1 of a printed product. It includes a middle layer 4, which is the innermost layer, as well as other layers 5 which surround it. The back 2 of the copy is oriented in the direction of transport of the copies in the folder, and the open ends 3 are on the opposite side of the folded copy 1. It appears from the representation according to Figure 1 that the layer median 4 has undergone a sharp folding of about 180 in the region of the back 2, while the other layers 5 of the specimen, enveloping the middle layer, have a fold back which becomes more and more rounded as the layer considered is located more towards the outside. These layers, which are located more towards the outside, are less sensitive to ruptured folds because their

  rounded parts are exposed to lower mechanical stress.

  Figure la shows the middle layer 4 of a folded copy 1 like the one shown in Figure 1. The back 6 of this middle layer, shown here on the right side, underwent a sharp bending of 1800, which imposed high mechanical stress in addition to those undergone by

  printing, drying, re-humidification and cooling operations.

  The open ends 7 of the middle layer 4 are shown on the

opposite side to the back 6.

  Figure lb shows a middle layer 4 of an example 1 which has been folded in accordance with the invention. Opposite the open ends 7 of this middle layer 4, there is a fold back which is partially

  provided with a round 8, as described in more detail below.

  Figure 2 shows a possibility of execution of folding members

  capable of producing pleats like those proposed by the invention.

  This Figure shows more exactly two folding rollers 9, 10 which delimit between them a folding slot 11 and whose side surfaces 12 cooperating are interrupted by annular recesses 13 located opposite each other on the two rollers. The first folding roller 9 rotates anticlockwise, along arrow 14, around an axis of rotation 20, while the second folding roller 10, cooperating with the first, rotates in the direction needles, according to arrow 15, about an axis of rotation 21. The folded copies, pressed into the slot 11 by an additional folding member, not shown here, are thus folded longitudinally in a second longitudinal folding device of a folder. During this operation, thanks to the recesses 13 which face each other on the peripheral surfaces 12 of the two rollers 9 and 10, the

  back of the fold, thus formed, is provided with unfolded segments.

  FIG. 2a shows on a larger scale one of the annular recesses 13. It can be seen that this recess interrupts the lateral surface 12 of the first folding roller 9 or the second folding roller 10. The recess is delimited on the sides by two edges 16 and its width 17 is chosen so that the non-folded segments 41 (see FIG. 6), which remain after folding, protrude in length from the joining elements used to join the layers and constituted by staples for example. The depth 18 of the annular recesses 14 can be half a millimeter for example. Thus are formed on the folded layers 4, 5, during the formation of the unfolded segments 41, spaces whose boundaries surround the joining elements

formed by staples.

  Figure 2b shows in more detail the two folding rollers 9 and

  10 cooperants. As part of a second long folding operation

  dinal, a multilayer copy 1, supported at the level of its lateral faces by folding tables 19, is pressed, with the folding back 2, 8 at the front, into the folding slot 11. As a result of the rotation of the two rollers 9, 10 around their respective axes 20 and 21, the fold back 6 is formed on the item, while the annular recesses or grooves which face each other on the two rollers and which are shown here in broken lines, give rise to the formation of the unfolded segments 41 (see FIG. 6) which interrupt the fold back 6. As in the arrangement of the folding rollers shown in FIG. 2, the first folding roller 9 rotates in the opposite direction to the needles a watch along arrow 14, while the second folding roller 10, cooperating with the first, rotates clockwise along arrow 15. The open ends 3 of the copy are shown above the folding table 19 whose

  layout is only shown schematically here.

  Figure 3 shows another embodiment of hollows in

folding members.

  This Figure shows a first folding roller 9 and a second folding roller 10 rotating around their respective axes of rotation 20 and 21. The first roller 9 rotates anti-clockwise

  along arrow 14, while the second 10 rotates along arrow 15.

  In the peripheral surfaces 12 of the two rollers are provided

  pockets 22, the arrangement of which is only shown diagrammatically.

  As in the example shown in Figure 2, the two rollers 9 and 10

  delimit between them a slot in which a folding knife, not shown

  felt here, push in a copy to be folded longitudinally, by

  example in a second longitudinal folding device.

  Figure 3a shows in more detail the entry of an example

  fold multilayer in the folding slot 11 formed between two rollers

  constituting folding members 9 and 10 cooperating according to FIG. 3.

  As already described above, the first folding roller 9 and the

  second folding roller 10 rotate in their directions 14 and 15 respectively

  tives around their respective axes of rotation 20 and 21. The lateral surfaces 12 of these two rollers have the pockets 22 according to FIG. 3, which extend, as indicated by the reference 23, on an arc of a circle in the circumferential direction on the lateral surfaces 12 of the first 9 and the second folding roller 10. It is possible to act on the conformation of the rounding 8 of the fold back 6 of the copy by the choice of the length 23 of the pockets in the circumferential direction on the rollers 9 and 10. The

  open ends 3, 7 of the different layers of the specimen are indicated

  but only schematically here, above the table

folding 19.

  Figure 3b shows in more detail the configuration of the pockets 22 in the lateral surfaces 12 of the first 9 and the second folding roller 10. As the depth 18 of the annular grooves 13 according to Figure 2a, the depth 25 of the pockets is in this case also about 0.5 mm, which is sufficient for the shaping of the unfolded segments in the back of fold 6 on the copies. The length of the pockets 22 in the axial direction It is indicated in Figure 3b by the reference 23, while their extent in

  circumferential direction is designated by reference 24.

  Figure 4 shows a side view of a folding knife making

  part of a second longitudinal folding device.

  In this second longitudinal folding device, itself incorporated

  in a folder, the folding member 26 - that is to say the folding knife -

  cooperates with the folding rollers shown in Figures 2 or 3. The knife 26, animated by up and down movements, pushes the different layers 4, 5 of a folded multilayer copy 1 into the slot it defined by the lateral surfaces cooperating 12 of the first 9 and the second folding roller 10. In the embodiment of a folding knife 26 according to Figure 4, recesses 28 are provided in its folding edge 27

  coming linearly into contact with the different layers of the copy.

  These recesses or notches have a width 30 which determines the length of the unfolded segments 41 (see FIG. 6) in the back of the fold 6. The depth 29 of the different notches is here also only around 0.5 mm, like that of the grooves shown in Figures 2a and 3b, which allows

  to form the unfolded segments in the back of fold.

  In the embodiment according to Figure 4, the folding edge 27 of

  the blade of the knife 26 has three notches or recesses 28.1, 28.2 and 28.3.

  With respect to a vertical reference edge, the first hollow 28.1 is at a distance 38 from said edge, a distance which designates the position of a stapling in the head area of a folded copy having the format A4. The second recess 28.2 from the edge 27 is provided at a distance 39 from the reference edge, which defines the position of stapling of a folded copy in delta format. Finally, the recess 28.3 is located, with respect to the reference edge, at a distance designated by the reference 40 and defining the position of a stapling in the foot area of an A4 format. The annular grooves 13 formed in the peripheral surfaces of the folding rollers 9 and 10 according to Figure 2, as well as the pockets shown in Figure 3, are also located, relative to the reference edge shown in Figure 4, at distances 38 , 39 and 40, so that the notches 28.1, 28.2, 28.3 of the folding knife 26 correspond to the locations of the annular grooves 13 as well as of the pockets 22 in the peripheral surfaces of the

folding rollers.

  Figure 5 shows in more detail the locations of the connecting elements interconnecting the different layers of a copy, as well as, by hatching, the parts removed from the different

  annuities during consecutive operations.

  The middle layer 4 has a gross length 31 from which is

  Vee, in the head area, during subsequent trimming operations, a fall 35 in the form of a strip. Similarly, a drop 37 is removed in the foot area, so that the middle layer 4 of

  the copy is reduced, for A4 format, to a length marked 32.

  The vertical edge 34 is also removed from this middle layer 4. FIG. 5 also indicates the length 33 of a delta-folded copy, for which the middle layer 4 is also suitable. A fall 36 in

  strip form is removed from such a middle layer 4 in delta format.

  Figure 5 shows the location of the different segments not

  folded with the rounded 8 in the back of fold 6 of the middle layer 4. The assembly elements, by which are connected the different layers of the copy - and by which the middle layer 4 is therefore also connected to the other layers of a multilayer copy - are designated by 28.1,

  28.2 and 28.3. Staples are used here for assembly elements.

  They are placed in the unfolded segments, having the roundness 8, for example-

  ple, in relation to the net length 32 of a folded copy of A4 format, at

  the distance A - which can correspond to about 60 mm for example -

  upper and lower ends of this length. This definition

  stapling positions is to be associated with the distances 38 and 40 respectively-

  ment from the head of an A4 size copy.

  It also appears from FIG. 5 that the rounded 8 in the fold back 6 of the middle layer 4 have a length designated in this Figure by the reference 44. It exceeds the length - or height in the representation according to this Figure - of the different assembly elements, staples in this example. When we consider the copy length 33 of a delta folded print, we see that, for this format, the assembly elements are placed, inside the rounded 8, at the positions designated respectively by 28.2 and 28.3 in the back of fold 6 of this delta folded copy. In relation to the upper edge of an A4 folded copy, the upper connecting element for the delta folded copy is located at the

  position 28.2, that is to say at the distance 39 from the upper edge of the A4 format.

  This connecting element at position 28.2 is located at a distance B from the

  upper edge obtained after trimming the fall 36.

  Figure 6 shows partially and on a larger scale the middle layer 4 of a multilayer example. The fold back 6 of this layer comprises non-folded segments 41, only one of which is visible, which alternate with segments 42 folded longitudinally. A rounded 8 is indicated on the unfolded segment 41. This rounded extends over a length 44 which advantageously corresponds to the width 30 of the notches formed in the folding edge 27 of the folding knife 26 (see Figure 4). The dimension 44 of the segments 41, which remain unfolded, in the fold back of the middle layer 6, further corresponds to the width of the annular grooves 13 formed in the peripheral surfaces of the first 9 and of the second folding roller 10 according to FIG. 2 , as well as the width 23 of the pockets 22

  in the lateral surfaces of the rollers 9 and 10 according to Figure 3.

  Thanks to the folding members cooperating according to the invention and shaped as just described, the layers located most inside a multilayer example, can be made so that in the area of the back of the fold, segments 42, folded longitudinally, alternate with segments 41 which remain unfolded, which considerably improves the mechanical strength, seen in the direction of orientation of the fibers,

  layers 4, 5 located furthest inside. Thanks to the improved resistance

  Mechanical strength in the direction of the fibers, the assembly elements in the form of staples placed in the unfolded segments 41, guarantee that the middle layer 4 and, possibly, other layers 5 located inside the copy , remain permanently connected to the other layers of the copy and that, when such a copy is opened, pages, in particular those located furthest inside, cannot come off.

Claims (19)

R E V E N D I C A T I ONS   1. Method for folding flat copies (1), in particular of printed products and the like, the copies (1) being composed of several   layers (4, 5) and folding operations producing open ends   tes (3, 7) and fold backs (2, 6) closed on the copies (1), characterized in that the fold back (6) of the inner layers (4, 5) of   the copy (1) with interruptions by unfolded segments (41).   2. Method according to claim 1, characterized in that the fold back   (6) remains rounded in the area of the unfolded segments (41).   3. Method according to claim 1, characterized in that the non-folded segments (41) of the fold back (6) are located in the area of   stapling positions (28.1, 28.2, 28.3).   4. Method according to claim 3, characterized in that the stapling positions (28.1, 28.2, 28.3) on the fold back (6) are arranged in function format.   5. Method according to claim 1, characterized in that the   back of fold (6) parallel to the fibers of the material of the example.   6. Method according to claim 1, characterized in that the fold back (6) is formed with non-folded segments (41) by pressing the layers   (4, 5) of the copy in a slot (11) between folding rollers (9, 10).   7. Method according to claim 1, characterized in that the formation of the back of fold (6) with unfolded segments (41), is carried out during a transverse folding operation during the transfer of the copy (1) d 'a   specimen guide cylinder to the next specimen guide cylinder.   8. Device for folding flat copies (1), in particular of   printed matter and the like, in particular for the implementation of the program   folded back according to any one of the preceding claims, the   copies (1) being composed of several layers (4, 5) and the opera-   folding operations producing open end areas (3, 7) and fold back areas (2, 6) closed on the copies (1), the fold back areas (2, 6) being formed on the copies (1) by folding members (9, 10, 26), at least one of which acts linearly on the layers (4, 5) of a multilayer folded example, characterized in that the folding members (9,, 26) have recesses (13, 22, 28) and form, on the layers (4, 5) of the specimen (1), a fold back (6) comprising folded segments (42)   longitudinally and unfolded segments (41).   9. Device according to claim 8, characterized in that the recesses (13, 22, 28) of the folding members (9, 10, 11) have a width (17,   23, 30) corresponding to the dimension (44) of the unfolded segments (41).   10. Device according to claim 8, characterized in that the depth (18, 25, 29) of the recesses (13, 22, 28) of the folding members (19, 26) creates, in the region of the back of the fold (6 ), spaces (8) surrounding assembly elements.   11. Device according to claim 8, characterized in that the hollows   (22,23,28) folding members (19,26) are arranged according to the format.   12. Device according to claim 11, characterized in that recesses (28.1, 28.3) for staple positions (38, 40) of a first folded format are placed at a distance A from one end of the gross length (31) layers (4, 5) of the item.   13. Device according to claim 11, characterized in that a recess (28.2) for a stapling position (39) of a second folded format is placed at a distance B, relative to one end of the gross length ( 31) of the layers (4, 5) of the copy, which roughly corresponds to the half that length.   14. Device according to claim 8, characterized in that the hollow (13) is a circumferential annular groove formed in rollers   folders (9, 10) defining a folding slot (11).   15. Device according to claim 8, characterized in that the recesses (22) are pockets formed in the lateral surfaces (12) of rollers folders (9, 10).   16. Device according to claim 15, characterized in that the pockets (22) extend over a sector in an arc of a circle of the lateral surface (12) folding rollers (9, 10).   17. Device according to claim 8, characterized in that the recesses (28) are arranged in the region of the folding edge (27) of a folding knife   (26) forming part of a second longitudinal folding device.   18. Folded copy (1), in particular of a printed or ana-   log, composed of several layers (4, 5) and having open ends (3, 7) and closed areas on the back of fold (2, 6), obtained in particular by the method and / or the device according to any of   previous claims, characterized in that the fold back (6) of   layers (4, 5) located inside the copy, includes segments   unfolded (41) having a round (8) and segments (42) folded longitu-   ultimately. 19. Folder for folding flat copies, in particular of printed products, in particular applying the method and / or the device   according to any one of claims 1 to 17, the copies (1) being   composed of several layers (4, 5) and of the folding operations produced   sant open ends (3, 7) and fold backs (2, 6) closed on the copies (1), the fold back areas (2, 6) of the copies (1) being formed by folding members (9, 10, 26) at least one of which acts linearly on the flat layers (4, 5) of an example, characterized in that the folding members (9, 10, 26) have recesses (13, 22, 28) and form, on the layers (4, 5) of the example (1), a fold back (6) comprising segments (42) folded longitudinally and segments unfolded (41).