Abstract
An apparatus for folding sheets or sheet stacks, including at least two folding/transport rollers, transport device and knife, the transport device defining transport plane E for sheets or sheet stacks fed in transport direction R, knife being movable substantially perpendicularly to and through transport plane E, folding/transport rollers being arranged above transport plane E, oppositely on both sides of knife, axis of rotation A of folding/transport rollers extending substantially perpendicularly to transport plane E, and at least two folding/transport rollers each having, at their end facing toward transport plane E, rounded portion, such that narrowing gap S is formed between the at least two folding/transport rollers, into which gap sheets or sheet stacks can be introduced by means of knife so as to be folded there and at same time conveyed away in transport direction R, and to corresponding method.
Claims
1. An apparatus for folding sheets or sheet stacks, comprising at least two folding/transport rollers, a transport device and a knife, the transport device defining a transport plane E for sheets or sheet stacks fed in a transport direction R, the knife being movable substantially perpendicularly to and through the transport plane E, the folding/transport rollers being arranged above the transport plane E, oppositely on both sides of the knife, an axis of rotation A of the folding/transport rollers extending substantially perpendicularly to the transport plane E, and the at least two folding/transport rollers each having, at their end facing toward the transport plane E, a rounded portion, such that a narrowing gap S is formed between the at least two folding/transport rollers, into said gap the sheets or sheet stacks can be introduced by means of the knife so as to be folded there and at the same time conveyed away in the transport direction R and wherein the knife is configured to carry out a horizontal movement during the folding process, the apparatus further comprising at least two drive rollers configured to rotate about an axis of rotation extending substantially perpendicular to the axis of rotation A of the folding/transport rollers and substantially perpendicular to the transport plane E, wherein the knife is hingedly coupled to the at least two drive rollers such that rotation of the driver rollers moves the knife through a circular path, and a component of the circular path includes the horizontal movement during the folding process.
2. The apparatus as claimed in claim 1, wherein the rounded portions of the folding/transport rollers have a spherical washer-shaped embodiment.
3. The apparatus as claimed in claim 1, wherein the folding/transport rollers are spring-mounted transversely to the transport direction R.
4. The apparatus as claimed in claim 1, wherein the knife is hinged to at least two drive rollers.
5. The apparatus as claimed in claim 4, wherein the drive rollers are driven at constant rotational speed during the folding process.
6. The apparatus as claimed in claim 1, wherein a depth of penetration X of the knife into the gap S formed between the folding/transport rollers is approximately 5 to 10 mm.
7. The apparatus as claimed in claim 1, wherein the transport device is embodied in form of two conveyor belts running parallel to one another.
8. The apparatus as claimed in in claim 1, wherein a glue head is arranged downstream of the folding/transport rollers.
9. The apparatus as claimed in claim 1, wherein a light barrier is arranged upstream of the folding/transport rollers for detection of a rear edge of a sheet or a sheet stack.
10. The apparatus as claimed in claim 9, wherein the detection of the rear edge of a sheet or a sheet stack triggers a movement of the knife.
Description
(1) The accompanying drawings serve to illustrate the invention and in this respect constitute merely preferred embodiments of the present invention.
(2) In the drawings:
(3) FIG. 1a shows a schematic perspective view of the apparatus according to the invention for folding sheets or sheet stacks;
(4) FIG. 1b shows a schematic side view of the apparatus according to the invention the folding sheets or sheet stacks;
(5) FIG. 1c shows a schematic front view of the apparatus according to the invention for folding sheets or sheet stacks;
(6) FIG. 2a shows a schematic perspective view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a first position;
(7) FIG. 2b shows a schematic side view of a detail of the apparatus according to the invention the folding sheets or sheet stacks in a first position;
(8) FIG. 2c shows a schematic front view of a detail of the apparatus according to the invention the folding sheets or sheet stacks in a first position;
(9) FIG. 3a shows a schematic perspective view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a second position;
(10) FIG. 3b shows a schematic side view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a second position;
(11) FIG. 3c shows a schematic front view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a second position;
(12) FIG. 4a shows a schematic perspective view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a third position;
(13) FIG. 4b shows a schematic side view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a third position;
(14) FIG. 4c shows a schematic front view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a third position;
(15) FIG. 5a shows a schematic perspective view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a fourth position;
(16) FIG. 5b shows a schematic side view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a fourth position; and
(17) FIG. 5c shows a schematic front view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a fourth position;
(18) FIG. 6a shows a schematic perspective view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a fifth position;
(19) FIG. 6b shows a schematic side view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a fifth position;
(20) FIG. 6c shows a schematic front view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a fifth position;
(21) FIG. 7 shows a schematic perspective view of a processing line for the method according to the invention for producing a newspaper product;
(22) FIG. 8a shows an exemplary paper web for the method according to the invention in a processing line according to FIG. 7;
(23) FIG. 8b shows an exemplary paper roll for the method according to the invention in a processing line according to FIG. 7;
(24) FIG. 9 shows a separated sheet for a first sub-product and a separated sheet for a second sub-product;
(25) FIG. 10 shows a stack for a first sub-product and a stack for a second sub-product;
(26) FIG. 11 shows a transversely folded stack for a second sub-product;
(27) FIG. 12a shows views of a first sub-product from different perspectives;
(28) FIG. 12b shows views of a second sub-product from different perspectives;
(29) FIG. 13 shows views of a finished newspaper product from different perspectives;
(30) FIG. 14 shows a number of finished newspaper products when conveyed away in stream delivery.
(31) FIG. 1a shows a schematic, perspective view of the apparatus according to the invention for folding sheets or sheet stacks, but here not yet with a sheet or a sheet stack.
(32) The feed rollers for the sheets or sheet stack are designated by reference sign 8. A weakening apparatus for the incoming sheets or sheet stack is provided above the feed rollers 8 and serves to weaken the paper before the folding and thus make the paper easier to fold. Here, this may be on the one hand an apparatus for forming a groove along the desired fold line (scoring) or may be a perforating apparatus. It is additionally also possible for a line of water droplets to be sprayed onto the paper by means of the weakening apparatus 11 in order to temporarily weaken the paper. However, it is also possible for the weakening of the paper to be carried out suitably during the folding process. As a result of the weakening it is possible to very efficiently prevent a skewed fold, which leads to a significant increase of the quality of the finished product.
(33) A light barrier 7 is also provided downstream of the weakening apparatus 11, but still in the region of the feed rollers 8. The light barrier 7 serves to detect the rear edge of a sheet or a sheet stack and triggers a movement of the knife 2 (in this respect the light barrier 7 is of course connected to a corresponding control unit, which is not shown here for reasons of simplicity).
(34) The knife 2 is connected via the connection piece 9 to each of the drive rollers 5 (generally belt pulleys) or is hinged thereto. The drive rollers 5 are driven in the direction shown by the respective arrows (i.e. in the present case in an anti-clockwise direction).
(35) The knife 2 is arranged between two conveyor belts 3a and 3b of a transport device 3, such that it can engage substantially centrally with the fed sheets. A number of pairs of mutually opposed folding/transport rollers 1 are arranged above the transport device 3 and serve to fold and simultaneously convey the sheets or sheet stack. In a preferred embodiment the conveyor belts 3a, 3b may also extend upstream beyond the folding/transport rollers 1 and where appropriate may thus take over the function of the feed rollers 8 wholly or at least in part.
(36) A pair of pressing rollers 19 is provided downstream of the folding/transport rollers 1 and serves to again press the previously formed fold together or against itself and thus contributes to an increase of the quality of the fold. A glue head 6 is arranged downstream of the pressing rollers 19, by means of which glue head a line of glue can be applied to the fold edge of the respective sheet or sheet s tack.
(37) Lastly, a pair of holding rollers 10 is also provided downstream of the glue head 6. The holding rollers 10 serve to prevent a dipping of the folded sheet or sheet stack during the gluing. It is thus ensured that the folded sheet or sheet stack comes out of the apparatus with a straight alignment.
(38) In FIG. 1b like reference signs designate the same components, and this is also true for the remaining description of the figures. In this side view the transport plane E for the sheets or sheet stack to be processed can be seen in particular. The transport plane E is defined here substantially by the surface of the conveyor belts 3a, 3b of the transport device 3 and where appropriate also by the virtual upper side of the feed rollers 8. The axis of rotation A of the folding/transport rollers 1 extends perpendicularly to the transport plane E. The axis of rotation A is indicated here merely by way of example for one of the folding/transport rollers, however it extends in the same way in the case of the rest of the folding/transport rollers 1. Again by way of example, the folding/transport roller 1 positioned farthest to the left in the transport direction R is illustrated in a divided manner, more specifically divided into its rounded portion 1a and the cylindrical portion 1b (this embodiment will be explained further below in greater detail). It can additionally be clearly seen that the glue from the glue head 6 is applied once the sheet or sheet stack has passed through the pressing rollers 19, but before entry into the holding rollers 10.
(39) In the front illustration according to FIG. 1c, it can be seen that the knife 2 hinged to the drive rollers 5 via the connection pieces 9 is arranged exactly centrally between the conveyor belts 3a and 3b and that the respective roller pairs, i.e. the holding rollers 10, the pressing rollers 19 and the folding/transport rollers 1, are arranged in each case oppositely on both sides of the knife 2. The glue head outlet 6a is arranged here such that the glue can pass precisely onto the fold of the sheets or sheet stack formed by the knife. The lower half of the feed rollers can also be seen beneath the conveyor belts 3a and 3b.
(40) FIG. 2a shows a schematic, perspective view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a first position, in which a sheet or sheet stack 4 is fed by means of the feed rollers 8 to the transport device 3 or the two conveyor belts 3a, 3b. The rear edge 14 of the sheet or sheet stack 4 here has not yet passed the light barrier 7 shown in FIG. 1a; the front edge 13 is transferred first to the conveyor belts 3a, 3b. The knife 2 is thus in its starting position. The folding/transport rollers 1 are therefore also not yet engaged with the sheet or sheet stack 4. The connection pieces 9 hinged to the drive rollers 5 are located here in their right, middle position.
(41) In FIG. 2b the geometric relationship between the transport direction R, the transport plane E and the axis of rotation A of the folding/transport rollers 1 is illustrated: the axis of rotation A is substantially at right angles to the transport plane E and to the transport direction R.
(42) In FIG. 2c it can be seen that the upper edge or upper side of the knife 2 is arranged exactly below the underside of the incoming sheet or sheet stack 4. On the one hand the feed of the incoming sheet or sheet stack 4 therefore is not blocked, and on the other hand the knife 2 can come directly into engagement with the sheet or sheet stack 4 upon a corresponding signal from the light barrier 7 or the associated control unit.
(43) A gap S is formed between the folding/transport rollers 1 via their rounded portions 1a and their cylindrical portions 1b, which gap narrows increasingly as viewed from bottom to top. The inner sides of the two folding/transport rollers illustrated in cross section form accordingly an asymptotic arrangement. The rounded portions 1a of the folding/transport rollers are spherical washer-shaped, such that they have a flattened region 1c on their underside. The flattened region 1c serves to prevent the knife 2 from having to penetrate too deeply between the folding/transport rollers 1 during operation. The direction of rotation of the axis of rotation A of the two folding/transport rollers 1 shown is opposite that specified by the two arrows.
(44) FIG. 3a shows a schematic, perspective view of a detail of the apparatus according to the invention for folding sheets or sheet stacks in a second position, in which the sheet or sheet stack 4 already rests completely on the conveying belts 3a, 3b of the transport device 3 (see also FIG. 3b). The rear edge 14 of the sheet or sheet stack 4 has thus passed the light barrier, such that the triggering of a movement of the knife 2 is immediately imminent, but has not yet occurred. The knife 2 bears almost directly against the underside of the sheet or sheet stack 4 (see FIG. 3c) and is ready to move this out of the transport plane E.
(45) Schematic detail views of an apparatus according to the invention for folding sheets or sheet stacks in a third position, in which the knife 2 has now been moved, are now illustrated in FIGS. 4a to 4c. The drive rollers 5 or the connection pieces 9 hinged thereto have been moved into the uppermost position through a circular arc of 90 in the direction of rotation specified by the arrows, such that the knife 2 has moved or introduced the sheet or sheet stack 4 into the gap S between the folding/transport rollers 1. The folding/transport rollers 1 are preferably spring-mounted here, as specified by means of the double-headed arrow in FIG. 4c, such that they can move horizontally away from one another when the knife 2 together with the sheet or sheet stack 4 penetrates the gap S, or can move together again when the knife 2 and/or the sheet or sheet stack 4 are/is no longer located in the gap S.
(46) The depth of penetration of the knife 2 into the gap S is designated by X (see FIG. 4c) and is generally measured from the underside or flattened region 1c of the folding/transport rollers 1 to the upper side or upper edge of the knife 2. The knife 2 here has reached its highest position between the folding/transport rollers 1, the upper side of the knife 2 protruding into the region between the cylindrical portions 1b of the folding/transport rollers 1, i.e. beyond the rounded portions 1a.
(47) FIGS. 5a to 5c show schematic detail views of the apparatus according to the invention for folding sheets or sheet stacks in a fourth position, in which the knife 2 is no longer engaged with the sheet or sheet stack 4. The drive rollers 5 or the connection pieces 9 hinged thereto have continued to move in the arrow direction through a further circular arc of 90 and are now located in their left middle position. The knife 2 is thus again directly beneath the transport plane E. The sheet or sheet stack 4 has been moved slightly further in the transport direction R by the folding/transport rollers 1 compared with the third position according to FIGS. 4a to 4c and at the same time has been folded, the fold 12 of the sheet or sheet stack 4 extending parallel to the transport plane E.
(48) FIGS. 6a to 6c show lastly schematic detail views of the apparatus according to the invention for folding sheets or sheet stacks in a fifth position, in which the sheet or sheet stack 4 has been conveyed further in the transport direction R and at the same time has been folded, such that it is now engaged with the pressing rollers 19 and where appropriate the glue head 6 and the holding rollers 10, in accordance with FIGS. 1a to 1c. The fold 12 still runs parallel to the transport plane E. A further sheet or sheet stack 4 has already been transported by the feed rollers 8 in the direction of the conveyor belts 3a and 3b.
(49) The drive rollers or belt pulleys 5 have continued to move through a further circular arc of 90 (see arrows), such that the hinged connection piece 9 is in its lowermost position. The knife 2 has here likewise reached its lowermost position accordingly. In FIG. 6c it can be seen that the lower edge of the connection piece 9 is practically flush with the underside of the drive rollers or belt pulleys 5.
(50) The knife 2 then passes from this position back into its starting position according to FIGS. 2a to 2c via a further movement along a circular arc of 90, in which starting position the front edge 13 of the next sheet or sheet stack 4 has arrived at the transport device 3 and the previous sheet or sheet stack 4 has in any case left the folding/transport rollers 1.
(51) On account of the illustrated cooperation between the individual components of the apparatus according to the invention, the sheets or sheet stacks 4 are always transported in the same transport direction R, whereby high processing speeds and short clock cycles can be achieved.
(52) FIG. 7 shows a schematic perspective view of a processing line for the method according to the invention for producing a newspaper product from at least one first and one second sub-product. The processing line 40 is composed here from the following components (as considered from right to left in the transport direction):
(53) At the start of the processing line 40 there is an unwinder 41 for the (endless) paper roll 23. From here, the unwound paper web is transferred to the printer 42, which is routinely formed as a digital printing machine. Here, the paper web is printed with corresponding sheets of different size. The printer 42 may be adjoined by a vacuum box 43, which serves as a buffer for speed compensation.
(54) A transverse cutter 44 is arranged downstream of the vacuum box 43 and ensures the separation of the sheets. The transverse cutter 44 is adjoined by a collator 45 (generally a drum collator), on which a stack is formed from the corresponding sheets. A gluing of the sheets forming the stack may also be carried out on the collator 45.
(55) The stacks are then transferred from the collator 45 to a folding module 46, which is divided into a feed 46a, a transverse folding apparatus 46b (optional) and a longitudinal folding apparatus possibly having a saddle-like apparatus (in a module). The feed 46a should be sufficiently long (generally a number of sheet lengths) to be able to brake the incoming stack where appropriate. The folding module 46 is also joined by a conveying-away arrangement 47 for transporting away the finished newspaper products 30.
(56) A paper web 22 is now shown schematically in FIG. 8, onto which sheets 4, 4 having a different format have already been printed. The two sheets 4 each have a length L.sub.1 and the sheet 4 has a length L.sub.2, the length L.sub.2 being approximately twice as great as the length L.sub.1 of the sheets 4. The width B of the paper web 22 is the same in each case.
(57) The paper web 22 is periodically unwound from a (endless) paper roll 23, as shown in FIG. 8b. The two sheets 4 and the approximately twice as long sheet 4 can also be seen. It is, however, also possible for the sheets 4 and 4 to be fed individually.
(58) In FIG. 9 a separated sheet 4 and a separated sheet 4 are now shown. The separation is generally performed in the transverse cutter 44, as already presented above.
(59) FIG. 10 illustrates a stack 24 formed from sheets 4 and a stack 24 formed from sheets 4. The stack 24 here comprises five sheets 4 and in the middle has a fold line 25 illustrated in a dashed manner. The stack 24 in the present case comprises three sheets 4 and has a fold line 26 and also a fold line 27. The individual stacks 24 and 24 are collated on the collator 45 according to FIG. 7.
(60) A stack 24 formed from three sheets 4 and folded about a transverse fold line 26 is illustrated on the basis of FIG. 11. The fold edge 26a was formed during the folding, and the fold line 27, which has not yet been folded, can also be seen. In the method according to the invention this step constitutes an optional intermediate step.
(61) In FIG. 12a views of a first sub-product 31 of a newspaper product are now shown from three different perspectives. The first sub-product 31 is formed by the longitudinal folding of a stack 24 formed from five sheets 4 along the longitudinal fold line 25. The fold edge 25a is formed during this process.
(62) FIG. 12b shows corresponding views of a second sub-product 32. The second sub-product 32 is formed by folding the stack 24 shown in FIG. 11 along the fold line 27. In doing so, the fold edge 27a is formed, which divides the fold edge 26a in the middle. The corresponding folding steps are carried out on the folding module 46 according to FIG. 7.
(63) FIG. 13 schematically illustrates the sub-products 32 and 31 collated in a saddle-shaped manner to form a finished newspaper product 30. In the present case a sub-product 31 (i.e. formed from sheets 4) is inserted by way of example into four sub-products 32 (i.e. formed from sheets 4). The finished newspaper product 30 may of course also assume any other arbitrary form, at least the outermost sub-product, however, being routinely a second sub-product 32. The folded sub-products 31, 32 may additionally also be glued to one another during the collation.
(64) The optional method steps possibly to be performed and the time at which they are to be performed is preferably set by means of a control unit (not illustrated in FIG. 7 for reasons of simplicity): transverse fold yes/no, glue application when stacking the as yet unfolded sheets yes/no, glue application when collating the folded sub-products yes/no, weakening of the fold lines yes/no, etc.
(65) FIG. 14 lastly shows five finished newspaper products 30 as conveyed away in the preferred stream delivery, in which the individual newspaper products 30 lie on one another in the manner of roofing tiles. The finished newspaper products 30, however, may also be conveyed away individually or as a stack. The products are conveyed away by means of the conveying-away arrangement 47, as illustrated schematically in FIG. 7.
LIST OF REFERENCE SIGNS
(66) 1 folding/transport rollers 1a rounded portion 1b cylindrical portion 1c flattened region 2 knife 3 transport device 3a conveyor belt 3b conveyor belt 4 sheets/sheet stack 4 sheets 4 sheets 5 belt pulleys/drive rollers 6 glue head 6a glue head outlet 7 light barrier 8 feed rollers 9 connection piece 10 holding rollers 11 weakening apparatus 12 fold 13 front edge 14 rear edge 19 pressing rollers 22 paper web 23 paper roll (printed) 24 stack 24 stack 25 fold line 25a fold edge 26 fold line 26a fold edge 27 fold line 27a fold edge 30 newspaper product 31 first sub-product 32 second sub-product 40 processing line 41 unwinder 42 printer 43 vacuum box 44 transverse cutter 45 collator 46 folding module 46a feed 46b transverse folding apparatus 46c longitudinal folding apparatus 47 conveying-away arrangement A axis of rotation E transport plane L.sub.1 length L.sub.2 length R transport direction S gap X depth of penetration circular arc
