A machine and method for producing stacks of napkins

Abstract

A machine and method (1000) for producing, from strips (N1, N2) of stacks (P) of napkins. The machine comprises at least a supply line (100, 200) of sheet articles (S) identical to one another and folded on at least a fold line (Sp, Sp', Sp") and forming means (10), for forming stacks (P) of sheet articles (S) folded in a V shape, which comprise a first roller (1 ) and a second roller (2) that rotate at a same tangential velocity (w1, w2) in opposite directions, with an offset orientation with respect to one another by half a sheet article (S), and which comprise means and respective retaining means (15, 25) of sheet articles (S) so as to pull the proximal ends (Se, Se') of two successive sheet articles (S) together with the flanked part of the sheet article (S) on the other first roller or second roller (1, 2) until forming a central fold line (Scentr). A stack (P) of napkins.

Description

[0001] A MACHINE AND METHOD FOR PRODUCING STACKS OF NAPKINS.

[0002] FIELD OF THE INVENTION

[0003] The present invention concerns the technical sector relating to machines and procedures for producing stacks of folded articles in sheet form from strips, or reels, generally obtained starting from reels of paper, and relates to the technical sector of those folded articles in sheet form. In greater detail, the invention relates to a machine or a method for producing, from strips, stacks of sheet articles folded in a V shape. Articles in sheet form folded in a V shape are commonly known as single fold articles and comprise a central fold line between two ends. In the present description, by stack of sheet articles folded in a V shape is meant a group of articles folded in a V shape, superposed on one another, with each sheet being folded on a central fold line, which is central between the two ends of the V. To obtain an article commonly known as a napkin, these articles in sheet form folded in a V shape must also be folded on at least a fold line which is orthogonal to the central fold line and which extends between two ends of the V. In other words, each superposed napkin has on one side a central fold line and on the other side of the stack the two ends, and has at least a fold line between the two ends in the direction that joins the sides of the stack. Figures 1 and 5 illustrate an example of a stack of sheet articles folded in a V shape, as well as folded on at least a fold line orthogonal to the central fold line, of known type, while figure 3 is a schematic view of the same stack.

[0004] DESCRIPTION OF THE PRIOR ART

[0005] The use is known of machines for producing stacks of napkins from continuous strips folded transversally, on two opposite sides, and which are cut centrally with respect to the two sides so as to obtain a first stack of napkins, entirely alike to that of figure 3, and a second stack of napkins, specular with respect to that of figure 3.

[0006] DE2853741A1 illustrates a machine for producing groups of articles in sheet form folded in a V shape starting from a reel. The reel is cut longitudinally into strips and each strip is then longitudinally folded by folding means, generally known as fold line triangles. Each strip thus crosses two folding rollers so as to be folded and then cut, as illustrated in the foregoing. A further example of a machine for producing stacks of articles in sheet form folded in a V shape is described in W02022070087A1 .

[0007] The expert in the field knows numerous types of longitudinal folds of the strip that are realisable with successive stations of folding means that enable obtaining variants of sheet articles folded in a V shape. Examples of sheet articles folded in a V shape with at least a fold line orthogonal to the central fold line are illustrated in figures from 22 to 39.

[0008] It is also known how the sheet and the strip can comprise a single veil or several veils, including of materials that are different to one another.

[0009] Although, in the machine of DE2853741A1 , it is possible to subdivide the reel into several strips, the folding rollers that limit the production velocity operate on strips set parallel to one another. This means that the productivity of the machine increases only with an increase in the overall size of the equipment.

[0010] Further, in DE2853741A1 , the cut takes place on overlapped layers of strip with the risk of obtaining articles with imperfect cuts.

[0011] As illustrated in figures 1 , 3, and 5, the stacks of sheet articles folded in a V shape by machines of known type, such as the one illustrated in DE2853741A1 , have all the central fold lines on a same side of the stack, increasing the overall thickness of the stack on the side of the central fold lines, i.e. with a thickening on the side opposite the side with the ends of the V.

[0012] Imperfect cuts, such as the central fold lines on the same side, make the packaging and / or the use of the stacks of sheet articles folded in a V shape more difficult.

[0013] The present invention intends to obviate one or more drawbacks of the solutions of the prior art.

[0014] SUMMARY OF THE INVENTION

[0015] A first aim of the present invention is to provide a machine and a method for producing stacks of napkins with good productivity and with quality napkins, in particular with cuts that are well-positioned and precise.

[0016] A further aim of some embodiments is to realise stacks of napkins with uniform sizes.

[0017] A further aim is to limit the dimensions of encumbrance in relation to the productivity and / or maximising the productivity given a same width of the machine. These and other aims, which will be obvious to the expert in the sector from a reading of the following text, are attained by means of a machine or a method for producing, from strips, stacks of sheet articles folded in a V shape, on a central fold line between the two ends of the V, as well as folded on at least a fold line, orthogonal to the central fold line, which extends between the two ends of the V.

[0018] In accordance with the teachings of the present document, the machine comprises at least a supply line of sheet articles identical to one another and folded on at least a fold line and forming means for forming stacks of sheet articles folded in a V shape. The at least a supply line comprises a second strip supply line, second folding means, for longitudinally folding a strip, and cutting means, for cutting sheet articles from a longitudinally folded strip.

[0019] The forming means comprise a first roller which has a lateral surface for receiving articles in sheet form and which rotates with respect to a first rotation axis, a second roller which has a respective lateral surface for receiving sheet articles and which rotates with respect to a second rotation axis which is parallel to the first rotation axis and which insists together with the first rotation axis on a join plane, support means, for supporting a stack of sheet articles folded in a V shape beneath the first roller and the second roller, first folding elements which, at a first folding area, move the sheet articles from the lateral surface towards the support means so as to form a central fold line and second folding elements which, at a relative second folding area, move the sheet articles from the respective lateral surface towards the support means so as to form a central fold line.

[0020] The first roller comprises retaining means of the sheet articles which are arranged in such a way as to divide the lateral surface into two or more parts which define angles of circumference that are identical to one another, each for retaining a sheet article and each having two ends and an equidistant part which is equidistant from the two ends.

[0021] The retaining means of the first roller are arranged so as to retain a sheet article at least at each of the two ends of each of the two or more parts.

[0022] The second roller comprises retaining means of the sheet articles which are arranged in such a way as to divide the lateral surface into two or more portions which define angles of circumference that are identical to one another, each for retaining a sheet article and each having respective two ends and an equidistant part which is equidistant from the respective two ends.

[0023] The respective retaining means of the second roller are arranged so as to retain a sheet article at least at each of the respective two ends of each of the two or more portions.

[0024] The at least a supply line of sheet articles feeds, with a sheet article, each of the two or more parts and each of the two or more portions.

[0025] The first rotation axis and the second rotation axis are moved away from one another in such a way that, at the join plane, two flanked sheet articles can be interposed between the lateral surface of the first roller and the respective lateral surface of the second roller, the retaining means of the first roller can act on the sheet article interposed more closely to the respective lateral surface of the second roller and the respective retaining means of the first roller can act on the sheet article interposed more closely to the respective lateral surface of the second roller.

[0026] The first roller and the second roller rotate at a same tangential velocity, with opposite rotation directions to one another.

[0027] The first roller is orientated with respect to the first rotation axis and the second roller is orientated with respect to the second rotation axis so that during the rotation thereof an end crosses the join plane together with a respective equidistant part facing towards the first roller and, vice versa, a respective end crosses the join plane together with a respective equidistant part facing towards the second roller.

[0028] The retaining means of the first roller are arranged and / or configured in such a way as to avoid retaining in the equidistant part, at least when the equidistant part is facing towards the second roller and crosses the join plane, so that the central part of a sheet article in contact with the lateral surface is not aspirated by the retaining means and the respective retaining means draw or receive the central part.

[0029] The respective retaining means of the second roller are arranged and / or configured in such a way as to avoid retaining in the equidistant part, at least when the equidistant part is facing towards the first roller and crosses the join plane, so that the central part of a sheet article in contact with the respective lateral surface is not aspirated by the respective retaining means and the respective retaining means draw or receive the central part.

[0030] The retaining means of the first roller are configured to retain at least when each of the two ends moves along a first portion between the join plane and the first folding area so as to retain ends of sheet articles received by successive parts of the two or more parts and a central part of a sheet article received by a portion of the two or more portions and the respective retaining means of the second roller are configured to retain at least when each of the respective two ends moves along a respective first portion between the join plane and the second folding area, so as to retain ends of sheet articles received by successive portions of the two or more portions and a central part of a sheet article received by a part of the two or more parts.

[0031] In accordance with the teachings of the present document, the method comprises steps of steps of:

[0032] - providing at least a strip;

[0033] - longitudinally folding the at least a strip so as to form one or more longitudinal folds;

[0034] - transversally cutting the at least a longitudinally folded strip so as to obtain sheet articles that are identical to one another having a length between two ends and at least a fold line between the two ends;

[0035] - flanking sheet articles between them so as to create a first succession of sheet articles and a second succession of sheet articles flanked and staggered by half a length;

[0036] - folding the flanked sheet articles in a V shape, by pulling the proximal ends of two successive sheet articles of the first succession together with the part, of the sheet article of the second succession, flanked to the same ends, on the side of the first succession until forming a central fold line and by pulling the proximal ends of two successive sheet articles of the second succession together with the part, of the sheet article of the first succession, flanked to the same ends on the side of the second succession until forming a central fold line;

[0037] - forming a stack of sheet articles folded in a V shape one above the other.

[0038] BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Specific embodiments of the invention will be described in the following part of the present description, according to what is set down in the claims and with the aid of the accompanying figures, in which: figure 1 is an axonometric view of a stack of sheet articles folded in a V shape, on a central fold line between the two ends of the V, as well as folded on at least a fold line, orthogonal to the central fold line, which extends between the two ends of the V of the prior art; figure 2 is an embodiment of a stack of napkins obtained with the machine or the method according to the invention; figure 3 is a diagram illustrating the arrangement of the napkins of the stack of figure 1 ; figure 4 is a representative illustration of the arrangement of the sheet articles folded in a V shape, on a central fold line between the two ends of the V, as well as folded on at least a fold line, orthogonal to the central fold line, which extends between the two ends of the V of the stack of figure 2; figure 5 is an axonometric view of the stack of figure 1 from a different point of view; figure 6 is an axonometric view of a further embodiment of a stack of napkins obtained with the machine or the method according to the invention; figure 7 is a perspective view of the stack of figure 6; figure 8 is a perspective view of the stack of figure 2; figure 9 is an axonometric view of a portion of an embodiment of a machine for producing napkins according to the invention; figure 10 is a representative diagram of the functioning of the machine and method according to the invention; figure 11 schematically shows, with the aid of a larger scale, the sequences of sheet articles in an embodiment of a machine for producing napkins according to the invention, with some elements removed to facilitate the understanding of the figure; figure 12 is an axonometric view of a portion of an embodiment of a machine for producing napkins according to the invention, consistent with the representative diagram of figure 11 ; figure 13 is a larger-scale view of the previous figure in which there is a cut of a sheet coming from the reel and the folding of the strips obtained; figure 14 is a section view of the central part of the machine of figure 12, with the supply and the unloading schematically summarised respectively above and below; figure 15 is a view in larger scale of figure 14; figure 16 is a section view of an operating step following that of figure 14; figure 17 is a view in larger scale of figure 16; figure 18 is a section view of a successive operating step following that of figure 16; figure 19 is a view in larger scale of figure 18; figure 20 is a section view of a central part alternative to that of figure 14 which might operate in the embodiment of figure 12 or in another embodiment of the machine of the invention; figure 21 is a section view of another central part alternative to that of figure 14 and that of figure 20 which might operate in the embodiment of figure 12 or in another embodiment of the machine according to the invention; figures from 22 to 39 show examples of sheet articles folded in a V shape, on a central fold line between the two ends of the V, as well as folded on at least a fold line, orthogonal to the central fold line (Scentr), which extends between the two ends of the V.

[0040] DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0041] With reference to the appended figures, reference numeral 1000 denotes a machine for producing, from strips (N1 , N2), generally made of paper, stacks (P) of sheet articles (S) folded in a V shape, on a central fold line (Scentr) between the two ends (Se, Se’) of the V, as well as folded on at least a fold line (Sp, Sp’, Sp”), orthogonal to the central fold line, which extends between the two ends (Se, Se’) of the V. The references are included to facilitate understanding of the invention but are not intended to limit the scope of protection thereof.

[0042] An embodiment of the machine (1000) comprises at least a supply line (100, 200) of sheet articles (S) identical to one another and folded on at least a fold line (Sp, Sp’, Sp”) and forming means (10), for forming stacks (P) of sheet articles (S) folded in a V shape.

[0043] The at least a supply line (100, 200) comprises:

[0044] - a strip supply line (110);

[0045] - folding means (120), for longitudinally folding a strip (N1 , N2); and

[0046] - cutting means (130), for cutting sheet articles (S) from a longitudinally folded strip (N1 p, N2p).

[0047] The forming means (10) comprise:

[0048] - a first roller (1 ) which has a lateral surface (11 ) for receiving articles in sheet form (S) and which rotates with respect to a first rotation axis (X1 );

[0049] - a second roller (2) which has a respective lateral surface (21 ) for receiving sheet articles (S) and which rotates with respect to a second rotation axis (X2) which is parallel to the first rotation axis (X1 ) and which insists together with the first rotation axis (X1 ) on a join plane (U);

[0050] - support means (5), for supporting a stack (P) of sheet articles (S) folded in a V shape beneath the first roller (1 ) and the second roller (2);

[0051] - first folding elements (3) which, at a first folding area (P1 ), move the sheet articles (S) from the lateral surface (11 ) towards the support means (5) so as to form a central fold line (Scentr); and

[0052] - second folding elements (4) which, at a second folding area (P2), move the sheet articles (S) from the respective lateral surface (21 ) towards the support means (5) so as to form a central fold line (Scentr).

[0053] The first roller (1 ) comprises retaining means (15) of sheet articles (S) which are arranged in such a way as to divide the lateral surface (11 ) into two or more parts (11 a, 11 b, 11 c, 11 d), in the technical field known as fold areas, which define angles of circumference (alfa) that are identical to one another.

[0054] Each part of the two or more parts 11 a, 11 b, 11 c, 1 1 d) is configured so as to retain a sheet article (S) and has two ends (12a, 13a, 12b, 13b, 12c, 13c) and an equidistant part (14a, 14b, 14c) which is equidistant with respect to the two ends (12a, 13a, 12b, 13b, 12c, 13c).

[0055] The retaining means (15) are arranged so as to retain a sheet article (S) at least at each of the two ends (12a, 13a, 12b, 13b, 12c, 13c) of each of the two or more parts (11 a, 11 b, 11 c, 11 d).

[0056] The second roller (2) comprises respective retaining means (25) of sheet articles (S) which are arranged in such a way as to divide the respective lateral surface (21 ) into two or more portions (21a, 21 b, 21 c, 21 d), in the technical language known as fold areas) which define angles of circumference (alfa) that are identical to one another.

[0057] Each portion of the two or more portions (21 a, 21 b, 21 c, 21 d) is configured for retaining a sheet article (S) and has two respective ends (22a, 23a, 22b, 23b, 22c, 23c) and a respective equidistant part (24a, 24b, 24c) which is equidistant from the two respective ends (22a, 23a, 22b, 23b, 22c, 23c).

[0058] The respective retaining means (25) are arranged so as to retain a sheet article (S) at least at each of the two respective ends (22a, 23a, 22b, 23b, 22c, 23c) of each of the two or more portions (21 a, 21 b, 21 c, 21 d).

[0059] The at least a supply line (100, 200) of sheet articles (S) feeds, with a sheet article (S), each of the two or more parts (11a, 11 b, 11c, 11d) and each of the two or more portions (21a, 21b, 21c, 21 d).

[0060] The first rotation axis (X1 ) and the second rotation axis (X2) are moved away from one another in such a way that, at the join plane (U):

[0061] - two flanked sheet articles (S) can be interposed between the lateral surface (11 ) and the respective lateral surface (21 );

[0062] - the retaining means (15) can act on the sheet article (S) interposed most proximal to the respective lateral surface (21 );

[0063] - the retaining means (25) can act on the sheet article (S) interposed most proximal to the respective lateral surface (11 ).

[0064] The first roller (1 ) and the second roller (2) rotate at a same tangential velocity (w1 , w2), with opposite rotation directions to one another.

[0065] The first roller (1 ) is orientated with respect to the first rotation axis (X1 ) and the second roller (2) is orientated with respect to the second rotation axis (X2) in such a way that during the rotation thereof:

[0066] - an end (12a, 13a, 12b, 13b, 12c, 13c) crosses the join plane (U) together with a respective equidistant part (24a, 24b, 24c) facing towards the first roller (1 ); and

[0067] - a respective ends (22a, 23a, 22b, 23b, 22c, 23c) crosses the join plane (U) together with a respective equidistant part (14a, 14b, 14c) facing towards the second roller (2).

[0068] The retaining means (15) are arranged and / or configured in such a way as to avoid retaining in the equidistant part (14a, 14b, 14c), at least when the equidistant part (14a, 14b, 14c) is facing towards the second roller (2) and crosses the join plane (U), so that the central part (Sc) of a sheet article (S) in contact with the lateral surface (11 ) is not aspirated by the retaining means (15) and the respective retaining means (25) draw or receive the central part (Sc).

[0069] The respective retaining means (25) are arranged and / or configured in such a way as to avoid retaining in the respective equidistant part (24a, 24b, 24c), at least when the respective equidistant part (24a, 24b, 24c) is facing towards the first roller (1 ) and crosses the join plane (U), in such a way that the central part (Sc) of a sheet article (S) in contact with the respective lateral surface (21 ) is not aspirated by the respective retaining means (25) and the retaining means (15) draw or receive the central part (Sc).

[0070] The retaining means (15) are configured to retain at least when each of the two ends (12a, 13a, 12b, 13b, 12c, 13c) moves along a first portion (T1a) between the join plane (U) and the first folding area (P1 ) so as to retain ends (Se, Se’) of sheet articles (S) received by successive parts of the two or more parts (11a, 11 b, 11c, 11 d) and a central part (Sc) of a sheet article (S) received by a portion of the two or more portions (21a, 21 b, 21c, 21 d).

[0071] The respective retaining means (25) are configured to retain at least when each of the respective two ends (22a, 23a, 22b, 23b, 22c, 23c) moves along a respective first portion (T1b) between the join plane (U) and the second folding area (P2) so as to retain ends (Se, Se’) of sheet articles (S) received by successive portions of the two or more portions (21a, 21 b, 21c, 21 d) and a central part (Sc) of a sheet article (S) received by a part of the two or more parts (11a, 11b, 11c, 11 d).

[0072] The machine (1000) described above enables production of stacks (P) of napkins of differing types, as figures from 22 to 39 show by way of example.

[0073] The sheet articles (S) have precise cuts and the machine (1000) prevents imperfections due to dealignments and / or crushing of the sheet articles (S) which instead occur in the solutions of the prior art, such as for example those illustrated in DE2853741A1.

[0074] The productivity of the machines for making napkins suffers from the velocity of the V-folding of the sheet articles (S). Given a same technology, or speed of folding, the machine (1000) of the invention practically doubles the productivity with respect to the existing solutions, such as the ones already described.

[0075] The machine (1000) of the invention thus enables limiting the size given a same productivity.

[0076] The stack (P) obtained further has an advantageous arrangement of the sheet articles (S) as the central fold lines (Scentr) are arranged alternatively on a side and on the opposite side. A comparison between figures 1 and 2 enables appreciating the different arrangement of the sheet articles (S) which makes the stack (P) more homogeneous with advantages in the successive management thereof, from the packaging to the extraction from the packaging of the single sheet article (S).

[0077] As known to the technical expert in the field, retaining in the equidistant part (14a, 14b, 14c) can be avoided, as can retaining in the respective equidistant part (24a, 24b, 24c) thus avoiding arranging the retaining means (15) and the respective retaining means (25) in these areas and / or with an appropriate configuration thereof, i.e. with an appropriate activation; for example, by avoiding aspirating in those areas, at least during the course of the crossing of the join plane (U) as described above.

[0078] In the accompanying figures the cylindrical lateral surface (11 ) of the first roller (1 ) is subdivided into three parts as is the respective cylindrical lateral surface (21 ) of the second roller (2) with the exception that in figures 20 and 21 the parts are four in number. In the sections of the first roller (1 ) and the second roller (2) in the accompanying figures the first rotation axis (X1 ) and the second rotation axis (X2) are both in the sheet article and horizontal.

[0079] The same figures show how preferably the join plane (U) is a horizontal plane and how the sheet articles (S) cross it vertically, arranged on a first succession (T1 ) and a second succession (T2), as they can arrive in a vertical or circular trajectory. As can be observed in figure 14, the position of the first folding area (P1 ) is definable from the angle formed between the join plane (U) and a plane passing through the first rotation axis (X1 ) and the distancing area of the sheet articles (S) from the lateral surface (11 ) and the position of the second folding area (P2) is definable from the angle formed between the join plane (U) and a plane passing through the second rotation axis (X2) and the distancing area of the sheet articles (S) from the respective lateral surface (21 ).

[0080] Figure 14 also enables observing the orientation of the first roller (1 ) and the second roller (2) respectively with respect to the first rotation axis (X1 ) and the second rotation axis (X2) and therefore between one another. The angular position of the second roller (2) is such that the respective equidistant part (24a, 24b, 24c) is about to cross the join plane (U) together with two ends (12a, 13a, 12b, 13b, 12c, 13c) of successive parts of the two or more parts (11a, 11 b, 11c, 11d).

[0081] With the exclusion of figures 9, 20 and 21 , the embodiments of the machine (1000) shown in the other figures show aspiration blocks at the equidistant parts (14a, 14b, 14c) and at the respective equidistant parts (24a, 24b, 24c). Obviously, the aspiration blocks must not be active on the crossing of the join plane (U) when they are facing towards the other roller, between the first roller (1 ) and the second roller (2) In a use mode, the suction line connected to the aspiration blocks is kept switched off while in a different use mode the suction line connected to the aspiration blocks is kept switched on between the inlet area (11 ), or the respective inlet area (I2), and the join plane (U), then is switched off at the passage of the sheet article (S) from the first roller (1 ) to the second roller (2), or vice versa.

[0082] The aspiration blocks have been illustrated to show how the machine (1000) according to the invention can be made for a plurality of types of production: the machine (1000) is therefore more flexible than the prior art solutions.

[0083] The retaining means (15) are typically configured to retain at each of the two ends (12a, 13a, 12b, 13b, 12c, 13c) until the first folding elements (3) enter into contact with the sheet articles (S) and the respective retaining means (25) are configured to retain at each of the two respective ends (22a, 23a, 22b, 23b, 22c, 23c) until the second folding elements (4) enter into contact with the sheet articles (S). However the machine (1000) could exploit the inertias, for example by aspirating on a shorter portion, or it might exploit the superiority of the first folding elements (3) and the second folding elements (4) in displacing the sheet articles (S), for example by continuing to aspirate even after the contact with the sheet articles (S). The lateral surface (11 ) and the respective lateral surface (21 ) typically have the same diameter (11diam, 21diam).

[0084] Typically the first portion (T1a) extends between the first folding area (P1 ) and the respective first portion (T1 b) to the second folding area (P2).

[0085] The first portion (T1a) preferably extends from the join plane (U) and the respective first portion (T1 b) extends from the join plane (U).

[0086] The retaining means (15) preferably retain only at the two ends (12a, 13a, 12b, 13b, 12c, 13c) and the respective retaining means (25) retain only at the two respective ends (22a, 23a, 22b, 23b, 22c, 23c).

[0087] The functioning and, possibly, the structure of the machine (1000) is therefore simpler while guaranteeing the correct movement of the articles in sheet form (S) and there are fewer risks that the passage of the central parts (Sc) of the sheet articles (S) from the first roller (1 ) to the second roller (2’), and vice versa, will not occur.

[0088] The vertical arrangement of the machine (1000) illustrated in the figures 12, 14, 20 and 21 enables limiting the dimensions and realising a machine with less encumbrance on the ground surface.

[0089] The machine (1000) preferably comprises two supply lines (100, 200), so as to facilitate the transfer of the sheet articles (S) towards the first roller (1 ) and the second roller (2), with each of the two supply lines (100, 200) being able to cut the sheet articles (S) following the same time lapses required by the lateral surface (11 ) or the respective lateral surface (21 ) and being able to directly transfer the just-cut sheet articles (S) to one of the lateral surfaces.

[0090] In particular, it is preferable that

[0091] - the at least a supply line (100, 200) comprises a second strip supply line (210), second folding means (220), for longitudinally folding a strip (N1 , N2), and second cutting means (230), for cutting sheet articles (S) from a longitudinally folded strip (N1 p, N2p);

[0092] - the cutting means (130) comprise at least a blade or counter-blade (131 ) and a first cutting roller (132) comprising first retaining means (133) of sheet articles (S) and are downstream of the folding means (120) and of the strip supply line (110) so that the first cutting roller (132) cuts with the at least a blade or counter-blade (131 ) sheet articles (S) from a first longitudinally folded strip (N1 p); - the second cutting means (230) comprise at least a respective blade or counterblade (231 ) and a second cutting roller (232) comprising second retaining means (233) for retaining sheet articles (S) and are downstream of the second folding means (220) and of the second strip supply line (210) so that the second cutting roller (232) cuts, with the at least a respective blade or counter-blade (231 ), sheet articles (S) from a second longitudinally folded strip (N2p);

[0093] - the first roller (1 ) is downstream of the first cutting roller (132) and receives the sheet articles (S) cut from the first cutting roller (132);

[0094] - the second roller (2) is downstream of the second cutting roller (232) and receives the sheet articles (S) cut from the second cutting roller (232)

[0095] - the first cutting roller (132), the second cutting roller (232), the first roller (1 ) and the second roller (2) rotate at a same tangential velocity (w1 , w2), i.e. they have the same modulus.

[0096] With the aim of clarifying the illustration of figure 12, the two supply lines (100, 200) are represented on opposite sides, but they are typically on the same side.

[0097] Typically the first roller (1 ) receives the sheet articles (S) from an inlet area (11 ) and the second roller (2) receives the sheet articles (S) from a respective inlet area (I2).

[0098] In the embodiments of the appended figures the inlet area (11 ) is located above the join plane (U), i.e. on the side opposite the support means (5), and the respective inlet area (I2) is located above the join plane (U), i.e. on the side opposite the support means (5), but the inlet area (11 ) and the respective inlet area (I2) might also be positioned by the side, although the upper position allows, in general, best exploiting the extension of the machine (1000) in the vertical direction.

[0099] The retaining means (15) and the respective retaining means (25) shown by way of example in the embodiment of figure 12 respectively comprise suction holes (16, 17) and respective suction holes (26, 27) which operate in the first portion (T1a) and in the respective first portion (T1b). The retaining means (15) and the respective retaining means (25) shown by way of example in the embodiments of figures 20 and 21 comprise pliers (19) and respective pliers (29) which in the first portion (T1a) and in the respective first portion (T1b) operate in a similar way to the suction holes (16, 17) and respective suction holes (26, 27) of the embodiment of figure 12. The retaining means (15) and the respective retaining means (25) can therefore comprise pliers (19) and respective pliers (29). As known to the technical expert in the field, the pliers (19) and respective pliers (29) in general cooperate with suction systems, such as those exemplified in figures 20 and 21.

[0100] In a preferred embodiment the retaining means (15) comprise suction holes (16, 17) arranged at the two ends (12a, 13a, 12b, 13b, 12c, 13c) and respective retaining means (25) comprise respective suction holes (26, 27) arranged at the two respective ends (22a, 23a, 22b, 23b, 22c, 23c).

[0101] The suction holes (16, 17) aspirate in the at least a first portion (T1a) as described above in general terms, typically as far as the first folding area (P1 ), and the respective suction holes (26, 27) aspirate in the at least a respective first portion (T1 b) as described above in general terms, typically as far as the second folding area (P2).

[0102] The suction holes (16, 17) preferably aspirate from the inlet area (11 ) to the end of the first portion (T1a) and the respective suction holes (26, 27) aspirate from the respective inlet area (I2) to the end of the respective first portion (T1 b).

[0103] In a further embodiment, the retaining means (15) comprise openings (18) and pliers (19) for retaining the sheet articles (S). Each plier (19) is movable in the opening (18) between a gripping position (pre) and a release position (nil) and each opening (18) is between two parts of the two or more parts (11a, 11 b, 11c, 11 d). The respective retaining means (25) comprise respective openings (28) and respective pliers (29) for retaining sheet articles (S). Each respective plier (29) is movable in the respective opening (28) between an engaged position and a disengaged position (dis) and each respective opening (28) is between two portions of the two or more portions (21 a, 21 b, 21 c, 21 d).

[0104] Further, each respective equidistant part (24a, 24b, 24c) has a respective protuberance (24p) to push a sheet article (S) into an opening (18) and each equidistant part (14a, 14b, 14c) has a protuberance (14p) for pushing a sheet article (S) into a respective opening (28).

[0105] The pliers (19) are again in a gripping position (pre) at least in the first portion (T1a) as described above in general terms, typically as far as the first folding area (P1 ), and the respective pliers (29) are in an engaged position at least in the respective first portion (T1 b) as described above in general terms, typically up to the second folding area (P2).

[0106] Typically, in the above-described case, in which the first roller (1 ) and the second roller (2) receives the sheet articles (S) from a respective inlet area (11 ) and a respective inlet area (I2), the retaining means (15) comprise suction holes (16, 17) arranged at the two ends (12a, 13a, 12b, 13b, 12c, 13c) and respective retaining means (25) comprise respective suction holes (26, 27) arranged at the two respective ends (22a, 23a, 22b, 23b, 22c, 23c). The suction holes (16, 17) and respective suction holes (26, 27) retain, over an initial portion, indicatively up to the join plane (U). As shown by way of example in figures 20 and 21 , typically at least a part of the suction holes (16, 17) and at least a part of the respective suction holes (26, 27) retain until the pliers (19) in transit from the join plane (U) pass into the gripping position (pre) or the respective pliers (29) in transit from the join plane (U) pass into the engaged position, after a respective protuberance (24p) has disengaged an opening (18) or after a protuberance (14p) has disengaged a respective opening (28).

[0107] As illustrated in figure 12, in the case of use of suction holes (16, 17) and respective suction holes (26, 27) to retain the central part (Sc) received by the second roller (2) or by the first roller (1 ), the retaining means (15) and the respective retaining means (25) retain the central part (Sc) from the join plane (U) or substantially thereat, i.e. the tangential point.

[0108] As illustrated in figures 20 and 21 , in the case of use of the pliers (19) and respective pliers (29) to retain the central part (Sc) received by the second roller (2) or by the first roller (1 ), the retaining means (15) and the respective retaining means (25) retain the central part (Sc) after the respective protuberance (24p) or the protuberance (14p) have freed the opening (18) or the respective opening (28), or from an area or a point below the join plane (U).

[0109] Figure 9 demonstrates how the at least a supply line (100, 200) can be made in many ways.

[0110] The first folding means (120) and the second folding means (220) generally comprise respective fold line triangles which the belt (N1 , N2) tends to follow, thus folding longitudinally as illustrated by way of example in figures 12 and 13. As also described in EP0402324B1 , arrangements of fold line triangles are known in the sector that enable obtaining the variants of the at least a fold line (Sp, Sp’, Sp”) illustrated by way of example in figures from 22 to 39.

[0111] There are numerous possible embodiments of the cutting means (130) and the second cutting means (230) known to the technical expert in the sector. For example the appended figures illustrate a blade or counter-blade (131 ) and a respective blade or counter-blade (231 ), both fixed, which cooperate respectively with the first cutting roller (132) and the second cutting roller (232) but these might cooperate with further cutting rollers, each having one or more blades.

[0112] The embodiment of figure 9 shows a plate conveyor (140) and a respective plate conveyor (240) which convey sheet articles (S), but other devices might be used, such as, for example, a vacuum belt conveyor. The expert in the field is aware of various ways of arriving at the first succession (T1) and the second succession (T2) of the sheet articles (S) of figure 9 starting from one or more reels, generally made of paper. For example, a single cutting roller might supply two roller units which, by means of different velocities, realise the first succession (T1 ) and the second succession (T2) or the first cutting roller (132) and the second cutting roller (232) might supply the plate conveyor (140) and the respective plate conveyor (240), possibly with the interposing of intermediate rollers. The presence of two supply lines (100, 200) reduces the number of transfers of the sheet articles (S) and / or avoids the use of velocity variations, particularly critical as they occur on a longitudinally folded strip (N1 p, N2p).

[0113] The direct passage of the sheet articles (S) between the first cutting roller (130) and the first roller (1 ) and the direct passage of the sheet articles (S) between the second cutting roller (230) and the second roller (2) facilitates the correct positioning of the sheet articles (S) on the lateral surface (11 ) of the first roller (1 ) and on the respective lateral surface (21 ) of the second roller (2).

[0114] Figures 6 and 7 show a further embodiment of the stack (P) of the invention which differs from the one of figures 2 and 8 as it has at least the at least a more external fold line (Sp, Sp’, Sp”) facing alternatively on one side and on the opposite side, thus obtaining the advantages of uniformity and compactness of the stack (P) already described also in the other horizontal direction.

[0115] The stack of figures 6 and 7 can easily be obtained with the machine (1000) of the invention simply by supplying the sheet articles (S) of the first succession (T1 ) and of the second succession (T2) so that they have the corresponding fold lines of the at least a fold line (Sp, Sp’, Sp”) opposite one another according to a vertical plane orthogonal with respect to the first rotation axis (X1 ) and the second rotation axis (X2).

[0116] In the machine (1000) of figure 12 this is easily obtainable by orientating the fold line triangles to the left of the forming means (10) in the opposite direction to the triangles to the right of the forming means (10), for example in such a way that the single fold line represented by one or more longitudinal folds (Np) faces the observer on the left and spaced away from the observer on the right.

[0117] The at least a supply line (100, 200) is preferably configured so that the sheet articles (S) on the lateral surface (11 ) and on the respective lateral surface (21 ) have the folds of the at least a fold line (Sp, Sp’, Sp”) corresponding to one another facing in opposite directions with respect to a direction parallel to the first rotation axis (X1 ) and to the second rotation axis (X2).

[0118] The embodiment of figure 12 also schematically illustrates two reel unwinders (111 , 211 ) of known type as well as reel cutters (112) and second reel cutters (212) for cutting strips from a reel, both of known type.

[0119] Methods are known for realising retaining means (15), the respective retaining means (25), the first retaining means (133) or the second retaining means (233), as for example discussed in EP3724112B1 , in EP3067303B1 or in EP1457444B2. The holes shown by way of example in the first retaining means (133) and in the second retaining means (233) of figures 20 and 21 are also examples of those present in the embodiment of figure 12.

[0120] In figures 9 and 14 the retaining means (15) comprise rows of suction holes (16, 17) arranged in the direction of the first rotation axis (X1 ) and connected to a cylindrical opening which extends for a portion of circumference and is connected to an aspirating conduit, i.e. to means for distributing the depression. In other words, the suction holes (16, 17) aspirate exclusively when they flank the cylindrical opening during the rotation. By way of example, the cylindrical opening of figure 9 extends by a portion, i.e. by an angle of circumference that is smaller with respect to the cylindrical opening of figure 14. Likewise, in figures 9 and 14, the respective retaining means (25) comprise respective rows of suction holes (26, 27) arranged in the direction of the second rotation axis (X2) and connected to a respective cylindrical opening which extends by a portion of circumference and is connected to a respective aspirating conduit, i.e. to respective means for distributing the depression. In other words, the respective suction holes (16, 17) aspirate exclusively when they flank the respective cylindrical opening during the rotation. In this case too the respective cylindrical opening of figure 9 extends by a portion that is smaller that the respective cylindrical opening of figure 14.

[0121] The aspiration close to the pliers (19) and the respective pliers (29) facilitates the transfer of the sheet articles (S) towards the first roller (1 ) and the second roller (2) and is of known type.

[0122] The support means (5) are schematically represented in figures 9, 11 , 14, 15, 16, 17, 18 and 19. The example diagram comprises vertically-mobile forming tables (51 ) and separating tables (52) which are mobile at least horizontally in order to be placed between a formed stack (P) on the forming tables (51 ) and the sheet articles (S) in arrival.

[0123] The first folding elements (3) and second folding elements (4) are known in the sector and described, for example, in EP2437994B1. As illustrated by way of example in figure 15, the movement thereof is coordinated with that of the first roller (1 ) and the second roller (2) between an upper position internally of a recess and a lower position between the first roller (1 ) or the second roller (2) and the support means (5).

[0124] The invention also relates to a method for producing, from strips (N1 , N2), stacks (P) of sheet articles (S) folded in a V shape, on a central fold line (Scentr) between the two ends (Se, Se’) of the V, as well as folded on at least a fold line (Sp, Sp’, Sp”), orthogonal to the central fold line, which extends between the two ends (Se, Se’) of the V.

[0125] An embodiment of the method comprises steps of:

[0126] - - providing at least a strip (N1 , N2), preferably made of paper;

[0127] - - longitudinally folding the at least a strip (N1 , N2) so as to form one or more longitudinal folds (Np);

[0128] - transversally cutting the at least a longitudinally folded strip (N1 p, N2p) so as to obtain sheet articles (S) that are identical to one another having a length (SI) between two ends (Se, Se’) and at least a fold line (Sp, Sp’, Sp”) between the two ends (Se, Se’);

[0129] - flanking sheet articles (S) between them so as to create a first succession (T1 ) of sheet articles (S) and a second succession (T2) of sheet articles (S) flanked and staggered by half a length (SI);

[0130] - folding the flanked sheet articles (S) in a V shape, by pulling the proximal ends (Se, Se’) of two successive sheet articles (S) of the first succession (T1 ) together with the part, of the sheet article (S) of the second succession (T2), flanked to the same ends (Se, Se’) on the side of the first succession (T1 ) until forming a central fold line (Scentr) and by pulling the proximal ends (Se, Se’) of two successive sheet articles (S) of the second succession (T2) together with the part, of the sheet article (S) of the first succession (T1 ), flanked to the same ends (Se, Se’) on the side of the second succession (T2) until forming a central fold line (Scentr);

[0131] - forming a stack (P) of sheet articles (S) folded in a V shape one above the other.

[0132] The above-discussed advantages are obtained in this way in terms of uniformity and compactness of the stack (P).

[0133] Similarly to what is illustrated for the machine, the method preferably enables obtaining a stack (P) alike to those of figures 6 and 7.

[0134] In the step of flanking the sheet articles (S), the folds of the at least a fold line (Sp, Sp’, Sp”) of the first succession (T1 ) and the corresponding folds of the at least a fold line (Sp, Sp’, Sp”) of the second succession (T2) preferably face in opposite directions, i.e. they face in horizontal directions that are identical to one another but in opposite senses.

[0135] As is evident from the above description, the invention enables obtaining a stack (P).

[0136] An embodiment of the stack (P) comprises sheet articles (S), identical to one another and superposed. Each sheet article (S) is folded in a V shape, on a central fold line (Scentr) between the two ends (Se, Se’) of the V, as well as folded on at least a fold line (Sp, Sp’, Sp”), orthogonal to the central fold line, which extends between the two ends (Se, Se’) of the V.

[0137] Figures from 22 to 39 show examples of like sheet articles (S).

[0138] The central fold line (Scentr) of a sheet article (S) faces in an opposite direction to the central fold line (Scentr) of the sheet article (S) or of the sheet articles (S) positioned above and / or beneath, as shown by way of example in figures 2, 6, 7 and 8.

[0139] The folds of the at least a fold line of a sheet article (Sp, Sp’, Sp”) preferably face in an opposite direction to the corresponding folds of the at least a fold line (Sp, Sp’, Sp”) of a sheet article (S) or of the sheet articles (S) positioned above and / or beneath, as shown by way of example in figures 6 and 7. For example, figure 6 illustrates the fold of the at least a fold line (Sp, Sp’, Sp”) of the upper sheet article (S) on the opposite side, not in view, of the corresponding fold line of the at least a fold line (Sp, Sp’, Sp”) of the successive sheet article (S); likewise the fold line of the at least a fold line (Sp, Sp’, Sp”) of the sheet article still further below is newly on the in-view side of the stack (P).

[0140] The stacks (P) obtained with the machine or the method according to the invention have more uniform sizes with respect to those of the prior art, as they prevent the fold lines from overlapping on one side as instead happens in figures 1 , 3 and 5.

[0141] It is understood that the above has been described by way of non-limiting example and that any constructional variants are considered to fall within the protective scope of the present technical solution, as claimed in the following.

Claims

CLAIMS1 ) A machine (1000) for producing, from strips, (N1 , N2) stacks (P) of sheet articles (S) folded in a V shape, on a central fold line (Scentr) between the two ends (Se, Se’) of the V, as well as folded on at least a fold line (Sp, Sp’, Sp”), orthogonal to the central fold line (Scentr), which extends between the two ends (Se, Se’) of the V, comprising:- at least a supply line (100, 200) of sheet articles (S) identical to one another and folded on at least a fold line (Sp, Sp’, Sp”) comprising a strip supply line (110), folding means (120), for longitudinally folding a strip (N1 , N2), and cutting means (130), for cutting sheet articles (S) from a longitudinally folded strip (N1 p, N2p);- forming means (10), for forming stacks (P) of sheet articles (S) folded in a V shape, which comprise a first roller (1 ) which has a lateral surface (11 ) for receiving sheet articles (S) and which rotates with respect to a first rotation axis (X1 ), a second roller (2) which has a respective lateral surface (21 ) for receiving sheet articles (S) and which rotates with respect to a second rotation axis (X2) which is parallel to the first rotation axis (X1 ) and which insists together with the first rotation axis (X1 ) on a join plane (U), support means (5), for supporting a stack (P) of sheet articles (S) folded in a V shape beneath the first roller (1 ) and the second roller (2), first folding elements (3) which, at a first folding area (P1 ), move the sheet articles (S) from the lateral surface (11 ) towards the support means (5) so as to form a central fold line (Scentr) and second folding elements (4) which, at a relative second folding area (P2), move the sheet articles (S) from the respective lateral surface (21 ) towards the support means (5) so as to forma central fold line (Scentr), wherein:- the first roller (1 ) comprises retaining means (15) of the sheet articles (S) which are arranged in such a way as to divide the lateral surface (11 ) into two or more parts (11a, 11 b, 11c, 11d) which define angles of circumference (alfa) that are identical to one another, each for retaining a sheet article (S) and each having two ends (12a, 13a, 12b, 13b, 12c, 13c) and an equidistant part (14a, 14b, 14c) which is equidistant from the two ends (12a, 13a, 12b, 13b, 12c, 13c);- the retaining means (15) are arranged so as to retain a sheet article (S) at least at each of the two ends (12a, 13a, 12b, 13b, 12c, 13c) of each of the two or more parts (11a, 11 b, 11c, 11d);- the second roller (2) comprises respective retaining means (25) of sheet articles (S) which are arranged in such a way as to divide the respective lateral surface (21 ) into two or more portions (21a, 21 b, 21c, 21 d) which define angles of circumference (alfa) that are identical to one another, each for retaining a sheet article (S) and each having two respective ends (22a, 23a, 22b, 23b, 22c, 23c) and a respective equidistant part (24a, 24b, 24c) which is equidistant from the two respective ends (22a, 23a, 22b, 23b, 22c, 23c);- the respective retaining means (25) are arranged so as to retain a sheet article (S) at least at each of the two respective ends (22a, 23a, 22b, 23b, 22c, 23c) of each of the two or more portions (21a, 21 b, 21 c, 21 d);- the at least a supply line (100, 200) of sheet articles (S) feeds, with a sheet article (S), each of the two or more parts (11a, 11 b, 11c, 11 d) and each of the two or more portions (21a, 21 b, 21c, 21 d);- the first rotation axis (X1 ) and the second rotation axis (X2) are spaced from oneanother in such a way that, at the join plane (U), two flanked sheet articles (S) can be interposed between the lateral surface (11 ) and the respective lateral surface (21 ), the retaining means (15) can act on the sheet article (S) interposed more closely to the respective lateral surface (21 ) and the respective retaining means (25) can act on the sheet article (S) interposed more closely to the lateral surface (11 );- the first roller (1 ) and the second roller (2) rotate at a same tangential velocity (w1 , w2), with opposite rotation directions to one another;- the first roller (1 ) is orientated with respect to the first rotation axis (X1 ) and the second roller (2) is orientated with respect to the second rotation axis (X2) so that during the rotation thereof an end (12a, 13a, 12b, 13b, 12c, 13c) crosses the join plane (U) together with a respective equidistant part (24a, 24b, 24c) facing towards the first roller (1 ) and, vice versa, a respective end (22a, 23a, 22b, 23b, 22c, 23c) crosses the join plane (U) together with a respective equidistant part (14a, 14b, 14c) facing towards the second roller (2);- the retaining means (15) are arranged and / or configured in such a way as to avoid retaining in the equidistant part (14a, 14b, 14c), at least when the equidistant part (14a, 14b, 14c) is facing towards the second roller (2) and crosses the join plane (U), so that the central part (Sc) of a sheet article (S) in contact with the lateral surface (11 ) is not aspirated by the retaining means (15) and the respective retaining means (25) draw or receive the central part (Sc);- the respective retaining means (25) are arranged and / or configured in such a way as to avoid retaining in the respective equidistant part (24a, 24b, 24c), at least when the respective equidistant part (24a, 24b, 24c) is facing towards the first roller (1 ) and crosses the join plane (U), in such a way that the central part (Sc) ofa sheet article (S) in contact with the respective lateral surface (21 ) is not aspirated by the respective retaining means (25) and the retaining means (15) draw or receive the central part (Sc);- the retaining means (15) are configured to retain at least when each of the two ends (12a, 13a, 12b, 13b, 12c, 13c) moves along a first portion (T1a) between the join plane (U) and the first folding area (P1 ) so as to retain ends (Se, Se’) of sheet articles (S) received by successive parts of the two or more parts (11a, 11 b, 11c, 11d) and a central part (Sc) of a sheet article (S) received by a portion of the two or more portions (21a, 21 b, 21c, 21 d) and the respective retaining means (25) are configured to retain at least when each of the respective two ends (22a, 23a, 22b, 23b, 22c, 23c) moves along a respective first portion (T1b) between the join plane (U) and the second folding area (P2) so as to retain ends (Se, Se’) of sheet articles (S) received by successive portions of the two or more portions (21a, 21 b, 21c, 21 d) and a central part (Sc) of a sheet article (S) received by a part of the two or more parts (11a, 11b, 11c, 11 d).2) The machine (1000) of claim 1 , wherein the first portion (T1a) extends between the join plane (U) and the first folding area (P1 ) and wherein the respective first portion (T1 b) extends from the join plane (U) to the second folding area (P2).3) The machine (1000) of claim 1 or 2, wherein the retaining means (15) retain only at the two ends (12a, 13a, 12b, 13b, 12c, 13c) and wherein the respective retaining means (25) retain only at the two respective ends (22a, 23a, 22b, 23b, 22c, 23c).4) The machine (1000) of any one of the preceding claims, wherein:- the at least a supply line (100, 200) comprises a second strip supply line (210),second folding means (220), for longitudinally folding a strip (N1 , N2), and second cutting means (230), for cutting sheet articles (S) from a longitudinally folded strip (N1 p, N2p);- the cutting means (130) comprise at least a blade or counter-blade (131 ) and a first cutting roller (132) comprising first retaining means (133) of sheet articles (S) and are downstream of the folding means (120) and of the strip supply line (110) so that the first cutting roller (132) cuts with the at least a blade or counter-blade (131 ) sheet articles (S) from a first longitudinally folded strip (N1 p);- the second cutting means (230) comprise at least a respective blade or counterblade (231 ) and a second cutting roller (232) comprising second retaining means (233) for retaining sheet articles (S) and are downstream of the second folding means (220) and of the second strip supply line (210) so that the second cutting roller (232) cuts, with the at least a respective blade or counter-blade (231 ), sheet articles (S) from a second longitudinally folded strip (N2p);- the first roller (1 ) is downstream of the first cutting roller (132) and receives the sheet articles (S) cut from the first cutting roller (132);- the second roller (2) is downstream of the second cutting roller (232) and receives the sheet articles (S) cut from the second cutting roller (232)- the first cutting roller (132), the second cutting roller (232), the first roller (1 ) and the second roller (2) rotate at a same tangential velocity (w1 , w2).5) The machine (1000) of the preceding claim, wherein the first roller (1 ) receives the sheet articles (S) from an inlet area (11 ), the retaining means (15) comprise suction holes (16, 17) arranged at the two ends (12a, 13a, 12b, 13b, 12c, 13c) which aspirate from the inlet area (11 ) to the end of the first portion (T1 a), the second roller (2) receives the sheet articles (S) from a respective inlet area (I2)and the respective retaining means (25) comprise respective suction holes (26, 27) arranged at the two respective ends (22a, 23a, 22b, 23b, 22c, 23c) which aspirate from the respective inlet area (12) to the end of the respective first portion (T1 b).6) The machine (1000) of any one of claims from 1 to 4, wherein:- the retaining means (15) comprise openings (18) and pliers (19), each plier (19) being movable in the opening (18) between a gripping position (pre) and a release position (hl) and each opening (18) being between two parts of the two or more parts (11a, 11 b, 11c, 11d);- the respective retaining means (25) comprise respective openings (28) and respective pliers (29), each respective plier (29) being movable in the respective opening (28) between an engaged position and a disengaged position (dis) and each respective opening (28) being between two portions of the two or more portions (21a, 21 b, 21c, 21 d);- each respective equidistant part (24a, 24b, 24c) has a respective protuberance (24p) to push a sheet article (S) into an opening (18);- each equidistant part (14a, 14b, 14c) has a protuberance (14p) for pushing a sheet article (S) into a respective opening (28);- at least in the first portion (T 1 a) the pliers (19) are in gripping position (pre);- at least in the respective first portion (T1 b) the respective pliers (29) are in engaged position.7) The machine (1000) of any one of the preceding claims, wherein the at least a supply line (100, 200) is configured so that the sheet articles (S) on the lateral surface (11 ) and on the respective lateral surface (21 ) have the folds of the at least a fold line (Sp, Sp’, Sp”) corresponding to one another facing in oppositedirections with respect to a direction parallel to the first rotation axis (X1 ) and to the second rotation axis (X2).8) A method for producing, from strips (N1 , N2), stacks (P) of sheet articles (S) folded in a V shape, on a central fold line (Scentr) between the two ends (Se, Se’) of the V, as well as folded on at least a fold line (Sp, Sp’, Sp”), orthogonal to the central fold line (Scentr), which extends between the two ends (Se, Se’) of the V, comprising steps of:- - providing at least a strip (N1 , N2);- - longitudinally folding the at least a strip (N1 , N2) so as to form one or more longitudinal folds (Np);- transversally cutting the at least a longitudinally folded strip (N1 p, N2p) so as to obtain sheet articles (S) that are identical to one another having a length (SI) between two ends (Se, Se’) and at least a fold line (Sp, Sp’, Sp”) between the two ends (Se, Se’);- flanking sheet articles (S) between them so as to create a first succession (T1 ) of sheet articles (S) and a second succession (T2) of sheet articles (S) flanked and staggered by half a length (SI);- folding the flanked sheet articles (S) in a V shape, by pulling the proximal ends (Se, Se’) of two successive sheet articles (S) of the first succession (T1 ) together with the part, of the sheet article (S) of the second succession (T2), flanked to the same ends (Se, Se’) on the side of the first succession (T1 ) until forming a central fold line (Scentr) and by pulling the proximal ends (Se, Se’) of two successive sheet articles (S) of the second succession (T2) together with the part, of the sheet article (S) of the first succession (T1 ), flanked to the same ends (Se, Se’) on the side of thesecond succession (T2) until forming a central fold line (Scentr);- forming a stack (P) of sheet articles (S) folded in a V shape one above the other.9) The method of the preceding claim wherein in the step of flanking the sheet articles (S), the folds of the at least a fold line (Sp, Sp’, Sp”) of the first succession (T1 ) and the corresponding folds of the at least a fold line (Sp, Sp’, Sp”) of the second succession (T2) face in opposite directions.

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