Patent Description:
As it is known, in the paper industry many types of machines and processes are used for producing paper tissues, towels, and similar products in packages of interfolded sheets of a determined height. These are obtained by folding the sheets in an "interfolded" way that means closing at each fold a final edge of the previous sheet and a starting edge of the following sheet.

In this way, at the moment of its use, when a sheet is extracted from the package, also an initial edge of the following sheet is extracted, thus simplifying its use for some kinds of uses.

The interfolding machines of known type work one or more webs of paper coming from one or more reels and that are cut at a cutting unit into sheets of predetermined length, and staggered fed to a folding unit at which <NUM> counter-rotating folding rolls work. More precisely, the cut into sheets of the webs is carried out on cutting rolls which alternately cooperate with related counter-blades.

Among the possible ways to fold the sheets, are known, in particular, the "L" and "V" interfolded, with <NUM> panels, the "Z" interfolded, with <NUM> panels, and the "W" interfolded, with <NUM> panels.

In the case of "L" and "V" interfolded, obtained by "single-fold" machines, of the type that is for example described in <CIT>, the webs of paper are cut in such a way to form two staggered sequences of sheets which are alternately fed to the folding rolls. In this way, each sheet coming from a first direction is superimposed, for about half sheet, to a portion of the sheet coming from a second direction, and vice versa, at the moment in which the fold is carried out.

In the case of "Z", "W", or even more interfolded panels, obtained by the so called "multi-fold" machines of the type for example described in <CIT>, only one web of paper is worked and, a sequence of sheets, which are already partially superimposed to each other, reaches the folding rolls from a single direction. As described in <CIT>, the superimposition between two following sheets is carried out immediately after the cut by a transfer roll and a delay roll, which together carry out a small fold at a previous sheet under which the following sheet is in part positioned.

Both in the single-fold and in the multi-fold machines, the folding rolls have a circumference whose length is a multiple of the panel length. In particular, in order to fold or interfold the sheets, the folding rolls are provided with retaining devices, such as suction holes, or mechanical pliers, which are synchronously operated for alternately starting and finishing each fold between two following panels.

For example, as described in <CIT> which provides advancing rolls and folding rolls having suction holes, a first series of holes holds the sheets on a folding roll for a determined angular distance, and then "passes" them to the other folding roll also this provided with a parallel retaining device with suction holes, which works for another predetermined angular distance. Through this controlled "passage" of the sheet or web of paper from a folding roll to another one, the desired folding or interfolding configuration is carried out obtaining a stack of folded or interfolded sheets. Since the "panel length", which determines the width of the package of folded sheets exiting the machine, is a submultiple of the circumferential development of the folding rolls, is, therefore, one of the main structural constraints of the folding machines, which impede to change the length of the panels without completely replacing the folding rolls.

Therefore, both in the case of multi-fold machines and in the case of single-fold machines of prior art, it is necessary to provide both the folding or interfolding rolls, and at least one cutting roll, in addition to the rolls which transfer the sheets cut by the cutting roll to the folding or interfolding rolls. Therefore, in addition to be complex from a structural point of view, the prior art machines have a great size. Furthermore, in the known machines, it is necessary to have suction rolls both for the cutting rolls and for the folding or interfolding rolls, resulting in high energy consumption for generating the vacuum necessary for aspiration.

Furthermore, both the multi-fold machines, and the single-fold machine of known type, have a high production rigidity, because, as anticipate above, both the folding or interfolding rolls, and the cutting rolls have a predetermined circumference whose length is a multiple of the panel length, whereby they are able to produce only a particular type of product.

In <CIT>, which discloses the preamble of claims <NUM> and <NUM>, an interfolding machine is described having a support structure comprising a folding section at which the sheets are fed to the folding rolls staggered to each other, and, then, folded in such a way to obtain a determined interfolding configuration. The folding section provides a modular structure comprising a portion that can be removed and replaced with an equivalent portion, but adapted to work with a different length of the panels.

Even though the solution described in <CIT> allows to make the machine a bit versatile because it allows to diversify the production of the machine, however, it requires long times to carry out the replacement of a module with another one having different characteristics with a not negligible loss of productivity. In particular, both the removal of the module from the machine and the installation of a new module are carried out by sliding the module along tracks parallel to the rolls of the machine. Therefore, the machine described in <CIT> has a big size in the direction longitudinal to the rolls, because it requires to have an available manoeuvring area having a length which is, at least, comparable to the length of the removed rolls. It is, furthermore, suitable to note that <CIT> does not describe in detail the devices that are able to cause the aforementioned sliding of the modules.

A drawback of the solution described in <CIT> relates, in particular, the replacement of the folding section. This, in fact, comprises both the cutting rolls and the folding rolls and the separation groups, in particular the detaching fingers which operate the detachment of the sheets from the surface of the folding rolls once that the replacement of the module has been made, have to be necessarily repositioned in phase with the new folding rolls, operation which is very complex.

It is, therefore, an object of the present invention to provide a machine for producing packages of laminar products, such as packages of napkins, tissues and similar products, able to overcome the aforementioned drawbacks of the prior art solutions.

It is, in particular, an object of the present invention to provide a machine for producing packages of laminar products, such as packages of napkins, tissues and similar products which allows to easily and quickly replace a portion of the machine with another one having the same functions.

It is, in particular, an object of the present invention to provide a machine for producing packages of laminar products, such as packages of napkins, tissues and similar products which allows to reduce the overall longitudinal dimension of the machine with respect to analogous solutions of prior art.

It is also an object of the present invention to provide a method for producing packages of laminar products having analogous advantages.

These and other objects are achieved by a machine for producing packages of laminar products made of paper material folded or interfolded, in particular packages of napkins, tissues, towels, or similar products, said machine comprising the features of claim <NUM>.

Other features of the invention are and related embodiments are set out in the dependent claims.

The displacement group is configured to move the support body from the assembled position to the disassembled position by lifting the support body from the support frame, in particular up to a predetermined height q1. The displacement group is, furthermore, configured to displace the support body from the disassembled position to the assembled position by lowering the support body on the support frame, in particular starting from the aforementioned predetermined height q1.

Advantageously, the displacement group can be configured to move the support body along a first displacement direction and at least a second displacement direction.

In particular, the first and second displacement directions can be orthogonal to each other.

In particular, the displacement group can be configured to lift, or lower, the support body causing the displacement of the same along the aforementioned first displacement direction. More in particular, the displacement group can be configured, furthermore, to displace the support body in the raised position from or towards the support frame causing the same to slide along the aforementioned second displacement direction.

In an embodiment foresee by the invention, the aforementioned displacement group can be configured to displace the support body between the assembled position and the disassembled position by a rotation about at least a rotation axis, preferably parallel to the longitudinal rotation axes of the first and second rolls. In a further alternative embodiment provided by the invention, the displacement group can be adapted to displace the support body between the assembled position and the disassembled position by at least a translation and at least a rotation.

In particular, a motor group can be, furthermore, configured to cause at least one between the first and second folding or interfolding rolls to rotate about the respective rotation axis. More in particular, the motor group can comprise a motor and a motion transmission device adapted to transmit the rotational motion of the motor shaft of the aforementioned motor to at least one between the first and second folding or interfolding roll.

Advantageously, the transmission group of the motion can comprise at least one motion transmission member, for example a transmission belt, adapted to cause the aforementioned rotation of at least one folding or interfolding roll, about the respective longitudinal axis.

Preferably, a group for adjusting the tension can be, furthermore, provided configured to adjust the tension of the or each motion transmission member, in particular of the aforementioned transmission belt.

In particular, the aforementioned group for adjusting the tension can be configured to keep the tension of the motion transmission member, substantially constant, or constant. More in particular, the group for adjusting the tension can be configured to keep constant or substantially constant, the tension of the motion transmission member during the movement of the support body from the assembled position to the disassembled position that is carried out by said displacement group.

In a possible embodiment, the group for adjusting the tension can comprise a measurement device configured to directly or indirectly measure the tension on the transmission belt, for example a force sensor, in particular a load cell.

Preferably, the aforementioned measurement device is operatively connected to a processing device configured to operate an actuation device adapted to cause a lengthening or a shortening of the path of the or each motion transmission member depending on a tension signal measured by the aforementioned measurement device.

Advantageously, each said first and second folding or interfolding roll comprises:.

Preferably, only one vacuum generation device is provided that is operatively connected to the vacuum distribution device of the first and of the second folding or interfolding roll.

In particular, the vacuum distribution device of the first and of the second folding or interfolding roll, and the or each vacuum generation device are pneumatically connected to each other by a connection duct.

More in particular, the aforementioned connection duct comprises:.

In a possible embodiment, the connection duct comprises, furthermore, a third portion configured to move from a connection position for connecting the first and second portions of the connection duct, and a disconnection position for disconnecting the first and the second portion of the connection duct.

In particular, the third portion can be slidingly mounted with respect to the first and second portions of the connection duct. More in particular, the third portion can be configured to move between a retracted position corresponding to the disconnection position, and an advanced position corresponding to the connection position. Advantageously, at least one sealing element is, furthermore, provided positioned between the third portion, in particular between internal surface of the third portion, and the first and/or the second portion, in particular the external surface of the first and/or of the second portion.

Advantageously, a first and a second sealing element can be provided adapted to be positioned between the first and the third portion and between the second and the third portion, respectively, at the aforementioned advanced position.

In particular, the or each sealing element can be configured to move from a working configuration, where is adapted to exert a sealing action to pneumatically isolate the first and second portions of the connection duct from the external environment, and a rest configuration, where is not adapted to exert a sealing action. For example, the or each sealing element can be pneumatically connected to an inflating device adapted to cause it to move from the rest configuration to the working configuration, in particular by introducing air or another gas, into each sealing element.

Preferably, can be, furthermore, provided:.

In particular, the first and second driving groups can be, furthermore, associated to a first and a second phase adjustment group configured to delay or anticipate the oscillatory motion of the first and second pluralities of detaching fingers with respect to a predetermined reference oscillatory motion, in such a way to delay or anticipate the instant (tr) at which the first and second pluralities of detaching fingers are adapted to alternately respectively cause the detachment of the folded or interfolded sheets of paper, from the first and second folding or interfolding roll.

More in particular, the first and second driving groups can be adapted to bring, respectively, the first and second pluralities of detaching fingers in a predetermined reference position, in particular before that the displacement group is adapted to displace the support body between the assembled position and the disassembled position. In this way, it is ensured that at the moment of positioning a new support body on the support frame, no interference occurs between the different parts which remain on the support frame, in particular the detaching fingers and the parts that are mounted on the support body.

In particular, in case that the folding or interfolding rolls are provided with counter-blades, in particular integral to the roll, it is avoided that these can interfere with the detaching fingers. Furthermore, in this way, it is possible to speed up the starting operation of the machine once that a support body has been replaced with another. In other words, in this way it is possible to significantly reduce the downtime of the machine necessary to complete the operation.

Advantageously, the aforementioned engagement portions of the support body of the displacement group can be configured to reversibly move from an engagement configuration to a disengagement configuration. In particular, the aforementioned engagement portions of the support body and of the displacement group can be adapted to move from the engagement position to the disengagement position by translating with respect to each other in a first translation direction and from the disengagement position to the engagement position by translating with respect to each other in a second translation direction opposite to the first one.

Advantageously, a separation group can be, furthermore, provided configured to separate a finished stack of folded or interfolded sheets, from a following stack once that a predetermined height of the aforementioned stack to be formed is reached.

In particular, the aforementioned cutting group can comprise a first and a second cutting device provided, respectively, with at least a first and a second cutting blade. More in particular, the first and second cutting devices can be associated, respectively, to the first and second folding or interfolding rolls. These are, advantageously, respectively, provided with a first and a second plurality of counter-blades distributed peripherally to the first and to the second folding or interfolding roll.

Advantageously, the first and second pluralities of counter-blades are configured to operate, respectively, in combination with the first and with the second cutting blades of the cutting device to divide a first and a second web of paper, or similar products, in the first and in the second plurality of sheets.

In particular, the separation group comprises a first and second pluralities of separation members configured to move between a first position and a second position to cause the aforementioned separation of a finished stack from a stack to be formed. More in particular, the first and second pluralities of separation members are configured to move from the first to the second position moving along a respective movement trajectory external to the encumbrance of the first and of the second folding or interfolding roll, in such a way not to intersect the first and second pluralities of counter-blades.

According to a further aspect of the invention, a method for producing packages of folded or interfolded laminar products made of paper material, in particular packages of napkins, tissues, towels, or similar products, comprises the features of claim <NUM>.

In particular, at least a first and a second support body can be provided and wherein are provided the steps of:.

Advantageously, a first and a second plurality of detaching fingers can be, furthermore, provided configured to cause the detachment of the folded or interfolded sheets of paper, respectively from said first and from said second folding or interfolding roll and wherein, furthermore, are provided the steps of:.

In particular, a vacuum distribution device can be, furthermore, provided configured to selectively pneumatically connect a vacuum generation device configured to generate a predetermined vacuum degree to at least one row of the aforementioned plurality of rows of suction holes, at predetermined angular positions of the tubular body, in such a way to cause the first and second pluralities of worked sheets of paper to be sucked and to adhere at predetermined portions of the folding or interfolding roll, said vacuum distribution device and said vacuum generation device being adapted to be pneumatically connected to, or disconnected from, each other by a connection duct comprising:.

The invention will be now illustrated with the following description of an exemplary embodiment thereof, exemplifying but not limitative, with reference to the attached drawings wherein:.

In <FIG>, it is diagrammatically shown a first embodiment provided by the present invention of a machine <NUM> for producing packages of folded or interfolded laminar products made of paper material, in particular packages of napkins, tissues, towels, or similar products.

The machine <NUM> comprises, in particular, a support frame <NUM> configured to support a feeding group <NUM> adapted to feed at least one web of paper <NUM>, preferably a first and a second web of paper 5a and 5b, along a respective predetermined feeding direction 105a and 105b. The machine <NUM> comprises a folding or interfolding group <NUM> equipped with a first and a second folding or interfolding roll <NUM> and <NUM>. A cutting group <NUM> is, furthermore, provided configured to cut the, or each, web of paper <NUM> into a respective plurality of sheets <NUM> of predetermined length. This is determined, in particular, by the diameter of the folding or interfolding rolls <NUM> and <NUM> and, if present, by the diameter of the cutting rolls <NUM> and <NUM> of the cutting group <NUM> as well as by the number of blades <NUM> which are mounted on the same. The folding or interfolding rolls <NUM> and <NUM> are configured to rotate about respective longitudinal rotation axes <NUM> and <NUM> in such a way to be counter-rotating with respect to each other, and to fold or interfold the or each aforementioned plurality of sheets of paper <NUM> at a folding or interfolding zone <NUM>. In this way a stack <NUM> is obtained of sheets which are folded or interfolded according to a predetermined folding or interfolding configuration growing in height along a predetermined forming direction. In particular, the cutting group <NUM> and the folding or interfolding group <NUM> are mounted on the same support body <NUM>. More in particular, the support body <NUM> is configured to move between an assembled position, in which is supported by the support frame <NUM>, and a disassembled position, in which is, instead, not supported by the support frame <NUM>. Preferably, once that the support body <NUM> has been moved to the disassembled position, it can be positioned in a store area <NUM>, for example in order to be subject to ordinary or extraordinary maintenance operations, before being positioned, again, in the machine <NUM>, and precisely on the support frame <NUM>.

According to the present invention, the machine <NUM>, furthermore, comprises a displacement group <NUM> configured to displace the support body <NUM> between the assembled position and the disassembled position. More in detail, the displacement group <NUM> and the support body <NUM> are provided with respective engagement portions <NUM> and <NUM> configured to engage with each other, in particular in a removable way, in such a way to allow the displacement group <NUM> to cause the displacement of the support body <NUM> between the assembled position and the disassembled position with respect to the support frame <NUM>.

Preferably, the displacement group <NUM> is configured to cause the movement of the support body <NUM> from the assembled position to the disassembled position by lifting the same from the support frame <NUM>, and the opposite movement, i.e. from the disassembled position to the assembled position, by lowering the support body on the support frame <NUM>.

Advantageously, the displacement group <NUM> can be configured to displace the support body <NUM> at least along a first displacement direction <NUM>. In particular, the first direction <NUM> can be a direction orthogonal to the longitudinal axes <NUM> and <NUM> of the folding or interfolding rolls <NUM> and <NUM>. More precisely, the first direction <NUM> can be the direction along which the displacement group <NUM> is adapted to cause the aforementioned lifting with respect to the support frame <NUM> to move the support body <NUM> same from the assembled position to the disassembled position, or the aforementioned lowering, to move, instead, the support body <NUM> from the disassembled position to the assembled position. More in particular, the aforementioned displacement group <NUM> can be, furthermore, configured to displace the support body <NUM> along a second displacement direction <NUM>. For example, the aforementioned displacement direction <NUM> can be a direction orthogonal to the first displacement direction <NUM>.

In particular, in the embodiment diagrammatically shown in <FIG>, the cutting group <NUM> can provide a first and a second cutting roll <NUM> and <NUM> associated respectively to the first and to the second folding or interfolding roll, <NUM> and <NUM>. More precisely, the cutting rolls <NUM> and <NUM> can be peripherally provided with a predetermined number of blades, and rotate about respective longitudinal axes to cut and, therefore, to divide, a respective web of paper 5a, 5b into a respective plurality of sheets <NUM> by operating in combination with a respective fixed counter-blade.

In an alternative embodiment provided by the present invention and diagrammatically shown from <FIG>, and in detail in <FIG>, the cutting group <NUM> can be of the type described in <CIT> in the name of the same Applicant. In particular, the cutting group <NUM> can comprise a first and a second fixed cutting device <NUM> and <NUM> respectively associated to the first and to the second folding or interfolding roll <NUM> and <NUM>. More in detail, in this case the first and the second cutting device <NUM> and <NUM> comprises, respectively, a base portion <NUM> provided with at least a cutting blade <NUM>. In this case, the first and second folding or interfolding rolls <NUM> and <NUM> are provided with respective pluralities of counter-blades <NUM> distributed along the respective tubular body. Therefore, the cut of each web 5a, or 5b, in a respective plurality of sheets <NUM> is carried out directly on the folding or interfolding rolls <NUM> and <NUM> which then provide to fold or interfold the sheets <NUM> same according to a predetermined folding or interfolding configuration. In particular, the folding or interfolding rolls, <NUM> and <NUM> can be also peripherally provided with recesses <NUM>' and the aforementioned counter-blades <NUM> alternating to each other, in such a way to avoid that at the folding zone <NUM> the counter-blades <NUM> of a roll <NUM> or <NUM> can compromise the folding or interfolding operation and/or cut the worked sheets <NUM>.

As diagrammatically shown for example in the <FIG> and <FIG>, for the two types of cutting group <NUM> described above, in a possible embodiment of the invention, the displacement group <NUM> can provide a first guide member <NUM> oriented along the first displacement direction <NUM>, and, advantageously, a second guide member <NUM> oriented along a second displacement direction orthogonal to the aforementioned first displacement direction <NUM>. In particular, the first guide member <NUM> can be mounted on a support member <NUM>. This latter can be configured to slide along the second guide member <NUM>. In particular, the support member <NUM> can comprise a base portion <NUM> and a sliding portion <NUM> configured to slide with respect to the base portion <NUM> along the aforementioned first guide member <NUM>. More in particular, the sliding portion <NUM> can be provided with the engagement portion <NUM> configured to engage the respective engagement portion <NUM> of the support body <NUM>.

In the example that is diagrammatically shown in the figures from <NUM> to <NUM>, the displacement group <NUM> provides a first and a second support member <NUM> provided with respective engagement portions <NUM> adapted to engage respective engagement portions <NUM> at opposite ends <NUM> and <NUM>. For example, the or each engagement portion <NUM> can be a shelf protruding from the sliding portion <NUM> and the or each engagement portion <NUM> of the support body <NUM> can be a portion which protrudes longitudinally to the support body <NUM>. In this way, in order to lift the support body <NUM>, it is possible to position the engagement portion <NUM> below the engagement portion <NUM> and, then, to move upward the sliding portion <NUM> along the first displacement direction <NUM>. In other embodiments, the sliding portion <NUM> can be provided with different engagement devices arranged to hook or engage the support body <NUM> to lift and to displace the same from and towards a store area <NUM>, such as, for example, devices for providing a magnetic coupling, for example electromagnets, or a mechanical coupling.

In some embodiments, the support member <NUM> can be configured to slide with respect to a third guide member <NUM> along a third displacement direction <NUM> orthogonal to the first and to the second displacement direction <NUM> and <NUM>. In this way, it is possible to approach or move away the engagement portions <NUM> and <NUM> with respect to each other to cause them to move from the disengagement position shown in the <FIG>, to the engagement position shown in the <FIG>, and vice versa. In general, the displacement group <NUM> can be a manipulator having at least two degrees of freedom. In preferred embodiments the two degrees of freedom are orthogonal to each other, but the possibility is also foreseen that the displacement group <NUM> can be configured to cause the movement of the support body <NUM> from the assembled position to the disassembled position, or vice versa, by a combination of movements comprising at least one translation and at least one rotation. For example, in a solution that is not shown in figure for simplicity, the support member <NUM> can be adapted to move along the second guide member <NUM> and to be provided with two swinging arms, i.e. rotatably mounted on support member <NUM> and able to engage the support body <NUM> to lift the same from the support frame <NUM>.

As diagrammatically shown for example in <FIG> the support member <NUM> can be configured to move, in particular integrally to the third guide member <NUM>, with respect to the second guide member <NUM>. In this way, it is possible to move the support member <NUM> and, therefore, the support body <NUM> that is supported by it, between a working area <NUM> and a store area <NUM>. More in particular, within the store area <NUM> at least a second support body 110b can be positioned that have different characteristics, in particular in terms of size, with respect to the folding or interfolding group <NUM> and to the cutting members <NUM>, in particular folding rolls 31b and 32b having a diameter different from the folding rolls 31a and 32a of a first support body 110a positioned within the working area <NUM>, i.e. in the assembled position with respect to the support frame <NUM>.

In this way, if a production change is requested, for example in terms of length of the panel and/or the sheet <NUM>, it is sufficient to operate the displacement group <NUM> in order to carry out the operations that are diagrammatically shown in the figures from <NUM> to <NUM> to remove the support body 110a arranged in the assembled position that means on the support frame <NUM>, to its positioning, which is carried out again by the displacement group <NUM>, inside the store area <NUM>, to the picking up from the store area <NUM> of another support body, for example the support body 110b, and its positioning on the support frame <NUM> in the assembled position. In particular, within the store area <NUM> at least a free position can be provided at which the support body <NUM> picked up at the assembled position can be positioned. According to the present invention, the store area <NUM> and the working area <NUM> can be approached by at least one worker <NUM>, advantageously through independent accesses <NUM> and <NUM>, respectively. In this way, it is possible for the worker <NUM> to easily and quickly reach the aforementioned areas and any support body <NUM> that is in case positioned there in order to carry out ordinary or extraordinary maintenance operations. In particular, whilst the paper converting line comprising the machine <NUM> is normally working, a worker can enter the store area <NUM> to carry out the maintenance operations on the support bodies <NUM> comprising the folding or interfolding group <NUM> and, if present, the cutting group <NUM>.

In particular, the displacement group <NUM> can be configured to alternately and selectively bring a first support body 110a in the disassembled position from the assembled position, and a second support body 110b from the disassembled position in the assembled position.

As diagrammatically shown in <FIG>, each of the folding or interfolding rolls <NUM> and <NUM> can comprise a tubular body <NUM> configured to rotate about a respective longitudinal rotation axis <NUM> and <NUM>. The tubular body <NUM> is provided with a plurality of suction holes <NUM> organized in a plurality of couples of longitudinal rows close to each other. A vacuum distribution device <NUM> can be, furthermore, provided that will not be described here in detail, but, for example, of the type that is described in <CIT> or <CIT>, both in the name of the present Applicant. In particular, the vacuum distribution device <NUM> is configured to selectively pneumatically connect at least a vacuum generation device <NUM> to at least a row at a time of the aforementioned plurality of rows of suction holes <NUM>, at predetermined angular positions of the tubular body <NUM>, in such a way to cause the worked sheets of paper <NUM> to be sucked and to adhere at predetermined portions of the folding or interfolding roll <NUM> or <NUM>.

According to the present invention, the vacuum distribution device and the or each vacuum generation device <NUM> are pneumatically connected to each other by a connection duct <NUM>. This, as diagrammatically shown in <FIG>, can comprise a first portion <NUM> integral to the vacuum distribution device <NUM> and a second portion <NUM>, in particular a second portion <NUM> associated to each folding or interfolding roll <NUM> and <NUM>, integral to the vacuum generation device <NUM>.

In particular, as diagrammatically shown in the figures from <NUM> to <NUM>, the first and second portions <NUM> and <NUM> can be adapted to move between a connection configuration (<FIG>), in which are adapted to pneumatically connect the vacuum generation device <NUM> to the vacuum distribution device <NUM>, and a disconnection configuration (<FIG>), in which are adapted to pneumatically disconnect the vacuum distribution device <NUM> and the vacuum generation device <NUM>. More in particular, the connection duct <NUM> can, furthermore, comprise a third portion <NUM> configured to move from a connection position (<FIG>) in which is adapted to pneumatically connect the first and the second portion of the connection duct <NUM> and <NUM> to each other that are, therefore, arranged in the connection configuration, and a disconnection position in which is adapted to pneumatically disconnect the first and second connection portions <NUM> and <NUM>, which are, therefore, arranged in the aforementioned disconnection configuration.

As diagrammatically shown in the figures from <NUM> to <NUM>, the third portion <NUM> can be slidingly mounted with respect to the first and second portions <NUM> and <NUM> of the connection duct <NUM> between the connection position, where is arranged in an advanced position, and the disconnection position, where is arranged in a retracted position. More in detail, at least one sealing element <NUM>, for example an O-ring, positioned between the third portion <NUM> and the first and/or the second portion <NUM> and/or <NUM>.

In particular, the or each sealing element <NUM> can be configured to move from a working configuration, in which is adapted to exert a sealing action to pneumatically isolate the first and second portions <NUM> and <NUM> of the connection duct <NUM> from the external environment (<FIG>), and a rest configuration in which is not adapted to exert the aforementioned sealing action (<FIG>). For example, the or each sealing element <NUM> can be pneumatically connected to an inflating device, which is not shown in figure for simplicity, adapted to cause the movement from the rest configuration to the working configuration, in particular by introducing air, or another gas, into each sealing element. In particular, in an embodiment provided by the invention, it is possible to cause the third portion <NUM> to slide from the connection position to the disconnection position and vice versa, when the or each sealing element <NUM> is in the rest configuration. More in particular, when the or each sealing element <NUM> is arranged in the working configuration, it can be adapted to prevent, or obstruct, the third portion <NUM> from sliding.

Advantageously, as diagrammatically shown in <FIG>, the machine <NUM> comprises, furthermore, a motor group <NUM> configured to cause at least one between the first and second folding or interfolding rolls <NUM> and <NUM> to rotate about the respective rotation axis <NUM> and <NUM>. In particular, the motor group <NUM> can be configured to operate the aforementioned rotation by a main motor <NUM> and a motion transmission device <NUM> configured to transmit the rotational motion of the rotation shaft, which is not shown in figure for simplicity, of the main motor <NUM> to at least one between the first and second folding or interfolding rolls <NUM> and <NUM>.

In particular, the motion transmission device <NUM> can comprise a first transmission member <NUM>, for example a first toothed belt <NUM>. As diagrammatically shown in the <FIG> and <FIG>, the first transmission member <NUM> can mesh with a main deflection wheel <NUM> in such a way to cause it to rotate about a rotation axis <NUM>. In particular, the motion transmission device <NUM> can comprise, furthermore, a rotation shaft <NUM> coaxially arranged to the main deflection wheel <NUM> and integral to it. Therefore, the aforementioned rotational motion of the main deflection wheel <NUM> causes also the rotation shaft <NUM> to rotate about the rotation axis <NUM>. More in particular, the motion transmission device <NUM> can comprise, furthermore, at least a second motion transmission member, for example a second toothed belt <NUM>, which is mounted on the aforementioned rotation shaft <NUM> and on a series of guide pulleys <NUM> defining a predetermined sliding path. More in detail, the second motion transmission member <NUM>, is adapted to mesh with a motion transmission portion <NUM> integral to the first, or second folding or interfolding roll, <NUM> or <NUM>, in such a way to cause a rotation about the respective longitudinal rotation axis <NUM> or <NUM>. Preferably, the first and second folding or interfolding rolls <NUM> and <NUM> can be operatively connected with each other by respective gears, for example toothed wheels coaxially arranged to the rolls <NUM> and <NUM> and that are not shown in the figure for simplicity, in such a way that the rotations of the same about the respective rotation axes <NUM> and <NUM> are synchronized and occur in directions of rotation opposite to each other.

Advantageously, a group for adjusting the tension <NUM> is, furthermore, provided configured to adjust the tension of the motion transmission device <NUM>, in particular the tension acting on the first and/or on the second motion transmission member <NUM> and/or <NUM>.

In particular, the group for adjusting the tension <NUM> can be configured to keep constant, or substantially constant, the tension of the motion transmission device <NUM>, preferably of the second transmission member <NUM>, in particular during the movement of the support body <NUM> between the assembled position and the disassembled position carried out by the displacement group <NUM>. In this way, it is possible to ensure that during the replacement of a support body <NUM>, for example of the support body 110a with the support body 110b, the second motion transmission member <NUM>, in particular the toothed belt, is correctly positioned with respect to the different movable parts remaining on the support frame <NUM>. Therefore, it is ensured that the different parts of the machine <NUM> are able to correctly work when the machine <NUM> is operated again and arranged in working conditions.

In an alternative embodiment not shown in the figure for simplicity, the transmission of the motion of the motor shaft of the main motor <NUM> to the rotation shaft <NUM> can be obtained by using as motor shaft <NUM> the motor shaft of the main motor <NUM>, i.e. mounting the same coaxially to the rotation axis <NUM>.

In an embodiment of the invention, the group for adjusting the tension <NUM> comprises a measurement device <NUM>, for example a force sensor, such as a load cell, advantageously configured to measure the tension on the second motion transmission member <NUM>.

In particular, the measurement device <NUM> can be operatively connected to a processing device <NUM> configured to operate an actuation device <NUM>. More in particular, the actuation device <NUM> can be configured to cause a lengthening or a shortening of the path of the motion transmission member <NUM> depending on the tension signal detected by the aforementioned measurement device <NUM>. More in detail, the motion transmission belt <NUM> can be mounted on a series of guide pulleys or rollers <NUM> and <NUM> at least one of which able to move along a predetermined direction. For example, the transmission belt <NUM> can be mounted on a series of fixed guide pulleys <NUM> and on at least one movable guide pulley <NUM>, for example on two movable guide pulleys <NUM>. In particular, the actuation device <NUM> can be arranged to lengthen or to shorten the path of the transmission belt <NUM> thus causing the or each movable guide pulley <NUM> to move away from the fixed guide pulleys <NUM>. As diagrammatically shown in the <FIG> and <FIG>, the actuation device <NUM> can comprise a motor <NUM> configured to cause the or each movable guide pulley <NUM> to move along a predetermined actuation direction <NUM> by an actuation device <NUM>. In practice, during the replacement of a support body <NUM>, the tension of the transmission belt <NUM> tends to gradually reduce that the aforementioned support body <NUM> is lifted and, therefore, progressively disengaged from the transmission belt <NUM>. During this step, the group for adjusting the tension <NUM> can be operated by the processing device <NUM> to keep the tension of the transmission belt <NUM> constant or substantially constant, by operating the actuation device <NUM>. Analogously, the tension of the transmission belt <NUM> tends to increase during the positioning of a new support body <NUM> which engages with the motion transmission portion <NUM> of one between the folding or interfolding rolls <NUM> and <NUM>. Also in this step the group for adjusting the tension <NUM> can be operated by the processing device <NUM> to keep constant the tension of the transmission belt <NUM>.

Advantageously, the tension adjustment device <NUM> can be used also during the normal working conditions of the machine <NUM> to keep the transmission belt <NUM> constantly at a determined correct working tension. In this way both overloads and loosening, which could cause the loss of phase between the folding rolls <NUM> and <NUM> with other components of the machine <NUM> exposing to the risk of jamming, are avoided, or malfunctions in general that in the worst cases can cause the machine <NUM> to be damaged.

As diagrammatically shown in <FIG>, the machine <NUM> according to the invention, can comprise, furthermore, a first and a second plurality of detaching fingers 85a and 85b configured to cause respectively the detachment of the folded or interfolded sheets of paper <NUM>, from the first and second folding or interfolding roll <NUM> and <NUM>, in particular from their external lateral surface.

In particular, a first and a second driving group 80a and 80b are provided configured, respectively, to cause a oscillatory back and forth motion of the first and second pluralities of detaching fingers 85a and 85b towards the or from the folding or interfolding zone <NUM>, in such a way to cause the detachment of the sheets of paper <NUM>, respectively, from the first and second folding or interfolding roll <NUM> and <NUM>. More in particular, the first and second driving groups 80a and 80b can be configured to convert the rotational motion of a motor, or of a respective motor, in an oscillatory back and forth motion that is transmitted to the first and second pluralities of detaching fingers 85a and 85b. In some preferred embodiments of the invention, a transmission device can be provided operated by a main motor <NUM>, not shown in the figure, configured to cause the first and second driving groups 80a and 80b to rotate and that is, therefore, converted in an oscillatory motion.

Advantageously, the first and second driving groups 80a and 80b can be configured to bring, respectively, the first and second pluralities of detaching fingers 85a and 85b in a predetermined reference position, preferably corresponding to the position of top dead centre of the detaching fingers 85a and 85b during the respective back and forth motion. In particular, the reference position can be a position where the detaching fingers 85a and 85b do not have mechanical interference with other components of machine <NUM>, in particular with the folding or interfolding rolls <NUM> and <NUM> and with the cutting blades <NUM>. Advantageously, the first and second driving groups 80a and 80b are arranged to move, respectively, the first and second pluralities of detaching fingers 85a and 85b in the reference position before that the displacement group <NUM> is arranged to move the support body <NUM> between the assembled position and the disassembled position. In this way, it is ensured that, at the moment of positioning a new support body <NUM> on the support frame <NUM>, no interference occurs between the different parts of the machine <NUM>, which remain on the support frame <NUM> and the parts that are mounted on the support body <NUM>, in particular between the detaching fingers 85a and 85b and the cutting blades <NUM> distributed along the folding or interfolding rolls <NUM> and <NUM>, in the case that the cutting group <NUM> is of the type described above with reference to <FIG>.

In particular, according to the present invention, the first and second driving groups 80a and 80b can be configured to delay or anticipate the oscillatory motion of the first and second pluralities of detaching fingers 85a and 85b with respect to a predetermined reference oscillatory motion. In this way, it is possible to delay or anticipate the instant (tr) at which the first and second pluralities of detaching fingers 85a and 85b are arranged to cause the detachment of the sheets of paper <NUM> folded or interfolded, respectively from the first and the second folding or interfolding roll <NUM> and <NUM>. This particular technical solution allows to adjust the motion of the detaching fingers 85a and 85b on the basis of the type of support body <NUM> installed in the machine <NUM>, in particular of the diameter of the folding or interfolding rolls <NUM> and <NUM>, of the number of blades <NUM> of which they are, in case, provided with, and of the other parameters of the cutting group <NUM> and/or of the folding or interfolding group <NUM> installed on the support body <NUM> arranged in the assembled position.

In the embodiment diagrammatically shown in <FIG>, the first and second driving groups 80a and 80b can be, advantageously, associated, respectively, to a first and a second phase adjustment device 90a and 90b configured to adjust the phase of the first and second pluralities of detaching fingers 85a and 85b with the respective folding or interfolding rolls <NUM> and <NUM>. In particular, the first and the second phase adjustment device 90a and 90b are adapted to anticipate, or postpone, the instant tr at which the first and second pluralities of detaching fingers 85a, 85b are adapted to hit the web or sheet of paper to cause it to be detached from the respective folding or interfolding roll <NUM> and <NUM>.

Advantageously, the first and second phase adjustment devices 90a and 90b can comprise, respectively, a first and a second epicycloidal gear 95a, and 95b. More precisely, in this case, the first and second epicycloidal gear 95a and 95b can be operatively connected respectively to a first and a second motor group 91a and 91b, for example by a first transmission belt 87a, and 87b, and to a first and a second driving device 92a and 92b by a second transmission belt 88a and 88b. More precisely, the first and second driving device 92a and 92b are adapted to transmit the rotational motion generated by the first and second motor groups 91a and 91b, respectively to the first and to the second driving group 80a and 80b. The first and second epicycloidal gears 95a and 95b are, respectively, provided with a first and a second electric motor 96a and 96b. These are adapted to adjust the velocity of rotation of the first and of the second driving device 92a and 92b adjusting the velocity and the direction of rotation of a first and of a second epicycloidal gear, not shown in the figure for simplicity, housed, respectively, within the first and the second epicycloidal gear 95a and 95b.

According to a possible functioning mode provided by the invention, the first and second electric motors 96a and 96b can be normally still in such a way not to change the phase of the detaching fingers 85a and 85b with respect to the other parts of the machine <NUM>, in particular the folding rolls <NUM> and <NUM>. If it is necessary to change the phase of the first and of the second plurality of detaching fingers 85a and 85b, for example as a consequence of the replacement of a support body <NUM> with another, the first and the second electric motors 96a and 96b are operated to actuate, respectively, the first and second epicycloidal gears in such a way to temporarily accelerate or decelerate the second transmission belt 88a and 88b. In this way, it is possible to introduce a delay, or an advance, in the oscillatory motion of the first and second pluralities of detaching fingers 85a and 85b and, therefore, to postpone, or anticipate, the instant at which the web or sheet of paper is released by the respective folding or interfolding roll <NUM> and <NUM>, i.e. the instant tr at which the first and second pluralities of detaching fingers 85a and 85b are adapted to cause the web or sheet of paper <NUM> to be detached from the respective folding or interfolding roll <NUM> and <NUM>, in particular with respect to a reference detaching instant tr*. In particular, maintaining still the first and the second motor group 91a and 91b and operating the first and the second electric motor 96a and 96b, it is possible to move the detaching fingers 85a and 85b with respect to the respective folding or interfolding rolls <NUM> and <NUM>. In this way when it is necessary to replace a support body <NUM> with another, it is possible to move the detaching fingers 85a and 85b in the reference position maintaining the folding or interfolding rolls <NUM> and <NUM> still. Once that the reference position has been reached, it is possible to start the replacement of the support body <NUM>.

In a possible embodiment of the invention that is diagrammatically shown in <FIG>, the first and second driving groups 80a and 80b can be configured to translate one with respect to the other in order to approach or move away with respect to each other. In this way, it is possible to adjust the distance between them and in particular the distance with respect to the respective folding or interfolding rolls <NUM> and <NUM>, in case that a support body <NUM> is replaced with another support body <NUM> equipped with folding or interfolding rolls <NUM> and <NUM> having a very different diameter with respect to the previous. In particular, the first and second driving groups 80a and 80b can be slidingly mounted along a predetermined sliding direction <NUM>, in particular orthogonal to the axed <NUM> and <NUM> of the folding or interfolding rolls <NUM> and <NUM>. More in particular, the first and second driving groups 80a and 80b can be mounted on a sliding group <NUM> configured to symmetrically approach or move away with respect to a plane of symmetry of the folding or interfolding rolls <NUM> and <NUM>. For example, the first and second driving groups 80a and 80b can be mounted on a slide <NUM> arranged along the aforementioned sliding direction <NUM>. In particular, a first and a second motor device 182a and 182b can be provided operatively connected, respectively, to the first and to the second driving group 80a and 80b by a respective connection member 183a and 183b. In this way, it is possible to approach or move away by the first and second connection members 183a and 183b, for example an actuation rod, the first and the second driving group 80a and 80b by operating, correspondingly, the first and second motor devices 182a and 182b. However, it is also possible that only one motor device <NUM> is provided configured to symmetrically move through a connection device <NUM> the first and second driving groups 80a and 80b.

In particular, according to a possible sequence of steps provided by the invention, at the moment of replacing a first support body 110a with a second support body 110b, a step of positioning the detaching fingers 85a and 85b in a reference position can be provided. The displacement group <NUM> can be, then, operated in such a way to engage the first support body 110a to be replaced at respective engagement portions <NUM> and <NUM>.

Advantageously, for example with reference to the figures from <NUM> to <NUM>, the engagement portions <NUM> and <NUM> can be provided with respective contacting surfaces <NUM> and <NUM>. In particular, the engagement portions <NUM> and <NUM> can be provided, respectively, with at least a first contacting surface <NUM> and with at least a second contacting surface <NUM>. More precisely, the aforementioned contacting surfaces <NUM> and <NUM> of the engagement portions <NUM> and <NUM>, during the displacement between the assembled position and the disassembled position, in particular when are arranged in the engagement configuration, are positioned in contact with each other (<FIG>). In the case that is diagrammatically shown as an example in the figures from <NUM> to <NUM> each engagement portion <NUM> and <NUM> is provided with <NUM> contacting surfaces <NUM> and <NUM>.

In particular, the engagement portions <NUM> and <NUM> can be configured in such a way that during the movement from the assembled position to the disassembled position and vice versa, no relative motion occurs between the aforementioned respective contacting surfaces <NUM> and <NUM>, or, however, there is no significant relative motion, that means excluding relative motion due to vibrations, or stresses, produced on the same during the displacement by the displacement group <NUM>.

For example, at the engagement configuration the contacting surface <NUM> of the engagement portion <NUM> is adapted to be in contact, for example to lay above, with the contacting surface <NUM> of the engagement portion <NUM> of the displacement group <NUM>.

In particular, still as diagrammatically shown in the figures from <NUM> to <NUM>, the engagement portion <NUM> can provide a portion protruding from the sliding portion <NUM>, advantageously orthogonal to this. More precisely, the engagement portion <NUM> protruding from the sliding portion <NUM> can be configured to laterally contain an end portion <NUM>' of the engagement portion <NUM>, for example substantially flat. For example, the engagement portion <NUM> can be substantially "U-shaped" or "V-shaped". Preferably, a first and a second lateral wall <NUM>'a and <NUM>'b are adapted to laterally contain the engagement portion <NUM> at least at the aforementioned end portion <NUM>' during the displacement between the assembled position and the disassembled position, in particular during the lifting or the lowering of the support body <NUM> with respect to the support frame <NUM> (see <FIG>).

Advantageously, the engagement portions <NUM> and <NUM> can be configured to interlock with each other.

Therefore, the first support body 110a once engaged can be displaced by the displacement group <NUM> at the store area <NUM> where is positioned at a determined storing position 132a. Then, the displacement group <NUM> engages a second support body 110b, in particular positioned at a corresponding storing position. The second support body 110b is, therefore, displaced by the displacement group <NUM> at the working area <NUM>, and, then, positioned on the support frame <NUM>. Once that the second support body 110b has been moved in the assembled position, the detaching fingers 85a and 85b are, then, moved from the reference position to the working position in order to start a new production cycle.

In an alternative embodiment provided by the invention, if the connection duct <NUM> is of the type described above with reference to the figures from <NUM> to <NUM>, the steps can be, furthermore, provided of positioning the aforementioned first and second portions <NUM> and <NUM> in the disconnection configuration, before displacing by the displacement group <NUM> the first support body 110a from the working area <NUM> to the store area <NUM>. Advantageously, once that the second support body 110b has been positioned, by the displacement group <NUM>, at the working position <NUM>, the first and second portions <NUM> and <NUM> of the connection duct <NUM> are arranged in the connection configuration.

The aforementioned step of engaging by the engagement portions the displacement group <NUM> and the support body <NUM> and of positioning the first and second portions <NUM> and <NUM> of the connection duct <NUM> in the disconnection position, can be carried out simultaneously, or one before the other. The same can be said for the steps of positioning the first and second portions <NUM> and <NUM> of the connection duct <NUM> in the connection position and the positioning of the detaching fingers 85a and 85b from the reference position to the working position. In an alternative embodiment of the invention, a step can be provided of approaching or moving the detaching fingers 85a and 85b away with respect to each other, before displacing the support body 110a by the displacement group <NUM> to the store area <NUM>. In this case, a step can be also provided of repositioning the detaching fingers 85a and 85b with respect to the folding or interfolding rolls <NUM> and <NUM> in a predetermined position before positioning the detaching fingers 85a and 85b in the working position. Advantageously, all the aforementioned steps, or at least a part of these, can be automatically managed, operated and controlled by the processing device <NUM>.

Once that the new support body <NUM> has been positioned on the support frame <NUM>, it is possible to block it by blocking devices in such a way to constrain their relative position. The blocking devices are not shown in the figure for simplicity. In some cases, during the replacement of a support body <NUM> with another, among the steps, it is possible to carry out a further step of positioning the folding or interfolding rolls <NUM> and <NUM> in a predetermined reference position, or a position zero. This further step can be particularly necessary in case that the folding or interfolding rolls <NUM> and <NUM> have the cutting blades <NUM> on board. In the case that the support body <NUM> comprises both the folding or interfolding group <NUM> and the cutting group <NUM>, this further step can be omitted.

In an alternative embodiment provided by the invention and diagrammatically shown in <FIG>, the displacement group <NUM> comprises a first and a second support member 55a and 55b, advantageously, slidingly mounted on the same second guide member <NUM>. In particular, each support member 55a and 55b can be configured to be positioned between a picking up position, at which is adapted to pick a respective support body <NUM> up, at the working area <NUM> or store area <NUM>, and a waiting position, at which are adapted to engage outside the working area <NUM> and the store area <NUM>, the support body <NUM> at the working area <NUM>, or the store area <NUM>, and then releasing the same at the store area <NUM>, or the working area <NUM>, where the aforementioned displacement of the support body <NUM> from the assembled position to the disassembled position can be carried out.

Claim 1:
Machine (<NUM>) for producing packages of folded or interfolded laminar products made of paper material, in particular packages of napkins, tissues, towels, or similar products, said machine (<NUM>) comprising a support frame (<NUM>) configured to support:
- a feeding group (<NUM>) configured to feed a first and a second web of paper (5a,5b) respectively along a first and a second predetermined feeding direction (105a, 105b);
- a cutting group (<NUM>) configured to cut said first and second webs of paper (5a,5b), respectively, into a first and a second plurality of sheets of paper (<NUM>) of predetermined length;
- a folding or interfolding group (<NUM>) equipped with a first and a second counter-rotating folding roll (<NUM>,<NUM>) adapted to rotate about respective longitudinal rotation axes (<NUM>,<NUM>) and configured to fold or interfold said first and second pluralities of sheets of paper (<NUM>) at a folding or interfolding zone, (<NUM>) in such a way to obtain a stack (<NUM>) of sheets folded or interfolded according to a predetermined folding or interfolding configuration, said cutting group (<NUM>) and said folding or interfolding group (<NUM>) being mounted on a same support body (<NUM>) configured to move between an assembled position in which is adapted to be supported by said support frame (<NUM>), and a disassembled position, in which is not adapted to be supported by said support frame (<NUM>);
- a displacement group (<NUM>) configured to displace said support body (<NUM>) between said assembled position and said disassembled position;
said machine (<NUM>) being characterized in that said displacement group (<NUM>) is configured to displace said support body (<NUM>) from said assembled position to said disassembled position by lifting said support body (<NUM>) from said support frame (<NUM>), and to displace said support body (<NUM>) from said disassembled position to said assembled position by lowering said support body (<NUM>) on said support frame (<NUM>), and in that said displacement group (<NUM>) and said support body (<NUM>) are provided with respective engagement portions (<NUM>,<NUM>) configured to engage with each other in such a way to allow said displacement group (<NUM>) to displace said support body (<NUM>) between said assembled position and said disassembled position with respect to said support frame (<NUM>).