|
(11) | EP 1 988 041 A2 |
| (12) | EUROPEAN PATENT APPLICATION |
|
|
|
|
|||||||||||||||||||||||
| (54) | Rewinding machine for rewinding and forming a paper roll |
| (57) A rewinding machine for rewinding and forming a paper roll comprising three rollers
(16,17,18) with axis parallel to each other and perpendicular to the direction of
forward movement of the paper, wherein the two upper and lower winding rollers (16,17)
cooperate with a third roller (18), adapted to keep a given pressure on a roll, or
log, to form a finished roll by winding of the paper, which passes on the upper winding
roller (16), around a core (12), an introduction group (13) of the cores (12) one
after the other into a channel (24) provided beneath the upper roller (16), and a
paper stop group (120) which cooperates with at least one first surface portion (16',16")
of the upper roller (16) rotating around a pin (128), wherein the stop group (120)
comprises at least one paper stop element (120',120") provided with an arm (132',132")
rotating around the pin (128) and with a free end made up of a smooth surface (133',133"),
and in which the at least one first surface portion (16',16") of the upper roller
(16) is smooth and provided with a plurality of air suctioning holes (101).
|
[0001] The present invention refers to an improved rewinding machine for rewinding and forming a paper roll.
[0002] Machines or treatment groups for winding paper intended for domestic use, in particular paper used for purposes such as toilet paper, kitchen rolls, and the like, known today, comprise elements which guide the paper being delivered and they control their proper winding on a core in order to provide a finished roll referred to as a "log".
[0003] These machines, called rewinding machines, are provided with two winding rollers and a third pressure roller.
[0004] The first two rollers determine the winding of the paper around a roller as the diameter increases while the third roller, alongside cooperating in such winding operation, keeps a given pressure on the roll or log ensuring its proper and perfectly compact winding.
[0005] The two rollers are arranged at a fixed position with respect to the framework and support the log, drawing the paper.
[0006] One of the two abovementioned winding rollers, especially the one arranged at a higher position which receives the paper first, to firmly hold the same and draw it during the rotation, currently has a "furrowed" external surface provided with a plurality of parallel circular bands made of high friction material.
[0007] Such bands are separated from each other by other parallel circular bands made of other material, generally low friction material.
[0008] When it comes, in due time, to breaking the paper, currently provided are stop and breaking means of the same which cooperate with the abovementioned "furrowed" upper winding roller on which the paper is wound.
[0009] In particular, such stop means cooperate in breaking the paper by exerting pressure against the "furrowed" surface of the roller.
[0010] Nowadays, such paper stop and breaking means, given that as mentioned they operate against the external "furrowed" surface of the upper roller provided with a plurality of parallel circular bands made of friction material separated from each other by parallel circular bands made of other material, are also "furrowed" in a corresponding manner.
[0011] In particular, they are provided with a plurality of parallel cavities separated from each other by parallel portions with an outwards projecting profile.
[0012] The projecting parallel portions are arranged in such a manner to operate against the upper roller at the parallel circular bands of material made of non-friction material while the remaining circular bands with high friction of the same roller are provided at the abovementioned parallel cavities.
[0013] In such manner, there is no contact between the high friction circular bands of the roller and the related stop and breaking means of the paper.
[0014] Such pairing is required given that should contact occur even at the high friction circular bands of the roller, right due to the locally present high friction, inadvertent breaking of the paper might occur at such points, as well as greater wear of such high friction bands.
[0015] However, current known machines for rewinding and winding a paper roll and provided with such rollers and such paper stop and breaking means have various drawbacks.
[0016] Observable among them is the high production cost of both the "furrowed" winding rollers, due to the presence of a plurality of parallel circular bands made of high friction material, and due to the paper stop and breaking means which, being "furrowed", imply high production costs linked to the removal of material to provide the cavities of dimensions corresponding to the circular friction bands of the related roller.
[0017] Another disadvantage linked to such pairing between a "furrowed" roller and the corresponding "furrowed" paper stop and breaking means lies in the fact that, given the presence of a small and discontinuous relative contact surface between the two elements, the braking step which leads to the ripping requires long periods of time which weigh negatively over the subsequent winding step of the tip of the paper just previously ripped onto a new core introduced into the machine.
[0018] Lastly, disadvantageously, such machines do not provide for the possibility to rip the types of paper of greater thickness/resistance with respect to the ones used currently.
[0019] The objective of the present invention is that of providing a device capable of overcoming the abovementioned drawbacks of the known art in an extremely simple, inexpensive and particularly functional manner.
[0020] Another objective is that of providing an improved rewinding machine for rewinding and forming a paper roll, capable of reducing the period of time required during the braking step which leads to ripping the paper.
[0021] Still another objective is that of providing an improved rewinding machine for rewinding and forming a paper roll, capable of ensuring better winding of the tip of the ripped paper onto a related new core.
[0022] Still another objective is that of providing an improved rewinding machine for rewinding and forming a paper roll, capable of ensuring ripping also the types of paper of greater thickness/resistance with respect to ones used currently.
[0023] These objectives according to the present invention are attained by means of an improved rewinding machine for rewinding and forming a paper roll as described in claim 1.
[0025] Characteristics and advantages of an improved rewinding machine for rewinding and forming a paper roll according to the present invention shall be clearer from the following exemplifying and non-limiting description with reference to the attached schematic drawings wherein:
Figure 1 is a perspective schematic view of an embodiment of an improved rewinding machine for rewinding and forming a paper roll according to the present invention;
Figure 2 is an enlarged top view of some details of the rewinding machine of figure 1; and
Figure 3 is a partially broken away perspective schematic view of another embodiment of an improved rewinding machine for rewinding and forming a paper roll according to the present invention.
[0026] First referring to figure 1, shown is an improved rewinding machine for rewinding and forming a paper roll, in particular paper subsequently used as toilet paper, kitchen rolls, and the like, in which shown is the arrangement for rewinding and winding a paper roll according to the invention. The supplied paper is of the type made of one or more layers combined to each other, once unrolled from their respective rolls, not shown.
[0027] This paper as layer is delivered from a large roll (not shown) and it should be wound on a tubular core 12.
[0028] Such machine, as shown in figure 1, comprises three rollers 16, 17 and 18 with axis parallel to each other and perpendicular to the direction of advancement of the paper, not shown, generally supplied vertically above the roller 16.
[0029] The two rollers 16 and 17, respectively for upper and lower winding, cooperate with the third roller 18 to form a finished roll, which exits from the machine through an exit opening 30 provided between the lower winding rollers 17 and the third roller 18.
[0030] The latter, said "pressure roller", keeps a given pressure on the roll or log being formed, ensuring its proper winding and it is supported on opposite ends by at least a pair of arms 22, one of which is schematically shown in figure 1 alongside a related pin 23.
[0031] Furthermore, the roller 18 can be subjected to pressure control through a sensor or a similar element (not shown).
[0032] Additionally, the machine comprises an introduction group 13 which introduces the cores 12 one after the other into a channel 24 provided beneath the upper roller 16 where proper winding of the paper on each core 12 is controlled to provide a finished roll, of a preset size, usually referred to as a "log".
[0033] The channel 24 is provided with curved elements or cradles 25, arranged adjacent to each other, only one of which is shown, adapted to be at least partially inserted through their ends into grooves 26 provided on the external surface of the of the lower roller 17. However, the lower roller 17 could also be smooth and such curved elements are laid against its surface in this case.
[0034] In order to provide for ripping the paper, the machine comprises a step group 120 of the paper itself, which cooperates with at least one first surface portion 16', 16" of the upper roller 16 on which it operates rotating around a pin 128 parallel to the axis of the roller 16.
[0035] In such manner, the stop group 120, which blocks the paper operating on the portions 16', 16" of roller 16, intervenes on the paper wound and moved forward on the roller 16.
[0036] According to the invention, the stop group 120 can be positioned upstream of the channel 24, as shown in figure 1, or alternatively inside the same channel 24, as shown in figure 3.
[0037] Ripping of the paper occurs in proximity to the perforation due to the blocking of the same against the upper roller 16 by the stop group 120.
[0038] Subsequently to this ripping direct winding of the tip of the paper onto the new core 12 inside the channel 24 occurs.
[0039] According to the invention, the stop group 120 comprises at least one stop element 120', 120" of the paper moved forward wound on the roller 16.
[0040] Each stop element 120', 120" is provided with an arm 132', 132" rotating around the abovementioned pin 128 and with a free end made up of a smooth surface 133', 133''.
[0041] Hence, such smooth surface 133', 133" operates on the related at least one first surface portion 16', 16" of the upper roller 16 which, according to the invention, is smooth and provided with a plurality of air suctioning holes 101 for holding the paper wound onto the upper roller 16 itself.
[0042] Therefore, according to the invention, contact between the roller 16 and the related stop group 120 is a contact between two smooth surfaces and not, as currently known, between two furrowed surfaces.
[0043] It is obviously understood that in such contact the paper wound on such roller 16 is interposed.
[0044] Such pairing between two smooth surfaces leads to the advantage of having a larger contact surface and thus perform an excellent ripping of the paper within very short periods of time, reducing the difference of the peripheral velocity required between the upper roller 16 and the stop group 120, facilitating in such manner the subsequent winding of the tip of the ripped paper on a related new core 12.
[0045] As a matter of fact, the rewinding machine 10 subject of the present invention is implemented with enhanced continuity in the winding process alongside the synchronised highly accurate breaking of the paper in proximity to the perforation.
[0046] Furthermore, being advantageously provided with much larger relative contact surfaces between the roller 16 and the paper stop group 120 with respect to the known art, the machine 10 according to the present invention allows ripping also the types of papers with much more trickiness and/or resistance to ripping with respect to the ones commonly used currently.
[0047] According to the preferred embodiment shown in figure 2 the machine comprises a plurality of the abovementioned stop elements 120', 120" arranged in series one after the other and separated from each other by an interspace.
[0048] At such interspaces, according to the present invention, it is provided for that the surface of the upper roller 16 possibly further comprises at least one second surface portion 116', 116" provided with friction material.
[0049] Advantageously, such friction material present in this at least one second surface portion 116', 116'' of the upper roller 16 is preferably tungsten carbide while the at least first smooth surface portion 16' , 16'' on which the stop group 120 operates with the related smooth surfaces 133', 133" is preferably made of aluminium.
[0050] Alternatively, the at least one first surface portion 16' 16'' of the upper roller 16, or the entire surface of the roller 16 in the absence of the at least one surface second portion 116' 116'' made of friction material, can be made of iron.
[0052] According to the example, shown in figure 1, the introduction group 13 comprises a pusher conveyor 15, upstream of the three rollers 16, 17, 18 for the introduction of the cores 12 into the channel 24 one after the other, and a rotating pusher 35 adapted to move the cores 12 forward along the channel 24.
[0053] Obviously, even the other types of pushers, oscillating or rotating, different from the ones provided for exemplifying and non-limiting purposes could be arranged at the entrance of the channel 24.
[0054] As mentioned previously, the upper roller 16 has at least a suctioning function and it comprises a plurality of longitudinal channels 100 arranged as a circular ring in proximity to its cylindrical surface and arranged connected to the external by means of the already mentioned plurality of holes 101.
[0055] In order to obtain the suctioning effect required, the machine lastly comprises at least a pair of circular section-shaped sliding suctioning elements 102 arranged in axis with respect to the roller 16, fixed and facing the opposite tips adapted to trigger the air suctioning through the channels 100 comprised between them.
[0056] The suctioning of the air through such channels 100, which can be continuous or suitably synchronised with the operation of the rewinding machine, thus involves only one portion of the upper rotating roller 16 where the suctioning sliding elements 102 are provided.
[0057] Given that the upper roller 16 rotates during the air suctioning operation, such suctioning is performed progressively through subsequent channels 100.
[0058] Due to the intervention of the suctioning means, holding of the tip of the paper against the roller 16 is ensured in the fraction transiting subsequently to the ripping of the paper due to the action of the stop group 120.
[0059] According to the preferred embodiment shown in figure 1, the machine further comprises, for example, chains 14 parallel to each other for moving the cores forward up to the channel 24, only one of which is shown.
[0061] The improved rewinding machine for rewinding and forming a paper roll according to the present invention provides for the forming of a finished roll winding the paper supplied by the machine on a core 12.
[0062] Upon completion of the winding process, the machine provides for ripping the paper, ejecting the finished roll and winding the tip of the ripped paper on a new core.
[0063] In particular, according to the invention, the ripping of the paper occurs through the contact of at least one stop element 120', 120", and in particular of one of its peripheral smooth surfaces 133', 133", against portions 16', 16", smooth too, of an upper winding roller 16 on which the paper proceeds.
[0064] Adherence of the paper against the roller 16 is ensured by the fact that the roller 16 is at least of the suctioning type.
[0065] Additionally, according to the invention, it is advantageously possible to provide for portions 116', 116'' provided with friction material arranged at the spaces between a stop element 120', 120" and the subsequent one to ensure further holding of the paper against the roller 16.
[0066] Due to such pairing, provided by the contact between the roller 16 and the related stop group 120 through smooth and not furrowed surfaces as known currently, it is possible to provide for an excellent ripping of the paper within very short periods of time, facilitating in such manner the subsequent winding of the tip of the ripped paper on a related new core 12.
[0067] Furthermore, thus in such manner given the much larger contact surface between the roller 16 and the related paper stop group 120 with respect to the ones provided in the known rewinding machines, the machine advantageously allows ripping also the types of papers with much more trickiness and/or resistance to ripping with respect to the ones used currently.
[0068] Lastly, the production costs of such components are considerably lower with respect to the ones related to the "furrowed" rollers and to the stop groups, "furrowed" too, currently known.
[0069] It has thus been observed that an improved rewinding machine for rewinding and forming a paper roll according to the present invention attains the objectives outlined beforehand.
[0070] The improved rewinding machine for rewinding and forming a paper roll of the present invention thus conceived is susceptible to various modifications and variants, all falling within the same invention concept; furthermore, all the details can be replaced by other technically equivalent elements. In practice, the material used, alongside their dimensions, may vary depending of the technical requirements.
1. Improved rewinding machine for rewinding and forming a paper roll comprising three
rollers (16, 17, 18) with axis parallel to each other and perpendicular to the direction
of forward movement of the paper, wherein the two upper and lower winding rollers
(16, 17) cooperate with a third roller (18), connected by a pair of oscillating arms
(22), adapted to keep a given pressure on a roll, or log, to form a finished roll,
which exits from said machine through an exit opening (30) provided between said lower
winding rollers (17) and said third roller (18), by winding of said paper, which passes
on said upper winding roller (16), around a core (12), an introduction group (13)
of said cores (12) one after the other into a channel (24) provided beneath said upper
roller (16), and a paper stop group (120) which cooperates with at least one first
surface portion (16', 16") of said upper roller (16) on which it operates rotating
around a pin (128) parallel to said roller (16), wherein said stop group (120) comprises
at least one said paper stop element (120', 120") provided with an arm (132', 132")
rotating around said pin (128) and with a free end made up of a smooth surface (133',
133"), and in which said at least one first surface portion (16', 16") of said upper
roller (16) is smooth and provided with a plurality of air suctioning holes (101)
for holding said paper wound on said upper roller (16).
2. Machine according to claim 1 characterised in that said stop group (120) comprises a plurality of said stop elements (120', 120") arranged
successively one after the other and separated from each other by interspaces and
in that said surface of said upper roller (16) comprises at least a second portion (116',
116") provided with friction material at said interspaces.
3. Machine according to claim 2 characterised in that said friction material is tungsten carbide.
4. Machine according to any of the preceding claims characterised in that said at least one first smooth surface portion (16', 16") of said upper roller (16)
on which said stop group (120) operates is made of aluminium.
5. Machine according to claims 1 or 2 or 3 characterised in that said at least one first smooth surface portion (16', 16") of said upper roller (16)
on which said stop group (120) operates is made of iron.
6. Machine according to any of the preceding claims characterised in that said smooth surface (133', 133") of said at least one stop element (120', 120") is
made of friction material.
7. Machine according to the preceding claim characterised in that said smooth surface (133', 133") is made of vulcanised rubber.
8. Machine according to claim 1 characterised in that said introduction group (13) comprises a pusher conveyor (15) upstream of said three
rollers (16, 17, 18) for the introduction of said cores (12) one after the other into
said channel (24) provided beneath said upper roller (16), and a rotating pusher (35)
adapted to move said cores (12) forward into said channel (24).
9. Machine according to claim 1 characterised in that said upper roller (16) comprises a plurality of longitudinal channels (100) arranged
as a circular ring in proximity to the cylindrical surface of said roller (16) arranged
connected to the external through said plurality of holes (101).
10. Machine according to claim 9 characterised in that it comprises at least one pair of circular section-shaped sliding suctioning elements
(102) arranged in axis with respect to said roller (16) fixed and facing the opposite
tips adapted to trigger the air suctioning through the channels (100) comprised between
them.
11. Machine according to claim 1 characterised in that said stop group (120) is arranged upstream of said channel (24).
12. Machine according to claim 1 characterised in that said stop group (120) is arranged inside said channel (24).