CN111836770A

CN111836770A - Overlapping machine with separating jaws adjacent to respective overlapping rollers

Info

Publication number: CN111836770A
Application number: CN201980017784.XA
Authority: CN
Inventors: G·马扎切里尼; A·莫雷利
Original assignee: Fabio Perini SpA
Current assignee: Fabio Perini SpA
Priority date: 2018-02-02
Filing date: 2019-02-01
Publication date: 2020-10-27
Also published as: ES2910364T3; CN208843427U; BR112020015563A2; EP3746386A1; IT201800002342A1; US20210047142A1; CN208843441U; EP3746386B1; EP3746386B8; WO2019149905A1

Abstract

The overlapping machine (1) comprises a first overlapping roller (9) rotating around a first rotation axis (9A), and a second overlapping roller (11) rotating around a second rotation axis (11A) parallel to the first rotation axis (9A), wherein the first overlapping roller (9) and the second overlapping roller (11) form an overlapping nip (13) therebetween. The machine further comprises a first set of separating jaws (21) associated with the first overlapping roller (9) and arranged to pivot reciprocally about a first pivot axis (21A) parallel to the first rotation axis (9A). The reciprocating pivotal movement of the first set of separating pawls (21) is controlled by a first actuating mechanism (25) comprising a first linked track cam (51). The machine (1) also comprises a second set of separating jaws (23) associated with the second overlapping roller (11) and arranged to pivot reciprocally about a second pivot axis (23A) parallel to the second rotation axis (11A). The reciprocating pivotal movement of the second set of separating pawls (23) is controlled by a second actuating mechanism (27) comprising a second desmodromic cam (51).

Description

Overlapping machine with separating jaws adjacent to respective overlapping rollers

Technical Field

The invention relates to a blending machine. More particularly, the present invention relates to an improvement of a reciprocating separation claw incorporated to an overlapping roller for separating a folded sheet therefrom.

Background

The overlap machine is commonly used in industry to manufacture stacks of overlapping sheets. A folding machine is for example used for manufacturing stacks of folded tissue paper napkins or similar tissue products.

Typically, the overlapping machine comprises counter-rotating overlapping rollers arranged adjacent to each other and having parallel axes of rotation, defining an overlapping nip therebetween. The sheets produced by cutting the continuous web are alternately supplied to one and the other of said overlapping rollers. Each sheet is folded along a central fold line to form two sheet portions. The two sheet portions of each sheet are placed between the two sheet portions of a preceding sheet and the two sheet portions of a following sheet, for example to form a stack of overlapping sheets.

To separate each folded sheet from the respective overlapping sheet roll, two sets of reciprocating separation claws are associated with the two overlapping rolls. The separating jaws perform a reciprocating pivoting movement about the respective pivot axis at a very high rate, which corresponds to the productivity of the machine.

In order to achieve higher productivity, it would be beneficial to design a separating pawl that can move at a higher rate.

Disclosure of Invention

According to one aspect, the invention relates to an overlapping machine comprising: a first overlapping roller rotating about a first rotation axis; and a second overlapping roller rotating about a second axis of rotation parallel to the first axis of rotation. The first overlapping roller and the second overlapping roller together form an overlapping nip therebetween. According to embodiments disclosed herein, the blending machine further comprises: a first set of separating jaws associated with the first overlapping roller and arranged to pivot reciprocally about a first pivot axis parallel to the first rotation axis; and a second set of separating jaws associated with the second overlapping roller and arranged to pivot reciprocally about a second pivot axis parallel to the second rotation axis. The reciprocal pivoting movement of the first and second sets of separating jaws is controlled by a first and second actuating mechanism, respectively. Each actuator mechanism includes a respective desmodromic cam (desmodromic cam).

Additional features and embodiments of the inventive blending machine are set forth in the dependent claims and are described in more detail herein with reference to the drawings.

Drawings

A more complete understanding of the disclosed embodiments of the present invention and many of the attendant advantages thereof may be more readily obtained by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

figure 1 shows a schematic front view of a blending machine according to the invention;

FIG. 2 shows an enlarged view of a portion of FIG. 1;

fig. 3 shows a side view according to the line III-III in fig. 2;

FIGS. 4A to 4C show a series of operations in the first embodiment;

FIGS. 5A-5C illustrate a series of operations in the second embodiment;

FIG. 6 shows a view according to line VI-VI of FIG. 2;

fig. 7 shows a cross-sectional view according to line VII-VII of fig. 6;

FIGS. 8A, 8B show views according to line VIII-VIII of FIG. 7; and

fig. 9 shows a stack of overlapping sheets.

Detailed Description

Fig. 1 shows a front view of a blending machine according to the invention. The overlapping machine 1 comprises a first feed path for a first thin continuous web N1 and a second feed path for a second thin continuous web N2. A first rotary cutting roller 3 is arranged along a first path, the first rotary cutting roller 3 being provided with angularly spaced blades 3A. The blade 3A co-acts with a first fixed anvil blade 4. A second rotary cutting roller 5 is arranged along a second path, the second rotary cutting roller 5 being provided with angularly spaced blades 5A. The blade 5A co-acts with a second stationary anvil blade 6. The first cutting roller 3 rotates about a first axis of rotation 3B, while the second cutting roller 5 rotates about a second axis of rotation 5B.

The first cutting roller 3 is further provided with a suction port 3C along its cylindrical surface. The second cutting roller 5 is in turn also provided with suction openings 5C along its cylindrical surface. The

suction openings

3C, 5C are intended to hold the sheet material produced by cutting the continuous first web N1 and second web N2 on the surface of the respective cutting roller 3, 5 and to convey said sheet material from the cutting roller 3, 5 to the overlapping

roller

9, 11.

The overlapping

rollers

9, 11 rotate about respective axes of

rotation

9A, 11A parallel to each other and to the axis of rotation of the cutting rollers 3, 5. The two overlapping

rollers

9, 11 form an overlapping nip 13. Each of the overlapping

rollers

9, 11 is provided with a respective folding member 15, 17. The folding members 15, 17 may provide suction means or mechanical gripping means or both. The overlapping rollers and folding members are known to those skilled in the art and are not described in detail.

Each continuous web N1, N2 is guided around a respective rotary cutting roller 3, 5 and fed between the cutting roller 3, 5 and a fixed anvil blade 4, 6. The cooperation of the rotary blade 3A with the stationary anvil blade 4 cuts the continuous web N1 into individual sheets which are then transferred from the first cutting roller 3 to the first overlap roller 9. Similarly, the continuous web N2 is guided around the second cutting roller 5 and cut into sheets by the cooperation of the rotary blade 5A and the fixed anvil blade 6. The single sheet is then transferred from the second cutting roller 5 to the second overlapping roller 11.

A first set of separating claws 21 is associated with the first overlapping roller 9. The first set of separating fingers 21 is best shown in figures 6 and 7. The first overlapping roller 9 is provided with a plurality of annular grooves 9G. In the example shown in fig. 6, there are seven annular grooves 9G and seven separating claws 21 forming a first group of separating claws. Each of the separation claws 21 cooperates with a corresponding one of the annular grooves 9G provided in the first overlapping roller 9.

A second set of separating claws 23 is associated with the second overlapping roller 11. The second set of separating fingers 21 is best shown in figures 6 and 7. The second overlapping roller 11 is provided with a plurality of annular grooves 11G. In the example shown in fig. 6, there are seven annular grooves 11G and seven separating claws 23 forming a first group of separating claws. Each of the separation claws 23 cooperates with a corresponding one of the annular grooves 11G provided in the second overlapping roller 11.

A different number of separating fingers and recesses may be provided.

The

annular grooves

9G and 11G provide annular spaces that protrude inside the cylindrical surfaces of the first and second overlapping

rollers

9 and 11. As shown in fig. 7, each separation claw 21 may protrude in a corresponding annular groove 9G inside the overlapping roller 9. Similarly, each separation claw 23 may protrude in a corresponding annular groove 11G in the cylindrical surface of the overlapping roller 11.

The first set of separating jaws 21 is controlled by a respective first actuating mechanism 25, which will be described in more detail later. The first actuator mechanism 25 drives the first set of separating claws 21 in a reciprocating pivotal movement about a first pivot axis 21A parallel to the axis of rotation 9A of the first overlapping roller 9. As shown in fig. 7, the pivot axis 21A may be located on or within the cylindrical surface of the first overlapping roller 9. In fig. 7, the two end positions of the reciprocally pivoting first set of separating fingers 21 are shown. In the first position shown in dashed lines, the distal end of the first separating claw 21 (i.e. the free end opposite the pivot axis 23A) is arranged at least partially within the annular groove 9G. In the second position, shown in solid lines, the distal end of the first separating claw 21 is located outside the cylindrical surface of the first overlapping roller 9.

A symmetrical arrangement is provided for the second set of separating claws 23. The second set of separating jaws 23 is controlled by a corresponding second actuating mechanism 27, similar or identical to the first actuating mechanism 25. The second actuator mechanism 27 drives the second set of separating pawls 23 in a reciprocating pivotal motion about a second pivot axis 23A parallel to the rotational axis 11A of the second overlapping roller 11. As shown in FIG. 7, the pivot axis 23A may be located on or within the cylindrical surface of the second cross-over roller 11. In fig. 7, the two end positions of the reciprocally rotating second set of separating fingers 23 are shown. In the first position, shown in solid lines, the distal end of the second separating claw 23 is at least partially arranged within the annular groove 11G. In the second position, shown in broken lines, the distal end of the second separating claw 23 is located outside the cylindrical surface of the second overlapping roller 11.

As shown in fig. 7, the pivoting movement of the first set of separating claws 21 is in anti-phase with respect to the movement of the second set of separating claws 23, so that when the first set of separating claws 21 is inside the annular groove 9G the second set of separating claws 23 is outside the annular groove 11G and vice versa. The separating

fingers

21, 23 separate the folded sheets from the respective overlapping

rollers

9, 11 and place the sheets on a first or second pair of counter combs, described below, to form a stack of overlapping sheets thereon.

In a preferred embodiment, the first and second sets of separating

claws

21, 23 are moved synchronously with the folding members 15, 17, so that when the folding members release the folded sheet S1 or S2, the separating

claws

21 or 23 disengage the folded sheet from the respective overlapping

rollers

9, 11 or assist in disengaging the folded sheet from the respective overlapping

rollers

9, 11. The optimum law of motion of the sets of

separation pawls

21, 23 can be obtained using respective desmodromic cams (to be described later). The desmodromic cams can be assembled in the correct phase with respect to the overlapping

rollers

9, 11.

The operation of the overlapping machine 1 is generally known in the art and does not require a detailed description. The co-action of the two overlapping

rollers

9, 11 and the sets of separating

claws

21, 23 produces a stack of sheets folded onto each other, one of which is schematically shown in fig. 9 and labelled SK. The sheet S1 is conveyed by the first overlapping roller 9, and the sheet S2 is conveyed by the second overlapping roller 11. Each sheet S1 has a central fold line F1 that divides the sheet S1 in half. Each sheet S2 has a central fold line F2 that divides the sheet S2 in half. The sheets S1, S2 are staggered or alternating in the sense that each half of the sheet S1 is disposed between two halves of the sheet S2, and vice versa. Half portions of two continuous sheets S1 are placed between the two half portions of each sheet S2. Similarly, half portions of two continuous sheets S2 are positioned between the two half portions S1 of each sheet S1. In this configuration, the folded sheet includes the trailing end of the preceding sheet and the leading end of the succeeding sheet, thereby forming an overlapped sheet stack SK.

Each first disengaging pawl 21 is pivotally hinged to a respective securing arm 29. The fixing arm 29 is integrally supported by a fixing frame 31, and this fixing frame 31 also supports the first and second overlapping

rollers

9 and 11. Similarly, each second disengaging pawl 23 is pivotally hinged to a respective securing arm 33. The fixing arm 33 is integrally supported by the fixing frame 31.

The fixing

arms

29 and 33 extend from the fixing frame 31 to the front of the respective overlapping

rollers

9, 11 on the side opposite to the sheet arrival in the overlapping nip 13. The fixing

arms

29 and 33 protrude from the fixing frame 31 toward the overlap nip 13. As best shown in fig. 7, in this embodiment, each fixing arm 29 extends beyond the rotation axis 9A of the first overlapping roller 9 towards the overlapping nip 13. Similarly, each fixing arm 33 extends from the fixing frame 31 toward the overlap nip 13 beyond the rotation axis 11A.

As shown in fig. 7, each fixing arm 29 and each fixing arm 33 may have a proximal end constrained to the fixing frame 31 and a distal end extending towards the cylindrical surface of the respective overlapping

rollers

9 and 11. Preferably, as shown in fig. 7, the distal end of each of the fixing

arms

29 and 33 protrudes inside a corresponding one of the first annular groove 9G and the second annular groove 11G, respectively.

The reciprocating pivotal movement of the first set of separating jaws 21 is transmitted from the first actuating mechanism 25 through the respective connecting rod 35. The reciprocating pivoting motion of the second set of separating jaws 23 is transmitted from the second actuating mechanism 27 through respective connecting rods 37.

Reference numeral 35A denotes a hinge point between the connecting rod 35 and the separating claw 21, and reference numeral 37A denotes a hinge point between the connecting rod 37 and the separating claw 23.

The separating

fingers

21, 23 and/or the connecting

rods

35, 37 can be made of a light material (for example aluminium, carbon fibre, plastic or resin or fibre-reinforced resin) to reduce the mass and therefore the inertia thereof.

The first actuating mechanism 25 comprises a first rotation shaft 39 providing a reciprocating rotational movement about an axis 39A, the axis 39A extending parallel to the rotation axis 9A of the first overlapping roller 9 and away from the rotation axis 9A of the first overlapping roller 9, i.e. the rotation shaft 39 is not coaxial with the respective overlapping roller 9. The second actuator mechanism 27 similarly comprises a symmetrical second rotation shaft 41 providing a reciprocating rotational movement about an axis 41A, the axis 41A being parallel to the rotation axis 11A of the second overlapping roller 11 and remote from the rotation axis 11A of the second overlapping roller 11, i.e. the rotation shaft 41 is not coaxial with the respective overlapping roller 11.

As best shown in fig. 7, each connecting rod 35 is drivingly coupled to the first rotary shaft 39 by a respective crank 43; reference numeral 43A denotes a hinge point between the crank 43 and the connecting rod 35. In a symmetrical manner, each connecting rod 37 is drivingly coupled to the second rotation shaft 41 by a respective crank 45; reference numeral 45A denotes a hinge point between the crank 45 and the connecting rod 35. The reciprocating rotational motion of the first rotating shaft 39 and the reciprocating rotational motion of the second rotating shaft 41 are transmitted to the respective first group 21 and second group 23 of separating claws through the cranks 43 and 45 and through the connecting

rods

35 and 37.

Referring again to fig. 7, the distance between the rotational axis 39A (or rotational axis 41A) and the hinge point 43A (or 45A) is labeled as L1. The distance between pivot axis 21A (or 23A) and hinge point 35A (or 37A) is labeled L2. In a preferred embodiment, L1 is larger than L2 so that a small angular movement of the

rotating shafts

39 and 41 is sufficient to cause a suitable oscillation of the separating

jaws

21, 23.

Both ends of each connecting rod may be hinged to the respective disengaging pawl and to the respective crank by means of lubricated bearings to reduce wear and to extend the service life of the bearings.

According to the embodiments disclosed herein, the reciprocating rotational motion of the first and second

rotational shafts

39 and 41 is imparted by respective desmodromic cams. The desmodromic cam of the first actuator mechanism 25 is shown in fig. 8A and 8B. The desmodromic cams of the second actuation mechanism 27 are symmetrical and not shown in the figures. In fig. 8A, 8B, a desmodromic cam that controls the rotational movement of the first rotating shaft 39 is denoted by 51. In this embodiment, the desmodromic cam 51 is a dual body cam having a first cam body 51A and a second cam body 51B. The two

cam bodies

51A, 51B are rigidly constrained to each other and together form a desmodromic cam 51. The first cam body 51A has a first cam profile 53A and the second cam body 51B has a second cam profile 53B. Desmodromic cam 51 cooperates with a rocker arm 57 constrained to first axis of rotation 39. Rocker arm 57 is a double arm having two distal ends, i.e., an L-shaped arm. The two distal ends each support a respective roller, wheel or other contact body which co-acts with one of the cam profiles 53A, 53B. The first and second contacts are indicated at 59A and 59B. The first contact 59A contacts the first cam profile 53A, while the second contact 59B contacts the second cam profile 53B.

Therefore, the continuous rotational motion according to the arrow f51 of the desmodromic cam 51 is converted into the reciprocating rotational motion of the rotary shaft 39 about the axis 39A (arrow f 39). The rotation of the rotating shaft 39 in both directions (clockwise and counterclockwise) is reliably controlled by the two

cam profiles

53A, 53B of the desmodromic cam 51. This enables a very high speed of reciprocating rotary motion and therefore a high productivity of the machine 1.

Different desmodromic cams may be provided, for example cams having channels in which a single contact member is located. The contact member contacts opposing cam profiles formed by opposing sidewalls of the channel.

The second rotation axis 41 can be controlled by a symmetrical mechanism with a desmodromic cam, not shown, which can be designed in the same way as the desmodromic cam shown in fig. 8A and 8B.

Desmodromic cams can be accommodated in respective cassettes 61, 63 (fig. 6). The rotational movement of the desmodromic cam 51 is obtained by the continuous rotational movement of the respective first and second overlapping

rollers

9, 11 as described below. The first gearwheel 71 may be keyed on a first shaft 73 of the first overlapping roller 9. The second gear 75 may be keyed on the second shaft 77 of the second overlapping roller 11. The first and

second gears

71, 75 are in mesh with each other so that the first and

second crossover rollers

9, 11 can rotate in opposite directions (arrows f9, f11 in fig. 6) under the control of a motor as schematically shown by reference numeral 81 in fig. 6. The respective first pinions 83 are in mesh with the first gear 71. The first pinion gear 83 may be keyed to a first camshaft 85, and the desmodromic cam 51 may be keyed to the first camshaft 85 (fig. 8A, 8B). Similarly, the second pinion gear 87 meshes with the second gear 75 and is keyed on a second cam shaft 89, and a desmodromic cam (symmetrical to the cam 51 and not shown) is keyed on the second cam shaft 89 to control the reciprocating pivotal motion of the second rotary shaft 41. As shown in the figures, see for example fig. 6 and 8A, 8B, the first and

second cam shafts

85, 89 are parallel to the associated rotation axes 9A, 11A and rotation axes 73, 77 of the overlapping

rollers

9, 11, but remote from the associated rotation axes 9A, 11A and rotation axes 73, 77 of the overlapping

rollers

9, 11, i.e. not coaxial with the associated rotation axes 9A, 11A and rotation axes 73, 77 of the overlapping

rollers

9, 11, so that the desmodromic cam rotates about an axis that is remote from and remote from (not coaxial with) the rotation axes 9A, 11A of the overlapping

rollers

9, 11.

Thus, the first

gear train connections

71, 83 transfer the rotational movement from the first overlapping roller 9 to the first desmodromic cam 51, while the second

gear train connections

75, 87 transfer the rotational movement from the second overlapping roller 11 to the second desmodromic cam (not shown and symmetrical to the cam 51). In this way, the rotational movement of the desmodromic cam and the reciprocating movement of the rotary shafts 39, 41 (and therefore of the separating pawls 21, 23) are synchronized with the rotational movement of the overlapping

rollers

9, 11.

In other embodiments, a different transmission arrangement may be provided, for example using an endless belt to transmit motion from the

laminating rollers

9, 11 to the desmodromic cam. However, the use of a gear train may be advantageous for better control of the motion.

The use of desmodromic cams to control the oscillating movement of the separating

jaws

21, 23 can be advantageous in at least two respects. Firstly, these cams allow very high frequency reciprocating oscillating movements to be achieved with good motion control. The number of oscillations per minute of the separating pawl may be up to 25 oscillations per second or more. Secondly, the law of motion of the separating claw can be easily modified by replacing the desmodromic cam with another set of desmodromic cams having a different cam profile.

Although according to the embodiment shown in the figures the desmodromic cams 51 are driven in rotation by the same motor 81 that drives the rotation of the overlapping

rollers

9, 11, in other embodiments separate motors may be provided for each desmodromic cam. In other embodiments, a single motor, independent of motor 81, may be provided to drive both desmodromic cams in rotation. If one or two independent motors are used to drive the desmodromic cams, these motors will be electronically controlled to rotate in synchronism with the overlapping

rollers

9, 11. If separate motors are used for the desmodromic cam on one side and for the overlapping rollers on the other side, the phase between the overlapping rollers and the desmodromic cam can be easily adjusted, for example by acting on one of said motors, usually on the motor controlling the rotation of the desmodromic cam.

According to some embodiments, the desmodromic cam profile can be adjusted to impart different movement speeds to the separating

jaws

21, 23 during the moving-away and returning movements, i.e. during the pivoting movement away from the overlapping

rollers

9, 11 and during the pivoting movement towards the overlapping

rollers

9, 11. More specifically, according to some embodiments, the removal movement (i.e. the movement by which the

separation jaws

21, 23 disengage the folded sheets from the respective overlapping rollers 9, 11) may be slower than the return movement. In other embodiments, the opposite may be provided, i.e., the move-away motion may be faster than the return motion. The choice of which movement is faster depends inter alia on the characteristics of the material from which the sheets are made (e.g. tissue), the number of sheets in each stack, the number of plies per sheet, etc. For example, a slower removal movement may be beneficial in order to perform a milder action on the tissue paper to prevent damage to the sheet when it is being released from the overlapping

rollers

9, 11.

To form a stack of overlapped sheets S1, S2 containing a predetermined number of sheets, pairs of counting combs may be provided as will be described in detail hereinafter with particular reference to fig. 1 to 5.

More specifically, with particular reference to fig. 2, the first pair of counting combs 91, 93 is symmetrically arranged in front of the overlapping gripping portions 13 on the side on which the separating

pawls

21, 23 are located. A second pair of counter combs 95, 97 is further symmetrically arranged in front of the overlapping grips 13.

For the sake of clarity, fig. 2 shows two pairs of counting combs 91, 93, 95, 97, while the separating

fingers

21, 23 are omitted. In fig. 7 described in more detail above, the counting combs 91, 93, 95, 97 are omitted to show the structure of the separating

claws

21, 23 in more detail. Fig. 1 shows the separating claw and the counting comb in combination to better show their mutual position.

Each counting comb can be moved along two translation axes X and Y according to a first direction and a second direction. The axis X is perpendicular to the axes of

rotation

9A, 11A of the overlapping

rollers

9, 11 and parallel to a plane containing the axes of

rotation

9A, 11A. The axis Y is orthogonal to the axis X and the rotation axes 9A, 11A. For each counting

comb

91, 93, 95 and 97, the movements according to axes X and Y are controlled independently, since each counting comb has its own drive unit. However, these movements are synchronized with and coordinated with each other in a manner to be described below to form a series of folded stacks of sheets. The drive units of the counting combs 91, 93, 95, 97 are respectively designated 101, 103, 105 and 107. The drive units may be docked to a single control unit so that their movements may be synchronized.

The

drive units

101 and 105 are substantially identical to each other and in turn substantially symmetrical to the

drive units

103, 107. Therefore, the following detailed description applies to all four drive units 101-107. The structure of the drive unit 103-107 will now be described in more detail with reference to fig. 2 and 3.

Each drive unit comprises a first electronically controlled motor 121 supported by a carriage 123. The carriage 123 supports a rotation shaft 125 extending parallel to the rotation axis 9A of the first overlapping roller 9 and the rotation axis 11A of the second overlapping roller 11. Two

gears

127A, 127B are keyed at the ends of the shaft 125. The gear 127B meshes with an output gear 129 of the first motor 121, so that the rotation of the motor 121 is transmitted to the two

gears

127A, 127B.

The

gears

127A, 127B mesh with

respective racks

131A, 131B forming part of the slider 133. The slider 133 includes a side plate 135, and the

racks

131A, 131B are mounted on the side plate 135. The side plates 135 are interconnected by a beam forming part of the respective counting comb and supporting the teeth or tines of the respective counting comb. In fig. 3, the beams are labeled 93B and the tines or teeth are labeled 93A, and they cumulatively form a counting comb 93. As mentioned above, the remaining count combs 91, 95 and 97 are substantially identical or symmetrical to the count comb 93, and therefore they also have beams supporting respective tines that form part of the respective slider 133.

The slides 133 can reciprocate along the translation axis X with respect to the respective carriages 123. The reciprocating movement along the translation axis X is controlled by a first motor 121. For guiding the slide 133 with respect to the corresponding carriage 123, a guide 137 is provided which extends along the translation axis X.

The carriage 123 of each

drive unit

101, 103, 105, 107 is constrained to a flexible annular member 141. In the embodiment shown in the figures, the flexible annular member 141 comprises two toothed belts which are guided around respective upper and

lower pulleys

143, 145. The upper pulley 143 may be idle-mounted on the fixed frame 31. The lower pulley 145 may be keyed to a shaft 147, and the shaft 147 may be driven to rotate back and forth by a second electronically controlled motor 149. Rotation of the second motor 149 drives the carriage 123 along axis Y. The second motor 149 selectively rotates clockwise and counterclockwise to move the carriage 123 up and down along the axis Y.

The above arrangement is common to all drive

units

101, 103, 105, 107. Each drive unit can therefore control the reciprocating movement of the

respective counting comb

91, 93, 95, 97 in two directions parallel to the axis X and to the axis Y. A control unit 151 (fig. 3) may be connected to each of the first and

second motors

121, 149 of each of the counting combs 91, 93, 95, 97 for electronically controlling the motors and thus the movement of the counting combs so as to form a stack SK of folded sheets S1, S2.

By providing each of the four count combs 91, 93, 95, 97 with a drive unit having the same structure, the construction and maintenance of the overlapping machine becomes simpler. All drive units can use the same spare parts. Thus, by default, there may be only one spare drive unit in order to replace any of the four drive units present in the overlapping machine.

The operation of the counting combs 91, 93, 95, 97 can be controlled in different ways. Two different possible operating sequences for the counting comb are shown in fig. 4A, 4B, 4C and 5A, 5B, 5C, respectively, and will be briefly described below. The movement of the counting comb is controlled such that a stack of a predetermined number of overlapping sheets can be produced.

Referring to fig. 4A, 4B, 4C, the two pairs of counting combs 91, 93, 95, 97 are controlled to perform the same operations in an alternating manner (i.e., in a time-shifted manner), i.e., the first pair of counting combs 91, 93 performs the same operations as the second pair of counting combs 95, 97. In fig. 4A, the second pair of counter combs 95, 97 moves downward (direction Y) to remove the first stack SK1 of folded sheets S1, S2 from the overlapping

rollers

9, 11 so that the second stack SK2 of folded sheets S1, S2 can be formed on the first pair of counter combs 91, 93, the first pair of counter combs 91, 93 being located directly below the overlapping nips 9, 11 in front of the overlapping nips 13.

In FIG. 4B, the first pair of counter combs 91, 93 has moved downward a short stroke to allow the second stack SK2 to grow, while the first stack SK1 has been ejected by the second pair of counter combs 95, 97. In this step, the first pair of counter combs 91, 93 supporting stack SK2 being formed moves downwardly at approximately the rate of stack growth, i.e. the height of the stack being formed at its increasing rate.

The second pair of counter combs 95, 97 can discharge the stack SK1 on a conveyor that removes the stack SK1 in a direction orthogonal to the drawing.

After unloading the first stack SK1, the second pair of counting combs 95, 97 has entered the upper position (movement along the respective axis Y). In fig. 4B, the second pair of counter combs 95, 97 is in an idle position. The

combs

95, 97 are spaced apart from each other along the direction of the axis X, so that at this stage they do not interfere with the operation of the overlapping

rollers

9, 11 and the separating jaws 21, 23 (not shown in the sequence of fig. 4A, 4B, 4C), while the overlapping

rollers

9, 11 and the separating

jaws

21, 23 continue to form a second stack SK2 on the first pair of counting combs 91, 93 which progressively move downwards.

Once the desired number of overlapped sheets S1, S2 have been stacked on the first pair of counter combs 91, 93, the second pair of counter combs 95, 97 is moved toward each other in the direction of the axis X, thus separating the stack SK2 from the next input sheet. Simultaneously or immediately thereafter, the counting combs 91, 93 move downwards (along axis Y). In this manner, a third stack SK3 can begin to be formed on the second pair of count combs 95, 97 (as shown in fig. 4C) while the first pair of count combs 91, 93 is moved downward (in the direction of axis Y) to remove the second stack SK 2.

As can be understood from the brief description above with reference to fig. 4A, 4B, 4C, the two pairs of counter combs 91, 93 and 95, 97 perform the same action on a sequentially formed stack of sheets. This may be beneficial for machine programming as the control software becomes simpler.

When a pair of counting combs 91, 93 or a pair of counting combs 95, 97 is in the lower position, the stack supported thereon can be unloaded onto a withdrawal conveyor, such as a withdrawal belt, extending orthogonally to fig. 4A-4C (i.e. parallel to

axes

9A, 11A). In the operating mode of fig. 4A, 4B, 4C, the two pairs of counting combs 91, 93 and 95, 97 are adapted to perform a stroke from an upper position adjacent the overlapping grip 13 (see for example counting combs 95, 97 in fig. 4B) to a lower withdrawal position adjacent the withdrawal strap, see for example counting combs 95, 98 in fig. 4A.

However, the disclosure with reference to fig. 4A, 4B, 4C is not the only possible way to operate the counting comb. In the sequence of fig. 5A, 5B, 5C, each stack SK1, SK2, SK3 is formed in part on the same pair of counting combs 91, 93, and in part on counting combs 95, 97. Only the counting combs 95, 97 are responsible for discharging the formed stack on the removal conveyor. In other words, each stacking cycle is performed partially on the first pair of counting combs 91, 93 and partially on the second pair of counting combs 95, 97.

In the initial step of stack formation, each stack SK1, SK2, SK3 is supported by a counting

comb

91, 93 until the step of transfer of the stack from the first pair of counting combs 91, 93 to the second pair of counting combs 95, 97.

More specifically, when the first pair of counting combs 91, 93 and the second pair of counting combs 95, 97 are at the same level, i.e. at the same height, the counting combs 91, 93 are opened, i.e. spaced apart from each other in the direction of axis X, to discharge the stack being formed on the second pair of counting combs 95, 97 waiting in the rest position. Once the stack being formed has been transferred over the second pair of counter combs 95, 97, the first pair of counter combs 91, 93 moves upwards and returns to a position adjacent the overlapping nips where they will wait for the next stacking cycle to start.

At the same time, the second pair of counter combs 95, 97 moves downward at the stack forming speed, supporting the growing stack. When the first stack SK1 is complete, the counting combs 91, 93 close again (i.e. move along axis X to approach each other), while the second pair of counting combs 95, 97 moves further downwards (axis Y) at a speed greater than the stack growth speed. Once the second pair of counting combs 95, 97 has reached the ejection position, they are spaced apart (movement along axis X) from each other to eject the stack just received from the first pair of counting combs 91, 93.

Once the stack SK1 has been ejected from the second pair of counting combs 95, 97, the second pair of

combs

95, 97 moves upwards (direction of axis Y) and moves again to approach each other (direction of axis X) at a position below the first pair of combs. Thus, the second pair of counter combs 95, 97 is properly positioned to receive the next stack SK2 being formed and temporarily supported by the first pair of counter combs 91, 93.

The position where the stacks being formed are transferred from the first pair of counting combs 91, 93 to the second pair of counting combs 95, 97 can be adjusted as desired and can be selected based on the number of sheets per stack and can be selected such that the dynamics of the counting combs 91, 93 and 95, 97 are optimized, i.e., the dynamic load thereon is minimized.

Stack separation is obtained by inserting counting combs 91, 93 at high speed in the sheet flow. Each counting comb is inserted in phase (moving along axis X) with the sheets and the separating

jaws

21, 23. The first counting comb is inserted when the penultimate sheet is detached from the relative folding roller and marked on the stack by the relative separation claw, the distal end of which is located outside the cylindrical surface of the first overlapping roller 9. When the last sheet is stacked and the associated separation claw is still on the stack, a second counting comb is inserted to complete the stack separation. The second counting comb is a sheet that is out of phase with respect to the first counting comb. During or immediately after the separation phase, the counting combs 91, 93 move downwards to support the advance of the new stack. Thus, according to the operating mode shown in fig. 5A, 5B and 5C, the first pair of counting combs 91, 93 is moved up and down (axis Y) by a short stroke required to allow the stack being formed to grow between the overlapping

rollers

9, 11 and the first pair of

combs

91, 93. In contrast, the second pair of counter combs 95, 97 performs a longer vertical stroke to remove each stack from the pair of overlapping

rollers

9, 11.

In both modes of operation (fig. 4A-4C and 5A-5C), the movement in the X-axis direction of the counting comb can be adjusted in order to separate the completed stack SK from the incoming flow of overlapped sheets delivered by the

counter-overlapping rollers

9, 11. To this end, for example, the approach movements in the direction of the axis X of the counting comb separating the completed stack from the next sheet are out of phase, since the movement of one of the two counting combs starts before the other. In other words, the approach motion of the count comb in the X direction may be asymmetric, i.e., unsynchronized.

Furthermore, the movement of the counting comb is synchronized with the pivoting movement of the separating

jaws

21, 23 in order to separate each completed stack SK from the incoming continuous flow of overlapped sheets from the overlap nip 13.

The following clauses set forth combinations of inventive features that particularly form a part of the present disclosure:

clause 1. an overlapping machine, comprising:

a first overlapping roller rotating about a first rotation axis;

a second overlapping roller rotating about a second rotation axis parallel to the first rotation axis, wherein the first overlapping roller and the second overlapping roller form an overlapping nip therebetween;

a folding member disposed on the first and second overlapping rollers;

a first set of separating jaws associated with the first overlapping roller and arranged to pivot reciprocally about a first pivot axis parallel to the first rotation axis and adjacent to the first overlapping roller;

a second set of separating jaws associated with the second overlapping roller and arranged to pivot reciprocally about a second pivot axis adjacent to the second overlapping roller parallel to the second rotation axis.

Clause 2. the laminating machine according to clause 1, wherein the first pivot axis is arranged on or in the cylindrical surface of the first laminating roller and the second pivot axis is arranged on or in the cylindrical surface of the second laminating roller.

Clause 3. the overlapping machine according to clause 1, wherein each separating finger of the first set of separating fingers is pivotally supported by a respective stationary arm constrained to the stationary frame and drivingly coupled to the first actuating mechanism by a respective first connecting rod; and wherein each separation finger of the second set of separation fingers is pivotally supported by a respective fixed arm constrained to the fixed frame and drivingly coupled to the second actuation mechanism by a respective second connecting rod.

Clause 4. the overlapping machine according to clause 2, wherein each separating finger of the first set of separating fingers is pivotally supported by a respective stationary arm constrained to the stationary frame and is drivingly coupled to the first actuating mechanism by a respective first connecting rod, a first end of the first connecting rod being hinged to the separating finger; and wherein each separation finger of the second set of separation fingers is pivotally supported by a respective fixed arm constrained to the fixed frame and is drivingly coupled to the second actuation mechanism by a respective second connecting rod, a first end of which is hinged to the separation finger.

Clause 5. the overlapping machine according to clause 3, wherein each fixed arm of the first set of separating fingers extends from the fixed frame in front of the first overlapping roller towards the overlapping nip beyond the first axis of rotation; and wherein each fixing arm of the second set of separating fingers extends from the fixing frame in front of the second overlapping roller towards the overlapping nip beyond the second axis of rotation.

Clause 6. the overlapping machine according to clause 4, wherein each fixed arm of the first set of separating fingers extends from the fixed frame in front of the first overlapping roller towards the overlapping nip beyond the first axis of rotation; and wherein each fixing arm of the second set of separating fingers extends from the fixing frame in front of the second overlapping roller towards the overlapping nip beyond the second axis of rotation.

Clause 7. the overlapping machine according to clause 5, wherein each fixed arm of the first set of separating fingers has a proximal end constrained to the fixed frame and a distal end protruding in a respective annular groove of the first overlapping roller; and wherein each fixation arm of the second set of separation fingers has a proximal end constrained to the fixation frame and a distal end protruding in a respective annular groove of the second overlapping roller.

Clause 8. the overlapping machine according to clause 6, wherein each fixed arm of the first set of separating fingers has a proximal end constrained to the fixed frame and a distal end protruding in a respective annular groove of the first overlapping roller; and wherein each fixation arm of the second set of separation fingers has a proximal end constrained to the fixation frame and a distal end protruding in a respective annular groove of the second overlapping roller.

Clause 9. the laminating machine according to any of clauses 3 to 8, wherein the first actuating mechanism comprises a first rotating shaft that performs a reciprocating rotational motion about an axis parallel to the first axis of rotation of the first laminating roller; wherein each first connecting rod is coupled to the first rotation shaft by a respective first crank, the second end of the first connecting rod being hinged to the first crank, such that the reciprocating rotational movement of the first rotation shaft is transmitted to the separating jaws of the first set of separating jaws by the first cranks and the first connecting rods; wherein the second actuating mechanism comprises a second rotary shaft which performs reciprocating rotary motion about an axis parallel to the second axis of rotation of the second overlapping roller; wherein each second connecting rod is coupled to the second rotation shaft by a respective second crank, to which the second end of the second connecting rod is hinged, such that the reciprocating rotational movement of the second rotation shaft is transmitted to the separating jaws of the second set of separating jaws by the second cranks and the second connecting rods.

Clause 10 the overlapping machine of clause 9, wherein the first actuating mechanism comprises a first linked-track cam control mechanism; and wherein the second actuation mechanism comprises a second desmodromic cam control mechanism.

Clause 11 the overlapping machine of clause 10, wherein the first linked-track cam control mechanism includes a first linked-track cam driven to rotate by a first gear train connection between the first overlapping roller and the first camshaft; and wherein the second desmodromic cam control mechanism includes a second desmodromic cam driven to rotate by a second gear train linkage between the second overlapping roller and the second camshaft.

Clause 12 the overlapping machine of clause 11, wherein the first linked orbital cam includes a dual cam profile that coacts with a first rocker arm mounted on the first rotating shaft for common rotation with the first rotating shaft; and wherein the second desmodromic cam comprises a dual cam profile cooperating with a second rocker arm mounted on the second rotation shaft for rotation therewith.

Claims

1. A blending machine (1) comprising:

a first overlapping roller (9) rotating about a first rotation axis (9A);

a second overlapping roller (11) rotating around a second rotation axis (11A) parallel to the first rotation axis (9A), wherein the first overlapping roller (9) and the second overlapping roller (11) form an overlapping nip (13) therebetween;

a first set of separating jaws (21) associated with the first overlapping roller (9) and arranged to pivot reciprocally about a first pivot axis (21A) parallel to the first rotation axis (9A); wherein the reciprocating pivotal movement of the first set of separating jaws (21) is controlled by a first actuating mechanism (25) comprising a first linkage track cam (51);

a second set of separating jaws (23) associated with the second overlapping roller (11) and arranged to pivot reciprocally about a second pivot axis (23A) parallel to the second rotation axis (11A); wherein the reciprocating pivotal movement of the second set of separating fingers (23) is controlled by a second actuating mechanism (27) comprising a second desmodromic cam (51).

2. Overlapping machine (1) according to claim 1, further comprising cutting means (4, 6) able to separate the continuous web (N1; N2) into individual sheets; and wherein the first overlapping roller (9) and the second overlapping roller (11) are capable of overlapping the sheet delivered from the cutting device (4, 6).

3. Overlapping machine (1) according to claim 1 or 2, further comprising a first feed path for a first continuous web (N1) and a second feed path for a second continuous web (N2); wherein the cutting device comprises a cutter capable of dividing the first continuous web (N1) and the second continuous web (N2) into sheets, which are delivered to the first overlapping roller (9) and the second overlapping roller (11).

4. The machine (1) according to claim 1 or 2 or 3, wherein the first linked orbital cam (51) is driven in rotation by a first gear train connection (71, 83) between the first overlapping roller (9) and a first camshaft (85) on which the first linked orbital cam (51) is mounted for co-rotation therewith; and wherein the second desmodromic cam (51) is driven in rotation by a second gear train connection (75, 87) between the second overlapping roller (11) and a second camshaft (89) on which the second desmodromic cam (51) is mounted for common rotation with the second camshaft.

5. Overlapping machine (1) according to claim 1 or 2 or 3, wherein the first overlapping roller (9) and the second overlapping roller (11) are driven in rotation by a first motor (81), and wherein the desmodromic cam (51) of the first actuating mechanism (25) and the desmodromic cam (51) of the second actuating mechanism (27) are driven in rotation by a single additional motor or by two separate additional motors different from the first motor (81) driving in rotation the first overlapping roller (9) and the second overlapping roller (11).

6. Overlapping machine (1) according to any one of the previous claims, wherein each desmodromic cam (51) comprises a first cam profile (53A) and a second cam profile (53B) cooperating with a respective rocker arm (57) configured to transmit a reciprocating pivoting motion to a respective group of separating jaws (21, 23).

7. Overlapping machine (1) according to claim 6, wherein the first cam profile (53A) and the second cam profile (53B) of each desmodromic cam (51) co-act with the first contact body (59A) and the second contact body (59B), respectively.

8. Overlapping machine (1), according to claim 6 or 7, wherein the first cam profile (53A) and the second cam profile (53B) are configured to control the oscillating movement of the respective first and second sets of separating jaws (21, 23) at a higher speed when moving away from the respective overlapping roller (9, 11) and at a lower speed when moving towards the respective overlapping roller (9, 11).

9. The machine (1) according to any one of the preceding claims, wherein each separating jaw of the first set of separating jaws (21) is pivotally supported by a fixed frame (31) and is drivingly coupled to the first actuating mechanism (25) by a respective first connecting rod (35), a first end of which is hinged to the respective separating jaw (21); and wherein each separation jaw of the second set of separation jaws (23) is pivotally supported by the fixed frame (31) and is drivingly coupled to the second actuating mechanism (27) by a respective second connecting rod (37) whose first end is hinged to the respective separation jaw (23).

10. Overlapping machine (1) according to claim 9, wherein the second end of the first connecting rod (35) is hinged to a first rotation shaft (39) of the first actuating mechanism (25), which performs a reciprocating rotary motion about an axis (39A) parallel to the first rotation axis (9A) of the first overlapping roller (9); and a second end of the second connecting rod (37) is hinged to a second rotation shaft (41) of the second actuating mechanism (27), which performs a reciprocating rotational movement about an axis (41A) parallel to the second rotation axis (11A) of the second overlapping roller (11); wherein the first rotary shaft (39) and the second rotary shaft (41) are driven to rotate reciprocally by the respective first and second desmodromic cams (51).

11. Overlapping machine (1) according to claim 9 or 10, wherein the first actuating mechanism (25) comprises a first rotating shaft (39) which performs a reciprocating rotary motion about an axis (39A) parallel to the first rotation axis (9A) of the first overlapping roller (9); wherein each first connecting rod (35) is coupled to the first rotation shaft (39) by a respective first crank (43), to which the second end of the first connecting rod (35) is hinged, such that the reciprocating rotational movement of the first rotation shaft (39) is transmitted to a separating jaw of the first set of separating jaws (21) by the first crank (43) and the first connecting rod (35); wherein the second actuating mechanism (27) comprises a second rotating shaft (41) performing a reciprocating rotational movement about an axis (41A) parallel to the second axis of rotation (11A) of the second overlapping roller (11); wherein each second connecting rod (37) is coupled to the second rotation shaft (41) by a respective second crank (45), to which the second end of the second connecting rod (37) is hinged, so that the reciprocating rotational movement of the second rotation shaft (41) is transmitted to the separating jaws of the second set of separating jaws (23) through the second cranks (45) and the second connecting rods (37); wherein the first rotating shaft (39) is driven by the first linkage control track cam (51) to do reciprocating pivoting motion; and wherein the second rotary shaft (41) is driven to perform reciprocating pivotal motion by a second desmodromic cam (51).

12. Blending machine (1) according to claim 11, wherein the rocker arm (57) of each actuating mechanism (25, 27) is mounted on the respective rotation shaft (39, 41) to rotate jointly with the respective rotation shaft, the rotation of the respective desmodromic cam (51) being converted by said rocker arm (57) into a reciprocating pivoting movement of the rotation shaft (39, 41).

13. The overlapping machine (1) according to claim 11 or 12, wherein the distance (L1) between the axis (39A, 41A) of each first and second rotating shaft (39, 41) and the pivot point between the respective first and second cranks (43, 45) is greater than the distance (L2) between the pivot axis (21A, 23A) of the respective separating claw of the first and second sets of separating claws (21, 23) and the hinge point between said separating claw (21, 23) and the respective first and second connecting rod (35, 37).

14. The machine (1) according to any one or more of the preceding claims, wherein the first pivot axis (21A) is adjacent to the first overlapping roller (9); and the second pivot axis (23A) is adjacent to the second overlapping roller (11).

15. Blending machine (1) according to claim 13, wherein the first pivot axis (21A) is arranged on or in the cylindrical surface of the first blending roller (9) and the second pivot axis (23A) is arranged on or in the cylindrical surface of the second blending roller (11).

16. The machine (1) according to any one or more of the preceding claims, wherein each separating jaw (21) of the first set of separating jaws (21) is pivotally supported on a respective first fixed arm (29) which extends beyond the first rotation axis (9A) towards the overlapping nip (13) in front of the first overlapping roller (9); and wherein each separating claw of the second set of separating claws (23) is pivotally supported on a respective second fixing arm (33) which extends in front of the second overlapping roller (11) towards the overlapping nip beyond the second axis of rotation (11A).

17. The machine (1) according to any one or more of the preceding claims, wherein the first desmodromic cams (51) are mounted on respective first camshafts (85) so as to rotate jointly therewith, and the second desmodromic cams (51) are mounted on respective second camshafts (89) so as to rotate jointly therewith, the first and second camshafts being parallel to and remote from the first axis of rotation (9A) of the first overlapping roller (9) and the second axis of rotation (11A) of the second overlapping roller (11).