AN EXTRACTOR FOR EXTRACTING WINDING MANDRELS FROM ROLLS OF STRIP MATERIAL

Description

Mannucci srl Office Valmet Tissue Converting spa In Lucca AN EXTRACTOR FOR EXTRACTING WINDING MANDRELS FROM ROLLS OF TAPE-SHAPED MATERIAL 5 DESCRIPTION TECHNICAL FIELD

[0001] The present invention relates to devices and methods for extracting a mandrel winding from a roll of ribbon material wrapped around the mandrel. The invention also relates to device components and extraction methods of 10 winding spindles from rolls of web material. EARLY ART

[0002] In many industrial sectors it is expected to wrap a web-like material around a mandrel or winding core. Typically, in the winding industry paper processing, especially tissue paper, is known to wrap a ribbon 15 of paper, consisting of one or more plies, around a winding core or mandrel winding to form a roll. Rolls are normally produced in ra- slow sequence in a rewinder, for example a continuous peripheral rewinder and automatic. Examples of rewinders of this type are described in EP2621844, EP1725485, EP0694020. 20

[0003] Usually, the rolls have a much greater axial length than the finished products, which consist of rolls of shorter axial length, obtained by by transversally cutting the rolls produced by the rewinder.

[0004] In some cases the wrapping takes place around rolls of paper, cardboard or pla- stica, which remain inside the rolls and which are cut together with the rolls. 25

[0005] Systems have already been studied in the past to remove the soul rod or man- winding drum from the finished roll, in order to recycle the mandrels several times in cycles of successive winding of multiple rolls. This saves the need for produce large quantities of winding cores which constitute a cost for Page 1 of 22 Mannucci srl Office the producer of the rolls and a source of pollution. In fact, when the core of the roll the product is cut and remains inside the rolls intended for the final consumer, the latter throws away the winding core once the roll, for example of toilet paper or kitchen paper, it's out. 5

[0006] EP1056667 describes a peripheral rewinding machine that winds rolls of ribbon-like material, typically tissue paper, around removable mandrels. The man- spindles are made in two halves, that is, two half-spindles that are combined together along the winding axis. Downstream of the rewinder there is an extraction device tor, which extracts the two semi-finals from the two ends of the rolls coming out of the rewinder 10 spindles, which are recycled towards the rewinder entrance and coupled together them before being inserted into the rewinder to perform a new winding cycle. chin.

[0007] EP2678257 describes a paper roll production line, in particular tissue paper, which includes a rewinder and a roll accumulator. The rolls are sold 15 are ejected from the rewinder and loaded onto the accumulator, downstream of which they are other transformation machines are present, in particular a cutting machine which Cuts the rolls into smaller rolls, destined for the end consumer. Between the rewinder and the accumulator is provided with an extractor, which extracts half-spindles from the two ends of the rolls being unloaded from the rewinder. 20

[0008] WO2020 / 245319 describes a device for extracting mandrels from rolls of tissue paper through a combined motion of axial translation and rotation of the man- spins around its own axis, to facilitate extraction by reducing friction between the spindle and roll.

[0009] US20240025686 discloses a further winding spindle extractor 25 from tissue paper rolls, which uses an expanding member for holding the mandrel. The expanding gripping member is of the pneumatic or mechanical type.

[0010] DE19957990 describes an expandable gripping member for extracting mandrels wrapping from paper rolls.

[0011] One of the complex aspects in the manufacturing of spindle extractors 30 consists in the need for the extractor to firmly engage the mandrel, or the semi- Page 2 of 22 Mannucci srl Office mandrel, to be able to extract it by overcoming the friction force, without damaging the mandrel without accidentally detaching the extractor. Furthermore, sa- It would be useful to create an extractor that does not require the use of shaped mandrels complex, for example including gripping flanges, since these spindles are co- 5 stosi.

[0012] The purpose of embodiments described herein is to provide a low-power extractor cost-effective, reliable, and can be used with simple tubular mandrels. SUMMARY

[0013] In one aspect, there is described herein an extractor for extracting mandrels or 10 half-mandrels from a roll of wound web material, which extractor com- takes an expandable plug configured to fit inside the chuck of winding and engage the winding mandrel by expansion.

[0014] In embodiments, the expandable plug may comprise a rod and at least an annular body surrounding said rod, the annular body being radially expandable 15 around said rod, to pressurize an internal surface of the man- winding drum.

[0015] In advantageous embodiments, the plug comprises a plurality of annular bodies arranged in sequence along the axial development of the rod. Each body annular is radially expandable around the rod to pressurize the surface 20 internal surface of the winding mandrel.

[0016] In advantageous embodiments, the annular bodies are arranged on the rod free to flow with respect to it.

[0017] In some embodiments, between adjacent annular bodies, ele- rigid annular elements. More specifically, it is possible to foresee a rigid annular element 25 gido interposed between each pair of adjacent annular bodies, i.e. consecutive along the axial development of the rod. The rigid annular element or elements are advantageous. mounted slidingly on the rod, that is, in such a way that they can slide along the length longitudinal of the rod.

[0018] In advantageous embodiments, each annular body is deformable Page 3 of 22 Mannucci srl Office elastically in axial and radial direction, and is configured in such a way that a re- reduction of length in the axial direction causes an expansion in the ra- dial of the annular body.

[0019] In practice, each elastically deformable annular body has a configuration 5 minimum energy ration corresponding to a maximum axial dimension and a minimum radial dimension.

[0020] In embodiments described herein, the rod is housed in a slide guide so as to slide axially in said sliding seat under the control of an expansion actuator, to move between an extraction position and a posi- 10 retraction action with respect to the axial seat.

[0021] For example, the rod may include a radial end stop, such that the retraction of the rod with respect to the sliding seat causes a sliding of the rod inside each annular body and an axial contraction and an expan- radial sion of each annular body. 15

[0022] An extraction device for extracting mandrels is described below. divided into two halves (half-spindles) by rolls of ribbon-like material, typically paper tissue, with a particularly advantageous structure in terms of efficiency and production tivity. It must, however, be understood that the extractor configuration above defi- finished and better described in detail with reference to an illustrated embodiment 20 strata in the drawings, can also be used in spindle extraction devices or semi-spindles different from the one which is the object of the present invention, for example pio not integrated with a roll accumulator. For example, the device can be without accumulator for the rolls and can be configured to extract spindles in a single piece, rather than divided into two half-spindles coupled together. 25

[0023] More generally, the object of this description is also a device for extracting winding mandrels, comprising members for retaining a roll from from which a mandrel is to be extracted, and an extraction assembly comprising at least an extractor as defined above. In advantageous embodiments, the group of extraction is double, and includes two extracting organs aligned along the axis of the ro- 30 tolo, to extract two half-mandrels from two opposite ends of the roll. In this case, each extractor organ includes an extractor as defined above. Page 4 of 22 Mannucci srl Office

[0024] The extraction device may be configured to simultaneously manipulate- a plurality of rolls, in which case the extractor may comprise a plurality of extractors of the type defined above, which act simultaneously on a plurality of spindles inserted into a corresponding plurality of rolls: If the spindles are divided into 5 two half-spindles, two sets of extractors will be provided, one for each end of the rolls. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The invention will be better understood by following the description and the attachments. drawings, which illustrate an exemplary and non-limiting embodiment 10 of the invention. More specifically, in the drawing: Fig.1 shows a front view of a device for extracting mandrels from rolls of web material, including a roll accumulator, according to an embodiment; Fig.2 shows a simplified side view of the device of Fig.1, with 15 parts removed; Fig.3 shows an enlargement of a detail of Fig.2; Fig.4 shows an axonometric view of the device with the accumulator removed; Figs.5 and 6 show enlargements of the two sides of the device in Fig.5; 20 Fig.7 shows an enlarged detail of Fig.5; Fig.8 shows an enlarged detail of Fig.6; Fig.9 shows a further enlargement of Fig.7; Figs.10(A) to 10(J) show an operational sequence of the extraction cycle. tion of the spindles in side view 25 Fig.11(A) to 11(D) show phases of the operating cycle in a front view; Fig.12 shows a phase of discarding a roll from which the spindle; Figs. 13(A) to 13(C) show phases of transfer of semi-spindles extracted from the rolls towards a mandrel conveyor; and 30 Figs. 14 and 15 show the structure and operation of the expander pin. hiss for extracting the spindles. Page 5 of 22 Mannucci srl Office DETAILED DESCRIPTION

[0026] The device for extracting winding mandrels from rolls of na- strip-shaped, for example rolls of tissue paper coming from a rewinder, is indicated overall with 1. The device includes a roll accumulator 3. In the 5 illustrated embodiment, the roll accumulator 3 comprises a structure carrier 4, on which a continuous flexible member 5 is arranged. The flexible member con- tinuo 5 consists of a pair of continuous chains 5A, 5B sent around wheels return teeth 7. In the diagram of the attached figures the roll accumulator 3 is co- consisting of a relatively short closed path of the continuous flexible organ 5, 10 consisting of a single ring sent around two pairs (one for each chain) of idler gears. It must, however, be understood that the roll accumulator 3 can also be much larger and more complex than the one illustrated. For example, The roll accumulator 3 can be configured as described in WO2012104881A1. 15

[0027] As can be seen in particular in Figs.2 and 3, the continuous flexible member 5 includes a straight vertical section, along which other organs of the extraction device, described below.

[0028] Chains 5A, 5B, which constitute the flexible organ contino 5, are connected tied supports for the R rolls. In the illustrated embodiment the supports com- 20 take channels 9 extending longitudinally between the two chains 5A, 5B according to a direction parallel to the axis of the rolls R which are collected on the channels 9. Pre- preferably the channels 9 are arranged at a constant pitch along the development of the organ continuous flexible consisting of the two chains 5A, 5B. Each channel 9 is articulated to the two chains 5A, 5B around a respective longitudinal oscillation axis 9A, 25 parallel to the longitudinal development of the channels 9.

[0029] The channels 9 can be removed from the flexible member 5 to be positioned in different positions, preferably at a constant pace, as still de- written in WO2012104881A1.

[0030] The movement of the continuous chains 5A, 5B, indicated by the arrow f5, along the 30 closed path leads each channel 9 in sequence in front of a ro-loader toli 12, suitable for loading single rolls R onto the channels 9. In the embodiment Page 6 of 22 Mannucci srl Office illustrated, the magazine 12 includes a chute 11 which receives the rolls R from a machine upstream, not shown, such as a rewinder, or a gluing unit tore, which in turn receives the rolls from a rewinder and glues the flap free of the wrapped ribbon material, to prevent it from hindering subsequent operations 5 rations. In the illustrated embodiment, the magazine 12 further comprises a distributor 13, which rotates around an axis 13A parallel to the axes of the rolls R and to the axes 9A of channels 9 according to arrow f13. The distributor 13 is configured for distribute individual R rolls coming from chute 11 onto channels 9.

[0031] The roll accumulator 3 is also equipped with a roll unloading device. 10 toli, not shown, which may be found on the descending branch of chains 5A, 5B. If the ac- roll accumulator 3 is more extensive than the one illustrated schematically, the chains 5A, 5B can define a high number of ascending and descending traits, and the most downstream, with respect to the advancement movement of the rolls R along the accumulator of rolls 3, can be equipped with an unloading device, in a manner known per se. 15

[0032] The device 1 comprises, in addition to the roll accumulator 3, a group of overall extraction indicated with 15.

[0033] The extraction group 15 comprises at least one extraction cradle, on which a roll R is placed from time to time from which the mandrel must be extracted winding. In the illustrated embodiment, the extraction assembly 15 com- 20 takes four extraction cradles indicated with 17, substantially equal to each other, and overlapping. The number of extraction cradles 17 is indicative and may vary, for example also depending on the size of the roll accumulator 3, and more specifically of its height development, or of the machine cycle times that you want to achieve.

[0034] The extraction cradles 17 are aligned with each other in a parallel direction. 25 lela to a section of the closed path defined by the continuous flexible organ 5 (chains 5A, 5B). In the illustrated embodiment, the cradles 17 are advantageously between their overlapping along the vertical development of the first ascending tract of the organ continuous flexible 5. More specifically the extraction cradles 17 are arranged along the ascending section of the continuous flexible organ 5 which develops above the magazine 30 12.

[0035] For the purposes that will be clarified below, the extraction cradles 17 are Page 7 of 22 Mannucci srl Office furniture for selectively assuming: a receiving position, to receive a roll from a respective channel 9 of the accumulator 3; an extraction position. for extract the winding mandrel from the roll R placed on the extraction cradle 17; and an unloading position for unloading the R roll without a winding mandrel 5 from the extraction cradle 17 to a channel 9 of the accumulator 3. Preferably, the roll R is unloaded from the extraction cradle 17 into the channel 9 from which it had been taken. vato.

[0036] In the illustrated embodiment, the extraction cradles 17 are mutually integral and carried by two slides 19, placed at opposite ends of the extraction cradles 10 17. The slides 19 are omitted in Fig.1 and visible in Figs.2 to 9.

[0037] Each slide 19 is equipped with a movement in the horizontal direction, indicated with the double arrow f19x and a movement in the vertical direction, indicated by the double arrow f19y. The f19x movement allows for approaching and retreating of the slides 19 (and therefore of the extraction cradles 17) with respect to the closed path of the 15 chains 5A, 5B and then with respect to the path of the channels 9. The vertical movement according to f19y it is parallel to the direction of movement f9 of the channels 9 along the per- closed course defined by chains 5A, 5B.

[0038] The f19x, f19y movement is obtained by means of a carriage 20, on which are mounted the sleds 19. The carriage 20 comprises two sides 21, between which are placed the cradles of 20 extraction 17 and the slides 19. More specifically, the slides 19 are mounted on the sides 21 via guides 23 (in this case integral with the sides 21) and runners 25 (in this example integral with the sleds 19), see in particular Figs. 7 and 8. The movement according to f19x is obtained by means of a motor 27 (see Fig.8) which drives pinions 29 meshing with racks 31 integral with the slides 19. A torsion bar 30 transmits the motion from one 25 to the other of the sides 21.

[0039] The carriage 20 is in turn mounted on vertical guides 33 integral with the structure 4 and equipped with a movement according to f19y of lifting and lowering along the guides vertical 33 controlled by a motor 34 through toothed belts or other flexible organs hisses 35.. 37 indicates a torsion bar that transfers the motion from the engine 34 30 on the opposite side.

[0040] Each extraction cradle 17 is equipped with a rotational movement around Page 8 of 22 Mannucci srl Office to its own rotation axis 17A, parallel to the axes 9A and the channels 9, as well as to the axes of the R rolls positioned in the extraction cradles 17.

[0041] In the illustrated embodiment, each extraction cradle 17 is provided of an actuator 39 which controls the rotation of the respective cradle 17 around its own 5 rotation axis 17A, via a toothed belt or other continuous flexible member 41, see in particular Figs. 6, 8. For example, the actuator 39 may comprise a motor electric.

[0042] Each extraction cradle 17 is equipped with at least one cooperating pusher 45 with the oscillating channels 9. More specifically, in the example illustrated, each cradle 10 of extraction 17 is equipped with two pushers 45 at the respective longitudinal ends. The pushers 45 are visible in particular in Fig.3 and partially omitted for greater clarity in the remaining figures. The pushers 45 cooperate with cams or stops 47 integral with the channels 9, also visible in particular in Fig.3. As will be clarified in followed with reference to the operating sequence, when the extraction cradle 17 rotates 15 around the axis 17A in a clockwise direction (observing Fig.3), the pushers 45 cooperate with the respective cams 47, causing the respective cam to oscillate in the opposite direction channel 9, which is located in the position adjacent to the extraction cradle 17.

[0043] Each extraction cradle 17 further comprises at least one stop suitable for axially hold the roll R while the winding mandrel is extracted from it 20 ment. Since in the illustrated embodiment the winding mandrel is made in two halves, axially aligned with each other, each extraction cradle 17 It actually includes two retaining stops, designed to hold the two ends axially. stops the roll R during extraction. The two stops are indicated with 49 and are equipped of a movement towards and away from the roll R controlled by an at- 25 actuator, for example a cylinder-piston actuator, indicated by 51. The movement of the bars 49 are indicated by the double arrow f49 (see in particular Figs. 6-9).

[0044] The extraction group 15 comprises an extractor suitable for extracting the mandrels from the rolls R which are located on the extraction cradles 17. In the embodiment illustrated, which is configured to extract split mandrels, the group of 30 extraction, i.e. its extractor, comprises a first extractor organ 63 and a second extractor organ 63, wherein the first extractor organ and the second organ Page 9 of 22 Mannucci srl Office extractors are placed on two opposite sides of the roll accumulator 3 and therefore at opposite longitudinal ends of the extraction cradles 17. Each extractor organ tore 63 is movable on a respective guide 61. In the illustrated example, each guide 61 it's double. 5

[0045] In the embodiment illustrated, each extractor member 63 com- takes, for each extraction cradle 17, a respective gripping element 65, suitable for axially engage a semi-mandrel around which the roll R is wound which is located on the respective extraction cradle 17. In the illustrated embodiment, Thus, four gripping elements 65 are provided on each side of the cradle assembly. 10 extraction 17.

[0046] More specifically, in the embodiment illustrated, the extraction group tion 15 comprises, on each side of the device 1, a guide on which a re- respective extractor organ 63. For simplicity, both extractor organs 63 are shown in Fig.1, while only one of such extractor organs 63 is shown in Figs.4 and 15 9.

[0047] Actuators 67, e.g. electric motors, drive the horizontal movement according to the double arrow f63 of the extractor organs 63, see Fig.1. The movement can be transmitted via a rack and pinion mechanism, for example, as schematically shown in the example illustrated in the attached drawings. 20

[0048] The device 1 further comprises a manipulator for each cradle of extraction 17. The manipulator is designed to grip an impervious winding mandrel extracted from the extractor after being extracted from the roll R which is located on the correspon- extraction cradle tooth 17. The manipulator can be configured to transfer the spindle on a spindle conveyor. 25

[0049] In the embodiment illustrated, since the winding mandrels are divided into two halves, each of which is extracted from one end of the respective roll, the manipulator is double and includes two manipulator organs, one on each side of the device 1.

[0050] More specifically, Fig.4 shows the manipulator organ 71. The manipulator organs 30 symmetrical nipolators on the other side of device 1 are omitted for simplicity of Page 10 of 22 Mannucci srl Office representation. The manipulators 71 are equipped with a horizontal movement, orthogonal to the guides 61 and indicated schematically with the double arrow f71. The mo- movement according to the double arrow f71 allows each semi-spindle to be engaged extracted from the respective roll and transferred to a spindle conveyor, schema- 5 usually indicated with 73 and shown only in Figs.13(A) to 13(C).

[0051] An operating cycle of the device described so far is illustrated in Figs. 10 at 12 and will be described in detail below.

[0052] Fig.10(A) shows the first phase of the extraction cycle. On the accumulation In figure 3 seven R rolls are shown. It should be understood that in general the re- 10 channels 9 can be filled. The extraction cradles 17 are placed at a certain distance (in horizontal direction) from the path of advancement defined by the chains 5A, 5B. On chute 11 there are other R rolls which will be loaded into the subsequent phases. In Fig.10(B) the slides 19 which support the extraction cradles 17 are been brought closer to the ascending straight section of the closed path of the channels 9, 15 defined by the continuous flexible organ 5 (chains 5A, 5B). The reciprocal position in vertical direction of the extraction cradles 17 and the channels 9 is such that the movement approaching movement causes the channels 9 to oscillate around the axes 9A for effect of the interaction between cams or stops 47 and pushers 45. Consequently, the rolls R which are located on the four channels 9 which cooperate with the four cradles of 20 extraction 17 are discharged from the channels 9 and roll into the extraction cradles 17, as shown in Fig.10(C).

[0053] In the next phase, illustrated in Fig. 10(D) the slides 19 move away from the ascending path of the channels 9 and thus allow the channels 9 to return in their rest position, and to the chains 5A, 5B to advance, so that the rolls 25 subsequent ones can advance upwards, without interfering with the extraction cradles 17 and with the rolls placed in them.

[0054] The two half-mandrels that make up each winding mandrel of the rolls R located on the extraction cradles 17 can now be extracted from the extractor organs 63, in the manner described below with reference to Figs. 30 11(A)-11(E).

[0055] After the extraction of the half-spindles from the four rolls R located on the cradles Page 11 of 22 Mannucci srl Office of extraction 17, the latter can translate upwards as shown in Fig.10(E), see arrows in the figure. This movement brings the extraction cradles 17, on which are placed the R rolls from which the winding mandrel has been extracted, in alli- connection with the channels 9, from which these rolls had previously been unloaded 5 (phase of Fig.10(C)). These channels are, in fact, empty, while the channels below are occupied by R rolls, from which the winding mandrels still have to be extracted gimento.

[0056] In the phase of Fig.10(F) the slides 19 are brought closer to the path of the channels 9. The reciprocal position in the vertical direction between channels 9 and extraction cradles 10 17 at this stage is such that the pushers 45 and the cams 47 do not cooperate with each other and the channels 9, constituting the supports of the rolls R of the accumulator 3, remain in position rest period.

[0057] In the next phase of Fig.10(G) the extraction cradles 17 rotate in the direction so as to unload the respective R rolls, without winding mandrel, onto the channels 15 9 from which they had previously been removed. In Fig.10(H) the rolls R without mandrel were transferred from the extraction cradles 17 to the channels 9 and the sleds 19 with the respective extraction cradles 17 released can move away in horizontal direction and then brought back down along the path of advancement of the ca- nalette (see Figs. 10(I) and 10(J) to reposition themselves in the corresponding position 20 tooth in Fig. 10(A). In Fig. 10(J) the rolls R1, R2, R3, R4 are without mandrel winding, while the subsequent rolls R5-R11 still contain the mandrel winding. In the next cycle, the mandrels will be extracted from rolls R5, R6, R7, R8, with a cycle equal to the one previously described.

[0058] The extraction operations of the spindles, or more precisely of the two halves- 25 spindles that form (matched and axially aligned with each other) each spindle of winding, are preferably extracted when the extraction cradles 17 are located compartment in the position of Fig.10(D), with operations illustrated schematically in the se- sequence of Figs. 11(A) to 11(E).

[0059] In Fig.11(A) the rolls R from which the mandrels are to be extracted are loaded 30 on the extraction cradles 17. The two extraction organs 63 are spaced from the extraction cradles extraction 17. The stops 49 are spaced apart enough to allow Page 12 of 22 Mannucci srl Office inserting the R rolls into the extraction cradles 17.

[0060] In the next phase, illustrated in Fig.11(B), the stops 49 are brought closer together at the axial ends of the rolls R in each extraction cradle 17, to retain the roll in a central position during the subsequent extraction phase. In alternating forms 5 implementation methods, the bars 49 can be omitted, if the friction force that must be won to extract the two half-spindles from the roll R is equal or approximately equal for the two half-spindles. In still other embodiments, it can be envisaged that the bat- all 49 are fixed. In this case, even if the friction forces on the two half-spindles are not are balanced, the longitudinal movement of the roll due to the traction exerted 10 tata on the two spindles is limited, and does not affect the correct extraction of the two semi- spindles.

[0061] In Fig.11(C) the two extractor members 63 approach the extraction cradles and the eight gripping elements 65 fit into the two half-spindles of each of the four three rolls R located on the four extraction cradles 17. 15

[0062] In the following Fig.11(D) the two extractor organs 63 have been moved away from the extraction cradles 17 and extracted the two half-mandrels from each roll R M1, M2, which in this phase remain engaged with the gripping elements 65, the structure of which ture and the operation of which in one embodiment will be described in detail further on. During the extraction phase it is possible to foresee the generation of a direct force 20 downwards between each gripping element and its respective half-chuck, for example to facilitate the transfer of a glue, previously applied on the mandrel consisting of the half-mandrels M1, M2 before the start of winding, the half- spindles to the internal coils of ribbon-like material. The downward thrust, which can can be obtained for example by lifting the slides 19, it can also serve to facilitate the in- 25 mutual gluing of the innermost coils of the ribbon-like material that forms each roll.

[0063] Each half-spindle M1, M2 is in this phase facing a respective group of manipulators 71, which engage the semi-spindles M1, M2. In the next stage (Fig.11(E)), the gripping elements 65 are extracted from the man- 30 drini, with an extra-stroke movement of the extracting organs, so that each semi-spindle M1, M2 remains engaged exclusively to the respective organ Page 13 of 22 Mannucci srl Office manipulator 71. At this point, with a movement orthogonal to the plane of Fig. 11(E), the manipulators 71 transfer the half-spindles to the conveyor mandrini 73, which provides for recycling the semi-mandrels towards a rewinding machine. trice, not shown. 5

[0064] As can be seen in Fig.11(E), in this phase the 49 beats from the ends of the R rolls, to allow their subsequent transfer in the channels 9, from which they were taken in the initial phase of the cycle.

[0065] Figs.13(A) to 13(C) show a side view of one of the manipulators. polarizers 71 and the movement with which it engages the semi-spindles M1 extracted from the 10 R rolls, to transfer them with a movement according to the arrow f71 towards the conveyor 73 for the spindles. 74 indicates supports for the half-spindles along a path closed conveyor 73.

[0066] Along the extraction paths of the half-spindles, or in any position suitable, sensors or detectors can be provided to check whether the semi-spindles 15 have been correctly extracted from their respective rolls. This allows you to discard any these rolls R in which one or both half-mandrels M1, M2 remain. In this case any suitable system can be used for this purpose. For example, a vision system, with one or more cameras that detect the presence or absence of semi-spindles in the extracted position (Fig.11(E)). If the detection system 20 should verify the failure to extract one or both half-spindles M1, M2 from one of the rolls R which are located on the extraction cradles 17, these rolls can be expelled from the system and not transferred back into accumulator 3, in order to prevent the half-spindles from entering downstream machines, e.g. cutting machines cutters that cut the rolls into smaller rolls of shorter axial length. 25

[0067] Alternatively to the vision system it is possible to use a first sensor positioned along each of the extraction paths of the semi-spindles, designed to detect the presence or absence of the spindle or semi-spindle in the space in front of each first sensor. For example, the first sensor can be a photocell, or a capacitive sensor. It is possible to place the first sensor in a position adjacent to 30 each extraction cradle 17. In particular it is possible to position each first sensor in an initial section of the extraction path. In this way, by activating in Page 14 of 22 Mannucci srl Office reading the photocell during extraction, in a first time interval, it is possible detect the presence, or passage, of the mandrel and, at the end of the extraction cycle, It is possible to detect the absence of the spindle. This ensures that all the spindle has passed in front of the sensor and therefore the half-spindle is no longer 5 at least partially inserted into the R roll.

[0068] In embodiments, for this purpose, the sensor reading is placed in relation to tion to the position of the respective extractor organ 63 during the extraction cycle. In This way, premature and involuntary disengagement of the gripping element is detected 65 from the respective semi-spindle. The first sensor can be positioned along the 10 extraction path of the spindle or semi-spindle, between the stop 49 and the organ manipulator 71.

[0069] Fig.12 shows an ejection phase of a roll R from which there are no one or both half-spindles have been extracted. In the example, the roll R which is located in the extraction cradle in the highest position it is ejected by a rotation se- 15 condo f17x, in the opposite direction to the rotation direction with which the R rolls are transferred from the extraction cradles 17 to the channels 9. 90 indicates a chute of unloading and 92 indicates a possible conveyor for removing the rejected rolls. The conveyor 92 may be a belt conveyor, equipped with a pa- I slow down to the axis of the rolls R. Since the event of a roll being rejected is very rare, it is 20 can be considered to accumulate the rejected rolls in a static hopper, instead of extracting them with a conveyor.

[0070] In some embodiments, a second sensor may be associated with each extractor organ 63. The second sensor, for example a photocell, is suitable detect that the gripping elements 65 are actually extracted from the half-chuck 25 at the end of the extraction cycle. For this purpose, each second sensor can be placed at a position along each extraction path, so as not to detect the presence of the gripping element 65 once the gripping element 65 has been extracted from the respective half-spindle and that this is supported by the respective manipulator bearer 71. 30

[0071] In other words, the second sensor is designed to detect the presence of the respective gripping element 65 as long as it remains inserted in the respective half-chuck, Page 15 of 22 Mannucci srl Office and is able to detect the absence of the gripping element 65 at the end of the extraction cycle once the gripping element 65 is disengaged from the respective half-spindle. In this This way it is ensured that the disconnection of a gripping element 65 from the respective semi-spindle has been correctly inserted and no problem has occurred which 5 a gripping element 65 remains constrained to its own semi-spindle, dragging it in an incorrect position. The second sensor can be positioned along the per- extraction path, between the manipulator organ 71 and the end-of-travel position of the ele- chin grip 65.

[0072] Additional sensors may be employed along each extraction path. 10 tion to check the correct positioning of each semi-spindle at the end of the extraction cycle.

[0073] A third sensor, such as a photocell, can be used to detect cause an incorrect loading of the R rolls from the channels 9 to the extraction cradles 17. In in this case the sensor is positioned to detect the presence / absence of the R rolls in the 15 space identified between the channels 9 and the extraction cradles 17. In particular, after the receiving phase of a roll R in the extraction cradles 17, the third sensor must detect have an empty space, indicating that none of the R rolls got stuck during the assembly phase load or reception, that is, it remained partly on the channels 9 and partly on the cradles of extraction 17.All the sensors described so far are connected to a control unit, 20 not shown, which can generate alarms and / or stop the loading or unloading phase of the rolls R and / or the extraction phase. In particular, through at least the signal generated by at least one of said first sensors and second sensors, , in case of detection of a spindle or semi-spindle not correctly extracted from a roll R, the control unit can co- send the ejection of the relevant roll R as represented and described in relation 25 at Fig. 12.

[0074] An embodiment of the gripping elements 65 and their operation are described below with reference to Figs. 14 and 15.

[0075] In this embodiment, each gripping element 65 comprises a pin 65.1 comprising a conical distal portion 65.2 integral with a stem or rod 30 65.3. At the opposite end to the conical distal part 65.2, each pin 65.3 each gripping element comprises an actuator 65.4. In the embodiment Page 16 of 22 Mannucci srl Office illustrated, the actuator 65.4 is a cylinder-piston actuator, e.g. of the hydraulic type either electric or preferably pneumatic. In some embodiments, the actuator cylinder-piston 65.4 can be a single-acting cylinder-piston actuator. In other embodiments, the cylinder-piston actuator 65.4 may be double-acting 5 slices.

[0076] The rod or stem 65.3 is guided in a guide 65.6. Between the part of the guide 65.6 facing the distal end of the rod 65.3 and the conical distal part 65.2 are dis- one or more elastically deformable annular bodies 65.7. In the example illustrated they are three elastically deformable annular bodies are foreseen 65.7. Each elastic annular body 10 deformable is mounted idly on the rod 65.3 so that it can slide with respect to to the rod itself. Furthermore, each elastically deformable annular body 65.7 can have a cylindrical or toroidal shape, with an axis coinciding with the axis of the rod 65.3 and a hollow interior, forming the axial passage for the rod 65.3.

[0077] Between adjacent elastically deformable annular bodies 65.7 is interposed 15 a spacer 65.8. Each spacer 65.8 may be approximately cylindrical and has a through hole into which the rod 65.3 is inserted. Each spacer 65.8 is free to slide compared to the 65.3 rod. The 65.8 spacers can be rigid, unlike the bodies elastically deformable rings 65.7. It should be understood that the terms “rigid” and “elastically deformable” are relative terms and refer to the conditions of 20 use of the device described. Therefore, the 65.8 spacers are rigid in the sense that they do not undergo detectable compressive deformations under normal conditions use, while the elastically deformable annular bodies 65.7 compress axially mind and expand radially during use, in the manner and for the purpose set out below described. 25

[0078] The group of spacers 65.8 and elastically deformable annular bodies 65.7 It is located between a radial stop formed by the conical distal part 65.2 and a stop radial formed by the guide 65.6.

[0079] In the rest condition, with the rod 65.3 in the extracted position, as represented shown in Fig.14, the elastically deformable annular bodies 65.7 are in condition 30 undeformed, i.e. in a condition of minimum energy and minimum radial dimension. The outer diameter of the elastically deformable annular bodies 65.7, of the distal part Page 17 of 22 Mannucci srl Office conical 65.2 and spacers 65.8 is such that in this condition the gripping element 65 can be introduced into the semi-spindle M1 (or M2) on which a roll R is wound.

[0080] Once the insertion position has been reached (Fig.14), the rod 65.3 with the conical part terminal 65.2 can be retracted to the position of Fig.15. Since the annular bodies ela- 5 statically deformable 65.7 and the spacers 65.8 are free to slide on the rod 65.3, they remain in a substantially unchanged position with respect to the semi-spindle M1(M2) and the roll. The contraction caused by the retraction of the radial stop formed by the conical part 65.2 causes the axial contraction of the elastic annular bodies deformable 65.7 and their consequent radial expansion. This deforma- 10 tion causes the crushing of the elastically deformable annular bodies 65.7 con- against the internal surface of the semi-spindle. The friction generated between the annular bodies elastically deformable 65.7 and the internal surface of the semi-spindle M1 (or M2) is sufficient to extract the semi-mandrel from the roll R by moving the respective back extractor organ 63. 15

[0081] In essence, therefore, each of the two extractor members 63 comprises an ele- expandable chin which serves to engage the respective semi-mantle by friction from the inside hollow shaft. The use of the elastically deformable annular bodies 65.8 described above allows to avoid the need to use hydraulic or pneumatic expandable elements matic inside the spindles. This makes the impedance system much simpler. 20 reciprocal connection between extractor and spindle, avoids the need for fluid ducts of work and avoids problems arising from possible leaks or seepage.

[0082] Elastically deformable annular bodies can be produced at low cost and can can be easily replaced in case of wear, by simply removing the conical terminal part 65.2, which for this purpose can be screwed onto the rod 65.3, for example. 25

[0083] Furthermore, it avoids engaging the half-spindle from inside and outside as in collet gripping devices, which can damage the semi-chuck or man- drino. Furthermore, by acting only by friction from inside the semi-spindle, it is possible to im- bend mandrels that do not exceed the length of the roll R as they do not oc- runs have an external surface for gripping by a pincer organ. 30

[0084] As far as a device for extracting man- has been described in particular winding spindles composed of two axially coupled half-spindles, it must Page 18 of 22 Mannucci srl Office understand that it is possible to create a completely equivalent machine even in the case in which the winding mandrel is a single tubular element.

[0085] In this case there will be only one extractor organ 63 positioned on a side of the extraction cradle 17, or of each extraction cradle 17. The extraction stroke 5 action carried out by one or more gripping elements 65 will obviously be double what previously described, having to extract the entire mandrel for its entire length ghezza and not just for one half of it. Page 19 of 22

Claims

Claims 1. A stripper for stripping winding mandrels from rolls of wound web material, wherein the stripper comprises an expandable pin configured to be inserted within the winding mandrel and engage the winding mandrel by expansion; and wherein the expandable pin comprises a rod and at least one annular body surrounding said rod, the annular body being radially expandable about said rod, to pressurically engage an internal surface of the winding mandrel.

2. The extractor of claim 1, wherein the at least one annular body comprises a plurality of annular bodies arranged sequentially along the axial extension of the rod, each annular body being radially expandable around the rod to pressurize the internal surface of the winding mandrel.

3. The extractor of claim 2, wherein the annular bodies are arranged on the rod free to slide relative to it.

4. The extractor of claim 3, comprising, between adjacent annular bodies, a rigid annular element, slidably mounted on the rod.

5. The extractor of any preceding claim, wherein each annular body is elastically deformable in the axial and radial directions, a reduction in length in the axial direction causing an expansion in the radial direction of the annular body.

6. The extractor of claim 5, wherein each annular body has a minimum energy configuration corresponding to a maximum axial dimension and a minimum radial dimension.

7. The extractor of any of the preceding claims, wherein Page 20 of 22 Ufficio Mannucci srl the rod is housed in a slide guide so as to slide axially in said slide guide under the command of an expansion actuator, to move between an extraction position and a retraction position relative to the slide guide. 5 8. The extractor of claim 7, wherein said rod comprises a radial end stop, such that the retraction of the rod with respect to the sliding guide causes a sliding of the rod inside each annular body and an axial contraction and a radial expansion of each annular body.

9. A device for extracting winding mandrels from rolls of wound web material; wherein the device comprises members for retaining a roll from which a mandrel is to be extracted, and an extraction assembly comprising at least one extractor according to one or more of the preceding claims.

10. The device of claim 9, comprising a plurality of extractors according to one or more of the preceding claims, configured to engage 15 and simultaneously extract a plurality of mandrels from a plurality of rolls.