A GRIPPER ELEMENT COMPRISING A SENSOR, FOR EXTRACTING WINDING MANDRONS FROM A ROLL, AND EXTRACTION DEVICE COMPRISING SAID GRIPPER ELEMENT

Description

Mannucci srl Office Valmet Tissue Converting SpA Lucca A GRIP ELEMENT COMPRISING A SENSOR, FOR EXTRACTING ONE ROLL WINDING MANDRELS, AND DEVICE 5 EXTRACTION INCLUDING SAID GRIP ELEMENT 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. 10 The invention also relates to device components and extraction methods of winding mandrels 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 15 paper processing, especially tissue paper, is known to wrap a tape 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, 20 EP1725485, EP0694020.

[0003] Usually, rolls have a much greater axial length than 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- 25 stica, which remain inside the rolls and which are cut together with the rolls.

[0005] Systems for removing the rod, core or man- have already been studied in the past. 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 Page 1 of 29 Mannucci srl Office produce large quantities of winding cores which constitute a cost for 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 5 toilet paper or kitchen paper, it's out.

[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 10 tore, which extracts the two semi-finals from the two ends of the rolls coming out of the rewinder 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. This known machine has some limitations. First, the device extractor to extract the half-spindles is placed along the transformation line of the 15 paper and constitutes an additional station which increases the overall size of the line. Furthermore, the extractor slows down the rewinder's production cycle.

[0007] EP2678257 describes a paper roll production line, in particular tissue paper, which includes a rewinder and a roll accumulator. The rolls are sold are expelled from the rewinder and loaded onto the accumulator, downstream of which they are 20 other processing 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. The extractor has a high development along the converting line, and takes up a lot of space between the rewinder and the accumulator. 25 mulator. This space is necessary because the extractor will gradually extract the spindles from the rolls, as they advance along their feed path. The extraction is obtained by combining an advancement motion of the rolls along the line and from an extraction motion according to a diagonal direction of a series of grippers that engage multiple half-mandrels of multiple rolls at the same time. This 30 extraction device is fast, but requires a lot of space and increases considerably- the length of the transformation line and its complexity. The overall dimensions lateral ones also reduce accessibility to the machines downstream of the rewinder and make maintenance difficult. Page 2 of 29 Mannucci srl Office

[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. The device is very bulky and constitutes a long additional element 5 the transformation line, which considerably increases its size. This di- The device also has a very low productivity, as it can extract only one man- one at a time.

[0009] US20240025686 discloses a further winding spindle extractor from tissue paper rolls, which uses an expanding member to grip the mandrel. 10 The expanding gripping device is of the pneumatic or mechanical type. This device is also sitivo is bulky and significantly increases the size of the line.

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

[0011] EP2771320 describes methods and devices for producing rolls of na- 15 coreless winding strip, in which a mandrel is used to wind manage the rolls and then extract them from the rolls to obtain rolls without a winding core. mandrels are tubular and made of plastic material with characteristics such as to pro- to call for a reduction in the diameter of the tubular mandrel when placed under traction during during the extraction phase from the roll. This known device requires extraction means 20 very complex tion.

[0012] One of the drawbacks of the known devices is the high in- encumbrance that these entail within the transformation line. Another in- The disadvantage of some of these devices is their low productivity.

[0013] The purpose of embodiments described herein is to alleviate one or more of the 25 Drawbacks of Prior Art Extraction Devices and Methods.

[0014] The management of the spindle extraction phase presents multiple aspects critical. For example, when the spindle to be extracted is made up of two portions, i.e. two half-mandrels, the extraction of the two half-mandrels from opposite ends of the roll It can be difficult due to the formation of a depression inside the 30 spindle itself, which opposes the extraction of the half-spindles. Page 3 of 29 Mannucci srl Office SUMMARY

[0015] In one aspect, a gripping element for extracting man- winding drums from rolls of wound web material, in which the winding element socket comprises an engagement member configured to engage a mandrel 5 winding; and a sensor, movable with the gripping element and configured to detect the presence of a winding mandrel engaged with the radially expanded pin hissing.

[0016] With this configuration it is possible to detect any malfunctions of a mandrel extraction device comprising a gripping element equipped 10 of sensor, without the need to place external sensors in various positions along the extraction trajectory. The sensor can be used in devices configured with a single gripping element or with two opposing gripping elements to engage from opposite sides of the same roll two semi-mandrels coupled together which form the winding mandrel. 15

[0017] The engagement organ can be configured in various ways. For example the ele- socket chin can be configured as a radially expandable plug suitable for be inserted into the winding mandrel, which can be of tubular structure. In thus the radially expanding pin engages the mandrel on the cylindrical surface internal structure of the tubular structure of the mandrel. This configuration will be de- 20 written in detail with reference to the embodiments illustrated in the drawings al- linked and is particularly advantageous for various reasons which will be clear to the industry experts from the description below.

[0018] In other embodiments, the engagement member may be configured differently and can for example act radially from the outside of the spindle or can 25 include external organs that act radially on the external cylindrical surface of the spindle and one or more internal contrast organs that act on the surface ci- internal cylindrical.

[0019] Furthermore, the gripping element can be single, to extract a mandrel mono-block from a roll. In other embodiments it can be foreseen that the 30 gripping elements are two substantially coaxial and opposite, to engage and extract two half-mandrels which, coupled together, form a mandrel Page 4 of 29 Mannucci srl Office winding.

[0020] In the following description of some embodiments the mandrel is divided into two half-spindles and a double extraction device is provided and symmetrical, with two extractors, each equipped with an extraction element, the two 5 extraction elements being equipped with opposing insertion and insertion movements extraction of two half-spindles.

[0021] The sensor associated with the gripper element can be useful to detect whether a for example a spindle or semi-spindle has not been correctly engaged and therefore It is not extracted from the roll. The same sensor can also be used advantageously. 10 to check that, after extraction from the roll, the mandrel or semi-mandrel be properly removed from the socket for reuse.

[0022] In another aspect, a device for extracting man- winding drums from rolls of wound web material, which device comprises members for holding a roll wound around a winding mandrel 15 chin and from which the winding mandrel must be extracted; and a group of extraction comprising at least one gripping element of the type defined above.

[0023] Further features and embodiments of the gripping element and the spindle extraction device which includes it are described below with reference to the drawings and the attached claims. 20 BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The invention will be better understood by following the description and the attachments. drawings, which illustrate exemplary and non-limiting embodiments of the in- invention. More specifically, the drawing shows: Fig.1 shows a front view of a device for extracting mandrels from rolls 25 of ribbon material, including a roll accumulator, according to a shape of realization; Fig.2 shows a simplified side view of the device of Fig.1, with parts removed; Fig.3 shows an enlargement of a detail of Fig.2; 30 Fig.4 shows an axonometric view of the device with the accumulator Page 5 of 29 Mannucci srl Office removed; Figs.5 and 6 show enlargements of the two sides of the device in Fig.5; Fig.7 shows an enlarged detail of Fig.5; Fig.8 shows an enlarged detail of Fig.6; 5 Fig.9 shows a further enlargement of Fig.7; Figs.10(A) to 10(J) show an operational sequence of the extraction cycle side view of spindles 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 man- 10 drino; Figs. 13(A) to 13(C) show transfer phases of extracted half-spindles from rolls to a spindle conveyor; Figs. 14 and 15 show the structure and operation of the expandable plug for the extraction of the spindles in two different operating positions; 15 Fig.16 shows an enlargement of the expandable plug; the Fig.17 shows a section of an expandable plug in a further form of realization; Fig.18 shows an axonometric view of a plug expandable into a further one embodiment; 20 Fig.19 shows a schematic front view along the line XIX-XIX of Fig.20 of a further embodiment of a device for extracting mandrels; And Fig.20 shows a side view according to XX-XX of Fig.19. DETAILED DESCRIPTION 25

[0025] Figs. 1 to 13 show various views of a roll handling device and the extraction of the mandrels in one embodiment. Innovative features described here can be incorporated into devices of even substantially different shapes different from that represented in these figures, as will be clarified in the se- below with reference to a different form of embodiment. In this first form of 30 realization, in particular, the device for extracting the winding mandrels is combined with a roll accumulator, to obtain some advantages that will result clear to industry experts from the following description. However, features in- innovations of the extractor described in combination with the device of Figs.1 to 13 Page 6 of 29 Mannucci srl Office can also be used in roll management and extraction devices spindles that cannot be combined with an accumulator, for example.

[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 5 in total with 1. In this embodiment, the device comprises a roll accumulator 3. The roll accumulator 3 may comprise 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- 10 consisting of a relatively short closed path of the continuous flexible organ 5, 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 15 WO2012104881A1.

[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 20 tied supports for the R rolls. In the illustrated embodiment the supports com- 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 25 to the two chains 5A, 5B around a respective longitudinal oscillation axis 9A, 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. 30

[0030] The movement of the continuous chains 5A, 5B, indicated by the arrow f5, along the closed path leads each channel 9 in sequence in front of a loader of Page 7 of 29 Mannucci srl Office rolls 12, suitable for loading single rolls R onto channels 9. In the embodiment 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 5 free of the wrapped ribbon material, to prevent it from hindering subsequent operations 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. 10

[0031] The roll accumulator 3 is also equipped with a roll unloading device. 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 15 rolls 3, can be equipped with a discharge device, in a manner known in itself.

[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 20 winding. In the illustrated embodiment, the extraction assembly 15 com- takes four extraction cradles indicated with 17, which are 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. 25

[0034] The extraction cradles 17 are aligned with each other in a parallel direction. 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 30 ascending section of the continuous flexible organ 5 which develops above the magazine 12. Page 8 of 29 Mannucci srl Office

[0035] For the purposes that will be clarified below, the extraction cradles 17 are 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 5 an unloading position to unload the roll R without winding mandrel 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 10 integral and carried by two sleds 19, placed at opposite ends of the extraction cradles 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 15 of the slides 19 (and therefore of the extraction cradles 17) with respect to the closed path of the chains 5A, 5B and therefore 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 20 the sleds 19. The carriage 20 comprises two sides 21, between which are placed the cradles of 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 25 racks 31 integral with the slides 19. A torsion bar 30 transmits the motion from one on the other side 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 30 hisses 35. 37 indicates a torsion bar that transfers motion from the engine 34 on the opposite side. Page 9 of 29 Mannucci srl Office

[0040] Each extraction cradle 17 is equipped with a rotational movement around 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 5 of an actuator 39 which controls the rotation of the respective cradle 17 around its own 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 10 with the oscillating channels 9. More specifically, in the example illustrated, each cradle extraction 17 is equipped with two pushers 45 at the respective longitudinal ends. 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 15 followed with reference to the operating sequence, when the extraction cradle 17 rotates 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 20 axially hold the roll R while the winding mandrel is extracted from it 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 25 of a movement towards and away from the roll R controlled by an at- actuator, such as 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 30 illustrated, which is configured to extract split mandrels, the group of extraction, i.e. its extractor, comprises a first extractor member 63 and a Page 10 of 29 Mannucci srl Office second extractor organ 63, wherein the first extractor organ and the second organ 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 5 is double.

[0045] In the illustrated embodiment, 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, 10 therefore, four gripping elements 65 are provided on each side of the cradle assembly of 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 15 shown in Fig.1, while only one of such extractor organs 63 is shown in Figs.4 and 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, 20 as schematically shown in the example illustrated in the attached drawings.

[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 25 spindle on a spindle conveyor.

[0049] In the illustrated embodiment, 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. 30

[0050] More specifically, in Fig.4 the manipulator organ 71 is shown. The organs Page 11 of 29 Mannucci srl Office symmetric manipulators on the other side of device 1 are omitted for simplicity of 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 5 extracted from the respective roll and transferred to a spindle conveyor, schema- 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 10 tore 3 are shown seven R rolls. It must be understood that in general also the re- The channels 9 can be full. 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 15 state approached to the ascending straight section of the closed path of the channels 9, 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 20 rolls R which are located on the four channels 9 which cooperate with the four cradles of 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 25 in their rest position, and to the chains 5A, 5B to advance, so that the rolls 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 30 from the extractor organs 63, in the manner described below with reference to Figs. 11(A)-11(E). Page 12 of 29 Mannucci srl Office

[0055] After the extraction of the half-spindles from the four rolls R located on the cradles 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- 5 connection with the channels 9, from which these rolls had previously been unloaded (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 10 read 9. The reciprocal position in the vertical direction between channels 9 and extraction cradles 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 15 such as to unload the respective R rolls, without winding mandrel, onto the channels 9 from which they had previously been removed. In Fig.10(H) the R rolls 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- 20 nalette (see Figs. 10(I) and 10(J) to reposition itself in the corresponding trim 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. 25

[0058] The extraction operations of the spindles, or more precisely of the two semi- 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). 30

[0059] In Fig.11(A) the rolls R from which the mandrels are to be extracted are loaded on the extraction cradles 17. The two extraction organs 63 are spaced from the extraction cradles Page 13 of 29 Mannucci srl Office extraction 17. The stops 49 are spaced apart enough to allow the in- Insertion of 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 5 roll in central position during the subsequent extraction phase. In alternating forms of realization, 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 10 are balanced, the longitudinal movement of the roll due to the traction exerted The amount of friction on the two spindles is limited and does not affect the correct extraction of the two halves. 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 15 three rolls R located on the four extraction cradles 17.

[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 20 further on. During the extraction phase it is possible to foresee the generation of a direct force 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 25 can be obtained for example by lifting the slides 19, it can also serve to facilitate the in- 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. 30 In the next phase (Fig.11(E)), the gripping elements 65 are extracted from the man- drini, with an extra-stroke movement of the extractor organs, so that each Page 14 of 29 Mannucci srl Office semi-spindle M1, M2 remains engaged exclusively with the respective mani- polarizer 71. At this point, with a movement orthogonal to the plane of Fig. 11(E), the manipulators 71 transfer the half-spindles to the spindle conveyor 73, which recycles the half-mandrels towards a rewinding machine, not 5 shown.

[0064] As can be seen in Fig.11(E), in this phase it is also possible to move 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. 10 polarizers 71 and the movement with which it engages the semi-spindles M1 extracted from the 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] Fig.12 shows an ejection phase of a roll R from which there are no 15 states extracted one or both half-spindles. In the example, the R roll which is located in the extraction cradle in the highest position it is ejected by a rotation se- second 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. 20 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 you can imagine accumulating the rejected rolls in a static hopper, instead of extracting them with a conveyor.

[0067] An embodiment of the gripping elements 65 and their operation 25 are described below with reference to Figs. 14, 15 and 16.

[0068] In this embodiment, each gripping element 65 of each member extractor 63 includes a radially expandable pin 65.1 which includes a conical distal part 65.2 integral with a stem or rod 65.3. At the opposite end re- with respect to the conical distal part 65.2, each pin 65.3 each gripping element 30 includes an actuator 65.4. In the illustrated embodiment, the actuator 65.4 is a cylinder-piston actuator, for example hydraulic or electric type or preferably Page 15 of 29 Mannucci srl Office pneumatic. In some embodiments, the cylinder-piston actuator 65.4 may be be a single-acting cylinder-piston actuator. In other embodiments, the 65.4 cylinder-piston actuator can be double-acting.

[0069] The rod or stem 65.3 is guided in a guide 65.6. Between the part of the guide 65.6 5 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 deformable is mounted on the rod 65.3 so that it can slide with respect to to the rod itself. The elastically deformable annular body furthest from the end 10 distal part of the rod is only partially free to slide relative to the rod itself due to a 65.9 joke in solidarity with the 65.6 guide.

[0070] Furthermore, each elastically deformable annular body 65.7 may 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. 15

[0071] Between adjacent elastically deformable annular bodies 65.7 is interposed 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 20 “elastically deformable” are relative terms and refer to the conditions of 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 25 described.

[0072] 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 the radial stop 65.9 formed by guide 65.6.

[0073] In the rest condition, with the rod 65.3 in the extracted position, as represented 30 shown in Fig.14, the elastically deformable annular bodies 65.7 are in condition undeformed, i.e. in a condition of minimum energy and minimum radial dimension. Page 16 of 29 Mannucci srl Office The outer diameter of the elastically deformable annular bodies 65.7, of the distal part 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.

[0074] Once the insertion position has been reached (Fig.14), the rod 65.3 with the conical part 5 terminal 65.2 can be retracted to the position of Fig.15. Since the annular bodies ela- 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 10 deformable 65.7 and their consequent radial expansion. This deforma- action 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 15 extractor organ 63.

[0075] 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 20 matic inside the spindles. This makes the impedance system much simpler. reciprocal connection between extractor and spindle, avoids the need for fluid ducts of work and avoids problems arising from possible leaks or seepage.

[0076] Elastically deformable annular bodies can be produced at low cost and can can be easily replaced in case of wear, by simply removing the 25 conical terminal part 65.2, which for this purpose can be screwed onto the rod 65.3 for example.

[0077] 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- 30 runs have an external surface for gripping by a pincer member.

[0078] In advantageous embodiments, to facilitate the extraction of the seeds- Page 17 of 29 Mannucci srl Office spindles M1, M2 via the two opposing radially expanding pins 65.1 of the 65 gripping elements, avoiding a reduction in pressure inside the axial hole of the roll R, in embodiments described herein, each radially expanded pin sibile 65.1 includes an internal duct 65.10 to supply air inside the 5 roll R and more specifically inside the axial hole of the roll R. Each duct interior 65.10 of each radially expandable pin 65.1 further comprises al- minus an air outlet port marked 65.11, located at the distal end of the radially expandable pin 65.1, or in the vicinity of said distal end, for- mata on the distal conical tip 65.2. In the illustrated embodiment, they are pre- 10 views two sets of lights 65.11 configured in the form of two circular sets of inclined holes with respect to the axis of the radially expandable pin 65.1.

[0079] In some embodiments the internal conduit 65.10 is in communication of fluid directly with the external environment, for example it has a pros- end similar, i.e. opposite the distal end 65.12 of the radially expandable pin, 15 open to the external environment. In this way, when the radially expanded pins whistles 65.1 are inserted into the ends of the roll R and engage with the annular bodies elastically deformable 65.7 the internal surface of the two half-spindles (see Fig. 15), when the gripping elements 65 are moved away from each other to extract the semi-spindles M1, M2, inside the central hole of the roll R a 20 reduction in pressure compared to ambient pressure, as air is drawn in from the environment inside the volume formed by the hole in which the spindle is housed M1, M2, through the internal duct 65.10 and the lights 65.11.

[0080] In some embodiments it may also be provided, in order to facilitate further extraction of the semi-spindles M1, M2, to blow inside the ro- 25 tolo R pressurized air. In this case the internal duct 65.10 can be connected with an external tube 65.13, for example a flexible hose, which takes air from a ventilator bearer or from a compressor schematically indicated with 66, or in general from a network of compressed air that can be foreseen in the plant where the line is installed of production of R rolls. A valve 68 on the tube 65.13 can control in a manner 30 selectively supplies pressurized air into the internal duct 65.10. This can for example, allow pressurized air to be introduced only when the radial pins expandable 65.1 have been expanded and have formed a tight seal on the surface internal of the respective half-spindles M1, M2. Page 18 of 29 Mannucci srl Office

[0081] The embodiment of the radially expandable pins 65.1 illustrated in Figs. 14, 15 and 16 is particularly advantageous because the expansion mechanism The system is mechanical and does not require the use of expandable sealing elements. However, the possibility of making radially expandable pins 65.1 is not excluded. 5 with a different configuration, for example with pneumatic expandable bodies. An example of the embodiment of a radially expandable plug 65.1 with a body pneumatically expandable is illustrated schematically in Fig.17. Equal numbers indicate parts equal or equivalent to those described with reference to Figs. 14 to 16, which will not be described again. 10

[0082] Instead of one or more mechanically expandable bodies, such as the bodies 65.7 illustrated layers in Figs. 14 to 16, the embodiment of Fig. 17 comprises one or more pneumatically expandable bodies. In the schematic embodiment of Fig.17 a single pneumatically expandable body is provided, indicated by 65.21. The body pneumatically expandable 65.21 is preferably an annular body. In other forms 15 of construction, to ensure greater grip by friction between the radially pin expandable 65.1 and the semi-spindle M1, M2, two or more bodies can be provided pneumatically expandable 65.21, arranged aligned along the axial development of the radially expandable plug 65.1.

[0083] The expansion of the pneumatically expandable body(s) 65.21 can be 20 obtained by compressed air fed along the same internal duct 65.10. This can be achieved, for example, by providing 65.11 lights with a very small cross-section, so as to generate a high localized pressure drop at the lights themselves. In this way, with a single burst of compressed air, it is possible to obtain a internal pressure in the duct 65.10 sufficient to expand the pneumatic expandable body or bodies 25 matically 65.21, and a modest flow of air towards the inside of the roll R, sufficient to avoid the formation of a depression which can hinder the extraction of the seeds spindles M1, M2. A solution of this type is schematically represented in Fig. 17, where the pneumatically expandable bodies 65.21 are in fluid connection with the internal duct 65.10 via one or more radial holes 65.25. 30

[0084] In other embodiments, within each pin radially expandable 65.1 two internal ducts can be foreseen: a first in- internal to supply air (possibly at ambient pressure or slightly above Page 19 of 29 Mannucci srl Office pressure) towards the 65.11 ports; and a second internal duct to supply compressed air press in pneumatically expanding bodies 65.21.

[0085] Regardless of how the radially expanding pins are configured 65.1, the internal duct(s) 65.10 allow to reduce or cancel the reduction effect 5 of the pressure inside the axial cavity of the roll R during the movement of extraction of the semi-spindles.

[0086] It is thus possible to ensure effective adhesion of the pins radially expandable 65.1 on the internal surface of the respective half-mandrels along the entire development annular shape of the expanding bodies 65.21 or 65.7, without interruptions of the surface of 10 contact, while avoiding resistance to extraction due to depressurization tion of the internal axial cavity of the rolls.

[0087] To further increase the efficiency and correct operation of the extractors tors 63 and related gripping elements 65, to each radially expandable pin 65.2 a sensor can be associated to verify that the radially expandable plug 15 either in contact with the spindle or semi-spindle during the extraction phase, so as to generate an alarm if (for any reason) one or both half-spindles do- were to disengage from the radially expandable pin during extraction or if one or both half-spindles should remain constrained to the respective pin dially expandable once the extraction of the mandrel from the roll R is completed. 20

[0088] Fig.18 shows an axonometric view of a similar gripping element 65 to the gripping element 65 of Figs. 14, 15, 16, with a sensor 70. In the form of embodiment illustrated in Fig.18, the sensor 70 is integral with the guide 65.6 and therefore moves with it, participating in the extraction motion with which the gripping element is equipped 65. 25

[0089] Sensor 70 is configured to detect the presence of a winding mandrel device engaged with radially expandable pin 65.2. In the embodiment illustrated here the winding mandrel is configured in the form of two semi- spindles M1, M2, therefore two opposing extractors are provided, each equipped of one or more gripping elements of as many half-spindles. Therefore, in this example 30 embodiment, each sensor 70 is configured to detect the presence of a semi- mandrel. If, on the other hand, the winding mandrel is made of a single piece, Page 20 of 29 Mannucci srl Office only one extractor will be provided with at least one gripping element on one side of the device, to engage the winding mandrel at only one of the two ends of the R roll.

[0090] The winding spindle presence detection sensor functions 5 works equally in both cases. In one case, two sensors will be provided, one for each of the two opposing gripping elements, in the other case a single sensor for the single gripping element.

[0091] The sensor 70 may be for example a capacitive sensor, or a sensor optical. In the embodiment schematically illustrated in Fig.18 the sensor 70 10 may be an optical sensor that projects an optical beam F onto a portion of the plug radially expandable 65. The sensor 70 is able to detect whether on the portion on where the optical beam F strikes there is a spindle or semi-spindle M1-M2 based on to the characteristics of the optical radiation reflected or backscattered by the surface on which it is affects the optical beam F. The optical type sensor 70 can be a laser sensor suitable for 15 project at least one laser beam, or ray, in the direction of the spindle, or semi-man- drino, in order to measure the distance and determine whether or not it is present based on it of the spindle, or semi-spindle, itself.

[0092] Other embodiments of the sensor 70 are not excluded. For example, the sensor 70 may be a pressure sensor that reads the pressure in a duct 20 suction, or a pressurized air duct, which flows into a point on the surface outer surface of the radially expandable plug 65.1, which under normal conditions operation is covered by the spindle or half-spindle. The pressure in the con- duct, read by the sensor, is a function of the presence or absence of the spindle that closes the end of the duct. If the sensor works with pressurized air, it is able to 25 detect a lack of pressure, or insufficient pressure in the duct if the man- The chuck (or semi-chuck) does not cover the end of the duct properly. If, however, the duct is aspirating, the sensor is able to detect the absence of the mandrel if the pressure in the duct is higher than a limit value.

[0093] In still further embodiments, the sensor may be a sensor 30 capacitive, capable of detecting the presence or absence of the spindle (or semi-spindle) on the radially expandable plug. In other embodiments the sensor may be a Page 21 of 29 Mannucci srl Office load sensor that reads a force or pressure exerted radially from the outside of the radially expandable pin, towards the axis of the radially expandable pin expandable. In the absence of a correctly positioned spindle, the force sensor or pressure reads an insufficient or zero load and is therefore able to signal the 5 failure to engage the spindle or half-spindle.

[0094] In still other embodiments, the sensor may comprise a micro- switch that is able to close a circuit if it cooperates with the spindle (or the semi- spindle) correctly engaged on the radially expanding pin. In the absence or loss of the spindle during extraction, the circuit in which the micro-switch is inserted 10 tore opens (or closes in case of reverse operation) and a alarm for loss or failure to grip the spindle by the radial pin expandable.

[0095] In further embodiments, the sensor 70 may be a video camera or a camera. In this case the sensor 70 photographs or records the portion of the ra- 15 dially expandable in which the mandrel, or semi-mandrel, must be present or not present in the case of the release phase of the expandable pin from the mandrel, or semi- spindle after extraction. The images or photographs taken by sensor 70 are processed through a vision algorithm which, for example, by comparing the im- images or videos detected with reference images or videos, discerns the presence or 20 absence of the spindle or semi-spindle from the radially expanding pin.

[0096] In still other embodiments, the sensor may be a photoelectric sensor. electric, a reflective photoelectric sensor, preferably a photoelectric sensor background suppression reflection. This last type of sensor is particularly advantageous in certain operating conditions, since through a triangulation not 25 evaluate only the light intensity reflected by the detected object, in this case the man- drino when present or the radially expandable plug, but they also detect the distance of the object from the sensor itself. The variation in distance detected by the sensor per- It therefore allows the presence or absence of the spindle to be detected radially on the pin expandable. 30

[0097] In general, and regardless of the nature and typology of the sensor used, such spindle is able to promptly report the lack of spindle on the Page 22 of 29 Mannucci srl Office radially expandable plug and can therefore provide, for example, to a con- control, a piece of information based on which the device in which the extractor is inserted can be arrested, or it can provide an alarm.

[0098] The spindle or half-spindle presence sensor can be used 5 in combination with gripping elements of other types and configured in a manner different than what is illustrated here.

[0099] In fact, the use of a socket element with a radially expanded plug The bile as described here has multiple advantages. For example, the grip of a mandrel tubular (whole or divided into two half-mandrels) allows the use of tubular mandrels of 10 simple shape, without the need to create projections, shanks or other gripping organs external. Furthermore, it is possible to grasp the mandrel even if the end of it does not protrude from the wrapped ribbon material that forms the roll. The grip from the inside is also less susceptible to mechanical damage to the spindle. Grasping the spindle tubular with a radially expandable plug can avoid the need for a 15 double gripping organ, with elements radially external to the spindle and ra- elements dially internal to the spindle. This makes the configuration of the gripping element simpler.

[0100] However, some at least of the advantages that are obtained by using a mon- designed to move with the gripping element and capable of detecting the presence of the 20 mandrels (in one piece or divided into two half-mandrels) are also obtained with ele- differently shaped sockets, for example with a locking system that acts from outside the spindle with an action directed from the outside towards the spindle axis.

[0101] In the preceding description the various embodiments and the different features of the extractor gripping element have been described with reference to 25 ment to a complex device, in which the extraction of the mandrels is combined with a roll accumulation system, and in which the extraction takes place simultaneously on a plurality of rolls coming from the accumulator (see Figs. 1 to 13). However, multiple features and advantageous embodiments of the spindle extractor and the The relative gripping element can also be used in manhole extraction devices. 30 differently shaped drini.

[0102] Figs. 19 and 20 schematically illustrate a different form of Page 23 of 29 Mannucci srl Office construction of a device for extracting mandrels from rolls of web material. The device is generally indicated with 101 and can be placed downstream of a station 103 of a transformer line. Station 103 may comprise, for example for example, a gluer to close the end flap of rolls coming from a rewinder 5 binatrice, not shown. The rolls R coming from the gluer 103 roll on a skid flight 105A, 105B, along which, in an intermediate position, a station is located of extraction of the spindles, indicated overall with 107. In the embodiment illustrated, device 101 is configured to extract two-piece mandrels, that is, made up of two half-spindles aligned axially with each other and coupled to two 10 ends facing each other and placed inside the roll R.

[0103] In the illustrated embodiment, the extraction station 107 is confi- designed to work one roll R at a time. The extraction station 107 may comprise provide a rotary distributor 109, capable of rotating in steps around an axis 109A.

[0104] The device 101 comprises two extractors 112 placed at the sides of the path of the 15 rolls R, as in this embodiment the device 101 is configured to extract half-mandrels, rather than a single-piece mandrel. Each extractor 112 may comprise a gripping element 113. Each gripping element 113 may comprise take a radially expandable plug 115. Each socket element 113 can be mounted on a slide 117. The two slides 117 are aligned on the two sides of the 20 extraction stations 107 and can each move according to the double arrow f117, for example along guides 119. The movement of the two slides 117 can be sin- chronological and mirror-image. The gripping elements 113 and the radially expanding pins 115 can be configured as the gripping elements 65 and the radially expanded pins 65.1 described above in one or more of the embodiments of Figs. 1 to 18. 25

[0105] Device 101 operates as follows. The rolls coming from the glue- Carrier 103 (or other upstream station) are stopped one at a time and in sequence in the extraction station 107. The gripping elements 113 engage the spindle M at the two ends of the roll R by means of a radial pin insertion movement expandable pins 115 and subsequent radial expansion of the radially expanded pins 30 hisses 115. Once the radially expandable pins 115 have firmly im- pegnate for expansion inside the two ends of the opposing half-mandrels M1, M2 which form the winding mandrel M, the two slides 117 are Page 24 of 29 Mannucci srl Office move them away from each other to remove the half-mandrels from the roll R. This can be appropriately maintained in position, avoiding translations in the axial direction, by means of stops 111 on both sides of the path of the rolls R (see Fig.19, omitted in Fig.20). Once the half-spindles M1, M2 have been extracted from the roll R which is 5 located in the extraction station 107, the rotating distributor 109 rotates to unload the roll R along slide 105B towards a valley station while the semi-spindles M1, M2 are conveyed to a downstream or upstream station, where they are re- mind coupled to form a winding mandrel that will be used for the formation tion of a new roll R. The station for joining or re-joining the two half-mandrels 10 can be integrated into a rewinder for winding R rolls which is not shown for descriptive simplicity.

[0106] While in Figs. 19 and 20 the rolls are held in position in the station extraction 107 through the rotated distributor 109 and the stops 111, it is understood that for perform this function of positioning and maintaining the rolls in position 15 different systems can be used, for example a cradle defined by rollers between their parallels, or otherwise.

[0107] It is understood from Figs. 19 and 20, that the above described characteristics of the gripping elements 65.1 can be used in very different extractor devices from each other. Page 25 of 29

Claims

CLAIMS 1. A gripper for withdrawing winding mandrels from rolls of wound web material, wherein the gripper comprises: an engagement member, adapted to engage a winding mandrel; and a sensor, movable with the gripper and configured to detect the presence of a winding mandrel engaged with the engagement member.

2. The gripping element of claim 1, wherein the sensor is integral with and carried by the gripping element.

3. The gripper element of claim 1 or 2, wherein the sensor is selected from the group comprising: a sensor adapted to detect a distance, a sensor adapted to detect a color, a sensor adapted to detect optical radiation reflected or backscattered from the spindle, a camera, a video camera, a force sensor, a pressure sensor, a photoelectric sensor, a reflective photoelectric sensor, a background suppression photoelectric sensor.

4. The gripping element of claim 1 or 2 or 3, wherein the sensor is an optical type sensor, wherein said optical type sensor is adapted to emit at least one optical beam in the direction of the engagement member.

5. The gripping member of any preceding claim, wherein the engaging member comprises a radially expandable pin configured to be inserted within a winding mandrel and engage the winding mandrel by expansion.

6. The gripping member of claim 5, wherein the radially expandable pin comprises a rod and at least one annular body surrounding said rod, the annular body being radially expandable about said rod, to pressurize an internal surface of the winding mandrel.

7. The gripping element of claim 6, 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.

8. The gripping element of claim 7, wherein the annular bodies are arranged on the rod free to slide relative to it.

9. The gripping element of claim 8 comprising, between adjacent annular bodies, a rigid annular element, slidably mounted on the rod.

10. The gripping element of any of claims 6 to 9, 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.

11. The gripper element of claim 10, wherein each annular body has a minimum energy configuration corresponding to a maximum axial dimension and a minimum radial dimension.

12. The gripping element of claim 10 or 11, wherein the rod comprises a radial end stop, such that 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.

13. The gripping member of any of claims 6 to 12, wherein the rod is housed in a slideway so as to slide axially in a slideway under the control of an expansion actuator, to move between an extension position and a retraction position relative to the slideway.

14. The gripping element of claim 5, wherein the radially expandable pin comprises at least one element radially expandable by a pressurized fluid, to pressurize an internal surface of the winding mandrel. Page 27 of 29 Ufficio Mannucci srl 15. A device for extracting winding mandrels from rolls of wound web material; wherein the device comprises: members for retaining a roll wound around a winding mandrel and from which the winding mandrel is to be extracted; and 5 an extraction assembly comprising at least one gripping element according to one or more of the preceding claims.

16. The device of claim 15, wherein the extraction group comprises two gripping elements according to one or more of the preceding claims, opposite to each other and coaxial, for simultaneously extracting two half-mandrels, forming the winding mandrel, from a roll wound around the winding mandrel.