Apparatus for making a coil winding and method for winding a coil

Abstract

An apparatus (1 ) for making a coil winding comprises a processing path (WP) comprising a loading zone (LZ), an unloading zone (DZ) and a reject zone (SZ); a plurality of collecting devices (5) movable along the processing path (WP) between the loading zone (LZ), the unloading zone (DZ) and the reject zone (SZ); at least one control device (16) configured to detect segments of defective strip- shaped elements (100); at least one winding spindle (14) configured to wind together a plurality of segments of strip-shaped elements (100). In the loading zone (LZ) each collecting device (5) is configured to receive and to wind a respective segment of strip-shaped element (100). In the unloading zone (DZ) each collecting device (5) is configured to unwind a segment of strip-shaped element (100) received that is not defective and to feed it towards said winding spindle (14). In the reject zone (SZ) each collecting device (5) is configured to reject a segment of strip-shaped element (100) received that is defective.

Description

[0001] DESCRIPTION

[0002] “Apparatus for making a coil winding and method for winding a coil”

[0003] The present invention refers to an apparatus for making a coil winding and to a method for winding a coil.

[0004] A coil winding, in the context of the present invention, is a spiral structure formed by winding strip-shaped elements around an axis, a flat surface or other winding structure. Depending on the structure around which the strip-shaped elements are wound, the shape of the coil winding can be substantially cylindrical or flattened or otherwise shaped.

[0005] The present invention can be applied in the field of the production of electrical energy accumulators such as electrochemical cells and capacitors within which coil winding structures can be used.

[0006] The present invention is particularly usable in the field of the production of electrochemical cells, for example secondary electrochemical cells, in which strip-shaped elements in the form of electrode foils and separator strips are wound together to make a coil winding. In the following, explicit reference will be made to the production of electrochemical cells.

[0007] One type of electrochemical cell that uses coil windings, called jelly roll or Swiss roll, provides that a strip-shaped separator is interposed between two electrode foils in the form of a strip, in particular an anode and a cathode, and that the multilayer composed of separator and electrode foils is wound to form an electrochemical cell in a cylindrical or almost cylindrical shape.

[0008] In the Applicant's experience, in order to make this type of electrochemical cells, winding apparatuses are used that provide a winding spindle rotatable about its own longitudinal axis. Free ends of the strip-shaped elements are associated with the winding spindle which is rotated around its own rotation axis, causing the winding of the strip-shaped elements between them and on the winding spindle.

[0009] In the Applicant's experience, the strip-shaped elements are unwound continuously from respective feeding coils and fed to the winding spindle by cutting the strip-shaped elements into segments after they have been fed to the winding spindle. The winding spindle is thus driven in rotation making the jelly roll type winding of the strip-shaped elements. Alternatively, segments of strip-shaped elements are cut from the feeding coils and wound on respective temporary collecting rollers. The temporary collecting rollers feed these segments of strip-shaped elements to the winding spindle. The winding spindle is driven in rotation making the jelly roll type winding of the stripshaped elements.

[0010] The coil winding obtained is then subjected to conformity checks configured to evaluate whether the coil winding obtained is suitable for making an electrochemical cell.

[0011] These conformity checks are necessary since the strip-shaped elements can present defects that, at least potentially, can negatively affect the correct operation of the electrochemical cell being produced.

[0012] In the Applicant's experience, one of such defects may be due to the presence of a junction in a segment of strip-shaped element. Each feeding coil of strip-shaped elements is in fact often made by joining together, through respective joints, two or more strips of strip-shaped elements. It may therefore happen that a segment of strip-shaped element comprises the final portion of a first strip and the initial portion of a second strip with the relative junction.

[0013] Further defects may be due to defects in the material coating the electrode foil segment, defects in the end notches of the electrode foil, incorrect lengths (or in any case not conforming to specifications) of the strip-shaped element.

[0014] The Applicant has verified that whenever a coil winding has at least one segment of strip-shaped element that is defective, it is necessary to reject or in any case eliminate such coil winding from the production line.

[0015] The Applicant has noted that rejecting defective coil windings inevitably leads to an increase in the production cost of the electrochemical cells.

[0016] The Applicant has also noted that rejecting defective coil windings has a negative environmental impact on the production processes of electrochemical cells linked to the resources (understood as raw materials and energy) used to produce coil windings that are not actually usable.

[0017] The Applicant has therefore perceived that it would be advantageous in economic terms (understood as a reduction in the production costs of electrochemical cells) and above all in environmental terms (understood as a lower environmental impact of the production processes of electrochemical cells) to be able to reuse or in any case re-introduce into other production processes the materials (understood as the raw materials) used to produce coil windings that are not actually usable.

[0018] In the Applicant's experience, it is possible to recover the rejected coil windings, disassemble these coil windings and reuse, recover or otherwise recycle the materials that make the segments of strip-shaped elements.

[0019] However, the Applicant has verified that although this allows to recover part of the raw materials used to produce coil windings that are not actually usable, the disassembly operations still require a use of resources in addition to the resources already used to produce coil windings that are not actually usable.

[0020] The Applicant has noted that if the resources needed to recover the raw materials used could be reduced, it would be possible to reduce the production costs of the electrochemical cells and reduce the environmental impact of the electrochemical cell production processes.

[0021] The Applicant has perceived that if the only segments of defective strip-shaped elements could be rejected from the production line, it would be possible to recover or in any case recycle the only segments of defective strip-shaped elements, avoiding having to recover and recycle an entire coil winding including also the segments of non-defective strip-shaped elements, with an obvious decrease in the resources necessary to recover the raw materials used.

[0022] The Applicant has found that by winding segments of strip-shaped elements on temporary collecting rollers it is possible to verify (directly or indirectly) the presence of any defects in the segments of strip-shaped elements wound on the temporary collecting rollers before segments of defective strip-shaped elements are wound together with other segments of strip-shaped elements, thus being able to reject and subsequently recover or in any case recycle the only segments of actually defective strip-shaped elements.

[0023] The present invention therefore concerns, in a first aspect thereof, an apparatus for making a coil winding.

[0024] Preferably, there is provided a processing path comprising a loading zone, an unloading zone and a reject zone. Preferably, there is provided a plurality of collecting devices movable along the processing path between the loading zone, the unloading zone and the reject zone.

[0025] Preferably, there is provided at least one control device configured to detect segments of defective strip-shaped elements.

[0026] Preferably, there is provided at least one winding spindle configured to wind together a plurality of segments of strip-shaped elements.

[0027] Preferably, in the loading zone each collecting device is configured to receive and to wind a respective segment of strip-shaped element.

[0028] Preferably, in the unloading zone each collecting device is configured to unwind a segment of strip-shaped element received that is not defective and to feed it towards said winding spindle.

[0029] Preferably, in the reject zone each collecting device is configured to reject a segment of strip-shaped element received that is defective.

[0030] The present invention concerns, in a second aspect thereof, a method for making a coil winding.

[0031] Preferably, it is provided to arrange a plurality of segments of strip-shaped elements.

[0032] Preferably, it is provided to wind segments of strip-shaped elements on respective collecting devices.

[0033] Preferably, it is provided to check whether the segments of strip-shaped elements wound or to be wound on the collecting devices have any defects.

[0034] Preferably, if all the segments of strip-shaped elements checked do not have defects, it is provided to unwind the segments of strip-shaped elements from the collecting devices and to feed them towards a winding spindle.

[0035] Preferably, if at least one segment of strip-shaped element checked has defects, it is provided to not unwind the segments of strip-shaped elements from the collecting devices to feed them towards the winding spindle and unwind only the segment of strip-shaped element that has defects from the respective collecting device to reject it. The Applicant has verified that by unwinding the segments of strip-shaped elements from the collecting devices towards the winding spindle only when all the segments of strip-shaped elements checked do not have defects, it is possible to guarantee that the coil winding made does not have defects (at least due to defects present in the individual segments of strip-shaped elements wound together).

[0036] The Applicant has also verified that by rejecting in the reject zone the only segments of strip-shaped elements that have defects, it is possible to recover these segments of strip-shaped elements that have defects so as to be able to recycle or regenerate them, and it is possible to rewind on the collecting devices (from which the segments of strip-shaped elements having defects have been made) new segments of strip-shaped elements so as to be able to complete a coil winding that does not have defects.

[0037] By “strip-shaped element” is meant a strip-shaped electrode foil or a strip-shaped separator.

[0038] By “strip-shaped foil” or “strip-shaped separator” is meant a strip having a dimension much larger than two further dimensions, wherein a first dimension of such two further dimensions is much larger than a second dimension of such two further dimensions. The strip can be monolithic or formed by a plurality of layers joined together made of identical material or different materials. The strip is also flexible.

[0039] By “segment” of strip-shaped element is meant a portion of strip-shaped element that has a beginning and an end. A segment of strip-shaped element may have a length comprised between 50 centimetres and 20 metres, preferably comprised between 1 metre and 15 metres, preferably comprised between 2 metres and 10 metres, preferably comprised between 3 metres and 8 metres, for example about 6 metres.

[0040] The present invention may have at least one of the preferred features described below. Such features may be present individually or in combination with each other, unless expressly stated otherwise, both in the apparatus and in the method of the present invention.

[0041] Preferably, said coil is intended for the storage of electrical energy.

[0042] Preferably, unwinding the segments of strip-shaped elements from the collecting devices and feeding them towards a winding spindle precedes making a coil winding.

[0043] Preferably, after making a coil winding, it is provided to remove the made coil winding from the processing path.

[0044] Preferably, said processing path is a closed path cyclically traversed by said plurality of collecting devices.

[0045] Preferably, the reject zone is placed, along the processing path, between said unloading zone and said loading zone.

[0046] Alternatively, the reject zone is placed, along the processing path, between said loading zone and said unloading zone.

[0047] Preferably, each collecting device cyclically travels along the processing path.

[0048] Preferably, each collecting device traverses in sequence the loading zone, the unloading zone and the reject zone, wherein the reject zone may be placed after the unloading zone or may be interposed between the loading zone and the unloading zone.

[0049] Preferably, when in the reject zone a collecting device rejects a segment of stripshaped element received that is defective, said segment of strip-shaped element received that is defective is unwound from the collecting device.

[0050] Preferably, a segment of strip-shaped element rejected in the reject zone is not directly used to make a coil winding.

[0051] Preferably, when a segment of defective strip-shaped element has been unwound from the respective collecting device and rejected, it is provided to wind a new segment of strip-shaped element only on the collecting device from which the defective strip-shaped element was unwound and rejected.

[0052] Preferably, winding a new segment of strip-shaped element only on the collecting device from which the defective strip-shaped element was unwound and rejected is implemented in the loading zone.

[0053] Preferably, it is provided to check whether the new segment of strip-shaped element wound or to be wound on the collecting device from which the defective strip-shaped element was unwound and rejected has any defects. Preferably, if the new segment of strip-shaped element wound or to be wound on the collecting device has no defects, it is provided to unwind the segments of strip-shaped elements from the collecting devices and feed them towards a winding spindle.

[0054] Preferably, if the new segment of strip-shaped element wound or to be wound on the collecting device has defects, it is provided not to unwind the segments of strip-shaped elements from the collecting devices to feed them towards the winding spindle and to unwind only the new segment of strip-shaped element that has defects from the respective collecting device to reject it.

[0055] Preferably, in the reject zone there is provided at least one picking device for picking a segment of rejected strip-shaped element.

[0056] Preferably, said at least one picking device comprises a winding roller.

[0057] Preferably the winding roller is configured to receive a segment of strip-shaped element from a collecting device.

[0058] Preferably, in the unloading zone it is provided to unwind a segment of defective strip-shaped element from a collecting device and wind said defective stripshaped element on the winding roller of the picking device.

[0059] Preferably, said control device is active at said loading zone.

[0060] Preferably, checking whether a segment of strip-shaped element has any defects precedes winding said segment of strip-shaped element on a respective collecting device.

[0061] Preferably, said control device is an electronic device configured to detect at least one characteristic of a segment of strip-shaped element.

[0062] Preferably, said characteristic of a segment of strip-shaped element may be an incision in the segment of strip-shaped element, the presence of a body or element foreign to the segment of strip-shaped element, the lack or even partial presence of active material for electrodes.

[0063] Preferably, said control device may be a video camera, a camera, a distance scanner, a spectrometer.

[0064] Preferably, there is provided a plurality of feeding lines of strip-shaped elements and a plurality of cutting devices, wherein each cutting device is active on a respective feeding line to make segments of strip-shaped elements.

[0065] Preferably, there is provided a plurality of transfer devices placed in said loading zone.

[0066] Preferably, each transfer device is configured to transfer a segment of stripshaped element to a collecting device.

[0067] Preferably, there is provided a plurality of control devices; the number of control devices being equal to the number of transfer devices.

[0068] Preferably, each control device is active at a respective transfer device.

[0069] Preferably, each collecting device comprises a retention device for retaining at least a portion of segment of strip-shaped element transferred by the transfer device and allowing the strip-shaped element to be wound onto the collecting device.

[0070] Preferably, only one type of segment of strip-shaped element is wound on each collecting device.

[0071] In a first embodiment, said plurality of collecting devices comprises a first group of collecting devices and a second group of collecting devices.

[0072] Preferably, each collecting device of the first group of collecting devices receives, in the loading zone, always the same type of strip-shaped element.

[0073] Preferably, each collecting device of the second group of collecting devices receives, in the loading zone, always the same type of strip-shaped element.

[0074] In this embodiment, the loading zone preferably comprises a first loading station and a second loading station.

[0075] Preferably, the first loading station is enslaved to the first group of collecting devices.

[0076] Preferably, the second loading station is enslaved to the second group of collecting devices.

[0077] In this embodiment, the unloading zone preferably comprises a first unloading station and a second unloading station. Preferably, the first unloading station is enslaved to the first group of collecting devices.

[0078] Preferably, the second unloading station is enslaved to the second group of collecting devices.

[0079] In this embodiment, the reject zone preferably comprises a first reject station and a second reject station.

[0080] Preferably, the first reject station is enslaved to the first group of collecting devices.

[0081] Preferably, the second reject station is enslaved to the second group of collecting devices.

[0082] Preferably, when a first collecting device of the first group of collecting devices is in the first loading station, a second collecting device of the first group of collecting devices is in the first unloading station and a third collecting device of the first group of collecting devices is in the first reject station.

[0083] Preferably, when a first collecting device of the second group of collecting devices is in the second loading station, a second collecting device of the second group of collecting devices is in the second unloading station and a third collecting device of the second group of collecting devices is in the second reject station.

[0084] A first feeding line of said plurality of feeding lines of strip-shaped elements is configured to feed a strip-shaped separator directly to the winding spindle.

[0085] A second feeding line of said plurality of feeding lines of strip-shaped elements is configured to feed a first strip-shaped electrode foil (for example a strip-shaped cathode electrode foil) to a collecting device of the first group of collecting devices placed in the first loading station.

[0086] A third feeding line of said plurality of feeding lines of strip-shaped elements is configured to feed a further strip-shaped separator directly to the winding spindle.

[0087] A fourth feeding line of said plurality of feeding lines of strip-shaped elements is configured to feed a second strip-shaped electrode foil (for example a stripshaped anode electrode foil) to a collecting device of the second group of collecting devices placed in the second loading station. In a second embodiment, there is preferably provided at least one collecting group comprising at least two collecting devices.

[0088] Preferably, said at least one collecting group comprises four collecting devices.

[0089] Preferably, the number of transfer devices is equal to the number of collecting devices of said at least one collecting group.

[0090] In the case where said at least one collecting group comprises four collecting devices, a first feeding line of said plurality of feeding lines of strip-shaped elements is configured to feed a strip-shaped separator, a second feeding line of said plurality of feeding lines of strip-shaped elements is configured to feed a first strip-shaped electrode foil (e.g., a strip-shaped cathode electrode foil), a third feeding line of said plurality of feeding lines of strip-shaped elements is configured to feed a further strip-shaped separator, and a fourth feeding line of said plurality of feeding lines of strip-shaped elements is configured to feed a second stripshaped electrode foil (e.g., a strip-shaped anode electrode foil).

[0091] Preferably, each collecting device of said at least one collecting group receives, in the loading zone, always the same type of strip-shaped element.

[0092] Preferably, said at least one collecting group further comprises a winding spindle.

[0093] Preferably, said at least one collecting group is movable along the processing path between the loading zone, the unloading zone and the reject zone.

[0094] Preferably, said at least one collecting group cyclically travels along the processing path.

[0095] Preferably, in the loading zone a respective segment of strip-shaped element is wound on all the collecting devices of said at least one collecting group.

[0096] Preferably, if all the segments of strip-shaped elements wound on the collecting devices of said at least one collecting group have no defects, it is provided to unwind all the segments of strip-shaped elements from the respective collecting devices of said at least one collecting group and feed them towards the winding spindle.

[0097] Preferably, if at least one segment of strip-shaped element wound on any collecting device of said at least one collecting group has defects, it is provided not to unwind any segment of strip-shaped element from the respective collecting device of said at least one collecting group towards the winding spindle.

[0098] Preferably, if at least one segment of strip-shaped element wound on any collecting device of said at least one collecting group has defects, it is provided to unwind the only defective segment of strip-shaped element from the collecting device and reject it.

[0099] Preferably, when a segment of defective strip-shaped element has been unwound from the respective collecting device and rejected, it is provided to wind a new segment of strip-shaped element only on the collecting device from which the defective strip-shaped element was unwound and rejected.

[0100] Preferably, it is provided to check whether the new segment of strip-shaped element wound or to be wound on the collecting device from which the defective strip-shaped element was unwound and rejected has any defects.

[0101] Preferably, there is provided a plurality of collecting groups in which each collecting group is movable along the processing path between the loading zone, the unloading zone and the reject zone.

[0102] Preferably, all the collecting groups have the same number of collecting devices.

[0103] Preferably, the winding spindle of each collecting group is configured to make a coil winding.

[0104] Preferably, the winding spindle of each collecting group is configured to make only one coil winding at a time.

[0105] Preferably, winding spindles of different collecting groups are configured to make coil windings distinct from each other.

[0106] Preferably, the collecting devices of a collecting group are configured to unwind segments of strip-shaped elements that do not have defects on the winding spindle of the same collecting group.

[0107] In a first variant of the second embodiment, the collecting devices of each collecting group are preferably movable with respect to said winding spindle at least when the collecting group is in the loading zone for simultaneously facing each collecting device to a respective transfer device.

[0108] In this embodiment variant, in the loading zone only one collecting group at a time is preferably present.

[0109] In a second variant of the second embodiment, the collecting devices of each collecting group are preferably movable with respect to said winding spindle at least when the collecting group is in the loading zone for facing one after the other each collecting device to a corresponding transfer device.

[0110] In this embodiment variant, in the loading zone four collecting groups are preferably present simultaneously.

[0111] Further characteristics and advantages of the present invention will become clearer from the following detailed description of a preferred embodiment thereof, with reference to the appended drawings and provided by way of indicative and non-limiting example, wherein: figures 1 to 3 are schematic views of an apparatus for making a coil winding in different operating conditions and according to a first embodiment in accordance with the present invention; figures 4 to 6 are schematic views of an apparatus for making a coil winding in different operating conditions and according to a first variant of a second embodiment according to the present invention; figures 7 to 9 are schematic views of an apparatus for making a coil winding in different operating conditions and according to a second variant of the second embodiment according to the present invention; figure 10 is a schematic view of some details of the apparatus according to the present invention; and figure 1 1 is a schematic perspective view of some details of the apparatus according to the present invention.

[0112] The representations in the accompanying figures do not necessarily have to be understood in scale and do not necessarily respect the proportions between the various parts.

[0113] The following description applies to all embodiments of the invention and to all variants of embodiments, except where expressly indicated.

[0114] The apparatus 1 is preferably used for winding together one or more segments of strip-shaped separators and strip-shaped electrode foils which are used to make electrochemical cells, for example secondary electrochemical cells.

[0115] The apparatus 1 comprises a plurality of feeding lines 2 for feeding strip-shaped elements 100 each of which is intended to form an anode electrode foil 101 , a cathode electrode foil 102 or a strip-shaped separator 103 of dielectric material. The strip-shaped elements 100 are fed by the plurality of feeding lines 2 in the form of continuous strips.

[0116] In the preferred embodiments of the invention, there are provided four feeding lines 2, for respectively feeding an anode electrode foil 101 , a cathode electrode foil 102 and two strip-shaped separators 103 of dielectric material.

[0117] The feeding lines 2 comprise coils 3 (illustrated only in figures 1 to 3) on each of which a respective strip-shaped element 100 is wound.

[0118] The apparatus 1 comprises a cutting device 4 for each feeding line 2 for cutting the strip-shaped element 100 which is unwound from the respective coil 3. The cutting device 4 can be a cutter or a rotating blade configured to cut a strip-shaped element 100 and make a segment thereof.

[0119] The apparatus 1 further comprises a plurality of collecting devices 5 each of which configured to receive and wind a segment of strip-shaped element 100 made available by a feeding line 2. Each collecting device 5 is rotatable about its own rotation axis at least while winding a respective segment of strip-shaped element 100. The rotation axes of the collecting devices 5 are all parallel to each other.

[0120] As schematically illustrated in figure 10, each collecting device 5 comprises a collecting roller 6 rotatable about a winding pin 7. The winding pin 7 develops along the rotation axis of the collecting device 5. The collecting roller 6 comprises an outer surface 8 configured to receive thereon a segment of strip-shaped element 100. Each collecting device 5 further comprises a retention device 9 activatable on a segment of strip-shaped element 100 to retain it during winding on the collecting device. The retention device 9 can for example be made by one or more aspirators 10 (a plurality of aspirators 10 is shown in figure 10 while only one aspirator 10 is shown in figure 1 1 ) placed on the outer surface 8 of the collecting roller 6.

[0121] In order to feed each segment of strip-shaped element 100 to the collecting devices 5, the apparatus 1 comprises a plurality of transfer devices 11 . Each transfer device 1 1 is fed with a strip-shaped element 100 from the respective feeding line 2. Each transfer device 1 1 is rotatable about its own rotation axis parallel to the rotation axis of the collecting devices 5. Each transfer device 1 1 comprises a transfer roller 12 rotatable about the rotation axis of the transfer device 1 1. The transfer roller 12 comprises an outer surface 13 (illustrated in figure 4) on which the strip-shaped element 100 is fed and retained. Each transfer device 12 may comprise a suction device (not illustrated) activatable on a portion of the strip-shaped element 100 to retain it. The suction device can for example be made by a plurality of aspirators distributed on the outer surface 13 of the transfer roller 12. The suction device has the task of retaining the strip-shaped element 100 during the rotation of the transfer device 1 1 .

[0122] A respective cutting device 4 is active at each transfer device 11 . The cutting device 4 can be placed immediately before the transfer device 11 (as in the example illustrated in figures 1 to 3) or it can be placed on the transfer device 1 1 (as in the examples illustrated in figures 4 to 9).

[0123] The apparatus 1 comprises at least one winding spindle 14 rotatable about its own rotation axis and configured to make a coil winding by winding together segments of strip-shaped elements 100. The rotation axis of the winding spindle

[0124] 14 is parallel to the rotation axis of the collecting devices 5. In the preferred embodiment of the invention, each winding spindle 14 is configured to wind together a segment of anode electrode foil 101 , a segment of cathode electrode foil 102, and two segments of strip-shaped separator 103. As schematically illustrated in figure 1 1 , each winding spindle 14 comprises two half-parts 15 that can be moved towards and away from each other to allow to the free end of a segment of strip-shaped element 100 to be inserted between the two half-parts

[0125] 15 (by moving the two half-parts 15 away) and to be retained between them (by bringing the two half-parts 15 closer).

[0126] The apparatus 1 comprises at least one control device 16 configured to detect segments of defective strip-shaped elements 100. The control device 16 has the function of detecting whether a segment of strip-shaped element 100 wound or to be wound on a respective collecting device 5 has defects that would negatively affect the coil winding made with (also) such segment of strip-shaped element.

[0127] The control device 16 (only schematized in the accompanying figures) is an electronic or mechanical device configured to detect at least one characteristic of a segment of strip-shaped element 100 that makes said segment of strip-shaped element 100 unsuitable for making a coil winding. Examples of characteristics that the control device 16 can, alternatively or in combination, detect are an incision in the segment of strip-shaped element 100, the presence of elements foreign to the segment of strip-shaped element 100 (such as for example a junction band), the even partial absence of active material for electrodes arranged on the segment of strip-shaped element 100. The control device 16 may for example be, alternatively or in combination, a video camera, a camera, a distance scanner, a spectrometer.

[0128] The control device 16 is placed in a position that allows the control device 16 to detect said characteristic of a segment of strip-shaped element 100. In the preferred embodiment of the invention, each control device 16 is active at a respective transfer device 1 1 . The control device 16 can be placed downstream of the cutting device 4 (as in the examples of figures 1 to 6) or upstream of the cutting device 4 (as in the example of figures 7 to 9).

[0129] The apparatus 1 comprises at least one picking device 17 configured to pick a segment of defective strip-shaped element 100 (i.e. unsuitable for making a coil winding). Each picking device 17 is configured to take a segment of defective strip-shaped element 100 from a collecting device 5 and remove it from said collecting device 5. In one embodiment, the picking device 16 comprises a winding roller 18. The winding roller 18 is rotatable about its own rotation axis. The winding roller 18 comprises an outer surface 19 on which the defective segments of strip-shaped element 100 is fed and retained. Each picking device 17 may comprise a suction device (not illustrated) activatable on the defective segment of strip-shaped element 100 to retain it and remove it from the collecting device 5. The suction device can for example be made by a plurality of aspirators distributed on the outer surface 19 of the winding roller 18.

[0130] The apparatus 1 comprises a processing path WP closed on itself and cyclically traversed by each collecting device 5. A loading zone LZ, an unloading zone DZ and a reject zone SZ are placed along the processing path WP. The reject zone SZ can be placed downstream of the unloading zone DZ (as illustrated in the accompanying figures) or it can be placed upstream of the unloading zone DZ along the processing path WP. The loading zone LZ precedes the unloading zone DZ along the processing path WP. When the reject zone SZ is placed downstream of the unloading zone DZ, the reject zone SZ is interposed between the unloading zone DZ and the loading zone LZ along the processing path WP. When the reject zone SZ is placed upstream of the unloading zone DZ, the reject zone SZ is interposed between the loading zone LZ and the unloading zone DZ along the processing path WP.

[0131] In the loading zone LZ the segments of strip-shaped elements 100 are wound on the collecting devices 5. The transfer devices 1 1 are permanently placed in the loading zone LZ. In the unloading zone DZ the segments of strip-shaped elements 100 are unwound from the collecting devices 5 and wound on the winding spindle 14 or on the winding spindles 14 (when more than one winding spindle 14 is provided). In the reject zone SZ, segments of defective strip-shaped elements 100 are unwound from the collecting devices 5 and rejected from the processing path WP. The at least one picking device 17 is permanently placed in the reject zone SZ.

[0132] In a first embodiment illustrated in figures 1 to 3, the collecting devices 5 comprise a first group of collecting devices 20 and a second group of collecting devices 21 . The loading zone LZ comprises a first loading station CS1 and a second loading station CS2. The unloading zone DZ comprises a first unloading station DS1 and a second unloading station DS2. The reject zone SZ comprises a first reject station SS1 and a second reject station SS2.

[0133] A first feeding line 2 feeds segments of strip-shaped elements 100, which in the illustrated example are segments of strip-shaped separator 103, to a winding spindle 14. The segments of strip-shaped separator 103 are obtained from the coil 3 of strip-shaped separator 103 by means of a cutting device 4 operating near the winding spindle 14.

[0134] The collecting devices 5 of the first group of collecting devices 20 cyclically transit through the first loading station CS1 , the first unloading station DS1 and the first reject station SS1 .

[0135] In the first loading station CS1 , a single collecting device 5 at a time receives from the corresponding transfer device 1 1 a segment of strip-shaped element 100, which in the illustrated example is a segment of cathode electrode foil 102. The segment of cathode electrode foil 102 is fed to the transfer device 1 1 from a second feeding line 2.

[0136] A third feeding line 2 feeds further segments of strip-shaped elements 100, which in the illustrated example are segments of strip-shaped separator 103, to the winding spindle 14. The segments of strip-shaped separator 103 are obtained from the coil 3 of strip-shaped separator 103 by means of a cutting device 4 operating near the winding spindle 14.

[0137] The collecting devices 5 of the second group of collecting devices 21 cyclically transit through the second loading station CS2, the second unloading station DS2 and the second reject station SS2.

[0138] In the second loading station CS2, a single collecting device 5 at a time receives from the corresponding transfer device 1 1 a segment of strip-shaped element 100, which in the illustrated example is a segment of anode electrode foil 101. The segment of cathode electrode foil is fed to the transfer device 1 1 from a fourth feeding line 2.

[0139] In a first variant of a second embodiment illustrated in figures 4 to 7, there is provided a plurality of collecting groups 22 each of which comprising four collecting devices 5. Each collecting group 22 further comprises a respective winding spindle 14.

[0140] The collecting groups 22 cyclically transport the respective collecting devices 5 along the processing path WP between the loading zone CZ, the unloading zone DZ and the reject zone SZ.

[0141] Four transfer devices 1 1 are arranged in the loading zone LZ, each of which operating on a respective feeding line 2. In particular, a first feeding line 2 feeds a strip-shaped separator 103, a second feeding line 2 feeds a cathode electrode foil 102, a third feeding line 2 feeds a further strip-shaped separator 103, and a fourth feeding line 2 feeds an anode electrode foil 101 .

[0142] At least when a collecting group 22 is in the unloading zone, the collecting devices 5 of said collecting group 22 are arranged around the respective winding spindle 14.

[0143] The collecting devices 5 of each collecting group 22, in addition to rotating about their respective rotation axes, are made movable between them and with respect to the winding spindle 14.

[0144] When a collecting group 22 is in the loading zone CZ, the respective collecting devices 5 are arranged so that each simultaneously faces a respective transfer device 1 1 .

[0145] In the loading zone LZ there is only one collecting group 22 at a time. When a collecting group 22 is in the unloading zone SZ, the respective collecting devices 5 are arranged in such a way as to face in succession a single picking device 17 (as illustrated in figures 1 to 3) or to face each a respective picking device 17.

[0146] In a second variant of the second embodiment (illustrated in figures 7 to 9), there is provided a plurality of collecting groups 22 each of which comprising four collecting devices 5. Each collecting group 22 further comprises a respective winding spindle 14.

[0147] The collecting groups 22 cyclically transport the respective collecting devices 5 along the processing path WP between the loading zone CZ, the unloading zone DZ and the reject zone SZ.

[0148] Four transfer devices 1 1 are arranged in the loading zone LZ, each of which operating on a respective feeding line 2. In particular, a first feeding line 2 feeds a strip-shaped separator 103, a second feeding line 2 feeds a cathode electrode foil 102, a third feeding line 2 feeds a further strip-shaped separator 103, and a fourth feeding line 2 feeds an anode electrode foil 101 .

[0149] The collecting devices 5 of a same collecting group 22 are always arranged around the respective winding spindle 14.

[0150] Each collecting group 22 is made rotatable, together with the respective collecting devices 5 around a rotation axis parallel to the rotation axes of the collecting devices 5 and preferably passing through the winding spindle 14.

[0151] When a collecting group 22 is in the loading zone CZ, it is put in rotation around its own rotation axis to face in succession and at successive times the respective collecting devices 5 to the transfer devices 1 1 . A first collecting device 5 of a collecting group 22 is made to face a first transfer device 1 1 for receiving a first segment of strip-shaped element 100, then a second collecting device 5 of the same collecting group 22 is made to face a second transfer device 1 1 for receiving a second segment of strip-shaped element 100, then a third collecting device 5 of the same collecting group 22 is made to face a third transfer device 11 for receiving a third segment of strip-shaped element 100 and then a fourth collecting device 5 of the same collecting group 22 is made to face a fourth transfer device 1 1 for receiving a fourth segment of strip-shaped element 100.

[0152] In the loading zone LZ there are four collecting groups 22 simultaneously. When a collecting group 22 is in the unloading zone SZ, it is rotated around its own rotation axis to face a collecting device 5 from which a defective strip-shaped element 100 must be unloaded to the picking device 17 (as illustrated in figures 7 to 9). Alternatively, when a collecting group 22 is in the unloading zone SZ, it is rotated around its own rotation axis to subsequently face all the collecting devices 5 to four picking devices 17 arranged in succession.

[0153] A method for making a coil winding according to the present invention provides to wind segments of strip-shaped elements 100 on respective collecting devices 5. This action is carried out in the loading zone LZ.

[0154] Each segment of strip-shaped element 100 wound or to be wound on the respective collecting device 5 is checked for the presence of any defects that would negatively affect the coil winding. This action is implemented by the control devices 16.

[0155] If all the segments of strip-shaped elements 100 checked that must be wound to form a single coil winding have no defects, it is provided to unwind the segments of strip-shaped elements 100 from the collecting devices 5 and feed them towards the winding spindle 14. This action is carried out in the unloading zone DZ.

[0156] If at least one segment of strip-shaped element 100 checked has defects, it is provided not to unwind any of the segments of strip-shaped elements 100 that will have to form a coil winding from the collecting devices 5. In this case, it is provided to unwind only the segment of strip-shaped element that has defects from the respective collecting device 5 to reject it and leave the segments of stripshaped elements 100 having no defects wound on the respective collecting devices 5. This action is carried out in the reject zone SZ.

[0157] The method for making a coil winding further provides, when a segment of defective strip-shaped element 100 has been unwound from the respective collecting device 5 and rejected, to wind a new segment of strip-shaped element 100 (of the same type as the rejected strip-shaped element 100) only on the collecting device 5 from which the defective strip-shaped element 100 was unwound and rejected. This action is carried out in the loading zone LZ. During this action, no further strip-shaped elements 100 are wound on the collecting devices 5 from which no strip-shaped elements 100 have been unwound.

[0158] With particular reference to the first embodiment, the winding on respective collecting devices 5 of segments of strip-shaped elements 100 is implemented by bringing a single collecting device 5 of the first group of collecting devices 20 into the loading zone LZ. In particular, the collecting device 5 of the first group of collecting devices 20 is brought into the first loading station CS1. From the second feeding line 2 a segment of cathode electrode foil 102 is cut from the coil 3. The segment of cathode electrode foil 102 is wound on the collecting device 5 of the first group of collecting devices 20 by putting the collecting device 5 in rotation about its own rotation axis.

[0159] Simultaneously, one single collecting device 5 of the second group of collecting devices 21 is brought into the loading zone LZ. In particular, the collecting device 5 of the second group of collecting devices 21 is brought into the second loading station CS2. From the fourth feeding line 2, a segment of anode electrode foil 101 is cut from the coil 3. The segment of anode electrode foil 101 is wound on the collecting device 5 of the second group of collecting devices 21 by putting the collecting device 5 in rotation about its rotation axis.

[0160] Checking each segment of strip-shaped element 100 wound or to be wound on the respective collecting device 5 is implemented by checking whether the single segment of anode electrode foil 101 and the single segment of cathode electrode foil 102 have defects.

[0161] Subsequently, the collecting device 5 of the first group of collecting devices 20 is brought into the unloading zone DZ. In particular, the collecting device 5 of the first group of collecting devices 20 is brought into the first unloading station DS1 .

[0162] Simultaneously, the collecting device 5 of the second group of collecting devices 21 is brought into the unloading zone DZ. In particular, the collecting device 5 of the second group of collecting devices 21 is brought into the second unloading station DS2.

[0163] If both the checked segment of anode electrode foil 101 and the checked segment of cathode electrode foil 102 have no defects, the segment of anode electrode foil 101 and the segment of cathode electrode foil 102 are unwound from the collecting devices 5 and fed to the winding spindle 14.

[0164] Simultaneously, two segments of strip-shaped separators 103 are cut from the first feeding line 2 and the third feeding line 2 and fed to the winding spindle 14.

[0165] The winding spindle 14 winds together the four strip-shaped elements 100, making a coil winding. If at least one of the checked segment of anode electrode foil 101 and the checked segment of cathode electrode foil 102 has defects, the collecting device 5 of the first group of collecting devices 20 and the collecting device 5 of the second group of collecting devices 21 are brought into the reject zone SZ without having fed the winding spindle 14 with the respective segment of anode electrode foil 101 and segment of cathode electrode foil 102. In particular, the collecting device 5 of the first group of collecting devices 20 is brought into the first reject station SS1 and the collecting device 5 of the second group of collecting devices 21 is brought into the second reject station SS2.

[0166] In this case, no segments of strip-shaped separators 103 are cut from the first feeding line 2 and the third feeding line 2, and no segments of strip-shaped separators 103 are fed to the winding spindle 14.

[0167] Unwinding only the segment of strip-shaped element that has defects from the respective collecting device 5 to reject it and leave the segments of strip-shaped elements 100 that have no defects wound on the respective collecting devices 5 is implemented as follows.

[0168] If the segment of anode electrode foil 101 is defective and the segment of cathode electrode foil 102 is not defective, the segment of anode electrode foil 101 is unwound from the collecting device 5 of the second group of collecting devices 21 and rejected. The segment of cathode electrode foil 102 remains wound on the collecting device 5 of the first group of collecting devices 20.

[0169] If the segment of cathode electrode foil 102 is defective and the segment of anode electrode foil 101 is not defective, the segment of cathode electrode foil 102 is unwound from the collecting device 5 of the first group of collecting devices 20 and rejected. The segment of anode electrode foil 101 remains wound on the collecting device 5 of the second group of collecting devices 21 .

[0170] If both the segment of cathode electrode foil 102 and the segment of anode electrode foil 101 are defective, the segment of cathode electrode foil 102 is unwound from the collecting device 5 of the first group of collecting devices 20 and rejected and the segment of anode electrode foil 101 is unwound from the collecting device 5 of the second group of collecting devices 21 and rejected.

[0171] Winding a new segment of strip-shaped element 100 (of the same type as the rejected strip-shaped element 100) only on the collecting device 5 from which the defective strip-shaped element 100 was unwound and rejected is implemented as follows.

[0172] The collecting device 5 of the first group of collecting devices 20 is brought again into the loading zone LZ. In particular, the collecting device 5 of the first group of collecting devices 20 is brought into the first loading station CS1. The collecting device 5 of the second group of collecting devices 21 is brought into the loading zone LZ. In particular, the collecting device 5 of the second group of collecting devices 21 is brought into the second loading station CS2.

[0173] If the single segment of cathode electrode foil 102 was rejected, a new segment of cathode electrode foil 102 is wound on the collecting device 5 of the first group of collecting devices 20 in the same manners as described above. On the collecting device 5 of the second group of collecting devices 21 (which continues to have a segment of anode electrode foil 101 wound around itself) no new segment of anode electrode foil 101 is wound.

[0174] If the single segment of anode electrode foil 101 was rejected, a new segment of anode electrode foil 101 is wound on the collecting device 5 of the second group of collecting devices 21 in the same manners as described above. On the collecting device 5 of the first group of collecting devices 20 (which continues to have a segment of cathode electrode foil 102 wound on itself) no new segment of cathode electrode foil 102 is wound.

[0175] If both the segment of anode electrode foil 101 and the segment of cathode electrode foil 102 have been rejected, a new segment of anode electrode foil 101 is wound on the collecting device 5 of the second group of collecting devices 21 in the same manners as described above and a new segment of cathode electrode foil 102 is wound on the collecting device 5 of the first group of collecting devices 20 in the same manners as described above.

[0176] Figure 1 illustrates the apparatus 1 in use at a time instant (i.e. how the apparatus 1 appears during its operation in a minimum fraction of time). Figure 1 depicts a plurality of collecting devices 5 of the first group of collecting devices 20 and of the second group of collecting devices 21 , each of which occupying a position along the processing path WP. In the loading zone LZ there are depicted two collecting devices 5 on which two respective different segments of strip-shaped elements 100 are being wound. In the unloading zone DZ there are depicted two further collecting devices 5 which are feeding two respective segments of stripshaped elements 100 to the winding spindle 14. Two further segments of segments of strip-shaped elements 100 are also fed to the winding spindle 14 to make a coil winding. In the reject zone SZ there are depicted further two collecting devices 5 in which one collecting device is unloading a defective segment of stripshaped element 100 and in which the other collecting device has a segment of strip-shaped element 100 wound that must not be rejected. Between the loading zone LZ and the unloading zone DZ there are depicted further two collecting devices 5 that are moving from the loading zone LZ to the unloading zone DZ. Between the reject zone SZ and the loading zone LZ there are depicted further two collecting devices 5 that are moving from the reject zone SZ to the loading zone LZ.

[0177] Figure 2 illustrates the apparatus 1 in use in which successive time instants have been represented to show a sequence of actions. Figure 2 illustrates an example in which all the segments of strip-shaped elements have no defects and are suitable for making a coil winding. Figure 2 depicts a single collecting device 5 of the first group of collecting devices 20 and a single collecting device 5 of the second group of collecting devices 21 that transit along the processing path WP. In the loading zone LZ there are depicted the two collecting devices 5 on which two different segments of strip-shaped elements 100 are being wound. In the unloading zone DZ there are depicted the two collecting devices 5 that are feeding segments of strip-shaped elements 100 to the winding spindle 14. Two further segments of segments of strip-shaped elements 100 are also fed to the winding spindle 14 to make a coil winding. In the reject zone SZ there are depicted the two collecting devices 5 on which the segments of strip-shaped elements 100 are no longer wound (as they are already used to make the coil winding). Between the loading zone LZ and the unloading zone DZ there are depicted the two collecting devices 5 that are moving from the loading zone LZ to the unloading zone DZ. Between the reject zone SZ and the loading zone LZ there are depicted the two collecting devices 5 that are moving from the reject zone SZ to the loading zone LZ.

[0178] Figure 3 illustrates the apparatus 1 in use in which successive time instants have been represented to show a sequence of actions. Figure 3 illustrates an example in which a segment of strip-shaped element has defects. Figure 3 depicts a single collecting device 5 of the first group of collecting devices 20 and a single collecting device 5 of the second group of collecting devices 21 that transit along the processing path WP. In the unloading zone DZ there are depicted the two collecting devices 5 that are not feeding segments of strip-shaped elements 100 to the winding spindle 14 since a segment of strip-shaped element 100 has been identified as defective. Neither the two further segments of segments of stripshaped elements 100 are fed to the winding spindle 14. In the reject zone SZ there is depicted a collecting device 5 which has a segment of strip-shaped element 100 wound and not having defects and in which the other collecting device 5 is rejecting a defective segment of strip-shaped element 100. In the loading zone LZ there are depicted the two collecting devices 5 in which a new segment of strip-shaped element 100 of the same type previously rejected is being wound only on the collecting device 5 from which the segment of stripshaped element 100 was rejected.

[0179] With particular reference to the first variant of the second embodiment, the winding on respective collecting devices 5 of segments of strip-shaped elements 100 is implemented as follows.

[0180] A collecting group 22 is brought into the loading zone LZ and the collecting devices 5 of this collecting group 22 are moved to arrange each collecting device 5 at a respective transfer device 11 . A segment of strip-shaped separator 103 cut from the first feeding line 2 is wound on a first collecting device 5. A segment of cathode electrode foil 102 cut from the second feeding line 2 is wound on a second collecting device 5. A segment of strip-shaped separator 103 cut from the third feeding line 2 is wound on a third collecting device 5. A segment of anode electrode foil 101 cut from the fourth feeding line 2 is wound on a fourth collecting device 5. The windings on the respective collecting devices 5 of the strip-shaped elements 100 take place simultaneously.

[0181] Checking each segment of strip-shaped element 100 wound or to be wound on the respective collecting device 5 is implemented by checking whether at least the segment of anode electrode foil 101 and the segment of cathode electrode foil 102 have defects. Preferably, it is checked whether also the segments of stripshaped separator 103 have defects.

[0182] Subsequently, the collecting group 22 is brought into the unloading zone DZ. During this operation, the collecting devices 5 of the collecting group 22 are moved to arrange the collecting devices 5 around the winding spindle 14.

[0183] If all the checked segments of strip-shaped elements 100 have no defects, the segment of anode electrode foil 101 , the segment of cathode electrode foil 102 and the two segments of strip-shaped separator 103 are unwound from the respective collecting devices 5 and fed towards the winding spindle 14.

[0184] The winding spindle 14 winds together the four strip-shaped elements 100, making a coil winding.

[0185] Unwinding only the segment of strip-shaped element that has defects from the respective collecting device 5 to reject it and leave the segments of strip-shaped elements 100 that have no defects wound on the respective collecting devices 5 is implemented as follows.

[0186] The collecting group 22 is brought into the reject zone SZ and the collecting devices 5 of the collecting group 22 are moved to arrange in succession the collecting devices 5 at the picking device 17 (as illustrated in figures 4 to 7). Alternatively, the collecting devices 5 of the collecting group 22 are moved for each collecting device 5 at a respective picking device 17.

[0187] If there is only one segment of strip-shaped element 100 that is defective, this defective segment of strip-shaped element 100 is unwound from the respective collecting device 5 and rejected. The other segments of strip-shaped elements 100 remain wound on the respective collecting devices 5.

[0188] If more than one defective segment of strip-shaped element 100 are present, such defective segments of strip-shaped elements 100 are unwound in succession (in the case of a single picking device 17) or simultaneously (in the case of four picking devices 17) from the respective collecting devices 5 and rejected. The non-defective segment of strip-shaped element 100 or the other non-defective segment of strip-shaped element 100 remain wound on the respective collecting devices 5.

[0189] Winding a new segment of strip-shaped element 100 (of the same type as the rejected strip-shaped element 100) only on the collecting device 5 from which the defective strip-shaped element 100 was unwound and rejected is implemented as follows.

[0190] The collecting group 22 is brought again into the loading zone LZ and the collecting devices 5 of the collecting group 22 are moved to arrange each collecting device 5 at a respective transfer device 11 . This action is carried out by arranging the collecting devices 5 in the same order and in the same correspondence with the transfer devices 1 1 previously implemented. A new strip-shaped element 100 of the same type previously rejected is wound on the collecting devices without the strip-shaped element 100. In particular, if a segment of strip-shaped separator 103 was rejected by the first collecting device 5, a new segment of strip-shaped separator 103 is wound on the first collecting device. If a segment of cathode electrode foil 102 was rejected by the second collecting device 5, a new segment of cathode electrode foil 102 is wound on the second collecting device. If a segment of strip-shaped separator 103 was rejected by the third collecting device 5, a new segment of strip-shaped separator 103 is wound on the third collecting device. If a segment of anode electrode foil 101 was rejected by the fourth collecting device 5, a new segment of anode electrode foil 101 is wound on the fourth collecting device.

[0191] No new strip-shaped element 100 is wound on the collecting devices still provided with strip-shaped elements 100.

[0192] Figure 4 illustrates the apparatus 1 in use at a time instant (i.e. how the apparatus 1 appears during its operation in a minimum fraction of time). Figure 4 depicts a plurality of collecting groups 22 each of which occupying a position along the processing path WP. In the loading zone LZ there are depicted four collecting devices 5 of a first collecting group 22 on which four different segments of stripshaped elements 100 are being wound. In the unloading zone DZ there are depicted four collecting devices 5 of a second collecting group 22 which are feeding segments of strip-shaped elements 100 to the winding spindle 14 to make a coil winding. In the reject zone SZ there are depicted four collecting devices 5 of a third collecting group 22 in which a collecting device is unloading a defective segment of strip-shaped element 100. Between the loading zone LZ and the unloading zone DZ there is depicted a further collecting group which is moving from the loading zone LZ to the unloading zone DZ. Between the unloading zone DZ and the reject zone SZ there is depicted a further collecting group in which the segments of strip-shaped elements 100 have already been unwound from the respective collecting devices and in which a coil winding has already been made and is ready to be removed from the processing path WP.

[0193] Figure 5 illustrates the apparatus 1 in use in which successive time instants have been represented to show a sequence of actions. Figure 5 illustrates an example in which all the segments of strip-shaped elements have no defects and are suitable for making a coil winding. Figure 5 depicts a single collecting group 22 that transits along the processing path WP. In the loading zone LZ there are depicted four collecting devices 5 of the collecting group 22 on which four different segments of strip-shaped elements 100 are being wound. In the unloading zone DZ there are depicted four collecting devices 5 of the collecting group 22 which are feeding segments of strip-shaped elements 100 to the winding spindle 14 to make a coil winding. In the reject zone SZ there are depicted the four collecting devices 5 of the collecting group 22 on which the segments of strip-shaped elements 100 are no longer wound (as they are already used to make the coil winding). Between the loading zone LZ and the unloading zone DZ there is depicted the collecting group which is moving from the loading zone LZ to the unloading zone DZ. Between the unloading zone DZ and the reject zone SZ there is depicted the collecting group in which the segments of strip-shaped elements 100 have already been unwound from the respective collecting devices and in which a coil winding has already been made and is ready to be removed from the processing path WP.

[0194] Figure 6 illustrates the apparatus 1 in use in which successive time instants have been represented to show a sequence of actions. Figure 6 illustrates an example in which a segment of strip-shaped element has defects. Figure 6 depicts a single collecting group 22 that transits along the processing path WP. In the unloading zone DZ there are depicted the four collecting devices 5 of the collecting group 22 which are not feeding segments of strip-shaped elements 100 to the winding spindle 14 since a segment of strip-shaped element 100 has been identified as defective. In the reject zone SZ there are depicted four collecting devices 5 of the collecting group 22 in which three collecting devices have wound segments of strip-shaped elements having no defects and in which a collecting device 5 is rejecting a defective segment of strip-shaped element 100. In the loading zone LZ there are depicted the four collecting devices 5 of the collecting group 22 in which a new segment of strip-shaped element 100 of the same type previously rejected is being wound only on the collecting device 5 from which a segment of strip-shaped element 100 was rejected.

[0195] With particular reference to the second variant of the second embodiment, the winding on respective collecting devices 5 of segments of strip-shaped elements 100 is implemented as follows.

[0196] A collecting group 22 is brought into the loading zone LZ and the collecting devices 5 of this collecting group 22 are arranged in succession and at successive times at respective transfer devices 11 . A segment of strip-shaped separator 103 cut from the first feeding line 2 is wound on a first collecting device 5. A segment of cathode electrode foil 102 cut from the second feeding line 2 is wound on a second collecting device 5. A segment of strip-shaped separator 103 cut from the third feeding line 2 is wound on a third collecting device 5. A segment of anode electrode foil 101 cut from the fourth feeding line 2 is wound on a fourth collecting device 5. The windings on the respective collecting devices 5 of the strip-shaped elements 100 take place simultaneously.

[0197] Checking each segment of strip-shaped element 100 wound or to be wound on the respective collecting device 5 is implemented by checking whether at least the segment of anode electrode foil 101 and the segment of cathode electrode foil 102 have defects. Preferably, it is checked whether also the segments of stripshaped separator 103 have defects.

[0198] Subsequently, the collecting group 22 is brought into the unloading zone DZ. During this operation, the collecting devices 5 of the collecting group 22 are moved to arrange the collecting devices 5 around the winding spindle 14.

[0199] If all the checked segments of strip-shaped elements 100 have no defects, the segment of anode electrode foil 101 , the segment of cathode electrode foil 102 and the two segments of strip-shaped separator 103 are unwound from the respective collecting devices 5 and fed towards the winding spindle 14.

[0200] The winding spindle 14 winds together the four strip-shaped elements 100, making a coil winding.

[0201] Unwinding only the segment of strip-shaped element that has defects from the respective collecting device 5 to reject it and leave the segments of strip-shaped elements 100 that have no defects wound on the respective collecting devices 5 is implemented as follows.

[0202] The collecting group 22 is brought into the reject zone SZ and the collecting devices 5 of the collecting group 22 are brought in succession and at successive times at the picking device 17.

[0203] If there is only one segment of strip-shaped element 100 that is defective, this defective segment of strip-shaped element 100 is unwound from the respective collecting device 5 and rejected. The other segments of strip-shaped elements 100 remain wound on the respective collecting devices 5.

[0204] If more than one defective segment of strip-shaped element 100 are present, such defective segments of strip-shaped elements 100 are unwound in succession from the respective collecting devices 5 and rejected. The nondefective segment of strip-shaped element 100 or the other non-defective segment of strip-shaped element 100 remain wound on the respective collecting devices 5.

[0205] Winding a new segment of strip-shaped element 100 (of the same type as the rejected strip-shaped element 100) only on the collecting device 5 from which the defective strip-shaped element 100 was unwound and rejected is implemented as follows.

[0206] The collecting group 22 is brought again into the loading zone LZ and the collecting devices 5 of the collecting group 22 are arranged in succession and at successive times at respective transfer devices 1 1. at a respective transfer device 1 1 . This action is carried out by bringing the collecting devices 5 in the same order and in the same correspondence with the transfer devices 1 1 previously implemented.

[0207] A new strip-shaped element 100 of the same type previously rejected is wound on the collecting devices without the strip-shaped element 100. In particular, if a segment of strip-shaped separator 103 was rejected by the first collecting device 5, a new segment of strip-shaped separator 103 is wound on the first collecting device. If a segment of cathode electrode foil 102 was rejected by the second collecting device 5, a new segment of cathode electrode foil 102 is wound on the second collecting device. If a segment of strip-shaped separator 103 was rejected by the third collecting device 5, a new segment of strip-shaped separator 103 is wound on the third collecting device. If a segment of anode electrode foil 101 was rejected by the fourth collecting device 5, a new segment of anode electrode foil 101 is wound on the fourth collecting device.

[0208] No new strip-shaped element 100 is wound on the collecting devices still provided with strip-shaped elements 100.

[0209] Figure 7 illustrates the apparatus 1 in use at a time instant (i.e. how the apparatus 1 appears during its operation in a minimum fraction of time). Figure 4 depicts a plurality of collecting groups 22 each of which occupying a position along the processing path WP. In the loading zone LZ there are depicted four collecting groups 22 in which on a collecting device 5 of each collecting group 22 a respective segment of strip-shaped element 100 is being wound. In the unloading zone DZ there are depicted four collecting devices 5 of a further collecting group 22 which are feeding segments of strip-shaped elements 100 to the winding spindle 14 to make a coil winding. In the reject zone SZ there are depicted four collecting devices 5 of a further third collecting group 22 in which a collecting device 5 is unloading a defective segment of strip-shaped element 100. Between the loading zone LZ and the unloading zone DZ there is depicted a further collecting group which is moving from the loading zone LZ to the unloading zone DZ. Between the unloading zone DZ and the reject zone SZ there is depicted a further collecting group in which the segments of strip-shaped elements 100 have already been unwound from the respective collecting devices and in which a coil winding has already been made and is ready to be removed from the processing path WP.

[0210] Figure 8 illustrates the apparatus 1 in use in which successive time instants have been represented to show a sequence of actions. Figure 8 illustrates an example in which all the segments of strip-shaped elements have no defects and are suitable for making a coil winding. Figure 8 depicts a single collecting group 22 that transits along the processing path WP. In the loading zone LZ there are depicted the successive time phases in which the four collecting devices 5 of the collecting group 22 receive four different segments of strip-shaped elements 100. In the unloading zone DZ there are depicted four collecting devices 5 of the collecting group 22 which are feeding segments of strip-shaped elements 100 to the winding spindle 14 to make a coil winding. In the reject zone SZ there are depicted the four collecting devices 5 of the collecting group 22 on which the segments of strip-shaped elements 100 are no longer wound (as they are already used to make the coil winding). Between the loading zone LZ and the unloading zone DZ there is depicted the collecting group which is moving from the loading zone LZ to the unloading zone DZ. Between the unloading zone DZ and the reject zone SZ there is depicted the collecting group in which the segments of stripshaped elements 100 have already been unwound from the respective collecting devices and in which a coil winding has already been made.

[0211] Figure 9 illustrates the apparatus 1 in use in which successive time instants have been represented to show a sequence of actions. Figure 9 illustrates an example in which a segment of strip-shaped element has defects. Figure 9 depicts a single collecting group 22 that transits along the processing path WP. In the unloading zone DZ there are depicted the four collecting devices 5 of the collecting group 22 which are not feeding segments of strip-shaped elements 100 to the winding spindle 14 since a segment of strip-shaped element 100 has been identified as defective. In the reject zone SZ there are depicted four collecting devices 5 of the collecting group 22 in which three collecting devices have wound segments of strip-shaped elements having no defects and in which a collecting device 5 is rejecting a defective segment of strip-shaped element 100. In the loading zone LZ there are depicted the four successive time phases in which the four collecting devices 5 of the collecting group 22 face the respective transfer devices 1 1 and in which a new segment of strip-shaped element 100 of the same type previously rejected is wound only on the collecting device 5 from which a segment of stripshaped element 100 was rejected.

Claims

CLAIMS1. Apparatus (1 ) for making a coil winding comprising: a processing path (WP) comprising a loading zone (LZ), an unloading zone (DZ) and a reject zone (SZ); a plurality of collecting devices (5) movable along the processing path (WP) between the loading zone (LZ), the unloading zone (DZ) and the reject zone (SZ); at least one control device (16) configured to detect segments of defective stripshaped elements (100); at least one winding spindle (14) configured to wind together a plurality of segments of strip-shaped elements (100); wherein in the loading zone (LZ) each collecting device (5) is configured to receive and to wind a respective segment of strip-shaped element (100); wherein in the unloading zone (DZ) each collecting device (5) is configured to unwind a segment of strip-shaped element (100) received that is not defective and to feed it towards said winding spindle (14); wherein in the reject zone (SZ) each collecting device (5) is configured to reject a segment of strip-shaped element (100) received that is defective.

2. Apparatus (1 ) according to claim 1 , wherein said control device (16) is active at said loading zone (LZ).

3. Apparatus (1 ) according to claim 1 or 2, comprising a plurality of feeding lines (2) of strip-shaped elements (100) and a plurality of cutting devices (4), wherein each cutting device (4) is active on a respective feeding line (2) to make segments of strip-shaped elements (100).

4. Apparatus (1 ) according to any one of the preceding claims, comprising a plurality of transfer devices (1 1 ) placed in said loading zone (LZ); each transfer device (1 1 ) being configured to transfer a segment of strip-shaped element (100) to a collecting device (5).

5. Apparatus (1 ) according to claim 4, comprising a plurality of control devices (16); the number of control devices (16) being equal to the number of transfer devices (1 1 ).

6. Apparatus (1 ) according to any one of the preceding claims, wherein said processing path (WP) is a closed path cyclically traversed by said plurality ofcollecting devices (5).

7. Apparatus (1 ) according to claim 6, wherein said reject zone (SZ) is placed, along the processing path (WP), between said unloading zone (DZ) and said loading zone (LZ).

8. Apparatus (1 ) according to claim 6, wherein said reject zone (SZ) is placed, along the processing path (WP), between said loading zone (LZ) and said unloading zone (DZ).

9. Apparatus (1 ) according to any one of the preceding claims, comprising a plurality of collecting groups (22) wherein each collecting group (22) comprises at least two collecting devices (5) and a winding spindle (14); each collecting group (22) being movable along the processing path (WP) between the loading zone (LZ), the unloading zone (DZ) and the reject zone (SZ).

10. Apparatus (1 ) according to claims 2 and 9, wherein the collecting devices (5) of each collecting group (22) are movable with respect to said winding spindle (14) at least when the collecting group (22) is in the loading zone (LZ) for simultaneously facing each collecting device (5) to a respective transfer device (1 1 ).11 . Apparatus (1 ) according to claims 2 and 9, wherein the collecting devices (5) of each collecting group (22) are movable with respect to said winding spindle (14) at least when the collecting group (22) is in the loading zone (LZ) to face each collecting device (5) one after the other to a corresponding transfer device (1 1 ).

12. Method for making a coil winding comprising: arranging a plurality of segments of strip-shaped elements (100); winding segments of strip-shaped elements (100) on respective collecting devices (5); checking whether the segments of strip-shaped elements (100) wound or to be wound on the collecting devices (5) have any defects and; if all the segments of strip-shaped elements (100) checked do not have defects, unwinding the segments of strip-shaped elements (100) from the collecting devices (5) and feeding them towards a winding spindleif at least one segment of strip-shaped element (100) checked has defects, not unwinding the segments of strip-shaped elements (100) from the collecting devices (5) to feed them towards the winding spindle (14) and unwinding only the segment of strip-shaped element (100) that has defects from the respective collecting device (5) to reject it.

13. Method according to claim 12, wherein when a segment of defective stripshaped element (100) has been unwound from the respective collecting device (5) and rejected, it is provided to wind a new segment of strip-shaped element (100) only on the collecting device (5) from which the defective strip-shaped element (100) was unwound and rejected.

14. Method according to claim 13, comprising checking whether the new segment of strip-shaped element (100) has any defects and: if the new segment of strip-shaped element (100) wound or to be wound on the collecting device (5) has no defects, it is provided to unwind the segments of strip-shaped elements (100) from the collecting devices (5) and feed them towards the winding spindle (14); if the new strip-shaped element segment (100) wound or to be wound on the collecting device (5) has defects, it is provided not to unwind the segments of strip-shaped elements (100) from the collecting devices (5) to feed them towards the winding spindle (14) and to unwind only the new strip-shaped element segment (100) that has defects from the respective collecting device (5) to reject it.

15. Method according to any one of claims 12 to 14, comprising arranging at least one collecting group (22) comprising at least two collecting devices (5) and a winding spindle (14).

16. Method according to claim 15, wherein if all the segments of strip-shaped elements (100) wound on the collecting devices (15) of said at least one collecting group (22) have no defects, it is provided to unwind all the segments of stripshaped elements (100) from the respective collecting devices (5) of said at least one collecting group (22) and feed them towards the winding spindle (14).

17. Method according to claim 15 or 16, wherein if at least one segment of stripshaped element (100) wound on any collecting device (5) of said at least one collecting group (22) has defects, it is provided not to unwind any segment ofstrip-shaped element (100) from the respective collecting device (5) of said at least one collecting group (22) towards the winding spindle (14) and to unwind the only defective segment of strip-shaped element (100) from the collecting device (5) and reject it.

18. Method according to claim 17, wherein when a segment of defective stripshaped element (100) has been unwound from the respective collecting device (5) and rejected, it is provided to wind a new segment of strip-shaped element (100) only on the collecting device (5) from which the defective strip-shaped element (100) was unwound and rejected.

19. Method according to any one of claims 12 to 18, wherein checking whether a segment of strip-shaped element (100) has any defects precedes winding said segment of strip-shaped element (100) on a respective collecting device (5).

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