Apparatus and method for making coils, preferably for making coils for electrochemical cells intended for battery production - Patents.com

Abstract

The apparatus (100) for making a coil (B) comprises a supply unit (2) configured to supply at least one strip-like article (N) formed by a plurality of strips (N1, N2, N3, N4) and a winding unit (1). The winding unit (1) comprises a plurality of winding heads (10) and a winding head movement device (3) configured to displace the winding head (10) along a working path (P). The apparatus comprises a storage device (4) configured to store a variable amount of at least one strip (N1, N2, N3, N4) and an actuation device for the storage device (4) for displacing the storage device (4) to vary the amount of the stored strip.

Description

[Technical field]

[0001] The present invention relates to an apparatus for making coils, for example of the type formed from a strip or a strip-like article comprising a plurality of overlapping strips.

[0002] Furthermore, the present invention relates to a method for making such a coil.

[0003] The invention finds application preferably in the technical field of the production of electrochemical cells, the realization of which, although not exclusively, involves the winding of strip-like articles. [Background technology]

[0004] In particular, it is known in the relevant art to combine conductor and separator strips in layers to form anode and cathode structures, the resulting article being subsequently wound into a coil and used to construct the electrochemical cell itself.

[0005] WO2010023525A1 describes an example of an apparatus and method for making a battery by winding conductor and separator strips.

[0006] In this specification and the appended claims, certain terms and phrases, unless expressly stated to the contrary, are intended to have the meanings set forth in the following definitions.

[0007] The term "strip-like moulding" is intended to mean any solid product that is presented in an industrial production line in the form of an elongated strip or ribbon, i.e. in the form of an element whose longitudinal extension is significantly greater than its lateral extension. Strip-like articles can be formed by a single strip or ribbon of material or by superimposing several strips arranged in layers.

[0008] Also, the strip-like article has properties that allow for some bending during its progression along the relative production line.

[0009] Strip-like articles can be made, for example, by stacking alternating conductor and insulating layers, which are intended to form a sandwich that is wound to make a coil for the production of an electrochemical cell.

[0010] The term "winding" is intended to mean the creation of a helical structure by rotating a strip, ribbon, or more generally a strip-like article around an axis, flat surface, or other structure. By winding, the strip-like article forms one or more revolutions around the axis or structure.

[0011] The term "coil" is intended to mean any helical structure formed by winding a strip, ribbon, or more generally a strip-like article about an axis, flat surface, or another winding structure. Depending on the structure about which the strip-like article is wound, the overall shape of the coil may be substantially cylindrical, as opposed to being flattened or otherwise.

[0012] As mentioned above, coils have applications not only in the technical field of electrochemical cells, but also in other technical fields, such as, for example, in the field of conductors, in which coil-like structures can be used as well.

[0013] The term "closed path" is intended to mean a path traveled by a winding head or other element, the start and end points of which are substantially coincident.

[0014] The term "continuous" is a term used to describe motion and refers to an uninterrupted motion without any halt or interruption in the motion of the object. In particular, with respect to the movement of a strip or other element, the term "continuous" indicates that the strip does not stop during its movement.

[0015] The term "substantially constant" as it relates to a measurement or quantity, such as the displacement velocity of an object, means that such measurement or quantity maintains a value over time that preferably varies by no more than ±10%, preferably no more than ±5%, preferably no more than ±2%.

[0016] The term "integral" referring to the movement of two or more elements means that these elements perform substantially the same movement substantially simultaneously. In other words, two integral elements are not necessarily joined or connected to each other, but move together as a single body. In fact, it may be provided that the respective motion systems of the two elements are adjusted to move the two elements together as required. Furthermore, it is also possible to use temporary constraints between the two elements, which make it possible, for example, to connect them to each other in several steps, move them together, separate them again and move them independently of each other.

[0017] Also, note that the phrase "displacing an object between a first position and a second position" refers to both displacement from the first position to the second position and displacement from the second position to the first position.

[0018] This definition applies equally to similar expressions of motion, such as the transport or movement of a general object between two locations, between two regions, or between two different motion configurations. Summary of the Invention [Problem to be solved by the invention]

[0019] The applicant has preliminarily observed that, in the context of the constant need to improve the performance and efficiency of production processes, in a production line for making coils, the feed rate of the strip-like article to the unit that carries out the winding can be an important factor limiting the production capacity of the line itself.

[0020] Moreover, this limitation becomes even more important when high precision is required in the formation of the coils. In particular, the Applicant has noted that in many applications, such as the production of electrochemical cells, high precision in the geometry of the windings must be ensured in order to ensure the required performance of the final product.

[0021] This requirement entails a total slowdown of the production line, since the advancement of the strip-like article must be interrupted in order to ensure the required winding accuracy.

[0022] However, the applicant has observed that this solution leads to the creation of tension conditions on the strip-like article due to its stopping and / or restarting, the occurrence of which can impair the production quality of the final product obtained through the coil formed by winding the article.

[0023] The applicant has therefore realised that in order to improve the running speed of a coil using a strip-like article, this can be achieved by operating in addition to the strip-like article a winding head which serves to wind it.

[0024] Applicant has also noted that by using two or more winding heads, it is possible to perform actions on two or more different coils simultaneously and / or to move one of the winding heads along a reset path while the other winding head performs processing.

[0025] The applicant has therefore further realized that it is possible to increase the manufacturing speed of the coils compared to known solutions if the movement of the strip is not interrupted between the different operating steps of the process in which the apparatus operates.

[0026] Finally, the Applicant has discovered that it is possible to avoid interruptions in the advancement of the strip by providing the possibility of storing an appropriate amount of the strip in a particular step, after which the strip thus stored can be retrieved in a later step.

[0027] These features allow the strip to advance continuously, thereby increasing the winding speed of the strip and avoiding tension conditions in the strip while eliminating the need to stop the strip during such operation. [Means for solving the problem]

[0028] Thus, in a first aspect thereof, the present invention relates to an apparatus for making coils for electrochemical cells, preferably intended for the production of batteries.

[0029] Preferably, the apparatus comprises a supply unit configured to supply at least one strip-like article, preferably comprising one or more strips including a conductor strip and a separator strip.

[0030] The supply unit preferably comprises an outlet portion through which the strip-like goods are supplied to the winding unit, and preferably an inlet portion.

[0031] Preferably, the inlet portion is adapted to receive at least one strip from a respective delivery device.

[0032] Preferably, the apparatus comprises a winding unit.

[0033] Preferably, the winding unit comprises a plurality of winding heads, each of the winding heads being configured to wind the strip-like article to form a coil.

[0034] Preferably, the winding unit comprises a movement device for moving the winding head, configured to displace the winding head along the working path.

[0035] Preferably, the apparatus comprises a storage device, preferably between the inlet and outlet portions, configured to store a variable amount of at least one strip.

[0036] Preferably, the apparatus comprises a device for actuating the storage device, which preferably displaces the storage device to vary the amount of strips stored.

[0037] These properties make it possible to envisage a step in which at least one of the strips continues to advance but is not fed to the winding head and in particular is not wound up, in this way the cutting step can be better controlled and / or in the case of strip-like articles formed by several overlapping layers strips of different lengths can be provided.

[0038] It is also possible, for example, to simultaneously store all the strips forming the strip-like article when the moving device, and thus the movable part, moves along the working segment, and to utilize the amount of stored strip for quickly winding up the thus stored strip and / or for optimally adjusting the tension of the strip.

[0039] In a second aspect thereof, the present invention relates to a method for making a coil for an electrochemical cell, preferably intended for the production of a battery, wherein the coil is made by winding of at least one strip-like article.

[0040] Preferably, the method includes the step of providing a plurality of winding heads movable along the working path.

[0041] Preferably, the method envisages winding of a strip of product by a winding head.

[0042] Preferably, the method includes the step of storing a variable amount of at least one strip in an upstream position relative to the winding head, where the stored amount is preferably variable during displacement of the winding head.

[0043] Based on this aspect, it is possible to achieve the same advantages as described in relation to the previous aspect.

[0044] In a third aspect thereof, the present invention relates to an apparatus for making coils for electrochemical cells, preferably intended for the production of batteries.

[0045] Preferably, the apparatus comprises a supply unit configured to supply at least one strip-shaped article, displacing the strip-shaped article along a supply direction, preferably including one or more strips comprising a conductor strip and a separator strip.

[0046] Preferably, the apparatus comprises a winding unit.

[0047] Preferably, the winding unit includes a plurality of winding heads.

[0048] Preferably, the winding unit comprises a movement device for moving the winding head arranged to displace the winding head along the working path.

[0049] Preferably, each of the winding heads supports a gripping device configured to grip a portion of the strip-like article and is configured to wind the strip-like article to create a coil.

[0050] Preferably, the displacement device is further configured to displace the respective winding head along an active segment of the working path in a direction out of line with the feed direction when gripping a portion of the strip.

[0051] These properties allow the length of the strip-like product to be short or minimized while the strip is being wound, thus limiting the situations that create tension in the strip and generally allowing for faster winding speeds.

[0052] In a fourth aspect thereof, the present invention relates to a method for making a coil for an electrochemical cell, preferably intended for the production of a battery, wherein the coil is made by winding of at least one strip-like article.

[0053] Preferably, the method includes the step of providing a plurality of winding heads movable along the working path.

[0054] Preferably, it is envisaged to move the strip-like product in a feed direction so as to feed it to one of the winding heads.

[0055] Preferably, the method includes the step of gripping a portion of the strip-like product by a gripping device of the winding head.

[0056] Preferably, the method includes the step of displacing the winding head along an active segment of the working path in a direction out of line with the feed direction while gripping a portion of the strip-like article.

[0057] Based on this aspect, it is possible to achieve the same advantages as described in relation to the previous aspect.

[0058] In a fifth aspect thereof, the present invention relates to an apparatus for making coils for electrochemical cells, preferably intended for the production of batteries.

[0059] Preferably, the apparatus comprises a supply unit configured to supply at least one strip-like article, preferably a plurality of strips comprising a conductor strip and a separator strip.

[0060] Preferably, the apparatus includes a winding unit.

[0061] Preferably, the winding unit comprises a plurality of winding heads, each of the winding heads being configured to wind the strip-like article around a respective winding axis to create a coil.

[0062] Preferably, the winding unit comprises a movement device for moving the winding head, configured to displace the winding head along the working path.

[0063] The winding head is displaced according to a trajectory which includes at least one rotation about a rotation axis of the moving device which is preferably different from the winding axis, and a translation and / or rotation about a further axis which is preferably different from the rotation axis and the winding axis.

[0064] These characteristics allow a special movement mechanism to achieve periodic movement of the rotating head obtained by rotation around the rotation axis of the moving device and further movement of the head obtained by translational and / or further rotational movements.

[0065] In this way, with a constructionally simple solution, high speeds can be achieved and the necessary trajectory of the winding head can be obtained in order to carry out the winding of the strip while the head itself is moving, without tension states of the strip and movements that are difficult to control.

[0066] It should be noted that the trajectory traveled by the take-up head may include rotations and translations / rotations in sequence, or may include a compound rotation / translation motion that includes such rotations / translations.

[0067] In a sixth aspect thereof, the present invention relates to a method for making a coil for an electrochemical cell, preferably intended for the production of a battery, wherein the coil is made by winding of at least one strip-like article.

[0068] Preferably, the method includes the step of providing a plurality of winding heads.

[0069] Preferably, it is envisaged that the strip-like article is wound around a winding shaft by one of the winding heads.

[0070] The method includes a step of moving the winding head according to a trajectory formed by at least one rotation about a rotation axis of the moving device, preferably different from the winding axis, and by a translation and / or rotation about a further axis, preferably different from the rotation axis and the winding axis.

[0071] Based on this aspect, it is possible to achieve the same advantages as described in relation to the previous aspect.

[0072] In a seventh aspect thereof, the present invention relates to an apparatus for making coils for electrochemical cells, preferably intended for the production of batteries.

[0073] Preferably, the apparatus comprises a supply unit configured to supply at least one strip-like article, preferably comprising one or more strips including a conductor strip and a separator strip.

[0074] Preferably, the supply unit comprises a movable part which includes an outlet portion through which the strip-like goods pass as they leave the supply unit.

[0075] Preferably, the apparatus comprises a winding unit configured to receive the strip of goods from the outlet portion.

[0076] Preferably, the winding unit includes a plurality of winding heads.

[0077] Preferably, the winding unit comprises a movement device, preferably for moving the winding head.

[0078] Preferably, each of the winding heads is configured to wind a strip-like article to create a coil.

[0079] Preferably, the winding head and the movable part are both movable.

[0080] Preferably, the moving device is configured to move the winding heads along the working path so as to maintain each winding head on which the strip-like article is wound at a predetermined distance from the movable part while the winding heads are moving.

[0081] These properties allow the distance between the feeding unit and the winding head to be controlled at various stages in the production of the coil, providing an appropriate distance for winding to be performed, minimizing tension conditions and allowing cutting of the strip-like article if necessary.

[0082] In an eighth aspect thereof, the present invention relates to a method for making a coil for an electrochemical cell, preferably intended for the production of a battery, wherein the coil is made by winding of at least one strip-like article.

[0083] Preferably, the method includes the step of providing a plurality of winding heads movable along the working path.

[0084] Preferably, the method envisages feeding the strip-like product to one of the winding heads via an outlet portion of the feeding unit.

[0085] Preferably, the method comprises the step of winding the strip of product by a winding head to which the strip of product is supplied.

[0086] It is preferably envisaged that the outlet section and the winding head to which the strip-like goods are supplied are kept at a predetermined distance and moved simultaneously.

[0087] Based on this aspect, it is possible to achieve the same advantages as described in relation to the previous aspect.

[0088] In a ninth aspect thereof, the present invention relates to an apparatus for making coils for electrochemical cells, preferably intended for the production of batteries. Preferably, the apparatus comprises a supply unit configured to supply strip-like articles comprising one or more strips, preferably comprising at least a conductor strip and a separator strip.

[0089] The apparatus comprises a winding unit.

[0090] Preferably, the winding unit comprises a plurality of winding heads, each of which is preferably configured to wind the strip-like article to create a coil.

[0091] Preferably, the winding unit may comprise a movement device for moving the winding head, configured to displace the winding head along the working path.

[0092] Preferably, the plurality of winding heads comprises at least a first winding head and a second winding head.

[0093] Preferably, the movement device is configured to vary the distance between the first winding head and the second winding head along the working path.

[0094] These properties make it possible, in particular due to the possibility of varying the distance between the two winding heads, to efficiently manage the step of making the coil, in particular by varying the distance between the two heads between the step in which winding takes place and the step in which the strip-like product is cut.

[0095] In a tenth aspect thereof, the present invention relates to a method for making a coil for an electrochemical cell, preferably intended for the production of a battery, wherein the coil is made by winding of at least one strip-like article.

[0096] Preferably, the method includes the step of providing a plurality of winding heads movable along the working path.

[0097] Preferably, the plurality of winding heads comprises at least a first winding head and a second winding head.

[0098] Preferably, the method comprises the step of winding the strip-like product by a first winding head and / or a second winding head.

[0099] It is also preferably envisaged to vary the distance between the first and second winding heads along the working path.

[0100] Based on this aspect, it is possible to achieve the same advantages as described in relation to the previous aspect.

[0101] In an eleventh aspect thereof, the present invention relates to an apparatus for making coils for electrochemical cells, preferably intended for the production of batteries.

[0102] Preferably, the apparatus comprises a supply unit configured to supply at least one strip-like article, preferably comprising one or more strips including a conductor strip and a separator strip.

[0103] Preferably, the apparatus comprises a winding unit.

[0104] Preferably, the winding unit includes a plurality of winding heads.

[0105] Preferably, the winding unit comprises a movement device for moving the winding head, which is configured to displace the winding head along the working path.

[0106] Preferably, each of the winding heads is configured to wind a strip-like article to create a coil.

[0107] Preferably, the winding heads are movable along the working path, preferably at least in the segment defined between the supply unit and said winding heads, so that at least one strip-like article is subjected to a substantially constant tension as a result of the movement of the winding head during winding of the strip-like article by the respective winding head.

[0108] The expression "substantially constant tension" means that the tension remains constant during the operating steps of the device, preferably with a variation of not more than ±10%, preferably not more than ±5%. Furthermore, in the context of the present invention, a constant or substantially constant state of tension can preferably be indicated by a constant or substantially constant speed of the strip-like article during the steps of feeding and winding the strip.

[0109] These properties make it possible to provide the strip-like article with a substantially constant tension, in particular while the coil is being made, due to the fact that the winding takes place whilst the winding head is displaced.

[0110] These properties make it possible to provide the strip-like article with a substantially constant tension, in particular while the coil is being made, due to the fact that the winding takes place whilst the winding head is displaced.

[0111] In this way, the productivity of the device can be increased in terms of the number of windings per unit time, and the winding characteristics can be improved, resulting in more accurate and regular winding.

[0112] In a twelfth aspect thereof, the present invention relates to a method for making a coil for an electrochemical cell, preferably intended for the production of a battery, wherein the coil is made by winding of at least one strip-like article.

[0113] Preferably, the method includes the step of providing a plurality of winding heads movable along the working path.

[0114] Preferably, the method envisages winding of the strip-like product by multiple winding heads.

[0115] Preferably, the method includes the step of moving a winding head on which the strip-like product is wound such that the strip-like product is subjected to a substantially constant tension.

[0116] Based on this aspect, it is possible to achieve the same advantages as described in relation to the previous aspect.

[0117] In a thirteenth aspect thereof, the present invention relates to an apparatus for making coils for electrochemical cells, preferably intended for the production of batteries.

[0118] Preferably, the apparatus comprises a supply unit configured to supply at least one strip-like article, preferably formed by a plurality of strips including conductor strips and separator strips.

[0119] Preferably, the apparatus comprises a winding unit.

[0120] Preferably, the winding unit includes a plurality of winding heads.

[0121] Preferably, the winding unit comprises a movement device for moving the winding head, configured to displace the winding head along the working path.

[0122] Preferably, each of the winding heads is configured to wind a strip-like article to create a coil.

[0123] Preferably, the at least one strip is continuously supplied to the winding head by a supply unit.

[0124] These properties allow the coils to be made without interrupting the supply of strip, thus avoiding interruptions in the strip movement that could create undesirable tension conditions and reduce the productivity of the machine, which is always beneficial for productivity and the quality of the product made.

[0125] In a fourteenth aspect thereof, the present invention relates to a method for making a coil for an electrochemical cell, preferably intended for the production of a battery, wherein the coil is made by winding of at least one strip-like article.

[0126] Preferably, the method includes combining a plurality of layers, preferably including conductor strips and separator strips, to form a strip-like article.

[0127] Preferably, the at least one strip is supplied continuously.

[0128] Preferably, the method includes the step of providing a plurality of winding heads movable along the working path.

[0129] Preferably, the method includes the step of providing a plurality of winding heads movable along the working path.

[0130] Based on this aspect, it is possible to achieve the same advantages as described in relation to the previous aspect.

[0131] In a fifteenth aspect thereof, the present invention relates to an apparatus for producing coils for electrochemical cells, preferably intended for the production of batteries, the apparatus preferably comprising a supply unit adapted to supply at least one strip-like article comprising one or more strips, preferably including a conductor strip and a separator strip.

[0132] Preferably, the apparatus comprises a winding unit including a plurality of winding heads.

[0133] Preferably, the apparatus comprises a movement device for moving the winding head, which is preferably configured to displace the winding head along the working path.

[0134] Preferably, each of the winding heads is configured to wind the strip during displacement of the winding head by the movement device along the working segment of the working path to create the coil.

[0135] These properties allow the machine for making the coils to wind the strip-like product without the need to interrupt the supply, as the winding head can move while the strip-like product is being wound.

[0136] In this way, it is possible to control the tension acting on the strip-like product by acting on the winding speed and on the movement of the winding head, making it possible to operate at higher speeds than known solutions and at the same time guaranteeing the required quality of the coil construction.

[0137] In its sixteenth aspect, the present invention relates to a method for making a coil for an electrochemical cell, preferably intended for the production of a battery, wherein the coil is made by winding of at least one strip-like article.

[0138] Preferably, the method includes the step of providing a plurality of winding heads movable along the working path.

[0139] Furthermore, the method preferably includes the step of winding the strip-like article by the winding head during displacement of the winding head along the working segment of the working path.

[0140] The method according to this aspect allows the coil to be made faster than in known solutions and without interruptions in the path of the strip-like article, due to the possibility of carrying out the winding while the winding head itself is moving along the working path, in particular along certain segments thereof: the displacement of the winding head can in fact be made to supply and regulate the strip-like article to the winding head in such a way that during the coil making process it is not necessary to interrupt the advancement of the strip-like article or the corresponding strip which forms it.

[0141] In a seventeenth aspect thereof, the present invention relates to an apparatus for making coils for electrochemical cells, preferably intended for the production of batteries.

[0142] Preferably, the apparatus comprises a supply unit configured to supply at least one strip-like article, preferably comprising one or more strips including a conductor strip and a separator strip.

[0143] Preferably, the apparatus comprises a winding unit including a plurality of winding heads.

[0144] Preferably, each of the winding heads supports a gripping device configured to grip a portion of the strip-like product.

[0145] Preferably, the winding unit comprises a movement device for moving the winding head arranged to displace the winding head along the working path.

[0146] Preferably, each of the winding heads is configured to wind a strip-like article to create a coil.

[0147] Preferably, each of the gripping devices comprises a pair of pins configured to hold the strip-like article therebetween.

[0148] Preferably at least one of the pins is moveable to engage with the other pin holding the strip of goods therebetween.

[0149] These properties allow the strip-like goods to be gripped and blocked for winding in a simple manner as part of a continuous and automated process.

[0150] In an eighteenth aspect the present invention relates to a method for making a coil for an electrochemical cell, preferably intended for the production of a battery, wherein the coil is made by winding of at least one strip-like article.

[0151] Preferably, the method includes the step of providing a plurality of winding heads movable along the working path.

[0152] Preferably, the method includes the step of gripping a portion of the strip-like product by a winding head.

[0153] Preferably, winding of a strip-like product by a winding head is envisaged.

[0154] Preferably, the step of gripping a portion of the strip-like article comprises the step of placing the portion of the strip-like article between a pair of pins, at least one of which is moveable to engage with the other pin holding the strip-like article between them.

[0155] Based on this aspect, it is possible to achieve the same advantages as described in relation to the previous aspect.

[0156] In a nineteenth aspect thereof, the present invention relates to an apparatus for making coils for electrochemical cells, preferably intended for the production of batteries.

[0157] Preferably, the apparatus comprises a supply unit configured to supply at least one strip-like article formed by a plurality of strips, preferably including conductor strips and separator strips.

[0158] Preferably, the supply unit comprises a movable part.

[0159] Preferably, a respective feed path is defined for each strip.

[0160] Preferably, the supply paths comprise respective storage segments, the storage segments being preferably substantially parallel to each other.

[0161] Preferably, the apparatus comprises a winding unit including at least one winding head configured to wind the strip-like article to create a coil.

[0162] Preferably, the supply unit is configured to vary the longitudinal extension of each of the storage segments by moving the movable part, the longitudinal extensions of the storage segments being varied simultaneously, preferably by the same amount, preferably while the storage segments are maintained substantially parallel to one another.

[0163] These properties allow the displacement of the moving part to be used to simultaneously store the same amount of strip for each of the strips forming the strip-like product, thus allowing a continuous supply of strip to be used while also providing stages in which the strip-like product is not wound up.

[0164] In its twentieth aspect, the present invention relates to a method for making a coil for an electrochemical cell, preferably intended for the production of a battery, preferably wherein the coil is made by winding of at least one strip-like article.

[0165] Preferably, the method includes the step of advancing a plurality of strips along respective feed paths, where the plurality of strips preferably includes conductor strips and separator strips.

[0166] Preferably, at the end of the feed path, it is envisaged that the strips are combined in layers to form a strip-like article.

[0167] Preferably, the method comprises the steps of providing at least one winding head and preferably winding the strip-like article by the winding head.

[0168] Preferably, each of the supply paths comprises a storage segment having a variable length, the storage segments being preferably substantially parallel to each other.

[0169] Preferably, the method includes changing the length of each of the storage segments simultaneously, preferably by the same amount, and preferably the storage segments are maintained substantially parallel to one another while changing the lengths.

[0170] Based on this aspect, it is possible to achieve the same advantages as described in relation to the previous aspect.

[0171] The present invention, in at least one of the above-mentioned aspects, may have at least one of the further preferred features described below.

[0172] Preferably, each of the winding heads supports a gripping device configured to grip a portion of the strip-like product, the gripping device further preferably being configured to rotate on itself about the winding axis so as to wind the strip-like product.

[0173] This feature allows the strip-like article to be easily gripped and wound by rotating the same device that grips the article, thus allowing easy control of the rotation speed while winding the strip-like article, as well as the trajectory and speed of the winding head.

[0174] Preferably, the supply unit defines a supply direction of the strip-like articles.

[0175] In this way, the supply unit itself defines the direction in which the strip-like article is supplied, ie the direction in which it reaches the winding head and is then gripped and wound up.

[0176] If the strip-like article is formed by a number of strips, the feed direction coincides with the feed direction of the article after the strips have been combined between them.

[0177] Preferably, the movement device is configured to wind the strip-like article during displacement of the winding head. Preferably, the displacement of the respective winding head during winding is in a direction opposite to the feed direction.

[0178] This characteristic allows the length of the strip-like article to be kept short or at a minimum while the strip is being wound, thus limiting the situations that create tension conditions in the strip and generally allowing higher winding speeds to be achieved.

[0179] It should be noted that when the term "mismatch" and its antonym "agreement" refer to two directions, these directions are understood to be directed in opposite directions for mismatch and in the same direction for agreement.

[0180] These directions do not necessarily have to be parallel; in this case, two directions are considered to be incongruent if the component of one direction that is parallel to the second direction defines a path along which an object is displaced in the opposite direction relative to the other direction.

[0181] This concept is shown diagrammatically in Figure 11, where the two directions are indicated by solid lines and are designated by the references a and b, and the component parallel to the second direction is indicated by a dotted line and is designated by the reference c. In the example shown, the two directions are represented as being incongruent, as can be seen from the arrows present on the two lines.

[0182] Preferably, the displacement of the winding head of each working segment is substantially parallel to the feed direction.

[0183] In the context of the present invention, the term "substantially parallel" indicates a possibility of deviation from perfect parallelism of ±10°, preferably ±5°.

[0184] This characteristic allows the winding head to follow the forward motion of the strip and / or move in a direction opposite to the advance of the strip to wind the strip in such a manner, each of which further contributes to making the winding of the strip, and thus the formation of the coil, faster and more efficient.

[0185] Preferably, the supply unit comprises an outlet portion through which the strip-like articles pass as they leave the supply unit and are supplied to the winding unit, and an inlet portion preferably adapted to receive at least one strip from a respective delivery device, and a supply path for the strips is provided between the inlet portion and the outlet portion.

[0186] Preferably, the supply unit comprises a movable part in which the outlet portion is preferably formed.

[0187] The presence of a movable part in the supply unit makes it possible to vary the position of the exit of the strip of goods fed to the winding head, in this way the winding head can grip the strip of goods more easily and also adjust the distance between the head and the supply unit and thus the length of the strip between the head and the supply unit where the strip of goods is wound.

[0188] Preferably, the apparatus comprises a cutting device configured to cut the strip-like product at a position downstream of the supply unit.

[0189] The presence of the cutting device downstream of the supply unit makes it possible to avoid the need to stop the strip at the moment it is cut, and makes it possible to couple the cutting action with the movement of the head, which is achieved via a relative movement device.

[0190] Preferably, the supply unit and the moving device are configured such that the respective winding head is located at a predetermined distance from the supply unit in preparation for when the cutting device cuts the strip-like product, where the predetermined distance is preferably substantially equal to a minimum distance from the supply head.

[0191] It should be noted that although the term "substantially equal" refers to the shortest distance between the two components, in the context of the present invention, the two components may also be at a slightly smaller distance during different operational steps of the device, but overall, this distance can be considered as the minimum value that can be obtained, to suit the motion mechanisms that move the two components and their overall dimensions.

[0192] In other words, the winding heads may be positioned at distances less than they are positioned at during the cutting steps described above while moving along the working path, but in the context of this operation the distance they are positioned is the minimum distance they can be positioned to allow access and use of the devices used for cutting and to accommodate the motion mechanisms used for movement.

[0193] This characteristic makes it possible to minimize the length of the portion of the strip-like product leaving the supply unit at the moment the cut is made, thus simplifying the management, and in particular the winding operations, of the two portions of the strip-like product resulting from the cut.

[0194] Preferably, the supply unit and the moving device are configured such that when the cutting device has cut the strip-like product, the respective winding head is located at a minimum distance from the movable part.

[0195] Based on this characteristic, the movement of the movable part can be advantageously utilized to achieve the above-mentioned arrangement of the winding head over the shortest possible distance.

[0196] Preferably, the cutting device is moveable together with the winding head and / or the strip-like article.

[0197] Preferably, the movement device is configured to displace the winding head along the working path according to a trajectory which includes at least the following: Rotation about the axis of rotation of the moving device, where the axis of rotation is different from the axis of winding. · Translation and / or rotation about further axes different from the axis of rotation and the axis of winding.

[0198] This property allows a special movement mechanism to achieve periodic movement of the rotating head obtained by rotation around the rotation axis of the moving device and further movement of the head obtained by translational and / or further rotational movements.

[0199] In this way, with a constructionally simple solution, high speeds can be achieved and the necessary trajectory of the winding head can be obtained in order to carry out the winding of the strip while the head itself is moving, without tension states of the strip and movements that are difficult to control.

[0200] Preferably, the movement device is configured to cause the winding heads to perform a combination of the following movements: translations that do not change the distance between the heads, and / or any combination of movements that change the distance between the heads.

[0201] Preferably, the winding head and the movable part are movable in a coordinated manner, and the moving device is configured to move the winding head along the working segment so as to maintain each winding head from which the strip-like article is wound at a predetermined distance from the movable part while the winding head is moving.

[0202] These properties allow the distance between the feeding unit and the winding head to be controlled at various stages in the production of the coil, providing an appropriate distance for winding to be performed, minimizing tension conditions and allowing cutting of the strip-like article if necessary.

[0203] Preferably, the at least one strip-like article is subjected to a substantially constant tension at least along the segment between the supply unit and the respective winding head around which the strip-like article is wound.

[0204] Preferably, the at least one strip-like article is subjected to a substantially constant tension, at least for the segment provided between the supply unit and the respective winding head around which the strip-like article is wound.

[0205] Preferably, the supply unit is configured to supply the strip-like article at a supply speed and the winding head is configured to wind the strip at a winding speed and to displace it at a displacement speed, the winding speed and the displacement speed being preferably such as to provide a substantially constant tension in the strip-like article.

[0206] In this way, it is possible to control the tension simply by controlling the speed at which the device is operated, and as a result, the operating steps of the device can be easily controlled.

[0207] Preferably, the feed speed is substantially equal to the sum of the take-up speed and the displacement speed.

[0208] This condition allows a substantially constant tension to be maintained in the strip-like article without the need to stop it during winding or coiling.

[0209] Preferably, the strip-like article comprises a plurality of overlapping strips in a layered manner, at least one strip being supplied continuously.

[0210] Preferably, the feed rate is always greater than zero along the feed path, and is preferably substantially constant.

[0211] These properties allow coils to be made without interrupting the supply of strip, thus avoiding interruptions in strip movement that could create undesirable tension conditions and reduce the productivity of the machine.

[0212] Preferably, the supply unit comprises a coupling roller, the strip being arranged to converge towards the coupling roller where the strip is partially wound so that downstream of the coupling roller the strip is grouped to form a strip-like article.

[0213] Preferably, the outlet portion is defined in the coupling roller.

[0214] Preferably, the coupling roller is connected to the movable part.

[0215] These properties make it possible to group the strips in order to obtain a multi-layer strip-like article with a solution that allows a continuous advancement of the strips. Moreover, the position at which the strips are joined can be advantageously varied during the different operating steps of the device.

[0216] Preferably, the working segment comprises at least a first portion and a second portion which are preferably substantially parallel to each other.

[0217] This characteristic makes it possible to use a non-overly complex movement mechanism for moving two substantially parallel segments, thus allowing to obtain working segments with a wide range of extension and to use a relatively simple movement device from a construction point of view.

[0218] Preferably, the movement device is configured to displace each of the winding heads in a first direction along the first portion and in a direction opposite to the first direction along the second portion.

[0219] In this way, the overall dimensions of the transfer device, and more generally of the apparatus, can be optimized, since the winding head can move in two directions opposite to each other along two substantially parallel segments.

[0220] Preferably, each of the gripping devices is configured to wind the strip of article along the first portion at a different speed than along the second portion.

[0221] The use of different winding speeds allows maintaining a substantially constant tension in the strip of product during winding, especially if it is continuously fed.

[0222] Preferably, the winding head is displaced in a direction consistent with the feed direction in the first portion and in a direction not consistent with the feed direction in the second portion, and the winding heads are preferably configured to wind the strip-like article at a faster speed when each winding head is displaced in a direction not consistent with the feed direction.

[0223] These characteristics make it possible to optimally utilize the movement of the winding head in order to wind the strip-like product as quickly as possible, taking into account the fact that during winding the winding head moves and at the same time the strip-like product continues to be supplied.

[0224] Preferably, the working segment comprises a third portion, preferably substantially parallel to the first portion and / or the second portion, along which the winding head is displaced again in a direction coinciding with the feed direction.

[0225] The presence of the third part makes it possible to further exploit the properties of the moving device in a cyclical solution, preferably displacing the winding head along a closed path.

[0226] Preferably, the strip-like article is wound up during displacement of the moving head along the first portion and / or the second portion and / or the third portion.

[0227] Preferably, the moving device is configured to wind the strip-like article by an amount between 5% and 15%, preferably 10%, of the total length of the strip-like article used to form the single coil along the first portion. Preferably, the moving device is configured to wind the strip-like article by an amount between 70% and 90%, preferably 80%, of the total length of the strip-like article used to form the single coil along the second portion. Preferably, the moving device is configured to wind the strip-like article by an amount between 5% and 15%, preferably 10%, of the total length of the strip-like article used to form the single coil along the third portion.

[0228] In this way, winding takes place mainly during the return movement of the winding head, i.e. along the second portion, and winding can take place at a higher speed as the winding head moves in a direction opposite to the feed direction.

[0229] Preferably, the apparatus comprises a storage device configured to store an amount of at least one strip of the plurality of strips between the inlet portion and the outlet portion, and a device for actuating the storage device, preferably displacing the storage device to vary the amount of stored strip.

[0230] This feature makes it possible to provide a step in which at least one of the strips continues to advance but is not presented to the winding head and in particular is not wound up, in this way the cutting step can be better controlled and / or in the case of a strip-like article formed by several overlapping layers, strips of different lengths can be provided.

[0231] Preferably, the storage device comprises at least one movable element, the movable element being configured to vary the overall length of the feed path by moving the movable element.

[0232] Preferably, the movable element is formed by a movable part.

[0233] Preferably, the movement device is configured to move integrally with the movable part, and is preferably rotatably supported on the movable part.

[0234] In this way, for example, all strips forming a strip-like article can be stored simultaneously when the moving device, and thus the movable part, moves along a first part of the working segment, and the strips thus stored can be rapidly wound up when returning to the second part of the working segment.

[0235] Preferably, the movable element comprises at least one movable roller, and the at least one strip is wound onto the movable roller and onto the at least one fixed roller so as to vary the overall length. Preferably, the movable roller and the fixed roller are configured to run idle.

[0236] This feature allows the advancement of a single strip, or of a particular strip, to be offset with respect to the remaining strips, without the need to stop the advancement of the strip, when the strip-like article is formed by several overlapping strips. In this way, by cutting the contained strip at a predetermined position, it is possible to obtain a portion of the strip-like article in which one or more strips forming the multi-layer structure are absent. This is particularly advantageous in the case of coils for electrochemical cells, where it is typically envisaged that the end portions of the coil are only partially filled with separator strips.

[0237] Preferably, the feeding unit comprises a device for holding at least one of the one or more strips, which is configured to slow down or stop the feeding of the at least one of the one or more strips through the outlet portion.

[0238] Preferably, the storage device is configured to store the strip when the holding device slows down or stops feeding of the strip.

[0239] In this way, the storage device can operate when the strip is slowing down or stopped, thereby avoiding tension in the strip, which allows a single strip to be advanced continuously without being fed through the outlet portion of the supply unit.

[0240] Preferably, the working segments include at least one substantially straight segment.

[0241] The presence of a straight segment along which the winding takes place is particularly advantageous in order to avoid undesirable tension conditions on the strip-like product.

[0242] Preferably, the straight segments are substantially parallel to the feed direction, further contributing to keeping the strip-like article free of tension while the coil is being made.

[0243] Preferably, the first portion and / or the second portion and / or the third portion form respective linear segments.

[0244] Preferably, the winding heads are configured to discharge the coil after at least partially winding at least one strip, and the working path includes a reset segment along which each of the winding heads is displaced from a discharge position to a gripping position in which the winding head grips at least one portion of the strip-like article. Preferably, the working path is closed.

[0245] In this manner, the apparatus can operate cyclically and advantageously provide a working segment where the winding head performs the winding, generally creating a coil, and a reset segment where the head can return to the appropriate position to restart the cycle.

[0246] This is particularly advantageous when there is a linear path, or in any case when one wants to concentrate the winding action in a particular area, since it is sufficient to control the rotation of the head and its behavior in this area relative to the strip-like article, thus simplifying the required movement mechanism.

[0247] Preferably, the working segment has a length equal to at least 5%, preferably at least 10%, preferably at least 15%, preferably at least 20% of the overall length of the working path.

[0248] Preferably, in such a working segment, the winding of the strip-like product takes place during each displacement of the winding head during which the strip-like product is wound.

[0249] In other words, such a displacement will therefore cover a significant part of the overall working path of the winding head. It should therefore be noted that the movement of the winding head is not limited to compensating for diameter differences occurring during winding or to compensating for minimal displacements of the strip-like article relative to the moving feed direction during winding.

[0250] In this way, the head can follow the advancement of the strip-like article during its movement and the formation of the coil, which in turn allows for proper utilization of the working segments along which the winding heads move to wind the strip-like article, for example allowing proper coordination of the operation of two or more winding heads by envisaging that a particular head will start winding one coil and another head will finish winding another coil.

[0251] Preferably, the cutting device is configured to cut the strip-like article along an active segment of the working path, preferably in an intermediate region of the working path.

[0252] This feature allows the movement of the winding head to be utilized in various steps, both for winding, cutting and transporting the cut coil to a discharge area.

[0253] Preferably, the plurality of winding heads comprises at least a first winding head and a second winding head, and the movement device is configured to vary the distance between the first winding head and the second winding head along the working path.

[0254] Since the distance between the two winding heads can be varied, the coil production step can be efficiently managed, in particular by varying the distance between the two heads between the step where winding takes place and the step where the strip-like product is cut.

[0255] Preferably, the moving device is configured to move the first winding head closer to the second winding head along the working path as the cutting device cuts the strip-like article.

[0256] In this way, the cut can be performed between two winding heads, minimizing the dimensions of the two flaps of the strip-like product resulting after the cut, where one head is as close as possible to the other head.

[0257] Preferably, the moving device is configured to move the first winding head away from the supply unit and is further configured to displace the second winding head along the actuation segment to an intermediate position between the first winding head and the supply unit when the first winding head is moved away.

[0258] This feature allows the second winding head to be positioned so that it grips the strip-like product while the other winding head is still winding, or in any case gripping, the strip-like product itself, so that this strip-like product is still being wound on the first winding head when the second winding head grips it.

[0259] Preferably, the moving device is configured such that when the first winding head moves along the third portion, a second winding head preceding the first winding head along the working path moves along the first portion.

[0260] This property allows the overall dimensions of the device to be optimized and at least partially allows the winding of two coils to be performed simultaneously, where, after cutting the strip-like article, the first winding head finishes winding the remaining flaps along the third portion and the second winding head starts winding along the first portion.

[0261] Preferably, each of the gripping devices comprises a pair of pins configured to hold a strip-like article between them, at least one of the pins being movable to join with the other pin which holds the strip-like article between them.

[0262] The presence of the pins makes it possible in a simple manner to grip and block the strip-like goods for winding as part of a continuous and automated process.

[0263] Preferably, the winding axis is aligned with the longitudinal extension of the pin.

[0264] Preferably, at least one of the pins is movable along an extraction direction that is transverse, preferably perpendicular, to the feed direction of the strip-like product.

[0265] In this way, one pin approaches the strip during head movement, and the other pin is moved to the other pin's position after reaching the strip, so that the strip-like article can be placed in a sandwich-like configuration between the two pins while the winding head approaches the article. Once in this position, the pin can begin to rotate about itself and begin winding and gripping the strip.

[0266] Preferably, both pins are movable, the pins are configured to be movable independently of each other and movable relative to each other, and both pins are configured to move along the extraction direction.

[0267] In this way the same pin can be advantageously used to grip the strip-like article to begin winding, and to eject the coil once wound.

[0268] Preferably, the displacement direction of the mobile part forms an angle of 30° to 60°, preferably 40° to 50°, with the horizontal. This angle is preferably substantially equal to 45°. In this way, an optimal compromise can be obtained between the overall dimensions related to the stroke of the mobile part and the power required for the vertical movement of the mobile part and all the components supported by it.

[0269] Preferably, each of the strips defines a respective feed path, the feed path including a respective storage segment, the storage segments being preferably substantially parallel to one another.

[0270] Preferably, two or more of the group consisting of the at least one storage segment, the feed direction of the strip-like goods, the displacement direction of the movable part and the at least one portion of the working segment are substantially parallel to each other.

[0271] Preferably, the storage segment, the feed direction of the strip-like goods, the displacement direction of the movable part and at least one portion of the working segment are all substantially parallel to each other.

[0272] Preferably, the supply unit is configured to vary the longitudinal extension of each of the storage segments, preferably in cooperation with the movement of the movable part along the displacement direction.

[0273] In this way, even during storage of the strip forming the strip-like article, a constant tension can be maintained, so that movements of the movable parts do not create undesirable tensions in the strip.

[0274] Preferably, one or more storage segments extend between a respective pair of diverter rollers, which are preferably free-wheeling.Preferably, the pair of diverter rollers are supported on a movable part.

[0275] This characteristic allows the strip to slide while being retracted, particularly during movement of the moving part, without creating the undesirable tensions mentioned above.

[0276] Preferably, the longitudinal extensions of the storage segments are changed simultaneously and by the same amount to maintain the storage segments substantially parallel to one another.

[0277] It should be noted that the term "storage segment" in reference to the strip forming the strip-like product, in the context of the present invention, denotes a variable-length portion of the path travelled by the strip, where there is a sliding of the strip associated with a relative advancement. The storage segment may thus form one or more buffers of the strip forming the strip-like product.

[0278] These properties allow the displacement of the moving part to be used to simultaneously store the same amount of strip for each of the strips forming the strip-like product, thus allowing a continuous supply of strip to be used while also providing stages in which the strip-like product is not wound up.

[0279] The step of combining the strips into a layer includes converging the strips downstream of the storage segment towards an outlet portion through which the strip-like articles are fed to the winding head.

[0280] In this way, a space can be defined between one strip and the other, and before the exit portion, for positioning a gripper and knife that can be used to cut one or more strips before they are combined to form a strip-like article.

[0281] Preferably, the strip-like product is gripped by a gripping device and the strip-like product is wound up by rotating the gripping device about a winding axis.

[0282] This feature also allows for easy gripping of the strip-like product and winding it up by rotating the same device that grips the product, thus allowing for easy control of the rotation speed while winding the strip-like product, as well as the trajectory and speed of the winding head.

[0283] Preferably, the step of gripping a portion of the strip-like product comprises the step of feeding the strip-like product, wherein the strip-like product is fed by displacement in a feeding direction.

[0284] In this way, the supply unit itself defines the direction in which the strip-like article is supplied, ie the direction in which it reaches the winding head and is then gripped and wound up.

[0285] Preferably, the strip-like product is wound up during the displacement of the winding head.Preferably, the winding head is displaced in a direction which does not coincide with the feed direction when winding the strip-like product.

[0286] This characteristic also allows the length of the strip-like article to be kept short or at a minimum while the strip is being wound, thus limiting the situations that create tension in the strip and generally allowing higher winding speeds to be achieved.

[0287] In a preferred embodiment it may be envisaged to feed the strip-like goods to the winding head, the strip-like goods being preferably fed via a strip-like goods outlet section.

[0288] Preferably, the outlet portion is movable along a displacement direction, which is preferably substantially parallel to the feed direction.

[0289] Preferably, the outlet portion is movable forwards and backwards along the displacement direction.

[0290] By moving the outlet section, the position from which the strip of material is fed to the winding head can be varied, in this way the winding head can grip the strip of material more easily and the length of the strip of material between the head and the feed unit where it is wound can be adjusted.

[0291] In a preferred embodiment, it may be envisaged to cut the strip-like product at a location downstream of the supply unit.

[0292] By disengaging the cutting device downstream of the supply unit, it is no longer necessary to stop the strip at the moment it is cut, and it is possible to couple the cutting operation with the movement of the head via the relative movement device.

[0293] Preferably, the winding head is positioned at a minimum distance from the outlet portion in preparation for the step of cutting the strip-like product.

[0294] This characteristic also makes it possible to minimize the length of the portion of the strip-like product leaving the supply unit at the moment the cut is made, thus simplifying the management, and in particular the winding operations, of the two portions of the strip-like product resulting from the cut.

[0295] Preferably, the method includes the steps of providing a cutting device for cutting the strip-like article and displacing the cutting device integrally with the movable part and / or the winding head and / or the strip-like article while the strip-like article is being cut.

[0296] In this manner, cuts can be made while the winding head is moving, without stopping the strip, thus allowing a continuous process for making the coils.

[0297] In a preferred embodiment, it may be envisaged to move the winding head according to a trajectory formed at least by: Rotation about the axis of rotation of the moving device, where the axis of rotation is different from the axis of winding. · Translation and / or rotation about further axes different from the axis of rotation and the axis of winding.

[0298] These steps make it possible to achieve high speeds and the required trajectory of the winding head with a constructionally simple solution in order to realize the winding of the strip while the head itself is moving, without tension states and movements that are difficult to control on the strip.

[0299] In a preferred embodiment, it may be envisaged that the outlet section and the winding head to which the strip-like goods are supplied are kept at a predetermined distance and moved simultaneously.

[0300] These properties also allow the distance between the feeding unit and the winding head to be controlled at various stages in the production of the coil, providing an appropriate distance for winding to be performed, minimizing tension conditions and allowing cutting of the strip-like product if necessary.

[0301] Preferably, it can be envisaged to move the outlet section and the winding head simultaneously while the winding head is winding the strip-like product, the strip-like product being gripped and moved by the winding head in such a way that the strip-like product is subjected to a substantially constant tension upstream of the winding head.

[0302] In this way, the fact that the winding takes place whilst the winding head is displaced makes it possible to provide a substantially constant tension in the strip-like article, in particular whilst the coil is being made.

[0303] Preferably, the shaped strip-like article is fed through the outlet section at a feed speed substantially equal to the sum of the winding speed of the strip-like article and the displacement speed of the winding head around which the strip-like article is wound.

[0304] In this way, the tension can be controlled simply by controlling the speed at which the device is actuated, and as a result, the different movement steps can be easily controlled.

[0305] In a preferred embodiment, it may be envisaged to combine a number of layers to form a strip-like article, where at least one strip is fed continuously.

[0306] Preferably, the feed rate is always greater than zero, and is preferably substantially constant.

[0307] These properties also allow coils to be made without interrupting the supply of strip, thus avoiding interruptions in strip movement that could create undesirable tension conditions and reduce the productivity of the machine.

[0308] It is envisaged that the strips are preferably joined to form a strip-like article by partially wrapping the strips around a coupling roller.

[0309] Preferably, the outlet portion is defined in the coupling roller.

[0310] These properties also make it possible to group the strips in order to obtain a multi-layer strip-like article with a solution that allows a continuous advancement of the strips. Moreover, the position at which the strips are joined can be advantageously varied during the different operating steps of the device.

[0311] In a preferred embodiment, it may be envisaged to move the winding heads substantially parallel to one another along the first and second portions of the working segment, where each of the winding heads is displaced in a first direction along the first portion and in a direction opposite to the first direction in the second portion.

[0312] In this way, it is possible to use a non-overly complex movement mechanism for moving two substantially parallel segments, so that working segments with a wide range of extension can be obtained and movement devices that are relatively simple from a construction point of view can be used.

[0313] Furthermore, since the winding head can move along two substantially parallel segments in two directions opposite to each other, the operating steps of the moving device and, more generally, the method according to the invention can be optimized.

[0314] Preferably, each of the gripping devices is configured to wind the strip of article along the first portion at a different speed than along the second portion.

[0315] Preferably, the winding head is displaced in a direction coinciding with the feed direction in the first portion and in a direction not coinciding with the feed direction in the second portion.

[0316] The strip-like article is preferably wound at high speed as the respective winding head is displaced along the second portion.

[0317] The use of different winding speeds allows maintaining a substantially constant tension in the strip of product during winding, especially if it is continuously fed.

[0318] In a preferred embodiment, it may be envisaged to move the winding head along a third portion of the working segment, the third portion being preferably substantially parallel to the first portion and / or the second portion, the winding head being preferably displaced along the third portion in a direction coinciding with the feed direction.

[0319] These characteristics allow optimal utilization of the movement of the winding head in order to wind the strip-like product as quickly as possible, taking into account the fact that during winding the winding head moves and at the same time the strip-like product continues to be supplied.

[0320] Preferably, the at least one strip advances at a substantially constant speed along a segment provided between the entrance and exit portions at which the strips are individually provided.

[0321] In a preferred embodiment, it may be envisaged to store an amount of at least one strip before it is gripped by the winding head. Preferably, the stored amount is variable during a displacement of the winding head.

[0322] Preferably, the strips comprise a conductor strip and a separator strip.The method includes storing at least one conductor strip during advancement between the entrance portion and the exit portion.

[0323] These properties also make it possible to envisage a step in which at least one of the strips continues to advance but is not fed to the winding head and in particular is not wound up, in this way the cutting step can be better controlled and / or in the case of strip-like articles formed by several overlapping layers strips of different lengths can be provided.

[0324] Preferably, it may be envisaged to slow down or stop the supply of the strip or strips, with a variable amount of the strip or strips being stored when the supply is slowed down or stopped.

[0325] In this way, storage of the strip can be performed during deceleration or stopping, thereby avoiding tension in the strip, and a single strip can be advanced continuously without being fed through the outlet portion of the feed unit.

[0326] Preferably, the outlet portion is displaced, preferably along a displacement direction, when the strip-like article is retracted.

[0327] Preferably, the winding heads move simultaneously while maintaining a substantially constant distance from each other.

[0328] Preferably, it moves integrally with the winding head outlet section.

[0329] In this way, for example, all strips forming a strip-like article can be stored simultaneously when the moving device, and thus the movable part, moves along a first part of the working segment, and the strips thus stored can be rapidly wound up when returning to the second part of the working segment.

[0330] Preferably, storing the at least one strip comprises varying the distance traveled by the at least one strip between the entrance portion and the exit portion.

[0331] This feature also allows, when a strip-like article is formed by a number of overlapping strips, the advancement of a single strip, or a particular strip, to be offset relative to the remaining strips without the need to stop the advancement of the strips.

[0332] Preferably, the working segment comprises a substantially straight segment.

[0333] The presence of a straight segment along which the winding takes place is particularly advantageous in order to avoid undesirable tension conditions on the strip-like product.

[0334] In a preferred embodiment, it may be envisaged to eject the coil after at least partial winding of the strip, wherein the winding head returns along the working path to a gripping position so as to grip a portion of the strip-like article after ejection of the coil.

[0335] These characteristics also allow the method of the present invention to perform operations in a cyclical manner, advantageously providing an operating portion where the winding head winds and creates a coil, and a reset segment where the head can return to the proper position to restart the cycle.

[0336] Preferably, the plurality of winding heads comprises at least a first winding head and a second winding head. The method includes varying a distance between the first winding head and the second winding head along the working path.

[0337] By varying the distance between the two winding heads, in particular between the step where winding takes place and the step where the strip-shaped product is cut, the step of making the coil can be efficiently managed.

[0338] Preferably, it may be envisaged to bring the first winding head close to the second winding head along the working path in preparation for the step of cutting the strip-like article.

[0339] In this way, the cutting of the strip-like product takes place between two winding heads which minimize the dimensions of the two flaps of the strip-like product resulting after the cut, one head being as close as possible to the other head.

[0340] Preferably, it may be envisaged that while the first winding head is gripping a portion of the strip-like article, the first winding head is moved away from the exit portion and the second winding head is positioned at an intermediate position between the first winding head and the exit portion.

[0341] This property also allows a second winding head to be positioned to grip the strip-like product while the other winding head is still winding the strip-like product, or in any case gripping the strip-like product itself, so that the strip-like product is still being wound on the first winding head when the second winding head grips it.

[0342] Preferably, as the first winding head moves along the third portion, the second winding head preceding the first winding head moves along the first portion.

[0343] This property allows the overall dimensions of the device to be optimized and at least partially allows the winding of two coils to be performed simultaneously, where, after cutting the strip-like article, the first winding head finishes winding the remaining flaps along the third portion and the second winding head starts winding along the first portion.

[0344] Preferably, the step of gripping the portion of the strip-like article comprises the step of placing the portion of the strip-like article between a pair of pins, where at least one of the pins is movable to engage with the other pin holding the strip-like article between them.

[0345] In this way, strip-like goods can be gripped and blocked for winding in a simple manner as part of a continuous and automated process.

[0346] Preferably, the pins are movable along an extraction direction which is transverse, preferably perpendicular, to the feed direction of the strip-like products.

[0347] This characteristic means that as the head moves, one pin approaches the strip, and another pin approaches the first only when it reaches the strip.

[0348] Preferably, both pins are movable and the method includes the steps of moving the pins independently of each other to grip portions of the strip-like article, and, after the strip-like article has been wound into a coil, moving the pins in conjunction with each other to eject the coil from the winding head.

[0349] In this way the same pin can be advantageously used to grip the strip-like article to begin winding, and to eject the coil once wound.

[0350] It should be noted that some steps of the above-described methods may be independent of the reported order of execution. Furthermore, some steps may be optional. Furthermore, some steps of the methods may be performed iteratively, or in series or parallel with other steps of the methods. [Brief description of the drawings]

[0351] The features and advantages of the invention will become apparent from the detailed description of preferred embodiments thereof, given as non-limiting examples with reference to the accompanying drawings, in which: [Figure 1] FIG. 2 is a schematic front view of the device according to the invention; [Diagram 2] 1 is a perspective view of an apparatus made in accordance with the present invention; [Diagram 3] 1A-1D are schematic front views of the device according to the invention during the operating steps; [Figure 4] 4A to 4C are schematic front views of the device according to the invention during different operating steps than in FIG. 3; [Diagram 5]5A-5C are schematic front views of the device according to the invention during different operating steps than those in FIGS. 3 and 4; [Figure 6] 6A to 6C are schematic front views of the device according to the invention during different operating steps than those in FIGS. 3 to 5; [Figure 7] 7A to 7C are schematic front views of the device according to the invention during different operating steps than those in FIGS. 3 to 6; [Figure 8] 8A to 8C are schematic front views of the device according to the invention during different operating steps than those in FIGS. 3 to 7; [Figure 9] FIG. 2 is a further perspective view of the device according to the present invention, with some components removed for clarity of illustration; [Figure 10] FIG. 2 shows a schematic perspective view of an alternative embodiment of the device according to the invention; [Figure 11] FIG. 2 is a schematic diagram showing two non-coincident orientations according to the present invention. [Figure 12] 4 shows an alternative embodiment of the mobile part of the supply unit of the device according to the invention, which is moved to store the amount of strips. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0352] 1 and 2, an apparatus for manufacturing a coil B made in accordance with the present invention is generally designated by the reference numeral 100.

[0353] In a preferred embodiment, the device 100 is intended to carry out the winding of a strip-like article N intended for the production of an electrochemical cell.

[0354] However, it should be noted that this is an example of a possible embodiment, and that the device 100 according to the invention may also be for winding strip-like articles intended for different applications, even in fields other than those related to the production of electrochemical cells.

[0355] For example, in the field of energy storage, the invention can be applied to the manufacture of rolled elements for batteries and supercapacitors.

[0356] In some embodiments, such as that shown in Figure 1, the device 100 may be used in a production line for coils for electrochemical cells, in which a strip-shaped article N is produced by assembling a plurality of strip-shaped articles N1, N2, N3, N4, preferably layered one on top of the other.

[0357] Such a strip advantageously comprises at least two conductor strips N1, N3 and two separator layers N2, N4, which are arranged alternately to form a strip-like article N.

[0358] In this way, the separator strips N2, N4 are able to keep electrically separated from each other the two conductor strips N1, N3 which are spirally wound to form a coil for the electrochemical cell.

[0359] In a preferred embodiment, the strips N1, N2, N3, N4 are provided by a suitable delivery device 6. By way of example, Fig. 1 shows an embodiment of a separator strip delivery device 6, which may be formed by a large coil on which the strips are collected as they are unwound and thus provided during operation of the apparatus.

[0360] The strips provided by the delivery device 6 are then fed to a supply unit 2 which, in a preferred embodiment, performs inter-strip combination to form a strip-like article N before being wound up by a relative winding unit 1, as will be described in more detail below.

[0361] The supply unit 2 preferably comprises an inlet portion 21 adapted to receive the strip from the respective delivery device 6 and an outlet portion 22 through which the strip-like article N passes as it emerges from the supply unit 2 and is supplied to the winding unit 1.

[0362] In this way, between the inlet section 21 and the outlet section 22 a feed path 8 for the strip is defined.

[0363] It should be noted that the strip may pass through further units, for example for pre-treatment of the strip, before being fed to the supply unit 2. For example, the conductor strip may be subjected to a preliminary etching treatment to form a relative outer edge in order to favour the connection with further conductor parts in the electrochemical cell.

[0364] As mentioned above, the strips N1, N2, N3, N4 can be combined in a supply unit to form a strip-like article N that is wound up to make a coil.

[0365] For this purpose, the strips N1, N2, N3, N4 advance along different directions so as to converge towards a coupling roller 23 shown in FIG. 9, on which they are all partially wound up so that, on the downstream side of the strips, there is a single multi-layer structure forming the strip-like article N.

[0366] In a preferred embodiment, the strips N1, N2, N3, N4 are fed successively into the feed unit 2.

[0367] In other words, each of the strips, or possibly one or more of the aforementioned strips, is introduced into the supply unit 2 without any stopping and proceeds at a speed greater than zero, preferably substantially constant.

[0368] However, it may be necessary to slow down the advancement of one or more strips due to the need to provide an interruption of one or more strips forming the strip-like article N, or other operational needs related to the particular process being performed.

[0369] For example, when preparing a coil intended for the manufacture of an electrochemical cell, the end portions of the strip-like article wound to form the coil may be provided in such a way that the strips forming the anode and cathode, respectively, are absent, in other words the coil may have end flaps in which only the two separator strips are present, overlapping each other.

[0370] For this and other purposes, there can be provided between the inlet part 21 and the outlet part 22 of the device the presence of a storage device 4 configured to store a plurality of strips N1, N2, N3, N4 in at least one quantity.

[0371] As shown in the embodiment of Figure 3, in a preferred embodiment, the storage device 4 comprises at least one movable element 4A configured to be moved to vary the overall length of the feed path.

[0372] The amount of stored strip may be variable, i.e., the amount of stored strip may be provided to be variable in length during different steps of the process to meet specific needs as discussed above.

[0373] For this purpose, a device for actuating the storage device 4 can be provided, which displaces the storage device 4 to vary the amount of strips stored.

[0374] As shown in the example of figure 3, the mobile element 4A may comprise at least one mobile roller 40 on which a strip of a certain amount is wound.

[0375] The strip is then wound up around a movable roller 40 and at least one fixed roller. In this way, by varying the distance between the two rollers, the length of the path that the strip must travel between the inlet section 21 and the outlet section 22 can be varied, effectively storing the desired amount.

[0376] In this way, for example considering the example of FIG. 3, the length N1 of the strip can be increased by lowering the movable roller 40 and, considering a constant or substantially constant forward speed at the inlet to the supply unit 2, the part of the strip at the outlet portion can be slowed down or stopped relative to the other strips.

[0377] It should also be noted that in a preferred embodiment, the operation of the movable roller 40, and more generally the storage device 4, may be associated with a strip holding device 26A configured to slow down or stop the supply of one or more strips.

[0378] In other words, the operation of the storage device 4 may be coordinated with the operation of the holding device 26A such that the storage device 2 stores the strip N when the holding device 26A slows down or stops feeding the strip.

[0379] For example, in some embodiments, the presence of, for example, a gripper 26 as illustrated in FIG. 2, or other similar holding element, may be provided to act on the strip and slow the movement of a portion of such strip when it is desired to stop or slow the strip.

[0380] The grippers 26 may advantageously be movable so as to control their movement and thereby regulate the advancement speed of the respective strips.

[0381] The gripper 26 may also be associated with a relative knife 27 which, if necessary, severs one of the strips, creating an interruption in the continuity of this strip within the overall strip-like article N.

[0382] 1 and 2, a winding unit 1 is disposed immediately downstream of the supply unit 2 so as to receive the strip-like article N formed thereby.

[0383] Preferably, the strip-like product N is supplied by being displaced along a supply direction f, which in a preferred embodiment corresponds to the direction in which the strip-like product N moves after being formed by combining the individual strips N1, N2, N3, N4, and possibly also corresponds to the direction envisaged between the roller 23 and the winding unit 1.

[0384] In general, however, the overall advance direction of the strip-like articles N can be defined according to the characteristics of the supply unit 2 and the way in which the strips are combined therein.

[0385] Referring again to Figures 2 and 3, in a preferred embodiment, the winding unit 1 comprises a plurality of winding heads 10, each of which is capable of winding a strip-like article N according to a method described in more detail below.

[0386] As shown diagrammatically in FIG. 3, the winding head 10 is movable within a working path P which is preferably closed.

[0387] The movement of the winding heads 10 is realised by means of respective movement devices 3 which enable each of the heads to move along a working path P.

[0388] In some embodiments, such as for example shown in FIG. 2, the transfer device 3 comprises a rotor 30 rotatable about an axis of rotation C.

[0389] The rotatable body 30 supports a number of extendable arms 31 which are preferably hinged at one end to the rotatable body 30 and which in turn support a respective winding head 10 at their opposite end.

[0390] Advantageously, the combination of a rotatable body 30 and an extendable arm 31 allows the necessary displacements for the winding head to follow the working path P.

[0391] Thereby, in a preferred embodiment, the winding head 10 moves according to a trajectory that includes at least one rotation around the rotation axis C of the moving device 3 and a translation and / or rotation around a further axis different from the rotation axis C.

[0392] Thus, in the embodiment shown in the figures, it can be observed how rotation about a further axis is achieved by swinging of the arm 31 about an axis through the end connected to the rotatable body 30.

[0393] However, it will be apparent that various combinations of such operations are contemplated, either simultaneously or one after the other.

[0394] 10 shows an alternative embodiment of the invention in which the winding head 10 is fixed directly to the rotatable body 30, thus without the use of telescopic arms, and advantageously the rotatable body 30 is also movable about its axis of rotation C, as well as in a displacement direction d in which the rotatable body 30, and generally the displacement device 3, are displaceable.

[0395] Referring again to FIG. 2, in some embodiments, each of the winding heads 10 supports a gripping device 11 configured to grip a portion of the strip-like article N.

[0396] The winding of the strip-like product N can thus be achieved by rotating the gripping device 11 about the winding axis X. By gripping one end of the strip-like product N or, more generally, part of it and rotating this end or part, it is indeed possible to wind the strip-like product N obtaining a helical configuration forming a coil.

[0397] Referring now also to FIG. 9, each of the gripping devices 11 preferably comprises a pair of pins 12, 13 which clamp the strip-like article N.

[0398] At least one of the two pins is movable so that it can join with the other pin which holds the strip-like article N therebetween.

[0399] The pins 12, 13 are arranged substantially parallel to the winding axis X of the strip-like article and can also be rotated to effect the winding of the turns.

[0400] At least one of the two pins may be movable along an exsegmentation direction e in order to enable the pin to grip the strip-like article N. In this way, the first pin 12 of the pair can approach the strip-like article N while the opposing head 10 moves along the path P.

[0401] The movable second pin 13 is instead intended to be located at a downstream position relative to the fixed pin 12 along the path P. In this way, the strip-like article can be provided between the two pins 12, 13.

[0402] For this purpose, the direction of extension and therefore the movement of the movable pin 13 is not substantially parallel, or more generally perpendicular, to the axis X, but perpendicular, or more generally transverse, to the feed direction f of the strip-like article N.

[0403] In this way, the second pin 13 can be positioned in a position that does not hinder the first pin 12 from approaching the strip-shaped article N, and once the first pin 12 is positioned, the second pin 13 can be displaced to a position that holds the article N.

[0404] Advantageously, the first pin 12 may be arranged to move simultaneously with the second pin 13 along the exsegmention direction in order to discharge the coil, as will be explained in more detail below.

[0405] 3-8 illustrate the movement of the winding head 10 in a preferred embodiment, and generally the operation of the present invention.

[0406] These figures will be described below with reference to two winding heads 10, although it will be apparent that the same concepts can be applied to any number of heads.

[0407] Thus, FIG. 3 identifies a first winding head 10A and a second winding head 10B, the second winding head being disposed at an upstream position along the working path P relative to the first head 10A.

[0408] In the state of FIG. 3, the first winding head 10A is located adjacent the outlet portion 22 of the supply unit and is in a position to receive the strip-like goods N therefrom.

[0409] This reset segment P2 makes it possible to close the path P and is in particular the segment in which the winding head returns to the start of the working segment P1 after winding the strip-like goods, forming a coil and discharging the coil into a discharge area 7, which is shown diagrammatically in Figures 1 and 2. It is to be noted that in this discharge area 7 the coil B is discharged from the winding unit 1 in order to be transported to other units for making the cells.

[0410] Preferably, the ejection is performed by moving two pins 12, 13 displaced along the exsegmention direction so as to release the coil B from the relative winding head.

[0411] After being gripped by the winding head 10A, the strip-like article N continues to move along the working path in a first part P11 of the working segment P1.

[0412] Preferably, the first portion P11 is straight and moves in line with the feed direction f of the strip-like article N.

[0413] In some embodiments, the supply unit 2 comprises a movable part 20 which is displaceable along a displacement direction d and in which an outlet portion 22 is formed and on which preferably a coupling roller 23 is fixed.

[0414] In some embodiments, the displacement direction d forms an angle with the horizontal of between 30° and 60°, preferably equal to 45°.

[0415] Referring now to FIG. 4, the feed paths 8 of the strips N1, N2, N3, N4 preferably comprise respective storage segments 81 of variable length extending between respective pairs of diverter rollers 24, 25 which preferably run idle.

[0416] Preferably, the storage segments 81 extend substantially parallel to one another and the direction of the strips N1, N2, N3, N4 is diverted by the diverter roller 25 so that each of the strips flows to the coupling roller 23. In some embodiments, such as those shown in Figures 1 to 10, and in particular in Figure 4, the strip N1 is substantially parallel to the displacement direction d of the movable part 20 and aligned with the storage roller 23, so that the presence of the roller 25 is not necessary.

[0417] Advantageously, the distance between the parallel segments 81 is such that it is possible to accommodate the above-mentioned grippers 26 and knives 27 between two adjacent strips in a segment provided between the diverter roller 25 and the coupling roller 23.

[0418] In some embodiments, one roller of each pair of diverter rollers 24, 25 is supported on the movable part 20 for movement therewith, as will be described in more detail below.

[0419] In this way, by moving the movable part 20, the length of the storage segments 81 of each strip can be changed simultaneously.

[0420] Thus, while the mobile part 20 advances, the supply unit 2 can store a quantity of the strip-like articles N between the inlet section 21 and the outlet section 22 .

[0421] In fact, as can be seen by comparing Figures 3 and 4, the length of the storage segment 81, and more generally the length of the path travelled by the strips N1, N2, N3, N4 between the inlet portion 21 and the outlet portion 22, is increased by coordinating the advance of the strips with the displacement of the movable part 20, thereby allowing an effective storage of the respective amounts of strip between these sections.

[0422] Preferably, the displacement of the moving part 20 is associated with the advancement of the strip so as not to generate tension in the strip. Indeed, while the moving part 20 is displacing, the strip can slide on the diverter roller 25, so that the length of the strip between rollers 24 and 25 can be increased without inducing a tension state. Preferably, the displacement speed of the moving part 20, when it coincides with the advancement movement of the strip, is lower than its feeding speed.

[0423] In this way, pulling on the strip during the movement of the movable part 20 can be avoided and this displacement can be made neutral with respect to the movement of the strip.

[0424] In a preferred embodiment, the storage segments 81 extend substantially parallel to one another and remain substantially parallel during and after displacement of the movable part 20, resulting in a change in length.

[0425] This can be achieved by providing the movable part 20 to be displaced along a displacement direction d that is substantially parallel to the storage segment 81. In this way, as the movable part is displaced along the direction d, the storage segment 81 increases or decreases its length by the same amount.

[0426] More generally, the displacement direction d may preferably be substantially parallel to the feed direction f.

[0427] Alternatively, the same result can be achieved by appropriately positioning the rollers 24, 25 through which the storage segment 81 extends.

[0428] In particular, in an alternative embodiment, such as that shown in FIG. 12, it can be provided that, unlike the embodiments shown in the other figures, both roller 24 and roller 25 are aligned with each other and with the displacement direction d of the movable part 20.

[0429] It should therefore be noted that the movement of the mobile part 20 is in this case also associated with a change in the length of each storage segment 81 .

[0430] In some embodiments, the supply unit 2 comprises one or more alignment devices 82 configured to guide the strip N along the supply path 8 in order to avoid, or in any case limit, lateral deviation during advancement of the strip N. For example, the alignment device 82 may comprise an oscillating carriage that biases the strip back to a straight state if the strip deviates laterally relative to its advancement direction.

[0431] Referring again now to FIG. 4, in some embodiments, movement of the winding head along portion P11 may be accompanied by a corresponding movement of the movable part 20 along the displacement direction d.

[0432] It should also be noted that the winding head 10 and the movable part 20 are movable in a coordinated manner, i.e. the movements of the winding head 10 and the movable part 20 are synchronized.

[0433] In this way, it is possible to control the distance between the winding head 10 winding or, more generally, holding the strip-like product, and the mobile part 20 of the winding unit 2. It is thus advantageously possible to provide that the length of the strip-like product N formed between the winding unit 2 and the winding head holding it is minimal or in any case equal to a predetermined distance.

[0434] For example, from FIG. 4 it can be seen that even in this operating position, the first head 10A is located adjacent the outlet portion 22 of the supply unit 2. As shown in FIG.

[0435] To this end, in a preferred embodiment, the displacement direction d may be substantially parallel to the first portion P11 of the working segment P1.

[0436] It should be noted that, as mentioned above, in the context of the present invention, the term "substantially" when referring to the parallelism with respect to the working segment P1 on which the winding takes place is intended to mean that the two directions are parallel, except for deviations related to the winding of the strip-like article N. In fact, during the winding of the strip-like article N, the position of the same contact point on the coil formed varies and does not follow a perfectly straight line, unless compensated for by the movement of the extendable arm 31, and so may deviate from perfect parallelism.

[0437] Thus, as stated above, the term "substantially parallel" will indicate a deviation of ±10°, preferably ±5°, from perfect parallelism.

[0438] The winding head 10 can also start winding the strip-like article N along the portion P11.

[0439] It should be noted in particular that this relates to the ratio between the feed speed vf at which the strip-like goods are supplied by the supply unit 2 and the displacement speed vsp with which the winding head moves along the portion P11.

[0440] In fact, when the supply speed vf is higher than the displacement speed vsp, it is envisaged that in this section the strip-like product N is wound up at a winding speed which compensates for the difference between the two aforementioned speeds.

[0441] In this way, the amount of strip-like product N supplied is wound or stored as described above. Thus, by appropriately influencing the speed of movement of the head during winding and / or holding of the strip-like product N, the strip-like product N can be kept under a substantially constant tension.

[0442] It should be noted that the feed speed vf is preferably determined by the speed at which the delivery coil forming the delivery device 6 is rotated to unwind the strip, forcing it into the delivery device 1 and then into the winding unit 3. More generally, this speed can be determined by the operating mode of the delivery device 6.

[0443] At the same time, the winding of the strip-like article N through the winding head 10 can also contribute to determining the feed speed vf by the pulling action of each strip. If the coil or other delivery device 6 is not motorized and is therefore at rest, the strip can only be advanced by the winding action.

[0444] The tension in the strip is also regulated by a balance between the action of the delivery device 6 and the winding of the strip-like product, in a manner conceptually similar to that illustrated in relation to speed.

[0445] Referring now to FIG. 5, upon reaching a limit of displacement in a direction coincident with the feed direction f, the winding head 10A is displaced in the opposite direction along a second portion P12 of the working segment P1.

[0446] Also in this case, the movement of the head 10A is advantageously associated with a corresponding displacement of the mobile part 20 of the supply unit 2.

[0447] During the movement of the winding head 10A in section P12, the strip-like product N is wound onto the head itself, preferably with a winding speed greater than the winding speed provided in section P11.

[0448] It should be noted that the displacement of the winding head 10 during such winding is performed in a direction that is not coincident with the feed direction f.

[0449] Also, the relative portion P12 is preferably substantially parallel to the feed direction f and, optionally, also parallel to the displacement direction d.

[0450] Also in this case the same considerations apply as discussed above with respect to the term "substantially parallel".

[0451] Thus, while the winding head 10A is moving along the portion P12, it can wind up the amount of strip stored in the previous step.

[0452] Also in this step, the same considerations apply with regard to the feed and displacement speeds of the head as are made with reference to portion P11.

[0453] The feed speed vf, the winding speed vavv and the displacement speed vsp are preferably such in practice as to give the strip-like product N a substantially constant tension.

[0454] As mentioned above, this can be achieved in practice in a preferred embodiment by having the feed speed vf substantially equal the sum of the take-up speed vavv and the displacement speed vsp.

[0455] It should also be noted that, advantageously, the rotatable body 30 of the moving device 3 continues to progress in its rotational movement, while the arm 31 is rotated in the opposite direction, thereby performing a movement opposite to that performed during the movement along portion P11.

[0456] In other words, along the portions P11 and P12 the arm 31 swings back and forth so that the winding head can perform the above-mentioned movements and winding of the strip-like product.

[0457] In the limit position along the segment P12 shown in FIG. 6, the first winding head 6 can be moved away from the outlet portion 22.

[0458] This movement can be achieved by movement of the head itself and / or by displacement of the movable part 20 .

[0459] Therefore, as shown in FIG. 7, sufficient space can be provided so that a second winding head 10B, which is positioned upstream of the first head 10A along the path P, can be interposed between the first winding head 10A and the outlet portion 22.

[0460] Indeed, it should be noted that in a preferred embodiment, the distance between the first winding head 10A and the second winding head 10B can vary along the working path P depending on the operation step of the device 100.

[0461] This characteristic makes it possible to obtain the configuration shown by way of example in Figures 7 to 9, in which the two heads 10A and 10B are at a minimum distance such that the cutting element 51 of the cutting device 5 can be positioned between them, the second head 10B, in turn, being at a predetermined distance, preferably substantially equal to the minimum distance, from the movable part 20 and more generally from the supply unit 2.

[0462] The two heads are preferably aligned along the feed direction of the strip-like article N.

[0463] In this way, relative portions of the strip-like product N can be gripped via the gripping device 11 of the second winding head 10B, as is evident from FIG. 9 and as described above.

[0464] The portions of the strip-like article N can be gripped as described above, in particular by using a pair of pins 12,13.

[0465] In this state, the strip-shaped article N is wound by the first winding head 10A to form a coil B, and is simultaneously gripped by the second winding head 10B.

[0466] In other words, the strip-like article N is gripped simultaneously by both the first winding head 10A and the second winding head 10B.

[0467] Furthermore, even in this position, the strip-shaped product N can be cut at an intermediate position between the first winding head 10A and the second winding head 10B.

[0468] For this purpose, at a position downstream of the supply unit 2, advantageously at the position mentioned above, a cutting device 5 can be provided which is arranged to cut the strip-like article N.

[0469] Indeed, as the embodiment shown in the figures shows, the cutting device 5 advantageously cuts the strip-shaped product N when each winding head 10 is positioned at a predetermined distance from the supply unit 2, advantageously at a distance substantially equal to the minimum distance compatible with the movement mechanism causing the movement of the winding head 10.

[0470] As mentioned above, in conjunction with the cutting, the second winding head 10B approaches the first winding head 10A and is advantageously at a minimum reciprocating distance along the working path P when the strip-like article N is cut.

[0471] The cutting device 5 is shown in its preferred embodiment in FIG.

[0472] Preferably, the cutting device 5 comprises a body 50 supporting a cutting element 51 .

[0473] In some embodiments, the winding head 10 comprises an abutment element 14 which is arranged in a position such that the strip-like article N is clamped between the abutment element 14 and the cutting device 5 .

[0474] The abutment element 14 preferably has a seat 14 a configured to receive the cutting element 51 .

[0475] In this way, when the cutting device 5 is approached to the abutment element 14, the body 50 of the cutting device 5 abuts against the abutment element 14 with the strip-shaped article N interposed therebetween, and the cutting element 51 is received in the seat portion 14a, generating sufficient pressure on the strip-shaped article N to obtain its cut.

[0476] It should be noted that prior to the cutting operation of the strip-like article N, the conductor strips N1, N3 may be interrupted and their advancement stopped or slowed down by the gripper system 26 described above.

[0477] In this way, the cuts made by the device 5 can only affect the separator strips N2, N4 which form the strip-like article N following the interruption of the conductor strip.

[0478] 7 and 8, attention can be paid to the action of gripper 26 on the conductor strip and the displacement of movable roller 40 relative to the position of FIG. 6 so as to retract the strip as previously shown.

[0479] In some embodiments, the cutting device 5 is also movable in a direction substantially parallel to the feed direction f. In general, it may be provided that the cutting device is movable in at least one component substantially parallel to this direction. For example, the cutting device 5 is supported on the mobile part 20 or is movable integrally therewith. In this way, it is possible to both bring the cutting device 5 closer to the abutment element 14 and to displace the strip-like article N synchronously. In other words, the cutting device 5 copies the movement of the strip-like article N and moves synchronously therewith when performing the cutting operation.

[0480] Moreover, due to such characteristics, the strip-shaped article N is fed at a feed speed vf that is always greater than zero and is preferably substantially constant. The strip-shaped article can also be cut while moving.

[0481] It should be noted that the strips forming the strip-like articles N can also be advanced continuously in the supply unit 2. In embodiments in which interruptions of the conductor strips or other strips forming the strip-like articles are envisaged, the continuous advance is preferably associated with the possibility of storing the strips. Instead, for strips for which no interruptions are envisaged, they can be advanced continuously through the outlet 22 in succession with the strip-like articles N.

[0482] When the strip-like article N is cut, two flaps are defined, one associated with a first winding head 10A which forms the terminal portion of the coil to be wound thereon, and the other associated with a second winding head 10B which forms the initial portion of the coil B which is subsequently wound.

[0483] Preferably, the process for making the coil B is substantially parallel to the first portion P11 and the second portion P12 and provides a third portion P13 of the working segment P1 to which the winding head 10A is displaced after cutting of the strip-shaped article N.

[0484] In a preferred embodiment, the winding head moves again along a third portion P13 in a direction coincident with the feed direction f.

[0485] Preferably, the moving device 3 is configured such that when the first winding head 10A moves along the third portion P13, the second winding head 10, which has advantageously just gripped the strip-shaped article N, moves along the first portion P11 while sequentially performing the steps described above with respect to the first winding head 10A.

[0486] Meanwhile, along section P13, the first winding head completes the winding of the flap of the strip-like article N produced following the cutting and finishes to produce the coil B.

[0487] As mentioned above, the winding of the strip-like article N to make the coil B can take place in each of the three parts P11, P12, P13.

[0488] Preferably, the winding takes place mainly, ie to a greater extent, along the second portion P12.

[0489] However, winding may also be partially performed in other areas.

[0490] Indeed, in a preferred embodiment, the winding of the strip is carried out along the first portion P11 in an amount between 5% and 15%, preferably 10%, of the overall length of the strip-like article forming a single coil, along the second portion P12 in an amount between 70% and 90%, preferably 80%, and along the third portion P13 in an amount between 5% and 15%, preferably 10%.

[0491] Thereafter, the displacement of the first winding head 10A continues until it reaches the discharge area 7 where the coil B is discharged from the winding unit 1.

[0492] In some embodiments, the apparatus 100 may further comprise a working unit 60 through which the winding head 10 passes together with the coil B before reaching the discharge area 7 .

[0493] By way of example, the further working unit 60 may comprise a folding device arranged to fold the two opposing axial ends of the coil, in effect providing that the conductor strips each project axially, one on one side and the other on the other, to be folded to form a single conductor part intended to be connected to the anode / cathode ends in the cell once assembled.

[0494] In some embodiments, application of a closure element on the coil B may also be provided, which closure element is configured to prevent unwinding once discharged from the winding head 10. Such a closure element may for example be represented by a strip-like element that is applied circumferentially to the coil in order to close the end flaps of the strip-like element.

[0495] After discharging the coil, the winding head 10A begins to pass along the reset segment P2 to transition from the discharge position to a gripping position where the winding head 10 can grip a portion of the strip-like product N, as described above.

[0496] The above steps can be repeated cyclically for each winding head 10 of the winding unit 1 .

[0497] As mentioned above, FIG. 10 shows an exemplary variant of the device according to the invention.

[0498] In this variant, the moving device 3 is arranged to move integrally with the movable part 20 of the winding unit 2 .

[0499] Therefore, the moving device 3 can be supported by the movable part 20 so as to be rotatable about the rotation axis C.

[0500] Thus, in an embodiment in which the moving device 3 can move as a whole along the displacement direction d, as in the example shown in the figure, the winding head 10 remains in a substantially fixed position relative to the rotatable body 3, so that their mutual distance does not change.

[0501] In other words, in this case the moving head 10 can not only rotate by itself in order to wind up the strip-like product N, but also be displaced by following the movement of the rotating body of the moving device 3, preferably also its linear displacement. In the embodiment shown in Fig. 10, as in other more general embodiments in the preferred embodiment not shown, such a movement includes both a rotation about the axis C and a translation along the displacement direction d.

[0502] However, it should be noted that more generally, the movement of the moving head 10 can always be caused by any rotation and any translation or further rotation in addition to the rotation performed in this case to wind up the strip-shaped article N.

[0503] However, these movements do not cause any variation in the mutual distance between the winding heads 10.

[0504] It is also possible to provide a combination between this embodiment and the above-mentioned embodiment in which the head distance is variable.

[0505] More generally, all elements described above in connection with the embodiment shown in FIG. 10 are provided by the present invention and can be combined with all possible embodiments described above.

[0506] It goes without saying that those skilled in the art can make further modifications and variations to meet the needs of specific and fortuitous applications, while still falling within the scope of protection defined by the appended claims.

Claims

1. An apparatus (100) for producing a coil (B) for an electrochemical cell, preferably intended for the production of a battery, comprising: a supply unit (2) configured to supply at least one strip-like article (N) comprising one or more strips, preferably comprising conductor strips (N1, N3) and separator strips (N2, N4), said supply unit (2) comprising an outlet portion (22) through which said strip-like article (N) is supplied to said winding unit (1), and an inlet portion (21) preferably adapted to receive said at least one strip from a respective delivery device (6); A winding unit (1), at least one winding head (10), each of which is configured to wind said strip-like article (N) so as to create said coil (B); a movement device (3) for moving said winding head (10), configured to displace said winding head (10) along a working path (P), and a storage device (4) configured to store a variable amount of at least one of said strips (N1, N2, N3, N4) between said inlet portion (21) and said outlet portion (22); A winding unit (1) including an actuation device (4) for actuating the storage device (4), configured to displace said storage device (4) so ​​as to vary the amount of said strips stored; An apparatus comprising:

2. 2. The apparatus according to claim 1, wherein the storage device (4) comprises at least one movable element (4A) configured to change an overall length of a feed path (8) defined between the inlet portion (21) and the outlet portion (22) by moving the movable element (4A).

3. 3. Apparatus according to claim 2, wherein the supply unit (2) comprises a movable part (20) in which the outlet portion (22) is formed, and the movable element (4A) is formed by the movable part (20).

4. 4. The device according to claim 3, wherein the supply unit (2) is configured to vary the overall length of the supply path (8) by moving the movable part (20).

5. The device according to any one of claims 2 to 4, wherein the movable element (4A) comprises at least one movable roller (40), and the at least one strip is wound around the movable roller (40) and the at least one fixed roller so as to vary the overall length.

6. Apparatus according to any one of claims 1 to 5, wherein the supply unit (2) comprises a holding device (26A) for holding one or more of the one or more strips (N), said device being configured to slow down or stop the supply of at least one of the one or more strips (N1, N2, N3, N4) through the outlet portion (22), and wherein the storage device (4) is preferably configured to store the strip when the holding device (26A) slows down or stops the supply of the strip.

7. Apparatus according to any one of claims 1 to 6, wherein the supply unit (2) comprises a coupling roller (23), and the strips (N1, N2, N3, N4) are arranged to converge towards the coupling roller (23) on which the strips (N1, N2, N3, N4) are wound, whereby the strips are grouped downstream of the coupling roller (23) to form the strip-like product (N).

8. 8. Apparatus according to claim 7, wherein the outlet portion (22) is defined by the coupling rollers (23).

9. 9. Apparatus according to claim 8 when dependent on claim 3, wherein the coupling roller (23) is connected to the movable part (20).

10. The apparatus according to any one of claims 1 to 9, wherein the winding head (10) is configured to wind the strip-like article (N) during a displacement of the winding head (10) along an operating segment (P1) of the working path (P) by the moving device (3) so as to create the coil (B).

11. An apparatus according to any preceding claim, wherein a respective feed path is defined for each of the strips, the feed path including a respective storage segment.

12. 12. The apparatus of claim 11, wherein the storage segments are preferably substantially parallel to one another.

13. 13. Apparatus according to claim 11 or 12, wherein the supply unit is configured to vary the longitudinal extension of each of the storage segments.

14. The apparatus of claim 13 , wherein the storage devices are configured to simultaneously vary the longitudinal extent of the storage segments.

15. A method (100) for making a coil (B) for an electrochemical cell, preferably intended for the production of a battery, said coil (B) being made by winding at least one strip-like article (N), said strip-like article (N) comprising one or more strips, preferably conductor strips (N1, N3) and separator strips (N2, N4), Providing at least one winding head (10) movable along a working path (P); winding the strip-like product (N) by the winding head (10); storing a variable amount of at least one or more of said strips at a position upstream of said winding head (10), said stored amount being variable during displacement of said winding head (10); A method comprising:

16. 16. The method according to claim 15, wherein the strip-like product (N) is stored by moving the outlet portion (22), the outlet portion (22) being preferably formed in a movable part (20) of a supply unit (2) which supplies the strip-like product (N) to the winding head (10).

17. 17. The method of claim 16, comprising slowing or stopping the feeding of one or more of the strips, and a variable amount of one or more of the strips is stored when the feeding is slowed or stopped.

18. 14. The method according to any one of claims 11 to 13, wherein the strips comprise conductor strips (N1, N3) and separator strips (N2, N4), comprising the steps of combining the strips to form a strip-like article (N) and storing at least one of the conductor strips (N1, N3) while it advances between an entrance section (21), in which the strips are individually provided, and the exit section (22).

19. 20. The method of claim 18, wherein said step of storing at least one said strip comprises the step of varying a distance traveled by at least one strip between said inlet portion (21) and said outlet portion (22).

20. 20. The method according to claim 19, wherein the strip-like articles (N) are supplied by a supply unit (2) having a movable part (20) including the outlet portion (22), and the distance travelled by at least one of the strips is varied by displacement of the movable part (20).

21. The method according to any one of claims 15 to 20 when dependent on claim 16, wherein combining the strips (N1, N2, N3, N4) to form the strip-like article (N) comprises partially winding the strips on a coupling roller (23).

22. 22. The method according to claim 21, wherein the outlet portion (22) is defined by the coupling roller (23).

23. A method according to any one of claims 15 to 22, comprising the step of winding the strip-like article (N) by a winding head (10) during the displacement of the winding head (10) along a working segment (P1) of the working path (P).

24. A method according to any one of claims 15 to 23, comprising varying the length of each of the storage segments simultaneously.

25. 25. The method of claim 24, wherein the length of each of the stored segments is changed by the same amount.

26. 26. The method of claim 24 or 25, comprising maintaining the storage segments substantially parallel to one another while varying the length of the storage segments.

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