Patent Description:
The present invention relates to a system and to a related method for replacing a reel of material, in particular a reel of a strip of electrode or separator, for the production of electrical energy storage devices.

In particular, the present invention is advantageously but not exclusively applied to the production of rechargeable batteries to which the following description will explicitly refer without thereby losing generality, for example planar batteries in metal can or enveloped (commonly called of the pouch type), or cylindrical batteries composed of cylindrical windings (for example of the jelly roll type).

Automatic machines for the production of electrical energy storage devices are known, and in particular of rechargeable batteries or of capacitors.

Rechargeable batteries usually comprise two layers of electrode (cathode and anode) and at least two layers of separator arranged staggered with respect to one another according to an alternated electrode-separator-electrode-separator scheme.

Within the production process, such layers are each provided in a strip shape initially wound in a reel.

In the case of cylindrical batteries, it is known to feed by means of respective feeding units of the aforementioned automatic machines the strips of electrode and the strips of separator along different feeding paths which all converge towards a rotating winding core, which is configured to retain and wind (generally about an elongated-shaped support) the strips of electrode and the strips of separator arranged staggered with respect to one another in an alternated manner, so as to form a cylindrical winding.

Subsequently, the cylindrical winding is typically closed by a layer of protective tape and fed to a further unit for forming the battery.

In the case of planar batteries in metal can or enveloped, also known as pouch batteries, the strips of electrode and separator are fed along respective feeding paths for converging all of them towards a rolling unit, inside which they are laminated with respect to one another. If necessary, during the lamination, the aforementioned strips of electrode and separator are arranged between two further protection layers (these too strip-shaped). Such protection layers are configured to protect the strips of electrode and separator inside the rolling unit and are usually removed at the exit from this unit.

Whatever type of rechargeable battery or capacitor is produced, the automatic machines of the aforementioned type generally comprise an aforementioned feeding unit of the strips of separator and electrode, which are initially wound in respective reels each supported by a relative support shaft or spindle.

During the production process, the feeding unit must constantly be provided with full reels of strips of electrode and separator so as to ensure the continuity of the process.

The need is thus known to provide for the change of the exhausted reels with full reels. Typically, the change of each exhausted reel with a full one is carried out manually by an operator.

Generally, the feeding unit is conveniently adapted to support two reels for each strip of material. In particular, the feeding unit comprises a pair of support shafts or spindles for each strip of material to be fed, one of which spindles supports the unwinding reel and the other of which spindles supports a full reel.

In accordance with the foregoing, in order to prevent interruptions in the production, a feeding unit of known type includes a splicing device (commonly known as splicer) configured to automatically join to one another the final flap of the exhausting reel with the initial flap of the full reel, for each pair of spindles (and thus of reels of a given strip of separator or electrode).

To such regard, it is sufficient for the operator to manually arrange the initial flap of the full reel (already on-board the respective support spindle) at the splicer. At this point, the splicing will take place automatically upon the exhaustion of the unwinding reel.

Once the "old" reel is exhausted, the latter is changed (replaced) with another full reel, whose initial flap, when the full reel is already on-board the feeding unit, is unwound (generally a closing tape is removed) and is arranged at the splicer, as described above.

In such manner, the change of the reels of each strip of separator or electrode can take place without interrupting the production.

Document <CIT> discloses an electrode roll supplier including an electrode roll loading unit disposed in a frame and into which an electrode roll is loaded; a transfer unit disposed to be movable along the frame, and transferring the electrode roll loaded into the electrode roll loading unit to an electrode roll supply area.

Although the machines and the methods for changing the reels of the aforementioned type are functionally and structurally valid, the Applicant observed that these are susceptible of further improvements, in particular with regard to the production speed, the minimisation of errors and the safety of the operators.

The object of the present invention is to provide a system and a related method for replacing a reel of material for the production of electrical energy storage devices, which are highly reliable and limited in cost, and allow meeting at least some of the requirements specified above and connected to the machines of known type.

According to the invention, this object is achieved by a system for replacing a reel of material for the production of electrical energy storage devices and by a related method according to what claimed in the following independent claims and, preferably, in any one of the claims directly or indirectly dependent on the independent claims.

The claims describe preferred embodiments of the present invention forming integral part of the present description.

In order to better understand the present invention, some non-limiting preferred embodiments are described in the following, by mere way of example and with the aid of the accompanying drawings, wherein:.

With reference to the accompanying figures, reference numeral <NUM> indicates, as a whole, a system for replacing a reel <NUM> of material for the production of electrical energy storage devices, in particular a reel <NUM> of a strip of electrode (cathode or anode) or separator starting from which the storage devices are produced.

More specifically, the system <NUM> is adapted to be used for carrying out a reel change in a production assembly <NUM> of the rechargeable batteries comprising:.

It is specified that, in the present description and in the appended claims, "reel change" is understood as the replacement, carried out by means of the system <NUM> according to the present invention, of an exhausting or exhausted reel, i.e. that has almost finished or has finished unwinding the relative strip of material, with a full reel, i.e. still containing the entire strip of material.

The feeding unit <NUM> comprises a plurality of support shafts or spindles <NUM> each adapted to receive and support a respective reel <NUM> in rotation for determining the unwinding of the relative strip of electrode or separator from the latter.

During the production process, the feeding unit <NUM> must be constantly provided with full reels <NUM> of strips of electrode and separator so as to ensure the continuity of the process.

The feeding unit <NUM> is conveniently adapted to support two reels <NUM> for each strip of electrode or separator. In particular, the feeding unit <NUM> comprises a pair of spindles <NUM> for each strip of material to be fed, one of which spindles <NUM> supports the unwinding reel <NUM> and the other of which spindles <NUM> supports a full reel <NUM>.

In accordance with the foregoing, in order to prevent interruptions in the production, the feeding unit <NUM> includes a splicing device or splicer (known per se and not described in detail nor illustrated) configured to automatically join to one another the final flap of the exhausting reel <NUM> with the initial flap of the full reel <NUM>, for each pair of support spindles <NUM> (and thus of reels <NUM> of a given strip of separator or electrode).

Specifically, the splicing device comprises a receiving member having a gripper <NUM> adapted to grip an initial flap of the full reel <NUM>.

Therefore, the need is felt to provide for the change of the exhausted reels <NUM> with full ("new") reels <NUM>, so as to ensure the continuity of the production process.

As visible in the accompanying figures, the system <NUM> comprises:.

In an embodiment, the vehicle <NUM> is defined by a conveyor trolley, preferably of the known type, comprising a base body <NUM>, a plurality of wheels <NUM> fixed to the base body <NUM> and a support upright <NUM> fixed to the base body <NUM> and extending from the latter, preferably in vertical direction with respect to a resting ground of the wheels <NUM>. In particular, the wheels <NUM> are rubber wheels. In other non-limiting embodiments, the vehicle <NUM> is configured to move on rails.

The spindle <NUM> is fixed to the upright <NUM> and extends cantilevered from the latter.

Conveniently, the vehicle <NUM> is provided with: sensors (known per se and not described in detail nor illustrated) configured to allow the self-driving of the vehicle <NUM>, for example a radar o LIDAR system, a photoelectric barrier safety system, a laser system or the like; and with a control unit (not illustrated) configured to manage the data detected by the sensors and to control on the basis of these data, the trajectory of the vehicle <NUM> from the storage or receiving station to the change station, thus determining the self-driving thereof.

In an embodiment, the vehicle <NUM> is self-propelled on a driving track by means of a slide fixed to the base body <NUM>. For example, the assembly comprises a system of rails defining the respective trajectories of the vehicle(s) <NUM> from the storage or receiving station to the change station.

According to the invention, the system comprises a gripping member <NUM> carried by the vehicle <NUM> and comprising at least one gripper <NUM> configured to receive and grip an initial flap 2a of the reel <NUM> supported by the spindle <NUM> and to keep such initial flap 2a tensioned (or in tension) along an initial unwinding path T of the same (illustrated in <FIG>).

Conveniently, the gripping member <NUM>, and in particular the gripper <NUM>, is arranged along the unwinding path T.

In an embodiment, the system <NUM> further comprises a blocking device (not illustrated), for example a brake, carried by the vehicle <NUM> and configured to block an angular displacement of the reel <NUM> about a rotation axis coaxial to the support spindle <NUM>, in use, the reel <NUM>, so as to keep the initial flap 2a tensioned along the unwinding path T.

It is understood that the blocking device could be defined by a stop mechanism acting on the reel <NUM> from the outside, for example a counter-roller acting thereon by pressure, thus blocking the unwinding of the strip of material wound in the reel <NUM>. In such case, the architecture of the blocking device is simplified with respect to the previous case. In other non-limiting cases, the blocking device could be defined by an electric motor kept in torque and configured to move in rotation the spindle <NUM>.

According to a further aspect of the present invention, the gripping member <NUM> comprises a pair of grippers <NUM> arranged spaced apart from one another along the unwinding path T (i.e. aligned with the unwinding path T but arranged at a non-null distance from one another) and configured to grip the initial flap 2a at spaced apart portions 2b of the latter, so that a central portion 2c of initial flap 2a between the gripped portions 2b is kept tensioned (<FIG>).

In other words, the presence of two grippers <NUM> instead of only one, ensures that the central portion 2c of the initial flap 2a remains tensioned during the movement of the vehicle <NUM> and during the transfer of the reel <NUM>, as it will be apparent in the following.

In such case, the aforementioned angular blocking device of the reel <NUM>, which can be relatively complicated and expensive to manufacture, is not necessary, resulting in a simplified architecture and in a reduction in costs.

Advantageously, each gripper <NUM> is movable, in particular both grippers <NUM> are movable in a simultaneous and integral manner, between a retracted position (<FIG> and <FIG>) in which it grips the initial flap 2a and determines a (for example places it in) tension thereof, and an advanced position (<FIG>) in which it delivers the tensioned initial flap 2a to the feeding unit <NUM>, and in particular to the gripper <NUM> of the splicing device or splicer of the same.

To such regard, the system <NUM> comprises a pushing device <NUM> configured to move each gripper <NUM> from the retracted position to the advanced position.

Specifically, the pushing device <NUM> is also configured to move the reel <NUM> from the support spindle <NUM> of the vehicle <NUM> to the support spindle <NUM> of the feeding unit <NUM> which needs to receive the full reel <NUM>.

More precisely, the spindle <NUM> is configured to operatively couple to the spindle <NUM> of the feeding unit <NUM> which needs to receive the full reel <NUM> when the vehicle <NUM> is at the change station.

In an embodiment, the pushing device <NUM> is defined by a push bar controlled by an electric actuator, for example a linear or rotary motor with endless life, or a pneumatic actuator.

More specifically, such push bar is operatively connected to the grippers <NUM> and is extractable, for example by means of the aforementioned electric actuator, from the upright <NUM> for moving the grippers <NUM>.

In an alternative embodiment, the pushing device <NUM> is defined by a spring pin.

In an alternative embodiment, the pushing device <NUM> is defined by the spindle <NUM> in telescopic configuration for extending towards the feeding unit <NUM> or for returning towards the upright <NUM>.

Preferably, the spindle <NUM> comprises a shaped terminal <NUM> configured to couple to the spindle <NUM> of the feeding unit <NUM> by means of a shape coupling (<FIG>, <FIG>, <FIG> and <FIG>).

More in particular, the spindle <NUM> comprises a relative terminal <NUM> shaped complementarily to the terminal <NUM> for obtaining the aforementioned shape coupling.

In such manner, the change of the reel <NUM>, i.e. its transfer from the spindle <NUM> to the spindle <NUM> by means of the pushing device <NUM> takes place in a safe manner and only when the coupling to one another has actually taken place.

In the described example, the terminal <NUM> has a conical cavity, whereas the terminal <NUM> has a conical shape complementary to the cavity.

The aforementioned conical shape is particularly advantageous since it defines an invitation to the coupling of the terminal <NUM> in the terminal <NUM> which minimises and eliminates a possible misalignment of the spindles <NUM> and <NUM>.

Preferably, each reel <NUM> is wound about a conveniently rigid core <NUM>.

In practice, each core <NUM> is defined by a cylindrical hollow body thus defining a hub of the relative reel <NUM> adapted to be engaged by the spindle <NUM> and/or by a spindle <NUM>.

Conveniently, the grippers <NUM> are carried by (fixed to) a separator <NUM> slidingly mounted on the spindle <NUM> (see to such regard <FIG> and <FIG>) and operatively coupled to the pushing device <NUM>.

The separator <NUM> is also operatively connectable to the core <NUM> of each full reel <NUM> supported by the spindle <NUM>, for determining the push of the core <NUM> actuated by the pushing device <NUM>.

In practice, the pushing device <NUM> moves the core <NUM> by means of the separator <NUM>.

In the light of the foregoing, the pushing device <NUM> is configured to:.

Advantageously the grippers <NUM>, by gripping the portions 2b of the initial flap 2a, determine the tensioning of the central portion 2c of the latter and cause such central portion 2c to be kept tensioned at least during the movement of the grippers <NUM> from the retracted position to the advanced position, in particular until the grippers <NUM> release the initial flap 2a.

More in particular, the grippers <NUM> are configured to receive between them, in the advanced position, the gripper <NUM> of the splicing device of the feeding unit <NUM> for delivering the tensioned central portion 2c of the initial flap 2a to such gripper <NUM>.

Thanks to the above-described configuration, the reel <NUM> is transferred from the vehicle <NUM> to the feeding unit <NUM> (i.e. the reel <NUM> change is carried out) so that the splicing device can receive and grip the initial flap 2a conveniently tensioned in a nominal manner automatically and without the need of the intervention of any operator.

This results in an increase in the production speed, in a minimisation of errors possibly made by the operator and in a reduction in the risk of accidents of the latter and, therefore, in an improvement of the safety conditions of the assembly <NUM>.

Advantageously, the system <NUM> also comprises an unwinding device <NUM> configured to separate the initial flap 2a from the reel <NUM> supported by the spindle <NUM> and to unwind it along the unwinding path T for feeding it to the gripping member <NUM>.

According to a non-limiting embodiment illustrated in <FIG>, the unwinding device comprises a counter-roller <NUM> associated with the spindle <NUM> and movable (in particular controllable by means of the aforementioned control unit) between an open configuration (<FIG>), in which it is spaced apart from the spindle <NUM> and from the reel <NUM> supported, in use, by the latter, and a closed configuration (<FIG>) in which it is contact-pressed (pushed) against such reel <NUM>.

Furthermore, the counter-roller <NUM> is actuatable in rotation (<FIG>) for determining a rotation of the reel <NUM> about the spindle <NUM> and causing the separation of the initial flap 2a from the reel <NUM> and the unwinding of the initial flap 2a along the unwinding path T towards the gripping member <NUM>, i.e. towards the grippers <NUM>.

Alternatively or additionally, the unwinding device comprises an electric motor configured to control the rotation of the spindle <NUM>.

In some non-limiting cases, the unwinding device comprises an opening element, configured to cut or remove an adhesive tape which constrains the flap 2a to the rest of the reel <NUM>.

Conveniently, the system <NUM> further comprises a series of deviating members <NUM> preferably carried by the separator <NUM> and configured to guide the initial flap 2a unwinding along the path T.

Thanks to such configuration, the need for the intervention of the operator is further reduced, who only has to limit himself/herself to loading the reel <NUM> on the spindle <NUM>. In this manner, the production speed within the assembly <NUM> is increased and the risk of errors and accidents is reduced, all in a simple and cost-effective manner.

In an embodiment, also the withdrawing of the reel <NUM> from the storage or receiving station of the assembly <NUM> takes place in an automated manner, in particular, the storage station comprises automatic warehouses.

According to some non-limiting embodiments, the storage or receiving station is arranged at a machine upstream in the production chain of the electrical energy storage devices. In particular, the storage or receiving station corresponds to a station in which the reel <NUM> is completed. In these cases, therefore, the reel <NUM> is transported directly by a machine that winds it to one that unwinds it.

In the non-limiting example described and illustrated herein, the system <NUM> comprises two support spindles <NUM>, both extending cantilevered from the upright <NUM>. In other words, the vehicle <NUM> carries two support spindles <NUM>.

More precisely, the vehicle <NUM> includes a rotatable plate <NUM> mounted in a movable manner to the upright <NUM> and to which the spindles <NUM> are fixed so as to extend cantilevered therefrom.

In order to carry out the reel change, the plate <NUM> is movable, at the change station (i.e. conveniently when the vehicle <NUM> is in the change station), between:.

In particular, the rotatable plate <NUM> is fixed to the upright <NUM> in a rotatable manner about a rotation axis A, preferably horizontal (perpendicular to the upright <NUM>).

Advantageously, the gripping member <NUM> comprises at least one gripper <NUM> for each spindle <NUM>.

In particular, the gripping member <NUM> comprises a pair of grippers <NUM> for each spindle <NUM>, which operate in accordance with what described above.

The operation of the system <NUM> of reel change implemented according to the present invention will be described in the following, with particular reference to <FIG> and to an initial condition in which the vehicle <NUM> has withdrawn a full reel <NUM> to be fed to the feeding unit <NUM> for carrying out a reel change. In particular, one of the two spindles <NUM> carries the full reel <NUM> whereas the other one is free (empty) while waiting to receive the core <NUM> of the exhausted reel <NUM>.

In such condition, the control unit controls, on the basis of the data received from the sensors, the movement of the vehicle <NUM> along the pre-established trajectory from the storage or receiving station to the change station (<FIG>).

Once such position has been reached, the vehicle <NUM> advances for determining the coupling of the empty spindle <NUM> to the spindle <NUM> of the feeding unit <NUM> which supports the core <NUM> of the exhausted reel <NUM> to be changed (<FIG>). Conveniently, the feeding unit <NUM> includes a pushing device <NUM>, preferably one for each spindle <NUM> and substantially of the same type of the pushing device <NUM>, configured to move the core <NUM> supported by the spindle <NUM> towards the spindle <NUM> (shape) coupled to the latter (<FIG>).

In some non-limiting cases not illustrated, the pushing device <NUM> is instead supported by the vehicle <NUM>. In such manner, this prevents modifying to such regard the feeding unit <NUM>.

Once the movement of the core <NUM> has been carried out, the vehicle <NUM> spaces apart from the feeding unit <NUM> for decoupling the spindle <NUM> from the spindle <NUM> (<FIG>), thus the control unit controls the rotation of the rotatable plate <NUM>, so that the spindle <NUM> supporting the full reel <NUM> takes the place of the spindle <NUM> supporting the core <NUM> of the exhausted reel <NUM> and faces the spindle <NUM> (<FIG>). Contextually or previously, for example, the counter-roller <NUM> determines the separation and unwinding of the initial flap 2a along the unwinding path T and the relative grippers <NUM> grip the initial flap 2a (<FIG>). In such condition, the initial flap 2a is tensioned, more in particular the central portion 2c is tensioned, still more in particular, such portion is kept tensioned until the grippers <NUM> deliver the flap 2a to the gripper <NUM> of the splicing device.

At this point, the vehicle <NUM> is controlled for moving close again to the feeding unit <NUM>, so as to determine the coupling of the spindle <NUM> supporting the full reel <NUM> to the spindle <NUM> (<FIG>). The central portion 2c is always kept tensioned.

Then, the pushing device <NUM> is actuated and the core <NUM> of the full reel <NUM> (and therefore the latter) is thus transferred from the spindle <NUM> to the spindle <NUM>. Contextually, the grippers <NUM> are moved from the retracted position to the extracted position (<FIG>).

In such position, the gripper <NUM> of the splicing device is received between the two grippers <NUM> and grips the initial flap 2a at the central portion 2c, which, as specified above, is kept tensioned during such operation.

The delivery of the full reel <NUM> is at this point accomplished, as well as the delivery of the initial flap 2a to the splicing device. The vehicle <NUM> can thus be decoupled from the feeding unit <NUM> (<FIG>).

<FIG> shows an alternative embodiment of the present invention.

According to such embodiment, the system <NUM> comprises the two spindles <NUM>, the rotatable plate <NUM> and a gripping member <NUM>' which differs from the gripping member <NUM> described above only with regard to the following, it being understood that, with the exception of what expressly indicated, the structure and operation of the system <NUM> are identical to those described in the foregoing.

In particular, the gripping member <NUM>' exactly comprises two grippers <NUM> (and not four as in the previous case) selectively associable with the first spindle <NUM> or with the second spindle <NUM> for gripping the initial flap 2a at the portions 2b spaced apart along the unwinding path T for keeping the central portion 2c tensioned. Advantageously, the two grippers <NUM> are arranged (in particular mounted) on the rotatable plate <NUM> spaced apart from one another and aligned along a straight line B lying on the plate <NUM>, orthogonal to the rotation axis A and intersecting the rotation axis A, and the unwinding path T extends along the straight line B (<FIG>).

Preferably, the rotatable plate <NUM> has a circular shape and the straight line B defines a diameter of the rotatable plate <NUM>. The two spindles <NUM> are arranged on opposite sides of the straight line B and the grippers <NUM> are arranged along the diameter of the plate <NUM>, thus intersecting the rotation centre (rotation axis A) of the plate <NUM>.

In an alternative embodiment, the plate <NUM> has a whatsoever different shape (rectangular, oval, triangular, etc.. ), but the straight line B is always arranged so as to lie on the plate <NUM>, intersecting the rotation axis A and orthogonal to the latter.

Furthermore, the spindles <NUM> are arranged at the same distance from the straight line B, thus defining an antisymmetric configuration with respect to the straight line B.

Thanks to such configuration, it is possible to grip the initial flap 2a in two spaced apart points (the portions 2b), thus ensuring the tensioning of the central portion 2c, and at the same time limiting the total number of components (two grippers <NUM> instead of <NUM>) and, therefore, simplifying the architecture and reducing the total costs.

In the light of the foregoing, it is clear that the system <NUM> allows implementing a method for replacing a reel <NUM> of material for the production of electrical energy storage devices, the method comprising the steps of:.

Advantageously, the gripping step is carried out by means of at least one gripper <NUM> and the transferring step comprises moving the gripper <NUM> from a retracted position, in which it grips the initial flap 2a and determines a (places it in) tension thereof, to an advanced position, in which it delivers the tensioned initial flap 2a to the feeding unit <NUM>.

Advantageously, the gripping step comprises gripping the initial flap 2a at the portions 2b spaced apart from one another along the unwinding path T and the tensioning step comprises tensioning the central portion 2c of the initial flap 2a compressed between the two gripped portions 2b.

By examining the characteristics of the system <NUM> and of the method provided according to the present invention, the advantages that they allow obtaining are evident.

In particular, the system <NUM> and the method according to the present invention allow determining an increase in the production speed within the assembly <NUM>, a minimisation of errors possibly made by the operator and a reduction in the risk of accidents of the latter and, therefore, an improvement of the safety conditions of the assembly <NUM>.

Furthermore, the presence of the counter-roller <NUM> for automatically unwinding the initial flap 2a and delivering it to the grippers <NUM> determines a further accentuation of the aforementioned advantages.

Finally, in the event the system <NUM> comprises the gripping member <NUM>', the aforementioned advantages are achieved limiting at the same time the total number of components and, therefore, simplifying the architecture and reducing the total costs.

Claim 1:
System (<NUM>) for replacing a reel (<NUM>) of material for the production of electrical energy storage devices, the system (<NUM>) comprising:
- a vehicle (<NUM>), preferably a self-driving vehicle, for transporting a reel (<NUM>) from a storage or receiving station to a change station;
the system (<NUM>) being characterized by further comprising:
- at least one support shaft or spindle (<NUM>) carried by the vehicle (<NUM>) and configured to support the reel (<NUM>) and to transfer it, at the change station, to a feeding unit (<NUM>) of an automatic machine (<NUM>) for the production of the electrical energy storage devices; and
- a gripping member (<NUM>; <NUM>') carried by the vehicle (<NUM>) and comprising at least one gripper (<NUM>) configured to receive and grip an initial flap (2a) of the reel (<NUM>) supported by the support spindle (<NUM>) and to keep such initial flap (2a) tensioned along an unwinding path (T) of the same.