CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from Italian Patent Application No. 102017000117582 filed on 18/10/2017, the disclosure of which is incorporated by reference.

TECHNICAL FIELD

The present invention lies in the technical field relating to aerosol-generating devices. In particular, the present invention relates to a cutting unit for the cutting of a substrate band for an aerosol-generating device. Moreover, the present invention relates to a cutting assembly comprising said cutting unit.

PRIOR ART

As is known, aerosol-generating devices are made up of several components which must be appropriately assembled together. In particular, an aerosol-generating device can comprise: a cartridge containing a flavoured liquid; a substrate made of a flexible (non- rigid) material, which is capable of carrying the liquid by capillary action; an atomizer which heats the liquid carried by the substrate to generate aerosols; a rechargeable battery powering the atomizer.

The substrate, which has very small dimensions, is obtained starting from a substrate band that must be suitably cut and then assembled in the cartridge. Currently, the cutting of the substrate band is performed manually. This leads to inaccuracies in the formation of the substrate and high production times.

Moreover, the production of aerosol-generating devices and related cartridges is becoming increasingly automated; consequently, the manual production of the substrate makes it complex to transfer substrates (small substrates made of flexible material) to the component assembly stations of the aerosol-generating device.

Patent application WO2015165815A1 discloses a method for manufacturing a container provided with a heater for an aerosol-generating device.

Patent US6435067B 1 discloses a device for separating thermoformed articles from a continuous band of plastic or expanded material.

Patent application WO2012152798A1 describes a device for cutting a rod from a continuous band of porous material and then applying the rod to a filter component. DESCRIPTION OF THE INVENTION The object of the present invention is to overcome the aforesaid problems. This object is achieved by means of a cutting unit for the cutting of a substrate band for an aerosol- generating device and a related cutting assembly in accordance with the appended claims. Advantageously, the present invention allows a substrate band made of a flexible material to be cut in a quick and precise manner. Furthermore, the substrate portions exiting the cutting unit are arranged and oriented so as to be transferred to a successive assembly unit of the aerosol-generating device.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described with reference to the accompanying drawings, which illustrate a non-limiting embodiment thereof, in which:

- Figures 1 and 2 are respective perspective views of an embodiment of the cutting unit according to the present invention;

- Figure 3 is an enlarged detail of the cutting unit of Figure 1 in which the substrate band has been omitted to better highlight other parts of the cutting unit;

- Figures 4-6 are enlarged cross-sectional views of the cutting unit of Figure 2, each in a respective operating position of the cutting head 4;

- Figure 7 is a perspective view of a cutting assembly according to the present invention. PREFERRED EMBODIMENTS OF THE INVENTION

With reference to the accompanying figures, reference numeral 1 designates a cutting unit for the cutting of a substrate band for an aero sol -generating device and reference numeral 100 designates a cutting assembly comprising the aforesaid cutting unit 1. The expression "substrate band", indicated with reference numeral 2 in the accompanying figures, is intended to mean a band made of a material suitable for carrying a liquid by capillary action. In this regard, the substrate band may be made of any material suitable for this purpose. For example, the substrate band 2 may have a spongy or fibrous structure. In any case, the substrate band 2 is flexible (i.e. it is not rigid). For example, the substrate band 2 may be made of a material comprising cellulose or polymeric material. For example, the substrate band 2 may be made of a material comprising wadding or paper or a super absorbent polymer. In accordance with a preferred embodiment, the substrate band 2 is made of cellulose acetate.

The substrate band 2 has a longitudinally-extending axis X. It is preferably unwound from a bobbin of substrate band.

One embodiment of the cutting unit 1 according to the present invention will be described hereinafter with reference to the accompanying drawings. The cutting unit 1 comprises feed means 3 (Figure 7) for feeding the substrate band 2 along a feed direction Y parallel to the extension axis X.

These feed means 3 may comprise several pulleys 30 whose rotation causes the feeding of the substrate band 2. It is understood that this is only a preferred embodiment, therefore these feed means 3 can be made with any other means known to a person skilled in the art.

With particular reference to the illustrated embodiment, the cutting unit 1 comprises three cutting heads 4, each comprising a cutting edge 40 having a closed profile for cutting a substrate portion 20 from the substrate band 2.

The three cutting heads 4 are movable in a movement direction Z transversal (preferably orthogonal) to the feed direction Y of the substrate band 2, between a cutting position, in which they cut the respective substrate portion 20, and a release position A (Figure 6), in which they release the respective substrate portion 20.

In particular, with reference to the figures, the substrate band 2 comprises at least one horizontal segment at which the substrate portions 20 are formed; the movement direction Z of the cutting heads 4 is vertical (i.e. orthogonal to the horizontal segment of the substrate band 2).

The cutting unit 1 further comprises conveying means 5, which are arranged and shaped so as to receive the substrate portion 20 from each cutting head 4 when the cutting head 4 is in the release position A, and convey the substrate portions 20 towards an output section 6.

Advantageously, the proposed cutting unit 1 allows the substrate band 2 to be cut in a quick and precise manner. Furthermore, the substrate portions 20, through the conveying means 5, arrive at the output section 6 of the cutting unit 1: the substrate portions 20 are advantageously arranged so as to be transferred to a component assembly unit of the aerosol-generating device.

With particular reference to the accompanying figures, each cutting head 4 is movable in a movement direction Z parallel to the movement direction Z of the other cutting heads 4. In addition, the cutting heads 4 are moved synchronously with each other.

In addition, still in accordance with the embodiment of the cutting unit 1 shown in the figures, the three cutting heads 4 are mutually aligned in a line orthogonal to the feed direction Y of the substrate band 2.

It is to be understood that the cutting unit 1 may comprise a different number of cutting heads 4 without thereby departing from the scope of protection of the invention. For example, the cutting unit 1 could comprise a single cutting head 4 or more than three cutting heads 4. In addition, the cutting heads 4 could be arranged according to different patterns with respect to the illustrated one. For example, according to an embodiment, not shown, the cutting unit 1 could comprise nine cutting heads 4 arranged in a three -by-three array.

The cutting heads 4 can be shaped like tubular elements with the cutting edge 40 at one end thereof.

The substrate portion 20 usually has the shape of a small disk or a quadrilateral with an area ranging between 20 mm ² and 30 mm ² .

With reference to the figures, the cutting edge 40 is circular. It may have a radius of between 2 mm and 3.5 mm. Alternatively, the cutting edge 40 could be a quadrilateral (for example, a square or a rectangle). It could have sides of length between 4 mm and 6 mm.

With particular reference to Figure 3, the cutting unit 1 may comprise a support plate 7 for supporting the substrate band 2. It is preferably arranged in a horizontal plane (orthogonal to the movement direction Z).

This support plate 7 comprises three through holes 70, each aligned with a respective cutting head 4 (i.e. aligned with the movement direction Z of the respective cutting head 4) and sized so as to be passed through by said respective cutting head 4. It is understood that the number of through holes 70 is equal to the number of cutting heads 4.

The support plate 7 is arranged between the substrate band 2 and the conveying means 5 so that the cutting head 4 passes through the through hole 70 when it is moved along the movement direction Z. In particular, each cutting head 4 passes through the corresponding through hole 70 when it is moved from the cutting position to the release position A, and vice versa.

The support plate 7 ensures a precise cut of the substrate band 2: advantageously, the substrate portion 20 obtained has a sharp edge.

Still with reference to Figure 3, the cross section of each of the through holes 70 has a profile with the same shape as the closed profile of the cutting edge 40. Advantageously, the support plate 7 acts in opposition to the cutting heads 4.

In other words, each through hole 70 is defined by a side wall having a cross section defining a closed profile identical to the closed profile of the cutting edge 40.

The cutting heads 4 are preferably suction heads. Advantageously, when moved from the cutting position to the release position A, they retain the substrate portion 20 so as to ensure a correct orientation of the substrate portion 20 on the conveying means 5 (Figure 5).

The conveying means 5 may comprise a conveyor belt 50 (or a carrying strap) comprising a release segment 50a at which it receives the substrate portion 20 from the cutting head 4. The release segment 50a extends in a plane orthogonal to the movement direction Z of the cutting head 4 (the release segment 50a is preferably horizontal).

In particular, the conveyor belt 50 is a closed-loop belt.

The conveying means 5 are arranged below the support plate 7. In addition, the release segment 50a is in a plane parallel to the substrate band 2.

The conveyor belt 50 is preferably of the suction type (i.e. it is subjected to a suction source, not shown). In particular, with reference to the attached figure, the conveyor belt 50 comprises a plurality of suction holes 51 mutually aligned along the extension of the conveyor belt 50. In detail, when the three cutting heads 4 are in the release position A, three suction holes 51 of the conveyor belt 50 are each aligned with a respective cutting head 4 (i.e. with the movement direction Z of the corresponding cutting head 4).

Therefore, each substrate portion 20 obtained is released at a suction hole 51 of the conveyor belt 50. Advantageously, the correct positioning of the substrate portions 20 on the conveyor belt 50 is ensured during their conveyance towards the output section 6. It is understood that the conveyor belt 50 may comprise a different number of suction holes 51 with respect to those illustrated. Moreover, said suction holes 51 could be arranged in a different manner from that shown herein without thereby departing from the scope of protection of the invention.

Alternatively to what has been described previously, the conveyor belt 50 can be made of an air-permeable material (and therefore may not necessarily require the presence of the suction holes 51), or it may have a mesh-like conformation.

With particular reference to Figure 1, the conveying means 5 convey the substrate portions 20 in a plane parallel to the substrate band 2 and in a conveying direction W transversal (in particular, orthogonal) to the feed direction Y of the substrate band 2. Advantageously, such an arrangement of the conveying means 5 allows particularly small sizing of the cutting unit 1.

The cutting unit 1 may comprise, downstream of the cutting heads 4, means for discarding the substrate band 2. These discarding means can rewind the waste of the substrate band 2 back into a bobbin or can shred it.

A working cycle of the cutting unit 1 is described below with reference to figures 4-6. With reference to Figure 4, the substrate band 2 is stationary on the support plate 7 and three suction holes 51 of the conveyor belt 50 are each aligned with a respective cutting head 4 (and therefore are aligned with the through holes 70 of the support plate 7); the conveyor belt 50 is also stationary. The three cutting heads 4 face the substrate band 2; in detail, the corresponding cutting edge 40 is arranged near the substrate band 2. At this point, the three cutting heads 4 are moved along the movement direction Z until each substrate portion 20 is contacted and cut (cutting position of the cutting heads 4). Simultaneously with the cutting of the substrate band 2, the suction from the cutting head 4 is active so that each cutting head 4 will retain the respective substrate portion 20. Subsequent to the cutting, with reference to Figure 5, the cutting heads 4 continue to move along the movement direction Z, each passing through a respective through hole 70 of the support plate 7 and retaining the substrate portion 20 by suction. The substrate band 2 and the conveying means 5 are always stationary. Thereafter, with reference to Figure 6, the cutting heads 4 reach the release position B and release the substrate portions 20 at corresponding suction holes 51 of the conveyor belt 50: in this phase, the suction from the cutting heads 4 is stopped and the suction from the suction holes 51 is activated (alternatively, the suction holes 51 could have a greater suction power than that of the cutting heads 4). Lastly, the feed means 3 are activated so as to cause a predetermined portion of the substrate band 2 to be fed along the feed direction Y, the conveying means 5 are moved so as to move the substrate portions 20 towards the output section 6 and align three further suction holes 51 with the cutting heads 4. Moreover, the cutting heads 4 are further moved along the movement direction Z to bring them back to the initial position of Figure 4. Subsequently, the cutting unit 1 resumes the working cycle.

A cutting assembly 100 for cutting a substrate band 2 for an aerosol-generating device - which is also an object of the present invention - is described below with reference to Figure 7.

The cutting assembly 100 comprises: a cutting unit 1 in accordance with one of the aforesaid embodiments described above; an assembly unit 8 for assembling components (for example cartridges) of the aerosol-generating device; transferring means 9 arranged so as to transfer the substrate portion 20 from the output section 6 of the cutting unit 1 to the assembly unit 8.

This cutting assembly 100 allows easy and automatic transfer of the substrate portions 20 from the cutting unit 1 to an assembly unit 8.

The transferring means 9 may be of the pick and place type. In detail, these transferring means 9 may comprise a pick and place head 90, which is movable between a pick-up position in which it picks up (e.g. by suction) a substrate portion 20 from the output section 6 of the cutting unit 1, and a release position in which it places said substrate portion 20 at the assembly unit 8 (arranged downstream of the cutting unit 1).