WRAPPING MACHINE FOR CONFECTIONERY PRODUCTS

Technical field

This invention relates to a wrapping machine for confectionery products. Specifically, this invention can be applied to the wrapping of confectionery products such as, for instance, sweets, chocolates, and the like, to which this description will hereinafter refer but without thereby limiting the scope of the invention.

Background art

There are prior art wrapping machines for wrapping confectionery products comprising a transfer drum for transferring a series of products to a wrapping device.

In general, the wrapping device comprises a first and a second folding roller which are at a tangent to one another at a transfer station for transferring the products where the products pass from the first to the second folding roller.

In particular, the first folding roller couples a sheet of wrapping material around the respective product and the second folding roller wraps the sheet of wrapping materia! according to a tubular wrapper configuration which is subsequently folded according to a predetermined wrapping shape.

In prior art wrapping machines the type of products to be wrapped greatly influences the machine architecture, since the products to be wrapped must be fed to the wrapping device with a predetermined orientation.

Consequently, switching from wrapping confectionery products which are spherical or have an elongate parallelepiped shape, whose wrapping shape is usually of the "double-twist" type, to wrapping products which are frustoconical, whose wrapping shape is usually of the single "top-twist" type, requires machine reconfiguration, substituting at least one of the two folding rollers of the wrapping device.

Substitution of a folding roller is a rather onerous operation, since lengthy downtimes are involved, which are converted into costs for lost production, the use of dedicated equipment, given the considerable weight of each folding roller, and the use of qualified personnel suitable for operating on the machine.

Disclosure of the invention

The aim of this invention is to provide a wrapping machine for confectionery products which overcomes the above-mentioned disadvantages, that is to say, which allows correct orientation of the confectionery products to be wrapped upstream of the wrapping device in such a way that, if the type of product is changed, there is no need to substitute any of the folding rollers on the machine.

In order to obtain good quality final wrapping of the products, it is also necessary to always guarantee perfect mutual positioning of every single product and the related wrapping material.

The technical purpose specified and the aims indicated are achieved by a machine and a method having the features described in the respective independent claims 1 and 8.

Brief description of drawings

Further features and advantages of this invention are more apparent in the description below, with reference to a preferred, non-limiting embodiment of a machine as illustrated in the accompanying drawings, in which:

- Figure 1 is a schematic front view of the machine according to the invention;

- Figure 2 is an enlarged perspective view of a first detail of the machine of Figure 1 ;

- Figure 3 is a side view of the first detail shown in Figure 2; - Figure 4 is an enlarged perspective view of the first detail shown in Figure 2 in a further operating step of it;

- Figure 5 is an enlarged perspective view of a second detail of the machine of Figure 1 ;

- Figure 6 is a plan view of the second detail shown in Figure 5.

Detailed description of preferred embodiments of the invention

With reference to Figure 1 , the numeral 1 denotes in its entirety a wrapping machine for confectionery products 2.

In the embodiment described, reference will be made to confectionery products 2 which mainly extend along a vertical axis V.

In particular, the products 2 have a substantially frustoconical shape, having a flat resting base 3.

The products 2 comprise a top end 3b, opposite to the resting base 3. The frustoconical shape of the confectionery products 2 makes them particularly suitable for being wrapped with a type of wrapping shape called "boero", that is to say, a wrapping shape which has a single top "twist", positioned along the vertical axis V on the opposite side to the resting base 3 of the product 2,

The machine 1 comprises a vertical wail 4 which supports a plurality of conveyor rollers 26, 12, 19 for conveying the products 2 with their respective axes of rotation 26a, 12a, 19a horizontal, perpendicular to the wall 4.

The machine 1 comprises a feed device 5 for feeding a series of confectionery products 2 in a predetermined direction D of feed.

In particular, the series of confectionery products 2 is an orderly series. Alternatively, the series may be a continuous row without a gap between one product and the next, or a random series.

Furthermore, the series may be a random series of products which are gripped after being identified by suitable sensors.

The feed device 5 comprises a conveyor belt 6 on which the confectionery products 2 are fed with their vertical axis V orthogonal to the direction D of feed of the conveyor belt 6,

More precisely, the products 2 are conveyed with their resting base 3 in contact with the belt 6.

The feed device 5 conveys the orderly series of products 2 towards a feed station 7, where the products 2 are picked up for wrapping.

The machine 1 comprises a wrapping device 8 which comprises a first and a second wrapping drum 9 and 10 which are substantially at a tangent to one another at a transfer station 11 for transferring the products 2, in such a way that the second drum 10 receives the products 2 from the first drum 9.

The wrapping device 8 comprises a loading station 17, where products are fed to the first drum 9, and an outfeed station 18, where the second drum

10 unloads the wrapped products 2.

The first drum 9 comprises the first conveyor roller 12 which acts as the first folding roller 12 comprising a plurality of first jaw elements 13.

The first jaw elements 13 are evenly distributed along the cylindrical outer surface of the first roller 12, parallel with the vertical wall 4.

The second wrapping drum 10 comprises the second conveyor roller 19 which acts as the second folding roller 19 comprising a plurality of second jaw elements 20.

The second jaw elements 20 are evenly distributed along the cylindrical outer surface of the second folding roller 19, parallel with the vertical wall 4.

In the embodiment illustrated in Figure 1 , the first folding roller 12 rotates clockwise and the second folding roller 19 rotates anti-clockwise.

The first wrapping drum 9 comprises a feed device 14 for feeding sheets of wrapping material 15, facing the cylindrical outer periphery of the first folding roller 12.

Positioned downstream of the feed device 14, according to the direction of rotation of the first folding roller 12, there is a fixed curved panel 16 also facing the cylindrical outer periphery of the first roller 12.

The feed device 14 and the fixed curved panel 16 are both positioned between the loading station 17 for loading the first wrapping drum 9 and the transfer station 11.

A first mobile folder 21 and a fixed folder 22, positioned downstream of the mobile folder 21 , with reference to the direction of rotation of the second folding roller 19, are positioned facing the cylindrical outer surface of the second folding roller 19.

Positioned at the outfeed of the fixed folder 22, there is a second folder 23 designed to make the twist characteristic of the "top twist" wrapping shape, completing the wrapping of the product 2.

In use, to centre the products 2 to be wrapped on the respective sheet of wrapping material 15 and to guarantee successful production of the wrapping shape, the products 2 must be fed to the wrapping device 8 with their vertical axis V positioned perpendicularly to the vertical wall 4, along a direction parallel with the axes of rotation 12a and 19a of the first and second folding rollers 12 and 19.

In other words, the products 2 are fed to the first wrapping drum 9 with their resting base 3 parallel with and facing the vertical wall 4.

The first folding roller 12 receives the products 2 at the loading station 7 by means of the first jaw elements 13.

Each first jaw element 13 grips a respective product 2 at the resting base 3 and the free end 3b opposite to the base 3.

At this point, during rotation of the first folding roller 12, the first jaw elements 13, holding the respective product 2, pick up, by means of a further gripper 24, a sheet of wrapping material 15 from the feed device 14, coupling it with the product 2.

A first portion of the sheet 15 is clamped against the product 2 and a second portion is left projecting radially outwards from the first folding roller 12.

Then, after the rotation of the first roller 12, the second portion of the sheet of wrapping material 15 is folded into an L shape by interference with the fixed curved panel 16.

At this point, once the products 2 come out of the fixed curved panel 16, the second folding roller 9 picks up the products 2 with the respective sheet of wrapping material 15 using the second jaw elements 20.

Each second jaw element 20 grips a respective product 2 with the respective sheet of wrapping material 15, folding the sheet 15 in a U shape around the product 2, with two side flaps projecting outwards from the second folding roller 19.

During the rotation of the second folding roller 9, the products 2 are fed to the first mobile folder 21 which folds down one projecting flap of the sheet of wrapping material 15, positioned upstream of the other projecting flap, relative to the direction of rotation of the second roller 19.

Then, the product 2 is fed towards the fixed folder 22 which folds down the remaining projecting flap, forming a tubular wrapper around the product 2. Moreover, the flaps projecting beyond the base 3 are folded onto the base 3, the base itself acting as a contact element for the folders 21 and 22. The tubular wrapper has one open free end, opposite to the resting base 3, where the wrapper closing bow is created by the second folder 23, in the case of a "top twist" type of wrapper.

At this point, at the outfeed station 18, the second folding roller 19 releases the products 2 which have been wrapped according to the required wrapping shape.

The machine 1 comprises a transfer drum 25 for transferring the products 2 from the feed station 7 to the loading station 17 of the wrapping device 8.

The transfer drum 25 comprises the conveyor roller 26 which acts as a transfer roller 26 rotating about its own horizontal axis 26a of rotation.

The transfer roller 26 comprises a plurality of pickup units 27, evenly distributed along the outer circumference of the transfer roller 26.

The pickup units 27 extend outwards from the outer cylindrical surface of the transfer roller 26 and are positioned facing an end surface of the roller 26, on the opposite side to the vertical wall 4.

As schematically illustrated in Figures 2 to 6, each pickup unit 27 comprises a head body 28 and a main body 29 supported by the head body 28.

The head body 28 is connected to the transfer roller 26 and rotates together with it.

The main body 29 of each pickup unit 27 is rotatabiy connected to the respective head body 28.

In particular, the main body 29 rotates about its own axis of rotation 29a. The axis of rotation 29a is transversal to the axis 26a of rotation of the transfer roller 26 and is positioned along a direction which is radial relative to the roller 26,

Cam transmission means, not illustrated, drive the rotation of the main body 29 about its own axis 29a, during the rotation of the transfer roller 26. More precisely, during the rotation of the transfer roller 26 from the feed station 7 to the loading station 1 the main body 29 of each pickup unit 27 rotates 90° about its own axis 29a.

The main body 29 of each pickup unit 27 comprises a pair 30 of grippers 31 able to move towards and away from one another.

Each pair 30 of grippers 31 comprises at the free end a respective pair 32 of grabber elements 33 for gripping the products 2.

More precisely, each gripper 31 is equipped with its own grabber element

33,

Said grabber elements 33 are in the form of plates suitably shaped to guarantee an effective hold on the products 2.

The grabber elements 33 of each pair 30 of grippers 31 are free to rotate about an axis of rotation 34.

The axis of rotation 34 is orthogonal to the axis of rotation 29a of the main body 29.

Therefore, each pickup unit 27, as well as rotating about the axis 26a of the transfer roller 26, has a first and a second axis of rotation 29a and 34. The first axis of rotation 29a is the axis of rotation of the main body 29 and the second axis of rotation 34 is the axis of rotation of the grabber elements 33.

The first axis of rotation 29a is transversal to the axis of rotation 26a of the transfer roller 26 and extends along a direction which is radial relative to the transfer roller 26.

The second axis 34 of rotation is orthogonal to the first axis of rotation 29a.

During the rotation of the transfer roller 26, from the feed station 7 to the loading station 17, the rotation of the main body 29 about the first axis of rotation 29a and the rotation of the pair 32 of grabber elements 33 about the second axis of rotation 34 occur simultaneously.

More precisely, the rotation of the main body 29 about the first axis of rotation 29a drives the rotation of the pair 32 of grabber elements 33 about the second axis of rotation 34.

In particular, from the feed station 7 to the loading station 17, the pair 32 of grabber elements 33 rotate 90° about the second axis of rotation 34.

Each pickup unit 27 comprises crank means 35 associated with each pair 32 of grabber elements 33.

During the rotation of the main body 29 about the first axis of rotation 29a, the crank means 35 drive the rotation of the pair 32 of grabber elements 33 about the second axis of rotation 34.

Each pickup unit 27 comprises a single supporting element 36 for the crank means 35 which is connected to the main body 29.

The supporting element 36 is rigidly connected to the main body 29 in such a way that the rotation of the main body 29 about its own axis 29a drives the rotation of the supporting element 36,

The crank means 35 comprise a series of arms 38, 39 and 40, hinged to one another, which connect the supporting element 36 to a respective grabber element 33. In particular, the crank means 35 comprise a first arm 38, connected to the supporting element 36, a second arm 39, connected to the first arm 38, and a third arm 40, connected to the second arm 39 and to the respective grabber element 33.

The series of arms 38, 39 and 40 forms an articulated system with a driver, the first arm 38, and a follower, the third arm 39.

The simultaneous rotation of the products 2, conveyed by the respective pickup unit 27, about the first and the second axes of rotation 29a and 34, allows the products 2 to be oriented at the loading station 17 of the wrapping device 8, in such a way that the resting base 3 is facing the vertical wall 4 and the vertical axis V is parallel with the axis of rotation 26a of the transfer roller 26.

In use, at the feed station 7, the pair 30 of grippers 31 and the respective grabber elements 33 are positioned according to a direction transversal to the direction D of feed of the orderly series of products 2.

The grippers 31 move towards one another until the respective grabber elements 33 grip the respective product 2.

In particular, the grabber elements 33 engage the product 2 at its side surface, leaving the resting base 3 and the head end 3b opposite to it free. It should be noticed that, at the feed station 7, the vertical axis V of the product 2 is positioned along a direction parallel with the first axis of rotation 29a of the main body 29 of the respective pickup unit 27.

Once the pickup unit 27 has received the respective product 2, the transfer roller 26 conveys it from the feed station 7 to the loading station 17.

During the rotation of the transfer roller 26, which in the embodiment illustrated is anticlockwise, the main body 29 is driven to rotate about its own axis 29a.

In particular, the main body 29 of each pickup unit 27 rotates about the first axis 29a in a clockwise direction.

At this point, the supporting element 36, securely connected to the main body 29, is also driven to rotate about the first axis 29a. In turn, the supporting element 36 drives the rotation of one of the ends 38a of the first arms 38 of the crank means 35.

The first arms 38 move the respective second arms 39 which, in turn, drive the respective third arms 40 which, oscillating about the second axis 34 of rotation, cause the respective grabber elements 33 to rotate about the second axis 34.

In particular, the grabber elements 33 rotate about the second axis of rotation 34 in a clockwise direction.

The products 2 held by the grippers 31 of the respective pickup unit 27 therefore rotate relative to the axis of rotation 26a of the transfer roller 26, since they are conveyed from the feed station 7 to the loading station 17, and relative to the first and the second axes of rotation 29a and 34 of each pickup unit 27.

Once each pickup unit 27 reaches the loading station 7 of the wrapping device 8, the main body 29 has rotated 90° about the first axis of rotation 29a and the pair 32 of grabber elements 33 has rotated 90° about the second axis of rotation 34, compared with the starting position they adopted at the feed station 7.

After the simultaneous 90° rotation about the first and second axes 29a and 34, the products 2 are positioned with their vertical axis V orthogonal both to the first and the second axes of rotation 29a and 34, according to a direction parallel with the axis 26a of rotation of the transfer roller 26.

That configuration allows the wrapping device 8 to pick up the products 2 by gripping them at the resting base 3 and the head end 3b opposite to it, guaranteeing optimum centring of the product 2 with the respective sheet of wrapping material 15.

Advantageously, since the pickup units 27 of the transfer drum 25 correctly orient the products 2 to be wrapped by means of the rotation about the first and the second axes 29a and 34, the machine 1 according to this invention is able to wrap confectionery products 2 which have a frustoconical, or spherical or parallelepiped shape. in fact, if the product 2 has a spherical or parallelepiped shape, the simultaneous rotation about the first and second axes 29a and 34 allows the product 2 to be correctly oriented.

in any case, if the products 2 to be wrapped do not require double rotation about the two axes 29a and 34, the machine 1 can simply be reconfigured by substituting only the pickup units 27, avoiding substitution of the first and the second folding rollers 12 and 19.