Description

METHOD AND APPARATUS FOR APPLYING LABELS ON FRUITS AND

VEGETABLE PRODUCTS

Technical field

[0001] The present invention relates to a method and an apparatus for applying labels of fruits and vegetable products and such.

Background art

[0002] It is known that fruits and vegetable products packed for sale are often equipped with a label that indicates their origin. To apply these labels onto the products suitable labelling devices are used, arranged along a packaging line on which the products are fed and moved forward, for instance to be classified one by one according to visual and weight parameters, selectively grouped and packaged in separate packaging units.

[0003] Known labelling devices are for instance illustrated in patents EP 0113256, EP 0879764, EP 1163155. These labelling devices generally provide that the labels are dispensed on strips unrolled by suitable feeding spools while the products are fed in sequence on a conveying line underneath. Each label is taken from the strip and transferred to a labelling member shaping a drum activated revolving around a horizontal axis transversal to the feeding direction of the products. The drum is peripherally equipped with a series of gripping elements of the single labels, activated alternatively between a retracted position for the receipt of the label from the feeding strip and an extracted applying position suitable to produce the adherence of the label onto a portion of the product.

[0004] The patent US 4244763 illustrates a labelling device including an intermediate frame in which the labels are suited to stop before being taken from the respective labelling member. Suitable knurled roller-shaped transfer means carries out the pick-up of the labels from the feeding strip and releases the same labels onto the intermediate frame. This transfer means is suitable to imprint its knurled shape onto the single label, in order to decrease its rigidity and facilitate in this way the subsequent application onto the product.

[0005] A problem pointed out during the cited labelling phase is that a rather relevant portion of labels comes off the product soon after the labelling onto the product itself. This detachment is mainly due to the fact that during the packaging phase the products have, on the external surface, a more or less uniform film of i

moisture, which impedes the firm adhesion of the labels. This film of moisture is generated by the noticeable change in temperature that the products undergo when they are transferred from the cold stores to the packaging line, which is usually at room temperature or is conditioned at an anyway higher temperature.

[0006] The detachment of the labels happens even more for certain types of products that by nature offer a low adhesive capacity, as in the case of kiwis and other similar products. These products are, in fact, coated with an external peel with accentuated hairiness, presenting a very limited adhesive capacity.

[0007] This brings with it the risk that the packages come out of the packaging line with a very exiguous number of products equipped with the label or even without any visible label, since the label itself can be turned towards the internal part of the packaging.

[0008] To remedy this inconvenience, labels are currently applied manually onto the products, in case they are missing, before packaging. The packaging lines have to be constantly supervised by operators, who apply the necessary labels when needed.

[0009] This clearly brings with it a noticeable employment of labour, and also a non- negligible waste of material, because of the labels lost along the packaging line.

Disclosure of the invention

[0010] The aim of the present invention is to overcome the cited drawbacks by devising a method, which enables to effectively carry out the application of labels on fruits and vegetable products, preventing these labels from coming off the products themselves.

[0011] Within this scope it is a further aim of the claimed invention to devise an apparatus for applying labels on fruits and vegetable products of simple conception, of certainly reliable functioning and of versatile use, and also of limited overall dimensions and of relatively economical cost.

[0012] The cited aims are reached, according to the claimed invention, through the method for applying labels on fruits and vegetable products in apparatuses equipped with at least one labelling device arranged along the conveying line of products to label, which is characterized in that it comprises the phases of:

[0013] (a), conveying the products to label in a predetermined position as to the said conveying line;

[0014] (b). performing the localized heating of a surface portion of limited amplitude of

each product, in order to cause the drying of the said portion in an operative area arranged immediately upstream to the said labelling device;

[0015] (c). applying a label onto the said dried surface portion of the product.

Brief description of the drawings

[0016] Description details of the invention will be further evident in the illustrations of a preferred embodiment of the apparatus for applying labels on fruits and vegetable products illustrated in the guideline drawings attached, wherein:

[0017] fig. 1 illustrates a side view of an apparatus for applying labels according to the invention;

[0018] fig. 2 illustrates a side enlarged view of a detail of the claimed apparatus;

[0019] fig. 3 illustrates a front view of the same apparatus.

Best mode for carrying out the invention

[0020] With reference to such figures, 1 refers to the apparatus for applying labels on fruits and vegetables products 2.

[0021] The apparatus 1 is destined to be associated to a conveying line 3 suited to convey the products 2 to label, along a feeding direction A between an entry station 4 and an exit station 5, in which the labelled products 2 are unloaded for the following packaging operations.

[0022] The conveying line 3 is preferably defined by a plurality of parallel rollers 6, arranged transversally to the feeding direction A. In particular, each roller 6 longitudinally shapes a series of conical portions 7 with alternate inclination, in order to conform with the adjacent rollers 6 a plurality of concave seats 8, arranged along feeding lines placed side by side and suited to receive single products 2 according to a predetermined orientation. If, in particular, the products 2 have an elongated shape, as for instance in the case of kiwis, these place themselves in the cited concave seats 8 with the respective longitudinal axis oriented parallel to the axis of the rollers 6. At its ends, each roller 6 is fastened to flexible drive means 9 of chain type, operated by known not illustrated control means.

[0023] At the entry station 4, the apparatus 1 provides for a series of compressed air cleaning members 10, arranged aligned in transversal direction as to the conveying line 3 at the cited lines for feeding the products 2 respectively, arranged side by side and defined by the concave seats 8 of the rollers 6. Each cleaning member 10 includes a blower nozzle 11 connected through ducts 12 to

a feeding circuit of the compressed air through the interposition of a proper electronically controlled valve. The blower nozzles 11 are arranged vertically above the conveying line 3, so that, upon previous operation of the cited electronically controlled valves, the products 2 in process of feeding are hit from above by a jet of compressed air. The blowing action of the blower nozzles 11 is suitable to remove possible dirt particles deposited on the external surface of the products 2.

[0024] To each blower nozzle 11 are associated some sensors 13 of photocell type, suitable to detect the presence of a relative product 2 on the conveying line 3, to transmit proper signals for the activation of the same blower nozzle 11. Usefully, the sensors 13 are carried adjustable on the vertical surface longitudinal to the conveying line 3, in order to allow the adjustment of their position according to the dimensional features of the products 2 in process.

[0025] Downstream to each cleaning member 10 is arranged a heating unit 14 suitable for causing the localized warming of a small surface portion of each product 2.

[0026] The heating unit 14 basically shapes a cylindrical tubular body arranged above the conveying line 3 parallel to the feeding direction A, above a respective row of concave seats 8 of the products 2. This cylindrical body is composed of an external tube 15 frontally closed and provided with a plurality of holes 16 having small diameter, aligned on at least one axial vertical surface on the side of the same tube facing the conveying line 3 (see in particular fig. 2). In fact, the holes 16 are preferably arranged alternate along two side-by-side rows, in order to determine a limited enlargement of the warmed area. Inside the external tube 15 is inserted coaxial an internal tube 17 with smaller external diameter and shorter longitudinal extension, suitable to internally house a heating element 18 preferably with relatively long and narrow shape. The heating element 18, for instance of resistance-type, is suited to be inserted through a closed end of the external tube 15, whereat the heating element 18 is connected to power supplying means of known type. At the opposite end, the external tube 15 is closed through a head 19 equipped with connection means suitable for connecting the internal tube 17 only with an air feeding circuit. Control means of the type of the electronically controlled valves are preferably interposed on this air feeding circuit. Practically, the fed air is suited to flow through the head 19 inside the internal tube 17 in longitudinal direction, to progressively undergo the

warming effect of the heating element 18. Further on the open end of the internal tube 17, the presence of the corresponding closed end of the external tube 15 is suitable for reversing the motion of the heated air along the interspace formed longitudinally between the two tubes 15, 17. The heated air is suitable to progressively flow through the holes 16, to produce localized jets of warm air towards a direction orthogonal to the conveying line 3 underneath.

[0027] The heating units 14 and the corresponding cleaning members 10 are fastened to a frame 20 whose vertical positioning above the conveying line 3 is adjustable through an adjusting device 26 shaping coupling means of the worm screw type that can be manually activated through a control hand-wheel 21.

[0028] Immediately downstream to the heating units 14 is arranged a labelling device 30, in itself known, suitable for applying a label on each product 2 passing through on the conveying line 3 underneath.

[0029] Downstream to the labelling device 30 is usefully provided a roller-shaped presser 22 suitable for exerting an appropriate elastic compression action on each product 2 in the portion involved in the application of the label.

[0030] The presser 22 is constituted by a roller activated revolving around an axis transversal to the feeding direction A, arranged at a preset distance from the conveying line 3 such as to interfere with the upper part of each product 2 in the portion relevant to the application of the label. The roller 22 is preferably coated with an elastically deformable material, for instance spongy, suitable to exert an effective compression action exclusively on the surface portion where the label is applied without damaging or compromising the integrity of the product 2. In particular, the pressure roller 22 is profitably suited to be operated in rotation so that the peripheral speed of the same pressure roller 22is equal to the linear feeding speed of the products 2, in order to prevent slipping during the contact between the pressure roller 22 and each product 2. For instance, the pressure roller 22 can be activated by the same control means suitable to produce the feeding of the rollers 6 of the conveying line 3 through the interposition of suitable drive means 23 of flexible type. The pressure roller 22 is suitably fastened to the fixed frame of the apparatus 1 through the interposition of an adjustment unit 24 suited to adjust the passage clearance between the roller 22 and the conveying line 3, thus calibrating the entity of the compression to exert on the products 2. The adjustment unit 24 includes worm-screw coupling means

that can be manually operated through a proper control hand-wheel 25.

[0031] The functioning of the apparatus for applying labels on fruits and vegetable products is described as follows.

[0032] The products 2 fed on the conveying line 3 arrange themselves inside the relative concave seats 8 shaped by the rollers 6, aligned along side-by-side lines. The products 2 are therefore conveyed in predetermined positions, which are fixed as to the conveying line 3. The products 2 fed towards the entry station 4 can have a considerable film of moisture on their surface because of the sudden change of temperature they undergo during the transfer from the store rooms to the conveying line 3.

[0033] At this station 4 each product 2 is detected by the sensors 13, which therefore send corresponding activation signals to the control members of the cleaning members 10. The electronically controlled valves interposed in the feeding circuit of the cleaning members 10 perform the emission of a jet of air from the blower nozzles 11. Respective upper portions of the products 2 are therefore hit and cleaned from possible dirt residuals. This preliminary cleaning phase can anyway be excluded in case the products 2 are clean enough.

[0034] Then the products 2 arrive at the heating units 14. Each product 2 in feeding along the conveying line 3, underneath the heating element 18, is hit by localized jets of warm air flowing from the holes 16 to a surface portion of reduced amplitude. In this surface portion a localized warming takes place, suitable for causing the drying of the film of moisture possibly present there.

[0035] Immediately after the phase of localized warming, the products 2 get to the labelling device 30, which applies the labels onto the just dried surface portions 2.

[0036] After the labelling phase, the products 2 undergo the pressing action of the pressure roller 22, which acts on the stuck labels through a compression action suitably modulated through the adjustment unit 24. In case, this pressing phase can be excluded by the functioning cycle, if it is thought to be unnecessary according to the features of the products. Finally, the products 2 get to the exit station 5 to be transferred to the following packaging stations.

[0037] The method and the apparatus according to the claimed invention reach the aim to effectively carry out the application of labels on fruits and vegetable products, preventing these labels from the risk of coming off, in particular for products

characterized by a low adhesive capacity on the external surface, such as kiwis and such. Such aim is achieved thanks to the possibility of operating, through the heating units 14, a selective drying of the product 2, which concerns only the surface portion of the product 2 on which the labels are stuck in an immediately following phase. It should be noted that the cited localized warming safely concerns the surface portion of the product 2 destined to be covered by the label, since the products 2 are arranged in a position predetermined and fixed as to the conveying line 3.

[0038] An important prerogative of the apparatus that carries out the method according to the claimed invention is to be able to adjust in an optimal way the localized warming operated by the heating units 14 depending on the type of products and on the local conditions that affect the moisture external to the product. In fact, it is possible to modulate the localized warming modality by acting both upon the supplied air flow and upon the temperature of the outgoing jets, through the heating elements 18, and also upon the distance between the products 2 and the heating units 14 themselves, to affect the amplitude of the surface portion hit by the jets of warming air.

[0039] An important advantage of the claimed apparatus is to act on the product 2 without altering any of its organoleptic features. In fact, the warming operated by the heating units 14 is localized on a surface portion of the product of limited amplitude, specifically destined to receive the label, and also it has a low intensity. In fact the localized warming takes place at short distance from the labelling device 30, so the warming effect does not fade away even if its intensity is low.

[0040] The possibility to realize a localized warming of low intensity and to concentrate it only on the surface portion relevant to the adhesion of the label, also ensures a profitable management of the fluid and heating energy consumptions. To this consumption economy also contributes the possibility to adjust the position of the sensors 13 which activate the cleaning members 10 such as to limit the time required for the cleaning phase just to what is required by the size of the products 2.

[0041] A further prerogative of the apparatus is to have very limited dimensions, from the structural point of view. This allows not to alter the size of the traditional packaging apparatuses. The claimed apparatus can also be inserted in the

packaging line without severely affecting the noise levels, thanks to the low consumptions of air needed by the heating units 14 to perform the localized warming of the products 2.

[0042] The claimed method and apparatus have very versatile use, depending on the different types of fruits and vegetable products. In particular, according to the various requirements, it is possible to further favour the adhesion of the labels to the products 2 by operating the cleaning through the cleaning members 10 and to further fix the stuck labels through the pressure roller 22.

[0043] Materials adopted for the actual realization of the invention, as well as their shapes and sizes, can be various, depending on the requirements.

[0044] Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the scope of each element identified by way of example by such reference signs.