A METHOD AND AN APPARATUS FOR AFFIXATION OF LABELS

Abstract: There is described a method and an apparatus for affixation of labels onto articles, e.g. parts of packing like plastic lids, which are conveyed to an affixing position to which simultaneously there is conveyed a web of labels, the labels being affixed on the packing part, for example in the form of a plastic lid, where a web of one or more rows of prefabricated labels without supporting web is used, the labels consisting of plastic film, paper or laminate that preferably on the back side is provided with a permanently adhesive glue or a heat activating wax or glue, and where the affixation of the labels in the said affixing position occurs by means of one or more combined punching and affixing pistons which by interaction with cutting plates and retainer plates are used for punching free labels from the label web and to affix the labels on said parts of packing, and which comprises heating means for activating the possibly heat activating glue.

Description: A METHOD AND AN APPARATUS FOR AFFIXATION OF LABELS The present invention concerns a method for affixation of labels on articles, e.g. parts of packing, and of the kind indicated in the preamble of claim 1. In connection with affixation of labels on parts of packing, especially plastic lids, it is commonly known to feed the plastic lids individually to a label dispenser as the feeding occurs by means of special carriers or chain cassettes wherein the single lids are placed. The carriers are disposed on conveyor chains which normally comprise several carriers for transporting the lids from putting stacks, past the label dispenser and further on to re-stacker. The mounting or affixation itself occurs by the carriers conveying a single lid, or possibly several mutually parallel lids in a transverse row, forward to the label dispenser itself where the dispensing occurs by the label, which is mounted on carrying web, being dispensed over a sharp edge or plate. The carrying web on which the labels are mounted, is, in other words, conveyed around a relatively sharp plate edge with very little radius of curvature, so that the label being loosely glued onto the web continues straight forward over the dispenser edge and is moved down onto the packing part, e.g. the plastic lid. Also, it is known to use a conveyor belt, e.g. a vacuum belt, after the dispenser for conveying the label forward to the ac- tual packing part to be labelled, and there to move the label onto the packing part with an air stream. The vacuum used in the conveyor belt is thus substituted by an air stream pressing the label firm onto the packing part. This may be plane or may be shaped as a plastic lid with countersunk mirror surface on which the label is to be affixed. After affixation of the label, the packing part is most often moved onward for restacking as prior to this preferably there is performed an action on the label surface with a lip or a brush pressing the label in place and removing possible air pockets under the label. This prior art method has the disadvantage that it involves two stacking operations, and that the label dispensing furthermore occurs on the individual packing parts while these are conveyed in cassettes. Prior to the label dispensing the packing part is mounted individually in cassettes wherefrom the packing part is then removed again. This requires relatively many complicated mechanical measures in the shape of stacks, re-stacker and cassettes, which in practice imply an unsatisfactory stability when the speed is to be high. In other words, the method is thereby unsuitably resource and time demanding and also relatively cost heavy. Besides, the price of labels on carrying web is relatively high. On this background, the purpose of the invention is to indicate a new and improved method which does not have the drawbacks of the prior art method, and which also enables achieving a more rational handling of the packing parts with a minimum of method steps. The method according to the invention is characterised in that a web of one or more rows of prefabricated labels without supporting web is used, the labels consisting of plastic film, paper or laminate that preferably on the back side is provided with an adhesive coating consisting of a permanently adhesive glue or of a heat activating wax or glue, and that the affixation of the labels in the said affixing position occurs by means of one or more combined punching and affixing pistons which by interaction with cutting plates and retainer plates are used for punching free labels from the label web and to affix the labels on said parts of packing, and which possibly comprises heating means for activating the possibly heat activating glue. By means of simple technical measures it thereby becomes possible to achieve an improved capacity and precision by affixation of labels on parts of packing like plastic lids of the kind comprising a countersunk mirror surface which is arranged for affixation of e.g. prefabricated labels. Suitably the method according to the invention may be thus modified so that the conveying of said packing parts, preferably in the shape of said plastic lids, occurs by means of a plastic film web, wherein one, or preferably a plurality of parallel rows, of plastic lids are formed, preferably by a mermoforming process, that a prefabricated web of labels with a number of parallel rows of labels is used which corresponds to the number of rows of plastic lids in the plastic film web, and that the affixation of the labels occurs by means of a corresponding number of combined punching and affixing pistons. The method according to the invention may suitably be further modified so that the conveying of said parts of packing, preferably in the form of said plastic lids, occurs by means of an endless chain conveyor with transverse carriers in which the parts of packing may be fixed in such a way that the parts of packing successively may be conveyed to said affixing position. The method according to the invention may advantageously be further modified in such a way that there is used a label web coated with permanently adhesive glue, and that the associated conveying means, combined punching and affixing pistons together with the top side of the cutting plate or cutting plates are designed in such a way that the permanently adhesive glue has minimum contact surface on the conveying means, the cutting plate or cutting plates, respectively. Additionally, the invention concerns an apparatus for affixation of labels on articles, e.g. parts of packing like plastic lids, and comprising means for conveying the articles to an affixing position, means for simultaneously conveying a web of labels to be af- fixed the packing part, for example in the shape of a plastic lid. which apparatus is characterised in that for affixing the labels in the said affixing position, it comprises one or more combined punching and affixing pistons which by interaction with cutting plates and retainer plates each are used for punching the labels free from the label web and to affix the labels onto said parts of packing. The apparatus according to the invention may suitably be thus designed that in connection with said combined punching and affixing pistons for use for affixation of labels provided with heat activating glue, it furthermore comprises means arranged for heating at least the lower active part of said pistons. Furthermore, it may be advantageous that the apparatus according to the invention is thus designed that in connection with said combined punching and affixation pistons together with retainer plates for use in affixing labels provided with heat activating glue, it furthermore comprises means arranged for heating at least the upper active part of the retainer plates. The invention is explained more closely in the following with reference to the drawing on which: Fig. 1 shows a side view of a facility for making parts of packing (plastic lids) and labels and for affixing the labels on the lids, Fig. 2 shows a schematic drawing for illustrating of an embodiment of a method and an embodiment of an apparatus according to the invention, respectively, for punching and affixing labels on the mirror surface of individually conveyed plastic lids, Fig. 3 shows a schematic drawing for illustrating a second embodiment of a method and an embodiment of a second apparatus according to the invention, respectively, for simultaneous punching and affixing a number of labels on the mirror surfaces of plastic lids still being continuous in a web and which subsequently are punched and stacked, Fig. 4 shows plastic lid with countersunk mirror surface of the current type, Fig. 5 shows a plastic lid with affixed label on the mirror surface. Fig. 6 shows a web of still continuous plastic lids, and Fig. 7 shows a web of still continuous plastic lids with labels affixed on the mirror surfaces of these. The facility shown in Fig. 1 comprises a section A consisting of an apparatus for thermo forming of plastic lids from a plastic film web 2 from a supply roll 4 consisting of polypropylene (PP), polystyrene (PS), polyethylene (PET) or polyvinyl chloride (PVC). The plastic film web 2 is shaped to lids in a heated state - either by vacuum or pressure forming. Then the plastic film web 2 with the formed lids is conveyed via an accumulating unit 6 with an elevating accumulating roller 8 to a labelling section B that preferably consist of a label printer combined with a label affixation apparatus 10. Alternatively, the labels may be supplied from a roller supply of preprinted label web which is either furnished with permanently active glue (like tape) or with heat activating glue or wax. Also, preprinted label web without adhesive may be used, the adhesive, in the shape of glue or wax, then being supplied in an affixation apparatus 9. After affixation of labels, the plastic film web 2 with the plastic lids are then moved on to a separating section C where punching of the lids occurs. Thereafter a manual or automatic handling of the lids take place, e.g. stacking, packing, etc. In order to ensure optimum adhering of labels on certain plastic film types, it may be necessary, depending on glue or wax type etc., to subject the surface of the plastic film web 2 to a so- called triting at 11 so that the surface tension in the plastic film is adjusted. Such a triting may be performed either as gas or electric triting. A first embodiment of the method and a first embodiment of an apparatus according to the invention, respectively, are illustrated in Fig. 2 showing a preprinted label web 12 of plastic film, paper or laminate with a single row of labels which are advanced between two drawing rollers 14 and positioned via sampling action on photo marks or directly by means of a photo cell on the print to a combination tool in the form of a punching and affixing piston 16 with associated cutting plate 18 and retainer plate 20. From the opposite side, prefabricated plastic lids 22 are fastened individually to cross- bars 24 of an endless chain conveyor 26 and positioned at the underside of the cutting plate 18 so that the retainer plate 20 is correctly placed directly under the plastic lid 22 while the combined punching and affixing piston 16 punches free a label and brings it with downward and fastens the label on the mirror surface 23 of the plastic lid as at least the lower active part of the combined punching and affixing piston 16 is heated if the label is provided with heat activating glue or wax. A preferred, second embodiment of the method and a second, preferred embodiment of an apparatus according to the invention, respectively, are illustrated in Fig. 3 which shows a preprinted label web 28 of plastic film or paper with four parallel rows of labels advanced between two drawing rollers 30 and positioned via sampling action on photo marks or directly by means of a photo cell on the print to a combination tool in the form of four identical punching and affixing pistons 32 with associated cutting plates 34 and retainer plates 36. From the opposite side is conveyed a plastic film web 2 of prefabricated plastic lids 38 which by means of upper and lower advancing wheels 31, which engages between the plastic lids 38, and suitable photo sensors 33. The photo sensors 33 sample, for example, the front side edges of the plastic lids 38 for positioning these at the underside of the cutting plates 34 opposite to the apertures therein so that the retainer plates 36 are correctly placed directly under the plastic lids 38 simultaneously with the combined punching and affixing pistons 32 being moved downward and each punches free a label and brings it with downward through the cutting plate and fastens the label on the mirror surfaces 23 of the plastic lids 38 as at least the lower active parts of the combined punching and affixing pistons 32 are heated if the labels are provided with heat activating glue or wax. For label web 28 and plastic film web 2 apply that high-dynamic motors are used for conveying and positioning as the said photo sensors are connected to one or more positioning controllers for the high-dynamically driven advancing rollers. When the film web 2 with the plastic lids 38 and the label web 28 are correctly positioned, the combined punching and affixing piston 32 are actuated and moved downward through the associated cutting plates 34 so that the labels are punched transversely of the label web 28. Simultaneously, the retainer plates 36 are moved upwards and support the underside of the plastic lids 38 so that a sufficient pressure force for affixing the labels on the plastic lids 38 is ensured. After affixation of a transversely label row, the combined punching and affixing pis- tons 32 are again moved upward, and the retainer plates 36 are lowered simultaneously. Then the label web 28 and the plastic film web 2 with the plastic lids 38, respectively, may again be conveyed one step forward for renewed positioning so that row after row of the plastic lids 38 may have labels affixed. For fastening the labels there may be used different adhesives and binding methods, respectively, depending on choice of paper, plastic film etc. In the case where heat activating glue or wax is utilised, heated punching pistons and/or retainer plates, that suitably may be provided with thermostatically controlled electric heating elements, have to be used. Alternatively, as adhesive there may be used a permanently adhesive glue which by a prior process - e.g. in the same operation at a station immediately before the punching - has been applied the underside of the label web 28. In the case of applying such a permanently adhesive glue, by conveying the label web there is used a special technique sot that the permanently adhesive label web 28 is ensured a stable and even conveying movement, i.e. there is used a conveying technique where the adhesive side of the label web 28 is touched as little as possible. Likewise, the upper side of the cutting plates 34 is designed so that the adhesive side of the label web 28 easily lets go of the cutting plates 34 after the punching. A combination of angle between the upper side of the cutting plates 34 and the label 28 compared with correct tension in the label web thus enables separation of the adhesive underside of the label web from the upper side of the cutting plates 34. The plastic lid 38 shown in Fig. 4 is designed in a known way with a central, countersunk mirror surface 23 intended for receiving a prefabricated label 25, cf. e.g. Fig. 5. Fig. 6 shows a plastic film web 2 which, for example, by thermoforming is designed with mutual parallel rows of identical plastic lids 38 which are not yet punched for forming individual plastic lids 38. Correspondingly, Fig. 7 shows a plastic film web 2 with continuously coherent plastic lids 38 that each have labels 25 affixed on the countersunk mirror surfaces 23.

Claims: CLAIMS 1. A method for affixation of labels onto articles, e.g. parts of packing like plastic lids, which are conveyed to an affixing position to which simultaneously there is conveyed a web of labels, the labels being affixed on the packing part for example in the form of a plastic lid or a corresponding, preferably plane, part of a packing, c h a r a c t e r i s e d in that a web of one or more rows of prefabricated labels without supporting web is used, the labels consisting of plastic film, paper or laminate that preferably on the back side is provided with an adhesive coating consisting of a per- manently adhesive glue or of a heat activating wax or glue, and that the affixation of the labels in the said affixing position occurs by means of one or more combined punching and affixing pistons which by interaction with cutting plates and retainer plates are used for punching free labels from the label web and to iffix the labels on said parts of packing, and which possibly comprises heating means for possibly acti- vating the heat activating glue. 2. A method according to claim ^ c h a r a c t e r i s e d in that the conveying of said parts of packing, preferably in the form of said plastic lids, takes place by means of a plastic film web in which one row, or preferably a plurality of parallel rows, of plastic lids are formed, preferably by a thermoforming process, that a prefabricated web of labels with a number of parallel rows of labels is used which corresponds to the number of rows of plastic lids in the plastic film web, and that the affixation of the labels occurs by means of a corresponding number of combined punching and affixing pis- tons. 3. A method according to claim 1, c h a r a c t e r i s e d in that the conveying of said parts of packing, preferably in the form of said plastic lids, occurs by means of an endless chain conveyor with transverse carriers in which the parts of packing may be fixed in such a way that the parts of packing successively may be conveyed to said affixing position. 4. A method according to claim 1, characterised in that there is used a label web coated with permanently adhesiveglue, and that the associated conveying means, combined punching and affixing pistons together with the top side of the cutting plate or cutting plates are designed in such a way that the permanently adhesive glue has minimum contact surfaceon the conveying means, the cutting plate or cutting plates, respectively. 5.'An apparatus for affixation of labels on articles, e.g. parts of packing like plastic lids, and comprising means for conveying the articles to an affixing position, means for simultaneously conveying a web of labels to be affixed the packing part, for example in the shape of a plastic lid, characterised in that for affixing the labels in the said affixing position, it comprises one or more combined punching and affixing pistons which by interaction with cutting plates and retainer plates each are used for punching the labels free from the label web and to affix the labels onto said parts of packing. 7 6. An apparatus according to claim characterised in that in connection with said combined punching and affixing pistons for use for affixation of labels provided with heat activating glue, it furthermore comprises means arranged for heating at least the lower active part of said pistons. 7. An apparatus according to claim ), characterised in that in connection with said combined punching and affixation pistons together with retainer plates for use in affixing labels provided with heat activating glue, it furthermore comprises means arranged for heating at least the upper active part of the retainer plates.

Inventors: RASMUSSEN LEIF, RASMUSSEN, LEIF
Applicants: RASMUSSEN LEIF, RASMUSSEN, LEIF
Application year: 2000
Main classification: B65C1
IPC codes: B65C1, B65C9