GB2253578A

GB2253578A - Print device in cigarette machine

Info

Publication number: GB2253578A
Application number: GB9205352A
Authority: GB
Inventors: Fiorenzo Draghetti
Original assignee: GD SpA
Current assignee: GD SpA
Priority date: 1991-03-14
Filing date: 1992-03-12
Publication date: 1992-09-16
Anticipated expiration: 2012-03-12
Also published as: ITBO910078A0; ITBO910078A1; DE4207788A1; IT1245883B; GB2253578B; GB9205352D0

Abstract

The device comprises a set of gumming rollers (1) serving to apply an adhesive trace to a running strip of cigarette paper (2), applicator rollers (3) by which a powdered metal is deposited on the face (21) of the strip bearing the adhesive trace, and a suction device (6) which distances the surplus metal detached from the strip (2) following application; a more thorough removal of the surplus metal is brought about by a device (7) operating in concert with the suction device (6), which causes the strip (2) to vibrate as it runs through. <IMAGE>

Description

2253578 1 A print device in a cigarette manufacturing machine The present

invention relates to a print device, in a cigarette manufacturing machine. More particularly, the invention relates to those devices capable of reproducing Scripts or motifs on cigarettes, not by applying traditional inks, but utilizing powdered metals similar in colour to gold or silver with the end in view of enhancing the appearance of the cigarettes. Such devices will generally make use of a gumming mechanism by which one face of a continuous strip of paper, constituting the external casing of the cigarettes, is invested with an adhesive trace of the script or motif it is wished to reproduce in a metallic colour. Thereafter, a layer of pulverulent material, generally a powdered metal such as bronze in simulation of gold, is applied at least to the gummed areas and thus caused to adhere. The aim of such a process is to obtain a script or motif as near perfect in reproduction as possible and with a uniform and homogeneous distribution of 2 the pulverulent metallic material. This is achieved by applying a quantity of powdered metal surplus to requirements, and then seeking to remove the excess from the non-gummed areas. Methods widely adopted for the removal of surplus pulverulent metallic material include the use of brushes, placed in contact with the gummed face of the running continuous strip and set in rotation in a direction contrary to the feed direction, and of small diameter diverting rollers placed in contact with the reverse face of the strip in such a way as to remain partly enveloped. The practical effect of passing the continuous strip over a roller of small diameter is to subject the face not in contact with the rolling surface to tensile stresses which tend to detach any particles of the pulverulent metallic material not adhering to the script or motif traced in gum. To achieve a still more efficient removal of the excess pulverulent material, use is made of suction means which produce an action such as will forcibly remove the material and distance it from the strip. US patent 1,239,995 discloses a device of the type in question, which comprises three brushes disposed in sequence between two feed rollers and positioned 3 in such a way as to remove excess powdered material from the strip by mechanical action. By contrast, US 3,380,436 discloses a print device comprising a pair of diverting rollers of which one operates in conjunction with an electrostatically charged brush or grille. This same roller is also located within the compass of suction means serving as aforementioned to bring about a more efficient removal of the surplus pulverulent material; thus, the excess is removed by mechanical action and/or electrostatic action. Another conventional device is designed to enhance the efficiency of the suction means, given that all of the devices mentioned thus far have been found unable to effect a complete removal of the surplus pulverulent material in question; this comprises a pierced plate positioned within the compass of the suction means, across which the gummed face of the running continuous strip is made to pass. To render the action of the suction means fully effective, that is to say, by exposing the gummed face of the strip to a degree of negative pressure such as will ensure a thorough removal of the excess pulverulent material, the gummed face of the running strip must be made in practice to adhere to the pierced plate.

4 Such an arrangement has given rise in its turn to a fresh and more serious drawback, namely, that the friction resulting from contact gradually retards the progress of the strip, and the correct timing is lost at successive work stations. The object of the present invention is to provide a print device capable of bringing about an efficient removal of surplus pulverulent material without any upset to the timing of the running strip. The stated object is realized in a print device for cigarette manufacturing machines according to the present invention, comprising a gumming device by means of which to apply an adhesive trace to,a running continuous strip of paper, an applicator device by which a powdered metal is deposited on the face of the continuous strip bearing the adhesive trace, and suction means acting on the face of the continuous strip bearing the adhesive trace, characterized in that it further comprises vibrator means designed to set up vibrations in the continuous strip at least when passing within the compass of the suction means. The invention will now be described in detail, by way of example, with the aid of the accompanying drawings, in which:

-fig 1 illustrates a device embodied according to the present invention, viewed in cross section; -fig 2 is a detail of the device of fig 1, shown in an alternative embodiment; -fig 3 is a detail of the device of fig 1, viewed from W and shown in a further embodiment. The print device according to the present invention comprises a gumming device denoted 1, toward which a strip of paper 2 is fed continuously, for example by a pair of pinch rolls 10. The gumming device 1 comprises a gumming roller 11 and at least one feed roller 12; two are shown in the example of fig 1. The gumming roller 11 affords at least one surface in relief 14 corresponding to the adhesive trace to be applied to the strip, and rotates about its own axis permanently in contact with one face 21 of the strip 2 on the one hand, and with one of the two feed rollers 12 on the other. The gumming device 1 is completed by a container 13 holding adhesive in which one of the feed rollers 12 is part-immersed. 3 denotes a powdered metal or bronze applicator occupying a position beyond the gumming device 1, considered in relation to the feed direction of the continuous strip 2, which consists for example in a pair of rollers 31 rotating in mutual contact and 6 positioned one in contact with the gummed face 21 of the continuous strip 2, the other dipping into a container 32 filled with the pulverulent metallic material 15 to be deposited on the face 21 of the strip 2. At a certain point beyond the applicator 3, the strip 2 is directed over a diverting roller 5, in such a way that the roller remains partly enveloped by the reverse, that is, the non-gummed face 22; thereafter, the strip encounters suction means 6. 4 denotes a cylindrical element, stationed between the applicator device 3 and the diverting roller 5, which is rotatable about its own axis and remains permanently in tangential contact with the gummed face 21 of the running strip 2. This cylindrical element 4, which might be a brush, revolves in the direction opposite to that followed by the strip 2 in such a way that the gummed face 21 is subjected to a mechanical action aimed at removing any excess pulverulent material 15. The print device further comprises vibrator means 7 located within the compass of the suction means 6, and positioning means 8 which serve to prevent any interference with the gummed face 21 of the strip 2 at least while exposed to the suction means 6.

1 7 As discernible from figs 1 and 2, the continuous strip 2 passes beyond the diverting roller 5 and over a fixed structure 16, with which it combines to encompass two chambers 161 and 162 disposed in succession and connected with means of generating suction (not illustrated) by way of ducts 61 that constitute a part of the suction means 6. In the embodiment of fig 1, the device comprises a nozzle 9 emerging into the first chamber 161, which is directed at the running strip 2 and connected to a source of pressurized fluid, for example air. In a preferred embodiment, the air will be supplied to the nozzle 9 intermittently, in such a way that the strip 2 is invested repeatedly with jets of air and thus caused to vibrate. The vibrator means 7 might be embodied differently. In the example of fig 2, for instance, such means 7 comprise at least one mechanical component 17 with a cam profile, which when set in rotation engages the running strip 2 pulsatingly and thus generates the desired vibration. At all events, the nozzle 9 and pressurized fluid system affords numerous advantages, including the facility of regulating the force applied to the running strip 2 in order to achieve its vibration.

8 4 In the chamber 162 following that occupied by the nozzle 9, the running strip 2 is further exposed to suction, to the end of ensuring that every excess particle of the pulverulent material 15 is removed from the relative face 21. The positioning means 8, which prevent the gummed face 21 of the strip 2 from coming into contact with any part of the device, might consist simply in a diverting roller 5 as illustrated in fig 1, in combination with a fixed guide element 81 located between the suction chambers 161 and 162, of which the active surface is rounded in such a way as to minimize frictional contact with the strip 2; this same element 81 functions simultaneously as a means of damping vibration out of the strip 2 once beyond the vibrator means 7. Fig 3 illustrates a variation of the embodiment shown in fig 1, in which the nozzle 9 is positioned between two ports 611 associated with the ducts 61. The advantages of the print device according to the invention derive essentially from its extreme simplicity in construction and operation. A further advantage of the invention is the absencd of any component or element that could enter into contact with the strip 2 during its exposure to the 11 9 suction means 6 and the vibrator means 7, and thus hinder its progress.

I 4 1 claims A print device in a cigarette manufacturing machine, comprising a gumming device by means of which to apply an adhesive trace to a running continuous strip of paper, an applicator device by which a powdered metal is deposited on the face of the continuous strip bearing the adhesive trace, and suction means acting on the face of the continuous strip bearing the adhesive trace, characterized in that it further comprises vibrator means designed to set up vibrations in the continuous strip at least when passing within the compa!s of the suction means.

2) A print device as in claim 1, further comprising positioning means of which the essential purpose is to prevent any interference with the gummed face of the running strip at least while exposed to the suction means.

1 11 A print device as in claim 1, wherein the vibrator means consist in at least one nozzle.from which a pressurized gaseous fluid is-directed at the passing strip.

4) 5) 6) A print device as in claim 3, wherein the vibrator means consist in at least one nozzle from which a pressurized gaseous fluid is directed intermittently at the passing strip.

A print device as in claim 1, wherein the vibrator means consist in at least one nozzle positioned and operating within the compass of the suction means, from which a pressurized gaseous fluid is directed continuously or intermittently at the passing strip.

A print device as in claim 1, wherein the vibrator means consist in at least one rotating mechanical component affording a cam profile, positioned to interact with the passing strip.

A print device in a cigarette manufacturing machine substantially as described with reference to the figures of the accompanying sheet of drawings.

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