EP0344674A1

EP0344674A1 - Device for closing tubular wrappers at at least one end thereof

Info

Publication number: EP0344674A1
Application number: EP89109627A
Authority: EP
Inventors: Marcelo Quadrana
Original assignee: SASIB SpA
Current assignee: SASIB SpA
Priority date: 1988-06-03
Filing date: 1989-05-29
Publication date: 1989-12-06
Also published as: IT8912467A0; IT1232477B; AR245033A1

Abstract

When making wrappers for cigarette packs, a folder (4) consisting of a thin blade of a thickness smaller than 1 mm, is used for having the first flap (A) of a tubular wrapper (3) folded from one of the two long sides of the one end of a cigarette pack on one of the rectagular end sides thereof, and the said thin blade will be kept over the flap (A) having been folded on the one rectangular end side of the cigarette pack, until the two side folds (B) formed from the two short sides of the one end portion of wrapper (3) will have been folded on the same rectangular end side of this cigarette pack. Thus, the two side folds of wrapper (3) will be folded on the thin blade of folder (4), and this folder (4) is then slipped out from in between the flap (A) lying thereunder and the two side folds (B) placed thereupon.

Description

The object of the invention is a method for closing tubular wrappers at at least one end thereof being rectangular in shape, with two long sides and two short sides, particularly tubular wrappers for cigarette packs, according to the introductory portion of Claim 1. For carrying out this method, the invention provides a device according to the introductory portion of Claim 2.
By the known methods and in the known devices of the above mentioned type, in order to have the first flap formed from one end portion of a wrapper by causing one of the two long sides thereof to be folded on one of the wrapper end sides, a relatively thick folder was used, which after the said first wrapper flap having been folded thereby, was retracted from the one wrapper end side, before the two side folds formed from the two opposite short sides of the same one end portion of the wrapper having been folded on the same one wrapper end side. On the said folder being retracted, this folder may drive along the just folded first flap, so that this flap may be lifted, or it may be so deformed as to impair the successive regular folding of the two side folds and of the second flap formed from the other long side of the same one end portion of the wrapper on the same one wrapper end side, so that this one end side of the wrapper may be imperfectly closed.
The object of the invention is to eliminate the said drawback, and to provide a method according to the introductory portion of Claim 1, whereby the proper positioning is ensured of the first flap formed from one end portion of a wrapper by causing one of its two long sides to be folded on one of the wrapper end sides, while any displacement and deforming of said flap will be prevented from occurring up to the folding thereon of the two side folds formed from the two short sides of the same one end portion of this wrapper.
This problem is solved by the features according to the characterizing portion of Claim 1.
By the method according to the invention, the thin blade folder which causes the first flap formed from one of the two long sides of one end portion of a wrapper to be folded on one of the end sides of this wrapper, is kept, after having performed its folding action, at the one end side of the wrapper, in a position in which this folder at least partly covers the said folded first flap, until the two side folds formed from the two opposite short sides of the same one end portion of this wrapper will have been folded on the same one end side of this wrapper. Therefore, the first folded flap will not be driven along, will not be displaced or deformed by the said folder, owing to this folder being moved into its retracted position, but this flap will be held by the very same thin-blade folder in the proper position on the plane of the one end side of this wrapper, and the two side folds formed on the same wrapper end side from the two short sides of the same one wrapper end portion, on being folded will overlap the folder, which is nextly retracted and slipped out from in between the folded flap lying under the said folder, and the two side folds placed thereupon. However, such a retraction movement of the thin-blade folder does not bring about any displacement and/or any deformation of the already folded first flap, since this flap is held in position by the two folded side flaps, which overlap the respective side end of the first flap.
To carry out the method of the invention, a device is used according to the introductory portion of Claim 2, which is characterized by the features as specified in the characterizing portion of said Claim.
Further beneficial features of the device according to the invention are stated in the other dependent Claims.
The method and the device according to the invention will clearly appear from the following specification of one preferred embodiment thereof, which is diagrammatically shown by way of a non-limiting example in the accompanying drawings, in which:

Figure 1 is a front view showing the folding station of a device according to the invention.
Figure 2 is a side wiew of the folding station of the device according to Figure 1.
Figure 3 is an exploded, perspective view showing the single components of a-thin blade folder, according to the invention.
Figures 4 to 8 are perspective views showing the sequential steps of closing one end side of a tubular wrapper by the method of the invention, and by means of the relative device shown in Figures 1 to 3.

The shown device forms an integrating part of a packaging machine, particularly a machine for packaging cigarettes, or the like. This device comprises, in known manner, ring-like arranged successive box-shaped tubular forms 1 which are intermittently moved over a circular path 2, in the direction, for example, of arrows F1 in Figure 1, so that each box-shaped tubular form is caused to pass through a plurality of successive stations, and to dwell for a certain time in each one of them.
Each box-shaped tubular form 1 has a rectangular profile in cross-section, and its long sides are directed substantially radially to the circular path 2, while its short sides are directed tangentially to the said path 2.
The means for supporting and operating the ring-like arranged, box-shaped tubular forms 1 are known. Also known are the operations to be performed in the successive stations by means of each box-shaped tubular form 1. In Figure 1 only three successive stations I, II, and III are shown for the box-shaped tubular forms 1. In station I and in one or more of the preceding stations, a tubular wrapper 3 is formed around each box-shaped tubular form 1, and is meant for becoming an integrating part of a cigarette pack, or a covering therefor. An end portion of this tubular wrapper 3 is caused to protrude from one end of a box-shaped tubular form 1, as it appears particularly in Figure 4. The protruding end portion of this tubular wrapper 3 is to be closed in the folding station II by having the four sides of this protruding end portion of the tubular wrapper 3 folded upon the relative end side of a box-shaped tubular form 1.
For this purpose, a first folder 4 is provided in station II, and is associated with one of the two long sides of the one end of a box-shaped tubular form 1 coming to be located in this station, particularly with the long upper side of the head end thereof, as in the shown embodiment. This folder 4 consists of a thin blade of a thickness smaller than 1 mm, and preferably a thickness between 0.5 and 0.3 mm, and by its upper side edge which is parallel to the associated long one end side (long head end side in the Figures) of this box-shaped tubular form 1, this blade is secured by means of screws 5 to the respective side edge of a supporting platelet 6 which is perpendicular to blade 4 and is arranged on the side of said blade which is turned away from the box-shaped tubular form 1. The supporting platelet 6 is much thicker than the blade 4, and so it is quite rigid. The said platelet 6 is secured by means of screws 7 and an L-shaped element 8, to a driving shaft 9 which is rotatably supported in the folding station II, and is parallel to the one end side (head end side, as shown) of a box-shaped tubular form 1 coming to be located in this station. Thus, the thin-blade folder 4 can be moved by this shaft 9 angularly around the shaft 9 itself, and transversally to the associated long one end side (long upper head end side in the Figures) of a box-shaped tubular form 1, from a retracted position shown in Figures 7 and 8, and by dash-and-dot lines in Figure 2, into an active position shown in Figures 2, 5, and 6, in which the thin-blade folder 4 comes to be parallel to the one end side (head end side here) of a box-shaped tubular form, and close thereto.
The supporting platelet 6 extends preferably throughout the width of the thin-blade folder 4. From the side edge of the supporting platelet 6 which contacts the thin-blade folder 4, a median rib 106 extends over almost the entire height of blade 4, and bears also against the said blade 4. Thus, the thin blade 4 is stiffened to a sufficient degree for carrying out its folding function, while the two lateral areas of its flat face lying opposite to a box-shaped tubular form 1, are left clear for the purpose to be disclosed later on.
Further provided in the folding station II are two side folders 10 and 11 which are associated with the two opposite short sides of the one end of a box-shaped tubular form 1 coming to be located in this station, particularly with the two short sides of the head end thereof, as in the shown embodiment. These two side folders 10, 11 are fixedly fitted on swingable folder-carrying arms 12, 13 which are rotatably supported by, and are swingable about pivots 14, 15 being parallel to each other and perpendicular to the plane of the one end side (head end side, as shown) of a box-shaped tubular form 1. The two folder-carrying arms 12, 13 are connected together by means of sector gears 112,113, co-axial to pivots 14, 15. An eccentric extension 212 of the folder-carrying arm 12 is pivotally connected through a link 16 to the crank arm 17 of a driving shaft 18 which in the folding station II is rotatably supported by frame 19. The two side folders 10, 11 can be synchronously moved angularly by this shaft 18, so as to be caused to swing about their respective pivot 14, 15, and transversally to the associated short one end sides (short head end sides, as shown) of a box-shaped tubular form 1, from a sideward, outwadly retracted position (open position), shown in Figures 1, 4, 5, 7, and 8, into an active position (closed position), shown in Figure 6, in which the two folders 10, 11 come to be located in front of the one end side (head end side, as shown) of a box-shaped tubular form 1, in a parallel, close relation therewith.
A stationary folder 20 is associated with the other long side of the one end of a box-shaped tubular form 1 coming to be located in the folding station II, particularly with the long lower head end side thereof as in the shown embodiment, and is fixed to frame 19 in such a position that the one end side (head end side in the Figures) of the box-shaped tubular form 1 will graze the said stationary folder 20, as this box-shaped tubular form 1 is being moved over its path 2 in the direction of arrow F1, from the folding station II into the successive station III.
Through the associated driving shafts 9 and 18, the movement of the thin-blade folder 4 and of the two side folders 10, 11 is so controlled that the operation of said folders will be as follows.
Whenever a box-shaped tubular form 1 is reaching the folding station II, the folders 4, 10 and 11 are located in their retracted position, as shown in Figure 4. Nextly, while this box-shaped tubular form 1 is being caused to dwell in station II, the thin-blade folder 4 is first actuated and moved from its retracted position shown in Figure 4, into its active position shown in Figure 5. Thus, the thin-blade folder 4 will fold upon the one end side of this box-shaped tubular form 1 a flap A formed from that end portion of a tubular wrapper 3 which protrudes from the one end of the box-shaped tubular form, and lies in an adjoining relation with that long side of the one end thereof which is associated with the said thin-blade folder 4 (long upper head end side in the Figures). After the said flap A having been thus folded, the thin-blade folder 4 is kept in its active position at the one end side (head end side, as shown) of this box-shaped tubular form 1, over the just folded flap A, and the two opposite side folders 10, 11 are moved into their active position, i.e., closed position, as shown in Figure 6. These two side folders 10, 11 will fold upon the one end side (head end side in the Figures) of this box-shaped tubular form 1 the two side folds B formed from that end portion of wrapper 3, which protrudes from the one end (head end, as shown) of the box-shaped tubular form 1, and lies in an adjoining relation with the two opposite short sides of said one end. However, since the thin-blade folder 4 is still kept at the one end side (head end side, as shown) of this box-shaped tubular form 1, the said two side folds B of wrapper 3 are folded upon the thin-blade folder 4, which at least in part covers the previously folded flap A, and accurately holds the same in position.
Thereafter, the thin-blade folder 4 is returned into its retracted position, so that it is slipped out from in between the folded flap A and the two folded side folds B. Also the two side folders 10, 11 are opened, i.e., returned into their retracted position, either simultaneously, or a little in advance or with a little time lag, so that the one end side (head end side in the Figures) of this box-shaped tubular form 1 is left clear, as shown in Figure 7. This box-shaped tubular form 1 is then moved from the station II into the successive station III, and while the said form 1 is being thus moved, the stationary folder 20 will fold upon the one end side (head end side, as shown) of the box-shaped tubular form 1 the flap C formed from the remaining end portion of the tubular wrapper 3, which protrudes from the one end (head end, as shown) of the box-shaped tubular form 1, and lies in an adjoining relation with that long one end side thereof which is associated with the stationary folder 20 (lower long head end side), as shown in Figure 8.
The closed end side of a tubular wrapper 3 is as shown in Figure 1, at station III.

Claims

1. A method of closing tubular wrappers (3) at at least one end thereof being rectangular in shape, with two long sides and two short sides, particularly tubular wrappers for making cigarette packs, or the like, by the sequential steps of having one first flap (A) formed from one end portion of a wrapper (3), by causing one of the two long sides thereof to be folded on one end side of wrapper (3), and then of having two side folds (B) formed from the same one end portion of wrapper (3), by causing the two opposite short sides thereof to be folded on the same one end side of wrapper (3), and finally of having a flap (C) formed from the same one end portion of wrapper (3), by causing the other long end side thereof to be folded on the same one end side of wrapper (3), respectively by the folders (4, 10 - 11, 20) which are temporaneously brought close to the one end side of wrapper (3) by a relative movement which grazes the plane of the one end side of wrapper (3), transversally to the sides of the one end side thereof, characterized in that for causing the first flap (A) to be folded from one of the two long sides of the one end of wrapper (3), a folder (4) is used, which is so thin that the two side folds (B) formed from the two opposite short sides of the same one end portion of wrapper (3), can be folded upon this folder (4), and after the first flap (A) having been folded by the said thin folder (4), the thin folder (4) is kept stationary at the one end of wrapper (3) over the folded flap (A), until the two side folds (B) will have been folded, so that these side folds (B) will overlap the folder (4), whereupon the said folder (4) is retracted from the one end of wrapper (3) and is slipped out from in between the flap (A) lying thereunder and the two side folds (B) placed thereupon.

2. A device for carrying out the method according to Claim 1, which comprises ring-like arranged box-shaped tubular forms (1) being rectangular in cross-section, with two long sides and two short sides, the said ring-like arranged box-shaped tubular forms (1) being stepwise rotated so as to have each box-shaped tubular form (1) moved into a plurality of successive processing stations (I, II, III), and each box-shaped tubular form (1) comes to one (II) of these stations with a tubular wrapper (3) having been formed therearound, the said wrapper (3) protruding by an end portion thereof from one end of a box-shaped tubular form (1), and provided in station (II) are a folder (4) which is associated with the one end side of a box-shaped tubular form (1), and is movable transversally to one of the two long sides of this one end of the box-shaped tubular form (1), and is intended for folding one first flap (A) formed from one of the two long sides of the protruding end portion of wrapper (3) on the one end side of a box-shaped tubular form (1); two side folders (10, 11) which are movable transversally to the two opposite short sides of the one end of this box-shaped tubular form (1), and are intended for folding on the same one end side thereof two side folds (B) formed from the two short sides of the protruding end portion of wrapper (3); and a folder (20) which is associated with the other long side of the one end of this box-shaped tubular form (1) and is intended for folding on the same one end side thereof a second flap (C) formed from the other long side of the protruding end portion of wrapper (3); characterized in that the movable folder (4) which is intended for folding one first flap (A) of wrapper (3) from one of the two long sides of the one end of a box-shaped tubular form (1) on the one end side thereof, consists of a blade having a thickness smaller than 1 mm, preferably a thickness of 0,5 - 0.3 mm, the said folder (4) being so controlled that after the flap (A) of wrapper (3) having been folded thereby on the one end side of a box-shaped tubular form (1), this folder (4) will be kept over the said flap (A) until the two side folds (B) of wrapper (3) will have been folded from the two short end sides of the one end of the box-shaped tubular form (1) on the same one end side thereof, respectively by the two side folders (10, 11).

3. The device according to Claim 2, characterized in that the blade of folder (4) for folding the first flap (A) from one of the two long sides of the one end of a box-shaped tubular form (1) on the one end side thereof, is secured to a movable rigid support (6) having one or more blade-stiffening extensions (106) which bear against the said blade face which is opposite to the one end of a box-shaped tubular form (1), the said extensions (106) however leaving two lateral areas of said face clear for the two side folds (B) to be folded on the same one end side of wrapper (3).

4. The device according to any one of Claims 2 or 3, characterized in that the blade of folder (4) for folding the first flap (A) of wrapper (3) from one of the two long sides of the one end of a box-shaped tubular form (1) on the one end side thereof, is through its support (6) swingably fitted on a shaft (9) which is parallel to the two long sides of the one end of a box-shaped tubular form (1), the said blade being caused to assume an active position for folding the flap (A), which is parallel and close to the said one end side.

5. The device according to any one of Claims 2 to 4, characterized in that the two side folders (10, 11) which are intended for folding the two side folds (B) of wrapper (3) from the two opposite short sides of the same one end of a box-shaped tubular form (1) on the same one end side thereof, are swingably fitted on pivots (14, 15) being parallel to each other and perpendicular to the plane of the said one end side, the said two folders (10, 11) being connected together by means of sector gears (122, 113), co-axial to said pivots (14, 15), about which the said folders (10, 11) are caused to swing.