EP0106274A2

EP0106274A2 - Device for feeding webs or sheets of packaging or wrapping material to packaging or wrapping machines

Info

Publication number: EP0106274A2
Application number: EP83109966A
Authority: EP
Inventors: Roberto Cavazza
Original assignee: SASIB SpA
Current assignee: SASIB SpA
Priority date: 1982-10-08
Filing date: 1983-10-05
Publication date: 1984-04-25
Also published as: IT8212633A0; IT1157759B; EP0106274A3

Abstract

This invention relates to a device for feeding webs or sheets of packaging or wrapping material (hereinafter called "packaging material"), specifically a material of low rigidity, to packaging or wrapping machines, wherein the web (N) or the sheet (F) is fed, usually in a vertical direction, across a runway (1,2) wherealong the articles (P) to be packaged are advanced, through an inlet transverse slot (3) formed in a wall, usually the upper wall (2), of said runway, and then through an outlet transverse slot (103) formed in the opposite wall, usually the lower wall (1), of said runway. Thus, the web (N) or sheet (F) forms a curtain which is engaged, bent into a U shape and dragged by the article (P) to be packaged, which is advanced along said runway by a pusher (5,105). The invention provides a web- or sheet-guide member (11), preferably of tubular shape, which can be moved across the runway (1,2) where the articles (P) to be packaged are advanced, and can be introduced through the outlet transverse slot (103) of said runway up to the inlet transverse slot (3) thereof, so as to receive the free end of the web (N) or sheet (F) existing from the inlet slot (3) and to guide it down to and through the opposite inlet slot (103). The web- or sheet-guide member (11) then withdraws from the runway (1,2), whereby an article (P) to be packaged can be advanced past the curtain formed by the web (N) or sheet (F) which has been fed.

Description

This invention relates to a device for feeding webs or sheets of packaging material to a packaging machine, wherein the web or sheet is fed, usually in a vertical direction, across a runway wherealong the articles to be packaged are advanced, through an inlet transverse slot in a wall, usually the upper wall, of said runway and then through an outlet transverse slot in the opposite wall, usually the lower wall, of said runway, so as to form a curtain which is engaged, bent into a "U" shape and dragged by the article to be packaged which is advanced along said runway by means of a pusher.
When the packaging material used in the packaging machines of this type is of poor rigidity and is too flexible, such as polyethylene, cellulose film of the type known as "Cellophane" (Reg. Trademark) or the like, the web or sheet being fed tends to jib and clog against the guides and hardly follows the pre-established path of travel. To obviate this drawback, the use is known of guides formed by two rows of parallel, opposite and staggered strips, arranged so that the ridges of the strips of a row are inside the ridges of the strips of the other row. Thus, the web or sheet is given, over the width thereof, a sinuous configuration behaving as an assembly of longitudinal stiffening ribs. Moreover, the use is known of gentle jets of compressed air substantially in the direction of advance of the web or sheet, to increase the stability of the trajectory thereof. All these known provisions only partially avoid the risk of a web or sheet jibbing against the guides, because they cannot be used at the region which crosses the runway where= along the articles P are advanced, where the end of the web or sheet emerging from the inlet slot must cross, while not guided, said runway and get inserted into the opposite outlet slot.
Practically, the free, not guided, end of the web or sheet often diverts from its normal trajectory while crossing said runway whereby it will not get inserted into said outlet slot and its leading end will jib against the respective wall of the runway.
This invention aims to obviate said drawback, and for this purpose it provides a web- or sheet-guide member which can be moved across the runway where the articles to be packaged are advanced, and can be introduced through the outlet transverse slot of said runway up to the opposite inlet transverse slot thereof, so as to receive the free end of the web or sheet being passed through the inlet slot and to guide it down to and through the opposite outlet slot, and said guide member then withdraws from the runway, whereby the article to be packaged can be advanced past the curtain of web or sheet which has been fed.
Preferably, the movable guide member for the web or sheet is of tubular formation and is connected to a suction source either to facilitate the insertion of the end of the web or sheet into the mouth of said guide member and to avoid any jibbing or clogging of the web or sheet within the guide member therefor .
These and other features of the invention, and the advantages resulting therefrom will be apparent from the following description of a preferred embodiment thereof, shown by way of non-limitating example in the accompanying drawings, wherein:

Figure 1 is a vertical sectional view of the web--feeding device in a conventional. cellophaning machine for packages of cigarettes;
Figure 2 is a diagrammatic top plan view thereof, as seen from the arrows II-II of Figure 1.

In the Figures, the reference numeral 1 indicates the horizontal table supporting the packages of cigarettes P . intended to be wrapped in a cellophane wrapper. The table 1 forms, together with members 2 spaced thereabove, a horizontal runway wherealong the packages P are advanced.
A series of individual cells 104 of a star-shaped operating wheel 4 will be moved sequentially stepwise to a position co-axially in front of the outlet end of said advancement runway.
A cellophane sheet F can be disposed vertically across the advancement runway in curtain-like fashion through a transverse slot 3, so-called inlet slot, formed in the upper wall of said runway, and an opposite transverse slot 103, so-called outlet slot, formed in the lower rest table I. During the dwell period of each cell 104 of the operating wheel 4, a package of cigarettes P is advanced by means of a pusher 5,105 along said runway on said table 1 thereof, so as to engage a sheet F disposed in curtain-like fashion across the runway, thus drawing off said sheet F from the inlet and outlet slots 3 and 103, bending it into a U shape and dragging it forwards, to be finally accommodated together with said cellophane sheet F into a cell 104 of the operating wheel 4. Figure 1 shows with full lines the position of the pusher 5,105 and package of cigarettes P when the latter has just engaged the cellophane sheet F, and with dot-and-dash lines the position of the package P transferred into the cell 104 together with the sheet F, and respective advanced position of the pusher 5,105. The star-shaped operating wheel 4 is then rotated one further step and the successive empty cell 104 thereof is transferred in front of the outlet end of said runway along which the packages of cigarettes P to be wrapped with cellophane are moved.
The cycle described above is then repeated, while the formation of the cellophane wrapper around the package P is being completed on the star-shaped operating wheel 4.
The pusher 5,105 for transferring the packages P from the runway to the operating wheel 4 is constructed, preferably, according to the Italian Patent IT-A-1.049.141; accordingly, it is formed of two halves 5,105 which are joined with each other and constitute a unitary pusher when a package P is pushed along said runway and is transferred together with a sheet F into a cell 104 of the operating wheel 4, as shown with full lines in Figure 2, and which thereafter separate and move away from each other laterally while being returned to the initial position thereof along a widely arcuated path of travel around the position of a new cellophane sheet F to permit this sheet to be fed and positioned across the runway along which the packages P are being advanced during the return stroke of the pusher 5,105, as shown in Figure 2, where some positions of the two halves 5,105 of the pusher are shown with dot-and-dash lines.
The sheet of cellophane F is severed, by means of a rotating blade cutter 6 with fixed counter-blade 106, from the lower free end of a web of cellophane N fed from above by means of two feed rollers 7,107. The sheet F is severed from the web N as soon as the sheet F is engaged by a package, or shortly after, so that the lower free end of the web N will first be moved downwards across the runway for the packages P, and will be passed through the upper inlet slot 3 and lower outlet slot 103. Upon this downward movement, the end portion of the web of cellophane N is guided between lateral guide walls 8,108 located below the cutter 6,106. To prevent the end of the web N from jibbing against these side walls 8,108 and thus to ensure a correct insertion of the end portion of the web N into the inlet slots 3, the lateral guide walls 8,108 are provided with holes 9,109 communicating with ducts 10,110 emitting jets of compressed air which are directed downwards and entrain the lower free end of the web N towards the slot 3.
In order to guide the free end of the web N across the runway for the packages P and to cause it to enter smoothly and positively the lower outlet slot 103, the invention provides a vertical tubular web-guide member 11 which is substantially shaped as a flat sleeve or sheath having a rectangular cross section with a slightly flaring funnel-like upper end 111 and with a lower end (not shown) connected to a suction source. The guide member 11 is movable vertically and can be raised and lowered by any suitable guiding and actuating means, for example of the articulated parallelogram type or of the crank and connecting rod type. Specifically, the web-guide member 11 can be raised from a retracted position below the table 1 of the runway for the packages P, shown with full lines in Figure 1, through the lower outlet slot 103 to reach with its flared upper end 111 the upper inlet slot 3, as shown with dot-and-dash lines in Figure 1, and thereafter it can be lowered to its retracted initial position.
After a package P has been transferred, with the respective cellophane sheet F, into a cell 104 of the star--shaped operating wheel 4, the tubular web-guide member 11 reaches its uppermost position, before the lower free end of the web N emerges from the upper slot 3. The guide member 11, thus raised, will not hinder the return stroke of the pusher 5,105 to its initial position, inasmuch as the two halves of the pusher will move at both sides thereof, as described above. the lower free end of the web N, which comes out from the upper slot 3, enters the flared mouth 111 of the now raised guide member 11 and continues moving down within the tubular guide member 11 and thus crosses without getting jammed said runway and lower outlet slot 103. The jets of compressed air issuing from the holes 9,109 in the guide walls 8,108 and the suction through the tubular guide member 11 generate a descending flow of air ensuring a positive insertion of the lower free end portion of the web N into the flared mouth of the now raised guide member 11, thus avoiding any jibbing of said end portion of the web within said web-guide member 11. The guide member 11 is lowered to its retracted position below the bottom 1 of the runway by any suitable movement, even simultaneously with the descent of the web N into the guide member 11. Preferably, the guide member 11 reaches its retracted lowermost position below the bottom 1 before the web N has been completely lowered to the position where the sheet F is severed therefrom.
Obviously, the invention is not limited to the embodiment as above shown and described, but broad changes and modifications, especially of constructional nature, can be made thereto, and it can be used with any packaging machines, other than cellophaning machines, particularly with machines fed with any other type of wrapping or packaging materials and/or with previously-cut sheets, the whole without departing from the basic principles set forth above and claimed hereinafter.

Claims

1. A device for feeding webs or sheets (N,F) of packaging or wrapping material to packaging machines, wherein said web or sheet (N,F) is fed, usually in a vertical direction, across a runway (1) wherealong the articles (P) to be packaged are advanced, through an inlet transverse slot (3) in a wall, usually the upper wall, of said runway, and then through an outlet transverse slot (103) in the opposite wall, usually the lower wall, of said runway, so as to form a curtain which is engaged, bent into a U shape and dragged by the article to be packaged which is advanced along said runway by a pusher (5,105), characterized by a web- or sheet-guide member (11) which can be moved across said runway (1,2) where the articles P to be packaged are advanced and can be introduced through the outlet transverse slot (103) of said runway up to the inlet transverse slot (3) thereof, so as to receive the free end of the web (N) or sheet (F) coming out from the inlet slot (3) and to guide it down to and through the opposite outlet slot (103), where= after it withdraws from the runway (1,2) so that an article (P) to be packaged can be advanced past the curtain formed by the web or sheet which has been fed.

2. A feeding device according to claim 1, characte= rized in that said movable web- or sheet-guide member (11) is of tubular shape.

3. A feeding device according to claim 2, characte= rized in that said tubular web- or sheet-guide member (11) is connected to a suction source.

4. A feeding device according to claim 2, characte= rized in that said tubular web- or sheet-guide member (11) has a funnel-shaped flared mouth (111).

5. A feeding device according to claim 1, characte= rized in that said pusher which advances the articles (P) to be packaged along the advancement runway consists of two halves (5,105), which can be spaced from and approached to each other transversely to the advancement direction of the articles (P) to be packaged and transversely to the direction of feed of the web (N) or sheet (F) of packaging material, and which are actuated so that in their closed or approached position they push the article (P) to be packaged toward and past the curtain formed by the web (N) or sheet (F) which has been fed, and when separated and spaced from each other they are returned to their initial position along spaced paths round the two sides of the web- or sheet-guide member (11) which in the meantime has been inserted across the advancement runway.