GB2292726A

GB2292726A - Blank folding method for cigarette packets with bevelled edges

Info

Publication number: GB2292726A
Application number: GB9516501A
Authority: GB
Inventors: Giampaolo Parrocchetti; Claudio Mistroni; Antonio Gamberini
Original assignee: GD SpA
Current assignee: GD SpA
Priority date: 1994-08-31
Filing date: 1995-08-11
Publication date: 1996-03-06
Anticipated expiration: 2015-08-11
Also published as: ITBO940394A1; CN1053867C; GB2292726B; IT1274890B; ITBO940394A0; GB9516501D0; CN1125678A; DE19529798B4; DE19529798A1

Description

2292726 BLANK FOLDING METHOD FOR MACHINES FOR CONDITIONING TOBACCO ITEMS,

PARTICULARLY CIGARETTES, IN RIGID PACKETS WITH BEVELED LONGITUDINAL EDGES The present invention relates to a blank folding method for machines for conditioning tobacco items, particularly cigarettes, in rigid packets with beveled longitudinal edges.

US Patent n. 4,208,854 relates to a packing machine for conditioning cigarettes in rectangular-based packets, and wherein blanks with preformed longitudinal bend lines are fed, together with respective groups of cigarettes, to a folding device forming part of the machine and comprising a tubular folding spindle into which the groups of cigarettes are inserted successively. The folding spindle is coaxial with a movable pusher for supplying the groups of cigarettes, is aligned with a U-shaped pocket of a folding conveyor, and is located on the opposite side, in relation to the folding conveyor, of a line for supplying the blanks. Each blank is folded partly about the spindle and along the longitudinal bend lines by a shaped counter-pusher, which cooperates with the pusher to transfer each group of cigarettes and the respective partly-folded blank from the folding spindle to a respective pocket on the folding conveyor.

It is an object of the present invention to provide a method enabling a folding device substantially similar to the one described above, and of proven reliability, to be used for forming packets with beveled longitudinal edges.

According to the present invention, there is provided a blank folding method for machines for conditioning tobacco items, particularly cigarettes, in rigid packets with beveled longitudinal edges; each blank presenting preformed longitudinal bend lines defining two strips, and each strip corresponding to at least one respective beveled edge, and being defined by a respective outer and a respective inner bend line; characterized in that each blank is folded along its longitudinal bend lines in two steps, by first folding the blank along at least part of at least the outer bend line of each strip; and then folding the partlyfolded blank along at least part of at least the inner bend line of each strip.

Preferably, the blank is folded along at least part of said inner bend lines by feeding the partly-folded blank through a passage narrower than the distance between said outer bend lines.

According to a preferred embodiment of the above method, each blank is folded along said outer bend lines and simultaneously strain relieved along said inner bend lines.

Two non-limiting embodiments of the present invention will be described by way of example with reference to the accompanying drawings, in which:

Figure 1 shows a cross section of a first preferred embodiment of a folding device implementing the method according to the present invention; Figure 2 shows a detail of Figure I in different operating positions; Figure 3 shows a second embodiment of the Figure 2 detail in different operating positions.

Number 1 in Figure 1 indicates a folding device for folding blanks 2 fed to it successively in known manner, and forming respective rigid, hingedlid packets (not shown) with beveled longitudinal edges.

As shown in Figure 2a, known blank 2 presents two inner longitudinal bend lines 3 and 4 extending parallel to and on either side of the longitudinal axis 5 of blank 2, and which are separated by a distance D1 and define a central portion 6 of blank 2. Blank 2 also presents two outer longitudinal bend lines 7 and 8 extending parallel to and on either side of axis 5, separated by a distance D2 greater than D1, and defining on blank 2, together with respective adjacent bend lines 3 and 4, two strips 9, each of which corresponds to at least one beveled edge of the packet (not shown), and each of which defines, on blank 2, a respective outer longitudinal portion 10 on the opposite side of strip 9 in relation to central portion 6.

As shown in Figure 1, device 1 forms part of a packing machine (not shown) for conditioning tobacco items, in this case cigarettes, in rigid, hinged-lid packets with beveled longitudinal edges, and comprises a folding drum 11 rotated in steps about its central axis (not shown) to feed blanks 2 along a substantially circular path P together with respective groups 12 of cigarettes, each enclosed in a foil wrapping 13 and substantially in the form of a parallelepipedon with a substantially rectangular base.

Externally, drum 11 presents a number of radial pockets 14 (only one shown), each substantially U-shaped with its concavity facing outwards, and each fitted to drum 11 so as to close a respective radial opening 15 formed through drum 11.

Each pocket 14 is fed in steps by drum 11 through a transfer station 16 to receive a respective blank 2 and group 12, and comprises two numbers of opposed, substantially T-shaped blades direction substantially tangent to 11, from respective longitudinal either side of respective opening 11 bv screws 19. For each nocket 17 extending, in a the periphery of drum ribs 18 located on 15 and fitted to drum 14, blades 17 define two lateral surfaces 20, 21 facing each other at a distance between said distances D1 and D2 to define the - 5 inlet 22 of pocket 14; and a bottom surface 23 crosswise to surfaces 20, 21 and presenting a central opening 24. Device 1 also comprises a tubular folding spindle 25 for housing a group 12, and which is supported, by a pair of brackets 26, in a fixed position outwards of drum 11 and coaxial with a pocket 14 arrested in station 16; and a transfer device 27 movable through station 16 in a radial direction 28 to successively feed each group 12 from spindle 25 into a respective pocket 14 together with a respective blank 2 fed, in use, to station 16 by a known feed device (not shown) by which blank 2 is positioned between pocket 14 and spindle 25, with its central portion 6 facing spindle 25.

Spindle 25 comprises a frame 29 substantially in the form of a rectangular parallelepipedon, and presenting an axis 30 parallel to direction 28. More specifically, frame 29 comprises two long longitudinal walls 31, 32 parallel to the axis of drum 11, to ribs 18, and to direction 28, and presenting respective inner surfaces 33, 34 parallel to each other, and facing each other at a distance substantially equal to the crosswise dimension of group 12 and between distances D1 and D2. Walls 31, 32 are defined externally by respective surfaces 35, 36 converging towards drum 11; and frame 29 also comprises two short transverse walls 37 (only one shown) crosswise to walls 31, 32, separated by a distance substantially equal to the longitudinal dimension of group 12, and defining, with walls 31, 32, a passage 38 with a section approximately equal to but no smaller than the longitudinal section of group 12, and approximately equal to but no larger than the cross section of the cavity defined by a pocket 14.

As shown in Figure 2, on the side facing station 16, walls 31, 32 are defined by respective flat end surfaces 39, 40 parallel to ribs 18 and forming, With respective surfaces 35, 36, respective edges 41, 42 separated by a distance substantially equal to distance D2 between bend lines 7 and 8.

Loading device 27 comprises a pusher 43 located outside drum 11, presenting a push plate 44 crosswise to direction 28, and which is moved back and forth in direction 28, in relation to drum 11, and through spindle 25 by known actuating means (not shown); and a counter-pusher 45 coaxial with pusher 43 and axis 30, and which is moved back and forth in direction 28 through pocket 14 and respective opening 15 by known actuating means (not shown) when pocket 14 is located, in use, at station 16.

Counter-pusher 45 comprises a push head 46 defined by two numbers of opposed, substantially L-shaped folding blades 47 extending in opposite directions from the opposite lateral edges of a central element 48 for loosely engaging opening 24. More specifically, each blade 47 is so located and sized as to pass, in use, between two blades 17 when counterpusher 45 is moved through opening 15 and pocket 14 in station 16.

Blades 47 make head 46 into a substantially U-shaped body with its concavity facing spindle 25, and defined internally by a folding surface 49 substantially complementary to the outer shape of spindle 25.

More specifically, surface 49 comprises a central portion 50 perpendicular to axis 30; and two lateral portions 51 and 52 substantially parallel to respective surfaces 35 and 36. With portions 51 and 52, portion 50 forms respective inner edges 53 and 54 parallel to edges 41 and 42 and separated by a distance approximately equal to but no less than distance D2.

Operation of device 1 will now be described as of the instant in which a blank 2 is fed into station 16, between spindle 25 and a respective pocket 14 in station 16, and, by means of known positioning and stop means (not shown), is arrested facing surfaces 39 and 40 with outer bend lines 7 and 8 respectively facing edges 41 and 42; and, at the same time, a respective group 12 is fed by pusher 43 into spindle 25.

At this point, counter-pusher 45 is moved towards spindle 25, so that blades 47 pass between blades 17, and central element 48 passes through central opening 24 of pocket 14. As counter-pusher 45 moves forward, portions 51 and 52 of surface 49 of head 46 gradually contact outer longitudinal portions 10 of blank 2 to fold blank 2 about surfaces 35, 36, 39 and 40 of spindle 25, and more specifically, partially fold portions 10 in relation to portion 6 and about outer longitudinal bend lines 7 and S.

As shown in Figure 2c, when counter-pusher 45 terminates its travel, outer longitudinal portions 10 are positioned fully contacting respective portions 51 and 52 of surface 49, and strips 9 are positioned contacting surfaces 39 and 40 and the surface 55 of group 12 facing counter-pusher 45 and coplanar with surfaces 39 and 40. At this point, pusher 43 and counter-pusher 45 are moved together towards pocket 14 so as to withdraw group 12 and partially-folded blank 2 from spindle 25 and feed them into pocket 14. Since, as already stated, the distance between surfaces 20 and 21 of pocket 14 is less than distance D2, i. e. less than the distance between the outer longitudinal bend lines 7 and 8 of blank 2, when blank 2 partially folded at bend lines 7 and 8 is inserted into pocket 14, it is further folded at inner longitudinal bend lines 3 and 4., so that portions 10 are positioned parallel to each other and contacting respective surfaces 20 and 21, and strips 9 are inclined substantially 4511 in relation to adjacent portions 10 and 6. As shown in Figure 1, the folding of strips 9 into the above inclined position is assisted by lead- in bevels 56 formed at the input edges of surfaces 20 and 21 and such that the width of inlet 22 of pocket 14 substantially equals distance D2.

Device 1 therefore provides for forming beveled edges by folding blank 2 in two successive stages, in the first of which, it is folded along outer longitudinal bend lines 7 and 8, and in the second of which, it is folded along inner longitudinal bend lines 3 and 4. Moreover, blank 2 is folded as described using a folding device 1 substantially identical to the corresponding folding device described in US Patent n. 4,208,854 referred to previously, and from which device 1 differs substantially only in terms of size.

In other words, beveled-edged packets (not shown) may be formed by simply adjusting the size of a small number of parts of a standard packing machine (not shown) for producing rigid, rectangu 1 ar -based packets, thus enabling the same standard packing machine (not shown), with only relatively minor dimensional changes, to be used for producing both rigid, rectangular-based and rigid, beveled-edged packets.

The Figure 3 embodiment relates to a folding device 57 similar to device 1, except that surfaces 39 and 40 are dispensed with, and surfaces 33 and 34 form, with surfaces 35 and 36, respective sharp edges 58 and 59 separated by a distance between D1 and D2.

Consequently, as blank 2 is engaged gradually by counter-pusher 45 (Figure 3b), portions 10 are folded about outer longitudinal bend lines 7 and 8, and, at the same time, blank 2 is strain relieved along inner longitudinal bend lines 3 and 4; which strain relieving, which is later removed (Figure 3c) upon spindle 25 contacting central portion 50 of surface 49 of head 46, assists subsequent folding of blank 2 along bend lines 3 and 4 when blank 2 is inserted inside pocket 14.

Claims

1) A blank folding method for machines for conditioning tobacco items, particularly cigarettes, in rigid packets with beveled longitudinal edges; each blank presenting preformed longitudinal bend lines defining two strips, and each strip corresponding to at least one respective beveled edge, and being defined by a respective outer and a respective inner each blank lines bend line; characterized in that is folded along its longitudinal bend in two steps, by f irst folding the blank along at least part of at least the outer bend line of each strip; and then folding the partly-folded blank along at least part of at least the inner bend line of each strip.

2) A method as claimed in Claim 1, characterized in that the blank is f olded along at least part of said inner bend lines by feeding the partly-folded blank through a passage narrower than the distance between said outer bend lines.

. characterized is folded along said outer bend by first bringing each said strip into contact with a support. and folding a portion of the blank, located outwards of each outer 3) A method as claimed in Claim 2 in that each blank lines bend line, in relation to the central portion of the blank located between said inner bend lines.

4) A method as claimed in Claim 3, characterized in that the support for each said strip is defined by a respective edge of a tubular folding spindle coaxial with said passage.

5) A method as claimed in Claim 4, characterized in that said edges are defined by respective flat surfaces presenting respective outer edges separated by a distance substantially equal to said distance (D2) between the outer bend lines.

6) A method as claimed in Claim 1 or 2, characterized in that each blank is folded along said outer bend lines and simultaneously strain relieved along said inner bend lines.

7) A method as claimed in Claim 6,characterized in that each blank is folded along said outer bend lines by first bringing each said strip into contact with a support defined by a respective edge of a tubular folding spindle coaxial with said passage, and folding a portion of the blank. located outwards of each outer bend line, in relation to the central portion of the blank, located between said inner bend lines; said edges being separated by a distance between the distance (D2) between said outer bend lines, and the distance (D1) between said inner bend lines.

8) A blank folding method for machines for conditioning tobacco items, in particular cigarettes, in rigid packets with beveled longitudinal edges, substantially as described and illustrated herein with reference to the accompanying drawings.