Apparatus for the packaging of cigarettes by successively folding inner and outer wrappers about a hollow open-ended mandrel, plural of the mandrels being supported from a rotary turret which is moved in step-wise fashion, which enables the use of a metalized foil as the inner wrapper. The apparatus establishes communication between a low pressure source and the interior of the mandrel during at least a portion of the wrapper folding procedure with the resulting suction being applied to the inner wrapper via an open end of the mandrel and through an array of holes provided in the side of the mandrel where opposite free ends of the inner wrapper are positioned after folding.

BACKGROUND OF THE INVENTION 
(1) Field of the Invention 
The present invention relates to the packaging of articles and, 
particularly, to the formation of cigarette packages by successively 
folding inner and outer wrappers around pre-formed blocks of cigarettes. 
More specifically, this invention is directed to apparatus which forms a 
package by folding an outer wrapper about an article wrapped in a 
resilient inner wrapper and especially to apparatus which permits 
formation of such a package using, for the inner wrapper, a metalized foil 
material which has a tendency to return to its original sheet-like form 
when released by mechanical folding members of the packaging apparatus. 
Accordingly, the general object of the present invention are to provide 
novel and improved methods and apparatus of such character. 
(2) Description of the Prior Art 
While not limited thereto in its utility, the present invention is 
particularly well suited for use in apparatus known in the art as 
"bottom-folding packers" which are employed in the packaging of 
cigarettes. Such apparatus are characterized by a wrapping turret having 
plural hollow mandrels located in a geometric pattern, a star arrangement 
for example. Pre-formed blocks of cigarettes are disposed in the mandrels 
while inner and outer wrappers are folded thereabout. The wrapping turret 
will be driven, in step-wise fashion, with the steps comprising the 
spacing between wrapper folding stations. The apparatus is further 
comprised of feed devices for supplying both inner and outer wrappers, 
typically in sheet form, and stationery and moveable folding members for 
folding the inner wrapper around a mandrel and then for subsequently 
folding the outer wrapper around the folded inner wrapper. 
A "bottom-folding packer" of the type briefly described above, for 
producing so-called soft packs, is disclosed in published German patent 
application No. 3,046,063 and WO-80-00246. In the prior art apparatus, the 
inner wrapper has customarily been comprised of a laminate consisting of a 
paper coated with aluminum foil. In spite of the fact that the prior art 
bottom-folding packers do not produce sharp creases when the foil-coated 
paper is formed around the mandrel, the wrapper is nevertheless 
sufficiently deformed so that it generally retains its folded shape when 
released by the folding members of the packer. Such release of the inner 
wrapper is, of course, necessary in order to permit the addition of the 
outer wrapper to the partially formed package. 
The prior art inner wrapper materials are, when compared to metalized film, 
relatively expensive. It has, accordingly, for some time been desired to 
devise a manner in which a package having inner and outer wrappers could 
be formed employing a metalized film as the inner wrapper. Such efforts 
have previously been unsuccessful due to the fact that the metalized film 
is somewhat resilient and thus has a tendency to return to its original 
form when released by the mechanical folding members of the packer, i.e., 
unless mechanically restrained, the inner wrapper will spring away from 
the mandrel or other object about which it has been folded. 
SUMMARY OF THE INVENTION 
The present invention overcomes the above briefly-discussed and other 
deficiencies and disadvantages of the prior art and, in so doing, permits 
the use of metalized film as the inner wrapping of a package comprised of 
inner and outer wrappers. It is, accordingly, an object of the present 
invention to provide a bottom-folding packer suitable for use with 
metalized film inner wrappers. It is also an object of the invention to 
provide a packaging method wherein a resilient metalized film can be 
employed as an inner wrapping. 
The above objects of the invention are accomplished, in part, by the 
establishment of a low pressure zone which is in communication with the 
interior of the mandrels about which the inner and outer wrappers are 
folded. Accordingly, as the folding of the wrappers progresses, a 
pneumatic pressure differential is established across the inner wrapper. 
This pneumatic pressure differential will hold the folded ends of the 
wrapper in their folded positions. The pressure differential will be 
effective at least at the end of the mandrel opposite to that where the 
low pressure is applied and also at a side wall of the mandrel which 
corresponds to the final flap formed during folding of the inner wrapper. 
This side wall corresponding to the final formed flap will typically be 
the trailing wall in the direction of motion of the mandrel during the 
step-wise rotation of the turret on which it is mounted. 
In an embodiment wherein the low pressure zone is established in a duct 
connected to a vacuum source, that duct will extend over a sector of a 
circular ring. The duct will be provided, on the side which faces an open 
end of the mandrels, with an array of suction orifices which lie along the 
path of movement of the mandrels. The distance between these suction 
orifices will be less than the width of the mandrels whereby, once a 
mandrel has moved into operative registration with the duct, the open end 
thereof will remain in constant communication with the vacuum source until 
the folding operation is completed.

DESCRIPTION OF THE DISCLOSED EMBODIMENT 
Referring now to the drawing, the disclosed embodiment is designed for use 
in the packaging of cigarettes, indicated at 2, which have previously been 
formed into blocks. The packaging apparatus comprises a wrapping turret 1 
from which are supported a plurality of hollow open-ended mandrels 4. The 
pre-formed cigarette blocks are delivered into the mandrels 4 by means of 
a ram, not shown, which may be associated with a block turret, also not 
shown. The transfer of the blocks into the mandrels 4 will occur when a 
fully-loaded cell on the block turret is axially aligned with one of the 
mandrels 4, the mandrels 4 being provided with head-end mouth pieces 3, 
best seen in FIG. 2a, which guide the cigarette blocks into the mandrels 
4. The turret 1 is rotated, in the direction of arrow 12, in step-wise 
fashion during the wrapping process. 
A first sheet feed device, not shown, is positioned adjacent to the 
wrapping turret 1 for supplying an inner wrapper 5. Downstream, in the 
direction of rotation of turret 1, from the point at which the inner 
wrapper is supplied, a sheet-feed device 6 supplies the outer wrapper 7. 
By means of moveable folding members 8,9 and stationery folding members, 
only two of which 10,11 are partially shown, first the inner wrapper 5 and 
then the outer wrapper 7 are folded around the mandrel 4 so as to produce 
a package which is closed at the bottom, i.e., at the end opposite to the 
mandrel mouth piece 3. The thus partially formed package, together with 
the cigarette block located in the mandrel, will subsequently be pushed 
into a head-closing turret, not shown, where the package will be completed 
by closing the head end thereof. 
As noted above, during the wrapping procedure, the turret 1 is rotated by a 
stepping drive. This drive will move the mandrels a distance equal to one 
cell division for each step. Such step-wise turret drives are well known 
in the cigarette packaging art, as shown by the publications incorporated 
herein by reference, and thus will not be discussed further herein. 
The inner wrapper 5 will be supplied to the packer in the form of 
rectangular sheets of a metalized film. These sheets of inner wrapper are 
first pressed, by a cam-actuated folding arm 8 mounted on turret 1, 
against the side wall of the mandrel 4 which leads in the direction of 
rotation 12 of turret 1. Stationery folding members, not shown but similar 
to the stationery folding members 10 and 11 which act on the outer 
wrapper, will cause the inner wrapper 5 to pass about, and conform 
generally to the shape of, the two sides of the mandrel 4 which extend 
transversely from the opposite side edges of the leading side wall, i.e., 
the upper and lower walls of the mandrel 4 which extend generally counter 
to the direction of rotation. The wrapping 5 is, subsequently, folded 
against the trailing side wall of the mandrel, thus defining a pair of 
overlapping flaps 5' and 5". This last folding is accomplished by means of 
folding levers, not shown. Once the mechanical folding of the wrapper 5 in 
the manner described above has been completed, the cam-actuated arm 9 
mounted on turret 1 will move into position to capture the inner wrapper 5 
in the folded position thus preventing its inherent resiliency from 
causing the wrapper to unwrap. The above-described operation is 
schematically illustrated in FIGS. 3a and 3b. 
In order to form the bottom of the inner wrapper, referring again to FIG. 
3b, the portion 13 of the inner wrapper which projects beyond the bottom 
of the mandrel and which trails in the direction of rotation 12 is first 
folded downwardly in the direction of rotation by means of a folding 
member, not shown. Next, the projecting portion 14 at the leading edge 
will, by running into a stationery folding member, not shown, be folded 
downwardly over the wrapper portion 13, this folding being in a direction 
which is counter to the direction of rotation 12 of the turret. The upper 
and lower generally triangular-shaped tabs 15 produced by folding wrapper 
portions 13 and 14 are left extending outwardly as depicted in FIG. 3c 
while the outer wrapper 7 is applied. 
The folding arm 8 is retracted to enable the outer wrapper 7 to be 
positioned at the leading side of the mandrel over the inner wrapper 5. 
This results in the outer wrapper projecting beyond the top and bottom of 
the mandrel. The folding arm 18 is then reactivated to capture the outer 
wrapping 7 against the leading side of the mandrel. The mandrel then runs 
between the stationery folding members 10,11, shown partially, which fold 
the outer wrapper 7 around the inner wrapper 5 counter to the direction of 
rotation 12 of turret 1. Next, by means of two folding levers, not shown, 
the rearwardly projecting flap portions of the outer wrapper 7 are folded 
around onto the inner wrapper 5 thus producing the partial package 
depicted in FIG. 3d. 
Referring to FIG. 3e, while the outer wrapper is held down against the 
inner wrapper by means of the holding members 8 and 9, the outer wrapper 
bottom is folded by means of a pair of radially moveable folding thumbs, 
not shown, which simultaneously fold inwardly the underlying tabs 15 of 
the inner wrapper 5. Subsequently, the two remaining flaps of the outer 
wrapper bottom portion are folded over one another by means of folding 
members, not shown, to complete the wrapper folding operation and produce 
the product depicted in FIG. 3f. The folding members which produce this 
final closing operation will include one stationery member and one 
moveable member. 
In order to prevent the unfolding of the inner wrapper 5, as a consequence 
of its inherent resiliency, a low pressure is applied to the inside of the 
mandrels 4 beginning in the region where the inward folding of the bottom 
flap 13 of the inner wrapper occurs and continuing until the final fold of 
the bottom of the outer wrapper is completed. The low pressure is applied 
at the head end of the mandrels, i.e., via the mandrel mouth pieces 3. The 
low pressure is established in a duct 17 which is connected to a vacuum 
source via a connector 16. The duct 17 extends over a sector of a circular 
ring and is provided, on the side which faces the mandrels 4, with an 
arcuate array of suction orifices 18. The distance between adjacent 
orifices 18 is less than the width of the mandrels 4 and thus, while any 
given mandrel is in registration with the duct 17, low pressure will be 
continuously applied to the inside thereof. 
The mandrels 4 are provided with holes or perforations 19 in the side walls 
thereof which are trailing in the direction of rotation 12 of the turret 
1. Accordingly, when the mandrel reaches the position where the folding of 
the inner wrapper to define the bottom thereof is to be initiated, the 
interior of the mandrel is subjected to suction via orifices 18 with the 
low pressure being communicated to the bottom of the mandrel by means of 
the gaps between the cigarettes 2. Thus, the folded flaps 13,14, see FIGS. 
3b and 3c, will be kept in the folded position by the applied suction. 
Simultaneously, the suction exerted by the perforations 19 in the trailing 
side of the mandrel will keep the flaps 5' and 5" folded down against the 
mandrel 4 when the folding member 9 is retracted to permit the folding of 
the outer wrapper 5. As may be seen from FIG. 2a, the perforations 19 are 
appropriately arranged in two rows, located one above another, such that 
one row of perforations performs the function of retaining the flap 
portion 5' against the mandrel wall. The suction applied via the other row 
of perforations functions to retain the flap portion 5" against the 
mandrel. 
In order to minimize the capacity of the vacuum pump required for operation 
of the apparatus, cover plates 20 (FIG. 1) will typically be provided to 
overlie the suction orifices 18 which are located between adjacent of the 
mandrels 4, such suction plates moving with the turret. 
In one reduction to practice of the invention, the duct 17 was connected to 
a vacuum pump having a capacity of 180 m.sup.3 /h and a maximum vacuum of 
225 mbar was obtained. 
While a preferred embodiment has been shown and described, various 
modifications and substitutions may be made thereto without departing from 
the spirit and scope of the invention. Accordingly, it will be understood 
that the present invention has been described by way of illustration and 
not limitation.