[0001] The present invention concerns a method and a machine for packaging different objects,
particularly bottles, allowing to obtain a packing meant for hand transport by the
buyer. The invention also concerns the portable packing obtained with said method.
[0002] It is known that, for packaging bottles for retail sales, use has been made for several
decades of returnable wooden or plastic boxes containing a dozen of bottles. Such
a solution involves different drawbacks, as a high cost, the requirement of a service
to return the empties (empty bottles as well as empty boxes), a great waste of space
even when the box is empty, as well as a heavy weight when it is filled with bottles
such as to make it difficult for most buyers to carry it by hand.
[0003] To replace the boxes, smaller packings have recently been proposed, comprising for
example six one- or two-litre bottles arranged on two rows of three side-by-side bottles,
held together by a film of thermoretractible plastic material. With this solution,
packaging costs have been notably lowered, the need to return the empties has disappeared,
and the weight of each packing has been reduced to an extent such as to make it hand
transportable even for fairly long distances.
[0004] Nevertheless, these packings of thermoretractible plastic material are still not
considered fully satisfactory, on one hand because of their cost and on the other
hand due to actual transport difficulties. In fact, owing to its reduced weight, the
packing could be easily carried with a single hand, but since it lacks adequate gripping
means, it has to be forcedly carried using both hands, thereby depriving the buyer
of that freedom of movement which is essential to allow him to easily do the shopping
and carry the bags.
[0005] To overcome these drawbacks, it has recently been proposed to supply packings, equally
consisting of a closed film of thermoretractible plastic material, but provided with
a gripping handle formed of a plastic strip surrounding the packing itself. This solution
has however the fundamental drawback of requiring additional packaging elements which,
beyond their intrinsic cost, also involve an additional cost for their application.
Furthermore, the plastic strip - due to its modest transversal dimensions - can easily
"cut through" the packing and cause unpleasant and painful sensations to the hand
carrying the same.
[0006] Still more recently, packings have been proposed which consist of two intersecting
wrapping films of plastic stretching material, one of which - and precisely the wrapping
extending in the vertical plane - is meant to form also a gripping handle. These packings
are described for example in US-A-4,304,332 and in US-A-4,596,330, as well as in the
Italian Patent Application No. 21.483 A/89 in the name of the same Applicant. Nevertheless,
the packings described in all these patents still involve at least two drawbacks:
- On one hand, the wrapping meant to form the handle, and thus extending on a vertical
plane, involves considerable packaging problems: in fact, since said wrapping extends
under the bottom of the bottles, these need to be kept lifted from their respective
bearing surface while the wrapping is being applied thereon. To do so, one should
thus first form the wrapping on a horizontal plane so as to tighten together the bottles
into a single block; said block of bottles is then gripped on the side so as to be
lifted and allow forming the second wrapping on the vertical plane.
- On the other hand, when gripping the wrapping which forms the handle - consisting
of a film of plastic stretching material - this latter tends to loosen during transport,
under the weight of the bottles. Seen the nature of this plastic material, the longer
the carrying distance the more the handle stretches out, and the more it stretches
out the narrower it gets, thereby producing both an unpleasant cutting sensation on
the hand carrying the same, and a loosening of the wrapping such as to cause its misplacement
or even its slipping off from the block of bottles, with further transport difficulties.
[0007] The object of the present invention is to therefore propose a packing - of the heretofore
mentioned type, formed of two intersecting wrappings, one extending on the horizontal
plane and the other on the vertical plane, the vertical wrapping forming also gripping
means for the packing, in the form of a handle - which is even more improved in respect
of those described in the above indicated patents.
[0008] More precisely, a first object of the invention is to provide a packing of the aforecited
type, wherein the vertical wrapping, forming the gripping handle, shows improvements
both for what concerns the comfort for the hand carrying the packing and for what
concerns its transport resistance.
[0009] A further object of the invention is to obtain a packing of the aforecited type,
wherein the vertical wrapping holds more tightly and more reliably onto the group
of bottles.
[0010] According to the invention, these results are achieved with a method for packaging
a group of objects, particularly a group of bottles, essentially characterized in
that,
- to start with, the wrapping on the vertical plane is formed by feeding a first length
of strap from the top over the group of objects and a second length of strap from
the bottom under said objects, and by then joining together the leading and, respectively,
the tail ends of the two strap lengths;
- subsequently, a second wrapping is formed on the horizontal plane using a strap of
plastic stretching film, which is wound into several turns over the first wrapping
so as to tighten it and block it against the group of objects; and
- said first strap length of the vertical wrapping is finally gathered up at the top
so as to form a gripping handle.
[0011] It is thus possible, according to the invention, to select the material forming the
first strap length, so that its characteristics may be particularly suited to form
a gripping handle, while the material of the second strap length can be selected so
as to have the best properties for adhering onto the block of objects.
[0012] More precisely, and according to a preferred embodiment of the invention, the first
strap length will consist of a flexible plastic material with high tensile strength,
such as a polyethylene film having a thickness of 60/70 µm.
[0013] Also according to a preferred embodiment of the invention, the second strap length
will consist of a commercial type adhesive tape, of polyvinylchloride (PVC) or polypropylene,
applied with its adhesive surface facing upward, so as to adhere to the bottom of
the objects, and allow the leading and tail ends of the straps to be joined together
by simple adhesion of the ends of the second strap length onto the ends of the first
strap length.
[0014] Further characteristics and advantages of the packaging method, machine and packing
according to the invention will anyhow be more evident from the following detailed
description of some preferred embodiments thereof, given by way of example and illustrated
on the accompanying drawings, in which:
Fig. 1 is a diagrammatic perspective view of a group of six bottles onto which a first
wrapping has been applied, consisting of a film of flexible plastic material extending
on the vertical plane and designed to form a gripping handle;
Figs. 2, 3 and 4 show diagrammatically how to form said first wrapping;
Fig. 5 is a view similar to fig. 1, showing how to apply the second wrapping consisting
of the film of plastic stretching material;
Fig. 6 is a diagrammatic plan view, with some removed parts, showing the packing after
the second wrapping has been completed;
Figs. 7, 8 and 9, show how to form the gripping handle with the first wrapping and
how to carry the packing; and
Fig. 10 is a diagrammatic perspective view, showing in further detail the mechanical
elements of a working station in which the first vertical wrapping is formed.
[0015] The packaging method according to the invention is first of all described with reference
to figures 1 to 9, showing only a trace of the machine to carry out said method. The
working station of said machine, in which the vertical wrapping is formed, is subsequently
described in further detail with reference to figure 10.
[0016] It has to be pointed out that the packaging machine illustrated on the accompanying
drawings and described hereinafter is designed for a packing of six bottles. It is
however understood that the description of said machine is given by mere way of example
and should in no way be interpreted as limiting the protection scope of the invention,
which can instead be generally applied to any other type of packaging machine allowing
to obtain a packing in the form of two intersecting wrappings consisting of a film
of plastic material.
[0017] As shown in figure 1, a first wrapping extending on a vertical plane is formed on
a group of objects to be packaged, particularly a group of six plastic bottles B positioned
side-by-side in two rows of three; said wrapping is formed in two parts and, precisely,
an upper strap 1 and a lower strap 2, joined together.
[0018] Figure 2 shows how the two straps 1 and 2 are fed, starting from two respective feed
rolls 1a and 2a, to a packaging machine having a sliding surface in the form of rollers
3 and a closing and cutting tool 4.
[0019] At the start of the packaging operation, the two straps 1 and 2 are joined together
by their ends, in U. This connection is obtained by glueing, thermowelding, or the
like, as better specified hereinafter.
[0020] As it appears evident from the sequence of figures 2 and 3, the bottles B - moving
forward on the surface 3 in the direction F - bear against the two joined straps 1
and 2 (fig. 2) and drag them forward (fig. 3) so as to allow forming a vertical wrapping,
which initially covers the right side (in respect of the drawing) and the upper and
lower sides of the group of bottles B.
[0021] When the bottles have reached a position (fig. 3) beyond the cutting tool 4, this
latter is moved down - as shown in figure 4 - so as to cut the straps 1 and 2. While
cutting, the tool 4 also provides to stick together, on one side, the ends 1′ and
2′, so as to complete the wrapping and close the packing and, on the other side, the
ends 1˝ and 2˝, so as to allow the next packaging operation. In this way, a first
wrapping of the group of bottles, extending on the vertical plane, has been completed
as shown in figure 1. The operation of the cutting tool 4 is described in further
detail with reference to figure 10.
[0022] The upper strap 1 of said first wrapping preferably consists of a film of flexible
plastic material, as for instance polyethylene, having a thickness of 60/70 µm.
[0023] According to a preferred embodiment of the invention, the lower strap 2 is instead
an adhesive tape of commercial type, for example a polyvinylchloride (PVC) or polypropylene
tape with one of the surfaces having a layer of adhesive substance. The use of this
strap provides a double advantage:
- on one hand, it facilitates joining the two ends of the straps 1 and 2 when closing
the vertical wrapping, so that the tool 4 must simply cut and stick the adhesive tape;
- on the other hand, the strap 2 adheres also to the bottom of the objects being packaged
- particularly the bottom of the bottles B - thereby helping to keep said objects
firmly positioned in the packing and, at the same time, guarantee the fastening of
the vertical wrapping.
[0024] According to a different embodiment of the invention, it is of course possible for
the lower strap 2 to be equally formed of a polyethylene film - like the upper strap
- and to be anchored onto the strap 1 by glueing or thermowelding. In this last case,
the tool 4 will obviously be provided with thermowelding means.
[0025] The packaging method then provides for a further step wherein a second wrapping is
formed, using a strap which extends on the horizontal plane, as shown in figure 5.
Said second wrapping 5 consists of a film of plastic stretching material - as PVC,
EVA (ethylvinylacetate), LPDE (low density polyethylene) and, above all, LLPDE (low
density linear polyethylene) - wound into several turns over the first wrapping 1-2.
This second wrapping is applied under slight tension, so as to positively block in
position both the packed objects and the vertical wrapping.
[0026] Figure 6 shows how the second wrapping 5 keeps the first wrapping 1-2 strongly tightened
against the lateral surface of the bottles, and thus forms an integrating part of
the packing. Practical tests have shown that this tightening action is sufficient
to keep fastened the strap 1 of the first wrapping even if the strap 2, and thus the
respective anchorage, should be missing.
[0027] In the final step of the packaging method according to the invention - shown in figures
7 to 9 - a gripping handle 6 is formed by gathering up the strap 1 at the top of the
vertical wrapping.
[0028] Referring now to figure 10 - which, as said, shows in further detail the working
station in which the vertical wrapping is formed - it can be seen that the bottles
B1, sent from a bottling line and advancing in a vertical position onto a sliding
surface - for instance the already mentioned rollers 3, or a horizontal belt conveyor
(not shown) - are divided into groups of six, each group being stopped in succession
in the different working stations of the packaging machine, and precisely the stations
supporting the groups of bottles B1A, B1B, B1C and respectively B1D (of which only
station B1B is shown to form the vertical wrapping).
[0029] In the working station B1B, as shown in figure 10, the lower strap 2 - preferably,
as said, an adhesive tape - is unwound from a feed roll 2a, by way of a motored unwinding
roller 9, and is fed onto the horizontal sliding plane of the bottles with its adhesive
surface facing upward, so as to come into contact with the bottom of the bottles B1B.
[0030] The upper strap 1 - preferably, as said, a film of strong and flexible plastic material,
of the PVC or polypropylene type - is unwound from a feed roll 1a and moves first
of all across a set of driving rollers 10, meant to develop a length of film so as
to facilitate unwinding, and subsequently across a cutting and applying head 11, movably
mounted along vertical guides (not shown).
[0031] The head 11 is formed of a stiff body, ending at the bottom with an oblique surface
11a. A cutter 12, to cut the strap, is fixed on the side opposite to the surface 11a.
A sliding block 13 is moreover positioned against the cutter 12 for protection thereof,
said block being mounted vertically slidable - against the action of spring means
14 - between a lowered position protecting the cutter 12 (shown in figure 10) and
a raised position in which the cutter is free to cut the straps 1 and 2 (as better
described hereinafter). The sliding block 13 has in turn an oblique surface 13a, opposite
to the surface 11a and forming therewith a kind of wedge.
[0032] A counterhead unit is mounted beneath the horizontal sliding plane of the bottles,
said unit consisting of a U clip 17 mounted on a support 18 moving vertically under
the action of a piston 19. The clip 17 is formed of a flat spring, the arms of which
tend to open wide apart due to elasticity and, in a rest position, they bear onto
a pair of fixedly mounted guide bars 20.
[0033] When the vertical wrapping is formed in the working station B1B, the head 11 is moved
down from the rest position shown in figure 10, in the direction of the arrow F3,
carrying with it the strap 1 down to the position indicated by the dash-and-dot line
1′. As can be seen from the drawing, the strap 1 bends at the bottom taking up a wedge
profile, which corresponds to its bearing onto the oblique surfaces 11a of the head
11 and 13a of the sliding block 13.
[0034] At the end of the downstroke of the head 11, the sliding block 13 is raised, leaving
the cutter 12 free to cut the strap 1. The two strap ends, thus cut, move away from
the surfaces 11a and 13a, and are applied - for example by an air jet blown by nozzles
(not shown) -against the side of the bottles of the group B1B and, respectively, against
a bearing plate 11′ fixed to the body of the head 11 (said bearing plate 11′ being
at this stage adherent to the side of the bottles of the group B1A).
[0035] At the same time, the support 18 is moved upward together with the clip 17, the arms
of which press first of all the strap 2 against the cutter 12, up to causing its cutting.
As the clip 17 moves up even further, its arms, being released from the bars 20, then
open elastically wide apart and press the cut ends of the strap 2 against the side
of the bottles B1B and, respectively, against the plate 11′, that is, over the ends
of the strap 1 (which were already bearing on said surfaces) onto which they stick.
[0036] This application of the adhesive surface of the strap 2 onto the strap 1 produces
a permanent connection between the two straps: this allows to close the vertical wrapping
on the side of the group of bottles B1B, and to form the initial junction for a new
wrapping - like the U junction on the group of bottles B1B - on the side of the group
of bottles B1A. The bottles can thus be moved forward towards the third working station,
taking up the position of the group of bottles B1C, while their place is taken by
the group of bottles B1A positioned further upstream, which, in its forward motion,
draws the required length of reciprocally joined straps 1 and 2, as described with
reference to figure 3.
[0037] As already briefly mentioned, the main advantages of the packaging method according
to the invention are:
- on one hand the fact that, by forming the vertical wrapping with two distinct and
separately fed strap lengths, it is possible to select the material for each strap
independently and thus with the properties most suited for the functions of each strap
length;
- in particular, the material selected for the upper strap length will have to be strong,
so as not to loosen during transport, and smooth, so as to provide the necessary comfort
for the hand, while the material selected for the lower strap length will have to
be strong and, at the same time, apt to adhere to the bottom of the bottles;
- on the other hand the fact that, this packaging method allows to apply the vertical
wrapping in the first place, without having to lift the group of bottles (which is
practically impossible, according to prior art, seen that there is nothing to hold
the bottles together);
- finally the fact that, by applying the horizontal wrapping in the second place, this
latter is apt to tighten and retain the vertical wrapping, preventing it from accidentally
slipping off.
[0038] It is anyhow understood that the invention is not limited to the particular embodiments
described heretofore, which are merely examples not limiting the scope thereof, but
that several modifications can be introduced, all within reach of an expert of the
art, without thereby departing from the protection scope of the invention itself.
1) Method for packaging a group of objects, particularly a group of bottles, allowing
to obtain a portable packing, wherein said group of objects is wrapped with two intersecting
wrappings consisting of straps of plastic material, one of the wrappings extending
on the vertical plane and forming also a gripping handle, characterized in that,
- to start with, the wrapping on the vertical plane is formed by feeding a first length
of strap from the top over the group of objects and a second length of strap from
the bottom under said objects, and by then joining together the leading and, respectively,
the tail ends of the two strap lengths;
- subsequently, a second wrapping is formed on the horizontal plane using a strap
of plastic stretching film, which is wound into several turns over the first wrapping
so as to tighten it and block it against the group of objects; and
- said first strap length of the vertical wrapping is finally gathered up at the top
so as to form a gripping handle.
2) Method as in claim 1) wherein said first length of strap is made of a polyethylene
film having a thickness of 60/70 µm.
3) Method as in claim 2) wherein said second length of strap is made of a commercial
type adhesive tape, which is applied with its adhesive surface facing upward, so as
to adhere to the bottom of the objects and allow the leading and tail ends of the
two straps to be joined together by simple adhesion of the ends of the second strap
length onto the ends of the first strap length.
4) Method as in claim 2), wherein said first and second strap lengths each consist of
a film of thermoweldable plastic material, and wherein the leading and tail ends of
said strap lengths are joined together by thermowelding.
5) Machine for packaging a group of objects, particularly a group of bottles, allowing
to form a portable packing by means of at least one wrapping consisting of a strap
of plastic material extending in the vertical plane, so as to carry out the method
according to claim 1), said machine comprising means to feed from the top a first
wrapping strap, means to feed from the bottom a second wrapping strap, means to cut
a first and a second strap length from said strap fed from the top and, respectively,
from the strap fed from the bottom, and means to join together the leading and, respectively,
the tail ends of said strap lengths.
6) Machine as in claim 5), wherein the top feeding means comprise a vertically movable
feeding and cutting head.
7) Machine as in claim 6), wherein the carrying end of said head has a double-wedge
configuration, a first part of the wedge being fixed and carrying a cutter and a second
part being formed as a sliding block apt to protect said cutter.
8) Machine as in claim 7), wherein the bottom feeding means comprise a counterhead,
apt to cooperate with the top feeding head at the end of its downstroke feeding the
strap, the counterhead being in the form of a U clip with spring arms.
9) Machine as in claim 8), wherein the counterhead is vertically movable towards the
feeding and cutting head, at the end of said movement the spring arms of said U clip
opening elastically wide apart, so as to press onto the facing ends of the upper and
lower strap lengths and join them together.
10) Portable packing for a group of objects, particularly a group of bottles, comprising
two intersecting wrappings consisting of straps of plastic material, a first wrapping
extending in the vertical plane and being gathered at the top so as to form gripping
means in the form of a handle, and a second wrapping extending in the horizontal plane,
characterized in that,
- said first wrapping consists of two strap lengths, a first length extending over
the top of the group of objects and a second length extending under the bottom thereof,
the leading and, respectively, the tail ends of the two strap lengths being joined
together, one on top of the other, and in that,
- said second wrapping consists of a strap of plastic stretching material wound into
several turns over the first wrapping and tightening this latter against said group
of objects.
11) Portable packing as in claim 10), wherein said first strap length, extending over
the top, consists of a polyethylene film having a thickness of 60/70 µm.
12) Portable packing as in claim 10), wherein said second strap length, extending under
the bottom, consists of a commercial type polyvinylchloride or polypropylene adhesive
tape.
13) Portable packing as in claim 10), wherein said group of objects consists of a group
of six bottles positioned on two rows of three side-by-side bottles.