U.S. patent application number 10/543458 was filed with the patent office on 2006-03-16 for method and a system for wrapping objects and use of the method.
Invention is credited to Poul Blom Petersen.
Application Number | 20060053750 10/543458 |
Document ID | / |
Family ID | 32892823 |
Filed Date | 2006-03-16 |
United States Patent
Application |
20060053750 |
Kind Code |
A1 |
Petersen; Poul Blom |
March 16, 2006 |
Method and a system for wrapping objects and use of the method
Abstract
The invention involves a method and a system and use of the
method for wrapping one or more objects (6) in stretch film, said
film (1) comprising a tube-like section, the diameter of which is
smaller than the diameter of the object or objects to be wrapped,
said film comprising a first end (2) and a second opposite end (4),
wherein the film is opened at its first end and provided with a
number of folds transversally of its longitudinal axis, following
which the film is expanded diametrically. Novel aspects comprise
that the object or objects are supported and advanced essentially
horizontally or under a flat angle in relation to the horizontal
into the expanded film from the first free end thereof towards the
second end of the film, which other end is closed, following which
the film is pulled around the object or objects the folds of the
film being unfolded, until the entire object or objects is/are
introduced into the film, following which the first end of the film
is closed by joining for complete enclosure of the object or
objects in the film. Hereby, compared to the prior art, it is
accomplished that the object or objects is/are enclosed on all
sides and hence completely.
Inventors: |
Petersen; Poul Blom; (Varde,
DK) |
Correspondence
Address: |
PITNEY HARDIN LLP
7 TIMES SQUARE
NEW YORK
NY
10036-7311
US
|
Family ID: |
32892823 |
Appl. No.: |
10/543458 |
Filed: |
February 21, 2004 |
PCT Filed: |
February 21, 2004 |
PCT NO: |
PCT/DK04/00115 |
371 Date: |
July 26, 2005 |
Current U.S.
Class: |
53/441 ; 53/459;
53/556; 53/567 |
Current CPC
Class: |
B65B 9/14 20130101; B65B
9/135 20130101 |
Class at
Publication: |
053/441 ;
053/459; 053/556; 053/567 |
International
Class: |
B65B 53/00 20060101
B65B053/00; B65B 43/26 20060101 B65B043/26 |
Claims
1. A method of wrapping one or more objects (6) in stretch film,
which film (1) comprises a tube-like section, the diameter of which
is smaller than the diameter of the object or objects (6) to be
wrapped, which film (1) comprises a first end (2) and a second
opposite and closed end (4), wherein the film (1) is opened at its
first end (2) and provided with a number of folds transversally of
its longitudinal axis, following which the film (1) is expanded
diametrically, wherein the object or objects (6) is/are conveyed by
roller paths and/or conveyor belts (12, 14), essentially
horizontally or under a flat angle in relation to the horizontal,
into the expanded film (2) from its first end (2) towards the
second end (4) of the film, following which the film (1) is pulled
around the object or objects (6) as the folds of the film are
unfolded, until the entire object or objects (6) have been
introduced into the film (1), following which the first end (2) of
the film is closed by joining for complete enclosure of the object
or objects in the film, characterized in that the film (1) is,
during advancement of the object or objects (6) in the film,
arranged at a space between the first (12) and the second (14)
roller paths and/or conveyor belts, and wherein the object or
objects are conveyed from the first (12) to the second (14) roller
paths and/or conveyor belts.
2. A method according to claim 1, characterized in that the object
or objects (6) are arranged on the first roller paths and/or
conveyor belts (12) and seized by seizing means, following which
the object or objects are introduced into the film (1) and arranged
on the other roller paths and/or conveyor belts (14), following
which the object or objects are let go.
3. A method according to claim 1, characterized in that the first
roller paths and/or conveyor belts (12) is displaceable or
comprises a displaceable section (15), wherein the first roller
paths and/or conveyor belts (12) or section (15) is displaced and
introduced into the expanded film (1) for further supporting the
object or the objects (6) during movement from the first (12) to
the second (14) roller paths and/or conveyor belts.
4. A method according to claim 1, characterized in that the film
(1) is tensioned for tightening when being pulled around the object
or objects (6).
5. A method according to claim 4, characterized in that the
tensioning imparts a permanent increase in length to the film
(1).
6. A method according to claim 3, characterized in that the section
(15) comprises roller paths and/or conveyor belts.
7. A method according to claim 1, characterized in that the joining
is accomplished by welding.
8. A method according to claim 1, characterized in that the object
or objects (6) are arranged on a carrier means such as a
pallet.
9. A method according to claim 1, characterized in that the film
(1) is dispensed from a storage unit (8), from where it is cut to a
suitable length and closed at its second end (4) by joining prior
to folding.
10. A method according to claim 9, characterized in that the film
(1) on the storage unit (8) is provided with longitudinally
extending folds that reduce the width of the film.
11. A system of exercising the method according claim 1, wherein
one or more of the objects (6) are wrapped in stretch film, said
film (1) comprising a tube-like section, the diameter of which is
smaller than the diameter of the object or objects (6) to be
wrapped, which film (1) comprises a first end (2) and an opposite
and closed end (4), wherein the system comprises means for opening
(22) the film at its first end and means for moving (20, 22) the
film across a hollow stretching unit (10) and providing the film
with a number of folds transversally of its longitudinal axis, said
stretching unit (10) comprising means for expanding the film
diametrically and means for forming holding-back means (20) while
the film is being released, wherein the system comprises roller
paths and/or conveyor belts (12, 14) for conveying, essentially
horizontally or under a flat angle in relation to the horizontal,
the object or objects (6) through the stretching unit (10) with the
film (1) in expanded state for pulling the film (1) around the
object or objects (6) and completely introducing it or them into
the film (1), and means for closing and joining (16) the first end
(2) of the film for complete enclosure of the object or objects (6)
in the film characterized in that said roller paths and/or conveyor
belts (12, 14) comprise a first (12) and a second (14) roller paths
and/or conveyor belts, wherein the film (1), during the conveying
of the object or objects (6) in the film, is arranged at a space
between said first and a second roller paths and/or conveyor belts
(12, 14), and wherein the object or objects are conveyed from the
first (12) to the second (14) support.
12. A system according to claim 11, characterized in that the first
support (12) is displaceable or comprises a displaceable section
(15), wherein the first support (12) or section (15) is displaced
and introduced into the expanded film (1) for further supporting
the object or the objects (6) during the conveying from the first
(12) to the second support (14).
13. A system according to claim 11, characterized in that said
displaceable section (15) comprises roller paths and/or conveyor
belts.
14. A system according to claim 11, characterized in that the
system comprises means for dispensing film from a storage unit
(8).
15. A system according to claim 11, characterized in that the
system comprises means for welding (16) and means for cutting off
(18) the film, said means being displaceable and arranged after the
stretching unit (10).
16. A system according to claim 11, characterized in that the
stretching unit (10) comprises operated rollers (20) for winding of
film (1), said rollers forming holding-back means when film is
pulled around the object or objects (6).
17. A system according to claim 16, characterized in that the
rollers (20) comprise means for measuring angulation, including
encoders.
18. The method according to claim 1, wherein said objects (6) are
essentially flat and elongate, and wherein the object or objects
(6) are wrapped with the longitudinal axis situated in parallel
with an axis extending between the first end and the second end (2,
4) of the film.
19. The system according to claim 11 wherein said objects (6) are
essentially flat and elongate, and wherein the object or objects
(6) are wrapped with the longitudinal axis situated in parallel
with an axis extending between the first end and the second end (2,
4) of the film.
Description
[0001] The invention relates to a method of wrapping one or more
objects in stretch film, said film comprising a tube-like section,
whose diameter is smaller than the diameter of the object or
objects to be wrapped, said film comprising a first end and a
second opposite and closed end, where the film is opened at its
first end and provided with a number of folds transversally of its
longitudinal axis, following which the film is expanded
diametrically before being brought to enclose the object or
objects. The invention also relates to a system of carrying out the
method, wherein one or more objects is/are wrapped in a tube-like
section of stretch film, said film comprising a tube-like section,
whose dimension is smaller than the dimension of the object or
objects to be wrapped, said film comprising a first end and a
second opposite and closed end; wherein the system comprises means
for opening the film at its first end and means for moving the film
across a hollow stretching unit and providing the film with a
number of folds transversally of its longitudinal axis, said
stretching unit comprising means for expanding the film
diametrically and means for forming holding-back means during
release of the film. Moreover, the invention relates to a use of
the method.
[0002] It is already known to wrap objects in stretch film. U.S.
Pat. No. 4,050,219, DE 2,706,955, DE 3101310 and EP 0 344 815 A1,
incorporated hereby by reference, teach processes, wherein a
tubular film having smaller circumferential dimension that the
object to be wrapped is shifted down over and arranged in folds on
a stretching unit, following which the end of the film is closed by
welding, whereby a bag is formed whose bottom faces upwards. The
film is subsequently expanded horizontally and pulled vertically
down over a number of items stacked on a pallet. In proximity of or
underneath the pallet the film is let go. By this wrapping the
items are stabilised on the pallet, the film remaining, following
application, to a certain extent tensioned, and likewise a certain
degree of coverage and protection are also imparted to the
items.
[0003] The thus known processes for wrapping are associated with
the exemplary weakness that the side facing towards the pallet
remains unprotected. It follows that the objects are not fully
wrapped and are therefore able to absorb moisture, smell and the
like. The objects being arranged on the pallet, which is in turn
sitting on a support, it is not possible to convey the film
underneath the pallet and close it off completely. It is a further
aspect that the processes are not suitable for objects that are not
arranged on a pallet or some other carrier means. The underside(s)
of the lowermost object(s) will thus be fully exposed. Moreover
there is a risk of the objects falling out of the wrapping from
below.
[0004] Novel aspects of the method according to the invention
comprise that the object or objects are supported and advanced
essentially horizontally or under a flat angle relative to the
horizontal into the expanded film from its first open end towards
the second end of the film, following which the film is pulled
around the object or objects, the folds of the film being unfolded
until the entire object or objects are introduced into the film,
following which the first end of the film is closed by joining for
complete enclosure of the object or objects in the film.
[0005] Hereby, compared to the prior art, it is accomplished that
the object or objects are enclosed to all sides and hence
completely. Thereby it is also accomplished that the objects need
not be arranged on a pallet or the like to avoid contact with a
support on which the wrapped object(s) is/are arranged.
[0006] According to a preferred embodiment the film may, during
advancement of the object or objects within the film, be arranged
at a space between a first and a second support, where the object
or objects is/are, during the advancement, moved from the first to
the second support. In this manner the object or objects may remain
essentially supported during the entire movement, including in
particular if the objects are long compared to the expanse of the
space.
[0007] According to an alternative embodiment the object or objects
can be arranged on the first support and seized with seizing means,
following which the object or objects are introduced into the film
and arranged on the second support, following which the object or
objects is/are let go.
[0008] According to yet an embodiment at least the first support
may comprise means for displacing the object or objects. This is
advantageous as the object or objects are to be moved from the
first to the second support. Thus, the means for displacement need
only eg push the object or objects.
[0009] According to a preferred embodiment the first support may be
displaceable or comprise a displaceable section, wherein the first
support or section is displaced and introduced into the expanded
film for further support of the object or objects during movement
from the first to the second support. Thereby the object or objects
can be supported during a larger part of the movement between the
first and the second support. That may be advantageous when
relatively short objects are wrapped.
[0010] According to yet a preferred embodiment the film may be
tensioned for tightening when being pulled around the object or
objects. Hereby less film is used and, likewise, the film becomes
tidy and smooth. When a number of objects are wrapped
simultaneously, the film will also support the objects. If the load
is increased and imparts a permanent increase in length to the
film, further film savings are obtained and the supporting effect
is enhanced. It is also obtained that objects having a tendency to
shrink will remain tightly wrapped and hence stable as the film
will follow the shrinkage due to its tensioning.
[0011] According to yet a preferred embodiment the first, the
second and the further support may be roller paths and/or conveyor
belts. This enables easy incorporation of the method in connection
with production plants where the objects are transported by those
types of transporter means.
[0012] Joining may advantageously be accomplished by welding which
yields a quick and reliable result.
[0013] According to yet an embodiment the object or objects may be
arranged on a carrier means such as a pallet. It may be practical
in case of stacked objects or objects that are otherwise difficult
to move.
[0014] The film may be dispensed from a storage unit from where it
is cut to a suitable length and closed at its other end by joining
prior to folding. Thereby the film may be eg in roller shape, which
saves place. Otherwise pieces of film manufactured in advance can
be used, that have already been shortened and closed at the one
end.
[0015] The film on the storage unit can be provided with
longitudinally extending folds that reduce the width of the film.
Thereby welding gussets used for joining the film need not be so
wide.
[0016] Novel aspects of the system according to the invention
comprise that the system comprises means for supporting and
advancing, essentially horizontally or at a flat angle in relation
to the horizontal, the object or objects through the stretching
unit with the film in expanded state for pulling of the film around
the object or objects and complete introduction of it or them into
the film and means for closing or joining the first end of the film
for complete enclosure of the object or objects in the film.
[0017] According to a preferred embodiment the system may comprise
a first roller path from where the object or objects is/are
advanced to the stretching unit, a displaceable roller path section
that can be displaced into the stretching unit when the latter has
expended the film and a second roller path for receiving the object
or objects. Thereby the system is readily integrated into
production plants where objects are transported in a similar
manner. By the displaceable roller path section the object or
objects are supported to a large extent.
[0018] According to a preferred embodiment the system may comprise
means for dispensing film from a storage unit.
[0019] According to a further preferred embodiment the system may
also comprise means for welding and means for cutting off the film,
which means are displaceable and arranged after the stretching
unit.
[0020] According to yet an embodiment the stretching unit may
comprise operated rollers for winding film, which rollers will,
during pulling of the film around the object or objects, form
holding-back means. Also the rollers may contain means measuring
the angulation, including encoders, whereby it is possible to
measure and control how much film is introduced onto the stretching
unit.
[0021] Novel aspects of the use of the method comprise that one or
more objects are wrapped, which objects are essentially flat and
elongate, and wherein the object or objects are wrapped with the
longitudinal axis situated in parallel with an axis extending
between the first and the second ends of the film,
[0022] In the following the invention will be described in further
detail with reference to figures that illustrate examples of
embodiments of the invention. The technique is given in a
simplified manner to emphasize the novel aspects of the invention.
Other structural details will be known to the person skilled in the
art and will appear ia from U.S. Pat. No. 4,050,219, DE 2706955, DE
3101310 and EP 344815 A1 incorporated herein by the present
reference.
[0023] FIGS. 1-5 show schematic cross-sections of a system
according to one embodiment of the invention. The figures teach ia
an example of a wrapping procedure;
[0024] FIGS. 6-7 teach schematic cross-sections of a system
according to an alternative embodiment of the invention.
[0025] FIGS. 1-7 show a number of objects 6 that are to be wrapped
in a tubular film 1. Also one single object 6 may be wrapped and,
likewise, two or more objects, including stacked objects and
objects arranged on a carrier means, may be wrapped. Preferably the
film 1 has an expanse which is smaller than the expanse of the
objects 6. The figures show a frame structure 26 that carries the
various components, including miscellaneous guide means, etc, that
partake albeit they are not shown; that may, however, readily be
exercised by the person skilled in the art as they present common
knowledge within the prior art wrapping techniques and appear from
the above-referenced respective documents.
[0026] FIG. 1 shows the film 1 that is dispensed from a storage
unit 8, from where it is conveyed to a distributor head 22 that is,
by means of a suction discs, able to open the film 1 at the first
end 2 thereof, when the latter is to be conveyed onto a stretching
unit 10. The distributor head 22 is movable and comprises means for
conveyance of the opened film 1 into or across the stretching unit
10. On the stretching unit 10 the film 1 is arranged in a number of
folds to occupy as much space as possible in the horizontal
direction. To assist movement of the film 1 the stretching unit may
comprise operated rollers 20, which rollers may also form
holding-back means when the film 1 is to be applied to the object
or objects 6 when the film 1 is pulled off the stretching unit
10.
[0027] In FIGS. 1-5 a first roller path 12 is shown that has a
displaceable roller path section 15, and a second roller path 14.
Roller paths are suitable for use in connection with the wrapping,
but conveyor belts are also suitable. The roller paths 12 and 14
can be completely or partially operated. If the roller path 12 is
not operated, the objects 6 can be pushed, eg by means of a
pneumatic cylinder to produce a desired movement. Moreover, FIGS.
1-5 also show means for welding 16 and means for cutting 18.
[0028] In FIG. 2 a suitable length of film 1 is arranged on the
stretching unit 10, and means for welding 16 join the film 1,
following which means for cutting 18 separate the piece of film on
the stretching unit 10 from the remainder of the film.
[0029] FIG. 3 shows that the distributor head 22 is displaced
upwards in order for it to be clear of the path of the objects 6
during the wrapping, but it may just as well be displaced sideways.
Means for welding 16 are also taken it clear positions. By joining,
see FIG. 2, the clear film on the stretching unit is provided with
a closed end 4, following which the film is expanded by the
stretching unit. During application of the film on the stretching
unit, it is pulled together, whereby the film is easily displaced
there across. By the expansion the circumferential dimension of the
film becomes diametrically larger than the objects 6. The
displaceable roller path section 15 is displaced into the
stretching unit 10 and into the expanded film. Between the roller
path 12 (and the section 15) and the roller path 14 a space 24 is
provided that allows the film to come from the underside of the
roller path section 15 and up on the top face of the roller path
14.
[0030] FIG. 4 shows how the film 1 is pulled off the stretching
unit 10 and pulled around the objects 6. The rollers 20 form
holding-back means whereby the film 1 is stretched suitably and
preferably tensioned to the effect that it is situated tightly
longitudinally of the objects. Holding-back means can be
accomplished in other ways without use of rollers, eg with a fixed
back edge that yields frictional resistance: The film 1 may also be
pulled with more tension, whereby a permanent increase in length is
imparted thereto. When the film 1 is pulled around the objects 6,
the film maintains a certain tensioning whereby the objects are
stabilised. A part of the tensioning compresses the stack of
objects 6 and thereby follows the objects should they settle during
transport or storage and, likewise, the pressure presses the
objects towards each other and hence creates mutual friction that
further contributes to stabilisation.
[0031] In FIG. 5 the objects 6 have been conveyed entirely into the
film, and the first end 2 has been closed by joining by means for
welding 16. This may be controlled in that--immediately preceding
release of the end 2 of the film from the rollers 20--means for
welding 16 are conveyed towards each other and join the film. If
necessary, excessive film 1 can be cut off. Prior to joining the
roller path section 15 can be withdrawn and the stretching unit be
pulled together, and likewise the film can be released from the
rollers 20 to thereby minimise the amount of excessive film
following the joining. It is noted that the same means for welding
16 can be used for joining both the first end 1 and the second end
4 of the film 1. The objects 6 are now completely wrapped. When the
objects 6 have been removed, the roller path section 15 can be
withdrawn, the stretching unit 10 pulled together, and the
distributor head 22 can be lowered down in front of the stretching
unit, whereby the system is back to its starting situation, see
FIG. 1, and renewed wrapping can be commenced.
[0032] FIG. 6 shows an alternative embodiment wherein a stretching
unit 10 is applied with film 1 corresponding to FIG. 1, but with
the difference that the stretching unit 10 can be moved vertically
and as shown receives the film 1 in a raised position. Hereby
improved space is accomplished around the stretching unit 10 for
miscellaneous functional means, whereby the film 1 is more readily
applied to the stretching unit. Thus, the distributor head 22 can
be stationary, while means 16 for welding the film 1 for forming a
closed end 4 are vertically movable, and including also adaptation
for closure of the open end 2 of the film following wrapping of an
object. FIG. 7 shows the stretching unit 10 in a lowered position,
which corresponds to the situation shown in FIG. 2. Now the film 1
must be expanded by the stretching unit 10, corresponding to FIG.
3, following which the wrapping can be implemented, see FIGS. 3, 4
and 5. In this context, too, the vertically movable means 16 for
welding are configured to close the end 2 of the film 1, whereby
complete wrapping is accomplished.
[0033] The figures show the use of roller paths, but movement of
the object or objects 6 can be accomplished in numerous ways. All
it takes are two supports (locations), between which the expanded
film 1 is arranged. Then the objects 6 can be moved, eg pushed by
means of piston, from the first to the second support, eg sliding
on the supports. Also the objects 6 can be seized with seizing
means, eg configured as a set tweezers or a claw or be taken by
means of forks like the forks of a forklift truck and conveyed from
one support to the other. The fundamental principle is that the
objects 6 are conveyed, while being supported, into the expanded
film 6, where the latter is pulled around the objects 6. Depending
on the length and rigidity (and nature in general) of the objects
6, the supports may be arranged with a given space there between
without tilting downwards. If that is a problem, a displaceable
support or part of the support, eg like a tongue, is conveyed to a
position to minimize said space.
[0034] Objects 6 may be of different lengths and yet be wrapped
with the same film and stretching unit 10. The length may be
controlled by measuring how much film 1 is arranged on the
stretching unit. It can be accomplished ia by providing the rollers
20 with encoders.
[0035] It will be understood that the invention as described in the
present description and figures can be modified or changed and
continue to be comprised by the scope of protection of the patent
claims that follow.
* * * * *