[0001] The present invention relates to a transport unit according the preamble of claim
1 and 4 and a method of manipulating the wrapping foil.
[0002] From EP 0 946 394 B1, a transport unit is known, where a plurality of insulating
panels are stacked in two or more stacks adjacent each other on mutually spaced support
elements of a material suitable for use for insulation purposes. The support elements
may have different orientations relative to the position of the stacks. The stacks
of panels and the support elements are enclosed in a protective foil wrapping. This
wrapping also provides for a stable transport unit. This transport unit is composed
of insulating panels, e.g. 1000x600 mm or 2000x600 mm, length and width respectively,
and it is lifted by normal lifting means, such as a lift fork. At the user's end,
the panels may be cut into size before it is fitted into the building construction,
e.g. a roof construction.
[0003] The fibrous material may alternatively be provided in rolls instead of stacked panels.
Such rolls of insulation material are also wrapped with a wrapping foil in order to
prevent the roll from unwinding and to protect the insulation material during transport.
[0004] With a protective wrapping foil surrounding most of the entire transport unit, there
may be a risk of water penetrating through the uncovered foil free areas and becoming
trapped in the bottom of the unit, e.g. the support element. Since the transport units
often are free exposed and thereby subjected to rain, the penetration of water is
always latent. Some regions of the transport unit may accumulate water, and this is
a particular problem when for instance support elements of fibrous material useable
for insulation purposes are used. These support elements are useless if they are soaked
in water. Since in some circumstances the support elements are sold together with
the rest of the transport unit, it is imperative to maintain the support elements
dry to keep customers satisfied and to avoid the need for costly disposal of useless
support elements of soaked fibrous material.
[0005] In this light, it is an object of the invention to provide a reliable solution to
preventing the assembly of water in the support elements. Moreover, it is an object
to provide a drainage, which does not critically reduce the strength of the wrapping
foil and jeopardises the quality of the material in the transport unit.
[0006] These objects are obtained by a transport unit according to the invention.
[0007] The invention relates to a transport unit comprising a plurality of panels, said
panels being stacked on support means, wherein the panels and the support means may
be retained together by a wrapping foil surrounding them, or the transport unit comprising
at least one roll of fibrous web material, in particular material for insulation purposes,
wherein said roll may be stacked on support means, and wherein the at least one roll
is retained together by a wrapping foil surrounding at least the fibrous material.
It is irrelevant for the purpose of the invention how the foil is wrapped around the
transport unit. The foil may be used as a single sheet enveloping the panels and the
support means, but may also be used as sheets enveloping the support means and the
panels or stacks of panels separately.
[0008] The invention consists of a transport unit of the above-mentioned kind, wherein at
least one drain aperture is provided in the lower portion of the wrapping foil or
the portion in contact with the support means, or the portion where water accumulation
is most likely to occur, and that the at least one aperture is provided by a treatment
in the wrapping foil so that the aperture is reinforced along the rim of the apertures
and if there is an overlap of layers of wrapping foil these are joined together along
the rim or part of the rim of the apertures. The treatment could be heat treatment,
mechanical treatment or a chemical treatment, e.g. by use of an acid solution, or
a combination of one or more of these treatments in order to achieve the same result.
[0009] Hereby, a drain aperture is provided by "burning" or "etching" a relatively small
hole in the plastic wrapping foil. By "burning" or etching the apertures through the
layers of foil, the overlapping layers of foil may be joined together by being melted
together along the rim or part of the rim. This means that the holes in the individual
layers of foil cannot be displaced relative to each other, which in turn means that
the drain openings are not subsequently closed and the drainage function jeopardised.
By melting the apertures in the wrapping foil, a reinforced edge along the aperture
or part of the aperture may be provided, which compensates for the tensile weakness,
which would otherwise be occurring by providing a hole in the wrapping foil.
[0010] In a first embodiment of the invention, the panels are panels of fibrous insulating
material, preferably stacked in at least one stack on support means consisting of
mutually spaced support elements consisting of fibrous material suitable to be used
for insulation purposes.
[0011] In a second embodiment, a roll of fibrous material is provided in the transport unit
and the at least one roll is provided on support means consisting of mutually spaced
support elements consisting of fibrous material suitable to be used for insulation
purposes.
[0012] Preferably, the at least one aperture is provided in the portion of the wrapping
foil covering the support elements. In the preferred embodiment, at least two apertures
are provided in connection with each of the support elements. As mentioned above,
the aperture(s) independently of how the foil is used, shall be provided in the region
or regions where water accumulation (water ponding) is most likely to occur. Often
this occurs in the region near the support elements or in the lower region of the
stack of panels, which faces the support elements.
[0013] The invention also relates to a method of making an aperture in a wrapping foil,
preferably a polymeric foil, which is surrounding a stack of panels on support means
in a transport unit by advancing a heated member into engagement with the wrapping
foil and melting an aperture having a geometry corresponding to the shape of the engagement
end of the tuberous member.
[0014] Alternatively, drainage may be accomplished by providing a cut or similar mechanical
treatment in the foil, whereby the at least one aperture has a geometry corresponding
substantially to the shape of the engagement end of the cutting means.
[0015] Drainage may also be accomplished by means of a chemical treatment in the foil, whereby
the at least one aperture may acquire a random geometry but is big enough to allow
for the evacuation of accumulated water.
[0016] The aperture provided by a heated member may be a generally round hole. In the method
of providing this aperture, the heated member is preferably a tubular member with
a generally circular or oval cross-section. The aperture could also be provided by
a laser. Preferably, the at least one aperture is circular, preferably with a diameter
between 0.5 to 50 mm, more preferably between 5 and 30 mm and most preferably between
15 and 25 mm. A large number of very small holes could be an alternative way of obtaining
an equivalent result. Since the wrapping foil is usually wound around the fibrous
material with an overlap and/or with a multiple of layers, by providing a substantially
circular hole, the concentration of tensile stress around the hole it is kept low
thus reducing the risk of damaging the wrapping foil.
[0017] In a preferred embodiment of the invention, the at least one aperture is a semi-annular
opening leaving an uppermost connecting portion, so that a flap is provided which
is connected to the wrapping foil. The semi-annular opening is preferably semi-circular,
elliptical, or similar smooth partially annular shape. The opening preferably circumscribes
25-98% and more preferably 50-90% of a full circle. This type of aperture may be provided
by a method wherein the heated member is provided with an end section engaging the
wrapping foil, which has a generally U-shaped or semi-circular shape. By providing
a semi-circular or equivalently shaped flap, i.e. by only melting away 50%-90%, e.g.
80%, of the full circle, no waste material is produced, which otherwise must be removed
from the production site.
[0018] In the preferred embodiment, the wrapping foil is multi-layered. According to the
method, the heated member joins together a multiple of layers of polymeric wrapping
foil along the rim of the apertures in a plastic welding process. The apertures are
provided by a heat welding treatment in a polymeric wrapping foil and that the layers
of wrapping foil are joined together along the rim of the apertures. The equipment
for carrying out the method may be a portable equipment with an extendable heating
member or equipment installed in the production line subsequent to the packaging line
where the transport units are built and wrapped with the foil.
[0019] In the following, the invention is illustrated with reference to some most preferred
embodiments shown in the accompanying drawings, in which:
- Fig. 1
- is a front view of a transport unit according to a first preferred embodiment of the
invention;
- Fig. 2
- is a side view of a transport unit according to the invention;
- Figs. 3 and 4
- are detailed views of two embodiments of the invention;
- Figs. 5 and 6
- are principal side views of the method of making apertures in the wrapping foil; and
- Fig. 7
- is a front view of a transport unit according to second preferred embodiment of the
invention.
[0020] In figure 1 a transport unit comprising one or more stacks of panels 1, in particular
panels of insulation material is shown. The stack of panels 1 is supported on support
elements 3 and wrapped in a protective wrapping foil 2, which also constitutes the
retention means for retaining the panels 1 in their stacked position during transport.
[0021] The stack of panels 1 is placed on support elements 3 constituting the bottom side
of the transport unit. The transport unit further has a top surface, a front and rear
surfaces and two surfaces. The foil 2 is typically wrapped around the top and bottom
and the side surfaces as shown in fig. 1. The wrapping foil 2 also provides the retention
of the stack during transport besides protecting the fibrous insulation panels 1.
The panels may be rectangular panels or wedge-shaped panels. As mentioned above, the
fibrous material may alternatively be provided in rolls.
[0022] The support elements 3 are preferably made of fibrous material, which is suitable
for insulation purposes. The wrapping foil 2 encompasses both the panels 1 and the
support elements 3. In the section of the wrapping foil covering the support elements
3, which in the embodiment in fig. 1 includes the region of potential water accumulation,
apertures 4 are provided in the vicinity of each of the exterior comers of the support
elements 3, for instance as shown in fig. 1.
[0023] In fig. 4, the transport unit is shown in a side view. As indicated in this figure,
the apertures 4 are positioned adjacent the exterior longitudinal sides of the support
elements.
[0024] The apertures 4 may be circular as shown in fig. 2 or semi-circular as shown in fig.
3. In order to prevent water from accumulating in the support elements in the bottom
of the transport unit, an aperture having a free opening is not necessary. It can
be sufficient to have a slit, as it is the case with the embodiment having semi-circular
apertures 4, see fig. 3. The advantage of the aperture being a partially annular slit
is that there are no blanks which are cut away from the holes and which must be removed.
This makes the production of the apertures 4 easier as the need for tidying the production
floor is reduced compared to making "full" holes.
[0025] As shown in figs. 5 and 6, the apertures 4 are produced by advancing a member 5,
preferably a heated member, having at least a preferably heatable end section 6 towards
the wrapping foil 2 at the position for the apertures 4. The heated member 5 is advanced
forward to engage the wrapping foil 2, which is supported by the support element 3
immediately behind the foil 2. As the end section 6 of the heated member 5 is fully
engaged with wrapping foil, the aperture is melted through the foil or foils 2. Since
the fibrous insulation material behind the foil is fire resistant, there is no danger
of damaging the fibrous panels in the transport unit during the aperture-making process.
[0026] In fig. 7 is shown another embodiment of the invention, where the water accumulation
region is at the bottom region of the stack of panels 1. In this embodiment, the stack
of panels 1 is partially wrapped in a foil 2 and the support means 3 are separately
wrapped in an additional foil 2'. The support means 3 are at the upper surfaces of
the support wrapping foils 2' adhesively attached to the wrapping foil 2. The apertures
4 are provided in the lowermost region of the "panel stack" portion of the transport
unit, as this is the most likely region for water accumulation.
[0027] By the invention, it is realised that the apertures may have different shapes. Accordingly,
by the term circular is meant any annularly shape having a continuous curvature. Accordingly,
elliptical, oval or other equivalent shapes are considered to be comprised in the
term circular, as well as multi-edged holes which in practise have the same function.
Furthermore, forces in the single or multiple layer foil may stretch it and thereby
change the initial shape of any aperture.
1. A transport unit comprising a plurality of panels and/or rolls, said panels and/or
rolls being stacked on support means, wherein the panels and the support means are
retained by wrapping foil,
characterised in that
at least one drain aperture is provided in the portion of the wrapping foil, where
water accumulation is most likely to occur, and that the at least one aperture is
provided by a treatment in the wrapping foil.
2. A transport unit according to claim 1, wherein the panels and/or rolls are of fibrous
insulating material.
3. A transport unit according to claim 2, wherein the panels are stacked in at least
one stack on support means consisting of mutually spaced support elements consisting
of fibrous material suitable to be used for insulation purposes.
4. A transport unit according to claim 3, wherein the at least one aperture is provided
in the portion of the wrapping foil covering the support elements.
5. A transport unit according to claim 3 or 4, wherein at least two apertures are provided
in connection with each of the support elements.
6. A transport unit according to claim 3, wherein the at least one aperture is provided
in the portion of the wrapping foil covering the lowermost section of the stack of
panels and/or rolls above the support elements.
7. A transport unit according to claim 3 or 6, wherein at least two apertures are provided
on at least two sides of the transport unit.
8. A transport unit according to any of the preceding claims, wherein the at least one
aperture is a generally round hole.
9. A transport unit according to any of the preceding claims, wherein the at least one
aperture is circular, preferably with a diameter of 0.5 to 50 mm, more preferably
5 to 30 mm, and most preferably 15 to 25 mm.
10. A transport unit according to any of the claims 1 to 8, wherein the at least one aperture
is a semi-annular opening leaving an uppermost connecting portion, so that a flap
is provided which is connected to the wrapping foil.
11. A transport unit according to claim 10, wherein the semi-annular opening is semi-circular,
preferably circumscribing 50-90% of a full circle.
12. A transport unit according to any of the preceding claims, wherein the wrapping foil
is multi-layered.
13. A transport unit according to any of the preceding claims, wherein the wrapping foil
is single-layered.
14. A transport unit according to any of the preceding claims, wherein the at least one
aperture is reinforced along the rim of the aperture.
15. A transport unit according to any of the preceding claims, wherein the at least one
aperture is provided in the wrapping foil comprising an overlap or multiple of layers
of wrapping foil at the position of the aperture, by said layers being joined together
along the rim of the aperture.
16. A transport unit according to claim 15, wherein the overlap or multiple of layers
of wrapping foil at the position of the aperture is provided by a heat member.
17. A transport unit according to claim 15, wherein the heat member is substantially tubular.
18. A transport unit according to claim 1, wherein the panels and the support means are
retained together by a common wrapping foil.
19. A transport unit according to claim 18, wherein the transport unit is provided with
additional support elements placed in between the stack of panels and the support
means.
20. A transport unit according to claim 19, wherein the additional support elements are
made of a material selected from a group comprising wood, plastic or the like.
21. A method of making an aperture in a wrapping foil, which is surrounding a stack of
panels on support means in a transport unit by advancing a member into engagement
with the wrapping foil and providing an aperture having a geometry corresponding to
the shape of the engagement end of the tuberous member.
22. A method according to claim 21, whereby the member is a heated tubular member with
a generally circular cross-section.
23. A method according to claim 21, whereby the member is provided with an end section
engaging the wrapping foil, which has a generally U-shaped or semi-circular shape.
24. A method according to any of the claims 21 to 23, whereby the member joins together
a multiple of layers of polymeric wrapping foil along the rim of the apertures in
a plastic welding process.
25. A method according to any of the claims 21 to 24, whereby the member, which is advanced
towards the wrapping foil, is a heated member and the aperture is melted in the wrapping
foil.
26. A method according to any of the claims 21 to 25, whereby the member, which is advanced
towards the wrapping foil, applies a chemical means, such as an acid or an basic solution,
for forming one or more apertures in the wrapping foil.