[0001] The invention relates to a tray-shaped packaging, in particular for food products,
the packaging having a bottom and a circumferential margin.
[0002] Such a packaging as well as a packaging machine and method for manufacturing same
are known, for example, from
DE 102010034021 A1 or the related document
US 2012/0036815 A1.
[0003] EP 0 535 451 A1 discloses a comparatively simple packaging in particular for food with a high grease
content, such as bacon strips. This packaging is produced by simply placing two transparent
foils on top of each other. In order to allow the bacon to become crispy during a
microwave treatment, the packaging comprises a pad underneath the food product, this
pad having hydrophobic and grease-absorbing properties. This pad can be produced in
a rather complicated manner, e.g. from blown microfibers (BMF).
[0005] It is the object of the present invention to provide a packaging that is easy to
manufacture, and which offers superior properties regarding a treatment of food products,
in particular greasy food products.
[0006] This object is solved by a tray-shaped packaging with the features of claim 1 as
well as by a deep drawing station according to claim 14 and by a deep drawing packaging
machine according to claim 15. Advantageous embodiments of the invention are referred
to by the dependent claims.
[0007] Due to having a tray-shaped configuration with a bottom and a circumferential margin,
the packaging according to the invention has a three-dimensional shape and is very
stable. The bottom of the packaging comprises at least one collecting section and
at least one support section. The support section comprises a plurality of elevations
for jointly supporting or carrying a product, in particular a food product. Supporting
the product on a plurality of elevations instead of supporting same with a planar
surface offers the advantage of establishing a drainage effect, which allows grease
dripping from the product during a heating of the product to be guided away from the
product. This allows the product (which might e.g. be bacon, ham or sausages) to become
crispier during the heating process.
[0008] Further, the packaging bottom comprises a collecting section. This collecting section
could synonymously be termed "reservoir section" and has the function of collecting
excess grease or other fluids, which drip from the product during a heat treatment.
In order to ensure that the grease or fluid is guided away from the product, the collecting
section, in total or at least in a certain area (i. e. at least in a sub-range of
its total area), has a greater depth relative to the margin of the packaging than
the support section. Typically, it may be advantageous to manufacture the collecting
section without any elevations in order to maximize the storage volume of the collecting
section.
[0009] Expediently, the support section is arranged between at least two collecting sections.
This allows excess grease to be guided away from the heated product even more efficiently.
[0010] In another embodiment, a support section may even be circumscribed entirely, i.e.
on all sides, from a collecting section.
[0011] Regarding the elevations, it turned out to be advantageous when these are pin-shaped,
pyramid-shaped, rib-shaped or dome-shaped. It is also conceivable to have elevations
of different size and/or different shape on a single packaging.
[0012] In principle, the elevations may be arranged in any configuration on the packaging,
which enables them to carry or support a product. Preferably, however, the elevations
are arranged in the form of a matrix having
n lines and
m columns, with
n and
m being integers and ≥ 1, respectively. Preferably,
n and
m are each > 3, such that there are at least 4 lines and at least 4 columns of elevations.
This will ensure a generally homogeneous distribution of the weight of the product,
thereby preventing an undesirable deformation of the product.
[0013] Expediently, each of the elevations comprises a peak, and the peaks of all elevations
of a common support section are arranged in a common plane. Depending on the product
and on the optimum way to present the product within the packaging, the common plane
may be planar or curved.
[0014] In an advantageous embodiment of the invention, drainage channels leading towards
a single collecting section or towards one (or several) of the plurality of collecting
sections are arranged between the elevations. This will ensure an even faster and
more efficient guiding of the excess grease away from the product.
[0015] This efficiency may be increased even further by providing the drainage channels
with a downward slope directed towards the collecting section.
[0016] Alternatively, or additionally, it is conceivable that the support section of the
bottom is convex on its side facing the interior of the packaging. The convex shape
refers to the (virtual) surface combining the valleys between the elevations. The
convex shape of the surface will again lead to an efficient drainage of the excess
grease towards the collecting section.
[0017] In order to be able to cook or grill the products while remaining within the packaging,
it is advantageous if the packaging is heat resistant up to a temperature of 150°
C, preferably up to a temperature of at least 200° C. When contemplating a use of
the packaging in a microwave oven, it is further advantageous if the packaging is
essentially transparent to microwave radiation.
[0018] An example of a material that may be used for the bottom and the margin of the packaging
is a polyethylene (PET) web or foil. This packaging material may both offer the desired
heat resistance, and an advantageous transparency.
[0019] Even more preferred is the use of a bi-axially oriented polyethylene (PET) foil (boPET
foil) for at least the bottom and the margin of the packaging. Such a boPET foil,
which is obtainable, e.g. under the trade name Mylar, is very heat resistant and is
also stable at temperatures below the freezing point, such that the goods packaged
with this material can also be frozen. Further, this material is transparent and has
a high resistance against punching and stretching.
[0020] The invention is also directed to a deep drawing station for producing a tray-shaped
packaging of the above-described type from a web-like material, such as boPET, this
deep drawing station preferably comprising a heating device, for example an electrical
heating device, as well as a forming or deep drawing tool.
[0021] Further, the invention also relates to a deep drawing packaging machine that is configured
for manufacturing a tray-shaped packaging of the above-described type.
[0022] In the following, advantageous embodiments of the invention are described with reference
to the accompanying drawings, in which the individual figures show:
- Figure 1
- a perspective view of a thermoforming packaging machine,
- Figure 2
- a perspective view of a first embodiment of a packaging according to the invention,
- Figure 3
- a top view of the packaging of figure 2,
- Figure 4
- a lateral view of the packaging of figure 2,
- Figure 5
- a perspective view of a second embodiment of a packaging according to the present
invention,
- Figure 6
- a top view of the packaging of figure 5,
- Figure 7
- a lateral view of the packaging of figure 5,
- Figure 8
- a sectional view of a third embodiment of a packaging according to the present invention,
and
- Figures 9a to 9d
- different embodiments of the elevations used in the packaging according to the present
invention.
[0023] Identical components are designated by identical reference numerals throughout the
figures.
[0024] Fig. 1 shows, in a perspective view, a thermoform packaging machine 1 comprising
a forming station 2, a sealing station 3, a cross cutting station 4 and a longitudinal
cutting station 5, which are arranged on a machine frame 6 in a working direction
R in this sequence. On the input side, a supply roll 7 is provided on the machine
frame 6, from which a first web-shaped material 8, e.g. a boPET foil, is unwound.
In the area of the sealing station 3, a material storage unit 9 is provided, from
which a second web material 10, e.g. a cover film such as a PET foil, is unwound.
On the output side, a discharge device 13 in the form of a transport conveyor is provided
at the thermoform packaging machine 1, with which finished, singulated packages 21
are transported away. Furthermore, the packaging machine 1 comprises a feeding device,
which is not shown, said feeding device gripping the first web-shaped material 8 and
transporting it cyclically in a main work cycle in the working direction R. The feeding
device can, for example, be realized by laterally arranged transport chains.
[0025] In the embodiment shown, the forming station 2 (or deep-drawing station) is realized
as a thermoforming station in which package lower parts or tray-shaped packagings
14 are formed in the first web-shaped material 8 by thermoforming (or deep-drawing).
The forming station 2 comprises a heating element 2a and a forming tool 2b and can
be configured such that in the direction perpendicular to the working direction R
several tray-shaped packagings 14 are formed side by side. In the working direction
R behind the forming station 2, an infeed line 15 is provided, in which the package
lower parts 14 formed in the first web-shaped material 8 are filled with the product
16.
[0026] The sealing station 3 is provided with a closable chamber 17 in which the atmosphere
in the tray-shaped packagings 14 can be substituted, prior to sealing, by an exchange
gas or by an exchange gas mixture, e.g. by gas flushing.
[0027] The cross cutting unit 4 is configured as a punch separating the first web-shaped
material 8 and the second web material 10 in a direction transversely to the working
direction R between neighbouring package lower parts 14. In so doing, the cross cutting
unit 4 works such that the first web-shaped material 8 is not cut across the whole
width of the web, but remains uncut in at least an edge area thereof. This allows
controlled further transport by the feeding device.
[0028] In the embodiment shown, the longitudinal cutting unit 5 is configured as a blade
arrangement by means of which the first web-shaped material 8 and the second web material
10 are cut between neighbouring tray-shaped packagings 14 and at the lateral edge
of the first web-shaped material 8, so that, downstream of the longitudinal cutting
unit 5, singulated packages 21 are obtained.
[0029] The packaging machine 1 is additionally provided with a controller 18. This controller
18 is used for controlling and monitoring the processes taking place in the packaging
machine 1. A display device 19 with operating controls 20 serves to make the sequences
of process steps in the packaging machine 1 visible to an operator and to influence
them by the operator.
[0030] Figure 2 shows a perspective view of a tray-shaped packaging 14 of the present invention.
The packaging 14 comprises a generally horizontal bottom 21, a circumferential and
again substantially horizontal margin 22, as well as side walls 23, circumscribing
the bottom 22 and interconnecting the bottom 21 with the margin 22. The bottom 21,
margin 22 and side walls 23 of the packaging 14 are deep drawn from a web material,
such as PET, boPET or a multilayer web material. For example, any material disclosed
in
US 7,705,078 B2 can be used, this document being hereby incorporated by reference with respect to
the material.
[0031] The bottom 21 of the packaging 14 comprises a central support section 24, as well
as two lateral collecting or reservoir sections 25, i.e. one to either side of the
support section 24. A step 26 is present between the support section and each of the
collecting sections 25, such that each of the collecting sections 25 has a greater
depth relative to the margin 22 than the support section 24.
[0032] Further, a plurality of pin-shaped elevations 27 is arranged on the support section
24. In the present embodiment, the elevations are arranged in a matrix of
n=
11 lines and
m=
12 columns. The elevations 27 have a height of e.g. 1-3 mm above the remainder of the
support section 24. They serve to support the underside of a product, in particular,
a food product, such as bacon, ham or sausages placed on the support section 24.
[0033] Figure 3 shows a top view of the tray-shaped packaging 14 of figure 2. Figure 4 shows
a lateral view of the packaging 14. From figure 4, it might be appreciated that the
step 26 provides a smooth transition from the support section 24 towards the collecting
sections 25, respectively. It might further be appreciated that the elevations 27
have a height that is low enough in order to allow sufficient space for the product
between the peak of the elevations and a cover foil 28 sealed to the margin 22 with
a circumferential seal, the cover foil 28 extending in the same plane as the margin
22.
[0034] Figure 5 shows a second embodiment of a packaging 14 of the present invention. This
second embodiment of a tray-shaped packaging 14 is consistent with the first embodiment
in comprising a central support section 24 and two lateral collection sections 25,
as well as a margin 22 and side walls 23 circumscribing the bottom 21.
[0035] In contrast to the first embodiment, however, the elevations 27 are now pyramid-shaped.
The pyramidal elevations 27 are arranged in a matrix pattern. Again, a step 26 is
present between the central support section 24 and each of the collecting sections
25, such that each collecting section 25 entirely has a larger depth relative to the
margin 22 than the support section 24.
[0036] Figure 6 shows a top view of the tray-shaped packaging 14 of figure 5. Figure 7 shows
a lateral view of the packaging 14 of figure 5. Figure 7 allows appreciating in particular
the pyramid shape of the elevations 27.
[0037] In each of the embodiments of the packaging 14 according to figure 2 or 5, drainage
channels 29 are provided between the elevations 27 (cf. figures 3 and 6). These drainage
channels 29 are configured to lead excess grease or liquid dripping from the product
towards one of the collecting sections 25.
[0038] Further, figures 4 and 7 show that the tray-shaped packaging 14 may rest stably on
the two collecting sections 25 when it is placed on a horizontal surface, such as
an oven tray. Due to the step 26, the central support section 24 is then elevated
with respect to the surface on which the packaging 14 is placed, such that hot air
can flow around the complete packaging 14, in particular below the support section
24. This accelerates the heating of the product within the packaging 14.
[0039] Figure 8 shows a third embodiment of a tray-shaped packaging 14 according to the
present invention. This embodiment is similar to the embodiment shown in figure 5,
except for lacking a step between the central support section 24 and the two lateral
collection sections 25. Rather, the bottom of the support section 24 has a convex
shape on its side facing the interior of the packaging 14. The elevations 27 on the
support section 24 are again pyramid-shaped. However, the size of the elevations 27
is smaller in the center and larger in the periphery of the support section 24. This
ensures that the peaks 30 of all elevations 27 are arranged in a common plane (P),
which is represented by a dashed line. In the present embodiment, this plane is planar,
but it could alternatively be curved.
[0040] Figure 8 shows that the packaging 14 rests on a support surface 31, such as an oven
tray.
[0041] Figures 9a to 9d show different embodiments of the elevations 27, which can be provided
on the support section 24. In figure 9a, the elevation 27 is pin-shaped. Its top surface
constitutes the peak 30 of the elevation 27, i.e. the pin-shaped elevation 27 has
a planar, two-dimentional peak 30.
[0042] Figure 9b shows the pyramid-shaped elevation 27 used in the embodiment of figure
5. Here, the peak 30 corresponds to the peak of the pyramid.
[0043] Figure 9c shows a dome-shaped elevation 27, which may have a circular or ellipsoidal
cross-section.
[0044] Figure 9d shows a rib-shaped elevation 27. In this embodiment, the elevation 27 has
a linear peak 30, corresponding to the top edge of the rib.
[0045] The packaging 14 of the present invention is advantageous in particular for greasy
food products, such as bacon, ham and sausages. When being placed in an oven or a
microwave oven and heated, the excess grease may drip from the product and enter into
the drainage channels 29 between the elevations 27. From here, the grease may flow
into the collecting sections 25, thereby allowing the food product to be crispier
after heating.
[0046] Starting from the described embodiments, the invention may be carried out in various
alternative ways. For example, any shape, size and arrangement of the elevations 27
are conceivable. In particular, the shape of the elevations 27 is not limited to the
embodiments shown in 9a to 9d. For example, elevations 27 may also have a conical
shape.
1. Tray-shaped packaging (14) for a product, comprising a bottom (21) and a circumferential
margin (22), wherein the bottom (21) comprises at least one collecting section (25)
and at least one support section (24), wherein the support section (24) comprises
a plurality of elevations (27) for supporting the product, and wherein the collecting
section (25) at least in certain areas has a greater depth relative to the margin
(22) of the packaging (14) than the support section (24).
2. Tray-shaped packaging according to claim 1, wherein the support section (24) is arranged
between at least two collecting sections (25).
3. Tray-shaped packaging according to claim 1, wherein the support section (24) is circumscribed
entirely by a collecting section (25).
4. Tray-shaped packaging according to one of the preceding claims, wherein the elevations
(27) are pin-shaped, pyramid-shaped, rib-shaped or dome-shaped.
5. Tray-shaped packaging according to any of the preceding claims, wherein the elevations
(27) are arranged in the form of a matrix with n lines and m columns, wherein n and m are integers and each larger than 1, preferably n and m ≥ 4, respectively.
6. Tray-shaped packaging according to any of the preceding claims, wherein each elevation
(27) comprises a peak (30) and wherein the peaks (30) of all elevations of each support
section (24) are arranged in a common plane (P).
7. Tray-shaped packaging according to any of the preceding claims, wherein drainage channels
(29) leading towards the at least one collecting section (25) are provided between
the elevations (27).
8. Tray-shaped packaging according to claim 7, wherein the drainage channels (29) have
a downward slope towards the collecting section (25).
9. Tray-shaped packaging according to one of the preceding claims, wherein the support
section (24) of the bottom (21) is convex on its side facing the interior of the packaging
(14).
10. Tray-shaped packaging according to any of the preceding claims, wherein a step (26)
is arranged between the support section (24) and the collecting section (25).
11. Tray-shaped packaging according to any of the preceding claims, wherein the packaging
(14) is heat resistant up to a temperature of at least 150° C, preferably up to a
temperature of at least 200° C.
12. Tray-shaped packaging according to any of the preceding claims, characterized in that the bottom (21) and the margin (22) of the packaging are made from a PET foil.
13. Tray-shaped packaging according to any of the preceding claims, wherein the bottom
(21) and the margin (22) of the packaging (14) are made from a bi-axially oriented
PET foil.
14. Deep drawing station (2) for producing a tray-shaped packaging (14) according to any
of the preceding claims, comprising a forming tool (2b) adapted for deep drawing a
tray-shaped packaging (14) with a bottom and a circumferential margin (22), such that
the bottom (21) comprises at least one collecting section (25) and at least one support
section (24), wherein the support section comprises a plurality of elevations (27)
for supporting a product and wherein the collecting section (25) at least partially
has a greater depth relative to the margin (22) of the packaging (14) than the support
section (24).
15. Deep drawing packaging machine (1) for manufacturing a tray-shaped packaging (14)
according to any of claims 1 to 13.