[0001] The invention relates to a compression plate, which ensures a tight wrapping of one
or more compressible objects.
Background
[0002] In the industry of insulation materials it is of outmost importance that the cubic
content of the packets of insulation material is reduced to a minimum, enabling transportation
of an increased number of packets per volume. Further, in order to simplify both the
transportation of insulation material and to enhance the operability of the packages
of insulation material on site, it is desired to bundle multiple packages of insulation
material.
[0003] In general, compressible objects such as insulation materials are only compressible
in one direction. Compression in any other direction than this will damage the properties
of the insulation material. This unidirectional compression characteristic results
in a number of problems described in the following.
[0004] Horizontal compression could also be performed. Here e.g. three packages of pre-compressed
objects are led horizontally into a vertically oriented foil and are horizontally
over-compressed. At this point three surfaces (top, bottom and one end) are covered
in foil, the last and fourth surface is not yet covered. In order to maintain that
over-compression before the foil is closed, spears are directed at the back of the
last of the three packages - just in front of the fourth surface. The foil is hereafter
closed and the spears withdrawn. Consequently, some of the potential energy of the
over-compressed objects is released, whereby the objects expand and the foil is tightened.
The over-compression causing the expansion of the objects is, however, undesired,
as this can potentially destroy intended function of the objects. In the case of insulation
material this could then lead to a reduction of the insulation properties. A solution
to this could be to reduce the over-compression to a minimum. However, in the present
example of three compressible objects that are bundled and packed in one, there is
a risk that the centre object will fall out of the package. This is because most of
the potential energy of the compressed objects will be released during expansion.
The remaining potential energy is not sufficiently high to keep the centre object
in place, which then risk falling out of the final package.
[0005] In the case of vertical compression, e.g. three packages - comprising a plurality
of stacked objects - are led horizontally into a vertically oriented foil. Due to
the unidirectional compressibility of the objects, they are only led into the foil
without any horizontal compression. When three sides of the three packages have been
covered in foil, spears are directed in front of the fourth side. Hereafter the objects
are compressed, the foil is closed at the fourth side, and the spears are closed.
Since the objects are directed into the foil in an uncompressed state, the length
of the foil will be larger than the circumference of the compressed objects. Withdrawing
the spears and removing the compression will therefore release the potential energy
of the objects, which will expand. However, as there is more space left in the end
of the package because of the withdrawn spears (fourth side), this expansion will
be uneven. Hence, the final package that was to be rectangular will instead have an
irregular shape, by e.g. having a larger height in one end, compared to the other.
Description of the invention
[0006] The present invention relates to a packaging machine for packaging at least one compressible
object into foil comprising at least one compression plate, where the at least one
compression plate comprises at least two segments which can be sloped individually,
whereby it is obtained that the at least one compressible object can be unevenly compressed
by the compression plate during the packaging process of the at least one compressible
object. This is advantageous as the uneven compression of the compressible objects
enables a desired uneven expansion of the compressible objects, when the compression
plate no longer exerts its compression. Hereby an even final package is obtained.
If the packaging machine employs spears as described above, the compression plate
can advantageously compress the compressible objects more in the end of the spears.
This because the foil wrapped along and around this end of the compressible objects
and the spears lengthwise will correspond to the foil wrapped around the objects in
the opposite and less compressed end. A further advantage is that the compression
plate only compresses the compressible objects in the direction where the compressible
objects are compressible. Damage to the properties of the compressible objects is
thereby avoided.
[0007] In another embodiment of the packaging machine the at least two plate segments are
interconnected by at least one hinge. In a further embodiment the compression plate
further comprises at least one hinge connected to one of the at least two plate segments.
Apart from the advantages already mentioned, this embodiment is advantageous as e.g.
the number, form and size of the plate segment and hinges can be varied for example
to accommodate a desired product type or product range.
[0008] In yet another embodiment of the packaging machine the compression plate comprises
a flexible plate and at least one eyelet mounted on the flexible plate for separating
at least two segments of said flexible plate. This embodiment is advantageous as the
bending of the flexible plate can constitute a more coherent surface.
[0009] In other embodiments of the packaging machine, the compression plate compresses the
at least one compressible object by pneumatic means or hydraulic means. In a further
embodiment of the packaging machine the compression is employed by means of linear
actuators. These different means are advantageous as they can be used to serve different
purposes depending on e.g. the properties of the compressible objects and/or existing
manufacturing equipment.
[0010] The present invention further relates to a method for wrapping a foil onto at least
one compressible object, comprising the steps of wrapping at least one side of the
at least one compressible object whereby the foil covers the at least one side and
compressing the at least one compressible object unevenly. In a further embodiment
the method comprises the step of closing the foil after the at least one compressible
object has been unevenly compressed. Here the advantages are as described above.
Brief description of the drawings
[0011]
Figure 1 illustrates a packaging machine according to the present invention for packaging
compressible objects, where the machine comprises a compression plate.
Figure 2 illustrates the packaging machine of figure 2 seen in a close up side view.
Figure 3a-d illustrate the steps by which the compression plate is utilized in the
packaging process.
Figure 4 illustrates an alternative embodiment of the compression plate.
Figure 5 illustrates an alternative embodiment of the compression plate.
Description of embodiments
[0012] Figure 1 illustrates a packaging machine 100 according to the present invention for
packaging compressible objects 101, where the packing machine 100 comprises a first
103 and a second transportation table 105, a fence 107 and a pushing device 109. The
packed compressible objects 101 are only unidirectional compressible. The objects
101 can be directed into the packaging machine 100 side by side, in stacks, or as
a plurality of stacks lying side by side or end to end. The stacks can be pre-packed
in a compressed as well as in an uncompressed state. The present packaging machine
100 is embodied such that the compressible objects 101 can be compressed vertically.
[0013] The packaging machine 100 also comprises a first roll of foil 111 situated below
the first transportation table 103 and a second roll of foil 113 placed above the
first transportation table 103. The arrows seen on the two rolls of foil indicate
the direction of movement of the foil. Tightening devices (not shown) ensure that
the two rolls of foil 111, 113 are kept stretched for tight wrapping of the compressible
object(s).
[0014] The packaging machine 100 additionally comprises two sets of spears; a first set
comprising upper 115 and lower spears 116 and a second set likewise comprising upper
117 and lower spears 118.
[0015] The packing machine 100 further comprises a compression plate 119, where the compression
area of the compression plate 119 substantially corresponds to the area of the compression
surface of the objects facing the compression plate 119. The compression plate 119
is employed so as to vertically compress the compressible objects 101. The compression
plate 119 comprises a first 121 and a second segment 123 connected by a hinge 125,
which is placed perpendicularly to the conveying direction of the two transportation
tables 103, 105. This means that the two segments 121, 123 of the compression plate
119 can be sloped individually. The compression plate can be embodied in a number
of ways, e.g. by varying the number of segments and hinges.
[0016] The packaging machine 100 additionally comprises a first 127 and a second welding
bar 129, which are placed such that when pushed together, the wrapping foil 111, 113
is situated in between the two. Hence, when not in use, the welding bars 127, 129
are placed on each side of the foil 111, 113. The two welding bars 127, 129 can be
brought together by moving either both of the welding bars vertically or by moving
only one of the welding bars 127, 129.
[0017] Figure 2 illustrates a side view of the packaging machine of figure 1. The compressible
objects 101 are partly situated on the first 103 and partly on the second transport
table 105. Hereby the compressible objects 101 or the part thereof closest to the
compression plate 119 are wrapped in foil 111, 113. The first set of upper 115 and
lower spears 116 can be seen in this side view.
[0018] The second segment 123 of the compression plate 119 is oriented horizontally and
the first segment 121 is sloping downwards relative to the conveying direction. That
is, the end of the first segment 121 facing the second foil 113 is positioned higher
relative to the end of the first segment 121 facing the second segment 123 of the
compression plate 119.
[0019] Figure 3a-d illustrate the steps by which the compression plate 119 is utilized in
the packaging process.
[0020] In figure 3a, a number of bundled and packed compressible objects 101 are placed
and gathered on the first transportation table 103. When gathered, the pushing device
109 pushes the objects 101 from the first transportation table 103, through the foil
111,113 and into the space defined by the second transportation table 105, the fence
107 and the compression plate 119. At this point of time in the process, the second
segment 123 of the compression plate 119 is oriented horizontally and the first segment
121 is sloping downwards relative to the conveying direction. That is the end of the
first segment 121 facing the second foil 113 is positioned higher relative to the
end of the first segment 121 facing the second segment 123. Due to the slope of first
segment 121, the second segment 123 can be positioned such that the distance between
the second segment 123 and the transportation table 105 is less than the height of
the objects 101 led in between these two surfaces, whereby the foil 111, 113 is wrapped
tightly around the objects 101.
[0021] As illustrated in figure 3b, when the movement of the compressible objects 101 is
stopped by the fence 107, the sides of the compressible objects 101 facing the compression
plate 119, the fence 107 and the second transportation table 105 are covered with
the foil 111, 113. Hereafter the sloped first segment 121 is pivoted to a horizontal
position, whereby the first segment 121 and the second segment 123 constitute one
plane. Next, the lower set of spears 116, 118 are moved towards each other, so that
they block the open end of the compressible objects 101 not yet covered by foil 111,
113. The compression plate 119 is then moved downwards, so that all compressible objects
101 are compressed uniformly.
[0022] Depending on the height of the compressible objects 101, the upper set of spears
115, 117 may be moved towards each other simultaneously with the lower set of spears
116, 118, so that the former block the upper part of the compressible objects 101
not yet covered by foil 111, 113.
[0023] As illustrated in figure 3c, the first segment 121 of the compression plate 119 is
then pivoted such that the end of segment 121 facing the foil 111, 113 is moved downwards,
whereby the parts of the compressible objects 101 placed under first segment 121 are
further compressed. Hereafter the welding bars 127, 129 are moved together and the
foil 111, 113 welded and cut.
[0024] In one embodiment of the invention, 127 is a knife and 129 is an opening, into which
the knife 127 can slide. In another embodiment of the invention, the reverse is valid,
and in yet another embodiment of the invention, both 127 and 129 are knifes.
[0025] Figure 3d illustrates the final steps in the wrapping process subsequent to the welding
of the foil 111, 113, where the two welding knifes 127, 129 are moved away from one
another and the lower spears 116, 118 withdrawn. Concurrently, the compression plate
119 is moved upwards again, whereby the potential energy of the compressed objects
101 is released, leading to an expansion of the compressible objects 101. This expansion
will continue to the extent allowed by the length of the foil 111, 113 and e.g. the
elastic properties thereof.
[0026] Since the compressible objects 101 have been led in an uncompressed state into the
foil 111, 113 and afterwards compressed, the length of the foil 111, 113 around the
compressible objects 101 is greater than the circumference of the compressible objects
101. The extra compression of the compressible objects 101 performed when turning
the first segment 121 downwards ensures that the foil 111, 113 used to cover the fourth
end of the compressible objects 101 corresponds to the foil 111, 113 used to cover
the end of the compressible objects facing the fence 107.
[0027] When the wrapping process is completed, the compressible objects 101 are transported
along the second table 105 for further transportation/storage. A new set of compressible
objects 301 to be wrapped enters the first transport table 103.
[0028] Figure 4 illustrates an alternative embodiment of the compression plate 400 comprising
three segments 438, 440, 442 and four hinges 430, 432, 434, 436. The compression plate
400 could be made of metal or a flexible material, such as a polymer-based material.
[0029] Figure 5 illustrates yet another embodiment of the compression plate 500, comprising
only one flexible plate 552 and a number of eyelets 550. The eyelets could be connected
to pneumatic actuators (not shown), which would cause the flexible plate 552 to bend
as illustrated in figure 5. This bend of the flexible plate 500 resembles and essentially
fulfils the same purpose as the compression plate 119, 400. The flexible plate 552
could be made of a flexible material such as spring steel, metal sheet of a polymer-based
material.
[0030] The compression plates 119, 400, 500 can exert their compression by means of e.g.
pneumatic, hydraulic or linear actuators.
[0031] In the above examples the packaging machine is used for wrapping square packs of
compressible material, but a similar technique could of course also be used for wrapping
rolls of compressible material or other shapes and resulting in similar advantages.
References
[0032]
100 Packaging machine
101 One or more compressible objects to be packed
103 First transportation table
105 Second transportation table
107 Fence
109 Pushing device
111 First roll of foil
113 Second roll of foil
115 First set of upper spears
116 First set of lower spears
117 Second set of upper spears
118 Second set of lower spears
119 Compression plate
121 Second segment of the compression plate 119
123 First segment of the compression plate 119
125 Hinge
127 Lower welding bar
129 Upper welding bar
301 New set of at least one compressible object to be packed
400 Compression plate
430 Hinge
432 Hinge
434 Hinge
436 Hinge
438 Plate segment
440 Plate segment
442 Plate segment
500 Compression plate
550 Eyelet
552 Flexible plate
1. A packaging machine (100) for packaging at least one compressible object (101) into
foil (111, 113) comprising at least one compression plate (119), where said at least
one compression plate (119) comprises at least two segments (121, 123) which can be
sloped individually, whereby it is obtained that said at least one compressible object
(101) can be unevenly compressed by said compression plate (119) during the packaging
process of said at least one compressible object (101).
2. A packaging machine (100) according to claim 1, where said at least two plate segments
(121, 123) are interconnected by at least one hinge (125).
3. A packaging machine (100) according to claims 1-2, where said compression plate (119)
further comprises at least one hinge (430,436) connected to one of said at least two
plate segments (121, 123).
4. A packaging machine (100) according to claims 1-3, where said compression plate (119)
comprises a flexible plate (552) and at least one eyelet (550) mounted on said flexible
plate (552) for separating said at least two segments of said flexible plate.
5. A packaging machine (100) according to claims 1-4, where said compression plate (119)
compresses said at least one compressible object (101) by pneumatic means.
6. A packaging machine (100) according to claims 1-5, where said compression plate (119)
compresses said at least one compressible object (101) by hydraulic means.
7. A packaging machine (100) according to claims 1-6, where said compression plate (119)
compresses said at least one compressible object (101) by means of linear actuators.
8. A method for wrapping a foil (111, 113) onto at least one compressible object (101),
comprising the steps of
- wrapping at least one side of said at least one compressible object (101) whereby
said foil (111, 113) covers said at least one side
- compressing said at least one compressible object (101) unevenly
9. A method according to claim 8, further comprising the step of
- closing said foil (111, 113) after said at least one compressible object (101) has
been unevenly compressed.