U.S. patent application number 11/641240 was filed with the patent office on 2008-06-19 for transport pallet.
Invention is credited to Anders L. Valentinsson.
Application Number | 20080141912 11/641240 |
Document ID | / |
Family ID | 39525604 |
Filed Date | 2008-06-19 |
United States Patent
Application |
20080141912 |
Kind Code |
A1 |
Valentinsson; Anders L. |
June 19, 2008 |
Transport pallet
Abstract
Pallet for the movement of goods with several individual parts,
which are connected to each other: A loading part 6 comprises a
planar slab and the goods to be transported are placed on a loading
surface 26 of the loading part. Underneath the loading part are
arranged a reinforcement section 5, a frame center section 3 and a
frame floor section 4. A flame protection coating of the individual
parts of the pallet effects fire resistance in the event of a
fire.
Inventors: |
Valentinsson; Anders L.;
(Farlov, SE) |
Correspondence
Address: |
VAN DYKE, GARDNER, LINN & BURKHART, LLP
SUITE 207, 2851 CHARLEVOIX DRIVE, S.E.
GRAND RAPIDS
MI
49546
US
|
Family ID: |
39525604 |
Appl. No.: |
11/641240 |
Filed: |
December 19, 2006 |
Current U.S.
Class: |
108/57.33 ;
108/51.11; 108/57.25 |
Current CPC
Class: |
B65D 2519/00417
20130101; B65D 19/0014 20130101; B65D 2519/00104 20130101; B65D
2519/00791 20130101; B65D 2519/00318 20130101; B65D 2519/00333
20130101; B65D 2519/00348 20130101; B65D 2519/00273 20130101; B65D
2519/00129 20130101; B65D 2519/00407 20130101; B65D 2519/00373
20130101; B65D 2519/0086 20130101; B65D 2519/00069 20130101; B65D
2519/00288 20130101; B65D 2519/00562 20130101; B65D 2519/00442
20130101; B65D 2519/00034 20130101 |
Class at
Publication: |
108/57.33 ;
108/51.11; 108/57.25 |
International
Class: |
B65D 19/32 20060101
B65D019/32; B65D 19/38 20060101 B65D019/38 |
Claims
1. A pallet for the movement of goods, comprising: an upper section
having a loading part with a loading surface and a reinforcement
section, wherein the loading surface and the reinforcement section
have a material-fit connection to each other; a frame section
comprising a frame center section and a frame floor section,
wherein the frame center section and the frame floor section are
connected to each other; wherein the frame center section
corresponds to the size of the loading surface and, at least at its
corners, has spacers, which point to the upper section and have a
material-fit connection via the frame section to the upper section,
wherein the spacers have end-face elevations inwardly offset
stepwise, and the reinforcement section has, at its lower surface,
recesses for accommodating the elevations; and wherein the frame
center section has a material-fit connection to the reinforcement
section in the area of at least one of the spacers and the end-face
elevations.
2. The pallet in accordance with claim 1, wherein the loading part,
the reinforcement section, the frame center section and the frame
floor section are formed from plastic.
3. The pallet in accordance with claim 2, wherein at least a first
welding rib is molded to the end faces of the spacers, wherein the
at least one welding rib points toward the reinforcement section
and serves as welding material during welding of the frame center
section to the reinforcement section.
4. The pallet in accordance with claim 2, wherein at least a second
welding rib is molded to the end faces of the elevations, wherein
the at least one welding rib points toward the reinforcement
section and serves as welding material during welding of the frame
center section to the reinforcement section.
5. The pallet in accordance with claim 4, wherein at least a third
welding rib is provided at the reinforcement section in the area of
the recesses for welding the frame center section to the
reinforcement section.
6. The pallet in accordance with claim 5, wherein the third welding
rib is comprised of multiple parts.
7. The pallet in accordance with claim 2, wherein the reinforcement
section is adapted to be produced in a thermoforming process.
8. The pallet in accordance with claim 2, wherein the upper surface
of the loading part is planar.
9. The pallet in accordance with claim 2, wherein the reinforcement
section is tub-shaped and includes a tub floor, wherein the open
side of the reinforcement section is limited by the loading part,
wherein, in the area of the tub floor, a plurality of rib-like
elevations is formed, said plurality of rib-like elevations being
in contact with the loading part.
10. The pallet in accordance with claim 1, wherein the upper
section has a plurality of handle openings.
11. The pallet in accordance with claim 10, wherein the loading
part and the reinforcement section have a material-fit connection
in the area of the handle openings.
12. The pallet in accordance with claim 2, wherein an outwardly
sealed transponder cavity is provided at the pallet in the area of
the spacers for accommodating a transponder, wherein at an exterior
surface of the transponder cavity, the wall thickness is reduced at
least from area to area.
13. The pallet in accordance with claim 2, wherein the
reinforcement section has an impact reinforcement in the area of a
side wall of the reinforcement section, wherein said reinforcement
section is formed to be corrugated or rib-like at least from area
to area.
14. The pallet in accordance with claim 2, wherein handle recesses
are provided at the reinforcement section.
15. The pallet in accordance with claim 2, wherein the
reinforcement section comprises at least one anti-slipping rim for
limiting slipping of goods present on the loading surface, said rim
projecting over the upper side of the loading part.
16. The pallet in accordance with claim 15, wherein at least one
anti-slipping rim recess is formed in the frame foor section,
wherein a further pallet may be received in the recess during
stacking of the anti-slipping rim.
17. The pallet in accordance with claim 1, wherein the pallet
comprises at least four stiffening profiles made of metal.
18. The pallet in accordance with claim 1, wherein the frame
section has at least four bar-like carriers, wherein stiffening
profiles are arranged in the bar-like carriers.
19. The pallet in accordance with claim 1, whewrein a coating of a
flame-retarding material is applied at least on areas of the
surface of the loading part, the reinforcement section and the at
leastone of the frame center section and the frame floor
section.
20. The pallet in accordance with claim 19, wherein a
flame-retarding material is incorporated in at least one outwardly
sealed area between the loading part and the reinforcement section
and between the frame center section and the frame floor
section.
21. The pallet in accordance with claim 2, wherein the
reinforcement section is producible in a thermoforming process.
22. The pallet in accordance with claim 2, wherein the upper
surface of the loading part is planar.
23. The pallet in accordance with claim 2, wherein the
reinforcement section is tub-shaped and includes a tub floor,
wherein the open side of the reinforcement section is limited by
the loading part, wherein a plurality of rib-like elevations is
formed in the area of the tub floor, said plurality of rib-like
elevations being in contact with the loading part.
24. The pallet in accordance with claim 3, wherein the
reinforcement section is producible in a thermoforming process.
25. The pallet in accordance with claim 3, wherein the upper
surface of the loading part is planar.
26. The pallet in accordance with claim 3, wherein the
reinforcement section is tub-shaped and includes a tub floor,
wherein the open side of the reinforcement section is limited by
the loading part, wherein, in the area of the tub floor, a
plurality of rib-like elevations is formed, said plurality of
rib-like elevations being in contact with the loading part.
27. The pallet in accordance with claim 4, wherein the
reinforcement section is adapted to be produced in a thermoforming
process.
28. The pallet in accordance with claim 4, wherein the upper
surface of the loading part is planar.
29. The pallet in accordance with claim 4, wherein the
reinforcement section is tub-shaped and includes a tub floor,
wherein the open side of the reinforcement section is limited by
the loading part, wherein, in the area of the tub floor, a
plurality of rib-like elevations is formed, said plurality of
rib-like elevations being in contact with the loading part.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to a pallet for the
movement of goods.
BACKGROUND OF THE INVENTION
[0002] For the transport of goods, transport pallets, especially
Euro pallets, are well-known, which are traditionally made of wood.
Furthermore, pallets manufactured from plastic are also common,
which, in addition to having a low weight, have better resistance
to aging and are better to clean in comparison to wood. Many
well-known pallets, however, have a relatively low torsional
rigidity. They therefore cannot be readily subjected to asymmetric
heavy loads. This reduces the scope of application.
[0003] Furthermore, the problem arises in the case of plastic
pallets that the plastic is flammable such that, in the event of a
fire, toxic gases can develop. This, too, leads to a fundamentally
undesirable restriction on the pallet's scope of application.
[0004] The object of the present invention is to create a pallet
whose scope of application is increased.
SUMMARY OF THE INVENTION
[0005] The pallet described here has an upper section and a frame
section, wherein the upper section has a loading part with loading
surface and a reinforcement section that have a material-fit
connection to each other. The frame section comprises a frame
center section and a frame floor section, which likewise have a
material-fit connection to one another. Furthermore, the frame
center section corresponds to the size of the loading surface and,
at least at its corners, has spacers which point toward the upper
section and via which the frame center section is connected to the
upper section. At their end faces, the spacers have elevations
which are inwardly offset in steps. For accommodating these
elevations, the reinforcement section has recesses at its lower
surface. The frame center section likewise has a material-fit
connection to the reinforcement section in the area of the end-face
spacers. Alternatively or additionally, the aforementioned
connection can be in the area of the elevations. The pallet in
accordance with the invention is substantially torsionally stiffer
than well-known pallets, because the upper section and the frame
section reinforcing it are much better connected to one another.
This increases its scope of application such that it is more
economically applicable.
[0006] The loading part, the reinforcement section, the frame
center section and the frame floor section are preferably made from
plastic, especially an elastomer plastic, with a material such as
polypropylene or polyethylene suitable for use. Parts made from
such a plastic lend themselves readily to material-fit connections.
The aforementioned connections between the parts are of a
material-fit type effected by a welding method, with hot-plate
welding especially suitable. Hot-plate welding is one of those
heating element welding methods in which heating elements heat the
contact area to be welded until the material in the areas concerned
softens, and then the heating elements are removed from the heated
area. The components to be welded are then positioned against each
other and aligned with each other under compressive force. Material
in the area to be welded deforms fluidly and, in flowing, creates
the material connection. Preferably, heating is performed not as
far as the melting point of the plastic, but only to above the
softening point.
[0007] For the purpose of supporting the welding process, at least
a first welding rib is molded on to the spacers at the end face,
said rib pointing toward the reinforcement section and serving as
welding material during welding of the frame center section to the
reinforcement section. The first welding rib of the spacer is
advantageously closely molded on at a peripheral outside edge of
the spacer and points upward and away from the frame center
section. The rigidity of the connection is increased by the outer
welding rib.
[0008] Further, at least a second welding rib is molded on
advantageously at the end face of the elevations, said rib pointing
toward the reinforcement section and serving as welding material
during welding of the frame center section and the reinforcement
section. The first and second welding ribs both have the same
alignment, which is parallel to the loading surface. Thus, the
welding planes defined by the first and second welding ribs are
accordingly parallel to the loading surface. The second welding rib
is thereby arranged closer to the loading surface than the first
welding rib. Due to this vertical offset, correspondingly offset
welding regions are produced, which, through their different
positioning, serve to improve retention of the elevations in the
recesses. Furthermore, the lateral gap between the elevation and
the recess is advantageously dimensioned, such that a part of the
material of the second welding rib flows into this area in order to
yield a weld at a side that is not the end face of the
elevation.
[0009] In a development in the area of the recesses at the
reinforcement section, at least a third welding rib for welding the
frame center section to the reinforcement section is provided .
Advantageously, this third welding rib is multipart. These third
welding ribs are either formed as a rib-like elevations, or
alternatively as incremental elevations. These third welding ribs
are formed such that, during uniting of the reinforcement section
and the frame center section, they press against the softened
material of the second welding rib, and so flow of the material
around the welding ribs is made possible. A good welded joint can
be achieved by this flow around the third welding ribs.
Advantageously, the material of the recess, too, and thus the third
welding rib is heated, with the material able to connect well to
the material of the second welding rib and the elevations. A
corresponding welding process is provided for welding of the first
welding rib to the reinforcement section, as well for the other
aforementioned material-fit connections.
[0010] The loading part has advantageously an essentially flat
surface at the upper surface and has especially the shape of a flat
slab, such that the loading part can be cut out from an extruded
flat slab. Since the material becomes thermoplastic during the
extrusion process, clearly better values for strength are
attainable than is the case for an injection molded material under
given comparable material thicknesses. Thus, the loading surface,
which corresponds to the surface of the loading part, has good
mechanical properties, such that it is not damaged by transport
goods that are placed on the loading surface.
[0011] The reinforcement section is arranged underneath the loading
part. It is essentially tub-shaped, with the open side of the tub
limited by the loading part. The depth of the tub, that is, the
distance in the vertical direction, is a few centimeters and the
tub floor forms a plane that is parallel to the loading part. At
the reinforcement section in the area of the tub floor, a plurality
of rib-like elevations are molded on, which point toward the
loading part and are in contact with it. Furthermore, the recesses
at an area of the tub floor are molded on such that the vertical
ends of the recesses are in contact with the loading part.
[0012] In this regard, the reinforcement section is preferably
designed such that it is manufacturable in a thermoforming process.
In the thermoforming process, starting from a plastic slab, the
three-dimensional structure is created, which substantially effects
the stability of the upper section.
[0013] Preferably, the reinforcement section has a material-fit
connection at the aforementioned contact areas with the loading
part. By means of reinforcement section ribs, connections from the
loading part to the reinforcement section at a plurality of points
or areas are produced, which provides a three-dimensional
structure, which effects high strength for the upper section of the
pallet. The reinforcement section ribs, which are located between
two recesses, are aligned such that they point in the longitudinal
direction from one recess to the next.
[0014] The upper section preferably has a plurality of handle
openings. Expediently, the connection from the loading part to the
reinforcement section in the area of the handle openings is a
material-fit connection. So that workers do not hurt their hands
when handling the pallet, it is advantageous if the handle openings
arranged in the upper section are rounded.
[0015] At the pallet, preferably an outwardly sealed transponder
cavity is provided for accommodating a transponder in the area of
the spacers. Furthermore, at an exterior surface of the transponder
cavity, the wall thickness of the pallet is at least locally
reduced. The transponder cavity is outwardly sealed in order that
no harmful environmental influences, such as damp, may penetrate
and damage the electronics of the transponder. Further, at an
exterior side of the transponder cavity is provided an area of
smaller wall thickness, which advantageously corresponds to the
lower surface of the pallet, such that, for example, the material
there can be removed with a knife in order that an opening may be
created through which the transponder can be replaced. A
replacement of this kind may be necessary if, due to technical
changes, for example, new transponders or altered specifications, a
transponder, which was already inserted into the transponder cavity
during production of the pallet, can no longer be used. If a
transponder is replaced via the window in the frame floor section,
the transponder cavity can be sealed by a plastic molding compound
in order that the replaced transponder may be protected from
environmental influences.
[0016] Preferably, the reinforcement section in the area of its
side wall has an impact reinforcement, areas of which at least are
formed so as to be corrugated or ribbed. The impact reinforcement
advantageously leads, starting from the floor surface of the
tub-shaped form of the reinforcement section, upwardly to as far as
the edges of the reinforcement section that are in contact with the
loading part. The corrugations lie in a plane that is parallel to
the loading surface. The shape of the impact reinforcement ensures
that the impact strength is increased, a fact which is essential if
the pallet experiences jerky lateral loads, for example, during
transport or when grabbed by the tines of a fork-lift truck or a
lifting truck.
[0017] Furthermore, handle recesses are provided advantageously at
the reinforcement section. These are expediently arranged at the
reinforcement section in the area of the transport openings, such
that they are arranged at a slight distance from the side wall at
which the impact reinforcement is molded on. The handle recesses
comprise an indentation, which is at least as wide as a human
hand.
[0018] Preferably, the reinforcement section has an anti-slipping
rim that projects over the upper surface of the loading part and
serves to limit slipping of goods present on the loading surface.
The bulk of the reinforcement section is underneath the loading
part in the vertical direction. However, some bar-like areas of the
reinforcement section preferably are molded on such that they
terminate above the loading part at the sides. Thus, for example,
an interrupted bar which has a uniform height of, for example, 1
cm, can be created at the outside edge of the loading surface.
Goods might slip on the loading area due to transport forces, but
this slippage is limited by the anti-slipping rim. Advantageous in
this regard is that the anti-slipping rim is easily producible,
does not require a separate part and also lends itself to better
stacking of several pallets. It is advantageous that the
anti-slipping rim is formed as a component of the reinforcement
section, since as such it is more readily and economically
producible, a fact which would not be obtained if it were a
component of the loading part, which is preferably manufactured by
extrusion.
[0019] For the purpose of easy stacking of several pallets one
above the other, corresponding anti-slipping rim recipients are
molded on at the frame floor section, in which the anti-slipping
rim of a further pallet may be accommodated. This offers advantages
in the stacking of several pallets since alignment and
immobilization of pallets lying one on top of the other is
achieved.
[0020] The pallet has preferably four bar-like carriers in which
stiffening profiles are arranged. These carriers form the framework
of the frame section. The frame section has preferably four
large-area rectangular floor break-throughs. In the bar-like areas,
which limit the floor break-throughs, stiffening profiles can
preferably be arranged. These recipient areas for the stiffening
profiles are located in the area of the contact surface of the
frame center section and frame floor section.
[0021] These stiffening profiles can be rectangular or square
hollow sections made from a metal, especially steel, and serve to
increase the torsional rigidity of the pallet. A plastic profile
resistant to bending is also conceivable.
[0022] Advantageously, the stiffening profiles are provided in the
frame of the frame section described by the external form of the
pallet, with one profile provided per edge. A further profile can
be provided in one of the edges of the central crosspiece of the
frame section, as a result of which therefore four or five
stiffening profiles result. The stiffening profiles can be
economically inserted as individual parts into the frame sections
independently of each other. They can, however, also be welded to
one another, which further increases the rigidity.
[0023] The pallet has in an advantageous embodiment a coating of
flame-retarding material, which is applied at least on areas of the
surface of the loading part, the reinforcement section, the frame
center section and/or the frame floor section. Pallets, especially
plastic pallets, whose plastic material contains a flame-retarding
additive, are well-known. However, incorporation of the
flame-retarding material into the plastic causes the disadvantage
that physical properties such as hardness and breaking strength are
adversely affected. Thus it is advantageous, in contravention to
convention, for the flame protection to be applied via a
coating.
[0024] The pallet has, as described, a plurality of plastic parts,
which have in turn a plurality of ribs. The result is a large
overall surface, which can be coated accordingly. Advantageously,
especially those surfaces will be provided with the coating which
are exposed to little or no mechanical load. The coating can be
applied both to the individual parts before welding and to the
finished pallet after welding. The coating works on one hand as a
direct protection for the coated plastic material since the
material cannot be so easily reached by the fire. On the other,
there is an advantage in the fact that, in this manner, the
flame-retarding material inhibits the fire overall in the vicinity
of the fire. This means that, if, for example, one part of a
warehouse with the pallets is on fire, the flame-retarding material
causes the fire to be generally inhibited, such that it spreads
more slowly and is easier to extinguish. This also applies if
interior surfaces are coated, by which is meant the surfaces
between the loading part and reinforcement section and between
frame center section and the frame lower section. Thus, the pallet
is highly suitable in fire-risk areas or for transporting readily
flammable materials.
[0025] Further, a flame-retarding material can, for example, be
incorporated as a kind of foam, at least in an outwardly sealed
space between the loading part and the reinforcement section and
between the frame center section and the frame floor section. The
aforementioned enclosed space can be between the loading part and
the reinforcement section or between the frame center section and
the frame floor section. A material with flame-retarding
characteristics can be incorporated into both areas before the
individual parts of the pallet are welded. If the pallet is in a
fire, the plastic material of the pallet melts or burns and the
flame-retarding material is released to thus limit burning of the
pallet and the fire overall.
[0026] Coatings containing urethane are especially suitable as
material for coating the surfaces of the pallet. Also, a foam that
contains urethane can be incorporated into an outwardly sealed area
of the pallet. Furthermore, the flame protection can also be
achieved by means of inorganic flame protection agents, halogenated
flame protection agents, such as those based on chromium or
bromine, or organophosphorous agents or by means of nitrogen
compounds.
[0027] The following drawings show the preferable embodiment,
without limiting the inventive idea expressed in the claims. These
and other objects, advantages, purposes and features of the present
invention will become apparent upon review of the following
specification in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a three-dimensional view of the pallet in the
position of normal use, wherein the loading surface points
upward,
[0029] FIG. 2 is a corresponding three-dimensional lower view of
the pallet,
[0030] FIG. 3 is a partly exploded view of the pallet, in which the
reinforcement piece and loading part are not exploded toward each
other,
[0031] FIG. 4 is a rotated view of the exploded view in accordance
with FIG. 3,
[0032] FIG. 5 is a plan view of a quarter of the frame center
section, with the lower right corner shown,
[0033] FIG. 6 is a cross-sectional view on the line D-D of FIG. 5
through one of the elevations 9,
[0034] FIG. 7 is a detailed view of FIG. 6 with the representation
of the second welding ribs,
[0035] FIG. 8 is a detailed view of FIG. 6 of the welding ribs for
welding of frame center section to the frame floor part,
[0036] FIG. 9 is a detailed view of the FIG. 6 of the first welding
ribs,
[0037] FIG. 10 is a cross-sectional view on the line E-E of FIG.
5,
[0038] FIG. 11 is a cross-sectional view on the line A-A of FIG.
5,
[0039] FIG. 12 is a cross-sectional view on the line B-B of FIG.
5,
[0040] FIG. 13 is a cross-sectional view on the line C-C of FIG.
5,
[0041] FIG. 14 is a detailed view of FIG. 13 of the welding ribs
for welding the frame center section to the frame floor
section,
[0042] FIG. 15 is a plan view of a quarter of the frame center
section, with the lower right corner shown,
[0043] FIG. 16 is a cross-sectional view on the line F-F of FIG.
15,
[0044] FIG. 17 is a detailed view of FIG. 16,
[0045] FIG. 18 is a cross-sectional view on the line B-B of FIG.
15,
[0046] FIG. 19 is a detailed view of detail G of FIG. 20, and
[0047] FIG. 20 is a cross-sectional view on the line E-E of FIG.
15.
DETAILED DESCRIPTION OF THE DRAWINGS
[0048] FIG. 1 is a three-dimensional view of a pallet in accordance
with the invention 1, whose loading surface 26 points upward. In
the following, it is this definition of the direction which is
referred to. The loading surface 26 is an area of the loading part
6, which, together with the reinforcement section 5, forms the
upper section 2 of the pallet 1. Underneath the upper section 2 is
arranged the frame section 40, which comprises the frame center
section 3 and the frame floor section 4. The frame section 40 has a
rectangular basic structure, which corresponds roughly in size to
the loading surface 26, and in this basic structure are provided
four wide, window-like break-throughs, such that the frame section
40 has essentially four external struts and a central crosspiece
42, as evident in FIG. 2. Underneath the frame center section 3 is
the frame floor section 4, which is connected to the frame center
section 3 and has a platform for the surface. Stiffening profiles
7a, 7b are accommodated in the area between frame center section 3
and frame floor section 4.
[0049] Upper section 2 has four handle openings 28, which are long
enough and wide enough for a worker to put in a hand to comfortably
lift the unloaded pallet. The alignment of the handle openings 28
in their length corresponds to the longitudinal direction of the
rectangular pallet 1. The handle openings are arranged at the edge
of the upper section 2.
[0050] As is evident from FIG. 3, the upper section 2 is of uniform
thickness, which is created by the distance from the loading part 6
to a parallel arranged base surface of the reinforcement section 5.
At the sides of this base surface are provided essentially
perpendicularly arranged edges, which point toward the loading part
6 and are connected to this. Viewed in this way, the reinforcement
section 5 has a tub-shaped basic structure, with the open side of
the tub limited by the loading part 6. At the outer peripheral
contact area between reinforcement section 5 and the loading part 6
are provided areas upon which the loading part 6 on the
reinforcement section 5 rests. In other words, the contact surface
here is horizontally aligned such that gravity forces from goods
present on the loading part 6 are transmitted direct via
compressive forces to reinforcement section 5. These areas are
arranged at the corners of the pallet and at the center of their
sides. On areas located between them are arranged anti-slipping
rims 25, which are a component of the reinforcement section 5,
arranged such that they terminate above the loading area 26. The
contact surface between the reinforcement section 5 and the loading
part 6 has a vertical alignment there. The loading surface 26 is
limited at each of its sides by two anti-slipping rims 25.
[0051] In FIG. 3, it is clear that the reinforcement section 5
comprises a plurality of reinforcement section ribs 41, which,
starting from the base surface of the reinforcement section 5,
point toward to the loading part 6, have a longitudinal extension
and are in contact with the loading part 6. At the contact areas
between the loading part 6 and the reinforcement section 5 is
provided a material-fit connection, a fact which means that the
material of both parts is welded in these areas. Through the welds,
the loading part 6 and the reinforcement section 5 enclose an area,
which is designed to be dampproof.
[0052] The view of the lower side of the pallet in FIG. 2 clearly
shows the central crosspiece 42 of the frame section 40. It extends
centrally in the frame, which is spanned by the four corners of the
pallet 1. The central crosspiece 42 as well as the lower area of
the frame section 40 are formed from the frame center section 3 and
the frame floor section 4. As FIG. 3 shows, in areas between the
frame floor section 4 and the frame center section of 3 are
arranged two stiffening profiles 7a and three stiffening profiles
7b, with two each of the profiles 7a and 7b in the outside edges of
the framework and a profile 7b in an axis of the central crosspiece
42. The stiffening profiles 7a and 7b are manufactured from a
rectangular steel section. At the lower side at the frame center
section 3 are provided center section profile recipients 43, which
are U-shaped. As shown in FIGS. 10, 11 and 12, center section
profile recipients 43 are roughly the width of the stiffening
profiles 7a or 7b and half their height. Each of the stiffening
profiles 7a and 7b is fitted into the profile recipient 43 such
that approximately half of the height projects above the center
section profile recipient 43 and is accommodated in a profile
recipient 45--see FIG. 18--of the frame floor section 4.
Furthermore, for the purpose of lateral guidance of the stiffening
profiles 7a, 7b, ribs 46 are molded on at the frame center section
ribs 44 and at the frame floor section, said ribs 46 limiting the
lateral mobility of the profiles. Since the ribs 44 deform flexibly
when the stiffening profiles 7a and 7b are joined to the frame
center and floor sections, the stiffening profiles are accommodated
without any play and so can easily accommodate twisting of the
pallet and thus support the rigidity of the pallet. Additionally,
the frame center and floor sections are aligned relative to each
other via the stiffening profiles 7a and 7b during joining in the
production process.
[0053] At the frame center section 3 are molded on nine spacers 27,
which contact its four corners, four centers of its outside edges
and the center of its surface. As evident from FIG. 4 or FIG. 6,
provided at the spacers 27 are elevations 9, which are present at
an end face of the spacers and are inwardly offset stepwise. Both
the spacers 27 and the elevations 9 are essentially rectangular,
with the length and width of the elevations 9 smaller than those of
the spacers 27. FIG. 6 shows that the elevation 9 has a truncated
pyramid extension. Reinforcement piece 5 has corresponding recesses
8, in which the elevations 9 are accommodated. Here, the truncated
pyramid shape facilitates joining of the frame center section to
the reinforcement section in the manufacturing process, since both
parts position themselves relative to each other via the diagonal
edge.
[0054] FIG. 4 or 6 shows how first welding ribs 31 are molded on at
the spacer 27, and second welding ribs 32 are molded on at the end
of the elevation 9. Both, the first and second welding ribs, are
each molded on at the end-face outside edges of the spacer 27 and
the elevations 9. During welding of frame center section 3 to the
upper section 2, the ribs 31 and 32 are heated to the softening
point, then the two parts are joined to each other. During joining,
mechanical pressure is exerted on the first and second welding ribs
31 and 32, such that these ribs deform fluidly, such that this flow
creates a material-fit connection between the two parts. This
process is supported by third welding ribs 33, which are shown in
FIG. 3. The third welding ribs 33 are at the base of the recesses 8
and make contact with the second welding ribs 32 during joining.
Since the third welding ribs 33, unlike the second welding ribs 32,
are not formed continually around the periphery, but project from
area to area, the material of the second welding ribs 32 can flow
around the third welding ribs 33 during joining, whereby the
strength of the welded joint can be improved.
[0055] FIG. 5 shows a plan view of the lower right corner of the
frame center section 3, which shows only one of the four windows of
the frame center section 3. In the lower right corner of FIG. 5 is
shown a plan view 5 of the spacer 27, which, in cross-sections
along lines D-D, in accordance with FIG. 6, and C-C, in accordance
with FIG. 5, is shown in detail in both side views.
[0056] FIGS. 7 and 9 show the shape of the welding ribs 32 and 31
in details G and J. At those areas where the ribs at the elevation
9 or the spacer 27 are molded on is provided one each of a material
accumulation 48, which has a larger wall thickness than the
corresponding welding rib 31 and 32. In the welding method,
temperature control ensures that primarily the material of the
welding ribs is softened. Since, in the area of the material
accumulation 48, the heat supplied is insufficient to soften the
material, during welding, this area, and thus also elevations 9 and
the spacers 27, remain undeformed as far as possible and material
softening is limited to the welding ribs.
[0057] In FIG. 8, a fourth welding rib 49 of the frame center
section 3 is shown, which serves for welding to the frame floor
section 4. Peripheral fourth welding ribs 49 are each arranged
around one of the window-like break-throughs, such that the frame
center section 3 and the frame floor section 4 at these welding
seams can be connected to each other continuously and thus to be
impermeable to damp.
[0058] FIGS. 11 and 12 show the cross-sections along lines A-A and
B-B of FIG. 5 with a part of the frame of the frame section 40, the
center section profile recipients 43 and corresponding ribs 44,
which serve the purpose of guidance of the ribs shown. FIG. 13
shows a section through the frame center section 3, whose detail H
in FIG. 14 shows a fourth welding rib 50. This is arranged
peripherally at the outside edge of the frame center section 3 and
makes for a dampproof weld to the frame floor section 4 in this
area.
[0059] FIG. 15 shows a plan view of the lower right quarter of the
frame floor section 4, and the section in accordance with FIG. 16
with the detail K in accordance with FIG. 17 shows a groove 47,
which is molded on at the lower surface of the frame floor section
4. This groove 47 is rectangular, as shown in FIG. 3, and forms an
area in which the wall thickness of the frame floor section 4 is
reduced. This groove 47 thus delimits in other words a window 10,
behind which extends toward the spacer 27 an inner space as
transponder cavity 11, which is suitable for accommodating a
transponder. Before the frame center section 3 is welded to the
floor section 4, a transponder is inserted into this transponder
cavity 11, said transponder being then enclosed by welding so as to
be dampproof. Only when, for example, a cut is made with a knife
along the groove 47, is the window 10 opened, such that access to
the inserted transponder is made possible. In this way, the
transponder can be removed and replaced, for example. Then,
plastic, such as a plastic foaming compound, can be used to seal
the window again in order that harmful environmental influences may
be kept at bay from the transponder. At each of the spacers 27,
which lie at the corners of the pallet, is provided a transponder
cavity.
* * * * *