TREA

Pallet with a base plate and legs of metal

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Information

  • Patent Grant
  • 6769367
  • Patent Number
    6,769,367
  • Date Filed
    Tuesday, February 12, 2002
    22 years ago
  • Date Issued
    Tuesday, August 3, 2004
    20 years ago
Information
Abstract
A pallet includes a base plate of cantilever construction and legs of metal, particularly as an underframe for pallet containers for transporting and for storing liquids in an inner container of synthetic material standing on the base plate of the pallet, and an outer casing composed of a grid structure or sheet metal material attached to the base plate. The base plate and the legs of the pallet are manufactured as a single piece from a sheet metal plate as the initial material by deformation, particularly by deep-drawing and/or pressing or by hydroforming.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a pallet with a base plate and legs of metal, particularly as an underframe for pallet containers for transporting and for storing liquids in an inner container of synthetic material standing on the base plate of the pallet, and with an outer casing composed of a grid structure or sheet metal material attached to the base plate.




2. Description of the Related Art




In the past, metal pallets were manufactured as welded metal section or metal pipe constructions or of deep-drawn components and metal sections. As a rule, the welded metal constructions have a high weight and are very difficult and complicated to manufacture. The lightweight constructions of deep-drawn components usually have a low structural strength and they are difficult to stack and to transport. In most lightweight constructions of deep-drawn components, the pallet legs are formed by cup-shaped deep-drawn components which are closed towards the outer side of the pallet. The strength of the pallet is ensured primarily by a closed basic pallet construction to which the pallet legs are welded. The connections of the pallet legs to the base plate of the pallet and to the outer casing of a grid structure or sheet metal material in a pallet container equipped with an inner container of synthetic material are usually screw connections. This type of construction does not make it possible to provide, or makes it difficult to provide, pallets of metal with skid rails because the pallet legs are not constructed as structural supporting members. It is technically very difficult to provide an improved connection of the pallet legs to the base plate. In addition, assembled pallets are difficult to stack and transport because they cannot be nested. Finally, a weight-saving basic pallet construction of synthetic material or wood has in the past not been manufactured for pallet containers because of the insufficient inherent stability of the pallet legs.




SUMMARY OF THE INVENTION




Therefore, it is the primary object of the present invention to develop a metal pallet which has a high stability while having a low weight, and which can be stacked in an optimum manner and makes it possible to manufacture a wide variety of types of basic pallet constructions.




In accordance with the present invention, the base plate of cantilever construction and the legs of the pallet are manufactured as a single piece from a sheet metal plate as the initial material by deformation, particularly by deep-drawing and/or pressing or by hydroforming.




The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages, specific objects attained by its use, reference should be had to the drawing and descriptive matter in which there are illustrated and described preferred embodiments of the invention.











BRIEF DESCRIPTION OF THE DRAWING




In the drawing:





FIG. 1

is a perspective view of a pallet with partially open legs and a base frame;





FIG. 2

is a perspective view, corresponding to

FIG. 1

, showing the pallet without base frame;





FIG. 3

is a perspective view of a sheet metal plate used for manufacturing the pallet according to

FIGS. 1 and 2

;





FIG. 4

is a perspective view of a base plate with open legs for a pallet;





FIG. 5

is a perspective view of a base plate of

FIG. 4

whose legs are covered with cover plates;





FIGS. 6

to


8


are perspective views showing different embodiments of sheet metal plates for manufacturing base plates with legs for pallets;





FIG. 9

is a perspective view of a pallet with skid rails;





FIG. 10

is a sectional view of a base plate with different thicknesses; and





FIG. 11

is a perspective view of a base plate with a plastic container and lattice cladding.











DESCRIPTION OF THE PREFERRED EMBODIMENTS




The principal components of the pallet


1


according to

FIG. 1

are an upwardly arched base plate


2


, four corner legs


3


to


6


and four middle legs


7


to


10


of sheet steel and a base frame


11


made of steel pipe and attached to the corner legs and middle legs


3


to


10


.




The base plate


2


of cantilever construction as well as the four corner legs


3


to


6


and the four middle legs


7


to


10


of the pallet


1


, with base frame


11


according to FIG.


1


and without base frame according to

FIG. 2

, are deep-drawn as a single piece from a sheet metal plate


12


shown in

FIG. 3

, wherein the cup-shaped four corner legs


3


to


6


and the three middle legs


7


to


9


at the two longitudinal sides


2




a


,


2




b


and the rear side


2




c


of the base plate


2


are closed to the side and bottom and are open towards the top. The middle leg


10


at the front side


2




d


of the base plate


2


is open towards the top and towards the front.




The base plate


2


has four stiffening ribs


14


extending from the corner legs


3


to


6


towards the central plate portion


13


and an additional edge stiffening rib


18


which extends along the two longitudinal sides


2




a


,


2




b


, the rear side


2




c


and the front side


2




d


of the base plate


2


and completely or partially through the corner and middle legs


3


to


10


.




The base plate


2


of the pallets


1


according to

FIGS. 1 and 2

additionally has a bridge-like stiffening portion


19


formed of parallel stiffening ribs


20


in the base plate


2


, wherein the stiffening ribs


20


extend from the middle section


21


of the longitudinal side


2




a


through the central plate portion


13


to the middle section


22


of the oppositely located longitudinal side


2




b


of the base plate


2


, and wherein the middle legs


7


,


9


are integrated in the bridge-like stiffening portion


19


.




The base plate


23


according to

FIG. 4

which is deep-drawn from a sheet metal plate


12


has open corner legs and middle legs


3




a


-


6




a


,


7




a


-


10




a


which, as illustrated in

FIG. 5

, are covered by cover plates


24


to


26


.




The flat sheet metal plate


12


according to

FIG. 3

which is used for deep-drawing the base plate


2


and the legs


3


to


10


for the pallets


1


according to

FIGS. 1 and 2

as a single piece has different plate sections


27


to


29


with different thicknesses for obtaining different strength values and to adjust to the different load zones of the base plate


2


.




This optimization of the sheet metal structures, which is also known under the term tailored blanking, is carried out in order to achieve a cost-saving production of the structural components while simultaneously improving the product. Sheet metal plates


12


with different thickness sections for manufacturing base plates


2


with legs


3


to


10


are produced by flexible rolling in which the adjustment of the roll gap during the rolling process is controlled in accordance with the desired plate thicknesses.




Moreover, for manufacturing base plates


2


with legs


3


to


10


it is also possible to use sheet metal plates


30


in accordance with

FIG. 6

which are composed of welded-together sheet metal sections


31


to


33


with different thicknesses in accordance with the different load zones of the base plates


2


.




The sheet metal plates


30


can also be composed of welded-together sheet metal sections


31


to


33


having different material compositions depending on the different load zones of the base plates


2


.




The sheet metal plate


34


according to

FIG. 7

used for the single-piece manufacture of base plates


2


with legs


3


to


10


as shown in

FIGS. 1 and 2

is provided with pre-shaped stiffening ribs


20


of the bridge-like stiffening portion


19


.




The sheet metal plate


35


according to

FIG. 8

for manufacturing base plates


2


with legs


3


to


10


is composed of a sheet metal section


36


with the preshaped stiffening ribs


20


of the stiffening portion


19


and two flat sheet metal sections


37


which are welded together.




Without the base frame


11


, the pallets


1


according to

FIG. 2

can be stacked in each other.




In the pallet


1


illustrated in

FIG. 9

, skid rails


38


of metal, synthetic material or wood are attached to the legs


3


to


10


.




The pallet


1


with an upwardly arched base plate


2


is preferably used as an underframe for pallet containers


39


for transporting and storing liquids with an inner container


40


of synthetic material placed on the base plate and with an outer cladding


41


of a lattice-work structure or sheet metal material attached to the base plate and the legs, wherein the bottom of the inner container, constructed as a bottom for draining the liquid for completely emptying the pallet container, is adapted to the curvature of the base plate of the pallet.




Moreover, the pallet


1


can also be used with a flat base plate


2


as a transport and storage pallet for goods of various types.




While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.



Claims
  • 1. A Pallet, comprising: a one-piece steel plate that forms a metal cantilever base plate and metal feet as an underframe for pallet containers for transporting and storing liquids; a plastic inner container standing on the base plate; and a lattice-work or sheet material cladding secured to the base plate, the feet including one of open, partially closed and completely closed corner and center feet, and the steel plate having plate portions which are adapted to different stressed regions of the base plate and which have at least one of differing sheet thickness and differing material composition to achieve different mechanical strength properties.
Parent Case Info

This application is a divisional of U.S. application Ser. No. 09/638,092, filed Aug. 11, 2000 now abandoned.

US Referenced Citations (12)
Number Name Date Kind
1741189 Jencks Dec 1929 A
1812218 Powell Jun 1931 A
2123714 Clark Jul 1938 A
2256750 Riemenschneider Sep 1941 A
2463214 Stoner Mar 1949 A
2936986 Joohnson May 1960 A
3776146 Morrison Dec 1973 A
3882796 Andreini et al. May 1975 A
4145974 Fleming et al. Mar 1979 A
4326467 Schleicher et al. Apr 1982 A
4424752 Aberg Jan 1984 A
5367960 Schleicher Nov 1994 A