Information
-
Patent Grant
-
6234087
-
Patent Number
6,234,087
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Date Filed
Friday, January 21, 200025 years ago
-
Date Issued
Tuesday, May 22, 200123 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 108 541
- 108 551
- 108 533
- 108 561
- 108 5111
- 108 5725
- 100 901
- 100 902
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International Classifications
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Abstract
A modular pallet system has two or more pallets, each of which has four legs and which is capable of standing on its own as an independent unit. The pallets are formed to dimensions which are a fraction of conventional pallet sizes, such that one pallet alone serves as a quarter of a standard dimensioned pallet, while two pallets combined serve as a half of a standard dimensioned pallet. Each pallet has tabs and slots on the perimeter edges, with the result that two or more of the small pallets can be assembled into a standard size pallet in an interference fit without tools. The pallets may be produced as single sheet thermoformed or twin sheet thermoformed parts, or could be injection molded or structural foam molded. An adapter may be attached in a snap fit beneath four joined pallets to facilitate interaction between the combined pallets and conventional racks and conveyors, and to facilitate stacking.
Description
BACKGROUND OF THE INVENTION
The present invention relates to pallets in general, and to pallets intended to be delivered to points of retail sale in particular.
Many retail sales establishments receive smaller articles, such as boxes cans, and bottles mounted on pallets. Pallets used in combination with the forklift have produced substantial economies in the movement of goods by providing many different goods with a similar interface, allowing mechanization and unitization of goods.
In the New Economy, substantial reductions in the cost of replenishment of inventory have been achieved by large retailers by cooperating with suppliers to determine and even supply inventories necessary to meet fluctuating demands for goods. By pushing the responsibility for maintaining inventory back to the supplier of a good, and maintaining regional warehouses stocked by suppliers who are supplied with near realtime information on in-store purchases, the costs of the so-called “middle man” has been largely eliminated.
The pressure to reduce the cost of supplying goods continues to drive a search for improvements in distribution and retailing. One approach often employed by discount retailers is to stock and sell retail products directly off pallets, thus eliminating or reducing the cost of stocking goods to shelves. This technique of selling retail directly from pallets is being used on a selected basis by larger grocery stores and other mainline retailers.
Often when a retailer requires less than a full pallet load of goods, it is necessary to break down the full pallet into fractional pallet loads by unloading the larger pallet. This transfer is costly in time and manpower, and contributes to the cost of the goods.
What is needed is a pallet systems which facilitates this trend of reduced distribution cost and broadens the class of retailers who can take advantage of the new economies of distribution.
SUMMARY OF THE INVENTION
The modular pallet system of this invention has two or more pallets, each of which has four legs and which is capable of standing on its own as an independent unit. However, the pallets are formed to dimensions which are a fraction of conventional pallet sizes, such that one pallet alone serves as a quarter of a standard dimensioned pallet, while two pallets combined serve as a half of a standard dimensioned pallet. Each pallet has tabs and slots on the perimeter edges, with the result that two or more of the small pallets can be assembled into a standard size pallet. The pallets may be produced as single sheet thermoformed or twin sheet thermoformed parts, or could be injection molded or structural foam molded. The pallets are connected together in an interference fit and do not require any loose connectors or tools to assemble.
An adapter may be attached in a snap fit beneath four joined pallets to facilitate interaction between the combined pallets and conventional racks and conveyors, and to facilitate stacking.
It is an object of the present invention to provide a pallet which may be combined with other pallets to form a larger compound pallet which combines into a single unit load.
It is another object of the present invention to provide smaller pallets which may be connected together into standard size pallets without the use of tools.
It is an additional object of the present invention to provide a pallet of dimensions one quarter a standard pallet, which can be combined into a half-size or full size pallet with other identical pallets.
It is also an object of the present invention to provide a modular pallet which may be brought together with an adapter to allow use of the combined assembly with conventional racks and conveyors, and to permit stacking.
Further objects, features and advantages of the invention will be apparent from the following detailed description when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1
is an exploded isometric view of the pallet system of this invention having four pallets, load corners, and a pallet sleeve.
FIG. 2
is a fragmentary isometric view of the interior of a leg of the pallet of FIG.
1
.
FIG. 3
is a fragmentary isometric view of the exterior of a leg of a pallet of FIG.
1
.
FIG. 4
is a fragmentary top plan view of the pallet system of FIG.
1
.
FIG. 5
is a fragmentary cross-sectional view of the joined pallets of FIG.
4
.
FIG. 6
is a side elevational view of a plurality of pallets, with an individual pallet being dispensed onto a supporting surface.
FIG. 7
is a schematic isometric view of an alternative embodiment pallet system of this invention, having an adapter connected to four quadrant pallets to permit the combined pallets to better withstand the requirements of being racked, stacked or conveyed.
FIG. 8
is a fragmentary cross-sectional view of one leg of a pallet of
FIG. 7
being connected to the adapter.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring more particularly to
FIGS. 1-8
, wherein like numbers refer to similar parts, a pallet system
20
composed of a plurality of joined pallets
22
is shown in FIG.
1
. Each pallet
22
is of a size which is a regular fraction of a standard pallet size. For example, a standard 40 inch by 48 inch pallet may be assembled from four 20 inch by 24 inch pallets
22
. However, each pallet
22
is fully capable of standing alone as a freestanding, load supporting pallet.
As shown in
FIG. 4
, each pallet
22
has a rectangular horizontal deck
24
which engages and supports a load thereon. The deck has two adjacent first sides
26
, extending at a right angle to one another, and two adjacent second sides
28
which also extend at right angles to one another, with each first side
26
being parallel to one of the second sides, and perpendicular to the other of the second sides. Four identical pallet legs
30
are positioned at the corners
32
of the pallets
22
. The illustrated pallet
22
is formed in the single sheet thermoforming process from a sheet of thermoplastic material on a male mold. However, it should be noted that the pallet may be formed through other conventional plastic fabricating techniques, such as compression molding, twin sheet thermoforming, injection molding, or structural foam. In the single sheet thermoformed part, the center of the deck
24
is reinforced with a rigidifying structure
34
, such as the x-shape shown. Two parallel ribs
36
are formed adjacent the center segment
38
of the deck
24
on each of the second sides
28
. On the first sides
26
, a first uninterrupted rib
40
extends adjacent the center segment of the deck
24
, while a three-part rib
42
, is positioned outwardly and parallel to the first rib
40
.
The pallet
22
is releasably connected to another identical pallet
22
by structure positioned along the deck perimeter
44
. Each first side
26
has two downwardly protruding tabs
46
which engage with slots
48
formed in outwardly protruding ears
50
which extend from the pallets second sides
28
. As shown in
FIG. 2
, each tab
46
has a downwardly extending outwardly facing surface
52
. A groove
54
is formed in the outwardly facing surface
52
, for example by routing. As shown in
FIG. 5
, the tab
46
is narrowest where the groove
54
has been formed. The slot
48
in the protruding ear
50
is cut so that the narrow dimension of the slot is approximately the thickness of the tab
46
at the location of the groove
54
. Hence, when a loaded pallet
22
is positioned alongside another pallet and lowered on a forklift tine such that the tabs of the first pallet overlie the slots of the second pallet, the tabs will protrude into the slots
48
, and, once engaged, will connect the two pallets in an interference fit.
The tabs
46
may be formed in various fashions depending upon the plastic forming process employed. However, in a single sheet thermoforming process, the tab
46
may be formed over two protruding segments of the thermoforming mold which form two side by side pockets
56
, shown in
FIG. 2
, which causes the plastic to fuse sidewardly. The region adjacent the tab
46
is stiffened by an upwardly protruding cap
58
, which has a downwardly extending ramp
60
adjacent the pockets
56
, to reduce the draw into the pockets. The ears
50
protrude outwardly from the second sides
28
and have a downwardly protruding flange
62
which contributes to the stiffness of the ear and the slot opening.
As shown in
FIG. 5
, a valley
64
is defined between the deck center segment
38
and the ribs
36
or
40
. The depth of the valley
64
defines the thickness of the deck
24
. It will be noted that the ears
50
extend at a position which is spaced halfway between the uppernost surface of the deck and the lowermost surface of the valley
64
.
As shown in
FIG. 6
, the pallets
22
are adapted for automated dispensing from a stack
66
. The automated pallet dispenser
68
has two sets of retractable tines, a lower set
70
which engages the lowermost pallet
22
which is about to be dispensed, and an upper set
72
of tines which engages the remainder of the stack
66
. In operation, both sets
70
,
72
of tines are inserted beneath the decks
24
of the lowermost pallet and the pallet directly above. The lower set
70
of tines is spaced above a support surface
74
which may be a floor or a moving conveyor belt. The lower set
70
is spaced from the support surface
74
a distance slightly greater than the height of a pallet
22
. When the lower set of tines
70
are retracted, the lowermost pallet is no longer supported and it falls to the underlying support surface
74
. The dispensed pallet
76
may then be removed by a forklift truck, or carried away on a conveyor belt for loading. After the pallet
76
has been dispensed, the lower set of tines
70
are inserted, and the upper set
72
of tines is retracted, allowing the entire stack
66
to descend onto the lower set of tines
70
. In this way the entire stack of pallets
22
may be dispensed until it is time to replenish the stack.
Because of the automated nature of the machine dispensing of the pallets, it is important that each pallet be spaced a uniform distance from the overlying pallets within a stack, and that nested pallets do not wedge themselves together. To ensure these properties in the pallets
22
, the legs
30
are formed with negative draft structure, as shown in FIG.
2
and FIG.
5
.
As shown in
FIG. 3
, each leg
30
has a first side wall
78
which extends at a right angle to a second side wall
80
on the exterior of the pallet
22
. Each side wall
78
,
80
, has an upwardly opening channel
82
. The channels
82
have a lower surface
84
which defines the upper limit of a leg segment
86
. The lower surface
84
is positioned at approximately the level of the underside of the deck, as shown in FIG.
6
. The leg segment
86
extends downwardly and outwardly from the lower surface
84
of the channel
82
, and terminates in an inwardly extending lower floor segment
88
. The lower floor segment
88
, because it protrudes from the channel
82
, will extend across the channel lower surface
84
of an underlying pallet
22
. Furthermore, the two channels
82
in the perpendicular sidewalls
78
,
80
serve to locate the two overlying pallets
22
with respect to one another. Furthermore, the lower surfaces
84
of the channels
82
positively limit the extent to which overlying pallets may nest. The two lower floor segments
88
form parts of the leg floor
90
, as shown in
FIGS. 3 and 4
.
As shown in
FIG. 1
, the pallets
22
are provided with structure which permits them to readily receive reinforcing corner stiffeners
92
or a protective pallet sleeve
94
. In forming a palletized load, it is common to place the supported articles on the pallet deck
24
, position right angle paperboard or plastic stiffeners
92
at the corners, and then shrinkwrap the entire pallet, stiffeners, and product assembly. Each leg
30
of the pallet
22
has a step
96
, best shown in
FIG. 3
, located between the first side wall and the second side wall
78
,
80
at the leg exterior. The step
96
has an upwardly extending projection
98
which defines a right angle groove
100
with the leg walls
78
,
80
to receive and position a stiffener
92
. In situations in which each pallet will be loaded with goods for later breaking down into separate groups, each pallet may be individually shrink-wrapped before being connected together to adjoining pallets. In such a situation, stiffeners may be provided in each pallet leg.
A pallet sleeve groove
102
is defined between the exterior rib
36
and exterior upstanding flange
120
. Downwardly opening slots
122
may be cut in the sleeve where it bridges two connected pallets
22
. This groove
102
is positioned to be aligned with the channels
82
in the legs, such that the sleeve will extend across the two connected legs where two pallets
22
are joined. The sleeve may constitute a point of purchase merchandise display in the retail environment.
The pallet system
20
, comprised of several connected pallets
22
and related corner stiffeners or sleeve, may then be transported and stored as needed as a single unit. At the point at which the loads are to be broken down, the overall shrinkwrapping may be removed, leaving individual loads on the still connected pallets
22
. The tabs which extend into the slots of adjoining pallets
22
securely connect the pallets without the need for additional fasteners or connectors. However, the individual pallets are readily separated by inserting the tines of a forklift truck beneath only that pallet or pallets which is to be separated, and lifting upwardly. The weight of the non engaged pallets
22
is sufficient to overcome the interference fit between the pallets, allowing them to be readily separated. The spacing of the four pallet legs
30
is such as to permit a single tine of a forklift truck to be received between the legs. Because conventional forklift truck tines are fairly wide with respect to the dimensions of the pallet
22
, it is possible to support a load on a single tine. Moreover, the individual pallets
22
may be engaged and supported on properly configured hand trucks.
As shown in
FIGS. 7-8
, an alternative embodiment pallet system
104
provides a stiff unitary adapter
106
which engages beneath four connected pallets
108
, similar to the pallets
22
discussed above, but having holes
110
in the leg
112
floors
114
which engage with barbs or protrusions
116
extending upwardly from the adapter
106
. The adapter has the dimensions of a standard size pallet, and has a smooth undersurface which makes it suitable for transport on conventional conveyor systems. Furthermore, the adapter
106
is preferably sufficiently stiff to allow the combination of four pallets
108
and their loads to be supported on conventional rack systems designed for wood pallets. In addition, the adapter
106
provides additional linkage between the connected pallets
108
to facilitate stacking of multiple loaded pallet assemblies. The adapter may have interior cutouts
118
to permit the pallet system
104
to be conveyed on a conventional hand truck. The adapter
106
may be constructed of vessel, plastic composites or a combination of these materials.
It should be noted that although a single sheet thermoformed structure has been described above, alternative structures fabricated through different plastic processes may be employed. For example, alternative structures for insuring the limited nesting of the pallets may be formed in molding processes such as compression molding, which do not require that part walls being of generally constant thickness. For example, the side walls of each leg may be provided with interior ledges at a specified height to prevent over nesting of the stacked pallets. Or, the lower level of the pallet legs may be filled with webbing or cross stiffeners which serve to prevent over nesting. In addition, the tab structure may be formed in many different fashions to provide the interference fit with the slot on an adjoining pallet. For example, in a compression molded part, the pallet tabs could be provided with a barb at its lowest extend, which protrudes sidewardly beneath the slot when engaged with the slot.
It is understood that the invention is not limited to the particular construction and arrangement of parts herein illustrated and described, but embraces such modified forms thereof as come within the scope of the following claims.
Claims
- 1. A pallet system comprised of a plurality of pallets, each pallet comprising:an upwardly facing deck defining an exterior perimeter of the pallet, the deck being rectangular and having two adjacent first sides, and two adjacent second sides which are perpendicular to the first sides, wherein the deck has four corners; a leg which extends downwardly from each deck corner, wherein each leg has an upwardly extending side wall, with portions of said leg side wall defining an upwardly opening channel, and portions of each leg positioned below the leg channel to extend generally perpendicular to and inwardly from said side wall to engage the channel of an underlying like pallet and restrict over nesting of two stacked pallets; at least one tab which extends downwardly from each first side of the deck; at least one ear which extends outwardly from each second side of the deck, wherein portions of the ear define a slot which is dimensioned to receive a tab in an interference fit, such that said plurality of pallets are combinable into a single larger pallet.
- 2. The pallet system of claim 1 wherein each pallet leg has a first side wall which is approximately perpendicular to a second side wall, and wherein the first side wall has a first upwardly opening channel, and the second side wall has a second upwardly opening channel, and wherein portions of the first side wall extend downwardly and outwardly from the first channel to define a first leg segment which terminates in a lower floor segment, and wherein portions of the second side wall extend downwardly and outwardly from the second channel to define a second leg segment which terminates in a lower floor segment, such that when a first pallet is supported on a second pallet the floor segments overlie the first channel and the second channel.
- 3. The pallet system of claim 1 further comprising a rigid adapter positioned beneath the plurality of pallets, and extending between all said plurality of pallets to support them.
- 4. The pallet system of claim 3 further comprising portions of the adapter which extend into engagement with the plurality of pallets in a snap fit.
- 5. A machine dispensable pallet comprising:a rectangular deck having an upper surface and four corners; four legs extending downwardly from the rectangular deck, each leg positioned at one of said corners, wherein each leg has two outwardly facing leg side walls, and wherein at least one of the leg side walls has portions which project outwardly as the portions extend downwardly from the deck, wherein said at least one leg side wall has portions defining an upwardly opening channel which extends from an uppermost portion of said at least one leg side wall downwardly toward said projecting portions, said channel being aligned above said projecting portions and sized to receive and support the projecting portions from a second like pallet.
- 6. The pallet of claim 5 wherein the pallet deck defines an exterior perimeter of the pallet, the rectangular deck having two adjacent first sides, each first side having at least one tab which extends downwardly from each first side; and each second side having at least one ear which extends outwardly from each second side of the deck, wherein portions of the ear define a slot which is dimensioned to receive a tab similar in dimension to the at least one tab in an interference fit.
- 7. The pallet of claim 5 further comprising a plurality of substantially identical pallets stacked one upon another.
- 8. The pallet of claim 5 further comprising three substantially identical pallets abutted together to form a single larger rectangular pallet co-joined with the pallet to form the single larger pallet by mechanical interlocks between abutting pallets.
- 9. A pallet assembly comprising:two identical pallets removably connected together, wherein each pallet comprises: a rectangular deck having an upper surface and four corners; four legs extending downwardly from the rectangular deck, each leg positioned at one of said corners, openings being defined between each pair of two legs; a plurality of tabs which are positioned above the openings on a first side of the pallet, and which extend downwardly; a plurality of slots positioned above the openings on a second side of the pallet, wherein the two identical pallets are securely connected by engagement of the tabs on one pallet extending downwardly into the slots of the other pallet, the individual pallets being readily separated by inserting the tines of a forklift truck beneath only that pallet which is to be separated, and lifting upwardly, the weight of the non engaged pallets being sufficient to overcome the fit between the pallets, allowing them to be readily separated.
- 10. A pallet assembly comprising:a first pallet, a second pallet, a third pallet, and a fourth pallet, wherein each pallet has a deck and legs which extend downwardly from the deck, each pallet having portions which extend sidewardly to mechanically engage with an adjoining pallet, and wherein portions of each pallet leg define a downwardly opening hole; and a stiff unitary adapter positioned beneath the pallets, the rigid adapter having a plurality of upwardly extending barbs, one of said barbs extending into each of said pallet leg holes, to thereby engage the four pallets to the adapter in a snap fit.
- 11. The pallet assembly of claim 10 wherein portions of the adapter define a plurality of interior cutouts to permit the pallet assembly to be conveyed on a convention hand truck.
US Referenced Citations (30)