Note: Descriptions are shown in the official language in which they were submitted.
CA 02790885 2012-08-22
WO 2011/109715 PCT/US2011/027203
FOUR-WAY STACK-AND-NEST PALLET
WITH FULL WINDOW-FRAMED RUNNERS
BACKGROUND OF THE INVENTION
This invention relates generally to goods-supporting pallets like the kind
transported, raised and lowered by forklift trucks. More specifically, the
invention relates to
goods-supporting pallets that are made of environmental-friendly plastics and
nest one into
the other to reduce or minimize storage space.
Goods-supporting pallets made of wood and plastic are well-known in the art.
One
of the advantages of plastic pallets over wooden pallets is that plastic
pallets can be
designed to nest one within the other. However, prior art plastic nesting
pallets do not
provide a runner design which accommodates 4-way entry of the forklift, nor do
they
provide full window-frame and same-dimensioned runners. Additionally, those
plastic
nesting pallets are usually one-piece designs which do not incorporate runners
of any kind.
Plastic pallets that do have runners are usually assembled from different
molded parts and
cannot nest.
The pallet disclosed and claimed herein incorporates the best safety, economic
and
manufacturing features of two distinct types of pallets. Pallets with runners
(either wood or
plastic) offer fork truck safety, pallet conveyablity, and pallet double-
stacking. Pallets
without runners (usually only plastic) offer economic outbound and return
shipping and
make efficient use of warehouse space. However, there are times when the
qualities of both
types of pallets are desirable in the same pallet. The claimed invention
incorporates two
critical features of each type of pallet, full window frame runners for safety
and full nesting
capacity for economic shipment, in the same pallet. No other pallet is
available with these
combined critical features.
CA 02790885 2012-08-22
WO 2011/109715 PCT/US2011/027203
2
Because of significant technical challenges, no prior art pallet design
incorporates all
of the features of the pallet made according to this invention. Prior art
pallet designs have
either compromised on the full window frame runner system, thereby reducing
the safety
factor, or have limited the nesting ratio, thereby reducing the economic
return of the nesting
pallet. To the inventors' knowledge, there is no prior art pallet design that
marries both the
full window frame and full nesting in the same pallet. A pallet design that
accomplishes
both is difficult to achieve given that the design has to maintain industry
standards to
survive the rigors and abuse of the fork-truck world yet still accommodate an
industry load
requirement.
CA 02790885 2012-08-22
WO 2011/109715 PCT/US2011/027203
3
SUMMARY OF THE INVENTION
A pallet made according to this invention has a deck that provides a goods-
supporting surface along with a plurality of recessed portions that form
angled leg portions
below the lower surface of the deck. In a preferred embodiment, the angle or
draft of
sidewalls of the recess is about 4 from vertical. The pallet also includes a
first and second
plurality of full window-framed runners, the first plurality of window-framed
runners being
arranged perpendicular to the second plurality of window-framed runners in
order to
accommodate 4-way entry for a forklift truck. Each window-framed runner shares
an
angled sidewall of each of the two adjacent recessed portions that it is
located between. The
runners are also offset from the peripheral edge of the pallet.
The plurality of recessed portions includes a centrally located recessed
portion,
recessed portions located toward a peripheral edge of the pallet, and recessed
portions
located at the corners of the pallet. Each edge or side recessed shares a
common centerline
with the central recessed portion. The goods supporting surface may be a solid
surface
having a plurality of ribs on its lower surface. The runners may also include
ribs.
To accommodate the floor runner portion of a second pallet and help provide an
interlocking design, the deck includes a plurality of channels. Each channel
is located
above a floor runner portion of an opposing window-framed runner and sized to
receive a
window-framed runner of the second pallet. Each recessed portion also includes
a stop to
arrest the downward travel of the foot portion of the second pallet so that
about half the
height of the second pallet nests within the first pallet.
Objects of the invention are to provide a plastic nesting pallet that has (1)
a one-
piece design; (2) full window-frame runners (stringers) to improve safety
during transport
and stacking; (3) a runner design that improves pallet storage at least about
50%; (4)
runners which are off-set and chamfered to protect the feet; (5) runners with
a common
CA 02790885 2012-08-22
WO 2011/109715 PCT/US2011/027203
4
dimension; (6) a top deck that incorporates the runners but still allows the
pallet to nest; (7)
a foot design that provides an inter-locking footprint but allows for de-
stacking; and (8)
more static and dynamic load carrying capacity than a similarly sized wooden
pallet yet is at
least one-third the weight of that pallet.
CA 02790885 2012-08-22
WO 2011/109715 PCT/US2011/027203
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top view of a preferred embodiment of a pallet made according to
this
invention.
FIG. 2 is an elevation front view of the pallet of FIG. 1.
5 FIG. 3 is a cross-section view of the pallet of FIG. 1 taken along section
line 3-3.
FIG. 4 is an elevation right-side view of the pallet of FIG. 1, the left-side
being a
mirror image.
FIG. 5 is a bottom view of the pallet of FIG. 1
FIG. 6 is an isometric view of the pallet of FIG. 1.
FIG. 7 is an isometric bottom view of the pallet of FIG. 1.
FIG. 8 is a cross-section view of the pallet of FIG. 1 as it nests within
other pallets.
FIG. 9 is a partial bottom view of another preferred embodiment of a pallet
made
according to this invention.
CA 02790885 2012-08-22
WO 2011/109715 PCT/US2011/027203
6
Elements. The following elements are illustrated in the drawings and
referenced in
the Detailed Description of the Preferred Embodiments
Stack-and-nest pallet 120 Lower surface of 20
11 First pallet side 121 Cross-patterned rib
5 13 Centerline 130 Runner
Second pallet side 131 Floor runner portion
17 Centerline 133 Supporting leg portion
19 Fork entry/window 135 Upper end of 133
Deck 137 Rib
10 21 Goods supporting surface 139 Bottom end of 131
23 Trapezoidal-shaped portion of 21 141 Lower edge of 137
Rectangular-shaped portion of 21 143 Lower end of 133
27 Goods supporting surface 145 Cross-patterned rib
29 Goods supporting surface 150 Channel-shaped rib
15 30 Open channel 151 Bottom end
31 Longitudinal side 160 Leg or foot
50 Channel 163 Petal portion
60 Recess 165 Sidewall
61 Central portion 169 Bottom end
20 63 Satellite or petal portion 171 Hole
65 Sidewall 173 Stop
67 Top end 175 Upper end of 173
CA 02790885 2012-08-22
WO 2011/109715 PCT/US2011/027203
7
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A pallet made according to this invention represents a new concept in plastic
runner-
ed pallets. The pallet (1) blends traditional pallet safety with economic re-
use; (2) lowers
costs and eliminates assembly because of its one-piece design; (3)
incorporates geometry
that protects its internal structure; (4) provides integrated full window-
frame runners and 4-
way entry; (5) lowers handling costs by providing full 2-to-1 nesting; (5) is
compatible with
all conveyor systems; (6) double stacks with about 8% greater runner surface
area (meaning
the pallet stacks with greater bottom surface area than prior art pallets);
(7) is about 50%
lighter than a comparable-sized wood pallet; (8) is 100% recoverable and
reusable; (9) has a
carbon footprint about 40% smaller than prior art wood pallets; and (10)
accommodates
industry load requirements. For example, a pallet made according to this
invention that is
made of recycled resin and measures 48 inches long (121.92 cm); 40 inches wide
(101.6
cm), and 5-1/2 inches (13.97 cm) tall weighs 27 pounds (12.25 kg), can be
stacked 42 high
in a 97-inch (246.38 cm) column, has a dynamic load capacity of 2,400 pounds
(1088.62
kg), and has a static load capacity of 7,500 pounds (3401.94 kg) (not edge
rack-able).
Because of its improved nesting, 1,260 units can fit within a standard 53-foot
(16.15 m)
truck making return economically more attractive.
Referring to the drawings and first to FIGS. 1, 6 & 8, a preferred embodiment
of a
stack-and-nest pallet 10 made according to this invention has a deck 20 that
incorporates
built-in runners (stringers) 130 in a full window frame design but allows a
second pallet 10
to nest inside the first pallet 10 up to a 2.5 to 1 ratio. Deck 20 includes
channels 30 and
recesses 60 that receive the legs 160 and runners 130 of the second pallet 10,
respectively.
The two pallets 10 preferably nest so that the total height of the nested
arrangement is
substantially the same height "X" as a single pallet 10 (see FIG. 8). A pallet
10 made
according to this invention is about 33% lighter than a comparably sized wood
pallet while
CA 02790885 2012-08-22
WO 2011/109715 PCT/US2011/027203
8
at the same time improving pallet storage by up to about 60%. In a preferred
embodiment,
pallet 10 is about 48" (121.92 cm) x 40" (101.6 cm) x 5.5" (13.97 cm), made
from
environmentally friendly plastic material, and weighs about 27 pounds (11.34
kg).
Referring now to FIGS. 5-7, each leg 160 conforms to and extends below a
respective recess 60, which forms the hollow interior portion of the leg 160.
The legs 160
and recesses 60 have a unique-interlocking footprint (described below) that is
designed to
allow for de-stacking the nested pallets 10. The legs 160 and recesses 60 are
one of three
types: center C, corner K, or side S. When viewing pallet 10 from above its
deck 20, each
recess 60 has a substantially square- or rectangular-shaped central portion 61
and a set of
square- or rectangular-shaped foot or petal portions 63, each petal portion 63
being located
at a corner of central portion 61. Recesses 60C & s have four petal portions
63(1_(4). Recess
60K has three petal portions 63K(1)-(3).
The sidewalls 165 of the each leg 160 merge with the sidewalls 65 that form
the
recess 60 and extend below the lower surface 120 of deck 20 (see FIGS. 3 & 8).
Therefore,
each leg 160 has a central portion 161 and petal portions 163 that correspond
to those of its
complementary recess 60. The sidewalls 65, 165 taper at a same draft angle a
from the top
end 67 of recess 60 toward the bottom end 169 of leg 160. In a preferred
embodiment, draft
angle a is about 4 and sidewalls 165 are about 0.15" (0.38 cm)thick. Bottom
end 169
includes a hole 171.
Preferably, one of three different sized rectangular-shaped open channels 30
lies
between adjacent recesses 60c & K; 60C & s; and 60K & s (see also FIG. 1).
Channel 30N is the
narrowest channel 30 and runs parallel to pallet side 11 (which is preferably
the shorter side
of pallet 10), between the center recess 60c and a corner recess 60K. Channel
30w, which is
the widest channel 30, also runs parallel to pallet side 11 but between center
recess 60C and
a side recess 60s. Channel30N1-whose width lies between that of channels 30N &
w-runs
CA 02790885 2012-08-22
WO 2011/109715 PCT/US2011/027203
9
substantially parallel to pallet side 15 (the longer side of pallet 10),
between a corner recess
60K and a side recess 160s.
A runner 130 lies substantially directly below each channel 30. Each runner
130 is a
full window frame runner and provides a fork entry 19 (making pallet 10 a full
four-way
entry pallet). Runner 130 is chamfered and includes a floor runner portion 131
and a
supporting leg portion 133. The leg portion 133 is off-set relative to the
floor runner
portion 131 and extends away from an opposing leg 160 at a draft angle P. In a
preferred
embodiment, draft angle (3 is about 4 , substantially equal to that of draft
angle a.
Similar to channels 30, each floor runner portion 131 is one of three
different
widths, with floor runner 131w corresponding to, lying beneath, and having a
slightly
smaller width than channel 30w so that the runner 130,E of one pallet 10 may
be received by
a corresponding channel 30,,, of a second pallet 10. Floor runner portion 131N
corresponds
to, lies beneath, and has a slightly smaller width than channel 30N. Floor
runner portion
131M corresponds to, lies beneath, and has a slightly smaller width than
channel 30M. In a
preferred embodiment, floor runner 131N is about 1.4" wide (3.55 cm) , 131M is
about 1.9"
(4.83 cm) wide, and 131w is about 2.9" (7.37 cm) wide. The leg portion 133 at
wider at its
upper end 135 than at its lower end 145 (which merges into floor runner
portion 131).
The bottom end 139 of the floor runner portion 131 lies substantially in the
same
horizontal plane as the bottom end 169 of the legs 160. Extending between the
upper end
135 of the leg portion 133 are ribs 137. Each rib 137 lies substantially
directly below a
longitudinal edge 31 of a corresponding channel 30. The rib 137 runs the
length of the
channel 30 and extends downward and beyond the lower surface 120 of deck 20.
Deck surface 20 may include a channel 50 that corresponds to a channel-shaped
rib
150 (see FIGS. 1 & 5). Channel 50 runs diagonally between and in communication
with
opposing petal portions 63 of the center recess/leg 60c/160c, and an adjacent
corner
CA 02790885 2012-08-22
WO 2011/109715 PCT/US2011/027203
recess/leg 60K/160K. The rib 150 extends past the lower surface 120 of deck 20
with its
bottom end 151 lying substantially in the same horizontal plane as the lower
edge 141 of the
rib 137. FIG. 9 illustrates an alternate preferred embodiment of pallet 10.
Channel 50 and
its corresponding rib 150 have been eliminated in favor of a cross-patterned
rib design 121
5 on the lower surface 120 of deck 20. Cross-patterned ribs 145 have also been
added to the
floor runner portion 131.
The arrangement of open channels 30, channels 50, and recesses 60 define
different
goods supporting surface portions of deck 20. Referring to FIG. 6 and dividing
pallet 10
into four quadrants I-IV as defined by centerlines 13 & 17, and using quadrant
I as an
10 example, two goods supporting surfaces 21A & B lie opposite one another and
adjacent to
channel 50. Each surface 21 is made up of a trapezoidal-shaped portion 23 and
a
rectangular-shaped portion 25. Trapezoidal-shaped portions 23A & B are located
between
channels 30M and 50. Rectangular-shaped portions 25A & B are located adjacent
channels
30w and 30M, respectively. Another goods supporting surface 27A & B lies
between
channel 30M and pallet side 15 and between channel 30N and side 11,
respectively. Goods
supporting surface 29 lies between the channels 30 and recesses 60.
Referring to FIGS. 2-4 & 8 (see also FIG. 9), the bottom end 169 of each leg
160
rests on a floor surface or, when nesting on a second pallet 10, on the
respective upper end
175 of a set of stops 173 located within each recess 60 of the second pallet
10 (see also FIG.
1). The bottom end 139 of each runner 130 rests on the floor surface or, when
nesting on a
second pallet, is received by the open channel 30 of the second pallet.
Therefore, when
pallets 10 are nested, each recess 60 of the lower pallet 10 receives a
portion of the
complementary leg 160 of the upper pallet 10 and each channel 30 of the lower
pallet 10
receives a runner 130 of the upper pallet 10. The stops 73 are preferably
dimensioned so
that when the upper pallet 10 is nesting within the lower pallet 10, the
portion of the upper
CA 02790885 2012-08-22
WO 2011/109715 PCT/US2011/027203
11
pallet 10 residing within the lower pallet 10 is about one-half the total
height of each pallet
or "X/2" and the clearance between the leg 160 and its receiving recess 60 is
about 0.05"
(0.127 cm).
A pallet made according to this invention blends concepts, materials, features
5 without compromise to meet the objectives previously stated. Further, it
accomplishes the
objectives in a one-piece design. Almost all other prior art runner-ed plastic
pallets require
two (or more) parts that are post-forming assembled. The inventors' pallet has
been
designed and engineered for production on a simple straight pull mold (without
cams) that
lowers production time and dollars. One critical technical issue was pallet
runner survival
10 when stacks of pallets (e.g. 40 pallets stacked one on top of the other)
are moved at one
time. The runner has been reinforced to withstand that function, something
most similar
pallets have not done.
While preferred embodiments of a stack-and-nest pallet have been described
with a
certain degree of particularity, modifications can be made in the details of
construction
without departing from the scope of the patent claims below.
