Note: Descriptions are shown in the official language in which they were submitted.
CA 02207281 2005-07-07
1
PLASTIC PALLET ASSEMBLY
DESCRIPTION
Technical Field
The present invention relates to pallets for storing
and transporting goods, and more particularly to a pallet
comprising a base and a deck connected by a plurality of
__
CA 02207281 2005-07-07
2
The pallet can be easily assembled for supporting goods
r,a ~....;,.. ~;..-,~r,~..,i.,,~,a ~.,~.. +-r..r~r..,~~-,~;...-, ".-,~a
~..~..Y~,.~
a
CA 02207281 1997-06-06
WO 96/17783 PCT/US95115896
3
B_ackaround Of The Invention
It is customary to transport goods and to store
goods on pallets. Palletized goods are maintained in a
position above the flooring which can be very
advantageous in areas where there is flooding or where
the condition of the flooring is either rough or of
concern. Standard pallets are particularly useful in
materials handling because forklift equipment can
maneuver the pallets by inserting their forklift tines
into channels provided by the pallet. Typically, pallets
are constructed of wood. In the past, wooden pallets
have provided advantages of economy, simplicity and
durability, principally because of the lack of other
suitable materials. However, wooden pallets are
extremely heavy and require costly hand labor in their
fabrication.
In the past decades, disposable pallets have been
proposed and, with the growth of the plastics industry,
a wide variety of plastics have been investigated to
determine their suitability for use in producing pallets.
Plastic pallets can easily be molded and are stronger and
lighter in weight than wooden pallets; also, they can now
be made with recyclable materials. Furthermore, plastic
pallets are more durable than wooden pallets. Recent
plastic pallets that are light in weight, durable,
capable of supporting heavy loads, easy to manufacture
and have a minimum number of interchangeable parts are
disclosed in Serial No. 29/024,050, filed June 7, 1994
for a PLASTIC PALLET ASSEMBLY, U.S. Patent No. DES
347,511 for a TWO-PART INTERLOCKING PLASTIC PALLET, U.S.
Patent No. DES 346,681 for a TWO PART INTERLOCKING
PLASTIC PALLET, U.S. Patent No. 5,343,814 for a PLASTIC
PALLET ASSEMBLY, U.S. Patent No. 5,197,395 for a PLASTIC
PALLET WITH DECK ASSEMBLY, and U.S. Patent No. 4,843,976
' 35 for a PLASTIC PALLET. The pallets and connectors
disclosed in these patents and Applications have been
highly successful. In an effort to improve thereon, to
reduce the cost and weight of the pallets and to increase
strength yet not decrease durability, the pallet of the
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
4
present invention was developed. The present pallet is
useful in material handling and designed for use with
forklift equipment.
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
gua~ary Of The Invention
According to a first aspect of the present
invention, a pallet base, a pallet deck, a plurality of
separate connectors, and a plurality of internal,
5 integral connectors is disclosed. The pallet base has an
inner surface and an outer surface, a pair of
substantially parallel side members and a pair of
substantially parallel end members that are substantially
perpendicular to the side members, a first cross member
disposed between and connected to the end members, and
two second cross members disposed between and connected
to the side members. The inner surface has a plurality
of spaced apart transverse inner ribs projecting
therefrom and the opposed outer surface has a plurality
of spaced apart transverse outer ribs projecting
therefrom. The side members, the end members and the
cross members are generally U-shaped in cross-section.
Specifically, the side members, the end members and
the cross members of the pallet base include a
substantially horizontal second portion having two sides
with a ramp portion and a substantially horizontal first
portion integral with each of the two sides of the
horizontal second portion, the outer surface of the ramp
portions and the horizontal second portion being concave .
The pallet base further includes a plurality of openings
therein for receiving the separate connectors and the
integral, internal connectors for cooperating with the
connected pallet deck.
According to a second aspect of the present
invention, a generally rectangular pallet deck is
disclosed that has a first side, an opposed second side,
a first end and an opposed second end and is also
interconnected to the pallet base by the separate
connectors. The deck further includes a substantially
° 35 planar outer surface with perimeter reinforcement means,
an inner surface with a reinforcement structure
projecting outwardly therefrom, openings for receiving
the separate connectors, and a plurality of integral,
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
6
internal connectors for cooperating and mating with the
pallet deck.
According to a further aspect of the present
invention, internal connectors are disclosed having a
first element integral with the inner surface of the base
cooperating with a second element integral with the inner
surface of the deck. These internal connectors are used
in addition to the four separate connectors. Each
separate connector is at a corner of the pallet and
disposed between the base and the deck and further
cooperates with openings in each of the deck and the
base. As to the integral internal connectors, the first
element includes a central core with projections thereon
and the second element includes a sleeve with inwardly
projecting spokes and an internal, central receiving core
having an opening at the distal end thereof adapted to
receive the central core of the first element and means
for receiving and seating the projections of the first
element . The proj ections of the first element are formed
by circumferentially spaced slots extending from the
distal end of the first element which produce a set of
tangs and each tang has a barb formed adjacent the distal
end thereof and the receiving core of the second element
has an opening at the distal end thereof to receive the
central core with tangs. In addition, each barb has a
flat lower surface which extends perpendicular to the
axis of the core and has a tapered outer surface
extending from the outer edge to define a ramp.
According to still a further aspect of the present
invention, the second element further includes, at
opposed sides on the sleeve, a projecting post with a
barb thereon for cooperating with the first element.
According to yet another aspect of the present
invention, the separate connectors include a central
hollow core member having slots extending from opposite
ends to produce a plurality of flexible tangs at opposite
ends of the core member, a plurality of radial spokes
extending from the periphery of the core'member between
the tangs, a non-circular sleeve surrounding the core
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
7
member and being integral with outer ends of the spokes,
and an inwardly-directed integral force-absorbing
flange between the tangs. The sleeve is rectangular and
the radially spaced spokes are spaced approximately 30 to
60 degrees apart; they are spaced at 45, 35 and 55
degrees from one another. A plurality of transverse
spokes are integral with at least two radial spokes for
added stability and strength. Moreover, the hollow core
member is circular and the slots terminate in close
proximity to planes defined by the spokes. As with the
internal connectors, each of the tangs has a barb formed
adjacent a free edge thereof and each barb has a lower
flat edge extending perpendicular to the axis of the
hollow core member . Finally, the tang spans approximately
ninety degrees, the tangs at each opposed end are
circumferentially offset from the tangs at the other
opposed end.
CA 02207281 1997-06-06
WO 96/17783
PCT/US95/15896
8
Brief Description Of The Drawings
Figure 1 is a perspective top view of the plastic
pallet comprising a deck, a base and a plurality of
connectors made in accordance with the teachings of the
present invention;
Figure 2 is a first end elevation view of the pallet
of Figure 1, the second, opposed end elevation view being
a mirror image thereof;
Figure 3 is a first side elevation view of the
pallet of Figures 1 and 2, the second, opposed side
elevation view being a mirror image thereof;
Figure 4 is a bottom plan view of the base of the
pallet of Figures 1 - 3;
Figure 5 is a top plan view of the base of the
pallet of Figures 1 - 4 with the deck removed along line
5-5 in Figure 1;
Figure 6 is a top plan view of the deck of the
pallet of Figures 1 - 5;
Figure 7 is a bottom plan view of the deck of the
pallet of Figures 1 - 6 with the base removed along line
7-7 in Figure l;
Figure 8 is a cross-sectional view along line 8-8 in
Figure 1;
Figure 9 is a cross-sectional view along line 9-9 in
Figure 7;
Figure 9A is a cross-sectional view of alternative
construction to that shown along line 9-9 in Figure 7;
Figure 10 is a cross-sectional view along line 10-10
in Figure 5;
Figure 11 is a perspective top view of a separate
connector for use with the pallet of Figures 1 - 10;
Figure 11A is a perspective top view of an
alternative separate connector for use with the pallet of
Figures 1 - 10;
Figure 12 is a top plan view of the connector of
Figure 11;
Figure 13 is a bottom plan view of the connector of
Figures 11 - 12;
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
9
Figure 14 is a right elevation view of the connector
of Figures 11 - 13, the left elevation view being a
mirror image thereof;
Figure 15 is a front elevation view of the connector
of Figures 11 - 14, the rear elevation view being a
mirror image thereof.
Figure 16 is a top plan detailed view of the
integral internal connector of the base;
Figure 17 is a cross-sectional view of the integral
internal connector of Figure 16;
Figure 18 is a bottom plan detailed view of the
integral internal connector of the deck; and,
Figure 19 is a cross-sectional view of the integral
internal connector along line 19-19 of Figure 18; and,
Figure 20 is a cross-sectional view of the integral
internal connector of along line 20-20 in Figure 7.
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
Detailed Description Of The Preferred Embodiment
While this invention is susceptible of embodiment in
many different forms, there is shown in the drawings and
will herein be described in detail a preferred embodiment
5 of the invention with the understanding that the present
disclosure is to be considered as an exemplification of
the principles of the invention and is not intended to
limit the broad aspect of the invention to the
embodiments illustrated.
10 A. The Pallet Assembly
Figures 1 - 3 of the drawings show a plastic pallet,
generally designated by reference numeral 10, having
three primary components. The components are a base 20,
a deck 100 and a plurality of connectors 11. The
connectors 11, interconnecting the deck and base, are
specially designed so the pallet can be assembled without
the need for specially designed tools, and the connectors
can be snap-fitted onto the deck and base.
In the preferred embodiment, the pallet incorporates
six (6) separate connectors 11 and six (6) integral
connectors lla. Both the deck and the base have openings
which define surrounding abutments recessed below the
exposed surface and the connectors (separate and
integral) have flexible tangs with barbs which engage the
abutments. The pallet 10 has opposed sides 13 and
opposed ends 14. In the illustrated embodiment, the
separate connectors 11 are shown positioned at the four
corners of the base and deck members and midway along
each opposed end 14. Integral connectors or connection
means lla are built into the base and deck of the pallet
along the sides 13 between the corners and in internal
rows parallel to the ends 14. The connectors ll,lla are
positioned so forklift tines can be inserted into side
channels 15 and end channels 16 for lifting and moving
the assembled pallet and the palletized goods. The six
separate connectors are positioned where, it has been
found, there are the highest probabilities of potential
damage. Specifically, misdirected loads fall upon or
misaligned forklift contact the corner areas most
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
11
frequently. Thus, broken connectors located in these
areas can be easily removed and replaced.
The six separate connectors are positioned with one
in each corner and one between the corners, on the short
side, here the ends 125,126 of the pallet. The integral
connectors are placed along the long side, here the sides
123,124 of the pallet, to allow a longer side. The extra
internal supports permit the overall size of the pallet
to be larger than prior pallets. They reduce the
distance between connectors, minimizing "bowing" due to
the weight of the load being supported.
Finally, the channels 15,16 are unobstructed within
the pallet . The connectors 11, lla are oriented and sized
so that the forklift tines can be inserted into either
side or end and pass, without obstruction, through the
pallet. See Figure 7, wherein the orientation of the
connectors is shown and the distances, designated X and
Y, for the channels 15,16 is shown.
B. The Base
The base 20 of the present invention, shown in
detail in Figures 4, 5, 8 and 10, is used below the deck
100 and while in use generally rests on the ground or
floor. Because goods are not normally placed directly on
the base 20, it is not a flat, continuous surface,
rather it is much like a frame structure. The base
supports the deck above the flooring. The base has two
surfaces, namely an inner surface 21 (Figure 5) and an
outer surface 22 (Figure 4). The outer surface 22 is the
surface that faces out from the pallet; the surface that
faces down and contacts the ground or floor when the
pallet is constructed. The inner surface 21 is the
surface facing the inside of the pallet, i.e., the
surface the connectors are attached to and the surface
facing the deck.
The base 20 is generally rectangular in shape. It
has a first side 23, an opposed second side 24, a first
end 25 and an opposed second end 26. The base structure
itself includes a pair of substantially parallel side
members 31 and a plurality of openings 17 therein
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
12
(positioned at the four corners and midway along each end
member 32) for receiving the separate connectors 11. A
pair of substantially parallel end members 32
substantially perpendicular and connected to the side
members 31 are provided. Like the side members 31, the
end members 32 have an opening 17 therein at their
corners and midway therein for receiving the separate
connectors 11.
A first cross member 33 parallel the side members 31
with openings 17 at each end for receiving the separate
connectors 11 is disposed between and connected to the
end members 32. A second cross member 34a and third
cross member 34b, both parallel the end members 32, are
disposed between and connected to the side members 31.
Turning to Figure 10, there is shown a cross section
of an end member 32, which is similar to a side member 31
and cross member 33,34a,34b. The end members 32, like
the side members 31 and cross members 33,34a,34b, are
generally U-shaped in cross-section. In particular, at
the outermost sides (26), the end member 32 has two
horizontal longitudinal portions 41 which are integral
with upwardly projecting, substantially vertical
longitudinal portions 42 which, in turn, are connected to
a centrally located second horizontal longitudinal
portion 43. This second horizontal longitudinal portion
43 is positioned above the first horizontal longitudinal
portions 41 adjacent the sides. Thus, the concave
surface formed by the upwardly projecting longitudinal
portions 42 and second horizontal longitudinal portion 43
of the end members (and the side members and cross
members) is the outer surface 22.
There are two parallel intermediate substantially
vertical longitudinal portions 44 running parallel to the
upwardly projecting, substantially vertical longitudinal
portions 42. These intermediate longitudinal portions 44
also form the outer surface 22 of the base 20.
Intersecting the vertical longitudinal portions 42
and passing through the intermediate longitudinal
portions 44 are a plurality of spaced-apart vertical
CA 02207281 1997-06-06
WO 96/17783 PCT/US95I15896
13
transverse portions 50. Each vertical transverse portion
50 terminates at a vertical longitudinal portion 42.
Holes 51 are formed between the vertical
longitudinal portions 42 and each intermediate
longitudinal portion 44 and between the intermediate
longitudinal portions 44 in the space between the
vertical transverse portions 50.
The inner surface 21 (Figure 5) is relatively smooth
and U-shaped with the plurality of spaced, parallel
transverse inner ribs 38 integral with the inner surfaces
of the first horizontal longitudinal portion 41, upwardly
projecting longitudinal portions 42 and the second
horizontal longitudinal portion 43. The innermost
surface 38a of the transverse inner ribs 38 act as guides
or ramps for the forklift tines. Thus, if a tine hits
the inclined surface 38a, rather than pushing the pallet,
it will slide along the incline to its proper position.
As noted, the inner surface 21 and outer surface 22
of side members 31 and cross members 33,34a,34b are
similar to the end members 32 just described.
There are twelve (12) connectors, six (6) separate
connectors and six (6) integral, built-in connectors.
As to the separate connectors 11, openings 17 are
formed by sleeves and spokes built at the corners and
midway along the end member 32 at the point where the
first cross member 33 intersects thereto of the base 20
for cooperating therewith.
As shown in Figures 4, 5 and 8, the base 20 has
openings 17 adapted to receive the tangs of the
connectors 11. The openings 17 are surrounded by
circular, outer recessed abutments 61 that are recessed
below the plain of the adjacent outer surface 62, 22 of
the base. The recessed abutments 61 are formed by a
substantially vertical first annular wall 64 and a
substantially vertical second annular wall 65. The outer
recessed abutments 61 are generally circular and
connected along with the first and second annular walls
64,65 by spokes 63 to the vertical transverse and
longitudinal portions 42,44,50 (Figure 5).
CA 02207281 1997-06-06
WO 96/17783 PCT/LTS95/15896
14
To assist in guiding, orienting and seating the
connectors and for added protection, substantially
vertical guide walls or posts 66 are formed into the base
20 in the inner surface 21 thereof. The guide walls 66
are contoured to follow the external corner surfaces of
the connectors.
Similarly, at the places where the connectors are
attached, the first horizontal longitudinal portion 41
and the transverse inner ribs 38 are replaced by vertical
support walls 67. The connectors are seated on these
vertical support walls 67 and the guide walls 66 project
therefrom.
The connectors 11, discussed in detail below, can
thus be snapped into the base, on and adjacent to the
inner surface 21, by applying axial force to the
connectors so the barbs of the connectors will snap into
position onto the outer recessed abutment 61. With this
construction, the barbs will not extend out beyond the
outer plain of the outer surface 22. After all of the
connectors are assembled on one base, the deck is
positioned as shown in Figure 1 and a force is applied to
the outside surface of the deck to complete the assembly
of the plastic pallet.
Shown in Figure 4, the pallet base has a circular
support wall 69 projecting outwardly from the outer
surface 22 adjacent each of the corner connector openings
17. In addition, ports 68 are provided for adding molten
plastic under pressure to the mold for making the bases.
Excess molding material around the ports 68 can be cut,
sanded or scraped off the final product.
Finally, as seen in Figure 4, "X-shaped" ribs 70 are
formed projecting outwardly from the outer surface 22 of
the base 20 adjacent the internal connectors (320).
C. The Deck
In the pallet, the base 20 is connected, via
separate connectors 11 and integral connectors lla, to a
deck 100 (shown in Figures 1 - 3, 6, 7, 8, 9 and 9A). It
is the deck the goods are placed on. The deck 100 has
two surfaces, namely an inner surface 121 (Figure 7) and
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
an outer surface 122 (Figure 6). The outer surface 122
is the surface which faces out from the pallet;
specifically it is the surface which faces up and
contacts the goods being palletized. The inner surface
5 121 is the surf ace facing the inside of the pallet , i . a . ,
the side the connectors are attached to, and the base 20.
The deck 100 is generally rectangular in shape. It
has a f first side 123 , an opposed second side 124 , a f first
10 end 125 and an opposed second end 126. The outer surface
122 is substantially planar and includes perimeter
reinforcement means. The end perimeter reinforcement
means and side reinforcement means are similar and
(Figure 9) includes a substantially vertical perimeter
15 first outer wall 131 and a first inclined outer wall 132
integral with a second inclined outer wall 133. The
first inclined outer wall 132 includes a drain 134.
Spaced and parallel intermediate transverse walls 135 are
integral with and bridge the perimeter first outer wall
131 and the planar section of the inner surface 121.
In the alternative, as shown in Figure 9A, the side
and end perimeter reinforcement means may be configured
to include a substantially vertical perimeter first outer
wall 131a and an integral substantially vertical second
outer wall 133a, the second outer wall extending out
further from the base of the planar inner surface 121 of
the base 100 a further distance than the first outer
wall. Spaced and parallel intermediate transverse walls
135a or gussets having an inclined, exposed surface 135b
integral with and bridge the two perimeter outer walls
131a,133a and the planar section of the inner surface.
In this construction, no drain is necessary.
In practice, this second embodiment, Figure 9A, has
been shown to be stronger than the first embodiment,
Figure 9, in taking repeated, external strike forces
thereto.
Both the side and the end perimeter reinforcement
means are hooked-shape (Figure 9) or U-shaped (Figure 9A)
in cross-section. The concave surface of the
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
16
reinforcement means is the outer surface 122 in the hook-
shaped design (Figure 9) and the inner surface in the U-
shaped design (Figure 9a). The first inclined outer
walls 132 or the combination of the first and second
outer walls 131a,133a with the inclined surface 135b of
the transverse walls 135a act as guides or ramps for the
forklift tines. Thus, if a tine hits the inclined wall,
rather than pushing the pallet, it will slide along the
incline to its proper position.
The inner surface 121 of the deck has a
reinforcement structure projecting outwardly therefrom.
This reinforcement structure includes a plurality of
cells 151 formed by a plurality of parallel end walls 152
and a plurality of side walls 153. The cells 151 are
substantially rectangular and, apart from the perimeter
cells 151a, the cells 151 are approximately the same
size. The matrix formed by the end walls 152 and side
walls 153 is shown in Figure 7. Most of the perimeter
cells 151a include a second end wall 152a between the end
walls 152 and a second side wall 153a between the side
walls 153.
As discussed previously, there are preferably twelve
(12) connectors, six (6) separate connectors and six (6)
integral, built-in connectors. As to the separate
connectors 11, openings 117 are formed by sleeves and
spokes built at the corners and midway along the ends
125,126 of the deck 100 for cooperating therewith.
The openings 117 are adapted to receive the tangs of
the connectors 11. The openings 117 are also surrounded
by circular, outer recessed abutments 161 that are
recessed below the plain of the adjacent outer surface
122 of the base. The recessed abutments are formed by
and between a substantially vertical first annular wall
164 and a substantially vertical second annular wall 165.
The outer recessed abutments 161 are generally circular
and connected along with the first and second annular
walls 164,165 by spokes (in the form of webs) 163 to the
substantially vertical perimeter first outer wall 131 and
the end walls 152 or the side walls 153.
CA 02207281 1997-06-06
WO 96/17783 PCTlUS95/15896
17
To assist in guiding, orienting and seating the
connectors and for added protection, substantially
vertical guide walls or posts 166 are formed into the
deck 100 in the inner surface 121 thereof. These guide
walls also prevent the connectors from being knocked out
of position by misaligned forklift tines. The guide
walls 166 are contoured to follow the external corner
surfaces of the connectors. Upwardly projecting teeth
166a may also be used to assist in guiding the connectors
and preventing them from getting knocked out of place
when contacted. The sleeve of the connector being
positioned between the teeth 166a and the guide walls
166.
The channels 15,16 are kept unobstructed within the
pallet. As seen in Figure 7, the connectors ll,lla are
oriented and sized so the forklift tines can be inserted
into either side or end and pass, without obstruction,
through channels of a predetermined width, designated X
and Y, in the pallet.
As discussed before, the connectors 11, can thus be
snapped into the deck, on and adjacent to the inner
surface 121, by applying axial force to the connectors so
the barbs of the connectors will snap into position onto
the outer recessed abutment 161. With this construction,
the barbs will not extend out beyond the outer plain of
the outer surface.
As further seen in Figure 7, for added strength
there are centrally located central side walls 153a
generally bisecting the cells 151 and centrally located
central end walls 152a along and between the intermediate
openings along the ends. Moreover, it should be noted
that most of the cells 151 include apertures 155 for
drainage and to reduce the amount of material used. To
avoid the problem of having goods falling through the
deck, the apertures are not large.
Shown in Figures 6, 7 and 8, the pallet deck has a
circular support wall 158 projecting outwardly from the
inner surface 121. Spokes 158a project inwardly from the
circular support wall 158 and terminate at a circular
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
18
sleeve 158b for permitting rubber pads to be placed on
the opposite surface. As to the outer surface (Figure
6), rubber pads (not shown) may be secured in the spaces
designated 159 (formed by the circular support wall 158
and the circular sleeve 158b shown on the inner surface)
onto the outer surface 122. These pads (159) near the
corners can protect the base while it is stored and
stacked. The pads also assist in preventing the goods
resting on the outer surface of the deck from slipping.
Similarly, on the opposite surface (Figure 7), namely the
inner surface 122, similar circular pads, designated 159,
are provided on the inner surface. These pads 159, in
which there are four, contact the forklift tines that
pass between the connectors into either the side channels
15 or the end channels 16. Thus, if the forklift stops
abruptly, the pads will prevent the pallet from slipping
on the tines.
Turning again to Figure 7, the cells 151 diagonally
adjacent the openings 117 at the corners of the deck 100
include a diagonal intermediate cross wall 171. The
cells diagonally adj acent these cells 151 with a diagonal
intermediate cross member 171 include four inclined cross
walls 172 projecting inwardly from the corners of the
cell. An additional inclined cross wall 173 is present
in a further cell adjacent the one with the four inclined
cross walls 172.
In the center of the pallet base 100 (the four
center cells 151), there is an X-shaped support (and
force absorbing and directing) wall 174 formed within the
cells. Similarly, adjacent the connectors, as shown in
Figure 7, there are inwardly directing V-shaped 175
support, force absorbing and distributing walls formed
within the cells.
These inclined, diagonal X-shaped, V-shaped walls
not only add strength, but also assist in the mold making
process. The additional walls act as channels,
additional channels, to facilitate the flow of the
molten, pressurized plastic through the mold and to
reduce the natural resistance to such flow.
CA 02207281 2005-07-07
19
Directly opposite the four inclined cross walls 172 of
the inner surface 121, on the outer surface 122, are ports
168 for adding molten plastic under pressure to the mold for
making the decks. Excess molding material around the ports
168, like the ports 68 for the base, can be cut, sanded or
scraped off the final product.
D. The Separate Connectors
The details of one type of connector (circular) are
disclosed and claimed in the invention by the same inventors
of the present invention, embodied in U.S. Patent No.
4,843,976 for a PLASTIC PALLET. The details of a second
type of connector (rectangular) are shown in the present
Figures 11 - 15 and 11A.
Each connector 11 includes a hollow central circular
core 220 that has circumferentially spaced slots 222
extending from opposite ends thereof which produce first and
second sets of tangs 224, 226. Each tang 224, 226 is
identical in construction and has a barb 230 formed adjacent
the free, distal end thereof. Each barb 230 has a flat
lower surface 232 which extends perpendicular to the axis of
the core 220 and has a tapered outer surface 234 extending
from the outer edge to define a ramp.
In the illustrated embodiment, four tangs are shown for
each set 224, 226 with each tang spanning approximately
ninety degrees. The tangs of the respective sets 224, 226
are circumferentially offset so the slots forming one set of
tangs 224 are axially aligned with the centers of the
opposite set of tangs 226 (Figures 14 and 15).
The central core 220 also has a force absorbing flange
236 located at the center of the core 220 and equally spaced
from the two ends. Forces applied to the tangs are
transmitted to the flange 236 where they are dissipated.
The connector I1 also includes a large rectangular
sleeve 244 surrounding the core 220 and is connected thereto
by radially extending spokes 246 and transverse spokes 247.
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
The radial spokes 246 project from the core 220 at
locations between the slots 222 forming the tangs 224, 226
(Figures 12 and 13). The radial spokes 246 are radially
spaced from each other, as shown in Figure 12, at three
5 different angles, that being angle A, angle B and angle
C. In the embodiment shown, angle A is 50 degrees, angle
B is 45 degrees and angle C is 35 degrees. The angles
for the radial spokes 246 are designed so the spoke
absorbs external, inwardly directed forces to the outer
10 sleeve 244. In practice, it has been found that forces
caused by misaligned forklift tines striking the
connectors, are resisted better when the radial spokes
are oriented as shown. For example,.as angle B increases
the distance between the spokes at each spoke's junction
15 with the sleeve, also increases, widening the distance
between supports. The widening in distance between
supports translates to an increase in the risk of
breakage between supports. Of course the number of
spokes may be increased, however, this adds to weight and
20 amount of material used and to further complications in
the molding process. Accordingly, a balance is made
between these factors.
The transverse spokes 247 add transverse support to
the radial spokes 246 and assist in distributing forces
applied to the sleeves 244. The transverse spokes 247
also assist in minimizing the movement, and thus the
weakening, of the radial supports 246.
Other spoke 246,247 configurations are possible.
For example, Figure 11A shows a connector 11 with a
different transverse spoke 247.
The upper and lower edges of the spokes 246,247 and
the sleeve 244 define planes P (Figure 15) which extend
perpendicular to the axis of the core 220.
The openings 17 in the base 20 and the deck 100 are
adapted to receive the tangs 224, 226 . Each opening 17 is
surrounded by an abutment 61,161 recessed below the
adjacent surface of the deck or the base. The abutment
61,161 is sized such that the distance between the plane
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
21
P and the flat lower surface 232 of the barb 230 allows
the barbs to snap into position (See Figure 8).
To assemble the pallet 10, the connectors 11 are
first assembled to a first piece, either the base 20 or
the deck 100, by aligning a set of tangs 224,226 with the
opening 17 and then applying an axial force which causes
the ramps 234 of the barbs 230 to deflect the tang
inwardly sufficient to allow the set of tangs to pass
through the openings. After the barb 230 has cleared the
abutment surface 61,161, the memory characteristics of
the plastic will snap the tangs back to their original
condition and lock the connector to the base or deck.
After all the connectors are assembled on the base or
deck, the other piece, i.e., deck or base, is positioned
above or below the piece with the connectors and the
openings therein are aligned. A force applied to the
outer surface of the second piece will similarly snap the
connectors to the second piece.
E. The Integral Internal Connectors
The details of the integral internal connectors of
the base and the deck are shown in Figures 16 - 20.
There are six (6) integral connectors (Figure 1). The
six integral connectors lla are positioned on the base 20
of the embodiment shown in two parallel rows with one (1)
at each of the junctions where the second cross member
34a and the third cross member 34b meets each of the side
members 31 and one (1) each at the junction of where the
first cross member 33 meets the second cross member 34a
and the third cross member 34b. The six integral
connectors lla are positioned on the deck 100 (Figure 7)
of the embodiment shown in two parallel rows between and
parallel the two ends 125,126, four (4) adjacent the
sides 123,124 (two sets - one set per side) and two
disposed between each set.
The integral connectors comprise a mating system.
The system of the base cooperates with the system of the
deck. Specifically, the system of the base 20 (Figures
4, 8, 16 and 17) includes a hollow central circular core
320 which has circumferentially spaced slots 322
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
22
extending from the distal end thereof which produce a set
of tangs 328. Each tang 328 is identical in construction
and has a barb 330 formed adjacent the distal end
thereof. Each barb 330 has a flat lower surface 332
which extends perpendicular to the axis of the core 320
and has a tapered outer surface 334 extending from the
outer edge to define a ramp.
In the embodiment shown, four tangs 228 are shown
with each tang spanning approximately ninety degrees.
The central core 220 is attached by crossing
integral spokes or webs 321 via a cylindrical web 323 to
the main body of the base 20.
And, the system of the deck 100 (Figures 7, 8, 18
and 19) includes a protective force absorbing oval sleeve
330 with inwardly projecting webs or spokes 331 and an
internal, central receiving core 332. The central
receiving core 332 has an opening 333 at the distal end
thereof. As with the openings 117 for the separate
connectors, there are means for receiving and seating the
barbs of the integral connectors 11a. In particular,
adjacent the outer surface 122 of the deck 100, there are
circular, outer recessed abutments 361 which are recessed
below the plain of the adjacent outer surface 122 of the
base. The recessed abutments are formed by and between
a substantially vertical first annular wall, the central
receiving core 322, and a substantially vertical second
annular wall 365. The outer recessed abutments 361 are
generally circular. The recessed abutment 361 sitting
below the adjacent outer surface 122 of the deck is sized
so it is greater than or equal to the distance between
the flat lower surface 332 of the barb 330 and the
outermost point of the taper or ramp 334. This allows
the barbs to snap into position and sit below the outer
surface 122 of the deck. (See Figure 8) . In addition,
tabs 335 are formed at the distal end of the central
receiving core to guide the tangs therein.
The central receiving core 332 with the opening 333
at the distal end thereof is sized so as to receive the
central core 320 with tangs 328 of the base 20. T o
CA 02207281 1997-06-06
WO 96/17783 PCT/US95/15896
23
assemble the pallet 10, the integral connectors lla are
aligned such that the central cores 320 of the base 20
face the receiving cores 332 of the deck 100. An axial
force is applied to the connectors lla which causes the
ramps 334 of the barbs 330 to deflect the tangs inwardly
sufficient to allow the tangs to pass through and within
the opening 333 of the receiving core 332. After the
barbs 330 have cleared the abutment surface 361, the
memory characteristics of the plastic will snap the tangs
back to their original condition and lock the connector
together. This can be done simultaneously with the
attachment of the separate connectors 11.
The two centrally located internal, integrated
connectors lla (Figure 7) on the deck 100 also have
projecting barbs 350. As shown in the cross-section of
Figure 20, at opposed sides on the oval sleeve 330 a
projecting post 354 is formed which supports the barb.
Each barb 350 has at its distal end a flat lower surface
352 and ramp or taper 353. As seen in Figure 7, these
centrally located connectors are larger in size and
include additional internal transverse support ribs 351.
In addition, support webs 355 assist in reinforcing the
posts 354. These projecting barbs 350 of the posts 354
cooperate with small holes, designated 370 (shown in
Figures 4 and 5) , formed into the base 20. The holes 370
receive the post 354 and ramp section 353 of the barbs
350 and slide into a snap fit relationship with the
application of an axial force. This additional locking
mechanism is for added safety. If for any reason other
connectors were to fail, the additional posts 354 and
barbs 350 act to keep the components together. 'IY~ two
primary pallet components, namely the base and the deck,
are preferably injection molded from recycled material,
such as polypropylene or similar thermoplastic material.
Additionally, a pigment may be added to provide color
combinations to suit the customer's needs.
Of course, the size, shape and the number of
separate and integral internal connectors can be varied
without departing from the spirit of the invention.
CA 02207281 2005-07-07
24
It will be appreciated that the simplicity of the
plastic pallet reduces the inventory substantially since
only two primary components are necessary. Also, since the
base or deck only require recessed shoulders formed in
wells, the molds for producing the large decks are greatly
simplified to reduce production costs.
The intricate design of the connectors has several
distinct advantages. The design is such that all external
forces are transmitted to the center of the core, which will
withstand the greatest force without destruction.
Furthermore, the connectors are configured so they can be
formed as one piece in a single stage mold to reduce the
cost. Since the connectors and the decks are preferably
injection molded from recycled plastic, the costs are
further reduced.
Another significant advantage of the plastic pallet is
that the connectors can easily be separated should one of
the connectors become damaged. This can be accomplished by
the owner without return of the pallet assembly to the
manufacturer.
Removal of connectors or the separation of components
can be accomplished very easily with the aid of a simple
tool, such as the one shown and claimed in the patent by the
same inventors of the present invention, U.S. Patent No.
4,843,976 for a PLASTIC PALLET.
While the specific embodiments have been illustrated
and described, numerous modifications come to mind without
significantly departing from the spirit of the invention and
the scope of protection is only limited by the scope of the
accompanying claims.
