Double deck plastic pallet

A plastic pallet has a twin sheet thermoformed upper deck reinforced with a tubular metal substrate. Injection molded plastic octagonal posts have support member walls which are positioned beneath reinforced portions of the top deck. The posts also have a sleeve with a central bolt hole which is parallel to the support member walls. A twin sheet thermoformed lower deck is spaced from the upper deck by the posts and receives the posts in recessed pockets. Plastic bolts are inserted through the top deck, each post, and the bottom deck and are held in place by plastic T-nuts. The pallet is sealed against entry of liquid into the interior space of the pallet and may be stored on a flat surface or elevated on a rack.

FIELD OF THE INVENTION 
The present invention relates to pallets in general and to pallets having 
connected upper and lower decks in particular. 
BACKGROUND OF THE INVENTION 
Pallets are used in the manufacture, transportation and storage of a wide 
variety of products. A palletized load may be conveniently packed by the 
manufacturer, transported, stored in stacks or racked, and delivered to 
the end user conveniently and efficiently. Although wooden pallets are 
widely used, wooden pallet quality is variable due to variations in wood 
and assembly techniques. Furthermore, exposed nails and wood splinters as 
well as the inherent difficulties in maintaining wood surfaces in a 
sanitary condition make wooden pallets undesirable in industries such as 
the food and canned goods industries, where high levels of sanitation are 
required. 
Plastic pallets have been employed to overcome some of these drawbacks of 
wooden pallets. In particular, pallets have been formed by a process of 
twin sheet thermoforming which are durable and easily cleaned. 
In an effort to extend the usable lifetime of a pallet, pallets are known 
which utilize two decks joined by replaceable legs or posts. The pallet 
legs, which come into repeated contact with the sharp metal tines of 
forklift vehicles, are subjected to the most intense wear of any part on 
the pallet. In these pallets, a damaged leg may be removed from the double 
deck assembly and replaced with a fresh leg at a cost far less than 
replacing the entire pallet. Known replaceable legs generally are 
cylindrical, and bolted between upper and lower decks, or have employed 
various barbed geometries to allow a snap-fit connection between upper and 
lower decks. 
Due to the inherent material properties of plastic and the desire for an 
overall light-weight pallet, in applications requiring the support of 
heavy loads the plastic upper deck of the pallet has been reinforced with 
metal rods or tubular metal substrates. 
Reinforced double deck pallets are known which utilize snap fit posts. Snap 
fit posts, however, are subject to failure when placed in tension and also 
require specialized tools to remove. 
What is needed is a double deck reinforced plastic pallet of high 
load-carrying capacity which may be economically formed and maintained in 
a sanitary condition and which has leg posts which are durable and which 
are easily replaced. 
SUMMARY OF THE INVENTION 
A double deck plastic pallet has a twin-sheet thermoformed top deck with a 
planar load bearing surface with peripheral edges. A reinforcing metal 
substrate is located within the top deck. A twin-sheet thermoformed bottom 
deck is spaced beneath the top deck and a plurality of plastic posts 
extend between the top deck and the bottom deck. Each post has a 
vertically extending support member which is engaged against the lower 
plastic sheet beneath the metal substrate of the top deck in load bearing 
relation. Each post also has a sleeve portion which is integrally formed 
with the support member. The post sleeve portions are horizontally spaced 
from the substrate. The twin-sheet thermoformed top and bottom decks are 
of closed cell construction and the posts are engaged within pockets in 
the bottom deck which seal the posts against entry of liquids. 
It is an object of the present invention to provide a double deck plastic 
pallet with a metal reinforced top deck which effectively transmits the 
loads carried by the reinforcing structure to pallet support posts. 
It is also an object of the present invention to provide a double deck 
plastic pallet with easily attachable support posts. 
It is another object of the present invention to provide a double deck 
plastic pallet with twin sheet thermoformed upper and lower decks. 
It is a further object of the present invention to provide a double deck 
pallet which is sealed against the entry of liquids into the interior of 
the pallet. 
It is yet another object of the present invention to provide a double deck 
plastic pallet with four-way entry for the tines of a lift vehicle which 
may be stored in stacks or edge-racked. 
It is a still further object of the present invention to provide a double 
deck pallet with posts which may be quickly and effectively replaced when 
damaged. 
Further objects, features and advantages of the present invention will 
become apparent from the following specification when taken in conjunction 
with the following drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring more particularly to FIGS. 1-36, wherein like numbers refer to 
similar parts, a double deck plastic pallet 20 is shown in FIG. 1-14, with 
the component parts of the pallet 20 illustrated in FIG. 1. The pallet 20 
is comprised of a twin-sheet thermoformed top deck 22 which is spaced from 
a twin-sheet thermoformed bottom deck 24 by a plurality of extruded 
plastic posts 25, 26, 27. The decks and posts are secured together by a 
plurality of T-bolts 28 and nuts 30. 
The top deck 22 and the bottom deck 24 of the pallet 20 are manufactured by 
a twin-sheet thermoforming process. Each deck 22, 24 is thus formed from 
two heated sheets of thermoplastic resin material which are vacuum formed 
and fused together to form a unitary plastic structure. The thermoplastic 
sheets may be of virgin high density polyethylene. The structure of the 
pallet 20 is designed, however, to advantageously utilize recycled 
polyethylene materials, such as may be derived from recycled milk bottles. 
The top deck 22 of the pallet 20 is formed from an upper plastic sheet 32, 
shown in FIG. 6 and a lower plastic sheet 34 shown in FIG. 8, which 
enclose a tubular metal substrate 36. 
The substrate 36, shown in hidden view in FIG. 6, is formed of bent and 
welded square steel tubing. The substrate 36 is inserted between the upper 
and lower sheets 32, 34 of the top deck 22 during the twin sheet 
thermoforming process, and is secured between the two sheets 32, 34 when 
they are fused together at multiple pinch points. The metal substrate 36, 
which is significantly stronger and stiffer than the plastic material of 
the top deck 22, serves to reinforce the top deck 22 to yield a top deck 
capable of supporting much greater loads than an unreinforced plastic deck 
without objectionable deflection of the deck surface. 
In many applications fully loaded pallets are stored in vertical racks 
which have support brackets which extend inwardly beneath the bottom deck 
24. For best performance, the reinforcing substrate should extend as close 
to the peripheral edges 37 of the top deck 22 as is possible. The 
substrate 36 has peripheral members 38 with radiused corners 40 
conveniently formed from a single length of bent tubing. Linear interior 
members 42 are welded to the peripheral members 38 and a center member 44 
is welded to two interior members 42 somewhat off center. As shown in FIG. 
9, the peripheral members 38 are closely spaced from the peripheral edges 
37 of the top deck 22. 
Additional rigidity is imparted to the top deck by a pattern of reinforcing 
ribs 46, as shown in FIG. 8, which are formed in the lower sheet 34 of the 
top deck and which are fused to the upper sheet 32 of the top deck. The 
reinforcing ribs 46 are placed in separated areas to allow the insertion 
of the grid-like metal substrate 36 without interference with the ribs 46. 
As shown in FIG. 6, the top surface 48 of the upper sheet 32 is 
substantially planar. The uninterrupted planar expanse of the top surface 
48 provides a smooth surface for unhindered loading and unloading of the 
pallet 20. The smooth surface facilitates cleaning by allowing the spilled 
contents of containers loaded on the top deck 22 to be easily removed. 
The pallet 20 is of closed cell construction, which is particularly 
desirable for applications in the food industry. It is important for 
sanitation that there be no entrances for liquids, particularly organic 
material and bacteria, into the interior of a deck between the upper and 
lower sheets. Therefore, the bolt holes 50 which pierce the top deck 22 
are drilled through sealed pinch points in the top deck where portions of 
the upper sheet 32 are fused to the lower sheet 34. Rectangular bolt head 
pockets 52, shown in FIGS. 7 and 9, are formed in the upper sheet 32 of 
the top deck 22 and receive the rectangular heads of the T-bolts 28. The 
bolt head pockets 52 and bolt holes 50 are horizontally spaced from the 
peripheral members 38 and radiused corners 40 of the substrate 36 and do 
not pass through or intersect any portion of the substrate 36. Exposure of 
the substrate to moisture, dirt, solvents, corrosives, contaminants or 
chemicals commonly found in the workplace would create unsanitary 
conditions as well as limit the effective life of the pallet. The T-bolts 
28 preferably do not pass through the tubing of the reinforcing substrate 
36, but pass along side of it. However, for most effective transmittal of 
loads from the metal substrate 36 to the bottom deck 24, it is desirable 
that the load-carrying portions of the post 26 be located directly below 
the tubular metal members of the substrate 36. The posts 26 are 
particularly designed to permit the effective transfer of loads from the 
substrate 36 to the bottom deck 24 while being connected to the top and 
bottom decks 22, 24 by bolts which do not pass through the substrate 36. 
As shown in FIGS. 10, 11 and 12, the posts 26, 27 are formed of extruded 
plastic material of constant cross-section with a generally teardrop 
shaped exterior profile, best shown in FIG. 11. Each post 26, 27 is formed 
of two structurally distinct but integrally joined portions 54, 56. The 
post 26 is composed of a support member 54 which is generally cylindrical 
with generally cylindrical vertically extending walls 55 and with a 
vertical central axis 58 located at the center of the cylindrical support 
member 54. The support member 54 has an exterior radius of approximately 
1.2 inches. The wall thickness of the support member 54 is approximately 
fifteen hundredths of an inch. Two reinforcing members 60 are integrally 
formed within the support member 54 in a cross shape and extend vertically 
within the support member 54. 
A bolt sleeve 56 is integrally formed with the support member 54 and has 
portions defining a vertical bolt hole 62. The bolt hole 62 is parallel to 
the central axis 58 of the support member 54 and is spaced from the 
central axis 58 so that the bolt hole is located exterior to the support 
member walls 55. The sleeve 56 is roughly cylindrical and has an exterior 
radius of approximately sixty-five hundredths of an inch and a wall 
thickness of approximately fifteen hundredths of an inch. The support 
member 54 and sleeve 56 of the post 26 share a common wall 64 but are each 
isolated from one another and the voids within each portion 54, 56 are 
non-communicating. The two joined cylindrical portions of the posts 26 
give the posts 26 a somewhat teardrop shaped cross-section with the sleeve 
56 serving to protect the T-bolt 28 inserted therein from damage and the 
support member 54 serving to carry the loads imposed upon the pallet top 
deck 22. The center post 25 and the corner posts 27 are identical to the 
side posts 26, although the corner posts may be formed with an upwardly 
extending portion as described below. 
As shown in FIG. 6, the T-bolts 28 are inserted through the top deck 22 at 
different positions with respect to the metal substrate 36 depending on 
whether a post 26 is located at a corner 66 or intermediate between the 
corners along a linear side 67 of the top deck 22. As shown in FIG. 8, the 
side posts 26 are located along the sides 67 of the top deck with the 
support member 54 of the post directly beneath the substrate peripheral 
members 38 and with the sleeve 56 located inwardly from the peripheral 
members 38. By positioning the bolt holes 50 inward of the peripheral 
members 38 of the substrate 36, the peripheral members 38 may be 
positioned as close as possible to the peripheral edges 37 of the top deck 
to insure substantial reinforcement of the pallet 20 when rack mounted. 
At the pallet corners 66, the substrate 36 has radiused corners 40 which 
are hence spaced somewhat from the peripheral edge 37 of the top deck 22 
at the pallet corners 66. At the corners 66, it is not necessary to have 
reinforcement very close to the peripheral edge as the pallets 20 when 
rack mounted do not require that the corners 66 be engaged by the racks. 
Hence, the corner posts 27 are oriented with the support member 54 
positioned beneath the radiused corners 40 of the substrate 36 and with 
the sleeve 56 located radially outwardly from the substrate 36. The center 
post 25 is positioned with the support member 54 directly below the center 
member 44 and with the sleeve 56 offset from the position of the substrate 
center member 44. 
The bottom deck 24 of the pallet 20 is also formed by a twin-sheet 
thermoforming process from an upper sheet 68, shown in FIG. 3, which is 
fused to a lower sheet 70, shown in FIG. 5. The bottom deck 24 supports 
the pallet and its contents when the pallet 20 is in storage either on a 
supporting surface or stacked upon another loaded pallet. The bottom deck 
24 of the pallet 20 is not reinforced, although for particular 
applications a reinforcing substrate may be supplied within the bottom 
deck. 
The bottom deck 24 is formed to facilitate four-way entry of the tines of 
an automotive or hand-operated forklift. Ramps 72 are formed in the bottom 
deck 24 between each pair of posts 26, 27. For clarity, the posts 25, 26, 
27 have been omitted from the cross-sectional view of FIG. 3. The ramps 72 
are formed by inclined portions of the upper sheet 68 which are fused to 
supporting ribs 74 formed on the lower sheet 70 and shown in FIGS. 4 and 
5. Pockets 76, 77 are formed in the bottom deck 24 and are positioned 
beneath the posts 25, 26, 27 and are adapted to snuggly receive the posts 
within the bottom deck 24. 
The ramps 72 assist in smooth entry of the tines of a forklift vehicle 
beneath the top deck 22. The ramps 72 also serve to direct the tines away 
from contact with the posts 25, 26, 27 and hence contribute to longer post 
life. Four clearance holes 78 are routed out of the bottom deck 24 to 
provide clearance for the bearing wheels of a hand forklift tine. Ribs 80 
are formed on the lower sheet 70 and fused to the upper sheet 68 to 
support the generally planar upper surface 82 of the bottom deck 24. 
As best shown in FIGS. 3 and 9, each pocket 76, 77 has a platform 84, 85 
raised approximately one-half inch above a floor 86, 87, respectively. The 
corner pockets 77 are formed with the platform 85 located radially 
outwardly from the floor 87. The floor 87 is a pinch point where the upper 
and lower sheets 68, 70 of the bottom deck 24 are fused together. A hole 
89 is drilled through the floor 87 and the T-nut 30 is inserted 
therethrough. A nut head recess 91, shown in FIG. 5 is formed beneath the 
floor 87. The post pockets 76 located in the center and on the sides of 
the bottom deck 24 are generally teardrop in shape and are positioned 
directly below the corresponding posts 25, 26. The pockets 76 have 
platforms 84 raised above pocket floors 86 and have holes 88 formed in the 
platforms 84 for the admission of T-nuts 30 and have T-nut head recesses 
90 formed beneath the platforms 84. The pockets 76, 77 locate the posts 
25, 26, 27 and seal the open ends of the posts against the admission of 
liquid or debris. 
As best shown in FIGS. 9, 10, 11 and 12 each post 25, 26, 27 has a recessed 
portion 92 formed at its base with a radius of approximately one and one 
eighth inch which is dimensioned to fit snuggly over the elevated 
platforms 84, 85. The base 94 of each post is comprised of portions of the 
support member 54 and is positioned on the floor 86, 87 of a pocket 76, 
77. The raised platforms 84, 85 above the nut recesses 90, 91, allow the 
lower sheet 70 of the bottom deck to be without any downward protrusions 
which would destabilize the pallet. The load-bearing support members 54 
bear directly against the floors 86, 87 of the pockets 76, 77 which are 
formed of solid plastic material at pinch points between the upper and 
lower sheets 68, 70 of the bottom deck 24 and thus may transmit their 
loads directly to a bearing surface such as a floor or a truck bed or onto 
the loaded pallet beneath in a stacked array of pallets. The center post 
25 is identical to the side posts 26 shown in FIG. 10 and has a planar top 
96. The corner posts may be formed identically with the side posts 26, 
however, as shown in FIGS. 7 and 12, the corner posts 27 are formed with a 
protruding upper portion 98 to form a tight seal against the recessed 
corners 100 of the top deck 22. Alternatively, the corners 100 may be 
formed with a recess on the top surface of the deck to permit the use of 
standardized posts at all post positions. 
The pallet 20 is assembled, as best shown in FIG. 1, by inserting posts 25, 
26, 27 between the top deck 22 and the bottom deck 24 and aligned within 
the pockets 76, 77. Identical T-bolts 28 are then inserted through the 
bolt holes 50 in the top deck 22 through the sleeves 56 of the posts 25, 
26, 27, through the bolt holes 88, 89 in the bottom deck 24 where they are 
secured by the T-nuts 30 which are best shown in FIGS. 13 and 14. The 
T-nuts 30 have a head 102 with anti-turn ribs 104 formed radially thereon 
which mate within radial recesses 106 within the nut recesses 90, 91 on 
the lower sheet 70 of the bottom deck 24. 
The assembled pallet 20 may be reused multiple times. Should a particular 
post be damaged due to some mishap or extended wear, that post may be 
unbolted from the pallet 20 assembly and replaced with a new post. The 
damaged post may then be returned for recycling. A loaded pallet 20 may be 
stored on a support surface, in stacked array, or on elevated racks. 
It should be noted that for added snugness additional pockets corresponding 
to the shapes of the post tops 96 may be formed in the lower sheet 34 of 
the top deck 22 to receive the posts. 
An alternative embodiment of the double deck plastic pallet 120 of this 
invention is shown in FIGS. 15-28, with the component parts of the pallet 
120 illustrated in FIG. 15. The pallet 120 is comprised of a twin-sheet 
thermoformed top deck 122 which is spaced from a twin-sheet thermoformed 
bottom deck 124 by a plurality of injection-molded plastic posts 125. The 
decks and posts are secured together by a plurality of bolts 128 and nuts 
30. Each bolt 128 has a square head which is captured by a pocket 152 in 
the top deck 122. 
The top deck 122 and the bottom deck 124 of the pallet 120 are manufactured 
by a twin-sheet thermoforming process. Each deck 122, 124 is thus formed 
from two heated sheets of thermoplastic resin material which are vacuum 
formed and fused together to form a unitary plastic structure. The 
thermoplastic sheets may be of virgin high density polyethylene. The 
structure of the pallet 120 is designed, however, to advantageously 
utilize recycled polyethylene materials, such as may be derived from 
recycled milk bottles. 
The top deck 122 of the pallet 120 is formed from an upper plastic sheet 
132, shown in FIG. 18 and a lower plastic sheet 134 shown in FIG. 19, 
which enclose a tubular metal substrate 136. 
The substrate 136, shown in hidden view in FIG. 18, is formed of bent and 
welded square steel tubing. The substrate 136 is inserted between the 
upper and lower sheets 132, 134 of the top deck 122 during the twin sheet 
thermoforming process, and is secured between the two sheets 132, 134 when 
they are fused together at multiple pinch points. The metal substrate 136, 
which is significantly stronger and stiffer than the plastic material of 
the top deck 122, serves to reinforce the top deck 122 to yield a top deck 
capable of supporting much greater loads than an unreinforced plastic deck 
without objectionable deflection of the deck surface. 
The reinforcing substrate 136 extends closely spaced from the peripheral 
edges 137 of the top deck 122. As shown in FIG. 18, the substrate 136 has 
peripheral members 138 with radiused corners 140 conveniently formed from 
a single length of bent tubing. Linear interior members 142 are welded to 
the peripheral members 138 and a center member 144 is welded to two 
interior members 142 somewhat off center. 
Additional rigidity is imparted to the top deck by a pattern of reinforcing 
ribs 146, as shown in FIG. 19, which are formed in the lower sheet 134 of 
the top deck and which are fused to the upper sheet 132 of the top deck. 
The reinforcing ribs 146 are placed in separated areas to allow the 
insertion of the grid-like metal substrate 136 without interference with 
the ribs 146. 
As shown in FIG. 18, the top surface 148 of the upper sheet 132 is 
substantially planar. The uninterrupted planar expanse of the top surface 
148 provides a smooth surface for unhindered loading and unloading of the 
pallet 120. The smooth surface facilitates cleaning by allowing the 
spilled contents of containers loaded on the top deck 122 to be easily 
removed. 
The pallet 120 is of closed cell construction, which is particularly 
desirable for applications in the food industry. It is important for 
sanitation that there be no entrances for liquids, particularly organic 
material and bacteria, into the interior of a deck between the upper and 
lower sheets. Therefore, the bolt holes 150 which pierce the top deck 122 
are drilled through sealed pinch points in the top deck where portions of 
the upper sheet 132 are fused to the lower sheet 134. Square bolt head 
pockets 152, shown in FIG. 15, are formed in the upper sheet 32 of the top 
deck 122 and receive the square heads of the bolts 128. The bolt head 
pockets 152 and bolt holes 150 are horizontally spaced inwardly from the 
peripheral members 138 and radiused corners 140 of the substrate 136 and 
do not pass through or intersect any portion of the substrate 136. 
Exposure of the substrate to moisture, dirt, solvents, corrosives, 
contaminants or chemicals commonly found in the workplace would create 
unsanitary conditions as well as limit the effective life of the pallet. 
The bolts 128 preferably do not pass through the tubing of the reinforcing 
substrate 136, but pass along side of it. However, for most effective 
transmittal of loads from the metal substrate 136 to the bottom deck 124, 
it is desirable that load-carrying portions of the post 125 be located 
directly below the tubular metal members of the substrate 136. The posts 
125 are particularly designed to permit the effective transfer of loads 
from the substrate 136 to the bottom deck 124 while being connected to the 
top and bottom decks 122, 124 by bolts which do not pass through the 
substrate 136. 
Posts 125, best shown in FIGS. 20-26, are stiff octagonal plastic support 
columns which carry the loads applied to the top deck 122 to the bottom 
deck 124. For reduced weight and cost, each post 125 is not solid, but is 
comprised of a number of integral walls and webs of approximately 
one-eighth inch thickness. Each post has eight walls 221, 223, 225: two 
outside walls 221, which are perpendicular to one another and aligned with 
the sides of the pallet 120; two inside walls 223 also perpendicular to 
one another and spaced in parallel relation from the outside walls 221; 
and four corner walls 225, which are shorter than the inside and outside 
walls and which connect adjacent inside and outside walls. It is the post 
outside walls 221 which engage against and support the 
substrate-reinforced portions of the top deck. The outside walls 221--and 
those corner walls 225 adjacent thereto--act as a support member for 
transferring much of the load from the reinforced portions of the top deck 
122 to the bottom deck 124. 
A square tubular bolt sleeve 231, which is open at the top and bottom, is 
centered within the post 125. A generally L-shaped stiffening column 233 
extends vertically within the post 125 adjacent the sleeve 231 with the 
two legs 235 of the L defining portions of the bolt sleeve 231. Vertically 
extending planar webs 239 extend from the outside and inside walls 221, 
223 to the stiffening column 233. Two webs 241 extend from opposed corner 
walls 225 to the stiffening column 233 and bolt sleeve 231. The corner 
wall webs 241 define an axis of symmetry for the post 125. 
The stiffening column 233 extends above the height of the walls 221, 223, 
225 to form an L-shaped protrusion 243 which is closed by a planar surface 
245. On the bottom of each post 125, as best shown in FIG. 25, an 
octagonal depression 247 is formed which is centered within the post 125. 
A surface 249 recessed within the post defines the upper limits of the 
depression 247. A planar ring octagonal surface 251 defines the bottom of 
the post 125. 
As best shown in FIG. 22, the surfaces 245, 249, 251 form a barrier which 
prohibits the passage of gasses, liquids, dirt or particulate matter 
through the post 125 at any location except for through the bolt sleeve 
231. Each outside wall 221 has a recess 253 formed therein and extending 
vertically. Each recess 253 is adapted to receive an adhesive label 
containing machine-readable information relevant to the contents of a 
particular pallet. Labels 255 marked with conventional bar codes when 
placed on the outside walls 221 will be appropriately positioned for 
convenient data entry either by a portable scanner or a scanner fixed in 
the path of travel of a particular pallet. 
In an exemplary pallet, each post 125 is approximately five inches wide. 
The bolt sleeve 231 is approximately one inch wide. The post 125 is 
approximately four and five-eighths inches tall with the L-shaped 
protrusion 243 extending one-half inch above the top of the post. 
As shown in FIG. 27, structure is formed in the lower sheet 134 of the top 
deck 132 which engages with, locates, and supports against lateral 
deflection the posts 125. Surrounding each bolt hole 150 in the top deck 
122 on the lower sheet 134 is an octagonal ridge 257 with dimensions 
slightly greater than those of the post 125. The ridge 257 serves to 
locate the post 125 and also forms a seal around the post to reduce the 
admittance of liquids and other debris. The bolt hole 150 is centered 
within the ridge 257 and passes through a pinch point at one lobe 259 of 
the four-lobed X-shaped base 260 of a depression 261 formed within the 
octagonal ridge 257. The surface 263 which extends between the depression 
261 and the ridge 257 is at substantially the same level as the lower 
surface 265 of the top deck 122. The X-shaped base 260 of the depression 
261 is depressed approximately one and three-eighths inch from the surface 
263 within the ridge 257. A shoulder 267 is formed within the depression 
261 and is spaced approximately one inch from the base 260 and 
approximately three-eighths inch from the lower surface 265 of the top 
deck. The shoulder engages against the L-shaped protrusion 243 of a post 
125. 
The center of the depression 261 is offset from the center of the octagonal 
ridge 257. The placement of the depression 261 with respect to the bolt 
hole 150 is equivalent to the relation between the L-shaped protrusion 243 
and the bolt sleeve 231 on the post 125. This arrangement facilitates 
rapid assembly of the pallet 120 by permitting the quick and proper 
orientation of each post 125 within the octagonal ridge 257 such that the 
outside walls 221 of each post 125 will always face the outside of the 
pallet, hence permitting the bar code labels 255 to remain visible and the 
outside supporting walls to be always properly positioned with respect to 
the reinforcing substrate. The L-shaped protrusion 243 is supported on the 
shoulder 267 above three lobes 259 of the X-shaped base 260 such that a 
bolt sleeve 231 is properly aligned with the bolt hole 150. 
Protruding detents 269, shown in FIGS. 27 and 29, extend from the surface 
263 within the ridge 257. The detents 269 are located within the ridges 
257 along the corners and sides of the pallet 120 and serve to restrain 
inward deflection of the posts 125 as the result of a lateral blow from an 
obstacle or the tines of a forklift. As best shown in FIG. 17, the detents 
269 are spaced inwardly somewhat from the outside walls 221 of the post 
125 and do not snuggly engage said walls between the detents and the ridge 
257. When the post 125 is deflected, however, the detents 269 will prevent 
movement of the post against the bolt 128 which would tend to shear the 
bolt or otherwise damage it. 
As shown in FIGS. 17 and 26, octagonal pockets 176 are formed in the bottom 
deck 124. Each pocket 176 has an octagonal floor 186, which engages 
against the bottom surface 251 of a post 125. The floor is located at a 
pinch point where the upper and lower sheets 168, 170 of the bottom deck 
124 are fused together. A platform 184 is raised approximately 
seven-eights inch above the floor 186 and has a hole 188 drilled 
therethrough which is positioned beneath the bolt hole 150 in the top deck 
122 and beneath the sleeve 231 of a post 125. The platform 184 is also 
formed at a pinch point. A nut head recess 190 shown in FIG. 26 is formed 
beneath the platform 184. The pockets 176 thus surround the posts 125 
holding them in place and preventing the entry of liquids and dust into 
the posts. 
The bottom deck 124 of the pallet 120 is also formed by a twin-sheet 
thermoforming process from an upper sheet 168, shown in FIG. 17, which is 
fused to a lower sheet 170, shown in FIG. 26. The bottom deck 124 supports 
the pallet and its contents when the pallet 120 is in storage either on a 
supporting surface, racked or stacked upon another loaded pallet. The 
bottom deck 124 of the pallet 120 for moderate loads need not be 
reinforced, although for particular applications a reinforcing substrate 
may be supplied within the bottom deck, as described below. 
The bottom deck 124 is formed to facilitate four-way entry of the tines of 
an automotive or hand-operated forklift. Ramps 172 are formed in the 
bottom deck 124 between each pair of outside posts 125. The ramps 172 are 
formed by inclined portions of the upper sheet 168 which are fused to 
supporting ribs (not shown) formed on the lower sheet 170 similar to ribs 
74 in the pallet 20. Pockets 176 are formed in the bottom deck 124 and are 
positioned beneath the posts 125, and are adapted to snuggly receive the 
posts within the bottom deck 124. 
The ramps 172 assist in smooth entry of the tines of a forklift vehicle 
beneath the top deck 122. The ramps 172 also serve to direct the tines 
away from contact with the posts 125 and hence contribute to longer post 
life. Four clearance holes 178 are routed out of the bottom deck 124 to 
provide clearance for the bearing wheels of a hand forklift tine. Ribs are 
formed on the lower sheet 170 and fused to the upper sheet 168 to support 
the generally planar upper surface 182 of the bottom deck 124. 
The pallet 120 is assembled, as best shown in FIG. 1, by inserting posts 
125 between the top deck 122 and the bottom deck 124 and aligned within 
the pockets 176 and ridges 257. Identical bolts 128 are then inserted 
through the bolt holes 150 in the top deck 122 through the sleeves 231 of 
the posts 125 through the bolt holes 188 in the bottom deck 124 where they 
are secured by the nuts 30 which are best shown in FIGS. 13 and 14. The 
nuts 30 have a head 102 with anti-turn ribs 104 formed radially thereon 
which mate within radial recesses 106 within the nut recesses 190 on the 
lower sheet 170 of the bottom deck 124. 
The assembled pallet 120 may be reused multiple times. Should a particular 
post be damaged due to some mishap or extended wear, that post may be 
unbolted from the pallet 120 assembly and replaced with a new post. The 
damaged post may then be returned for recycling. A loaded pallet 120 may 
be stored on a support surface, in stacked array, or on elevated racks. 
In particular applications, for example when palletizing particularly heavy 
loads, it is desirable to employ a pallet 281 having a bottom deck 293 
which is reinforced with a metal substrate 295. This substrate is 
preferably formed of square steel tubing approximately three-quarters inch 
wide. As shown in FIGS. 29-36, the reinforced bottom deck pallet 281 
utilizes a top deck 122, bolts 128, and nuts 30, which are identical in 
all respects to those of the pallet 120. 
The tubular metal substrate 295, shown in hidden view in FIG. 30, has 
peripheral members 297 and interior members 299 which are molded between 
the bottom deck upper sheet 301 and the bottom deck lower sheet 303. The 
upper and lower sheets 301, 303 are fused such that the substrate 295 is 
entirely enclosed within the plastic material and is not exposed to the 
environment. 
The reinforced bottom deck 293 is connected to the top deck 122 by nine 
posts 305. Each post 305 for the reinforced bottom deck pallet 281 is 
similar to the post 125 in the pallet 120 and has inside and outside walls 
307, 309 connected by corner walls 311 with an interior sleeve 313 and 
stiffening column 315 joined by webs 317 to the walls 307, 309, 311. The 
post 305 also has an L-shaped protrusion 319 identical to the protrusion 
243 on the post 125. 
Because of the placement of the metal substrate 295 around the perimeter of 
the bottom deck 293, octagonal pockets such as those on the pallet 120 may 
not be formed at a constant depth within the bottom deck. The reinforced 
bottom deck 293 has bolt holes 321 formed at pinch points between the 
upper sheet 301 and lower sheet 303 above a nut recess 323 for receiving 
the nut 30. Two polygonal protrusions 325 extend upwardly from the upper 
sheet 301 beneath each post 305. Each post 305 has two polygonal recesses 
327, which are shaped to receive and engage against the protrusions 325. 
The recesses 327 extend inwardly from a planar bottom surface 329 of the 
post 325. The engagement of the protrusions 325 within the recesses 327 
prevents the posts 305 from rotating within the assembled pallet 281. At 
least one outside wall 309 of each post 305 is thus in a position above 
the metal substrate 295 to transmit loads from the top deck to the bottom 
deck 293. 
The recesses 327 are five-sided, generally in the shape of a rectangle with 
a single truncated corner. Each recess 326 is like an inverted cup which 
extends from the planar base 330 of the post 305. Each recess 327 has an 
upper polygonal surface 328 which engages against the upper surface 331. 
The walls 333 of the recess which extend from the upper surface 331 to the 
base 330 of the post 305 may engage against the walls 335 of the 
protrusion 325 to restrict horizontal motion of the post 305 with respect 
to the bottom deck 293. 
As shown in FIGS. 32 and 33, the walls 307, 309, 311 of the posts 305 for 
use with the reinforced bottom deck will preferably be seven-eighths of an 
inch shorter than the walls of the post 125 for use with an unreinforced 
bottom deck. The overall height of a pallet 281 will thus be substantially 
the same as the height of the pallet 120. 
Although the pallets 120,281, have been illustrated with nine posts, a 
greater or lesser number of posts may be employed depending upon the 
requirements of a particular application. In addition, although octagonal 
posts have been shown, polygonal posts having more or fewer sides may be 
employed. Furthermore, the rib structure formed on the lower sheets of the 
top and bottom decks may be replaced by equivalent designs of varying 
appearance. It should also be noted that while the corners of the tubular 
metal substrate have been shown as radiused, angular welded corners may 
also be employed. Also, the interior framework of the metal substrate may 
be modified to suit particular applications and stress concentrations. 
It is important to note that the present invention is not limited to the 
particular construction and arrangement of parts disclosed and illustrated 
herein, but embraces all modified forms thereof as come within the scope 
of the following claims.