U.S. patent number 3,638,586 [Application Number 05/043,682] was granted by the patent office on 1972-02-01 for pallet.
This patent grant is currently assigned to Crown Zellerbach Corporation. Invention is credited to Anthony E. Elshout.
United States Patent |
3,638,586 |
Elshout |
February 1, 1972 |
PALLET
Abstract
A four-way entry pallet of a construction enabling it to be made
of molded plastic material to provide lightness without sacrifice
of strength, comprises top and bottom walls, two pairs of opposite
sidewalls having openings for receiving tines of a lift fork,
reinforcing connecting columns between the top and bottom walls,
and openings in the top and bottom walls, providing lightness. The
top wall comprises T-shaped reinforcing ribs which provide strength
and rigidity. Some of the openings in the bottom wall are enlarged
to accommodate supporting wheels on tines of a lift fork, and have
opposite bevelled edges providing ramps for such wheels; and lower
edges of openings in the sidewalls are also bevelled to provide
such ramps.
Inventors: |
Elshout; Anthony E. (San
Francisco, CA) |
Assignee: |
Crown Zellerbach Corporation
(San Francisco, CA)
|
Family
ID: |
21928349 |
Appl.
No.: |
05/043,682 |
Filed: |
June 5, 1970 |
Current U.S.
Class: |
108/57.28;
108/901 |
Current CPC
Class: |
B65D
19/0012 (20130101); B65D 2519/00318 (20130101); B65D
2519/00407 (20130101); Y10S 108/901 (20130101); B65D
2519/00273 (20130101); B65D 2519/00308 (20130101); B65D
2519/00557 (20130101); B65D 2519/00069 (20130101); B65D
2519/00562 (20130101); B65D 2519/00288 (20130101); B65D
2519/00034 (20130101) |
Current International
Class: |
B65D
19/00 (20060101); B65d 019/18 () |
Field of
Search: |
;108/51,58 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Gay; Bobby R.
Assistant Examiner: Finch; Glenn O.
Claims
I claim:
1. A pallet comprising an integrally bonded molded structure
including a top wall, a bottom wall, two pairs of opposite
sidewalls, each of said top and bottom walls having a plurality of
spaced openings therein which lighten the structure and which leave
flat webs about openings extending between each pair of opposite
walls, upright reinforcing columns integrally joined to top and
bottom webs to provide a rigid connection between such top and
bottom walls, reinforcing flanges integral with and narrower than
such top webs and forming therewith T-shaped reinforcing ribs
extending between each pair of opposite sidewalls, at least one
pair of opposite sidewalls each having spaced-apart openings to
receive tines of a lift fork with the openings in each of said
opposite walls in alignment with the respective openings in the
opposite wall, four of the openings between webs in the bottom wall
each adjacent a corner of the pallet being enlarged to accommodate
supporting wheels on the tines with a pair of such enlarged
openings in alignment with each pair of opposite tine receiving
openings, and the flat bottom webs including a web extending
substantially between each pair of such enlarged openings upon
which said wheels can ride.
2. The pallet of claim 1 wherein opposite edges of each enlarged
bottom opening in alignment with a pair of tine-receiving openings
are bevelled to provide ramps to allow said wheels to ride
thereover.
3. The pallet of claim 1 wherein said flat bottom webs upon which
said wheels can ride are integrally connected to webs extending
transversely with respect thereto between opposite sidewalls of the
pallet, and said latter opposite sidewalls are provided with
aligned tine-receiving openings.
4. The pallet of claim 1 wherein opposite edges of each enlarged
bottom opening in alignment with a pair of tine-receiving openings
are bevelled to provide ramps to allow said wheels to ride
thereover, the lower edge of each tine-receiving opening is
bevelled also to provide such ramp, said flat bottom webs upon
which said wheels can ride are integrally connected to webs
extending transversely with respect thereto between opposite
sidewalls of the pallet, said latter opposite sidewalls are
provided with aligned tine-receiving openings, and wherein the
pallet is formed of plastic material comprising an upper section
and a lower section rigidly bonded together.
5. The pallet of claim 1 wherein said flat bottom webs include a
pair of spaced-apart webs located between said pairs of opposite
tine-receiving openings and which extend between said one pair of
opposite sidewalls and also webs extending transversely with
respect to said pair of spaced-apart webs, and wherein the webs
upon which the tine wheels can ride are wider than the
aforementioned spaced apart and transversely extending webs.
Description
SUMMARY AND OBJECTS
Summarizing the invention hereof, the pallet is rectangular in
horizontal shape and is made of relatively light weight plastic
material. It comprises top and bottom walls, and two pairs of
opposite sidewalls which are integrally connected together. The
walls are provided with apertures for lightening the pallet.
Each sidewall has spaced apart openings with the openings in one
sidewall aligned with the openings of the opposite sidewall, for
receiving lift fork tines which are insertable in either direction;
and the upright sides of such openings are flared or slanted
inwardly to guide the tines into the pallet without damaging the
pallet. Such tine receiving openings in one pair of opposite walls
are longer in width than those in the other pair of opposite
sidewalls to accommodate tines of different widths. Upright
reinforcing columns rigidly connect the top and bottom walls.
Tines of the forks of one well-known type of lift truck which is
hand operated, are supported at their front ends on wheels; and to
allow the wheels to enter between the top and bottom walls without
pushing the pallet, the lower edges of at least some of the tine
receiving openings in the sidewalls are bevelled to provide ramps
for allowing the wheels to ride readily into the pallet. Also, some
of the openings in the bottom wall are enlarged to receive such
wheels when the tines are inserted into the pallet; and opposite
edges of such openings are bevelled to provide ramps to facilitate
riding of the wheels thereover.
From the preceding, it is seen that the invention has as its
objects, among others, the provision of an improved pallet of a
construction enabling it to be made of light-weight plastic
material which can be molded, is of sturdy construction, is
provided with special reinforcing ribs to permit such lightweight
without sacrifice of strength or rigidity, and which is also
provided with bevels along lower edges of openings, which form
ramps over which wheels on the lift fork can ride without damaging
or pushing the pallet. Other objects of the invention will become
apparent from the following more detailed description and
accompanying drawings in which:
DESCRIPTION OF FIGURES
FIG. 1 is a plan view looking at the top of the pallet;
FIG. 2 is a side elevational view looking in the direction of arrow
2 in FIG. 1;
FIG. 3 is a horizontal section taken in a plane indicated by line
3--3 in FIG. 2;
FIG. 4 is a longitudinal vertical section taken in planes indicated
by line 4--4 in FIG. 1;
FIG. 5 is a side elevational view looking in the direction of arrow
5 in FIG. 1;
FIG. 6 is an enlarged fragmentary vertical section in the same
plane as the FIG. 4 section, illustrating how a wheel on a lift
fork tine is accommodated by the pallet and rides over bevelled
portions forming edges of openings in the pallet;
FIG. 7 is a fragmentary vertical section taken in a plane indicated
by lines 7--7 in FIG. 1;
FIG. 8 is an enlarged vertical section illustrating a bevelled edge
providing a ramp for a wheel on a lift fork tine, taken in the
plane indicated by line 8--8 in FIG. 3; and
FIG. 9 is an enlarged transverse vertical section of a T-shaped
reinforcing rib.
DETAILED DESCRIPTION
The pallet is advantageously of plastic material, desirably so
called foamed (aerated) high density polyethylene which has an
interior cellular structure and a solid exterior skin, and is
advantageously molded by well-known injection-molding technique.
Although foamed polyethylene is a desirable material because of
lightness and strength, other moldable thermoplastic or
thermosetting resins may be employed, such as acrylonitrile -
butadiene-styrene, polystyrene, polypropylene or polyesters.
With particular reference to FIGS. 1 through 4, the pallet is
rectangular in horizontal section, comprising top wall 2, bottom
wall 3, and a pair of opposite sidewalls 4 which are longer than
the other pair of opposite sidewalls 6, thus providing the
rectangular shape. The top surface of top wall 2 is planar; and
such wall is provided with a plurality of rows of spaced apart
openings 7 to lighten the structure, and which are desirably of
rectangular shape, except the intermediate openings adjacent
opposite sidewalls 6, which are trapezoidal in shape for a purpose
to be described. These openings form longitudinally extending flat
webs 8 therebetween, and also transversely extending flat webs 9.
The side edge portions (rim) of top wall 2 are formed of flat webs
11. Thus, strength and at the same time lightness obtains, which
are important. Reinforcing flanges 12 are integral with the
respective longitudinally and transversely extending webs 8 and 9,
but are narrower than such webs, thus forming top wall 2
essentially of T-shaped reinforcing ribs 8, 12, and 9, 12. Webs 11
which form the top wall rim, are provided with downwardly extending
flanges 13 along the inner edges thereof, thus also providing
reinforcement to enhance strength.
With particular reference to FIG. 3, it will be noted that bottom
wall 3 is also provided with a plurality of relatively small
openings 16, most of which are preferably rectangular in shape,
thus serving to lighten the structure. In addition, four large
openings 17 which are for the purpose of accommodating wheels on a
lift fork tine, are formed adjacent the respective corners of the
pallet. Openings 17 also lighten the pallet. The bottom openings
leave narrow flat webs 18 extending in a longitudinal direction,
and narrow flat webs 19 extending in a transverse direction.
Extending in a longitudinal direction midway of larger lift fork
wheel accommodating openings 17, are wide flat webs 21 over which
the wheels can ride.
Top and bottom walls 2 and 4 are rigidly and integrally joined or
connected together by a plurality of upright columns 22
rectangularly shaped in cross section, and by a plurality of
columns 23 which are L-shaped in cross section; and L-shaped
columns 24, which form part of the sidewalls of the pallet, are
provided at the respective corners of the pallet. Also, a
trapezoidal, cross-sectionally shaped column 26, connects the top
and bottom walls midway of each of the shorter sidewalls 6 and
between wheel accommodating openings 17 adjacent such sidewall. The
opposite surfaces of each column 26 and an adjacent corner column
24 taper or slant inwardly toward each other to provide guide
surfaces 26' for facilitating insertion of a lift fork tine. It is
for this reason that each column 26 is trapezoidal in
cross-sectional shape.
From the preceding it is seen that the four wheel accommodating
openings 17, each adjacent a corner of the pallet, are aligned
longitudinally and transversely in parallel rows. For insertion of
lift fork tines, the shorter opposite sidewalls 6 are provided with
spaced-apart openings 27 adjacent column 26; and narrower openings
28 are provided in each long sidewall 4 for a similar purpose; the
lateral edges adjacent such openings being slanted inwardly toward
each other as indicated at 30 for guiding such tines. In addition
to the tine-receiving openings the sidewalls 4 and 6 are desirably
provided with openings 29 which lighten the pallet.
The arrangement of tine receiving openings 27 and 28 in the
sidewalls is such that tines of a lift fork may be inserted
underneath the top of the pallet from any one of its sides, thus
providing a so called four-way entry pallet. In commercial use,
there are two well-known types of lift forks, one known as a hand
lift fork (hand operated jack mechanism) which has relatively long
and wide tines, the front end of each tine being supported on a
wheel as is illustrated schematically in FIG. 6. The wider tine
receiving openings 27 are for such wheel-supported tines. Another
type of lift fork in a power-operated fork which has narrower and
shorter tines now mounted on wheels, for which narrower
tine-receiving openings 28 are adapted.
Referring particularly to FIG. 6, in which a tine 32 supported at
its front end on wheel 33 is shown schematically, in order to
prevent the pallet from being pushed by the wheels when the tines
are inserted through side openings 27, the lower edge of each
opening 27 is bevelled (preferably at about a 45.degree. angle but
such angle is not critical), to slant upwardly from the bottom, to
thus form ramps 34 for allowing the wheels to ride over them
without pushing the pallet. When a wheel enters side opening 27 it
rides on a wide web 21, and then drops into enlarged wheel
accommodating or receiving opening 17 adjacent one side of the
pallet. Upon further insertion of the fork, the wheel then rides
over the opposite edge of opening 17 onto a wide web 21 and then
into the enlarged opening 17 at the opposite side of the pallet,
whereupon the pallet can be lifted.
The opposite edges of each of these wheel-accommodating openings 17
in alignment with the opposite side openings 27, are also bevelled
in the same direction as ramps 34 to provide ramps 36 for the
purpose described, thus facilitating insertion of the wheels, and
minimizing damage to the pallet. The ramps 34 and 36 are all as
shown in FIG. 8. When a wheel is moved into one wheel-accommodating
opening 17 and from that opening toward the opposite opening 17, it
is supported by and rides over wide bottom webs 21.
Although the wider tine-receiving openings 28 in sides 4 are not
primarily intended to receive wheel-supported tines, their lower
edges are desirably bevelled to provide ramps 37 for the purpose of
deflecting the end of a tine into the opening should it strike such
lower edge, thus minimizing damage to the pallet.
As previously related, the pallet is formed of molded material. Its
construction is such that it can be molded in two individual
sections in two separate molds; the sections being rigidly bonded
together after being molded, either by welding of the material
itself or by a strong adhesive, such as an epoxy resin, thus
forming an integrally bonded molded structure. The molded sections
are an upper section and a lower section, which are bonded together
along a plane indicated by the dotted line 38 in FIG. 2, which is
in the plane of the section line 3--3 in such FIG.
In the embodiment of the invention illustrated, the pallet has an
overall width of about 40 inches, an overall length of about 48
inches, an overall height of about 51/8 inches, and each
wheel-accommodating opening 17 is about 11 inches long and 9 inches
wide. In this connection, FIGS. 1 through 3 are of substantially
the same scale, thus the other dimensions can be readily determined
from the dimensions given. The pallet made from foamed (aerated)
high density polyethylene, aerated to a density of about 0.6,
weighs about 26 pounds. Although the pallet is desirably of plastic
material, it can be made of other material, such as metal, and the
features thereof, particularly the ramp construction and the
T-shaped top reinforcing ribs will provide the advantages
discussed.
* * * * *