U.S. patent number 3,889,839 [Application Number 05/474,797] was granted by the patent office on 1975-06-17 for blow-molded drum.
This patent grant is currently assigned to Advanced Chemical Technology. Invention is credited to Klaus S. Butz, Alvin L. Simon.
United States Patent |
3,889,839 |
Simon , et al. |
June 17, 1975 |
Blow-molded drum
Abstract
The peripheral wall of a blow-molded plastic drum is provided
with recesses positioned at diametrically opposite sides, adjacent
the top of the drum. Each includes a substantially flat horizontal
surface functioning as a bearing surface for the forks of a
fork-lift truck. A handling attachment can be provided at the top
of the drum to accept the top hook of a hand truck or a similar
transporting device.
Inventors: |
Simon; Alvin L. (Los Angeles,
CA), Butz; Klaus S. (Los Angeles, CA) |
Assignee: |
Advanced Chemical Technology
(Los Angeles, CA)
|
Family
ID: |
23884975 |
Appl.
No.: |
05/474,797 |
Filed: |
May 30, 1974 |
Current U.S.
Class: |
220/675;
220/604 |
Current CPC
Class: |
B65D
39/084 (20130101); B65D 1/16 (20130101); B65D
25/22 (20130101) |
Current International
Class: |
B65D
39/00 (20060101); B65D 39/08 (20060101); B65D
1/16 (20060101); B65D 1/00 (20060101); B65D
25/22 (20060101); B65d 007/42 () |
Field of
Search: |
;220/72,70,69,66,5R |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Price; William I.
Assistant Examiner: Pollard; Steven M.
Attorney, Agent or Firm: Kleinberg; Marvin H.
Claims
What is claimed is:
1. A blow-molded drum of thermoplastic material comprising:
an extended drum body having a circumferential wall and top and
bottom sections,
said circumferential wall having at least two integral overhanging
brow portions positioned respectively on opposite sides of said
circumferential wall of said body, each of said brow portions
overhanging a corresponding clear and open volume adjacent said
circumferential wall sufficiently large to permit insertion of the
forks of a fork lift beneath the overhanging brows,
said overhanging brow portions having bottom surfaces adapted to
serve as bearing and lifting surfaces for lifting and transporting
of said drum by the forks of a fork lift.
2. The blow-molded drum defined by claim 1 wherein said brow
portions are positioned in the circumferential wall of said body
adjacent to the top of said drum body and substantially equidistant
above the bottom of said body.
3. The blow-molded drum of claim 1 wherein said circumferential
wall is generally cylindrical with slightly tapering top and bottom
portions.
4. The blow-molded drum defined by claim 1 wherein said clear and
open volumes are defined by two indentations in opposite sides of
said circumferential wall of said body, each of said indentations
being extended lengthwise to define longitudinal channels in said
circumferential wall through which the forks of a fork lift can be
inserted, said overhanging brow portions comprising the respective
overhanging top portions of said longitudinal channels.
5. The blow-molded drum defined by claim 1 wherein each of said
overhanging brow portions has at its deepest portion a depth in the
range of 3/2 of an inch to 11/2inches.
6. The blow-molded drum defined by claim 1 wherein said overhanging
brow portions have at their deepest portion a depth of at least 1/2
inch.
7. The blow-molded drum defined by claim 6 wherein the clear and
open volume beneath an overhanging brow portion has a height of
approximately 11/2 inches.
8. The blow-molded drum defined by claim 1 wherein said bottom
surfaces of said overhanging brow portion are planar surfaces
substantially normal to the axis of said drum, said circumferential
wall including longitudinally extended upright wall sections
immediately beneath and joining to said bottom surfaces of said
overhanging brow portions.
9. The blow-molded drum of claim 1 wherein said drum body includes
a handling member positioned at the top of said body and adjacent
said circumferential wall and adapted to receive the handling hook
of a hand truck.
10. The drum defined by claim 9 wherein said handling attachment
comprises a loop of flexible material attached to said drum
body.
11. The drum defined by claim 9 wherein said handling comprises a
cup-like receptacle integrally formed in the plastic of the top of
said drum body.
12. The drum defined by claim 1 wherein said bottom section of said
drum body includes a bottom enclosing end wall and said top section
of said drum body has an open top adapted to receive a mating
plastic cover.
13. A blow-molded drum of thermoplastic material comprising:
a substantially cylindrical body having opposite ends;
at least two indentations in the circumferential wall of said body
at diametrically opposite sides thereof, said indentations having
planar bearing surfaces disposed substantially normal to the
longitudinal axis of said drum, said indentations being
proportioned and adapted to receive the forks of a mechanical fork
lift for lifting and transporting said drum on said planar bearing
surfaces.
14. The drum of claim 13 wherein said opposite ends constitute top
and bottom end walls of said body and said indentations extend
equidistant from and adjacent to said top end wall.
15. The drum of claim 13 wherein said body has a longitudinal axis
and includes a head portion and a plurality of indentations
provided in the circumferential wall of said head portion at
diametrically opposite sides thereof and positioned symmetrically
relative to the longitudinal axis of said body.
16. The drum of claim 13 wherein said opposite ends constitute top
and bottom end walls of said body, said indentations being
positioned on the circumferential wall of said body equidistant
above the bottom end walls of said body.
17. The drum of claim 13 wherein said opposite ends constitute top
and bottom end walls of said body, said body being open at its top
and said indentations being positioned on the circumferential wall
of said body adjacent to the open top of said body and equidistant
above the bottom end wall of said body.
18. The drum of claim 13, wherein said opposite ends constitute top
and bottom end walls of said body, and includes at least one
depression formed at one side of the top end wall, and further
including a tubular projection affording access to the interior of
said body and located in said depression.
19. The drum of claim 18 wherein said tubular projection is
integrally formed with said depression in said planar end wall at
the top of said body, said drum further including reinforcing webs
integral with said end wall and said tubular projection and
bridging said depression.
20. The drum of claim 19 wherein said tubular projections are
provided with an inner circumferential surface and screw threads in
said surface, said screw threads being adapted to intermesh with
the screw threads of a plug member positioned in said tubular
projection to seal the latter from the atmosphere.
21. The drum of claim 13 further including a handling member for
manually and mechanically manipulating said drum, said handling
member being positioned at the top of said drum adjacent said
circumferential wall of said drum.
22. The drum of claim 21 wherein said opposite ends constitute
planar end wall surfaces at the top and bottom of said body, the
planar end wall surface at the top of said body being formed with
at least one depression at the side of said surface, and further
including a tubular projection affording access to the interior of
said body located in said depression, and wherein said handling
member is positioned laterally adjacent one of said tubular
projections.
23. The drum of claim 22 wherein said handling member is a loop of
flexible material cooperatively engaged with said one of said
tubular projections.
24. The drum of claim 21 wherein the planar end wall surface at the
top of said body is formed with at least one depression at one side
of said surface and a tubular projection affording access to the
interior of said body located in said depression, and wherein said
handling member is in the form of a receptacle constituted by a
wall section positioned radially outwardly and spaced from said
tubular projection and defining a cavity in said surface in the
region of the peripheral edge thereof, said cavity extending
inwardly of said body.
25. The drum of claim 13 wherein said opposite ends constitute a
top and bottom end of said body, said body being open at its top,
said drum including a handling member positioned adjacent the
peripheral edge bounding the open top of said body and adapted to
receive the handling hook of a hand truck.
26. The drum of claim 25 wherein said handling member is in the
form of a loop of flexible material and said peripheral edge
includes a laterally outwardly directed projection defining an
opening therethrough for the passage of said loop of flexible
material.
27. A blow-molded drum of thermoplastic material comprising:
a substantially cylindrical main body portion having a longitudinal
axis;
slightly curved head and bottom portions at axially opposite ends
of said main body portion and integral therewith, said head and
bottom portions terminating into substantially planar end
walls;
at least two indentations in the circumferential wall of said head
portion at diametrically opposite sides thereof, equidistant from
and adjacent to the planar end wall of said head portion, said
indentations having planar bearing surfaces axially aligned
relative to each other and disposed substantially normal to the
longitudinal axis of said drum, said planar surfaces being adapted
to receive supporting members for lifting and transporting said
drum;
depressions in the planar end wall at the top of said body at
diametrically opposite sides of said end wall;
a tubular projection affording access to the interior of said body
located in each of said depressions; and
a handling member for manually and mechanically manipulating said
drum, said handling member being positioned laterally of said end
wall at the top of said body, adjacent said tubular projection.
28. The drum of claim 27 wherein said handling member is in the
form of a loop of flexible material cooperatively engaging said
tubular projection.
29. The drum of claim 27 wherein said handling member is in the
form of a receptacle constituted by a cavity defined by a fold
portion being an extension of said tubular projection and including
an outer wall spaced from and substantially parallel with one side
of said tubular projection facing away from the center of the top
of said drum, and a base wall bridging said outer wall and said one
side of said tubular projection at the lower ends thereof.
30. A blow-molded drum of thermoplastic material having an open
top, comprising:
a substantially cylindrical main body portion having a longitudinal
axis;
slightly curved head and bottom portions at axially opposite ends
of said main body portion and integral therewith, said head portion
terminating into an upper free edge constituting the open top of
said drum, and said bottom portion terminating into a substantially
planar end wall;
at least two indentations in the circumferential wall of said head
portion at diametrically opposite sides thereof, equidistant from
and adjacent to said upper free edge, said indentations having
planar bearing surfaces axially aligned relative to each other and
disposed substantially normal to the longitudinal axis of said
drum, said planar surfaces being adapted to receive supporting
members for lifting and transporting said drum; and
a handling member for manually and mechanically manipulating said
drum, said handling member being moveably attached to said upper
free edge of said top portion of said body.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to containers and, more
particularly, to a blow-molded drum of the stackable type, made of
a thermoplastic material.
2. Description of the Prior Art
Drums of this kind are known in the art and are physically
configured to be stacked on top of each other for economy of space
requirements. One such conventional blow-molded drum comprises, for
example, a substantially cylindrical main body and a head and
bottom portion which are considerably tapered inwardly, relative to
the longitudinal axis of the drum, to provide the required
structural strength for the container.
The head and bottom portions of this conventional drum terminate in
generally planar end walls with depressions formed at diametrically
opposite sides of the top end wall. A tubular portion or projection
is located in each of the depressions and constitutes an inlet, an
outlet or an air escape opening. Each of the tubular projections
communicates with the interior of the drum. The upper open edges of
the projections terminate in a plane corresponding to the general
plane of the top wall surface.
Usually, reinforcing webs are provided in the respective
depressions and are integrally formed with the projections and the
center portion of the top end wall to add rigidity to the
projections and enhance the stability of the overall top end wall
surface. The reinforcing webs define an opening or cutout portion
below the upper edges of the projections and insure that the
tubular projections will not be subjected to deformation. Also, the
projections are provided with inner peripheral surfaces which
include a threaded portion adapted to intermesh with the threaded
portion of a bung or closure cap which, normally, seals the tubular
projections, isolating the interior from the environment.
Conventionally, this type of plastic drum is provided with an
eyelet positioned in the central portion of the top end wall
intermediate the depressions therein. For example, it may be
disposed in a recess beneath the general plane of the end wall.
This centrally positioned eyelet accepts the hook of a crane or
similar lifting device for vertical lifting or positioning of the
drum during loading or unloading thereof.
Loading and unloading of a fully loaded drum onto and from a
truckbed, platform or other location, by means of the eyelet and a
lifting hook, has the inherent disadvantage that, during aerial
travel of the drum by, for example, a crane, the tension exerted on
the drum in the region of the eyelet is exceedingly high,
particularly with those drums which have a large volumetric
content. It will be appreciated that as a result of this tension,
centered solely on the carrying eye or eyelet of the drum, breakage
or disengagement of the eyelet from the drum top surface may occur,
which, in turn, can affect the integrity of the drum and lead to
extremely hazardous situations.
The keg-shape of conventional plastic drums prevents normal manual
handling thereof as compared with the common steel drum which is
substantially cylindrical with relatively flat top and bottom
surfaces and can be easily rolled and positioned onto the platform
of a lifting device. Also, the top and bottom edges of the steel
drums usually have a rolled bead in a ring-shaped configuration,
which enables a standard fork truck to lift the drum. Plastic drums
of the type under discussion do not have such well defined edge
portions due to the degree of curvature at the top and bottom
portions, and hence, these drums are unsuitable for use with a
fork-lift truck.
Moreover, due to the highly curved or rounded top and bottom
sections of conventional keg or egg-shaped plastic drums, it is
nearly impossible to make use of a standard hand truck for handling
and transporting these drums. The support forks, which project
outwardly from the lower end of the truck, are rather short in
length and, as such, usually cannot reach the bottom surface of
such configured drums. Even in instances where the curvature at the
bottom section would allow the forks to engage the bottom surface
of the drum, it is extremely difficult to balance the drum on the
hand truck, again as a result of the general curved configuration
of the drum. In addition, the absence of any kind of handling
attachment leaves the drum in an unbalanced, relatively unstable
position on the truck.
SUMMARY OF THE INVENTION
It, therefore, is an object of the invention to overcome the above
disadvantages encountered with conventional blow-molded, plastic
polyethylene drums and to provide a drum which enables easy
handling both manually and mechanically using conventional lifting
devices.
According to a preferred embodiment of the invention, a drum of
substantially cylindrical configuration has slightly curved top and
bottom sections, terminating in generally planar end walls.
The drum is made of a high density thermoplastic material, such as
polyethylene, and is blow-molded in the conventional manner.
Provided in the generally straight, circumferential wall of the
drum, adjacent the top thereof, are a pair of indentations or
recesses positioned diametrically opposite each other. Each recess
provides a generally flat surface which extends substantially
normal to the longitudinal axis of the drum, parallel to the planar
top end walls thereof.
The purpose of providing the circumferential wall with such flat
recessed indentations is to provide bearing surfaces for the
straight and flat forks of a conventional fork-lift truck. The
indentations are configured to support the entire weight of a fully
filled drum and do not affect the structural strength of the drum.
Also, as a result of the cylindrical circumference and flat bottom
surface of the drum, the latter, when positioned on the forks or
bottom plate of a hand truck, is easily balanced against the
upwardly directed supports of the hand truck, a feature which,
hitherto, was impossible due to the rounded configuration of the
circumferential surface of the conventional plastic drums.
Furthermore, due to the provision of the substantially cylindrical
circumferential wall and the slightly curved top and bottom
portions of the drum, edge portions are formed between the
circumferential wall and the top and bottom surfaces. Such an edge
portion at the bottom region of the drum enables the latter to be
easily manually rolled and, in addition, enables the drum to be
adequately engaged by and positioned onto the forks or plate of a
standard hand lift truck. The degree of curvature at the bottom of
the drum is such as to enable the rather short forks to be easily
disposed beneath the drum bottom surface, a feature which, as
hereinbefore discussed, was practically impossible, again as a
result of the rather large curvature at the bottom portions of
conventional plastic drums.
Another feature of the invention not found in prior art blow-molded
drums is the handling attachment which further facilitates handling
and lifting of the drum by a hand truck. The handling attachment is
positioned at the drum top and enables the top to be connected to
the conventional top hook with which the hand truck is usually
equipped to connect the upper end of the drum to the truck. The
handling attachment may, of course, also be used to accept the hook
or connecting member of a similar lifting device which utilizes the
hook or connecting member for stabilizing the drum on the
device.
The handling attachment, in one embodiment thereof, is in the form
of a flexible loop attached laterally to the bung projection at the
top wall of the drum. The loop is arranged to accept the top hook
of the hand truck.
In another embodiment, the handling attachment is formed by a wall
receptacle which extends slightly angularly inwardly from the
planar surface at the top wall of the drum, adjacent the peripheral
edge thereof, and defines a cutout portion between the drum side
and bung projection. With the drum positioned on the forks of the
hand truck, the cutout portion accepts the top hook of the hand
truck.
Further features and advantages of the invention will be best
understood from the following description of specific embodiments
when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side view of a blow-molded polyethylene drum according
to the present invention;
FIG. 2 is a fragmentary side view of the drum of FIG. 1,
illustrating the upper portion of the drum turned through
90.degree., more clearly showing the handling attachment and the
wall indentation;
FIG. 3 is a fragmentary top view of the drum top of FIG. 2,
illustrating the handling attachment;
FIG. 4 is a fragmentary side view similar to FIG. 1, however,
illustrating a second embodiment of the handling attachment
according to the present invention;
FIG. 5 is a top plan view of the drum taken along the line 5--5 of
FIG. 4;
FIG. 6 is a fragmentary enlarged longitudinal section taken along
the line 6--6 of FIG. 5, illustrating in detail the handling
attachment;
FIG. 7 is a fragmentary view similar to FIG. 2, however,
illustrating an open-top drum incorporating the indentations and
the handling attachment of the present invention; and
FIGS. 8a and 8b are fragmentary views showing profiles of other
embodiments of lifting portions of a drum.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings in which like reference numerals
index like parts and, with attention initially directed to FIG. 1,
there is shown a blow-molded drum 10 which is made of a
thermoplastic material such as a heavy density polyethylene. The
drum is of substantially cylindrical configuration and, as shown,
has a generally straight periphery 12 and slightly curved top and
bottom portions 14, 16, respectively, which terminate in generally
planar top and bottom end walls 18, 20, respectively.
Provided in the circumferential wall of the top portion 14,
adjacent the top end wall 18, are two recesses or indentations 22,
24 positioned diametrically opposite each other in the top portion
14.
The recesses 22, 24 initially define curved shoulder sections 26,
28, which deflect rather sharply from the generally straight line P
of the projected periphery 12, inwardly relative to the
longitudinal axis A of the drum 10. The curved sections 26, 28
merge into substantially straight upright sections 30, 32, which
extend upwards in general alignment with the longitudinal axis A of
the drum 10 and extend lengthwise to form longitudinal channels in
the side walls of the drum through which the forks of a fork lift
can be run in for the purpose of lifting the drum. The sections 30,
32, in turn, terminate in overhanging brows or lips having planar
surfaces 34, 36, which extend in a normal plane relative to the
axis A of the drum 10.
When the straight surfaces 34, 36 are engaged and lifted by the
forks of, for example, a standard fork-lift truck, they provide
bearing surfaces for the forks and effect equal and uniform weight
distribution of a filled drum.
As shown in the preferred embodiment of FIG. 1, the fork insertion
recesses 22 and 24 are provided on the top portion 14 of the drum.
This location for the recesses gives greatest stability and
avoidance of tipping in the lifting of a fully loaded drum, because
the center of gravity of the fully loaded drum then lies well below
the supporting forks. It should be understood that, if desired,
additional recesses may be provided in the top portion, to permit
fork lift approach from different angles, and also that the
recesses may be positioned in other drum portions. Thus, for
example, the drum may be provided in its middle portion with
diametrically opposed recesses similar to 22 and 24. Also it may be
desired that the drum be as readily liftable by a fork lift when
the drum is upside down, and in such event the bottom portion of
the drum may be provided with an oppositely disposed pair of
recesses, having a configuration as shown in FIG. 8a, or a more
central portion of the drum may be provided with pair of recesses
having a configuration with both top and bottom lifting brows as
shown in FIG. 8b.
The planar surfaces of the recesses in the respective wall sections
are dimensioned as later discussed so as to prevent their
dislodgement from the forks.
On the whole, the top and bottom portions 14, 16 have a curvature
with a deflection of only a few degrees relative to the straight
sides 12 of the drum. This slight degree of curvature is sufficient
to give great structural strength to the container at the top and
bottom sections.
One advantage of a drum thus configured is, for example, a
substantial increase in dimension of the bottom surface as compared
with bottom portions of drums with a considerably high degree of
curvature such as, for example, a keg- or egg-shaped drum. The
bottom surface of the present drum, for instance, permits positive
engagement with and support by the forks or platform of a standard
hand truck, which would not be feasible with a drum with a rather
strongly curved bottom section. Since the forks or platform of the
hand truck are relatively short in length, generally they would not
extend far enough to reach and adequately support the bottom
surface of such drums. Hence, the slight degree of curvature at the
bottom section 16 provides a larger bearing surface of the bottom
wall per se and, consequently, provides a greater support surface;
e.g., for the platform of a truck.
As shown in FIGS. 2 and 3, the top end wall 18 is provided with
bung projections 38, 40 of conventional design. The projections are
positioned in depressions 42, 44, which are disposed diametrically
opposite each other in the top end wall 18. The projections 38, 40
define openings therein which communicate the interior of the drum
with the atmosphere, the openings or bung holes being arranged to
receive the usual bungs or stoppers.
The upper edges of the projections 38, 40, as shown, are located in
the general plane of the top wall 18 while the upper edges of the
bungs, not shown, are positioned in the plane of the upper limits
of the projections. This arrangement provides that the overall
upper wall 18 is generally flat which, as will be appreciated,
provides increased stability in the stacking of the drums on top of
each other.
Reinforcing webs 46, one shown, are provided at the sides of the
projections 38, 40, extending inwardly towards the center of the
drum. Located below or extending through the web 46, as shown, is a
cutout or eyelet 48. The eyelet 48 forms an opening for the passage
of a loop-shaped, flexible member 50 which loosely surrounds the
bung projection 38. The flexible member 50, e.g., a flexible wire
cable, constitutes a handling attachment for the drum 10 in that it
is arranged to receive, for example, the upper connecting hook of a
standard hand truck, or the hook of a similar handling device. One
such arrangement is illustrated in FIG. 2 with the hook shown in
dashed lines.
FIGS. 4, 5 and 6 illustrate an alternative embodiment of the
handling attachment of the invention. The handling attachment, in
this instance, is in the form of a fixed receptacle 52, open at its
upper end. A downwardly directed, elongated cavity 54 is arranged
to receive the top hook of a hand truck or the hook of a similar
handling device.
The receptacle 52 is positioned laterally in the region of the
circumferential edge 56 of the top end wall 18 and is disposed so
that the walls of the cavity 54 extend at a slightly outwardly
inclined orientation relative to the longitudinal axis A of the
drum 10. The upper edges 58, 60, bounding the cavity 54, extend in
a plane parallel with the general plane of the top wall 18.
The receptacle 52, in essence, is formed by a substantially
wedge-shaped fold portion 62, including a bottom portion 64 and an
outer wall portion 66. The fold portion 62 is integrally formed
with a substantially rectangular base portion 68, including a bung
assembly 70. The bung assembly 70, as shown in FIG. 6, includes an
upper tubular portion 72 and the base portion 68 integrally formed
therewith.
The four sides of the base portion 68 include an inner side 74
facing towards the center of the drum and an outer side 76 facing
away from the center of the drum, the lower end of which is
integral with the bottom portion 64. As shown, the outer side 76 of
base portion 68 extends parallel with the outer wall portion 66 and
angularly inwardly relative to the axis A of the drum.
Connecting the outer wall portion 66 with the outer side 76 of the
base portion 68 are side surfaces 78, one of which is shown in FIG.
6.
The base portion 68 of the bung assembly 70 and the wedge-shaped
fold portion 62, integrally formed therewith, constitute a
substantially rectangular assembly when viewed from the top or
bottom.
The bung assembly 70 constructed as discussed hereinbefore is a
prefabricated unit formed, e.g., by an injection molding process.
To position the assembly 70 in the top end wall 18 of the drum, the
assembly is initially appropriately placed in the matrix used for
shaping the drum and the latter is subsequently formed around the
assembly 70 by a blow-molding process. It should be noted that the
assembly 70 is preferably of a plastic substance with a higher
melting point than that used for manufacturing the drum in order to
avoid deformation or melting of the prefabricated assembly 70, or
parts thereof.
Once the blow-molded drum, and the bung assembly 70 formed therein,
is removed from the matrix, the drum is formed with an elongated,
generally rectangular opening 82 provided in the top wall 18 and in
which the bung assembly is appropriately located. Bounding the
opening 82 is a generally rectangular wall 84, constituted by wall
sections 86, 88, 90 and a lateral wall section 92 which merges into
the side wall 14 of the drum.
The outer circumferential surface of the base portion 68 and the
fold portion 62 are provided with an integral circumferential rib
portion 98, and as a result of blow-molding the drum around the
assembly 70, the circumferential surface of the drum wall 84 is
formed with a corresponding peripheral portion 100; and these two
portions, i.e., the rib portion 98 and the portion 100 of the drum
wall 84, are in interlocking engagement with each other, as shown
in FIG. 6. Also, following blow-molding the drum, the vertex 102 of
fold portion 62 is in abutting engagement with an abutment surface
94 of an abutment portion 96 formed at the transistion region at
the lower end of wall section 92 and the side wall 14 of the drum.
Such abutment provides a reinforcing effect for the fold portion 62
and the wall section 92 in the region of the abutment portion
96.
Unitary with the drum top wall section 86 of the wall 84 and the
central portion 104 of the drum top surface 18 is a reinforcing web
106 provided to add to the rigidity of the bung assembly 70 and to
prevent deformation thereof.
The bung assembly 70 is provided with an inner annular
circumferential wall 108 which at its lower end is provided with a
threaded portion 110 which intermeshes with a correspondingly
threaded portion 112 of a common bung 114, positioned in the
assembly 70. Directly above the threaded portion 110 is an inwardly
tapering portion 116 which tightly abuts a seal 118 provided on an
inner tapering surface portion 120 of the bung. This arrangement
provides a positive seal of the interior of the drum. A seal cap
122 is provided on the assembly 70 to prevent the bung 114 from
being removed accidentally or surreptitiously.
As can be seen from FIG. 5, the cavity 54 has a width which is
substantially equal to the diameter of the tubular portion 72 of
the bung assembly 70, the width being dimensioned such as to
provide adequate access for the top hook of a standard hand
truck.
FIG. 7 shows an open-top, blow-molded plastic drum 10', normally
closed by a lid or cover member 124. The drum in this embodiment is
configured similarly in appearance as the drum of FIG. 1. The drum
10' at the top portion 14' thereof is provided with an integral
lateral projection 126 extending radially outwardly. The projection
126 is formed with an eyelet or opening 128 which provides passage
for the handling attachment 130 which, as in FIG. 1, is in the form
of a loop-shaped flexible member such as a looped wire 50' which
accepts the hook of a lifting device. As shown, the upper surface
132 of the projection 126 lies in the general plane of the top end
wall 134. The drum configuration of this embodiment is identical
with its counterpart of FIG. 1 and will not be described
further.
By way of example, the position and dimensions of the periphery of
the foregoing embodiments are arranged so that, as shown in the top
view of FIG. 5, the overhanging brow of a recess has its planar
lifting surface occupying an area bounded between a chord C of the
circumference of the drum and the corresponding arc subtended by
the chord. The longitudinal width of the brow, corresponding to the
length of chord C, subtends a central angle of approximately
62.degree. at A. The depth of the overhanging brow is at least 1/2
inch and preferably approximately 3/4 inch to 11/2 inches to
provide adequate support for the forks of a fork lift and allowance
for the variations in fork spacing, so as to assure that the
lifting brow will not fail and that the forks will not slip off.
The upright sections of the recesses have a height of approximately
11/2 inches to permit a reasonable initial misalignment with the
height or angle of the forks of the fork lift as may be encountered
when the fork lift approaches on an inclined or uneven
pavement.
The upright sections of the recesses may be slightly outwardly or
inwardly curved. This may facilitate positioning of the forks of a
lifting device into the recesses, as, for example, in those
instances where the forks do not extend in exact parallelism with
each other. In addition, such slightly outwardly curved upright
sections tend to add to the rigidity of the overall recess
structure. An outwardly directed curvature of the upright sections
is exemplarily shown by the dash-dotted line in FIG. 5.
Without further analysis, the foregoing will so fully reveal the
gist of the present invention that others can, by applying current
knowledge, readily adapt it for various applications without
omitting various features which, from the standpoint of prior art,
fairly constitute essential characteristics of the generic or
specific aspects of this invention, and therefore, such adaptations
are intended to be comprehended within the meaning and range of
equivalents of the following claims.
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