U.S. patent number 3,730,576 [Application Number 05/112,354] was granted by the patent office on 1973-05-01 for plastic container and latch.
This patent grant is currently assigned to The Plastic Forming Company, Inc.. Invention is credited to Peter T. Schurman.
United States Patent |
3,730,576 |
Schurman |
May 1, 1973 |
PLASTIC CONTAINER AND LATCH
Abstract
A plastic container having a body and a cover and provided with
a detachable latch for locking the cover to the body in a closed
position. A brace member is provided for reinforcing a shelf formed
by a segmental portion of the inner shell of the container
body.
Inventors: |
Schurman; Peter T. (Woodbridge,
CT) |
Assignee: |
The Plastic Forming Company,
Inc. (Woodbridge, CT)
|
Family
ID: |
22343452 |
Appl.
No.: |
05/112,354 |
Filed: |
February 3, 1971 |
Current U.S.
Class: |
292/246;
292/DIG.38; 292/87; 206/349; 292/DIG.53 |
Current CPC
Class: |
B65D
43/165 (20130101); Y10S 292/53 (20130101); B65D
2251/1016 (20130101); Y10T 292/0902 (20150401); Y10S
292/38 (20130101); Y10T 292/087 (20150401) |
Current International
Class: |
B65D
43/16 (20060101); E05c 019/08 () |
Field of
Search: |
;292/DIG.38,DIG.53,DIG.42,246,80,87,88,89,248,250
;16/150,DIG.13,158 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Moore; Richard E.
Claims
I claim:
1. In a container having mating cover and body parts, a detachable
latch member formed of thermoplastic material in a one-piece
unitary construction comprising generally parallel mounting and
latching bar portions and a pair of generally parallel side leg
portions extending therebetween to provide a latching member of
generally rectangular configuration, said mounting bar portion
having a slot extending therethrough, means on one of said parts
for snap-fitted interlocking engagement with said slot of said
latch, a locking tab extending from said latching bar portion
toward said mounting bar portion, and means on the other of said
container parts releasably engaging said locking tab.
2. The combination as set forth in claim 1, wherein said
interlocking engagement means comprises an anchor bar projecting
outwardly from said one container part, said anchor bar having at
least one enlargement and a reduced width neck portion connecting
said enlargement to said one container part, said enlargement being
received in said slot of said latch in releasably snap through
engagement.
3. The combination as set forth in claim 2 wherein said neck
portion includes a taper and said slot is defined in part by at
least one surface complementary to said tapered neck portion and
leading to a shoulder, said enlargement snap-fitting past said
complementary surface into locking engagement with said
shoulder.
4. The combination as set forth in claim 1, wherein said
interlocking engagement means comprises an anchor bar projecting
outwardly from said one container part, said anchor bar having a
pair of laterally spaced-apart enlargements and a rib extending
between said enlargements, and reduced width shanks connecting said
enlargements to said one container part.
5. The combination as set forth in claim 4, wherein said shanks
have tapered surfaces from one end to the other thereof and said
slot is defined in part by surfaces complementary to said tapered
surfaces of said shanks.
6. The combination as set forth in claim 1 wherein said means
releasably engaging said locking tab comprises a beaded shoulder
formed integral with said other container part.
7. The combination as set forth in claim 1 wherein said side leg
portions and the outer faces of said mounting and latching bar
portions normally lie along a common plane of repose, and wherein
said locking tab extends in a second plane offset from and
generally parallel to said common plane, said latch member assuming
said plane of repose in latching position.
8. The combination set forth in claim 1, wherein said last-named
means includes a shouldered enlargement beneath which said locking
tab engages in the latched position of said member and abutment
means engaged by said mounting bar portion when said member is in
said latched position.
Description
BACKGROUND OF THE INVENTION
This invention relates generally to the container art, and more
particularly to a new and improved latch for securing a cover to a
container body in closed position.
The blow molding of separate container bodies and covers of a
double wall construction is known and is desirable from various
points of view. Generally, the cover is hinged along one side
thereof to the container body and the opposite side of the cover
and also the container body are provided with a latch for locking
the cover to the container body in a closed position. These latches
often are molded as an integral part of the cover or container body
or formed of plastic and bonded or otherwise fixedly secured
thereto as an integral part thereof. Such latches are repeatedly
flexed and deformed during latching and unlatching and are
subjected to recurring stresses with the result that they often
tear and are damaged to an extent such that they are no longer
suitable for the intended purpose. Because they form an integral
part of the cover or container body, the container must be
discarded along with the damaged latch.
It is sometimes desirable to cut away only a portion of the inner
shell of the double walled container bodies, thereby providing
access to the interior of the container body for storage or any
other purpose while making use of the remaining portion of the
inner shell as an article supporting shelf. This shelf tends to
flex and sag downwardly, particularly under the weight of articles
placed thereon, and because of its integral connection with the
container body sometimes tends to slightly distort the same out of
shape, all of which is undesirable.
SUMMARY OF THE INVENTION
Accordingly, the primary object of the present invention is to
provide a detachable latch construction which is particularly
suitable for blow-molded container parts and which can be readily
applied to and removed from the selected container part.
Another object of this invention is to provide the foregoing in a
latch and an associated mounting part which latter can be
conveniently fabricated during a blow-molding operation and which
can be readily interlocked in assembled relation.
A further object of the present invention is to provide a bracing
member for reinforcing and rigidifying the container body
construction which member can be conveniently fabricated during the
blow-molding operation.
In one aspect thereof, a plastic container of the present invention
is characterized by the provision of a detachable latch member
having a configurated slot adapted to receive a similarly
configurated anchor bar projecting from one of the container parts
for releasable snap through engagement therewith. The latch member
has a locking tab releasably engaging behind a shoulder formed
integral with the other container part. A brace member extends
between the bottom wall of the container body and a segmental
portion of the inner shell thereof to support and rigidify the
shelf formed thereby.
The foregoing and other objects, advantages and characterizing
features of the present invention will become clearly apparent from
the ensuing detailed description of an illustrative embodiment
there, taken together with the accompanying drawings wherein like
reference numerals denote like parts throughout the various
views.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
FIG. 1 is a top plane view of an illustrative container embodying
the present invention, in closed position;
FIG. 2 is a front elevational view of the container of FIG. 1;
FIG. 3 is a top plan view of the container body showing a
fragmentary portion of the cover in an open position;
FIG. 4 is a vertical sectional view, on an enlarged scale, taken
about on line 4--4 of FIG. 1, showing the means for reinforcing and
rigidifying the shelf of the container body;
FIG. 5 is a fragmentary front elevational view, on an enlarged
scale, of the latch mounting means and the latch engaging means of
this invention;
FIG. 6 is a rear elevational view, on an enlarged scale, of the
latch of the present invention;
FIG. 7 is a fragmentary vertical sectional view, on a further
enlarged scale, taken about on line 7--7 of FIG. 2; and
FIG. 8 is a similar view taken about on line 8--8 of FIG. 2.
DETAILED DESCRIPTION OF AN ILLUSTRATED EMBODIMENT
The illustrative container depicted in the accompanying drawings
comprises a base or body, generally designated 10, and a lid or
cover therefor, generally designated 12. Body 10 is formed of a
thermoplastic material blow-molded into the desired shape and
having a hollow, double-wall construction formed by an outer shell
comprising opposite end walls 14, a front wall 16, a rear wall 18
and a bottom wall 20, and an inner shell 22 initially extending
across the upper end of the outer shell in spaced relation thereto
except adjacent the edge portions thereof. Inner shell 22 is formed
to provide a recessed compartment as indicated at 24 (FIGS. 3 and
4), and can be otherwise compartmented, as desired, for receiving
variously shaped articles. After body 10 is removed from the mold,
a portion of inner shell 22 is cut-away in the illustrated
embodiment to provide an opening 26, leaving a cantilevered
segmental portion of inner shell 22 within body 10 to serve as an
integral tray or shelf. Opening 26 also provides access to the
interior of body 1.
Cover 12 also is formed of thermoplastic material blow-molded into
a hollow, double wall construction defined by an outer shell having
opposite end walls 28, a rear wall 30, a front wall 32 and a top
wall 34, and an inner shell extending across the outer shell in
spaced relation thereto except adjacent the edge portions thereof.
The cover inner shell has a top wall 36 formed to provide a series
of corrugations or ribs 38 extending substantially lengthwise
thereof except for a central, forward portion which is recessed as
at 40 in spaced relation to a recess 42 formed in top wall 34 of
the outer shell. The cover inner shell also has front and rear
walls 35, 37 and opposite end walls 39, and is surrounded by a
generally horizontal ledge 54 extend to the juncture with the outer
shelf. Ledge 54 can be stepped along the front and opposite ends of
the cover to fit within the upper end of body 10. Ribs 38 prevent
buckling of top wall 34 and also serve to reinforce and rigidify
inner shell 36. A suitable handle 44 is pivotally mounted within
recess 42 and can be swung out of the way into recess 42 when not
in use.
The outer shell of body 10 is formed to provide an outwardly offset
band 46, extending horizontally around body 10 adjacent the upper
end thereof and the juncture of the outer shell with inner shell
22. The inner shell is formed, adjacent its juncture with the outer
shell, to define an arcuate shoulder 48 (FIG. 4) slightly inwardly
recessed relative to the upper edge of band 46, and the lower end
of shoulder 48 terminates in a generally horizontal ledge 50 which
extends about the upper inner edge of body 10.
Cover 12 and body 10 are formed with integral, interfitting hinge
pin receiving portions of substantial strength. In the illustrated
embodiment, cover 12 is formed along its rear edge adjacent each
opposite end thereof with a pair of hinge extensions 52 formed
integrally therewith and which depend from ledge portion 54 of
cover 12. Extensions 52 are of generally U-shaped transverse
section defining channels which are closed at their opposite ends
by end walls 56 (FIG. 1) depending from ledge portions 54 and
formed integrally with cover 12. Extensions 52 thereby define
pockets which normally open upwardly.
Container body 10 is also provided, in the illustrated embodiment,
with a series of hinge pin receiving portions adjacent the opposite
ends thereof which receive the cover hinge extensions 52 in
interfitting relation. The body hinge portions comprise extensions
58 which are like extensions 52 but project rearwardly outwardly
from the upper edge of offset band 46 and provide pockets which
normally downwardly. Cover hinge extensions 52 and body hinge
extensions 58 are formed integral with cover 12 and body 10,
respectively, and with hinge pin bearing portions of increased
thickness in a blow-molding technique disclosed in detail in
copending application Ser. No. 9,529, filed Feb. 9, 1970 and
assigned to the same assignee as the instant application, reference
being made to said copending application for further details.
When cover 12 and body 10 are assembled, the cover hinge extensions
52 fit between the body hinge extentions 58, as clearly shown in
FIGS. 1 and 3. Holes are drilled or otherwise formed through the
end walls of each set of hinge extensions 52 and 58 and are
disposed in axial alignment for the reception of suitable hinge
pins 60. While a simple, ordinary nail can be used as the hinge
pin, with the pointed end facilitating passage of the pin through
the various aligned openings, it will be appreciated that simple
cylindrical stock of any suitable nature can be used, and indeed
the pin need not even be cylindrical.
A particular feature of the present invention resides in the
latching arrangement provided thereby. In the illustrated
embodiment, showing a heavy duty construction, there are a pair of
latches, generally designated 62, for releasably locking cover 12
to body 10 in closed position. Each latch 62 (FIGS. 6, 7 and 8) is
of a generally rectangular configuration formed as a unitary,
one-piece construction and includes a generally horizontal mounting
bar portion 64 having a pair of spaced, generally rectangular
openings 66 connected together by a central, elongated openings 68
of lesser width or height than openings 66 and forming therewith a
continuous slot, generally designated 70, extending through bar
portion 64. As shown in FIG. 8, the cross section of each opening
66 is defined in the forward portion thereof by spaced upper and
lower horizontal surfaces 72 and 74 forming right angles with
vertical surfaces 76 and 78 which terminate in opposed lip portions
80 and 82, respectively, defining a throat construction
therebetween. Surfaces 76, 78 provide shoulders for a purpose to be
described. A pair of opposed inclined surfaces 84 and 86 extend
from lip portions 80 and 82 rearwardly in a diverging relation to
the rear wall of bar portion 64.
In order to detachably secure latches 62 on cover 12, the latter is
provided with a pair of latch receiving extensions 88 formed
integral with cover 12 on the front peripheral surface of the outer
shell thereof opposite the hinged connections and adjacent ledge
portion 54. An extension 88 is provided for each latch, and each
extension is provided with a latch anchor bar, generally designated
90, projecting forwardly of cover 12 for interlocking engagement
with mounting bar slot 70 of latch 62. Latch anchor bar 90
comprises a pair of spaced, rectangularly shaped locking head
formations or enlargements 92 (FIG. 5) connected together by an
elongated rib 94 extending therebetween. As shown in FIG. 8, the
enlargements 92 are connected to the base of extension 88 by means
of reduced width neck portions or shanks 96 having opposed tapered
surfaces complementary to surfaces 84 and 86 of the mounting bar
portion 64 of latch 62. Head formations 92 are dimensioned to fit
within the forward portion of openings 66, with rib 94 fitting
within opening 68. The height of head formations 92 exceeds the
height of the throat (i.e., the spacing) between lips 80 and 82.
However the inherent resiliency of the platic material forming
latch 62 and latch anchor bar 90 permits the passage of head
formations 92 between lips 80, 82 and into the forward portion of
openings 66 with a snap-fit engagement, bar 64 resiliently yielding
and deforming to permit snap passage of enlargements 92 through the
restricted throats of openings 66. The tapered or inclined surfaces
84 and 86 of bar portion 64 can apart the mounting bar lips 80, 82,
thereby facilitating the insertion of anchor bar 90 through slot 70
of mounting bar 64. Once assembled, head formations 92 engage
against shoulders 76, 78 to preclude accidental separation of each
latch member from its anchor bar.
Mounting bar portion 64 is generally rectangular and relatively
thick in cross-section, having a pair of hollowed out portions or
cavities 98 extending inwardly of the rear wall thereof adjacent
opposite ends of bar portion 64 as shown in FIG. 6. A latching bail
of generally U-shape comprises a pair of side legs 100 depending
from opposite ends of bar portion 64 and joined at their lower
extremities by a horizontal latching bar portion 102 which has a
finger tab 104 depending centrally therefrom. Legs 100, bar 102 and
tab 104 are relatively thin, compared to the thickness of mounting
bar 64, and normally lie in a common plane which includes the front
face of mounting bar 64, being substantially coplanar therewith. A
generally U-shaped reinforcing bead 106 is formed on the rear side
of latch 62 integrally therewith and extends horizontally along
latching bar portion 102 and partially upwardly along sidelegs 100.
A locking tab 108 extends upwardly from the central portion of bead
106 and projects upwardly above latching bar 102 for snap-fit
engagement behind a beaded, latching shoulder 110 provided on the
container body as will be described. The front face of tab 108 is
substantially flush with the plane containing the rear face of legs
100.
The outwardly offset band 46 is discontinuous adjacent the latches,
having laterally spaced end walls 112 (FIGS. 2 and 5) and a
box-like enlargement 116 positioned centrally therebetween and
joined thereto by generally horizontal abutments 114 (FIG. 5). Each
enlargement 116 comprises a front wall 118 (FIG. 8) terminating at
its lower end in a bottom wall 120 extending to the upper portion
of front wall 16. Latching shoulder 110 is disposed beneath bottom
wall 120 adjacent the forward end thereof. A pair of opposite end
walls 123 complete the latching enlargement on body 10, which
enlargement and abutments are blow-molded with and as an integral
part of body 10.
Latch members 62 are readily snap-fitted in assembled relation on
their respective anchor bars 90, as previously described. With the
various parts assembled as shown in FIGS. 4, 7 and 8, it will be
seen that locking tab 108 engages behind latching shoulder 110,
securely locking cover 12 to body 10 in closed position. Any force
tending to move cover 12 upwardly, away from body 10 is effectively
resisted by engagement of locking tab 108 against bottom wall 120
and the direction of such force is such that it will not separate
latch member 62 from its anchor bar 90.
It is a feature of this invention that when latch members 62 are in
latched position, with tab 108 engaged behind shoulder 110, the
latching bail parts 100, 102 lie in their natural plane of repose,
whereby they are not under any stress except within that plane. The
rear face of shoulder 110 and the rear face of the latching bail
are coplanar or substantially so in the latched condition. Locking
tab 108 is snapped over latching shoulder 110 by flexing members
100, both to release and to latch the container cover 12. The latch
is flexed and bent only upon attachment to latch anchor bar 90 and
thereafter only during opening and closing of cover 12, and is not
otherwise stressed out of its plane of repose.
As a result, latch member 62 is assured a relatively long useful
life, assuming normal use thereof. While latch 62 is formed of a
suitable tear resistant material, such as polyethylene or
polypropylene having a long flex life, for example, a significant
advantage residing in the latch of this invention is that in the
event of excessive wear or damage thereto, it can be readily
removed and replaced by another latch member without having to
discard the entire cover. Both the latch and the latch engaging
shoulder are molded parts, the former being injection molded
whereby the dimensions thereof can be easily controlled through
proper mold design, and forming the latch as a separate member
permits it to be made from a different material and, if desired, in
a different color than either cover 12 or body 10.
It also is a feature of this invention that when latch member 62 is
engaged in latched position, the under surface of latch mounting
bar 64 seats firmly against the upper surface of abutment 114 on
opposite sides of enlargement 116 and in vertical alinement with
latching bail legs 100. This assures better control over the
latching dimension which now is determined by the accurately molded
latch member 62 and by the base casting used in molding body 10.
Legs 100 rest against and are supported by the front faces of
abutments 114 which are coplanar with the rear faces of legs 100,
when member 62 is in latched position. With this arrangement, the
latching dimension is controlled by direct engagement of the latch
against the body (i.e., bar 64 against abutment 114) instead of
relying upon proper fitting of the cover in its closed position. In
other words, the closed position of the cover now is determined by
the latch.
While a pair of latches are utilized in the specific container
illustrated in the drawings, it should be understood that only one
or any number of latches 62 may be employed, as desired and that
latch 62 is in no manner intended to be limited in use with the
specific container described and illustrated, but has utility in a
wide variety of applications wherein it is desired to releasably
latch one part to another.
Another significant feature of this invention is the provision of a
removable, reinforcing, brace member, generally designated 122
(FIG. 4), for reinforcing and adding rigidity to the cantilevered
inner shell 22 of body 10. Brace member 122 comprises a frame
having a pair of side legs 124 joined at their upper extremities by
an extension 126 extending therebetween. A wedge shaped embossment
128 projects laterally outwardly from the frame and comprises a
pair of right angularly related walls 130 and 132 and a pair of
inwardly converging side walls 133. Wall 130 extends from wall 132
to the lower end of the frame forming an acute angle therewith and
is provided with a plurality of longitudinal ribs 134 for adding
strength and rigidity to brace member 122.
In the formation of body 10, an inverted U-shaped recess or well
136 is formed in the outer shell of body 10 approximately midway
between the ends thereof by rear wall 18 and a bead or ridge 138 of
U-shaped configuration formed in bottom wall 20 immediately
adjacent rear wall 18. Since a portion of inner shell 22 is severed
and removed after the formation thereof, the remaining portion
tends to flex or bow downwardly toward bottom wall 20, particularly
when supporting articles in use. To preclude such deformation and
rigidly support shell 22, brace member 122 is inserted in body 10.
As shown in FIG. 4, the lower end of brace member 122 is placed in
the groove, or well defined by bead 138 and the extension end 126
of brace member 122 is fitted into engagement with a downwardly
opening groove 136 formed in the shelf portion of the inner shell
between wall 137 of compartment 122 and wall 139 defining one edge
of the opening through the inner shell. Thus, a strong, rigid
shelf, supported and reinforced by brace member 122, is provided in
container body 10 for the storage of various articles.
From the foregoing, it is apparent that the objects of the present
invention have been fully accomplished. As a result of this
invention an improved latch arrangement using a separately formed,
readily detachable and replaceable latch member is provided for
locking container parts in a closed position. In the event the
latch is damaged to render it useless, it can be easily replaced
without having to discard the container part to which it is
attached. By the provision of a brace member, the segmental portion
of the inner shell remaining, in the container body is adequately
reinforced to retain its shape and support weighted articles. The
container parts, including the latch and brace members, can be made
of any suitable thermoplastic material, such as high density
polyethylene, polypropylene, polyvinyl and elastomeric polyolefin,
which are given by way of example only.
Latch member 60 preferably is injection molded. Brace member 122
can be injection molded, but preferably is molded simultaneously
with the container body and cover by compression forming using
thermoplastic material severed from the parison as the mold
sections close.
A preferred embodiment of this invention having been disclosed and
described in detail, it is to be understood that this has been done
by way of illustration only.
* * * * *