Note: Descriptions are shown in the official language in which they were submitted.
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CONTAINER FOR TRANSPORTING HAZARDOUS SUBSTANCES
Field
This invention relates to containers for safely transporting liquid or pasty
hazardous
substances. More particularly, this invention relates to such containers that
have a safety
seal.
Background
Containers for the safe transport of liquid or pasty hazardous substances have
been known
for a long time. One thing that these containers have in common is that they
must be
sufficiently leak-proof to prevent any escape of the transported hazardous
substances.
Secondly, they must be equipped with a closure that ensures safe closing of
the container
even under extreme loads. In particular, containers of this kind and their
closures must
withstand loads that may occur also in the event of an accident, for example
falling of the
container from a certain height.
Containers of this kind known from the prior art include, in particular, pails
or drum-like
containers whose lids are screwed on firmly to form a screw closure. To secure
the closure,
metal clips may be provided additionally, which press the lid onto the
container or prevent
the screw closure from unscrewing. There are also closure systems where the
lid, after being
fitted onto the container, is appropriately flanged to make the arrangement
leak-proof.
Systems are furthermore known in which the lid or closure is bonded or welded,
or in which
additional sealing films are bonded or welded.
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The disadvantage common to all of these containers or closure systems is that
they are
complicated and difficult to handle; this is particularly problematic in view
of the need for
largely automated handling of such objects, including the closure process.
Summary
The object of this invention is thus to provide a leak-proof and securely
closable container
that is suitable for the transport of liquid or pasty hazardous substances,
both the production
and handling of said container being uncomplicated and effective.
The container of the invention, which is preferably configured as a pail or in
drum-like
form, has a lid for closing the container, said lid having a receiving area in
which, in the
closed state, the lip of the container opening engages and is held there. In
so far, the
container of the invention is based on known containers.
Compared to the prior art, however, this invention pursues a completely
different approach
to solve the problem at hand. The container of the invention is based on the
realization that
by providing positively interconnectable catch members and correspondingly
interacting
sealing surfaces, it is possible to close a container securely and tightly.
The use of positive
connections formed by catch members and of appropriate sealing surfaces
ensures that both
handling and production are kept simple. Effective use of the container is
thus ensured.
The positive connections formed by catch members are preferably configured
such that the
lid of the container can only be loosened if at least part of the lid or part
of the container is
destroyed. The user thus has a verifiable first-opener guarantee, since only a
container that
has never been opened is undamaged, whereas a container that has already been
opened will
have a damaged lid or be damaged itself.
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According to a preferred embodiment of the container, the receiving area of
the lid and the
lip of the container opening, which engage on closure of the container, i.e.
the catch
members that form the positive connection, and the sealing surfaces are
engineered such that
putting on of the lid, i.e. closing of the container, is effected by way of
translational
movement of the lid relative to the container. It is particularly advantageous
if the lid is
simply pushed onto or clipped onto the container from above. This permits
automatic
closing of the container by a machine, since a translational movement or
pushing or clipping
on operations can easily be performed on a machine.
According to a preferred embodiment, at least two, preferably three or more
pairs of catch
members are provided in the receiving area of the lid and at the lip of the
container opening,
since a plurality of catch-member pairs makes it possible to secure the lid at
several points
and thus helps to close the container securely. The term "catch-member pair"
does not refer
here to just two catch members that lock positively together, but may also
refer to a large
number of catch members, which, however, on account of their similar
configuration and
identical mode of action, are deemed to be just one catch-member pair. This
applies, for
example, to catch members formed simply by a sub-division.
According to a preferred embodiment of the container, the at least two,
preferably three or
more catch-member pairs are engineered such that at least one of these catch-
member pairs
is configured differently to the other catch-member pairs in such manner that
the movement
necessary to disengage the catch-member pair differs from that for the other
catch-member
pairs. This means that not all the catch-member pairs can be disengaged at
once by way of a
single movement of part of the lid, that is, of the receiving area of the lid,
or of the lip of the
container opening. On the contrary, the different movements required to
disengage the
catch-member pairs in their entirety ensure that a complex movement is
necessary. It has
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proved particularly useful to provide at least two kinds of catch-member
pairs, which
require opposing movements to disengage the catch. A particularly interesting
approach
here, for example, is to necessitate a portion of the receiving area to move
both outwards
and inwards for purposes of opening. This measure, in particular, thus goes
beyond that of
the need for different, in particular opposing, movements to disengage
circumferential catch
members located on opposite sides. Here, it is much rather different catch-
member pairs that
are meant, which are located close by each other, for example, one above the
other.
The provision of different kinds of catch-member pairs that differ in the
different type of
movement needed to disengage the catch has the additional advantage that in
this way, with
the members that form the positive connection, an adequate clamping action may
also be
generated for the sealing surfaces provided likewise in the receiving area of
the lid and at
the lip of the container opening. Even if the pressure of the sealing surfaces
against each
other is already effected by appropriate dimensioning of the lid and the
container opening,
the provision of different kinds of catch-member pairs, as described above,
ensures an
additional contact pressure that can be reliably upheld in many stress
situations.
In addition to separately located sealing surfaces, it is of advantage to
provide matching
sealing surfaces on the catch members forming the positive connection, since,
particularly
where different kinds of catch-member pairs are used that necessitate
movements in
different directions in order to disengage the catch, mutual keying can be
effected which
results in the positively-locking catch members pressing against each other to
a certain
extent and thus forming sealing surfaces.
According to a preferred embodiment, additional seals may be provided in the
receiving
area of the lid and/or in the lip area of the container, particularly in the
form of inserted or
injected gaskets.
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To realize the first-opening guarantee, as it is called, it may also be
advantageous to provide
a predetermined partition location in the receiving area of the lid and/or in
the lip area of the
container opening in order that those areas which guarantee a safe and
unreleasable
connection can be detached easily. In particular, it is of advantage here to
provide -in the
receiving area of the lid or on the lip of the container opening -a
predetermined partition
location which results in that part of the receiving area and/or of the lip
being detached that
has the differently functioning catch-member pair(s), as this kind of catch-
member pair, in
particular, may prevent the positive connection from being released.
According to a preferred embodiment, the cross-section of the receiving area
of the lid is
essentially V -shaped, the receiving area being open at the bottom in order to
accommodate,
from there, the lip of the container opening. The legs of the V-shaped
receiving area enclose
the lip of the container opening and hold it firmly, in positive-locking
manner, by means of
catch members. The sealing surfaces, meanwhile, are pressed firmly together,
thus ensuring
the sealing effect.
While it is of course possible to provide a large number of different
combinations of detent
hooks, latches, snap-in grooves etc., and appropriately configured sealing
surfaces, the
preferred embodiment of this invention has, in the V-shaped receiving area
formed by an
outer and an inner leg, two latches or detent hooks on the inside of the outer
leg, said two
latches or detent hooks interacting with two latches on the outside of the lip
of the container
opening. On its outside, the outer leg of the V-shaped receiving area has, in
addition, a
further detent hook that interacts with an undercut in the lip of the
container opening, said
undercut being provided in a double-walled portion of the lip, on the outer
arm of the lip. By
locating detent hooks or latches both on the inside and on the outside of the
outer leg of the
U-shaped receiving area, and configuring corresponding undercuts or catch
members on the
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lip area of the container opening, two different kinds of catch-member pairs
are formed
which differ in that the catch formed by the one kind of catch-member pair can
be released
by moving the outer leg outwards, whereas to release the catch formed by the
other kind of
catch-member pair, the outer leg must be moved inwards.
This simple configuration of catch-member pairs ensures, for one thing, that
the lid can
easily be put onto the container by a vertical downward movement. For another,
this triple
locking system ensures that the lid is fitted securely on the container. The
different kind of
catch-member pairs with the opposing opening movements ensures additionally
that the lid
cannot be removed without incurring damage.
To permit easy opening of the container without the use of any particular
specialty tools,
and to ensure that the lid is easily put on, a constriction is engineered in
the outer leg of the
U-shaped receiving area, so that in this area an integral hinge, or film
hinge, forms, which
constitutes a lower segment of the outer leg. One effect of this film hinge is
that the lower
segment of the outer leg can perform the movements necessary to get past the
latches or
detent hooks and the undercuts during closure of the container, that is, when
the lid is put
on. The film hinge, i.e. the constriction, additionally offers the possibility
of detaching the
lower segment by simply cutting along the film hinge with a cutting tool such
as a knife.
Since the receiving-area catch members for two different catch-member pairs
are preferably
provided in the lower segment of the outer leg, only one catch remains after
detachment of
the lower segment. This last catch may be released via a slight movement of
the outer leg of
the receiving area. This single remaining catch permits continued use and
renewed closure
of the container after it has first been opened, although it does not provide
for secure closure
with a first-opening guarantee. This single remaining catch also permits
continued use and
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re-closure of the container after it has first been opened, although secure
closure with a
first-opening guarantee is no longer ensured.
To permit uniform closure of the container, it is preferable if the catch
members or
catch-member pairs are located circumferentially around the container opening
and lid;
interruption or sub-division of a catch member by recesses, lands, etc. may
result in the
formation of a corresponding plurality of catch members, although, as defined
in this
invention, the purpose of uniform closure and treatment as one catch member or
two catch
members making up one catch-member pair is upheld.
Thanks to the measures described above, standard materials can be used for the
container of
the invention, without the need for special measures. Polyolefin-based
plastics are preferred,
in particular polyethylene and polypropylene. The sealing aids preferably used
in addition
need not fulfill any special requirements either regarding the choice of
material, although,
depending on the application in question, special requirements regarding the
choice of
material may exist. Alone the dimensioning of the components, for example the
wall
thicknesses, must be adjusted to suit the application in order to withstand
the necessary
forces also in the case of exceptional loads, caused, for example, by
accidents.
Brief Description of the Drawings
Further advantages, characteristics and features of this invention become
clear from the
following detailed description of an embodiment and the attached drawings. The
figures are
purely schematic.
Fig. 1 shows a partially cut-away side view of a container with its lid on;
Fig. 2 shows details of Figure 1 at various stages of closure (Figs, 2a, 2b
and 2c);
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Fig. 3 shows a cross-sectional view along the line D -D of Fig. 2b;
Fig. 4 shows a cross-sectional view along the line D -D of Fig. 2c;
Fig. 5 shows a perspective view of the container with its lid on;
Fig. 6 shows a perspective partial view of the container with its lid off;
Fig. 7 shows two containers stacked one inside the other;
Fig. 8 shows a transverse view (Fig. 8a) of two lids stacked on top of the
other, and details
(Fig. 8b) of Fig. 8a; and
Fig. 9 shows a top view of the container lid.
Detailed Description
Fig. 1 shows a partially cut-away side view of a closed container 1 according
to the
invention, that is, with its lid 2 on. In the embodiment shown, the container
1 is in the form
of a pail to which, to facilitate carrying, a rotatable handle 27 is attached.
As can be seen in the partially cut-away section of Fig. 1, the container 1
has a slightly
inward-arching bottom 30 that has supporting feet 31 at its outer edge; there
is thus a small
space between the bottom 30 and the surface on which the pail stands. The
container 1
furthermore has a slightly conical, albeit essentially cylindrical, outer
shape, so that empty
containers can be nested.
Figures 2a to 2c show details of the cutaway section, with the receiving area
4 and the lip 3
of the container opening, at various stages of closure of the container 1.
In Figure 2a, the container is still completely open; the lid 2 is resting
lightly on the
container opening, that is, on the lip 3 of the container opening. As is
clearly evident in this
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detailed view, the receiving area 4 at the periphery of the lid 2 is
essentially V -shaped, with
the receiving area open at the bottom so as to accommodate from there the
element 9 of the
lip 3 of the container opening. The receiving area 4 thus has two legs 5 and
6, namely an
outer leg 5 and an inner leg 6, which are interconnected in the connecting
area 7 at the foot
of the U. The inner part of the lid 2 is connected via the lip connection 22
with the receiving
area 4; the lip connection 22 forms an opposing V with the inner leg 6 of the
receiving area
4, so that the inner part 32 of the lid 2 is located at the level of the upper
part of the
receiving area 4. The receiving area 4 in the embodiment shown forms a
circumferential
stacking edge, so that closed containers 1 can be stacked one above the other.
Any shifting
relative to one another is largely prevented by the receiving area 4.
On the inside of the outer leg 5 of the receiving area 4, two latches 12 and
13 are provided,
while on the outside of the outer leg 5, almost at the bottom thereof, a
detent hook 14 is
engineered. The latches 12 and 13 and the detent hook 14 are spaced at
approximately equal
distances along the outer leg 5. In the immediate vicinity of the latch 13, in
the area between
the latch 12 and the latch 13, a constriction is provided in the outer leg 5
of the V-shaped
receiving area 4, so that an integral hinge 15, or film hinge 15, forms; at
the same time, on
the inside of the outer leg 15, immediately adjacent to the latch 13, a groove
20 is
engineered.
The side of the inner leg 6 that is opposite to the inside of the outer leg 5
is engineered as a
smooth sealing surface; this sealing surface is angled somewhat relative to
the vertical.
Directly in the area 7 connecting the legs 5 and 6 of the U-shaped receiving
area 4, in the
curvature 29 of the U-shaped receiving area, space is provided for
accommodating a gasket
that is not shown.
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At its container opening, container 1 has a lip that is double-walled in the
lower portion. In
this lower portion of the lip 3 of the container 1 there is, in addition to
the inner element 9,
also an outer element 8 that forms the double wall. The lip 3 of the container
1 is thus made
up of two sections, namely an upper, first section in which the lip 3
comprises the element 9
and is single-walled, and a lower, second section in which the lip 3 comprises
the outer
element 8 and the inner element 9, making it double-walled. In the first,
upper section of the
lip 3 of the container 1, on the outside of the element 9, two detent hooks 10
and 11 are
provided which, in cross-section, are configured essentially as almost
triangular projections.
The second, lower section of the lip 3 of the container 1 has openings 25 at
the top. At the
same time, the outer element 8 with the edge of the opening 25 forms an
undercut 21.
On the inside of the inner element 9 of the lip 3 of the container 1, a
smooth, planar sealing
surface 17 is engineered, which matches the sealing surface 16 of the
receiving area 4 of the
lid.
The closing process is shown in Figs. 2b and 2c. Figure 2b shows that on
closure of the
container I with the lid 2, the element 9 is inserted into the U-shaped
receiving area 4, with
the latch 13 first sliding past the detent hook 10, while the lower end of the
outer leg 5 with
the detent hook 14 is introduced into the opening 25 of the double-walled
section of the lip 3
of the container 1.
As the container 1 is closed further with the lid 2, as shown in Fig. 2c, the
latch 12 also
slides past the detent hook 10, and the latch 13 past the second detent hook
11. The latches
12 and 13 and the detent hooks 10 and 11 are configured such that they have
complementary
inclined surfaces which permit the latches to slide past the hooks in the
direction of closure,
whereas they are prevented from sliding back again by the positive-locking
catch. At the
same time, on complete closure, the lower part of the outer leg 5 is
accommodated
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completely in the double-walled section of the lip 3, the detent hook 14
coming to rest
beneath the undercut 21. It becomes evident here that on closure, the lower
segment 33 of
the outer leg 5 is on the one hand pressed outwards by the detent hook 11,
whereas, on the
other hand, the lower segment 33 of the outer leg 5 has to be bent inwards by
the detent
hook 14 in order for it to be inserted into the opening 25 of the double-
walled lip 3. This is
made possible, in particular, also by the configuration of the film hinge 15,
which permits a
different movement of the lower segment 33 depending on the stage of closing
with the lid
2.
In the completely closed state, it is evident that for one, the latches 12 and
13 form positive
connections with the detent hooks 10 and 11, while for another, the detent
hook 14 forms a
positive connection with the undercut 21. To release all three catch-member
pairs, it would
be necessary to move the outer leg 5 outwards to disengage the catch-member
pairs 12 and
and 11 and 13, while an inward movement would be necessary to disengage the
catch-member pair 14 and 21. As a result of the inclined surface provided by
latch 13, which
is supported on the detent hook 11, the catch effect of the catch-member pair
14 and 21 is
further reinforced, as a lever effect acts in the direction of the catch
position. It is therefore
impossible to release the catch mechanism without destroying the receiving
area 4, i.e.
without cutting or detaching the lower segment 33 along the film hinge 15.
Only when the
lower segment 33 has been detached by cutting along the film hinge can the
still-remaining
catch formed by catch-member pair 12 and 10 be released. This has the added
advantage that
after the container has been opened the first time, which is visible to
everyone due to the
lower segment 33 remaining in the double-walled section of the lip, the
container is still
suitable for continued use and can be closed again.
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Besides the formation of the catch-member pairs, a seal is generated on
closure of the
container due to the sealing surfaces 16 and 17 coming into contact, in
particular, being
squeezed together by appropriate adjustment of the dimensions of the lid 2 to
those of the
container 1 or the lip 3 of the container, and to the appropriate
configuration of the catch
mechanism between the receiving area 4 and the lip 3. In addition, the catch-
member pairs,
in particular the catch-member pair 12 and 10, also press sealing surfaces
together, in this
case the sealing surfaces 18 and 19, as shown in Fig. 2c. In the curvature
zone 29 of the
u-shaped receiving area an additional gasket that is not shown may be
included, which is
pressed by the upper end of element 9 against the connecting area 7 of the
receiving area 4,
thus producing an additional sealing effect.
As is also evident from Fig. 2c, the positive connection formed by the catch-
member pair
13, 11 is further reinforced by a groove 20 engineered on the inside at the
film hinge 15, into
which groove the detent hook 11 can engage additionally. Figures 3 and 4 show,
in cross-
section, details from Figs. 2d and 2c, in each case along the line D-D.
Figures 3 and 4 show
how the element 9 engages between the outer leg 5 and the inner leg 6 on
closure of the
container 1. The cut views make it clear that both between the outer element 8
and the inner
element 9 of the lip 3 and between the inner leg 6 and the lip connection 22
of the lid 2,
partitions 23 and reinforcing walls 24 are provided, so that the second,
lower, double-walled
section of the lip 3 has openings 25 at the top that are essentially
rectangular in cross-
section. The lower area of the outer leg 5 is accordingly provided with
complementary
recesses into which the partitions 23 can engage in the closed state.
Figures 3 and 4, like Figure 2c, show part of the handle 27, which is likewise
hinged in the
double-walled portion of the lip 3.
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Fig. 5 shows a perspective view of the container 1 with its lid 2 on it. This
perspective view
shows especially well how the handle 27 is rotatably hinged to the double-
walled portion of
the lip 3, in particular to the outer element 8.
The partitions 23, the reinforcing walls 24 and the openings 25 can also be
seen very clearly
in this projection. Figure 5 also shows the configuration of the stacking
supports 26, which
are located on the outside of the container 1, underneath the lip 3, in the
vicinity of the
hinging points for the handle 27. Figure 7 shows more clearly how the stacking
supports
work.
The lid 2 also has a pull means 28 attached to it, with which the lid 2 may be
removed after
the lower segment 33 of the outer leg 5 of the receiving area 4 (as shown
above) has been
detached. Figure 6 likewise shows a perspective view of part of the container
1 and of a lid 2
which has been removed therefrom. It is additionally evident from this
projection that the
outer leg 5 of the receiving area 4, at the lower end of which leg the detent
hook 14 is
provided, has a plurality of recesses 34 so that the outer leg 5 can engage
the openings 25
and the partitions 23 have room in the area of the recesses 34.
Figure 7 shows, in a partially cut-away side view, two containers 1 and 1'
stacked one inside
the other. It becomes clear here how the stacking supports 26 and 26' work,
which, when the
containers are nested, rest on the upper edge of the element 9. This prevents
the nested pails
from jamming and ensures a defined load distribution. The side view
illustrated in Figure 7
also shows clearly that the detent hooks 10 and 11 are engineered as
circumferential ridges
on the lip 3, that is, on the element 9.
As is evident from Figures 8a and 8b, not only the containers can be nested,
but also the
lids, as shown in Figure 8a. As illustrated in the detailed drawing of Figure
8b, the
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connecting area 7 of the receiving area 4 forms a circumferential stacking rim
into which the
lower end of the inner leg 6 of the lid 2' positioned above can engage. In the
cross-sectional
view illustrated in Figures 8a and 8b, however, a reinforcing wall 23 prevents
the inner leg 6
from being clearly apparent. The outer leg 5 is dimensioned such that the
lower end of the
leg 5 with the detent hook 14 is somewhat shorter than the lower end of the
inner leg 6, so
that the outer leg 5 ends above the connecting area 7 of a lid 2 positioned
underneath.
Figure 9 shows, in a top view of the lid 2, the uniform subdivision of the
perimeter of the lid
2 with the receiving area 4 by the reinforcing walls 24 and the recesses 34
and detent hooks
14. Although, of course, a large number of detent hooks are formed around the
perimeter by
the recesses 34, this plurality of detent hooks 14 is to be understood for the
purpose of this
application as one catch member, since, in particular, all the detent hooks 14
interact with
the circumferential undercut 21 and therefore form one catch-member pair. By
analogy, of
course, and in the meaning of the term as it is used here, one catch-member
pair can also be
formed from a large number of detent hooks and latches.
