[0001] This invention relates to the securement of lids to containers, particularly containers
such as paint cans.
[0002] Various methods are known for securing lever lids to containers having a lever ring.
GB-A-2096107 describes a clip for securing a lever lid to a lever ring of a container,
where the clip comprises a moulded or extruded element or elements of plastics material
which are applied to the container in a generally downwardly vertical direction such
that the inherent resilience permits arm members of the clip to engage substantially
simultaneously with associated surfaces of the lever ring and/or the lever lid. By
this means the clip, although firmly securing the lid to the ring, can easily be detached
therefrom without the need for special tools.
[0003] EP-A-0334514 describes a lid-retaining collar which comprises a generally annular
ring which has a radial slit therein so that the collar can more easily be parted
from the can. The collar has a peripheral skirt portion with a snap-fit bead which
engages below the double seam between the lever ring and the can body.
[0004] In these and other lid-retaining devices the major problem is maintaining a complete
seal against leakage of the contents if the can is dropped or otherwise subjected
to impact or pressure. Particularly for cans which are used to contain flammable liquids
there are specific standards which must be met. With overclo- sures of the types referred
to above, leakage of the contents can still occur if for example the can is dropped
in a particular attitude.
[0005] It is an object of the present invention to provide an improved can closure which
is more resistant to leakage.
[0006] In accordance with one aspect of the invention there is provided a container having
a cylindrical side wall, a lever ring secured to the upper margin of the side wall,
a lid fitted into the lever ring, a circumferential recess between the lever ring
and the lid, a circumferential groove in the lid adjacent to the radially outer edge
thereof, and an overclosure clip fitted to the lever ring and lid and extending around
substantially the whole circumference of the container, wherein the clip has three
depending portions engageable with the lever ring and/or lid, characterised in that
the radially outermost portion of the clip engages below a lip on the lever ring and
the two inner portions are each a tight resilient fit in said circumferential recess
and said circumferential groove respectively.
[0007] The clip preferably includes a circumferential cushioning ring outwardly of the lever
ring.
[0008] In a preferred embodiment the clip is provided with a plurality of slots equispaced
circumferentially around the clip from the radially inner margin of the clip outwards
to create a plurality of radially inwardly projecting tongues.
[0009] It is an important preferred feature of the invention that the outer wall of the
container lid is recessed and carries sealing means engageable between the lid wall
and a facing surface of the lever ring.
[0010] In accordance with another aspect of the invention there is provided an overclosure
clip for a container, comprising a strip having three depending portions engageable
with a lever ring and/or lid of the container, characterised in that the clip includes
a cushioning ring which in use lies radially outwardly of the outermost of the three
depending portions.
[0011] In accordance with another aspect of the invention there is provided a container
having a cylindrical side wall, a lever ring secured to the upper margin of the side
wall, a lid fitted into the lever ring, a circumferential recess between the lever
ring and the lid, a circumferential groove in the lid adjacent to the radially outer
edge thereof, and an overclosure clip fitted to the lever ring and lid and extending
around substantially the whole circumference of the container, wherein the clip has
three depending portions engageable with the lever ring and/or lid, characterised
in that the outer wait of the container lid is recessed and carries sealing means
engageable between the lid wall and a facing surface of the lever ring.
[0012] In order that the invention may be more fully understood, one presently preferred
embodiment of can closure in accordance with the invention will now be described by
way of example and with reference to the accompanying drawings, in which:
Fig. 1 is a schematic cross-sectional view through the portion of a can where the
can wall, lever ring and can lid meet;
Fig. 2 is a cross-sectional view, on an enlarged scale, through a securing clip adapted
to be fitted to the can shown in Fig. 1; and,
Fig. 3 shows a can lid modified in accordance with the invention to include a circumferential
seal and for use in combination with the clip of Fig.2.
[0013] Referring first to Fig. 1, there is shown part of a cylindrical can wall 10 having
a lever ring 12 secured thereto by a seaming operation which defines the periphery
of the can. As shown, the lever ring 12 has a lip 14 outwardly of the cylindrical
can wall. The lever ring 12 has an inturned portion radially inwardly of the cylindrical
wall 10 and which defines a circumferential recess 16. A can lid, indicated generally
at 18, is a socket fit within the lever ring 12 and has a circumferential lip 19 which
overlies the inner portion of the lever ring 12 and thus faces the recess 16. The
lid 18 includes a circumferential pocket 20.
[0014] As shown in Fig. 2, an overclosure or clip, indicated generally at 22, is designed
and shaped to fit over and into the can rim as shown in Fig. 1. The clip 22 comprises
a vertically extending skirt 24 which has an inwardly and upwardly directed tongue
26 which is adapted to engage below the lip 14 on the lever ring 12. The clip 22 has
an arm portion extending inwardly from the skirt 24 and adapted to make contact both
with the recess 16 and with the pocket 20. A protuberance 28 extending downwardly
from the clip is designed to seat resiliently within the circumferential recess 16.
The radially most inward portion 30 of the clip is designed to seat resiliently within
the circumferential pocket 20. The portion 30 has two ribs 31 and 32 which engage
the circumferentially innerface 33 of the pocket 20 and a surface 34 which engages
the circumferentially outer face 35 of the pocket 20. In contrast to the inner arm
member of the clip shown in GB-A-2096107, the portion 30 of the clip 22 is a tight,
resilient fit within the circumferential pocket 20. By making the protuberance 28
a tight resilient fit within the recess 16 and by making the portion 30 a tight resilient
fit within the circumferential pocket 20, allied with the engagement of the tongue
26 with the lip 14, the clip 22 is located fixedly in place when positioned on the
can and prevents relative movement of the component parts, particularly in the direction
at right-angles to the longitudinal axis of the can.
[0015] The clip 22 as shown in Fig. 2 includes an outer circumferential cushioning ring
36 to aid in absorbing impacts if the can is dropped on its rim. The cushioning ring
36 is preferably tubular and may be made of the same material or a different material
from that of the rest of the clip 22. In one preferred embodiment of the invention
the cushioning ring 36 is made of a flexible PVC material, whereas the remainder of
the clip is made of a high impact PVC material. The clip 22 is desirably extruded
and the cushioning ring 36 and the remainder of the clip can be co-extruded, with
the cushioning ring keyed to t he basic part of t he clip in the extrusion process.
It is also to be noted that the clip 22 is shaped so that the clip is of substantially
constant thickness throughout, i.e. the thickness of the skirt 24 and of the radially
inwardly projecting arm and of the cushioning ring 36 are all of substantially the
same dimension. This assists the extrusion of the clip so that one does not get areas
or zones which are of different temperature to others.
[0016] Although not shown in the drawings, the radially inwardly projecting arm portion
of the clip is provided with a plurality of slots spaced circumferentially around
the arcuate clip at equal intervals. These may be saw cuts through the thickness of
the arm in order to create a plurality of radially inwardly projecting tongues. These
slots in the clip preferably extend from the ribs 31 and 32 to approximately the position
indicated by the arrowAin Fig. 2. This gives the individual tongues a degree of resilience
which enables them more easily to locate within the recesses 16 and 20. It also assists
in the fitting of the clip by enabling it to be pushed on to the can, instead of having
to be hammered on.
[0017] In order to aid the sealing of the can, in combination with the clip 22, the can
lid 18, as shown in Fig. 3, is provided with auxiliary sealing means. The outer wall
38 of the can lid 18 is provided with a circumferential groove 40 which serves as
a locator for an O-ring seal 42. In one preferred embodiment of the invention the
O-ring seal 42 has a diameter of approximately 1.58 mm (1/16th inch) and the distance
x by which the O-ring seal projects beyond the surface of the lid wall 38 is between
0.125 mm (0.005 inch) and 0.25 mm (0.010 inch). However, these dimensions are given
by way of example only. The use of this O-ring seal 42 in combination with the clip
22 provides a double mechanism by means of which the can is securely sealed against
leakage.
1. A container having a cylindrical side wall (10), a lever ring (12) secured to the
upper margin of the side wall, a lid (18) fitted into the lever ring, a circumferential
recess (16) between the lever ring and the lid, a circumferential groove (20) in the
lid (18) adjacent to the radially outer edge thereof, and an overclosure clip (22)
fitted to the lever ring (12) and lid (18) and extending around substantially the
whole circumference of the container, wherein the clip (22) has three depending portions
(24, 28, 30) engageable with the lever ring and/or lid, characterised in that the
radially outermost portion (24) of the clip engages below a lip (14) on the lever
ring (12) and the two inner portions (28, 30) are each a tight resilient fit in said
circumferential recess (16) and said circumferential groove (20) respectively.
2. A container as claimed in claim 1, characterised in that the innermost portion
(30) of the clip (22) has two spaced ribs (31, 32) in engagement with the circumferentially
innerface (33) of the groove (20) and an intermediate web in engagementwith the circumferentially
outer face (35) of the groove (20).
3. A container as claimed in claim 1 or 2, characterised in that the clip includes
a circumferential cushioning ring (36) outwardly of the lever ring (12).
4. A container as claimed in claim 3, characterised in that the cushioning ring (36)
is tubular.
5. A container as claimed in claim 3 or 4, characterised in that the cushioning ring
(36) is of a flexible plastics material and the remainder of the clip is of a high
impact plastics material.
6. A container as claimed in claim 5, characterised in that the cushioning ring (36)
and the remainder of the clip are co-extruded.
7. A container as claimed in any preceding claim, characterised in that the outermost
depending portion (24) comprises a skirt having an inwardly and upwardly directed
tongue (26) in engagement with the lip (14) on the lever ring.
8. A container as claimed in any preceding claim, characterised in that the outer
wall (38) of the container lid (18) is recessed and carries sealing means (42) engageable
between the lid wall (38) and a facing surface of the lever ring (12).
9. A container as claimed in any preceding claim, characterised in that the clip is
provided with a plurality of slots equispaced circumferentially around the clip from
the radially inner margin of the clip outwards to create a plurality of radially inwardly
projecting tongues.
10. An overclosure clip for a container, comprising a strip having three depending
portions (24, 28, 30) engageable with a lever ring and/or lid of the container, characterised
in that the clip includes a cushioning ring (36) which in use lies radially outwardly
of the outermost (24) of the three depending portions.
11. Aclip as claimed in claim 10, characterised in that the cushioning ring (36) is
tubular and of flexible plastics material co-extruded with the remainder of the strip.
12. A container having a cylindrical side wall (10), a lever ring (12) secured to
the upper margin of the side wall, a lid (18) fitted into the lever ring, a circumferential
recess (16) between the lever ring and the lid, a circumferential groove (20) in the
lid (18) adjacent to the radially outer edge thereof, and an overclosure clip (22)
fitted to the lever ring (12) and lid (18) and extending around substantially the
whole circumference of the container, wherein the clip (22) has three depending portions
(24, 28, 30) engageable with the lever ring and/orlid, characterised in thatthe outer
wall (38) of the container lid (18) is recessed and carries sealing means (42) engageable
between the lid wall (38) and a facing surface of the lever ring (12).
13. A container as claimed in claim 12, characterised in that the sealing means comprises
an O-ring (42) projecting beyond the surface of the lid wall (38) by between 0.125
mm and 0.25 mm.