Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02426713 2006-01-10
1
Cup-shaped Receptacle and Lid
The present invention relates to a cup-shaped receptacle and to a lid for such
a
receptacle.
Of the clip-on plastic lid on the cup-shaped receptacle in US 5,253,781 A, the
outer
surface of the outer leg wall of the lid recess extends downwards just
slightly beyond
the height position of the constriction. The cone angle and the outer diameter
of the
outer surface are matched with the cone angle and the inner diameter of the
receptacle wall such that outer surface does not get in significant contact
with the
receptacle wall even when the bead of the receptacle, which is implemented as
a
curled rim, fully is seated on the clamping groove. Due to the comparatively
short
outer surface and the large radial dimension of the U-web of the lid recess,
the
clamping groove tilts inwards during the clip-on movement; this hinders the
bead to
smoothly move over the whole circumferential length past the constriction. It
is
necessary to first manually centre the lid with the clamping groove neatly on
the bead
and then to clip on the lid by pressure directly acting on the upper wall of
the clamping
groove with a sliding rotating movement of the hand. This clip on action is
troublesome, time-consuming and increases the risk that the bead does not
properly
snap into the clamping groove at some locations along the circumference of the
cup
opening. This has the effect that liquid may leak through when the full cup is
tilted.
The lid easily pops off inadvertently if the full receptacle falls over,
because the cup
opening region easily gets deformed radially.
It is an object of the present invention to provide a receptacle as well as a
lid which is
suitable for said receptacle, by means of which an easy clip-on action of the
lid can be
achieved, even by unskilled persons, such that the clipped on lid provides
leakage-
proofness and hardly pops off when the full cup falls over. Even though the
invention
intends to achieve a high lid holding force and perfect tightness, the lid
ought to be
clipped on easily.
According to the present invention, there is provided a cup-shaped receptacle
(C)
provided with a plastic material clip-on lid (D), an opening area (9) of the
receptacle
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2
(C) being delimited by an upwardly and outwardly tapering conical receptacle
wall (7)
and an outwardly projecting bead (10), the lid (D) being formed with a
peripheral
clamping groove (1) which is open on a lower surface of the lid for receiving
therein
the bead (10), the clamping groove (1) having at an outer lower end region an
elastically expandable constriction (14) and at an inner side a cylindrical or
conical
outer surface (6) of an outer leg wall (4) of a circumferentially extending
lid recess (V)
of U-shaped cross-section, a U-web (22) of the lid recess (V) being located
below the
height position of the constriction (14), an inner leg wall (23) of the lid
recess (V) being
part of a dome wall of a dome (2) having a dome top wall (5) located above the
constriction and the clamping groove, respectively, characterised in that the
lid recess
(V) is formed with such a depth to extend downwards beyond the height position
of
the constriction (14) and has an outer diameter (D1) at the outer surface (6)
at the
elevation of the constriction (14) adapted to an inner diameter (D7) of the
receptacle
wall (7) at the bead (10) such that during an easy clip-on operation of the
lid (D) the lid
recess (V) outer surface (6) functions as a lid centering and guide projection
(K) co-
operating by sliding contact with the receptacle wall (7) at least while the
bead (10)
moves past the constriction (14) into the clamping groove (1), when downwardly
directed clip-on pressure (R) mainly is applied to the dome (2), the cup-
shaped
receptacle (C) being also characterized in that the outer surface (6) extends
downwards beyond a height position of the construction (14) by a length (L1)
which is
greater than a height (L) of the clamping groove (1).
According to the present invention, there is also provided a lid (D) of
plastic material
for a receptacle (C) having an exterior bead (10) in an opening area (9), the
lid (D)
being provided with a peripheral clamping groove (1), which is open on a lower
surface of the lid for receiving therein the bead (10), the clamping groove
(1) being
continued at an outer lower end thereof by an elastically expandable
constriction (14)
and at an inner lower end thereof by a cylindrical or conical outer surface
(6) of an
outer leg wall (4) of a circumferentially extending lid recess (V) of
substantially U-
shaped cross-section with a U-web (22) located below the height position of
the
constriction (14), an inner leg wall (23) of the lid recess (V) being part of
a dome wall
of a dome (2) including a dome top surface (5) located above the height
position of the
constriction (14) and the clamping groove (1), characterised in that the lid
recess (V) is
formed with such a depth to extend downwards beyond the height position of the
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constriction (14), and with an outer diameter (D1) at the outer surface (6)
and at the
height position of the constriction (14) such that the lid recess (V) defines
a centering
and guide projection (K) for an easy clip-on operation of the lid (D) onto the
bead (10)
of the receptacle (C), and in that the lid recess (V) is formed with such a
depth to
extend downwards beyond the height position of the constriction (14), and also
downwardly beyond a corresponding skirt (18).
Preferably, there is also provided a lid (D) of plastic material for a
receptacle (C)
having an exterior bead (10) in an opening area (9), the lid (D) being
provided with a
peripheral clamping groove (1), which is open on the lower surface of the lid
to receive
therein the bead (10), the clamping groove (1) being continued at an outer
lower end
thereof by an elastically expandable constriction (14) and at an inner lower
end
thereof by a cylindrical or conical outer surface (6) of an outer leg wall (4)
of a
circumferentially extending lid recess (V) of substantially U-shaped cross-
section with
a lid recess U-web (22) located below the height position of the constriction
(14), an
inner leg wall (23) of the lid recess (V) being part of a dome wall of a dome
(2)
including a dome top wall (5) markedly above the height positions of the
constriction
(14) and a clamping groove (1) characterised in that a penetration region (25)
of
predetermined size is formed in the dome top wall (5), a penetration region
(25)
thinner wall thickness (xl) than at least the dome top wall thickness (x), and
that the
penetration region (25) is formed with crossing score lines (26) for
introducing a straw.
According to the present invention, there is also provided a lid (D) of
plastic material
for a receptacle (CD) having an exterior bead (10) at a conical and stepped
opening
area (9a), the lid (D) being provided with a peripheral clamping groove (1)
which is
open on a lower surface of the lid for receiving therein the bead (10), the
clamping
groove (1) being continued at an outer lower end thereof by an elastically
expandable
constriction (14) and at an inner lower end thereof by a cylindrical or
conical outer
surface (6) of an outer leg wall (4) of a circumferentially extending lid
recess (V) of
substantially U-shaped cross-section with a U-web (22) located below the
height
position of the constriction (14), an inner leg wall (23) of the lid recess
(V) being part of
a dome wall of a dome (2) including a dome top wall (5) located above the
height
positions of the constriction (14) and the clamping groove (1), characterised
in that the
lid recess (V) is formed with such a depth to extend downwards beyond the
height
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position of the constriction (14), and with an outer diameter (D1) at the
outer surface
(6) at substantially the height position of the constriction (14) such that
the lid recess
(V) defines a centering and guide projection (K) for co-action with the
conical and
stepped opening area (9a) of a double wall receptacle (CD) allowing an easy
clip-on
operation of the lid (D) on to the bead (10), and in that the lid recess (V)
is formed with
such a depth to extend downwards beyond the height position of the
constriction (14),
and also downwardly beyond a corresponding skirt (18).
Preferably, there is also provided a cup-shaped receptacle (C, CD) provided
with a
plastic material clip-on lid (D), an opening area (9) of the receptacle (C)
being
delimited by an upwardly and outwardly tapering conical receptacle wall (7)
and an
outwardly projecting bead (10), the lid (D) being formed with a peripheral
clamping
groove (1) which is open on a lower surface of the lid for receiving therein
the bead
(10), the clamping groove (1) having at an outer lower end region an
elastically
expandable constriction (14) and at an inner side a cylindrical or conical
outer surface
(6) of an outer leg wall (4) of a circumferentially extending lid recess (V)
of U-shaped
cross-section, a U-web (22) of the lid recess (V) being located below the
height
position of the constriction (14), the inner leg wall (23) of the lid recess
(V) being part
of a dome wall of a dome (2) having a dome top wall (5) located above the
constriction
and the clamping groove, respectively, characterised in that the lid recess
(V) is
formed with such a depth to extend downwards beyond the height position of the
constriction (14) and has an outer diameter (D1) at the outer surface (6) at
the
elevation of the constriction (14) adapted to the inner diameter (D7) of the
receptacle
wall (7) at the bead (10) such, that during an easy clip-on operation of the
lid (D) the
lid recess (V) outer surface (6) functions as a lid centering and guide
projection (K) co-
operating by sliding contact with the receptacle wall (7) at least while the
bead (10)
moves past the constriction (14) into the clamping groove (1), when downwardly
directed clip-on pressure (R) mainly is applied to the dome (2); and that the
lid
centring and guide projection (K) and the clipped-on clamping groove (1)
commonly
define an annular receptacle opening area stiffening structure for preventing
radial
receptacle opening area deformations.
Preferably, since, according to the invention, the outer leg wall has a
relatively long
downward extension, the U-web of the lid recess, and the inner leg wall
commonly
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4a
constitute a rigid centering and guide projection which slidingly contacts the
receptacle
wall at least already while the bead moves past the constriction. The clamping
groove automatically is precisely centred on the bead, and the bead is clipped-
on
CA 02426713 2006-01-10
virtually at one go and along its whole circumferential length, past the
constriction into
the clamping groove by applying pressure essentially only on the dome top
wall. The
sliding contact between the outer surface and the receptacle wall guides the
constriction uniformly over the bead, since thanks to guidance and centring,
the bead
generates uniform resistance against the lid downward movement everywhere. The
guiding projection converts the pressure applied to the dome into a downwardly
oriented pulling force uniformly distributed along the constriction to pull
the constriction
uniformly past the bead, until the bead is correctly positioned in the
clamping groove.
This advantageous effect of the centering and guide projection, which actually
is a
cone or a cylinder, and the uniform force transmission, in co-action allow to
provide a
strong force fit between the bead and the clamping groove, said force fit
resulting from
a relatively narrow dimensioning between the bead and the clamping groove and
the
given elasticity. This assures that the clipped on lid prevents leakage, and
that the
bead does not even locally leave the clamping groove if the full cup falls
over. The
shape of the dome and of the lid recess result in a rigid structure integrated
into the
lid, by which structure the applied clip-on force effectively clips on the lid
without
significant buckling of the lid. The clipped on lid markedly stiffens the
opening area of
the receptacle resulting in excellent spill-proofness and good leakage-
proofness as
well.
Preferably, an aspect of the invention is a circumferentially continuously
operating
hinge mechanism integrated into the lid. This allows to easily ciip-on the
lid, in
practice by a quick grasp of the hand. As soon as pressure is applied at least
on the
dome top wall, the dome is lowered, the dislocated inner leg wall tilts the U-
web
downwardly about the hinge formed at the transition between the U-web and the
outer leg wall as soon as the resistance to movement of the constriction over
the bead
starts to increase. The tilting movement of the U-web temporarily tends to
pull the
outer leg wall away from the inner wall of the receptacle. The contact between
the
bead and the constriction tilts the constriction outwards and the clamping
groove
diverges somewhat. Due to the clip-on pressure or, if necessary, by
automatically
also or alternatively pressing on the outer lid periphery when the dome is
pushed
downwardly, the bead passes the constriction easily and in one go. When the
pressure ceases, the hinge mechanism re-establishes the fit of the lid, i.e.,
the U-web
returns into a position essentially perpendicular to the axis of the lid and
firmly holds
CA 02426713 2006-01-10
6
the outer leg wall against the inner wall of the receptacle. The constriction
is returned
behind the bead until the bead is in a tight and hermetically sealed force fit
in the
clamping groove. The upwardly protruding dome allows to actuate the joint
mechanisms by first lowering the dome relative to the clamping groove and to
open
the clamping groove before the bead slips through. Then the dome returns into
its
initial elevated position. During clip-on the dome top wall may be lowered by
the
applied pressure until the palm of the hand assists at the lid periphery to
easily
complete the clip-on action.
The bead of the receptacle can be formed as a curled bead or a full rolled
rim, or a
partially curled bead or half rolled rim, or instead as an outwardly bent edge
flange.
An easy and comfortable clip-on action of the lid is achieved in any case,
resulting in
the final leakage-proofness and the stable lid holding effect. One lid design
fits many
bead designs.
Preferably, the lid is designed in view to an optimised and easy clip-on
action, despite
a powerful force fit in the clipped on condition. Thanks to its shape the lid
is relatively
stiff in its central region such that the bead easily and completely can be
clipped-in the
clamping groove into a tight form fit and force fit just by pressing in clip-
on direction,
assisted by the guidance of the guide projection, and by temporarily opening
the
clamping groove by a movement of the dome relative to the constriction.
For this function it may be important that the U-web extends substantially
planar and
substantially perpendicularly to the lid axis, and that the inner leg wall is
substantially
parallel to the lid axis. Due to those structural features the integral hinge
mechanism
is acting well when downward pressure is applied on the lid, mainly:since for
mechanical reasons the inner leg wall behaves more rigid than the outer leg
wall when
the U-web is tilted such that consequently the outer leg wall has to yield
inwards and
then temporarily opens the clamping groove from the inner side.
It may be expedient when the outer surface slidingly co-operates with the
receptacle
wall already before the bead starts to deform the constriction elastically.
This has the
effect that the clamping groove and the constriction, respectively, are put
over the
bead at a neatly centred position so that the bead will have to overcome
essentially
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7
the same resistance to passage over its whole circumferential length and
therefore
easily and uniformly is clipped into the clamping groove.
When the cone angles of the outer surface and of the receptacle wall are
approximately identical, the outer diameter of the outer surface should
correspond, at
the height position of the constriction, at least approximately to the inner
diameter of
the receptacle wall in the opening area so that the centering and guide effect
already
starts before the bead reaches the constriction. When the bead snaps into the
clamping groove, especially the softer material of the receptacle will yield
in the bead
and in the receptacle wall so that a strong positive engagement will be
established,
when the lid is clipped-on. Additively or alternatively, also the outer leg
wall of the lid
recess may slightly yield inwards, as a consequence of the contact pressure
between
the outer surface and the receptacle wall.
The outer diameter of the outer surface in the clamping groove even may be
markedly
larger than the inner diameter of the receptacle wall in the opening area,
i.e. where the
inner wall curves outwardly into the bead. This measure guarantees that during
the
whole movement of the bead past the constriction into the clamping groove a
significant guidance and centring will take place. A diameter oversize of
approx. 3.5%,
i.e. in a range between approx. 1.5% and 5%, depending on the size of the
receptacle, may be expedient.
Preferably, a markedly downward extension of the outer surface beyond the
height
position of the constriction is for the intended centring and guiding effect.
The lid may
be clipped-on by mere application of pressure substantially only on the dome.
The
outer surface may have at least 2.5 times the height of the clamping groove.
Providing
3 times the height, or even 4 times the height of the clamping groove may be
still
better. It is to be noted that, due to the pressure between the outer surface
and the
receptacle wall and by a large contact area an extremely effective sealing
effect will
result complementary to the sealing effect of the bead in the clamping groove.
A cone angle between approx. 6 and 12 , i.e. an overall cone angle between
approx.
12 and 24 , may be expedient. A preferred angle range amounts to between
approx. 8 and 10 , i.e. between approx. 16 and 20 in total.
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7a
Preferably, depressions formed where the top of the dome top wall merges with
the
outer dome wall facilitate the easy clip-on action of the lid and increase the
rigidity of
the dome. Furthermore, the depressions provide visual clues where to apply the
fingers and define gripping spots for comfortably removing the lid from a lid-
stack.
Undercut depressions do not only provide a hand grip, but even may define lid
stacking shoulders. Each lid may only rest with the shoulders of the
depressions on
the dome top wall of the next lid such that the lids in the stack can not get
jammed.
Preferably, in order to achieve the strong force fit between the bead and the
clamping
groove, which is important for the sealing effect, the radial thickness of the
bead
should be larger than the radial interior width of the clamping groove. The
soft paper
or paperboard material of the receptacle and the material of the bead,
respectively,
yield on the inner side and on the outer side as soon as the bead is seated in
the
clamping groove. Squashed zones with planar contact areas, i.e. not only line
contacts, result in an improved sealing effect.
Preferably, the radial thickness of the bead should be between 10% and 20%,
preferably approx. 15%, larger than the average radial interior width of the
clamping
groove. This dimensioning results in a good sealing effect and,
simultaneously, only
moderate forces will be necessary for clipping the lid onto the receptacle.
In order to enhance the holding effect of the lid on the bead and to gradually
squash
the material, the radial interior width of the clamping groove may decrease in
a
direction opposite to the clip-on direction; expediently with the cone angle
of the
receptacle wall. The clamping groove will, in this way, produce a wedge effect
until the
bead finally settles in position.
Preferably, in order to improve the holding effect for the clip-on lid at
least one belt-like
zone with an increased coefficient of friction ought to be provided at the
outer surface
of the outer leg wall and/or at the inner wall of the receptacle. This might
result in an
increased friction engagement between the lid and the receptacle and a stiff
cup
opening region.
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7b
Preferably, a further aspect of the invention is that the constriction may
consist of
successive deeper and shallower depressions formed from the exterior.
Preferably,
the deeper depressions are longer in circumferential direction than the
shallower
depressions. This facilitates the clip-on action but results in a stable and
durable
holding effect, and stiffens the lid periphery.
A plurality of upwardly protruding beverage distinguishing protrusions in the
dome top
wall may be provided to allow identification of the type of liquid from
outside, e.g.
coke, diet coke, orange juice, etc. The protrusions may be push-in buttons.
Preferably, a further aspect is a penetration region formed in the dome top
wall. This
region may have a thinner wall thickness than at least the dome top wall, and
has
intersecting score lines through which a straw comfortably may be introduced
by
breaking the score lines. The reduced wall thickness allows to insert the
straw more
easily. The reduced wall thickness may be produced by locally compressing the
material of the lid. The region with reduced wall thickness is particularly
useful for a
relatively stiff lid having a somewhat thicker wall than such conventional
lids.
Providing the thinner region, however, is of general advantage for all such
lids,
because this measure generally facilitates the introduction of a straw.
Preferably, the penetration region for introducing a straw expediently is
provided at the
bottom of a recess e.g. located in the centre of the dome top wall. The
reduced
bottom wall thickness increases the rigidity of the dome in view to the easy
clip-on
action.
The penetration region may be curved inwardly to facilitate the introduction
of a straw
and to increase the resistance against buckling outwards by liquid pressure.
The
curvature also leads to an automatic closing effect of the broken score lines
after the
straw is withdrawn and when liquid pressure acts from inside on the flaps
defined by
the broken score lines. A contour of the recess corresponding to two ellipses
the
main axes of which are offset to each other by 90 increases the rigidity of
the dome
and offers an attractive appearance of the dome design. The score lines
expediently
are formed along the main axes of both ellipses. It might suffice to have only
a thin
walled core portion of the bottom instead to facilitate the introduction of a
straw.
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7c
Preferably, a further aspect of the invention is directed to an easy clip-on
lid for a
conical double wall paper or cardboard receptacle. Double wall paper or
cardboard
receptacles, conventionally, have an opening area where the inner receptacle
wall is
deformed outwardly at a step and is connected with the outer receptacle wall.
The
bead is formed on the upper end of the inner receptacle wall. The cone angle
of the
conical inner wall of the double wall receptacle is bigger below the widened
upper
opening area which forms a continuation of the lower receptacle wall by a
circumferential shoulder and has a smaller or even zero cone angle than the
lower
receptacle wall. The lid placed on the bead already contacts the widened
opening
area inner wall by the centring and guide cone when the bead reaches contact
with
the constriction. During the clip-on action the lid is centred and guided over
the bead.
The centring and guide projection is pulled inwardly due to the deformation
taking
place between the pressed down dome and the clamping groove such that the bead
more easily passes the constriction. The lid, when clipped-on, provides high
leakageproofness and stiffness in the receptacle opening region.
Preferably, the cone angle of the outer surface or the centring and guide
projection
either may be zero or has a value which is smaller than the angle value of the
cone
angle of the receptacle inner wall. The rigid centering and guide projection
forces the
bead into a leakageproof seated condition in the clamping groove and even may
cause a deformation of the opening area of the double wall receptacle for
intensified
receptacle rim portion stiffening and sealing purposes.
Preferably, the centering and guide projection, in this case, ought to be
continued
downwardly by an inward stepped portion of the outer leg wall dimensioned for
a
press-fit co-action with the receptacle wall. The inwardly stepped portion
should have
a cone angle essentially equal to the cone angle of the inner receptacle wall
below the
upper stepped opening area. The co-action between the stepped portion and the
receptacle inner wall provides an intensified sealing effect even deep inside
the
receptacle.
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8
Embodiments of the invention are explained making reference to the drawings,
in
which:
Fig. 1 is a side view of a lid,
Fig. 2 is a section along the axis of the lid of Fig. 1,
Fig. 3 is a section along the axis of a receptacle for which the lid of Fig. 1
and
Fig. 2 is intended to be used,
Fig. 4 shows an enlarged sectional view of a phase during the clip-on
operation of the lid onto the receptacle,
Fig. 5 shows a sectional view of a phase in which the lid has fully been
clipped
onto
the receptacle,
Fig. 6 is an axial sectional view of a further embodiment of a lid,
Fig. 7 is a side view of a part of the lid of Fig. 6,
Fig. 8 is a part of a portion of the lid of Fig. 6, in a phase of the clip-on
action of
the lid in which the bead of the receptacle just has reached the
constriction,
Fig. 9 is a view corresponding to Fig. 8, in a phase of the clip-on action, in
which the clamping groove temporarily is opened somewhat during
clipping-on of the lid,
Fig. 10 is a view corresponding to Fig. 8, in a phase in which the lid is
clipped-
on properly,
Fig. 11 is a plan view of the dome of the lid of Fig. 6,
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9
Fig. 12 is an axial section in the centre of the dome of Fig. 11 in the
section
plane
XII -XII,
Fig. 13 is an axial sectional view of a further embodiment of a lid,
Fig. 14 is a view of the lid of Fig. 13 from above,
Fig. 15 is a lid stack consisting of several lids of Figs 13 and 14,
Fig. 16 is an axial sectional view of a lid and a double wall receptacle in a
preparatory phase of a clip-on action of the lid,
Fig. 17 is a sectional view similar to Fig. 16 with the lid fully clipped-on
the
double wall receptacle, and
Fig. 18 is a sectional view similar to Fig. 5, of another embodiment.
A lid D, which is intended to be used for a cup-shaped receptacle C consisting
of
paper or paperboard or plastic material is e.g. drawn from elastic plastic
foil material
and has a wall thickness of e.g. 0.3 to 0.5 mm (Fig. 1). The lid is adapted to
be
clipped on an opening area 9 of the receptacle C such that said receptacle C
is closed
in a leakage-free manner and such that the lid D will not come off, not even
if the full
receptacle C falls over. The lid D (Fig. 1) is provided with a peripheral,
circumferentially continuous clamping groove 1, above the plane of which a
dome 2
vaults on the inner side of the clamping groove 1. The dome 2 is separated
from the
clamping groove 1 by a circumferential substantially uniform lid recess V and
is
provided with an essentially planar dome top wall 5 and several
circumferentially
distributed depressions 3. Relative to the clamping groove 1, an outer leg
wall 4 of a
lid recess V (Fig. 2) extends markedly downwards beyond the plane of the
clamping
groove 1.
.~__._~. .._.__._.._... __.._.__.._
-._....._....._~._..___... _._ _ _
CA 02426713 2003-04-28
The lid D (Fig. 2) is clipped onto the opening area 9 of the receptacle C
(Fig. 3) by
applying press ure R e.g. only on the dome top wall 5 in clip-on direction.
The dome
top wall 5 exte nds essentially parallel to the plane of the lid D. The lid
recess V has a
U-shaped cross-section and concentrically surrounds the dome 2. The lid recess
V is
bound by the outer leg wall 4, which in this embodiment tapers conically
downwards, a
lower U-web 22, and an inner leg wall 23 which forms an upwardly extending
outer
dome wall. The outer leg wall 4 has an outer surface 6 which extends into the
clamping groove 1. The outer surface 6 is arranged at a conical angle a/2,
which
may correspond at least essentially to the conical angle a/2 of a receptacle
wall 7 of
10 the receptacle C.
At the lower end of the receptacle wall 7 in Fig. 3, a receptacle bottom 8 is
arranged,
whereas the opening area 9 of the receptacle is delimited by the receptacle
wall 7 and
an outwardly projecting bead 10, preferably a so-called curled rim 11
consisting of the
paperboard or paper material of the receptacle C. In the case of a plastic
receptacle,
the bead 10 may also be produced by injection moulding. The bead instead may
be
only a half curled bead or an outwardly projecting receptacle rim flange.
Fig. 4 shows the lid D on the bead 10, which is formed as a curled rim 11. A
constriction 14 of the lid D rests on the bead 10.
The outer leg wall 4 is continued, at the upper end by a wall 12 which extends
approximately parallel to the plane of the lid and by a circumferential apron
13. The
apron 13 extends approximately parallel to the axis of the lid D down to the
constriction 14. The constriction 14 may be a scorelike depression from the
outside
and forms an interior rounded crest 15. The crest 15 and the constriction 14
can be
continuous in circumferential direction, or alternatively can be formed by
individual
local depressions between which (indicated by broken lines) the outer contour
approximately continues. The constriction 14 is continued downwardly by an
outwardly inclined wall 16 defining a clip-on ramp 17. From wall 16, a further
apron 18
extends downwards, terminating at an exterior flange 19. The height of the
further
apron 18 could be shorter than shown.
CA 02426713 2006-01-10
11
The radial thickness Y of the bead 10, measured at the transition from the
straight
receptacle wall 7 to the curvature of the bead 10, may be larger than the
radial interior
width Y1 of the clamping groove 1. The radial thickness Y may exceed the
interior
width Yl by 10% to 20%, preferably by approx. 15%. In the clamping groove 1
the
radial interior width Y1 gradually decreases, preferably with the cone angle
a/2 from
the constriction 14 towards the wall 12.
The clamping groove 1 defines a length L between the crest 15 and the inner
side of
the wall 12. The outer leg wall 4 extends downwards beyond the height position
of the
constriction 14 by a length L1 which may be equal to at least 2.5 times the
height L,
preferably 3 times, and even more preferably 4 times the height L or more.
The outer diameter Dl of the outer surface 6 of the outer leg wall 4 at the
height
position of the constriction 14 (e.g. the crest 15) at least largely
corresponds to the
interior diameter D7 of the receptacle wall 7 at the bead 10, i.e. at the
transition from
the straight receptacle wall 7 to the outwardly directed curvature of the bead
10. The
outer diameter D2 of the outer surface 6 of the outer leg wall 4 at the
junction with wall
12 is even markedly larger than the interior diameter D7, preferably by
approx. 1.5%
to 5.0%, preferably by approx. 3.5%.
When pressure R is applied on the dome 2 in Fig. 4 the outer surface 6 already
slidingly contacts the receptacle wall 7 before or as soon as the bead 10
reaches the
constriction 14. The lid recess V forms a centering and guide projection K
which
supports and facilitates the easy clip-on operation of the lid D. It will be
expedient
when the sliding contact is established even before the bead 10 reaches the
constriction 14. When the lid D is pressed down still further, the bead 10
will deform
the constriction 14 elastically outwards; in the course of this process, also
the bead 10
is slightly deformed before it moves over the crest 15 and snaps into the
clamping
groove 1(Fig. 5). The criss-cross hatched regions shown in Fig. 5 indicate
squeezed
areas 20, 21 formed in the bead 10 and the receptacle wall 7, to promote the
sealing,
the holding and the stiffening effects. Alternatively or additively, also the
outer leg wall
4 may slightly yield inwards (indicated in broken lines at 21').
CA 02426713 2003-04-28
12
The lid D in Figs 6 to 10 differs from the lid D of Figs 1 to 5 by a modified
design of the
constriction 14 and by a recess 24 in the dome top wall 5. The constriction 14
(Fig. 7)
is formed by alternating successive deeper and shallower depressions 16a, 16b.
The depressions 16a, 16b form a snake line shaped inner crest 15'. The deeper
depressions 16a may be longer in circumferential direction than the shallower
depressions 16b. Furthermore, Fig. 7 shows by dotted line 19' a shortened
apron 18.
In Fig. 6 the recess 24 has a bottom dome region 25 of limited size
substantially
parallel to and situated below the dome top wall 5. The wall thickness x of
the lid D is
substantially constant. Only the region 25 is thinner (thickness x 1), e.g. by
compressing the material. The region 25 is situated in the centre of the dome
top
wall 5. For introducing a straw the region 25 is formed with crossing
breakable score
lines 26. Expediently, the region 25 may be curved towards the inner side of
the
dome 2.
The depressions 3 in the transition from the dome top wall 5 to the inner leg
wall 23
increase the rigidity of the dome 2 and allow to grip the lid D by the finger
tips, e.g. in
order to more easily remove the lid D from a stack of lids, and to put the lid
D on the
receptacle C. The clip-on force R even may be applied via the depressions 3 on
the
dome. However, preferably the easy clip-on action may be carried out by
pressing
the palm of the hand on the even dome top wall 5.
In Fig. 6 the outer leg wall 4 may have at least one beltlike circumferential
zone 30 in
which the coefficient of friction is increased in order to achieve an
intensified holding
effect as soon as the lid D is clipped-on. The zone 30 may be situated higher
than
shown, or may be narrower or wider. A respective zone with an increased
coefficient
of friction also could be provided at the receptacle wall 7, either instead of
zone 30 at
the lid, or in co-action with the zone 30 provided at the lid D.
A circumferentially continuous hinge mechanism M is integrated into the lid D
by the
design and the shape of the dome 2 and the lid recess V. The hinge mechanism
may
assist in clipping-on the lid D, as particularly shown in Figs 6 to 10.
_._......_.....,~_..~._._ ...... .....~...
CA 02426713 2006-01-10
13
The hinge mechanism M of the lid D consists of the dome 2, the inner leg wall
23, the
U-web 22, and the outer leg wall 4. The transitions of the outer leg wall 4
into U-web
22 and of U-web 22 into inner leg wall 23 define hinges 29. The inner leg wall
23
extends essentially parallel to the longitudinal axis of the lid, while the U-
web 22 is
planar and perpendicular to the lid axis. It is to be noted that due to the
rigidity of the
dome 2 and due to the smaller diameter of the inner leg wall 23 in relation to
the
bigger diameter of the outer leg wall 4, the outer leg wall will yield
inwardly easier than
the inner leg wall 23. This effect is used to temporarily open the clamping
groove I
and to achieve an easy lid clip-on action.
In Fig. 8 the lid D is put on the bead 10 of the receptacle C such that the
entire
circumferential extension of the constriction 14 will become is centred on the
bead 10.
The outer leg wall 4 contacts the receptacle wall 7. Now a clip-on force R is
applied
e.g. to the dome top wall 5, e.g. by the flat hand until the dome top wall 5
lowers (Fig.
9).
In Fig. 9 a reaction force R' acts counter to the clip-on force R, since the
constriction
14 seats on the bead 10. The inner leg wall 23 tilts the U-web 22 downwards by
the
inner hinge 29 at the transition from the inner leg wai( 23 into.the U-web 22.
Thanks
to the radial rigidity of the dome 2 the tilting of the U-web 22 results in a
force 28
acting at the outer hinge 29. The force 20 relieves the outer leg wall 4 from
the
receptacle wall 7 such that even the clamping groove 1 may open somewhat at
the
inner side. The apron 18 is displaced outwards in the direction of an arrow 27
by the
reaction force R', such that even the clamping groove I temporarily may open
somewhat at the outer side. Under the clip-on force R, and, because dome top
wall 5
is lowered, by then possibly also pressing on the wall 12, the bead 10 slides
past the
constriction 14 until it finally snugly is clipped into the clamping groove 1.
In Fig. 10 the clip- on force R has ceased. The U-web 22 returned by
elasticity into
the orientation essentially perpendicular to the lid axis and presses the
outer leg wall 4
against the receptacle wall 7. The apron 8 also returned by elasticity. The
clamping
groove 1 firmly holds the bead 10. The centering projection K and the clamping
groove 1 both significantly stiffen the opening portion of the receptacle C.
CA 02426713 2006-01-10
14
In Fig. 11 the recess 24 has a wa!l contour like a quatrefoil, i.e. a contour
which may
be characterised by two equally sized ellipses the main axes of which are
offset by
900. The score lines 26, in the region 25 extend along the main axes of both
ellipses.
Fig. 12 shows the difference between the wall thickness x and the wall
thickness Xl in
region 25 in exaggerated scale. The region 25 may be curved inwardly, as
shown, or
may be parallel to the dome top wall 5. The reduced wall thickness xl is not
needed
for the entire region 25. It could suffice to provide only a thin walled
central portion of
the region 25, e.g. by compressing the material when producing the lid D.
The radial width of the annular U-web 22 in Figs 6 to 10 may amount to about
10% of
the outer diameter of the lid D, while the diameter of the dome top wall 5 may
amount
to about 60% of the outer diameter of the lid D.
The embodiment of the lid D of Figs 13 and 14 is similar to the embodiment of
Figs 6
to 12 but additionally is provided with regularly distributed beverage
distinguishing
protrusions 5a in the dome top wall 5. There are, e.g., four oval beverage
distinguishing protrusions 5a, each having a marking and/or a pushable button
in its
top. This is standard equipment of many lids on the market. The protrusions 5a
are
located with a small radial distance from the outer edge of the dome top wall
5 and
also with a small radial distance from the central recess 24. Furthermore, the
depressions 3 are made undercut such that they may be gripped more easily by
the
finger tips when the lid D has to be removed from a stack of several lids (as
shown in
Fig. 15). Each depression 3 may define a lateral shoulder 3a which may serve
as a
stacking stop as shown in Fig. 15 such that shoulder 3a rests on the dome top
wall 5
of the next lid D of the stack. The shoulder 3a expediently prevents that the
stacked
lids get jammed within each other, because the stacked lids contact each other
mainly
where the shoulders 3a rest on the dome top wall 5 and where the outer leg
walls
contact each other. This feature results in an orderly and dense stack from
which
each lid D can be removed comfortably. In the embodiment shown, eight
depressions 3 are provided.
The lid D of Figs 13 to 15 also has the centering and guide projection K (a
guide cone)
and the hinge mechanism M for facilitating the clip-on action.
CA 02426713 2006-01-10
Figs 16 and 17 show an easy clip-on lid D for a double wall receptacle CD. The
double wall receptacle CD has an inner wall 7 and an outer wall 7c with an air
gap in-
between to provide a thermal insulating effect. The bead 10 is formed at the
upper
end of the inner wall 7. The double wall receptacle CD first is formed with a
cone
angle a/2 which continues to the bead 10. During the forming process the upper
part
of the inner wall 7 is widened outwards such that the opening area 9a results
where
the cone angle a'/2 is smaller than the cone angle a/2, or even almost zero,
and such
that a shoulder 7b is formed. The lid D for the double wall receptacle CD has
the
already described centering and guide projection K. In this case the
projection K is
10 formed such that the outer surface 6 either is cylindrical (as shown) or
has a small
cone angle R/2 between 00 (cylindrical) or a value similar but smaller than
the cone
angle 02. The outer surface 6 or the outer leg wall 4 is continued by an
inwardly
stepped wall portion 4b such that a shoulder 4a is formed. The outer surface
portion
6a of wall portion 4b is inclined with cone angle a/2. The bottom of the
centering and
guide projection K is formed by the U-web 22 which extends substantially
perpendicular to the central lid axis. The diameter Dl of the outer surface 6
corresponds essentially to the diameter D7 of the opening area 9a in the
region of the
bead 10. In the opening area 9a inner parts of the inner receptacle wall 7a
and outer
parts of the outer leg wall 4 and the wall portion 4b are indicated to be
deformed or to
get into intimate pressure contact when the lid D is fully clipped-on the
double wall
receptacle CD.
In Fig. 16 the lid D is centred on the double wall receptacle CD such that the
bead 10
has approached the constriction 14 from below. Then the outer surface 6
already
contacts the inner receptacle wall 7a in the opening area 9a to properly
centre and
guide the lid D when the clip-on pressure R is applied e.g.: on the dome top
wall 5 (not
shown in Fig. 16).
While the clip-on pressure forces the constriction 14 over the bead 10, the
outer
surface 6 is guiding the lid D. When the U-web 22 is tilted downwardly, as
already
explained above, the outer leg wall 4 is somewhat dislocated inwardly, while
the
constriction 14 yields outwardly. This facilitates that the constriction 14
easily slips
over the bead 10 until the position of Fig. 17 is reached. The bead 10 then is
gripped
from the outer side and the inner side. The contacting wall parts (20 and 20')
may
CA 02426713 2003-04-28
16
become squeezed. The shoulder 4a either is seated on the shoulder 7b or at
least is
close to shoulder 7b. A particular contact pressure is achieved in the region
20'
resulting in an additional sealing effect in addition to the sealing effect
achieved by the
co-action between the clamping groove 1 and the bead 10 and between the outer
leg
wall 4 and the inner receptacle wall portion 7a. In Fig. 17, the rigid dome
structure of
the lid D even rnay force the inner receptacle wall portion 7a into a parallel
relationship
to the outer leg wall 4 resulting in a high holding force and an excellent
effect and a
markedly stiffened opening portion of the closed receptacle CD.
Additionally, the co-action between the shoulders 4a, 7b may result in a clip-
on limiting
stop preventing that the bead will be deformed too much. The abutting
shoulders 4a,
7b even may maintain the bead 10 and the clamping groove 1 in a preloaded
closing
condition characterised by high Ieakage-proofness and high holding force for
the lid D.
Fig. 18 is a sectional view of clipped-on lid D on one-wall receptacle C,
similar to Fig.
5. Bead 10 is fully curled inwards. Clamping groove 1 of the lid D is of round
cross-
section. The criss-cross hatched areas represent zones of strong contact, e.g.
of
even slightly squeezed surface portions. There is tight contact between the
clamping
groove I and the bead 10 over more than 1800 of the circumference of the bead
10.
The outer leg wall 4 significantly stiffens the upper opening region against
radial
deformation.
_._..___....____.. .~,.._....._.._____._
