[0001] The closures for jars and bottles used nowadays provide a clamp force by twisting
the closure on the jar or bottle. The screw thread or the lugs of the closure hook
behind the screw thread of the jar or bottle. This causes that the top side of the
closure is pulled on the upper rim of jar or bottle. The gasket material that is on
the inside of the closure will be deformed and provides the sealing of the packaging.
In many packaging with closures a vacuum is present, because of cooling of the contents
after filling or because one or more gasses in the space above the product chemically
react with the product or because steam is injected inside the packaging before closing
or because of another reason. This vacuum inside the packaging causes a normal force
that can be added at the earlier mentioned clamp force. Clamp force and normal force
determine the friction force between closure and jar or bottle that has to be overcome
to be able to open the packaging. The friction force is expressed in a torque with
which the packaging can be opened.
[0002] Closures made out of one part, are hard to open because the clamp force and the force
caused by the vacuum inside the packaging together determine the torque needed for
opening. The sum of these two forces is in practice this high that a share of the
users of these packaging is not able to open the packaging in the way it is meant,
by taking the cap in the hand and twisting it. These users are thrown on the resources
of the use of tools, the application of certain actions or on the help of third parties.
Many solutions have been developed to solve this problem. Till now this has not lead
to an acceptable solution. There are solutions in which the closure is built up out
of several parts that are not easy to process, for which extra productions steps are
needed and/or that are hard to replace after opening to reseal the packaging that
is not empty yet.
Other solutions provide ways to get rid of the vacuum inside the packaging for example
to make a hole in the cap. A great disadvantage of these solutions is that it is hard
to reseal the packaging because the closure is mostly being damaged and air tight
closing is not possible anymore. There are also solutions in which a plug of a soft
material is adjusted on the top part of the closure which can be taken or pushed away
to open the closure and to get rid of the lower air pressure inside the packaging.
These plugs cannot withstand the internal pressure which can occur during certain
processes like sterilizing because of stability and shelf life of the product in all
occasions or are not able to stay close because of loads occurring during transport.
[0003] In general composite closures are easier to open. An example of a closure built up
out of more parts is given in US patent 1920286. The objective of this patent was
material savings and easy opening is not mentioned in this patent.
The closure in US patent 1920286 consists out of a disc shaped inner cap that is clenched
to the rim of the packaging by a screw ring with an inturned flange. By splitting
up a closure in two parts it is possible to vary the thickness of the parts and adjust
it to the function the parts have to fulfil as has been done in US patent 1920286.
Material savings are possible in this way. If the screw ring with inturned flange
has been taken off the jar or bottle, the disc shaped inner cap has to be taken off
separately. The disc shaped inner cap in US patent 1920286 may not have a larger diameter
than the outer diameter of the opening of the jar or bottle.
Detailed description of the invention
[0004] The invention, a closure for jars and bottles, consist at least out of two parts.
A ring shaped part with screw thread or lugs with an inturned flange (1) and a disc
shaped inner cap (2). The ring shaped part with inturned flange with screw thread
or lugs (1) clenches a disc shaped inner cap (2) on the rim of the packaging.
On the disc shaped inner cap (2) a gasket (deformable plastic) material (4) has been
applied. The clench force to seal the packaging is provided by the ring shaped part
with screw thread or lugs with inturned flange (1) together with the screw thread
of the jar or bottle.
[0005] The friction force between closure and jar or bottle with the current closures is
determined by the clench force of the closure and the normal force because of a vacuum
in the package. The invention of this closure is based on the principle that clench
force and normal force will be eliminated at different moments in time. At opening
the packaging by twisting the cap firstly the clench force will be eliminated and
next the normal force will be overcome. Because of this disconnection of the forces
the torque of opening is reduced considerably compared with common used closures and
the way of opening stays the same.
[0006] The invention is an extension of patent US 1920286 in which a description of a closure
made out of two parts is given. New is that the disc shaped inner cap is raised automatically
during twisting by a radial inwardly directed feature (3) which has been fit to the
ring shaped part with screw thread or lugs with inturned flange (1). The disc shaped
inner cap (2) must have a larger diameter than the outer diameter of the rim of the
jar or bottle so the inwardly directed feature (3) can apply to edge of the disc shaped
inner cap (2).
[0007] The mentioned feature (3) can be formed in different ways. The feature can be circumferentially
or screw threaded (3) applied completely of partly across the outline, but can also
be a single feature in the form of a stud (3) of certain dimensions or more studs
(3) of certain dimensions. The advantage of applying one feature (3) across the circumference
or applying more stud shaped features (3) is that the disc shaped inner cap (2) can
move in the ring shaped part with screw thread or lugs (1) but cannot fall out.
[0008] When applying more than one inwardly directed studs (3) it is possible to position
one of the studs (3.1) higher in the ring shaped part with screw thread or lugs (1)
with the advantage that the disc shaped inner cap (2) is pushed up firstly by the
higher placed stud on one spot, like a pealing movement by which the needed force
to overcome the normal force which is on the disc shaped inner cap (2) is smaller
than would be the case if the disc shaped inner cap (2) has to be lifted uniformly
across the circumference.
[0009] Applying the mentioned feature (3) at the composite closure means that the closure
can be opened much easier than the common used composite closures or the closure made
out of one part. The packaging can be resealed after opening and can fulfil the function
in the same way as before opening.
Figure 1 and 2 shows a jar (it can also be a bottle) with the described closure applied
to it.
Figure 3 shows the closure with the ring shaped part with inturned flange (1) and
the disc shaped inner cap (2). The figure also shows the feature (3), in the form
of an inwardly directed stud that lifts the disc shaped inner cap (2) when twisting
the cap.
Figure 4 shows also the gasket material (4) that is applied to the disc shaped inner
cap (2) and the lugs (5) that hook behind the screw thread of the jar or bottle.
Figure 5 shows a cross section of, in this case, a jar with a closure with the ring
shaped part with inturned flange (1) and the disc shaped inner cap (2). Also the feature
(3) can be seen, in this case in the form of an inwardly directed stud that lifts
the disc shaped inner cap (2) when twisting the closure.
Figure 6 shows the cross section in detail and it is possible to perceive that the
inwardly directed feature (3) will hook under the disc shaped inner cap (2). It can
be perceived that the diameter of the disc shaped inner cap (2) is larger that the
upper rim of the jar. Also the gasket material (4) can be seen.
Figure 7 shows two features (3), in this case in the form of inwardly directed studs
(3.1) and (3.2) that are applied in the ring shaped part with inturned flange (1)
at different heights. The higher applied stud (3.1) will lift the disc shaped inner
cap (2) firstly when twisting the ring shaped part with inturned flange (1) and will
release the vacuum in the jar of bottle.
Applications, characteristics and remarks
[0010]
- The closure can be used on glass jars and bottles in which products are being packed
for which a certain shelf life has to be guaranteed. Examples are foods like vegetables,
fruits, juices, bouillon, soups, meat products, sauces and the like.
- In principle the closure can be applied with the same equipment as existing closures
that are made out of one part.
- The closure can be applied with the same tamper evident function as existing closures
that are made out of one part, like the closures that snaps down because of vacuum
inside the packaging, the so called button function, or like the application of a
tamper evident seal.
- The closure can be applied by hand or by equipment.
- The closure can also be provided with a bayonet catch.
- The gasket layer can also be applied as a loose ring which means that the closure
consists at least out of three parts.
- The thicknesses of the disc shaped inner cap (2) and the ring shaped part with screw
thread and inturned flange (1) can be adjusted to their functions separately so material
savings can be reached comparing with the closure made out of one part.
- The feature (3), in what ever shape, can be applied by forming the ring shaped part
with screw thread with inturned flange (1).
- The feature (3) can also be applied by one or more separate parts that are put in
the inside of the ring shaped part with screw thread (1) and that are locked in the
ring shaped part with screw thread (1) or that are connected to the ring shaped part
with screw thread (1) with or without making holes in the rings shaped part (1).
- The feature (3) can be applied to the ring shaped part with screw thread (3) at a
certain moment during the production of the closure or during the packaging process.
- The closure can be resealed after opening the jar or bottle.
- The invention as described for jars or bottles can also be applied for easier opening
of tanks or vessels in which a vacuum has come into existence by cooling or on another
way. For example tanks and vessels in the process industry, petrol tanks or vessels
or kegs that are being used for transport of matter.
1. A closure especially meant for jars and bottles in which a vacuum is present, that
can be applied in the same way as current closures with screw thread or bayonet catch.
A tamper evident function can be applied in the same way as with current closures
made out of one part like a button function in the disc shaped inner cap (2) or a
tamper evident seal. The closure is made up out of two parts, a ring shaped part with
screw thread or lugs with inturned flange (1) and a disc shaped inner cap (2) on which
a gasket material, tightened or not, has been applied. The closure is easier to open
than the common closures made out of one or more parts.
2. A closure according to conclusion 1 for which the torque needed for opening has been
reduced substantially by the functioning of the invention because the clench force
caused by the closing of the jar or bottle and the normal force caused by the vacuum
inside the jar or bottle, are being released partly or completely at different moments
during opening the closure. During opening at first the clench force will be released
partly or completely and next the disc shaped inner cap (2) will be lifted by an inwardly
directed feature (3) which has been applied in the ring shaped part with screw tread
or lugs with inturned flange (1) by which the vacuum in the packaging will be released.
3. A closure according to conclusion 1 and 2 in which a ring shaped or screw shaped feature
(3) has been applied partly or completely across the circumference of the ring shaped
part with inturned flange (1) and/or one or more studs (3) of certain dimensions are
being used to lift the disc shaped inner cap (2). Applying the feature in the ring
shaped part with inturned flange (1) can be done before, during or after the closing
of the jar or bottle. The inward directed feature(s) make it possible that (3) the
disc shaped inner cap (2) can move inside the ring shaped part with inturned flange
(1) and when the inwardly directed feature are being applied sufficiently across the
circumference the disc shaped inner cap (2) cannot fall out of the ring shaped part
with inturned flange (1).
4. A closure with feature (3) according to conclusion 1, 2 and 3 in which the feature(s)
(3) are being applied in the ring shaped part with inturned flange at different heights
so during twisting of the closure the disc shaped inner cap (2) is lifted on one spot
by which the torque needed for opening and releasing the vacuum is much lower than
when the closure has to be lifted circumferentially.
5. A closure according to conclusion 1, 2, 3 and 4 in which the inwardly directed feature
(3) is formed in the ring shaped part with inturned flange (1) but also can be applied
as one or more loose parts in the ring shaped part with inturned flange (1), with
or without using connection techniques
6. A closure according to conclusion 1, 2, 3 and 4 in which the screw thread or lugs
are being applied after the application of the closure on the packaging.
7. A closure according to conclusion 1, 2, 3 and 4 that also can be used for pressure
vessels, tanks and the like in which a vacuum can be present.