U.S. patent application number 14/182025 was filed with the patent office on 2014-06-12 for method and device for removing a contact lens from a container.
This patent application is currently assigned to Novartis AG. The applicant listed for this patent is Novartis AG. Invention is credited to Roger Biel, Carolin Hartert.
Application Number | 20140161542 14/182025 |
Document ID | / |
Family ID | 43430850 |
Filed Date | 2014-06-12 |
United States Patent
Application |
20140161542 |
Kind Code |
A1 |
Biel; Roger ; et
al. |
June 12, 2014 |
METHOD AND DEVICE FOR REMOVING A CONTACT LENS FROM A CONTAINER
Abstract
There is described a method for the removal of a contact lens
(30) from a container (10), with a contact lens (30) being immersed
in a liquid (20) which is held in a container (10), and the contact
lens (30) being removed from the container (10) together with at
least a portion of the liquid (20) through a removal tube (3) which
is dipped into the liquid (20) within the container (10). First the
container (10) containing the liquid (20) and the immersed contact
lens (30) is closed pressure-tight with a lid (2), which comprises
the removal tube (3) and a pressure tube (5). Both, the removal
tube (3) and the pressure tube (5), are guided through the lid (2).
After the closing of the container (10) with the lid (2) an
overpressure is applied to the interior of the closed container
(10) through the pressure tube (5). The overpressure is applied
such that the contact lens (30) and the liquid (20) are pressed
into the removal tube (3) and removed together therethrough. There
is also described a device (1) for carrying out the method.
Inventors: |
Biel; Roger; (Aschaffenburg,
DE) ; Hartert; Carolin; (Penig, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Novartis AG |
Basel |
|
CH |
|
|
Assignee: |
Novartis AG
Basel
CH
|
Family ID: |
43430850 |
Appl. No.: |
14/182025 |
Filed: |
February 17, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12904190 |
Oct 14, 2010 |
8651774 |
|
|
14182025 |
|
|
|
|
61252476 |
Oct 16, 2009 |
|
|
|
Current U.S.
Class: |
406/142 |
Current CPC
Class: |
B29D 11/0024 20130101;
B29D 11/0023 20130101 |
Class at
Publication: |
406/142 |
International
Class: |
B29D 11/00 20060101
B29D011/00 |
Claims
1-9. (canceled)
10. A device for the removal of a contact lens from a container
comprising a removal tube adapted for being dipped into a liquid
which is held in a container and in which a contact lens is
immersed, and for receiving the contact lens together with at least
a portion of the liquid, wherein the removal tube is held by and
guided through a lid which is adapted for closing the container
pressure-tight, and further comprising a pressure tube which is
held by and guided through the lid and is adapted for being
connected to a source of overpressure.
11. The device according to claim 10, wherein the removal tube
protrudes from a lower face of the lid a longer distance than the
pressure tube, such that with the lid mounted pressure-tight on the
container a front end of the removal tube is located about 1 mm to
about 5 mm above a bottom of the container.
12. The device according to claim 11, wherein the removal tube at
its front end is provided with a funnel having a diameter of about
4 mm to about 9 mm.
13. The device according to claim 12, wherein the removal tube has
an internal diameter of about 2 mm to about 6 mm.
14. The device according to claim 10, wherein the lid is adapted to
maintain an overpressure within the container which amounts to
about 0.5 bar to about 5 bar above ambient pressure.
15. The device according to claim 10, wherein the pressure tube is
adapted to be connected to a source of pressurized air.
16. Use of the device according to claim 10 for the removal of
contact lenses from cuvettes for optical inspection of the lenses.
Description
[0001] This application claims the benefit under 35 U.S.C.
.sctn.119(e) of United States provisional application Ser. No.
61/252,476, filed on Oct. 16, 2009, incorporated herein by
reference in its entirety.
FIELD
[0002] The invention relates to a method for removing a contact
lens from a container with the contact lens being immersed in a
liquid which is held in the container, the contact lens being
removed from the container together with at least a portion of the
liquid through a removal tube which is dipped into the liquid
within the container. The invention also relates to a device used
for the removing of a contact lens from a container.
BACKGROUND
[0003] It is well established in the art to produce hard and soft
contact lenses in an automated production process with reusable
moulds. In mass production of contact lenses, specifically
so-called disposable lenses, a large number of contact lenses must
be manufactured in a relatively short period of time. In an
advantageous method of mass production, a starting material, e.g.,
a prepolymer solution containing water, is introduced into a female
mould half, the casting mould is closed by the respective male
mould half and then the starting material is polymerized and/or
crosslinked with ultraviolet (UV) light. The mould halves mask the
UV light in the respective areas which are outside of the areas
required for contact lens production. Such cyclic mass production
of contact lenses is described, e.g., in WO 98/42497. Suitable
polymers formed by photochemical polymerization of suitable
prepolymers include polymers based on polyvinyl alcohols (PVA) or
silicone hydrogels (SiHy) as well as based on polyethylene glycols
(PEG).
[0004] Besides casting and polymerization and/or crosslinking of
the contact lenses the production process comprises a treatment of
the contact lenses in a number of further treatment stations, such
as, e.g., a coating station, a cleaning station, or an inspection
station. To ensure the quality of the contact lenses in an
automated production process, the finished contact lenses must be
optically inspected. However, contact lenses, in particular soft
contact lenses, are difficult to handle using mechanical means.
Therefore, in the inspection station, for example, the contact
lenses are individually inserted into water filled cuvettes for the
purpose of optical testing. Such a cuvette for optical testing of
contact lenses is known, e.g., from WO 2007/042280. Removal of a
contact lenses from such a water filled cuvette, hither-to is
accomplished by introducing a suction tube into the cuvette. Due to
an underpressure applied through the suction tube the contact lens
is removed from the cuvette together at least with some of the
water contained therein. The problem with this technology lies in
the fact that it requires a considerable technical effort for the
removal of the contact lens and the water from the vacuum system.
For that purpose special vacuum separators are required which are
complicated, costly and require specific maintenance. The
application of vacuum also is limited to a theoretical maximum
pressure difference of about 1 bar. Practically, the achievable
maximum pressure difference lies in the range of about 0.5 bar
only. This small pressure difference may result in a suction power
which is too little, such that not every contact lens is removed
from its respective cuvette.
[0005] It is therefore an object of the present invention to
provide a method and a device for the removal of contact lenses
from containers, such as, e.g., inspection cuvettes, which
overcomes the above-mentioned drawbacks. A method and a device
shall be provided which ensures the removal of contact lenses from
the containers. Complicated and costly vacuum separators shall be
avoided.
SUMMARY
[0006] These and still further objects are met by a method for
removing contact lenses from containers which comprises the method
steps listed in claim 1. The objects are also met by a respective
device for removing contact lenses from containers which comprises
the features listed in the respective independent device claim.
Further improvements of the invention and preferred embodiments are
subject of the respective dependent claims.
[0007] The invention provides a method for the removal of contact
lenses from containers, with a contact lens being immersed in a
liquid which is held in a container, and the contact lens being
removed from the container together with at least a portion of the
liquid through a removal tube which is dipped into the liquid
within the container. First the container containing the liquid and
the immersed contact lens is closed pressure-tight with a lid,
which comprises the removal tube and a pressure tube. Both, the
removal tube and the pressure tube, are guided through the lid.
After the closing of the container with the lid an overpressure is
applied to the interior of the closed container through the
pressure tube. The overpressure is applied such that the contact
lens and the liquid are pressed into the removal tube and removed
together therethrough. More particularly, the method includes the
steps of providing a contact lens immersed in a liquid in a
container, providing a removal tube and dipping the removal tube
into the liquid in the container, providing a pressure tube closing
the container containing the liquid and the immersed contact lens
pressure-tight with a lid comprising the removal tube and the
pressure tube which both are guided through the lid and applying an
overpressure to the interior of the closed container through the
pressure tube such that the contact lens and the liquid are pressed
into the removal tube and the contact lens is removed from the
container together with at least a portion of the liquid through a
removal tube.
[0008] In accordance with the invention an overpressure is applied
for the removal of a contact lens from the container, instead of
the application of a vacuum. Due to the overpressure the contact
lens together with the liquid contained in the container are
removed through the removal tube. The contact lens may then simply
be separated from the liquid by passing the liquid through a sieve
or the like. Thereafter the contact lens may be removed from the
sieve. The novel method does not require a vacuum for the removal
of the contact lens from the container. Consequently, complicated
and costly vacuum separators are avoided. The application of an
overpressure instead of a vacuum also overcomes the limitation of
the maximum possible pressure difference. Theoretically any
pressure difference to ambient pressure may be adjusted.
Practically the achievable maximum pressure difference is only
limited by the burst strength of the container and the
pressure-tight attachment of the lid thereto. Thus, the
overpressure inside the container may be adjusted to a magnitude
which ascertains that every contact lens is removed from its
respective container.
[0009] The removal tube is dipped into the liquid while the
pressure tube may terminate above the liquid level in the
container. It proves advantageous for the capture of the contact
lens if the removal tube is arranged such that its front end is
located about 1 mm to about 5 mm above the bottom of the
container.
[0010] Depending on the kind of liquid in the container, the sizes
of the contact lenses and the configuration of the removal tube it
is found that an overpressure applied to the interior of the
container through the pressure tube of about 0.5 bar to about 5 bar
above ambient pressure is sufficient for definitely removing the
lenses from their respective containers.
[0011] The gas for establishing the overpressure in the container
may be any kind of non-reactive gas and compatible with the liquid
and the lens in the container. For convenience, relative inertness
and availability reasons usually pressurized air will be
applied.
[0012] By arranging an exit opening of the removal tube at a level
which is lower than that of the bottom of the cuvette comparably
small overpressures in the magnitude of about 1 bar are sufficient
for the removal of the contact lenses from their respective
containers.
[0013] There is no need to maintain the overpressure in the
container for a very long time. In a variant of the invention the
overpressure may be applied impulse-like with a duration of from
about 0.75 seconds to about 2 seconds. In combination with the exit
opening of the removal tube being arranged lower than the bottom of
the container e.g. a pressure pulse of the magnitude of 1 bar
applied over less than 1 seconds proves to be sufficient to remove
a contact lens from its container.
[0014] In order to facilitate the entry of the contact lens into
the removal tube in another variant of the invention removal tube
at its front end is provided with a funnel having a diameter of
about 4 mm to about 9 mm.
[0015] The removal tube itself is selected to have an internal
diameter of about 2 mm to about 6 mm to support the rolling up of
the contact lens to a cigar-like shape and thus to facilitate the
transport of the contact lens together with the liquid through the
tube.
[0016] The invention may be used for the removal of contact lenses
from any kind of container having a closed bottom and capable of
being closed pressure tight. The invention proves particularly
useful for the removal of a contact lens from a cuvette for optical
inspection of contact lenses.
[0017] The invention may also be used for cleaning purposes of a
container. Then, after the pressure tight closing of the container
with the lid first a cleaning liquid, such as, e.g., water, may be
introduced into the container through the pressure tube. The
cleaning liquid may then be removed from the container by applying
an overpressure to the interior of the closed container through the
pressure tube, resulting in an emptying of the container through
the removal tube.
[0018] A device for carrying out the method for the removal of
contact lenses from containers comprises a lid which is adapted for
closing a container pressure-tight. A removal tube which is adapted
for being dipped into a liquid, which is held in the container and
in which a contact lens is immersed, and for receiving the contact
lens together with at least a portion of the liquid, is held by and
guided through the lid. The device further comprises a pressure
tube which is held by and guided through the lid and is adapted for
being connected to a source of overpressure.
[0019] The device according to the invention is simple in
construction and may easily be installed and integrated in existing
automated production lines for the manufacture of contact lenses,
without the requirement of major modifications to the production
line or the containers involved. The device allows the application
of an overpressure for the removal of a contact lens from a
container instead of a vacuum. Thus, complicated and costly vacuum
separators may be avoided. The device is adapted for creating an
overpressure inside the container such, that it is ensured that the
contact lens is removed through the removal tube.
[0020] The removal tube protrudes longer from the inside of the lid
than the pressure tube, such that with the lid mounted
pressure-tight on the container a front end of the removal tube is
located about 1 mm to about 5 mm above the bottom of the container.
This construction facilitates the entry of the contact lens into
the removal tube.
[0021] In an exemplary embodiment of the device the removal tube at
its front end is provided with a funnel having a diameter of about
4 mm to about 9 mm. The funnel and its dimensions further assist
the entry of the contact lens into the removal tube.
[0022] The removal tube is selected to have an internal diameter of
about 2 mm to about 6 mm. These diameters assist the rolling up of
the contact lens in a cigar-like manner, which facilitates the
transport of the contact lens through the removal tube.
[0023] In order to ascertain that a contact lens is removed from
the container, the lid is adapted to maintain an overpressure
within the container which amounts to about 0.5 bar to about 5 bar
above ambient pressure.
[0024] Production sites for contact lenses usually are provided
with a central source for compressed air. Thus, it proves
advantageous if the pressure tube is adapted and provided with the
respective connectors to be connected to that source of pressurized
air.
[0025] The device in accordance with the various embodiments
thereof may be used for the removal of contact lenses from any kind
of container having a closed bottom and capable of having an
overpressure created in its inside. A particular application of the
device according to the invention is the removal of contact lenses
from cuvettes for optical inspection of the lenses.
[0026] These and still further features and advantages of the
invention will become apparent from the following description of an
exemplary embodiment of the device for removing contact lenses from
containers, reference being made to the schematic drawings, which
are not to scale, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is device according to the invention which is to be
attached to a container for [0028] i. removing a contact lens
therefrom; and
[0029] FIGS. 2-5 are sectional side views of the device in
combination with a container, [0030] i. such as, e.g. a cuvette for
contact lens inspection, from which the contact lens [0031] ii. is
to be removed.
DETAILED DESCRIPTION
[0032] The following description of an exemplary embodiment of the
invention is for illustrative purposes only and is not intended for
limitation of the scope of the invention.
[0033] FIG. 1 shows a device used for the removal of a contact lens
from a container, such as, e.g., an inspection cuvette for the
optical inspection of a contact lens during contact lens
manufacture. The device, which is generally designated with
reference numeral 1 comprises a plate-like lid 2, which is adapted
for closing a container, such as, e.g. an inspection cuvette,
pressure-tight. The lid 2 has an upper and a lower face, the lower
face in use being directed towards the interior of the container.
In order to achieve a pressure tight sealing of the lid, its lower
face may be provided along a circumference which corresponds to the
shape of the rim surrounding the opening of the container with a
sealing means. Alternatively, the lower face of the lid 2 may be
entirely covered with a sealing material, such as, e.g., a layer of
rubber or the like. Two tubes 3, 5 are guided through the
plate-like lid 2; the penetration bores in the lid 2 for the two
tubes 3, 5 being sealed pressure tight. One of the tubes 3, i.e.,
the removal tube, extends a longer distance from the lower face of
the lid 2 than does the second tube 5, i.e., the pressure tube. The
length of the tube extending from the lower face of the lid 2 is
selected such, that, with the lid 2 mounted and closing a container
pressure-tight, a front end of the removal tube 3 is located about
1 mm to about 5 mm above the bottom of the container. The longer
tube 3 is a removal tube for removing a contact lens together with
the liquid in which the contact lens is immersed. Its front end may
be provided with a funnel 4 which has a diameter f of about 4 mm to
about 9 mm. The removal tube 3 has an internal diameter d which
amounts to about 2 mm to about 6 mm. The rear end of the removal
tube 3 which extends from the upper face of the lid 2, is adapted
to be connected to a tube system for guiding the contact lens and
the liquid to a receptacle. The second tube 5 is a pressure tube.
Its rear end which extends from the upper face of the lid 2, is
adapted to be connected to a pressure source, such as, e.g., a
source of compressed air.
[0034] In FIGS. 2-5 the device according to FIG. 1 is shown in
combination with a container, in which a contact lens is immersed
in a liquid in order to illustrate the method to remove a contact
lens from that container. The container is e.g. a cuvette for
optical inspection of contact lenses during the manufacture process
and is generally designated with reference numeral 10. It is to be
noted that the container may be any other kind of container in
which a contact lens is temporarily immersed in a liquid from which
it is desired to be removed, for example, for continuation of a
production process.
[0035] FIG. 2 shows the device 1 comprising the lid 2 with the
removal tube 3 and the pressure tube 5 in the process of being
lowered onto the rim 11 surrounding the opening 12 of the cuvette
10. This is indicated in FIG. 2 by the arrow A. The cuvette 10 is
filled with a liquid 20, which for example may be water. A contact
lens 30 is shown immersed in the liquid 20 and lying at the bottom
13 of the cuvette 10.
[0036] FIG. 3 shows the device 1 completely lowered to the rim 11
of the cuvette 10. The rim 11 presses against the sealing means on
the lower face of the lid 2. Thereby the cuvette 10 is closed
pressure-tight. In this stage the front end of the removal tube 3
dips into the liquid 20 and is located about 1 mm to about 5 mm
above a bottom 13 of the cuvette 10. The pressure tube 5 is still
located above the filling level of the liquid 20.
[0037] FIG. 4 indicates the emptying of the cuvette and the removal
of the contact lens 30. For that purpose an overpressure is applied
to the interior of the cuvette 10. This is achieved by introducing
a gas, which is generally inert and compatible with the liquid in
the cuvette, with pressure through the pressure tube 5 into the
closed cuvette 10. The flow of gas, usually compressed air, is
indicated by the arrow G in the pressure tube 5. The overpressure
inside the closed cuvette 10 is selected to amount to about 0.5 bar
to about 5 bar above ambient pressure. Due to the overpressure the
liquid 20 is pressed out of the cuvette 10 through the removal tube
3 which is indicated in FIG. 4 by the arrow L and by the lowering
liquid level inside the cuvette 10. Eventually the contact lens 30
will enter into the removal tube 3 and will be transported out of
the cuvette 10 together with the liquid 20.
[0038] In an embodiment of the invention the exit opening of a tube
system (not shown) which is attached to the removal tube 3 is
arranged lower than the bottom 13 of the cuvette 10. By arranging
the exit opening of the removal tube system at a lower level than
that of the bottom 13 of the cuvette 10 comparably small
overpressures in the magnitude of about 1 bar are sufficient for
the removal of the contact lens 30 from the cuvette 10. There is no
need to maintain the overpressure in the cuvette 10 for a very long
time. In a variant of the invention the overpressure may be applied
impulse-like with a duration of from about 0.75 seconds to about 2
seconds. In combination with the exit opening of the removal tube
system being arranged lower than the bottom 13 of the cuvette 10
e.g. a pressure pulse of the magnitude of 1 bar applied over less
than 1 seconds proves to be sufficient to remove a contact lens 30
from the cuvette 10. The contact lens 30 may then be separated from
the liquid 20 simply by passing the liquid through a sieve or like
element. The liquid 20 flows through the sieve and may be reused;
the contact lens 30 remains on the surface of the sieve and may be
removed therefrom.
[0039] Finally FIG. 5 shows the device 1 with the plate-like lid 2
and the removal tube 3 and the pressure tube 5 being lifted from
the rim 11 of the cuvette 10 exposing the opening 12 of the cuvette
10 again. This is indicated by arrow O. The contact lens has been
removed. There might remain a small amount of liquid 20 inside the
cuvette 10, which can if needed be emptied prior to cleaning of the
cuvette 10.
[0040] In accordance with the invention an overpressure is applied
for the removal of a contact lens from a container, e.g. from a
cuvette for lens inspection, instead of a vacuum. Due to the
overpressure the contact lens together with the liquid contained in
the container are removed through the removal tube. The contact
lens may then simply be separated from the liquid by passing the
liquid through a sieve or the like. Thereafter the contact lens may
be removed from the sieve. The novel method does not require a
vacuum for the removal of the contact lens from the container.
Consequently, complicated and costly vacuum separators are avoided.
The application of an overpressure instead of a vacuum also
overcomes the limitation of the maximum possible pressure
difference. Theoretically any pressure difference to ambient
pressure may be adjusted. Practically the achievable maximum
pressure difference is only limited by the burst strength of the
container and the pressure-tight attachment of the lid thereto.
Thus, the overpressure inside the container may be adjusted to a
magnitude which ascertains that every contact lens is removed from
its respective container. The invention has been explained with
reference to the manufacture of contact lenses. It is to be noted,
that the invention also encompasses the manufacture of other types
of ophthalmic lenses, such as, e.g., intraocular lenses etc. Thus,
the term contact lens must not be read as limiting, but it also
includes these other types of ophthalmic lenses which may be
manufactured in automated manufacture processes.
* * * * *