Contact lens holding device

Abstract: A contact lens holding device (10) for use in a disinfecting system (48) having a single-molded piece, the piece having a dividing portion (12) having first (14) and second (16) surfaces, a first basket portion (20) integrally attached to and capable of folding into closable engagement with the first surface (14) of the dividing portion to form a first lens enclosure (28), and a second basket portion (30) integrally attached to and capable of folding into closable engagement with the second surface (16) of the dividing portion to form a second lens enclosure (42), the dividing portion (12), first basket portion (20) and second basket portion (30) lying on a substantially single plane when in unfolded configuration.

Description: The present invention relates to the field of contact lenses, and more particularly to a contact lens holding device and to a system for disinfecting contact lenses according to the preamble of the respective independent patent claim. One method of disinfecting contact lenses involves placing each lens in a solution containing hydrogen peroxide, and then neutralizing the solution using a catalyst. The method is typically performed by placing the lenses in a complicated system, in which a multipiece basket assemby is placed in a cup-like container holding the disinfecting solution and catalyst. The system and method is described in more detail in U.S. Patent No. 4,011,941 to Parsons. Another system for disinfecting contact lenses, and in particular a contact lens holding device of such a system, is disclosed in US-A-4,890,729. The contact lens holding device disclosed in this reference is a piece that can be molded in a single molding step. It comprises a base portion having two concave lens receiving portions and two cover members hingedly attached to the said base portion. Each hingedly attached cover member can be brought into closable engagement with the base portion to enclose a contact lens that has been placed into the respective concave lens receiving portion prior to closing the said lens receiving portion. The cover members are each attached to the base portion by means of an over-center hinge and two stabilizing hinges preventing the cover member from twisting. Other known contact lens disinfection systems consist of a number of separately molded parts which have been manually pieced together. Typically, a pair of individually molded basket portions are snap-fitted to a main portion or base portion, which in turn is attached by a stem portion to the cap of the disinfection container. Such a disinfection system and a respective contact lens holding device are disclosed, for example, in GB-A-2,034,497, which has been chosen to form the basis for the preamble of the independent claim directed to the contact lens holding device. The contact lens holding device disclosed in this reference comprises a base portion having two convex surfaces facing in opposite directions and a surrounding side-edge. Pins are provided on the side-edge of the base portion. The lens baskets are molded as separate pieces which have to be attached to the base portion during assembly of the contact lens holding device. Attachment of the basket portions to the base portion is achieved by means of two pairs of resilient, bifurcated projections or fingers each of the basket portions is provided with. The resilient, bifurcated projections or fingers are arranged to be releasably engaged over two respective pins provided on the side-edge of the base portion. After assembly of the holding device, a contact lens can be placed with its concave surface onto one of the convex surfaces of the base portion and the respective contact lens basket can be brouhgt into closable engagment with the base portion thereby enclosing the contact lens between the respective convex surface and the contact lens basket. The second contact lens in then placed onto the second convex surface of the base portion and the respective contact lens basket is then closed in the same manner as described above. Such a complicated assembly results in increased manufacturing time and the need for a large amount of manual labor, often compounded by assembly line down time caused by a shortage of an individual component. In addition, because disinfection systems are often handled roughly during shipping, on store shelves or in travelling cases, handbags or such, the snap-fitted parts of the basket assemblies often break apart. The result is a fragile, yet expensive assembly which is not well suited for use in a low cost, high volume disposable disinfection system. Therefore, there exists a need for a contact lens holding device which is inexpensive to manufacture, which minimizes or eliminates assembly problems, and which is of sturdy construction. Such device would enable the manufacture of a practical, low cost disposable disinfection system, which to date has not been available. The above mentioned problems of prior art contact lens holding devices and of contact lens disinfection systems, respectively, are overcome by a contact lens holding device and by a contact lens disinfection system as specified in the independent patent claims. Advantageous embodiments are specified in the dependent claims. The contact lens holding device of the present invention comprises a single-molded piece which has a dividing portion having first and second convex surfaces facing in opposite directions. The dividing portion has a surrounding side-edge to which first and second basket portions are integrally attached by means of first and second living hinges, wherein the first and second living hinges are the only hinges between the side-edge of the dividing portion and the first and second basket portions. The basket portions are capable of folding into closable engagement with the first and second convex surfaces of the dividing portion to form first and second lens enclosures. When the device is in unfolded configuration, the dividing portion and the first and second basket portions lie substantially in a single plane. This provides the ability to mold the device as a single piece on a single-molding plane, thereby greatly reducing the cost of manufacture and eliminating the above-mentioned problems associated with multiple component assemblies. In fact, unlike prior assemblies, the integral nature of the present device allows the manufacturer to eliminate assembling costs by placing the device in unfolded form within packages of disinfecting solution. Also, the elimination of snap-fitting parts results in a contact lens holding device which is less likely to break. For at least the above reasons, the present invention allows for an economically practical disposable contact lens disinfecting system. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view of a contact lens holding device according to the present invention in a partially folded configuration. Fig. 2 is a top view of a contact lens holding device according to the present invention in an unfolded configuration. Fig. 3 is a side view of a contact lens holding device according to the present invention in an unfolded configuration taken along line B-B. Fig. 4 is a side elevation view of a contact lens holding device according to the present invention in a use in a disinfecting system. Fig. 5 is front elevation view of a contact lens holding device according to the present invention in a use in a disinfecting system. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a contact lens holding device 10 which is a single-molded piece, and which is well suited for use as part of a disposable contact lens disinfecting system 48. Fig. 1 shows the contact lens holding device 10 of the present invention in a partially folded configuration. Figs. 2 and 3 show the device 10 in unfolded configuration, such as exists when the device 10 is removed from a mold. The device 10 includes a disc-like dividing portion 12 having a first surface 14 and a second surface 16 separated by a side edge 18. Preferably, the first and second surfaces 14, 16 are each convex to coincide with the concave surface of a contact lens and have a plurality of holes for allowing passage of disinfecting solution through its body. A first basket portion 20 is integrally attached to the side edge 18 of the dividing portion 12 by a first living hinge 22. The first basket portion 20 has a concave interior wall 24 and an opening 26. The first basket portion 20 is capable of being folded, in the direction of its open side 26, into closable engagement with the first surface 14 of the dividing portion 12 to form a first lens enclosure 28. The first basket portion 20 preferrably has holes for allowing disinfecting solution to pass through to a lens in the first enclosure 28. Likewise, a second basket portion 30 has a concave interior surface 38 and is integrally attached to the side edge 18 of the dividing portion 12 by a second living hinge 32 at a position other than that occupied by the first basket member (and stem 34, if present). A first hook-like latch 36 is provided on the first basket portion 20 at a position opposite the first living hinge 22 for securing the attachment of the first basket portion 20 to the first surface 14 when the device 10 is in folded position. The second basket portion 30 is capable of being folded, in the direction of its open side 40, into closable engagement with the second surface 16 of the dividing portion 12 to form a second lens enclosure 42. The second basket portion 30 also preferrably has holes for allowing disinfecting solution to pass through to a lens in the second enclosure 42. A second hook-like latch 44 is provided on the second basket portion 30 at a position opposite the second living hinge 32 for securing the attachment of the second basket portion 30 to the second surface 16 when the device 10 is in folded position. The first living hinge 22 allows the first basket portion 20 to fold towards and upon the first surface 14 of the dividing portion 12. Likewise, the second living hinge 32 allows the second basket portion 30 to fold towards and upon the second surface 16 of the dividing portion 12. Each living hinge 22,32 preferably is formed by a furrow or channel 46 extending between the length of attachment of its respective basket portion 30, 20 and the dividing portion 12 over which the basket portion folds. For this reason, the device 10 should be made of a material which is strong enough to withstand the disinfection process and everyday misuse, but flexible enough to allow folding at the living hinges 22,32 and engagement by the latches 36,44. Polypropylene and polyethylene are examples of materials which meet the needs of the invention. As illustrated in Figs. 2 and 3, when the device 10 of the present invention is in unfolded position, the dividing portion 12, the first basket portion 20, the second basket portion 30, both living hinges 22,32, and the stem 34 if present, all lie in substantially the same plane. This enables the device 10 to be manufactured in a single molding step, and provides the advantages described above. Means for maintaining the device 10 in stable position within a disinfection system 48 may also be provided. The stabilizing means may be a stem 34 attached at a first end to the dividing portion 12 at a position along the side edge 18 of the dividing portion 12 not occupied by either of the basket portions 20,30 and having means for attaching to the cap 52 or other stabilizing portion of a disinfecting system container 34 at the opposite end. The longitudinal axis of the stem 34 is preferably in an identical plane with the longitudinal axis of the dividing portion 12. There must also be sufficient space between the stem 34 and the basket portions 20,30 to allow folding of the device 10 without interference. Figs. 4 and 5 show the device 10 in completely folded position and in use within a disinfecting system 48. The device 10 is inside a disinfecting cup 50 and is attached by its stem 34 to a container cap 52 having a vent 54. A catalytic disc 56 for neutralizing hydrogen peroxide is provided below the device 10. A first contact lens is located inside the first enclosure and a second contact lens is located inside the second enclosure 42. Once the disinfecting process is completed, the device 10 is removed from the cup 50, the basket portions 20,30 moved back into substantially unfolded position, and the lenses removed.

Claims: A contact lens holding device comprising a dividing portion (12) having a surrounding side-edge (18) and first and second convex surfaces (14,16), a first basket portion (20) attached to the dividing portion (12) and capable of folding into closable engagement with the first convex surface (14) of the dividing portion (12) to form a first lens enclosure (28), and a second basket portion (30) attached to the dividing portion (12) and capable of folding into closable engagement with the second convex surface (16) of the dividing portion (12) to form a second lens enclosure (42), said first and second convex surfaces (14,16) of said dividing portion (12) facing in opposite directions, characterized in that the contact lens holding device comprises a single-molded piece (10), that the first basket portion (20) is attached to the side-edge (18) of the dividing portion (12) by means of a first living hinge (22) integrally formed with the single-molded piece (10), and in that the second basket portion (30) is attached to the side-edge (18) of the dividing portion (12) by means of a second living hinge (32) integrally formed with the single-molded piece (10), whereby said dividing portion (12), first basket portion (20) and second basket portion (30) lie in a substantially single plane when in unfolded configuration, and wherein the first and second living hinges (22,32) are the only hinges between said side-edge (18) of the dividing portion (12) and said first and second basket portions (20,30). A contact lens holding device according to claim 1, characterized in that means (36,44) are provided for engagably closing the first and second basket portions (20,30) to the dividing portion (12). A system for disinfecting contact lenses using a disinfecting solution, said system comprising a container for holding the disinfecting solution, means for sealing the container, and a contact lens holding device for holding a contact lens in position inside the container during disinfection, characterized in that the contact lens holding device is a device according to any one of the preceding claims. A system for disinfecting contact lenses according to claim 3, characterized in that the disinfecting solution comprises hydrogen peroxide, and that the system further comprises a catalyst for neutralizing the hydrogen peroxide.

Inventors: ALVORD LARRY A, ALVORD, LARRY A.
Applicants: CIBA GEIGY AG, NOVARTIS AG
Application year: 1993
Main classification: A45C11
IPC codes: A45C11, A61L2, G02C13, A61F2