GB2230352A

GB2230352A - "Contact lens treatment"

Info

Publication number: GB2230352A
Application number: GB9006713A
Authority: GB
Inventors: Tomio Oguma; Masasi Kai; Mikio Yoshihara; Yasuhiro Asoh
Original assignee: Aisin Seiki Co Ltd
Current assignee: Aisin Corp
Priority date: 1989-03-28
Filing date: 1990-03-26
Publication date: 1990-10-17
Anticipated expiration: 2010-03-26
Also published as: DE4009845A1; DE4009845C2; GB2230352B; GB9006713D0

Description

TITLE:

Contact Lens Treatment DESCRIPTION:

The invention relates to contact lens treatment, that is a process and apparatus for cleaning, rinsing, sterilizing and preserving contact lenses.

Contact lenses are generally cleaned in the palm of a hand or on the tip of a finger by dipping a cleaning liquid on the surface, followed by rubbing with the tip of a finger. Dirt, particularly fats contained in tears, on the surface of the contact lens is thereby removed. After cleaning, the contact lens is rinsed with a liquid such as distilled water. Thereafter, the contact lens may be placed with a preserving liquid such as a physiological saline solution in a treatment chamber of the sterilizer having a heater. The preserving liquid is heated, and the contact lens is sterilized by boiling in the preserving liquid. The contact lens thus sterilized can be kept in the preserving liquid until the next use.

The invention provides a contact lens treatment process comprising a cleaning step of stirring a cleaning liquid around the contact lens, and a rinsing step of removing the cleaning liquid from the contact lens. The cleaning step may be carried out at normal temperature or above, and the stirring at from 3000 to 9000 rpm, the contact lens often being floated in the cleaning liquid.

There is preferably included a sterilizing step of stirring a preserving liquid at a uniform sterilizing temperature around the contact lens. The preserving liquid may be stirred intermittently in the sterilizing step.

The invention includes a contact lens treatment apparatus comprising a treatment chamber for accommodating a contact lens, means for stirring a liquid in the treatment chamber, and means for feeding to and discharging from the treatment chamber in sequence a cleaning liquid and a rinsing liquid. The apparatus preferably includes means for feeding to and discharging from the treatment chamber a sterilizing liquid after the rinsing liquid, and a heater for the sterilizing liquid.

The apparatus advantageously comprises tanks for storing the appropriate liquids, first feed pipes connected to the tanks, a second feed pipe connected to the treatment chamber, opening and closing valves disposed in the first feed pipes, and means for operating the valves separately, the bottoms of the tanks being above the top of the treatment chamber so that the liquids can be fed by gravity.

There may be included a container having a plurality of vertical through holes in a top wall and a bottom wall and adapted for accommodating the contact lens fits in the treatment chamber.

A cover for the treatment chamber may have a contact lens holder on a bottom wall thereof, the contact lens holder comprising a forked portion having a space for accommodating the contact lens and holding its periphery As the cleaning liquid, water or soapy water may be used. The contact lens may be either a soft contact lens or a hard contact lens. The liquid flow generated by the stirrer may be horizontal or intersecting the surface of the contact lens which contacts the naked eye, and faces upward or downward.

t 1 -1.

1 As the rinsing liquid, water may be used. The temperature of the rinsing liquid may be as desired, but it is preferable to operate at normal temperature or above to ensure rinsing ability. The liquid flow generated by the stirrer may be brought into contact with the contact lens in the same way as the cleaning liquid.

When heating the preserving liquid, it is preferable for the heater to be immersed in the liquid in order to perform the heating quickly. The number of heaters may be as desired, and their position where it does not obstruct the stirrer. The time of the stirring may be determined so as to heat the perserving liquid uniformly, and the stirring may be performed continuously, temporarily or instantaneously. The speed of the stirring should be determined so as to attain the uniform heating of the preserving liquid.

The treatment chamber should be of a size capable of accommodating a liquid treatment container. The treatment container accommodates the contact lens. A contact lens holder means may be employed instead of the container having the through holes.

The stirrer may be a system in which blades disposed in the treatment are rotated, or a system in which the liquid treatment container for accommodating the contact lens is rotated, or a system in which the liquids are ejected through a nozzle in the treatment chamber. The number of the revolutions of the stirrer blade depends on the volume of the treatment chamber and the nature of the liquids. The number and position of the stirrers may be as desired.

i Drawings Figure 1 is a section through an apparatus for contact lens treatment according to the invention; Figure 2 is a plan of the apparatus of Figure 1 with a cover removed; Figure 3 is a section on a line III-III in Figure 2; Figure 4 is a section of a liquid treatment container in the apparatus of Figure 1; Figure 5 is a plan of a body of the container in Figure 4; Figure 6 is a section on a line VI-VI in Figure 5; Figure 7 is a bottom view of the container body of Figure 5; Figure 8 is a section through a cover of the liquid treatment container; Figure 9 is a bottom view of the cover in Figure 8; Figure 10 is a timing chart specifying the steps of a first preferred process according to the invention; Figure 11 is a plan of the apparatus of Figure 1 with the liquid treatment container removed; Figure 12 is a section through a second apparatus according to the invention; Figure 13 is a section through a third apparatus according to the invention; and Figure 14 is a section on a line A-A in Figure 13.

As shown in Figure 1, the apparatus comprises: a housing 1, a liquid treatment container 2 for accommodating contact lenses W, a stirrer 3 for generating a liquid flow, a heater 4 for sterilizing the contact lenses W by boiling, a feeder 5 for a cleaning liquid, a rinsing liquid and a preserving liquid separately, and a discharge means 6 for the cleaning liquid, the rinsing liquid and the preserving liquid separately.

The housing 1 comprises a body 11 open at the top and having a liquid treatment chamber or cleaning chamber 1') and a cover 12. The cleaning chamber 10 comprises in an upper portion a container chamber 100, for accommodating the liquid treatment container 2, and in a lower portion a stirrer chamber 101 for generating liquid flow. The container chamber 100 comprises three interconnecting arcuate spaces (Figure 2). A number of spaced vertical grooves 110 are formed in the inner walls defining the container chamber 100. The grooves 110 connect the container chamber 100 with the stirrer chamber 101. A hole 101a in the body 11 defines the stirrer chamber 101. A spacer 500 in the hole 101a has the following top surfaces: annular horizontal surfaces 112a, 112b and a truncated conical surface 112 inclined upwards and outwards, and connecting the surfaces 112a and 112b.

A step 113 is formed in the inner walls defining the cleaning chamber 10, and spaced from the surface 112 by a sloping surface 133. A liquid supply hole 114 in the housing 1 communicates with the cleaning chamber 10. An upright passage 115 connects the hole 114 to the stirrer chamber 101. A liquid discharge hole 116 in the bottom. of the cleaning chamber 10 leads to the discharge means 6. An upright passsage 117 connects the stirrer chamber 101 to the discharge hole 116. A sealing groove 118 is formed around the cleaning chamber 10 at the top of the body 11, and a ringshaped seal 119 is fitted therein. A projection 121 is formed integrally on the cover 12 for closing the cleaning chamber 10, and leaves an air space 120 inside. The cover 12 is detachably fixed to the body 11, and the seal 119 is waterproof, so the cleaning chamber 10 is sealed.

In Figure 2, a heater chamber 13 is formed in the cleaning chamber 10. A shallow trough 130 is formed on the top surface of the body 11, and is connected to a relief hole 131 by a down pipe 130a. The relief hole 131 is connected to a discharging tank 062 by a pipe 131a having a valve 132. A shallow trough 134 to the other side of the heater chamber 13 leads to a relief hole 135 by way of a down pipe 134a. The hole 135 is connected to the discharge tank 62 by a pipe 135a having a pressure responsive relief valve 136. The relief holes 131 and 135 are open at the top of the cleaning chamber 10, and serve to discharge air from the cleaning chamber 10. A finger hole 137 communicating with the cleaning chamber 10 is formed opposite the heater chamber 13 on the top of the body 11. A projection 123 (Figure 3) of large volume and a projection 124 of small volume are formed on the inner surface of the cover 12. The projection 124 fits in the finger hole 137, and the projections 123 and 124 reduce the volume of the cleaning chamber 10, thereby saving cleaning, rinsing and preserving liquids.

The liquid treatment container 2 is detachably fixed in the cleaning chamber 10. As shown in Figures 4 to 9, the container 2 comprises a flat body 21, open at the top, having two chambers 20 for accommodating the contact lenses W, and a cover 25 to be fixed on the top openings of the body 21 for covering the chambers 20. The container body 21 is shown in Figures 5 to 7. Small circular holes 211 are formed through the bottom 210 of the lens chambers 20, and radial slits 213 through its side walls 212. A long upright rod-shaped projection 214 is formed integrally at the centre of the body 21 for gripping and lifting with the tips of the fingers. Projections 215 are formed at the outer periphery on the bottom 210 of the body 21. A projection 216 is formed at the centre on the lower surface opposite where the projection 214 is formed. The proj ection 216 reduces the volume of the cleaning chamber 10, thereby saving cleaning, rinsing and preserving liquids. Additionally, as shown in Figure 5, relief holes 217 are formed in the body 21.

As shown in Figures 8 and 9, two engagement portions 250 project from the cover 25. The engagement portions 250 are circular in plan, and fit into the lens chambers 20. Bottom surfaces 250a thereof are formed with a convex spherical surface in conformity with the shape of the contact lenses W. A stop 252 is formed integrally and projects downward at the centre of each engagement portion 250. As shown in Figure 4, fine clearances are formed between the ends of the stops 252 and the bottom 210 of the body 21 when the body 21 is closed by the cover 25. Circular holes 251 are formed through the engagement portions 250. As shown in Figure 8, a cylindrical portion 253 having a through hole 254 is formed at the centre of the cover 25. The through hole 254 engages with the projection 214 of the container body 21.

As can be understood from Figure 4, the projection 214 is held with the fingers at an end 214a when handling the whole liquid treatment container 2. The cylindrical portion 253 is held with the fingers when removing the cover 25 from the body 21. The cover 25 and the body 21 are made from polysulphone resin to preve nt damage to the contact lenses W, and in view of its chemical resistance. As shown in Figure 1, the liquid treatment container 2 is positioned and set in the cleaning chamber 10 by engaging the projections 215 of the container 2 with the step 113 of the body 11. When the container 2 is set in the cleaning chamber 10, a clearance 125 is formed between the container 2 and the bottom of the cover 12, and a clearance 126 is formed between the inner wall of the cleaning chamber 10 and the outer wall of the container 2.

The stirrer 3 (Figure 1) comprises a motor 30, a rotary shaft 32 pressfitted onto a motor shaft 31 and having a liquid path 32a, and a stirrer blade 34 for generating a liquid flow fixed to the rotary shaft 32 by a screw 33. The motor 30 is fixed to the bottom of the housing 11 by screws. A seal 35 is interposed between the outer periphery of the shaft 32 and a hole 11a in the body 11, to prevent liquids from intruding into the motor 30.

As shown in Figure 3, the heater 4 is fixed in the chamber 13 in the body 11 with a screw 41 by way of an installation plate 40. The heater 4 comprises a cylinder 42 of stainless steel containing a wire together with a powder. The cylinder 42 faces a path 138 connecting the cleaning chamber 10 with the heater chamber 13. The heater 4 is immersed in the liquids and connects the chamber 13 with the cleaning chamber 10 so that the liquids in the cleaning chamber 10 are heated.

The feeder 5 adjacent the housing 1 comprises a tank 50 for storing a cleaning liquid such as soapy water, a tank 51 for storing a rinsing liquid such as distilled water, and a tank 52 for storing a preserving liquid such as a physiological saline solution. Three first feed pipes 53 lead away from the tanks 50, 51 and 52 respectively. A second feed pipe 54 connects the first feed pipes 53 and the liquid supplying hole 114 of the body 11. Opening and closing valves 55, 56 and 57 are disposed in the first feed pipes 53. The bottoms of the tanks 50, 51 and 52 are above the top of the liquid treatment container 2 in the cleaning chamber 10 so the liquids are fed by gravity to the container 2.

The discharge means 6 comprises a pipe 60 connected with the liquid discharge hole 116 in the body 11, an opening and closing valve 61 in the pipe 60, and a tank 62 for storing the liquids discharged.

A controller having a microprocessor, is provided in the housing 1 for the operations of the motor 30, the valves L 55, 56, 57 and 132, the relief valve 136 and the heater 4.

In the apparatus, the contact lens treatment process of the invention comprises A a preparation step, B a cleaning step, C a rinsing step, and D a sterilizing step.

A Preparation step The apparatus is charged with suitable liquids in the appropriate tanks. The liquid treatment container 2 is removed from the cleaning chamber 10, and the soft contact lenses W are laid one by one in the lens chamters 20. The convex surface of the contact lens W, i.e. the surface of the contact lens W which does not contact the eye, faces the bottom 210 of the chamber 20. The cover is installed on the body 21. The stops 252 accordingly face the concave surfaces of the lenses W which contact the eye in use. The container 2 with the contact lenses W therein is then set in the cleaning chamber 10 by engaging the projections 215 with the stepped portion 113 of the body 11. The cover 12 is installed on the body 11 to close the chamber 10.

B Cleaning Step A switch (not shown) is turned on the liquid valve 5. The timing of the chart in Figure 10 is then followed:

The valve 55 is opened from T1 to T2 by a timer of the controller. Cleaning liquid is fed to the chamber 10 by way of the pipes 53, 54 and the hole 114. Thus, the cleaning chamber 10 is substantially filled with cleaning liquid during the period from T1 to T2, the valve 132 is opened, and air and eventually cleaning liquid overflow are discharged from the chamber 10 through the relief hole 131 and the discharge pipe 131a. The level of the liquid remains constant in the chamber 10. The valve 61 of the discharge means 6 is closed during the period, so no cleaning liquid flowing into the chamber 10 is discharged through the pipe 60._ When the chamber 10 has filled with the cleaning liquid, the liquid flows into the lens chambers 20 through the holes 211, slits 213 and holes 251, and the contact lenses W in the container 2 are immersed in the cleaning liquid.

As shown in the timing chart of Figure 10, the motor 30 is actuated to rotate by the timer of the controller from T2 to T3. The motor shaft 31, the shaft 32, and the stirrer blade 34 thus rotate at a speed of approximately 8000 rpm. As a result, the cleaning liquid in the cleaning chamber 10 is stirred, and becomes a high speed liquid flow. The flow is transmitted outward by centrifugal force, reaches the chamber 100 by way of the stirrer chamber 101, mainly guided by the tapered surfaces 112 and 133, becomes turbulent, and goes into the lens chambers 20. Since the vertical grooves 110 which connect the container chamber 100 with the stirrer chamber 101 are formed in the body 11, the cleaning liquid is allowed to flow into the stirrer chamber 101. Any dirt adhering to the surfaces of -the contact lenses W is removed by the liquid flow.

is It is believed that the liquid flow into the lens chambers 20 goes out of the container 2 mainly through the slits 213 near the stirrer blade 34, and that the flow returns to the chamber 101 mainly. through the relief holes 217. This is because the cleaning liquid above the blade 34 is sucked in toward the blade 34 by its revolution. The liquid flow thus circulates around the contact lenses W at a high speed when the motor 30 is running. The dirt adhering to the contact lenses W removed most effectively because fine bubbles of air are contained in the liquid.

1 The rotation of the motor 30 is made to stop at the time T3. During the period from T3 to T4, the opening and closing valves 61 and 132 are turned on by the timer, and so are opened. As a result, the cleaning liquid in the chamber 10 is discharged into the tank 62 through the hole 116 and the pipe 60, and the cleaning step is finished. At this moment, the cleaning liquid has flowed down along the tapered surface 112 of the chamber 10, and has been discharged.

C Rinsing step Since the opening and closing valve 56 for the rinsing liquid tank 51 as well as the opening and closing valve 132 are turned on by the timer, and are opened from the time T4 to T5, the rinsing liquid in the tank 51 drains by gravity and is fed to the chamber 10 through the pipes 53 and 54. The chamber 10 is accordingly filled up with the rinsing liquid. Then, the motor 30 is rotated by the timer in the period between T5 and T6. The stirrer blade 34 is rotated and a turbulent liquid flow of rinsing liquid is generated in the chamber 10. Then the liquid flow passes through the slits 213 and the like of the container 2, and into the lens chambers 20. Thus, the rinsing of the contact lenses W is carried out. The opening and closing valves 61 as well as the opening and closing valve 132 are turned on by the timer, and they are open during the period from T6 to T7. The rinsing liquid in the chamber 10 is consequently discharged into the tank 62 through the hole 116 and pipe 60. The cleaning step is thus finished.

D Sterilizing step Since the opening and closing valve 57 for the preserving liquid tank 52 as well as the opening and closing valve 132 are turned on by the timer, and opened from T7 to T8, the preserving liquid in the preserving tank 51 drains by gravity and is fed to the chamber 10 through the pipes 53 and 54. The chamber 10 is accordingly filled with preserving liquid. At the time T8, the heater 4 is turned on. The he-at generated by the heater 4 is transferred to the preserving liquid in the chamber 10, and the preserving liquid is heated in the chamber 10. As can be seen from Figure 3, the thus heated preserving liquid ascends, and flows into the chamber 10 by way of the liquid path 127 formed between the projection 123 and the heater 4. At the same time, preserving liquid at low temperature adjacent the bottom of the chamber 10 is believed to flow into the heater chamber 13 by way of the path 138. As a result, the preserving liquid in the cleaning chamber 10 is heated and boiled, thereby sterilizing the contact lenses W. The preserving liquid is not only heated by the heater 4, but also stirred by the stirrer blade 34 at intervals during the period from the time T8 to T9. Thus the preserving liquid in the chamber 10 is heated uniformly.

One might think that the liquid remaining in the supplying hole 114 and the discharge hole 116 might not be heated effectively, and there might be fears of insufficient disinfection of the liquid and the contact lenses W. However since the apparatus has the vertical communication passages 115 and 117, the hot preserving liquid ascends to the top of the chamber 10 by convection and gradually flows into the supply hole 114 and discharging holes 116, pushing the liquid remaining therein out to the chamber 10. Thus, it is expected that the whole preserving liquid in the chamber 10 can be heated to the boiling temperature uniformly and effectively.

As shown in Figure 10, the sterilizing by boiling continues until the time T9. After its completion, the contact lenses W are usually left in the container 2 until the next used. Before using the contact lenses W, the cover 12 of the housing 1 is removed, and the 1 liquid treatment container 2 is taken out. Then, the cover 25 is removed from the body 21, and the contact lenses W are taken out. When the container 2 is taken out of the chamber 10, the preserving liquid in the container 2 discharges itself through holes 211, slits 213 and holes 251.

The pressure in the space above the preserving liquid in the chamber 10 does not increase as the preserving liquid evaporates by heating in the sterilizing step because the pressure responsive relief valve 136 opens agains the force of its spring when the pressure in -t-he space above the preserving liquid exceeds a predetermined value, the air above the preserving liquid is relieved, and an excessive pressure increment is thus avoided. Accordingly, the housing 1 and its internal mechanism are not damaged.

The cleaning liquid, the rinsing liquid and the preserving liquid are fed to the chamber 10 separately and they are discharged separately. The four steps of cleaning, rinsing, sterilizing and preserving are carried out automatically in a single chamber 10. The contact lenses are not moved from one apparatus to another, or from one location to another in an apparatus, and so they are not held with the fingers. Therefore, dirt from the fingers does not adhere to the contact lenses.

In addition, the cover 25 has the stops 252 formed integrally on the bottom, so the contact lenses W in the lens chambers 20 are prevented from moving or displacement in the cleaning, rinsing, and sterilizing steps. Soft type contact lenses W might be deformed into curls due to flexibility and swellability, but such a deformation is less likely because the stops 250 also prevent the contact lenses W from curling up. Likewise, the stops 250 help prevent the contact lenses W from being deformed and damaged by movement in the accommodating chambers 20. This all tends to prolong the life of the contact lenses W.

Further, the liquid treatment container body 21 has the radial slits 213. The arrangement of the slits 213 helps bring the liquid into contact horizontally with the contact lenses W in the lens chambers 20. Therefore, the dirt adhering on the contact lenses W is cleaned off to an extremely high degree. Additionally, the container 2 has the holes 251 above the contact lenses W and the holes 211 below the contact lenses W. The liquid thus pushes the contact lenses W from the top and the bottom, and causes them to float. The contact lenses W are thus f ree f rom close contact either with the bottom 210 of the lens chambers 20 or with the bottom 250a of the engagement portions 250 of the cover 25.

Figure 2 is similar to Figure 1, so only the differences will be described, and the same reference numbers are used to designate the corresponding components. A carrying case 7 having no through holes is employed instead of the container 2. The case 7 comprises a body 70 having a lens accommodating chamber, and a cover 71. After cleaning the contact lenses W with the tip of the finger in the manner of the prior art, the contact lenses W are accommodated togetner with the preserving liquid in the bodies 70, and then the covers 71 are sealed on the bodies 70. The cases 7 are then placed in the chamber 2. Then the heater 4 heats the water in the chamber 10 as well as the preserving liquid in the cases 7, thereby sterilizing the contact lenses W by boiling. While carrying out the sterilizing of the contact lens W by boiling, the stirrer blade 34 is rotated, and so all the water is uniformly heated in the chamber 10 to the sterilizing temperature.

Figure 13 also is similar to Figure 1, and so may similarly briefly be described. A lens holder 8 for the contact lenses W in the chamber 10 is provided instead of the liquid treatment container 2. A pair of lens holders 8 is disposed on the bottom surface of a cover 12a, and extends into the chamber 10 when the cover 12a is installed on the housing body 11. Each of the lens holders 8 has a forked portion 81, and the forked portion 81 has a space 82 for accommodating the contact lens W.

The contact lens W is held at the periphery by the forked portion 81. The holder 8 thus holds the contact lens W securely. There are accordingly no fears for damaged or deformed contact lenses W when the contact lenses W are moved by the liquid flows. In addition, since the contact lenses W are held by the holder 8 at the periphery, the liquid flows act directly on the contact lenses W. The effect, i.e. the cleaning, rinsing and sterilizing effects, are thus enhanced. Moreover, since the pair of the lens holders 8 is disposed on the bottom of the cover 12a, they are removed when the cover 12a is taken off the housing body 11. The contact lenses W can be simply put into the spaces 82 of the thus-exposed lens holders 8.

Claims

CLAIMS:

1. A contact lens treatment process comprising a cleaning step of stirring a cleaning liquid around the contact lens, and a rinsing step of removing the cleaning liquid from the contact lens.

2. A process according to claim 1, wherein the cleaning step is carried out at normal temperatureor above.

3. A process according to claim 1 or claim 2, wherein the stirring is carried out at from 3000 to 9000 rpm.

4. A process according to any preceding claim, wherein the contact lens is floated in thecleaning liquid.

5. A process according to any preceding claim comprising a sterilizing step of stirring apreserving liquid at a uniform temperature around the contact lens.

6. A process according to claim 5, wherein the preserving liquid is stirred intermittently in the sterilizing step.

7. A contact lens treatment process substantially as herein described with reference to the drawings.

8. A contact lens treatment apparatus comprising a treatment chamber for accommodating a contact lens, means for stirring a liquid in the treatment chamber, and means for feeding to and discharging from the treatment chamber in sequence a cleaning liquid and a rinsing liquid.

9.

Apparatus according to claim 8 comprising k - means for feeding to and discharging from the treatment chamber a sterilizing liquid after the rinsing liquid.

10. Apparatus according to claim 9 comprising a heater for the sterilizing liquid.

11. Apparatus according to any of claims 8 to 10 comprising tanks for storing the appropriate liquids, first feed pipes connected to the tanks, a second feed pipe connected to the treatment chamber, opening and closing valves disposed in the first feed pipes, and means for operating the valves separately, the bottoms of the tanks being above the top of the treatment chamber so that the liquids can be fed by gravity.

12. Apparatus according to claim 11, wherein a container having a plurality of vertical through holes in a top wall and a bottom wall and adapted for accommodating the contact lens fits in the treatment chamber.

13. Apparatus according to any of claims 8 to 12, wherein a cover for the treatment chamber has a contact lens holder on a bottom wall thereof, the contact lens holder comprising a forked portion having a space for accommodating the contact lens and holding its periphery.

14. A contact lens treatment apparatus substantially as herein described with reference to Figures 1 to 11 of the drawings, or as modified by Figure 12 or Figures 13 and 14.

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