US3782045A

US3782045A - Contact lens polishing system

Info

Publication number: US3782045A
Application number: US00213395A
Authority: US
Inventors: M Kanda
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-12-29
Filing date: 1971-12-29
Publication date: 1974-01-01
Anticipated expiration: 1991-01-01

Abstract

A polishing solution recirculating system for use with contact lens polishing machines wherein lenses held by separate holders are brought into contact with a wetted surface polishing element disposed on a rotating spindle with additional polishing solution being applied to the wetted surface as the holder is rocked to alternate angular positions of contact with respect to said spindle for exposing further areas of the lenses to polishing action and wherein nozzles of a distributor manifold are mounted for movement with a rocking mechanism to keep the nozzles in operative position for polishing solution application at all reciprocal positions for said holders. A splash tray is disposed about the spindles and connected to a sump whereby the polishing solution is collected for intermixture and recirculation by a pump disposed in the sump and having its pressure side connected to said manifold.

Description

United States Patent [1 1 Kanda flan. 1,1974

[ CONTACT LENS POLISHING SYSTEM [76] Inventor: Masami Kanda, 1515 W. 48th Ave.,

Denver, Colo. 80221 [22] Filed: Dec. 29, 1971 [21] Appl. No.: 213,395

[52] US. Cl. 51/124 L, 51/263 [51] Int. Cl 1324b 7/22 [58] Field of Search 51/124 L, 263, 234,

3,032,936 5/1962 Voice 51/124 L 3,037,331 6/1962 Dirprey et al.. 51/124 L 3.094.814 6/1963 Barke ct a1. 51/263 X 3,400,494 9/1968 Seitz 51/263 X Primary Examiner-Harold D. Whitehead Assistant Examiner-Nicholas P. Godici Attorney-C. B. Messenger [5 7] ABSTRACT A polishing solution recirculating system for use with contact lens polishing machines wherein lenses held by separate holders are brought into contact with a wetted surface polishing element disposed on a rotating spindle with additional polishing solution being applied to the wetted surface as the holder is rocked to alternate angular positions of contact with respect to said spindle for exposing further areas of the lenses to polishing action and wherein nozzles of a distributor manifold are mounted for movement with a rocking mechanism to keep the nozzles in operative position for polishing solution application at all reciprocal positions for said holders. A splash tray is disposed about the spindles and connected to a sump whereby the polishing solution is collected for intermixture and recirculation by a pump disposed in the sump and having its pressure side connected to said manifold.

4 Claims, 1 Drawing Figure PATENTED H974 3 782.0 5

V INVENTOR.

WAS/I m/ 142N019 BY 47- TO away BACKGROUND OF THE INVENTION Several different machines have previously been de- DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the invention is shown in veloped for polishing contact lens surfaces. Though it 5 FIG. 1. In this illustration the invention is shown as an at least has been outwardly recognized that a fine polish is desirable for both the inner and outer surfaces of contact lenses to provide better optical results and further to minimize irritation of the eye surfaces, previous manufacturers have in general failed to recognize the great amount of hand operations or personal attendance required in the use of their machines. In polishing operations the polishing solution, which is a mixture of water or other solvent and an abrasive powder, must be kept on the surface being polished. The wetted net, gauze or felt surface of a polishing cover is brought into contact with the surface of the lens, and thereafter the polishing solution is used to keep the polishing cover wet to avoid burning or scratching of the lens. With previous equipment this wetted cover was kept moist by hand applications of the polishing solution. The attendant in charge of the polishing operation usually had to be in constant attendance so that minor quantities of solution could be hand dipped with a brush and applied to wet the cover. Though multiple spindle machines have been used so that a plurality of lenses could be ground simultaneously and though these many spindles could be attended by a single operator, the hand labor and constant attendence characteristics are burdensome. Further, due to the hand application of polishing solution, varied results could be and were obtained. Even where properly attended and manipulated, the tendency to cut short the polishing time sometimesresulted in the release of lenses having irritating or inadequate surface characteristics.

SUMMARY OF THE INVENTION The present invention provides a system for applying and recirculating polishing solutions so that polishing elements brought into contact with the lens surfaces will be constantly wetted with polishing solution. The polishing solution is carried by a manifold to be distributed by nozzles that are directed at the interface between the lens surface being polished and the polishing element. Since the orientation of such interface changes as lens holders of the polisher system are moved reciprocally in a rocking motion, the manifold and the nozzles themselves are mounted for conjoint movement therewith. With the motion of the manifold and nozzles coordinated with the motion of the polishing elements, even wetting of the polish cover and of the lens surface being polished is assured. A splash shield or collector tray is disposed about the periphery of all polishing spindles so that solution thrown from the spindles and the polishing cover itself will be constrained and collected for return to a sump. The solution in the sump is stirred and agitated by action of a pump, and it is subsequently pressurized by the pump for delivery to the manifold. A reciprocal drive mechanism is used to oscillate the follower system of the polishing equipment and the manifold and distributor nozzles in a manner that may be regulated and coordinated to provide varying results.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a partial front elevation showing operative elements of the invention.

addition or attachment for use with a conventional type of contact lens polishing equipment. Present equipment configurations include a cabinet 12 having a bench top 13 and supports 14 and 15 extended thereabove. A plurality of drive shafts (not shown) extend upwardly through the bench top 13 to rotate the polishing chucks l6, l7, 18. A motor and gear drive mechanism (not shown) is included within the cabinet 12 to rotate a plurality of shafts and the spindle-receiving chucks 16-18 therefor. Each of the chucks is similar to the drive chuck of an electric drill or similar apparatus to provide adjustable jaws that are adapted to hold or release

lens mounting spindles

26, 27, 28. These spindles are provided with various spherical or other contoured convex shapes at the upper end so that the spindles will conform to the concave inner curvature of contact lenses, such as the lens 21, for polishing purposes. Other spindles having an upwardly open concave surface are adapted to conform to the exterior or convex surface of the contact lens. The spindles 26- 28 are themselves covered by

polishing covers

36, 37, 38 that are of material that can be wetted. Net, felt, gauze or other cloth type covers have been successfully used.

In addition to providing the drive mechanism for rotation of the spindles, present equipment also includes mechanism for holding the lenses in position of contact with the spindle supported polishing cover. A type of holder mount is shown in this preferred embodiment where the end supports 14 and 15 provide bearing surfaces 24 and 25 for the reception of and reciprocal support of a rocker shaft 31. A plurality of pivotally mounted followers 32 are disposed on rocker shaft 31 for angular movement with respect thereto as the followers rotate about their mount pivots 33. A pin 34 is provided at each follower. These pins 34 are free to reciprocate in their followers and are usually urged by a biasing spring element (not shown) in the downwardly extending direction. At the lower end of each holder pin 34 a lens holder 35 is provided. These holders have a lower resilient recess for closely holding contact lenses placed therein. With this arrangement the biasing springs tend to hold the pins and holders down against the polishing covers of the spindles 26-28. Usually the spring pressure transmitted by the holder pins 34 can be changed to modify the pressure applied against the lens. With the described arrangement reciprocal movement of the rocker shaft 31 in bearings 24 and 25 will power a rocking motion of the followers 32 and of all the lens holders 35 mounted thereon. With such rocking motion all surfaces of the lens can be given an equal polish.

The features so far described are incorporated in machines now in use. In connection with the use of these machines an operator or attendant must manually wet the polishing cover so that the lenses will not be burned or scratched. Usually a supply of polishing solution is provided, and such solution is hand applied by the dipping and application of a brush full of liquid at a time. Since the polish covers tend to dry out quite readily, near constant attendance of an operator is required. Where machines having eight or more spindles are being operated, the attendant can be quite busily engaged with the necessary moistening operations. in order to eliminate the requirement for constant attendance and also to provide a more uniform wetting of the polish covers and lenses, an embodiment of the present invention has been successfully built and operated. An improved polishing result is obtained by the new apparatus in which the polishing solution is constantly and mechanically applied.

The illustrated embodiment of the invention provides a tank or sump 41 that is mounted on the cabinet 12. This sump is adapted to receive a substantial quantity of polishing solution 42. The polishing solution, which is usually a combination of a solvent, such as water, and a soft powdered abrasive, is placed in the sump 41. A pump 43 is used to take up and circulate the polishing solution. Pressurized solution from the pump is delivered by a flexible tube 44 to a manifold 46 that is supported on and moves with the rocker shaft 31. A plurality of take-offs 47 are provided so that polishing solution is delivered to all the distributor nozzles 48. Preferably a self-supporting type of flexible pipe is used between the take-offs 47 and the nozzles 48. These pipes 49 can then be bent to a position for directing a spray of solution at the polishing covers and lenses. With the manifold and nozzles being mounted on the rocking mechanism the nozzles will stay in position for direct spray application of the polishing solution for all alternate positions of the lens holder components. A substantial spray of solution is provided by the pump, and accordingly, the lens and polishing covers are uniformly wetted.

The spray application and the rotational speed of the spindles cause substantial splashing, and accordingly, a splash tray 51 is provided. This splash or collector tray has a sloping bottom 52 disposed above the bench top 13 and a plurality of end and side walls. All of the polishing solution that is thrown off is then collected at the tray bottom 52 for redelivery by a pipe 53 to the sump 4]. A filter 54 is disposed in the line for removal of large particles and chips so the polishing solution will not later scratch the lenses being polished. The return flow of fluid and the pumping operations serve to stir and intermix the solution 42 in the sump so that any settling tendency for the abrasive components will be countered. The abrasive is thus kept in suspension for introduction at the elevated intake 56 of the pump 43. Such elevated intake prevents the ingestion of substantial quantities of abrasive component when the polishing operations are initiated after a long period of interruption.

While only three spindles are shown by the present illustration, it should be understood that the polishing machine could and may have eight, twelve, sixteen or any other number of polishing spindles in aligned positions. Where additional spindles are used, the manifold 46 is extended, and additional take-offs and pipes are' provided for each spindle. The additional nozzles 48 are again positioned for directing the sprayed solution at the polish covers and the lenses so that all polishing will be done in the presence of solution. When the apparatus is to be used, the pump will ordinarily be started ahead of time so that the solution will prewet all of the polish covers. Further, the initial circulation of the solution will tend to remix any settled abrasive compound so that the polishing solution being applied to the lenses will be uniform when operation of the spindle rotation mechanisms and the holder drive components is initiated.

Use of the present embodiment of the invention has provided an improved polishing result. The even application of polishing solution contributes to such improved result even where equivalent polishing times are being considered. Actually, however, the elimination of hand operations and the consequent necessity for constant operator attendance permits the polishing operations to be continued for an extended period of time. Where the hand labor is eliminated, a more desirable and extensive polishing cycle can be used with less overall expense. With the resulting finer polish on the lens surfaces, improved optical results are obtained, and there is also an improvement in user compatibility. Both better vision and less irritation characteristics are observed.

In addition to the solution application mechanism, the present embodiment of the invention provides a double acting air cylinder 61 that is interconnected with the rocker shaft 31 to reciprocally drive such shaft. With cylinder 61 mounted on an extension 62 from support 15 and with

air lines

63 and 64 connected to the cylinder 61, the shaft 31 is reciprocated. Regulation of the valve 66 provides flow control for the air. Accordingly, the drive speed for the rocker shaft 31 may be changed or modified. Usually a realtively slow rocking motion is desirable. Whether slow or fast return cycles are used, the distributor nozzles will at all times be operationally positioned to keep the polish covers and lens surfaces wet.

I claim:

1. A contact lens polishing device of the type providing a plurality of lens polishing spindles and mechanisms for rotating the same comprising, polishing covers on each of said spindles, contact lens holders for positioning adjacent each of the spindles and providing means to receive and hold the lens surfaces of lenses in position for contact with said polish covers, a rocker mechanism including a reciprocally moving shaft, pivot means disposed at angular positions with respect to the axis of said shaft providing separate mountings for said lens holders whereby the angular position of said lens holders and lenses with respect to the axis of said spindles may be pivotally changed, a supply of polishing solution, a manifold mounted to move reciprocally with the shaft of said rocker mechanism for conveying said solution to positions adjacent each said spindle, a plurality of spray nozzles supported by said manifold for reciprocal movement therewith with each nozzle being independently directed to spray solution on an individual cover and the lens surface being polished thereby, pump means for delivering polishing solution from said supply to said manifold and nozzles, a collector tray disposed about the plurality of spindles for the collection of expelled solution, and a return circuit for redelivery of said solution to the supply.

2. A device as set forth in claim 1 wherein said return circuit is inclusive of a tilted bottom for said collector tray and further comprising a filter in said return circuit for the removal of oversize particulate matter from said polishing solution.

3. A device as set forth in claim 1 and further comprising a sump for said device to receive and hold said supply of polishing solution and wherein the polishing solution is inclusive of powdered abrasive matter normally kept in suspension by action of said pump and from said return circuit is disposed in said sump and at an elevation below the elevation for the intake of said pump whereby said powdered abrasive is more efficiently kept in suspension within said sump.

Claims

3. A device as set forth in claim 1 and further comprising a sump for said device to receive and hold said supply of polishing solution and wherein the polishing solution is inclusive of powdered abrasive matter normally kept in suspension by action of said pump and wherein the intake for said pump is disposed in elevated position in said supply to avoid ingestion of settled concentrations of said abrasive after periods of nonuse.

4. A device as set forth in claim 3 wherein the outlet from said return circuit is disposed in said sump and at an elevation below the elevation for the intake of said pump whereby said powdered abrasive is more efficiently kept in suspension within said sump.