US1456673A - Blocking machine - Google Patents

Description

May 29, 1923.

INVENTOR F a G I GILBERT S. DEY

BY H1 Hf a w 964% ATTORNEYS G. S. DEY

BLOCKING MACHINE Filed Nov. 10 1919 4 Sheets-$heet 2 INVENTOR G/LBERT s 05) BY F I G. 11 m ATTORNEYS May 29, 1923.

' G. s. DEY

BLOCKING MACHINE Filed Nov. 10 1919 4 MHwft x Sheets-Sheet 3 INVENTOR G/LBERTS. DE Y ATTORNEYS May 29, 1923.

G. S. DEY

BLOCKING MACHINE Filed Nov. 10 1919 4 Sheets-Sheet 4 Patented May 29, I923.

UNITED 'sra'rss RAT-ENT 1 orrlcs.

eitnnar s. DEY, or SOUTHBRIDGE, MASSACHUSETTS, ASSIGNOR r AMERICAN OPTICAL COMPANY, or sournsarncn, massacnnsnms, A VOLUNTARY ASSO- CIATION OF MASSACHUSETTS.

BLOCKING MACHINE. 4

Application filed November 10, 1919. Serial No. 337,090.

To all whom it may concern .Be it known that I, GILBERT 15. DnY, of Southbiidge, in the county of \Vorcester and State 'of Massachusetts, have invented cer- 5 tain new and useful Improvements in Blocking'Machines, of which the following is a specification. This invention relates to improvements in blocking machines, and has particular reference to a machine adapted for use in the accurate blocking of ophthalmic lenses.

1 One of the leading objects of the present invention is the orovision of a novel and improved construction of machine which will satisfactorily serve to automatically accurately blockor position lenses on retaining mounts for subsequent grinding. A further object of the present invention "is the provision of an improved substantially automatically operating blocking machine which shall so mount the lens on its block as to reduce the subsequent grinding operations and the care necessary to be ob served in connection with said operations toa minimum. W

A further object of the present invention is the provision of novel and improved means for accurately uniformly mounting lenses for grinding. r I

Other objects and advantages of the improved construction should be readily apparent by reference to the following specifica- -tion taken in connection with the accompanying drawings, and it will be understood that modifications in the specific details of 1 construction shown and described may be made' Within the scope of the appended claiins without departing from or exceeding the spirit of the invention.

Figure I is a front view of a machine embodying the improvements thereof. 7 I

Figure II is a side elevation thereof? -Figure III is a horizontal sectional view taken as on the line III-III of Figure II. Figure IV is a sectional View on the line IV-IV of Figure III.

Figure V is a detail view illustrating the use of the improved gauge.

Figure. VI is a detail view in elevation of the upper part of the machine showing the side thereof opposite to the side shown in Figure II.

In the drawings, in which there is illustrated a simply constructed form of the in- I ven'tion, the numeral 1 designates the base of the machine and rising therefrom is a standard'Q, upon which is pivoted the collar 3, which is provided with the'bracket arms 4 and 5. The standard 2 is further continned upward and forward terminating in the guide bearing 6, in which is slidably mounted'the plunger rod 7 whose movement is controlled as through the handle 8 which serves to reciprocate the plunger 7 through any suitable and well known form of rack and pinion or like mechanism. The plunger 7 is provided at its upper end with a longitudinally adjustable clamp collar 9, which in turn for finer adjustments bears the adjustable set screw 10, the parts 9 and 10 together forming a flange stop to limit the downward movement of the plungeryas desired.

At its lower end the plunger 7 preferably bears the carrier head 11 having the depending annular flange 12. surrounded by the resilient ring or gasket 13. while it may also be provided centrally with the presscr flange 14: secured as to the spring 15, allowing the yielding of the member 1 1 to accommodate itself to various curves. It is to be noted that the lower portion of the head 11 has been shownas hollowed out, as at 16, andconnected through suitable hoseconnections 17 with the valve 18, the hollowed-out portion 16 extending downwardly within the flange 12 of the tool head so that the air may be exhausted from said space through the connection 17.

It is the purpose of this head and the vacuum created therein to automatically grasp and hold a lens blank during certain steps in the operation of blocking the lens and insure of proper positioning of the lens.

.-'-I.o' cooperate with the member 11 in positioning a lens there IS employed a bracket arm 5 whose construction Wlll be best understood by reference to Figures III and IV,

however. remaining the same.

upper face, since at this point the lens edge is ordinarily more accurately shaped or formed. than at the lower portion of the edge. The radial adjustment referredto permits of adapting this positioning table to different diameters of lens blanks, the apparatus shown, it will be understood, being illustrated for use in connection with circular lens blanks, but it can be suitably modified as to contacts, supports and the like, when other shapes of lens blanks are to be accommodated, the principles of operation,

It will be noted that the collar 3 is pro vided with a second arm to which is secured the operating handle 22v for swinging" the collar and attached parts about the standard 2, this second arm bearing the vertically adjustable stud 23 secured in adjusted position as by the nuts 2% and having its upper end formed with a cone taper por-' tion .25 to fit the corresponding socket 26 in the lens block 2?, the formation of the cone 25 corresponding to that of the spindle on which the lens block is adapted to be subsequentlv placed for grinding of the lens '28.

In the ope 'ation of the improved device the lens 28 preferably suitably" warmed, is placed upon the support 19 with its edge in contact. with the positioning members 20 -which are so-adpisted as to exactly centrally lock the blank upon the support 19,the support 19 at the time of positioning. the lensor immediately thereafter being swung about the column 2 a pivot to bring the center of the support 19 in exact alinement' with the plunger 7. .Vith the lens in this position the handle 8 is actuated either manually or by a foot treadle to depress theplunger and bring the flanges 12 and lei of. the head 11 into engagement with the upper face-of the lens. As the parts are brought into this position the valve 18 is actuated to exhaust the air from the space" enclosed by the flangelf) and on account of theseal created by the gasket 13 around the flange 12' sullicient vacuum will be produced tosecurely hold the lens 28 in position on the tool 11, the plunger being then reversely shifted to lift the lens off the support 19. This operation having been performed the collar 3 is rotated or swung around to bring the stud 23 in alinement with the plunger 7, suitable stops 29 engaging the adjustable. contacts 30 on the collar to limit the swinging movement about the standards so that the two members 19 and 23 may be successively broughtinto correct position. The member 23 bears on it. as it is swung around, the lens block 27, which has preferably been itself heated as by the burners 30 and has had dropped thereon from the pitch dropper 31, a suitable quantity of the pitch or retaining adhesive for blocking the lens. This blocker is preferably so disposedthat when the block 27 is placed in position on the stud and the stud swung to the limit of'itslat'eral movement the side of the block will strike the trip of the dropper and cause exactly the .required amount of pitch to be deposited in plunger being held down until the partshavo had an opportunity to satisfactorily unite. To aid in this uniting, if desired. a fluid supply 3% having a dischargeinozzle portion'35' disposed immediately beneath the conductor 17, may be coupled with the valve 1 8,- which has certain ports controlling the supplyand exhaust of air from the space enclosed by the plunger 12, and other ports allowin'ga small supply of cooling fluid to'flow from thenozzle 35 onto the lens in a line spray to slightly chill the parts so that the glass and pitch will be quickly cooled to adhere together;

'- The parts having been thusunited the plunger is reversely shifted, the vacuum be-:

ingcut out to release the lens which will-then remain held on the block 27. i i i a 1-' The foregoing is a brief description of the general operation of the machine; Attcn= tion' is called to certain specific features inconnection therewitln. which it is lJQ-llQVQdcan behest appreciated and understood at this point. The first feature to which atten tion is-directed is the operation of the stops 9 and 10, clearly illustrated in Figure II:

act position of the upper siirf'aceof the glass with respect to tlieren'iaining parts of the lens grinding machine when the lens is being ground UQhisis of particular importance.

since it enables the grinding machine to be set in exact desired position for the-par ticular work to be PQI'fOl'lliGfl', the parts of the grindingmachine itself and the toolibe-q ing standardized and constant and LheTo'ii'ly' variable factor requiring consideration being that of the glass blank itself, since the. glass blanks may vary in thickness, tllQiblOCkS on which the blanks are mounted may also vary,

and the height sit-which the socket. fits the grinding machine spindle may alsovary due to wear of the several partsso that thisis a-eontin'iial. varyingfaetor in the case of lenses blocked in the ordinary way;

In the case of lenses blocked accordingt'o the'present improvement,however, the cone: corresponds to the cone of. the grinding. machineand the plunger stop 10 is so ad justedthat the lower edgeof; the' flange 12 automatic control for the valve 18, the essenwill come to rest at a certain definite relation to the cone representing the grinding machine. When the lens block is mounted on the cone,therefore, it occupies the same relationship to the plunger that it will to the spindle of the grinding machine, while as the flange presses down onthe upper surface of the glass or surface to be operated upon and brings this surface down a certain prescribed amount, or in, other words, to a certain prescribed relation to the tapered cone of the spindle, the glass surface will be in the identical relation when the block is transferred to the grinding machine, the variables of thickness of pitch, fit of block, thickness of glass blank, and the like, all being taken care of through the amount of pitch which is squeezed out from between theblock and blank automatically by the machine. The result is that much less skill on the part of the operator carrying on the grinding operation, less constant attention to the work and standardization of the work is rendered possible for the first time through the use ofthis improved process ofblocking which may becarried out as by themachine forming the subject matter of the present application. I

A further feature of this. improved machine to which attention is directed is the tial being that the valve shall be automatically operated to create the necessary retaining vacuum when the plungeris first brought toward the glass blank on the support 19, that this vacuum will be main taincd while the plunger is raised with the blank and while the plunger is brought down to press the blank against the block butthe vacuum cutoff before the plunger is raised so the glass blank will not be pulled loose from the block at the completion of the blocking operation. This. may, of course, be accomplished by'a variety of specific :mechanism, and what is to be claimed and protected, therefore, is a'mec-hanism for automatically accomplishing the desired re- Sult' irrespective of the specific details.

In 'the form of invention illustrated there is shown the va-lve'18 as provided with the operating'handle 36 adapted to be depressed by the pin 37 on the plunger plate 38 which is preferably carried by the adjustable collar 9, since the main point that is desired is that the valve operate in certain relation to the movement of'the plunger irrespective of the adjustment of the plunger through the stop. This plate 38 is provided with the transversely extending slot 39 and the trans- .-verse slide 40 having the lifting pin 41 projecting forwardly therefrom for engagement with the handle 36 and riding rearwardly in the track or groove 42 formed in the member 6. It will be noted that this groove is of such form that as the plunger plate is raised end: of the valve operating lever 36, while as the plate is depressed the pin will ride downward clear of the lever until almost to the limit of movement of the plate, when it it will move inward beneath the lever and then on its upper movement will engage and shift the lever and thus the valve in reverse direction from what it is shifted by the pin 37. The advantage of this is that in the initial operation of the machine the pin 37 will partially depress the raised valve or, lever handle 36 opening the air exhaust line so the vacuum is-created engaging the lens blank. Then as the plunger and lens blank are raised the pin 37 will move out of engagement with the lever which will stay in the position of the valve open. In block-i ing the lens the pin 37 will move downward and again engage and further depress the lever or handle 36 shutting off the vacuum just as the blank is brought into engagement with the pitch 33 and allowing a slow seepage of air into the vacuum space accordinglyreleasing the grasp on, the blank. At this point the pin-41 is beneath the lever r and as the plunger is reversely shifted the pin will raise the lever 36 temporarily opening and again closing the vacuum line in the upward movement when the parts are in position for the next series of operations. As has been mentioned, the controlling valve 18 is a double valve, as illustrated, having a portion controlling the air exhaust and a portion the supply of cooling fluid.

In Figure V, there is illustrated an improved gauge for use in setting the machine, said gauge being substantially in the similitude of a lens block having a tapered socket 43 adapted to be selectively engaged on the cone 25 or on a similar cone of a grinding machine, said gauge having an upstanding portion 44 corresponding in height to the combined thickness ofthe ordinary block 27, pitch 33 and lens 28 so that when the gauge is placed in position on the stud 25 the flange 12 of the presser head 11 may be brought down to bear against the gauge and the stop 10 then set so that the flange, justbealjsv against the portion 44, r

The gauge may then be removed and simi larly employed on the grinding machine to which the blocked lenses are transferred and correspond t iereto.

From the foregoing specification taken in connection with the accompanying drawngs, the construction and operation of the be subsequently ground.

improved: machine for use iir the accurate blocking of ophthalmic lens blanks or the like should be readily understood, and it Will'- be seen that there has been provided a sim- -ple and eilicient machine for the intended \Vhat I claim is: i 1. In a machine'of the character described, the combination with a plunger, of means. for temporarily securing a lens blank onthepl'unger, means for automatically releasing said temporary securing means to permit the release of the blank, means for supporting lens block in alinement Withthe plunger,- and means for limiting the movement of the plunger and lens in the direction of the block.

2. A machine of the character described including a standard, a swingingr member on the standard having a pair of arms. a" lens positioning device carried by one ofthe' arms, and a lens block receivingdevi ce car-- ried by the other of the arms; a plunger, the said arms being adaptedtobe selectively swung. into operative relation to the plunger, and means on the plunger for grasping ablank on the l'enssupporting. arm anctfor shitting the grasped blankto definite position. with respect to the block receiving arm.

A lens blocking machine comprising a plunger. a lens holder, a lens block holder," means for successively presenting the lens holder, and lens block holder in operative relation to the plunger, means on the plung or for automatically grasping a lens blank when presented by its holder and for automatically releasing the blank.

-.l-. A lens blocking machine comprising a plunger, :1 lens holder, :1 lens block h'oldei", means for successively presenting the lens holder, and lens block holder inoperative relation to the plunger, means on the plunger for automatically grasping a lensblank'u'hen presented by the holder and for automatically releasing the blank, and means tor'automatically supplying adhesive to the lens block before it is brought into o icrativc"relation to the plunger. 1 I I,

A machine of the character described, including a base, a plunger supported by the base and a table rotatable-on the base, said i member h aving a lens blank supportingportion and a lens block receiving portion adapted to be selectively presented in predetermined position with respect'tothe plun'g er through rotation of the table. 6. A machine of the character described, including a base and a niember'rotatable on the base, said member having a. lens blank positioning. portion and a' lens' block receiv ing' portion adapted to be selectively presentedin operative position: through rota tion of the member, and a plungercarried by the base for cooperation with the said:

, parts when they are in operative position,

said plunger having means for grasping a blank-from the holder and su'pportthe blan'k vice and a: lens block holder adapted to be selectively brought into operative relation tot-he plunger, means forj temporarily retaining a. lens blank on the plunger, and stops for limiting the oscillation of=the" bracket to autoni'at'icall y' position the parts in proper relation.

8. A machine of the character described including a plunger] and an' oscillat'able bracket, having a lens blank po'sitioningj (le vice and-a lens block holder adapted to be selectively brought into-operative relation to the plunger, means for temporarily re taining a lens blank on the plunger, means for automatically releasing 'sa'id temporary.

retaining-means t opermit the release of the blank, and adjustable stops for limiting'thef oscillation of the bracket to automatically" position the parts in proper relation.

'9. A machine of the character described including a plunger and an oscillatable movement of the plunger in the direction of the oscillatable.bracket.

10. machine of the character described including a plunger and an osoillatable.

bracket having a lens blank positioning device and a lens blockho'ldei' adapted to be' selectively brought into operativejrelation to the plunger, means for temporarily retaining. a lens blank on the plunger, means tor automatically releasing said temporary retaining means to permit the'relea'se oft-he blank, adjustable stops for limiting the oscillation of" the bracket to automatically position the parts in proper relation, and

adjustable means for limiting the movement of the plungerin the direction of the oscillatable bracket;

11. A-devi'ee of the character described, including a plunger having a suction head" and an o'seillat'able bracket having a avork" positioning portion and a \vOrICrcCeiving portion adapted to be selectively placed in aliiie'inen't with the" plunger, means for reciprocating the plunger'i-n the direction of the bracket, whereby the suctionhead on' the plunger may" grasp the work'from' the positioning device and transfer it to the work receiving device.

12. In a device of the character described, the combination with a stud shaped to simulate a lens grinding machine spindle,

including a portion designed to receive a lens block, of means including a plunger for pressing a lens in the direction of the stud,

,means for temporarily retaining a lens blank on the plunger, means for automatically releasing said temporary retaining means to permit the release of the blank and means for limiting the pressure in the direction of the stud to a predetermined distance from the spindle.-

13. A suction head for a lens blocker having 'a projecting annulus to fit the curve of the lens and press the lens on its block, and a gasket surrounding the annulus to seal the joint between the lens and an- I V of the lens and press the lens on its block, a gasket surrounding the annulus to seal the joint between the lens and annulus, means for exhausting the air from the space enclosed by the gasket, and a central presser carried by the head for engagement with the" center of the lens blank.

16. A machine for the purpose described, including a base, a bracket oscillatable 011 the base having a lens supporting portion and a lens block supporting portion, means for positioning a lens on the lens supporting portion, and means for transferring a positioned lens from said supporting portion to predetermined relation to the lens block suport. p 17 A device of the character described including a base, a bracket oscillatable on the base and having av lens block support and a lens support, a plunger on the base for selective cooperation with the block support or lens support, means for temporarily retaining a lens blank on the plunger and a heater carried by the base and disposed in position to cooperate With the block support when the lens support is in alinement with the plunger.

18. A device of the character described including a base, a bracket oscillatable on the base and having a lens block support and a lens support, a plunger on the base for selective cooperation with the block support -or lens support, means for temporarily retainlng a lens blank on the plunger, a heater carried by the base and disposed in position to cooperate with the block support when the lens support is in alinement with the plunger, and an adhesive discharge device disposed adjacent the heater.

"19. In a machine as set forth, a frame, a plunger mounted thereon, an oscillatory bracket having a lens blank positioning de vice and a lens block holder to be selectively brought into operative relation to the plunger, and means for temporarily retaining a lens blank on the plunger.

20. In a machine as set forth, a frame, a

plunger mounted thereon, an oscillatory bracket having a lens blank positioning device and a lens block holder to be selectively brought into operative relation to the plunger, means for temporarily retaining a lens blank on the plunger, and means for automatically releasing said temporary retaining means to permit the release of the blank.

21. In a machine as set forth, the combination with a plunger, of means for temporarily securing the lens blank on the plun ger, means for automatically releasing said temporary retaining means, and means for supporting a lens block in alignment with the plunger.

In testimony whereof I have affixed. my signature, in presence of two witnesses.

GILBERT S. DEY. lVitnesses:

H. K. PARSONS, ALICE G. HAsKnLL.

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