US1180395A

US1180395A - Process for forming bifocal lenses.

Info

Publication number: US1180395A
Application number: US86968014A
Authority: US
Inventors: Harry William Hill
Original assignee: American Optical Corp
Current assignee: American Optical Corp
Priority date: 1914-10-31
Filing date: 1914-10-31
Publication date: 1916-04-25
Anticipated expiration: 1933-04-25

Description

H. w. HILL. V

PROCESS FOR FORMING BIFOCAL LENSES. APPLcATN FILED oc'T. 31.1914.

A '1,180,39 5. Patented Apr. 25,1916.

I/VVE/VTOR HARRY W HILL #MAWMW A TTORNEYS bein wasted. as is 'the 'HARRY WILLIAM HILL. (ssoU'rHBRIDGE, MAssAcHUsE-'r'rs ASSIGNOR TO AMERICAN OPTICAL COMPANY. OF SOUTHBR-IDGE. MASSACHUSETTS A VOLUNTARY ASSOCIA- TION OF MASSACHUSETTS.

PROCESS FOR FOR-MING BIFOCAL LENSES.

Specification of Letters Patent..

Patented Apr. 25, 1916.

Application filed October 31, *1914 Serial No; 869580. 4 i

To ai?. Ic 710112 it may eonccrn Be it known that I. I-IARRY`V. HILL`, a citizen ot the Ynited States residng at Southbridfe. in the County of -lvorcester and State of Massachusetts. have invented certain new and useful. Improvements in l''ocesses for Forming Bifocal -Lenses` of which the following 'a s pecification.

This invention-relatesto improvements in* bitocal 'lenses. and haspartiular"'=reference to those orms of bifbcal lense's which consist of two pieces of lass of dissmilar index seem-ed to each other as by fusion.

The leading: object of the'invention is the prorision ot. an improved process for, secpriu the most satist'actory uniting of the 'two parts ot'n bifocah and to rednce to a minimum au detect in the lens on account ot' said 'usion.

.i. t'urther object of the invention is the provision of an improved process which will permit of unitin r the najorportion of the blank and segment without the interposition of any foreign 'matter between the unit- 'ing faces of the blank and segment as has hitherto been deemed necessary.

Another objectofthis intention is the provision of an improved process of' nniting the main and segmentportions of an ophthahuic bitocallens blank in such manner that the entire blank may be used in the formation ot' the finished lens in place of a part case with the processes at present employed.

Other obieets and advantages of this improved process ot' formin; bifocal lenses should be readily apparent by reference to the following description taken -in conneotion with the aceommirringdrawinf's. and it will be understoea that any modifieations may bemade pended claims without exceedin' the spirit' of this inventon.

Figur-e I represeuts a plan View with the parts in position t'or tusion. Fig. II represents a similar riew at'ter fusion. Fig. III represents a sectional View onthe line lII--IIl ot' Fri. I. Vip'. IV represents a similar View on the-line 'IV- IV of Fig. I. Fig. V representa seetional View on the 'line Y-V of Fig. ll. Fi VI represents a View similar jo Fig. IVbut illustratin: a modified Construction.

In the. drawings, in

within the seope of the apdepartinf from or' which simila-:char-- acters' of reference are emploj'ed to denote correspondmg pa rts throughout thesereral views, the numeral l designates an opht-halmic lens blank having sutably formed there in the eountersink "2 adapted to receive the segment 3. said segment being forme'd from glass of a different index from that ofthe'. blank l. i

In that embodiment of the process-herewith illustrated the segment is formed'with the heveled surrounding edge as ati, and when placed n position for fusmg one or more a'ngle peces 5 are dsposedwth one face of the angle resting upon the 'main blank l and the other 'ace of the: angle bear-ing against the bevet-l onthe segment, the angle member .or members I being preferably secu'ed by suitable adhesives to either the main blank l or the segment 3. or to .both. to avoid lability of slippin'g. By ref- Figs. II- and IV. the

erence particularly to useof these members 5 wllbe clearly underst-ood. and `1t will be seen that they` serve to hold a 'portion of the segment'. slightly' s'paced from the face *of the -countersink 2, the other end of the segmentrestmg againstturbing the relation of the main blank and -either of;

segment andwithout injury to said parts.

In Fg.

member 3 has for-med thereon the projection 'or rib t' adaptedto be enaged by the wedge'- like members i' 'for holding the disk at the ed es and keeping itspaced fromthe main portion 1 ot' the blank.- The wedge-like for mation of the members? permits oftheir adjustiuent to retain-the segment-- in desired. relation to themain blank` whileheating sotteniug of the thin nember G wllreadily allow the'segnent'to sin-k into'cotrect position andengagement with the counter-sint( slifht softening VI is illusti'ated a su ht modij-" -fied form of nn" device in which the segmt t' 'SO the edge of the cmntersink` if desirechasf "45 portion, 'forming segment with a beveled o beat, wherehy the bevelecl edge s'sutficiently by proprocesses.

'15 Ic'laim:

1; The-.p"`:ess of fo-nng afbifo caflens blank r consistng in forming. one ofthe two partsto be united with "a slg'htl y shege-led edge, ""suppo rtng 7 the' two prts .be ;spaced' 'ela tion by independent. engagnggcl beveled eclge, and` the pa'ts .fto a temperature snffi ;se -sef the bevelel member that sli-l' etlownward' on the pport into edgesupportmg'sad parts n spaped rela:

ton'by angle members engagng the upp'.. faceof the main blank and the beveled ,edge .oflthegsegmenm and subjeeting the payts to' heat, Whereby the beveled edge 'is suffieiently oftened to ermit the segment to slide g doy nwa rd on the angle members nto .en -"gagementw1th the mam blank, and sub ect: nthe pa'rts 'to a contnuing heat-s uficent to fuse `the mein'hlank and segment 'into a unitary strueture. v 3-. The p ocess of formng a bifocal lens` blank; conssting in employng a ninp or- 'ton, forming a countersink in' said main edge, supporting sa cl' p'arts' in spa-ced relation by angle members engang 'the upper face of themz n' hlank ancl the beveled edge 'of-the segment, and subjeeting the parte' to softened to permit the segment to slcle doWnWa-;cl on the anglemembers into en: 'g'agement With the man hlanlg eontnung the heat sutficientlyto fuse the mein blank 5.3 and seg'ment into a unit -r g structure and removing the angle members from the ex posed faces ot the main and segment por tons of the blank, prioto the g'irding ot' the testltznt product into a finished lens.

4:. The process of formule' ,21 bfocal lens blank, consstng in" fol-mine; main blank with a `counte'sink theren, formng a segment blank with a. convex curvatu'e ap-` a -oximntely the 'same as thatof the countersnk, and -Wth a' fia ng betelecl 'eclgeacl alar pacng members on. the .main blank, movng sad members n'to engagement wth thearng bevel ,of thesegnent to support the segment spaeed fi-'om the' main 'blank suhjeeting the partshw a` eldn'g tempe-a 'mre whet-eby thebeyelecl edge. is softened' to lloiv the segment to move -clew warcl` into eng'age'ment with the main blank,- and' 'continuitgsad temperature* to fnse the parts together.

5. The-process 'of untng blnks for 21 seem-ing: the spcng membersn position,

suppoi ts to -one ;of the, pa-ts. plcn'g the other part between the uppe` po'tions (f-thi* supports, -wherebv thei-,wo parts 'are held in space& relatiom' and subjeetin-g the parts' to; a weldng "temperature whereby ;one 2 of' the partis caused 'to 'Softn and s "t tle dow n uponend' adhe'e to the other.

The process', of formi-ng; a bfocal lens, coisist'g in polishing thetwo surfaces to be' unit d, sipnortng .the par'ts in r-spaeecl relation. by snppo1 ts engagng the side only of one of the pa'ts, ndrsubjectg the parte to 'a 'fsing temneratti'e whereby the sides are softened to allow the parts to move into engagement with-eachother and-unte Without benjding of the polished stu-faces the'eof.

vetm-e on the other 'pat-t, supporting the pats in spacecl relaton by meansengaging the later-al egeonly of the conyex part, end -subjectng the' parts to .a fusmg temperature',- Whereby the edge* of the convex member s caused'to softenand pernnt the mem ton thereof.

in presence of two witnesses( j HARRY'WVILLIAM HILLQ 'XVtnesses: f

- 'H: K.-PARs`oNs, v EDI'IH M. HALVORSEN.

7. Thept'ocess of formng ebfoeal lens, consstng .in grindng endi polishing ai' counterinkl i-one of the parte fot-ming and polshng a cor'eponng com-'ex curher tosettledoyvn-uponf and adhe e. to the-'x I other Without bend lng of thepolished por;