US2520977A - Vacuum lens block - Google Patents

Description

Patented Sept. 5, 1950 VACUUM` LENS BLOCK' Mcrteni Suben, NewYork, Ni/ass'gnarzt'oi Ivens--y Block' Gorporationg, New York,v N1.. Ya, a; corpora.-v

tion of'NeW- York Application May' 8', 1947, Serial- No'. 746,789"

G'Glam (Cl. 51-2315):

This' invention relates to what` are generally termed blocks for' use in supporting lenses' during' the operation of grinding the same. More par'- ticularly, my invention deals With a lens block adapted for' mounting primarily' upon concaved' surfaces of'lenses or workpiecesin supportfcf' the' lens or workpiece in the operation of' grinding or' polishing the opposed o1' convexed surface there-- of. Still more particularly', the invention deals withy a method of blocking whereinv a suction cup'l and pressure ring are employed in firm support of the cupfupon the lens, and further', in provid-- ing a block device having a deep seated conel for' maintaining the lens guiding or' manipulating pin ask close to the concavedI surfacev of the lens as possible. The novelv features of' the invention` will be` best understood`r from the following'. descripti'on when taken together with the accom-v panying drawing in which` certain embodiments of: the' invention are disclosed', and'. in which the separate parts are designated by suitable referience characters in each of the views, and. in which:

Fig. 1' is a diagrammatic view illustrating' the` use of one of my improved blocking devices, parts' of' the construction being shown in section, and' parts in elevation.

Fig'. 2 is a sectional view through one of my' improved devices, prior to attaching the' same' to', a. lens, and indicating in dotted lines the rst' operation in establishing the attachment;- and'` Fig'. 3` is an enlargedv View similar to Fig'. 2', showing. the device attached' to the lens'.

The device and method' hereinf disclosed', constitutes a continuation of the'structure disclosed;

i'n myv prior application Serial Number 716.3351, i'led: December 14, 1946.

As set forth in said earlier application, in the grinding' and polishing of lenses', it has' been' cus-- tomaryA to employ blocking toolsiwhich have beenadhered to the lens by the use of a heated pitchor similar agent, which agent has been' chilled in' establishing secure attachment' of. the tool tov the lens.. In this procedure, it has' been diflicult to center the lens on the blockingI tool, and iur` thermore, the procedure has been expensive froml the standpoint ofthe skill of operators mounting'lens on blocks, and still further', costly in the necessity of having to remove the` pitch or other agent from the lens and the necessity'of cleaning the blocks in further use thereof. Further, my' improved method eliminatesall danger of scratch-A ing4 or marring' the lenses, which'v liasA been exrperienced by the known. processes'.

In Fig. 1 of the drawing, I havediagrammatil 2, cally'ifllustrated one adaptation and.' use of my'in. vention, andi in' this iigure, 5. represents a. tank, in which.. the grinding or' polishing: compound; is arranged and indicated at 6'. Supported in?. a suitablev bearing 1'? at the' bottom of the tankis' a, shaft 8i rotated' by asuitable driving source. through a belt or other drive, as at` 9; Supported` upon' the: upper' end-1 of the shaft 81 is a grinding tooll having' a concaved. surface lili for grindi'ng the outer' convex' surface of a lens or other' workpiece lf2; Pivoted to one: side of the tank'. 5', as'. seen at I3=, is a lever lli' actuated by handi in'- carryingcentrally` above the tank'. a freely swing-'-` ing' center' pin,` I5` having a conical' lower end'v i6.

pin? adapted to engage` the block generally identi-lied, as'. tlf, in. manipulating. the. block to2 move the lens over the: surface'. H' of the' grinding on polishing' tool'. It?, as the' latter isbeing rotated' at high, speed'.

Theblocking; device or tool* I1,.in. the constructionshown'-, comprises six'. parts, namely' a' suction cup:l F83 Within which is anchored a sleeve. {9,a stud 201 ai pressure ring: orcollar 25|, a' tightening or' pressure nut1221,.anda pointer plug 23, thelatter' being iorcefnlly'h'eld in' the stud 2(11' and beingv preferably.' formed of' hardened material and? is provided. with a. conical seat 254'. adapted' to re'-A ceive the conical; end In' of the: pin l5. The stud has'I a, conica-l. bore'- 2 5 registering. with. the sea'tl` 2a?, as' clearly seen, sov that' the' conical end: llt

mi thet pini |55', is tree to pa-ss into andv out of4` the seat 24'..

The cup- I'8' is preferably' formed of" ay rubber oii highi resilient: properties as' weil as' tough char'- anteristics, so: as to withstand the stressesv and strains to which the cup is subjected. The cup` has a: substantially' straight outer' conical' surface 2E', joining a slightly' curved inner surface 21: iny a pointed;peripheral4 edge 28. The surfaces 26' and 21' are' contracted slightly in. the' direction cir the: peripheral edge' as clearly seen in. Figi; 2' of' the;l drawing,v and the rounded concaved inner surface.- 2"!! joins' a. flat centerf surface 29f. The` flattening:l of the' surface. 2SA enables. thesle'eve'. till to be maintained in close proXimidv-yI to theisurface 219', leaving: arelatively thin Wall 3Q?. The sleeve Hl'isiinternally'threaded, as seen at 31, toireceive' the reduced externally threadedportion 32 of the' stud.. The outer or peripheral surface of the sleeve iszknurl'ed", as. seen at 33, in.v Fig. 2., to' es'- tab'lish anchorage of the sleeve in the' cup retainingthesame against'rotary, as well as axial movement.v The. outer end-i of thesleeve, t9: termin'a'tes; flush withv the upper flat surface,l 3542; of the; cup.` The stud 2! nasi a larga diameter:l ex.-

ternal thread 35 adapted to be engaged by thenut 22. The ring or collar comprises ahorizontal wall portion 36 with anaperture 31 therein to freely pass over the enlarged threadedend 35 of thestud 20 and a depending annular wall portion adapted to cooperate With thesurface 26 of the cup, as later described.

In the use of my improved blocking tool, the cup I8 of the tool is rst centered approximately upon the lens I2, using as a guide, the center marking 39, shown in Figs. 2 and 8, with the several parts of the tool partially assembled, as indicated in Fig. 2, whereupon the tool is pressed in the direction of the concaved surface I2' of the lens I'2 which brings the cup I3 substantially into the position shown in dotted lines in Fig. 2, with thesurface 29 closely adjacent the central portion of the surface I2. When in this position, the final adjustment and centering of the cup I8 upon the lens is performed, after which thescrew 22 is now tightened so as to force the pressure ring or collar 2| or the dependingportion 38 thereof downwardly upon thesurface 26 of the cup, while at the same time, drawing the center portion of the cup upwardly, the result of which is indicated at least diagrammatically inV Fig. 3 of the drawing.

Upon completing this operating, bringing the parts to a position substantially similar to that shown in Fig. 3, the outer portion of the cup I8 will have established at least two annular pressu're contacts upon the convex surface I2 of the lens I2, one 4in a relatively narrow annular band, represented by the light lines, as indicated at 40 in Fig. 3, and the other by a wider annular band, as at 4I in said figure, the latter band establishing the rmest engagement of the cup I8 with the lens. Whereas, the band 4Q is sufciently tightto form a seal preventing uid or grinding'compound ormaterial entering between the cup and the surface of the lens. In this connection, it may be said that the band y:il comprises the primary band and theband 40, the secondary band.

In the above operation of securing the cup to the lens, theinner surface 21 takes a convex curvature, as indicated at 21', Fig, 3, closely adjacent and inwardly of the band 4 I On the other hand, thewall 30 including thesurface 29 thereof is convexed downwardly, the latter being the result of the vacuum or suction in thechamber 42.

InFig. 3, the relative positions of the parts are exaggerated from a standpoint of clarity. In some instances, the degree of movement of the parts relative to each other will be' materially varied, depending here also upon the curvature of the lens.

Keeping in mind that thewall portion 38 of the' ring or collar 2| is engaging theconical surface 26, the pressure engagement with the collar is such as to establish the excessive pressure engagement of the cup with the lens in the band 4I at a position substantially as indicated in Fig. 3, or in other words, at a point inwardly with respect t the engagement of thewall 38 with the cup, as indicated at 43.

The blocking tool assembled with the lens, as indicated above, may now be placed in the apparatus, and upon grinding or polishing, the tool I 0 and the -pin I5 are `moved into engagement with the tool to manipulate the lens in the manner stated above. After the lens or other workpiece I2 has been ground or polished, the blocking tool or device is removed from the lens by'simply loosening thenut 22 to relieve the pressure of the collar upon the cone I8, after whichthe periphery of the cone may be flexed away from the lens allowing air to enter thechamber 42, which will quickly free the device from the lens.

My improved device may be used in conjunction with lenses of any type and kind, and regardless of the contour of the surface engaged by the tool. The tool, however, is particularly adaptable for use in mounting upon concaved surfaces, but will establish a rm engagement with fiat or other surfaces.

It will be apparent that theplug 23 is tapered, to facilitate removal 0f the plug for replacement when the same becomes worn. The same can be readily driven from the stud ormember 26 when the latter is detached from the cup or the sleeve I9 thereof. It will also be apparent that theconical bore 25 is made with a wide throat to facilitate movement of the pin I5 therein in manipulating the block in the operation of grinding or polishing the lens.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent is:

l. A device of the character described comprising a suction cup, an internally threaded sleeve embedded axially in the cup and exposed through one end thereof, said cup being substantiallyl conical in form, the walls of the cup contracting to the outer peripheral portion thereof, the other surface of th-e cup within the cone being flat centrally and axially thereof, a member in threadedengagement with the sleeve, a Ipressure Yring mounted on said member, said ring having a horizontal wall and an annular wall depending at right angles to said horizontal wall, said annular wall engaging the walls of the cup in applying pressure thereto, and a nut adjustable on said threaded member in applying pressure to said ring while simultaneously drawing the central portion of the cup in a direction opposite to the applied -pressure to said cup by said ring.

2. A suction cup device of the character described comprising a substantially conical cupv body of yieldable material, a threaded member anchored to the axial portion of said body, a ring for applying pressure to the outer surface of said body between the axial and peripheral portions thereof, means coupled with the threaded member engaging the ring to move the same into engagement with said body to establish two circumferential pressure area engagements of the inner surface of said body with a supporting surface, one pressure area being adjacent the ring and the other at the periphery of the cup body, said threaded member comprising a part anchored in said body and a stud detachable with respect to said part, and said stud having a conical recess.

3. A suction cup ldevice of the character described comprising a substantially conical cup body of yieldable material, a threaded member anchored to the axial portion of said body, a ring for applying pressure to the outer surface of said body between the axial .and peripheral portions thereof, means coupled with the threaded member engaging the ring to move the same into engagement with said body to establish two cir.- cumferential pressure area engagements of the inner surface of said body with a supporting surface, one pressure area being adjacent the ring and the other at the periphery of the cup body, said threaded member comprising a part anchored in said body and a stud detachable with respect' to said part, and said stud having a conical recess, and a conical tapered plug detachable with respect tosaid stud. A v

4. In suction cup devices of the character described, a conical cup body of yieldable material, a threaded sleeve anchored in said body, a stud detachable with respect to said sleeve, a tapered plug detachable with respect to said stud, said plug and stud having registering conical recesses, and the conical recess of said stud extending, at its outer end, to a point adjacent the outside diameter cf the stud to provide a Wide entrance throat.

5. In suction cup devices of the character described, a conical cup body of yieldable material, a threaded sleeve anchored in said body, a stud detachable with respect to said sleeve, a tapered plug detachable with respect to said stud, said plug and stud having registering conical recesses, the conical recess of said stud extending, at its outer end, to a point adjacent the outside diameter of the stud to provide a Wide entrance throat,

inner ends of the stud and plug terminating 20 6. In suction cups of the character described, a conical cup body of yieldable material, means centrally of said body and exposed through the outer surface thereof for attaching the body to a supporting surface, said means comprising a device embedded and anchored in the central portion of the cup body, said device having means forming a deep conical recess opening outwardly through said device, a pressure ring for engaging the cup body, and means adjustable on said device for urging said ring in engagement with said cup body.

MORTEN SUBEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 998,718 Schultze July 25, 1911 1,871,113 Compter et al. Aug. 9, 1932

Images