US2248955A - Sapphire grinding means - Google Patents

Sapphire grinding means Download PDF

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US2248955A
US2248955A US250668A US25066839A US2248955A US 2248955 A US2248955 A US 2248955A US 250668 A US250668 A US 250668A US 25066839 A US25066839 A US 25066839A US 2248955 A US2248955 A US 2248955A
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sapphire
wheel
groove
roller
grinding
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US250668A
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Frank L Capps
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Frank L Capps
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B19/00Single-purpose machines or devices for particular grinding operations not covered by any other main group
    • B24B19/16Single-purpose machines or devices for particular grinding operations not covered by any other main group for grinding sharp-pointed workpieces, e.g. needles, pens, fish hooks, tweezers or record player styli
    • B24B19/165Phonograph needles and the like

Description

3 Sheets-Sheet l F. L. CAPPS SAPPHIRE GRINDING MEANS Filed Jan. 13, 1959 July 15, 1941.
INVENTOR I FRANK I... CAPPS.
ATTORNEY FIG. 2.
July 15, 1941-. L. CAPPS I v I 3 SAPPHIRE GRINDING MEANS Filed Jan. 13, 1939 3 Sheets-Sheet 2 4O\ f W INVENTOR FIG. 4
FRANK 1.. CAPPS. BY I I ATTORNEY July 15, 1941. c p 'g SAPPHIR GRINDING MEANS Filed Jan. 13, 1939 3 Sheets-Sheet 3 FIG. 5
. INVENTOR. FRANK l... CAPPS.
Patented July 15, 1941 ha-UNITED S E A T OFF-ICE sArPHmE GRINDING MEANS Frank L. .Capps, New York, N. Y. Application January 13, 1939, Serial No. 250,668
. aim- This invention relates to new and useful improvements in the art of sound recording and has particular relation to' a means and method of automatically grinding into cylindrical shapes sapphires which are polygonal" in transverse section ancl which are to bemad-einto sound recording Styli.
The objects and advantages of the invention will become apparent from a consideration of the following detailed description taken in connection' with the accompanying drawings wherein a'satisfactory embodiment of'the invention is shown. However, it is to be understood .that theinvention is not limited to the details disclosed butincludes all such variations and modifi'cations as fall within the spirit of the invention and the scope of'the appended claims.
In the drawingst Fig. 1 is a front elevational'view of a machine madein accordance with the invention; 7 v s Fig. 2 is a side elevational view of said machine; the view being taken lookingfrom' the fi n si I Fig. 3 is atop plan view of themachine;
Fig. 4 is aside elevationalview of the machine, the view being tak en as looking from the left inFigl;
' Figp5 -is'a detail elevational view "showing a -mounting device'employed; I
' j Fig. 6 i'sa view taken at right angles to Fig.'5 and showing the means mounted by the device of Fig. 5;
Fig.7 is an enlarged plan view showing a portion of the grinding wheel and certain parts associated therewith;
Fig. 8 is a detail view onan enlarged scale showing the mounting of a leveremployed;
Fig. 9 is an enlarged front elevational view of a portion of the machine;
Fig. 10 is a detail sectional view taken as along gularly related portions i5 and I6 and also carryinga pair of spacedarms I] and l8. Arms .A pulley 4| on a shaft .42,- mounted in the'bearings l9 and 2D,has trained thereover a belt 43 designated 49 and. shown best in Figs. 5 and 6. The device '49 includes a plate like portion 50 such portions grip -or clamp the member.
through the'slot 2! and equipped with a securing nut 24. Bracket 22 includes vertical arms 25 and 25 at their upperends having split bearing-like portions 21 and 28 secured together as byscrews 29. Portions?! and'28 support a shaftlike member 30 and hold the same against movement when the screws 29 are'tightened to have Obviously the braclretZZ together with its bearinglike portions 21 and 28 is adjustable along the extension I5. i
A bracket-like member 3lis also secured to the extension 15, a bolt 32 passing through the slot-2 l together with a nut 33 on the lower end of said'bolt serving 'to secure the member I in the desired-position on the extension. Meman upper portion of Which'is supported a water or other liquid container 35. The container is secured to the rod by means of a device 36 having one end portion clamped about the rod by a means '31." and having" its other endportion 38 comprisinga-rest for the container.
Mounted. on the base 10 is an electric motor .39 having a pulley, secured to the shaft thereof.
which ,belt is also trained over the pulley 40 whereby, the shaft 42 is driven bythe motor 39.
rod 34 has passing therethrough a threaded stud 48 carryinga, shaft supporting device generally tdwhich the stud 48- is attached and such portioncarries a. pair of parts 5| and 52 into the outer or free ends of which isthreaded a screw 53 adapted when tightened to; draw such parts toward one another. A tube 54 passes between .the parts 5| and 52 and when the screw 53 .is
tightened such tubeis clampingly held. On the member between the plate-like por- .tion-50 and the rod 34'is a part 55 including a plateelike' portion 56 facing the portion ,50. The arrangement is such that on loosening of ailnut 51 onthe stud 48 the device 49' may be rotated with the stud as 'an axis. However, this .driving relation with the worm 6 I.
roller 59 is being driven when ever the grinding is for the purpose of adjustment only and when the parts have been adjusted as will hereinafter appear the nut is tightened and remains in that condition.
Passing through and rotatable in the tube 54 is a shaft 58 carrying a roller 59 of rubber or other frictional material. The roller is secured to the forward end of the shaft 58 and to the rear end of such shaft is secured a worm gear 60 meshing with a worm 6I, theworm and worm gear being enclosed in a casing 62. Since the device 49 may be adjusted on loosening of screw 48 and as the shaft 58 is movable with the de-' N the purpose of such cooperation the roller is rotated in a direction transverse or across-the direction of rotation of the wheel. A bracket mem- .ber 63 extends forwardly from the upright I4 i and carries a pulley 64 and a shaft 65 on which the pulley issecured. Trained over the pulley '64 and the pulley 45 on the shaft 42 is a belt 66 w hereby the shaft 6-5 is driven from the shaft 42. Attached to shaft 65 is, one end of a fiexible shaft 61 the other end of which is connected in Thus the wheel 46 is rotating.
Mounted on the extension l6 of the support I I is a gear box 68 containing a reduction gearing (not shown) including a pair of shafts 69 and I0. Secured to the shaft 69 is a pulley II over which shaft 42 and mounted on the shaft 30, to turn thereabout, is a bracket I4 including a block or arm I5 having a tubular projection I6. (see Fig, 8) concentric with said shaft. An L-shaped lever having portions TI and I8 is mounted'on the pro- .jection I6 but is not secured thereto although having a friction fit thereon. The lever portion I'I mounts a pin I9 carrying a roller 19a cooperating with the cam "I3 whereby the lever is rocked about theshaft 30 at predetermined times as will appear. a
. Lever arm 18 extends longitudinally of the block I5 and has an arcuate slot therein through which extends a set screw. 8I threaded into the block. With this arrangement on loosening of the set screw the lever may be adjusted relative to block I5 and shaft 30 after which the screw'will be tightened. A coil spring 82 secured at its upper end to a pin 83 on the lever arm I1 has its lower end secured to the supporting struc- II and serves to maintain the roller 19a action on any sapphire held in the groove while the wheel is rotating. A sapphire to be ground is arranged in the groove to extend longitudinally thereof as shown by the sapphire 81 in Fig. 7.
A plate 88 including a hardened hook-like portion 89 is secured on the outer end of block I5. In the machine the block I5 extends at the side of the grinding wheel 46 and the relation of the parts is such that the hook-like portion 89 extends overthe groove 86 of the wheel. Therefore when a sapphire is placed in the groove (as by being passed through the bifurcation in the guide means, later to be described), the rotation of the wheel carries the sapphire with the wheel until the lower or forward end of the sapphire engages the extreme end of said portion or stop means 89 after which further movement of the sapphire with the wheel is controlled until the sapphire is released as will appear.
Attention is directed to the fact that the outside wall of the groove 86 is of somewhat less height than the inner wall thereof. The wheel 46 rotates in the direction indicated by the arrow 90 (Figs. 2 and4) while the roller 59 rotates in a clockwise direction as shown by the arrow 9| (Figs. 1. and 3). During grinding of a sapphire the roller 59 is being rotated and is in engagement with the sapphire. Therefore as the wheel 46 carries the sapphire against the stop or limit- 7 ing device 89 the roller 59 is bodily rotating the sapphire and the action of the roller tends to move the sapphire toward the inner wall of the groove. Therefore as the wheel 46 is rotating under the sapphire and the latter is being rotated about its longitudinal axis by the roller 59 it will be clear that the sapphire will be subjected to a grinding action on all its sides and will be ground into a cylindrical shape.
A suitable liquid, as water, to Wash away cut material and prevent clogging of the grinding wheel is supplied to the wheel during a grinding operation. For this purpose a tube 92 is connected with the container 35 to receive liquid therefrom and the tube delivers the liquid to the grinding wheel in the vicinity of the roller 59. The flow of the liquid is controlled by the setting of a valve 93 and preferably the liquid is fed I drop by drop or in a very thin stream. A guide 94 may be mounted as by having a portion 95 thereof secured to the top of the gear box 68 and the guide includes a bifurcated portion 96 arranged over the wheel 46 and with the opening through such portion 96 arranged over the groove of the wheel. With this arrangement sapphires may be fed to the groove 86 through the opening in the guide portion 96.
Bracket I4 includes an extension 91 having a leg-like portion 98 mounted to turn on the outer end portion of the shaft 30. Fixed to theshaft 30 at the inner side of the member 21 is a collar IOI having a pin I02 extending radially therefrom. Adjacent said collar ablock I03 ismounted on said shaft to turn thereabout and such block carries a pin I04 at its outer end and a pin I05 intermediate its ends. A coil spring I06 has its respective ends connected with the pins I02 and I04 and constantly tends to draw said pins toward one "another and'thus to move the block I03 in 'a counterclockwise direction about the shaft 30.
Fixed to the outer end of the block. I03 is an arm I01, the arm being secured tothe block as by screws I08, andsaid arm includes an upstanding portion I09 extending along the side of the block 15 and at its upper end carrying a tubelike part I I0. Part I I is aligned with the groove "86 of the. grinding wheel when the parts are as in Figs. 7 and 9 and the function of such part will later appear.
. "It is noted that the arm III of the bifurcated portion of the guide 94 is somewhat shorter than -the other arm of such portion. This arrange- .ment is provided since if a sapphire fed to the wheel is of unusual diameter or of oddshape it may become embedded in the surface of the roller 59 and be carried out"of the groove-186' by the roller during rotation of the latter. Should this happen the sapphire will not be scraped off the roller by the guide arm I I I but will be again carried intothe groove by the roller-and-berscraped therefrom by the inner wall of the groove and thus returned to the groove for grinding;
Cam I3 includes three finger-like portions ;I I2,'
. U3 and I I4 equally spaced and arranged radially -with respectto the shaft I8 mounting the eam. The body of the cam between the finger-like portions thereof has three'slightly inclined surfaces II5, IIB and I I! inclining respectively from the portion II2 to the portion ,I I3, from the portion II3 to the portion H4 and from the portion II4 to' the portion .I I2." The cam is rotated in the direction indicated by the arrow I I8 in Fig. 2 and obviously the roller ISa is in said figure against the lowest part of the cam surfacerportion II5. With the parts in the indicated positions the stop 89 is partly within the groove 86 in the ,wheel 46 and any sapphire (as the sapphire '8! of Fig. 7') within the groove will have its lower or forward end against the stop 89. Thus as the grinding wheel is rotating in the direction above indicated it will tend to carry the sapphire-with it and to v throw "the sapphire out'of the groove. The stop 89 keeps the sapphire from moving with the wheel and the roller '58 prevents the wheel from throwing the sapphire out of the groove as the wheel revolves. When the roller 19a. an'd'the cam; I 3 are related as shown thestop is in its uppermost position and maintains thesapphire in position under-the upper edge portion of the roller 59 as seen in Fig. 'l w'herein the roller isshown in dotted lines.
{is the grinding operation proceeds, a sapphire having been placed in the groove 86, the-cam I3 is m'oving and as it progresses the roller 19a is gradually raised and the-1evercomprising the arms 11 and I8 is rocked about the shaft 38 movfinger-like cam portions H2, H3 and H4 engages the roller 19a rocking the same sharply outwardly with the result that the lever portions 1! and I8 are rocked in like manner and carry the block I5 and the stop 89 with them permitting the ground sapphire to then move bodily with the wheel 46 and the latter throws the sapphire downwardly and outwardly and the sapphire passes into the tube I I8. Thereafter the sapphire is to be sharpened for use in sound recording or in any other connection as desired.
Thus while the sapphires are fed to the machine one at a time by hand or otherwise, the cam I3 having three fingers the stop 89 is moved from cooperating relation with the wheel or the groove of the wheel three times during each complete revolution of the cam. Obviously the number of finger-like portions on the cam will depend on the speed of rotation of the cam and the relation of such speed to the speed of rotation of the other parts of the machine, 4 I v ;On-lo osen.ing; of nut 51 theroller 59 maybe swung toanout of, the, way position as shown by the dotted lines-in Fig. 2. Arm I8! may move independent of any movement of the bracket I4 when the arm is moved away from the block I5 but the constant tendency of the spring I06 is to keep thearm I01 in positionwith the tube IllI .adiacentthe l late 88. Asthe cam acts to move jthe bracket 14 and the plate 8:8 with stop 89 downwardly the block I5 willengage arm portion 109 andjcause. the tube III] to be, moved down- -wardly against the action of the spring I06. Pin :lll5 carried by. the. block I03 is a stop or limiting .device as when such pin engages the pin I02 on loosening of thezscrews 29 in the bearing-like .members 21 and 28 theshaft 30 and the entire assembly thereon may be adjusted relative to the wheel-4 6 and guide 94. The slotBD in the lever arm Iii provides for adjustment of the lever relative to the block I5 and to the shaft .38 whereby .to have'the cam I3 move the stop 89 in desired relation to the roller 59 whereby to have the sapphire properly.;pr esented to the grinding -,flc .T In the modification shown in Fig. 12 the grinding wheel is designated I28 and'has, a corner portion of its periphery removed providing what is best described as anannularnotch. I.2I to receive thesapphirel'lz to beground. The sapphire will be engaged and rotated by the roller I 23. It isto be understood thatwheel I20 may replace wheel 46 above described and thatroller I23 is the same as the roller 59 previously described. While. notch I2I is not a true groove as is the groove 86 in wheel'AIi yet the purpose is, the samein each instance and the word groovej as used in the following claims is intended; to cover the construction of Fig. 12 as 'well as that of the other figures and such word isnot' to b e read as limiting the claims to a construction embodying a true groove.
Havin'gthus set forth the nature of my invention, what I claim is:
1. In a machine for grinding sapphires for use in the making of soundrecording styli, a grindingwheel, means for rotatingsaid wheel, said wheel having a groove therein of a width greater than the diameter of a sapphire to partly receive the sapphire to be ground, a stop to prevent bodily movement of the sapphire with the wheel, means for bodily rotating the sapphire in said groove in a direction substantially transverse to the direction of rotation of the wheel, a movable support mounting said stop for movement of the latter into and out of stopping relation with the sapphire in the groove, and means for moving said support to carry the stop out of stopping relation with a sapphire in said groove on completion of the grinding of said sapphire.
2. In amachine for grinding sapphires for use in the making of sound recording styli, a grinding wheel, means for rotating said wheel, said wheel having a groove therein to partly receive a sapphire to be ground, a stop to prevent bodily movement of the sapphire with the wheel, means for rotating the sapphire in said groove in a direction transverse to the direction of rotation of said wheel, a movable support mounting said stop for movement of the latter into and out of stopping relation with the sapphire in the groove, and cam means for periodically moving said'support to carry the stop out of stopping relation with the sapphire in said groove.-
3. In a machine for grinding sapphires for use in the making of sound recording styli, a grinding wheel, means for rotating said wheel, said wheel having a groove therein to partly receive a sapphire to be ground, a stop to prevent bodily 1O movement of the sapphire with the wheel,- means for bodily rotating the sapphire in said-groove i'n'a direction transverse to the direction of --rotation of the wheel, a movable support mounting said stop, a spring normally urging said support 15 into position disposing said stop in stoppingrelation with a sapphire in said groove, and means including cam means for moving said support tocarry the stop out of said stopping relation on completion of the grinding of a sapphire. 20
4. In a machine for grinding sapphires for use in the making of sound recording styli, a grinding wheel, means for rotating said wheel, said Wheel having a groove therein to partly receive asapphire to be ground, a stop to prevent bodily .j25 movement of the sapphire with the wheel, means for bodily rotating the sapphirein said groove in 'a direction transverse to the direction of rotation of the wheel, a movable support mounting said stop, a spring normally urging said support into .30 a position disposing said stop in stopping'relation to a sapphire Within said groove, means for moving said support to carry the stop out of said stopping relation on completion of the grinding of the sapphire, and said last meansincluding 5 a cam driven in timed relation to said grinding wheel.
5. In a machine of the character-describedya grinding wheel having a groove to receive a grinding wheel having a groove in its peripherial edge, a guard extending partly over said wheel and including a portion having a slot in alignment with said groove and throughiwhich-sap- -55 phiresmay be fed into the groove, a roller for engaging a sapphire in said groove and rotating such sapphire about its own longitudinal axis, said groove having a high side wall and said guard having anopening in its side portion remote from said wall, and means rotating said -roller in a' direction to carry its sapphire engaging-portion toward said wall whereby should a sapphire become embedded in the roller it will be carried about with the roller and through such opening in the guard and back into the groove to be scraped from the roller by' said high groove 'Wall. I
- 7. In a. machine of the character described, a shaft, a grinding wheel on said shaft, a movable stop associated with said wheel for engagement by a sapphire to be ground and adapted to hold the sapphire against movement with the wheel, a roller mounted for engagement with a sapphire .held by said stop for bodily rotating said sapphire on the wheel, means for rotating said shaft, means for rotating said roller from said shaft, a cam for. periodically moving said stop out of stopping relation with a sapphire on said wheel,
and means driving said cam from said shaft.
8. In a machine of the character described, a shaft,'a grinding wheel on said shaft, a movable stop associated with said wheel for engagement .by a sapphire to be ground and adapted to hold the'sapphireagainst movement with the wheel, a'roller mounted for engagement with a sapphire held bysaid stop for bodily rotating such sapphire on the wheel, means for rotating said shaft, means for rotating said roller from said shaft, a cam for periodically moving said stop out of stopping relation with a sapphire on said wheel, a spring for moving said stop back to position on release by said cam, means driving said cam from said shaft, and a speed reduction gearing in said last drive means.
9. In a machine of the character described, a grinding wheel having a groove to receive a sapphire to be ground, a stop means for limiting movement of a sapphire with the wheel and holding such sapphire in grinding position in said groove, a roller for engaging and rotating a sapphire about its own longitudinal axis while in said grinding'position, means mounting said stop, a cam engaging said means and operable through the same to move said stop and permit the wheel 'tocarry the sapphire out of grinding position, means for operating said cam in predetermined relation, and an adjustable means whereby such timed relation may be varied.
- FRANK L. CAPPS.
US250668A 1939-01-13 1939-01-13 Sapphire grinding means Expired - Lifetime US2248955A (en)

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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2665526A (en) * 1951-06-25 1954-01-12 Union Carbide & Carbon Corp Automatic grinding machine
US2745903A (en) * 1952-05-10 1956-05-15 Gen Dynamics Corp Signaling system
US9154678B2 (en) 2013-12-11 2015-10-06 Apple Inc. Cover glass arrangement for an electronic device
US9225056B2 (en) 2014-02-12 2015-12-29 Apple Inc. Antenna on sapphire structure
US9221289B2 (en) 2012-07-27 2015-12-29 Apple Inc. Sapphire window
US9232672B2 (en) 2013-01-10 2016-01-05 Apple Inc. Ceramic insert control mechanism
US9632537B2 (en) 2013-09-23 2017-04-25 Apple Inc. Electronic component embedded in ceramic material
US9678540B2 (en) 2013-09-23 2017-06-13 Apple Inc. Electronic component embedded in ceramic material
US10052848B2 (en) 2012-03-06 2018-08-21 Apple Inc. Sapphire laminates
US10406634B2 (en) 2015-07-01 2019-09-10 Apple Inc. Enhancing strength in laser cutting of ceramic components

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2665526A (en) * 1951-06-25 1954-01-12 Union Carbide & Carbon Corp Automatic grinding machine
US2745903A (en) * 1952-05-10 1956-05-15 Gen Dynamics Corp Signaling system
US10052848B2 (en) 2012-03-06 2018-08-21 Apple Inc. Sapphire laminates
US9221289B2 (en) 2012-07-27 2015-12-29 Apple Inc. Sapphire window
US9232672B2 (en) 2013-01-10 2016-01-05 Apple Inc. Ceramic insert control mechanism
US9678540B2 (en) 2013-09-23 2017-06-13 Apple Inc. Electronic component embedded in ceramic material
US9632537B2 (en) 2013-09-23 2017-04-25 Apple Inc. Electronic component embedded in ceramic material
US9154678B2 (en) 2013-12-11 2015-10-06 Apple Inc. Cover glass arrangement for an electronic device
US10324496B2 (en) 2013-12-11 2019-06-18 Apple Inc. Cover glass arrangement for an electronic device
US10386889B2 (en) 2013-12-11 2019-08-20 Apple Inc. Cover glass for an electronic device
US9461357B2 (en) 2014-02-12 2016-10-04 Apple Inc. Antenna on sapphire structure
US9225056B2 (en) 2014-02-12 2015-12-29 Apple Inc. Antenna on sapphire structure
US9692113B2 (en) 2014-02-12 2017-06-27 Apple Inc. Antenna on sapphire structure
US10406634B2 (en) 2015-07-01 2019-09-10 Apple Inc. Enhancing strength in laser cutting of ceramic components

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