US2455597A - Grinding wheel - Google Patents

Description

endf of the shaft, an intermediate web extending mAnother object lof the invcnticnistcprcvide outwards fromthe hub, anda cylindrical sleeveaierindins whcclcfthetype andcharacter under like rim `having the central portionethereof "conL vconsideration in which the ducts constituting the `jacent portion-z of :the ..work wpfeceg; 11n` `mamme lducts constitute orforrn scoops which directfthe it has `been `foumrtioot whenthe coolant is apcoclahtldowhwards @message` or owthroush pliedinthismanner itdoesinot form acontinuth ducts-1 `ous lni under `the abrasivetring due tofthefact L l\iAIlOhel'fObject 0f theinvention S` t0 prOVide s eArENroFlr-'lcs LeopoldH." etzgerand Wilson B. Muse, Chicago,` N i t `ollli;andFred-.1.141Pease, Wauwatosa. Wis.,asi `signorsmbmimesne assgnrnentsftoSuper-Ontw, t t ,lnc., Ghicago,` llLLa corporation of Illinois u `The "present invention" relates i `to*l grinding i in which the coolant supplyingmean's lis adapted wheels. "More particularlytheinventionirelates to receivethe coolant fro1n1-`a`` downwardly e1;- toithat type ofgrindingfwheelf whichfisifadapted tending stationary supplyit'ube `that is disposed :to bedrivenat a comparatively higilifspeedbyfwa'y inlclose proximityito thefpower driven shaft for, of a dependingpower drivenl shaft, `servesfto is the-glwheelland projectsinthe direction of the formasmooth surfaceoradesiredorprefieren upper surface `of the webcf the Whcclyand is mined contouron a workpiecegsucmfor example, in they form of an annular series of `spacedfapart. asf a lens;` and as its principal coniponentslor t ducts whichware` formed in, and extend downparts comprises a hub havingicentrally disposed wards completely through, the `outer margin means wherebyit may beconnected to the lower 1i() pltiO 0f the Wheel `W611inected to the outer lniarvginalflportioni of 4the web `COOlltfSill-lilying mliarespced equidistantly and embodyingat its lower end -a "concentrieally F15 apartandaredownwardly inclined ina direction positioned `ringL of abrasivefmateriah such as opposite to the direction y"offrotatioriof the wheel.

diamond particles in la-rnetailicor otheririatrix. i Another 'objectof the invention `is t0 Provide t `In` using i a "grinding` wheel fof 'this type iii-,1 is a fgrindingiwheel of the aforementionedcharnecessary to einpmy a @01am in `order ftcpreacter in which the portions of the upper surface vent overheatingoffthevringof abrasive material "20 OfiheWeb that alediSpOSedbCWen ihupper and cracking of the workfpiecefespecially when endsof theducts aredownwardly inclinedin a the latter is aliens blank whichi's formed ffgmgs, directionwopposite to `the `direction of rotation It has heretoforebeen #proposed "to apply the `ofthefwheelinorder that the coolant after-dis- `coolantioy drectingitlin stream form against the Charge frdmithe supply tube is directed intothe 'outerperiphery ofdthe abrasivering' and thisbupper ends ofthe ducts `and such ends of the that thewwheei in response tocldriveoauses Ythe `-30 al grindine wheel `0f `the typ'iand character un- -ooo1ant `to `rotate withi the wheel and` now outldcr considerationfin which the inner peripheral 'Wards by centrifugal force Wheni-thecoolant portion bf thellppel endof ther sleeveelike rim doesnot form a; cntinuousi mmoundei-pthe Awunder-cut in order toprovideva downwardly abrasive ring there is a marked orpronounced aled annular surface which, in "connectionwith tendency for theringito heat andlresultiin operation?of` Whe "'grirldirig fWllefl,` lConfilfies"thel cf.A

cracking or fracture ofthework piece.` iFurther- 600111111"` that is `dishhlged bythe suppli/Y "lip` S0 more, the ground work piece particleshave altenthat itfows for the most part` into the upper ends dency to remain `under `the ring and hence Ofthe ducts* fnslillcng` the coolant `Supply `scratch the Work piecefduringV drive ofthekwheel 'lfiml's-I and precludethe formation of the desiredismoom "40 I" "fA `further Object IOf` the invention iS G0l Provide surface on theworlrpieme.:` 1 l t "i 5in"connectionwith` a grinding wheel of the type Oneobjectof the instant nventionlislthe pro- *under consideratiom la novel 1 `hood "structure vision, `in connection lwith i a grinding` whee1 1 of which precludes `thecoolant,` prior tolpassage into the :type under :considerations `of ,novel means the duotafromnowing outwards overthe upper whereby lthe1coolant1is supplied aroundlthelower 5 end` ofwlthewrim in `response `to the action of cenportion of the innertperipheryyofi,thecylindrical tifugal force. i "c 1i sleeve-likerim in" order that it sflows outwards I i `Axstili further object of the' invention iis t0 Drobyfcentrifugal forceiunderlthe abrasive ring and wideagrinding wheel whichtis an improvement serves not onlyito provvide` a continuous nlm `beupon,andneliminates thedefections'of, `previously tween the ring andthe `subjacentrportlon uof-the 1150 designed grinding wheels and is characterized by work piece and thusenecttmaximum ooolinamut :higheftlcicncv` as Well as `simplicity of design: also to fiushxoriwash awayy the; ground` particles s `Other objectsioffthezinvention andthe various of theV work piece. i* i advantagesilarid 'characteristics' of the present i 1 `Anotherrobject of `theinventioruisto'iprovide Igrindingwheelwilifzbeapparent-froma consider- `aygririding wheeifoithe;lastimentionedl character 56 ation"of:thewfollowinswdetaild"description? f-l as the coolant reaches the -lowefinner edge ofthe ring I 3 of jabrasive material it" is `flung-outwards by centrifugal i force under and outwards across the ring.` The coolant; in response -togthe faction of centrifugal force,\fo`rms a continuousffilrnibe` tween the lower surface of the ring'and thesubjacent portion of the work piece andnot-on-ly-ef fects efficient i cooling of 'the-ring; butalsofserves to flush or wash' .awayfthelA particles ,whiohyare ground from the work piecev The -ducts-fI-I Eextend approximately at an angleiof-"l` 60 .withIre-i spect to the` lower `surface of-lthe wheel `weicht;as' shownin Figurefi, andare downwardly-' inclined in a direction opposite to the direction of-rotation of the wheel. Bvso inclining the :ducts thecoolant is forced downwards lthrough l the ductsl byfa cam or wedgetype" action. Therportionsof 'the upper surface of the web E that are disposed lbe'- tween the upper.r ends of the ducts vI I are downwardly inclinedf in a ldirection opposite i to i the t direction of rotationlof the :wheelinorderithat the coolant,` after` discharge;` from theflsupply tube I2,` is efficiently` and effectively directed finto the upperfends of the ducts fori downward `iiow through the ducts onto1 the lowerportion ofthe inner periphery `of the rim'I.` By reason ofrthe fact thatithe trailing portionsof the upper ends of the ducts are ata higherleveltorfelevation thanrthe lower or trailingendsiofwthe aforementioned portions ofthe upperfisurfaceof the web such portions ofthe upperends of theductsform scoops which faceinvthe directionofdriveor rotation of the wheel and operate f during drive of the"wheel to directthe coolant -downwardsfinto and through `the ducts Preferably ithe outer portions of theducts are in substantial'"align ment with theflower` portion of theinner periph`` ery ofthel rimwJAs-ishown in! the drawingV1 the upper and lowerl ends ofthe ductsare spaced equidistantly from the" axis of the wheelfand fas "A a result the `longitudinalcenter-lines of theducts lie substantially in an imaginary cylindrical-euri face `which is concentric-with the cylindrical rim 1. Because ofthe specific` arrangement or positioning of the ducts Ilfthe coolant is discharged in such manner o nto the inner periphery of the lower portionfof the rimthat itswirls around and substantially" completely: covers saisit inner 1. pe-

riphery. In order to confine :thefcoglantg-sp-that l after discharge thereof from the supply tube it flows onto the uppersurface of the wheel web and into the ducts without"appreciable-:urpmnouncedxspillage over the upper projecting 4portion of thefrim, the innerperipheral portion of theupperend of the rim is under-cut inforder t0 provide a downwardly iiaredf annular surface` I 5. `The latter overhangs to a'small extent the `upper ends of. theductsfand confines the coolant onfthe upper surface ofthe wheel web so thatlitdslpreeluded from being flung outwards by centrifugal force. t

In addition to the parts heretofore mentioned the grinding wheel comprises a composite hood structure I6. This structure serves to prevent `the coolant from fiowing outwards over the up-` per end of the wheel rim 'I and comprises a lower member I1 and an upper member I8. The lower member is hemispherically or dome shaped and is preferably in the form of a sheet metal stamping. It overlies the grinding wheel proper and embodies in the upper central portion thereof a circular hole I9 through which the power driven shaft s extends. As shown in Figure 2, the hole I9 is in concentric relation with the shaft `and the diameter is approximately twice that of the adjacent portion of the shaft: I A cylindrical flange 20 is connected to, and extends upwards from; Ltheiholedeflning portion of the lowerv hood rrieiberII-ll `Thellowermarginal portionof such member surrounds the upper end of the VWheel rim"1 and 'is removably secured in place by way efuscrewsl 2I.` `.The latter extend through holes inthe` lower i marginal portion of the hood `memberfl Tand-into radially `extending threadedfsock` ets 2 2' the'upper `end of. the rim. @The upper member Iii'fof the hood is stationary and` surrounds @the-*shaft 's1 at a `point above the lower member I'1 `oi-the hood structure. It is suitably supported from above and embodies at its lower end an externally Adisposed inverted U-shaped fian-geilfwhich; as shownin Figure 2,9isarra`nged inistraddlfedfrelation `with the ange 20 onthe upper `central Ipoxtion` `)`f the lower member I'l'.y The" supply tube `I2 forfthecoolant extends be` tween the upper member IB andthe shaft s. During use of the grinding" wheel the `hood struc` tnreserves;aspreviouslypointed out, to prevent out-flow of the coolant over the "upper end -of -the wheel"`ri`m` l. `In connection `with removal ofthe wheel proper Ifrom the shaft s` the `upwardlyipro jectling flange 20 on the upper centralI portion of thefloweir member I 'I `slides out )of intertting relation withthe finvertedrlJ -shaped harige 23` on the lower end of `the upper member I 8 in connecl tion `irvith downwardshift of the wheel proper;

During a grinding operation the work` holderh "drivenv in a couhterclockwise direction by the drive sl'ralftfyd` and the grinding Wheel is driven `in a 'clockwise direction and is alsoi` oscillated or rockedfblaclfand forth over the work piece by the power driven shafts as hereinbefore pointed outI I'n'r ponse" to "drive and oscillation of the grinding" `iivheel the Vring" i3 `grinds the upper surface of theworkpiece so that ithas the desired"contour li'iinfd` polish" `or smoothness. The coolant whihisfsupplied in stream form onto the upper surface of the web Bof the wheel bythe supL ply"tubel2"`flow`s downwards over the portions of the flipper" face of the web thatarebetween the -`end s "of the ducts I2.` 1 It then enters and `flows downwards through the ducts. After flow t ingthrough `the ductsjthe coolant swirls around the lower" portion of theinner periphery of 'the wheelrim and finally in response' to the action of *centrifugal force" flows outwards in v lmfform under thering I3 of abrasive material. `As"the coolantows `underthe ring itcools'the latter and1 the work piece and flushes `or washes `away the-ground particles ofthe workpiece.` i

`The herein described grinding Wheel is lhighly vefficient due` to the `fact that it lincludes novel means `whereby `the coolant is supplied faround thelower portion of the inner periphery ofthe cylindrical Asleeve-like rim` in` order that it flows outwards by centrifugal force under the abrasive ring and serves not only to provide a continuous film between the ring and the subjacent portion of the work piece, but also to flush or wash away the ground particles of the work piece. Because of the design and construction of the wheel the latter may be produced at a comparatively low cost.

It is to `be understood that the subject grinding wheel although it has been illustrated and described in connection with the grinding of a work piece in the form of a lens blank, has other capabilities of use. It is also to be understood that the invention is not to be restricted to lthe details set forth since these may be modified within the scope of the appended claims without adonner.

departing v:from the .spirit vand scope Yof :the invention. y j.. .i

i Having thus described the invention what we claim yas new and `desire yto :secureby Letters -Pat ent fis:

:1.` A agrindingrwheeladapted to be driven about itsraxis Jin :one direction and comprising -a hub, a web .corn'iectedv to and extending outwards :from the hub,vand a cylindrical rim having 4:one portion thereof :extending around and `connected to the outerlmarginal portion of the web and in addition havingfone vof its lend portions .projecting ,in `one direction beyond one exposed surface "of the web and ,provided yon fits outer extremity with abrasive material, said web having extending -completely wheel and shaped andvarranged so that during' drive ofthe wheel it serves positively to `directinto .the receivinglend of the duct the coolant that is supplied to said other exposed .surface of the web.

2. A grinding wheel adapted .toibe drivenabout its .axis in one .direction by a substantially vertical power driven shaftand comprising ahub-having associated therewith means 'for' connecting .it to ythe ,-shaft, .a web connected to and .extending outwards lfrom .thehub and a AcylindricalIsleevelike rim having the upper portion thereof extending around and connected to the outer .marginal portion of vthe web .and having its lower .end .nortion ,projecting downwards beyond -thelower surface ofthe Web and provided at .its lower extremity with .abrasive-`rnaterial, said web having formed `therein an ,open .ended vstraight duct erranged so that the upper and lower ends lthereof are spaced equidistantly from .the axis of the wheel, inclined .downwards in a .direction topposite to the -direction of .drive of `the Wheel and adaptedto .conduct to tthe inner periphery of ksaid lower end portion .of the rim a coolant athatis .supplied to the upper .surfaceof nthe Awekrsthe -por- :tion of -the vupper surface of -the webthat-is'im- -mediately ahead -of :the upper endof the duct-being downwardly inclined in the same direction .as

i grinding --wheel adapted to .be driven about its .ax-is inv-.one directionby a power driven .sha-ft and comprising. a-f'h'ub, :a 4web -connected to and ewtendingoutwands -from thehub and a cylindrical' sleeve-like ,rim having one portion thereof extendingJ around and `connected to the outer marginal portion Fof :the web and in Vaddition `havin: one'end portion thereof projecting 1in lone direction beyond `one exposed surface of the web .and provided on Lits outer extremity with abrasive esaid web having y:means for conducting through it to the innerperiphery vof said oneend portionv of the Tim a coolant that :is 'suppliedto the cothcr exposed surface xof, the web, :saidmeans including .simiaces that fare inclined toward said one exposed :surface of the web in a direction directly orzposite to the direction of drive'of the wheelf A 4. A grinding -wheel radaptedito be driven Vabout .itsaxis ein :one direction by a power driven shaft 'and comprising la -circular body zmcmber embodyf ing :surfaces .at `opposite ends thereof, provided fabrasivexmaterial adjacent Lone yof said surithewduct in -order :that the trailing portion ofrsaid 5 upper `end .ofthe duct is Ahigher than -the leading portion and forms :afsc'oop that :facesin :theidirention of drive of the wheel and :serves Ato `direct the .coolant downwards into .the duct.l

iaoes. adapted to hav-ea duid coolant delivered .to lthe other surface, -`and :having yformed therein .between the two surfaces la :straight open ended duct adapted to conduct- :to the abrasive smaterial the coolant 'thatis supplied to 'saidothersurface of :the .body Ymember,.said-aduct being inclined from receiving end to its discharge :end in Ia direction opposite yto the direction of drive of :the wheel,` the portion of :sa-id fother surface .of the ytutti? .member .that limmediatel-y ahead of the receiving `end of `the lduct being inwardly inclined towards andxintosaid receiving end of the duct v REFERENCES CITED "The iollowing lreferencesare of record in the me 4of this patent:

Y'UNITED STATES PATENTS Number 4Name y Date 142744 Cottrell Nov. 518, 187.3 90h90!) :Johnston 'Oct. 20, 1908 1,019,304 Spencer\. Nov.. r18, v19:13 '21,82Q;58f1 Richmond et al. Aug. 25., 1931 I1;86pi92v IBuc'heister. July .26, 1932 2,338,279 JKelleher ..i .J an. 18, .1944

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