US2189242A - Device for grinding eccentricity in pistons - Google Patents

Description

Feb.6,194o. Y EDWIN E1- AL' 2,189,242

DEVICE FOR GRINDING ECCENTRICITY IN PISTONS Filed March 2, 1939 nur."

\ y INVENToRs SQ/c 50W/N,

i j lsatentetlFeh. 6, 1940 v 0' piston in the usual grinding head.4 1

4This invention Irelates 'itofa cam-grinding pistons. "i'he pisflqlwl automotive engines are ground vto anevai `shape to accommodate theI unequalfxexpansiondue toi Toneaxis than on the othergtofproduce `an oval f. s hapeof the old'cylinderis-.

` shape whinlwiunt thel newfpistpntethe'ovei f YOther objects of the invention are; toprrovii'ie device of this character which can' `bef adjusted there 'will be `no lostjmotion o'r looseness ever in the present grinding equipment Other 'objects and advantages'resid thej detail constructionof the'inventiomjwhiclifis de` 3b signedforsimplicity, economy.` and!eiiiciency; l These will hecornefmore'apparent fromthe fol-" lowing description. i

invention reference is had toV theaccomipnying drawing and throughout the description. Inthe'drawlng: Fig. 1 illustrates the invention invention. t

Fig. a is e cross-seetibn therethrough. teren en es piston is vindicated at n with its head u, wrist fichu- 40) A ffpin opening at modern #marked .012" `sertedin the centerpunch socket of the piston Fig. 21s an inner face view of oneffornxfof thefj the lathe or grinding machine with conical, lcounter-sunk center `punch `socket in` the head I4 `intofwhich the jpint of the dead"centen` j the forward faceof the :disc i6 a utapered9 center point I 9` is" forxnedpat the *enact center: 1

g of the disc and ring. center .socket 120 is'` in-` 'jdented inthe rear .facelof the ring to oneside *oitheQcenter ofthe ldisc" and ring. The amount of eccentricity ofthe sooketnfis g equal toom-half th'ediiierence desired between` l 'orthecenter punch hole in any-given piston50j? 25 during the'erindingA operation; and to provide a device whichwiu require no changes what@ the long* and short diameters" of fthe? finished each` being "marled for its oii'set asshownatfll'. The: outer face" of ieachiA disc Ycontaii'is "a gauge toprojectfronrthe frontfacethereof. u

Let `us assume it is desired?` to cistrfnlgrind4 a piston `for 1.012 eccentricity."v` gauge line t 2l is scribed across the 'headfI'L exactlyover'the .axispf thefwristrpin ope'ning.` Thedevce is` selected and itspcintl is in- A'nowr screwed towarathe pisi'zcmhehd` uhm it restsA nrmly thereagainsa but not sufliciently far to device 1from niovingisidewavs onxthefpiston and piston head.

The piston and lthefdevice are no wfinserted s in `the dead center in the socket 20 ofthe disc; thegauge line 22 on Vthe disc is turnedu into alignment with the gauge line 24 on the piston; a piece of. shim stock 25 is inserted betweenfthe chuck l0 and the piston skirt on the side `of the piston to which the dead center is eccentric; and the tail stock is tightened. This positions the piston tojone ist` side of the grinding machine center as indicated 5 the uneven heating 0f the piston. "I'his allows a `(center or chuck f orturning `or grinding opera 5 t l much closer t to be made ofthe pistons withoutV ,tions. l

f danger Vseizing when hot. ljhe usual nisi'firi `v This' invention Vconsistent e device whichmayl grinding machine is designed to grind pistons to.; be `placed between: the `pistn 'head fuwadtha cylindrical shape and cannot impart 'ovi `\l dea'dcenter I2 to oii'set thlatter'froni thecenter 1Q f Shape iilleretu. "1 Punch socket in the r"head tocause the piston to` 10 i The principal `object of lthisL invention Lis `swing or gyrate about itstrue centenas itfoprovidean `accurate device whichcanfbe placed fates beforejthe grinding "wheeler the grinder. f n a pistn ingtheus'ual grinding '"iiriachiiiel t0.Y The device Veonsist'szfof afcirciuarlf^disc*'|t"=vvith cause the piston to rotate eccentricallysqfjthat 1a threaded periphery I'ljuponwhichathreaded, t l5 r.the piston may bejground. to lesserjdiameter split, demping ring n is tm-eaddu .i `15 piston. A set of :devices of diiieringoii'sets will i be provid'ed to` 4Suit thedesired conditions,`

ine 22"acros`s9itsi'ace drawn: at right angles to' lift thejpoint I8 fronitsseatiinithe pistonicenter 49 punch socket. This adiustment prevents: the

' also prevents it from rocking ortiltingon the` by the asset eenter 11neeAendB"in ne. 1.

the disc kishollowed Vreceive a ,threaded ter axis ci thepoint.

side of the piston.

'Grinding` is now commenced, the major portion of the metal being taken from the eccentric Upon completion of this side the tail stockiis loosened and the device is given a one-halfv turn to bring the gauge lines again into alignment with the center socket onjthe opposite side, the

@with eachother; and a shim 'is changed to grinding is repeated piston.

the opposite` side and, the

' It has beenffound that the Irictional engage-vr andthe piston head is on a center point comprising:V a disc; a projectment between thek device ordinarily suiilcient to position,Y The set screw 23 however is provided to insure the set position; If this' screw beY tightened'after the piston is in position in the grinder its point will engage relative movement between the device andthe piston.

the piston head'to prevent innige. 5,*6, and

21 is'threaded,` and uponwhich, a

device. In this form, however, the outer iace of vand internally threaded to center point 278. .into the outer'iace oi*A the vbutton on Vthe center of kthe button.

3 2 by means oiwhich the ftenen of the button 2a. when of Fig. v.'7, the socket'isfat its yeccentricity. When yrotated one-half turn fromVV 4 Ysired to be understood that the samefmay be varied. within the scope-ot the appendedv claims,

' tion.

lsinscribed across the button the disc 26 at .each

The second form of the device is used similarlyv to the `first form. lIn this form, however, the amount of eccentricity may that position the socket 30 becomes concentric While specific Aforms of the improvement have been described .and-illustrated herein itis de without departing iromvthe spirit of the invenj Having claimed and desired secured thus described the invention; tenet is by Letters Patent is: l .Y 1. A device ior supporting workeccentrically on a center-point comprising: a disc; a projecting point lonone face of said disc for engaging the work; a socket on the other face of the disc for engagement with the center point, said` point and said socket being out of axial alignment with the work; a socket vfor engagement with for the oppositeV` side of the hold it p roper adjusted 7, an alternate form of there'.

.7 device isshown consisting of a disc upon which 1 sa. split ring reenter point V28 is formed. similarto the previous button 29 whichis tightly threaded therelnf The hollow in the disc is eccentric of the disc Vcenter and eccentric ofY the A center socket 30 is .drilled Y 28 and disc 26 which, et

. course, places the socket 4toone side oiethe cen- The disc 26 is provided Vwith -wrench openingsil `and the button is provided j Awith wrench openings Y ing point onfone face through the center i socket 38 on theaxisoffgreatesteccentricity ofv ythe latterand gaugelines 34 are inscribed on be regulated by Vro- Y in the positionY point ci lgreatest aisama 2. A device for supporting work eccentrically on a center point comprising: a disc; a projecting .point on one ace of said disc for engaging on the other face of the disc the center point, said point andr said socket being out of axial alignment peripheral rim member about saidvdisc, the projection of said rim member beyond the face of the disc and about said projecting point being adjustable. 1 4

3.-A device ior supporting work eccentrically ing point on one face of said disc for engaging the work; a socket on the outer face of the disc foi-engagement with-the center point, said point said disc, the projection of saidrim member beyond the face of Vthedisc and about said projecting point being adjustable; and means for preventing relative movement between said device .andsaid work.

j 4. A device for supporting work eccentrically on a center point comprising: a disc; a project- Ting point on one face of said Adisc for engaging the'work; fa hollow'in the other face of said'disc,

' said hollow being eccentric of vthe center of. said disc andy said projecting point; a button -iitted intosaid hollow; a* socket in the outer face of said button Aforv engagement with the' center point, said' socket being eccentric with said projecting point.

l5. A device for supporting work eccentrically on na center point' comprising: a disc; a projectof said disc for 'engaging the work;Y a hollow in the other face of said disc, said hollow being eccentric of the center of said disc andi said ,projecting point; a button fitted of saidfbutton for engagement with the center point, said socket being eccentric withs'ail profjecting point; 1 about said disc,

Vber beyond the face ofY said disc'and about the Vand a peripheral rim Vmember the projection of said rimmem'- p iojecting'- point being adjustable.

6 A device for supporting work eccentrically on a center point comprising: a disc; a projecting point on one face of saidjdisc. for engaging the work; a hollow in the other faceof said disc,

saidehollow beingeccentiic oi Vthe center of said disc and said projectingpointya buttoniittedV into. .said hollow;.a socket in the outer face of said button for engagement with the center point,

-said socket being eccentric with said projectingd '-point; and la" peripheral rimmemberY aboutsaid ao-l into said hollow'i a'socket in the outer ,face axis of greatest eccentricity of the button socket in the disc. Y s

disc, the projection of saidzrim member beyond the face of said disc and about the projecting point being adjustable;v and means for relatively rotating said button and said disc `to adjust the degree ofY eccentricity between said socket and said projecting point.

e a s ERIC EDWIN.

MERLE PlElTEl'tSON. u

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