US2654189A - Apparatus for grinding noncylindrical surfaces - Google Patents

Description

Oct. 6, 1953 E. R. DUNN ET A1.

APPARATUS FOR GRINDING N ONCYLINDRICAL SURFACES Filed Feb. 2, 1951 ATTORNEY Patented ct. 6', 1953 APPARATUS Fon GRINDiNG NoN- cYLmDmcAL summons- Elman R. Dunn and Donald F. Price, Waynesboro, Pa., assignors to Landis `Tool Company,

Waynesborhoi-Pa. j

Application February 2, 195]., Serial No. v209,160

This invention relates to cam grinding ma- A chines, particularly to the type of camgrinder which automatically grinds successive cams lon a camshaft.

An object of this invention is to provide means for automatically grinding successive cams on a..

camshaft where said successive cams are tapered in opposite directions.

A further object is to` provide means forchanging the angular relation between grinding wheel and work each time an unground cam is movedi into grinding position.

A further object is to provide hydraulic means for swivelling the wheelbase.

A further object is to provide a swivel point ,sideof lever 40vand pivoted at 5|.

located behind the short The upper end of lever 50 is connected to a horizontally Arsecond lever 50 is slidable member 52l in which a plunger 53 is V-slidable vertically. The lower end of lever 50 is connected to -reversing valve 20. When I plunger 53 is in a notch, it acts through memy tral position.

located relative to the grinding wheel so as to; l

cause a minimum of' dislocation of the grinding wheel relative to the work when swivelling from one position to another.

The drawing shows a combined electric, hy-

draulic and mechanical diagram showing the esi-i` sential elements of the invention and their relation in the combination. c.

Numeral I indicates the work carriage of a grinding machine. The motor for traversing said carriage consisting of a cylinder Il and a piston l2 slidably mounted in said cylinder. A piston rod I3 on said piston may be attached to said carriage in any suitable manner (not shown). A work piece I4 is rotatably supported on carriage I0 by headstock l5 and footstock Fluid under pressure for moving said carriage is directed to one side or the other of piston I2 by a reversing valve 20 through lines 2| and 22. Another portion 23 of valve 20 performs a function to be described later. Y

A by-pass valve 30, when in central position, connects lines 2| and 22 through lines 3| and 32 respectively so that carriage I0 may be acto engage pins 55 and 53.

ber 52` to locate 4reversing valve 20 in a neul A pin 42 in the short side of lever 40 extends through. a hole 54 in lever 50. Said hole is about -three times the diameter of the pin 42. A pair of pins 55 and 55 is'slidably mounted in lever 50 so that they extend at right angles to .and engage pin 42;` Movement of pins 55 and 55 is restrained by'springs 51 and 5B, secured to lever 50 near its pivot point and extending downwardly Thus, when lever 40 is moved to right or to left, pin 42 causes a ycorresponding movement of lever 50 about its pivot I.. Theupper end of lever l50, being connected` through sliding member 52 to plunger 53, might cause a lateral movement of said plunger except for'the fact that a reduced portion 59`on' said plunger is normally in engagement with any one of several notches 60 or 50' in a spacing vbar 5| on carriage 0. `When so `restrained, the movement of lever 40 results only Y in shifting the pins 55 and 55 against springs "'51 and 58 respectively.

When lever 40 is placed in theright-hand po- 4sition, pin 42 pushespin 55 to the right against spring 58. When plunger 53 is withdrawn from the spacing bar, lever is released; and spring 58 causesit to move in a counterclockwise direction and shiftv reversing'valve 20 to the right.

` The carriage moves-from leftl to right; and when fthe plungerdrops in the next notch, the movef mentv of the carriage carries it a short distance tuated by hand without being obstructed by a locked body of uid. Said by-pass valve also has another section 33 that directs fluid to a mechanism, which will be described later. j

Said reversing valve and said by-passvalve may be actuated simultaneously throughca combination of levers consisting of a U-shaped lever i 40 having one side longer thanl the other,` the longer side having a knob for manual actuation of said lever. Said lever is pvoted; at the lower left-hand corner thereof on a shaft 4|.

inf the same direction so that through sliding member 52 it shifts lever 50 in a clockwise direction and moves valve 20 to the left until it shuts offY the supply of Afluid to cylinder to stop thecarriage inA position for grinding another cam. y Y

. Thel means for manually withdrawing plunger 53 consists of a lever |00 which is loosely coupled I to bell-crank |02, and both are mounted on shaft -g I0|.` Bell-crank |02 extends horizontally into opsoY erative engagement with plunger 53, and arm |03, also a part of bell-crank |02, extends downwardly between valve member |04 and piston rod |05 from pston'l05 and cylinder |01. A further extensionof arm |03 is connected to a yoke |50, which is slidably connected to adjustaecaiso ing screw I6I in the stem |62 of valve |63. By this arrangement, lever |03 can be moved to withdraw plunger 53 and at the same time shift valve |63' only enough to place it in the lefthand position shown in the drawing. The extension ci 'arin A|03 also serves to engage exhaust valve |10 to shift it to the left against spring I1|.

Valve |04 controls the movement of the grinding wheel support, and also serves as a medium for moving arm |03 and associated parts in a counterclockwise direction by 'means f spring |08. When so moved, arm I 03 through bellcrank |02 moves plunger 53 'upward that the reduced portion 59 thereo'fmay erltei1 one f the notches 60 or 60 when properly aligned. When arm |03 and plunger 53 arev actuated by timer piston |08 to withdraw plunger 53 from notched bar 6I, uid for operating said time 'piston -is directed to the head end of cylinder |01 by valve l"|` which is sinnedv to a closes positron by a sei-mis ll It against the action of spring H1, during actual grinding time.

sii-encre 'l It is energized or eeeriergizsd, as the oceasion requires, at predetermined intervals by 'mansof a timing mechanism IIB. Fluid under pressure for operating' the various mechanisms is 'supplied by s 'pump mt 'through une m te 're- Versingvalve 27|)Y from which it is directed alternately through lines 2 and l22 t'o opposite ends of cylinder I Line, |23 connects line |2| with valve 104 around which Hui-'d passes through line |24, valvev I 'lfhand line |26 to portion 23 of rev ersin'gvalve 20` From lines |24 and |26 a supply 'of fluid under 'constant 'pressureis thus alvv'ays available at said reversing valve, from which it 'might be directed'alte'rnately through line |21 or |28 to line |29. y Fluid underpressurefin line |29 acts on valve |30, :shifting it upwardly and uncovering line |31 leading tothe left-hand section 33 of by-pass valve 30. In any position of saidby-pass valve except the Aleft-hand position, "said fluid 'would be directed through line |32 to the left-hand end fof valve '|"I0. The forc'e 'ex- "e'rt'ed n said valve jby 'said 'fluid plus that exerted in the sa'mefdir'ec'tin by 'spring |135 is greater than thev pressure exerted against the opposite 'end 'andx therefore, shftsfsaid valve 't'o the right.

Fluid 'fron llin'e "12| is also directed 'thrbugh Iline |40 to the vlevait-haiti end of cylinder |01. Prfes'sure'is available constantly in this end `of the cylinder'so that vvhn the opposite end is conn'etedto an eihaust passage, the piston will be 'mvedto -the right. A l

Another supply of ffluid under .pressure vfrom liiie |2I. passesthrough line I4| to solenoid-operated valve `I I5. I When said valve is in the Vrighthand position, it -directs said fluid through line 142, check valve |43, and line |44 to-thehead fend of cylinder |01. When bypass valve 30 'is in the elett-hand position, the uid supplied tothe lefthand end of valve 4I I0 `is block-ed; `and said valve remains in the A.position shown. In this posi-n tion of valve I|0, pressure is admittedrto lines |42 and |49 through valve I I5, and thence through valve |43 to line I44to cylinder |-01.

a wheel support |8I, which in turn is slidably' mounted on slide member |82. Slide member |82 is slidably mounted on a, bed (not shown) for swivelling movement about a vertical axis |83, which passes through the central plane of the grinding Wheel at a point between the grinding wheel sp'ndle'and the point of contact of the wheel With the Work piece. The swivel point is preferably as close to said point of contact as circumstances permit. The means for moving Wheel support IBI toward and from the work consists f a rapid feed piston |90 and a slow feed Vpiston |91. This type of feed is described in det'ail` in Patent No. 2,313,479, granted March 9,1943.

The means for swivelling the slide member |82, and Wheel support |8I consists of a cylinder |95, lieunted on a bed (not shown) and having a piston |95 slidably mounted therein. Piston rods |91 and |98 extend through the ends of said cylinder to engage brackets |99 and 200 on slide member |82. Adjusting screws 20| and 202 determine the extent of movement of slide member |82 about swivel poi-nt |33.

Operation Assuming carriage I0 to be in the extreme leithand position with portion 59 of plunger 53 against stop 32, lever is moved to the right. Valve 20 is shift-ed to the right also, as is valve 30. With lever 40 in this position, projecting mem-ber 80 thereon closes headstock limit switch 8|, energizes relay `8,3 which closes contact 84 to complete the ycirmiit to headstock :motor S2. In the rightehand position, valve 20 directs fluid under pressure from line |2=i through line 2v2 to the head 'end of cylinder =|I., causing piston I2 to move carriage l0 to the Vright until portion 59 of plunger 53 drops 4into the rst notch 60 'in re- 44) spense to the action of Spring |08 transmitted As soon asby-pas valve -3 0-is shifted to central for right-hand position, fluid under .pressure from line I3I is directed throughline |32 to shift -valve |40 tothe right, connecting the-headfend-offcylinder |01 through line |44 and'line |45 with line |48, tvhich is an exha-ustipassage, thus permitting the constant supply of fluid under .pressure in line I4 0 to resetpiston |06.

A grinding wheel is rotatably mounted in V15 through valve |04, :arm l0/3 shaft |0I, and arm When .portion 5'9' of plunger 53 drops, into the rst 'notch 60', lever |00, moving ins, counterk'C'lo'clvvse 'direction in response to the 4action of said `spring |08., Eazts through yoke |39 "to move 'along adusting screw |151 until it engages stem |02 valve |63 'and moves said valve tothe right 'so thatfballwiz, pressed bi spring 2id, slipsout of groove- 2H,` which locates said 'valve in the left-hand position, and into groove 2|2, which lo- 'Cate's l'Sd Valt/' Vill the T'g-lt hand -DUSOIL Counterclocliwise `rific'ivem'ent yof lever |330 releases valve |10, r\i1hir:ii'i'sin'oved'to its right-hand posi- 'tin by "Spring 171|. :In tllis position, fluid from the rod end of cylinder y|| 'preventedfrom disdhfajrgin'g tliifeugihfline "|12 and through said valve "to exhaust passage |13. Line |12 is connected to Eeirliaillst |13 `thl'oligl'i "throttle valve 'ITZL 'This cushions the stopping of the carriage after f'plu'iiger 59 drops into ione of the notches in Spacing barili-"i rights-hand position of valve F63, fluid under pressure'frm pump |2`0, Iine I 2 4and line 22|0-1seoi1'iiezted 'toline `Y2`|5, leading to the lower fend of icylindei F and lcausing Lpiston F96 to fmove upwardly ltoferfgage bracket T99 on slide lmember 182, thus JShiftingfsai'ci '-vvheel support 'in a-counterclockwise `-direction to place Wheel |80 -m thefdottedfl-ine positionshown for'gri'nding aetapered surface correspomiing "to 'the angular .posztlon "of the :grinding 'vvheel 1F80. 'When A'slide tmember '-If82 is, 'thus 'swivelled guide 'surfaces for sald supporufwhichlareon said slide |02, are v Valso shifted so that, in the new position. the Wheel fri may be fed in a direction at right angles to the tapered surface which it is to grind.

Carriage l continues to move after the plunger has entered the notch until the side of the notch engages said plunger, shifting the plunger to the right. This movement is transmitted through sliding member 52 to lever 50, moving said lever in a clockwise direction and shifting valve to the left until line |2| is blocked, thus preventing further flow of uid under pressure to cylinder |2 and stopping the movement of carriage I0.

As indicated above, the counterclockwise movement of lever |00 is effected by spring |08, shifting valve |04 to the right in engagement with the extension |03 of lever |00. In the righthand position of valve |04,-iiuid under pressure from line |2| enters said valve through line |23 and is directed by said valve through line 220 to the head end of the piston |90, initiating the rapid positioning movement of wheel support |8| in a direction determined by the position of slide |82. At the same time, a differential pump type :duid supply, such as shown in Patent No. 2,509,368, granted May 30, 1950, serves to supply fluid under pressure at a measured rate to the head end of slow feed piston |9|. Said system consists of two pumps 230 and 23| which may be of different displacement or operated at different speeds so that pump 23| discharges a supply smaller in volume than pump 230. The discharge end of pump 230 is connected through a line 232 to the intake end of pump 23|. Another line 233 connects line 232 with the head end of cylinder |9| and supplies a small volume of fluid thereto at all times, which is the difference between the output of pump 230 and that of pump 23|.

It should be noted here that lever 50 is moved in a clockwise direction while lever 40 remains stationary in its right-hand position. This movement of lever 50 while pin 42 in lever 40 remains stationary causes spring 58 to be placed' in tension against pin 56.

When valve moves to the right, the connection between lines 3| and 32 is blocked so that fluid under pressure will not be conducted to both sides of cylinder I2. At the same time the left-hand section 23 of reversing valve 20 directs fluid under pressure from line |26 through lines |28 and |29, valve |30 and line |3| to left-hand section 33 of valve 30. With valve 30 in the right-hand position, fluid from line |3| is directed through line |32 to the left-hand end of valve i0, shifting said valve to the right to connect line ii with line |48 leading to valve |04, which connects said line and, therefore, the head end of cylinder |01 with an exhaust passage.

The head end of cylinder |01 being thus connected with an exhaust line, the uid under pressure always available in line at the other end of said cylinder moves piston |06 to the right until stopped by adjusting screw |09. This permits the above-described action by which plunger 53 engages the first notch in the spacing bar.

After carriage |0 has been positioned for the grinding of the first cam, timer ||8 may be started by any suitable means, such as movement of wheel base |8| to grinding position, to determine the duration of the grinding operation or any part thereof.

At the end of the predetermined period, said timer deenergizes solenoid H6; and valve ||5 is moved to the right by spring In this position of valve ||5, the Afluid under pressure in line |4| is directed through line |42, check valve |43, and line |44 to the right-hand end of cylinder |01, moving piston |06 to the left. This movement of piston |06 causes arm |03 and associated parts to be rotated in a clockwise direction to withdraw plunger 53 from the first notch 60 in spacing bar 6| and also to shift valve |04 to the left against spring |08.

In the left-hand position of valve |04, fluid under pressure from line |23 is directed through line 240, line 24| to the rod end of both of the cylinders |90, and |9| to cause withdrawal of wheel support |8| from grinding position and resetting of slow feed piston |9|. Fluid under pressure from line 240 also passes through line 242 to dresser valve 98. However, no dressing operation occurs until all the cams on a shaft have been ground, at which time valve 90 is shifted by solenoid 95. This operation will be described later. y

The clockwise movement of lever |00 also serves to shift yoke |60 to the left. Near the end of its movement in this direction, said yoke picks up the head of adjusting screw |6| in valve stem |62 and shifts said valve to the left-hand position shown. In this position, fluid under pressure from line 2|0 is directed through line 250 to the upper end of cylinder |95, moving piston |96 downwardly so that piston rod |98 engages bracket 200 on slide |82, shifting said support in a clockwise direction in the position shown in the drawing. In this position, grinding wheel |80 will grind the next cam on the shaft to a surface tapered in the opposite direction to that of the rst cam.

Because of the tension in spring 58, lever is rotated in a counterclockwise direction about its pivot 5| to shift valve 20 to the right and sliding member 52 and plunger 53 to the left out of alignment with the notch from which it has just been withdrawn. The previously described indexing movement vis repeated, carriage I0 moving again to the right until the plunger drops in the next notch. The next notch is not as deep as the first notch 60', and as portion 50 of plunger '53 drops into notch 60, lever |00 moves `in a counterclockwise direction; but because of the fact that notch is not as deep as notch 60', the movement of said lever is limited so that it does not move far enough to shift valve |63, which remains in the left-hand position.

After grinding the last cam on a shaft, lever 40 is moved manually to the left-hand position. This movement releases headstock limit switch 8|, shifts valve 06 to the left-hand position and puts spring `5l in tension. `Valve 20 remains in central position. y

Opening switch 8| deenergizes relay 03 and opens the circuit to motor 82 through contact 84.

As carriage 0 moves into position to grind the last cam, dog 60 on said carriage engages dresser limit switch 5|, energizing relay 02 and closing contacts 03 and 94. Closing contact 94 completes a circuit parallel to that through contact 84 and maintains motor 82 in operation after the contact 8d has been opened. When carriage l0 returns to its left-hand position switch 0| is released and motor 82 stops.

Contact 03 completes a circuit to dresser solenoid `.05 to initiate a wheel dressing operation similar to those described in the above-mentioned patents. Said solenoid shifts a valve 9B to direct uid under pressure through a reversing valve alternately to opposite ends of a dresser cylinder A piston l2 in said cylinder has a piston rod ||3 on which a dressing diamond ||4 is mounted for dressing the grinding wheel |80,

- wither..avalv ef .plunge uid und er. pressure through line M42" avaiabieiintil @dem sijn ashafthasbeenereuhi ma, fluid is directed ugh une 24u and 242 teeeididreeeiee mechanism! e; With valve Sicili. thetleitfhefid Siielr lie Connection betweenlinee. 3.11 and .3251s. blessed so as .to @avec fluid. under @essere teder threesh line 2 I .tothe rishtrhenel end ef stnden! I.. also in this position the leftfhand' section` 33,9; 'valve 3 @Delis .line man.. 'nting new oi fluid under pressure to the leiten Lof .valve lill' so tltsid valve. remains .in sie testina shcwn.

When,tin.1.e.1i...1 le. fsnetiens grinding. Oneretien.- .e111 the.. last returned to the right-hand position di 14e, line. Mite titanes@ enel-refinements '91 mvhssist'en. llliteshifi relie siate-:tile left and withdraw plungerY tafiom ecaeieeiierit The withereveie Said plunger perm. .e Spring? 5l to Shiftlevec, in ,clockwise eireetieliineriee valve 2e .te theieitand dieetiee Huid under .Pree- Sre. freni line @12J .threiish line? 'ate ihe,..1isht heidte-l .0f cilinder 1,4 l Pieten: it :arid/.tentate #.0 .Iii-Ove' te the left. but plunger. A..53 .S-ivrerented freii1. i.eppirisiutatheieeiehee r6.0. dermatitis movementlbecaiisejvalve il n .has remainedinv the right-hand. gestion.; .thusfmaiuteirins -rressure ef fluid-fen .the hee.. .smi ef cylinder. te? thretish lines |43, l545`to valve H and from valve `I {llto line |48 to the exhaust connection Ain valve .104. The carriage, thereforacontinues inc move to the leituntil plunger 53 is, engaged by stop.$ 2, shifting said plunger slightly-to the left,f,tand' through sliding member?,.rotating levers!) ina counterclockvvise direction'to return valve 2i) to a neutral position and thus shut 01T the supply of uid to cyliriderilt` ,v i

. hen: z'afriage i!! begins to move tothe left. limit' switch. Si is .re.leased opening contactsY 93 and 9 4.. Openingmc'ontact 94 breaks the circuit Vto motor. 32@ .;Iflowever, .contact- `lill is vbypassed through Contact 9 6, which is actuated .by a cam 9'!V on the headstock spindle, `This cam `engages the contact only vvhen the cradle ha s been dropped to inoperative position, aas-described in Patent 2 ,245A1QgrantedMay 27, i941.

WhileV the .apparatus described above is .specificallyfongrinding Yst lccessive cams. havingoppositely tapered surfaces, it is to be understood that 4it'y may `be adapted to the grinding of cam shafts on which oppositely taperedcams `vare irregularly distributed without departing from the spirit of the invention.

1. In a machineof the kind described havinga bed, a grinding Wheelsupport, a grindingwheel rotatably mounted thereon, a Work support, said supports being mounted on said bd, means. for eiecting relativelongitudinal movement between said supports. means l to effect said movement intermittently vto .successively position said grinding' Wheel vand spaced portions cfa tvork: piece in operative relation, means for swiyelingrsaidgrindingmwh'eel about afverticalaxis including a nydrauiic moton land f means` fiori. actuating Esaid swiveling'meansin' timed relation the A.intera mittent movement of said carriage, includingl a Spacing bar.. said; carriage.4 having., descend shallow vnotches'spaced in accordance Withthe .Spacingof thepor'tions toY be ground, a plunger for successively engaging'thfe notches insaidspacing'bar, and control 'means actuated in conjunc- ..,.1`, u f v tion with saidlplung'er foicausingfsaid motor-:t0 movein opposite. directionsto position said grinding Wheel for grinding oppositelytapered--cams.

, 2'. In a machineof the kinddcscribed having` a bed, a grinding Iwheel support, a grindingfwl'ieel rotatably n'iunted thereon, a Work support, said supports. being mounted on said bedjtm'eans for enacting' relative longitudinal movement between .Sidlsuppotsllmeans:to elect said movement inteittefitly. .te .eiieeeeeivelv aeesitienysaid grindinsvlieel ehdtereeedrertiens ef e werk-piece in operative relation, means for .svviveling said grinding Wheel about av vertical. axis including a hydraulic motor, and means for actuating said swiyeling means alternatelyiin opposite drecilQns in timedrelation with the intermittent movement oisaid'carriage, including aspacingbar onsaid carriage havingdeepand shallow notches spaced in accordance with the spacing 4anddirection of taper of the portionstobe ground, ,a plunger for successively engaging the notches in said spacing bar, and control means including aijreversing valve connected to said plunger, :said plunger being operable when moved into .a deep notch for v swivelingmeans alternately in opposite directions in timed relation with `the intermittent movement of said carriage, includingaspacing bar having notches spaced in accordance with( the spacing oftheportions tobeground, a.V plunger for suceessivelyengaging .the-notches in said spacing bar to locate saidportions inoperative relation to the grindingwheel, and control means including areversingvalvelconnected to said plunger forcausing saidtmotor to move alternately in opposite directions.

4. In a machine of thetlind describedihavinga bed, a grinding` wheel support, agrinding wheel rotatably mounted thereon, a work support,I said supports .being slidably mounted on saidfbed,

means yfor effecting relative longitudinal movement between said supports, means to eiiect ysaid movement intermittently to successively position said .grinding .wheel and spaced portions of a Work. piece in operative relation, means for f swivellingsaid grinding wheel about a Avertical axis including a hydraulic motor, means vforaciziiating saidswivelling means alternately in opposite. directions intimed relationwith the intermittent movement of said carriage including a spacing bar havingnotches spaced to locate said portions in operative relationtodthe `grinding...wheel, ka plunger for successively engaging l saidnotchesin saidspacing bar, control means including a reversing valve for causing said motor to move alternatelyinioppositedirections, and a lost motion Aconnection betweensaid reversing y valve and V.said `plunger for f preventing...operation civ-said reversingvalve in predetermined positions of saidcarriage.

u *55.7 vIn amachineoi the kinddescribed having a. bed, a grinding wheel support, a grinding Wheel position said grinding wheel for grinding oppositely tapered cams.

ELMAN R. DUNN. DONALD F. PRICE.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 10 1,683,859 Brown Sept. 11, 1928 2,041,244 Green May 19, 1936 2,272,088 Hultgren Feb. 3, 1942 2,581,759 Green Jan. 8, 1952

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