US2386382A

US2386382A - Grinding machine

Info

Publication number: US2386382A
Application number: US443756A
Authority: US
Inventors: Raymond H Cramer
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1940-07-30
Filing date: 1942-05-20
Publication date: 1945-10-09
Anticipated expiration: 1962-10-09

Description

' 4 sheets-shee' l1 R. H. CRAMER GRINDNG MACHINE Original Filed Jul;r 30,' 1940 oct. 9, 1945.

Oct. 9, 1945. R. H. CRAMER l GRINDING MACHINE 4 shets-sheet 2 Original Filed July 50, 1940 Oct. 9, 1.945. R. H'cRAMER GRINDING MACHINE original .Fild July 5o, 1940 4 Sheets-Sheet 3 346 STA/434 Oct. 9, 1945. R, H. CRAMER GRINDING MACHINE 4 Sheets-Sheet 4 Original Filed July 30, 1940 `GAL/6F Immer/#6 MWL ela

Patented Oct. 9, 1945 te General Meters cerperatimpeaeitjMiehg a corporation of Delaware Original application Ju mary 1.6, 1943.

Divided andC this application- May 20, 1942, 'serial No. 443,756

16 Claims. ninvertion relates` A to gr -in dingV -machines and"`qinprises alllof theieatures and aspects of nove yherein disc1psed. An object of the inveii "en -iste provide an improved Asizing mechafor controlling the machining of work pieces toman) predeltern-linedl size. Another object is to provide improved means for actuating and 'reset' ting the releasable sizing levers or electric contact "making members of a sizing gauge.V Ane otherffcbject iste provideimproved means Afor actua/ting afeeler gauge as to control its engagement-, witn and se paration from the Work.

' Ifo' 'these ends and dalso tcimprove generally-A upo sistm and claimed, In itsgbroader aspects, the inven# 016e iene# znsesearil stilu'tion selected f rillustrative purposes in the accompanymg drawings in which Fgf .1 iS from elevation@ the. machine.

2 isa sectional view of a detail. Fig 3 .iS a Side view, partly in section, ef che rockable gaugemounting and associatedparts.

lfig jl is an end view of some of the elements Offge.

1if.:." 5 'i s` chiefly a.

evicesfq-fthis enaractenthe invention cone n' ,the variousmaitershereinafter described front elevation of gauging 4aridsdoine' parts being broken awayand in dfllefwo ffiegauee box. is averticalsectionloiFig. 6.

is an electrical and hydraulicdiagram 'IInsfepplQatiQnis adiyision of my applica' tion Serial Number 3,518,398 which is noW Patent nihfsin more detail.

I lhe'vvorl; surface to begaugedduring a ma'L chining operation such as grinding is herein shovv'nmfor example as a tapered surface' 2 (Fig. 4) 'on the inner race ring 6 for a tapered roller bearing which is clamped in a chuck C whose spindle; is journalied 1in a Work headjH and drivfn by a pulley 42 connected by a belt (not thro nvr/ hiena drive 'fshafflsrertendsl Thev workspaces cricca; by e were sizing feeler or forli' 'gauge G during grinding andthe work piecfis v ejectedafter' grinding by an ejector yglimied to the specific cone es, the gauge box cover kleinere- A 3 and wl i ich vshows co-operating mecha'- carrier 52? receiving the workv .piecesin 'successionyfrom a 'masazinegl the carrier heme; mounted on aslidelll] Whichfis reciprocated by a cylinder u riit 544` all mounted on a bracket 94 whosebaseZ is `fastened to the housinglllll.

When the work head H Yis adjusted (to their prcperxanglat racer/ay, surface is ground by a grindingfwheel W whichis fed normal to the surface. by afieedslidelli guided by" doyetail; waysA ci avbase plate2, the Wheel spindle preierablyibeing given a, shoriileciprocatin; by gearine in; a caSng'$0I. Dur ing grinding; the feedUA Slidey isi fed byra; .f eed. Screw ,whicncan be oper-v ateyimallually bya hand, Wheel ldjhaving a handle 676 or by pawl and ratchet; mechanism which;

is actuated by cylinder and piston units. A paWl 70510113.11 arm 710 which is pivoted to. apiston rod -l l 2 projecting from a cylinder 122 has an adjustablethrow which is first -ample for coarse feedjandthereafter more limited for ne feed. j W A `bar 'H6 clamped on the piston rod carries two;

adjlltableflimit screws "124 and 126; the first adapted to engage a stop lug 121 on the cylinder duringcoarse feeding. The other screw '|26 restricts the stroke of the piston rod Vfor ne feedingjwlien a swinging latch lever 128'is swung t under it. The latch lever is a bell `crankfpivoted Qnthe v cylinder and'urged to inoperative outyvarqpositionbya coil spring 130. The lever is moved to operative position by a push solenoid 13f l which is actuatednnder control of the Work gauge which completes the solenoid circuit when the v vorkis nearly d own to size, as will later appear. The ratchet mechanism is later turned baclgwardlyor reset bya pawl 686 on an arm 690 actuatedgby aretracting cylinder unit '160. The pawl 6&6 -normallyfengages'a stop screw 152 adjustably mounted in aiixed lug 154.1

'I he Work contacting-[feder or forked gaugefG n is mounted for pivotalmovement (Figsy and 4) ing' spring which is seatedon a plate alc made Aline vv il ;h ag1 upper bearingsleeve on ra conical seat a slidablev sleeve f cap 422. The centering spring lets the gauge feeler float and center itself by contact with the work, the pivot studs being slidable axially in their bushings to a small extent.

The upper stud 418 is long enough to project through the upper bearing sleeve and has an arm 424 pinned thereto, the arm carrying a water seal 426 covering the upper bearing sleeve. The arm 424 projects upwardly and carries an adjusting screw 428 adapted to engage a hardened insert 438 in a shiftable actuating rod 432 which slides in guide bushings 434. On `the top of the work head is a dovetail base plate 346 (Fig. 2) supporting a slide 348 having a standard 349 to which a bracket 356 is adjustably attached by bolts 368 passing through a slot 353. The bracket supports dressing mechanism (not shown and of no immediate interest) but its suppcrtingbasev plate 346 is bored to receive and hold the above mentioned `guide bushings 434. The rod 432Y is urged in one direction by aicoiled spring 438 and its innerend carries a fork 440 loosely embracing a head 442 on a plunger projecting from a gauge support or indicator box 444 adjustably mounted by a-bracket 446on the work head. Y As will later appear', the spring yieldably causes resetting of certain movable gauge contacts in :the indicator box when the work sizing feeler or fork gauge Gris moved out of engagement with the work, the spring then causing the fork 440 to pull the headed plunger outwardly to the right in Fig. 5. Hardened inserts are inserted between the head 442 and the fork 448 to transmit movement in the opposite direction from the rod 432 to the headed plunger during gauging.

The feeler G straddles the work and its two diamond feeler points are normally urged substantially parallel to the work axis and substantiallyllengthwise of the tapered work surface 2 being 'ground in order to promote sensitivity. The feeler is urged against the work by a coiled spring 448 interposed between a nut 458 and a slidalble flanged bushing 452 which bears against a bifurcated actuating arm 454 attached to the pivoted gauge bar 486. The nut and the bushing are supported on a threaded stud 456 threaded in the end of a. piston rod 458 and forming an extension thereof. The stud has an abutment or head 468 normally spaced from but adapted to engage the outer surface of the bifurcated-arm 454 when the piston rod is pulled into its cylinder 462. This movement retracts the feeler from the work and controls the resetting of the gauge parts in the indicator box. "/When new work is inserted in the chuck,i a needle valve indicated in the diagram causes the piston rod 458 to delay the return of the feeler until the surface has been ground well down towards the desired size. Y

The headed plunger 442 slides in a boss 464 on the indicatorpbox and the end of it engages the actuating arm of a bell crank lever 466 pivoted on a pivot screw 488 and carrying a plate in the form of a cylinder 418vwhich engages the stem 4'12 of a visual indicator 414. The bell crank lever is urged in one'direction by a coil spring 416 to cause its actuating arm to engage the inner end of theheaded plunger 442. A pair of releasable contact making yor sizing levers 418 are pivoted on an eccentric shaft 488 which is angularly adjusted bya knob 482 and clamped by a nut 484. Eachflever carries a contact screw 486 adapted to engage a l contact screw 488 on the box to complete an electric circuit. VA coil spring 498 urges eachleverin a direction to engage its hardened .to be slightly shorter than the other.

insert 492 with the cylinder or arresting plate 418 and eventually to snap the lever to circuit completing position under control of the cylinder or arresting plate 41'8 which moves very slowly upwardly as the work changes in size. One lever is arranged to snap past the cylinder before the other, the two levers each having a slit and a wedging screw 494 so that one can be adjusted As will appear, the first circuit to be completed energizes aisolenoid which reduces the feed of a grinding wheel ratchet mechanism from coarse to ne and the other energizes a solenoid to stop a pawl feeding motor.- When the work feeler or gauge G is withdrawn from the work, the sizing levers 418 are reset by the headed plunger 442 which is pivoted loosely byra pin to a resetting lever 496 having hooks 498 tol engage behind bent pins 588 on the sizing levers.

Referring to Figs. 8 and 9 showing the electrical and hydraulic circuits and assuming a work piece has been carried to the ,chuck by the loader, the cylinder unit 544 causes retreat of the loader and starts the grinding cycle by closing a normally open switch 552. l This energizes a coil 198 thereby closing'a two-pole switch 889 which'causes a coil 882 to reverse a main reversing valve 884 supplied with pressure fluid from a pump886. Pressure fluid is directed through a pipe 888 to a series of cylinders. Cylinder 626 causes the grind-y ing Wheel to have a preliminary quick advance ready for the ratchet operated coarse feed. Cyl--4 inder 1131)Y moves the retracting ratchet pawl in the idle direction ready to cause feed retraction when grinding is done. The gauge shifting cylinder462 shifts the feeler towards the work but this movement is rendered slow by a needle or throttle valve 818 and a ball check valve 812 which communicate with vthe pressure line or pipe 888 so that contact of thefeelerlwith the workis postponed until 'the work hasreceived consider-'- able grinding, thus IeSSening-wear. The ball check valveby-passes the fluid only whenfthe fluid afterwards exhausts Ato th'e'pipe 888. l

As the main wheel slide is thus rapidly shifted forwardly by the cylinder 626, a contact screw 658 closes a normally open switch 652 thereby energizing acoil 814 which closes a normally open three-pole switch 816 and starts a pawl actuating motor 818 having a cam 828 which repeatedly reciprocates the plunger of avalve B22 piped to a pilot valve 824 which causes repeated reciprocaticn of the piston rod in the pawl feeding cylinder '122. Thus the feed pawl first imparts coarse feeding strokes as determined by the'stop screw 124 of Fig. `l.A As rgrinding proceeds, the feeler gaugecontrols the release of the iirst sizing lever in the indicator box and va'circut'i's completed,

by the corresponding contact screws 486P and 488 to thereby close a normally' open switch 826. This causes the solenoid 134 to be energized to swing the latch lever 128 and reduce the stroke ofthe pawl.

As the workv reaches cuit and actuates a double acting switch 828 one anerevel'seibenlein valvet' .Thus the' pipe-f v iinal'size, the feeler,v gaugefcontrols the completion of? the secondrgauge cirline 8Mtmecomesiannexhaust ilineasoithat' cylinder f unit, Mitretractsrlthe maintwheelfslideewhile 2 cyl'- ind'eruniti 6% quicklyiretractsvthe;ffeeler fgau'ge: andsresetsi-the cmovahles-gauge fcontacts'e and :the 1 retractingi cylinderil Gili resets Cthe .ratchetfmechanism-readyy-forea new feeds: Atwabout the :esame time coil 835 reverses.farifourewayzfvalveMailand;

the.k .chucking cylinder-f1 lioperates'toirelease `the Werlisa;

As the cylinderaunitzsthus:retracts .theiwheel','l

transmitting movement fr'omvthe' feelerif tqfthgsiz'i: ing-member. I Y- Inl` a `machine :of ithe vcharacter :indicated-fad work head; "a tol1head,i.apower. fun-iti connected? to -a sourceof fiuid-'flpressureforbringing'the toolafi andftheiworkinto machining fcontact'fa-workien gaging-:feeleig:y an actuating 1 armrforl moving tl1 -4 feelergcialspring flo'r-:urgingfthe:fe'elergt'owardsthei" work; a'=pis'tony rod-'for- 'operatingithe armi, a cyl-i Al0 Linder.v having-piping 'connect-ionslltoi:thei same energizefausolenoids 85El:andttherebyrreverse the. valve 844 so that the chucking cylindercauses the y new-fapiece:A to Ibeiclampedg thef.` operation fof .the

chucking cylinder? then :closingathef switch"` I I toenergizera solenoidef'iand reverse the valve: 848 7l toi retract Vthe r: loader. vwhich."'starts'the .-newfgrind-i on the machih'eitogrind a conicalshoulder'ontheworkyetheiwheerbeingadvancedrby.affeed: cylinder 2 6.0 and-ibeingffafterwards Adressedfunder control` of a, cylinderzdfandta valve'iif.v This dressing can A be :made ft'o14 occur at'everynycle` by. keeping closeda `switch? 85de Th'en Iasthe cylinder :Zllifvvhich is connected nto" the' main vvalve Srcauses a-.switch 262`1't0-frcloseg.' -a coil s220feffects compensation: -for' wheel wear and dressingzwhilefafsolenoidL856ire--- verses a valve 858 to operate the dressing cylinder 364.. Thelatter lrstLclosesf-aswtch 311 to energize a coil 860 for cooling water and later closes a switch 311A to energize a coil 852 to thereby make the valve 853 return the dresser.

I claim:

1. In a machine of the ,character indicated, a work head, a grinding wheel, the work head and the grinding wheel being mounted for relative movement of approach, a work engaging ieeler, a spring urging the feeler towards the work, a piston and cylinder unit for rapidly moving the feeler to retract the feeler from the work, a throttle valve for slowing the movement of the piston in the other direction to postpone the contact of the feeler with the work, and means for bringing the work and the grinding wheel into contact prior to contact of the feeler with the work.

2. In a machine of the character indicated, a Work engaging feeler, an actuating arm for moving the feeler, a spring for urging the 'feeler towards the work, a piston rod having an abutment normally spaced from the arm, the piston rod supporting the spring at one side of the arm and supporting the abutment on the other side, a cylinder for moving the piston rod to carry the abutment against the arm to render the spring ineiective and retract the feeler from the work, a sizing member, and means for transmitting movement of the feeler to the sizing member to determine the size of the work.

3. In a machine of the character indicated, a work engaging feeler, an actuating arm for moving the feeler, a spring for urging the feeler towards the work, a piston rod passing through the spring and extending from one side of the arm to the other, the piston rod having a head normally spaced from the arm on the side opposite to the spring, a cylinder for moving the piston rod to bring the head into or out of contact with the arm, a sizing member, and means for source of fluid pressure as thatof'th'e'powernnitii andthrottling-means in one of the'connect-ionsi to the @cylinder toprevent contactfof t'h'efeele'r withl' the: workfuntil the kpower runitl has dfirst "operated andisubstantialvmachining-has occurredy 5. Inf a machinefof'l ithe" character )indicated'gY a i work .head `for support-ing a work piece; a tool-'head -i having-a.maoliiningf` tool to engage-the wo'rk piece;'=a workl contacting --feele'r toicontrollthe-siz of the -ivor-kgf means `forbringing-th'e-worki andthieffltool-into AkmachiningJv contact; andlvmechanism'efore moving the feeler towards theworkgla contr`olli-'n'g-x devicev for starting-1saidfmeans-and-fsaid tmechanismgand a retarding device-in saidf-mec'man'ismuntilthe work and the tool-.have -beenin machin-l ing.contactfor a substantialpor-tion ofthe `-:rna-'-- chiningcperiod;V

6.` In: amachinef-of-the characterindicated-a* workh'ead for-supportinglaworkpiece, atoo'lfhe'ad having a machining-tool to engagethe-workpiece; means for -bringing the-tool fand '-the-work"-'into" machining I contact, a work# contactingl` feelrrto* controlthe sizefofithe-workl a piston-'rod having *connection-with theffeeler-acylinder having pipi;

ing connections for fluid pressure, a piston in the cylinder and connected to the piston rod, throttling means in one of the piping connections to postpone contact of the feeler with the work until the tool and the work have rst been brought into contact and substantial machining has occurred, and means controlled by said feeler when the work reaches size for causing the cylinder to retract the feeler from the work.

'7. In a machine of the character indicated, a gauge support, a movable contact making member movably mounted on the support, a plate for arresting and releasing the member, a lever movably supporting the plate and having an actuating arm, a plunger slidable in the gauge support and engaging the arm, a work engaging feeler, and means for transmitting gauging movement from the feeler to the plunger.

8. In a machine of the character indicated, va gauge support, a movable contact making member movably mounted on the support, a plate for arresting and releasing the member, a plunger slidable in the gauge support for actuating the plate to release the contact making member, a coil spring for moving the plunger in one direction, and a work engaging feeler for controlling movement of the plunger in the other direction.

9. In a machine of the character indicated, a gauge support, a movable contact making member movably mounted on the support, a plate for arresting and releasing the member, a plunger slidable in the gauge support for actuating the plate to release the contact making member, a resetting member connected to the plunger and having means to move the contact making member to arrested position, a work engaging feeler, and means for transmitting gauging movement from the feeler to the plunger.

10. In a machine of the character indicated, a

gauge support, a movable contact makingjmember movably mounted on the support, ,a plate for arrestingand releasing themember, a plunger slidable in the gauge support for vactuating :the plate to release the contact making member, a removablyrmounted onthe support, a plate for arresting and releasing the member, a plunger ,slidable in the gauge support for actuating the plate to release the contact making member, a work Aengaging feeler, and a member for controlling transmission ofl movement from the feeler to the plungensaid last-mentioned parts having a connection comprising a head on the one and an embracing fork on the other.

12. In a machine of the character indicated, a gauge support, a movable contact making member movably mounted on the support, a plate for arresting and releasing the member, a plunger slidable in the gauge support for actuating the plate to release the contact making member, a shiftable member for operating the plunger, a Work engaging feeler for transmitting gauging movement to the plunger, the plunger and the shiftable member having a connection comprising a head onrthe one and a fork on the other.

13. In a machine of the character indicated, a gauge support, amovable contact making member movably mounted on the support, a plate for arresting and releasing the member, a plunger slidablel in the gauge support for actuating the plate to release the contact making member, and a resetting member connected to the plunger and having means to restore the contact making member to arrested position.

14. `In a machine ofv the character indicated, a gauge support, a movable contact making member movably mounted on the support, a plate for arresting and releasing the member, a lever movably supporting the plate and having an actuating arm, a plunger engaging the arm, a sliding rodv connected to the plunger, a Work Aengaging feeler for sliding the rod in one direction, and a resetting lever connected to the plunger and having means to move the contact making member to arrested position. f

15. In a machine of the character indicated, a

Work head, a gauge bar having a pivotal mounting, agfeeler gauge secured to the bar and adapted to rengage the work, an actuating arm secured to the gauge bar, the pivotal mounting comprising axially movable Divot studs on the gauge bar and a centering spring urging the studs axially.

16. In a machine of the character indicated, a Work head, a gauge bar, a feeler gauge secured to the bar and adapted to engage the Work,` an actuating arm secured to the bar, pivot studs projecting from the gauge bar, bearings slidably and rotatably receiving the studs, one of the studs having a supporting ball at its end, and a spring exerting pressure on the ball.

RAYMOND H. CRAMER.