US2363128A

US2363128A - Grinding machine

Info

Publication number: US2363128A
Application number: US409499A
Authority: US
Inventors: Heffelfinger Robert Daniel
Original assignee: Hamilton Watch Co
Current assignee: Hamilton Watch Co
Priority date: 1941-09-04
Filing date: 1941-09-04
Publication date: 1944-11-21
Anticipated expiration: 1961-11-21

Description

9 4- R. D. H EFFEL FINGER 2,363,123

GRINDING MACHINE 7 Filed Sept. 4, 1941 s Sheets-Sheet 1 4 my 44 I INVENTOR.

. I Robz'rful-lzFFa Fingar F1911 ATTORNEYS.

V Nov. 21, 1944.

R. D. HEFF ELFINGER GRINDING MACHINE Filed Sept. 4, 1941 3 Sheets-Sheet 2 Robmf D. HFFI Finger ATTORNEYS.

Nov. 21, 1944. R. D. HEFFELFINGER 2,353,128

\ (:RINDING MACHINE 3 Sheets-Sheet 5 Filed Sept. 4', 1941 2 mm w INVENTOR RoberT HzFFol Fing BY ATTORNEYS.

A only has been shownby way I invention;

- wheel oscillat Patented Nov. 21, E944 GRINDING MACHINE Robert Daniel Heflelflnger, ltead l igila assignor H to Hamilton Watch Company, Lancaster, Pat

Application September 4,1941,1ser1e1No.4oa49cfl r 11 Claims. (eta-5 4s This invention relates to grinding machines and has for an object the provision of improved means and method of grinding. V Anoth' r object is to provide means and metho of grinding jewels to a high degree of accuracy. Another object is to provide a jewel grinding machine of the centerless grinder type in which the grinding wheel is adapted to be oscillated along its own axis.

Another object is to provide a Jewel grindin machine of the centerless grinder type having improved jewel supporting means.

Another object is to provide a jewel grinding machine of the centerless grinder type, having accurate and micrometrically measurable adjustment and action. 1

Another object is to provide a grindingmachine having means adapted to resurtacepthe grinding wheel to a micrometrically controlled depth and means adapted to advance the object to be ground a 'micrometrically controlled amount in accord Another object is to zprovide'a jewel grinding machine adapted to interchangeably mount a holder for rough grinding and a holder for fine grinding. 1

wFlg. .VIIIis a partial enlargement of Fig.VI, showing the regulating rollersupport; a

i Fig. IX is a partial front elevation of Fig.*VII, showing the support for solid workpieces;

Fig. X is a front elevation similar to Fig. IX, showing the support ioridrllled workpieces;

Fig. XI is a partial right end elevation 'of the structureoiFig.X; 11.91. .1 1: i l

Fig. XIIis a detail of thewirehodling portion oithestructureoiFig'.x; and :1 i Fig. XIIIisadetail of the wire tightening portion of the structureot Flgtx. w v

i This. inventionrelates to improved. means and method orgrinding thexperipheries of objects to circular. contoursiand/orgrinding the peripheries inconcentricity withglven centers in the objects. The deviceiandmethod ofthis invention may be utilized. forthelgrinding of any type of ob- J'ect desiring aperipheral grinding and may readance with the depth of the resurfacing of the Other objects and advantages of the invention will become apparent iron; the tollowingdescrip tion taken in connection with the accompanying drawings. It will be apparentthatmany changes may be made in the details of. construction, ar rangement of pa ts; and method shown and de-' scribed without departing hem the spiritof the invention as expressed in ,tlie accompanying claims;

1,; therefore, o. not wish to limited to the exact details of construction, arrangement H of parts and methodfshown, astheprei'erifed form ily beused to grindtoqan approximation or to veryclosetolerancesr t H r. r i :In the formationgofiobiects expensive to purchase and/or process, for instance watch jewels. it is desirable inworderltormeetthe exacting requirements of modern :watchmaking to form the periphery as 'a circle which, in the case. of solid jewels, needs to be iormedwith as littlewaste oi Jewel material'aspossible, andin thecase of drilled Jewels, accurately. "concentric with the drilled hole. In the; past, soliddewels have. been ground withoutjthe careiul regard to minimum stock loss that shouldbe exercised and drilled jewels. have been-ground without careful regard ery withthe drilled holes to the achievement ot-concentricity of. thelperiph- This invention.provides means and method of permitting the peripheral grinding oi objects such .as solid watc'h' Jewels, to accurate, circular contours withapminimuln ct waste material and of Fi II can dilemma madame of the structure otFlglI;illustratingthe grinding objects such as drllledwatcntiewels not onlv with w s mater a u o to a a curateconcentricity with. the d 'llledhole. A f. Ingeneral, it utilizesa grinder of the centerless with nieansrfor supporting the Jewels {in position against the grinding Wheel in addition to the holding action of theregulating roller, with me ns n-tosefl at nsa 89m n whee on its wares an 5 b t 1 inanimate ns adjustment andoperation. ll-l maritimema omet proper .grinding position, the shafts 2 and l are substantially parallel, and the peripheries of the grinding wheel I and regulatingroller 3 roll on or closely adjacent each other.

The grinding wheel I is driven through the 5 pulley 5, and the regulating roller 3 through either pulley 6 or pulley 1, depending on the speed desired, and both are preferably rotated in a clockwise direction from the left end elevation view 10 as shown in Fig. VI.

Thus, as illustrated in Fig.1II, the peripheries of the grinding wheel I and regulating roller 3 pass each other going in different directions.

These directions may be reversed if desired, but

one should be opposite the other at the passing point in order to cause the workpiece, which is a watch jewels in this inst: rice, and mounted between the grinding wheel I and the regulating roller 3, and held from i alow by supporting plate 9, to rotate so as to be uniformly and properly abraded.

Watch jewels, in the stage of their manufacture at which the processof peripheral grinding is used, are substantially flat discs and the operation desired is, in the case of an undrilled jewel, 2

to grind the disc into a peripherally circular shape, and in the case of the drilled jewel, :not

only into a circular shape but also with th periphery concentric with the drilled hole.

The work involved in grinding the peripheries of such jewels is extremely delicate. Approximate dimensions for a jewel may be 15 thousandths of an inch in thickness, 30 thousandths in diameter, and when drilled, the hole may be 5 thousandths in diameter.' In order to meet the rigid present chine is used, with the solid jewels held between the grinding wheel I and the guide roller 3 by the pressure of the guide roller 2 on them, a

supporting plate 9 beneath them, and the action of a spring pressed pin ill (see Fig. IX) on the jewels in end to end relation and against an upright I I on the supporting plate 9. Drilled jewels are held in grinding position as illustrated in Fig. x. I In addition to the customary pressure of the regulating roller 2, they are strung on a wire II and held inend to end relation by end pressures of the wire holders, and also supported from beneath by a plate l2, similar in function and form to plate 9 of Fig. IX.

The machine .of this invention is so made as to permit interchange of jewel holding assemblies. When solid jewels are being ground, or a rough port of the jewels being ground and an effective method of grinding.

It is preferable to grind the jewels in a group, with the jewels laid end to end across the face of the grinding wheel, which is oscillated on its own axis so as to utilize the entire lateral extent of the periphery of the wheel'in grinding the jewels,

and to wear the wheel down with relative uniformity throughout.

The jewels may be ground singly or in small groups if desired, but it is'easier to achieve the great accuracy demanded by using enough jewels, end to end, to approach the dimension of the width of the periphery of the grinding wheel. The jewels are grouped in end to end relation and held together by a suitable adhesive such as water repelling grease, so that they form, in effect, a single long substantially cylindrical object which is much more amenable to accurate processing than a singlejewel or smaller group would be.

The first step in grinding the jewels is to make certain that the grinding wheel presents a uniform peripheral surface. This is done by operating the grinding wheel dresser. The dresser comprises a threaded shaft l3 which is mounted in brackets l4 and IS in parallelism with the axis shaft 2 of the grinding wheel- I. The shaft I3 is" rotatable in its mounting but is fixed against longitudinal movement.

An extension I6 of bracket 15 supports a handle I! which is so connected to the shaft I3 adjacent its support in bracket II that turning of the handie I! rotates the threaded shaft l3.

The dressing tool I8 is carried across the peripheral face of the grinding wheel I by a rider block l9. This block is internally threaded and mountedon shaft I3. The block I9 is held against rotation about and is free to travel along the shaft l3 so that rotation of the shaft. l3 through turnin of the handle I], causes the rider block l9 to move along the shaft I3 and carry the tool l8 across the face'of the grinding wheel I.

The rider block I9 is mounted on a support Isa which is in dovetail sliding arrangement with a rigid support 20 so that the movement of the tool l8 across the grinding wheel is firm and regular.

The depth to which the grinding wheel is dressed may be regulated within close limits through the use of the micrometer screw 2|. Screw'2l is connected to the dressing tool l8 and is adapted to move the tool toward or away from the periphery of the grinding wheel in a direction 7 normal to the direction of movement of the.rider block I! along the shaft IS. The tool I8 is held? rigidly in the position of depth to which it has been moved by the locking action of lock member 22 on the micrometer screw 2|.

The above described micrometer measurement of the depth of the grindingwheel dressing action grind on a drilled jewel is being carried'out, the so is an important feature of this invention since it assembly of Fig. 1x is used, and when the drilled jewel is being fine ground to bring its periphery to concentricity with it hole, the assembly of Fig.

" 'xis' used.

Movements of the regulating roller and the o5 jewel holders with respect to the grinding wheel,

' as well as the adjustment of the grinding wheel dresser, are made micrometrically in this device and this contributes largelyto the close tolerances within which this machine may operate.

The objects of this invention have been accomplished'by providing the several parts of the machine with variety and delicacy of movement and adjustment, with the movements and adjustments porting shaft 2 is mounted in bearings 23 and 24 a and so formed and mounted as to be slidable in cooperatively functioning to provide uniquev sup- 76 the

bearings

23 and 24 along its longitudinal axis,

thus permittinglateral movement or oscillation of the grindingwheel I.

The arrangement of automatic means for oscillating the grinding wheel is illustrated in Fig. II. The wheel supporting shaft 2, mounted in bearmounted thereon and it is through the action of ing 23, has a peripherally recessed collar pin member 26 mounted on cam lever 21 and exand the shaft 2 is moved back and forth along its own longitudinal axis.

When the grinding wheel is being dressed, it is necessary to stop its oscillation so that the dressing maybe accurate and accomplished without unnecessary danger of breaking the dressing tool. A locking member 32 is provided for this purpose. It is pivoted at 33 and movable about that pivot through the use of its handle 34 so as to contact the cam lever 21 and push it away from the cam against the action of the spring 3|.

The cam 30 is driven through a train of gears from the grinding wheel shaft 2. This train consists of a gear 35 mounted on the shaft 2, an intermediate gear 36, a worm gear 31 and the cam gear 38. This gear train is so formed as to oscillate the grinding wheel out, of step with its rotation so as to achieve maximum distribution of the wear on the grinding wheel.

The supporting unit for the regulatin roller 3 is shown in assembly in Fig. IV and enlarged in Fig. VIII. In Fig. IV it is shown as the unit at the left of the machine. In order to provide adjustment of the roller 3 laterally of the grinding wheel periphery, the unit is mounted for lateral adjustment on the base plate 39. An intermediate plate has a T slot 4| in which a headed holding bolt 42 is positioned. A camming lock bolt 63 is mounted in the base 39 and is designed to draw the bolt 42 downward and lock the intermediate plate 80 to the base 39 with the roller 3 in adjusted lateral position alongthe track 44.

The entire regulating roller unit is readily removable from the machine through the connection of the locking bolt 42 between the base plate 39 and the intermediate plate 40.

The axis t of the regulating roller 3 must be parallel to the axis 2 of the grinding wheel i and the peripheral grinding surface thereof in order to grind the jewels to equal diameters. It is the function .of the wheel dresser to produce parallelism between thegrinding wheel axis and periphery; Accordingly the regulating roller unit is pivoted about a vertical pivot 45 located toone side oi the regulating roller 8, so that the roller may be bodily moved in a horizontal arc'toward and away from the grinding wheel, and its axis 4 brought into parallelism with the axis 2 of the grinding wheel I. i

The pivot 45 extendsthrough the pivot plate I and is secured in. the intermediate plate 40. Theintermediate plate ll is provided with a horizontallyextendingslot 41,- through which, extends a lock bolt 48, secured to the pivot plate ll. The

lock bolt u is loosened topermit the regulating roller unit to be moved about its vertical pivot I, and thereafter is tightened in its arcuately adjusted position.

The regulating roller 3 is movable away from the grinding wheel I in a straight line horizontal movement in order to facilitate the loading or unloading of the jewels, and to make the rinding portion of the machine accessible.

The straight line horizontal movement of the to hold the unit regulating roller with respect to the grinding wheel is provided for by the arrangement of the sliding plate 49 which is mounted in a dovetail track on the pivot plate 46, and the movement is accomplishedthrough the manual operation of the handle 50.

The slide plate 49 is micrometrically adjustable on the pivot plate 46 through the action of adjustment screw 51 and indicator finger 58. The inner end of the adjustment screw 51 butts against the pivot plate 46 to limit the movement of the slide table 43 towards the grinding wheel.

The adjustment screw 51 is locked in adjusted position by the lock nut 59.

Movement of the handle downward will move the regulating roller 3 away from the grind.. ing wheel I since the handle 50 is pivoted on the sliding plate 49 at 5| and pivotally Joined with a link 52 which ispivoted at 53 to the pivot plate 46.

That part of the supporting structure of the regulating roller unit which is immediately adjacent and supporting the regulating roller 3 is mounted on a horizontal pivot 54 which is bracketed to the slide plate I! and parallel to the axis 4 of the regulating roller. Consequently the regulating roller 3 is movable about pivot 54 toward and away from the grinding wheel I. The bracket support of the pivot 5| has a stop shoulder 55 which a stop pin 56 mounted in the pivoted regulating roller support is adapted to abut to limit the movement of the regulating roller toward the grinding wheel about the pivot I.

The regulating roller 3 is constantly urged toward the grinding wheel I by a weight 6 0 (Figf VI). The weight 60 operates through a flexible connector 6241 of rope or other suitable material, connected to the regulating roller unit at 82 above the pivot 54. Consequently the weight 80 holds the stop pin '56 against the shoulder 55 and the adjustment screw 5'! against the outer end. or the pivot plate 48. 1

The regulating roller 3 preferably has an outer surface in the form of a sleeve of cushioning ma, terial such as rubber, to permit the rotation of irregular jewels between the grinding wheel and the regulating roller. Minor irregularities are taken up by the irregularities sinking into the outer cushion of the regulating roller. More pronounced irregularities cause the regulating roller to be bodily moved about the pivot 54, while extreme irregularities would cause the regulating roller to be moved about the pivot 54 until stopped by the micrometrically adjustable screw 6|, after which the motion would transfer to the slide table 40 and any further motion away from the grindingwheel would be rectilinear. The screw II is bracketed to the slide plate I! and its threaded end is adapted to contact the regulating roller supporting structure which 'is pivoted about the pivot 54. The limit of the movement oi the regulating roller 8 about the pivot ll away from the grinding wheel may,'

therefore, be set micrometrically by regulation of the adjustment screw ll which is locked in adjusted position by a lock nut "a. In this manner a limit may beset to the relatively easy movement of the regulating roller 3 away from the grinding wheel I about the pivot 54. a When this limit has been reached, a. greater load is imposed upon further movement away from the grinding wheel by making it necessary to move the slide table 46 in addition. Both the pivoted and sliding movements are under the influence oi the weight 60. The arrangement of the cushioning surface of the regulating roller for minor jewel contour irregularities, movement about the pivot 54 for without the necessity of the movement of the slide table 49.

The regulating roller 3 is also adjustable vertically with respect to the grinding wheel. This is accomplished through the sliding relation of the immediate support of the regulating roller with that portion of the unit which is pivoted at 54. The vertical movement is carried out by manipulation of the micrometer adjustment screw 84. The screw 64 is bracketed to the immediate support of the regulating roller and threaded into that part of the unit which is pivoted at 54.

A spring member 65 acts to urge the regulating roller shaft 4 upwardly to take up for whatever slack may be introduced by irregularities in the thread of the adjustment screw 64. The regulating roller is locked in its vertically adjusted position by a lock member 88 which draws the immediate support of the roller against that part of the unit which is pivoted at 54.

All of the adjustments and movements described above in connection with the regulating roller provide for very accurate placement of the regulating roller 3 with'respect to the grinding wheel Land the jewels 8. These accurate and fine movements and adjustments contribute largely to the achievement of the hitherto unobtainable accuracy and close tolerance processing of jewels which are the results of this invention.

The jewels dealt with particularly are rubies of the type used in watches. a 1

The jewel supporting structures shown in Figs. IX and X are interchangeable and used separately. Figs. IX and VII show one structure and Figs. X and XI show another. v They are both mountable on the general structure as shown in Fig. IV as the unit at the right of the machine, although the unit there shown is the unit of Fig. IX.

Both of these structures are adjustably and removably secured to the base plate 39 by means .of a T slot and headed bolt as shown at 6'! and 88 respectively in -Fig. V, in just the same manner and for the same purposes as the slot 4i and bolt 42 described in connection with the structure of Fig. VIII;

They also have an intermediate plate 69 and and peripheral grinding edge of the grindin wheel.

The jewel supporting structure which is adapt ed to support solid jewels both for rough and line grinding. and drilled jewels for rough grinding, is illustrated in Figs. VII and xx.

The operation of the slide tables 14 of the jewel supporting units differs from the operation of the slide table 48 of the regulating roller supporting unit in that the tables 14 are not constantly urged toward the grinding wheel but are adjusted to the desired position and then locked in place. In Fig. VII this is accomplished by the lock member 16, and in Fig. XI by the lock bolt 14a. The screw I5 may be locked in adjusted position by lock 11. Consequently the jewels are positioned against the grinding wheel by adjustment and then rolled thereagainstunder pressure by the regulating roller 3 and in accordance with the rotation thereof.

The jewel support of Fig. VII is pivoted about a horizontal pivot III which in position of operation extends in a direction normal to that of the axis 2 of the grinding wheel I. This arrangement permits aligned group of jewels which are to lie between the pin Ill and abutment Illa (Fig. IX) to be adjusted with respect to levelness so as to make possible the desired grinding action throughout the jewel group. In order to achieve uniform grinding action throughout, the jewel group must be level'and parallel to the axis and periphery of the grinding wheel. w

The pivot 18 is threaded into the vertical pivot plate I9 and extends as a pivot through the upright 80 which is fixedto the horizontal slide plate I4. A look bolt 8|- operable in conjunction with the pivot 18 is also threaded in the vertical pivot plate 19 and movable horizontally in a slot 82, about the pivot 18 as a center, in the fixed tical slide plate 84 mounted in a dovetail 'slide in pivot plate It. Support plate 9 and the auxiliary slide plate 85 which holds the jewel plunger 83 are both mounted on slide plate 04 and consea, pivot plate 10 with a pivot II, adjustment slot and screw 12 and I3 and a slide plate 14 with micrometer screw Ii, similar to the structures described in connection with Fig. VIII. The jewel supports are accordingly laterally adjustable, re- I assembly of jewels in parallelism with the axis the desired position between the grinding wheel and regulating roller.

FigJIX illustrates the relative positional relation of the jewel support plate I and the jewel plunger 83. The plunger 08 is movable vertically with respect to the support plate I and is also so pivoted about horizontal pivot 08 as to'permit arcuate adjustment of the plunger 83 with respect to the support'plate l.

The vertical movement orthe plunger; is accomplished by adjustment of the auxiliary slide plate 85 with respect to the slide plate 84, in a recess of which it is mounted. This is done by releasing the locking screw ti and moving plate 45 within the limits 01' its adjustment slot 92, under the heads of the shoulder screws 89 and I0, and the purpose of the adjustment is to per i arcuate adjustment is to provide means for centering the pin I8 with the jewels and with the upper edge of the support plate 9.

The jewel plunger 83 is slldable within and longitudinally of the sleeve 94 and when in operation, urges the pin I8 against the jewels under the action of spring 96 mounted within the sleeve 94. The action of spring 98 may be strengthened or weakenedas desired through adjustment screw 91 which is held against the end 98 of the sleeve 94 by the spring 98, and the pin I8 may be-held out of contact with the jewels when desired by positioningpin 99, which is secured to plunger 83, in retaining slot I88 formed in'sleeve 94.

The jewe1 supporting structure which is particularly adapted to fine grinding of drilled jewel and which makes possible the forming of the jewel periphery to accurate concentricity with the jewel hole, is illustrated in Figs. X and XI.

The support plate I2 and the jewel wire II on which the jewels 8 are strung through their drilled holes, are secured to slide plate I M and movable vertically therewith. Slide plate IN is slidably mounted on pivot plate I9 and vertically adjustable through the action of micrometer screw 88. The slack oi! the thread of screw 88 is taken up by spring 88a and the slide plate IN is held in adjusted position by lock screw 81.

Fixture plate I82 supports the jewel support plate I2 and the wire II and provides their connection to the slide plate I8I through assembly bolt I83.

The fixture plate I82 has an upright I84 which vided with a handle I28, adapted, through a link arrangement like that of Fig. VIII, to move the unit horizontally toward or away from the grinding wheel. This arrangement may be used in this instance since the jewels are strung on wire II and will not fall when moved.

What I claim is:

1. In a grinding machine, a grinding wheel, a regulating roller adapted to rotate in cooperation with the grinding wheel, and a work support adapted to hold an object to be ground between the grinding wheel and the roller, said work sup-' port being mounted for pivotal movement with respect to said grinding wheel and said roller about a horizontal and a vertical pivot.

2. In a machine of the centerless grinder type, a grinding wheel, a regulating roller adapted to rotate in cooperation with the grinding wheel, a work support adapted to hold an object to be ground between the grinding wheel and the roller, and means for oscillating said grinding wheel along its own axis during the operation of said machine, said work support being mounted for pivotal movement with respect to said grinding wheel and said roller about a horizontal and a vertical pivot.

3. In a machine of the centerless grinder type, a grinding wheel, a regulating roller adapted to rotate in cooperation with the grinding wheel, a work support adapted to hold an object to be ground between the grinding wheel and the roller, and means for oscillating said grinding wheel along its own axis .during the operation of said machine, said roller being mounted for movement toward and away from said grinding wheel about a horizontal and a vertical pivot, and said work support being mounted for pivotal movement with respect to said grinding wheel and said roller about a horizontal and a vertical pivot.

4. In a grinding machine, a grinding wheel, a

regulating roller adapted to rotate in cooperation with the grinding wheel, and a work support supports the wire holding member I88 (see Fig.

XII) and an upright I88 which supports the wire tightening ,unit illustrated in Fig. XIII. The support plate I2 is adjustable with respect to the wire II through bolts I81 and openings I88 in the uprights I84 and I86.

The wire holder I85 (see Fig. XII) mounted in the upright I84 has an opening I89 through which the wire II is passed, and a slotted end H8 to which the wire is secured. The holder I85 is held in position by lock screw II I The wire drawing unit shown in Fig. XIII includes a bearing sleeve II2 mounted in upright I88 and adapted. to be locked therein by set screw II3.

The sleeve H2 has an opening II4 through which the wire II passed, and is externally threaded at IIII with an adjustment nut III threaded thereon. A smaller sleeve 1, also externally threaded and hollow, extends within the opening I I4 and an adjustment nut I I8 is threaded thereon to move the sleeve II'I within the opening 4., Sleeve II! has a slotted end H9 to ,which the wire II is secured.

The jewels 8 are threaded on the wire II, one end of which is secured to the member I88 and the otherto the sleeve 1. The nut H8 is so adjusted that the jewels are pressed end to end by wire holder I85 and sleeve I I2 and the lock screws III and 3 are set. Then the nut III is turned to draw the wire II tight, and the jewels are. ready for grinding.

The jewel holder unit of Figs. x and XI is proadapted to hold an object to be ground between the grinding wheel and the roller, said roller being mounted for movement toward and away from said grinding wheel about a horizontal and a vertical pivot, and for such micrometrically adjustable vertical straight line movement as will enable said roller to move in an arc, about said horizontal pivot, of greater or less radius in accordance with said vertical adjustment.

5. In a grinding machine, a grinding. wheel, a regulating roller adapted to rotate in cooperation with the. grinding wheel, and a work support unit adapted to hold an object to be ground between the grinding wheel and the roller, said unit being mounted for pivotal movement with respect to said grinding wheel and said roller about a horizontal and a vertical pivot, and for micrometrically adjustable vertical straight line movement and comprising a base plate and a work holder,

said holder being adjustable vertically and about a horizontal pivot independently of said base rotate in cooperation with the grinding wheel, a

work support comprising a base plate and a horizontally acting spring pressed finger and being adapted to hold an object to be ground between the grinding wheel and the roller through vertical support by said base plate and endwise horizontal support by said spring finger, and means for oscillating said grinding wheel along its own axis during the operation of said machine.

' 7. In a machine for grinding drilled objects, a grinding wheel, a regulatingroller adapted to rotate in cooperation with the grinding wheel, a work support comprising a base plate and a wire upon which said drilled objects are adapted to be threaded and held between the grinding wheel and the roller, means for applying tension endwise of said wire, and means for oscillating said grinding wheel along its own axis during the operation of said machine.

8. In a grinding machine of the centerless grinder type, a base, a grinding wheel mounted on said base, an intermediate plate mounted on said base for sliding adjustment transversely of the working face of said grinding wheel, a pivot plate mounted on said intermediate plate and for movement with respect thereto about a vertical pivot, a slide plate mounted on said pivot plate for micrometrically variable sliding adjustment toward and away from said grinding wheel, an upright mounted on said slide plate for movement with respect thereto about a horizontal pivot, a regulating roller support mounted on said upright for micrometrically variable vertical sliding adjustment with respect thereto, a regulating roller mounted on said roller support and adapted to rotate in cooperation with said grinding wheel, and a work support adapted to hold an object to be ground between said grinding wheel and said roller.

9. In a machine of the centerless grinder type,

a grinding wheel, a resilient regulating roller rotating oppositely to and in cooperation with said grinding wheel, a work supporting unit arranged between the wheel and the roller, means for adjusting the roller relative to the grinding wheel, and means for adjusting the supporting unit ver tically and about both a vertical and horizontal pivot.

10. In a machine of the centerless grinder type,

- a grinding wheel, a resilient regulating roller rotating oppositely and in cooperation with said grinding wheel, a jewel supporting unit arranged between said wheel and roller, jewels carried on said unit, and means for adjusting said supporting unit vertically and about a horizontaland vertical pivot to bring said jewels into contact with both grinding wheel and said resilient roller.-

11. In a machine of the centerless grinder type, a grinding wheel, a resilient regulating roller rotating oppositely and in cooperation with said grinding wheel, a jewel supporting unit arranged between said wheel and roller, jewels carried on said unit, means for adjusting said supporting unit vertically and about a horizontal and vertical pivot to bring said jewels into contact with both grinding wheel and resilient roller, and means for moving said grinding wheel-back and (forth along its axis to present divergent grinding paths to said jewels.

ROBERT DANIEL HEFFELFINGER.