US2377982A - Grinding machine and method of grinding - Google Patents

Description

. June' 12, 1 945.` l I F. J. THELER' Erm. 2,377,982

' f -GRAINDING MACHINE AD METHOD GRINDIIINGy Filed Das. 24," '1942 4 .sheets-sheet 1 June l2, A1945. F. J. THELER ETAL GRINDING MACHINE AND METHOD oF-GRINDING Filed Dec. 24. i942 #sheets-sheet 2 l s. mmm@ N E WJ.. l T WD L im cab v E. 1 Y B QN u i. h kN Q5 1 n .EM Q N K NNN hv o ,Q a

June 12 1945 4 F. J. THELER ETAL 2,377,982

' 'GRlND'ING MACHINE AND METHOD oF GRINDING Filed Dec. 24,` 1942 4 sheets-sheet s VJacob Decke @lfb/W1;

INV o `Freoerick 15% er George W zlnns JAN MINN

GNN

Thur S.

WM.. am NWSU WHIIIIIIL mm. Qms, ONM, A mu. bm, v .l@ r/MW v A o 6-6 of Figure 3;

` Patented-.June l2, 1945 UNITED STATES PATENT oFFtcE f GINDING MACHINE AND METHODl F n GBINDING Frederick J. Thiele, George w. mans, and Jacob' l' Decker, Cincinnati, Ohio, assignors to The Cincinnati Milling l a corporation oi.' Ohio Application December 24, 1942, Serial No. 470,314

Q26 claims. (ci. n n) This vinvention relates to grinding machines and a method oi' grinding. One ofthe objects of this invention is to provide a simple, thoroughly practical and durable grinding machine -for accurately and economically grinding balls. Another object is to provide a construction of the above character which is well adapted to withstand continuous hard use and which employs the centerless grinding principle. Another object is; to provide a practical ball grinding attachment which may be applied to standard centerless grinding machines. Another object is to provide an economical and eilicient method of accurately grinding balls in a v centerless grinding machine. Other objects will be in part obvious and in part pointed out hereinvafter.

The invention accordingly consists inthe features of construction, combinations of elements, arrangements of parts, and in the several steps `and relation andA order of each of theA same toV one or more of the others, all as will be illustratively described herein, andthe scope of the application of which will be indicated in the following\claims.

In the accompanying drawings in which i's shown one of the various possible embodiments of this invention,

Figure 1 is an elevational view of the'machine;

Figure 2 is-a vertical sectional view taken on the line 2-2 'of Figure 1, certain parts of the machine being removed `for purposes of clarity;

Figure 3 is an-enlarged view of the left-hand portion of Figure 2,'certain of the parts thereof being broken .away for purposes of clarity;

Figure 4 is a vertical sectional view taken on une' 4,-: of Figure 3;

Figure 5 is a `vertical section taken on the line 5-5 of Figure 3;

I Figure 6 is a vertical section taken on the line Figure 'l Ais a horizontal section taken on the line 'If-1 of Figure 3 showing the pilot valve tripping mechanism; Figure 8 is a diagrammaticview of'the hyy draulic control support;

u opposed surfaces of the wheels. Grindingwheel I2 is rotated at 'high speed in a clockwise direcs Machine Co. Cincinnati, Ohio,

Similar reference characters refer to-similar partslthroughout the several views o! the drawings. i v

Referring now to Figure 1,1 the rnachinein-f I cludes a bed Ill having a regulating wheel II and grinding wheel I2 mounted thereon. On the right-hand portion of the machine bed, as viewed in Figure 1, surface ways I3 (Figure 2) support a carriage Il which is thus movable longitudinally of the bed; carriage I4 supports the regus lating wheel II and associated mechanism. A

bracket I6 secured to the right-hand portion of f tionI as indicated by the arrowln Figure i', and

effects a stock removal from the work` in the machine. The regulating wheel I I, which rotates at a relatively` slow speed in the direction of the arrow in Figure l, controls the rate of rotation 'through the grinding throat formed between the I of the'worlr in the machine. Thus, in operation, the parallel opposed faces of the wheels travel in opposite directions and form a grinding throattherebetweenI in which the work is placed.

Referring now to Figures l, 2, and 3, an attachment, generally indicated at 2l, is provided for supporting and acting upon the work as it passes regulating and grinding wheels. In generalI this attachment includes a framework supporting a workv rest blade generally indicated at 22.(.Figures r2, 4, and 6), aV reciprocating shuttle plate generally indicated at 23 (Figures 2, 4, and 5) which f to ' and driving mechanism for the shuttle plate generally indicated at 24. The work is iedv into the Figure 9 is a vertical sectional view, on an:

enlarged scale, of thatl portion'lof. Figure 2 where workiis ejected iromthe grindingthroat of the machine;A

yFigure "10 is a vertical sectional view taken on the line. III-lu of Figure 9; and,

lFigure 11 is a vertical sectional view taken on the line`I I-'II of Figure 3.

moves transversely oi the faces of the wheels.

grinding throat adjacent the left-hand edge` of the grinding wheel, as viewed in-Figure 2, and is moved across plate from left to right, .duringwhich time the work is acted upon by the shuttle plate, 'grinding wheel, and regulating Wheel. all as will be fully described hereinafter.4

The framework of the attachment includes a the grinding throat by the shuttle' grinding 'and regulating wheels.(Figures 1 and 2) and is secured to slide |4 (Figure 2) by screws 25.

Screws 26 extend through slots in bed plate '25 extending longitudinally of the machine and thread into carriage |4. Thus, the attachment may be adjusted toward and from the regulating wheel. The vertical supports 21 and 28 extend upwardly from and are secured to bed plate 25 adjacent the ends thereof and support transverse plate 29 above and parallel to bed plate 25. The rear face of bed plate 25, as viewed in Figures 2 and 4, has a cut-out portion 30 within which work rest blade 22 is positioned. 'I'his blade is secured in a vertical position to the bed plate by Y a series of bolts 3| which extend through vertical slots, such as slot 32 (Figures 3 and 4), in the Work restblade, pass through holes in the bed plate of substantially the saine diameter as the shank of the bolts, and thread into nuts 33(Fig ures 2 and 4). 'I'he slots are also of substantially greater width than the diameter of the shank of the bolts 3| (Figure 3), thus permitting adjustment of the work rest blade both vertically and longitudinally with respect to'the bed plate 25. Elevating screws, such as screw34 (Figures 3 and 4), are provided to permit accurate vertical adjustment of the work rest blade tobe made, and longitudinal adjusting screws, such as screw 35 (Figures 3 and 4), are provided for making accurate longitudinal adjustments oi the work rest blade with respect to the bed plate. Longitudinal screw 35 (Figure 3) acts against a boss 38 formed on a vertical support 31' secured tothe rear face of bed plate 25. Thus, the work rest blade is accurately adjustable both vertically and longitudinally and, when so adjusted, is clamped in place by boltsl.

.The upper portion 33 of the work rest blade-22 (Figures 4 and 6) is tapered to conform to the shape of the grinding wheels, and the upper edge 39 of the blade 22 extends transversely across the faces of the grinding and regulating wheels (Fig ure 2) parallel to the grinding throat -formed therebetween. The upper edge 39 (Figures 4 and 6) of the work rest blade is beveled toward the regulating wheel thus insuring rotation of the balls by the regulating wheel. The beveled edge 39 oi' the work rest blade extends a substantial distance to the left of the grinding and regulating wheels (Figures 2 and 3) which are of substantially the same width.

Shuttle plate 23 is mounted on four rollers 40. 4|, 42, and 43 which are positioned in the same plane as work rest blade 22 (Figures '4 and 5). As the mounting'of rollers 42 and 43 upon the bed plate is substantialy similar, detailed description of these rollers will be limited to the mounting of roller` 42. As best shown in Figures 3 and 5, a bracket 44 is secured by bolts 45 to the rear face of bed plate 25. Bolts 45 extend through vertical slots 45 in bracket 44 and thread into bed plate 25. Thus, the position. of bracket 44 with respect to bed plate 25 may be adjusted vertically. A shaft 41 (Figure 5) is mounted in the upper' portion of bracket 44, and roller 42 is As the mounting of rollers 40 and 4| (Figure 2) upon vertical supports 21 and 23 is substantially similar, detailed description of the mounting of these rollers lwill be limited to the mounting of roller 40.1 Referring to Figure 3, an arm 4B is pivotally mounted at 49 on vertical support 21. A'shaft 50 (Figures 3 and 5) is mounted in the right-hand end of arm 48, as viewed in Figure 3, and is held thereby by a bolt Roller 40 is revolubly mounted on shaft 50 above roller 42. A projection 52 (Figure 3) extends outwardly ,from the end of arm 48 and is connected by a spring 53 to a bolt 54. Bolt 54 extends through and is adjustably connected to a bracket 55 (Figures 3 and 5) secured to the rear face of bed plate 25. Spring 53 resiliently urges arm 43 downwardly and, by adjusting nuts 58, the tension on spring 53, and thus the force acting downvwardly upon arm 48, may be increased or derevolubly mounted upon thisr shaft. Thus, rollers 42 and 43 may be adjusted verticaly with respect to the bedplate (Figure 2) permitting vertical creased.

Referring to Figure 3, an elevating screw 51 threads through a boss 53 on vertical support 2l and acts. upon a lug 5l formed on the rear tace oi arm 48. Arm (Figure 2) oi roller 4| is acted upon by an elevating screw similar to screw 51, and thus these rollers may be moved upwardly by their respective elevating screws to permit removal of the shuttle plate. Thus rollers 4U and di are resiliently urged downwardly against the upper edges of the shuttle plate and act as effective guides during movement of the blade, and the shuttle plate may be conveniently removed from the attachment.

As is best shown in Figures 2 and 5, the upper and lower edges 8|, 82, 83, and 54 of shuttle plate 23 adjacent the endsthereof are preferably bev-l lbrackets upon which rollers 42 and 43 are mounted and an efficient mounting oi' the shuttleplate is achieved through the action of the resilient springs urging rollers 40 and 4| downwardly.

As best shown in Figures 2 and 3, the lower edge of the shuttle plate 22 has a cut-out portion 65 therein into which the beveled edge 33 o! the work rest blade extends. Referring to Figures 2 and 6, retainer blades 33, 51, and 83 are mounted on the lower edge of the cut-out portion of shuttle plate 23 and are held in position thereon by a clamping plate 42 and bolts 1l. 'I'he lower edges of blades 55, 31, and 53 are positioned parallel and in alignment'with the beveled edge 39 of the work rest blade. A small wire 1| (Figure 6) is positioned between the upper edges of the retainer blades and shuttle plateA 23 and may be changed to a wire oi' different size for accurately locating the retainer blades 'ver' tically with respect to the balls. This permits the blades to be adjusted for balls of ditierent sizes. The retainer blades are preferably positioned just tar enough above the balls sothat the u l blades do not touch the balls but will prevent them from jumping out of, or piling up in, the grinding throat during operation of the shuttle plate,

'I'he balls 12 are reciprocated in the grinding throat by actuating pins 13 (Figure 3) and 14 (Figure 2). Actuating pin 13 is mounted in a support 15 which is secured to shuttle plate 23 by -screws 19. This pin, which is in alignment with the centers of the balls in the grinding throat, is threaded through a downwardly projecting portion a of support 15, and by turning its head 19, which is positioned in a cut-out 'portion 19 of shuttle plate 23, the actuating end 13a of pin 13 may be adjusted with respect to the shuttle plate.

Pin 1I (Figure 2), which extends through a hole 99 in the lower part of the right-hand portion of the shuttle plate, threads through an end plate 9|. This pin is also in alignment with the centers of the balls in the grinding throat, and its position may be adjusted by turning its head 32. Pins 13 and 1I serve to move the line of balls positioned along the edge 39 of the work rest blade to the right and l'eft, as viewed in Figure 2, as shuttle plate 23 reciprocates, all as will be fully described hereinafter.

The portion of the beveled edge 39 of the work rest blade, which extends to the left of the grinding and regulating wheels as viewed in .Figures 2 and 3, is enclosed by a pair of plates 493 and 84 (Figures 2 and 4) ,secured to the work rest blade 22 by bolts 86 and 81; the plates extend above the beveled edge `39 of blade 22 (Figure 4) thus to enclose the left-hand end of the train of balls, as viewed in Figure 2.

As best shown in Figures 2,' 3, and 4, a work. feeding tube 88 extends upwardly labove the framework of the attachment and is mounted upon transverse plate 29 in any suitable manner. The lower end ofthe tube is aligned with a passageway 89 extending through a block 99. Block 99, which extends downwardly into a cut away portion of shuttle plate 23,is mountedby screws `225 (Figure 4) on a vertical support 31 (Figure 3) connected to bed plate 25.l As is best `shown in Figure 3, bolts 31a and 31h secure vertical support 31 to the rear face of bed plate 25 and extend through horizontal slots 299 and 29| in vertical support 31. Thus,the position of vertical support 31 and block 99 may be adjusted longitudinally with respect to bed plate 25 and shuttle plate 23.

Thelower portion of block 99 has a channel 9| (Figures 3 and 1l) therein which extends lengthwise across the block. This channel is closed to the left of passageway 89, as viewed in Figure 3, by a block 93 which is secured to block 99by screw 99. The right-hand end of block 93 with the side walls of channel 9| forms -a con- V tinuation of the work feeding passageway 89 in block 99. A cut-off blade 95 (Figures 3 and l1) is slidably mounted for longitudinal movement with respect to block 99 in the right-hand section of channel 9|, as viewed in Figure 3. This blade has a pin `99 (Figures 2 and 3) which extends outwardly through an elongated slot 91 (Figure 2) in the side wall of channel 9|. This pin is connected to a second pin 93 set in block' 99 by a. spring 99 which acts through pin 99 to resiliently urge the cut-ofi blade 95 (Figure 3) to the left, as viewed in this figure. The cut-off blade 95.is

also provided with a threaded extension |99 thereon upon which a stop member |9| is mounted for purposes to be disclosed more fully hereinafter.

Immediately below block 99l a feed plate, generally indicated at |92, is mounted in a eut-oui-l portion of shuttle plate 23, The upper surface of thisplate retains cut-oft blade 95 within channel 9| (Figures 2 and 3), as viewed in Figure 3, coacts with stop member |9| to situate the cut-o1! blade. As pointed out and its right-hand end |92a,

' The balls accordingly move hereinabove, shuttle plate 23 moves with a reciprocatlng action, and when the shuttle plate is positioned at the right-hand end of its stroke, as viewed in Figures 2 and 3, the string of balls in tube 88 and block 99 rests on the upper flat sur- .face |93 of plate |92. To the right o f surface |93 a passageway |94 slants downwardly through feed plate |92 and connects with a passageway |95 extending through shuttle plate 23 and support 15 (Figures 3 and 11),.

In operation, as shuttle plate 23 moves to the left as viewed in Figure 3, movement of feed plate ,|92 permits spring' 99 (Figure 2) tomove the cutoff blade 95 in the same direction. The V-shaped nose |99 of therblade extends between the two lower balls in'tle string of balls resting on sur face |93. This separates the lowermost ball from in the shuttle plate. An adjustable stop |91 is provided threading inte the right-hand end scf block 99 which limits the movement of the cutoff blade to the left, as viewedin Figure 3.

When the shuttle plate moves to the right, as viewed in Figure 3, and is approaching the end. of its stroke in that direction, the end portion |920 of feed plate |92' strikes stop member |9| and thus carries the nose of cut-oil' blade 95 from the path of the balls feeding through block 99. downwardly, the lowermost ball'strikingthe at surface |93 of feed plate |92. On the return movement of the shuttle plate, the lowermost ball is again cut off from the stringand fed into the grinding throat. As is best shown in Figures 2 and 9, the end of actuating pin 14 moves a slightly greater distance than thewidth of one ball beyond the beveled edge 39 of the work rest blade 22 when the shuttle plate 23 is at the end of its stroke to the right, as viewed in Figure 2. The ball which moves over the end of edge 39 falls downwardly between plates |98 and |99 (Figures 9 and l0) and enters a passageway ||9 (Figure 2) in block secured to the rear face of bed plate 25. The balls passing from the end of passageway ||9 drop into a trough IIZ-by which they leave-the machine. A resilient iinger H3 (Figures 9 and 10) is mounted on bolt III, and its upper end is positioned imrneclial'elt1 above the end of beveled edge 39 (Fig-l ure 9) of the work rest blade. This ilnger engages the upper portions of the balls yas they reach the end of the grinding throat and prevents more than one ball from leaving the grinding throat each time the shuttle moves to the right. as viewed in Figure 3,-all as will be described hereinafter.

' In operation, each time the shuttle plate moves to the right, as viewed in Figure 2, the balls in the grinding throat are moved by actuating pin 13 against the end of actuating pin 14, and at the end of the stroke in this direction, the ball which has been pressed beyond finger ||3 falls of! the edge of the work rest blade and leaves the machine, nger ||3 holding the remainder of the balls on beveled edge 39. At this time, the end 13a of actuating pin 13 is positioned adjacent the left edge of passageway |93 as viewed in Figure 3'.

As the plate moves to the left as viewed in F18- ure 3, there is a lost motion period before the end of actuating pin 1I strikes the ball retained by'nzer m in the grinding throat, and as pin 13 is moving to the right during this lost motion period, a space is provided at the left-hand end of the train of balls on the edge o1' the work rest blade. During this same movement a ball is cut ofi' from the string of balls in block 30 and falls down into passageway |05 into this space. Thus, as the shuttle plate moves to the right, as viewed in Flgure 2, a ball leaves the grinding throat, and as the'shuttle moves to the left, a ball is added to the right-hand end of the train of balls passing therethrough. An opening ||8 (Figures 3- and 11) is provided in the rear of passageway |05. 'Ihis opening permits balls to escape from the shuttle plate, should they start to pile up therein due to failure of the feeding process.

The hydraulic mechanism 24 (Figure 2) is mounted on the framework of the attachment by supports 22| and 222 which are secured to the bed plate and transverse plate 23, respectively.v Shuttle plate 23 (Figure 3) is driven by a piston rod |2| which is connected to piston |20 of hydraulic mechanism 24. This rod is connected to the shuttle plate by a swivel joint |22 and is connected to piston |20 by nut |23. 'I'he reciprocating. movement of piston |20, in its cylinder |24 is controlled by the hydraulic control system diagrammatically shown in Figure 8. A pilot valve, generally indicated at |21, which controls a reversing valve, generally indicated at |28 (Figure 3), which in turn controls piston i 20, is mechanically operated by shuttle plate 23.

Referring to Figure 7, a shifter rod |29 extends through a hole in vertical support 21. This rod is prevented from rotating within the support by a set screw |30( and has adjustable shoulders 3| and 32 secured to its opposite ends. It will be noted that the end of set screw |30 engages a slot in shifter rod |29, thus permitting movement of the shifter rod transversely of vertical support 21. Shoulder |3| engages a. slot |33 in the end of the stem |34 of pilot valve |21 and shoulder |32 extends forwardly from rod |29 and is positioned in the -path of the end plate |26 of shuttle plate 23. moves to the right, as viewed in Figures 3 and 7, end plate |26 strikes shoulder |32 and moves the pilot valve stem |34 'to the right through shifter rod |28 and shoulder 3|, thus changing the setting of the pilot valve. When the shuttle plate moves in thel opposite direction and approaches the end of its stroke, an adjustable stop |25 on end plate |28 strikes the end of the pilot valve stem, |34 andl moves it to the left to reverse the position of the pilot valve. Accordingly, movement of the shuttle plate to the left or right, as viewed in Figures 2 and 3, controls the movement of the pilot valve,and as the shuttle plate approaches the end of its stroke in either direction, the pilot valve is shifted to reverse the action.

Referring now to Figure l, a casing, generally indicated at |35, is shown which contains a pump, a relief control valve, and a sump. From this casing, pressure and sump conduits |36 and |31, respectively, enter a stop control valve |38. A pair of flexible conduits |39 and |40 connect stop control valve |38 with hydraulic control mechanism 24.

As best shown in Figure 8, a pump |4| pumps the hydraulic fluid from sump |42 to stop control valve |38 through conduit |36. In conduit |36 between pump 4| and stop control valve |38 a relief valve |43 is provided to insure a constant pressure. When stop control valve |33 is in its Thus, as the shuttle plate on" position, as indicated by the dotted lines |44, conduit |38 is connected to pressure conduit |39. This conduit enters the center portion of both pilot Valve |21 and reversing valve |28. Sump conduit |31, which connects stop control valve |38 to the sump, at this time is connected to sump conduit which'in turn is connected to ports |45 and |46 of pilot valve |21 and ports |41 and |48 of reversing valve |28. A pair of conduits |43 and |50 connect reversing valve |28 to the cylinder within which piston |20 is positioned, and a pair of conduits |5| and |52 connect pilot valve |21 to reversing valve |28. In conduits |5| and |52 are check valves |53 and |54 which permit the hydraulic fluid to flow from the pilot valve |21 to the reversing valve |28 but prevent flow in the opposite direction. 4These check valves are by-passed by choke coils |55 and |56 for purposes to be disclosed more fully herelnafter.

In operation, when piston |20 has moved shuttle plate 23 to the right, as viewed in Figure 2, its end plate |28 (Figure 7) moves the pilot valve stem |34 to the right to the position shown in Figure 8. It will be noted that the pilot valve |21 has an enlarged central spool |51 which provides a pressure differential and makes the valve selfactuating after the spool passes the center pressure port |58.

After the pilot valve has been moved to the right into the position shown in Figure 8 by end plate |26 (Figure 7), pressure from conduit |38 entering the pilot valve through port |58 leaves this valve through conduit |5|, passes check.l valve |53, and enters port |10 of the reversing valve. The pressure fluid entering this port moves the reversing valve to the light to the position shown in Figure 8. Hammering of this valve against the end of the cylinder housing is prevented by choke coil |53 which delays the flow of the pressure iluid from the opposite end of the cylinder. The fluid leaving' this valve passes through conduit |52 to pilot valve |21 and thence to the sump through port |46 and sump conduit |40.

When the reversing valve is in the position shown in Figure 8, pressure fluid entering reversing valve |28 through port |60 passes out through port |13 of the reversing valve into conduit |48. As this conduit enters the right-hand end of the cylinder enclosing piston |20, piston |20 and shuttle plate 23 move to the left, as viewed in Figure 2.

As the shuttle plate approaches the end of its stroke to the left, as viewed in Figure 2, adjustable stop |25 (Figures 3 and 7) engages the end of pilot valve stem |34. This moves the spool |51 (Figure 8) of the pilot valve to the left of pressure port |58. This places pressure port |58 in communication with conduit |52 which causes the pressure fluid to move the reversing valve |28 to the left, as viewed in Figure 8; This places pressure port |60 in communication with conduit |50 which causes the pressure fluid to enter the right-hand end of piston cylinder |24, thus causing piston |20 to move the shuttle plate to the right, as viewedin Figure 2.

Thus, shuttle plate 23 is moved with a reciprocating action by the hydraulic mechanism generally indicated at 24, and this movement is dlrectly controlled by the shuttle plate through the tripping mechanism shown in Figure 7. The rate of reciprocation of the shuttle plate may be controlled by regulating the pressure of the fluid in the hydraulic system through pressure relief valve I adjusting the position of shoulders |3| and |32 on shifter rod |29. Preferably the advancing movement of the balls is equivalent to approxi- 4mately the circumference of a ball during the movement of the shuttle plate to the right, as viewed in Figure 2.. This gives each ball one complete revolution during the movement of the shuttle plate in this direction. As a ball leaves .the train of balls supported by the work rest blade at the end of this stroke, and as there is a 'lost Thus, the several objects mentioned hereinabove, as well as many others, are successfully and practically accomplished by the method and apparatus disclosed hereinabove. a

As many possible embodiments may be made ofthe mechanical features of the above invention, and as the art herein described might be.

varied in various parts, all without departing from the scope of the invention, it is to be understood that all matter hereinabove set forth, or y shown inthe accompanying drawings, is tol be interpreted as illustrative and not in a limiting sense.

We claim:

l. In apparatus of the nature described, in combination, a grinding wheel and a regulating wheel forming a grinding throat, work rest means for supporting a, train of balls in said grinding throat, and means for moving said balls with a reciprocating movement transverse to the faces motion period between the time the end of actuating pin 14 engages the ball at the right-hand edge of the work rest blade on thev return stroke of theshuttle, the return movement of the balls' is equal to approximately two-thirds of their circumference, although the strokes of the shuttle plate in either direction are equal. vAccordingly, the train of balls advances approximately the diameter of one ball for each reciprocation of the shuttle plate. The actual movement of the shuttle plate is preferably slightly greater than the` amounts given hereinabove because sufficient lost motion must be introduced to compensate for eccentricities in the balls in the train on the-work rest blade.

In operation, balls are fed into the feeding tube 88 (Figures 2 and 3) andare fed into the train of balls onV the work rest blade one at a time as described hereinabove. This is controlled by the reciprocation of the shuttle plate. During each.

reciprocation a ball is ejected from the train as described hereinabove. As` the balls pass through v the grinding throat, the regulating wheel (Fig ure l) rotates the balls, and the grinding wheel .removes stock from them as irregularities or excess metal of the balls are presented. In'theV removal oi' stock the grinding wheel tends at any i given instant to cut along the line of a great circle,

but the simultaneous rotation about another axis continually changes the direction of the great circle along which the cutting takes place. Thus the total effect on the balls. as they' are passed through the'throat rotated by the shuttle results in a true sphere whose surface is completely defined by the continuous cutting along lines at a constant radius from the center of the sphere. Metal is never removed below the exact diameter of the sphere, for that diameter is determined by l the distance from the grinding surface to the coacting point 'on the regulating wheel. In llike manner, the metal in no direction and atV 'no point exceeds this precise diameter, for such metal is ground away by the cutting actionv which has been brought to bear upon every point on the for rotating a train of balls in the grinding throat of said wheels as said -balls move through said grinding throat.

2. In` apparatus of the nature described, in combination, a grinding wheel, a regulating' wheel formed between the grinding and regulating Wheels in a direction toward the grinding wheel, means for supporting said balls in said grinding throat, and reciprocating shuttle means for ro- 0 tating said balls in directions transverse to the direction of rotation of said |wheels as said balls pass through said grinding throat.

3. In apparatus pcf-the nature described, in combination, a grinding wheel, a regulating wheel 5 for rotating a train of balls in the grinding throat formed between the grinding and regulating v vlwheels in a direction toward the grinding wheel, means for supporting said balls in said grinding throat in substantially a straight line withreto spect to each other, means other than said Wheels for causing the rotation of said balls in a direction transverse to the direction of rotation of said wheels vduring the grinding of said lrballs in said grinding throat, and means toprevent said 5 balls from moving upwardly out of said grinding throat as they move therethrough.

4. In apparatus of the nature described, in combination. a grinding wheel, a regulating wheel for rotating a train of iballs in the grinding throat 0 formed between the grinding and regulating wheels in a direction toward the grinding wheel, means for supporting said balls in said grinding throat, reciprocating actuating means for rotating said balls in directions `transverse to the d irec- -through said grinding throat, and means to pre-I surface of the sphere during the travel of the n balls through the throat of the machine.

It will thus be seen that a thoroughly eflicient and practical method and apparatus for grinding balls. on a centerless grinding machinehas been a disclosed. The apparatus is in the formof an attachment which may be installed on standard centerless grinding machines having flat wheels. This results .in a material saving of abrasive material, more efficient operation; and b alls which-are accurately ground. A

vent said balls from moving upwardly out of said grinding throat as they move therethrough.

-5. Invapparatus of the nature described, in combination, a grinding wheel and a regulating wheel forming a grinding throat therebetween, said grinding and regulating wheels having straight operative faces,A work rest means having a substantially straight work supporting edge, means for feeding balls onto said work rest means adjacent one edge'of said grinding wheel, means for removing balls from said work rest means adjacent the other edge of said grinding. wheel, and actuating means f or moving said balls through said grinding throat and causing them to rotate transversely to the direction of rotation imparted to said balls by said regulating wheel during ythe actual grinding of said ballsin said throat.

6. In apparatus` of the nature described, in

tion of rotation of said wheels as said balls pass combination, a grinding wheel and a regulating wheel forming a grinding throat therebetween, work rest means, means for feeding balls onto said work rest means adjacent one edge of said grinding wheel, means for removing balls from said work rest means adjacent the other edge of said grinding wheel, actuating means for moving said balls through said grinding throat and f or causing them to rotate transversely to the direction of rotation of said wheels, and retainer means positioned above said work rest means for preventing the balls from moving upwardly out 01' 'the grinding throat.

7. In apparatus of the nature described, in combination, a grinding wheel and a regulating wheel forming a grinding throat therebetween, work rest means, means for feeding balls onto said work rest means adjacent one edge of said grinding wheel, means for removing balls from said work rest means adjacent the other edge of said grinding wheel, actuating means .for moving said balls through said ygrinding throat and for causing them to rotate transversely to the direction of rotation or" said wheels, and retainer means positioned above said work rest meam for preventing the ballsfrom moving upwardly out of the grinding throat, said retainer means and said work rest means being adjustable toward and from each other.

8. In apparatus of the nature described, in combination, a grinding wheel and a regulating wheel forming a grinding throat therebetween, work rest means, means :for feeding balls onto said work rest means adjacent one edge of said grinding wheel, means for removing balls from said work rest means adjacent the other edge of said grinding wheel, reciprocating actuating means for causing said balls to rotate in directions to the right and left of the direction of rotation imparted to said balls by said regulating wheel, and means for causing the movement of said balls through said grinding throat.

9. In apparatus of the nature described, in

means transverse to the direction of rotation of said wheels, and retaining means positioned above said train of balls to prevent movement of said balls upwardly out of the grinding throat.

12. In apparatus of the nature described, in combination, a grinding wheel and a regulating wheel having a grinding throat formed therebetween, means for supporting a train of balls in said grinding throat, `a shuttle plate, means for moving said shuttle plate with a reciprocating action, means on said shuttle plate for acting against the ends of the train' of balls positioned in said grinding throat, whereby said balls are rotated in both directions by said actuating means transverse to the direction of rotation of said wheels, and retaining means positioned above said train of balls to prevent movement of said balls upwardly out of the grinding throat, said work supporting means and said retaining means being adjustable toward and from each other. whereby the position of said balls in said grinding throat may be varied to accommodate balls of dii-ferent sizes.

13. In apparatus of the nature described, in combination, a grinding wheel, a regulating wheel for rotating a ball positioned in the grinding throat formed between the grinding and regulating wheels, said ball being rotated by said regulating wheel in a direction toward said grinding wheel, and reciprocating shuttle means acting upon said ball to rotate said ball in directions transverse to the direction of rotation of said y wheels.

combination, a grinding wheel and a regulating wheel forming a grinding throat therebetween,

a, work rest blade positioned .transversely of the face of said grinding wheel and adapted to support a train of balls in said grinding throat, a reciprocating shuttle adapted to move transversely of the face of said grinding and regulating wheels, yand means on said shuttle for cans-- .ing said balls to rotate in directions transverse tothe direction of rotation of said wheels.

10. In apparatus'of the nature described, in combination, a'grindingwheelrfand a regulating wheel having a grinding throat formed therebetween, means for supporting a trainof balls in said grinding throat, a shuttle plate, means for moving said shuttle plate with a reciprocating action; and means on said shuttle plate for acting against the ends of the train of balls positioned in said grinding throat, whereby said balls are rotated in both directions by said actuating means transverseto the direction of rotation of said wheels.`

11. In apparatus of the nature described.`in-

combination, a grinding wheel and a regulating wheel having'a grinding throat formed therebetween, means forqsupporting a train of balls in s aid grinding throat, a shuttle plate, means for .moving -said shuttle plate with a lreciprocating action,`means on said shuttle'plate rfor acting.

against A,the ends of the train of balls positioned Ain saidgrinding throat,'-'whereby said balls are rotated in both directions by said actuating als 14. In apparatus of the nature described, in combination, a grinding wheel and a regulating wheel forming a grinding throat therebetween, work rest means for supporting balls in said grinding throat, means for feeding said balls into said grinding throat, means to permit removal of said balls from said grinding throat, and reciprocating means acting upon said balls in said grinding throat to move said balls in directions transverse to the faces of said wheels.

15. In apparatus of the nature described, in combination, a grinding wheel and a regulating wheel forming a grinding throat therebetween, work rest means for supporting a train of balls in said grinding throat, means-for feeding said balls into said grinding throat, means to permit removal of said balls from said grinding throat, and oscillating means acting upon the ends of said train of balls in said grinding throat to move said train of balls with a reciprocating movement transverse to the faces of said-wheels.

16. In apparatus of the nature described, in`

in said vgrinding throat, reciprocating means, and

means on said reciprocating means acting on the ends of said train of balls on said work rest means to oscillate said train of balls transversely with respect to the faces o1' said wheels.

17. In apparatus of the nature described, in combination, a grinding wheel and a regulating wheel forming .a grinding throat therebetween,

' work rest means for supporting a train oi' balls l means to prevent said balls from moving upwardly in said grinding throat, reciprocating means,

means on said reciprocating means acting on the ends of said train oi" balls on said work rest means `to oscillate-said trainof balls transversely with respect to the faces of said wheels, and

out of said grinding throat during the oscillation of said train of balls.

18. In apparatus ofthe nature described, in

combination, a grinding wheel and a regulating wheel forming a 'grinding throat therebetween, work rest means for supporting a train of balls in said grinding throat, reciprocating shuttle ,means for moving said train of balls in directions transverse to the faces of said wheels, hydraulic means for driving said shuttle means, and tripping mechanism operated by said shuttle means for controlling the direction of movement and length of stroke of said hydraulic driving means.

l 19. In apparatus of the nature described, in combination, a grinding wheel and a regulating Vwheel forming a grinding throat therebetween,

work' rest means for supporting a train of balls in ysaid grinding throat, reciprocating shuttle means for moving said train of balls in directions transverse in the faces of saidwheels, means controlled by movement of said shuttle means for feeding balls'to said train of balls, and means controlled by said shuttle means for removing balls from said train ci balls.

v20. In apparatus of the nature described, in

combination, a grinding wheel and a regulating wheel forming 'a `grinding throat therebetween,

` fworlr vrest means for supporting a train of balls in said grinding throat, reciprocating shuttle means for'moving said train of balls in directions transverse to the faces of said wheels,

'means controlled by movement of said shuttle means forfeeding balls to said train of balls,

means controlled by said shuttle means for removing balls from said train of balls, and `means on said shuttle means for retaining said balls in said grinding throat.

21. I'he herein described art which includes the steps of, supporting a plurality of balls, grinding said balls in the general direction of the means by which saidv balls are supported, applying a rotating force to said balls in substantially the opposite direction on sides substantially opposite to the sides being ground, and

f moving said balls during said grinding with a reciprocating action transverse to the direction 22. In apparatus of the nature described, in combination, a grinding wheel and a regulating wheel having a grinding throat therebetween,

' said grinding wheel and said regulating wheel 23. In apparatus'of the nature described, in combination. a grinding wheel and a regulating wheel having a grinding throat therebetween,

said grinding wheel and saidregulating wheel,

having `substantially straight operative faces, means for supporting a ,train of balls in said' grinding throat in a substantially straight line as said balls are being ground in said grinding throat.

24. In apparatusof the nature described, in combination, a grinding wheel and a regulating wheel forming a grinding throat, said grinding wheel and regulating wheel being adjustable toward and fromeach other, work rest means for supporting a train of balls in said grinding throat, said work rest means being adjustable upwardly and downwardly in said grinding throat, and means for moving said balls with a reciprocating movement transverse to the faces of said wheels as said balls pass through said grinding throat.

25. 'I'he herein described art which vincludes the steps of, supporting a4 train of ballsvin a grinding throat formed between a grinding wheel and a regulating wheel, grindingv said balls in the general direction of the means by which said balls are supported, said regulating wheel rotating said balls to move their surfaces adjacent the grinding wheel in substantially the same direc'- tion as .the 'adjacent` surface of the grinding wheel, and moving said train of balls during grinding' in directions transverse to the direction of rotation of saidwheels with a reciprocating action and with an excess of forward move- ,Y

ment to successively move said balls through and out of said grinding throat.

26. The herein described art which includes thevsteps of, supporting aplurality of balls in a grinding throat formed between a grinding Wheel and a regulating wheel, grinding said balls in.

moving said balls with a reciprocating action transverse to the faces oi said wheels.

FREDERICK J. THELER. GEORGE W. BINNS. JACOB DECm.

Images