US2398022A

US2398022A - Groove-finishing apparatus

Info

Publication number: US2398022A
Application number: US546176A
Authority: US
Inventors: Marren Thomas
Original assignee: Individual
Current assignee: Individual
Priority date: 1944-07-22
Filing date: 1944-07-22
Publication date: 1946-04-09
Anticipated expiration: 1963-04-09

Description

T. MARREN 2,398,022

GROOVE FINISHING MACHINE 5 shees-sheet 1 A A m Nm, O S .w N T i @Mmmm x .EW

April 9, 1946. T MARRE 2,398,022

GROOVE-FINISHING APPARATUS Filed July 22, 1944 5 sheets-sheet 2 a, 32 32 52 Z/a INVENTORv Thomsfrren BY l ,/7

ATTORNEYS April 9, 1946. vT` MARREN 2,398,022

GROOVE-FINI SHING APPARATUS Filed July 22, 1944 5 sheets-Sheet 3 l ATTORNEYS T/mm as M02 'rch' Apm 9, 19216.

T. MARREN GROOVE-FINISHING APPARATUS Filed'July 22, 1944 5 sheets-sheet 4 I Rg. /2

April 9, 1946. T, MARREN GROOVE-FINISHING APPARATUS Filed July 22, 1944 5 Sheets-.Sheet 5 y INVENTOR N /omzs Marre/7 JM/MW T ATTORNEYS Patented Apr. 9, 1946 UNITED STATES PATENT OFFICEA GROOVE-FINISI-IING APPARATUS Thomas Marren, Stamford, Conn.

Application July 22, 1944, Serial No. 546,176

(Cl. Eil-58) 23 Claims.

This invention relates to apparatus for finishing grooved surfaces of machine parts and the like, and more particularly to a machine for Precision grinding, lapping and polishing the tracks or grooves of production parts such as ball bearing races. v

In the manufacture of inner rings or races for ball bearing assemblies, it is common practice to turn each ring roughly to form, as on a screw machine or the like, after which the rings are hardened and ground except for the grooves, preparatory to finishing the critical surfaces of the latter.

The finishing oi the grooves is in many cases done partly by hand, the procedure being to mount a number of rings on a mandrel which may be rotated at high speed, and to apply a grinding or lapping stone to the grooves in the rings one at a time, holding the stone with a uniform pressure against the surface of the groove, and moving the stone so as to uniformly traverse and clean out the rough area. This method when done skillfully is usually precise enough for theV final lapping and polishing of the grooves but is slow and costly, and may not be used for the heavier grinding operations. For, if comparatively large amounts of stock were to be removed from the groove, as by a coarser grinding operation, the groove would become out-of-ground due to the impossibility of producing precise movements and pressures by hand on the grinding stones.

Efforts have been made heretofore to use machinery for grinding and polishing the groove in cach ring, but diiculties were encountered in maintaining the proper pressures and movements of the stones, and it was found that the grooves became egg-shaped as a result. Moreover, with the machinery employed, only one ring at a time was Worked on, and the time consumed in the operation was therefore still considerable and costly. l

It is an object of this invention to provide a groove-grinding and finishing machine which obviates the above difficulties.

This is accomplished by the provision of a mechanism for applying, with a predetermined oscillatory curvilinear motion, grinding or lapping means under uniform pressures to movably mounted workpieces, as for instance bearing rings, in a manner that the surfaces of the grooves thereof are uniformly finished.

In the form of this mechanism, illustrated herein as exemplary of the invention, a plurality of bearing rings to be finished are mounted on a mandrel which issupported at both ends and turned preferably at high speed. A plurality of holders are arranged in tandem to slidably carry finishing elements, the holders being individually pivotally mounted on a carriage having an operative position with respect tothe mandrel, so that the finishing elements of the holders may engage and transversely sweep the grooves in the rings along an arc having a center substantially coincidental with the lcenter of curvature of the grooves. The holders are interconnected, and automatically driven to oscillate about their pivots in unison, causing all the finishing elements simultaneously laterally to traverse along these predetermined arcs the grooved surfaces of the respectively engaged rings. Means are preferably provided for applying uniform individual pressures to the elements during their oscillating movements, and in the illustrated form of the invention this means is exemplified by a flat tubular inflatable member of rubber or other flexible material engaging force-transmitting links or couplings connected with the slidable finishing elements and so arranged that they may apply substantially equal and uniform working pressures to the latter.v These applied pressures cause all the elements to press uniformly and with equal force against the surfaces ofthey grooves, and this together with the arcuately correct travel of the working surfacesv of the elementsv controls uniformly the amount of material 'removed from the rings during the finishing operation. v

In the form shown the construction is such that, when the rings on the mandrel have been finished, the machine housing may be swung open on a parting line, together With a hinged cap on one of the bearing blocks for the mandrel, so that the latter may be quickly and conveniently lifted out and replaced by another mandrel having'unfinished rings previously arranged thereon. Thus high production is possible, due to the simultaneous finishing of all the rings on a mandrel in one operation, and the provision of means for quickly replacing mandrels.

By the above arrangement, the arcuate movements of the Working surfaces of the elements, and the equality and uniformity of the pressures of Same against all the rings simultaneously provide a high degree 0f accuracy in the finished grooves, so that few, if any, rings are rejected.

The machine housing has a second parting line to provide access to the finishing elements, the mountings for which permit quick replacement of broken or worn abrasive elements to be made. A Window in the housing permits observing the condition and setting of the elements during running of the machine, so that improperly finished workpieces may be held to a minimum.

By the provision of the iniiatable bag, constant easily controlled pressures are maintained at all times on the elements even when these wear away unevenly, since a considerable displacement of the bag at any one point is possible Without materially affecting adjacent portions.

The finishing elements carried by the holders may be sufiiciently coarse, and the iiuid pressure transmitted thereto suiiiciently great to enable coarse grinding of the grooves. Or, by changing to lesser pressures and finer abrasive elements, accurate lapping and polishing operations may be carried out.

Provision is made for adjusting the location of the axis of oscillation of the mounting means for the finishing elements, so that finishing operations on race grooves of either small or large radii, or small or large diameter bearing rings may be carried out.

The transmission of pressure from the iniiatable bag to the finishing elements is preferably carried out byV individual link assemblies, each comprising a slide and a pivoting arm. The construction is such that, when the finishing elements are oscillating, resulting small periodic increases in the pressure exerted by the bag are compensated by slight` diminutions of pressure due to the angularity of the pivoting arms. .As a result a substantially constant pressure is maintained at all times between the working surfaces of the finishing elements and the grooves of the workpieces.

A separable driving connection is provided between the pivotally mounted pressure transmitting arms and the finishing elements, and means are provided for aligning the arms when the housing is opened along the parting line provided to give access to the finishing elements, so that when the housing is again closed the matching parts of the arms and elements will be aligned for meshing.

Another feature of the invention is the provision of adjustable means for taking upwear in the mountings of the elements so that the positions of the latter may be accurately held at all times, providing `for uniform accuracy in the finishing f the rings.

In an illustrated modification, mounting means or holders are provided for carrying a plurality of elements to be applied to the individual bearing rings, thus minimizing the wearing of each element and also providing for a quicker finishing of the grooves thereof.

Other features and advantages will hereinafter appear.

In the accompanying drawings- Figure 1 is a longitudinal vertical sectional-V view through the machine of this invention.

Fig. 2 is a transverse vertical section taken on the line 2-2 of Fig. l. u

Fig. 3 is a part-plan, part-sectional view on line 3-3 of Fig. 1.

Fig. 4 is a front elevation of the machine.

Fig. 5 is a fragmentary right end elevation of the machine, showing the split bearing Vfor the mandrel.

Fig. 6 is a view similar to Fig. 5, but showing the upper half of the machine swung backward and the split bearing for the mandrel separated to permit removal of the latter.l

Fig. '1 is a left end elevation of the machine showing the upper half of the machine swung backward as in Fig. 6, for removing the mandrel carrying the bearing rings.

Fig. 8 is a transverse sectional view similar to Fig. 2, but partly in elevation and showing the upper portion of the machine housing swung backward to permit access to the finishing elements.

Fig. 9 is a fragmentary sectional view similar to Fig. 1, but showing the finishing elements and holders in inclined position.

Fig. 10 is a vview similar to Fig. 9, but showing the machine adjusted for finishing slightly larger sized bearing rings.

Fig. 11 is a view similar to Figs. 9 and 10, but showing the machine adjusted for finishing still larger sized bearing rings.

Fig. 12 is a sectional view showing a modified form of holder, carrying a pair of finishing elements.

As shown in Figs. 1 and `2, the machine embodying this invention comprises an elongate stationary Abase 20 which may be of cast iron or other suitable material, having front and rear walls 20a, a left end wall 20h and a right end wall 20c. Mounted within the

walls

20a, 20h and 20c of the base is an upstanding housing 2|, the front and rear walls 2| a of which extend respectively inside the walls 20a and the left end wall 2lb of which extends inside the end wall 20h. The right end wall 2|c of the housing is located directly over the end wall 20c of the base and substantially in alignment therewith.

The end wall 20h of the base has rotatably mounted therein a bushing 22 having a cylindrical recess 23 and square counterbore for receiving the square end 24a of a mandrel 24 carrying a plurality of bearing rings 25. The other end 24b of the mandrel is carried in a split bearing block 26 forming part of the end wall 20c of the base. As shown in Fig. l, the rings 25 are mounted with spacing collars 27 between them so that they are uniformly spaced on the mandrel, the latter being provided with threads and a nut 28 which when tightened secures the rings 25 and collars 21 tightly against a shoulder 29 on the mandrel.

The bushing 22 is provided with a. drive pulley 30 by means of which it may be rotated, togetherwith the mandrel 24 and bearing rings 25, through connection with a driving motor not shown.

According to the present invention a mechanism is provided within the housing 2| for mounting finishing elements so that they may be made to laterally sweep or traverse with a predetermined periodic motion and with uniform pressure the grooved surfaces of the bearing rings 25 for precisely finishing said surfaces.

As shown, a plurality of tubular holders 3| having angularly extending legs 3|a are mounted by means of the latter on pivot screws 32 threaded into the front and rear walls of the housing 2|. The holders 3| are individually connected to a driving link 33 so that they may be made to oscillate in unison. Each of the holders 3| slidably carries a sleeve 34, Fig. 2, in which is frictionally mounted a finishing element 35, the lower portions of the sleeves being split, as shown at 3|b, Fig. 8, and biased inwardly for this purpose. The elements 35 may be of abrasive stone or the like. The top ends of the sleeves 34 have rigidly attached thereto caps 36 by means of which pressure is applied to the finishing elements 35.

By the provision of the pivotally mounted holders 3|, the finishing elements 35 may be caused to pivot aboutV a point which exactly coincides with the center of curvature of the grooves in the bearing rings 25, means being provided for this purpose for adjustably raising or lowering the housing 2l carrying the pivot screws 32. An angular position of the holders 3l and elements 35 illustrating this pivotal movement is shown in Fig. 10. For the purpose of vertically adjustably positioning the housing 2 I, referring to Fig. 1, the front and rear walls Zia of the housing are provided With pairs of depending lugs 2Id having camming surfaces on their under sides engaging cams 31a of a cam frame 31 slidably carried on tracks 38 and adjustable by means of a screw 39 passing through the end wall 2Ilb of the base and having a knurled handwheel 43. Preferably the depending lugs 2Id are provided with downwardly extending lips 2le for guiding them on the cams 31a. To provide for vertically accurate movement of the housing 2| the front and rear walls 2 la thereof have apertured lugs 4l for sliding on guide posts 42 which are rigidly mounted on the sub-base S.

By this construction it is possible to adjust the heights of the pivot screws 32 to suit the various sizes of bearing rings placed in the machine. Referring to Fig. 9, the housing 2l is shown in a low position wherein the pivot screws 32 are aligned with the centers of the radii of comparatively small bearing rings a. In Fig. l0 the housing 2| is shown in an intermediate position to accommodate the machine for the medium sized bearing rings 2517, :and in Fig. 11 the housing is shown in an elevated position to accommodate the machine for large sized rings 25e, these various positions being attained by turning of the knurled wheel to operate the camming frame 3l.

For the purpose of oscillating the holders 3S and finishing elements 35 carried thereby, a cam drive is provided from the pulley 3D to the driving link 33. As shown in Fig. l, a worm 43 is mounted to rotate with the pulley 33 and engage a worm gear 44 mounted on a spindle 45 carried in brackets 46 integral with the end wall 23h of the base. Also, mounted on the spindle is a heartshaped cam 41 engaged by a roller 43 carried by one end of a pivotally mounted arm 49 the other end of which carries a roller 50 extending into a goose neck 5l on the end of the driving link 33, the sliding engagement provided by the goose neck 5I permitting vertical adjustment of the housing 2| by the cam frame 3l. As shown in Fig. 1, the arm 49 pivots on one of the brackets 43 carried by the wall 20h of the base, and for the purpose of maintaining the roller 48 in engagement with the cam 41 a coil spring 52 is connected from the wall 20D to the arm.

According to the present invention link means are provided for individually applying pressures to the oscillating caps 36 and sleeves 34 to be transmitted to the finishing elements 35 in such a manner that the latter will exert substantially equal and uniform pressures on the grooved surfaces of the bearing rings 25.

As shown in Figs. 1 and 2, the housing 2i carriesa plurality of vertical slides 53 mounted by pairs of shouldered screws 54 extending through slots 55 in the rear Wall 2| a of the housing. At its lower end each slide 53 pivotally carries a pressure-transmitting or connecting arm 53 eX- tending upwardly along the inner side of the slide and having a laterally extending convexed portion 56a engaging a cylindrical slot in the cap 35. The slides 53 also have laterally extending arms 53a engaging the underside of an inflatable tubular bag 51 provided with a nipple connection 58. According to this construction, when the bag 57 is inflated its underside will bear against the arms 53a of the slides 53, providing a downward pressure thereon. This pressure is transmitted tothe connecting arms 53 and thence to the caps 36 and sleeves 34. As a result, a pressure is applied to the finishing elements S5, causing their lower ends to bear against the grooves of the bearing rings 25. It will be noted, referring to Fig. l0, that the pressure transmitted from the slides 53 to the finishing elements 35 is variable due to the angularity of connections at the ends of the connecting arms 55. When the holders are in their vertical position, as shown in Fig. l, the pressure applied to the slides 53 will be transmitted substantially without change to the finishing elements 35. When the holders 3l are `in an angular position, as shown in Fig. 10, pressure Iapplied to the slides 53 will be only partially transmitted to the finishing elements due to a horizontal component of pressure being present. However, for the angular position of Fig. 10 the slides 53 arerelevated slightly, as compared to the Fig. l position, so that the bag 5l is compressed. This increases the pressure exerted by the bag on the slide, and as a result a compensating effect is had whereby the resultant pressure exerted by the finishing elements on the bearing rings may be maintained substantially uniform.

ft will be noted that the inflatable bag 5l thereby causes pressures to be applied individually to the finishing elements 35, these pressures being all equal and substantially uniform throughout the oscillating movement of the elements. As a result, the amount of material removed from each of the grooves of the bearing rings 25 will be substantially equal, providing the finishing elements S5 are all of equal coarseness or fineness. Even if one or several of the finishing elements were to wear slightly more rapidly than the others, the difference in the positions of the sleeves 34, connecting arms 56, and slides 53 would not cause appreciable differences in the pressures on the rings 25, since the resilience of the lower wall of the bag 5l is able to accommodate different positions of the slide, and since the hydraulic pressure at all points on the lower wall of the bag is substantially equal regardless of slight Variations of position. Close control of the finishing of the bearing grooves is possible due to the ease with which the pressures of the elements may be controlled, by controlling the hydraulic pressure in the bag 5l, which may be done by any of numerous well-known devices,

For certain conditions it may be desirable to clean out the sides of the grooves more than the bottom, or vice-versa, and the adjustment for raising or lowering the housing 2l may be utilized for this purpose. For, if the pivot points of the holders 3i are located either above or below the centers of curvature of the grooves in the races, the material removed from the groove will vary accordingly. As an example, if a group of rings s to be finished in which the grooves are somewhat egg-shaped, this condition may be corrected in the finishing by properly locating the pivot points about which the nishing elements swing.

When the stones 35 become worn, their usefulness may be extended by providing shims 35a under the caps 36, as shown in Fig. 2, and the condition of the stones during operation of the machine ma'y be observed through a window Zig, Fig. 4, provided in the front wall 2 la of the housing.

The machine may be shut ofi after a predetermined number of oscillating movements of the finishing elements have been made by any suitable stop means.

For the purpose of providing access to the holders 3| and finishing elements 35 carried thereby, the housing 2| is made to part along a horizontal plane 59, Figs. 1 and 2, the rear wall 21a of the housing being provided with a. hinge 60 at this parting line. Referring to Fig. 2, a latch plate 6| and latch pin 62 are carried rigidly mounted on the portion of the housing 2| below the plane 59, the pin being engaged by a latch arm 63, mounted on the upper portion of the housing, and having an upwardly extending handle 63a. Thus, as shown in Fig. 8, the top portion of the housing 2| including the bag 5'|, slides 53 and arms 56, may be swung backward, the portions 56a of the arms becoming disengaged from the caps 36. The holders 3|, sleeves 34 and caps 36 are now exposed, and to remove the elements 35 it is only necessary, to lift the sleeves carrying same out of the holders. As shown in Fig. 2, the caps 36 have apertures 36a to permit insertion of apunch for facilitating removal of the elements from the sleeves. Quick and convenient changes of elements may therefore be made as a result of this construction. For the purpose of providing for convenient re-engagement of the arms 56a and caps 36 when the housing is t be closed, all of the connecting arms 56A are held in central alignment during the open position of the housing 2| by a movable bail 64, which is mounted on arms 65 connected with the latch 63, the bail extending under the end portions of the extensions 56a of the arms to engage same when the latch is in releasing position. Thus, when the holders 3| are centralized, the extensions 56a of the arms will be properly positioned for engaging the caps 36 as the top of the housing is closed. A coil spring 66 yieldably holds the latch in closed or looking position, and a pivotally mounted am 61 is provided for engaging a pin 61a to hold the latch in releasing position.

To provide for quick and convenient insertion and removal of mandrels 24 carrying the bearing rings 25, the housing 2| is made to part along a second horizontal plane 68 substantially in alignment with the axis of the mandrel.

Referring to Fig. 2, the rear wall 2|a of the housing is provided with a hinge 69 to permit the portion above the plane 68 to be swung backward as shown in Fig. 7, providing access to the mandrel-and-bearing assembly. The reciprocating drive for the link 33 permits this opening of the housing is provided 'with a hinge 69 to permit the fork or gooseneck 5| and the roller 50. The front wall Zia of the housing is provided With a pivotally mounted latch arm T8 for engaging a flange 1| to normally hold the housing in the closed operating position shown in Fig. 2. Also, the bearing 26 for the mandrel is formed in two parts, Figs. 5 and 6, the upper part or cap 26a being hinged on the end wall 20c of the base so that it may be swung open to permit removal of the mandrel, as shown in Fig. 6. To provide for opening the split bearing 26 automatically with swinging of the housing 2| about the hinge 69, the cap 26a has an upwardly extending fork 2Gb coope ating with a pin 2li carried by the end wall 2|c of the housing. When the machine is in the operative position partly shown in Fig. 5, the bearing cap 26a is rmly held closed by the stud 2| f and when the housing 2| is swung backward, as shown in Fig. 6, the cap will also swing upward and backward and leave the bearing open for removal of the mandrel.

To provide for proper axial positioning of the mandrels 24, and to prevent end play, the ends 24h of the mandrels are preferably provided 'with grooves 24o, Fig. l, and the separable parts of the bearing 26 are provided with dog-point screws I2 adapted to extend into the grooves.

After a set of bearing rings 25 on a mandrel 24 has gone through the finishing operation, the housing 2| may be swung backward about the hinge 69 by first releasing the latch 10, whereupon the mandrel and bearing rings may be removed and another mandrel already prepared with unfinished rings inserted in the machine for iinishing.

Although only ve rings and the reciprocating assemblies for iinishing same are shown in Fig. 1, it should be understood that a much greater number of rings and assemblies may be used in a single machine, and as a result the productivity of the machine may be quite high since a large number of rings may be finished simultaneously in one operation.

Referring to Fig. 2, for the purpose of supplying coolant to the bearing rings 25 at their points of engagement with the finishing elements 35, a manifold pipe 82 is mounted on the inside of the rear wall 2| a of the hou-sing and connected through a pump (not shown) to a suitable coolant reservoir. Also, a second manifold pipe 83 is mounted on the front wall 2|a of the housing for the purpose of providing a cleaning solution where this might be desirable, preparatory to subsequent finishing operations on the bearing rings 25.

A tray 84 is mounted under the mandrel 24 and rings 25, supported by legs 85, Fig. 2, to receive and carry olf the coolant, or to supply additional coolant to the rings when the latter` dip below the level of the solution.

As may be understood, wear at the pivot points of the screws 32 supporting the holders 3| may be taken up by tightening the screws, and if desired the pivots may be sealed to exclude abrasive grits, etc.

A modified form of holder for the finishing elements is shown in Fig. l2 wherein a pair of elements may be brought to bear against each of the bearing rings 25. The holder 'I4 shown in this figure has a pair of parallel bores slidably carrying sleeves 15 in which are frictionally mounted iinishing elements '.16. To provide for an equalized pressure on each of the elements 'I6 a ballpointed bridging member 1? is provided, engaging the caps 18 of the sleeves "l5, the member T.' being pivotally connected to the extension 19 of the connecting arm 80. According to this construction, pressure exerted by the bag 5'! on the slide 8| will be transmitted through the connecting arm and bridging member 11 to be divided equally between the finishing elements 16.

By the provision of two finishing elements for each bearing race the amount of wear per element is reduced to approximately one-half, and therefore replacement or readjustment of the elements need not be made so frequently. Also, the time of finishing of the bearing rings may be reduced. This arrangement is especially advantageous for use with the larger sized bearing rings, and the elements may be located close to each other so that they sweep the grooves transversely substantially along their arcs. Also, the finishing elements or stones 16 may have a rectangular cross-section equaling together the cross-section ascaoae of a single finishing element, in which case the contacting surfaces of the elements may more nearly conform to the contour of the grooves at all points.

Variations and modifications may be made Within the scope of this invention and portions of the improvements may be used without others.

l claim:

l. A machine for linishing grooves in Workpieces, having means for supporting and simultaneously travelling a plurality of ganged grooved workpieces; a plurality of holders for carrying and presenting finishing elements to the grooves of the workpieces; and means for simultaneously moving each of the holders to cause the finishing elementsto sweep and traverse the surfaces of the grooves as the workpieces are travelled relative to the finishing elements.

2. A machine for finishing grooves in workpieces, having means for supporting and simultaneously travelling a plurality of ganged grooved workpieces; a plur-ality of holders for carrying and presenting finishing elements to the grooves of the workpieces; means for moving the holders to cause the finishing elements to sweep and traverse the surfaces of the grooves as the Workpieces are travelled relative to the finishing elements; and means uniting the holders for simultaneous and corresponding movements.

3. A machine for iinishing grooves in workpieces, having means for supporting and travelling a plurality of ganged grooved workpieces; a plurality of holders for carrying and presenting finishing elements to the grooves of the Workpieces; means for moving the holders to cause the finishing elements to sweep and traverse the surfaces of the grooves as the Workpieces are travelled relative to the finishing elements; and means for yieldingly urging all of the elements against the work with substantially uniform and constant pressure.

4. A machine for iinishing concave grooves in workpieoes, having means for supporting and rotating a plurality of ganged grooved workpieces;

a plurality of holders for pivotally carrying and presenting nishing elements to the grooves of the workpieces; and means for simultaneously swinging the holders to cause the finishing elements to sweep and traverse the surfaces of the grooves as the Workpieces are rotated relative to the nnishing elements.

5. A machine for finishing concave grooves in workpieces, having means for supporting and rotating a plurality of ganged grooved workpieces; a plurality of holders for pivotally carrying and presenting finishing elements to the grooves of the workpieces; means for simultaneously swinging each of the holders to cause the nishing elements to sweep and traverse the surfaces of the grooves as the workpieces are rotated relative to the finishing elements; and means for simultaneously adjusting the pivot points of the holders to accommodate workpieces of dierent diameters and having different radii of groove curvature.

6. A groove-iinishing machine having a base; a carrier for mounting on the base a plurality of grooved workpieces in tandem for longitudinal movement of the grooves thereof; iinishing elements adapted to engage the grooves of the workpieces; means for mounting the elements on the baserfcr pivotal movement about the centers of curvature of the grooves of the mounted workpieces respectively so that portions of said elements may engage and sweep the grooves transversely, said mounting means permitting advancing movement of 'the elements; means for imparting continuous movement to the carrier'and mounted workpieces and for simultaneously reciprocating the finishing elements 'about the said centers of curvature; and means carried by the base for applying substantially identical pressures individually to the finishing elements While they are reciprocating, for causing them t0 ad- Vance and bear against the grooves of the work pieces for ,finishing the latter.

Y 7. lThe invention as deiined in claim 1 in which the means for applying pressures to the elements comprises a hydraulic chamber, and individually operable pressure-transmitting links between the chamber and the elements respectively,

8.- Th'e invention as defined in'claim 1 in which the means for applying pressures to the elements comprises a hydraulic chamber, and individually operable two-part pressure-transmitting links between the chamber and the elements respectively, each of said links comprising a slide operatively connected with the chamber, and an arm pivotally connected to the slide and the element, and reciprocating with the latter, the pivotal movement of the arm periodically moving the slide to cause periodic compression of the hydraulic chamber and consequent increase in pressure applied thereby, and the angularity of the arm with respect to the slide during such periods of increased pressure functioning to reduce the'pres- 'sure transmitted'to the element so that a compensation .is effected to provide for uniformity of pressure on the element throughout its reciprocation.

9. A groove-finishing machine having a base; a carrier for mounting a grooved workpiece on the base for longitudinal movement of the groove thereof; an elongate nishing element adapted at one end to engage the groove of the workpiece; a holder carrying the element, pivotally mounted so that the element may swing about a point intermediate its ends whereby the said groove-engaging end may transversely sweep the groove of the workpiece, said holder permitting advancing movement of the element; means for imparting continuous movement to the carrier and mounted workpiece, and for simultaneously reciprocating the holder and iinishing element; a pressure-transmitting link connected at one end to apply pressure to the free'end of the element; a slide mounted on the base, pivotally connected to the other end of the link to permit the latter to swing with the holder and element; and an inflatable container mounted on the base, connecting with the slide for applying pressure thereto, said pressure being transmitted through the link to the iinishing element as the latter reciprocates, for causing same to advance and bear against the groove of the workpiece.

l0. The invention as defined in claim 9, in which there are means for changing the position of the carrier with respect to the holder so that the pivot point lof the latter may be made to coincide with the centers of curvature of the grooves in different-sized workpieces,

ll. A groove-nishing machine having a base; a carrier for mounting on the base a grooved workpiece; means for demountably mounting the carrier on the base for movement of the workpieces longitudnally ofthe groove of the Workpiece carried thereby; a iinishing element adapted to engage the groove of the workpiece; means for mounting the element for pivotal movement about the center of curvature of the -groove of the mounted workpiece so that portions of said element may engage and sweep the groove transversely, said mounting means permitting advancing movement of the element; means for imparting continuous movement to the carrier and workpiece, and for simultaneously reciprocating the finishing element about the said center of curvature; means for applying pressure to the finishing element while it is reciprocating, for causing it to advance and bear against the groove of the workpiece; and means for adjusting the position of the pivot point so that when the workpiece is replaced in the carrier by a differentsized workpiece the pivot point may be made to coincide with the center of curvature of the replacing workpiece.

12. A groove finishing machine having a base; a carrier for demountably mounting a grooved workpiece on the base for movement of the workpiece longitudinally of the groove thereof; a housing carried by the base; a finishing element adapted to engage the groove of the workpiece; means for mounting the element on the housing for pivotal movement about the center of curvature of the groove of the workpiece so that portions of the element may engage and transversely sweep said groove, said mounting means permitting advancing movement of the element; means for imparting continuous movement to the carrier and mounted workpiece, and for simultaneously reciprocating the element about the said center of the curvature; means for applying pressure to the finishing element while it is reciprocating, for causing it to advance and bear against the groove of the workpiece; and means for demountably connecting the base and housing together whereby the housing may be shifted to separate the finishing element from the workpiece so that the latter is free for removal.

13. A groove-finishing machine having a base; a carrier for mounting a grooved workpiece on the base for longitudinal movement of the groove thereof; an elongated finishing element adapted at one end to engage the groove of the workpiece; a holder carrying the element, pivotally mounted on the base so that the element may swing about a point intermediate its ends whereby the said groove-engaging end may transversely sweep the groove of the workpiece, said holder permitting advancing movement of the element; means for imparting continuous movement to the carrier and mounted workpiece, and for simultaneously reciprocating the holder and finishing element; a pressure-transmitting link connected at one end to apply pressure to the free end of the element; a slide mounted on the base, pivotally connected to the other end of the link to permit the latter to swing with the holder and element; and yieldable means carried by the base for applying a pressure to the slide, said pressure being transmitted through the link to the finishing element as the latter reciprocates for causing same to advance and bear against the groove of the workpiece.

14. A groove-finishing machine having a base; a carrier for mounting on the base a plurality f grooved workpieces in tandem for longitudinal movement of the grooves thereof; finishing elements adaptedto engage the grooves of the workpieces; means for mounting the elements for pivotal movement about the centers of curvature of the grooves of the mounted workpieces respectively so that portions of said elements may engage and sweep the grooves transversely, said mounting means permitting advancing movement of the elements; means for imparting continuous movement to the carrier and mounted workpieces and for simultaneously reciprocating the finishing elements about the said centers of curvature; an inflatable container mounted on the base, and fluid conducting means for inflating same; and means for transmitting pressure from the bag when inflated to the finishing elements individually while the latter are reciprocating forcausing the elements to advance and bear against the grooves of mounted workpieces for finishing the latter.

15. A groove-finishing machine having a base; a carrier for mounting a grooved workpiece on the base for longitudinal movement of the groove thereof; an elongate finishing element adapted at one end to engage the groove of the workpiece; a holder carrying the element, pivotally mounted on the base so that the element may swing about a point intermediate vits ends whereby the said groove-engaging end is adjacent the workpiece and may transversely sweep the groove thereof, said holder permitting advancing movement of the element and retracting movement for withdrawal entirely from the holder; means for imparting continuous movement to the carrier and mounted workpiece, and for simultaneously reciprocating the holder and nishing element; a pressure-transmitting link demountably connected atv one end to apply pressure to the end of the element farthest from the workpiece; a housing carried by the base; a slide mounted on the housing, pivotally connected to the other end of the link to carry same and permit it to swing with the holder and element; an inflatable container mounted on the housing, connecting with the slide for applying pressure thereto, said pressurebeing transmitted through the link te the finishing element as the latter reciprocates, for causing same to bear against the groove of the workpiece; and means for demountably connecting the base and housing together whereby the housing may be shifted from operating position to bodily move the slide and link and separate the latter from the finishing element so that the element is freefor removal from the holder.

16. The invention as defined in claim 15 in which the connection between the link and iinishing element includes meshing parts carried by said link and element, and in which there are means for holding the link, when the housing is shifted from operating position, in a setting corresponding to a predetermined position of the element, so that the said parts may be aligned for meshing when the element is maintained in said predetermined position and the housing is returned to operating position.

17. A groove-finishing machine for ball bearing races, having a base; a carrier for mounting a. plurality of bearing races axially aligned on the base for simultaneous rotation about their common axis; finishing elements adapted to engage the grooves of the races; means for mounting the elements for pivotal movement about the centers of curvature of the grooves of the mounted races Arespectively so that portions of said elements may engage and sweep the grooves transversely, said mounting means permitting advancing movementof the elements; means for rotating the carrier and bearing races mounted thereby, and for simultaneously reciprocating the finishing elements about the said centers of curvature; an inflatable resilient bag mounted on the base, and fluid conducting means for inflating same; and means for transmitting pressure from the container when inated to the finishing element individually while the latter are reciprocating, for causing the elements to advance and bear against the grooves of mounted races for finishing the latter.

18. A groove-finishing machine having a base; means for movably mounting on the base a workpiece for longitudinal movement of the groove thereof; finishing elements adapted to engage the groove of lthe workpiece; aholder carrying a plurality of elements, mounted for pivotal movement about the center of curvature of the groove of the workpiece so that portions of said elements may engage and sweep the groove transversely, said holder permitting advancing movement of the elements; means for imparting continuous movement to the carrier and mounted workpiece and for simultaneously reciprocating the holder and finishing elements about the said pivotal points; and means for applying substantially uniform pressure to the finishing elements while they are reciprocating, for causing said elements to bear against the groove of the workpiece and finish same.

19. A groove-finishing machine for ball bearing races, comprising a base; a mandrel rotatably mounted on the base, having means for clamping thereon a plurality of bearing races side by side so that the grooves thereof may be located on predetermined centers; a housing mounted on the base; finishing elements adapted to engage the grooves of the races; holders carrying the elements, mounted on the housing to pivot about centers respectively in lateral alignment with the predetermined centers of the bearing grooves, said holders permitting advancing movement of said elements; means for rotating the mandrel and clamped races, and for simultaneously reciprocating the holders to cause portions of the elements to sweep the grooves transversely; means carried by the housing for applying substantially uniform pressure to the iinishing elements while they are reciprocating, for causing them to advance and bear against the grooves of the clamped races; and means for adjusting the housing on the base laterally of the mandrel so that the said pivotal centers of the holders may be made to coincide with the centers of curvature of the grooves of the races clamped on the mandrel, to provide for uniform finishing of the grooves by the said elements.

20. A groove-finishing machine having a base; a carrier for mounting a grooved workpiece on the base for longitudinal movement of the groove thereof; an elongate iinishing element adapted at one end to engage the groove of the workpiece; a holder carrying the element, pivotally mounted on the base so that the element may swing about a point intermediate its ends whereby the said groove-engaging end may transversely sweep the groove of the workpiece, said holder permitting advancing movement of the element; means for imparting continuous movement to the carrier and mounted workpiece, and for simultaneously reciprocating the holder and finishing element; a pressure-transmitting link connected at one end to apply pressure to the free end of the element; a slide mounted on the base, pivotally connected to the other end of the link to permit the latter `to swing with the holder and element; and yieldable means carried by the base for applying a pressure to the slide, said pressure being transmitted through the link to the finishing element as the latter reciprocates for causing same to advance and bear against the groove of the workpiece, the swinging movement of the link periodically moving the slide to cause periodic increases in the pressure applied thereto by the said yieldable means, and the angularity of the link with respect to the slide during such periods of increased pressure functioning to reduce the pressure transmitted to the element so that a compensation is effected to provide for uniformity of pressure on the element throughout its reciprocation.

21. A groove-nishing machine having a base; a carrier for demountably mounting a grooved workpiece on the base for longitudinal movement of the groove thereof; a housing carried by the base; an elongate finishing element adapted at one end to engage the groove of the workpiece; a holder carrying the element, pivotally mounted on the housing so that the element may swing about a point intermediate its ends whereby the said groove-engaging end may transversely sweep the groove of the workpiece, said holder permitting advancing movement of the element; means for imparting continuous movement to the carrier and mounted workpiece and for simultaneously reciprocating the holder and finishing element; a pressure-transmitting link connected at one end to apply pressure to the free end of the element; a slide mounted on the housing, pivotally connected to the other end of the link to permit the latter to swing with the holder and element; an inflatable bag mounted on the housing, connecting with the slide for applying pressure thereto, said pressure being transmitted through the link to the finishing element as the latter reciprocates, for causing same to advance and bear against the groove of the workpiece; and means for demountably connecting the base and housing together whereby the housing may be shifted to bodily move the holder and separate the finishing element from the workpiece so that the latter is free for removal.

22. A groove-finishing machine having a base; a carrier for mounting a grooved workpiece on the base for longitudinal movement of the groove thereof; a housing mounted on the base; a finishing element adapted to engage the groove of the workpiece; means for mounting the element on the housing to pivot about an axis parallel to the path of movement of the groove of ,the workpiece at at least one point, said mounting means permitting advancing movement of the element; means for imparting continuous movement to the carrier and mounted workpiece, and for simultaneously reciprocating the element to cause portions of the latter to sweep the groove of the workpiece transversely; means carried by the housing for applying a pressure to the finishing element while it is reciprocating, for causing it to advance and bear against the said groove; and means for adjusting the housing on the base, including cams on one of said parts and a screwoperated cam frame slidable on the other part, so that the said pivotal line of the element may be made to coincide with the center of curvature of the groove of the workpiece mounted in the carriery to provide for uniform finishing of the groove by the said element.

23. A groove-finishing machine for ball bearing races, having a base; a mandrel having means for clamping a bearing race thereon; means for demountably mounting the mandrel for rotation on the base, including a split bearing block having a hinged cap; a housing carried by the base; a finishing element adapted to engage the groove of the race; means for mounting the element on the housing for pivotal movement about the cen-y ter of curvature of the groove of the race so that portions of said element may engage and sweep the groove transversely, said mounting means permitting advancing movement of the element; means for rotating the mandrel and clamped race, and for simultaneously reciprocating the finishing element about the said center of curvature; means for applying pressure to the finishing element while it is reciprocating, for causing it 10 to advance and bear against the groove of the clamped race; means for hinging the housing on the base whereby the housing may be swung to separate the nishing element from the bearing race to provide access to the latter and the mandrel; and a driving connection between the housing and the hinged bearing cap so that when the housing is swung, the cap follows and opens the split bearing, to permit removal of the mandrel.

THOMAS MARREN.