US686599A

US686599A - Machine for grinding gear-generating cutters.

Info

Publication number: US686599A
Application number: US72171199A
Authority: US
Inventors: Edwin R Fellows
Original assignee: Individual
Current assignee: Individual
Priority date: 1899-06-24
Filing date: 1899-06-24
Publication date: 1901-11-12
Anticipated expiration: 1918-11-12

Description

No. 686,599. Patented Nov. I2, [90L E. R. FELLOWS. I MACHINE FOR GRINDING GEAR GENERATING CUTTERS.

, (Application filed June'24, 1899.) (No Model.) I ll Sheets-Sheet l.

EEI' INVEV/ZNTEIRZ Patented Nov. I2, 19m.

E. B FELLOWS. MACHINE FOR GRINDING GEAR GENERATING GUTTERS.

(Application filed June 24, 1899.) I

ll Sheets-Sheet 2.

(No Model.)

INVENTEI R a z 'm/ i w gmrzasrzsz No. 686,599. Patented Nov. I2, I90I. E. R. FELLOWS. MACHINE FOR GRINDING GEAR GENERATING CUTTEBS.

(Application filed June 24, 1899.)

ll SheetsSheet 3.

(No Model.)

. S. I ill. II: I i

- 7 Patented Nov. l2, I901 E. R. FELLOWS. MACHINE FOR GRIND ING GEAR GENERATING GUTT (No Model.)

EBS.

(Application filed June 24, 1899.)

ll Sheets-Sheet 4 i "T IIHHI llnlfi lll III M 1 I "a i J TUBA- YINVENTDR: 6M 6 541% No. 686,599. Patented Nov. I2, I90l. E. R. FELLOWS.

MACHINE FDR GRINDING GEAR GENERATING CUTTERS.

(Application filed June 24, 1899.)

Patented Nov. l2, I901.

E. R. FELLOWS. MACHINE FOR GRINDING GEAR GENERATING GUTTERS.

(Application filed June 24, 1899.)

ll Sheets-Shoet 6.

(No Model.)

'INVENTEIRI W QZLM No. 686,599; Patented NOV. I2, I90I. E. R. FELLOWS. MACHINE FOB GRINDING GEAR GENERATING CUTTERS.

(Application filed June 24, 1899.)

(No Model.)

ll Sheets-Sheet 7.

.R mi 3mm; 5 5 7 WITN E55 E51 Patented Nov. l2, I9OI.

E. n. FELLOWS. MACHINE FOR GRINDING GEAR GENERATING CUTTERS.

(Application filed June 24, 1899.)

II Sheets-Sheet 8 (No Model) u m .0 Er M 2 6 A W 0 5 My 5 5 5m. 5 W2 No. 686,599. Patented Nov. l2, I90l. E. R. FELLOWS. MACHINE FOR GRINDING GEAR GENERATING CUTTEIIS (Application filed June 24, 1899.)

II Shee'ts-Sheet 9.

(No Model.)

INVENTEI R ww ufl k zm v\X/l-rm ESSESZ m @f y No. 686,599. Patented Nov. l2, I90I. E. R. FELLOWS. MACHINE FOR GRINDING GEAR GENERATING GUTTERS.

(Application filed June 24, 1899.)

II Sheets Sheet I0.

(No Model.)

INVENTEI R;

WITNESSES; I @WWW Patented Nov. I2, I90I.

E. R. FELLOWS. MACHINE FOR GRINDING GEAR GENERATING CUTTERS.

(Application filed June 24, 1899.)

II Sheets$heet ll.

(No Model.)

\IIIIIIIIIIWIII UNITED EDWIN R. FELLOWS, or SPRINGFIELD, VERMONT.

MACHINE FOR GRINDING GEAR-GENERATING CUTTERS PATENT, OFFICE.

SPECIFIGATTON forming part of Letters Patent No. 686,599, November 12, 1901.

Application filed June 24', 1899.

metal-planiu g cutter havinga continuous circular series of radiating or outwardly-projectihg metal-planing teeth of uniform size, whose cutting edges are at the ends of the teeth on the face of the cutter, the backs of the teeth being inclined ataslight clearance- .angle to the axis of the cutter to give the cutter the clearance of metal-planing tools.

A cutter of the character specified is adapted for use in generating-gears by the method described in United States Letters Patent No. 579,708, granted to me March 30,1897, which show a machine in which are combined a metal-planing cutter having a circular series of radiating or outwardly-projecting gearshaped metal-planing teeth, a blank holder provide a machine for finishing cutters of the character described-that is, for treating a cutter blank which has had its teeth previously roughed out and hardened in such a manner as to bring said teeth to their correct size and shape. The invention-is 'not, however, limited in its application to finishing gear-shaping cutters, as it may also be employed in grinding the teeth of bevel and other gears which have been hardened and are hence diflicult to attack bymeans of a metal-planing tool.

The invention involves the employment of an abrasive generating-wheel, a holder for the line 3 3 of Fig. 1.

Serial For 721,711. (No model.)

the cutter, means for imparting a rolling motion to said holder to cause it to roll over and bring one of its teeth to contact with the face of the generating-wheel, whereby the side of the tooth is ground to its correct curvature, and means for indexing the cutter-holder or turning it on its own axis to bring the teethof the cutter successively into position to be Tic ground.

Of the accompanying drawings, Figure 1 represents a front elevation of a simple form of machine embodying my invention. .Fig. 2 represents a plan view thereof. Fig. 3 represents a longitudinal section therethrough on Fig. 4 represents a front elevation, partly .in section,-showing a more elaborate embodiment of my invention in the'form of an automatic machine, the cutter being shown as retracted from the grinder. Fig. 5 represents a view similar to the foregoing with parts in section, the cutter being shown in contact with the grindeiu, Fig. 6 represents a plan view of the machine. Fig. 7 represents a rear elevation with parts broken away and parts in section. 1 Fig. 8 represents;' a-sectionon line 8 8 of Fig. 5.. Fig. 9 repre sents a right end elevation. Fig. 10 repre-j sents a detail plan view of the cylindrical '80 roller and tapes governing the cutter-spindle. Fig. 11 represents a transverse sectional view of said roller with its slide and adjacent parts. Fig. 12 represents a left end elevation of the machine. Fig. 13 represents a detail plan 8 view of the diamond holder and adjacent parts employed in facing the grinder, said device being omitted in certain previous figures for the sake of c'le'a'rness. Fig. 14 represents a side elevation of said parts. Fig. .15 repre- 9o sents a view corresponding to Fig. 11, showin g a modification, hereinafter referred to, for moving the roller tape-bars v The same reference characters indicate the same parts in all the figures. 5 Referring for the present to Figs. 1, 2, and 3, a-designates the base or frame of the machine, and b designates the spindle'or arbor,

to the end of which the, cutterc is clamped? The cutter is held between asho'ulder b? on the spindle and a ring-or washer b ,"against which a nut b3, engag'ing the threaded end of the spindle, is-screwed. H d designates a generating-wheel,such'as an emery-wheel, for grinding the cutter-teeth,

said wheel having an edge thin enough to The cutter c is of the form referred to,

having radial or outwardly-projecting gearshapcd teeth 0' c, the cutting edges of which are on their front ends 5 and the crests 6 of which are inclined at a slight angle to the axis of the cutter, giving the'teeth the clearance of ordinary metal-planing tools, while the sides 7 of the teeth when ground will have a convergence which gives them side clearance, there being thus imparted to the cutter the general form of a bevel-gear. The large end of the cutter is preferably slightly dished to give the teeth the ordinary rake of metalplauing tools.

In carrying out my invention as hereinafter described I employ the principle of generating an involute tooth by the action of an imaginary rack having teeth of the form of a truncated wedge. The face 2 of the emerywheel d corresponds to the side of one tooth of the rack.

The spindle b, which carries the cutter, is mounted in an elongated bearingsleeve b, which has two conical surfaces 3 and 4 turned on it near its front and rear ends and forming parts of the pitch-cone of the bevel-wheelshaped cutter. These surfaces are adapted to roll on two flat bars a a attached to the frame aand forming a supporting plane surface for the cone, and between the conical surfaces and the bars are interposed two pairs of thin flat tapes or bands e e e e, preferably made of steel, so as to be inextensible and attached at their inner ends to the sleeve 11' by screws e e and at their outer ends to the bars a a by screws e e. \Vhen rolling motion is imparted to the sleeve, one tape in each set winds up on the sleeve while the other tape unwinds, thus causing said sleeve and the cutter to turn on their own axis, the resultant being a rolling motion with the apex of the pitch-cone as a center. During this movement the axis of the spindle b generates aconical surface. Endwise play of the sleeve is prevented by a spring b surrounding the same and abutting at its rear end against a shoulder on the sleeve and at its front end against a loose collar D which abuts the tapebar a b is a collar keyed to the rear end of the sleeve 12', and b is a handle projecting therefrom and adapted to be grasped to impart the rolling movement to the sleeve. Said rolling movement results in reciprocating the cutter c toward and from the emery-wheel d. On the movement of the cutter toward the emerywhcel the side of one of its teeth 0 will roll over int-o contact with the face 2 of said wheel,

and the latter will grind an involute surface thereon. If the upper surfaces of the tapebars a 0!. were parallel to the axis of the emery wheel, the curve generated on the tooth would be that mating with a rack haying square teeth or teeth of no angle; but in order to give the cutter-teeth their proper obliquity I incline the tape-bars at an acute angle to the axis of the emery-wheel, as shown in Fig. 1, which is equivalent toinclining the imaginary rack of which the emery-wheel represents one tooth; When the emery-wheel reaches the root of the cutter-tooth, its face 2 is radial with the center of the cutter c, as represented in Fig. 1. 4

On the rear end of the cutter-supporting spindle bis secured an indexing-wheel f, provided with teeth around its periphery meshing with a worm f,' having a spindle f, mounted in hearings on a bracket b, which depends from the collar 1), rigidly keyed on the sleeve b. For rotating the worm a short crank f is attached to its spindle, said crank carrying at its end a locking-pin f adapted to enter a hole in a projecting boss b on the collar 1) to lock the worm. Each time the cutter c'is rolled back out of contact with the emery-wheel the locking-pin f is withdrawn and the index-wheel f rotated to turn the spindle b on its axis and bring a fresh tooth of the cutter into position to be ground. The

pitches 0f the index-wheel and of the worm are so related that a given number of revolutions of the crank f will step the cutter ahead exactly one tooth and the locking-pin is employed to fix the cutterin the position thus determined. The stepping of the cutter ahead after each contact with the emerywheel is continued until it has made a complete rotation and has had one side of each of its teeth ground. The grinding of the opposite sides of the cutter-teeth is preferably done on another machine having an arrangement of emery-wheel and inclined tape-bars the reverse of that on the machine described; but the parts of the present machine may obviously be made adjustable, so that all the grinding can be done on the one machine.

It will be evident from the foregoing description that the grinding-machine illustrated in Figs. 1, 2, and 3 may be employed in grinding hardened bevel-gears as well as gear-shaping cutters. Cutters of the kind under consideration are usually narrow, and in grinding them it is not found necessary to efiect any relative longitudinal motion of the emery-wheel as a whole and the cutter. The wheel merely sweeps over the surface of the cutter-tooth; but in adapting the machine for grinding bevel-gears I prefer to mount the emery-wheel in a movable bearing, such as shown in the drawings, so that the wheel as a whole can be moved along the tooth of a wide gear to grind the whole length of said tooth. For this purpose the bearing or sleeve (1 supporting the emery-wheel is mounted to slide forward and back on a guide (1 on the frame a and is provided with a rack 01 whose teeth mesh with those of a stationarily-mounted pinion (1, turned by means of a handle d.

Having explained the elements and operation of my invention by the description of a simple hand-operated machine constructed in accordance therewith, I now proceed to the consideration of an automatic machine embodying the invention and differing in the action of its working parts only by the substitution' of a cylindrical roller carrying the cutter-holding spindle for the conical roller.

of the machine just described and the setting of' the grinding-wheel with its plane at a slight angle to the axis of said roller to give the cutter-teeth their angle of side clearance.

liteferring to Figs. 4 to 12, a. is the machines frame or base, the upper portion of which only is shown.

b is the cutter-spindle, having aholder on its end in which the cutter c isclamped, and dis the grinding-wheel, having an acting face ,2 in a plane at right angles to its axis of rotation. The spindle b is carried in a bearingsleeve 12", having a cylindrical portion 8, to which are attachedoppositely-wound tapes e e, having their outer ends secured to flat-' topped tape-bars a 0. The latter are bolted to the frame in an inclined position, as shown. The bearing-sleeve b is mounted in a slide b, which is adapted to reciprocate in a rectilinear path of an inclination corresponding to that of the tape-bars on a suitable guide on the frame a. The slide is reciprocated by means of abell-crank lever b, one of the arms of which'is connected by a link b with the slide, the other arm being connected by a link b with-a crank b" on a'continuouslyrotating cross-shaft I), mounted in suitable hearings on the frame.

a worm-gear b at its end, meshing with a .worm g on the main drive-shaft g of the machine, which latter is equipped with a cone Said cross-shaft has belt-pulley g. It is evident that the reciprocation of the slide b gives the cutter 0, through the control exercised by the tapes e e,

' the motion required to roll it from the retracted position represented in Fig. 4 over into contact with the grinding-wheel d, as shown in Fig. 5, and back again, causing the grinding-wheel to generate an involute surface on the side of each tooth of the cutter,

the cutter being automatically stepped forward or indexed, one tooth on each backward stroke, by indexing mechanism presently to be described.

The spindle d of the grinding-wheel has a belt-pulley d on its rear end, whereby. it may be rotated and is mounted in a bearing-sleeve d", which is set so as to incline 'the plane of the acting face 2 of said wheel at a slight angle to the axial line of the cutter-spindle, as

represented in Fig. 6, and thereby cause saidwheel to grind the sides of the cutter-teeth with a slight convergence to give the teeth their side-cutting clearance.

By means of this machine cutters such as which a vertical adjustment may be given ters Patent, Serial No. 721,712, filed by me 1 June 24, 1899, can be ground. Said applica- 7o tion describes a cutter having an endless circular series of radial or-o'utwardly-projecting metal-planing teeth, the sides of which converge in the direction of their length and are of equal curvature throughout-that is, supposing the teeth of the cutter to be involute teeth, the side outlines. of a tooth at different points along the length of the tooth will be involutes drawn to base-circles of equal diameter. In this machine the grinding-wheel is set so that its plane will follow the convergent lines of 'the sides of involute teeth and will grind the involute surface and be when in contact tangent thereto. 1

The sleeve cl is carried by a slide d to y a hand-screw (Z to varythe elevation of the grindingwheel, and said slide and handscrew are in turn carriedbya plate (1 A mounted to slide on the side of the frame 01. 9o inithe arc of a circle whose center is at the point occupied by the center of the cutterspindle b when at its forward extreme of position, Fig. 5. By this adjustment the angle of obliquity of the grinding-wheel with re- 5 spect to the cutter may be varied. The plate d is clamped to the frame a by bolts cl d", the bolt d also serving to clamp the slide (1 in position. A segmental tongue (1 on the frame a, fitting in a correspondingly-shaped 10o .groove in the plate (1, serves to'guide said plate. A third adjustment is'p'rovided for the grinding-wheel d by mounting the bearing-sleeve at so as to be capable of sliding onthe slide (1 in the direction of the axis of .105 the wheel, its position being regulated by means of an. adjusting-screw d", against the head ofwhich the sleeve is pressed bya spring] d This adjustment is employed when the) face of the grinding-wheel is trued up by the 1 1o diamond. (Illustrated in Figs. 12, 13, and 14.) The holder or bracket h'for the-diamond h is mounted on top of the slide (1 carrying the grinding wheel (1, but is normally swung aside on its pivot-bolt k to the position shown in broken lines in Fig. 13. When it becomes necessary, however, to true up the acting face of the emery-wheel (I, so as to keep said face a perfect plane, the cutter-operating mechanism is stopped and the bracket h is swung around and fixed in lace with the bolt h and an additional bolt as represented in full lines in Figs. 12, 13, and 14. Thediamond h should be so adjusted in its bracket that when thus positioned it coincides with the proper plane of the emery-wheel face 2. Said Wheel is moved bodily in the direction of its axis by adjusting the screw (1" to bring the face 2 slightly past this plane, and the diamond is then inoved inwardly in a radial 1 0 direction over the face of the emery-wheel by manipulating a screw .72., which projects a slide h on which the diamond is mounted.

The diamond grinds off the surface of the wheel and reduces the face 2 to a true plane. Lateral adjustment of the diamond may be effected when required by manipulating a nut h.

I will now describe the indexing mechanism for rotating the cutter tooth by tooth on its own axis. This rotation takes place after the motion of the slide b has withdrawn the cutter from contact with the emery-wheel and occupies about one-third of the operating time.

f is a large index-wheel attached to the rear end of the cutter-supporting spindle b and formed with teeth on its periphery which mesh with a worm f, carried in bearings on an arm or bracket Z2 rigidly keyed to the rear end of the sleeve b, which supports the spindle I). Said bracket in practice is suitably counterweighted to balance the mechanism carried by it. On the shaft of the worm if is a gear f meshing with a gear f, on

whose shaft is a gear f meshing with a gear f all carried by the bracket I). The shaft of the last-said gear terminates in a universal joint j, which connects it with the inner section 9 of a telescopic shaft f". The outer tubular section 10 of said shaft is splined to the section 9, so that the two rotate together, and is connected bya universal joint f to a short shaft f, which is driven intermittently through gears f f f" f, segmental gear f and bevel-gears f from the continuously-rotating cross-shaft b. The gears f 5 f are change-gears,which may have variouslyrelated diameters, according to the pitch of the cutter which is to be ground. The segmental gear f gives the gears f and f 17 one complete rotation in its passage across the former of them, and they in turn give the worm f a certain number of rotations and cause the index-gear f on the end of the cutter-spindle to make a predetermined fraction of a rotation, the amount of which depends upon the relation of the change-gears f f To the bracket 12" is aflixed a segmental scale or index f over which a pointer f, mounted alongside of the gear f is adapted to sweep. The collar f, Fig. 7, which bears the pointer, is normally loose on the shaft of the worm f and gear f but may be secured thereto by means of a thumb-screw f The pointer and scale are used to calibrate the cutter. In calibrating the thumb-screw f is set up, the gear f 'is loosened on its shaft by throwing over a clamping-lever f and the pointer'is ,moved a predetermined distance across its index, which distance gives a known equivalent rotary movement to the cutter.

It now remains to consider the device for locking the indexing mechanism.

When the cutter has rolled back two-thirds of its stroke away from the emery-wheel and is out of contact therewith, the locking-pin included in said device is automatically withdrawn and the mutilated gear comes into action and rotates the indexing-worm, which rotation continues for the remainder of the back stroke of the cutter and for one-third of its return stroke, after which the said locking-pin again becomes engaged and locks the indexing mechanism. On the same shaft with the gears f and f is a disk 1'', having a segmental portion of its periphery cut away to form two stops or abutments 15 16, with which two shoulders 13 14, located at right angles on a locking-pin i, I are adapted to become engaged, thereby locking said disk, and hence the worm f from rotation in either direction. The pin i is mounted in guides on the bracket b and is normally pressed by a spring '6 into engagement with the notched disk 11'. Release of the pin is efiected by the intermittent action of a dog 1', mounted on a short shaft '5 carried by the bracketb and terminating in a universal joint which connects it with the inner section 11 ofatelescopicshaft t'". The outer tubularjsectionlt? of said shaft is splined to the innersection, so that the two rotate together, and is carried in a tubular bracket i pivoted at 1 to a stud on the machine-frame a. Said outer section 12 of the shaft is provided with shoulders at either end outside of its bearing in the socket i so as to be incapable of moving longitudinally therein, and on its rear end is fixed a segment of a bevel-gear 2', whose teeth mesh with a bevelgear segment 11, formed on a plate 1?, which has the shape of a bell-crank and is pivoted on the stud 7: A cam 1' screwed to the side of the wormgear b, and hence revolving with the shaft b, engages a roll 1? on the bell-crank once in every revolution of said shaft and by such engagement oscillates the bell-crank, rotates the telescopic shaft, and withdraws the locking-pin 'i.' As soon as the cam 2' leaves the roll 1 the pin is returned by its spring into locking engagement with the disk '11.

In Figs. 4, '6, 7, and 8 the parts of the machine have the positions which they occupy when the cutter is rolled back away from the emery-wheel. As the cutter moves forward up its incline the bracketlFand all the parts carried thereby are swung upwardly, so as to occupy the position shown in Fig. 5 when the cutter reaches the limit of its forward movement. During this oscillation of the bracket the telescopic shafts connecting the fixed gearing with the mechanism on the bracket will become extended.

It is evident that with the machine asthus far described cutters of but one diameter of pitch-circle can be ground, said diameter being that of the cylindrical portion 8 of the cutterspindle roller plus the thickness of the tapes 8 a. pitch, the roller might be provided with cylindrical portions of different diameters and corresponding tapes and tape -bars, which bars run loose except when in use, or a mechanism for moving the tape-bars may be pro- IIO To grind cutters.of a different vided such as that illustrated in Fig. 15. The

are connected'by a link e with a bell-cranijrl e", pivoted at e to the frame.

a" is' a slide-i way or guide mounted on an ear b on the, slide b and adapted to be fixed at difierent angles thereon. An arm of the bell-crank e is pivoted to a block e, sliding in the groove of said guide, and the travel of the slide b has by this connection the effect of oscillating the bell-crank and moving the tape-bars in the direction of their length- By varying the angle of the guide e this movement of the bars ma; be made greater or less, and bysetting the guide e" angnlarly to either one side or the other of the path of its movement the bars may be'caused to travel either in the same direction as the slide 1) or opposite thereto. It isevident that the former move-. meut will be equivalent to increasing the diameter of thepitch-circle on which the cut ter rolls, while the latter movement will be equivalent to decreasing the pitch-circle. By substituting a curved guide for the straight guide e'and a rollfor the block e ,a' varia- .tion' 61. the curve ground on the cutter-tooth may be obtained. 7 In this machine, as in the one illustrated-in Figs. 1, 2, and 3;,only one 7 side of each of the-cutter-teeth is'ground;

To grind the other'sides of the teeth, a machine is employed having a converse. ar

rangement-that is, having its slide inclined in an opposite direction to' the slide b t'aud I The principles of construction employed in the grinding-wheel di faced theiotherway. This arrangement would be obtained "by mounting the mechanism located 'onthe front of the,machine,as shown, on thebackof the machine and, conversely, bringing'the'ciitter at the other, end of its spindle.

the machine could be embodied in a machine for grinding the teeth of spur-gears by setting the grinding-wheel with its plane parallel to the axis of the cutter-spindle, and preferably giving either the gear or the grinding-wheel a movement longitudinally of the gear-teeth.

It willbe noted. that the first-described embodiment of; my invention difiers from the second in that the-former grinds, surfaces on the cutter-teeth which are those of a true bevel-gear in which the base-circles of the involutes decrease in diameter as they approach the apex of the gear, whereas, the latter grinds involute surfaces, all portions of which have the, same base circle or cylinder, although the general form of the completed cutter is that of a section of a fluted cone. The rela-.

. tive movement of the .blankand grindingwheel in the latter embodiment is that of a rack and pinion of the spur-gear system havholder, said mechanism having provisions forrelatively moving said wheel and holder in a relation wherein the grinding-wheel generates the curved outlines of gear-teeth on a blank held in the holder;

on hardened toothed blanks,a rotatable grinding-wheel, a blank-holder,xand means for imparting a relative movement to the two in the relation of intermeshing gears. n -3. In a machine for generating gear-teeth 0n hardened toothed blanks, the combination of a grinding-wheel, a blankholder, andme'ans for rolling the blank-holder toward and from the edge of the grindin wheel, to generate the side of a momen 'lank by abrasio'n against the wheel; i v v 4. Ina machine fong'en rat ng gear-teeth on hardened blanks,v the bination of a blank-holder, a' grinding+wheel, and means for imparting a relative movement to the two in the relation of spur system. 4

5. In a machinefor g onhardened blanks, th blank-holder, a grinding toicorrespond to a skewe nerali gig gear-teeth el set an gularly t and means in the relation of intermes ing gea'mof the spursystem.

on hardened toothed blanks,=the combination :of a grinding-wheel having anactingface at right a'ngles'to its axis, a 'blankholder, and means for rolling the blank-holder toward and on hardened toothed blanks, the combination of a grinding-wheel, a blank-holder, "and means for rolling the blank-holder toward and from the edge of the grinding-wheel with its axisfin parallelism at an angle to the axis of the'cutter. v

9. In a machine for generating gear-teeth on hardened toothed blanks, the combination ofa grinder, a blank-holder, a spindle supporting the latter, a bearing for said spindle,

from the grinder, a gear-wheel on said spindle, and mechanism carried by said bearing and engaging the gear-wheel for rotating the spindle in its bearing.

10. In a machine for generating gear-teeth on'hardened toothed blanks, the combination 2. In a machine for generating gear-teeth I intermeshing gears of the for imparting a relative me ement tofthe two 8. In a machine for generating gear-teeth means for rolling said bearing toward and.

ism. forpositively controlling the wheel and mbinatlon of a- 6. In a machine for generating gear-teeth from the edge of the grinding-wheel in a path of a grinder, a blank-holder, a spindle supporting the latter, a bearing for said spindle, means for rolling said bearing toward and from the grinder, a gear-wheel on said spindle, mechanism carried by said bearing and engaging the gear wheel for rotating the spindle in its bearing, a driving member mounted in a stationary bearing, and a flexible and extensible rotary connection between said member and said mechanism.

11. In a machine for generating gear-teeth on hardened toothed blanks, the combination of a grinder, a blank-holder, a spindle supporting the latter, a bearing for said spindle, means for rolling said bearing toward and from the grinder, a gear-wheel on said spindle, mechanism carried by said bearing and engaging the gear wheel for rotating the spindle in its bearing, and means for locking said mechanism.

12. In a machine for generating gear-teeth on hardened toothed blanks, the combination of a grinder, a blank-holder, a spindle supporting the latter, a bearing for said spindle, means for rolling said bearing toward and from the grinder, a gear-wheel on said spindle, mechanism carried by said bearing and engaging the gear-wheel for rotating the spindle in its bearing, a lockin g device carried by said bearing for locking said mechanism, a movable member mounted in a fixed bearing for operating said device, and a flexible and extensible connection between said member and said device.

13. In a machine for generating gear-teeth on hardened toothed blanks, the combination of a grinder, a blank-holder, means for rolling said holder goward and from the grinder, mechanism for :otating the holder on its axis independently of its rolling motion to index the blank, a c' ntinuously-rotating shaft, and a part drive thereby and operating intermittently on said mechanism, for driving the mechanism 14. In a machine for generating gear-teeth on hardened toothed blanks, the combination of a grinder, a blank-holder, means for rolling said holder toward and from the grinder, mechanism for rotating the holder on its axis independently of its rolling motion to index the blank, 2. locking device for locking said mechanism, a continuously-rotated shaft,and a part driven thereby and operating intermittently on said locking device, for actuating the same.

15. In a machine for generating gear-teeth on hardened toothed blanks, the combination of a grinder, a blank-holder, a spindle supporting the same, a bearing therefor, means engaging said bearing for causing axial rotation thereof when lateral movement is imparted to it, a slide carrying said bearing, and means for reciprocating said slide, whereby the blank-holder is caused to roll toward and from the grinder.

16. In a machine for generating gear-teeth on hardened toothed blanks, the combination of a cutter-holder, means for imparting a reciprocating rolling motion thereto, a grindingwheel, a bearing journaling said wheel, and means for adjusting said bearing in the arc of a circle whose center is a point reached by the axis of the cutter-holder in its reciprocation.

17. In a machine for generating gear-teeth on hardened toothed blanks, the combination of a cutter-holder, means for imparting a reciprocatory rolling motion thereto, a grindingwheel, a bearing journaling said wheel, a member supporting said bearing and adjustable in the are of a circle whose center is a point reached by the cutter-holder in its reciprocation, and means for adjusting the bearing on said member to move the wheel radially with respect to said point.

18. In a machine for generating gear-teeth on hardened blanks, the combination of a blank-holder, a grinding-wheel representing a generating gear-tooth, means for imparting a relative movement to said holder and grinding-wheel in the relation of intermeshing gears, and a device for truing the surface of the grinding-wheel, said device being mounted for movement in the generating-surface, and the grinding-wheel being mounted for movement of its generating-face toward said device.

19. In a machine for generating gear-teeth on hardened toothed blanks, the combination of a cutter-holder, a bearing-therefor, means for imparting a lateral reciprocatory movement to said bearing, a member having a connection with said bearing causing it to roll when thus reciprocated, and means for moving said member longitudinally at a predetermined rate during the reciprocation of the bearing.

20. In a machine for generating gear-teeth on hardened toothed blanks, the combination of a cutter-holder, a bearing therefor, means for imparting a lateral reciprocatory movement to said bearing, a member having acounection with said bearing causing it to roll when thus reciprocated, means for moving said member longitudinally at a predetermined rate during the reciprocation of the bearing, and provisions for adjusting said means to vary the rate of movement of said member.

21. In a machine for generating gear-teeth on hardened toothed blanks, the combination of acutter-holder, a bearing therefor, means for imparting a lateral reciprocatory movement to said bearing, a member having a connection with said bearing causing it to roll when thus reciproeated, means for moving said member longitudinally at a predetermined rate during the reciprocation of the bearing, and provisions for reversing said means to produce said movement in the same direction with the movement of the hearing,

or opposite thereto,

22. In a machine for generating'gear-teeth on hardened toothed blanks, the combination of a cutter-holder, a bearing therefor, a slide carrying said bearing, means for reciprocating said slide, a member having a connection with said bearing causing it to roll when thus reciprocated, a lever connected with said member, and a guide on the slide engaged with said lever.

23. In a machine for generating gear-teeth on hardened toothed blanks, the combination of a cutter-holder, a bearing therefor, a slide carrying said bearing, means for reciprocating said slide, a member having a connection member, a guide on the with said bearing causing it to roll when thus reciprocated, a lever connected with said EDWIN R. FELLOWS.

Witnesses:

WILBUR A. LEONARD, E. J. FULLAM.

slide engaged with 15