US1443639A - Relieving machine - Google Patents

Description

Jan., 3o, 1923.

F. MLLER. REUEVING MACHINE, OR|G|NAL FILED MARV 1.19.19 5 SHEETS-SHEET l H QN EN u umm n Jian. 3o, 1923.. 1,443,639

. F. MULLER.

RELIEVING MACHINE. ORIG NAL F1 LED MAR. 3l 1919. 5 SHEETS-SHEET 2 Jan. 30,' 1923.

F. M'LLLER RELIEVING MACHINE ORIGINAL FILED MAR.

5 SHEETS` SHEET 3 www Jan. so, 1923. 1,443639 F MULLER RELIEWNG MACHINE. OmGlNAL FI LED MAR 3l 1919 5\ sHEETs-sHEET 4 Jan. 30. 1923.

srss

FRIEDERICH MLLER, OF HARTFORD, CONNECTICUT, ASSIGNOR '.ll PRATT & WHIT- NEY COMPANY, F NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

RELIEVING MACHINE.

Original application led March 31. 1919, Serial No. 286,524. Divided and this application filed May 13,

To all 707mm may conce/'fn' Be it known that I. Funnix-mou MiLLER, a. citizen of the United States. residing at Hartford. in the county of Hartford and State of Connecticut. have invented certain new and useful Improvements in Relieving Machines, of which the following is a specification.

My invention relates to relieving machines and particularly to relieving machines for .operating on cut-ter blanks having teeth provided with non-radially arranged cutting faces.

One object of my invention is to provide a machine that shall cuta blank to a rectilinear or to a non-rectilinear contour while effecting relieving movements ofthe cutting tool and compensating such relieving' movements'at different blank diameters for the non-radially arranged cutting faces on the teeth of the blank.

Another object of -my invention. is to provide a. machine of the above indicated char acter that shall be'V provided with a pin and a. former for guiding a cutting tool to cut the blank to a redetermined contour, means for effecting re ieving movements of' the tool to relieve the teeth of the blank in conformity either to helical or straight teeth, and means for so varying the relieving' movements as to compensate at different blank diameters for non-radially arranged cutting faces on the teeth of' the blankl A further object of my invention is to feeding movements` between the cutting tool and the blank, means for stopping the blank rotation during' each feeding movement, means for effecting transverse movements of the cutting tool to permit the intermittent feeding movements. means for effecting rclieving movements'of' the tool. and means for varying the `relieving movements to com pensate at different blank diameters` for the non-radial cutting' faces on'the teeth of' the blank.

In the art of cutting many materials and particularly in cutting metals. it is preferable for many classes of' work to incline the face ot' the 'cutting tool backward with respect to the direction of'movemnt thus proprovide a relieving machine with mccha-. nlsm for efi'ectlng intermittent longitudinal' Serial No. 469,267.

viding a rake or undercut which provides a sharper cutting edge and enables other ad vantages t0 be obtained. To a very limited extent this principle has been applied to milling-cutters, theA cutter faces 'being inv clined backward Iwith respect to radial lines, but it has not, heretofore, been deemed possible to cut a milling cutter to different diameters in accordance with a predetermined contour and to effect relieving movements so that the teeth can be ground on the cutting faces Without changing the effective Y 'contour of` the blank. If the cutter is cut t0 more than Ione diameter and the teeth have faces which are undercut oi' non-radially arranged, it essential while cutting the blank to compensate the relieving' operation at the different blank diameters for the non.- radial cutting faces on the teeth.

'lhis application is a division of the ap-t .plication Serial No. 286,521. filed March 31,

eov

specific methods disclosed in this applicav tion are specifically claimed in 'my copending' application Serial'No 323.112, filed Septcmber 11, 1919. The machineA disclosed in this application is adapted to form a cutter such as is described and claimed in my copcnding application Serial No. 323.110 filed September 11. r1919.

'.l`he cutters. which are shaped by the relieving' machine disclosed in this application, are adapted to cut any practical contour. llach cutter blank is cut. to diderent diametersand is adapted to cut eithera rectilinear .or a non-rectilinear contour. The cutting teeth on the blank are either helical non-radially arranged cutting faces. In

case the teeth are helical in for-m, the cut-v lines extending backward and inward t'roin ting tace of each tooth conforms to a heli cold. The helicoid is formed by a gene 'atrix following a helix on a small cylinder concentric with the axis of `the cutter and also following a helix on a much larger cylinder also concentric with the axis. The teeth of the cutter and t-he cutting faces may he inclined in either direction with respect to the axis and the degree of inclinotion may be varied as required.

Each tooth of the cutter is relieved along the outline of the'non-radial cutting lace. The relief lines form a continuous surface or continuons surfaces which extend from end to end of the cutter. The relief lines are properly constructed notwithstanding variationsin radius at. difierent points along the outline ol' the cutter and notwithstanding tli'e variations in angular positions resulting from the non-radial helical ciittiiig.l':ice. Preferably, the relief lines are maintained in'siniilar relationship to each .other as they extend backward and inii'arihtbe lines conforming to spirals ot'- Archimedes.

lVhen the relief lines contorni to spirals and are maintained in similar relationship as they extend backward and inward. as is preferred, it is possible to sharpen or grind the teeth otl the cutter on the ir'ont cutting faces without changing the eli'ective contour. The teeth present the same etlective contour at successive non-radial helicoidal surlfaces of intersection Similar in torni and position to the initial cutting faces. At any surfaceback ot the initial cutting face and similar l to said tace, the saine eti'ective contour will be found. Therefore, it' the teeth arc ground on their front Faces to non-radial .helicoids which are the same as the nonradial helicoids ot' the .initial cutting taccs7 the elllective contour will remain the same.

ln the accompanying drawings:

Figure 1 is a, partial trout elevational View, partially insection, ol :i machine con- `str-acted in accordance with my invention.'

Fig. Qlis a partial plan view of the niachine showing the tool-carrying slides.

Figs. il and 1i are detailed `views ot' the ymechanism for varying the movement ofthey blank carrying spindle. the, views being taken from opposite -sides of the machine. Fig. 5 is an end view ot the machine. `Fig. t3 is transverse vertical sectional View taken along the line l--- of Fig. l.

Fig. T a vertical longitudinal sectional i i'iew of the machine.

Fig. 11 is a transverse vertical sectional View taken along the lilies ll-ll of Figs. 1. i2 and 7.

Fig. 12 is a transverse vertical sectional View taken along the lilies 12-12 ol' Figs. 1. 2 and "T.

Fig. 12% is a tragmeiitar)l longitudinal scctional vie along the. lines l-l 13 of Figs. 2 and 11.

Fig. 1l is a fragmentary transverse sectional view taken along the lines Hwldfkk ol Figs. 3 and 4.

Fig. 15 is a transverse sectional view taken along the lines 15-15 ot' l"ig. 4. v

Fig, 16 is a partial rear view, partially in section. ot the machine.

Figs. 1T. 1S and 15) are diagramiiiatiil views illustrating the operation that is l'ollowed in operating on cutters having nouradiali).` arranged cutting laces.

Fig. 2l) is a fragmentary sectional view .similar in )art to Fie. 11.

Fig. 21 is a development view member shown in Fig. 2o.

Figs. 22. )l and 24 are diagrammatic views showing the relation between the. former members and the blanks for cutters provided with non-radially arranged cutting faces.

llel'erring 1o the drawings. a relieving niacliintl is provided with a main trame or bcd l upon which the other parts of the machine aremountcd. headstock :2 anda tailstock il are provided l'or carrying the blank which is to be operated on. tool holdiugand-op4 eratiug mechai'iism l is provided. as shown in Fig. l. lrelerabliY the hcadsiock 2 and the tailstock Il are so arranged as lo hold the blank against longitudinal movement. the tool mechanism l being moved longitudinally along the blank in the lmanner to be pres` cnlly set l'ortli. ll'hcn the machine is so constructed. tlielicad stock :2 is lixedly sc Cured to the bed. preferably being formed in part integrally therewith. as shown. 'l`lie tailstock 3 is adjustable along thc bed to accommodate blanks or blank arboi's ol dil"- leirxent lengths. y

ihe hcadstock 'l olI thc caui is provided with a rotatable spindle mounted in suitable bearings (i and T. Secured to thc spindle 5. in any suitable manner. is a collet chuck H ,which may be ol' any usual or prcl'errcd form and which is adapted to grip either the shank ot' the. tool to be formed and relieved or an arbor upon which -the ,tool is mounted. As illustrated. there is a blank A mounted upon an arbor l. the arbor being engaged by the chuck H. A drivenicclianism including a driving member in the l'orm ot ay worin wheell) which meshes with a worm l() on a transif'erse rotatable shaft ll. is provided foi rotating the spindle 5.

The tailstock 3 may be of any usual or l preferred construction, and is adjustable v.along waysv 12 and 13. The tailstock 3 can besecured in adjusted position by means ot .',alamp 14 which is controlled by a lever 15. f fhenftailstock vspindle 16, which carries a fnter '17,' can be moved longitudinally by vmeans of-.ascrew 18'under the control of a hand Wheel 19. A handle 20 is prov1ded'for clamping the sleeve inv adjusted position.

shown'in Fig. 2, the center 17 is adjusted in engagement with the end of the 'abor B.

,'.The tool Amechanism 4 includes a carriage a'nd such a tool is preferable for .many

classes of work.v However, the invention is ,',Ilot limited toma non-rotary tool and when `preferred a rotaryltool can be used. The 'tool 25 iSpreerably very narrow, but if desireda wider tool can be used when con- ',s'tructed inaccordance with the method set .forth inmy Patent No. 1,348,302 dated August 3, 1920.

`As stated at the outset, a machine embodying the invention is adapted for cutting va blank having4 a varyingdiameter. rl`he diameter may vary uniformly from end to -end of the'blank, thus providing a uniform taper, or it may vary in any desired wayso as to provide the. blanklwith any predetermined contour differing from a straight line.` The variations in the diameter ot' the blank `are determined by moving the sl'de 24 to'- gether with the tool transversely` and pret'- erably, for regulating and controlling the transverse movements, I provide a former and a former pin, one carried in fixed position on the bed 1, and tlie other carried by the slide 2 4. As illustrated, a former 26 is carried by the bed 1 and a former pin,27 is carried by theslide 24. rl`he former 2G has exactly the same contour with which the blank is to he formed and the former .pin 27 has exactly the same shape the cutting tool 25. The pin is detachably secured to the slide, in a. manner to be hereinafter set forth. so that it can be removed and another pin be substituted correspomling to atool differing in shape trom the tool 25 which is shown. A bracket 28, which is rigidly secured to the bed 1, is provided for supporting the former 2G.' In order to permit adjustment, the former 26 is secured to a slide 29 which is longitudinally movable along a suitable guideway 3() on the bracket. a screw 31 beingr provided tor effecting longitudinal movement. The slide can be locked in ad- "justed position by means-of screws $52. 32 which engage a gib 33. rThe slide 2S) is provided with a T-slot 34 which is adapted to receive -T-bolts -35 passing through the former. Such arrangement is provided to permit the ready adjustment of the former. To Jf'urther assist in holding the former in place and to prevent any possible Jree movement thereof, a hooked bolt 3G is provided which.'when tightened, serves to draw the former back against a suitable shoulder on the slide. ln practice, a former 26 is selected having the contour with which the blank A is to be formed and then by means of the slide 29 the former is adjusted longitudinally until it bears the same relation toy the former p'in 27 that the blank A bears to the tool 25. As the carriage 2l is moved longitudinally the slide 24 with the tool is moved transversely so as to keep the former pin 27 in engagement with the former 26.

ln order that the tool may be given arelieving movement to prope'rly relieve the several teeth on the blank, it is 'not rigidly secured to the slide 24 but is transversely movablev thereon. A slide- 37, which is transversely movable along a suitable guideway, is mounted on the slide 24. A mecha` n'sm, for effecting regular reciprocating relieving movements ofthe slide 37 and the tool in suitable timed relation with the rotative movement ot' the blank vis carried in part by the slide 24. ln order thatl the tool may be adjusted tor blanks of diti'erent sizes7 a tool-carrying slide 38 is provided which is transversely movable on the slide 37. A screw 3S) which is rotatedby means of a hand wheel 4l), is provided for moving the slide 38. The slide 38 is provided with a transverse T-slot 41- and a tool post 42 is held in place by means ot' T-bolts 43 entering the slot 4l. The tool post has a toolrecewing aperture provided with a` horixontal top wall 44 exactly at the level of the axis ot' the blank. 'lhe tool 25 is positioned with its top surface engaging the horizontal wall 44 of they tool post. and is held in this" feeding or inward and outward to follow' the contour.

llO

The relieving mechanism for moving the I lower end is provided with a roller engagf ing the cam 4G. The upper end of the'lever engages an abutment 52 on the slide r.37. A'coil spring 53 is interposed between the slide 37 and the slide 24. this spring tending ,in a bearing to press the slide 37 forward. thus holding: the abutment 52 in firm contact with the upper end ot' the lever 5l. lt .vill be seen that. when the cam 46 is rotated, the lever 5l will be oscillated, thus giving' a re ciprocating movement to the slide 37 and to the tool 25. The shape ofthe cam 46 is such that the slide 37 is moved forward relatively slowly at a uniform rate so that the tool may etl'ect a relievin, r cut. and then drawn back relatively rapidly so as to withdraw the tool and position itJ for another eut.

'l`he cam hlo is driven in timed relation with the blank rotation. as before stated. For rotating the cam. l make use of the aforesaid transverse shaft li. A shaft 54, which is mounted partl'v in the main frame l and partly in a l 'acket 55 secured thereto. is positioned innnediatel)Y below the shaft l1. 'lhetwo shafts 1l and o lare connected b v means of a gear wheel on on the shaftA ll. a gear wheel :'17 on the shaft 5l and an idler gear wheel 5H meshing` with the two xrear wheels 5G. and 57. rl`he idler gear wheel is mount-ed on a bearinzgr sind 59 which is carried b v an adjustable slotted arm (SO. The arm (S0 is carried b v a hub (3l which assists in supporting' the shaft l1. The speed ratio between the two shafts ll and can be changed b v removing' one or both off the gear wheels 5G and 5T and substitut;- in; other gear wheels of different diameters. it being clear that the idler j fear wheel 58 can be adjusted to mesh with such diiferentl'v diameter-ed `'ear wheels. vertical shaft` ('12 is mounted in the bracket 55 and is driven from the shaft 54 by means ofv bevel gearing` ('13. rl`he shaft (v serves to drive a loinfitinliiiallv lsplincd shaft (i5 by means of bevel gearingr (il. rThe shaft is supported partlyv in a bearing on secured to the bed and partly in bearings (37 on a depending bracket (3S secured to the car riage 2l.

worm o9. which isnuounted on the shaft (i5 between the bearings G7, is splined to the shaft. The worm 69 meshes with a worm wheel 70 which is connected with a transverse shaft 7l. The 'worm wheel 7G and the shaft 7l are rotatably mounted in a bearing 72 Aformed in the bracket 68, andI 72 formed on a supplemental bracket T4 secured to the bracket (3S. ii. bevel gear wheel 75 is slidablvY mounted on the shaft 7l and is engaged by a bearing Tt on the aforesaid bracket 5() depending from the front end ot 'the slide The bevel gear wheel 75 and the shaft Tl are connected by means of cani slotsTl formed in the sha ft and pins 75 proiectinj r from the gear wheel into the cam slots so that, the bevel gear wheel is rotated. but is at 'the saine time free to move transversel)v of the machine when the slide 24 is moved. The cam slots 7l' in the shaft 7l are so formed as to compensate the relieving movements .at diil'erentblank diameters for non-radial cuttin r faces. The operation of the pins 75 in the cam slots Tl will be set forth more fully hereinafter. Inasmu'ch as the bevel gear wheels 75 and 77 are both supported by the bracketl 50, they are at all times held in mesh. It will be seen that with this construction power is transmitted from the shaft 1l, through the several parts that have been described, to the shaft 65, and is transmitted from the shaft 65 to `the shaft l? and the cam 46, the connection between the shaft and the shaft 47 being such that tree transverse movements of the cam and associated parts is permitted. The cam lo is given one -complete Yrotation for` cach tooth ot' the blank. The machine ain be adjusted for blanks with different numbers ol teeth b v changing the gear Wheels 56 and 5T. as already explained.

has already been stated. the machine is adapted for cutting blanks having helical teeth. ln order that blanks with such teeth may be proprely relieved, it is necessary to etl'ect the relieving movements of the tool in peculiar relation to 'the rotative movement of the blank so that the relief may be in conformity with the helical teeth. I have stated that the relieving movements of the tool are effected in timed relation to the rotative movement of the blank; and, for any given position of the carriage, this timed relation .is fixed and definite. but when the earriage is moved to bring;r the tool into a new cuttingr position. it. is necessary to vary the relation between the relieving,r movements ot the tool and the rotative movement of the blank. For this purpose I make use of a. mechanism which is in many respects similar to that set fort-h in my aforesaid Patent 1,420,611. however. in that l have so arranged the mechanism that the aforesaid relationship is varied by changing the rotative movementof the blank rather than by changing the relieving movements of the tool. Vhile l prefer to `change the blank rotation, it will be understood that my present invention in its broader aspects is not limited in this respect.

ln the construction illustrated` the driving The present construction differs,"

member or worm wheel 9 is not connected dibearing in the outer end of the spindle 5. A frame 82 is recessed to receive the outer end of the spindle 5 and to engage the outer surface thereof. The aforesaid worm Wheel 9 is rigidly secured to the sleeve 79. A shaft 83 having rack teeth formed thereon at 84 is slidably mounted in the sleeve (9.' T he shaft 83 is splinedto the sleeve9 so as to be -rotatable therewith. A transverse shaft 85 which carries a. pinion 86 meshing with the rack teeth 84, is-rotatably mounted in bearings in the frame 82. A transverse shaft 8T is also rotatably mounted in the frame 82. The two shafts 85 and 8T are connected by spur gear Wheels 88 and 89. 'A third rotatable shaft 90 is rotatably mounted in the frame v82. A Worm 91, Whichmeshes with Worm teeth 92 formed in the periphery of 'the spindle 5` near the end thereof, is secured to the shaft 90. A gearing is provided at the 'side of the bracket 82 opposite from the gears-88 and 89 for connecting the shafts 87 and 90. A gear Wheel 93 is mounted on the. shaft 87, and a gear wheel 94`is mounted on the shaft 90. An adjustable slotted bracket 95 is mounted on the frame 82 and this car# ries adjustable bearing studs 96 and 9T on which are mounted, respectively, idler gear wheels 98 and 99.

An annularly grooved collar100 is carried by the shaft 83 near the outer end thereof. A longitudinal guide stud 101 is rigidly secured to the main frame 1 adjacent the shaft bracket 102 having a fork 103 entering the groove in the collar 100 is slidably mounted on the stud 101. The bracket 102 is apertured to receive a longitudinal rod 104, which is connected at its right-hand end with the carriage 21'. The bracket`102 may be clamped to the rod 104 in any desired relative position and preferabl f by means of screws 105, 105 provided with andles 106.

It will be seen that, when the carriage 21 is moved longitudinally along the bed, the rod 104, together with the bracket' 102, will be moved at the same time and to the same extent. ly reason of the engagement of the fork 103 with the collar 100 the shaft 83 is similarly moved, thus'moving the rack teeth 84. When the rack slides longitudinally the pinion 80 is turned and this serves, by means of the gearing and the several shafts that have been described, to turn the worm 91.

gearingp T8 rotates bodily with the sleeve 79.

lt willfthercfore be clear that the relative movement' of the spindle 5 with respect to the sleeve T9 simply serves t-ocithenincrease or decrease.` thc spindle rotation to a certain extent. However, the relative movement of the spindle 5 is determined by the longitudinal movementof the rack 84, which in turnis determined by the longitudinal movement of the carriage 21 and of the cutting tool 25 carried thereby, lnasmuch as therelieving am 46 reciprocates the tool with a frequency which iS normally uniform, andinasmuch as the spindle 5 and the blank are given a changed rotation which is in exact proportion to the llongitudinal movement of thecarriage and the tool, it is clear that the relieving movements are effected in such relation to the blank as to be in conformity with helical teeth.

The amount of variation of the spindle 5 and blank rotation can be changed in accordance with the degree of inclination of the helical teeth by removing one or the other or both of the gear wheels 493 and 94 and substituting other gear -wheels of dilferent diameters. The idler gear wheels 98 and 99 can be properly adjusted to mesh with such differently diametered gear wheels. It is also possible to cause the relative movements of the spindle 5 to take place in either. direction in conformity .with helical teeth inclined in either direction. -AS illustrated, the machine is adjusted for cutting teeth with left-hand helices. with right-hand helices the idler gear Wheel 98 is removed and the gear Wheel 99 is adjusted to mesh directly withthe gear Wheels 93 and 94. lVhen it is desired tocut a blank with straight teeth instead of helical teeth, the gearing rendered ineffective, as for insta-nce by loosening the clamping screws 105, thus permitting the'rod 104 to slide freely through the bracket 102. By loosening the clamping screws 105 it is possible to preliminarilv adjust thecarriage without affecting the position of the spindle 5 and blank. "hen the cutter and the blank have been properly adj usted relatively, the handles 106 are turned to connect the carriage with the mechanism for controlling the spindle rotation.

From the foregoing description it Will be observed that in followinghelical teeth as described, the blank is rotated in'each instance through a little more or a little less than one revolution, as required for righthand or left-hand helices. lt will further be seen, that during each rotative movement of the spindle 5 and blank a whole number of relieving movements are effected.

1When cutting a blankwith undercut faces. it is necessary to vary the ordinary relation between the relieving movements of the tool andthe rotative movement of the blank as the cutting tool moves inward or outward to'conform to different blank diameters. One way of varying the relation will he understood by reference to the diagrammatic Fig. 1 7. In this view 't may be considered to be a fragmentary sectional view taken at the .maximum radius fr o'f a cutter C having undercut faces. Underthe' F or cutting teeth control of the former and the former pin7 the cutting tool 25 is at a dista-nce fr from the blank axis and is in position to engage the point of the tooth shown and tov cut .the proper reliel2 line al-ci thereon. The tooth section at a smaller radius r is shown at lf. For this radius. without special `provision being made, the tool Q5 would be in the position indicated by dotted lines at the distance r from the blank axis. However, by reason of the inclined cutting Jfaces on the blank. the blank tooth would not be in engagement with the tool but would be separated therefrom by the angle m. The tool, however, would immediately start its inward relieving movement notwithstanding the fact that the blank tooth had not yet reached it, and the result would be the cutting of an incorrect reliet line al-(l. F or a still smaller radius 7" of the blank, as shown at t". the result would he similar except that the point of the tooth would be separated from the tool by a great/er angle m, with the result that the incorrect relief line IWL-(1 would be further from the correct relief line tlv-d.

In order to avoid the errors which would occur, as shown in Fig. '17. l vary the relationship between the relieving movements of the tool and the rotative movement ot the blank in such a way that the tool. as concerns its relieving movements, is always in the same position when engaged by the front edge of the tooth. rllhis will he clear from an inspection of, Figs. 1 8 and 19. Fig. 18 shows -the tool at the sainek radius r from the blank. axis las was shown' in Fig. l?, but the relation of the relieving movement has been so changed that the blank is in position to be engaged by the point ot' the tool when the relieving movement starts. The tooth is therefore cut with the correct relief line rZ-d- Similarly. in Fig. 19. the tool is shown at the same distance r" from the blank axis as was shown in Fig. 1T. but the relation ot' the relieving movement has been so changed that the blank is in position to be engaged by the point of the tool when the etl'ective relieving movement starts. The tooth is therefore cut With the correct relie'll line cil-d. It will be seen that the operation. as illustrated in Figs. 17 to 19, is in no way effected by or dependent on the longitudinal inclination of the cutting faces. ln other words. it is innnaterial whether the cutting faces be helical or straight.

l The required variations in the relationship 'between the relieving movements ot the tool and the rotative movement of the blank can be brought about either by changing (usually advancing) the blank move-y ment or by changing (usually retarding) the tool movements. l have found simpler. to retard thetool movements. and this is particularly desirable when means are provided as herein disclosed for changing the' blank movement to conforilnt helical teeth. The tool movements may be properly retarded by forming the grooves 7l in the shalt 71 in accordance with the degreeof undercut. Referring to Figs. 20 and 2l, the shaft T1 is shown provided with inclined cam ngrooves T1', and the bevel gear wheel 75 is shown provided with pins 75, which are adapted to enter the grooves 71'. F ig. ".21 is a development of` the shaft 71 showing the inclined cam grooves. With the pins 71 in the full line position shown, which corresponds to the radius r, the cam 4G is in position to immediately start the inward relieving movement of the tool. From the description which has been given of the mechanism for driving the relieving cam. it will be recalled that for any given longitudinal position of the tool the cam is ordinarily rotated at a speed exactly in proportion toithe rotative movement of the spindle and blank. When the tool is moved inward to a position corresponding to the' radius r. the normal rotative movement of the cam is retarded by an angular distance n which corresponds to the angle m' shown in Fig. 17. Vllhen the tool moves still further inward to a position corresponding to theradius if", the cam is still further retarded through an angular distance n corresponding to the angle m shown in Fig. 17. The result of this retardingot' the tool is to cause it to be always in the 'same position as concerns its relieving movements when the 'front edge ot the tooth reaches it. The VFact that the blank may not have the maximum radius 'I' is immaterial provided that the bevel gear wheel 75 is made to take the proper positions along the cam shaft 71. lu order that this may. be conveniently brought. about, the former is preferably constructed so to correspond to the radius of thc blank to be cut. lt the cutter C is to haver a maximum radius r, the `former 26 is made with the point of maximum radius'at a distancel r from a given reference line, for instance the center line'of the bolts 35, lt' a cutter D is to be made having a radius '1"'. then the former 2G is made with the point A ol maximum radius at` the distance r from 115 the center line of the bolts. lf a cutter E is to be made having a 'maximum radius r, then the Jformer 26@ is made with its point of maximum radius at the distance r trom y the center line of the bolts. The construc- 12o tion of the formers in the way described in,- sures the location of 'the sliding gear wheel T5 on the shaft Tl at positions corresponding' exactly to the different radii of the blanks. lu the above manner. the pin and groove connection between the sluit't Tl and the gear wheel 'servcs to vary the relieving movement `to compensate igor the non-radial cutting faces on the teeth ot' the blank. ln mv -copending application, Serial No. 469,266,

. above referred to, and in my application Serial No. 323,114, led September 11, 19,19, means are disclosed and claimed for per forming a like function by varyingthe position of the relieving movements.'

A'screw 10T, which engages a nut 108 car ried by a bracket 109 depending from the earriageis provided for movingithe carriage longitudinally aloneA the bed." he screw is supported at its left-hand end in a"bearing 110. which is .formed in a' bracket 111 secured to the bed. A transyerse shaft/llf-which is connected with tlie"`sci'ew 107-by" means of bevel gearing 113, is mounted in the bracket 111. At the front end of the shaft 112 is a hand wheel 114 by means of which the screw maybe turned manually to move the carriage. A. suitable mechanism is provided for moving the carriage automatica-llyto' 'feed the tool from Aone cutting position to another. This v mechanism is preferably adaptedto feed the carriage intermittently. butaitwill be un.

derstood that as concerns certain phases of the invention l do not so limit myself inasmuch as the carriage may be moved continuously it' desired.. A transverse bearing;` pin 115 upon which is rotatably mounteda sleeve 116, is mounted in the bracket 111. "A gear wheel 117, which meshes with a gear wheel 118 on the shaft 112, is looselv mounted on the sleeve 116 near the inner end thereof. ratchet wheel 119,'is connected with the gear wheel 117. (ear teeth 120, which mesh with a gear wheel 121 secured to the shaft' 112. are formed on the sleeve 116 near t-he outer end thereof. A ratchet wheel 122, which is similar to the ratchet wheel 119, is keyed to the sleeve 116. A swinging arm 123 is loosely mounted on the hub of the ratchetwheel 122'.

A link 124,' which is adjustably connected vat its left-hand end with an oscillatingcrank arm 125,` is pivotally connected with the arm ein 123 near the lower end thereof. The crank arm is secured to al transverse rock shaft 126 which is mounted in a bearing 12T and which carries at its rear end a lever 128. A roller 12S), which is positioned to be engaged by a cam 13() on a `longitudinally rotatable shaft 131.l is carried bythe lever 128 near the upper end thereof. A transverse pin 132, which carries two similar ratchets 133 and 134, is mounted on the 'swinging arm 123. 'lhe two ratchets 133 and 134 are adapted respectively to engage the ratchet wheels 119 and 122. i or out of engagement with the corresponding wheel. ner to be presently described, and it will be seen that at each rotation thereof the arm 123 and the crank arm 125 are oscillated.

" -124. the extent of oscillation-of the plate being adjustable by changing the connection between the link and the crank arm: By

Either ratchet can bethrown into The shaft 131 is rotated in the matr.

means of one or the-other 'of the ratchets 133 or 134, one of the ratchet Wheels 119 or 122 is turned through a Asmall angle, thus turningthe shaft 112 land the lead screw 107 and moving the carriage. 1t will be seen that the carriage' movement vis relatively great when the pawl 133 is in use, and is relatively small when the pawl 134 is in use. By selecting the proper ratchet and by adjusting the crank arm connection the desired amount of carriage movementmay be obtained.

Preferably the rotation of the spindle and of the blank is stopped during the feeding movement of the tool. I therefore p'ovide two alternately acting mechanisms, one serving to rotate .the spindle and the blank through one revolution, .or approximately one revolution, and also serving to effect the relieving movements of thetool, and the sol other mechanism serving to effect the longitudinal feeding of the tool and preferably also serving to effect other movements to bei described.

The mechanism for rotating' the spindle and the blank has already been described in part, this mechanism including the transverse shaft 11, the worm 10 and the worm wheel 9. The machine lis provided with a main power shaft 135 .which is adapted to be driven in any suitable way, asfor in stance, by means of a` belt on a pulley 1,36.` A gear wheel 137 is rotatably mounted'on the shaft 135. Thegea'r wheel 137 is connectible to the shaft, 135 by ,means of a splined clutch element 138. The Agear wheel ,137 meshes with a gear wheel 139, which ,isv

lcarries a series of differently diametered gear-S146. rl`he shaft 145 is connected with the aforesaid shaft 11 bymeans-of bevel gearing' 14T. 1The bushiircy 143 'can be moved angularly and longitudinally on the sleeve 142 yso as to bring` the gear wheel 144 into mesh with any one of the differently diametered4 gear wheels 146. A spring-pressed plunger 148, whichis carried by the bnsh' ing 143. is adapted to enter anyone ofd a series of apertures in the sleeve 1421 so as1u to hold the lrear wheel 144 in )roper posi-V tion to mesh with any desiredl one of the gear wheels 146. lt will be seen that by this construction the sh`aft'145 together with the shaft 11 can be drivenfrom the shaft 135 at any one of. a series of speeds.

A shoi't longitudinal shaft 1-19 is moui'ited iii alignment with the main power shaft 135. rI`he shaft 119 carries a clutch element which is adapted to be engaged b v the aforesaid splined clutch element 138 on the shaft 135. then the clutch element is in its right-hand position as viewed in Fig. 16, it drives the gear wheel 137 and the several parts connected therewith. When the clutch element is in its left-hand position it drives the shaft 149. A transverse shaft 15()` which is suitably mounted in bearings in the bed, is connected with the shaft 149 by means of bevel gearing 151. \The shaft 15() car` ries a-worm 152 which meshes with a worm wheel 153 on the aforesaid longitudinal shaft 131.

In the operation of the machine. it is desirable for the sleeve 79 and for the shat't 131 to each make one complete revolution alternatel in succession. 1n order that the desired a ternatemovements of the sleeve and shaft lmay take place, 1 provide automatic mechanism for shifting` the clutch ele` ment 138. The mechanism used is similar in principle to that shown and described in my Patent No. 1,273,903 for driving mechanism, dated July 30th, 1918. The clutch element 138 is provided with an annular groove into which fit rollers or projections on a forked lever y154. The lever 154 is transversely pivoted on the frame and is provided with a rollei 155 by means ot which it may be-moved. A transverse rock shaft 156 is mounted in the traine above the forked lever 154. The rock shalt`156 carries at its rear end an arm 157 in which is mounted aspring-pressed plunger 158. As shown in Fig. 16, the plunger is V- shaped at its lower end and is adapted to engage the roller 155. A lever 159, which is. secured to the rock shaft 156 near the front end thereof, is provided with upper and lower arms. The upper ariii carries a roller 160 which is adapted to be engaged by a cam plate 161. The cam plate 161 is secured to a cani drum 162 which is mounted 0n the sleeve 79. The lower arm of ythe lever 159 carries a i'ollei'163 which is adapted to be engaged by a cani plate 161. The cam plate 164 is secured to a cam drum 165 which is mounted on the shaft 1231.

f hen the parts are in the. positions shown in Figs. 6. 7 and 16 the sleeve 79 is in nio` tion and continues to turn uiitiii the cani plate 161 engages the roller 16() and turns ,the level' 159 in the clockwise direction. as viewed in Fig. 7, or in the counter-clockwise direction, as viewed in Fig'. 16. This movement forces the spring-pressed plunger 158 over the top oil the roller 155 and thus tends to swing the lever 15-1 in the direction t0 shift. the clutch element into position to drive the shaft 149. When the shaft 149 is thus driven, the shaft 131 with the Cam drum 165 thereon is driven in the direction indicated by the arrow in Fig. 6. This movement continues until the cam plate 16-1 engages the roller 163 and swings the lever 169 in the couiitcr-clockwise direction, as viewed in Fig. 7, or in the clockwise direction. as viewed in Fig. 16. other words, ,the cani plate 161 serves to restore the lever to the position which is shown in the drawings. The spring-pressed plunger 158 is again moved over the top of the roller 155 and tends to move the lever 1511 iii the direction to move the clutch elenient 136 into position to drive the gear wheel 137,

Preferably, 1 do not depend solely upon the shifting of the lever 159 for the timing oi the movements oi the clutch element 138. )is illustrated, the lever 154 is provided with opposite fingers 166 and 167 which are adapted to be engaged, respectively, by latches 165l and 169. The latches 168 and 169 are held in engagement with'the fingers by means et a springr member 170. Re- `tei-ring to l `i; r.,16, it will be seen that the latch 168 serves to prevent the movement of the lever 15st toward the left even after the arm 157 has been moved 'to its right-hand position. Similarly, the latch 169 serves to prevent the movement ott' the lever 154 toward the right even after the arm 157 has been moved to its left-hand position. A vertically slidable rod 171, which is normally pressed upward by a springv 172, is provided for releasing the latch 168. The upper end ot' the rod 171 is engaged by an arm 172i which is mounted on :i short transverse rock shaft 174. The rock shaft 174 carries a lever 175 near its frontend. A roller. which is adapted to be engaged by a caiir projection 176,v is mounted on the lever 175. The cam projection 176 is secured to the worm wheel 9. The cani projection 176 is so positioned with respect to the cam plate 161 that the plate first engages the roller 16() and moves [the arm 157 into position to shitt the lever 154. Subsequently, when the spindle 79 has completed the desired revolution. the cam projection 176 engages the roller on the lever 175, thus turning,r the rock shaft and the lever 172B and/moving the iod 171 to release the latch 168. The latch hav,- ing been released, the lever 154 turns under the action of the spring-pressed plunger 158 and disengages the clutch element from the gear 137 and engages it with the shaft 149. The latch 169 is mounted on a short trans verse rock sha'r't 177 which carries a lever 17H near its trout end. A roller, which is mounted near the upper end of the leverl 17H. is positioned to be engaged by a cani projection 17%) on the cam drum 165.' The cam projection 179 is so positioned Withlrespect to'the main cam plate 164 that the plate rst engages the roller 163 and moyes the arm 15811nto position to'shift the lever 154. Subsequently, when the shaft 131 has completed the desired revolution, the cam projection 179 engages the roller and the lever 178, thus turning the rock shaft 177 to release the latch 169. The latch having been released, the lever` 154 turns under the action of the spring-pressed plunger 158 and disengages the clutch element from the shaft 149 and engages it with the gear wheel 137. It will be seen that by means of the mechanism described the spindle-7 9 serves to stop itself after making a complete revolution and to start the shaft 131. Similarly the shaft 131, after making one complete revolution, serves to stop itself and start the spindle 79. Thus these two parts operate alternately in continuous succession.

It is desirable to'feed the tool longitudinally while out of engagement with the blank, that is, when the-tool is opposite the groove between two teeth of the blank. r1-`he blank is therefore preferably mounted in the spindle so that at the position of stopping the tool will be opposite a groove. The grooves are helical but the spindle and the blank are si'ipplementally' turned at each longitudinal movement. This supplemental turning exactly compensates for the inclina tion of the grooves and insures the stopping of the blank with a groove opposite the tool.

Preferably the tool is withdrawn at the time of each longitudinal 'movement, the

former pin also being withdrawn from en' Such wlthgagelaent with the former. drawal is effected by mechanism operated by the shaft 131, the withdrawal being thus properly timed with respect to the feeding movement. An abutment 180, which is engaged by the upper end of a lever 181, is associated with the slide 24s The lever 181 is longitudinall \v pivoted to the carriage 21. rlhc lower end of the lever is providedwith a roller which is adapted to be 'engaged by a cam plate 18;). 'lhe cam plate 182 is mounted on a cani disk 18B which is secured to the shaft 1251. .\t the beginning of the. rotation of the shaft 131 the cam plate 182 engages the roller on the lever 181 and swings it in a connter-clm-kwise direction` thus moving the abutn'ient 18() together with the slide 21 toward the front.. ln this way the tool 25 isa'vitlnlrawn from the blank and the former pin 27- is withdrawn from the erative positions. It will be seen that by thus withdrawing the former pin from the former at the time of longitudinal movement, I avoid an)7 difficulties incident to forcing the former pin along the lformerv while in contact therewith. If the formerpin were maintained in contact with the former at all times difficulty would be experienced in effecting the longitudinal movement. particularly at places where the contour of the former is sharply inclined.

Preferably the former pin is restored to engagement with the former by a- 1elatively slow movement with a minimum of pressure, so that there will be no tendency to 80 bend or distort the pin or to secure uneven contact between the pin and the former. For this purpose, I provide a mechanism for returning the carriage that is entirely independent in its operation from, the'mecha nism for withdrawing it. The before men-A tioned abutment 180 is not connected directly to the slide 21 but is connected to a second slide 18-1 which is transversely movable independently of the first slide 21. Springs 185 are interposed between the slide 184 and the carriage 21 and these .springs tend to. move the slide 184 rearward, thus holding the abutment 180 at all times in engagement with the lever 181.

The two slides 24 and 184 are ordinarily connected by a lock. As'shown most clearly in Figs. 7, 8 and 12, the lock includes a plate 186 .located in a recess in the top of the slide 24. AThe plate is provided with a-boss 109 which projects downward through a. slot in the slide` and threaded into this boss is a Vertical stud 187."The stud 187 extends through and closely fits an aperture in the Slide 184. 'lwo small bell-crank levers 188 areloli pivoted to the slide 181. The levers 188 are provided with horizontal upper arms which engage a collar on the stud 187. 'lhe lower ends of the levers are adapted to be engaged by a tapered cam bushing 189 which is ver- 110 tically movable on the stud. \Vhen the bushing 189 isin itslowerposition, as shown, the levers 188 are forced ont-ward` thus drawing the stud 187 do\vn\\ard and forcing the plate 186 into clamping engagement wththe slide 115 24. ln this way the slide 21 is firmly connected with the slide 184. When the bushing 189 is in its raised positiom'the levers 188 swing inward. thus permitting the stud 187 to move upward and release the plate 186 130v from its clamping engagement with the slide 21. forkedf lever 190` having projections engaging slides or notches in the bushing. I is provided foeanoi'ing the'bushilig 189. The

level' 19t) is secured tout longitudinal rock 125 shaft 191 which -is mounted in bearings `in the carriage :21. A lever 192 is' connected to the lever tilt). The lewer 192 is provided with a roller which is adapted to be engaged by cam plates l9 apd 1% tllatearef'sctlrd 130 to a earn disk 195 mounted on the shat't l?,

It will he seen that as the shait 1?1 rotates.v

the cam plate lfl' engages the roller on the, lever 192. thus moving the lever '19() and the cam hashing 189' upward to release the loelt. Subsequently the roller is engaged hy the cam plate 194. thus moving the am bushing lttl'oownward to re-engage the loelt.

l l have already stated that a supplemental meehanism is provided for returning the slide afterv it has heen withdrawn in the 'manner before deserihed, iret'erahly. in order that the -supplemental turning meehanisni may operate without heing at- 'erled in any way hy the return movement ot the slide 11%. and in order tnrther that. the slide 2l may he returned with a ruiniminn ot' etl'ort. l provide a supplemental means for supporting the slide 'il alter it has heen unlocked from the slide 1&4-, s illust ated, the earriage 2l is provided neel its front and rear with transverse pivot pins 1% and 19T. rl`he earriage is slotted ad jaeenty the pins. and in these slots are posh tioned arms 10H and 19) respeetively pivoted on the. said pins. llhe arms are respeetively provided with rollers 201i and 2111 whieh are adapted to engage the hottom ot the slide 2. The arms are eonneeted hy pivoted linlts 202. and these lin'l-zs in turn are eozmeeted h" a transverse volte 2015. the yoke 202i is provided with slots or notches in whieh lit pivot hosses 21H' projeeting upward from the lever 191i. The result is that when the lever 19() swung upward to release rthe loelt. the arms 198 and 15M) are swung in a eloehwise direction. thus swinging` the rollers 211i) and 201 upward so to lil'ti the slide 2l otl4 from the slide, 1M and support it. indepemlently. The aetual raising o'lu the slide may he hut a few thousandths ot an ineh, toil springs 205 are provided t'or returning, the slide -l rearward as soon as it has heen released h v the loelt and elevated hy the rollers. lret'er- `l ahi): these springs are loeated in long transverse vizylindrieal apertures 206 in the slide i241. rl`he springs ahut at` their rear ends against plugs 20T threaded into the apertures. and at their Vt'ront ends ahnt against heads 20h on transverse rods i205). yl`he rods 2119 extend through eentral openings in the pings 90T and are eonnerted at their rear riadsl wsth lu'aeltets 22.11) on the earrilage Z1.l l reterahly theheads 20H :ire in the torni ol pistons and the forward yparts ot' the 'apertues 20h eoustilute eylinders 211 in whieh the heads Elin lit and move. .t eastino 212. whieh provided with a` transverse pas ageway 213, is seeured to the slide 2l. rl`he passageway lill eouununieates at is ends with eylinders all... i'luid reservoir 2li is also Jformed in the easting 21;). .t resti'ieted aperture whieh is prel'erahly eontrolled hy an adjustahle needle valve 21h. leads trom the passageway 211 into the reservoir Hueh tendeuijv. however. is resisted h v the engagement ot the pistons 20S with the liquid in the eylinders. This engagement Vl'orees the liquid out o'l' the eylinders into the passageway J1-"l and thenee into the reservoir .lll through the restrieted aperture 215. 'the liquid ran pass through this aperture Vonly' relativelv slowly. and thus the return niovenient oti the slide is made to take plaee very slowly, When the slide is moved duieltly forward at the time o1' next leerling. the herir valvey :21T opens to permit the liquid to flow Atrom the reservoir ,il haek to the passageway i213 and the eylinders 211. The

slow return movement eauses the tormer pin to enf ige the former gently and with a minimum loree. so that there is little or no tend-v eney to hend or delleet the parts.

It, will he noted that the several eams 131), ltlQ. 11)?) and 194 are so positioned in relation to each other that the operations whieh they respeetively eontrol take plaee in the tollowing order. First the two slides 181 and :2l are moved haeltward in unison, they' being still vloeked toeether. Then the slide 2l is unloelted Troni the slide '1H-1 and is at the same time elevated on the, rollers 2li() and 201. At or ahout the same time the. carriage is moved longitudinally to teed the tool to a new eutting position. rthen the slide 181 is permitted to return to its normal position. ln the mean time the slide 241 is heing moved slowly rearward under the control of the springs Q05 and the iluid regulating meehanism. After the eompletion o'l the return movement ot the. slide 2l, the rollers 2li() and 201 are lowered and the slide is again loi-lied lo the .slide 134,

l provide a lever 2lb. whieh 'is seeured to the roelt shal't` lill. tor manually releasing the slide 2l ll'rom the slide Inl. wreneh 21h".y as shown in Fig. n. is provided tor moving the lever 21H..` ltwill he seen that the operator. hy moving the lever 21H. ean tnrn the roel; sha1't. thus raising the ram sleevo'lHS) and releasing the` Voelt. segmental gear Q11), whieh is pivoted to the, earriage and meshes with a raelt 21) seeured to they slide. is provided l'or manually moving thel slide il torward. hand lever 221 is eonneeled with the segmental gear 211). It will he seen that hy lowering or `aising the handle the slide 'I1-lean he moved forward or hael-:ward as desired.

lt is heliev'ed that the general operation l in succession.

sired contour and. in the case of an undercut cutter, having the desired relation to the cutter radius, as already explained, blank is put in place. this blank having been previously grooved and roughed out in any usual or preferred manner. 'l`he gearing T8 is adjusted in accordance with the degree otinclination ot the helical tceth on the blank and the gearing .G6-57 is adjusted in accordance with the number ot teeth on' the blank. By means ol the hand wheels` -lfll and ll-l, the tool is adjusted transversely and longitudinally into engagement with the blank at the right-hand end thereof. 'l`hen the machine is started, thespindle TS) Vand the operating shaft 131 operating alternately During the rotative movement of the lblank relieving movements of the tool are effected as described, thus cutting the desired relief on the teeth of the blank. After one complete revolution of the blank the rotative movement of the spindle is stopped and also the relieving movements of the tool, l The carriage is then fed longitudinally toward the lleft, the blank turning slightly in conformity with the helical teeth.

. Just prior to the longitudinal movement the tool slide is withdrawn, thus withdrawing the tool from the blank and the former pin from the former. After the longitudinal movement, the tool slide is moved slowly in the opposite direction, thus gently returning the former pin to the iormer which isv engaged at a. new position. The tool assumes a corresponding position with respect to the blank. After this movement of the tool and formerpin the blank is again rotated through one revolution and these movements are repeated alternately in succession until the blank is completely formed.l The relieving movements ofthe tool are changed in accordance with changes in diameter already described, to compensate for the non-radial cutting faces on the teeth of the blank.

Modifications in the machine and in the arrangement and location of parts'may be made within the spiritI and scope ot my invention, and such modifications are intended to be covered by the appended claims.

What I claim is: I

I.`In a relieving machine yfor operating on a blank having teeth provided with nonradially arranged cutting faces', the combination compri-sing a cutting tool,` means for effecting feeding movements between said tool and the blank, means for efecting relieving movements 'of the tool, and means for varying the relieving movements at dif- `:ferent blank diameters .to compensate for thenonradial tooth faces on the blank.

2. ln a relieving machine for operating on a blank having teeth provided with nonradiallv arranged cutting faces.the combination comprising a cutting tool, means i'or operating said tool to torni a cutter adapted to cut a predetermined non-rectilineal' contour.

means tor effecting relieving movements of' said tool` and means for vanving the relieving movements at different blanl: diameters to compensate for, the non-radial cutting faces on the teeth ot' the blank.

3. ln a relieving machine for operating on a blank having helical teeth provided with non-radially arranged cutting faces, the combination comprising a cutting tool, means for effecting feeding movements between said tool and the blank. means fdr effecting relievingmovements ol the tool, and means tor automatically vaiving the relieving movements at ditlerent blank diameters to compensate for the non-radial cutting faces on the blahk.

4. ln a relieving machine for operating on a blank having lhelical teeth provided with non-radially arranged cutting faces,l the combination con'iprising a .cutting tool; means for operating said tool to `form a cutter adapted to cut .a predetermined nonrectilinear contour, means for effecting re` lieving movements of said tool, and means for varying the relieving movements at dilferent blank diameters to compensate for the non-radial cutting faces on the teeth of the blank.

5. In a relieving machine for operating on a blank having undercut teeth, the combination comprising a cutting tool, means for operating said tool to cut a` predetermined contour, means for effecting relieving movements of the tool, and means for automatically var vingthe relieving movements at -difi'erent blank diameters to compensate for the undercut teeth.

t5. In a relieving machine for operating on a blank having undercut helical teeth, the combination i means for effecting feeding movements becomprising a cutting tool,

tween the tool and the blank to cut the latter to different diameters, means forketi'ecting relieving movements ofi' the tool, arid. meansy torvarying the relieving movemenbat diftere'nt blank diameters to compensate for the undercut teeth.

7. In a relievingmachine for operating lon.

a blank lhaving teeth provided with nonradially arranged cutting faces, the combination comprising a cutting tool, means for' ei"- fecting feeding movements between the oo-l and the blank,l means for guiding the cutting tool to cut a for effecting relieving movements ofthe .tool relative to the blank, andv means for varymg blank diameters to compensate tortille nonradial cutting vfaces `von the teeth.

predetermined contour, meansv the relieving movements atfditferent s. ln a reiieving machine for opeiatingf` on a blank having teeth provided with nonradially arranged cutting faces. the com bination comprising a cutting tool, automatically operating means for governing said tool to for a cutter adapted to cnt a predetermined contour` means for effecting relieving movements of the tool in conformity to the teeth on the blank. and means tor varying such relieving moveiiientsvat different blank diameters to compensate for the non-radial cutting faces on the teeth.

t), lii a relieving machine for opeiatii'ig on a blank having helical teeth provided with non-radially arranged cutting faces. the combination comprising a cutting tool,

means toi' eti'ectiiig feeding movementsl lietivcen said tool and the blank. automatically operating means for ell'ecting relieving movements of the tool iii conformity with tlie helical teeth ou the blank, and means for varying the relievingr movements at ditterent blank diameters to connensate for the nonradial cutting faces .'.i the teeth of the blank.

lll. ln a relieving machine for operating ou a blank having helical teeth provided with non-radially arranged cutting faces, the combination coinprising a cutting tool. automatically operating means for etlfecting feeding movements between said tool and the blank to form a cutter with a predeten mined contour (littering from a straight line. means for effecting relieving movements of the tool in conformity with the helical teeth ou the blank. and means for varying the relieving movements at di'tterent blank dia'iieters in conformity with the nonradial cutting faces on the teeth.

l1. ln a relieving machine for operating on a blank having teeth provided with nonradially arranged cutting faces. the conibination with a cutting tool and means for feeding the tool relatively to the blank, ot means for ettecting an oscillatory transverse movement of the cutting tool to obtain a relieving cut, and means for so moi'lifying' the oscillatory movement at ditferent blank diameters as to compensate for the. nonradial tooth faces on the blank.

l2. ln a ielieving iiiacliiue for operating on a blank havingteeth provided with nonradially arranged cutting'faces, the combination with a cutting tool and means for intermittently and longitudinally feeding the tool relatively to the blank, of

means for effecting an oscillatory transverse movement of the cutting tool to obtain a relieving cut` and means for so n'iiidifying the oscillatory movement at ditierent blank diameters as io compensate for the non-ra dial tooth faces on the blank. l

13. ln a relieving machine for operating on a blank having helical teeth provided with non-radially arranged cutting faces,

l-l. In a relieving machine for operating on a blank having teeth provided with nonradially arranged cutting faces. the combination with a cutting tool. means for intermittently and longitudinally tool relatively to the blank. and means for withdrawing the tool from engagement with the blank prior to each feeding movement and for restoring the tool into operative position relative to the blank after each feedingmovement. of means for ett'ecting an oscillatory transverse movement of-the cutting tool to obtain a relieving cnt and means for so modifying the oscillatory movement at ditl'erent blank diameters as to compensate for the non-radial tooth faces on the blank. i

l5. ln a. relieving machine for operating on a blank having teeth provided with nonradially arranged cutting` faces. the combination with a cutting tool. means for intermittently and longitudinally feeding the tool relatively to the blank. and means for4 effecting transverse movement of the tool to permitthe feeding movements, ot' means for cti'ecting an oscillatory transverse movement of the cutting tool to obtain a relieving cut and means for modifying the oscillatory movement at different blank diameters to compensate for the non-radial tooth faces on the blank.

lo. In a relieving 0n a blank having;- with non-adially arranged cutting faces, the combination with a cutting` tool, means for intermittently and longitudinally.feeding the tool relatively yto the blank,v and means for withdrawing the tool from en` gagement with the blank prior to each feeding movement and for restoring the tool machine for operating into operative position relative to the blank4 after each feeding movement, of means for ettecting oscillating transverse movement of the cutting tool to obtain a relieving cut in conformity to the helical teeth, and means for modifying the oscillatory movement at different blank diameters. to compensate for the non-radial tooth faces on the blank.

1T. In a relieving machine for operating.-

on a blankhaving helical teeth provided with non-radially arranged cutting vfaces, the combination with a. cuttlng toohmeans for intermittently and longitudinally-feed-' mg the tool relatively to the blank, and,I

means for effecting transverse movement ot feeding the vhelical teeth provided v the tool to permit the feeding movements. of means for effecting an oscilli'itorjY transverse movement ofthe cutting `tool to obtain a relieving cut in conformity to the helical teeth, and means for modifying the oscillatory movement at different blank diameters to compensate for the non-radial tooth faces on the blank.

18. In a relieving machine for operating on a blank having .teeth provided with nonradially arranged cutting faces, the combination comprising a cutting'` tool. means for effecting fee-ding movements between the tool and the blank. means comprising a pin and a former for guiding the cutting tool to cut a predetermined cmtourfmeans for varying the movements of the cutting tool to relieve the teeth on the blank. and means for varying the relieving movements at different blank diameters to compensate for the non-radial cutting faces on the teeth. i

lii. ln a relieving machine, :the combination comprising a rotatable spindle adapted to carry a blank having teeth provided with non-rzulially arranged cutting faces, a cutting tool. means for eecting relative feedingr movement between the tool and the blank longitudinally of the latter, means comprising a pin and former for moving the tool inward or outward during the feed# ing movement to cut the blank with 'different diameters. means for effecting relieving movements of the tool in timed relation to the blank rotation, and means for varying the relieving movements of the tool at different blank diameters in conformity Wit the non-radial tooth faces on the blank.

2u. In a relieving machine for operating on a blank having helical teeth provided with non-radially arranged cutting faces, the combination comprising a cutting tool, means for effecting longitudinal feeding movements between said tool and the blank,l

means comprising a pin and a former for guiding the tool to cut a predetermined nonrectilinear contour, means forvarying the movements of the cutting tool to relieve the teeth on the blank, and means comprising a cam member for varying the relieving movements at different blank diameters to compensate for the non-radial cutting faces on the 'teetli.

21. ln a relievingmachine. the-combination comprising a rotatable spindle adapted to 'carry a blank having helical` teeth provided withnon-radially arranged cutting faces. a cutting tool, means foreffecting relative feeding movement between the tool and the blank longitudinally of the latter, means comprising a pin and former for moving the tool inward and outward during the feeding movement to cut the blank with different diameters, means for effectingrelieving movements of the tool in timed relation to the blank rotation. means for varying the relation between the relieving' movements of the tool and the rotative movement of the blank in conformity with helical teeth on the blank. and means for viii-ying the relieving movements of the tool at different blank diameters in conformity with the nonradil tooth faces on the blank.

In a relieving machine, the combinanation comprising a rotatable spindle adapted to carry a blank having teeth provided with non-radially arranged cutting faces, a

carriage movable longitudinal-ly of the spindle axis. atransversely movable slide on said carriage, a cutting tool carried by the slide, mechanism for moving the slide and the 'tool transversely as the carriage moves longitudinally so to cut the blank with a predetermined contour, mechanism for effecting relieving movements of the tool relatively to the slide in timed relation to the blank' rotation. said Amechanism serving to accurately time the relieving movements not-,j

withstanding the inward or outward niove" relative to the blank to 4permit the longi-l tudinal feeding movements, means comprising a pin and a former for guiding the cutting tool to` -cut a predetermined contour, means forV effecting relieving movements,

and means for varying the relieving Inove-l ments at different blank diameters to com pensate for the non-radial cutting faces on the teeth.

24. In a 'relieving machine for operating on a blank having helical teeth provided with nonaadially arranged cutting faces, the combination comprising a cutting tool, means for effecting longitudinal feeding movements between the tool and the blank, means for varying the transverse position of the tool relative to the blank to permit the loiwitudinal feeding operation, means comprising a pin and a foimer for guiding the cutting tool to cut a predetermined 'contoiir, means for effecting relieving movements of the tool relative to the blank. and means for varying the relieving movements at different blank diameters to compensate for the non-radial cutting faces on the teeth.

25. In a relieving machine for operating on a blank havingteetb provided with nonradially arranged cutting faces. the combination comprising a cutting tool, means for effecting intermittent feedingr movements' l on a blank having' teeth provided with non- 'adially arranged enttintr laees. the 'eombination comprising' a vatting tool. means t'or"Y effecting.T intermittent longitudinal feeding' movements between the tool and the blank. means 'for .vithda'awintr the tool fromengagei'nent with the blank prior to eaeb reed ing movement and for restoring' the tool into operative position irelativlv to the blank after each feeding movement. a pin and a former member tor guiding the tool to eut a rn'edetermined eontour. means for effecting relieving' movementsl ol' the tool relative to the blank. and means lor var ving the relievingY movements to rompensate toi' the inni-radial cutting tares on the teeth.

2T, ln a relieving machine 'l'or operating' on a blank having heiieal teeth provided with non-ra liadlj.v arranged rotting' t'aees. the Combination romprisingg a euttingf tool. means for ritter-ting intermittent longitudb nal teeding' movements between .said tool and,v

thefblank. means 'lor withdrawing the tool trom. engagement with the blank prior to earh teei'lingf movement and t'o' restoring' the tool into operative position relative to the blank. means eomprising a pin and a lormer tor guiding the tool to ent a predetermined Contour. means tor etl'ertin} r relievinjg movements ot'.tlie tool in eonl'ormitv with the hyelieal teeth on the blank` and means tur var viug1r the relieving' movements at ditlerent blank diameters to compensate for the non-radial entingl' t'aees 'on the teeth.

"2H, ln a relieving machine l'or operating' on a blank having' teeth provided n'ith non radiallj.' arranged vatting' Jfares. the eombi nation.eomprisiug a enttiin; tool. means 'l'or eti'erting intermittent longitudinal feeding movementsv between the tool and the blaruk.

.means tor varying' the transverse position of the tool relativi 'to the-blank to permit the longitudinal 'feeding' movements. means romprising' a pin and a formel" for guiding the Hitting lool to rut a preilelermined rontour. means l'or ell'ertingl relieving movements. and means lor var'vintg' the relieving movements,at'dil'lerent blank diameters to' rompensate t'or the noiii'znlial enttingr 'tai-es on the teeth ot the blank. i

2). ln a relieving marhine for operatiirgg on a blank having..y helieal teeth provided with, non-radially arranged euttingg' t'af'es. the Combination t'omprisingn a entting tool.

mains for e looting intermittent longitnninal feeding movements between Said tooland the blank. means eonrprisnrg'a pin and a. torner tor raiding the tool to ent a predetermined eontonr. means for varving the movements 'otI the cutting.' tool to relieve the teeth on 'the blank. and means for varying the relieving movements to eoxnpenaate for the non-radial ruttine' tates on the teeth in aeeordanee 'ivith the variations in diameter ol the blank.

Slt). ln a relieving machine tor operating on ya blank having he i"al teeth Y-pren'ided with non-radially arranged cutting r'aces. the f'ombination eomprising.r a cutting' tool. means tor eleeting' intermittent longitudinal 'feeding movements between said tool and the blank` means rompt-ising:- a pin and a 'former for guiding' the tool to eut a predetermined non-reetilinear rontour. means fuor varying' the movements of the cutting: tool to relieve the teeth on the blank. and means lor vanvinp; the relieving' movements to eompensate tor tbe nou- 'adial rotting faves on the teeth in aeeordaure with/the variations in diameter of the blank. 1

Ill. ln a relieving maehine for bperatingf on a blank havingY helir'al teethV provided 'with non-radiallj,Y arranged ruttinglv fares. the eombinatiou comprising a rutting tool, means 'tor elieeting intermittent longitudinal feeding movements between the tool and the blank. means lor var ving; the transverse position ot the tool relative to the blank to permit the longitudinal teeding' movements.. means romprising' a pin and a lormor tor guiding' the rntting tool to ent a predetermined non-reetilinear eontonr` meansfor etl'erting' relievingA movements. and means for varving ther relieving movements to eompens-tate at dill'erent blau-k diameters l'or the non-radial vatting' fares ou the teeth.

52. ln a. relieving; maehine Afor operating on a blank having' heliral teeth provided with nonlrznliallv arranged eutting' fares..

the rombiuation eomprising' a ('uttingf tool` means 'tor ell'ertiugj intermittent longitudi nal feeding' movements between said tool and `the blank. means tor \vitlnlra\vin;' the tool t'rom engagement with the blank prior to earh leerling; 'movement and tor restoring the tool into operative position relative to the blank. means eomprising a pin and a lor-mer los' guiding the tool to vn a prede4 terminrd non-rettilinear eonlour. means tor ell'erting relieving' movements ol' the tool in eontorinitj: with the h eliral teeth on the blank. and `means for varying the relkn'inglA movements at dill'erent blank diameters to .rompensate tor the non-rmlial ru'ttinrr fares means for effecting longitudinal feeding movements between the tool' and the blank, means for varying the transverse position of tlieinoll relative to the blank to permit the longitudinal feeding movements, means comprising-"zil pin and a former for guiding the cutting `tool to cut a predetermined contour, means for effecting relieving'move ments, and means for/varying the relieving movements at different blank diameters in accordance with the contour of the former to compensate for the non-radial Acutting faces on the teeth.

34. In a relieving machine for operating on a blank having helical teeth piovided with non-radially arranged cutting' faces, the combiiiat-ion comprising a cutting tool,

' means for effecting longitudinal feeding movements between the tool and the blank, means for varying the transverse position of t-he tool relative to the blank to permit the longitudinal feeding movements, means comprising a pin and a former for guiding the cutting tool to cut a predetermined noiirectilinear contour, means for effecting relieving movements, and means for varying the relieving movements in accordance with the contour of the former to compensate for the' non-radialI cutting faces on the teeth. i 35. In a relieving machine for operating on a blank having teeth provided with nonradially arranged cutting faces, the combi-v nation comprising a cutting tool, means for effecting intermittent longitudinal feeding lmovement of the cutting tool relative to the cutter blank, means for withdrawing the tool from engagement withthe blank prior to each feeding movement and for restoring the-tool into operative position relative to the blank after each feeding movement, means for effecting an oscillatory transverse movement of the cutting tool-to obtain a relieving cut, and means comprising a pin and am groove connection for so modifying the. oscillatory, movement of the tool as to compensate for the non-radial tooth faces on the blank.

36. In a relieving machine for operating on a blank having helical teeth provided with non-radially arranged cutting faces, the combination comprising a cutting'tool, means for effecting intermittent longitudinal feeding movement of the cutting tool relative to the cutter blank, means for withdrawing `the ltool from engagement with the blank prior to each feeding movement and for re- I'storing the tool into operative position relative to the blank after each feeding movenient, ineans'for effecting relieving movements of the toolin conforniityto the helical teeth on the blank, and means comprising a pin and-groove connection' for so modifying lthe relieving movement. of thetool as to compensate for the non-radial toth faces on the blank.

3T. ln a relieving machine for operating on a blank having helical teeth provided with non-radially arranged cutting faces, the combination with a cutting tool, and means for effecting intermittent loiigitiidinal feeding movementof the cutting tool relative to the blank, of means for withdrawing the tool from engagement with the blank prior to each feeding movement and for restoring the tool into operative position therewith after each feeding operation,-

means for effecting relieving movements, andmeans comprising a shaft having camgiooves formed therein for so varying the relieving movements as `to compensate for the noii-radial cutting faces on -the blank.

438. In a relieving machine for operating on a. blank having helical teethprovided with non-radiali)r arranged cutting faces, the combination with a cutting tool, and means for effecting intermittent longitudinal feeding movements of the cutting tool relative to the blank of means for withdrawing the tool from engagen'ient with the blank, of means comprising a relieving cammember driven. by a ti'aiisversely-mounted cam shaft for effecting relieving movements of the tool relativelyto the blank in confoiniity to the teeth on'the blank While compensating .such movements for the non' radial cutting faceson the teeth of the blank.

40. In a relieving machine. the combination with a rotatable spindle adapted to, carry a blank having helical teeth provided with non-radially .arranged cutting faces, a cutting tool, and means for effecting feeding movements ietween the tool and the'.

blank` of means comprising a relieving cam member driven by a transvcrsely-mounted cam shaft for effecting relieving,movements of the tool in conformity to the helical teeth on thc blank and for compensating such movements in accordance with the non-i'ai dial cutting races on the blank.

41. ln a relieving machine, the combination with la rotatable spindle adapted tocarry a blank having teeth providedwith Inon-radially arranged cutting faces, a cuit-i' relatively to the blank, and means for effectingtransverse movements of the tool to iso

Images