US1913486A - Gear cutter - Google Patents

Description

E. c. HEAD 1,913,486

GEAR CUTTER June 1 3, 1933.

' 4 Sheets-Sheet 1 Filed June 8, 1929 HEB-Mil @im unnuluwnupuunnnmmmg INVENTOR 5547662 C {7921 June 1933. E. c. HEAD 1,913,486

GEAR CUTTER Filed June 8, 1929 4 Sheets-Sheet 2 0 61 Alllllllllll JO 8 z IA a:

'4 'INVENTOR his \ATTORNE Jime 13, 1933. E. c. HEAD 1,913,436

GEAR CUTTER Filed June 8, 1929 4 Sheets-Sheet s E j a 1m mu z 73 1 5 170 169 W INVENTOR 16,0 fig Z 17641 I i L, v hSATTQRNEYj June 13, 1933. E, c. HEAD 1,913,486

GEAR CUTTER Filed June 8. 1929 4 Sheets-Sheet 4 Zz's ATTORNEY/7WL/ 7 "3o cutter constructed according Patented June 13, 1233 UNITED STATE J A TENT OFFICE v nnunsr 0.

HEAD Fnocnnsrnn, NEW Yonx; nssreuon To GLEASON wag-"K510? H E N YORK- AcCORPORATIO N ounnw YORK Application filed June s, 1929'. Serial Ira-369,289.

" The present invention relatestogear cut ters andparticularly to gear cutters of the face mill type such as are used in the cuttmg of spiral bevel and hypoid gears.

The present invention hasfor its primary purpose to make it .possibleto obtain an ex- 7 tremely accurate cutter. Other ob ects of the invention aretoprovide va construction which sgconvenlent for adjustment and .10 which permits the blades to betrued up on thecutter head quickly. Still other obJects of the invention :Wlll be apparent hereinafter V ment ofthe invention;

, Figure 2 1s a section on: theline22 of Figure 1;

Figure 3 is a plan view of a modified form ofcutter; v V v 7 Figured is a section'through this cutter taken on the line HOfFigure 3; Figure '5 is a sectional view on an enlarged scale taken onthe line 5-5 of F igure3; v 'Figure 6 is a fragmentary'plan view of a to another modification of this invention; Figure '7 is a se ,tional view taken on the line'77 of Figure 6; 1 Figure 8 is afragmentary plan .view of still another modificationjof this invention;

' Figure 9 is a section taken on the line.99 of Figure 8; f I H j Figure, 10 is a fragmentaryi sectional view taken radially of avcutter constructed according :to a further modification of this invention;

, Figure 11 is asectional view of the same cutter taken at right angles to Figure 10 Figure 12 is-a fragmentary plan view ofa cutter constructed according to another modification ofthis invention; a, a

Figure 13 is a section through this cutter taken on the line 13-13 of Figure 12.;

' Figure 14 is a section taken on the line 1414of Figure 12;

; Figure 15 is a section on the line15l-15of Figure 17;

Figure 16 is alfragmentary plan View of a cutter constructed according to'a still furthermodification of this invention;-

Figure 17 is a sectional view ofthis cutter taken on the line 17-17 of Figure16; j

Figure 18 isa corresponding sectional View taken radially oii'a' cutter constructed a'ccording to a still further modification of this invention; I r, r I Figure 19 is a fragmentary. plan view of a cutter constructed according to another embodiment of this invention; Figure 20 is a sectional View on an enlarged scale taken on the line 202O of Figure 19;

Figure 21 is a section on the line 21 -21 of Figure 19;

"Figure 22 IS? a fragmentary sectional view of a still further modification of this invention; I I v. I

- Figure 23 is a" sectional view on. an en.-

larged scale taken on the line 23-23. of

Fi ure 22.; and r V g igure 24, is a. section taken on the line 175' ,24245 .of Figure 22; v

I Referring first tothe form shownin ures '1 and 2, 30 designates the cutter head.

This head is provided with a plurality of equi-spaced radial slots in which are adjust- 30 I} ably mounted the blocks 31 which serve to 'carry the cutting blades 32. The blades 32 have acutting portion 33 and a body portion 34. The cutting portion 33 extends beyond the blocks 31 and the adjacent sideface of the 35 cutter head in the direction of the axis of the cutter head; The cutting portions 33 are formed in the usual or any suitable manner being relieved at the tip and on the sides back 7 of the cutting edge or edges. r In the: drawings; all of the blades 32 are inside blades, that is, areprOvided with inside cutting edges.

It is to b'eounderstood; however, thatalternate blades might be provided withvoutside cutting edges or each blade might be formed so as to have both inside and outside cutting j I edges, 1 a I ,7 The body portion 34 of the blade is in the form of a cylindrical stud integral with the cut-tingportion 33, and is ofreducedsiz'e to 0" provide a shoulder 35 between the cutting portion 33 and the stud 3 1. The shoulder 35 is preferably made circular in shape and fits into a correspondingly shaped recess formed in the upper face of the block 31 while the stud 34 passes through a hole formed in the block. Each blade 33 is held in position in its block by a nut 36 that threadsonto the lower end of the stud 34 and serves to draw the shoulder 35 down firmly into its recess in the block 31.

The blade 32 is very simple to make and because of the shape of the stud 3 1 and shoulder 35 can be adjusted angularly on its block 31 to permit using the cutter in an intermittent indexing process as is the cutter of the patent to James E. Gleason, No. 1,236,834 of August 14, 1917,0r in a continuous indexing process, as is' the cutter of the patent to James E. Gleason No. 1,219,378 of December 11, 1917.

Theblocks 31 may be adjusted radially on the cutter head by means of screws 10, only one of which is shown in Figure 1. These screws 410 thread into the cutter head alongside of the blocks 31 and'the heads 41 of the screws engage in kerfs or recesses 42 formed in the sides of the blocks 31. As shown in Figure 1, it is preferable to provide each block .31 with two kerfs or recesses 12 so as to permit interchangeable manufacture and enable each block 31 to carry either an outside or an inside cutting blade. The blocks 31 are secured in any adjusted position by means of the bolts 13, and washers 44:, the stems of the bolts passing through slots 15 formed in the blocks 31 and threading into the cutter head and the heads of the bolts'beingreceivedin countersunk slots 46 formed in the blocks 31.

The cutter head 30 can be secured to the cutter spindle 48 by means of a bolt 19.

Theblades of face mill gear cutter are'relieved on grinding machines built especially .for that purpose and the greatest care is eXercised to insure that the proper pressure angle will be ground on the relieved blades. Difficuity is sometimes experienced, however, in setting up the blades in the cutter head in positioning the blades so that the correct pressure angle will be maintained in the assembled cutter. Figures 3 to 5 represent a form of this invention which is preferred over that shown in Figures 1 and 2 because it eliminates substantially all possibilities of error creeping in in the setting or adjustment of the cutting blades in the cutter head. It is compara tively easy to grind fiat surfaces so that they match each other'and in the form. of the invention shown in Figures 3 to 5 inclusive, advantage is taken of this; The cutter head is ground so that one of its side faces is flat and the blade is so shaped and ground that it has a flat base surface adapted to rest against the flat side face of the head with the consequence that a cutting blade which has been ground to a predetermined pressure angle on the relievadjustment on the cutter ing grinder will not betilted when positioned on the cutter head and the finished cutter will have the true pressure angle.

The cutter head 50 which may be provided with a peripheral ring or shoulder 51 has one side face 52 ground absolutely plane or flat. A plurality of radial grooves 53 are formed in this side face of the cutter head and radial slots 54 are cut transversely through the head to communicate with the grooves 53. The cutter blades 55 have a cutting portion 56 and a foptor supporting portion 5'? integral therewit The cutting portions of the blades may be of any usual or suitable construction. The cutter shown in Figures 3 to '5 inclusive is of the face mill hobbingtype and'the blades are formed according to the principles described in Patent N 0. 1,249,378 above mentioned. The blades 55 shown are adapted to cut alternately on opposite sides of the teeth.

The bottom or inside face 58 of the supporting portion 57 of each blade is ground so as to provide an absolutely plane or flat sur-- face adaptedto rest on the plane side face '52 of the cutter head and this supporting portion 57 is formed with a tongue 59 which is adapt ed to engage in the grooves 53 formed in the cutter head to guide the blade 55 inits radial head. i

Inthe form shown in FiguresS to 5 inclusive, the blades are adjusted by screws 60 which are provided with heads 61' that engage in kerfs or recesses formed in the undersides of the tongues 59 of the blades and which thread each into another screw 62 which in turn threads into the ring 51; of the cutter head. The screw60 is made with a different number of threads per inch from that of thescrew 62. In one constructiona 'tually used the s'crew'GO'had twenty threads per inch and thescrew 62 iiineteentlireads per inch. As the screw 60 is heldffrorn turnin'g'by the head 61',' one turn ofthescrew 62 will impart a movement to the blade 55. equal to the difference in the amount oflead ofltlie two screws. Thus, the two screws 60 ,62form a differential screw device enabling a very accurate adjustment of the cutter bladesto be made. Each of the bladesis seemed in an adjusted position by means of bolts 64 which thread into the foot portions 57 of the blades findlipass through the slots 54 in the cutter ground flat and the inside face of the blades also ground flat, the blades will seat accurately on the cutter head and will not tilt when being secured thereto 'or adjusted thereon.

As the blades are accurately ground inth'e With the sideface 520f thecutter head against a fiat surface on the cutter head is also utilized. The difference between the modification shown in Figures6 and 7 and that shown inFigures 3 tot inclusive is in the 5 means for adjusting the cutter blade in the cutter head. I.

In Figures 6 and 7, the cutter head is. indicatedat 7 0.. Its side face 71 is ground plane and. is iorinedwith'radial grooves 7 2. Radial slots 7 3 are :cut throughthe cutter head and communicate with the grooves 72. The blades 7 4 have their. cutting'jportions 75 formed in any usual or suitable manner and their foot .or supporting. portions76 are providedwith inside faces whichareiground fiat to rest on the side face 71 of the'cutter head and are provided with tongues adapted to engage in the grooves 720i the cutterhead. This construction is the sameas in the modification of sive, The supporting portions 76 have a stud 77 formed integral there-withand adapted to extendthroughthe slot.7 3 formed in the cutter head. Each of the blades 74 is adjusted radially onthe-cutter head 7 0 by means of a screw 7 Swhich threads through a nut 7 9 Y secured to the cutterhead and into the stud 77 ofthe blade. The blade is secured in any adjusted position by means of the washer 80 and the nut.81which threads onto the "stud 77 of the blade.- I g In the modification; illustrated in Figures 8 and 9, the principle of-afiat surface on the blade resting against aplaneside face on the head is again used. Here the cutter head is designated-at I It is again provided with a plurality of radial grooves 86-and.

with transverse slots 87'communicatingwith these Jgrooves. i-The cutter blades',-.of which .only one is shown, have cutting portions 88 and supporting portions 89. The supportingv 'portions'89pas inthe. caseof the. blades il- -lustrated in Figures-3 to 5. inclusive, have plane inside faces adapted torest on the plane side face 90: of thecutter head and have stongues adapted toengage in the grooves .86 of the cutter head to guide the blades 'in -their radial adjustments on: the cutter head; Each of'the blades is provided with anintegral stud 91- which is adapted to extend through a slot-'87: of the cutter head; Each blade can be-adjusted in the cutterhead 85 byfmeans of the-screws 92;and 93 which engage opposite sides of the stud 91'. V The screw v93 is heldiagainst rotation by means -of .a pin94 that engages in a slot 95 cutlongitudinally; in thev screw and, the screw threadsinto a nut 96 that is held between the side walls of arecess 970L113 into the cutter 160 head inalignment'with the radial groove 86.

.Each blade is held'in any adjusted. position by meansqof thewasher 9.81and thenut 9.9 that threads onto the stud 91 of the blade. Figures 10 and 11 show a further modifica- 1 .tion of theinvention Qmployingithe principle.

the invention shownin-Fig'uresB to 5. inclu-.

manner of Patent No. '1,236,83 i-above-.re-

tionand whether the blades have one or two i.

face 121 of-the cutter head-andisrformed of a fiat surface on the blade resting against a flat side face ofthe cutter head. ;;100[designates the cutterhead. Its, side facei 101 .is ground plane. and is formedwith a plua ralityofradialgrooves 102. Radialslots 103 are cuttransversely through-thecutter head in alignmentwith the. grooves 102. Only one ofthe cutting blades is shown. 104' designates the cutting portion of this blade and 105. thefoot. or supporting portion. The foot portion105has its insideface .106 ground. plane to reston the side face 101 of the. cutter head and is formed with a: tongue 107. which is adapted toiengage in a'radial groove 102 of the cutter-head to .%guide the blade in its end with a knurled head 111 whichis receivedi into aslot or 'recess 112 formed, in the cutter head; Each blade is heldin any. adjusted position'by means of a washer 113 and aunt 114 that threads on to the stud Figures 12 to 14 inclusive illustrate a fur.- ther modification of this invention in which it the principle of a flat surface on thebladeengagingja flat sideface of the cutter head is. utilized. designates the cutter head,- It is providedwith aplane side'face 121 and this. side face isfformed at equi-spaced intervals with radial grooves 122 while .radial slots 123 are cut through .the'cutter head bladesare formed with cutting portions 125 and with foot'or supporting portions :126.

fInthe' cutter shown, the cutting portions are allfarranged on acircle according to-.;the

ferred to and the blades are-alloutside cutting blades, eachblade having an outside cutting edge. It is to be understood throughout this specification that the invention is independent of the form of the cuttingportion and that each modification isfapplicable. whether the cutter-be constructed for employment'in an'i'ntermittent indexing operatlon or 1I1'L.COI1131I111011S lndexing operacutting edges and whether that one cutting edge be an inside or an outside cutting edge.

1 The supporting portion .126 ofeach blade has its inside face plane to-rnatchpthe side with a tongue 12'? which is, adapted to engage in a groove 122 of the cutter head. The blade has an integral .stud 128 adapted to pass through a slot.123..of the cutter head. :Badial adjustment of. the blade is effected by;

means of-screws 129'and 130. The screw 129 threads into the cutter head and engages the stud 128 on one side thereof. Each screw 130 threads into the cutter head for movement transversely thereof and is provided with a conical inner end 131. This inner end 131 is adapted to engage the beveled end of a pin 132 whichengages at its other end the stud 128 at a point diametrically opposite to the point of engagement of the screw 129 with the stud," It will be seen that by unthreading the screw 1'29 and by threading upthe screw 130, the pin 132 will be moved to adjust the cutter bladein one direction and by reversing these operations, the blade can be adjusted in the opposite direction. Each blade is secured in any adjusted position by means of the washer 134 and nut 135, the latter threading onto the stud 128.

. The idea of providing a plane surface on the blade supporting member to seat against a plane side face of the cutter head and thereby prevent tilting of the blade in its adjustment on the cutter head, is used in the modification of the invention illustrated in Figures 15 and 17 inclusive but here the supporting member is not integral with the blade but is constructed as a separate part to which the blade is secured. designatesthe cutter head. It is provided with a plane ground side face 141 and is formed with a plurality of radial T-slots 142.

Each cutting blade 143 is secured to a supporting member 144 by a screw 145. The inside faces 146v of the supporting members are ground plane to seat against the side face 141 of the cutter head. The supporting members are, also, recessed on their inside faces as indicated at 147 to receive the upper end of T'-blocks 148. A block 148 is secured to each supporting member 144 by a screw 149 an-d'a dowel pin 150. The T-blocks 148 are adjustable radially of the cutter head in the T-slots 142 by means of a differential screw device comprising the screw 151 which threads into the T-bl'ock 148 at one end and into another screw 152 atthe other end, the latter screw -152.threading into the cutter head.

Instead of providing a socket or slot in the periphery of each supporting member 144 into which to seat the cutting blade 143, it is deemed preferable to grind the periphery of the supporting member 144 as part of a coni- .0311 surface and grind a conical surface on the inside of the cutting blade. The conical surface on the blade is so ground, preferably, as to undercut the blade below its cutting portion', as clearly shown in Figure 17 and provide a shoulder 155 which is adapted to seat against the upper face of the supporting member 144 when the screw 145 is threaded home.

conical surfaces on all the supporting members simultaneously. Hence when the blades are assembled on the head they will all have exactly the same pressure angle.

Figure 18 illustrates another modification of the invention in which the supporting member is separate from the cutting blades and in which the inside face of the supporting member is ground plane to seat against a ground side face of the cutter head. designates the cutter head. It is provided with a plane side face 161 and formed with a plurality of radial T-slots 162. Each blade 163', as before, is preferably provided with a conical surface to-seat against a correspond ingly shaped conical surface 164 ground on the periphery of the supporting member165 and the shoulder 166 formed on the blade rests against the outer face of the supporting member. Each blade is secured to its supporting member by a screw 167. The supporting members 165 as in the'case of the supporting members 144 have their inside faces ground plane to seat againstthe side face 161 of the cutter head but the supporting members 165 are formed with integral T-shaped portions engaging in the T-slots 162 of the cutter head. .Each supporting member 165 is adjusted radially on the cutter head to adjust thecorresponding cutter blade radially of the cutter head by a screw which threads at one end into the T-shaped portion of the supporting member and at its other end into another screw 169 that threads into I the cutter head. The two screws form a differential screw device permitting of a fine adjustment. A lock-nut 17 0 may be provided to thread onto the screw-168 to secure it in any adjusted position, while the bolt 172" and nut 173v assists in-securin-g the blade in. its adjusted position. A

Figures 19 to 21 inclusive illustrate a further modification of this invention employing supporting members separatefrom the cutting blades. designates the cutter head. It is formed with a plane side face 181 and with a plurality of radial grooves 182. 183 designates the cutting blade and 184 the supporting members therefor. Here the cutting blades are secured on the inside periphery of the supporting members instead of on the outside periphery thereof as in previously described modifications. This serves to illustrate further the scope of this invention. The inside-peripheral surface 186' of each supporting member is ground conically and the inside face of'each blade 183 correspondingly ground and the blades formed with shoulders adapted to seat on the outside faces of the supporting memhers. Each blade is secured to its supporting member by a screw 187. The supporting members 184 have their inside faces 188 ground plane to seat against the side face 181 of the cutter head and are formed with i grooves189. Blocks 190 and 191 which. are secured in the groove -182 of the cutter head by dowel pins 192 and 193- engage-' in the groove 189 of each supporting memberb184 andserve to'guide the supporting member 184 in its radial adjustment on the cutter head.

No special means has been illustrated for adjusting the supporting members 184 on the cutter headand it will be understood that any of the means heretofore described or' any other suitable means may be employed for this purpose or that the cutter truing fixture may be arranged so as to effect this adjustment. Each supporting member 184 is secured in any adjusted position by means of a screw 195 that threads into the cutter head 180 and a washer 196 which engages the.

supporting member. 184. Preferably, the. supporting member 184 is recessed, as indicated at 197 to receive the head of the screw 195 and the washer 196. Y

Figures 22 to 24 inclusive illustrate further embodiment of the invention. Here,

' by means of a dowel pin 204. 205 designates the cutting blade and 206 the supporting member to which the blade is secured by means of a screw 207. The supporting member 206 is, preferably, provided with a conical peripheral surface 208, as in the preceding embodiment, and the cutting blade 205 is formed with a correspondingly shaped inside face adapted to seat against the peripheral face 208 and with a shoulder 209 adapted to seat on the outer face of the supporting member 206 whenthe blade is secured to the supporting member.

The supporting member has its inside face 210 ground plane to match the side face 201 of the cutter head against which it seatsand the supporting member 206 is formed with a groove 211 in which the block 203 is adaptber 206 in its'radial adjustment on the cutter head. This radial adjustment may be effected in any suitable manner; The supporting member 206 is secured in any ad justed position by means of screws 212 which pass through the supporting member, one on either side of the groove 211 and thread into the cutter head 200 on either side of the tongue or block 203. The supporting member 206 is preferably recessed as shown at 215 and 216 in Figure 23 to receive the heads of the screws 212 and the washers 217.

Other modifications of the invention are possible as will be clear to those skilled in the art to which the invention pertains. In.

general, it may be said that the invention is capable of various further modifications and uses and that this application is intended to cover-any variations, uses, or adaptations of the invention following, in general, theiprinciplesof the invention and including such departures from the present disclosure as come within known or customary practice in the art to which itpertains and as may be ,app'liedto the essentialfeatures hereinbefore set forth and as fall withinthe scope ofthe invention orthe limits of the appended claims. 1 Having thus described my inventionnvhat Iclaim is! A ge'arucutter. comprising a rotatable headhaving a radial grooveformed therein "and a radial:slot.communicatingwith said groove and. having a plane side face, a blade having a cutting portion projecting beyond the adjacent side face of the head in thedirection of the axis of the head andv a supporting portion formed with a plane face adapted ting po rtion having a side-cuttingedge,

"means foradjusting the'blade radially on the head and means adapted to .besecured to said stud for holding the blades in any. adjusted position." Y Y 2. A gear cutter comprising a rotatable head having a radial groove formedtherein and a radial slot communicating with said to seat on the plane face of the head and with V a tongueengaging in said groove and having a stud which passes through said slot connected to said supporting portion, said cut-' 00.

groove and having a plane side face, a blade having a cutting portion projecting beyond the adjacent side face ofthe head in the direction of the axis of the head and a sup- 7 porting portion formed with a plane inside face adapted to seat on the plane faceof the head and with a tongue engaging in said groove and havinga .stud connected to said supporting portion which passes throv gh said slot, said cutting portion having. a side-cub ting edge, means engaging said stud for 3dr] justing the blade radially on the head, and

means secured to the stud "for holding the j blade in any adjusted position. L ed to engage to guide the supporting mem- 3. A :gear.cuttergcomprising a rotatable head having a radial groove formed therein and. a, radial slot communicating withsaid I V groove'and having aplane side face, a blade havinga cutting portionprojecting beyond the side face of the head in the direction of 3 a tongue'engaging in said groove and havinga stud connected to said supporting portion which passesthrough said slot, sald cuttlng portion having'a side-cutting edge, apinengaging-said stud-having abeveled outerend,

m re-wforaadjusting the blade radially on the head, said screw-beingthreaded intoth'e head transversely thereofand havinga ta.-

pered noseengaging the bevelof said pin,

and means for securing the blade in any ad justed position.

4. A gear cutter comprising a rotatable head having a radial groove formed therein and a radial slot communicating with said groove and having a plane side face, a blade having a cutting portion projecting beyond the adjacent side face of the head in the direction of the axis of the head and a supporting portion formed with a plane inside face adapted to seat on the plane face of the head and with a tongue engaging in said groove and having a stud connected to said supporting portion which passes through said slot, said cutting portion having a side-cutting edge, and a screw threaded into said head and engaging said stud for adjusting the blade radially on the head. a

5. A gear cutter comprising a rotatable head having a plane side face and formed with a plurality of radial slots, a plurality of blades, each of which has a seating portion, the underside of which is plane and is adapted to rest against the plane side face of the head, a cutting portion extending from said seating portion beyond the adjacent side face of the head in the general direction of the axis of the head and having a side cutting edge which is inclined to the axis of'the head, and a shank-portion which engages in and passes through one of the slots of the head, means engaging the shank-portion of each blade and movable in the head for adjusting the blade radially in the head, and means for securing each blade in position after adjust ment.

6. A gear cutter comprising a rotatable head having a planeside face and formed with a pluralityof radial slots, a plurality of blades, each of which has a seating-portion, the underside of which is plane and-rests against the plane side face of the head, a cutting portion extending from said seatingportion beyond the adjacent side face of the hgad and having a side-cutting edge inclined to the axis of the head, and a cylindrical shank-portion which engages in and passes through one of the slots of the head, and means engaging the shank portion of each blade and movable in the head for adjusting the blades radially in the head, and means for securing each blade in position after adjustment.

7. A gear cutter comprising a rotatable head having a plurality of radial slots formed therein, a plurality of removable cutter blades, each blade having a shank-portion which passes through one of the slots of the head, and a cutting portion, which, when the blade is in position on the head, extends beyond the adjacent side face of the head in the d rection of the axis of the head and prov ded wlth a side cutting edge which i i clined to the axis of the head, means for

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