Патент USA US2404148код для вставки
July 16, 1946. ~ R. A. THOMPSON 2,404,148, GRINDING WHEEL DRESSER Filed Aug. 5, 1944 3 Sheets-Sheet 1 July 16, 1946. R. A. THOMPSON - 2,404,148 ' GRINDING WHEEL DRESSER Y Filed Aug. 5, 1944 ' _ 3 Sheets-Sheet 2 BY M ,qrra/f/YEKs. July 16. 1946» R. A. THOMPSON"). 2,404,148 GRINDING WHEEL DRESSER Filed Aug. 5, 1944 3 Sheets-Sheet 3 4a /8 97.98 4" /0/ ‘9; .99 ~94 .96 ?TroR/VEYS. Patented July 16, i946 2,404,148. UNITED STATES FATE Nr OFFICE‘ ' . 2,404,148 _v 4 _ GRlNDING WHEEL ,in'inssna I Richard ‘A. Thompson], etroi‘t; ‘ Colonial‘ Broa‘ch Com pany,‘~ ' corporation of Delaware assignorto ‘ i Detroit,'~ Mich.) 5a V. Application August 5', 1944,.saaigqgisitif . 4‘Claims.”r(Cl. 125-11)‘ I _Thefpresent ‘invention relates to a grinding‘ p ' 2 > ' j wheel dre'sse'r'adapted to dress arcuate surfaces or Referring to the drawings, and particularly to Figures‘l to4 thereof,ithe dresser comprises a base ery of a grinding wheel. It'is‘p'articularly adapted plate I adapted to rest on the table of a grind: inghmachine. The base plate is provided with-a straight line surfaces at any angle on the periphl for use in‘dressing the wheels employed in grind‘ splitkey formed by two pairs .of downward pro- _ ing splines or spline broaches, but may be em_-: ployed for other purposes. ; jecti‘ons, each pair including projections. _2 and . 3 which are formed as depending ?anges on a The primary object of ‘the invention is ‘to ‘pro pair'of plates .3 and 4’ respectively,‘ slidable to videa rugged, accurate,‘ and simple dressing ?x wardiand from‘ each other in the'bottom of plate ture adapted‘ to dress awide variety: of wheel 10, I ; The position of plates 3 and 4 is controlled forms-U... v Anotherobject of the invention -, ,‘ is tovprovivde a by. means of a pair of adjusting screws '5 and 6 dresser of the type mentioned _in_ which allneces: which. are‘ mounted ‘in countersunk openings in ‘ the, side edges of the plate I and are ‘threaded into ‘the members 3 and 4 respectively. A pair of by means of accurate measuring blocks such as '_ 15 cap screws ‘I, indicated in dotted‘lines at the left‘-v the familiar Johannsen blocks. ‘ H p , ‘hand side‘ of Figure 2, are .?tte'din suitable slots Another object of the invention is to, provide a in the members 3'and lLto retain them against machine of the type mentioned in which a mini the bottomsurface of theplate, I, with freedom mum number of relatively moving parts are em for sliding’imovement relative to the plate'under sary adjustments maybe flxedwandndeterminedv ployed and in which,‘ forany given form‘to be" 20 the’ in?uence of the screws 5 and'6.t The split dressed, all relatively movable partsv are ?xed key formedv by the projections 2 and 3 ?ts within‘ against relative motion except. two parts which the keywayon the table‘ of a grinding machine. move relatively to effect the ‘desired’ motion of By adjusting the members 3 and 4 an vaccurate the dressing» tool. > ‘n I 1 _, Another object of the invention is to provide 25 ?t of ‘the key in the keyway may be maintained. In addition, if the k'eyway becomes‘ Worn it may a dresser of the type mentioned'in which means be reground 'to a slightly greater. width by the I employed’to adjust the location of the toolfor grinding‘ wheel of the machine, and the split key dressing straight surfaces is employedto effect adjusted to .?tthe increased width. This assures the necessary movement of thetool in ‘dressing maintenance of the accuratelocation of the fix curved forms and vice versa, thus increasing the ture as a Whole with respectitothe plane of the versatility of the machine without corresponding-Y ly increasing its complexity. . V v grinding 'Th‘e'base wheel’. plate “II ‘ is provided with a pair‘ .v of Other objects and advantages of the invention will become apparent from the following speci?: upstanding apertured ears .8‘l'and 9 ?tted'respec tively with bushings I0 and II in which is jour cation, the accompanying drawings, and’ theap pended claims. ‘In the drawings; , naled a shaft I2. The shaft is ?xed against rota- ‘ 7 / " tion by. means of a setscrew I3, indicated in , ‘_ dotted lines in Figure 2. Figure 1 is a vertical section through the fixture as ‘viewed from the left side. 7 a v _ Figure 2 is a rear elevation of the invention with portions broken away to show the interior. , '_ ~ , _ Pivotally mounted uponthe. shaft I2 is a .box like‘ frame structure‘indicated‘generally at I4. 40 This frame‘ comprises a pair of integral front and backv walls I5 and I6 joined together at 'their' Figure 3 is a plan view of the invention. Figure 4 is a front elevation. lower' portions by means of a connecting portion Figure 5 is a fragmentary sectional view taken of ?anged bushings I9 and Marc ?tted within on the line 5—5 of Figure 1. 45 Figure 6 is a fragmentary section taken on the‘ line 6-6 of Figure 1, showing the means for look ing the dressing tool slide relative to the rotaryv support therefor. I‘! in which islformed a transverse bore I8. . A pair: v , thebore I8 and‘are ‘rotatably .J'Qurnaled on the ' shaft I2. I Apaifof spacing’, discs 2| and‘22 form an axial; thrustjbeari'n’g forgthe assembly,. and consequentlyaccurately locate the axial position _ . . " Figure '7 is a diagrammatic illustration of one 50 of'the frame III on the shaft I2. Above the connecting vportion ll of the frame form of spline grinding wheel which ymay bev 7‘ ' I4'the frame is‘vprovided’ with a pair of side wall dressed by the invention. . . members >2_3"an‘d1-2'II indicated in dotted lines in Figure8 ‘is a diagrammatic view'of a second Figuregiljand 3‘ and, also shown in sectioninrrFi'g form of spline grinding wheel which may be dressed by the. present invention, ' 55 ure..5'.§ The side wall members 23_and ninete cllféd' to the 'front‘a?dbjack 0f memberslby means 2,4o4,'148 , ' 511» 4 Q1 the auxiliary slide 55.’ The wedge member 60 is of countersunk cap screws 25,-shown best in Fig ?xed to the end of a rod 6 I , which extends through ure 2, to form a rigid structure. the tubular spindle 4| and is provided with a pro‘ jecting threaded extremity carrying a thumb nut '52. A s a result of this arrangement tightening ' of the wall members The upper ends |5, H5, 23, and 24 are secured by similar cap ‘screws 26 to a top plate 721. A generally rectangular block-shaped ‘slide 28 ' of the nut 62 will lock the auxiliary slide 55 ?tted between the walls l5, I6, 23, and 24, and is ' againstt radialgvmovement, with respect, to the axis slidable vertically therein, such slidingv movement oiiiheiubulal: spindle “1-. - j - ; r ., . being eife‘ctedwb-y means; of a handle 2,9_ fixedotob The auxiliary slide 55 carries the dressing tool the end Qfa double screw 30. The screw 30 has which’ may be in the form of a pointed diamond. _. an upper portion’ 3| provided with a left-hand’v 19;. " The diamond’ may be mounted in any suitable thread and a lower portion 32 witha right-hand . mannerg'lbut two alternative mountings are illus threaded-through > r ‘ thread. The upper portion is .Ttrjatediu the, drawings 7 One of the illustrated’ a threaded bushing 33 ‘?xed tothe top plate; 21, diamon jholdefsfisin the form of a generally While the lower portion 32 isjthiiéwidédwithinl a v I ' threaded bushing 34'?xed to the slide 28. ’ Haired, 63:;having a stem 64 accurately . ’ enter Asfa ?tted within. a suitable bore within the auxiliary consequence of this arrangement vrotation ‘ofthe slidev 55 and extending parallel to the axis of the handle moves the slide vertically Within the frame ' l' The stem 64 is provided with ' I M in either direction. j ' V I . n - - »' »_ tubular-spindle 4|. .a notch 65 adapted to receive a sets'crew 66 for‘ ‘ V The slide 28 is provided with a circular'o-pening 35. extending parallel to ‘the axis of the shaft 1.2 ‘ lockinglthe holder inposition. The holderis also PIiOViQQd'iWith 2» flange 61 having 2», depending-P0P. tionf?iifwhich,‘ as best‘ shown in Figure ‘l, ?ts‘ 20 and adapted to receivea tubej36u The tube 36. is keyed'torthe slide 28, by means ‘of akey, 31 which Lwit'hinja keyway 59in the auxiliary slide and: thus ' isflocked in position by means ‘of a setscrew 38." ?xeethe rotati'ye‘position of the ‘holder relative The rearwall I5 of the frame is provided with a to theslida Thediamond point"), in accord and the front wall I?is provided ance with conventional practice, is ?xed to a » 'vertical'slot as, with a similar slot 49 through which slots the tube ' cylindrical element‘ it which" in turn 'is ?tted 3&6 projects freely. The slots are of su?icient ' within a transverse opening in‘ the holder 63 length to'permit the maximum‘verticalmovement of the slide 28 relative to the frame l4 without’ interference. . The tubular. stem 4|, of a rotary support 4; is and lockedin; position by means of/avlong set- ' screw 12 shown'nin dotted-lines in Figure 1'. ‘ The " 30 opening in which the element 1| is mounted ex: tends» ‘parallel’ to the dove-tailed tongue and groove connectionbetween the auxiliary slide 55 journaled within the tube 35‘ for rotary move-' ‘ , ment on an axis parallel to the shaft l2 under and-therotary support 4-2.~ If - desired,'a second the influence of a crank 43 keyed to a reduced 7 extension 44 or. the tube stem 4|. is ?xed to ‘the tube 35 by'means of alkey 46, and‘ ‘diamond 13' may be‘; similarly mounted further out on the holder 631 for use» in connection with grinding wheels» oil larger diameter. It will be a similar disc 41 is hired to the tubular stem 4| ' understood’v that only» one diamond will be eln-j by means of keyways 48 and a lock nut 49 threaded on the reduced portion 44 of the stem‘ _. ployed at onetime. 41; The disc 41 is provided,‘ withan accurately formed, hole 50,, and the disc 45'is provided with four. similar holes, 5| spaced 90° apart around ' ~ slide 55‘ and.screwf55ji'arsecond diamond holder distance from the axis of the tubular spindle4| - than does the1holder36'3. This'lholder, as ‘shown in other and parallel to the, path of movement of the‘ slide 28..‘ The holes 50 and 5| are adapted Figure 1, comprises a- bracket 14' ?xed to the aux- ' ' iliary slide 55 by means of a key'l5 and cap screws to‘ have a, push ?t with a bushing 52 ?xed on a it is. i pin 53, having. a handle 54. As a result, . 36 in any oneof four“ ' ' ' is provided which-positions'a- diamond ata greater 45 being vertically positioned‘ relative to each port '42'relative to the tube ' J'ustment of" the diamondv point by 7 the auxiliary the disc, ‘the upper and lower holes 5| in the disc possibleto ?x; the rotative position of the sup-v " _ In Vorder'to increase; the effective range'oi ad‘ 16; "It carries a diamond holding element '|'| pro vided'with a diamond point 18. Theelement ‘His locked iniposition by means of a set screw 19p It ' 50 willibe observed that by rotating the spindle 4| positions spaced '90?’ apart. When thepin 53’is' removed it will be obvious that the support is ‘ through an angle of 180° that'the diamond ‘Hi-may freely rotatable relative to the tube 36. n . the» diamonds be swung into the angular position occupied by 10* andi'l3, but will‘ be spaced at a greater distance than the latter from theraxis of ' An' auxiliary slide 55 is mounted upon the re tary ‘support 42 by means of the tongue. and groove connection shown best in dotted. lines} in the tubular spindle 4|. Figure 3, with the result that the auxiliary slide .may move radially with'respect V to spindle 4|.. This the axisyof the movement is accomplished by; ' meanss‘of a doublescrew 56 having a portion 51 . 7 The diamond holder 63 is sov positioned on the 6o at its upper end'provided with a left-hand thread and a‘portion 58 at the lower ‘end provided with a. right-hand thread. The portion 51 is threaded in a'blockn 59 ?xed to the upper end of the auxil slide 55 and the diamonds 1b and'13 areso posi tioned relative to the holder, that. when the sur face 8|! of the'block 59-contact's the surface 8|_ of the rotary‘ support 42 the point of the diamond will be exactly on the axis of-vspindle 4|. As a result, the radius of movement of the ‘diamond point‘ e?ected by'swinging'thecranlglhandle 43 maybe exactly determined by inserting measuring blocks iary, slidej55 while the lower end 58‘ is threaded‘ c5 between‘the surfaces‘Bil "and SI and thereafterg?xe ' I into‘ the rotary support 42. ' As a?result ofi this ' inglthe‘ auxiliary slide relative'to the rotary Sup arrangement rotation .of- the. screw. 56v shifts, the.. port'42 by means of the wedge '50; The distance radial position of. the?auxiliary slide 55 relative between the diamond point 18“ and 'theaxes' Qfthe' . to the axisofthe tubular spindle 4|. ‘ ‘ 4|f preferably such, that} when. ' 'Thejadjusted position or the auxiliary slide55. 70 the surfaces 8!) and -8| arein'contact, the dis a , wedge-shaped” block 7 may; be ,?xed by, means of tance between the point 18 ‘and the .axisef; the tuular spindle 60, shown best. in Figures spondsngenerally, to , the , shape of ‘the dove-tailed,‘ tOhEU-QQH the. to ‘nary. support 42, and ?tswithinl'l the central portion of the dove-tailed groove in. ‘ V ' ' Spindle 4| equals themwsimumdist'ance tolwhich. ' diamond point. inmate; shifted seminar; . 75a‘. the axis by means of the‘ screW'56. Thus; the two $404,148 diamond mountings double‘ the effective: range‘ of I m'ovementof the'auxillary slidei55-5 - ‘7 I'Ijhe ‘operation of the'imechanism‘ may ;bestz.be: ' I understood by ‘reference’, todiagrammatic; Figures ' As best shown'in ‘the broken-away-portion :of 7 and‘8. ' In Figure 17 is illustrated ariragnientiot Figural-the‘ side wall 23 of the frame ‘I4 is pro-J vided with an opening 82 through which'may be a‘ grindingiwheel :I 02 adapted ato‘v f'grindthe space between apair' of teeth, indicated in- dotted lines; , inserted measuring blocks of ‘known dimensions at’ " I03 and 104;:- of! a ‘straight-‘sided splineifon- ‘ in order to determine the vertical position of the. splined'fbroach having a @1'001': iradius represented; slide 28 relative to the “frame "I4. - A pin: 83 is b'y-ithezkiirc’le ‘1051M In: such a-xcasei the ‘portion A ?xed in the threaded bushing 34 of the s1ide>.28,l of' the face 'ofithe. grinding‘ .wheel must be dressed f and a pin 84 is ?xed to the cover plate 21.1“ These‘ 101 teen arc equal“ to the radius of the circle I05. pins are so constructedfthat fora known ‘distance Forsuch: dressing operations the frame I4 is ?xed between them, which may be determined by. the‘ in *a' verticalpos'ition'in which the rolls 81 and 88 measuring blocks‘,'the distance between’the axes‘ are equal distances'f‘rom the locating blocks‘ 92‘ of ’ the shaft I 2 and the tubular spindle‘ M is and 93, respectively. This is accomplished; by known. Consequently the opening 82 and'the pinsv the use of anaccurate measuring vblock equal to. 83 and‘ 84 provide a' means for accurately-deter the known'distance between the plane of the_;up-1 per surfaces ofthe blocks 93‘ andlthe axis of shaft I 2 less’ the radius‘ of the: rolls , 81 and“. The main slide 28- is then elevated‘ or lowered (by means of the handle 29 until the axis of the spin-i dle'4I is on- the'center I05 of the cir'cle- I05. mining the distance‘between‘ those axes. ‘ As best shown in Figure 2 the frame I4 is pro» vided with'a pair of ‘triangular boxlikeiproje'cte ing ears 85 and 85, to each of which is secured a cylindrical roll 81 and 89, respectively. The/rolls‘ are secured by'cap screws 89 inpos'itionagainst a pair of accurately located‘surfaces- 90-and ‘9|, formedonthe ears 85-, which ‘surfaces extend at“ right angles to each other. > The rolls-81' and' 88% are made'with great accuracy, and by the means J'ust'described are exactly located so that the _ common plane of their axes contains the ‘axis of The base plate I is provided at each sideibee neath ‘the rolls3 8‘! and 88 with a pair of blocks 92 and 93 having accuratelyfor'med topsuriace's positioned in a commonlplane at an accurately known distance from the axis of "the shaft I=2'.I3 As best shown in Figure'l, the top‘surfaces ofzthe blocks 92 and 93 are provided with dust collecting; grooves in‘ order toi insure *that 9 measurements: made from- the‘surfaces willinot be impaired'by any grinding dust which might fall on them. The This is ‘accomplished by inserting appropriate measuring blocks between the pins ‘83 and 84 shown in Figure 2 and adjusting theslide untilv the proper distance between those pins'i-is achieved. This distance maybe calculated from. theuknown distance between'theend of- pin I34vv and the axis of the shaft I2, the known-distance ' between the‘ end of pin 83’and the? axis of spindle 4|, and ‘the known distance between thev axis: of» shaft I2 and the axis ‘I05? of the workpieceai auxiliary slide is then ‘adjusted until the ‘distance between the surfaces 80 andv 8|! isv equal to the“ radius'of the circle I05i Then with the slides“ ‘- and 55 ‘clamped, the rotary support“ is oscillated by' means'o'f’ crank 43 to dress the wheel. ‘ It will be understood inthis connection that the axis of the‘ shaft ‘I2 and the tubular spindle 41 are at r , The ' all timesparallel to they plane of the‘ grinding rolls 81 and 88 in combination-with the locating 40 wheel, and that in the dressing of a surface cor-. blocks 92 and 93 provide a means ‘by ‘which the responding with surface A in Figure 7 that they angular position of adjustment of‘the frame I4 are preferably located in the central plane of the about the axis of- the shaft‘ I2 may be accurately Wheel. Pin 53 will be removed during this dress determined. For any given angle ‘the distance ing operation in order that spindle 4I may rotate between one of the rolls and ‘its corresponding do" freely. ' ' locating block maybe readily determined or cal As angeneral rulegrinding machines for spline‘ culated, and measuring blocks of the proper‘di grinding maintain the work on a ?xed axis and mensions inserted between‘ the ‘rolls and the 10‘ consequently-it is not necessary to change the: cating ‘block to ‘accurately locate the angular po-I sition. _ " v " ff" I adjustment‘ of the slide 28 to dress arcs of differ I so" ent radii. It is contemplated that the shop prints In‘ order to ?x' vtheYframeIIl in‘an‘yladjusted for the ‘particular workpiecetobe'made will bear angular position a-cla'mping' meansisprovided as a notation'of the measuring block settings for best'shown' in- Figure 5.v As there shown‘, the lower the distance between the pins 83 and 84, distance 3 portion ll of frame I4 is “providedlwith ai'trans between the surfaces 80 and 8I,- and the distance“ verse‘bore 94-in'which are slidably ?tted a pair 56 between the rolls-81 or 88 and‘t-he blocks'92'or 93;: of plugs 95 and 90; The 5bore 94 intersects the Consequently, no calculations need to be made bore I8, and ‘the plugs 95 and-95 are provided with by the ‘operator of the machine. I > » cylindrical surface portions 91- and.‘ 98, respec tively, adapted to‘?t'against'the'shaft I2. ‘A socket head screw 99 extends through and is‘ freely rotatable with‘respec't‘ to the plug 96, and is threaded through the plug 95 with the result so that upon tightening of the screw the plugs will be drawn‘ together'and clamped against the fixed shaft I2, thus preventing rotation ofthe frame relative to the shaft. 'In order to prevent free movement of the frame about the shaft I2 when the screw 99 ‘is loosened, the screw is provided with a nut I00 which is ?xed thereto in any'de sired'manner, and a‘ spring -IOI- surrounds the screw and is located between the nut- and the clockwise direction from the position illustrated» in the drawings and ?xed in that position by meansv of pin 53; This results in an inclination of‘ the. dovetailed ways of slide 55 in a direction along ‘the, line c,—‘c.v ofFigure 7, with thendiamond» plug 95. Consequently, when the screw is loosened the spring maintains sufficient clamping action tending to draw the plugs together to prevent the ‘frame from moving by gravity: ~ ' - - ~ In order "to dress the’ straight sides‘ B of the wheel I92 the main frame I4 is swung about the axis of the shaft I2 until itextendsiat an angle from the ‘vertical equal'to the angle a between the pro?le B and the central plane of‘ the wheel. The center-line of the‘ frame I4 then occupies the line b’b' ‘shown inlFigure 7, which is parallelto the line b+b lying in the surface Btobe dressed; The spindle 4| is then .rotated 90° in a counter in point directed to‘ the leftalong that line as-viewed in Figure‘ 7. The small slide isithereupon adjust-i ed by screw 56 untilithe diamond point lies; in the line ‘be-b; The small slidei-is thenclamped anemic " proper angular position ionitheooppositei side of - bylim'eansl oft 5e trims nut ?liandithe; wheel is : the‘ frame of therwhe'el; - This position may be de ’ dressed -iby1_rotating:.the: handle '29 "to‘ shift- ‘the ‘ termined by the same’ measuring blocks required main slideib'achv and forth along the line b'bx; to ~. locate the angular; position employed at the V "be I It i will understood that the setting ofthe i right side of the wheel as viewed. in Figure 8. V mainframe on theiangle a maybe determined with: great accuracy‘ by means‘ of ‘measuring blocks-‘inserted between thelro‘ll 88 and thelbloick a It'will be observed that there’ is provided; in accordance! §_With' the, present. invention, arela tively simple dressing ,device of rugged construe; "93. r The thickness ofrth'e measuring blocks may 7 tion in which all adjustments may V ' be "readily calculated or. determinedifrom ordi 10' with ‘great (accuracy * by’ means nary trigonometric tables and the knowrrdimen 'sions of. the dresser. Likewise the, setting of the auxiliary slide 55 may be accurately calculated-to be determined of measuring 7 ' blocks, “In addition}: it will‘rbe noted that the de vice is: flexible incapacity to; dress various ar rangements? of straight or arcuate pro?les_-, but _ determine‘ thelaccurate‘ thicknesses of the meas that such: ?exibility is ‘not achieved by additional uring blocks to’ insert between the'surfaces LB!) and" f complication of the mechanism, vThus, the rotary 8 l l in orderto" insure thatv the diamond point will. 15 movement. of the diamond provided by the pivotal ‘mounting of spindle M is employed to‘ perform the‘ be upon the line 6-4) ‘of Figure‘ '7- ‘duri-ng the dressing operation. It will be understood that dressing operation in the case of arcuate pro?les the‘ angular position‘ of the» g frame ,I 4' will be: ?xed ' by'tightening the clamping blocks 95 an‘d‘tt of Figure 5 prior to the dressing’ operation. 'It will‘. be appreciated that" in order to andqis‘ employed to adjustthe diamond into a pos'ition at right angles to the surface to be dressed when dressing straight pro?les. The sliding movement of the small slide 55- is-gutilized dress’ thefstraight surface on the opposite side oft-he wheel it will'onlybe necessary to rotate the spin dle 41 through an angle of 180° from the position it occupies in dressing the: surface 3, and to ' to'?ix-the radius-in of the planeof the wheel at the same, butv oppoe, site, angle"; 7' .r, " ; " i tact with the; wheel 'in'preparation for the dress’ The main slide'is em_-_ f 'ing. of straightipro?les, ployed to position thespindle 4| on the center ,of an arcuate-ppro?lewand- is employed to, effect the rectilinear dressing movement in dressing» a 25 ; swing themain-frame l4 over to‘ the opposite side ‘ dressing arcuate vprofiles and ' is/employed tov feed the diamond point into com I l > Theldresserisaal'so adapted'ito dress arcuate straightpro?le. Finally,- the swinging movement sidg'areassuch as thearea.E Con thejwheel I09" of. the frame 14 is employed to“ locate the axis ofthe spindle M on- the centerwof an; arcuate ‘ indicated'diagrammatically in Figure 8; Any de-' sired arrangement of arcuate side surfaces: may profile to bedressed, and is employed to adjust be 'dres‘sed,-but,iin, the particular example illus the plane of movem nt- of the diamond to cor V trated, C‘ is an arcuate; grinding pro?le which is 3.5; respondv to-the angular position of a straight pro ?le; towbe. dressed, Thus,‘ each’ of the relative quired to dress the sides ofinvolute splined-teeth ' movements oradjustmentsi- provided in the ma- ' In this connection it ' indicated in ‘dotted ‘lines.’ chine is employed in dressing; both types of pro- j may be noted that on small splines it ispossible ?les‘ and no additional adjusting means are nec intended to approximate the involute- form re involute curve with great ac essary for either type; curacy by a true circulararc or, in some cases, 40 7 to approximaterthe What i'sclaimed is: 7 7' _ V g a ‘combination of two tangent arcs of different radii. The center or centers of‘ such arcs and l.- A» grinding wheel dresser comprising‘a base, ‘ V ofzv the center ,ofrsuch are, indicated at‘ H0 in said- second slide with its point projecting in a direction. parallel to; the path of ‘ movement of the a frame pivotally connected to the base,‘ a slide theirradii may be determined by- mathematical movable‘- on the frame in'a pathv at rightangles calculation or by laying out the true involute on 45 to the axis» of» said pivotaluoonnection, a. support a greatly enlarged scale, such as ?fty to ‘one hun rotatablypmounted on’ said slide on an axisrpar dred or one hundred to- one, and determining the allel/to; said ?rst mentioned axisra second slide 7 center location and radius of the proper circular movable onisaid; support in a path at rightangles arc-orgarcs graphically; Invv either event, inac tot-heaxis- of movement of the support relative corda-nc'e'with the present invention, the location 50 to the ?rst slide, and a dressing tool carried by Figure 8; is determined with respect to the axis of the shaft l2 and,in addition, a, determination secondslide relative torthe support», said basehav is made'iof the angle at between the central plane of the wheel and the line b’b' of Figure 8,"which extends through the center I ID of the arc and the ing- a flat reference'surface extending parallel to" 55 theaxisi of said frame, and means on sa1d"fr_am'e" " axis of the shaft i2. Once this information is determined graphi cally or by calculation, the‘ frame I4 is pivoted withlrespect tothe vertical-by the angle a’r which angular" position, as previously mentioned, is de-r termined by measuring blocks inserted between the roll 88- and the‘ block 93.’ _ 'l‘hereup'o'rr the main‘ slide 28' is adjusted along the line b'b‘ until the . center of the spindle 41 coincides with the. center H0 of the ar'c'of the radius tolbe‘i'dri'essedl ‘The’ small. slide 55 is then adjusted- by screw Eli-"until the distance between the surfaces: SOIL-8|‘ equals the radius of the arc, C,lwhich is-to' bedressed. This position of, the‘ small slide 55' is ?xed by means of the thumb nut 62' and the wheel is then dressed'by swinging the-diamond- point; about the axis‘ of‘ the spindle M by manipulation of the han die-43.. The OPPOSltGSidG'Of’thGl wheel may be dressed in the'same-‘m'amier. without any'adjust mentieiiceptia shift‘ "of the’ mainframe’ l4‘v to the; offset» from’ its-axis- de?ning a curved surface adapted to remain tangent to planes‘ parallel to said referencesurface, in all- pivotal positions of , said frame; said reference surface and said means 60 being in juxtaposition to receive between them measuring blocks for‘ determining the angle of adjustmentof the» frame relative to the base, 2; A1 grinding wheel- dresser comprising a base, a frame pivotally connectedrto the base, a slide movable on the frame in a path at right angles to- the axis-of said pivotal connection, a support rotatably mounted on said slide on an axis- par alleli to: said ?rst’ mentioned axis,v a‘ second slide movable on said: supportirr a'path at right angles to‘the axis of movement-of thersupport relativeto the ?rst slide, and a dressing toolcarried by said second slide with its point projecting in a direc tion' parallel to- the path- of movement of the second slide relative tothe support, said support and second slide: havingzsurface:portions which, 2,404,148 .10 move toward and from each other and remain in axis of the support, and said dressing tool being alignment during movements of the second'slide relative 'to the support and between which meas so positioned on said second slide that its Wheel engaging point is located on the axis of the sup port when said surface portions contact each other. 4. A grinding wheel dresser comprisinga base, uring blocks may be inserted to determine the adjustment of the dressing tool relative to the axis of the support. 3. A grinding wheel dresser comprising a base, a frame pivotally connected to the base, a slide movable on the frame in a path at right angles to the axis of said pivotal connection, a support ro tatably mounted on said slide on an axis parallel ' to said ?rst mentioned axis, a second slide mov able on said support in a path at right angles to H) a frame pivotally connected to the base, a slide movable on the frame in a path at right angles to the axis of said pivotal connection, a support rotatably mounted on said slide on an axis par allel to said ?rst mentioned axis, a second slide movable on said support in a path at right angles to the axis of movement of the support relative to the ?rst slide, a dressing tool carried by said, second slide with its point projecting in a dimetion parallel to the path of movement of the second slide relative to the support, and means for ?xing the support relative to the ?rst slide in either of two rotative positions 180° apart, in the axis of movement of the support relative to the ?rst slide, and a dressing tool carried by said second slide with its point projecting in a direc tion parallel to the path of movement of the sec ond slide relative to the support, said support and second slide having surface portions which move toward and from each other and remain in 20 both of which positions the point of the dressing alignment during movements of the second slide tool projects in a plane at right angles to the relative to the support and between which meas direction of movement of the ?rst slide relative uring blocks may be inserted to determine the to the frame. - adjustment of the dressing tool relative to the RICHARD A. THOMPSON.