' 2,411,851, M. CASERTA ‘ Dec. 3, 1946. APPARATUS FOR AND METHOD OF SMOOTHING PUMP BORES Filed April 17, 1944' 3 Sheets-Sheet l 7- v 42b 3_ 02/9 __‘7. _| v|r. 27/ a R7' ,2 "-www27R‘, ob”27%65%w ai1]l: 0O 7_4 _u /;10/ “an” 9_. 40. . ' - .27 _ ' Michele Ca‘sefl‘a. - 22* 57 Dec. 3,1946. M. CASE’RTA 2,411,851 APPARATUS FOR AND METHOD OF SMOOTHING PUMP 'BORES Fil'ed April 17, 1944 Y s Sheets-She‘et 2 - I Michele Caserl‘a Dec. 3, 1946. v _ M. CASERTA 2,411,851 APPARATUS FOR ‘AND METHOD OF SMOOTHING PUMP BORES v Filed‘ April 17, 1944 M \ _ 3 Sheets-Sheet 3 . wks I a Michele Caseria ' 2,411,851 Patented Dec. '3, i946 ' UNIT EDI.’ ‘ STATE s PATENT OFF-ICE‘ 2,411,851 ' APPARATUS FOR AND METHOD OF SMOOTHING PUDIP BORES Michele Caserta, Detroit, Mich., assignor to Thompson Products, Inc., a corporation of Ohio Application April 17, 1944, Serial No. 531,430 ' 14 Claims. (01. ‘51-34) 2 for forcing said blades radially outwardly and for operating said means to adjust the ‘position of said blades until they span a diametral length -This invention relates to an apparatus for and toa method of smoothing pump and other bores ‘without substantially altering the generated bore equal to the diameter of the ?nished bore. The ' ‘ ' In the construction of rotary vane pumps such Cl smoothing operation is ‘e?ected by rotating and reciprocating the-spindle carrying the blades rel as described and claimed in my co-pending appli ative to the pump liner. In a smoothing opera cation Serial No. 397,763, ?led June 12, 1941, tionas carried out by a, device of my invention, the pump bore is so contoured as to make the the radially extensible blades oscillate as a unit operation‘of thepump substantially non-pulsat ring.v This is accomplished by forming the bore 10 vin the diametral slot of the spindle end to follow the contour of the bore as initially formed in with a normal cross-sectional contour that com much ‘the same way as do the slidable vanes of prises a‘ pair. of opposite circle arcs having dif the rotor in the ?nished bore of a pump liner dur ferent radii but a common axis of generation, a ing the operation of ‘the pump. , Accordingly, it pairof opposite Archimedes spirals intermediate is possible by the use of my invention to smooth the circle arcs, and four parabolic spirals join a generated pump bore having a constant. di ing the ends of the circle arcs to the ends of ametral dimension through its axis of generation the Archimedes spirals, all of the curves having in a very simple and, ef?cient manner, while hold a common axis of generation and common tan ing the bore to very close tolerances. ~ gents at their points of juncture. A bore'of such It is therefore an important object of this in a contour is rather di?icult to form and to smooth 20 vention to provide an apparatus for smoothing properly, since the tolerances must, be held very bores of pumps, pump liners or the like where close indeed and owing to the non-cylindrical na such bores are of a generated contour having a turerof the bore, special tools andgrinding de constant diametral dimension through a com vices have to be employed. mon axis of generation. I > . : Iniaccordance with my present invention, the It is a further important object of this inven boreyof a pump, or Of-va pump liner, is formed in tion to provide a simple and rapid method of a series of operations... In the case of a pump smoothing the internal surfaces of pumps, or linen-a solid round billet is ?rst bored to form a pump liner bores, and the like where such sur cylindrical bore usingsubstantially the maximum lengthof radius that can be employed and yet 30 faces are formed from a plurality of curved sur faces having a common axis of generation and have the cylinder lie wholly within the ‘desired common tangents at their lines of juncture, but contour of the ?nished .bore. Ports are next are not cylindrical. cut in the sidewall of the liner and the proper Other and further important objects of this contour of vthe bore 'formedtherein by cam turn shape or contour. invention‘will be apparent from the disclosures ing or grinding, orby breaching. In this opera? tion, the bore is formed accurately to. the desired in-the speci?cation and the accompanying draw ingSi ; contour, but, to a thousandth of aninch or so . under the ?nal dimensions, just sufficient to per On the drawings: > Figure liis a side elevational view of an appa mit thedesired amount, of smoothing in the sub sequent honing operation. In the smoothing operation, to which the pres; ;»ent,_invention more particularly, relates,_ the ' - - 40 ratus embodying my invention; 'Figure 2 is a fragmentary, front elevational view to illustrate the operation of the clamping mechanism for holding said pump liner in posi smoothing is effected by a pair of abrasive sur tion'during the honing operation; ' faces, which are extensible outwardly along the diametral‘ plane in which they are mounted to 4 - Figure 3, is a fragmentary, top plan View of the pump liner clamping and holding means; bear against the internal bore surface of the Figure 41S a fragmentary, side elevational view pump liner with the desired amount of pressure. of the pump liner clamped in position; ' To accomplish this, a device is used that simu Figure 5 is an enlarged elevational View of a lates in some respects the rotor and vanes of a rotary vane pump, the abrasive surfaces, being 5 , provided by strips of honing stones or other abra sive material carried externally by a pair of radi ally extensible blades mounted in an adjustable assembly within a diametral slot in the end of \ l a, rotatable spindle. The assembly includes means 55 finished pump liner; Figure 6 is a diagrammatical cross-sectional ‘view of thepump liner'of Figure 5 indicating the ' axis of generation and the radii of the arcs and curves of which the pump bore is composed; ’ Figure 7 is a partly diagrammatic view of a 52,411,851 3 4 cylindrical billet being initially reamed to a cylin drical bore; Figure 8 is, a fragmentary, enlarged, sectional view taken substantially along the line VIII-VIII of Figure 10, with the honing device at the lowest ‘point of its reciprocating movement and with the honing strips radially retracted prior to the start of the smoothing operation, with parts‘ in ele holding mechanism is in its operative position, the pin 38 extends into the pin receiving socket 39 and the pump liner engaging portions 36 and 31 are clamped over the upper edge of a pump liner I4. In this position the lever 21 is sub stantially horizontal and the lever 29 lies forward of the'axis of the pivot pin‘132, which may be considered to bathe dead‘ center point of the mechanism. Accordingly, in its normal position, vation; Figure 9 is a view similar to Figure 8 but with 10 ‘the clamping mechanism can be thrown out of the honing device at the top of its strip and with the honing strips in operative position, with parts in elevation; Figure 10 is a top plan view of the honing de clamping engagement only by a manual pull upon the handle 28 to draw the lever arm 29 back and thus lift the arm 21. The clamping mechanism, ' in its inoperative position, is illustrated in dotted 15 lines in Figure 2. Figure 11 is a sectional view taken substantially There is also mounted for adjustment upon the along the line XI-XI of Figure 9; 1 post ll (Figure 1) a driving mechanism, indi Figure 12 is a sectional view taken substantially cated generally by the reference numeral 40, along the line XII—XII of Figure 8 with parts which comprises an arm 4| provided with a bore in elevation; and 20 42 through which said post I I extends. A thumb Figure 13 is a sectional view taken substantially screw 43 is provided for locking the arm 61 in vice; ~ ' along the line XIII-XIII_ of Figure 9. adjusted position upon said post. " A motor 44 is attached to said arm 4! at one side of the post H. Said motor has a vertical drive shaft 635 near the The reference numeral Ill (Figure 1) indicates generally a platform or base from which is mounted an upstanding post H for supporting the honing apparatus of my invention. Said ap~ paratus includes a work table I2 adjustably mounted upon said post i! and adapted to be held in adjusted‘position thereon by means of a lower end of which is mounted a pulley 46. Said pulley 46 is adapted to drive, by means of a belt 111, a secondpulleyJlB mounted upon the lower end ofya spindle 49 that extends through: a bore 50 in the free end of said arm 4|. A second pulley 5| is mounted upon the extreme lower end of said motor shaft 55 and is adapted to drive a disk 52 thumb screw 1%. The work table 12 is provided on its upper face with an annular, recessed holder 53 for receiving the lower end of a pump liner Ill. Said holder 13 may be integral with the work table [2 or mounted upon a pin 53 from the side of the motor housing. Since the pulley 5| and disk 52 are in planes at right, angles to each other, a pair of small pulleys 54 and-55 are used to guide the ‘?xedly attached thereto by- any suitable means. The holder i3 is provided with a cylindrical socket ‘I 5 for receiving the lower edgeof said pump liner driving, belt 55 that extends around said pulley 5i and disk 52. Said small pulleys 54 and 55 are supported from the motorv housing by means of a branched supporting bracket 51. The pulley 1B8 is mounted upon the lower end of the spindle 49 so that said spindle 49'm'ay be It with a snug ?t. Both the table 12 and'holder 13 are apertured, as indicated by the dotted line I6, to permit the honing device to project up wardly therethrough into the interior of the pump liner l4. rotatedby the motor 44 acting through the drive pulley 46 and the‘ drive belt 41. The hub 58 Also supported upon the table 12 is a clamping mechanism, indicated generally by the reference numeral 11. Said clamping mechanism I‘! (Fig __ure 2) comprises a pair of upstanding plates i8 of said pulley 43 is keyed on said spindle 49 by means of a spline 59 so as to permit reciprocal 4. movement of said spindle. 49 along its vertical axis, while the hub 58 is held against displace ment vertically between the horizontal arms of a U-shaped bracket 65 ?xedly secured to said secured to said work table '5 2 in any suitable man ner and having a spacer block 59 positioned therebetween. A rearwardly and upwardly in clined arm 26 is rigidly held at its lower end be tween said spaced plates H] by means of pins 2| and 22 extending therethrough. At the upper free end of said arm 28 there is pivotally mounted to said arm, by means of a pivot pin 23, a pair of lever arms 21 having bowed-apart end por-o tions 24 and 25. ‘A strip 28 extends between said end portions 25 and 25 inwardly of their extremi ties. A lever arm 29, having at its upper free end a handle 28, is pivotally mounted at its lower end, as by means of a pivot pin 3!, between said 60 upstanding plat-es i8. Said arm 29 is also piv otally connected near its free end, as at 33;, to a pair of short links 33.’ The other'ends of said links 30 are pivotally connected, as at 32 to the arms 21. The outer free ends 23 and‘ 25 of the lever arms 21 carry members 34 and 35, respec tively, that are provided with dependent clamp ing portions 35 and 31, respectively, adapted to arm Ill. The horizontal arms of the bracket Bil are apertured, as at 6|, to permit free passage of the spindle 49 therethrough. . A sleeve 62 is mounted upon said spindle 49 nea its upper end between'a pair of ?xed collars 63 and 64; Said sleeve 62 is loose upon the spindle vMi but because-"it'is held between the collars 63 and 64 is capable of‘ transmitting axial movement to said spindle t9. .Such axial movement is ac complished through a crank arm 65, one end 66 of which is adjustable in a slot>51 of said disk '52. The other end of said crank arm'65 is con nected by means of a pivot pin 68 to one end of a rod 55. The other end of said rod 69 is pro vided withv an eye 10 which engages’ a shaft 1| journaled in the spaced dependent sidewalls 12 of‘said table i2. A pinion 13 is ?xedly mounted upon said rotatable shaft 1|, so’ that as the disk 52 is revolved, the crank arm 65,-acting through overlie and engage the upper edge of a pump liner the rod 53, causes said pinion 13 to revolve ?rst l4. Said cross strip 26 is provided with a down- 70 in one and then in the other direction. Said wardly extending pin 38 for reception in a re pinion13 meshes with a rack 14 formed in the cess or socket 359. There is one such pin vreceiving recess or socket 39 in each end of a pump liner sleeve 62, whereby said sleeve 52, and consequent ly the spindle 49, is caused to reciprocate verti l4 (Figure 5). As shown in Figure 2, when the clamping and ‘ cally 'whenthe motor“ is running... i As best shown in Figures 8 to .13, inclusive, the meniber-M;v The degree of taper of the‘surfaces upper end“ of the spindle _49sis.provided~ with ‘a diametr'alIslotl5~whichextends clear to the end of said spindle and is partially .closed by anover 85 and 85d and of the surfaces :86 and 86a, is, of;' course,v.the 1 same so vthat the abrasive strips -8 I and182: are maintained exactly parallel to each lying'clisk .‘I6‘he1d‘ther‘eon by, means of screws 'I'Iu (Figure 10) . Within said slot ‘I5 is mounted " other, throughout their 'length while being moved the smoothing .or honing mechanism, .indicated generally by the reference numeral 11., Said mechanism 1'! comprises'a pa'ir'of members. "I8 and ‘I9, held against'axial displacement between radially outwardly during manual operation of within ‘said slot ‘I5.v Each of said members ‘I8 means of a;reamer IOI. the rod-93.5.-.’ ‘ :~ ' . -' . In v‘=‘1T)repa‘ring..:appump‘linerI4. for the honing operationabout to be described,v a solid cylindri the bottom 86 of said slot ‘I5 and the underside 10 cal billet»v may ?rst be provided with an eccentric but truly cylindrical bore. I60 (Figure 7) by of thecover disk ‘I6 but-bodily movable laterally Said bore I 00 is then re-formed to'the desired contour of the ?nished pump 'linergasior. instance to the contour indi abrasive strips 8| and ‘ 82; respectively. Said strips!“ and 82 may suitably comprise honing 15 catedby the dotted line I02. This may be accom plis'hed by broaching. Ports I03 and I04 are cut stones and are replaceable ‘when P'worntoo thin. into the: wall of the pump liner to the size and The members ‘I8 and 19 are provided'along their and '19 is longitudinallygrooved for receiving shape desired, either before‘or after the breaching operations The pump liner iI4 is also provided, bers wider areas of contact with the walls of‘the 20 priorrto the honing operation, with the pin re ceiving recesses 39 (Figure 5) extending inwardly slot ‘I5 and thus prevent said members from inner edges with opposed'tapered extensions 83 and 84 (Figure 11) that‘serv'e' to give said mem fromieachi of thesend faces on thethicker side wab-bling or becoming cocked in said slot. Each of said members ‘I8 and. ‘I9 is further provided at longitudinally > spaced points along their of- the 'pump liner. These recesses 39 also serve an'Palinement'i purpose in the assembly of the lengths ‘with inwardly directedv abutment por 25 pump-liner in a pump such as. shown in my 00-‘ pending application Serial No. 397,7 63, ?led June tions' 85. and 85a, and 86 and 86a for a purpose thatwill later appear‘; Said members ls‘an'd ‘I9 v:"The bo'rei I92 .at‘the start of the ‘honing opera are also provided with transverse slots 8'! and 81a tion‘lis‘ slightly .undersize' as'compared with the (Figures 8 and 9) for a purpose that willpresent ?nal dimensions of the bore IDZa (Figure 6)'in ly be described. > ' I ~ .12,1941_.=.;-' I v .> = - - ~ the ?nished pump liner. "Thecontourof theibore ‘~ Meansare provided for ‘forcing said members ‘I8 and'I9 laterally apart within the slot ‘I5. i" Such means include an integrally ,formed member 88 will, in accordance with knowniprinciples, have a common axis of generation, indicated bythe let' ter ‘1A1 v(Figure 6'): which will be concentric with (Figure 12) provided with‘a "slot l?9vexten‘ding laterally completely therethrough. "Said :mem 35 respect to the outer cylindrical surface I05 of said pump'liner. r-All' of the diameters of the pump ber 88 (Figure ‘8) is formed‘with' a wedge-shaped bore1'I82a passingvthrough said common axis of ‘generationfA will, of course, be of equal length. In accordancewith oneimethod of obtaining, a portion 89 at its upper end,lliiav'ingupwardly' con vergent outer ‘faces 96 and’90a, and- at its lower end with a‘wedge-shape'd' portion 9! havin'gialso upwardly convergent edges 92 and 92a.~'?A rod 40 93 is provided with a ‘lower threaded portion 94 that is adapted to ‘be engaged in a threaded'bore provided for‘that purpose in'the upper end of said z'rirembertlig-v Said rod 93 ‘carries ‘at itsrup per free end a'knur'led head795 to facilitate its tremities' of- said arcs I06--I 81' :and- I08-—I 09 are a3 pair of Archimedes: spirals Lille-III and H2 manual operation. » ‘At its- lower end thelrodi93 H3, which are joined to the extremities of- the is provided with a portion 96 of reduced vdiam: eter which is freely received in afsoclset ‘formed in'a ?oating bridge member. 9'I.'v Said bridge member 91 extends through the‘ slot'~I89 in said member 88‘ and theends of vsaid bridge'member extend freely» into the slots 91' and 81a in- said members wand-419.- ' ' _ a I ‘ -- - ' " circle arcs, by four, parabolic spirals, [OB-H2, IU‘I-IIO,il08-,-III, and_I09-—II3. All of these arcs and 'curveshave, a common axis of‘ genera tionsA, and they also ,‘have common tangents at ‘ their. points; of junction. All of the diameters passing'through said common axisiof generation 1 A, such asthe diameters I66-—.A—,-Iil8and I0fI-_— , ‘With the'honing ‘mechanism 11 in the posi tion shown in Figure 8,‘ that is with-the members ‘I8 and ‘I9’ in'their' inwardly" retracted state, a A.'—.‘LI09.fare of equal length. pump liner I4 can be slipped over theupper end ‘of said mechanism and clamped in‘ placelupon the work table I2. The threaded’ shaft 93 is then vmanually turned to move'the honing strip carry ing: members ‘I8 and ‘I9 outwardly into the posi tion‘ illustrated in ‘Figure 9. Upon threading said shaft 93'intothe r'nember_88, said member 88 is drawn upwardlyand the‘action of the 'ta pered surfaces 85 and 85:1,; and - 86 and 86a,v non-pulsating pump, the contour ofthe bore I 02a isformed by a pair of opposite circle arcspde?ned at'th’ei‘r extremitiesby thepoints -I 06 and H11, and bythepoints I88 and,,I09, formed with unequal radiiz-R and r,-respectiv_ely, Intermediate therex 60 I ' p , , . 1' -. ."It-lwill be .understood,vof~ course; that the par ticularlcon'tour 0f the bore‘iorms'no part'of the present invention‘, but isdescribed merely, for the purpose":of~illustration to show the type‘ of ‘work for-whichxmyi honing apparatus is particularly adapted- .IWhile capable of honing the surface of a’tr'uly' cylindrical .bore,-Jthe a'pparatushere de scribed 'is-im'ore “particularly designed for the hon ‘ingiiof'nonleylindrical‘ bores, which are neverthe lessv formed iwithia vcommon ‘axis of. generation vworking uponthe corresponding abutments 85 and'withfdiam‘eters of constant length. and 85a and 86 and 86a cause‘said'members ‘I8 and ‘I9 to be spread apart laterally until the be described: The operation‘not my honing‘ device will now I» ' ' A pump liner-‘I4 is inserted over the upper end surfaces of the honing ‘strips BI and 82 are in working engagement with? theinside surface of 70 of the spindle 49 carrying the honing device with the pump 'liner'rl?l The bridge 91, into which thellower, end ofthe shaft’ 93 extends, prevents longitudinal movement of said shaft 93 when ‘it “is being threaded 1 into for ‘out. of; the ‘member 88 and'thus causes relative 'a'xial‘movement of- the the‘honingistrips ‘8i and 82 in retracted position, as'illustrat'edin Figure-8; The pump liner I4 ?ts lsnugly‘in-to‘theirecess>I5 ofithe holder, I3; The - clamping-v J mechanism 1 I1 is :then moved into clamping-i position-,3’ as illustrated in full lines . in 2,411,851 7 8 Figure 2, the liner [4 having previously been ping the motor 44 by merely grasping the knurled‘ turned until the centering and aligning pin 38 end 95 and giving the rod 93 a twist. With a fair can be inserted into the socket or recess 39. The amount of experience, an operator can easily de lever 29 is then thrown over beyond the dead cen termine to what extent to adjust the diametral span of the abrasive strips 8| and 82, and adjust ter to clamp the pump liner l4 securely in the holder l3. ments are made whenever necessary during the operation of the device without interrupting ro ' Next, the rod 93 is manually turned to draw tation ofthe spindle. Ordinarily, the honing op upwardly the blade spreading mechanism 11 and eration requires avery brief period. thus force the honing strips 8| and‘82 outwardly The necessity for the smoothing operation into ?rm working engagement with the interior 10 surface of the bore |02a. ' arises from the fact that the bore cannot be per . fectly formed in the ?rst instance by broaching or the like. Also, there is usually some distortion due to the heat treatment step that follows The motor 44 is next started up to begin the honing operation. During the operation a cool ing ?uid, such as kerosene, may be run over the broaching. entire honing mechanism. The skirt |2| protects It is important to note that the method herein the driving mechanism from the kerosene. The length of the reciprocating stroke of the spindle described does not control the shape of the bore 49 should previously have been adjusted, by ad other than to insure constant diametral length, but is effectiveonly in giving to the bore a smooth justment of the eccentric pin 66 in the slot 61, so that at the extreme positions of the spindle in 20 ?nish without substantially altering the generated bore shape, and in making sure that all diameters its stroke, the honing strips 8| and 82 always through'the axis of generation A will have ex span the full length of the pump liner |4, that is, at the lowermost vposition of the spindle, the actly the same length. This insures vthat the upper ends of the honing strips 8| and 82 (Fig pump vanes will have exactly the same end clear ure 8) do not pass below the upper end of the 25 ance in all positions of the vanes within the bore. pump liner l4, while at the extreme uppermost If desired, the work table I2 can be swung very point of travel of the spindle 49, the lower ends slightly one way or the other to cause the abrasive of said honing strips 8| and 82 still lie below the strips 8| and 82 to bear more heavily when riding bottom edge of the pump liner M. This provision across the ports I03 and I04, thus giving more is importantif a straight Walled bore, rather than 30 clearance at those points and closer clearance in the pumping zones between ports, when the liner a bell mouth bore, is to be obtained. The amount of the reciprocation of the honing strips 8| and is assembled and the pump is in operation. 82 is preferably such as not to bring the ends of In order to permit the honing strips to be changed without taking the closure disc 16 off and said strips within the cut-out wall portions form ing the ports I03 and I04, since there would then lifting the mechanism 1'! out of the slot 15, the rim of the annular holder l3 (Figure 3) is cut be a tendency for the ends of the strips, if com away at opposite sides as at I20, to the lower edge ing within said cut-out portions, to catch on the. of the liner. The strips 8| and 82 can thus be edges of the port openings and eitherbe damaged removed laterally and changed with a minimum or wear away said edges unevenly, ' of effort. v In usual practice, the amount of abrasion of It will, of course, be understood that various the wall of said bore I02 effected by the'honing details of construction may be varied through a operation is of the order of 0.001 inch and is not wide range without departing from the principles intended to accomplish other than a, sufficient of this invention and it is, therefore, not the pur smoothing operation to make possible a smooth pose to limit the patent granted hereon otherwise sliding ?t between the bore and the vanes of the ‘ than necessitated by the scope of the appended rotor when the pump is assembled in an operat claims. ing condition. What I claim is: I As the spindle reciprocates, it is also rotated by 1. Apparatus for honing the internal surface of the drive including the pulleys 46 and 48 and the driving belt 41. The rate of rotation is suitably - a hollow article, the bore of which ‘has been formed with joined dissimilar surfaces of genera in the neighborhood of 400 R; P. M., but slower or faster rates of revolution can be employed de pending upon the type of work being done. As the spindle rotates, the entire blade carrying tion having a common axis of generation and diameters of constant length, said apparatus com ' prising a rotatable and reciprocable member hav such displacement along their diameters, the ing a diametrally extending slot, radially adjust able blades slidably positioned for movement in said slot and having strips of honing material projecting outwardly therefrom, means for ad justing said blades tobring said honing material into working contact with said internal surface and hold said blades after adjustment in rigidly members 18 and 79 slide Within the slot 15 with their upper edges confined by the closure J6. and with their lower edges resting against the lower .wall 80 of said slot 15. As previously explained, the extended contact surface areas provided by the extensions 83 and 84 between said members 18 and ?xed spaced relationship, and means for rotating and reciprocating ‘said member within said bore to effect the honing of said surface to smooth the same without materially altering the curvatures of said surfaces of generation, said blades being freely oscillatable in said slot during said honing ‘I9 and the lateral walls of said slot 15 Y tend to operation to permit said honing material to follow mechanism ‘H oscillates as a unitlaterally in a series of diametral planes, the honing strips 8| and 82 remaining in ?xed spaced relationship rel ative to each other. The movement of the as sembly is similar to that of .the vanes of a rotor in the operation of a vane type pump. . During 60 prevent wabbling or cocking of the members with the contour of said internal surface. 2. Apparatus for honing the internal surface of 70 in the slot. . . . > During the honing operation,‘ it maybe desir a hollow article, vthe bore of which has been formed with joined dissimilar surfaces of genera able to adjust the honing strips 8| and .82 out tion having a common axis of generation with all wardly into closer pressure relationship with the surface of the bore undergoing the smoothing op eration. ‘This can ‘be accomplished without stop is of the diameters of said bore, passing through said axis of constant length, said apparatuscom 52,411,851 ‘prising a‘rotatabl'e ‘and reciprocable member'hav ;ing a diametrally ‘extending slot, radially adjust able blades ‘slidably'positi‘oned. in said‘ slot_ and having strips of honing material projecting out wardly therefrom, means for adjusting said blades to bring said honing material into working-‘con ‘tactvwith said internal surface including means for holding said honing-material in adjusted ex tended'position'with the desired contact pressure againstlsaid surface‘, and means for ‘rotating and vreciprocating said member-‘within said bore to effect the honing of said surface to smooth the same, said'blades and blade adjusting and holding means being freely oscillatable in said slot to per mit said honing material to follow the contour of T10 cylindrical member‘ having" 'a' ‘slot extending diametrally therethrough,’a pair of radially. op posed blades mounted in said slot for movement therein along a diametral plane, honing strips carried by said bladesv and projecting outwardly therefrom, tapered elements for engaging inter nal faces of said blades, adjusting meansasso ciated with said tapered'elements for moving said blades radially outwardly uniformly of their lengths,>said-adjusting means including an'ex .tension' projecting beyond an end of said cylin drical' member and manually operable during rotation of said’ cylindrical member, said honing ' strips, tapered'elements and adjusting means constituting a unit of rigidly ?xed diametral ‘length for any given adjustment and said~unit ‘being movable in said slot, and means forrota't the curvatures of said surfaces of generation; ing said cylindrical member to cause said honing 3. Apparatus for honing‘ the internal surface strips to smooth an internal bore with which said of a ‘hollow article, the bore of which has been formed with joined dissimilar surfaces of genera 20 strips may be adjusted into contact. said internalsurface withoutmaterially altering tion having a common axis of generation and constant diametral dimensions, said apparatus comprising an adjustable supporting ?xture for holding said article with the bore thereof unob structed, a- rotatable and reciprocable member - having a diametrally extending slot, an assembly slidably positioned in said slot and having strips of honing material projecting outwardly there ’ from, means associated with said assembly for extending said blades to bring said honing mate rial into working contact with said internal sur face, and means for rotating and reciprocating said member within said bore to effect the honing of said surface to smooth the same, said assembly being freely oscillatable in said slot to permit said ' honing material to follow the contour of said internal surface without materially altering the curvatures of said surfaces of generation. 8. In an apparatus of the class described, a rotatable and reciprocable shaft having an open ended slot extending through the axis thereof, a closure member for the end of said slot and an assembly retained by said closure member and freely oscillatable in said slot as a unit of ?xed diametral length during operation of said shaft including outwardly projecting parallel strips of abrasive material for the smoothing of internal surfaces. 9. In an apparatus of the class described, a rotatable and reciprocable member having a slot extending through the axis thereof and an as sembly freely oscillatable in said slot during oper ation of said member including outwardly pro jecting strips of abrasive material for the smooth-7 ing of internal surfaces, said assembly also in cluding tapered elements associated with said strips for moving the same into outwardly pro jecting position and means for actuating said ta 40 member having a diametral sl'ot, radially opposed 4. In an apparatus of the class described, a blades insaidslot carrying outwardly projecting honing surfaces, tapered rigid elements between ' said blades and in contact therewith for moving said blades into radially extended positions, and an adjusting member cooperating with said ta pered elements to effect such radial extension of said blades and said tapered elements, said blades pered elements during operation of said member. 10. In an apparatus of ‘the class described, a rotatable and reciprocable member having a slot , extending through the axis thereof and an as sembly freely oscillatable in said slot during op - eration of said member including outwardly pro jecting strips of abrasive material for the smooth ing of internal surfaces, said assembly also in cluding tapered elements associated with said diametral plane without change in diametral strips for moving the same into outwardly pro 50 length. jecting position and means for actuating said ta-’ 5. In an apparatus of the class described, a pered elements during operation of said member, member having a diametral slot, radially opposed said means including a ?oating bridge and a blades in said slot carrying outwardly projecting manually operable member coacting therewith to honing surfaces, means associated with said blades cause said tapered elements to force said strips for moving said blades into radially extended outwardly. positions and providing a rigid backing for said 11. The method of smoothing an internal non blades, and an adjusting member cooperating .cylindrical surface composed of a plurality of dis with said means to effect such radial extension similar surfaces‘ of generation having a constant of said blades, said blades and said rigid backing diametral length through the common ‘axis of means being oscillatable in said slot along a generation of said surfaces, said method compris diametral plane‘ without change in diametral being oscillatable as a ‘unit in said slot along a ing adjusting a pair only of honing surfaces ; length. ' ' 6. In an apparatus of the classdescribed, a radially outwardly into working contact with said internal surface, said honing surfaces being member having a diametral slot, radially opposed blades in said slot carrying outwardly projecting 65 maintained in parallelism in all positions to the common axis of generation and being oscillated -without relative movement therebetween in blades for moving said blades into radially ex qplanes passing through said common'axis of gen tended positions and providing a rigid backing eration and rotating and reciprocating said hon for said blades, and a manually operable threaded ing surfaces relative to said internal bore surface. adjusting member cooperating with said tapered " 12. The method of smoothing an internal sur elements to effect such radial extension of said face the contour of which is composed of a plu blades, said blades and tapered elements being rality of dissimilar surfaces all having a common oscillatable as a unit in said slot along a diam axis of generation and the diameters of which etral plane without change in diametral length. passing through said common axis are all of con '7. In an apparatus of the class described, a. honing surfaces, tapered elements between said 11 2,411,851 'stan-t length, said method comprising adjusting a pair only of honing surfaces radially outwardly into pressure relationship with said internal sur face throughout the length thereof, holding said honing surfaces in relatively ?xed spaced parallel relationship to the common axis of generation but freely oscillatable in all diametral planes .pass ing through said common axis of generation and rotating and reciprocating said honing surfaces ‘relative to said internal surface While maintain ing said honing surfaces at all times parallel to each other and in abrading relationship to said internal surface to smooth the same. 13. In an apparatus of the class described, a rotatable and reciprocable shaft having an axially elongated slot extending transversely there through, and an assembly con?ned within the axial length of said slot but freely oscillatable as a unit of ?xed diametral length in said slot trans 12 .versely of said shaftduring operation thereof, said assembly including a pair of diametrally op .posed, outwardly projecting, narrow strips of abrasive material for the smoothing of internal surfaces. 14. In an apparatus for ?nishing a generated bore the cross section of which is characterized by the diameters through its center of generation being all of the same length, a member rotatable 10 about the axis of generation of said bore and axially reciprocal along said axis, said member being provided with a slot in a plane passing through said axis, and an assembly in said slot oscillatable therein as a'unit, said assembly in cluding a pair of opposed parallel abrasive strips to contact the wall of said bore and including means to positively spread said abrasive. strips While keeping the same parallel to said axis. MICHELE CASERTA.